{"id": "1728574", "revid": "196446", "url": "https://en.wikipedia.org/wiki?curid=1728574", "title": "Flavor scalping", "text": "Flavor scalping is a term used in the packaging industry to describe the loss of quality of a packaged item due to either its volatile flavors being absorbed by the packaging or the item absorbing undesirable flavors from its packaging. A classic example is the absorption of various plastic flavors when soft drinks are stored in plastic bottles for an extended period.", "Engineering,_Manufacturing": 1.0000032187, "qwen": "Yes"}
{"id": "893562", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=893562", "title": "Magma (company)", "text": "MAGMA Gießereitechnologie GmbH is a developer and supplier of software for casting process simulation. \nIntroduction.\nThe company was founded in 1988 and has its headquarters in Aachen, Germany. MAGMA's product and service portfolio includes simulation software MAGMASOFT, with the newest release MAGMA5, as well as engineering services for casting design and optimization. The software is used world-wide by foundries, casting buyers and designers, especially for the optimization of cast components in automotive and heavy industry applications. German newspaper Süddeutsche Zeitung cites MAGMA amongst the global market leaders for simulation software for casting processes.\nWorldwide, MAGMA employs more than 200 people in software development, support, marketing, and administration, of which 90 are in Aachen. The company also has offices and subsidiaries in the United States, Singapore, Brazil, Korea, Turkey, India, China, and the Czech Republic.\nMAGMA5.\nMAGMA5 is used for the simulation of casting processes. The software stands for the prediction of the entire casting component quality and process chain by providing a better understanding of mold filling, solidification and cooling and allows the quantitative prediction of mechanical properties, thermal stresses and distortions of the resulting castings. The simulation describes a cast component's quality up-front before production starts and the casting method can be designed with respect to the required component properties. This results in a reduction in pre-production sampling as the precise layout of the complete casting system leads to energy, material, and tooling savings.\nMAGMA5 consists of a base module and a set of additional modules that cover all steps of the casting production. The range of application of MAGMA solutions comprises all cast alloys, from cast iron to aluminum sand casting, permanent mold and die casting up to large steel castings. The software supports the user in the modeling of the component, the determination of melting practice and casting methoding through to model and mold making, heat treatment, and finishing. ", "Engineering,_Manufacturing": 1.0000054836, "qwen": "Yes"}
{"id": "36883359", "revid": "39544904", "url": "https://en.wikipedia.org/wiki?curid=36883359", "title": "Dynamic manufacturing network", "text": "Definition.\nA dynamic manufacturing network (DMN) is a coalition, either permanent or temporal, comprising production systems of geographically dispersed small and medium enterprises and/or original equipment manufacturers that collaborate in a shared value-chain to conduct joint manufacturing.\nThe dynamic manufacturing networks are an approach that helps to manage risks and increase benefits in the manufacturing sector. The DMNs are a proposed solution to increase the efficiency and reduce the time needed to design and operate a new manufacturing network, or to reconfigure an existing one.\nApplications.\nManufacturing networks have become increasingly common in applied research on manufacturing, since several manufacturing enterprises have shown interest for creating such networks and take advantage of them both for collaborative product development and for supply chain optimization.\nDuring the last decade the effort is mainly focused on the dynamic management of the manufacturing networks, as proven by several studies published by Accenture, MIT\n and University of St. Gallen ", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "12155118", "revid": "7304862", "url": "https://en.wikipedia.org/wiki?curid=12155118", "title": "Johnson's rule", "text": "In operations research, Johnson's rule is a method of scheduling jobs in two work centers. Its primary objective is to find an optimal sequence of jobs to reduce makespan (the total amount of time it takes to complete all jobs). It also reduces the amount of idle time between the two work centers.\nThe method minimizes the makespan in the case of two work centers. Furthermore, the method finds the shortest makespan in the case of three work centers if additional constraints are met.\nAlgorithm.\nThe technique requires several preconditions:\nJohnson's rule is as follows: \nGiven significant idle time at the second work center (from waiting for the job to be finished at the first work center), job splitting may be used.\nExample.\nEach of five jobs needs to go through work center A and B. Find the optimum sequence of jobs using Johnson's rule.\nSo, the jobs must be processed in the order C → A → D → E → B, and must be processed in the same order on both work centers.", "Engineering,_Manufacturing": 1.0000071526, "qwen": "Yes"}
{"id": "10557873", "revid": "32990417", "url": "https://en.wikipedia.org/wiki?curid=10557873", "title": "Dieline", "text": "A dieline is used in graphic design as a placeholder for assisting in the proper layout of a document that will be diecut as part of the finishing process. Dielines can also indicate perforation, cutting, and folding marks for flat packaging. It is usually placed into the graphic's computer file as a separate layer for sizing and orientation purposes. A dieline is usually not printed on the final piece but is used to determine correct layout. They are useful both for aesthetic purposes and to avoid manufacturing errors by acting as a blueprint. A Dieline can be created using graphic design software like Adobe Illustrator.\nDielines are traditionally used when designing:", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "31205078", "revid": "27976443", "url": "https://en.wikipedia.org/wiki?curid=31205078", "title": "Liquid Impact Forming", "text": "Liquid Impact Forming is a metalworking process in which the combined use of a stamping press and a liquid medium forms the desired shape on the workpiece. This technique is a synthesis of two metalworking processes; stamping (metalworking) and hydroforming. It is especially suited for the cold forming of tubular structural parts in automotive, railroad and aerospace industries.\nThe process is based on a patent by Stanley Ash from the Greenville Tool & Die Company in Greenville, Michigan.\nProcess.\nLiquid impact forming uses the principles of hydroforming process with conventional stamping equipment. Even though hydroforming offers great advantages over conventional tube stamping through the reduction of manufacturing steps and the reduction of variation in workpieces, it still requires expensive mechanical equipment such as dies to withstand extreme pressures and pressurizing equipment such as pumps and intensifiers. As an alternative to this, the liquid impact forming utilizes the increase in the internal pressure of the liquid inside of a tube during the stamping process, eliminating the need for the use of above mentioned equipment.\nThe process includes the following stages:\n1. A metal tube is filled with a liquid, preferably water and placed between lower and upper die sections of stamping dies.\n2. The ends of the liquid-filled tube are sealed to confine the liquid within the tube at approximately atmospheric pressure.\n3. The liquid-filled sealed tube is stamped in a conventional die to form the tube into a desired configuration, such as a box-shaped structural member. The compressive forces produced as the die closes to form stamped tube also compress the liquid within the interior of the sealed tube as it changes shape. Thus, the pressure of the liquid increases as the die closes. As the liquid resists compression, it forces the tube walls outwardly toward the interior surface of the die cavity. Once die sections are fully closed around the sealed tube, the tube walls take the shape of the die cavity.\n4. The remaining liquid is drained from the formed tube.\nApplications and Variations.\nThe liquid impact forming process is especially advantageous for the cold forming of tubular structural parts in automotive, railroad and aerospace industries. It may be used in the cold forming of cylindrical or non-cylindrical parts. It is limited for the applications requiring extensive metal flow or bulging because of the absence of external pressure utilization as in hydroforming.\nOne further variation of the liquid impact forming comprises the use of a change-of-state material in liquid state in order to prevent the tube wall from buckling or wrinkling during piercing. The change-of-state material can be water or a metallic lead-bismuth alloy. The liquid can be frozen before the stamping phase. After stamping, the liquid can be melted and drained from the shaped tube. Other applications of the process would be the piercing or bulging of tubes, which could also include the use of the change-of-state material.", "Engineering,_Manufacturing": 1.0000004768, "qwen": "Yes"}
{"id": "52160450", "revid": "43558034", "url": "https://en.wikipedia.org/wiki?curid=52160450", "title": "Supply chain collaboration", "text": "In supply chain management, supply chain collaboration is defined as two or more autonomous firms working jointly to plan and execute supply chain operations. It can deliver substantial benefits and advantages to collaborators. It is known as a cooperative strategy when one or more companies or business units work together to create mutual benefits. There are two main types of supply chain collaboration: vertical collaboration and horizontal collaboration. Vertical collaboration is the collaboration when two or more organizations from different levels or stages in supply chain share their responsibilities, resources, and performance information to serve relatively similar end customers; while horizontal collaboration is an inter-organizational systemrelationship between two or more companies at the same level or stage in the supply chain in order to allow greater ease of work and cooperation towards achieving a common objective.\nSupply chain collaboration should not be confused with 'Operational Collaboration'. Operational Collaboration is when a supplier checks in with a buying organization for example. Supplier Collaboration focuses on collaborative goals that deliver value to both the buying and selling organization.\nDifferent forms and approaches of supply chain collaboration.\nCollaborative communication.\nCollaborative communication is the contact and message transmission process among supply chain partners in terms of frequency, direction, mode, and influence strategy. Open, frequent, balanced, two-way, multilevel communications indicate close inter-firm relationships.\nCollaborative Execution.\nCollaborative execution is the process of executing supply chain transactions in a collaborative manner. Suppliers will work with buyers to ensure the right quantity of materials is delivered in the right time as per the contract. As the purchase order goes through its life cycle of order to delivery, at each stage there needs to be a tight collaboration between the trading partners for correct and efficient execution.\nOpen Supply Chain Innovation.\nInspired by the Open Innovation approach, supply chain networks can facilitate innovation platforms where n-tier supplier chain actors and partners beyond the supply chain network can collaborate, co-create, and co-innovate. The open supply chain collaboration builds upon three ambidextrous capabilities: knowledge exploration and exploitation, horizontal and vertical collaboration, incremental and radical innovation.\nCoordinating contract.\nCoordinating contract is defined as a coordination mechanism that provides incentives to all of its members so that the decentralized supply chain behaves nearly or exactly the same as the integrated one, by specifying contract parameters such as quantity, price, quality and deadlines, contracts are designed to improve supplier-buyer relationship.\nInformation sharing.\nInformation sharing is the extent to which a firm shares a variety of relevant, accurate, complete, and confidential ideas, plans, and procedures with its supply chain partners in a timely manner.\nJoint decision making.\nJoint decision making refers to the process where supply chain partners orchestrate decisions in supply chain planning and operations that optimize supply chain benefits.\nJoint knowledge creation.\nJoint knowledge creation is the extent to which supply chain partners develop a better understanding of and response to the market and competitive environment by working together.\nResource sharing.\nResource sharing is the process of leveraging capabilities and assets and investing in capabilities and assets with supply chain partners.", "Engineering,_Manufacturing": 0.9890819788, "qwen": "Yes"}
{"id": "1643482", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1643482", "title": "Tool bit", "text": "In machining, a tool bit is a non-rotary cutting tool used in metal lathes, shapers, and planers. Such cutters are also often referred to by the set-phrase name of single-point cutting tool, as distinguished from other cutting tools such as a saw or water jet cutter. The cutting edge is ground to suit a particular machining operation and may be resharpened or reshaped as needed. The ground tool bit is held rigidly by a tool holder while it is cutting.\nGeometry.\nBack rake is to help control the direction of the chip, which naturally curves into the work due to the difference in length from the outer and inner parts of the cut. It also helps counteract the pressure against the tool from the work by pulling the tool into the work.\nSide rake along with back rake controls the chip flow and partly counteracts the resistance of the work to the movement of the cutter and can be optimized to suit the particular material being cut. Brass for example requires a back and side rake of 0 degrees while aluminum uses a back rake of 35 degrees and a side rake of 15 degrees.\nNose radius makes the finish of the cut smoother as it can overlap the previous cut and eliminate the peaks and valleys that a pointed tool produces. Having a radius also strengthens the tip, a sharp point being quite fragile. Nose radius varies depending on the machining operations like roughing, semi-finishing or finishing and also on the component material being cut: steel, cast iron, aluminium and others.\nAll the other angles are for clearance in order that no part of the tool besides the actual cutting edge can touch the work. The front clearance angle is usually 8 degrees while the side clearance angle is 10-15 degrees and partly depends on the rate of feed expected.\nMinimum angles which do the job required are advisable because the tool gets weaker as the edge gets keener due to the lessening support behind the edge and the reduced ability to absorb heat generated by cutting.\nThe rake angles on the top of the tool need not be precise in order to cut but to cut efficiently there will be an optimum angle for back and side rake.\nMaterials.\nSteels.\nOriginally, all tool bits were made of high carbon tool steels with the appropriate hardening and tempering. Since the introductions of high-speed steel (HSS) (early years of the 20th century), sintered carbide (1930s), ceramic and diamond cutters, those materials have gradually replaced the earlier kinds of tool steel in almost all cutting applications. Most tool bits today are made of HSS, cobalt steel, or carbide.\nCarbides and ceramics.\nCarbide, ceramics (such as cubic boron nitride) and diamond, having higher hardness than HSS, all allow faster material removal than HSS in most cases. Because these materials are more expensive and brittler than steel, typically the body of the cutting tool is made of steel, and a small cutting edge made of the harder material is attached. The cutting edge is usually either screwed or clamped on (in this case it is called an insert), or brazed on to a steel shank (this is usually only done for carbide).\nInserts.\nAlmost all high-performance cutting tools use indexable inserts. There are several reasons for this. First of all, at the very high cutting speeds and feeds supported by these materials, the cutting tip can reach temperatures high enough to melt the brazing material holding it to the shank. Economics are also important; inserts are made symmetrically so that when the first cutting edge is dull they can be rotated, presenting a fresh cutting edge. Some inserts are even made so that they can be flipped over, giving as many as 16 cutting edges per insert. There are many types of inserts: some for roughing, some for finishing. Others are made for specialized jobs like cutting threads or grooves. The industry employs standardized nomenclature to describe inserts by shape, material, coating material, and size.\nForm tools.\nA form tool is precision-ground into a pattern that resembles the part to be formed. The form tool can be used as a single operation and therefore eliminate many other operations from the slides (front, rear and/or vertical) and the turret, such as box tools. A form tool turns one or more diameters while feeding into the work. Before the use of form tools, diameters were turned by multiple slide and turret operations, and thus took more work to make the part. For example, a form tool can turn many diameters and in addition can also cut off the part in a single operation and eliminate the need to index the turret. For single-spindle machines, bypassing the need to index the turret can dramatically increase hourly part production rates.\nOn long-running jobs it is common to use a \"roughing tool\" on a different slide or turret station to remove the bulk of the material to reduce wear on the form tool.\nThere are different types of form tools. Insert form tools are the most common for short- to medium-range jobs (50 to 20,000 pcs). Circular form tools are usually for longer jobs, since the tool wear can be ground off the tool tip many times as the tool is rotated in its holder. There is also a skiving tool that can be used for light finishing cuts. Form tools can be made of cobalt steel, carbide, or high-speed steel. Carbide requires additional care because it is very brittle and will chip if chatter occurs.\nA drawback when using form tools is that the feed into the work is usually slow, 0.0005\" to 0.0012\" per revolution depending on the width of the tool. Wide form tools create more heat and usually are problematic for chatter. Heat and chatter reduces tool life. Also, form tools wider than 2.5 times the smaller diameter of the part being turned have a greater risk of the part breaking off. When turning longer lengths, a support from the turret can be used to increase turning length from 2.5 times to 5 times the smallest diameter of the part being turned, and this also can help reduce chatter. Despite the drawbacks, the elimination of extra operations often makes using form tools the most efficient option.\nToolholders.\nBy confining the expensive hard cutting tip to the part doing the actual cutting, the cost of tooling is reduced. The supporting tool holder can then be made from a tougher steel, which besides being cheaper is also usually better suited to the task, being less brittle than the cutting-edge materials.\nThe tool holders may also be designed to introduce additional properties to the cutting action, such as:\nNote that since stiffness (rather than strength) is usually the design driver of a tool holder, the steel used doesn't need to be particularly hard or strong as there is relatively little difference between the stiffnesses of most steel alloys.\nHolders used on lathes.\nBit holder and toolpost.\nThe \"toolpost\" is the part of a metalworking lathe which either holds the tool bit directly or holds a toolholder which contains the tool bit. There are a great variety of designs for toolposts (including basic toolposts, rocker toolposts, quick-change toolposts, and toolpost turrets) and toolholders (with varying geometry and features).\nBox tool.\nA box tool is mounted on the turret of a turret lathe or screw machine. It is essentially a toolpost that brings its follower rest along with it. A tool bit (or several tool bits) and a compact follower rest (usually V-shaped or with two rollers) are mounted opposite each other in a body which surrounds the workpiece (forms a \"box\" around it). As the tool bit puts a lateral deflecting force on the workpiece, the follower rest opposes it, providing rigidity. A different and popular type of box tool uses two rollers rather than a follower rest. One roller is called a \"sizing roller\" and the other roller is called a \"burnishing roller\". The rollers turn with the stock to reduce scarring on the finished turn. Opposing tool bits may be used (instead of a rest) to cancel each other's deflecting forces (called a \"balanced turning tool\"), in which case the box tool begins to overlap in form, function, and identity with a hollow mill.\nHolders used on shapers, slotters, and planers.\nClapper box.\nShapers, slotters, and planers often employ a kind of toolholder called a \"clapper box\" that swings freely on the return stroke of the ram or bed. On the next cutting stroke, it \"claps\" back into cutting position. Its movement is analogous to that of a butterfly-style check valve.\nHolders used on milling machines.\nFly cutters.\nFly cutters are a type of milling cutter in which one or two tool bits are mounted. The bits spin around with the rotation of the spindle, taking facing cuts. Fly cutters are an application of tool bits where the bits are part of a rotary unit (whereas most other tool bit use is linear).\nHistory.\nTool bits have been used for centuries, yet their further technological development continues even today. Before about 1900, almost all tool bits were made by their users, and many machine shops had forges. In fact, good machinists were expected to have blacksmithing knowledge, and although the chemistry and physics of the heat treatment of steel were not well understood (as compared with today's sciences), the practical \"art\" of heat treatment was quite advanced, and something that most skilled metalworkers were comfortably acquainted with. Tool bits were made of carbon tool steels, which have high enough carbon content to take hardening well. Each bit was forged with a hammer, quenched, and then ground with a grindstone. The exact details of the heat treatment and tip geometry were a matter of individual experience and preference.\nA substantial technological advance occurred in the 1890–1910 period, when Frederick Winslow Taylor applied scientific methods to the study of tool bits and their cutting performance (including their geometry, metallurgy, and heat treatment, and the resulting speeds and feeds, depths of cut, metal-removal rates, and tool life). Along with Maunsel White and various assistants, he developed high-speed steels (whose properties come from both their alloying element mixtures and their heat treatment methods). His cutting experiments chewed through tons of workpiece material, consumed thousands of tool bits, and generated mountains of chips. They were sponsored in large part by William Sellers (a principal of Midvale Steel and Cramp's shipyard) and later by Bethlehem Steel. Not only did Taylor develop new materials to make single-point cutters from, but he also determined optimum geometry (rake angles, clearance angles, nose radiuses, etc.). He developed Taylor's Equation for Tool Life Expectancy. After Taylor, it was no longer taken for granted that the black art of individual craftsmen represented the highest level of metalworking technology. This was part of a larger trend during the 19th and 20th centuries by which science was mixed with art in the material culture of everyday life (applied science).\nStellite soon joined high-speed steels as a material for single-point cutters. Although diamond turning had been around for a long time, it was not until these new, expensive metals came about that the idea of cutting inserts became commonly applied in machining. Before this, most single-point cutters were forged entirely of tool steel (then ground at the tip). Now it became more common to attach a separate tip (of one material) to a holder (of another). With the development of commercially available cemented carbide (1920s) and ceramic inserts (post-WWII), this trend accelerated, because carbide and ceramic are even more expensive and even less suited to serving as a shank. The technological development, however, did not immediately displace the older ways. Between 1900 and 1950, it was still not uncommon for a machinist to forge a tool from carbon tool steel.\nToday, among the single-point cutters used in mass production (such as of automotive parts), insert tools using carbide and ceramic far outnumber HSS or cobalt steel tools. In other machining contexts (e.g., job shops, toolrooms, and hobbyist practice), the latter are still well represented. An entire system of industry-standard notation has been developed to name each insert geometry type. The number of carbide and ceramic formulations continues to expand, and diamond is used more than ever before. Speeds, feeds, depths of cut, and temperatures at the cutting interface continue to rise (the latter counterbalanced by copious cooling via liquid, air, or aerosols), and cycle times continue to shrink. Competition among product manufacturers to lower the unit costs of production continually drives technological development by the tool manufacturers, as long as the costs of R&D and tooling purchase amortization are lower than the amount of money saved by productivity increases (e.g., wage expense reduction).", "Engineering,_Manufacturing": 0.9999673367, "qwen": "Yes"}
{"id": "1646504", "revid": "13286072", "url": "https://en.wikipedia.org/wiki?curid=1646504", "title": "Countersink", "text": "A countersink (symbol: ⌵) is a conical hole cut into a manufactured object, or the cutter used to cut such a hole. A common use is to allow the head of a countersunk bolt, screw or rivet, when placed in the hole, to sit flush with or below the surface of the surrounding material (by comparison, a counterbore makes a flat-bottomed hole that might be used with a socket-head capscrew). A countersink may also be used to remove the burr left from a drilling or tapping operation thereby improving the finish of the product and removing any hazardous sharp edges.\nThe basic geometry of a countersink (cutter) inherently can be applied to the plunging applications described above (axial feed only) and also to other milling applications (sideways traversal). Therefore, countersinks overlap in form, function, and sometimes name with chamfering endmills (endmills with angled tips). Regardless of the name given to the cutter, the surface being generated may be a conical chamfer (plunging applications) or a beveled corner for the intersection of two planes (traversing applications).\nTypes.\nMachining.\nA countersink may be used in many tools, such as drills, drill presses, milling machines, and lathes.\nCross-hole countersink cutter.\nA cross-hole, \"Weldon style\" or \"zero flute\" countersink is a cone-shaped tool with a cutting edge provided by a hole that goes through the side of the cone. The intersection of the hole and cone form the cutting edge on the tool. The cone is not truly symmetrical as it is essential that the cone retreats away from the cutting edge as the tool rotates providing clearance. If this does not occur the cutting edge will lack clearance and rub rather than \"bite\" into the material. This clearance is referred to as cutting relief.\nThese tools are best used as deburring tools, where the burr from a previous machining operation needs to be removed for cosmetic and safety reasons, however they may be used in softer materials (such as wood or plastic) to create a countersunk hole for a screw.\nFluted countersink cutter.\nThe fluted countersink cutter is used to provide a heavy chamfer in the entrance to a drilled hole. This may be required to allow the correct seating for a countersunk-head screw or to provide the lead in for a second machining operation such as tapping. Countersink cutters are manufactured with six common angles, which are 60°, 82°, 90°, 100°, 110°, or 120°, with the two most common of those being 82° and 90°. Countersunk-head screws that follow the Unified Thread Standard very often have an 82° angle, and screws that follow the ISO standard very often have a 90° angle. Throughout the aerospace industry, countersunk fasteners typically have an angle of 100°.\nBack countersink.\nA \"back countersink\", also known as an \"inserted countersink\", is a two piece countersink used on tough to reach areas. One component is a rod that is inserted into the existing hole in the workpieces; the other component is the cutter, which is attached to the rod, or extends out of it, after it is in position. This is comparable to other types of \"back-\" machining, such as back-spotfacing, back-boring, back-counterboring, back-milling, and back-deburring. The common theme is accomplishing machining operations on the far side of the workpiece from the spindle face, which obviates a \"second operation\" setup. This reduces setup time and frustration in several ways. Not only does it obviate the flipping over, cleaning, reclamping, etc., but it also can allow effortless high concentricity, parallelism, and squareness with the first setup's datum without the hassle of reestablishing it on another setup (via painstaking indicating).\nSpeeds, feeds, and avoiding chatter.\nIt can often be difficult to avoid chatter when cutting with countersink cutters. As usual in machining, the shorter and more rigid the setup, the better. Better-quality fluted countersink cutters sometimes have the flutes (or at least one flute) at an irregular pitching. This variation in pitching reduces the chance of the cutting edges setting up a harmonic action and leaving an undulated surface. This surface ripple is also dependent on the surface speed of the cutting edges, material type, and applied pressure (or feed rate); once started it is hard to remove. Too light a feed tends to increase chatter risk. As in many other machining operations, an appropriate response to the chatter may be to decrease speed and increase feed. On a drill press, the slowest available spindle speed is usually best. With a variable-speed handheld power drill, the trigger is best squeezed lightly to yield a low spindle speed.\nGood chatter-free results can usually be had by countersinking by hand (as opposed to running the tool in a powered spindle). The slow speed and sensitive feed tend to prevent chatter. With a quarter-inch-hex shank, the countersink cutter can be held with a screwdriver handle of the indexable-bit type.\nForm countersinking.\nForm countersinking, also known as \"dimpling\", is a countersink that is formed into sheet metal to increase the strength of a structure as the countersinks of multiple pieces nest together. There are two processes for producing formed countersinks: \"coin dimpling\" and \"modified radius dimpling\". Such dimples in fairly thick sheet can even be tapped to yield a threaded hardpoint on the sheet without the bother and expense of welding a nut to the sheet. This style of construction is often seen in modern household appliance design, because it allows the product to be lower-priced, and the quality can still be good as long as the sheet is thick enough.", "Engineering,_Manufacturing": 0.9999908209, "qwen": "Yes"}
{"id": "1647023", "revid": "14013403", "url": "https://en.wikipedia.org/wiki?curid=1647023", "title": "Hand scraper", "text": "A hand scraper is a single-edged tool used to scrape metal or other materials from a surface. This may be required where a surface needs to be trued, corrected for fit to a mating part, needs to retain oil (usually on a freshly ground surface), or to give a decorative finish.\nSurface plates were traditionally made by scraping. Three raw (plates that have been `seasoned` or residual stress relieved and received suitable surface treatments, but unfinished) cast surface plates, a flat scraper (as pictured at the top of the image) and a quantity of bearing blue (or red lead) were all that was required in the way of tools.\nThe scraper in the center of the image is a three corner scraper and is typically used to deburr holes or the internal surface of bush type bearings. Bushes are typically made from bronze or a white metal.\nThe scraper pictured at the bottom is a curved scraper. It has a slight curve in its profile and is also suitable for bush bearings, typically the longer ones.\nOne advantage of scraping is the ability to take the tool to the workpiece, this can be useful when the workpiece weighs several tons and is difficult to move.\nIt is done by using a precision surface such as a surface plate or a straight edge as a standard (a straight edge in this context is not a ruler; it is a miniature surface plate of extreme accuracy). The standard is coated with a very thin coating of a material such as Prussian blue. The work piece and standard are touched together by gravity alone and the high spots on the work piece will be colored by the dye on the standard. These high spots are scraped off and the process repeated until there is an even spread of high spots which total about 60% or more of the surface area. Coarse scraping gives a resulting surface with 5-10 points per square inch while fine scraping yields 24-36 points per square inch. If desired the surface can then be “Frosted”. A surface prepared in this way is superior in overall accuracy to any prepared by machining or grinding operations, although lapping can equal or exceed it over small distances. Grinding and machining stresses the metal thermally and mechanically, scraping and lapping do not. \nScraping is the only method for producing an original set of flat surfaces from which one can transfer that accuracy through to other surfaces by means of grinding. Lapping and grinding do not achieve the long distance flatness scraping can, as they act on the entire surface rather than local high or low spots. \nWith precision ground surfaces, any oil film applied to the surface will lack the means to adhere to the surface, especially between two mating parts of exceptional finish. The oil film will be swept away leaving nothing but bare metal and the risk of seizure. Carefully scraping the surface will leave the original high quality surface intact, but provide many shallow depressions where the oil film can maintain its depth and surface tension. When scraping is used for this purpose it is more accurately called \"frosting\", \"spotting\" or \"flaking\" as opposed to fully scraping an accurate surface. Typically a scraped surface is scraped to highly accurate flatness and then \"frosting\" is applied over it for oil retention. It is claimed to stop the so-called \"stick-slip\" phenomenon where a machine member might move in a jerky fashion rather than moving smoothly, allowing vibration and chatter. \nSuch frosting will definitely increase oil retention but will also drastically reduce bearing area and capacity. There is no possibility of achieving hydrodynamic bearing performance on normal sliding machine ways. The velocity is far too low. Most of the time the ways will run under boundary lubrication conditions while at the highest speeds it might achieve mixed lubrication. This makes oil additives important in ways lubrication. However, this view is somewhat contradicted by the external link \"Scraping methods\". \nHand scraping leaves a distinctive pattern on the surface that is scraped. This can be suggestive of a high level of precision in the ways, however, sometimes a surface can be marked to appear hand scraped, but it is really just a superficial surface treatment designed to give the impression of a scraped machine way.\nHand scraping can also be done by a power tool that has a reciprocating blade and is usually adjustable for stroke length and number of strokes per minute.", "Engineering,_Manufacturing": 0.9987765551, "qwen": "Yes"}
{"id": "42418733", "revid": "43203147", "url": "https://en.wikipedia.org/wiki?curid=42418733", "title": "Hay's test", "text": "Hay's test, also known as Hay's sulphur powder test, is a chemical test used for detecting the presence of bile salts in urine.\nProcedure.\nSulphur powder is sprinkled into a test tube with three millilitres of urine and if the test is positive, the sulphur powder sinks to the bottom of the test tube. Sulphur powder sinks because bile salts decrease the surface tension of urine.", "Engineering,_Manufacturing": 0.9999952316, "qwen": "Yes"}
{"id": "42435212", "revid": "193417", "url": "https://en.wikipedia.org/wiki?curid=42435212", "title": "NATURTRUCK", "text": "NATURTRUCK is a European project whose main objective is to develop injected plastic parts for the commercial vehicles industry (mainly cabin truck parts) made with thermoplastic composite materials from renewable resources (modified polylactic acid and natural fibres), with improved thermal, flame retardancy properties and high quality surface finishing to be used in car internal parts. Those biocomposites are meant to be a real alternative to low-gloss standard ABS grades at a competitive cost.\nNATURTRUCK is addressed to allow SME’s partners, and consequently the EU industry, to fabricate new eco-friendly thermoplastic biocomposite products suitable to satisfy the commercial vehicles manufacture sector requirements, at a cost comparable to current ABS price, increasing their differentiation from competitors and creating significant market opportunities.\nPartners.\nNATURTRUCK consortium has been built up in order to join all the required technical and managerial expertise and capabilities and market complementarities and exploitation interests to streamline the achievement of Project results to solve the SME Participant (SMEP) needs and facilitate the exploitation of NATURTRUCK achievements, having representatives of the whole Project value chain. The consortium consists of 10 partners:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "42436351", "revid": "7949351", "url": "https://en.wikipedia.org/wiki?curid=42436351", "title": "Kennebunk Manufacturing Company", "text": "Kennebunk Manufacturing Company\nThe Kennebunk Manufacturing Company made cases, boxes, valises, grips, and trunks from 1893 to 1906 in Kennebunk, Maine and from 1906 to 1936 in Milton, New Hampshire.\nHistory.\nThe Kennebunk Manufacturing Company (KEMACO) was incorporated in Maine on July 23, 1893 with John R. Littlefield of Boston, Mass., President and J. B. Lara of Kennebunk, Me., Treasurer. The purpose of the Company was the “manufacturing and dealing in cases, boxes, valises, grips, and trunks.” The name, “Kennebunk Manufacturing Company” was the same name as that of an ill fated company that had tried to build a cotton mill at Kennebunk in 1825 and failed by 1828. The new Kennebunk Manufacturing Company merged with another Kennebunk manufacturer of similar travel items known as the Travelet Company after 1895. The merged companies were purchased by J. Spaulding & Sons Company in 1902 and its operations were moved to Milton, New Hampshire where they occupied the old N.B. Thayer & Co, shoe factory until 1936. While in Milton the Kennebunk Manufacturing Company, manufactured megaphones, radio speaker horns and violin cases in addition to its original line of lunch boxes and suit and sample cases. \nIn 1936 the operations of the Kennebunk Manufacturing Company were integrated with those of Spaulding & Perkins Company and the Spaulding Fibre Materials Handling Division was created at North Rochester, New Hampshire.", "Engineering,_Manufacturing": 0.9999841452, "qwen": "Yes"}
{"id": "42443688", "revid": "23914831", "url": "https://en.wikipedia.org/wiki?curid=42443688", "title": "Lead frame", "text": "A lead frame (pronounced ) is a metal structure inside a chip package that carries signals from the die to the outside, used in DIP, QFP and other packages where connections to the chip are made on its edges.\nThe lead frame consists of a central die pad, where the die is placed, surrounded by leads, metal conductors leading away from the die to the outside world. The end of each lead closest to the die ends in a bond pad. Small bond wires connect the die to each bond pad. Mechanical connections fix all these parts into a rigid structure, which makes the whole lead frame easy to handle automatically.\nManufacturing.\nLead frames are manufactured by removing material from a flat plate of copper, copper-alloy, or iron-nickel alloy like alloy 42. Two processes used for this are etching (suitable for high density of leads), or stamping (suitable for low density of leads). The mechanical bending process can be applied after both techniques.\nThe die is glued or soldered to the die pad inside the lead frame, and then bond wires are attached between the die and the bond pads to connect the die to the leads. In a process called encapsulation, a plastic case is moulded around the lead frame and die, exposing only the leads. The leads are cut off outside the plastic body and any exposed supporting structures are cut away. The external leads are then bent to the desired shape.\nUses.\nAmongst others, lead frames are used to manufacture a quad flat no-leads package (QFN), a quad flat package (QFP), or a dual in-line package (DIP).", "Engineering,_Manufacturing": 0.9999021292, "qwen": "Yes"}
{"id": "43452481", "revid": "10289486", "url": "https://en.wikipedia.org/wiki?curid=43452481", "title": "Corma Inc.", "text": "Corma Inc. is a manufacturer of corrugated plastic pipe production systems headquartered near Toronto, Canada. The company's headquarters and principal manufacturing plant are located in Concord, Ontario. Corma also maintains its own aluminum alloy foundry, located in Forest, Ontario, where it forms the mold blocks used in its corrugators.\nCorma is active in corrugated plastic pipe manufacturing and infrastructure projects in the developing world, particularly in established and emerging markets worldwide.\nHistory.\nCorma's first M600 corrugated plastic pipe-making machine, also known as a corrugator, was delivered to Akatherm in Saint John, New Brunswick, in 1974. In 1978, Corma applied for their first patents in double-wall pipe production and vacuum forming. Over the years Corma received patents for mold block technologies, Internal pipe cooling, inline coupling, and many other quality enhancing technologies. In total, Corma has applied for, and received, more than 300 patents since 1973.\nIn 2006, Corma established the Corma Shanghai Co. Ltd. sales/service office and manufacturing centre in the People's Republic of China. Corma Deutschland is expanded to become a full, sales and service center supporting customers in Europe, Africa and the Middle East.\nPatents.\nCorma Inc. holds over 300 patents related to corrugators. The company continues to defend its patents from infringement by other companies.", "Engineering,_Manufacturing": 0.9998677969, "qwen": "Yes"}
{"id": "43454397", "revid": "19531195", "url": "https://en.wikipedia.org/wiki?curid=43454397", "title": "Gear bearing", "text": "A gear bearing is a type of rolling-element bearing similar to an epicyclic gear. Gear bearings consist of a number of smaller 'satellite' gears which revolve around the center of the bearing along a track on the outsides of the internal and satellite gears, and on the inside of the external gear. Each gear is in between two concentric rings. Therefore, the widths of the satellite gears must all be the same.\nEngagement.\nIn order for the surfaces to provide efficient axial meshing, the teeth must either be beveled or made with engagement. This avoids misalignment, sticking, and reduces sliding friction in the bearing. For instance, the illustrations present implementations of bearing gears with beveled teeth and rollers on their adjacent end faces as well as a herringbone engagement to provide minimal axial shift due to opposite sloping teeth.\nWork.\nNeglecting clearance and assuming perfect accuracy, the engagement of bearing gears is aimed at maximum rolling with minimum sliding friction of conjugated profiles in movement. End rollers limit the gears radial shift at their contact points so that when the gears are engaged, slip-free rolling motion of their conjugated pairs is achieved. Adjacent end faces of teeth and rollers limit the axial shift of conjugated bearing gears in plane-parallel motion. In such a way, using bearing gears as sun, ring and more than two satellites uniformly distributed among them the entire gear bearing is arranged, and carrier may be used instead of ring or sun gearwheels, or it may act as a frame unit and transfer rotation from the satellites, whereas limitation of carrier degrees of freedom would form redundant constraints or serve as an additional basis for force distribution in the mechanism. In case less than three bearing satellite gearwheels are involved, at least axles of movable sun and/or of ring bearing gearwheels should be fixed relative to housing parts.\nUsage.\nGear bearings could be used as a more efficient bearing when used as a planetary gear arrangement with simplified kinematic relations and/or suspension. It also possible to use double row planetary gear combinations. In particular, systems of direct analog indications such as measuring instruments and planetary watches.\nLinear gear bearings can easily be made with straight tracks. One, cast in bronze, is used as the expansion joint in the centre of Kingsgate Bridge.\nImplementations.\nThe implementation of gear bearings may be one-piece manufacturing or a fixed joint assembly using: screws, bracers, threaded connections, pressure coupling, soldering, welding, gluing, or friction coupling in the form of sliding safety clutch or friction connection. The gear bearing may also be assembled from separate sectional parts or by joining with optional elastic and/or thermal deformation in the manufacturing sequence.", "Engineering,_Manufacturing": 0.9999461174, "qwen": "Yes"}
{"id": "2120748", "revid": "44120587", "url": "https://en.wikipedia.org/wiki?curid=2120748", "title": "Lapping", "text": "Lapping is a machining process in which two surfaces are rubbed together with an abrasive between them, by hand movement or using a machine.\nLapping often follows other subtractive processes with more aggressive material removal as a first step, such as milling and/or grinding. \nLapping can take two forms. The first type of lapping (traditionally often called grinding), involves rubbing a brittle material such as glass against a surface such as iron or glass itself (also known as the \"lap\" or grinding tool) with an abrasive such as aluminum oxide, jeweller's rouge, optician's rouge, emery, silicon carbide, diamond, etc., between them. This produces microscopic conchoidal fractures as the abrasive rolls about between the two surfaces and removes material from both.\nThe other form of lapping involves a softer material such as pitch or a ceramic for the lap, which is \"charged\" with the abrasive. The lap is then used to cut a harder material—the workpiece. The abrasive embeds within the softer material, which holds it and permits it to score across and cut the harder material. Taken to a finer limit, this will produce a polished surface such as with a polishing cloth on an automobile, or a polishing cloth or polishing pitch upon glass or steel.\nTaken to the ultimate limit, with the aid of accurate interferometry and specialized polishing machines or skilled hand polishing, lensmakers can produce surfaces that are flat to better than 30 nanometers. This is one twentieth of the wavelength of light from the commonly used 632.8 nm helium neon laser light source. Surfaces this flat can be molecularly bonded (optically contacted) by bringing them together under the right conditions. (This is not the same as the wringing effect of Johansson blocks, although it is similar).\nOperation.\nA piece of lead may be used as the lap, charged with emery, and used to cut a piece of hardened steel. The small plate shown in the first picture is a hand lapping plate. That particular plate is made of cast iron. In use, a slurry of emery powder would be spread on the plate and the workpiece simply rubbed against the plate, usually in a \"figure-eight\" pattern.\nThe second picture is of a commercially available lapping machine. The lap or lapping plate in this machine is in diameter, about the smallest size available commercially. At the other end of the size spectrum, machines with plates are not uncommon, and systems with tables in diameter have been constructed. Referring to the second picture again, the lap is the large circular disk on the top of the machine. On top of the lap are two rings. The workpiece would be placed inside one of these rings. A weight would then be placed on top of the workpiece. The weights can also be seen in the picture along with two fiber spacer disks that are used to even the load.\nIn operation, the rings stay in one location as the lapping plate rotates beneath them. In this machine, a small slurry pump can be seen at the side, this pump feeds abrasive slurry onto the rotating lapping plate.\nWhen there is a requirement to lap very small specimens (from down to a few millimetres), a lapping jig can be used to hold the material while it is lapped (see Image 3, Lapping machine and retention jig). A jig allows precise control of the orientation of the specimen to the lapping plate and fine adjustment of the load applied to the specimen during the material removal process. Due to the dimensions of such small samples, traditional loads and weights are too heavy as they would destroy delicate materials. The jig sits in a cradle on top of the lapping plate and the dial on the front of the jig indicates the amount of material removed from the specimen.\nTwo-piece lapping.\nWhere the mating of the two surfaces is more important than the flatness, the two pieces can be lapped together. The principle is that the protrusions on one surface will both abrade and be abraded by the protrusions on the other, resulting in two surfaces evolving towards some common shape (not necessarily perfectly flat), separated by a distance determined by the average size of the abrasive particles, with a surface roughness determined by the variation in the abrasive size. This yields closeness-of-fit results comparable to that of two accurately-flat pieces, without quite the same degree of testing required for the latter.\nOne complication in two-piece lapping is the need to ensure that neither piece flexes or is deformed during the process. As the pieces are moved past each other, part of each (some area near the edge) will be unsupported for some fraction of the rubbing movement. If one piece flexes due to this lack of support, the edges of the opposite piece will tend to dig depressions into it a short distance in from the edge, and the edges of the opposite piece are heavily abraded by the same action - the lapping procedure assumes roughly equal pressure distribution across the whole surface at all times, and will fail in this manner if the workpiece itself deforms under that pressure.\nAccuracy and surface roughness.\nLapping can be used to obtain a specific surface roughness; it is also used to obtain very accurate surfaces, usually very flat surfaces. Surface roughness and surface flatness are two quite different concepts.\nA typical range of surface roughness that can be obtained without resorting to special equipment would fall in the range of 1 to 30 units Ra (average roughness), usually microinches.\nSurface accuracy or flatness is usually measured in helium light bands (HLB), one HLB measuring about . Again, without resort to special equipment accuracies of 1 to 3 HLB are typical. Though flatness is the most common goal of lapping, the process is also used to obtain other configurations such as a concave or convex surface.\nMeasurement.\nFlatness.\nThe easiest method for measuring flatness is with a height gauge positioned on a surface plate. You must set up the part on three stands and find the minimum variation while adjusting them, just placing the part on the surface plate and using a dial indicator to find TIR on the opposite side of the part measures parallelism. Flatness is more easily measured with a co-ordinate measuring machine. But neither of these methods can measure flatness more accurately than about .\nAnother method that is commonly used with lapped parts is the reflection and interference of monochromatic light. A monochromatic light source and an optical flat are all that are needed. The optical flat – which is a piece of transparent glass that has itself been lapped and polished on one or both sides – is placed on the lapped surface. The monochromatic light is then shone down through the glass. The light will pass through the glass and reflect off the workpiece. As the light reflects in the gap between the workpiece and the polished surface of the glass, the light will interfere with itself creating light and dark fringes called Newton's rings. Each fringe – or band – represents a change of one half wavelength in the width of the gap between the glass and the workpiece. The light bands display a contour map of the surface of the workpiece and can be readily interpreted for flatness. In the past the light source would have been provided by a helium-neon lamp or tube, using the neon 632.8nm line,or mercury vapor green line but nowadays a more common source of monochromatic light is the low pressure sodium lamp. Today, Laser diodes and LEDs are used, both being inexpensive and narrow-band light sources. With semiconductor light sources, blue is an option, having a smaller wavelength than red.\nFor a more thorough description of the physics behind this measurement technique, see interference.\nRoughness.\nSurface roughness is defined by the minute variations in height of the surface of a given material or workpiece. The individual variances of the peaks and valleys are averaged (Ra value), or quantified by the largest difference from peak-to-valley (Rz). Roughness is usually expressed in microns. A surface that exhibits an Ra of 8 consists of peaks and valleys that average no more than 8 µm over a given distance. Roughness may be also measured by comparing the surface of the workpiece to a known sample. Calibration samples are available usually sold in a set and usually covering the typical range of machining operations from about 125 µm Ra to 1 µm Ra.\nSurface roughness is measured with a profilometer, an instrument that measures the minute variations in height of the surface of a workpiece.", "Engineering,_Manufacturing": 0.999869585, "qwen": "Yes"}
{"id": "2125485", "revid": "910180", "url": "https://en.wikipedia.org/wiki?curid=2125485", "title": "Industrial Ethernet", "text": "Industrial Ethernet (IE) is the use of Ethernet in an industrial environment with protocols that provide determinism and real-time control. Protocols for industrial Ethernet include EtherCAT, EtherNet/IP, PROFINET, POWERLINK, SERCOS III, CC-Link IE, and Modbus TCP. Many industrial Ethernet protocols use a modified Media Access Control (MAC) layer to provide low latency and determinism. Some microcontrollers such as Sitara provide industrial Ethernet support.\nIndustrial Ethernet can also refer to the use of standard Ethernet protocols with rugged connectors and extended temperature switches in an industrial environment, for automation or process control. Components used in plant process areas must be designed to work in harsh environments of temperature extremes, humidity, and vibration that exceed the ranges for information technology equipment intended for installation in controlled environments. The use of fiber-optic Ethernet variants reduces the problems of electrical noise and provides electrical isolation. \nSome industrial networks emphasized deterministic delivery of transmitted data, whereas Ethernet used collision detection which made transport time for individual data packets difficult to estimate with increasing network traffic. Typically, industrial uses of Ethernet employ full-duplex standards and other methods so that collisions do not unacceptably influence transmission times.\nApplication environment.\nIndustrial use requires consideration of the environment in which the equipment must operate. Factory equipment must tolerate a wider range of temperature, vibration, physical contamination and electrical noise than equipment installed in dedicated information-technology wiring closets. Since critical process control may rely on an Ethernet link, economic cost of interruptions may be high and high availability is therefore an essential criterion. Industrial Ethernet networks must interoperate with both current and legacy systems, and must provide predictable performance and maintainability. In addition to physical compatibility and low-level transport protocols, a practical industrial Ethernet system must also provide interoperability of higher levels of the OSI model. An industrial network must provide security both from intrusions from outside the plant, and from inadvertent or unauthorized use within the plant.\nWhen an industrial network must connect to an office network or external networks, a firewall system can be inserted to control exchange of data between the networks. This network separation preserves the performance and reliability of the industrial network.\nIndustrial environments are often much harsher, often subject to oil sprays, water sprays, and physical vibrations, so often industrial Ethernet requires a more rugged and watertight connector on one or both ends of the Cat 5 or Cat 6 cable, such as M12 connectors or M8 connectors, rather than the 8P8C connectors commonly used in homes and businesses.\nAdvantages and difficulties.\nProgrammable logic controllers (PLCs) communicate using one of several possible open or proprietary protocols, such as EtherNet/IP, EtherCAT, Modbus, Sinec H1, Profibus, CANopen, DeviceNet or FOUNDATION Fieldbus. The idea to use standard Ethernet makes these systems more interoperable.\nSome of the advantages over other types of industrial network include:\nDifficulties of using industrial Ethernet include:", "Engineering,_Manufacturing": 1.0000054836, "qwen": "Yes"}
{"id": "70665915", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=70665915", "title": "2003–04 Moldovan Cup", "text": "The 2003–04 Moldovan Cup was the 13th season of the Moldovan annual football cup competition. The competition ended with the final held on 30 May 2004.\nRound of 16.\nThe first legs were played on 1 October 2003. The second legs were played on 22 October 2003.\nQuarter-finals.\nThe first legs were played on 5 November 2003. The second legs were played on 13 November 2003.\nSemi-finals.\nThe first legs were played on 4 April 2004. The second legs were played on 14 April 2004.", "Engineering,_Manufacturing": 0.9990352392, "qwen": "Yes"}
{"id": "3210672", "revid": "26112263", "url": "https://en.wikipedia.org/wiki?curid=3210672", "title": "1986 FIFA World Cup qualification (CAF)", "text": "Listed below are the dates and results for the 1986 FIFA World Cup qualification rounds for the African zone (CAF). For an overview of the qualification rounds, see the article \"1986 FIFA World Cup qualification\".\nA total of 29 CAF teams entered the competition. The African Zone was allocated 2 places (out of 24) in the final tournament.\nFormat.\nThere would be four rounds of play:\nFirst round.\n\"Egypt won 2–1 on agg. and advanced to the Second Round.\"\n\"Kenya won 5–4 on agg. and advanced to the Second Round.\"\n\"Malawi won 5–0 on agg. and advanced to the Second Round.\"\n\"Zambia won 3–1 on agg. and advanced to the Second Round.\"\n\"Sudan advanced to the Second Round on away goals after a draw 1–1 on agg.\"\n\"Morocco won 5–0 on agg. and advanced to the Second Round.\"\n\"Tunisia won 6–0 on agg. and advanced to the Second Round.\"\n\"Ivory Coast won 6–3 on agg. and advanced to the Second Round.\"\n\"Nigeria won 4–0 on agg. and advanced to the Second Round.\"\n\"Angola advanced to the Second Round on penalties after a draw won 1–1 on agg.\"\n\"Madagascar advanced to the Second Round, Lesotho withdrew.\"\n\"Libya advanced to the Second Round, Niger withdrew.\"\n\"Guinea advanced to the Second Round, Togo withdrew.\"\nSecond round.\n\"Zambia won 5–2 on agg. and advanced to the Third Round.\"\n\"Morocco won 2–0 on agg. and advanced to the Third Round.\"\n\"Algeria won 3–2 on agg. and advanced to the Third Round.\"\n\"Nigeria won 6–1 on agg. and advanced to the Third Round.\"\n\"Egypt advanced to the Third Round on penalties after a draw 1–1 on agg.\"\n\"Tunisia won 2–1 on agg. and advanced to the Third Round.\"\n\"Libya won 4–0 on agg. and advanced to the Third Round.\"\n\"Ghana won 2–0 on agg. and advanced to the Third Round.\"\nThird round.\n\"Algeria won 3–0 on agg. and advanced to the Final Round.\"\n\"Libya won 2–0 on agg. and advanced to the Final Round.\"\n\"Tunisia won 2–1 on agg. and advanced to the Final Round.\"\n\"Morocco won 2–0 on agg. and advanced to the Final Round.\"\nFinal round.\n\"Algeria won 7–1 on agg. and qualified for the 1986 FIFA World Cup.\"\n\"Morocco won 3–1 on agg. and qualified for the 1986 FIFA World Cup.\"", "Engineering,_Manufacturing": 1.0000053644, "qwen": "Yes"}
{"id": "3210792", "revid": "25242445", "url": "https://en.wikipedia.org/wiki?curid=3210792", "title": "1982 FIFA World Cup qualification (CAF)", "text": "Listed below are the dates and results for the 1982 FIFA World Cup qualification rounds for the African zone (CAF). For an overview of the qualification rounds, see the article \"1982 FIFA World Cup qualification\".\nA total of 29 CAF teams entered the competition. However, Central African Republic was excluded by FIFA for not paying the entry fee. The African Zone was allocated 2 places (out of 24) in the final tournament. Finally 26 nations played at least one of the 46 games.\nFormat.\nThere would be four rounds of play:\nFirst round.\n\"Morocco won 1–0 on agg. and advanced to the Second Round.\"\n\"Zaire won 7–3 on agg. and advanced to the Second Round.\"\n\"Cameroon won 4–1 on agg. and advanced to the Second Round.\"\n\"Guinea won 4–2 on agg. and advanced to the Second Round.\"\n\"Nigeria won on penalties after 2–2 on agg. and so advanced to the Second Round.\"\n\"Libya won 2–1 on agg. and advanced to the Second Round.\"\n\"Zambia won 4–0 on agg. and advanced to the Second Round.\"\n\"Niger advanced to the Second Round due on away goals after 1–1 on agg.\"\n\"Algeria won 5–3 on agg. and advanced to the Second Round.\"\n\"Tanzania won 6–3 on agg. and advanced to the Second Round.\"\n\"Egypt advanced to the Second Round, Ghana withdrew.\"\n\"Madagascar advanced to the Second Round, Uganda withdrew.\"\nSecond round.\n\"Algeria won 3–1 on agg. and advanced to the Third Round.\"\n\"Niger advanced to the Third Round due on away goals after a draw 2–2 on agg.\"\n\"Guinea won 1–0 on agg. and advanced to the Third Round.\"\n\"Cameroon won 2–1 on agg. and advanced to the Third Round.\"\n\"Morocco won on penalties after a draw 2–2 on agg. and advanced to the Third Round.\"\n\"Nigeria won 3–1 on agg. and advanced to the Third Round.\"\n\"Zaire won 4–3 on agg. and advanced to the Third Round.\"\n\"Egypt advanced to the Third Round, Libya withdrew.\"\nThird round.\n\"Algeria won 4–1 on agg. and advanced to the Final Round.\"\n\"Nigeria won 2–1 on agg. and advanced to the Final Round.\"\n\"Morocco won 1–0 on agg. and advanced to the Final Round.\"\n\"Cameroon won 6–2 on agg. and advanced to the Final Round.\"\nFinal round.\nAlgeria won 4–1 on agg. and qualified for the 1982 FIFA World Cup.\nCameroon won 4–1 on agg. and qualified for the 1982 FIFA World Cup.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "36490885", "revid": "910180", "url": "https://en.wikipedia.org/wiki?curid=36490885", "title": "Lean CFP driven", "text": "Lean CFP (Complex Flow Production) Driven is a new approach which takes into account not only the widely implemented Lean manufacturing, but combines the principles of Lean with the Operating Curve, an approach based on the theoretical approach of queuing theory developed in academia in the 1970s. The goal of Lean CFP Driven is to eliminate waste in order to achieve higher quality, increase productivity and at the same time understand the relationship between utilization, lead time and variability in order to maximize performance within the semiconductor industry.\nLean CFP Driven – Lean Complex Flow Production Driven.\nBackground Semiconductor industry.\nThe semiconductor industry is one of the most productive and dynamic industries in the world. It faces a continuous and rapid advancement in technology which puts the companies under constant pressure to come up with superior and cheaper goods than those that were state-of-the-art only a few months ago. The market and development of the market is based on Moore's Law or More than Moore.\nCustomer demand in the semiconductor market evolves and changes at a swift pace which leads to the fact that a high level of flexibility is necessary to serve and meet the requirements of the customers. The semiconductor industry is furthermore very capital intensive based on the fact that the production equipment is highly complex, specialized and thus incredibly expensive. Challenges that the industry is facing are to continuously improve yield performance, achieve the highest possible return on the expensive equipment, speed and zero defects.\nLean CFP Driven and Traditional Lean.\nLean CFP Driven moves in a new direction from the traditional Lean because of the additional focus on utilization, cycle time and variability. The different characteristics of the semiconductor industry, e.g. production structure and production related costs compared to other industries, forms the need to approach the Lean philosophy in a new way in order to meet these specific characteristics.\nThere are five key characteristics for the semiconductor industry:\nThe complex production flow of a semiconductor fab is due to what is called a reentrance flow. A reentrant flow is a well-known attribute within a wafer fab and refers to the wafer visiting each tool not only once, but maybe 20 times during the course through the fab. To duplicate the expensive equipment and create a linear flow would make it even more challenging to get the highest possible return on the equipment and reach an optimized utilization of each tool, even though it results in a very complex production.\nThe reentrant flow does require a certain level of flexibility, which in terms of Lean, could be seen as muda (Waste). The necessary flexibility, also in order to meet fluctuations in customer demand, requires the companies to apply other tools to measure and forecast performance and this is what Lean CFP Driven provides to the Semiconductor Industry. Lean CFP Driven adds the Operating Curve to evaluate the factors \"utilization\", \"cycle time\" and \"variability\" which cannot be done through implementation of Traditional Lean.\nTypical tools within the Traditional Lean which are also included in the new approach of Lean CFP Driven are as follows:\nWhat distinguishes Lean CFP Driven from the traditional approach of Lean in terms of tools is that the new approach applies the tool Operating Curve in addition to the tools listed above. An example of how the Operating Curve could look like is shown in the figure below. The optimal operating point is indicated for different variabilities describing the non-uniformity of the production, formula_1. The great advantage of adding the Operating Curve tool is to maximize performance by optimizing both utilization and speed at the same time for the complex industry of Semiconductors by reducing the variability via the 4-partner method.\nThe Operating Curve is a tool initially developed in academia in the 1970s, based on the queuing theory, which uses the indicators Cycle Time and Utilization to benchmark and forecast a manufacturing line’s performance. The Operating Curve can be applied for different reasons, for example:\nThe Operating curve can be described by the following formula:\nformula_2\nwhere :\nThe flow factor can also be described as:\nformula_3\nWhere:", "Engineering,_Manufacturing": 1.0000082254, "qwen": "Yes"}
{"id": "18829879", "revid": "684386", "url": "https://en.wikipedia.org/wiki?curid=18829879", "title": "Mark XIII", "text": "Mark XIII or Mark 13 often refers to the 13th version of a product, frequently military hardware. \"Mark\", meaning \"model\" or \"variant\", can be abbreviated \"Mk.\" \nMark XIII or Mark 13 can specifically refer to:", "Engineering,_Manufacturing": 0.9837318063, "qwen": "Yes"}
{"id": "9126587", "revid": "1151717766", "url": "https://en.wikipedia.org/wiki?curid=9126587", "title": "Forging temperature", "text": "Forging temperature is the temperature at which a metal becomes substantially more soft, but is lower than the melting temperature, such that it can be reshaped by forging. Bringing a metal to its forging temperature allows the metal's shape to be changed by applying a relatively small force, without creating cracks. For most metals, forging temperature is approximately 70% of the absolute temperature (usually measured in kelvins) of its melting point.\nSelecting the maximum forging temperature allows metals to be forged more easily, lowering the forging pressure and thus the wear on metal-forming dies. The temperature at which a metal is forged can affect the homogeneity in microstructure and mechanical properties of forged products, which can highly affect the performance of products used in manufacturing.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1814324", "revid": "1142255671", "url": "https://en.wikipedia.org/wiki?curid=1814324", "title": "BSA Manufacturing", "text": "BSA Manufacturing Sdn Bhd formed in 1995, is a Malaysian manufacturer of aluminum alloy wheels. The company started as an importer of alloy wheels from Germany, Italy, England, Brazil, Japan, Thailand and Taiwan, and later manufactured its own products. The Company's line of business includes the manufacturing of motor vehicle parts and accessories \nBSA became the first Malaysian company to combine the use of Japanese technology with Hi-Tech Robotic Casting machine for alloy wheels manufacturing. Its alloy wheels are used in over 62 countries, including in Europe, North and South America.\nBSA sponsored Alex Yoong for his drive with the Minardi F1 team in 2002, along with other Malaysian companies.", "Engineering,_Manufacturing": 0.9998366237, "qwen": "Yes"}
{"id": "1816139", "revid": "5846", "url": "https://en.wikipedia.org/wiki?curid=1816139", "title": "Target costing", "text": "Target costing is an approach to determine a product's life-cycle cost which should be sufficient to develop specified functionality and quality, while ensuring its desired profit. It involves setting a target cost by subtracting a desired profit margin from a competitive market price. A target cost is the maximum amount of cost that can be incurred on a product, however, the firm can still earn the required profit margin from that product at a particular selling price. Target costing decomposes the target cost from product level to component level. Through this decomposition, target costing spreads the competitive pressure faced by the company to product's designers and suppliers. Target costing consists of cost planning in the design phase of production as well as cost control throughout the resulting product life cycle. The cardinal rule of target costing is to never exceed the target cost. However, the focus of target costing is not to minimize costs, but to achieve a desired level of cost reduction determined by the target costing process.\nDefinition.\nTarget costing is defined as \"a disciplined process for determining and achieving a full-stream cost at which a proposed product with specified functionality, performance, and quality must be produced in order to generate the desired profitability at the product’s anticipated selling price over a specified period of time in the future.\" This definition encompasses the principal concepts: products should be based on an accurate assessment of the wants and needs of customers in different market segments, and cost targets should be what result after a sustainable profit margin is subtracted from what customers are willing to pay at the time of product introduction and afterwards.\nThe fundamental objective of target costing is to manage the business to be profitable in a highly competitive marketplace. In effect, target costing is a proactive cost planning, cost management, and cost reduction practice whereby costs are planned and managed out of a product and business early in the design and development cycle, rather than during the later stages of product development and production.\nHistory.\nTarget costing was developed independently in both USA and Japan in different time periods. Target costing was adopted earlier by American companies to reduce cost and improve productivity, such as Ford Motor from 1900s, American Motors from 1950s-1960s. Although the ideas of target costing were also applied by a number of other American companies including Boeing, Caterpillar, Northern Telecom, few of them apply target costing as comprehensively and intensively as top Japanese companies such as Nissan, Toyota, Nippondenso. Target costing emerged from Japan from 1960s to early 1970s with the particular effort of Japanese automobile industry, including Toyota and Nissan. It did not receive global attention until late 1980s to 1990s when some authors such as Monden (1992), Sakurai (1989), Tanaka (1993), and Cooper (1992) described the way that Japanese companies applied target costing to thrive in their business (IMA 1994). With superior implementation systems, Japanese manufacturers are more successful than the American companies in developing target costing. Traditional cost-plus pricing strategy has been impeding the productivity and profitability for a long time. As a new strategy, target costing is replacing traditional cost-plus pricing strategy by maximizing customer satisfaction by accepted level of quality and functionality while minimizing costs.\nProcess of target costing.\nThe process of target costing can be divided into three sections: the first section involves in market-driven target costing, which focuses on studying market conditions to identify a product's allowable cost in order to meet the company's long-term profit at expected selling price; the second section involves performing cost reduction strategies with the product designer's effort and creativity to identify the product-level target cost; the third section is component-level target cost which decomposes the production cost to functional and component levels to transmit cost responsibility to suppliers.\nMarket-driven target costing.\nMarket driven target costing is the first section in the target costing process which focuses on studying market conditions and determining the company's profit margin in order to identify the allowable cost of a product. Market driven costing can go through 5 steps including: establish company's long-term sales and profit objective; develop the mix of products; identify target selling price for each product; identify profit margin for each product; and calculate allowable cost of each product.\nCompany's long-term sales and profit objectives are developed from an extensive analysis of relevant information relating to customers, market and products. Only realistic plans are accepted to proceed to the next step. Product mix is designed carefully to ensure that it satisfies many customers, but also does not contain too many products to confuse customers. Company may use simulation to explore the impact of overall profit objective to different product mixes and determine the most feasible product mix. Target selling price, target profit margin and allowable cost are identified for each product. Target selling price need to consider to the expected market condition at the time launching the product. Internal factors such as product's functionality and profit objective, and external factors such as company's image or expected price of competitive products will influence target selling price. Company's long-term profit plan and life-cycle cost are considered when determining target profit margin. Firms might set up target profit margin based on either actual profit margin of previous products or target profit margin of product line. Simulation for overall group profitability can help to make sure achieving group target. Subtracting target profit margin from target selling price results in allowable cost for each product. Allowable cost is the amount that can spent on a product to ensure its profit target is met if it is sold at its target price. It is the signal about the magnitude of cost saving that team need to achieve.\nProduct-level target costing.\nFollowing the completion of market-driven costing, the next task of the target costing process is product-level target costing. Product-level target costing concentrates on designing products that satisfy the company's customers at the allowable cost. To achieve this goal, product-level target costing is typically divided into three steps as shown below.\nThe first step is to set a product-level target cost. Since the allowable cost is simply obtained from external conditions without considering the design capabilities of the company as well as the realistic cost for manufacturing, it may not be always achievable in practice. Thus, it is necessary to adjust the unachievable allowable cost to an achievable target cost that the cost increase should be reduced with great effort. The second step is to discipline this target cost process, including monitoring the relationship between the target cost and the estimated product cost at any point during the design process, applying the cardinal rule so that the total target costs at the component-level does not exceed the target cost of the product, and allowing exceptions for products violating the cardinal rule. For a product exception to the cardinal rule, two analyses are often performed after the launch of the product. One involves reviewing the design process to find out why the target cost was unachieved. The other is an immediate effort to reduce the excessive cost to ensure that the period of violation is as short as possible. Once the target cost-reduction objective is identified, the product-level target costing comes to the final step, finding ways to achieve it. Engineering methods such as value engineering (VE), design for manufacture and assembly (DFMA), and quality function deployment (QFD) are commonly adopted in this step.\nTarget costing and value engineering.\nValue engineering (VE), also known as value analysis (VA), plays a crucial role in the target costing process, particularly at the product level and the component level. Among the three aforementioned methods in achieving the target cost, VE is the most critical one because not only does it attempt to reduce costs, but also aims to improve the functionality and quality of products. There are a variety of practical VE strategies, including zero-look, first-look and second-look VE approaches, as well as teardown approaches.\nRegarding the complexity of problems in the real world, implementing the target costing process often relies on the computer simulation to reproduce stochastic elements. For example, many firms use simulation to study the complex relationship between selling prices and profit margins, the impact of individual product decisions on overall group profitability, the right mix of products to enhance overall profit, or other economic modeling to overcome organizational inertia by getting the most productive reasoning. In addition, simulation helps estimate results rapidly for dynamic process changes.\nFactors affecting target costing.\nThe factors influencing the target costing process is broadly categorized based on how a company's strategy for a product's quality, functionality and price change over time. However, some factors play a specific role based on what drives a company's approach to target costing.\nFactors influencing market-driven costing.\nIntensity of competition and nature of the customer affect market-driven costing. Competitors introducing similar products has been shown to drive rival companies to expend energy on implementing target costing systems such as in the case of Toyota and Nissan or Apple and Google. The costing process is also affected by the level of customer sophistication, changing requirements and the degree to which their future requirements are known. The automotive and camera industry are prime examples for how customers affect target costing based on their exact requirements.\nFactors influencing product-level costing.\nProduct strategy and product characteristics affect product-level target costing. Characteristics of product strategy such as number of products in line, rate of redesign operations and level of innovation are shown to have an effect. Higher number of products has a direct correlation with the benefits of target costing. Frequent redesigns lead to the introduction of new products that have created better benefits to target costing. It has to be noted that the value of historical information reduces with greater innovation, thereby, reducing the benefits of product level target costing.\nThe degree of complexity of the product, level of investments required and the duration of product development process make up the factors that affect the target costing process based on product characteristics. Product viability is determined by the aforementioned factors. In turn, the target costing process is also modified to suit the different degrees of complexity required.\nFactors influencing component-level costing.\nSupplier-Base strategy is the main factor that determines component-level target costing because it is known to play a key role in the details a firm has about its supplier capabilities. There are three characteristics that make up the supplier-base strategy, including the degree of horizontal integration, power over suppliers and nature of supplier relations. Horizontal integration captures the fraction of product costs sourced externally. Cost pressures on suppliers can drive target costing if the buying power of firms is high enough. In turn, this may lead to better benefits. More cooperative supplier relations have been shown to increase mutual benefits in terms of target costs particularly at a component level.\nApplications.\nAside from the application of target costing in the field of manufacturing, target costing are also widely used in the following areas.\nEnergy.\nAn Energy Retrofit Loan Analysis Model has been developed using a Monte Carlo (MC) method for target costing in Energy Efficient buildings and construction. MC method has been shown to be effective in determining the impact of financial uncertainties in project performance.\nTarget Value Design Decision Making Process (TVD-DMP) groups a set of energy efficiency methods at different optimization levels to evaluate costs and uncertainties involved in the energy efficiency process. Some major design parameters are specified using this methods including Facility Operation Schedule, Orientation, Plug load, HVAC and lighting systems.\nThe entire process consists of three phases: initiation, definition and alignment. Initiation stage involves developing a business case for energy efficiency using target value design (TVD) training, organization and compensation. The definition process involves defining and validating the case by tools such as values analysis and bench marking processes to determine the allowable costs. By setting targets and designing the design process to align with those targets, TVD-DMP has been shown to achieve a high level of collaboration needed for energy efficiency investments. This is done by using risk analysis tools, pull planning and rapid estimating processes.\nHealthcare.\nTarget costing and target value design have applications in building healthcare facilities including critical components such as Neonatal Intensive Care Units (NICUs). The process is influenced by unit locations, degree of comfort, number of patients per room, type of supply location and access to nature. According to National Vital Statistics Reports, 12.18% of 2009 births were premature and the cost per infant was $51,600. This led to opportunities for NICUs to implement target value design for deciding whether to build a single-family room or more open-bay NICUs. This was achieved using set-based design analysis which challenges the designer to generate multiple alternatives for the same functionality. Designs are evaluated keeping in mind the requirements of the various stakeholders in the NICU including nurses, doctors, family members and administrators. Unlike linear point-based design, set-based design narrows options to the optimal one by eliminating alternatives simultaneously defined by user constraints.\nConstruction.\nAbout 15% construction project in Japan adopted target costing for their cost planning and management as recognized by Jacomit (2008). In the U.S., target costing research has been carried out within the framework of lean construction as target value design (TVD) method and have been disseminated widely over construction industry in recent years. Research has proven that if being applied systematically, TVD can deliver a significant improvement in project performance with average reduction of 15% in comparison with market cost.\nTVD in construction project considers the final cost of project as a design parameter, similar to the capacity and aesthetics requirements for the project. TVD requires the project team to develop a target cost from the beginning. The project team is expected not to design exceeding the target cost without the owner's approval, and must use different skills to maintain this target cost. In some cases, the cost can increase but the project team must commit to decrease and must try their best to decrease without impacting on other functions of the project.", "Engineering,_Manufacturing": 0.9984144568, "qwen": "Yes"}
{"id": "20384555", "revid": "1588193", "url": "https://en.wikipedia.org/wiki?curid=20384555", "title": "Weld nut", "text": "A weld nut is a special type of nut specifically designed to be welded to another object (spot welding). There are various types for different applications.\nTypes.\nThese nuts have a long threaded cylinder with a large circular base to make welding easy. They also sometimes have projections (known as weld nibs or bosses) to keep the nut from warping while welding with a high current.\nThese are very similar to the round base nuts, but with an obround, or slab shaped, base. These are used in channels, tubes, or other tight quarters.\nTab base nuts are designed for spot welding on flat workpieces. They have a locating boss around the threads to locate it in a pilot hole.\nThese nuts are very similar to standard square or hex nuts, but have a locating boss and welding projections. The bosses also keep weld spatter out of the threads.\nRetainer weld nuts, also known as bridge weld nuts, have a floating nut retained inside a retainer to compensate for inconsistencies. The retainer is welded to the work piece while the nut is allowed to float.\nTube end nuts are sized to fit into the end of standard sized tubing, thus creating a threaded tube from standard stock.\nDual hole or twin piloted nuts are designed for use where there is a need for tapped holes close together.\nFour Projection Weld Nuts\nFour projections designed to fuse simultaneously so each projection flows and seats properly. \nSingle Tab Weld Nuts\nSingle button projection weld nut for use on heavier gage materials.\nMaterial.\nThe vast majority of weld nuts are manufactured in low carbon steel or stainless steel. This is due to the methods currently available to spot weld or projection weld the hardware to joining material. Aftermarket products such as zinc plating are sometimes used to coat low carbon weld nuts giving it the rust resistant properties of stainless steel at a substantial cost saving.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "20385827", "revid": "20818275", "url": "https://en.wikipedia.org/wiki?curid=20385827", "title": "Staking (manufacturing)", "text": "Staking is the process of connecting two components by creating an interference fit between the two pieces. One workpiece has a hole in it while the other has a boss that fits within the hole. The boss is very slightly undersized so that it forms a slip fit. A staking punch is then used to expand the boss radially and to compress the boss axially so as to form an interference fit between the workpieces. This forms a permanent joint.\nThermoplastic staking.\nThermoplastic staking, also known as heat staking, is the same process except that it uses heat to deform the plastic boss, instead of cold forming. A plastic stud protruding from one component fits into a hole in the second component. The stud is then deformed through the softening of the plastic to form a head which mechanically locks the two components together. It is a versatile technique benefiting from being quick, economical and consistent. Unlike welding techniques, staking has the capacity to join plastics to other materials (e.g. metal, PCB's) in addition to joining like or dissimilar plastics, and it has the advantage over other mechanical joining methods in eliminating the need for consumables such as rivets and screws.\nTechnology.\nThermoplastic staking can be performed with a wide variety of technologies including:", "Engineering,_Manufacturing": 0.9992768168, "qwen": "Yes"}
{"id": "1086236", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=1086236", "title": "Stereolithography", "text": "Stereolithography (SLA or SL; also known as vat photopolymerisation, optical fabrication, photo-solidification, or resin printing) is a form of 3D printing technology used for creating models, prototypes, patterns, and production parts in a layer by layer fashion using photochemical processes by which light causes chemical monomers and oligomers to cross-link together to form polymers. Those polymers then make up the body of a three-dimensional solid. Research in the area had been conducted during the 1970s, but the term was coined by Chuck Hull in 1984 when he applied for a patent on the process, which was granted in 1986. Stereolithography can be used to create prototypes for products in development, medical models, and computer hardware, as well as in many other applications. While stereolithography is fast and can produce almost any design, it can be expensive.\nHistory.\nStereolithography or \"SLA\" printing is an early and widely used 3D printing technology. In the early 1980s, Japanese researcher Hideo Kodama first invented the modern layered approach to stereolithography by using ultraviolet light to cure photosensitive polymers. In 1984, just before Chuck Hull filed his own patent, Alain Le Mehaute, Olivier de Witte and Jean Claude André filed a patent for the stereolithography process. The French inventors' patent application was abandoned by the French General Electric Company (now Alcatel-Alsthom) and CILAS (The Laser Consortium). Le Mehaute believes that the abandonment reflects a problem with innovation in France.\nThe term “stereolithography” (Greek: stereo-solid and lithography) was coined in 1984 by Chuck Hull when he filed his patent for the process. Hull patented stereolithography as a method of creating 3D objects by successively \"printing\" thin layers of an object using a medium curable by ultraviolet light, starting from the bottom layer to the top layer. Hull's patent described a concentrated beam of ultraviolet light focused onto the surface of a vat filled with a liquid photopolymer. The beam is focused onto the surface of the liquid photopolymer, creating each layer of the desired 3D object by means of crosslinking (generation of intermolecular bonds in polymers). It was invented with the intent of allowing engineers to create prototypes of their designs in a more time effective manner. After the patent was granted in 1986, Hull co-founded the world's first 3D printing company, 3D Systems, to commercialize it.\nStereolithography's success in the automotive industry allowed 3D printing to achieve industry status and the technology continues to find innovative uses in many fields of study. Attempts have been made to construct mathematical models of stereolithography processes and to design algorithms to determine whether a proposed object may be constructed using 3D printing.\nTechnology.\nStereolithography is an additive manufacturing process that, in its most common form, works by focusing an ultraviolet (UV) laser on to a vat of photopolymer resin. With the help of computer aided manufacturing or computer-aided design (CAM/CAD) software, the UV laser is used to draw a pre-programmed design or shape on to the surface of the photopolymer vat. Photopolymers are sensitive to ultraviolet light, so the resin is photochemically solidified and forms a single layer of the desired 3D object. Then, the build platform lowers one layer and a blade recoats the top of the tank with resin. This process is repeated for each layer of the design until the 3D object is complete. Completed parts must be washed with a solvent to clean wet resin from their surfaces.\nIt is also possible to print objects \"bottom up\" by using a vat with a transparent bottom and focusing the UV or deep-blue polymerization laser upward through the bottom of the vat. An inverted stereolithography machine starts a print by lowering the build platform to touch the bottom of the resin-filled vat, then moving upward the height of one layer. The UV laser then writes the bottom-most layer of the desired part through the transparent vat bottom. Then the vat is \"rocked\", flexing and peeling the bottom of the vat away from the hardened photopolymer; the hardened material detaches from the bottom of the vat and stays attached to the rising build platform, and new liquid photopolymer flows in from the edges of the partially built part. The UV laser then writes the second-from-bottom layer and repeats the process. An advantage of this bottom-up mode is that the build volume can be much bigger than the vat itself, and only enough photopolymer is needed to keep the bottom of the build vat continuously full of photopolymer. This approach is typical of desktop SLA printers, while the right-side-up approach is more common in industrial systems.\nStereolithography requires the use of supporting structures which attach to the elevator platform to prevent deflection due to gravity, resist lateral pressure from the resin-filled blade, or retain newly created sections during the \"vat rocking\" of bottom up printing. Supports are typically created automatically during the preparation of CAD models and can also be made manually. In either situation, the supports must be removed manually after printing.\nOther forms of stereolithography build each layer by LCD masking, or using a DLP projector.\nMaterials.\nThe liquid materials used for SLA printing are commonly referred to as \"resins\" and are thermoset polymers. A wide variety of resins are commercially available and it is also possible to use homemade resins to test different compositions for example. Material properties vary according to formulation configurations: \"materials can be soft or hard, heavily filled with secondary materials like glass and ceramic, or imbued with mechanical properties like high heat deflection temperature or impact resistance\". Recently, some studies have tested the possibility to green or reusable materials to produce \"sustainable\" resins. It is possible to classify the resins in the following categories:\nUses.\nMedical modeling.\nStereolithographic models have been used in medicine since the 1990s, for creating accurate 3D models of various anatomical regions of a patient, based on data from computer scans. Medical modelling involves first acquiring a CT, MRI, or other scan. This data consists of a series of cross sectional images of the human anatomy. In these images different tissues show up as different levels of grey. Selecting a range of grey values enables specific tissues to be isolated. A region of interest is then selected and all the pixels connected to the target point within that grey value range are selected. This enables a specific organ to be selected. This process is referred to as segmentation. The segmented data may then be translated into a format suitable for stereolithography. While stereolithography is normally accurate, the accuracy of a medical model depends on many factors, especially the operator performing the segmentation correctly. There are potential errors possible when making medical models using stereolithography but these can be avoided with practice and well trained operators.\nStereolithographic models are used as an aid to diagnosis, preoperative planning and implant design and manufacture. This might involve planning and rehearsing osteotomies, for example. Surgeons use models to help plan surgeries but prosthetists and technologists also use models as an aid to the design and manufacture of custom-fitting implants. For instance, medical models created through stereolithography can be used to help in the construction of Cranioplasty plates.\nIn 2019, scientists at Rice University published an article in the journal \"Science\", presenting soft hydrogel materials for stereolithography used in biological research applications.\nPrototyping.\nStereolithography is often used for prototyping parts. For a relatively low price, stereolithography can produce accurate prototypes, even of irregular shapes. Businesses can use those prototypes to assess the design of their product or as publicity for the final product.\nAdvantages and disadvantages.\nAdvantages.\nOne of the advantages of stereolithography is its speed; functional parts can be manufactured within a day. The length of time it takes to produce a single part depends upon the complexity of the design and the size. Printing time can last anywhere from hours to more than a day. Prototypes and designs made with stereolithography are strong enough to be machined and can also be used to make master patterns for injection molding or various metal casting processes.\nDisadvantages.\nAlthough stereolithography can be used to produce virtually any synthetic design, it is often costly, though the price is coming down. Since 2012, however, public interest in 3D printing has inspired the design of several consumer SLA machines which can cost considerably less.\nBeginning in 2016, substitution of the SLA and DLP methods using a high resolution, high contrast LCD panel has brought prices down to below 200. The layers are created in their entirety since the entire layer is displayed on the LCD screen and is exposed using UV LEDs that lie below. Resolutions of .01mm are attainable.\nAnother disadvantage is that the photopolymers are sticky, messy, and need to be handled with care. Newly made parts need to be washed, further cured, and dried. The environmental impact of all these processes requires more study to be understood, but in general SLA technologies have not created any biodegradable or compostable forms of resin, while other 3-D printing methods offer some compostable PLA options.", "Engineering,_Manufacturing": 0.9965417981, "qwen": "Yes"}
{"id": "4883560", "revid": "17601463", "url": "https://en.wikipedia.org/wiki?curid=4883560", "title": "Investment casting", "text": "Investment casting is an industrial process based on lost-wax casting, one of the oldest known metal-forming techniques. The term \"lost-wax casting\" can also refer to modern investment casting processes.\nInvestment casting has been used in various forms for the last 5,000 years. In its earliest forms, beeswax was used to form patterns necessary for the casting process. Today, more advanced waxes, refractory materials and specialist alloys are typically used for making patterns. Investment casting is valued for its ability to produce components with accuracy, repeatability, versatility and integrity in a variety of metals and high-performance alloys.\nThe fragile wax patterns must withstand forces encountered during the mould making. Much of the wax used in investment casting can be reclaimed and reused. Lost-foam casting is a modern form of investment casting that eliminates certain steps in the process.\nInvestment casting is so named because the process invests (surrounds) the pattern with refractory material to make a mould, and a molten substance is cast into the mold. Materials that can be cast include stainless steel alloys, brass, aluminium, carbon steel and glass. The cavity inside the refractory mould is a slightly oversized but otherwise exact duplicate of the desired part. Due to the hardness of refractory materials used, investment casting can produce products with exceptional surface qualities, which can reduce the need for secondary machine processes.\nWater glass and silica sol investment casting are the two primary investment casting methods currently in use. The main differences are the surface roughness and cost of casting. Water glass method dewaxes into the high-temperature water, and the ceramic mould is made of water glass quartz sand. Silica sol method dewaxes into the flash fire, and silica sol zircon sand makes the ceramic mould. Silica sol method costs more but has the better surface than the water glass method.\nThe process can be used for both small castings of a few ounces and large castings weighing several hundred pounds. It can be more expensive than die casting or sand casting, but per-unit costs decrease with large volumes. Investment casting can produce complicated shapes that would be difficult or impossible with other casting methods. It can also produce products with exceptional surface qualities and low tolerances with minimal surface finishing or machining required.\nProcess.\nCastings can be made from an original wax model (the direct method) or from wax replicas of an original pattern that need not be made from wax (the indirect method). The following steps describe the indirect process, which can take two to seven days to complete.\nDisadvantages.\nThe main disadvantage is the overall cost, especially for short-run productions. Some of the reasons for the high cost include specialized equipment, costly refractories, and binders, many operations to make a mould, a lot of labor is needed and occasional minute defects occur. However, the cost is still less than producing the same part by machining from bar stock; for example, gun manufacturing has moved to investment casting to lower costs of producing pistols.\nAdditionally:\nCounter-gravity casting.\nThe variation on the gravity pouring technique is to fill the mould using a vacuum. A common form of this is called the \"Hitchiner\" process after the Hitchiner Manufacturing Company that invented the technique. In this technique, the mould has a downward fill pipe that is lowered into the melt. A vacuum draws the melt into the cavity; when the important parts have solidified, the vacuum is released, and the unused material leaves the mould. The technique can use substantially less material than gravity pouring because the sprue and some gating need not solidify.\nThis technique is more metal efficient than traditional pouring because less material solidifies in the gating system. Gravity pouring only has a 15 to 50% metal yield compared to 60 to 95% for counter-gravity pouring. There is also less turbulence, so the gating system can be simplified since it does not have to control turbulence. The metal is drawn from below the top of the pool, so the metal is free from dross and slag (which are lower density (lighter) and float to the top of the pool). The pressure differential helps the metal flow into every intricacy of the mould. Finally, lower temperatures can be used, which improves the grain structure.\nThis process is also used to cast refractory ceramics under the term \"vacuum casting\".\nVacuum pressure casting.\n\"Vacuum pressure casting\" (\"VPC\"), properly referred to as \"vacuum assist direct pour\", uses gas pressure and a vacuum to improve the quality of the casting and minimize porosity. Typically VPC machines consist of an upper and a lower chamber—the upper chamber, or melting chamber, housing the crucible, and the lower casting chamber housing the investment mould. Both chambers are connected via a small hole containing a stopper. A vacuum is pulled in the lower chamber, while pressure is applied in the upper, and then the stopper is removed. This creates the greatest pressure differential to fill the moulds. The most common materials for \"vacuum casting process\" are the high nickel-based alloy and super alloys. Turbocharger products are a common applications for this casting process, though it is also regularly used in the manufacture of silver and gold jewellery.\nDetails.\nInvestment casting is used with almost any castable metal. However, aluminium alloys, copper alloys, and steel are the most common. In industrial use, the size limits are to several hundred kilograms. The cross-sectional limits are to . Typical tolerances are 0.1 mm for the first 25 mm (0.005 in for the first inch) and 0.02 mm for the each additional centimeter (0.002 in for each additional inch). A standard surface finish is 1.3–4 micrometres (50–125 μin) RMS.\nHistory.\nThe history of lost-wax casting dates back thousands of years. Its earliest use was for idols, ornaments and jewellery, using natural beeswax for patterns, clay for the moulds and manually operated bellows for stoking furnaces. Examples have been found across the world, such as in the Harappan Civilisation (2500–2000 BC) idols, Egypt's tombs of Tutankhamun (1333–1324 BC), Mesopotamia, Aztec and Mayan Mexico, and the Benin civilization in Africa where the process produced detailed artwork of copper, bronze and gold. By far, one of the earliest identified uses of the investment casting process was seen in objects found in the 'Cave of Treasure', discovered in Southern Israel. These items were identified as being made around 3700 BC using Carbon-14 dating techniques.\nThe earliest known text that describes the investment casting process (Schedula Diversarum Artium) was written around 1100 A.D. by Theophilus Presbyter, a monk who described various manufacturing processes, including the recipe for parchment. This book was used by sculptor and goldsmith Benvenuto Cellini (1500–1571), who detailed in his autobiography the investment casting process he used for the Perseus with the Head of Medusa sculpture that stands in the Loggia dei Lanzi in Florence, Italy.\nInvestment casting came into use as a modern industrial process in the late 19th century, when dentists began using it to make crowns and inlays, as described by Barnabas Frederick Philbrook of Council Bluffs, Iowa in 1897. Its use was accelerated by William H. Taggart of Chicago, whose 1907 paper described his development of a technique. He also formulated a wax pattern compound of excellent properties, developed an investment material, and invented an air-pressure casting machine.\nIn the 1940s, World War II increased the demand for precision net shape manufacturing and specialized alloys that could not be shaped by traditional methods, or that required too much machining. Industry turned to investment casting. After the war, its use spread to many commercial and industrial applications that used complex metal parts.\nApplications.\nInvestment casting is used in the aerospace and power generation industries to produce turbine blades with complex shapes or cooling systems. Blades produced by investment casting can include single-crystal (SX), directionally solidified (DS), or conventional equiaxed blades.\nInvestment casting is also widely used by firearms manufacturers to fabricate firearm receivers, triggers, hammers, and other precision parts at low cost.\nKarsten Solheim famously revolutionized golf club design through his company PING by incorporating investment casting for the first time for clubheads. Quickly the process became an industry standard to allow weight distribution around the perimeter of the clubhead.\nOther industries that use standard investment-cast parts include military, aerospace, medical, jewelry, airline, automotive and golf clubs especially since the start of 3D printing technology.\nWith the increased availability of higher-resolution 3D printers, 3D printing has begun to be used to make much larger sacrificial moulds used in investment casting. Planetary Resources has used the technique to print the mould for a new small satellite, which is then dipped in ceramic to form the investment cast for a titanium space bus with integral propellant tank and embedded cable routing.", "Engineering,_Manufacturing": 1.0000009537, "qwen": "Yes"}
{"id": "43831731", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=43831731", "title": "Sheet metal forming simulation", "text": "Today the metal forming industry is making increasing use of simulation to evaluate the performing of dies, processes and blanks prior to building try-out tooling. Finite element analysis (FEA) is the most common method of simulating sheet metal forming operations to determine whether a proposed design will produce parts free of defects such as fracture or wrinkling.\nSheet metal forming challenges.\nSheet metal forming, which is often referred to as stamping, is a process in which a piece of sheet metal, referred to as the blank, is formed by stretching between a punch and a die.\nThe most painful and most frequent defects are wrinkles, thinning, springback and splits or cracks. Few methods are being used around the industry to cope with the main defects, based on the experience of the technicians. However, the correct process is the most vital, since it involves the correct geometry followed by number of steps to reach at final geometry. Which demands for specific experience or higher number of iterations.\nDeformation of the blank is typically limited by buckling, wrinkling, tearing, and other negative characteristics which makes it impossible to meet quality requirements or makes it necessary to run at a slower than desirable rate.\nWrinkling in a draw are series of ridges form radially in the drawn wall due to compressive buckling. Practically these are duo to low blank holder pressure due to which material slips and wrinkles formed. The optimum blank holding pressure is the key, however in certain cases it doesn't work. Then draw beads are the solutions, the location and shape of draw bead is the challenge, which can be analysed with FEA during design stage prior to tool manufacturing.\nCrack in the vertical wall due to high tensile stresses, some small radius block the material flow and results in excessive thinning at that point usually more than 40% of the sheet thk. result in cracks. In some cases it may happen due to excessive blank holder pressure, which restrict the metal flow. Somewhere it might be due to wrong process design, like try to make a more deep draws in a single stage, which otherwise feasible only in two stages.\nThinning is a Excessive Stretching in the vertical wall due to high tensile stresses cause thickness reduction specifically on the small radius in the metal parts, however up to 20% thinning is allowed due to process limitations.\nSpringback is a particularly critical aspect of sheet metal forming. Even relatively small amounts of springback in structures that are formed to a significant depth may cause the blank to distort to the point that tolerances cannot be held. New materials such as high strength steel, aluminum and magnesium are particularly prone to springback.\nSheet metal forming is more of an art than a science. The design of the tooling, stamping process and blank materials and geometry are primarily done by trial and error.\nNowadays the simulation software's comes under CAE (computer aided engineering), used the finite element analysis to predict the common defects in design stage, prior to die manufacturing.\nThe traditional approach to designing the punch and die to produce parts successfully is to build try-out tools to check the ability of a certain tool design to produce parts of the required quality. Try-out tools are typically made of less expensive materials to reduce try-out costs yet this method is still costly and time-consuming.\nHistory of sheet metal forming simulation.\nThe first effort at simulating metalforming was made using the finite difference method in the 1960s to better understand the deep drawing process. Simulation accuracy was later increased by applying nonlinear finite element analysis in the 1980s but computing time was too long at this time to apply simulation to industrial problems.\nRapid improvements over the past few decades in computer hardware have made the finite element analysis method practical for resolving real-world metal forming problems. A new class of FEA codes based on explicit time integration was developed that reduced computational time and memory requirements. The dynamic explicit FEA approach uses a central different explicit scheme to integrate the equations of motion. This approach uses lumped mass matrices and a typical time step on order of millionths of seconds. The method has proved to be robust and efficient for typical industrial problems.\nAs computer hardware and operating systems have evolved, memory limitations that prevented the practical use of Implicit Finite Element Methods had been overcome. Using the implicit method time steps are computed based on the predicted amount of deformation occurring at a given moment in the simulation, thus preventing unnecessary computational inefficiency caused by computing too small time steps when nothing is happening or too large a time step when high amounts of deformation are occurring.\nFinite Element Analysis Methods.\nTwo broad divisions in the application of Finite Element Analysis method for sheet metal forming can be identified as Inverse One-step and Incremental.\nInverse One-step methods compute the deformation potential of a finished part geometry to the flattened blank. Mesh initially with the shape and material characteristics of the finished geometry is deformed to the flat pattern blank. The strain computed in this inverse forming operation is then inverted to predict the deformation potential of the flat blank being deformed into the final part shape. All the deformation is assumed to happen in one increment or step and is the inverse of the process which the simulation is meant to represent, thus the name Inverse One-Step.\nIncremental Analysis methods start with the mesh of the flat blank and simulate the deformation of the blank inside of tools modeled to represent a proposed manufacturing process. This incremental forming is computed \"forward\" from initial shape to final, and is calculated over a number of time increments for start to finish. The time increments can be either explicitly or implicitly defined depending on the finite element software being applied. As the incremental methods include the model of the tooling and allow for the definition of boundary conditions which more fully replicate the manufacturing proposal, incremental methods are more commonly used for process validation. Inverse One-step with its lack of tooling and therefore poor representation of process is limited to geometry based feasibility checks.\nIncremental analysis has filled the role previously completed through the use of proof tools or prototype tools. Proof tools in the past were short run dies made of softer than normal material, which were used to plan and test the metal forming operations. This process was very time consuming and did not always yield beneficial results, as the soft tools were very different in their behavior than the longer running production tools. Lessons learned on the soft tools did not transfer to the hard tool designs. Simulation has for the most part displaced this old method. Simulation used as a virtual tryout is a metal forming simulation based on a specific set of input variables, sometimes nominal, best case, worst case, etc. However, any simulation is only as good as the data used to generate the predictions. When a simulation is seen as a \"passing result\" manufacturing of the tool will often begin in earnest. But if the simulation results are based on an unrealistic set of production inputs then its value as an engineering tool is suspect.\nRobustness Analysis.\nRecent innovations in stochastic analysis applied to sheet metal forming simulations has enabled early adopters to engineer repeat-ability into their processes that might not be found if they are using single sets of simulations as \"virtual tryout\".\nUses of sheet metal forming simulation.\nChaboche type material models are sometimes used to simulate springback effects in sheet metal forming. These and other advanced plasticity models require the experimental determination of cyclic stress-strain curves. Test rigs have been used to measure material properties that when used in simulations provide excellent correlation between measured and calculated springback.\nMany metal forming operation require too much deformation of the blank to be performed in a single step. Multistep or progressive stamping operations are used to incrementally form the blank into the desired shape through a series of stamping operations. Incremental forming simulation software platforms addresses these operations with a series of one-step stamping operations that simulate the forming process one step at a time.\nAnother common goal in design of metal forming operations is to design the shape of the initial blank so that the final formed part requires few or no cutting operations to match the design geometry. The blank shape can also be optimized with finite element simulations. One approach is based on an iterative procedure that begins with an approximate starting geometry, simulates the forming process and then checks deviation of the resulting formed geometry from the ideal product geometry. The node points are adjusted in accordance with the displacement filed to correct the blank edge geometry. This process is continued until the end blank shape matches the as-designed part geometry.\nMetal forming simulation offers particular advantages in the case of high strength steel and advanced high-strength steel which are used in current day automobiles to reduce weight while maintaining crash safety of the vehicle. The materials have higher yield and tensile strength than conventional steel so the die undergoes greater deformation during the forming process which in turn increases the difficulty of designing the die. Sheet metal simulation that considers the deformation of not only the blank but also the die can be used to design tools to successfully form these materials.\nIndustrial applications.\nTata Motors engineers used metal forming simulation to develop tooling and process parameters for producing a new oil pump design. The first prototypes that were produced closed matched the simulation prediction.\nNissan Motor Company used metal forming simulation to address a tearing problem in a metal stamping operation. A simple simulation model was created to determine the effect of blank edge radius on the height to which the material could be formed without tearing. Based on this information a new die was designed that solved the problem.\nThere are lots of sheet metal programs available in the industry as SolidWorks and LITIO.\nNowadays FEA software's such as LS DYNA, AUTOFORM, HYPERFORM, PAMSTAMP are very good for virtual process simulations prior to product manufacturing. The defects such as Wrinkles, thinning and cracks can be seen in the design stage right just before the process design, results in correct process selection and reduction in lead time and save valuable money, which otherwise invested in hectic manufacturing iterations.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "43967705", "revid": "45993554", "url": "https://en.wikipedia.org/wiki?curid=43967705", "title": "TRI-D (rocket engine)", "text": "TRI-D is a 3D printed metal rocket engine. Students from the Students for the Exploration and Development of Space at University of California, San Diego (SEDS at UC San Diego) built the metal rocket engine using a technique previously confined to NASA, using a GPI Prototype and Manufacturing Services printer via the Direct metal laser sintering (DMLS) method. UCSD students were the first group in the world to 3D print a rocket engine of its size, other than NASA as of February 2014. The Tri-D engine cost US$6,800.\nDevelopment.\nThe Tri-D rocket engine was designed and built with the cooperation of NASA’s Marshall Space Flight Center, to explore the feasibility of printed rocket components. It was designed to power the third stage of a Nanosat or Cubesat launcher, i.e. an engine capable of launching satellites that weigh less than 1.33 kg (2.93 lb).\nSpecifications.\nTri-D is around 17.7 cm long and weighs around 4.5 kg. It was fabricated using a chromium-cobalt alloy powder. The propellants are kerosene and liquid oxygen. The engine produces about thrust. According to Gizmag \"the injector has a Fuel-Oxidizer-Oxidizer-Fuel inlet arrangement with two outer fuel orifices converging with two inner oxidizer orifices\".\nThe engine has a regenerative cooling jacket that extends to the nozzle to prevent the engine from overheating while firing. The combustion chamber was designed to burn the propellants in the middle of the chamber and keep as much heat generated as possible away from its chamber walls, while at the same time insulating the wall with a film of cooler gases.\nPrinter.\nThe engine was printed with a GPI Prototype and Manufacturing Services printer using a technique called Direct metal laser sintering (DMLS). In the process of printing, a powder of the chromium-cobalt alloy is spread in a thin layer. Then computer-controlled laser fuses the powders into a cross section of the engine component. The machine then spreads a second layer of powder and the process continuously repeats until each component is complete. Any excess powder is removed as are temporary supports that were printed to hold the components together during printing process. Finally it is hardened, polished and assembled.\nTest firing.\nThe test firing at Mojave went without any problems and the engine exhaust achieved thrust. The team claimed \"it was a resounding success and could be the next step in the development of cheaper propulsion systems and a commercializing of space\".\nInjector test.\nOn a separate engine, a 3D printed injector was test fired in a conventionally manufactured engine. In the test of the injector on August 22, 2014, the engine generated thrust.", "Engineering,_Manufacturing": 1.0000033379, "qwen": "Yes"}
{"id": "43968186", "revid": "41807748", "url": "https://en.wikipedia.org/wiki?curid=43968186", "title": "Solid Concepts 1911 DMLS", "text": "The Solid Concepts 1911 DMLS is a 3D printed improvised firearm version of the M1911 pistol. It was made public around November 2013 and was printed via the direct metal laser sintering (DMLS) method. It was created by Solid Concepts. The first gun, version 1.0, is made up of 34 3D-printed 17-4 stainless steel components.\nSpecifications.\nIt weighs when it is empty i.e is not filled with a magazine and the trigger pull weighs . The width is wide. The sight radius is and consists of a standard GI with a square notch rear. The ratio of the twist is 1:15.8; at 6=Lands 6=Grooves. The gun used Inconel 625 (a nickel-chromium alloy) material and stainless steel via the Direct Metal Laser Sintering method.\nThe Solid Concepts Browning M1911 replica, version 2.0, will be composed of 34 Inconel 625 components, (not including grips). The two carbon-fiber filled nylon 12 grips were also 3D printed. Unlike early 3D printed plastic guns, the barrel of the 1911 was rifled. None of the parts were machined during production, and assembly took less than seven minutes once the parts had been filed and hardened.\nPrinter.\nThe German EOSINT M270 Direct Metal 3D Printer used to create the weapon cost between $500,000 to $1,000,000 at the time the gun was created as of November 2013 and uses a commercial-grade power source. The printer requires argon and nitrogen gas\nCapability and firing tests.\nAccording to Sky News, during the initial test Solid Concepts stated: \"It functions beautifully. Our resident gun expert has fired 50 successful rounds and hit a few bull's eyes at over 30 yards (27.43 metres)\". \nThe Solid Concepts Pistol fired its 5000th round on 6 September 2014.", "Engineering,_Manufacturing": 0.9830319881, "qwen": "Yes"}
{"id": "43996164", "revid": "9945971", "url": "https://en.wikipedia.org/wiki?curid=43996164", "title": "Chrysler Valiant (AP6)", "text": "The Chrysler Valiant AP6 is an automobile which was produced by Chrysler Australia from 1965 to 1966. It was the fourth Chrysler Valiant model produced in Australia.\nOverview.\nThe Valiant AP6 was released in March 1965, replacing the Chrysler Valiant AP5. The basic styling was carried over from the AP5 but differed in having a new split grille, a new bonnet and new front mudguards. Mechanical changes included a redesigned camshaft, the introduction of self-adjusting brakes and the replacement of the push button gear selector on models with automatic transmission by a traditional lever system. Optional power brakes were made available across the range.\nA coupe utility variant was added to the range in April 1965 and marketed as the Valiant Wayfarer. This was the first Valiant-based coupe utility to be produced by Chrysler Australia.\nAs with the previous AP5 model, station wagon rear styling varied depending on production dates. Early build wagons used 1965 US Plymouth Valiant wagon-style tail lights. At some time in the production run Chrysler Australia invested in new tooling for the wagon rear sheet metal, allowing the use of sedan rear doors. Later style wagons again used vertical style tail lights. The new pressings required revised rear cargo area side windows and rear bumpers were also redesigned. Changes occurred from build number AP6-2W-3107 (manual Safari), AP6-4W-2167 (automatic Safari), AP6-4HW-1418 (Regal Safari) and AP6-4WHV-209 (V8 Safari). The difference in sheet metal is most notable where the rear bumpers on the later versions finish. On early build cars the rear bumper ends lead into a pressing on the lower rear quarter panel sheet metal, whereas on later build cars the bumper has curved ends with a flat sheet metal surface on the lower rear quarters.\nValiant V8 models were released in August 1965. A V8 sedan and V8 Safari wagon were offered, both powered by a V8 engine with “TorqueFlite 8” automatic transmission. V8 models could be identified by V8 badges, with the V8 sedan having a vinyl roof and the V8 Safari wagon being fitted with a roof rack. Power-assisted brakes were standard equipment. Although it utilized Regal trim and equipment, the V8 was marketed as the Valiant V8, not as a Valiant Regal V8.\nModel range.\nThe Valiant AP6 was offered in 4-door sedan, 5-door station wagon and 2-door coupé utility body styles in ten models.\nEngines and transmissions.\nA Straight-six engine was fitted to all models except the Valiant V8, which was powered by a V8 engine. Three speed manual and three speed automatic transmissions were offered.\nProduction and replacement.\nA total of 43,344 Valiant AP6s were produced prior to its replacement by the Valiant VC in 1966.", "Engineering,_Manufacturing": 0.9914266467, "qwen": "Yes"}
{"id": "43999623", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=43999623", "title": "Bottleneck (production)", "text": "In production and project management, a bottleneck is a process in a chain of processes, such that its limited capacity reduces the capacity of the whole chain. The result of having a bottleneck are stalls in production, supply overstock, pressure from customers, and low employee morale. There are both short and long-term bottlenecks. Short-term bottlenecks are temporary and are not normally a significant problem. An example of a short-term bottleneck would be a skilled employee taking a few days off. Long-term bottlenecks occur all the time and can cumulatively significantly slow down production. An example of a long-term bottleneck is when a machine is not efficient enough and as a result has a long queue.\nAn example is the lack of smelter and refinery supply which cause bottlenecks upstream.\nAnother example is in a surface-mount technology board assembly line with several pieces of equipment aligned. Usually the common sense strategy is to set up and shift the bottleneck element towards the end of the process, inducing the better and faster machines to always keep the printed circuit board (PCB) supply flowing up, never allowing the slower ones to fully stop; a strategy that could result in a deleterious (or damaging) and significant, overall drawback in the process.\nIdentifying bottlenecks.\nAlmost every system has a bottleneck, even if it is a minor one. If every system was running at full capacity, at least one machine would be accumulating processes. Identifying bottlenecks is critical for improving efficiency in the production line because it allows you to determine the area where accumulation occurs. The machine or process that accumulates the longest queue is usually a bottleneck, however this isn't always the case. Bottlenecks can be found through: identifying the areas where accumulation occurs, evaluating the throughput, assessing whether each machine is being used at full capacity, and finding the machine with the high wait time.\nAccumulation.\nWhen input comes in faster than the speed of the process, accumulation starts to occur. This means that the machine either does not have enough capacity, is not being fully utilized or has an under-qualified operator. This method is not effective at identifying bottlenecks where the queues are at several process steps, as there are multiple processes with accumulation.\nThroughput.\nSince the production line is directly linked to the output of the machines, it allows for the identifying of the main bottleneck in the manufacturing process. In changing each machines throughput, it will be possible to assess which machine affects the overall output the most, and hence determine the bottleneck in the chain of processes.\nFull capacity.\nBy using the utilization percentage of each production unit, it is possible to determine the machine which uses the highest percentage of its capacity. This machine is bottlenecking the other machines by 'forcing' them to operate at a lower capacity. However, if all machines in the chain of processes are running at a similar capacity level, increasing the capacity of the lowest machine will not create a significant improvement to the total output.\nWait times.\nIn the case where several production units are already running at full capacity, tracking the down time of machines will allow you to identify which machine is being bottlenecked. Usually the machine prior the machine with the highest wait or down time in the chain of processes is a bottleneck. The result of this is a machine being under utilized.\nFishbone diagram (Cause and Effect Diagram).\nA fishbone diagram is a graphical means for finding possible problems in a chain of processes. By collecting the different data related to the problem, and inputting them into the diagram, it becomes easier to analyze the data in the order it is used, and hence determine the root of the problem. This is commonly used to find the bottleneck in a chain of processes due to being able to pinpoint the machine precisely responsible for the delay in production.\nConsequences of bottlenecks in production.\nThe consequences of having bottlenecks in production are possible stalls in production, supply overstock, fall in employee morale, and loss of customers. Bottlenecks can result in the overloading of a machine. Overloading a machine can lead to the machinery getting damaged or worn out, and the result of this would be potential stretches of downtime in the long term.\nStall in production.\nA stall in production would be the result of one machine slowing down the entire chain of processes and consistently leaving the other machines unable to continue while it accumulates a large queue. This inefficiency significantly slows down production as many resources such as time, people, and machines are being paid to wait.\nSupply overstock.\nIn the event of accumulation in the long-term, the capacity at which the bottlenecked machine is running could be so slow that the accumulated resources that are in the queue need to be stored. The cost of storing resources is significant as it takes resources to transport the materials back and forth as well as requiring space, another potential cost.\nFall in employee morale.\nThe result of bottlenecks could require more work from employees as well as longer hours. In addition, there's the factor of stress and frustration with the bottlenecked machine and its operator. This could result in loss of efficiency as employees may not be very motivated to work.\nManaging bottlenecks.\nOnce the bottleneck has been identified, assessing the degree of the bottleneck is crucial for determining how to manage the bottleneck. The bottleneck could be either minor or severe. Minor bottlenecks may not need to be immediately addressed, whereas severe bottlenecks should be dealt with immediately. There are several ways to eliminate bottlenecks. Some means of doing so are: Adding resources to the bottleneck operation (more people), minimising downtime, eliminating non-value activities, investing in more machinery which completes the same action, and optimising the bottlenecks operation. Other sources similarly suggest that once the bottleneck has been identified it is best to ensure it is well maintained, to provide a constant buffer stock upstream of the bottleneck, to reduce time wasted in set ups and changeovers, and to train more operators for the bottlenecked machines. These are further explained below. Having production scheduled to optimise efficiency, is another means of effectively utilising the bottlenecked machine. This minimises the possibility that the production quota will not be met. Scheduling also reduces the number of situations where production is halted due to a lack of personnel, due to increased organisation and greater planned out production. It also allows for the full advantage of the time available to be taken, as pockets of time can be found to keep the machine running for as many hours as possible in a week.\nIncreasing number of operators or employees.\nIncreasing the number of operators or increasing the number of staff can be beneficial for multiple reasons. Increasing the number of operators can increase efficiency, as they can all work different timed shifts and hence the bottlenecked machine can run for longer hours. In addition, if one worker is sick, unable to work, or quits, there will always be someone available to replace him. Increasing the number of employees can be beneficial to increasing efficiency. This is because they can be reassigned to work on parts of the bottlenecked machines' operations which can be broken down into smaller activities and reassigned to reduce the work load of the machine, hence reducing the accumulation. Reassigning other work to different machines, allows less accumulation or delay for the bottlenecked machine. This significantly speeds up production, as it reduces the wait time of the machines farther along the chain of processes, increasing productivity.\nMinimizing downtime, setup and changeover time.\nTo compensate for being the weakest link in the chain of processes, the bottleneck machine will have to run for longer periods of time. Changeover and setup time should be minimised to allow the machines to run for slightly longer, reducing the impact of the bottleneck. Minimizing downtime by having the bottlenecked machines run from earlier until later is a common strategy for working around the problem, however this does increase the likelihood for the machine to be overloaded and need regular maintenance.\nEliminating non-value activities.\nIn removing all non-value activities, you reduce the amount of redundant tasks performed by the bottlenecked machine and hence maximize efficiency. Removing the waste operations results in a shorter cycle time hence allowing the machine to complete each process in less time.\nProvide a constant buffer stock upstream.\nIn order to optimise the usage of the machine, the machine should be kept running for as long as possible and hence should never have to wait for materials or stock, to increase productivity. This can be achieved by putting a buffer stock in place, so that the machine always has some task it can be doing. The down side to this strategy is that inventory space will be needed to store the buffer stock, for when the machine before it in the chain of processes, is working.\nPreventing bottlenecks.\nPreventing bottlenecks would be ideal to avoid having to manage and resolve them in the future. There are ways to work around them when planning the production environment. Giving employees free rein over minor decision making, will allow them to make the decision they feel is most efficient, and being operators of the machine, their experience will allow them to become specialised in the use of the machine over time. Cross-training employees will increase adaptability in the production line and therefore reduce potential downtime in the future. Hiring high performance employees will reduce the possibility for bottlenecks to be formed by underperforming employees who are inefficient at using their assigned machinery. Planning for a higher potential output when designing the production environment is crucial in the long run, for occurrences of larger orders when there is need to run all the machinery. Having all the machinery running at full capacity is not always ideal, due to situations where malfunctions occur and production is halted. Having inspiring leaders who have a strong understanding of how to keep production running smoothly, will allow greater control of all the different processes in the chain of production. Taking into account the layout of the different processes, can also increase efficiency as it minimises delay caused in the transportation stage. The use of a proper layout can reduce the overhead of machines and can reduce material handling time.\nEstablishment of standardized exchanged protocols, can minimise the potential for future bottlenecks to occur through minimising down time. This increases efficiency by reducing any potential confusion between different sectors and hence reduces the possibility for delays of the arrival of raw materials.\nStatic and dynamic systems and shifting bottlenecks.\nA static bottleneck is where no random or unexpected fluctuations (such as those that would happen during either a changeover or a breakdown of the system) occur. A static system does not change in behavior and hence the system stays constant. Finding a bottleneck in a static system is very simple, it is simply the machine or process with the longest constant cycle time. Static systems do not exist in reality as no matter what, there will always be a slight fluctuation in cycle time. This is because there is no way to prevent all fluctuations from occurring to slow the system down. An example of this could be a power shortage or a natural disaster. The behavior of any system is vulnerable to any random event and hence all systems are dynamic. Dynamic systems can be divided into two main groups: Stable and unstable. The significant difference in the context of dynamic systems, is that the bottlenecks can shift. The speed of which a bottleneck shifts depending on the buffer between the processes. Bottlenecks shift when the location of the work center in the production area changes, and this leads to control problems due to the significant delay in output. Shifting bottlenecks are a result of inevitable, unexpected events, for which no planning is possible.\nThe steps suggested to avoid or prevent shifting bottlenecks are:\nStep 1) Re-evaluate the maximum load of every machine, process or work center when accepting a new order.\nStep 2) Find the bottleneck in the system and identify its surplus capacity.\nStep 3) Fill the bottlenecks surplus capacity.\nStep 4) Find out the release time of the material as a result of the new bottlenecks scheduling.\nThrough following these steps, the order production will be completed in the shortest possible time frame.", "Engineering,_Manufacturing": 0.9997865558, "qwen": "Yes"}
{"id": "7599559", "revid": "44277652", "url": "https://en.wikipedia.org/wiki?curid=7599559", "title": "Gear manufacturing", "text": "Gear manufacturing refers to the making of gears. Gears can be manufactured by a variety of processes, including casting, forging, extrusion, powder metallurgy, and blanking. As a general rule, however, machining is applied to achieve the final dimensions, shape and surface finish in the gear. The initial operations that produce a semifinishing part ready for gear machining as referred to as blanking operations; the starting product in gear machining is called a gear blank.\nSelection of materials.\nThe gear material should have the following properties:\nGear manufacturing processes.\nThere are multiple ways in which gear blanks can be shaped through the cutting and finishing processes.\nGear forming.\nIn gear form cutting, the cutting edge of the cutting tool has a shape identical with the shape of the space between the gear teeth. Two machining operations, milling and broaching can be employed to form cut gear teeth.\nForm milling.\nIn form milling, the cutter called a form cutter travels axially along the length of the gear tooth at the appropriate depth to produce the gear tooth. After each tooth is cut, the cutter is withdrawn, the gear blank is rotated, and the cutter proceeds to cut another tooth. The process continues until all teeth are cut\nBroaching.\nBroaching can also be used to produce gear teeth and is particularly applicable to internal teeth. The process is rapid and produces fine surface finish with high dimensional accuracy. However, because broaches are expensive and a separate broach is required for each size of gear, this method is suitable mainly for high-quality production.\nGear generation.\nIn gear generation, the tooth flanks are obtained as an outline of the subsequent positions of the cutter, which resembles in shape the mating gear in the gear pair. There are two machining processes employed shaping and milling. There are several modifications of these processes for different cutting tool used.\nGear hobbing.\nGear hobbing is a machining process in which gear teeth are progressively generated by a series of cuts with a helical cutting tool. All motions in hobbing are rotary, and the hob and gear blank rotate continuously as in two gears meshing until all teeth are cut.\nFinishing operations.\nAs produced by any of the process described, the surface finish and dimensional accuracy may not \nbe accurate enough for certain applications. Several finishing operations are available, including the \nconventional process of shaving, and a number of abrasive operations, including grinding, honing, and lapping.", "Engineering,_Manufacturing": 1.0000029802, "qwen": "Yes"}
{"id": "26174708", "revid": "6561336", "url": "https://en.wikipedia.org/wiki?curid=26174708", "title": "Vibrating feeder", "text": "A vibratory feeder is an instrument that uses vibration to \"feed\" material to a process or machine. Vibratory feeders use both vibration and gravity to move material. Gravity is used to determine the direction, either down, or down and to a side, and then vibration is used to move the material. They are mainly used to transport a large number of smaller objects.\nA belt weigher are used only to measure the material flow rate but weigh feeder can measure the flow material and also control or regulate the flow rate by varying the belt conveyor speed.\nIndustries Served.\nVersatile and rugged vibratory bowl feeders have been extremely used for automatic feeding of small to large and differently shaped industrial parts. They are the oldest but still commonly used automation machine available for aligning and feeding machine parts, electronic parts, plastic parts, chemicals, metallic parts, glass vials, pharmaceuticals, foods, miscellaneous goods etc. \nAvailable in standard and custom designs, vibratory bowl feeders have been largely purchased by varied industrial sectors for automating high-speed production lines and assembly systems. Some of the industries that use the service of this automation machine include:\nWith these easy-to-use and high-performing part-feeding machines, customers from varied industrial sectors have achieved lower error rates, less power consumption, better profits, better rates of efficiency and less dependency on manpower.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "3498793", "revid": "9487993", "url": "https://en.wikipedia.org/wiki?curid=3498793", "title": "SL Corporation", "text": "SL Corporation (hangul:에스엘코포레이션) is a multinational automotive components manufacturing company headquartered in Gyeongsan, South Korea. It has manufacturing plants in Asia-Pacific, India, Europe, and the United States.\nAnnual turn-over is around 1.8billion USD\nas group basis.\nHistory.\nSL Corporation's origins date back to 1954 and the establishment of Samlip Motor Works as a manufacturer of bicycle parts. In 1968 the company was incorporated into Samlip Industrial Co. Ltd. (hangul:삼립산업) and in 1969 it began manufacturing head lamps for Hyundai Motors. The name was finally changed to SL Corporation in 2004 under the leadership of Lee Choong Kon, CEO. Currently SL Corporation manufactures various products for the automotive industry. SL Corporation received the GM Supplier of the Year award for sixteen straight years (1997–2012) as well as the Five Star quality certificate from Hyundai-Kia Motors.", "Engineering,_Manufacturing": 1.0000078678, "qwen": "Yes"}
{"id": "3504127", "revid": "43895768", "url": "https://en.wikipedia.org/wiki?curid=3504127", "title": "Boe-Bot", "text": "BOE–Bot is short for Board of Education robot. It is the trade name of a robot kit that is used in junior high, high school and college robotics classes. It consists of a main circuit board (the Board of Education) and breadboard, a plug–in BASIC Stamp microcontroller, two servo motors to drive the wheels, and an aluminum chassis that the parts bolt onto. Students can use Erector set parts, Lego blocks, and additional servos to build custom projects. The BOE-bot has been manufactured and sold by Parallax Inc since 1998.\nMain components.\nThe green detachable main circuit, mounted on the top of the robot is called the \"Board of Education\". The microcontroller which plugs into a socket on the green circuit board is called the BASIC Stamp . The BASIC Stamp is programmed in PBASIC. The rear wheel is a drilled polyethylene ball held in place with a cotter pin. Wheels are machined to fit on the servo spline and held in place with a screw. The BASIC Stamp is easy to program. The Boe–Bot is small, approximately four inches wide, and runs on four AA batteries. There is no soldering required for construction.\nFeatures.\nThe Boe–Bot is a robot that can be used in a variety of ways including combining Microsoft Robotics Developer Studio software with the Boe–Bot to control the robot's movements. The BOE–Bot is programmed using the PBASIC language.", "Engineering,_Manufacturing": 0.9999853373, "qwen": "Yes"}
{"id": "3505858", "revid": "28043514", "url": "https://en.wikipedia.org/wiki?curid=3505858", "title": "Electrogas welding", "text": "Electrogas welding (EGW) is a continuous vertical position arc welding process developed in 1961, in which an arc is struck between a consumable electrode and the workpiece. A shielding gas is sometimes used, but pressure is not applied. A major difference between EGW and its cousin electroslag welding is that the arc in EGW is not extinguished, instead remains struck throughout the welding process. It is used to make square-groove welds for butt and t-joints, especially in the shipbuilding industry and in the construction of storage tanks.\nOperation.\nIn EGW, the heat of the welding arc causes the electrode and workpieces to melt and flow into the cavity between the parts being welded. This molten metal solidifies from the bottom up, joining the parts being welded together. The weld area is protected from atmospheric contamination by a separate shielding gas, or by the gas produced by the disintegration of a flux-cored electrode wire. The electrode is guided into the weld area by either a consumable electrode guide tube, like the one used in electroslag welding, or a moving head. When the consumable guide tube is used, the weld pool is composed of molten metal coming from the parts being welded, the electrode, and the guide tube. The moving head variation uses an assembly of an electrode guide tube which travels upwards as the weld is laid, keeping it from melting.\nElectrogas welding can be applied to most steels, including low and medium carbon steels, low alloy high strength steels, and some stainless steels. Quenched and tempered steels may also be welded by the process, provided that the proper amount of heat is applied. Welds must be vertical, varying to either side by a maximum of 15 degrees. In general, the workpiece must be at least 10 mm (0.4 in) thick, while the maximum thickness for one electrode is approximately 20 mm (0.8 in). Additional electrodes make it possible to weld thicker workpieces. The height of the weld is limited only by the mechanism used to lift the welding head—in general, it ranges from 100 mm (4 in) to 20 m (50 ft).\nLike other arc welding processes, EGW requires that the operator wear a welding helmet and proper attire to prevent exposure to molten metal and the bright welding arc. Compared to other processes, a large amount of molten metal is present during welding, and this poses an additional safety and fire hazard. Since the process is often performed at great heights, the work and equipment must be properly secured, and the operator should wear a safety harness to prevent injury in the event of a fall.\nEquipment.\nEGW uses a constant voltage, direct current welding power supply, and the electrode has positive polarity. The welding current can range from 100 to 800 A, and the voltage can range between 30 and 50 V. A wire feeder is used to supply the electrode, which is selected based on the material being welded. The electrode can be flux-cored to provide the weld with protection from atmospheric contamination, or a shielding gas—generally carbon dioxide—can be used with a solid wire electrode. The welding head is attached to an apparatus that elevates during the welding process. Also attached to the apparatus are backing shoes which restrain the weld to the width of the workpieces. To prevent them from melting, they are made of copper and are water-cooled. They must be fit tightly against the joint to prevent leaks.", "Engineering,_Manufacturing": 0.999990344, "qwen": "Yes"}
{"id": "3511605", "revid": "22411294", "url": "https://en.wikipedia.org/wiki?curid=3511605", "title": "Blister pack", "text": "A blister pack is any of several types of pre-formed plastic packaging used for small consumer goods, foods, and for pharmaceuticals.\nThe primary component of a blister pack is a cavity or pocket made from a formable web, usually a thermoformed plastic. This usually has a backing of paperboard or a lidding seal of aluminum foil or plastic. A blister that folds onto itself is often called a clamshell.\nBlister packs are useful for protecting products against external factors, such as humidity and contamination for extended periods of time. Opaque blisters also protect light-sensitive products against UV rays.\nUses.\nBlister packs are used to package products such as toys, hardware, medication, etc. Many blister packaging machines use heat and pressure via a die to form the cavity or pocket from a roll or sheet of plastic. In recent years, improvements in cold forming—specifically allowing steeper depth/angles during forming, which minimizes the amount of material used for each cavity—have helped this technology increase. The main advantages of the plastic-based blister pack are its more compact size compared to cold formed aluminum and its transparency to see the product.\nUnit dose packaging of pharmaceuticals.\nBlister packs are commonly used as unit-dose packaging for pharmaceutical tablets, capsules or lozenges. Blister packs can provide barrier protection for shelf life requirements, and a degree of tamper resistance. In the US, blister packs are mainly used for packing physician samples of drug products or for over-the-counter (OTC) products in the pharmacy. In other parts of the world, blister packs are the main packaging type since pharmacy dispensing and re-packaging are not common. A series of blister cavities is sometimes called a blister card or blister strip as well as blister pack. The difference between a strip pack and blister pack is that a strip pack does not have thermo-formed or cold formed cavities; the strip pack is formed around the tablet at a time when it is dropped to the sealing area between sealing moulds. In some parts of the world the pharmaceutical blister pack is known as a push-through pack (PTP), an accurate description of two key properties (i) the lidding foil is brittle, making it possible to press the product out while breaking the lidding foil and (ii) a semi-rigid formed cavity being sufficiently collapsible to be able to dispense the tablet or capsule by means of pressing it out with the thumb. Breaking the lidding foil with a fingernail for the appropriate tablet will make the pressing out easier.\nThe main advantages of unit-dose blister packs over other methods of packing pharmaceutical products are the assurance of product/packaging integrity (including shelf-life) of each individual dose and the ability to create a compliance pack or calendar pack by printing the days of the week above each dose.\nBlister packs are created by means of a form-fill-seal process at the pharmaceutical company or designated contract packer. A form-fill-seal process means that the blister pack is created from rolls of flat sheet or film, filled with the pharmaceutical product and closed (sealed) on the same equipment. Such equipment is called a blisterline. There are two types of blister machine' design: rotary and flat-plate, depending on the mechanism for sealing the lidding foil.\nConsumer goods.\nOther types of blister packs consist of carded packaging where goods such as toys, hardware, and electrical items are contained between a specially made paperboard card and clear pre-formed plastic such as PVC. The consumer can visually examine the product through the transparent plastic. The plastic shell is vacuum-formed around a mold so it can contain the item snugly. The card is colored and designed depending on the item inside, and the PVC is affixed to the card using heat and pressure to activate an adhesive (heat seal coating) on the blister card. The adhesive is strong enough so that the pack may hang on a peg, but weak enough so that the package can be easily opened (in theory). Sometimes, with large items, the card (cold seal card) has a perforated window for access.\nClamshell.\nA hinged blister is known as a clamshell, used for a variety of products. It can be used as a security package to deter package pilferage for small high-value items, such as consumer electronics. It consists of one sheet folded over onto itself and sometimes fused at the edges. They can be securely heat sealed, making them difficult to open by hand to deter tampering. A pair of scissors or a sharp knife is often required to open them (although these are often sold in similar packages). Trauma shears are also effective at opening packaging of this type. Care must be used to safely open some of these packages, as opening it without care can result in injury; 6,000 Americans are sent to the emergency room each year by injuries suffered in opening such packages.\nWrap rage is sometimes the result.\nMedical blister trays.\nMedical blister trays differ from pharmaceutical blister packs in that these are not push-through packs. The thermoformed base web is made of a thicker plastic sheet, generally between 500 and 1000 µg and can not be collapsed, thus forming a solid tray. The lidding film provides a peel-open feature and is generally porous to allow sterilization (such as the Dupont medical Tyvek material). Such medical blister packs are used for sterile medical devices, used in hospitals.\nMethods.\nThermoforming.\nIn the case of thermoforming, a plastic film or sheet is unwound from the reel and guided though a pre-heating station on the blister line which will cause the plastic to soften and become pliable. The warm plastic will then arrive in a forming station where a large pressure (4 to 8 bar) will form the blister cavity into a negative mold. The mold is cooled such that the plastic becomes rigid again and maintains its shape when removed from the mold. In case of difficult shapes, the warm film will be physically pushed down partially into the cavity by a \"plug-assist\" feature. Plug-assist results in a blister cavity with more uniform wall distribution and is typically used when the cavity size and shape is larger than a small tablets and cables.\nCold forming.\nIn the case of cold forming, an aluminum-based laminate film is simply pressed into a mold by means of a stamp. The aluminum will be elongated and maintain the formed shape. In the industry these blisters are called cold form foil (CFF) blisters. The principal advantage of cold form foil blisters is that the use of aluminum offers a near complete barrier for water and oxygen, allowing an extended product expiry date. The principal disadvantages of cold form foil blisters are: the slower speed of production compared to thermoforming; the lack of transparency of the package (a therapy compliance disadvantage); and the larger size of the blister card (aluminum can not be formed with near 90-degree angles).\nThermo cold forming.\nIn thermo cold forming process, the first packing is done by thermoforming technique after which the product is repacked with a cold forming package.\nMaterials.\nPVC.\nThe most basic material for the forming web is polyvinyl chloride (PVC). The principal advantages of PVC are the low cost and the ease of thermoforming. The main disadvantages are the poor barrier against moisture ingress and oxygen ingress. In the case of blister packaging the PVC sheet does not contain any plasticizer and is sometimes referred to as Rigid PVC or RPVC. In the absence of plasticizers, PVC blisters offer structural rigidity and physical protection for the pharmaceutical dosage form. On the other hand, the blister cavity must remain accessible by the push-through effect and the formed web may not be too hard to collapse when pressed upon; for this reason the PVC sheet thickness is typically chosen between 200µ to 300µ depending on the cavity size and shape. Most PVC sheets for pharmaceutical blisters are 250µ or 0.250 mm in thickness. Typical values for the Water Vapor Transmission Rate (WVTR or MVTR) of a 250µ PVC film are around 3.0 g/m2/day measured at 38 °C/90% RH and the Oxygen Transmission Rate (OTR) is around 20 mL/m2/day. In order to overcome the lack of barrier properties of PVC film, it can be coated with PVDC or laminated to PCTFE or COC to increase the protective properties. Multi-layer blister films based on PVC are often used for pharmaceutical blister packaging, whereby the PVC serves as the thermoformable backbone of the structure. Also, the PVC layer can be colored with pigments and/or UV filters. The European Pharmacopoeia (Ph Eur) references the requirements for PVC blister packs for pharmaceutical primary packaging in the monograph EP 3.1.11 \"MATERIALS BASED ON NON-PLASTICISED POLY(VINYL CHLORIDE) FOR CONTAINERS FOR DRY DOSAGE FORMS FOR ORAL ADMINISTRATION\". In order to be suitable for pharmaceutical blister packs, the PVC formulation also needs to comply with the US Pharmacopoeia ; EU food legislation; US 21.CFR and Japanese food contact requirements.\nPVDC.\nPolyvinylidene chloride (PVDC) can be coated onto a PVC film to obtain very high moisture and oxygen barrier properties depending on the coating weight. PVDC coated blister films are the most common and prevailing barrier films used for pharmaceutical blister packs. PVDC coatings are also the most economical method for adding water barrier and oxygen barrier properties to a PVC film. PVDC blister films are available in 2 or 3 layer specifications referred to as duplex or triplex. Since the PVDC is applied by a coating process, the coating weight is expressed in grams per square meter (gsm). Duplex structures are typically PVC/PVDC films, ranging from 250µPVC/40gsmPVDC to 250µPVC/120gsmPVDC with WVTR from 0,65 to 0,25 g/m2/d and OTR from 1 to 0,1 cc/m2/d. For very deep draw thermoformed cavities, the triplex specifications are used : PVC/PE/PVDC, where the PE layer assists when forming deeper cavities. The PE (polyethylene) forms a soft intermediate layer between the rigid PVC and PVDC layers. Triplex specifications exists in similar coating weights as duplex specifications: 250µPVC/25µPE/40gsmPVDC up to 250µPVC/25µPE/120gsmPVDC.\nIn order to obtain high barrier properties, PVDC is always applied using an emulsion coating process using a PVDC resin dispersed in water. The film producer applies the coating in several steps, drying-off the water between each coating station.\nPVDC grades are available in 2 types of polymer: (I) the historic grades offering medium to high barrier properties and (II) a super barrier coating grade offering the highest barrier. The SBC grade has over two times the barrier to moisture and oxygen per gram coating weight compared to the historic grades. The most common structures using the super barrier PVDC are triplex configurations 250µ PVC/25µ PE/120gsm PVDC up to 250µ PVC/25µ PE/180gsm PVDC, with WVTR of 0,11 down to 0,06 g/m2/day and available from various suppliers.\nPCTFE.\nPolychlorotrifluoroethylene (PCTFE) can be laminated to PVC to obtain very high moisture barrier. Typical constructions used for pharmaceutical products are 250µ PVC film laminated to 15µ-150µ PCTFE film. Duplex structures are PVC/PCTFE and triplex laminates are PVC/PE/PCTFE. Deeper cavities can be formed by using the triplex structures with PE. Typical WVTR values are 0.06–0.40 g/m2/day. PCTFE films have the lowest water vapor permeation compared to all other plastic films used in blister packaging and have thermoforming properties similar to plain PVC though it is also the most expensive. Despite narrow thermoforming temperatures and required cooling steps PP is increasingly popular. This popularity is due in part to it not suffering the environmental liability that PVC suffers in discharging hydrochloric acid during incineration. Unplasticised PVC has good thermoforming properties but may not provide good moisture protection for some products. After the forming process a 250 µm film will have a final thickness of 50 to 100 µm in some deep drawn pockets. The reduction in thickness will result in an increase in WVT.\nCOC.\nCyclic olefin copolymers (COC) or polymers (COP) can provide moisture barrier to blister packs, typically in multilayered combinations with polypropylene (PP), polyethylene (PE), or glycol-modified polyethylene terephthalate (PETg). Cyclic olefin resins are generally amorphous and are noted for good thermoforming characteristics even in deep cavities, leading some to use COC in blister packaging as a thermoforming enhancer, particularly in combination with semicrystalline resins such as PP or PE. Films can be manufactured via coextrusion or lamination. WVTR values of commercial cyclic olefin-based pharmaceutical blister films typically range from 0.20 to 0.35 g/m2/day at 38 °C/90% RH. Unlike PVC and other common pharmaceutical barrier resins, cyclic olefin resins do not contain chlorine or other halogens in their molecular structure, being composed solely of carbon and hydrogen. Cyclic olefin resins are available which comply with pharmaceutical packaging guidelines in the US, Europe, and Japan.\nCold form foil.\nCold form foil film (or cold-formed foil) is made of a 3-layer laminate: PVC/Aluminum/Polyamide. The PVC side is on the inside in contact with the product. \nLidding foils.\nPharmaceutical blister packs are mostly closed by a push-through or peel-open lidding foil. The most common lidding foil with push-through features is 20µ hard tamper aluminum, which can be supplied pinhole-free from the producers. The lidding foil is coated with a heat-seal lacquer on the inside and a print primer on the outside.\nBenefits.\nCost savings.\nBlister packaging is a cost-effective way of showcasing a product. Due to the nature of the material and design, it makes it more cost-effective than other types of packages that are on the market. There are several different types of blister packaging – Face Seal, Trap, Mock, Slide and Interactive. Each one has its unique qualities and price points, from entry level to high end.\nAdvertising space.\nThere is a wide range of colors and finishes that blister packaging can be constructed to feature. Manufacturers can use that to help make their products stand out on shelves. Blister packaging allows either the manufacturer or retailer to include promotional materials or advertisements to help build a brand and increase customer loyalty.\nClear product display.\nBlister packaging helps shoppers see product, further aiding in their purchase decision. More than half of shoppers believe it is important to see a product through its packaging.\nTheft deterrent packaging.\nTo prevent retail theft, packages are specifically designed so that the customer cannot \"touch and feel\" the product. Clear, protective, and durable thermoformed plastic packaging enables the customer to fully view the product while maintaining the security of the product. Blister packaging can easily be sealed using heat sealing machinery.\nTamper evident.\nA tamper-evident package, according to the regulations of the Food and Drug Administration (21 CFR § 211.132), \"is one having one or more indicators or barriers to entry which, if breached or missing, can reasonably be expected to provide visible evidence to consumers that tampering has occurred\". In addition, the indicator or barrier must be \"distinctive by design\", which means the tamper-evident feature is designed from material not readily available to the public. Therefore, it cannot be easily duplicated. The labeling must also include a description of the safety feature. For blister packaging, each tablet or capsule is individually sealed, so any form of tampering is immediately visible. The product label needs to include a statement similar to the following: \"Do not use if blister is cut or broken\".\nSuicide prevention.\nMedication placed in blister packs has reduced intentional overdoses.", "Engineering,_Manufacturing": 0.9997496009, "qwen": "Yes"}
{"id": "3707827", "revid": "44012373", "url": "https://en.wikipedia.org/wiki?curid=3707827", "title": "Manettino dial", "text": "In automotive engineering, a manettino dial is a rotary switch part of some modern Ferrari cars first designed by Frank Stephenson, beginning with the Ferrari F430 in 2004. The adjustment dial is mounted on the steering wheel, usually just underneath the center of the wheel. The dial  is inspired by the controls found on , but have a more polished appearance.\nThe dial allows for the quick and simple adjustment of the electronics governing car suspension settings, traction control, electronic differential, and change speed of electronic gearbox.\nA similar control system was employed on the Ferrari Enzo, but used individual buttons for different settings rather than a single rotary switch.", "Engineering,_Manufacturing": 0.9966665506, "qwen": "Yes"}
{"id": "3715184", "revid": "1165483910", "url": "https://en.wikipedia.org/wiki?curid=3715184", "title": "Firescale", "text": "Firestain is a layer of oxides that is visible on the surface of objects made of metal alloys containing copper when the object is heated, as by a jeweler heating a ring to apply solder during a repair. On copper-containing alloys of gold or of silver (such as sterling silver), it presents as a red or purple stain. This is because at high temperatures, oxygen mixes with the copper to form cuprous oxide and then cupric oxide, both of which disrupt the bright polished surface of the finished piece.\nAttempts to reduce the problem of firestain include preventative and curative ones. Firestain can be largely prevented by heating the object in an atmosphere in which the oxygen has been replaced with another combustive gas such as hydrogen or ammonia.\nOn the curative side, firestain can sometimes be removed by polishing, sanding, grinding, filing, wire brushing, and the like. As the layer firestain is often not very deep, this approach, with sufficient effort and time, may be able to remove it. However, this inevitably results in a loss of material to the piece, and will cause any fine details to the piece to be lost. However, it does not involve the use of any special gasses or changes to the heating atmosphere around the piece.\nAs another cure, objects can also be \"bombed\" or electrostripped. This involves placing them in a bath of a usually cyanide-based solution (sometimes nitric acid may be used instead, as well as other solutions) and applying a high-density electric current arranged so that the work piece functions as an anode. Other approaches include electroplating the object with a layer of the principal metal of the alloy, as well as, for sterling and similar grades of silver, depletion silvering the piece, and for gold-copper alloys, a sodium dichromate pickle solution with a low percentage of sulfuric acid has been occasionally found effective. These approaches, however, are temporary fixes in that all they do is cover up the firestain: over time, it will almost always reemerge through the thin layer of overlying metal deposit. The only long-term techniques to prevent the appearance of firestain are through its time-consuming physical removal or preventing its formation in the first place, by using an oxygen-free environment (which is often expensive and requires specialized equipment), or by using an alloy which is resistant to firestain such as argentium.", "Engineering,_Manufacturing": 0.9984737635, "qwen": "Yes"}
{"id": "7003716", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=7003716", "title": "Diamond tool", "text": "A diamond tool is a cutting tool with diamond grains fixed on the functional parts of the tool via a bonding material or another method. As diamond is a superhard material, diamond tools have many advantages as compared with tools made with common abrasives such as corundum and silicon carbide.\nHistory.\nIn \"Natural History\", Pliny wrote \"When an \"adamas\" is successfully broken it disintegrates into splinters so small as to be scarcely visible. These are much sought after by engravers of gems and are inserted by them into iron tools because they make hollows in the hardest materials without difficulty.\"\nAdvantages.\nDiamond is one of the hardest natural materials on earth; much harder than corundum and silicon carbide. Diamond also has high strength, good wear resistance, and a low friction coefficient. So when used as an abrasive, it has many obvious advantages over many other common abrasives.\nAdvantages of diamond grinding tools.\nDiamond can be used to make grinding tools, which have the following advantages:\nCategories.\nThere are thousands of kinds of diamond tools. They can be categorized by their manufacturing methods and their uses.\nCategories by manufacturing method.\nAccording to their manufacturing methods or bond types, diamond tools can be categorized to the following way:\nCategories by use.\nIf categorized by use, there are diamond grinding tools, diamond cutting tools (e.g., diamond coated twist drill bits), diamond drilling tools, diamond sawing tools (e.g., diamond saw blades), diamond drawing dies, etc.\nApplications.\nApplicable materials.\nDiamond tools are suitable to process the following materials:\nAs diamonds can react with Fe, Co, Ni, Cr, V under the high temperatures generated in the grinding processes, normally diamond tools are not suitable to process steels, including common steels and various tough alloy steels, while the other superhard tool, cubic boron nitride (CBN) tool, is suitable to process steels. The tools made with common abrasives (e.g. corundum and silicon carbide) can also do the task.\nApplied domains.\nDiamond tools are used in the following domains:\nBesides what are listed above, there are also other domains where diamond tools are applied, for example, in medicine, Venezuelan scientist Humberto Fernandez Moran invented the diamond knife for use in delicate surgeries in 1955.\nApart from its use as an abrasive due to its high hardness, diamond is also used to make other products for its many other good properties such as high heat-conductivity, low friction coefficient, high chemical stability, high resistivity and high optical performances. These applications include coatings on bearings and CDs, acting as lens and thermistors, making high-voltage switches and sensors, etc.\nSome examples of diamond tools.\nDiamond dressing tools.\nDiamond dressers consist of single-point or multipoint tools brazed to a steel shank, and used for the trueing and dressing of grinding wheels. The tools come in several types, including: grit impregnated, blade type, crown type, and disc type. The advantages of multipoint over single-point tools are:\nPCD cutting tools.\nPolycrystalline diamond (PCD) is formed in a large High Temperature-High Pressure (HT-HP) press, as either a diamond wafer on a backing of carbide, or forming a \"vein\" of diamond within a carbide wafer or rod.\nMost wafers are polished to a mirror finish, then cut with an electrical discharge machining (EDM) tool into smaller, workable segments that are then brazed onto the sawblade, reamer, drill, or other tool. Often they are EDM machined and/or ground an additional time to expose the vein of diamond along the cutting edge. These tools are mostly used for the machining of nonmetallic and nonferrous materials.\nThe grinding operation is combined with EDM for several reasons. For example, according to Modern Machine Shop, the combination allows a higher material removal rate and is therefore more cost effective. Also, the EDM process slightly affects the surface finish. Grinding is used on the affected area to provide a finer final surface. The Beijing Institute of Electro-Machining attributes a finer shaping and surface geometry to the combination of the two processes into one.\nThe process itself is accomplished by combining the two elements from each individual process into one grinding wheel. The diamond graphite wheel accomplishes the task of grinding, while the graphite ring around the existing wheel serves as the EDM portion. However, since diamond is not a conductive material, the bonding in the PCD work piece must be ample enough to provide the conductivity necessary for the EDG process to work.\nPolycrystalline diamond tools are used extensively in automotive and aerospace industries. They are ideal for speed machining (9000 surface feet per minute or higher) in tough and abrasive aluminum alloys, and high-abrasion processes such as carbon-fiber drilling and ceramics. The diamond cutting edges make them last for extended periods before replacement is needed. High volume processes, tight tolerances, and highly abrasive processes are ideal for diamond tooling.\nPolycrystalline diamond compacts.\nIn the late 1970s, General Electric pioneered the technology of polycrystalline diamond compacts (PDCs) as a replacement for natural diamonds in drill bits. PDCs have been used to cut through crystalline rock surfaces for extended periods of time in lab environments, and these capabilities have now been implemented in harsh environments throughout the world.\nAs of August 2000, the U.S. Department of Energy claimed that nearly one-third of the total footage drilled worldwide is being drilled with PDC bits, with a claimed savings of nearly $100,000 per PDC bit as compared to roller-core bits.\nDiamond paste and slurry.\nDiamond pastes are used for polishing materials that require a mirror finish. They are often used in metallurgical specimens, carbide dies, carbide seals, spectacle glass industry, and for polishing diamonds. Diamond paste is mainly used in industrial requirements for polishing and sharpening metal blades and other metal surfaces. The paste is not just to polish the metal blade but sharpen the cutting edge as well.\nDiamond electroplated tools.\nDiamond powder deposited through electroplating is used to make files (including nail files) and in small grinding applications.\nSingle point diamond turning tools.\nSingle point diamond turning (SPDT) utilizes a solid, flawless diamond as the cutting edge. The single crystalline diamond can be natural or synthetic, and is sharpened to the desired dimensions by mechanical grinding and polishing. The cutting edge of most diamond tools is sharp to tens of nanometers, making it very effective for cutting non-ferrous materials with high resolution. SPDT is a very accurate machining process, used to create finished aspherical and irregular optics without the need for further polishing after completion. The most accurate machine tool in the world, the LODTM, formerly at Lawrence Livermore National Laboratory, had a profile accuracy estimated at 28 nm, while most machines seek a roughness within that deviation.\nSPDT is used for optics, for flat surfaces where both surface finish and unusually high dimensional accuracy are required, and when lapping would be uneconomical or impractical.\nDiamond saw blades.\nFor high-speed gas powered cut-off saws, walk-behind saws, handheld grinders, bridge saws, table saws, tile saws, and other types of saws.\nDiamond tipped grinding cups.\nTypically used on hand grinders for grinding concrete or stone.\nDiamond tipped core bit or holesaw.\nHollow steel tube with diamond tipped segments for drilling holes through concrete walls in the construction industry, porcelain tiles or granite worktops in the domestic industry, or also used for sample core extractions in the mining industry.\nPCD tool insert.\nUsed in machine tools for machining ceramics and high speed aluminium.\nPD tool insert.\nUsed in turning centers for optics and precision surfaces.\nPolishing pads.\nPads with diamond crystals for polishing marble and other fine stone.\nDiamond wire cutting.\nWire with diamond crystals for cutting.\nSome of the features of Diamond Wire Cutting are:\nNon-percussive, fumeless and quiet\nSmooth cutting face\nUnlimited cutting depth\nHorizontal, vertical and angled cutting of circular openings up to 2500mm diameter\nPlunge cutting facility which allows blind and rebated openings to be formed\nRemote controlled operation for increased safety\nDiamond saw chain.\nFor cutting stone, concrete and brick with a special chainsaw.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "17586960", "revid": "19090830", "url": "https://en.wikipedia.org/wiki?curid=17586960", "title": "Bar stock", "text": "Bar stock, also (colloquially) known as blank, slug or billet, is a common form of raw purified metal, used by industry to manufacture metal parts and products. Bar stock is available in a variety of extrusion shapes and lengths. The most common shapes are round (circular cross-section), rectangular, square and hexagonal. A bar is characterised by an \"enclosed invariant convex cross-section\", meaning that pipes, angle stock and objects with varying diameter are not considered bar stock.\nBar stock is commonly processed by a sequence of sawing, turning, milling, drilling and grinding to produce a final product, often vastly different from the original stock. In some cases, the process is partially automated by specialized equipment which feeds the stock into the appropriate processing machine.\nProcess and types.\nMost metal produced by a steel mill or aluminium plant is formed (via rolling or extrusion) into long continuous strips of various size and shape. These strips are cut at regular intervals and allowed to cool, each segment becoming a piece of bar stock. A good analogy is pasta-making, in which lumps of dough are extruded into various cross-sectional shapes; cut into lengths; and then dried in that form. The cross-sectional shapes of pasta vary from simple bar or tube shapes (such as linguine or penne) to more elaborate extrusions (such as rotelle, fiori, or rotini). The same is true of metal bar stock. The most common shapes are round bar (also called rod), rectangular bar (including square bar, the special case of equal sides), and hexagonal bar (usually called hex bar for short). Tube and pipe are similar, but have hollow centers and are traditionally not called \"bar\" in industrial usage. (However, a product called hollow bar, essentially tube but with custom-orderable OD and ID and thus custom wall thickness, is marketed for lathe bar work which can benefit from obviation of drilling and rough boring.) Also similar in concept, but not called \"bar\", are the common structural shapes such as angle stock and channel stock. These are commonly available in steel and aluminum; the names \"angle iron\" and \"channel iron\" are still commonly used (informally) even though their literal namesake, wrought iron, has been replaced by steel and aluminum for most uses.\nIn a machine shop, bar stock and plate are often called \"billet\", although in a rolling mill, that word refers to a piece of metal that has not yet been rolled into bar.\nA machine shop typically has a storage area containing a large variety of bar stock. To create a metal component, a bar of sufficient volume is selected from storage and brought to the machining area. This piece may then be sawed, milled, drilled, turned, or ground to remove material and create the final shape. In turning, for large-diameter work (typically more than , although there is no universal threshold), a piece of the bar is cut off using a horizontal bandsaw to create a \"blank\" for each part. The blanks are then fed into a chucking lathe (chucker) which chucks each one in turn. For smaller-diameter work, the entire length of bar stock is more often fed through the spindle of the lathe. The entire bar rotates with the spindle during the part-machining cycle. When the cycle ends and one part is done, the chuck opens, the bar is pulled or pushed forward (\"fed\") by any of various automatic means, the chuck closes, and the next cycle begins. The last step of the cycle is to cut off the machined part from the bar, which is called \"parting it off\" and is achieved with a \"cutoff\" or \"part-off\" tool, a tool bit that grooves the bar all the way down to the centreline, causing the part to fall off. Then the cycle repeats.\nThe not-yet-cut bar protruding from the back of the spindle, rotating quickly, can present a safety hazard if it is sticking out too far and unconstrained from bending. Thus sometimes long bars must be sawn into shorter bars before being fed as \"bar work\" (which is the term for such work).\nCNC lathes and screw machines have accessories called \"bar feeders\", which hold, guide, and feed the bar as commanded by the CNC control. More advanced machines may have a \"bar loader\" which holds multiple bars and feeds them one at a time into the bar feeder. Bar loaders are like magazines for part blanks (or pallets for milling work) in that they allow lights-out machining. The bar loader is filled with bars (or the magazine or pallet with part blanks) during working hours, and then it runs during the night unattended. Given that there is no human around to detect if something went wrong and the machine should stop, there are various kinds of sensors that are used to detect this, such as load meters, infrared beams, and, in recent years, webcams, which are placed inside the machine tool's enclosure and allow remote viewing of the cutting action.\nUses of bar stock.\nBar stock is widely used in many industries and can be seen in many different industrial processes. These processes include forging, extrusion, machining, and many more. In forging, billets are heated to high temperatures before a press pushes the workpiece into the shape on the die. These presses operate at very high forces to make the desired changes to the product. Extrusion uses rollers that push the heated bar stock through a set of dies which will determine the shape of the workpiece. Machining is a subtractive process that utilizes bar stock and various cutters and tools to make intricate details that are not possible through other processes.\nStandard sizes throughout a supply chain.\nTo stock every possible size of bar stock (every possible fraction of a millimeter or inch in diameter or thickness) is impossible. Thus, bar stock is stocked by metals supply houses in various standard sizes, arrayed in discrete steps. For example, round bar with diameters of even millimeters (or in the US, on the eighths of an inch) can usually be ordered from standing stock. Bar diameters of nonstandard sizes can also be obtained, but only as a separate mill run from the rolling mill. Thus they are much more expensive than the standard sizes, can take much longer delivery time, and are not desirable as inventory for the supply house or the machine shop (because the chance of selling or using any particular custom size is slim).\nSometimes it is necessary that the bar not be very much larger than the intended part, because the metallurgical properties of some metal alloys in some finishing processes may vary by how far inside the bar the metal lies. Thus an engineering drawing will specify a certain size (or a maximum size) that the bar may start out as. These specs face the aforementioned limitation of stocking sizes versus custom mill runs; standard sizes are used wherever possible to avoid wasted expense and needless delays.\nDrill rod.\nA drill rod is tool steel round stock ground to a tight tolerance diameter; it is usually ± . In the UK the name \"silver steel\" is often synonymous and sometimes hyponymous. Its origin was in reference to the shiny ground appearance (not to any silver alloying content). Drill rod diameters range from ; in the United States diameters smaller than th of an inch  are made in letter drill sizes and number drill sizes, in addition to fractional sizes. Lengths are usually . It is commonly used to make drill bits, taps, reamers, punches, dowel pins, and shafts. Note that the numbered sizes are different from the drill numbered sizes starting at 52. These sizes are:\nDrill blanks have an undersize tolerance of +0/−, while reamer blanks have an oversize tolerance of −0/+0.\nSome mills also sell square stock that is held to the same tolerances under the name \"drill rod\".\nCommonly available material grades in the U.S. are A2, D2, M2, M42, O1, S7, W1, and high speed steel (including M2/M7).\nGround flat stock.\n\"Ground flat stock\" is annealed steel that has been ground to close tolerances (compare to drill rod). There are four types of materials available: O-1 tool steel, A-2 tool steel, A-6 tool steel, and 1018 steel (low-carbon or low-carb steel). Lengths are either long, various widths up to are available, and thicknesses range from .\nSome geometrical sizes are known as \"\".\nReferences.\n ", "Engineering,_Manufacturing": 0.9998912811, "qwen": "Yes"}
{"id": "24482634", "revid": "38448542", "url": "https://en.wikipedia.org/wiki?curid=24482634", "title": "MazaCAM", "text": "MazaCAM is a CNC programming system for the Mazak CNC (Numerical control) machine-tools (see Yamazaki Mazak Corporation), sold and supported by SolutionWare Corporation.\nMazaCAM differs from most other CNC programming systems in that it can generate CNC programs in both Mazatrol and G-code .\nReferences.\nOther Sources of Notability\n\n\n\n\n", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "12867268", "revid": "44526759", "url": "https://en.wikipedia.org/wiki?curid=12867268", "title": "Sirris", "text": "Sirris is a non-profit scientific organisation in Belgium. It is an important collaborative centre for the Belgian technology industry. Until 2007, Sirris was known as \"CRIF-WTCM\", which was founded in 1949 by Fabrimetal (now known as Agoria, the Belgian federation of technology industries).\nMission.\nThe mission of Sirris is to support its members and clients in order to increase their competitive position on the international market through technological innovation. The organization carries out applied research and development in close cooperation with industry. Sirris participates in development projects at different levels, from European Framework Programmes for Research and Technological Development to regional ones.\nCOPTURN.\nOne of the biggest achievements of Sirris so far is the Cutting Optimisation Program, or COPTURN for short. It is a software package that is used to calculate the optimal cutting conditions, the program then calculates the job time and cost.\nDevelopment fields.\nAdditive manufacturing.\nSirris performs researches on mains additive manufacturing technologies such as selective laser melting, 3D printing, laser cladding, stereolithography, selective laser sintering, Aero Jet Printing and paste polymerization (ceramic + polymer).\nAll these technologies start from a CAD file to build it in metal, polymer or ceramic. In November 2019, Sirris inaugurates an additive production line demonstrator combining design and production processes by additive manufacturing and principles and processes 4.0.\nProduct Development Hub.\nIn 2018, Sirris invested 850,000 euros in a new infrastructure focused on three areas: light products, miniaturisation and product connectivity in order to enable companies to enable prototyping quickly for industrialization.", "Engineering,_Manufacturing": 0.997400105, "qwen": "Yes"}
{"id": "12881338", "revid": "10837", "url": "https://en.wikipedia.org/wiki?curid=12881338", "title": "Porosity sealing", "text": "Porosity sealing is done through the process of vacuum impregnation. Vacuum impregnation is a preferred OEM process that seals porosity and leak paths in metal castings, sintered metal parts and electrical castings that form during the casting or molding process. Vacuum impregnation stops casting porosity (a phenomenon that occurs in the die-cast manufacturing process and allows manufacturers to use parts that would otherwise be scrapped.) \nPorosity occurs naturally and is found in most materials. In metal castings, porosity is typically considered any void found in the casting. Casting porosity can be caused by gas formation or solidification while the metal is being moved from a liquid state to a solid state. This porosity can range in size, from sub-micron to voids greater than 10 mm, depending on the casting.\nCasting defects caused by porosity can affect the part’s structural integrity, creating a failure point. Porosity can also prevent the part from being pressure tight. This will impact performance if the part is designed to hold gases or fluids.\nProcess Standards.\nVacuum impregnation is governed by Military Standard MIL-I-17563C and MIL-STD-276A as well as numerous proprietary and customer specifications. MIL-I-17563 tests the impregnation sealant. MIL-I-17563C demonstrates a sealant is compatible with the application and that the sealant will not degrade or fail over the life of the part. MIL-STD-276A tests the impregnation process. MIL-STD-276A provides the standards for processing to seal parts and testing process effectiveness. \nProcess.\nThe vacuum impregnation process seals internal leak paths to make it leak free and suitable for use. In the course of sealing castings against porosity, the parts would be processed through the following four stations:\nVacuum impregnation should be done prior to final assembly. Specifically for metal castings, vacuum impregnation should be done after final machining. Final machining may expose any porosity, creating a leak path. These paths can cause fluids and gases to leak from the casting, causing it to be non-conforming and unusable.\nCommon Applications.\nPorosity is inherent to most manufacturing processes. Porosity is only considered a defect if it is interconnected and creates a leak path can affect the part's structural integrity and performance. Vacuum impregnation seals porosity and leak paths for the following reasons.\nSeal Leak Paths.\nThis is the main reason why vacuum impregnation is used on any material-die cast, powder metal, plastic, wire harnesses. Vacuum impregnation prevents fluids or gases from leaking by sealing the porosity and leak paths. If the leak paths are not sealed, then fluids or gases may leak from the part. \nImprove Machinability.\nImpregnation is used to improve machinability on powder metallurgy. Secondary machine operations, such as drilling, tapping, or cutting, are only marginally successful because voids between the particles cause tool chatter, reducing tool life and finish quality. Vacuum impregnation stabilizes and supports the individual powdered metal granules during machining. Vacuum impregnation improves machinability by making it more efficient, eliminating tool chatter, and improving the machined finish.\nProhibit Corrosion.\nPlating operations submerge the parts in acid solutions. The residual acid can seep into the porosity, which causes corrosion. Sealing the components before plating eliminates corrosion.\nEnhance Secondary Finishing.\nThe porosity may absorb oils, fluids, deburring fluids, pre-plating cleaners, and acids. If not sealed, then any gases or fluids may affect the finish by outgassing or bleeding out. Sealing the leak paths before secondary finishes will eliminate any failure mode that could develop from outgassing, chemical compatibility, or bleed out of pretreatments.\nImprove Part Integrity.\nVacuum impregnation can be used to part the integrity of additive manufacturing parts. An additive manufacturing part is not as dense — and thus not as strong — as a part made from traditional manufacturing processes. Vacuum impregnation can be used to strengthen the material. As the vacuum impregnation sealant cures within the perforations, it creates a bond between the part layers. This enhances the part by increasing density.\nCommon Materials.\nAdditive Manufacturing.\nParts created through the additive manufacturing process are susceptible to the same porosity that plagues those created through more traditional methods. The porosity is inherent to the properties of the material and technology. The two primary materials that vacuum impregnation seals are plastic and sintered metal. \nDie Castings.\nDie castings and permanent mold castings commonly contain internal porosity. This porosity is generally localized to the deepest cross-sections of the part and does not extend to the outer skin. However, if the part is also machined, the internal porosity will be exposed and the part will leak if pressurized. Machined die castings that need to hold fluids (intake manifolds, coolant connectors, transmission cases, pump housings and fluid power components) are routinely sealed for life using acrylic resins. Because the sealant is internal to the part, the exterior dimensions and appearance of the part are unchanged.\nElectronics.\nIn these parts, metal pins and wires are embedded in the plastic housing. When the parts experience heat during manufacturing or normal use, the plastic and metal expand at different rates. This expansion creates microscopic voids between the materials. While these leak paths are unavoidable, they can cause a field failure if not sealed. \nPowder metallurgy.\nPowder metallurgy (PM) components are sealed for four main reasons.\nThe first is that PM parts are sealed to prevent fluids or gases from leaking under pressure. PM applications for compressed air, fuel handling or hydraulic housings are common and effective; however, they must be sealed first. If not sealed, then fluids or gases will leak from the part. Sealing the parts will not change the component's dimensional or functional characteristics.\nPM parts are sealed prior to plating and to reduce internal corrosion. Plating operations typically involve submerging the parts in acid solutions. After plating, residual acid internal to the part can promote corrosion and/or preclude an acceptable plating finish. The solution to this problem is to seal the internal voids prior to plating. As explained above, the porosity is saturated with monomer and is then rinsed completely clear of the surface. The resin cures to a durable polymer. Thus, the exposed surface metal is free to be plated while the interior spaces are sealed dry.\nPowder metal is also impregnated to enhance maintainability. PM parts are generally difficult to machine and some compositions may not be machinable without ruining the cutting tool. Secondary machine operations, such as drilling, tapping, or cutting, are impaired as the voids between the particles cause tool chatter, reducing tool life and degrading the finish quality. Vacuum impregnation stabilizes and supports the individual powdered metal granules during machining. This improves machinability by making it more efficient, eliminating tool chatter, and improving the machined finish. \nPowder metal porosity absorbs oils, fluids, deburring fluids, pre-plating cleaners, and acids. If the porosity is not sealed, fluids may bleed out and negatively affect the finish. Sealing the porosity before secondary finishes will eliminate any failure mode that could develop from bleed out of pretreatments.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "1374117", "revid": "68043", "url": "https://en.wikipedia.org/wiki?curid=1374117", "title": "Avery Weigh-Tronix", "text": "Avery Weigh-Tronix is a subsidiary of Illinois Tool Works specialising in industrial weighing machines. Its headquarters stands on the site of the Soho Foundry in Smethwick, West Midlands, England. The company additionally has a United States-based manufacturing and retail manufacturing plant. The company is one of the largest suppliers of weighing devices. The company is registered as Avery Weigh-Tronix, Ltd. in the UK and Avery Weigh-Tronix, LLC in the US.\nHistory.\nThe company was formed in June 2000 when the U.S.-based weighing company Weigh-Tronix acquired the Avery Berkel group of companies. Avery Berkel was the result of the merger between GEC Avery (formally W & T Avery) and Berkel.\nAvery Weigh-Tronix was the parent company in the group with every other company (including Avery Berkel) being brands of Avery Weigh-Tronix. Avery Weigh-Tronix was used as the industrial brand of the company.\nIn September 2007, Illinois Tool Works acquired Avery Berkel from Avery Weigh-Tronix.\nIn September 2008, Illinois Tool Works acquires Avery Weigh-Tronix, Avery Berkel and Avery Weigh-Tronix were kept separate with Avery Weigh-Tronix focusing more on the industrial and commercial and Avery Berkel focusing on retail.", "Engineering,_Manufacturing": 0.9999645948, "qwen": "Yes"}
{"id": "1378439", "revid": "18010125", "url": "https://en.wikipedia.org/wiki?curid=1378439", "title": "Whisker (metallurgy)", "text": "Metal whiskering is a phenomenon which occurs in electrical devices when metals form long whisker-like projections over time. Tin whiskers were noticed and documented in the vacuum tube era of electronics early in the 20th century in equipment that used pure, or almost pure, tin solder in their production. It was noticed that small metal hairs or tendrils grew between metal solder pads, causing short circuits. Metal whiskers form in the presence of compressive stress. Germanium, zinc, cadmium, and even lead whiskers have been documented. Many techniques are used to mitigate the problem, including changes to the annealing process (heating and cooling), the addition of elements like copper and nickel, and the inclusion of conformal coatings. Traditionally, lead has been added to slow down whisker growth in tin-based solders.\nFollowing the Restriction of Hazardous Substances Directive (RoHS), the European Union banned the use of lead in most consumer electronic products from 2006 due to health problems associated with lead and the \"high-tech trash\" problem, leading to a re-focusing on the issue of whisker formation in lead-free solders.\nMechanism.\nMetal whiskering is a crystalline metallurgical phenomenon involving the spontaneous growth of tiny, filiform hairs from a metallic surface. The effect is primarily seen on elemental metals but also occurs with alloys.\nThe mechanism behind metal whisker growth is not well understood, but seems to be encouraged by compressive mechanical stresses including:\nMetal whiskers differ from metallic dendrites in several respects: dendrites are fern-shaped and grow across the surface of the metal, while metal whiskers are hair-like and project normal to the surface. Dendrite growth requires moisture capable of dissolving the metal into a solution of metal ions, which are then redistributed by electromigration in the presence of an electromagnetic field. While the precise mechanism for whisker formation remains unknown, it is known that whisker formation does not require either dissolution of the metal or the presence of an electromagnetic field.\nEffects.\nWhiskers can cause short circuits and arcing in electrical equipment. The phenomenon was discovered by telephone companies in the late 1940s and it was later found that the addition of lead to tin solder provided mitigation. The European Restriction of Hazardous Substances Directive (RoHS), which took effect on July 1, 2006, restricted the use of lead in various types of electronic and electrical equipment. This has driven the use of lead-free alloys with a focus on preventing whisker formation . Others have focused on the development of oxygen-barrier coatings to prevent whisker formation.\nAirborne zinc whiskers have been responsible for increased system failure rates in computer server rooms. Zinc whiskers grow from galvanized (electroplated) metal surfaces at a rate of up to a millimeter per year with a diameter of a few micrometers. Whiskers can form on the underside of zinc electroplated floor tiles on raised floors. These whiskers can then become airborne within the floor plenum when the tiles are disturbed, usually during maintenance. Whiskers can be small enough to pass through air filters and can settle inside equipment, resulting in short circuits and system failure.\nTin whiskers do not have to be airborne to damage equipment, as they are typically already growing directly in the environment where they can produce short circuits, i.e., the electronic equipment itself. At frequencies above 6 GHz or in fast digital circuits, tin whiskers can act like miniature antennas, affecting the circuit impedance and causing reflections. In computer disk drives they can break off and cause head crashes or bearing failures. Tin whiskers often cause failures in relays and have been found upon examination of failed relays in nuclear power facilities. Pacemakers have been recalled due to tin whiskers. Research has also identified a particular failure mode for tin whiskers in vacuum (such as in space), where in high-power components a short-circuiting tin whisker is ionized into a plasma that is capable of conducting hundreds of amperes of current, massively increasing the damaging effect of the short circuit. The possible increase in the use of pure tin in electronics due to the RoHS directive drove JEDEC and IPC to release a tin whisker acceptance testing standard and mitigation practices guideline intended to help manufacturers reduce the risk of tin whiskers in lead-free products.\nSilver whiskers often appear in conjunction with a layer of silver sulfide, which forms on the surface of silver electrical contacts operating in an atmosphere rich in hydrogen sulfide and high humidity. Such atmospheres can exist in sewage treatment plants and paper mills.\nWhiskers over 20 µm in length were observed on gold-plated surfaces and noted in a 2003 NASA internal memorandum.\nThe effects of metal whiskering were chronicled on History Channel's program \"Engineering Disasters\" 19.\nMitigation and elimination.\nSeveral approaches are used to reduce or eliminate whisker growth, with ongoing research in the area.\nConformal coatings.\nConformal compound coatings stop the whiskers from penetrating a barrier, reaching a nearby termination and forming a short.\nAltering plating chemistry.\nTermination finishes of nickel, gold or palladium have been shown to eliminate whisker formation in controlled trials.\nTin whisker examples and incidents.\nGalaxy IV.\nGalaxy IV was a telecommunications satellite that was disabled and lost due to short circuits caused by tin whiskers in 1998. It was initially thought that space weather contributed to the failure, but later it was discovered that a conformal coating had been misapplied, allowing whiskers formed in the pure tin plating to find their way through a missing coating area, causing a failure of the main control computer. The manufacturer, Hughes, has moved to nickel plating, rather than tin, to reduce the risk of whisker growth. The trade-off has been an increase in weight, adding per payload.\nMillstone Nuclear Power Plant.\nOn April 17, 2005, the Millstone Nuclear Power Plant in Connecticut was shut down due to a \"false alarm\" that indicated an unsafe pressure drop in the reactor's steam system when the steam pressure was actually nominal. The false alarm was caused by a tin whisker that short circuited the logic board that was responsible for monitoring the steam pressure lines in the power plant.\nToyota accelerator position sensors false positive.\nIn September 2011, three NASA investigators claimed that the tin whiskers they identified on the accelerator position sensors of sampled models of Toyota Camry could contribute to the \"stuck accelerator\" crashes affecting certain Toyota models during 2005–2010. This contradicted an earlier 10-month joint investigation by the National Highway Traffic Safety Administration (NHTSA) and a large group of other NASA researchers that found no electronic defects.\nHowever, in 2012 NHTSA maintained: \"We do not believe that tin whiskers are a plausible explanation for these incidents...[the likely cause was] pedal misapplication.\"\nToyota also maintains that tin whiskers were not the cause of any stuck accelerator issues: \"In the words of U.S. Transportation Secretary Ray LaHood, 'The verdict is in. There is no electronic-based cause for unintended high-speed acceleration in Toyotas. Period. According to a Toyota press release, \"no data indicates that tin whiskers are more prone to occur in Toyota vehicles than any other vehicle in the marketplace.\" Toyota also states that \"their systems are designed to reduce the risk that tin whiskers will form in the first place.\"", "Engineering,_Manufacturing": 0.9998846054, "qwen": "Yes"}
{"id": "3909349", "revid": "42463168", "url": "https://en.wikipedia.org/wiki?curid=3909349", "title": "Qinghai Huading Industrial", "text": "Qinghai Huading Industrial Co., Ltd. known as Qinghai Huading or just QHHD, is a holding company established in 1998 and listed on the Shanghai Stock Exchange in 2000. As of 12 June 2015, the company has a market capitalization of 4.682 billion CNY and employs over 4,000 staffs. Through its various subsidiaries, the company is involved mainly in the manufacturing and distribution of machine tools, gearboxes, food machineries, elevator components and LED lightings.\nOperations.\nThe group's core business is the manufacturing of machine tools. As of 2012, Qinghai Huading is the domestic market leader in horizontal machine tools in terms of output volume and has over 90% domestic market share in rail road specific machine tools.\nDirectors & Officers.\n\"Officers and Directors data as of Feb 17 2013\"", "Engineering,_Manufacturing": 0.9965848923, "qwen": "Yes"}
{"id": "3920625", "revid": "20958214", "url": "https://en.wikipedia.org/wiki?curid=3920625", "title": "List of integrated circuit packaging types", "text": "Integrated circuits are put into protective packages to allow easy handling and assembly onto printed circuit boards and to protect the devices from damage. A very large number of different types of package exist. Some package types have standardized dimensions and tolerances, and are registered with trade industry associations such as JEDEC and Pro Electron. Other types are proprietary designations that may be made by only one or two manufacturers. Integrated circuit packaging is the last assembly process before testing and shipping devices to customers.\nOccasionally specially-processed integrated circuit dies are prepared for direct connections to a substrate without an intermediate header or carrier. In flip chip systems the IC is connected by solder bumps to a substrate. In beam-lead technology, the metallized pads that would be used for wire bonding connections in a conventional chip are thickened and extended to allow external connections to the circuit. Assemblies using \"bare\" chips have additional packaging or filling with epoxy to protect the devices from moisture.\nThrough-hole packages.\nThrough-hole technology uses holes drilled through the printed circuit board (PCB) for mounting the components. The component has leads that are soldered to pads on the PCB to electrically and mechanically connect them to the PCB.\nSurface mount.\nChip on board is a packaging technique that directly connects a die to a PCB, without an interposer or lead frame.\nChip carrier.\nA chip carrier is a rectangular package with contacts on all four edges. Leaded chip carriers have metal leads wrapped around the edge of the package, in the shape of a letter J. Leadless chip carriers have metal pads on the edges. Chip carrier packages may be made of ceramic or plastic and are usually secured to a printed circuit board by soldering, though sockets can be used for testing.\nBall grid array.\nBall grid array (BGA) uses the underside of the package to place pads with balls of solder in grid pattern as connections to PCB.\nPackage dimensions.\nAll measurements below are given in mm. To convert mm to mils, divide mm by 0.0254 (i.e., 2.54 mm / 0.0254 = 100 mil).\nMulti-chip packages.\nA variety of techniques for interconnecting several chips within a single package have been proposed and researched:\nBy terminal count.\nSurface-mount components are usually smaller than their counterparts with leads, and are designed to be handled by machines rather than by humans. The electronics industry has standardized package shapes and sizes (the leading standardisation body is JEDEC).\nThe codes given in the chart below usually tell the length and width of the components in tenths of millimeters or hundredths of inches. For example, a metric 2520 component is 2.5 mm by 2.0 mm which corresponds roughly to 0.10 inches by 0.08 inches (hence, imperial size is 1008). Exceptions occur for imperial in the two smallest rectangular passive sizes. The metric codes still represent the dimensions in mm, even though the imperial size codes are no longer aligned. Problematically, some manufacturers are developing metric 0201 components with dimensions of , but the imperial 01005 name is already being used for the package. These increasingly small sizes, especially 0201 and 01005, can sometimes be a challenge from a manufacturability or reliability perspective.\nTwo-terminal packages.\nRectangular passive components.\nMostly resistors and capacitors.\nMetal electrode leadless face (MELF).\nMostly resistors and diodes; barrel shaped components, dimensions do not match those of rectangular references for identical codes.\nDO-214.\nCommonly used for rectifier, Schottky, and other diodes.\nPackages with more than six terminals.\nNon-packaged devices.\nAlthough surface-mount, these devices require specific process for assembly.\nThere are often subtle variations in package details from manufacturer to manufacturer, and even though standard designations are used, designers need to confirm dimensions when laying out printed circuit boards.", "Engineering,_Manufacturing": 0.9997705817, "qwen": "Yes"}
{"id": "3922021", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=3922021", "title": "Robot calibration", "text": "Robot calibration is a process used to improve the accuracy of robots, particularly industrial robots which are highly repeatable but not accurate. Robot calibration is the process of identifying certain parameters in the kinematic structure of an industrial robot, such as the relative position of robot links. Depending on the type of errors modeled, the calibration can be classified in three different ways. Level-1 calibration only models differences between actual and reported joint displacement values, (also known as mastering). Level-2 calibration, also known as kinematic calibration, concerns the entire geometric robot calibration which includes angle offsets and joint lengths. Level-3 calibration, also called a non-kinematic calibration, models errors other than geometric defaults such as stiffness, joint compliance, and friction. Often Level-1 and Level-2 calibration are sufficient for most practical needs.\nParametric robot calibration is the process of determining the actual values of kinematic and dynamic parameters of an industrial robot (IR). Kinematic parameters describe the relative position and orientation of links and joints in the robot while the dynamic parameters describe arm and joint masses and internal friction.\nNon-parametric robot calibration circumvents the parameter identification. Used with serial robots, it is based on the direct compensation of mapped errors in the workspace. Used with parallel robots, non-parametric calibration can be performed by the transformation of the configuration space.\nRobot calibration can remarkably improve the accuracy of robots programmed offline. A calibrated robot has a higher absolute as well as relative positioning accuracy compared to an uncalibrated one; i.e., the real position of the robot end effector corresponds better to the position calculated from the mathematical model of the robot. Absolute positioning accuracy is particularly relevant in connection with robot exchangeability and off-line programming of precision applications. Besides the calibration of the robot, the calibration of its tools and the workpieces it works with (the so-called \"cell calibration\") can minimize occurring inaccuracies and improve process security.\nAccuracy criteria and error sources.\nThe international standard ISO 9283 sets different performance criteria for industrial robots and suggests test procedures in order to obtain appropriate parameter values. The most important criteria, and also the most commonly used, are pose accuracy (AP) and pose repeatability (RP). Repeatability is particularly important when the robot is moved towards the command positions manually (\"Teach-In\"). If the robot program is generated by a 3D simulation (\"off-line programming\"), absolute accuracy is vital, too. Both are generally influenced negatively by kinematic factors. Here especially the joint offsets and deviations in lengths and angles between the individual robot links take effect.\nMeasurement systems.\nThere exist different possibilities for pose measurement with industrial robots, e.g. touching reference parts, using supersonic distance sensors, laser interferometry, theodolites, calipers or laser triangulation. Furthermore, there are camera systems which can be attached in the robot's cell or at the IR mounting plate and acquire the pose of a reference object. Measurement and calibration systems are made by such companies as Bluewrist, Dynalog, RoboDK, FARO Technologies, Creaform, Leica, Metris, Metronor, Wiest, Teconsult and Automated Precision.\nMathematical principles.\nThe robot errors gathered by pose measurements can be minimized by numerical optimization. For kinematic calibration, a complete kinematical model of the geometric structure must be developed, whose parameters can then be calculated by mathematical optimization. The common system behaviour can be described with the vector model function as well as input and output vectors (see figure).\nThe variables \"k, l, m, n\" and their derivates describe the dimensions of the single vector spaces. Minimization of the residual error \"r\" for identification of the optimal parameter vector \"p\" follows from the difference between both output vectors using the Euclidean norm.\nFor solving the kinematical optimization problems least-squares descent methods are convenient, e.g. a modified quasi-Newton method. This procedure supplies corrected kinematical parameters for the measured machine, which then, for example, can be used to update the system variables in the controller to adapt the used robot model to the real kinematics.\nResults.\nThe positioning accuracy of industrial robots varies by manufacturer, age, and robot type. Using kinematic calibration, these errors can be reduced to less than a millimeter in most cases. An example of this is shown in the figure to the right.\nAccuracy of 6-axis industrial robots can improved by a factor of 10.\nAccuracy of parallel robots after calibration can be as low as a tenth of a millimeter.\nSample applications.\nIn the industry, there is a general trend towards substitution of machine tools and special machines by industrial robots for certain manufacturing tasks whose accuracy demands can be fulfilled by calibrated robots. Through simulation and off-line programming, it is possible to easily accomplish complex programming tasks, such as robot machining. However, contrary to the teach programming method, good accuracy as well as repeatability is required.\nIn the figure, a current example is shown: In-line measurement in automotive manufacturing, where the common \"measurement tunnel\" used for 100% inspection with many expensive sensors are partly replaced by industrial robots that carry only one sensor each. This way the total costs of a measurement cell can be reduced significantly. The station can also be re-used after a model change by simple re-programming without mechanical adaptations.\nFurther examples for precision applications are robot-guided hemming in car body manufacturing, assembly of mobile phones, drilling, riveting and milling in the aerospace industry, and increasingly in medical applications.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "7794505", "revid": "45382375", "url": "https://en.wikipedia.org/wiki?curid=7794505", "title": "SPEED2000", "text": "SPEED2000 is a software package designed for electromagnetic simulation for the analysis and design of high-speed electronic systems. It combines an electromagnetic field solver with circuit and transmission line simulations which allows it to compute dynamic electromagnetic interactions within integrated circuits. SPEED2000 provides electrical analysis of integrated circuit (IC) packages and printed circuit boards (PCBs). It is developed and marketed by Sigrity, Inc.\nHistory.\nThe algorithms on which SPEED2000 is based were initially developed by Dr. Jiayuan Fang (then associate professor of Electrical Engineering at Binghamton University) and his students. The electromagnetic simulation algorithms that he developed were 1000 times faster previous methods.\nDr. Fang patented the algorithms (see below) and founded a company called Sigrity, Inc. to further develop the software. He eventually left Binghamton University to work on his software full-time. The rights to the initial patents are owned by Binghamton University and the royalties provide funding for current research efforts at the university.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "7796225", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=7796225", "title": "Industrial technology", "text": "Industrial technology is the use of engineering and manufacturing technology to make production faster, simpler, and more efficient. The industrial technology field employs creative and technically proficient individuals who can help a company achieve efficient and profitable productivity.\nIndustrial technology programs typically include instruction in optimization theory, human factors, organizational behavior, industrial processes, industrial planning procedures, computer applications, and report and presentation preparation.\nPlanning and designing manufacturing processes and equipment is the main aspect of being an industrial technologist. An industrial technologist is often responsible for implementing certain designs and processes.\nAccreditation and certification.\nThe USA-based Association of Technology, Management, and Applied Engineering (ATMAE), accredits selected collegiate programs in Industrial Technology in the USA. An instructor or graduate of an Industrial Technology program may choose to become a Certified Technology Manager (CTM) by sitting for a rigorous exam administered by ATMAE covering Production Planning & Control, Safety, Quality, and Management/Supervision.\nATMAE program accreditation is recognized by the Council for Higher Education Accreditation (CHEA) for accrediting Industrial Technology programs. CHEA recognizes ATMAE in the U.S. for accrediting associate, baccalaureate, and master's degree programs in technology, applied technology, engineering technology, and technology-related disciplines delivered by national or regional accredited institutions in the United States.(2011) Industrial technology is also one of the largest industries used.\nKnowledge base.\n\"A career in industrial technology typically entails formal education from an accredited college or university. Opportunities are available to professionals with all levels of education. Those who hold associate degrees typically qualify for the entry-level technician and technologist positions, such as in the maintenance and operation of machinery. Bachelor's degree-holders could fill management and engineering positions, such as plant manager, production supervisor and quality systems engineering technologist. A graduate degree in industrial technology could qualify individuals for jobs in research, teaching and upper-level management\".\nIndustrial Technology includes wide-ranging subject matter and could be viewed as an amalgamation of industrial engineering and business topics with a focus on practicality and management of technical systems with less focus on actual engineering of those systems.\nTypical curriculum at a four-year university might include courses on manufacturing process, technology and impact on society, mechanical and electronic systems, quality assurance and control, materials science, packaging, production and operations management, and manufacturing facility planning and design. In addition, the Industrial Technologist may have exposure to more vocational-style education in the form of courses on CNC manufacturing, welding, and other tools-of-the-trade in manufacturing.\nIndustrial technologist.\nIndustrial technology program graduates obtain a majority of positions which are applied engineering and/or management oriented. Since \"industrial technologist\" is not a common job title in the United States, the actual bachelor's degree or associate degree earned by the individual is obscured by the job title he/she receives. Typical job titles for industrial technologists having a bachelor's degree include quality systems engineer, manufacturing engineer, industrial engineer, plant manager, production supervisor, etc. Typical job titles for industrial technologists having a two-year associate degree include project technologist, manufacturing technologist, process technologist, etc.\nA technologist curriculum may focus or specialize in a certain technical area of study. Examples of this includes electronics, manufacturing, construction, graphics, automation/robotics, CADD, nanotechnology, aviation, etc.\nTechnological development in industry.\nA major subject of study is technological development in industry. This has been defined as:\nStudies in this area often employ a multi-disciplinary research methodology and shade off into the wider analysis of business and economic growth (development, performance). The studies are often based on a mixture of industrial field research and desk-based data analysis and aim to be of interest and use to practitioners in business management and investment (etc.) as well as academics. In engineering, construction, textiles, food and drugs, chemicals and petroleum, and other industries, the focus has been on not only the nature and factors facilitating and hampering the introduction and utilization of new technologies but also the impact of new technologies on the production organization (etc.) of firms and various social and other wider aspects of the technological development process.\nHow and When Technological development in industry Performed :", "Engineering,_Manufacturing": 0.9999911785, "qwen": "Yes"}
{"id": "7799328", "revid": "161958", "url": "https://en.wikipedia.org/wiki?curid=7799328", "title": "Scaif", "text": "A scaif is a polishing wheel infused with a mixture of olive oil and diamond dust used in the diamond cutting industry. It was invented in 1456 by Lodewyk van Bercken. \nWith the scaif, it became possible to polish all the facets of the diamond symmetrically at angles that reflected the light best. This invention revolutionized the diamond cutting industry and correspondingly, much increased the popularity of diamonds.\nThe scaif consists of a hard disk, parallel to the floor. The disk looks like and is rotated in the same way as a potter's wheel. On the top surface a film of olive oil and diamond dust is placed. Surrounding the disk is a circular frame to catch the oil that is spun off as the disk is rotated. \nHovering just above the surface of the disk is a mechanical arm to hold the diamond. It can be finely adjusted, to move the diamond into the exact position needed for polishing the facets. As the facets are polished more diamond dust is produced, replenishing the supply.", "Engineering,_Manufacturing": 0.97785151, "qwen": "Yes"}
{"id": "20771318", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=20771318", "title": "Buckeye Manufacturing Company", "text": "The Buckeye Manufacturing Company was a company noted for manufacturing gasoline engines and farm implements. It manufactured the engines for its sister company, the Union Automobile Company.\nIn time the Lambert founded automobile related subsidiary companies such as the Union Automobile Company, the Lambert Automobile Company, and the Lambert Gas and Gasoline Engine Company. Buckeye Manufacturing Company manufactured the components of the cars assembled by these subsidiaries. The company later produced automobiles and it continued until 1917.\nHistory.\nA single Buckeye gasoline buggy automobile was built by the company in 1890, and offered for sale in 1891, though none were produced. ", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1514159", "revid": "41840956", "url": "https://en.wikipedia.org/wiki?curid=1514159", "title": "Tex Corp", "text": "Tex Corp is an Indian multinational manufacturer of zippers, sliders and other fastening products. Headquartered in Gurgaon, it supplies global fashion retailers primarily in Europe and the United States.\nBackground.\nFormed in New Delhi in 1987 by a group of Indian Institutes of Management alumni, Tex is one of the largest manufacturers and exporters of zipper and fastening products for the apparel industry. It has two manufacturing facilities in India and one each in Bangladesh and Vietnam, becoming the first Indian owned multinational zipper manufacturing organization. Tex's business group also has interests in apparel manufacturing and renewable energy.\nAmong Tex's clients are the Gap, Macy's, Kohl's, Express, Target, Talbots, Belk, HBC, H&M, Debenhams, Next, Tesco and Matalan. Tex's products are delivered directly to its customers' manufacturing facilities located primarily in the Indian Subcontinent, South-East Asia, Africa and Europe.\nTex adheres to the International Organization for Standardization (ISO)9001:2008 standard. Tex is also an Oeko-Tex Product Class 1 and Eco-tex certified organization. Its products are Consumer Product Safety Improvement Act and Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) compliant.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "440996", "revid": "32762897", "url": "https://en.wikipedia.org/wiki?curid=440996", "title": "Arc welding", "text": "Arc welding is a welding process that is used to join metal to metal by using electricity to create enough heat to melt metal, and the melted metals, when cool, result in a binding of the metals. It is a type of welding that uses a welding power supply to create an electric arc between a metal stick (\"electrode\") and the base material to melt the metals at the point of contact. Arc welding power supplies can deliver either direct (DC) or alternating (AC) current to the work, while consumable or non-consumable electrodes are used.\nThe welding area is usually protected by some type of shielding gas (e.g. an inert gas), vapor, or slag. Arc welding processes may be manual, semi-automatic, or fully automated. First developed in the late part of the 19th century, arc welding became commercially important in shipbuilding during the Second World War. Today it remains an important process for the fabrication of steel structures and vehicles.\nPower supplies.\nTo supply the electrical energy necessary for arc welding processes, a number of different power supplies can be used. The most common classification is constant current power supplies and constant voltage power supplies. In arc welding, the voltage is directly related to the length of the arc, and the current is related to the amount of heat input. Constant current power supplies are most often used for manual welding processes such as gas tungsten arc welding and shielded metal arc welding, because they maintain a relatively constant current even as the voltage varies. This is important because in manual welding, it can be difficult to hold the electrode perfectly steady, and as a result, the arc length and thus voltage tend to fluctuate. Constant voltage power supplies hold the voltage constant and vary the current, and as a result, are most often used for automated welding processes such as gas metal arc welding, flux cored arc welding, and submerged arc welding. In these processes, arc length is kept constant, since any fluctuation in the distance between the wire and the base material is quickly rectified by a large change in current. For example, if the wire and the base material get too close, the current will rapidly increase, which in turn causes the heat to increase and the tip of the wire to melt, returning it to its original separation distance. Under normal arc length conditions, a constant current power supply with a stick electrode operates at about 20 volts.\nThe direction of current used in arc welding also plays an important role in welding. Consumable electrode processes such as shielded metal arc welding and gas metal arc welding generally use direct current, but the electrode can be charged either positively or negatively. In general, the positively charged anode will have a greater heat concentration (around 60%). \"Note that for stick welding in general, DC+ polarity is most commonly used. It produces a good bead profile with a higher level of penetration. DC- polarity results in less penetration and a higher electrode melt-off rate. It is sometimes used, for example, on thin sheet metal in an attempt to prevent burn-through.\" \"With few exceptions, electrode-positive (reversed polarity) results in deeper penetration. Electrode-negative (straight polarity) results in faster melt-off of the electrode and, therefore, faster deposition rate.\" Non-consumable electrode processes, such as gas tungsten arc welding, can use either type of direct current (DC), as well as alternating current (AC). With direct current however, because the electrode only creates the arc and does not provide filler material, a positively charged electrode causes shallow welds, while a negatively charged electrode makes deeper welds. Alternating current rapidly moves between these two, resulting in medium-penetration welds. One disadvantage of AC, the fact that the arc must be re-ignited after every zero crossing, has been addressed with the invention of special power units that produce a square wave pattern instead of the normal sine wave, eliminating low-voltage time after the zero crossings and minimizing the effects of the problem.\nDuty cycle is a welding equipment specification which defines the number of minutes, within a 10-minute period, during which a given arc welder can safely be used. For example, an 80 A welder with a 60% duty cycle must be \"rested\" for at least 4 minutes after 6 minutes of continuous welding. Failure to observe duty cycle limitations could damage the welder. Commercial- or professional-grade welders typically have a 100% duty cycle.\nConsumable electrode methods.\nOne of the most common types of arc welding is shielded metal arc welding (SMAW), which is also known as manual metal arc welding (MMAW) or stick welding. An electric current is used to strike an arc between the base material and a consumable electrode rod or \"stick\". The electrode rod is made of a material that is compatible with the base material being welded and is covered with a flux that gives off vapors that serve as a shielding gas and provide a layer of slag, both of which protect the weld area from atmospheric contamination. The electrode core itself acts as filler material, making a separate filler unnecessary. The process is very versatile, requiring little operator training and inexpensive equipment. However, weld times are rather slow, since the consumable electrodes must be frequently replaced and because slag, the residue from the flux, must be chipped away after welding. Furthermore, the process is generally limited to welding ferrous materials, though specialty electrodes have made possible the welding of cast iron, nickel, aluminum, copper and other metals. The versatility of the method makes it popular in a number of applications including repair work and construction.\nGas metal arc welding (GMAW), commonly called \"MIG\" (for \"metal/inert-gas\"), is a semi-automatic or automatic welding process with a continuously fed consumable wire acting as both electrode and filler metal, along with an inert or semi-inert shielding gas flowed around the wire to protect the weld site from contamination. Constant voltage, direct current power source is most commonly used with GMAW, but constant current alternating current are used as well. With continuously fed filler electrodes, GMAW offers relatively high welding speeds; however the more complicated equipment reduces convenience and versatility in comparison to the SMAW process. Originally developed for welding aluminum and other non-ferrous materials in the 1940s, GMAW was soon economically applied to steels. Today, GMAW is commonly used in industries such as the automobile industry for its quality, versatility and speed. Because of the need to maintain a stable shroud of shielding gas around the weld site, it can be problematic to use the GMAW process in areas of high air movement such as outdoors.\nFlux-cored arc welding (FCAW) is a variation of the GMAW technique. FCAW wire is actually a fine metal tube filled with powdered flux materials. An externally supplied shielding gas is sometimes used, but often the flux itself is relied upon to generate the necessary protection from the atmosphere. The process is widely used in construction because of its high welding speed and portability.\nSubmerged arc welding (SAW) is a high-productivity welding process in which the arc is struck beneath a covering layer of granular flux. This increases arc quality, since contaminants in the atmosphere are blocked by the flux. The slag that forms on the weld generally comes off by itself and, combined with the use of a continuous wire feed, the weld deposition rate is high. Working conditions are much improved over other arc welding processes since the flux hides the arc and no smoke is produced. The process is commonly used in industry, especially for large products. As the arc is not visible, it is typically automated. SAW is only possible in the 1F (flat fillet), 2F (horizontal fillet), and 1G (flat groove) positions.\nNon-consumable electrode methods.\nGas tungsten arc welding (GTAW), or \"tungsten/inert-gas\" (TIG) welding, is a manual welding process that uses a non-consumable electrode made of tungsten, an inert or semi-inert gas mixture, and a separate filler material. Especially useful for welding thin materials, this method is characterized by a stable arc and high quality welds, but it requires significant operator skill and can only be accomplished at relatively low speeds. It can be used on nearly all weldable metals, though it is most often applied to stainless steel and light metals. It is often used when quality welds are extremely important, such as in bicycle, aircraft and marine applications.\nA related process, plasma arc welding, also uses a tungsten electrode but uses plasma gas to make the arc. The arc is more concentrated than the GTAW arc, making transverse control more critical and thus generally restricting the technique to a mechanized process. Because of its stable current, the method can be used on a wider range of material thicknesses than can the GTAW process and is much faster. It can be applied to all of the same materials as GTAW except magnesium; automated welding of stainless steel is one important application of the process. A variation of the process is plasma cutting, an efficient steel cutting process.\nOther arc welding processes include atomic hydrogen welding, carbon arc welding, electroslag welding, electrogas welding, and stud arc welding.\nCorrosion issues.\nSome materials, notably high-strength steels, aluminum, and titanium alloys, are susceptible to hydrogen embrittlement. If the electrodes used for welding contain traces of moisture, the water decomposes in the heat of the arc and the liberated hydrogen enters the lattice of the material, causing its brittleness. Stick electrodes for such materials, with special low-hydrogen coating, are delivered in sealed moisture-proof packaging. New electrodes can be used straight from the can, but when moisture absorption may be suspected, they have to be dried by baking (usually at ) in a drying oven. Flux used has to be kept dry as well.\nSome austenitic stainless steels and nickel-based alloys are prone to intergranular corrosion. When subjected to temperatures around for too long a time, chromium reacts with carbon in the material, forming chromium carbide and depleting the crystal edges of chromium, impairing their corrosion resistance in a process called sensitization. Such sensitized steel undergoes corrosion in the areas near the welds where the temperature-time was favorable for forming the carbide. This kind of corrosion is often termed weld decay.\nKnifeline attack (KLA) is another kind of corrosion affecting welds, impacting steels stabilized by niobium. Niobium and niobium carbide dissolves in steel at very high temperatures. At some cooling regimes, niobium carbide does not precipitate, and the steel then behaves like unstabilized steel, forming chromium carbide instead. This affects only a thin zone several millimeters wide in the very vicinity of the weld, making it difficult to spot and increasing the corrosion speed. Structures made of such steels have to be heated in a whole to about , when the chromium carbide dissolves and niobium carbide forms. The cooling rate after this treatment is not important.\nFiller metal (electrode material) improperly chosen for the environmental conditions can make them corrosion-sensitive as well. There are also issues of galvanic corrosion if the electrode composition is sufficiently dissimilar to the materials welded, or the materials are dissimilar themselves. Even between different grades of nickel-based stainless steels, corrosion of welded joints can be severe, despite that they rarely undergo galvanic corrosion when mechanically joined.\nSafety issues.\nWelding can be a dangerous and unhealthy practice without the proper precautions; however, with the use of new technology and proper protection the risks of injury or death associated with welding can be greatly reduced.\nHeat, fire, and explosion hazard.\nBecause many common welding procedures involve an open electric arc or flame, the risk of burns from heat and sparks is significant. To prevent them, welders wear protective clothing in the form of heavy leather gloves and protective long sleeve jackets to avoid exposure to extreme heat, flames, and sparks. The use of compressed gases and flames in many welding processes also pose an explosion and fire risk; some common precautions include limiting the amount of oxygen in the air and keeping combustible materials away from the workplace.\nEye damage.\nExposure to the brightness of the weld area leads to a condition called arc eye in which ultraviolet light causes inflammation of the cornea and can burn the retinas of the eyes. Welding goggles and helmets with dark face plates—much darker than those in sunglasses or oxy-fuel goggles—are worn to prevent this exposure. In recent years, new helmet models have been produced featuring a face plate which automatically self-darkens electronically. To protect bystanders, transparent welding curtains often surround the welding area. These curtains, made of a polyvinyl chloride plastic film, shield nearby workers from exposure to the UV light from the electric arc.\nInhaled matter.\nWelders are also often exposed to dangerous gases and particulate matter. Processes like flux-cored arc welding and shielded metal arc welding produce smoke containing particles of various types of oxides. The size of the particles in question tends to influence the toxicity of the fumes, with smaller particles presenting a greater danger. Additionally, many processes produce various gases (most commonly carbon dioxide and ozone, but others as well) that can prove dangerous if ventilation is inadequate.\nElectrical safety.\nWhile the open-circuit voltage of an arc welding machine may be only a few tens of volts up to about 120 volts, even these low voltages can present a hazard of electric shock for the operators. Locations such as ship's hulls, storage tanks, metal structural steel, or in wet areas are usually at earth ground potential and operators may be standing or resting on these surfaces during operating of the electric arc. Welding machines operating off AC power distribution systems must isolate the arc circuit from earth ground to prevent insulation faults in the machine from exposing operators to high voltage. The return clamp of the welding machine is located near to the work area, to reduce the risk of stray current traveling a long way to create heating hazards or electric shock exposure, or to cause damage to sensitive electronic devices. Welding operators are careful to install return clamps so that welding current cannot pass through the bearings of electric motors, conveyor rollers, or other rotating components, which would cause damage to bearings. Welding on electrical buswork connected to transformers presents a danger of the low welding voltage being \"stepped up\" to much higher voltages, so extra grounding cables may be required.\nInterference with pacemakers.\nCertain welding machines which use a high frequency alternating current component have been found to affect pacemaker operation when within 2 meters of the power unit and 1 meter of the weld site.\nHistory.\nWhile examples of forge welding go back to the Bronze Age and the Iron Age, arc welding did not come into practice until much later.\nIn 1800 Humphry Davy discovered the short pulsed electric arcs. Independently, a Russian physicist named Vasily Petrov discovered the continuous electric arc in 1802 and subsequently proposed its possible practical applications, including welding. Arc welding was first developed when Nikolai Benardos presented arc welding of metals using a carbon electrode at the International Exposition of Electricity, Paris in 1881, which was patented together with Stanisław Olszewski in 1887. In the same year, French electrical inventor Auguste de Méritens also invented a carbon arc welding method, patented in 1881, which was successfully used for welding lead in the manufacture of lead–acid batteries. The advances in arc welding continued with the invention of metal electrodes in the late 19th century by a Russian, Nikolai Slavyanov (1888), and an American, C. L. Coffin. Around 1900, A. P. Strohmenger released in Britain a coated metal electrode which gave a more stable arc. In 1905 Russian scientist Vladimir Mitkevich proposed the usage of three-phase electric arc for welding. In 1919, alternating current welding was invented by C. J. Holslag but did not become popular for another decade.\nCompeting welding processes such as resistance welding and oxyfuel welding were developed during this time as well; but both, especially the latter, faced stiff competition from arc welding especially after metal coverings (known as flux) for the electrode, to stabilize the arc and shield the base material from impurities, continued to be developed.\nDuring World War I welding started to be used in shipbuilding in Great Britain in place of riveted steel plates. The Americans also became more accepting of the new technology when the process allowed them to repair their ships quickly after a German attack in the New York Harbor at the beginning of the war. Arc welding was first applied to aircraft during the war as well, and some German airplane fuselages were constructed using this process. In 1919, the British shipbuilder Cammell Laird started construction of a merchant ship, the \"Fullagar\", with an entirely welded hull; she was launched in 1921.\nDuring the 1920s, major advances were made in welding technology, including the 1920 introduction of automatic welding in which electrode wire was continuously fed. Shielding gas became a subject receiving much attention as scientists attempted to protect welds from the effects of oxygen and nitrogen in the atmosphere. Porosity and brittleness were the primary problems and the solutions that developed included the use of hydrogen, argon, and helium as welding atmospheres. During the following decade, further advances allowed for the welding of reactive metals such as aluminum and magnesium. This, in conjunction with developments in automatic welding, alternating current, and fluxes fed a major expansion of arc welding during the 1930s and then during World War II.\nDuring the middle of the century, many new welding methods were invented. Submerged arc welding was invented in 1930 and continues to be popular today. In 1932 a Russian, Konstantin Khrenov successfully implemented the first underwater electric arc welding. Gas tungsten arc welding, after decades of development, was finally perfected in 1941 and gas metal arc welding followed in 1948, allowing for fast welding of non-ferrous materials but requiring expensive shielding gases. Using a consumable electrode and a carbon dioxide atmosphere as a shielding gas, it quickly became the most popular metal arc welding process. In 1957, the flux-cored arc welding process debuted in which the self-shielded wire electrode could be used with automatic equipment, resulting in greatly increased welding speeds. In that same year, plasma arc welding was invented. Electroslag welding was released in 1958 and was followed by its cousin, electrogas welding, in 1961.", "Engineering,_Manufacturing": 0.9999890327, "qwen": "Yes"}
{"id": "44380941", "revid": "45116746", "url": "https://en.wikipedia.org/wiki?curid=44380941", "title": "Product strategy", "text": "Product strategy defines the high-level plan for developing and marketing a product, how the product supports the business strategy and goals, and is brought to life through product roadmaps. A product strategy describes a vision of the future with this product, the ideal customer profile and market to serve, go-to-market and positioning (marketing), thematic areas of investment, and measures of success. A product strategy sets the direction for new product development. Companies utilize the product strategy in strategic planning and marketing to set the direction of the company's activities. The product strategy is composed of a variety of sequential processes in order for the vision to be effectively achieved. The strategy must be clear in terms of the target customer and market of the product in order to plan the roadmap needed to achieve strategic goals and give customers better value.\nGoals of product strategy.\nProduct strategy aims to provide context for what the product and business intends to achieve, the target customers and market, and the work to accomplish.\nVision provides the big picture of what the company is trying to achieve. Without vision, it will be difficult for stakeholders to understand its direction and it will lack connection to a broader picture. \nExecution is defined by the product roadmap. While the product strategy outlines the elements of the product and the company's target market, the product roadmap explains how the vision will be executed\nBig picture context provides the background of each feature and how it relates to larger goals. It also include details in which certain features will be built, and in what order.\nInitiatives are the high-level efforts that help achieve goals. For example, performance improvements and expansion of markets.\nExample.\nProduct differentiation occurs when companies have to distinguish a certain product in the marketplace when competing for a product that bring about the same need (e.g. tea) amongst different firms. In order to do so, the aim is to make the product more attractive to the marketplace compared to other competitors. This does not only include price, but also features of the product, quality, packaging, benefits and services. Successful product differentiation creates a comparative advantage for the firm.\nAs an example, a companies competitor in the market sells Tea A but they sell Tea B, so the company will then have to focus on producing Tea B so that consumers find their product to be more appealing (in terms of price, taste and services) compared to their competitors.\nProduct Life Cycle Concept.\nThe product life cycle concept consist of 4 stages: introduction, growth, maturity, obsolescence. It outlines the stages the product was first introduced into the market until it is finally removed from the market. The length of the life cycle, duration of each stage and the shape of the curve vary widely for different products. Not all products reach the final stage and some may continue to rise or even fall. \nObsolescence.\nTo extend a life of the product, techniques include advertising, price reduction (attract new customers), adding value to the product (new features), explore new markets (selling the product overseas) and new packaging (freshen up old packaging). \nProduct Platform Strategy.\nBeyond individual-product strategy is platform strategy, where the focus is on multiple products. There are two very different types of platforms: digital platforms in technology, and physical platforms in other fields.\nA digital platform is an ecosystem designed to enable different groups to co-create value through “plug-and-play” capabilities. The technology infrastructure of the platform touches customers and developers beyond the firm's boundaries. LinkedIn, Facebook, Google and Amazon—in fact most technology businesses—have platform-based business models. \nPhysical platforms in other industries refer to product family or product portfolio platforms intended to reduce manufacturing and development costs for new products. In this case a platform is a common architecture, collection of assets, component designs, subsystems, or other elements shared by several products. Given that the components and subsystems have already been debugged and tested, the resulting products should have higher quality. Since platform development occurs less frequently than product development, major platform decisions do not need to be made as often. This has the potential to foster lean product development. However, there are downsides: high upfront costs, risk of platform obsolescence, risk of platform recall affecting numerous products, and potential duplication of effort.", "Engineering,_Manufacturing": 0.9958259463, "qwen": "Yes"}
{"id": "44382811", "revid": "45599447", "url": "https://en.wikipedia.org/wiki?curid=44382811", "title": "Machine factory", "text": "A machine factory is a company, that produces machines. These companies traditionally belong to the heavy industry sector in comparison to a more consumer oriented and less capital intensive light industry. Today many companies make more sophisticated smaller machines, and they belong to the light industry. The economic sector of machine factories is called the machine industry.\nHistory.\nThe machinery factories came into existence in the course of the Industrial Revolution. Late 18th century most production machines, were still made of wood and manufactured in local workshops. The first industrial factories, such as cotton mills and cotton weavers, started their own workshops, where clockmakers, instrument makers, joiners and cabinet makers were employed to build and maintain the production machines. \nIn the first half of the 19th century gradually the wooden machinery got replaced by metal machine. The machine building gradually broke loose from the textile industry and independent companies emerged specializing in textile machinery, machine tools, locomotives, large steam engines, etc. Most companies in countries as England, France and Germany kept making their own special tools and machines. Lintsen recalled that \"only shortly before 1850, there is clear evidence of success in the effort to build 'machines with machines'. A number of so-called machine tools - lathes, planers, drills, cutters - gained the degree of accuracy needed to produce larger series of interchangeable parts. But even these standardization of parts did not mean the end of the individual craftsmanship in the machine industry.\"\nThe first machine tools offered for sale (i.e., commercially available) were constructed by Matthew Murray in England around 1800. Others, such as Henry Maudslay, James Nasmyth, and Joseph Whitworth, soon followed the path of expanding their entrepreneurship from manufactured end products and millwright work into the realm of building machine tools for sale. in the 1830s James Nasmyth had \"somewhat to his surprise... discovered, that there was really a market emerging for readymade lathes, planers, drills and flat banks. That demand partly originated from the people building the Lancashire textile machinery, and partly from the new phenomenon: the railways. The fast-growing rail network had locomotives, equipped repair shops, tracks and more demands.\" \nIn the second part of the 19th century more and more machine factories were started. These companies partly grew out of iron foundries, shipyards, forges and repair shops. Many production machines were sold to machine shops, where parts and consumer products were produced. Early 20th century several motorcycle and automobile manufacturers began their own machine factories. \nNowadays, many of the contemporary machine factories are smaller in size and belong to the light or medium metal. This type of companies generally produce specific production machines and /or devices, in which fine mechanics and electronics often plays a significantly role. Some of these types of companies have been around for decades, others are constantly created.\nTypes of machine factories.\nAgricultural machine factories.\nAgricultural machinery is machinery used in the operation of an agricultural area or farm. There is a range of machinery from tractor and to agricultural implements for soil cultivation, planting, fertilizing & pest control, irrigation, produce sorter, harvesting, hay making, loading and milking. These are produced by agricultural machinery manufacturers, and farming machines factories.\nEngine manufacturers.\nAn engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines (such as steam engines) burn a fuel to create heat, which then creates motion. Electric motors convert electrical energy into mechanical motion, pneumatic motors use compressed air and others—such as clockwork motors in wind-up toys—use elastic energy. In biological systems, molecular motors, like myosins in muscles, use chemical energy to create motion.\nHome appliance manufacturers.\nHome appliances are electrical/mechanical machines which accomplish some household functions, such as cooking or cleaning. \nThis division is noticeable in the maintenance and repair of these kinds of products. Brown goods usually require high technical knowledge and skills (which get more complex with time, such as going from a soldering iron to a hot-air soldering station), while white goods may need more practical skills and \"brute force\" to manipulate the devices and heavy tools required to repair them.\nSpecific machine factories in this field are sewing machine factory, and washing machine factory.\nIndustrial machine manufacturers.\nIndustrial machine manufacturers produce machine tools, production machines and other industrial equipment.\nMachine tool industry.\nA machine tool builder in the broadest sense is a corporation or person that builds machine tools. In the most common (and economically significant) sense of the term, a machine tool builder is a corporation whose business is building machine tools for sale to manufacturers, who use them to manufacture products. The machine tools often make interchangeable parts, which are assembled into subassemblies or finished assemblies, ending up sold to consumers, either directly or through other businesses at intermediate links of a value-adding chain. Alternatively, the machine tools may help make molds or dies, which then make the parts for the assemblies.", "Engineering,_Manufacturing": 1.0000082254, "qwen": "Yes"}
{"id": "31850317", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=31850317", "title": "Digital embossing", "text": "Digital embossing is a digital printing technology enhancement process. Digital embossing eliminates the need for printing plates, molds, chemicals, and solvents. The process emits no pollutants or waste and reduces energy use. The high resolution inkjet technology enables selective coating with variable thickness and stamp-less embossing. Digital embossing allows for on-demand printing of as few as one item in thousands of copies.\nDigital embossing was invented by Scodix, an Israel-based startup company that produces equipment for print enhancement applications in the commercial and packaging industries. Digital embossing enhancement technology was first unveiled at IPEX 2010 on the Scodix1200™ UV DigitalEmbossing™ press.\nDigital embossing can be specified by different print modes.\nPreparation.\nThe preparation for digital embossing requires an additional black separation from the image. The accuracy of the process (each sheet is registered optically before printing) enables embossing of complex shapes.\nProduction time.\nDigital embossing typically adds two minutes to printing production time.", "Engineering,_Manufacturing": 0.9999722242, "qwen": "Yes"}
{"id": "51118585", "revid": "21797031", "url": "https://en.wikipedia.org/wiki?curid=51118585", "title": "2016 Copa Sudamericana elimination stages", "text": "The 2016 Copa Sudamericana elimination stages were played from 9 August to 15 September 2016. A total of 46 teams competed in the elimination stages to decide 15 of the 16 places in the final stages of the 2016 Copa Sudamericana.\nDraw.\n\nThe draw of the tournament was held on 12 July 2016, 20:00 CLT , at the Espacio Riesco Convention and Events Center in Huechuraba, Chile.\nFor the first stage, the 32 teams were divided into two zones:\nTeams which qualified for berths 1 were drawn against teams which qualified for berths 4, and teams which qualified for berths 2 were drawn against teams which qualified for berths 3, with the former hosting the second leg in both cases. Teams from the same association could not be drawn into the same tie.\nFor the second stage, the 30 teams, including the 16 winners of the first stage (eight from South Zone, eight from North Zone), whose identity was not known at the time of the draw, and the 14 teams which entered the second stage, were divided into three sections:\nFormat.\n\nIn the elimination stages (first stage and second stage), each tie was played on a home-and-away two-legged basis. If tied on aggregate, the away goals rule would be used. If still tied, extra time would not be played, and the penalty shoot-out would be used to determine the winner (Regulations Article 5.1). The 15 winners of the second stage (eight from winners of the first stage, four from Brazil, three from Argentina) advanced to the round of 16 to join the defending champions (Santa Fe).\nFirst stage.\nThe first legs were played on 9–11 August, and the second legs were played on 16–18 August 2016.\n\n!colspan=6|South Zone\n!colspan=6|North Zone\nMatch G1.\n\"Cerro Porteño won 2–1 on aggregate and advanced to the second stage (Match O8).\"\nMatch G2.\n\"Tied 1–1 on aggregate, Sportivo Luqueño won on away goals and advanced to the second stage (Match O16).\"\nMatch G3.\n\"Bolívar won 3–2 on aggregate and advanced to the second stage (Match O4).\"\nMatch G4.\n\"Real Potosí won 4–2 on aggregate and advanced to the second stage (Match O8).\"\nMatch G5.\n\"Tied 1–1 on aggregate, Blooming won on penalties and advanced to the second stage (Match O6).\"\nMatch G6.\n\"Tied 2–2 on aggregate, Sol de América won on penalties and advanced to the second stage (Match O13).\"\nMatch G7.\n\"Tied 0–0 on aggregate, Montevideo Wanderers won on penalties and advanced to the second stage (Match O11).\"\nMatch G8.\n\"Palestino won 4–0 on aggregate and advanced to the second stage (Match O10).\"\nMatch G9.\n\"Emelec won 6–1 on aggregate and advanced to the second stage (Match O2).\"\nMatch G10.\n\"Tied 2–2 on aggregate, Real Garcilaso won on away goals and advanced to the second stage (Match O10).\"\nMatch G11.\n\"Junior won 5–2 on aggregate and advanced to the second stage (Match O6).\"\nMatch G12.\n\"Deportivo La Guaira won 1–0 on aggregate and advanced to the second stage (Match O2).\"\nMatch G13.\n\"Tied 2–2 on aggregate, Zamora won on penalties and advanced to the second stage (Match O11).\"\nMatch G14.\n\"Independiente Medellín won 2–1 on aggregate and advanced to the second stage (Match O16).\"\nMatch G15.\n\"Tied 2–2 on aggregate, Sport Huancayo won on away goals and advanced to the second stage (Match O13).\"\nMatch G16.\n\"Atlético Nacional won 6–0 on aggregate and advanced to the second stage (Match O4).\"\nSecond stage.\nThe first legs were played on 23–25 August, and the second legs were played on 31 August and 13–15 September 2016.\n\nMatch O1.\n\"Santa Cruz won 1–0 on aggregate and advanced to the round of 16 (Match A).\"\nMatch O2.\n\"Deportivo La Guaira won 4–2 on aggregate and advanced to the round of 16 (Match B).\"\nMatch O3.\n\"Chapecoense won 3–2 on aggregate and advanced to the round of 16 (Match C).\"\nMatch O4.\n\"Atlético Nacional won 2–1 on aggregate and advanced to the round of 16 (Match D).\"\nMatch O5.\n\"Belgrano won 2–1 on aggregate and advanced to the round of 16 (Match E).\"\nMatch O6.\n\"Junior won 3–1 on aggregate and advanced to the round of 16 (Match F).\"\nMatch O7.\n\"Tied 5–5 on aggregate, Flamengo won on away goals and advanced to the round of 16 (Match G).\"\nMatch O8.\n\"Cerro Porteño won 7–0 on aggregate and advanced to the round of 16 (Match H).\"\nMatch O10.\n\"Palestino won 3–2 on aggregate and advanced to the round of 16 (Match G).\"\nMatch O11.\n\"Montevideo Wanderers won 2–0 on aggregate and advanced to the round of 16 (Match F).\"\nMatch O12.\n\"Tied 2–2 on aggregate, Coritiba won on away goals and advanced to the round of 16 (Match E).\"\nMatch O13.\n\"Sol de América won 2–1 on aggregate and advanced to the round of 16 (Match D).\"\nMatch O14.\n\"Independiente won 3–0 on aggregate and advanced to the round of 16 (Match C).\"\nMatch O15.\n\"San Lorenzo won 4–3 on aggregate and advanced to the round of 16 (Match B).\"\nMatch O16.\n\"Independiente Medellín won 3–2 on aggregate and advanced to the round of 16 (Match A).\"", "Engineering,_Manufacturing": 0.9886142015, "qwen": "Yes"}
{"id": "12305335", "revid": "507787", "url": "https://en.wikipedia.org/wiki?curid=12305335", "title": "Steel casting", "text": "Steel casting is a specialized form of casting involving various types of steel cast to either final/net or near-net shape. Steel castings are used when iron castings cannot deliver enough strength or shock resistance.\nExamples of items that are steel castings include: hydroelectric turbine wheels, forging presses, gears, railroad truck frames, valve bodies, pump casings, mining machinery, marine equipment, turbocharger turbines and engine cylinder blocks.\nSteel castings are categorized into two general groups: carbon steels and alloy steels.\nSteel castability.\nSteel is more difficult to cast than iron. It has a higher melting point and greater shrinkage rate, which requires consideration during mold design. Risers should be given more capacity to draw from as the metal cools and shrinks. Attention should be paid to the thickness of mold cavities, as thinner areas will cool quicker than thicker areas, which can create internal stress points that can lead to fracture. \nMolten steel is also less fluid than molten iron, making it more difficult to pour and fill intricate gaps in a mold cavity. Molten steel is also more likely to react with internal mold surfaces, making for more unpredictable results.\nMachinability.\nCast parts often require machining to achieve accurate tolerances and desired surface finishes. Carbon steel is the easiest type of steel to machine. High-carbon steel can be more time consuming to cut or grind, and will wear tools faster. Low-carbon steel can get gummy, making it difficult to work with. \nGenerally, the presence of alloys used to increase mechanical performance often make machining more difficult. \nDamping ability.\nCasting is often a valuable means to creating intricate parts used in machine applications where vibration is often a factor. Cast steel typically has a lower damping ability than cast iron, which can lead to excess vibration and noise in the form of ringing or squealing.\nImpact and wear resistance.\nMost steels offer a good balance of strength and ductility, which makes them extremely tough. This allows them to withstand significant stress and strain without fracturing. Steel can also be fairly wear-resistant. Alloy additions can increase both impact and wear resistance.\nSteel casting alloys.\nAlloy steel castings are broken down into two categories: low-alloy steels and high-alloy steels. Low-alloy steels contain less than 8% alloying content and high-alloy steels have 8% or more.\nThis is a table of some steel casting alloys:\nTerminology.\nIn present-day vocabulary, the term \"cast steel\" is almost always used in its sense referring to steel castings. Between the late 19th and mid 20th centuries, this was not always true, which is worth understanding if one is reading historical documents; see \"cast steel\" for details. ", "Engineering,_Manufacturing": 0.9996629953, "qwen": "Yes"}
{"id": "12319360", "revid": "9895903", "url": "https://en.wikipedia.org/wiki?curid=12319360", "title": "Ticket punch", "text": "A ticket punch (or control nippers) is a hand tool for permanently marking admission tickets and similar items of paper or card stock. It makes a perforation and a corresponding chad. A ticket punch resembles a hole punch, differing in that the ticket punch has a longer jaw (or \"reach\") and the option of having a distinctive die shape. A ticket punch resembles a needle punch in that it makes a distinctive pattern in the item punched, but differs in that it makes a chad.\nUses.\nTicket punches are widely used to mark railway passenger tickets, particularly if it is important when and where the ticket was punched. Ticket punches were also widely used in orienteering but have been replaced by needle punches (see control point in Orienteering).\nTicket punches also have decorative uses, involving both their perforations and their chads. Available die shapes include many geometric shapes, silhouettes of objects or animals. Die shapes for company logos and other proprietary images can be manufactured by special arrangement. These are used to punch decorative holes in the margins of pieces of paper, and to make small confetti.\nPunched tickets were issued in BEST buses in Mumbai till 2011, when they were replaced with electronic ticketing systems. The older tickets have been reportedly used in artwork as well as in games.", "Engineering,_Manufacturing": 0.9951004982, "qwen": "Yes"}
{"id": "11172408", "revid": "45708962", "url": "https://en.wikipedia.org/wiki?curid=11172408", "title": "Thermographic printing", "text": "Thermographic printing refers to two types of printing, both of which rely on heat to create the letters or images on a sheet of paper. \nThe simplest type of thermography is where the paper has been coated with a material that changes colour on heating. This is called thermal printing and was used in older model fax machines and is used in most shop till receipt printers. This is called direct thermal.\nMore complex is thermal transfer printing that melts print off a ribbon and onto the sheet of paper.\nThermography as raised print process.\nThermography is also the name of a post print process that is achieved today using traditional printing methods coupled with thermography machines. Thermography machines consist of three sections with a through conveyor.\nThe first section applies thermographic/embossing powder, made from plastic resins, to the substrate (normally paper). The areas selected for raised printing are printed with slow-drying inks that do not contain dryers or hardeners so that they remain wet during the application of powder. This ink is dried and hardened later during the heating process.\nThe second section of the process is a vacuum system that removes excess powder from areas of the sheet that were not printed.\nThe third section of the process conveys the product through a radiant oven where it is exposed to temperatures of 900 to 1300ºF (500-700ºC). The heating process takes on the order of 2.5 to 3 seconds. The substrate (usually paper) has a peak in IR absorption at the wavelength used. Through conduction from the paper, the powder temperature rapidly increases and starts melting. When the process is correctly adjusted, the center of the largest filmed areas reach sufficient quality level as the product exits the heater. The melted ink then solidifies as the product cools.\nThis process is sometimes produced using manual powdering. The substrate with the wet ink is dipped into the powdered polymer. The sheet is then tilted back and forth, rolling the powder across the image. The excess powder is then removed by raising the substrate to a vertical position and lightly tapping the back side. The powdered sheet is then fed into a radiant heating system (as above) at a speed that achieves a good-quality melted film. In the case of craft applications, the powder is melted using a heatgun that blows hot air.\nIt is commonly used on wedding invitations, letterheads, business cards, greeting cards, gift wrap, packaging, etc. It is sometimes used in diploma printing as a low-cost alternative to engraved embossing.", "Engineering,_Manufacturing": 0.9999951124, "qwen": "Yes"}
{"id": "11172872", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=11172872", "title": "Linear stage", "text": "A linear stage or translation stage is a component of a precise motion system used to restrict an object to a single axis of motion. The term linear slide is often used interchangeably with \"linear stage\", though technically \"linear slide\" refers to a linear motion bearing, which is only a component of a linear stage. All linear stages consist of a platform and a base, joined by some form of guide or linear bearing in such a way that the platform is restricted to linear motion with respect to the base. In common usage, the term linear stage may or may not also include the mechanism by which the position of the platform is controlled relative to the base.\nPrinciple of operation.\nIn three-dimensional space, an object may either rotate about, or translate along any of three axes. Thus the object is said to have six degrees of freedom (3 rotational and 3 translational). A linear stage exhibits only one degree of freedom (translation along one axis). In other words, linear stages operate by physically restricting 3 axes of rotation and 2 axes of translation thus allowing for motion on only one translational axis.\nGuide types.\nLinear stages consist of a platform that moves relative to a base. The platform and base are joined by some form of guide which restricts motion of the platform to only one dimension. A variety of different styles of guides are used, each with benefits and drawbacks making each guide type more appropriate for some applications than for others.\nPosition control methods.\nThe position of the moving platform relative to the fixed base is typically controlled by a linear actuator of some form, whether manual, motorized, or hydraulic/pneumatic. The most common method is to incorporate a lead screw passing through a lead nut in the platform. The rotation of such a lead screw may be controlled either manually or by a motor.\nManual.\nIn manual linear stages, a control knob attached to a lead screw is typically used. The knob may be indexed to indicate its angular position. The linear displacement of the stage is related to the angular displacement of the knob by the lead screw pitch. For example if the lead screw pitch is 0.5 mm then one full revolution of the knob will move the stage platform 0.5 mm relative to the stage base. If the knob has 50 index marks around its circumference, then each index division is equivalent to 0.01 mm of linear motion of the stage platform.\nPrecision stages such as those used for optics do not use a lead screw, but instead use a fine-pitch screw or a micrometer which presses on a hardened metal pad on the stage platform. Rotating the screw or micrometer pushes the platform forward. A spring provides restoring force to keep the platform in contact with the actuator. This provides more precise motion of the stage. Stages designed to be mounted vertically use a slightly different arrangement, where the actuator is attached to the movable platform and its tip rests on a metal pad on the fixed base. This allows the weight of the platform and its load to be supported by the actuator rather than the spring.\nStepper motor.\nIn some automated stages a stepper motor may be used in place of, or in addition to a manual knob. A stepper motor moves in fixed increments called steps. In this sense it behaves very much like an indexed knob. If the lead screw pitch is 0.5 mm and the stepper motor has 200 steps per revolution (as is common), then each revolution of the motor will result in 0.5 mm of linear motion of the stage platform, and each step will result in 0.0025 mm of linear motion.\nDC motor with encoder.\nIn other automated stages a DC motor may be used in place of a manual control knob. A DC motor does not move in fixed increments. Therefore an alternate means is required to determine stage position. A scale may be attached to the internals of the stage and an encoder used to measure the position of the stage relative to the scale and report this to the motor controller, allowing a motion controller to reliably and repeatably move the stage to set positions.\nMultiple axis stage configurations.\nFor position control in more than one direction, multiple linear stages may be used together. A \"two-axis\" or \"X-Y\" stage can be assembled from two linear stages, one mounted to the platform of the other such that the axis of motion of the second stage is perpendicular to that of the first. A two-axis stage with which many people are familiar is a microscope stage, used to position a slide under a lens. A \"three-axis\" or \"X-Y-Z\" stage is composed of three linear stages mounted to each other (often with the use of an additional angle bracket) such that the axes of motion of all stages are orthogonal. Some two-axis and three-axis stages are integrated designs rather than being assembled from separate single-axis stages. Some multiple-axis stages also include rotary or tilt elements such as rotary stages or positioning goniometers. By combining linear and rotary elements in various ways, four-axis, five-axis, and six-axis stages are also possible. Linear stages take an advanced form of high performance positioning systems in applications which require a combination of high speed, high precision and high force.\nApplication.\nSemiconductor manufacturing.\nLinear stages are used in semiconductor devices fabrication process for precise linear positioning of wafers of the purposes of wafer mapping dielectric, characterization, and epitaxial layer monitoring where positioning speed and precision are critical.", "Engineering,_Manufacturing": 0.9983564615, "qwen": "Yes"}
{"id": "11172915", "revid": "252195", "url": "https://en.wikipedia.org/wiki?curid=11172915", "title": "Rotary stage", "text": "A rotary stage is a component of a motion system used to restrict an object to a single axis of rotation. The terms rotary table or rotation stage are often used interchangeably with rotary stage. All rotary stages consist of a platform and a base, joined by some form of guide in such a way that the platform is restricted to rotation about a single axis with respect to the base. In common usage, the term rotary stage may or may not also include the mechanism by which the angular position of the platform is controlled relative to the base.\nPrinciple of operation.\nIn three-dimensional space, an object may either rotate about, or translate along, any of three axes. Thus, the object is said to have six degrees of freedom (3 rotational and 3 translational). A rotary stage exhibits only one degree of freedom (rotation about one axis). In other words, rotary stages operate by physically restricting 3 axes of translation and 2 axes of rotation.\nBearing types.\nRotary stages consist of a platform that moves relative to a base. The platform and base are joined by some form of bearing which restricts motion of the platform to rotation about a single axis. A variety of different styles of bearings are used, each with benefits and drawbacks, making them more appropriate for some applications than for others.\nPlain bearing.\nA plain bearing is simply two surfaces sliding against each other. Typically, a circular step on the platform mates snugly with a circular depression in the base allowing free rotation while minimizing side to side motion. A rotary stage built with this type of bearing is usually only used for coarse positioning and is adjusted manually simply by turning the platform. Index marks on either the base or the platform are often provided, allowing for somewhat repeatable positioning of the platform relative to the base.\nRolling-element bearing.\nThis type of rotary stage includes ball bearing stages, crossed roller bearing stages, and possibly others. Any of a number of different rolling-element bearings may be employed. Typically, a pair of bearings is used and they are preloaded to take up any slack which could result in the stage platform lifting relative to the base.\nPosition control methods.\nManual direct.\nSome rotary stages are operated simply by turning the platform by hand. The platform may have index marks for setting different angular positions relative to the base. A locking mechanism may be provided to fix the platform to the base at the desired position.\nManual worm drive.\nFor more precise position control, a worm drive may be used. A worm wheel is fixed to the rotating platform and meshes with a worm in the base. Rotation of the worm via a manual control knob causes the platform to rotate with respect to the base. Index marks on both the control knob and the platform can be used to locate the platform very precisely and repeatably with respect to the base.\nStepper motor with worm drive.\nReplacing the manual control knob in the above manual worm drive scenario a stepper motor allows positioning of the rotary stage to be automated. A stepper motor rotates in fixed increments or steps. The number of steps moved is controlled by the stepper motor controller. In this sense, the stepper motor behaves much like an indexed control knob.\nDC motor and encoder with worm drive.\nA DC motor may also be used in place of a manual control knob. A DC motor does not move in fixed increments. Therefore, an alternate means is required to determine stage position. An encoder may be attached to the DC motor and used to report the angular position of the motor to the motor controller, allowing a motion controller to reliably and repeatably move the stage to set positions.\nLinear actuator.\nWhen precise angular positioning over only a small total angle is required, a linear actuator (either manual, or motorized) may be used. Typically, the range of motion possible is only 10° to 20° of rotation. The linear actuator presses against a contact surface fixed to the stage platform such that extension or retraction of the actuator causes the platform to rotate. The stage platform is sprung against the actuator tip so that the contact surface stays in contact with the actuator tip when the actuator retracts.", "Engineering,_Manufacturing": 1.0000048876, "qwen": "Yes"}
{"id": "605211", "revid": "10356121", "url": "https://en.wikipedia.org/wiki?curid=605211", "title": "Molding (process)", "text": "Molding (American English) or moulding (British and Commonwealth English; see spelling differences) is the process of manufacturing by shaping liquid or pliable raw material using a rigid frame called a mold or matrix. This itself may have been made using a pattern or model of the final object.\nA mold or mould is a hollowed-out block that is filled with a liquid or pliable material such as plastic, glass, metal, or ceramic raw material. The liquid hardens or sets inside the mold, adopting its shape. A mold is a counterpart to a cast. The very common bi-valve molding process uses two molds, one for each half of the object.\nArticulated molds have multiple pieces that come together to form the complete mold, and then disassemble to release the finished casting; they are expensive, but necessary when the casting shape has complex overhangs.\nPiece-molding uses a number of different molds, each creating a section of a complicated object. This is generally only used for larger and more valuable objects.\nBlow molding is a manufacturing process for forming and joining hollow plastic or glass parts.\nA manufacturer who makes molds is called a moldmaker. A release agent is typically used to make removal of the hardened/set substance from the mold more easily effected. Typical uses for molded plastics include molded furniture, molded household goods, molded cases, and structural materials. \nTypes.\nThere are several types of molding methods.\nThese includes:", "Engineering,_Manufacturing": 0.9999411106, "qwen": "Yes"}
{"id": "69632903", "revid": "1461430", "url": "https://en.wikipedia.org/wiki?curid=69632903", "title": "3D concrete printing", "text": "3D concrete printing, or simply concrete printing, refers to digital fabrication processes for cementitious materials based on one of several different 3D printing technologies. 3D printed concrete eliminates the need for formwork, reducing material waste and allowing for greater geometric freedom in complex structures. With recent developments in mix design and 3D printing technology over the last decade, 3D concrete printing has grown exponentially since its emergence in the 1990s. Architectural and structural applications of 3D-printed concrete include the production of building blocks, building modules, street furniture, pedestrian bridges, and low-rise residential structures.\nHistory.\nAutomating building processes has been an area of research in architecture and civil engineering since the 20th century. The earliest approaches focused on automating masonry. In 1904, a patent for a brick-laying machine was granted to John Thomas in the US. By the 1960s, the technology developed significantly and functional equipment, such as the Motor-Mason, were in use on building sites.\nAt the same time, automating concrete construction processes was also being developed. Slip forming, a widely used technique today for building vertical concrete cores for high-rise buildings, was developed in the early 20th century for building silos and grain elevators. The concept was pioneered by James MacDonald, of MacDonald Engineering Chicago, and published by Milko S. Ketchum in an illustrated book: \"The Design of Walls, Bins, and Grain Elevators\" in 1907. Later, MacDonald published a scientific paper: \"Moving Forms for Reinforced Concrete Storage Bins\" in 1911. Finally, on 24 May 1917, MacDonald was granted a US patent for a device to move and elevate a concrete form in a vertical plane.\nInnovations in the automation of concreting processes continued throughout the 20th century. 3D printing processes were first developed in the 1980s for photopolymers and thermoplastics. For some time, 3D printing technology was limited to high value adding sectors such as aerospace and biomedical industries due to the high cost of materials. However, as the knowledge base for 3D printing grew, new additive manufacturing processes were developed for other materials, including for concrete. 3D printed concrete technology originated from Rensselaer Polytechnic Institute (RPI) in New York when Joseph Pegna first applied additive manufacturing to concrete in 1997. This experiment was just a proof of concept, but Pegna recognized the developing robotics industry and saw it as an opportunity to automate the construction process, while also decreasing costs and waste production. Pegna's research would later become the basis for binder jetting, or powder based 3D concrete printing.\nIn 1998, Behrohk Khoshnevis at the University of Southern California developed Contour Crafting, which was the first layered extrusion device for concrete. The system used a computer controlled crane to automate the pouring process and was capable of creating smooth contour surfaces. Khoshnevis initially designed this system to serve as rapid home construction for natural disaster recovery, and he claimed that the system could complete a home in a single day. With innovations in materials, mix design, and printing technology, researchers and engineers have since expanded on these two printing techniques, which will be discussed further in the following section.\nConstruction methods.\nA number of different approaches have been demonstrated to date, which include on-site and off-site fabrication of building elements or entire buildings, using industrial robots, systems, and tethered autonomous vehicles (see section on 3D Printers). Demonstrations of construction 3D printing technologies have included fabrication of housing, building elements (cladding, structural panels, and columns), bridges, civil infrastructure, artificial reefs, follies, and sculptures. Three different construction methods are currently used in 3D concrete printing: binder jetting, robotic shotcrete, and layered material extrusion.\nBinder jetting.\nBinder jet 3D printing, also known as powder bed and binder 3D printing, was originally developed at the Massachusetts Institute of Technology for activating starch or gypsum powder with water as binder, before Joseph Pegna applied the system to concrete. In binder jetting, a print head selectively deposits a liquid binder on a powdered substrate, layer by layer. The layer height typically varies between 0.2 and 2 mm and determines both the speed and the level of detail in the finished part. Post-processing steps are necessary in binder-jetting once the layered fabrication is complete. First, the unconsolidated powder needs to be removed mechanically, using brushes and vacuum tubes. Additional curing steps may also be necessary in ovens with controlled humidity and temperature or micro-waves. Finally, coatings may also be applied on the surface to consolidate small surface features or to improve the surface quality of the part. Typical materials used for coatings are polyester or epoxy resin.\n3D concrete printing with binder jetting technologies has been demonstrated at large scale by Enrico Dini with D-Shape. D-Shape relies on a non-hydraulic Sorel cement that is based on sand activated with magnesium oxide in the powder bed and a liquid magnesium chloride solution as binder. The technology has mainly been used to create furniture, such as a coffee table and the Root Chair designed by KOL/MAC LLC Architecture + Design in 2009. Furthermore, D-Shape produced large architectural parts, such as the 3 × 3 × 3 m Radiolaria pavilion designed by Shiro Studio in 2008, the Ferreri House for the Triennale di Milano in 2010, and a twelve-metre-long footbridge designed by Acciona in Madrid, in 2017.\nAnother exponent of binder-jet 3D concrete printing is California-based firm Emerging Objects. For their Bloom pavilion built in 2015, the company used an iron oxide-free cement and organic binder. While it is unclear if there is any cement hydration involved in the process, the project is often cited among other binder-jet 3D concrete printing projects due to the use of cement in the powder bed. Unlike the structures of D-Shape, which were fabricated in one piece, Emerging Objects fabricated 840 small building blocks that were stacked to create the 3.6 × 3.6 × 2.7 m structure.\nAdvantages and limitations.\nCompared to other 3D printing methods for architectural applications, binder jetting allows for a higher degree of geometric freedom, including the possibility to create unsupported cantilevers or overhangs and hollow parts. Unlike other 3D printing processes that require auxiliary support structures, binder jetting relies on the bed of unbonded powder to ensure continuous support for consecutive layers during fabrication.\nTypically, in binder jet 3D printing, the left-over powder can be reused for future parts. However, the recyclability of the cement and aggregate powder is problematic due to the exposure to ambient humidity, which can trigger the hydration process. Therefore, binder jet 3D printing is not suitable for on-site construction.\nLayered extrusion 3D printing.\nConcrete layered extrusion 3D printing involves a numerically controlled nozzle that precisely extrudes a cementitious paste layer by layer. Layers are generally between 5 mm and a few centimeters in thickness. The extrusion nozzle may be accompanied by an automatic troweling tool that flattens the 3D-printed layers and covers the grooves at the interlayer interfaces, resulting in a smooth concrete surface. Additional automation steps have been proposed for the integration in one fabrication step of modular steel reinforcement bars or integrated building services, such as plumbing or electrical conduits. For this process, process planning and deposition speed are critical parameters that influence the material's stiffening and hardening rate.\nLayered extrusion 3D concrete printing is most commonly used in on-site construction, and is accompanied by large scale 3D printers (see section on 3D Printers). The technology has seen a growing interest recently, with numerous universities, start-ups, and prominent established construction companies developing dedicated hardware, concrete mixes, and automation setups for concrete extrusion 3D printing. Applications include bridges, columns, walls, floor slabs, street furniture, water tanks, and entire buildings, both in prefabrication or in-situ setups.\nAdvantages and limitations.\nUnlike conventional concrete casting and spraying, layered extrusion 3D printing needs no formworks. This is a significant advantage considering the fact that formworks in concrete construction can account for 50-80% of the resources, more than raw materials, reinforcement, and labour combined. The main challenges of layered concrete extrusion are the set on demand rheology of concrete, the integration of reinforcement, and the formation of cold joints at the interface between consecutive layers.\nSlip forming.\nRobotic slip-forming, a process developed at ETH Zürich under the name Smart Dynamic Casting, is sometimes included in the family of concrete 3D printing processes, together with layered extrusion and binder-jetting. The process loosely fits the definition of 3D printing, due to its additive nature, material being slowly extruded through an actuated mould that can vary its section. However, unlike the other 3D printing processes, slip forming is a continuous process, and not discrete or layer-based, and therefore it is more closely related to formative processes such as casting and extrusion.\nTechnology.\n3D Printers for Concrete.\nThere are a few main categories of robots that are used for 3D concrete printing, which depends on the application, scale of the project, and printing technique. All construction 3D printers generally consist of a support structure and a printer head with a nozzle that extrudes the concrete. Printers are usually used in tandem with modelling software that uploads the building plans directly to the printer. \nPrinter Parameters.\nIn addition to printer type, specific printer parameters significantly impact the final performance of 3D printed concrete and must be carefully selected when planning for 3D printing construction. These parameters can simply be broken down into print head design and print speed.\nPrint Head Design.\nThe print head must be selected so that the concrete mix can smoothly pass through the nozzle and create the bonding effect between each layer, while also initiating the solidification process. Similar to printer selection, nozzle shapes and sizes vary depending on the application. 3D printed concrete samples from nozzles with rectangular holes typically have higher strength than those printed with circular nozzles, because there are fewer gaps between each printed layer. However, circular nozzles are more adept for printing complex geometries. For samples printed from the same nozzle type, mechanical properties are improved when a larger nozzle is used.\nThe height of the print head is the height of the nozzle relative to the printing platform. This parameter affects the surface quality between layers including bond strength, and must be precisely adjusted. A print head that is set too high will reduce the bond strength between layers, causing an unstable shape. A nozzle too close to the printing surface may interfere with the printing process and place additional loads on the concrete. Research proposes a print height equal to the width of the nozzle.\nPrint Speed.\nThe speed at which the print head is set also influences the bonding strength. Increasing the nozzle speed generally decreases the adhesive strength, as the concrete has little time to set into place. However, taking too long to print successive layers reduces interlayer bonding, so a balance must be established that accounts for strength without premature collapse. Other factors that influence the quality of 3D printed concrete include the pumps and controls used to monitor the printer, as well the concrete mix design (See section on Mix Design).\n3D Printer Suppliers.\n3D concrete printing technology has grown exponentially over the last decade, and is expected to continue to grow as researchers learn more about the software, hardware, and construction capabilities of these printers. Below are some notable companies and 3D printers that are used globally: \nMix Design.\nCritical Mix Properties.\nFor 3D printed concrete, buildability and extrudability are two of the most critical design properties for a mix. Extrudability is the mixture's ability to pass through nozzles in the printing head, while buildability is the capacity to support additional layers. These properties are governed by the consistency, cohesiveness, and stability of the mixture, which stem from the mix design and selected materials. For both properties, a balance must be met between stiffness and workability. A stiff mix will increase strength, but decrease flow rate and print speed, potentially clogging the printer head. Conversely, decreasing the stiffness too much may increase workability and extrudability at the expense of strength and buildability.\nSince concrete is printed in layers, layers must sufficiently bond to each other to allow for proper curing and full-strength capacity. Significant research has been conducted to create an optimal mix for 3D printing, although there are no current industry standards. However, the use of supplementary cementitious materials (SCMs) such as metakaolin, fly ash, silica fume, and superplasticizers are common in all 3D printed concrete mixtures (See section on Admixtures).\nCementitious Materials.\nCementitious materials are integral to any concrete mix design. These materials serve as the binder that holds the mix together, as they chemically react with water to undergo the curing process. Portland cement is the most common material in construction for both 3D printed and traditional concrete applications due to its low cost and widespread availability. However, it's high setting time and low bonding ability are disadvantageous for 3D printed applications. Therefore, polymers and other admixtures are often added to reduce shrinkage and improve adhesion. Some of these polymers include rubber, mixed sand aggregates, carbon-sulfur polymers, and geopolymers, which also have added benefits of crack repair and resistance.\nOne alternative is sulfoaluminate cement which can be mixed with Portland Cement to quicken the hydration process and help develop early concrete strength after placement. While the setting time of Portland Cement is about half an hour, the setting time for sulfoaluminate cement is just six minutes. Therefore, higher strength can be achieved in a much shorter time period, increasing buildability.\nAggregates.\nAggregate content and selection are just as important as the selected cementitious materials when it comes to concrete mix design. In particular, particle size has a significant effect on 3D printed concrete mixes. Particle sizes that are too large may block the nozzle of the 3D printer, while aggregates that are too small decrease the strength of the mix and can cause cracking. A rule of thumb for mix design is that the maximum aggregate particle size should be less than 1/10 of the nozzle diameter to ensure smooth extrusion.\nSeveral studies have been conducted to examine the influence of aggregate size on mechanical properties for 3D printed concrete. It was found that increasing coarse aggregate improves volumetric stability of concrete and decreases hydration heat and shrinkage, which were common problems in early 3D printed concrete mixes. The use of coarse aggregate also increases concrete deposition rate and printhead speed, which can increase printing efficiency and productivity. Therefore, the printed structure achieves greater stability and strength, as observed by Ivanova and Mechtcherine. There is a limit to coarse aggregate content and size, as the challenge of controlling rheology become apparent. Natural aggregates such as sand and gravel are preferred as they require less energy to produce compared to artificial aggregates, but aggregate selection can be limited by regional deposits.\nAdmixtures.\nAdmixtures include any materials outside of water, aggregates, and cementitious materials, that affect the concrete mix properties. Especially in 3D printed concrete, these admixtures are critical to balancing buildability, workability, and extrudability. Fly ash is the main admixture for high performance 3D printed concrete, as it improves working performance and durability. However, large amounts of flyash can lead to slower development of strength and buildability, which is why it is often mixed with other admixtures like clay, to retain shape stability.\nSilica fume is another common admixture for 3D printed concrete mixes, as it increases the initial strength of printed concrete as well as flexural strength once the concrete cures. The main advantage of silica fume is that its small particles fill in the void spaces around the larger aggregates, which improves bonding performance with the cement binder. This also helps optimize the particle size distribution of the mix, which increases yield stress and buildability.\nMechanical Properties.\nAs with standard concrete mixes, mixes for 3D printed concrete are typically tested for their compressive and flexural strength. These mechanical properties are highly dependent on the mix design, and can be improved by adding admixtures such as the ones described in the above section. For a mix containing ordinary Portland Cement, fly ash, silica fume, and fine glass aggregates, the compressive strength is around 36 to 57 MPa, which is comparable to the compressive strength of normal weight concrete. High performance concrete strengths of over 100 MPa have also been achieved by using superplasticizers and additional chemicals, but these mixes are more energy intensive to produce.\nFor 3D printed concrete, the structural properties are largely influenced by the interlayer bonding performance. Increasing the print speed and printhead height can reduce the interlayer bond strength, while adding a mortar between the layers can improve this strength. Particular, a resin mortar composed of black charcoal, sulfur, and sand has been found to be effective.\nConcrete Suppliers for 3D Printing.\nSince there are no standards set for 3D printing concrete mix design, companies often pursue their own research and development if they decide to offer 3D printing as a construction service. Below are some notable companies that have successfully implemented 3D concrete printing into their scope of services. \nNotable Projects and Applications.\nDue to challenges of reinforcement and limitations in printing technology, applications of 3D printed concrete have been mostly limited to small scale projects, including models and residential homes, as opposed to large commercial buildings. There are, however, some notable projects around the world that demonstrate the potential of 3D printed concrete.\nICON: 3D Printed Homes.\nICON is creating a community of 100 3D printed homes in Georgetown, Texas. Reservations will begin in 2023 with starting prices in the mid $400,000. The fleet of Vulcan printers can produce eight different floor plans of 3 to 4 bedrooms and 2 to 3 baths. A concrete feeding system known as Magma supplies the Vulcan printer with Icon's developed concrete mix known as Lavacrete, which can adjust for site weather conditions and supply read-to-print concrete automatically. The 90 to 200m2 3D printed homes take around five to seven days to print, compared to a timber frame which would take up to 16 weeks in the same area.\nICON also completed a project in March 2020 for seven 3D printed homes in Austin, Texas. Each 400 ft2 home was printed in just 27 hours using ICON's Vulcan printer. The first residents moved into the homes in 2020 and are estimated to house 480 of the city's homeless, about 40% of the city's homeless population.\nHabitat for Humanity: Affordable Homes Fast.\nIn 2021, Habitat for Humanity, the world's largest non-profit home builder organization, built two 3D printed homes in Williamsburg, Virginia, and Tempe, Arizona. The Virginia home was 1,200 ft2 and printed in just 28 hours with a COBOD 3D printer, which was about four weeks faster than standard construction. The organization estimated that the 3D printed concrete walls saved about 15% per square foot in building costs. The 1,738 ft2 home in Arizona was constructed in the summer: a time where construction typically halts due to the extreme heat. 80% of the home was constructed using 3D printing including the interior and exterior walls, while the remainder, such as the roof, was constructing using traditional methods. Habitat for Humanity hopes that 3D printed homes can be a solution for affordable housing as well as labor shortages in extreme climates and environments.\nPERI: Project Milestone.\nThe first 3D printed residential building in Germany was constructed in September 2020 by PERI, using COBOD's BOD2 printer and Heidelberg Cement's concrete mixture. 24 concrete elements were printed at a facility and then transported to the site for assembly. The printer created 1 m2 of wall every 5 minutes, completing the 160m2 home by November 2020. Only two operators were required to print the walls, which included water placement, electricity, and pipe connections.\nNijmegen, Netherlands: Pedestrian Bridge.\nIn 2021, the Dutch city of Nijmegen revealed the world's longest 3D printed concrete pedestrian bridge, spanning 29 meters. It was estimated that 3D printed saved about 50% in materials because concrete was only placed where structural strength was required. 3D printed bridge components were manufactured by BAM and Weber Beamix offsite, where it was then transported and assembled on-site. The previous record holder for the longest 3D printed concrete bridge was 26 meters, constructed by Tsinghua University in Shanghai.\nEconomic Impacts.\nIn terms of cost and economics, one advantage of 3D printed concrete is that it does not require formwork, which is used to form the mold for conventional concrete pouring. Formwork can account up to 50% of total concrete construction due to material and labor costs. However, there are costs associated with machinery including the print head nozzles and supplemental monitoring devices. In addition, 3D printed concrete mixtures often differ from conventional concrete with additions of nano-clay, nano-silica, and other chemical admixtures that aid the extrusion process.\nThere are indirect economic benefits from 3D printed concrete in terms of productivity. The construction sector is often highly traditional and for the most part, processes have remained similar over the past decades. This is in large part because current processes are still effective in many construction applications. For example, a study by Garcia de Soto compared a robotically fabricated and conventionally constructed wall assembly with different degrees of complexity and found that that conventional construction outperformed robotic fabrication for simpler walls, while the robot was more productive as geometric complexity increased. There was no additional cost due to robotic fabrication and for both cases, material production was the driving factor for cost, as opposed to construction procedures.\nEnvironmental Impacts.\nThe environmental impact of 3D printed concrete is heavily dependent on the processes and materials used for a given project. 3D printed concrete has the potential to reduce material in the production of concrete due to the elimination of formwork, but the specialized admixtures and required technology may have just as much of an impact on the environment as conventional concrete construction. A cradle to grave life-cycle assessment (LCA) comparing the environmental impact of a conventionally constructed concrete wall with a 3D printed concrete wall revealed that the 3D printed alternative only reduced environmental effects when no reinforcement was used. The LCA impacts of global warming potential, acidification potential, eutrophication potential, and smog formation potential were used to measure environmental impacts. Once reinforcement was introduced to the 3D printed concrete structure, these impacts were greater than conventional construction methods, specifically for global warming and smog formation potential.\nAnother LCA conducted a similar study comparing conventional and 3D printed concrete walls but varied the complexity of the structure. It was found that as the complexity of the structure increased, the 3D printed method how a lower environmental impact. This was mostly due to the ability of 3D printed concrete to achieve complex forms while saving building materials in terms of formwork and concrete volume. Overall, the environmental impact of 3D printed concrete is influenced by the structure's design and how well the engineer can optimize material usage. On a material basis, the environmental impacts are similar to that of conventional concrete, as a cement binder is still required. However, the streamlined construction process that comes with 3D printing decreases material waste and onsite emissions.\nChallenges and Limitations.\nThere are several limitations that prevent 3D concrete printing from being widely adopted throughout the construction industry. First, the material palette that can be used for 3D printed concrete is limited, particularly due to nozzle extrusion and the deposition process of concrete layers, which introduces the challenge of premature collapsing. Therefore, research on material properties and developing high quality cementitious materials that comply with both structural concrete codes 3D printing applications is a current area of focus. Due to the sensitivity of a concrete mix, a change cement type, aggregate, or admixture will impact concrete properties and behavior.\nCurrent building codes consider concrete has a homogenous material when in the reality, concrete is anisotropic. This anisotropy is further exposed with printed layers, so new methods for estimating deformations and cracking must be developed. In addition, current material testing for concrete consists of cylindrical specimens in accordance with ASTM C39. There is currently no systematic or theoretical basis for 3D printed concrete, especially when it comes to standard testing.\nCurrent 3D printed projects have been limited to model prototyping and low-rise, large area buildings as opposed to high-rise commercial buildings because of restrictions in 3D printer technology. Printers need to be compatible with the height of the building, so additional research in 3D printer stability and design is required. There are also challenges with reinforcement in 3D concrete printing, which is required for taller structures. See reinforcement for 3D concrete printing for more details.\nResearch and Development.\nPioneering research on the topic of 3D concrete printing is conducted at the ETH Zurich, Loughborough University, Swinburne University of Technology, Eindhoven University of Technology, and the Institute for Advanced Architecture of Catalonia, among many other institutions.\nConferences.\nDue to the increased interest in 3D concrete printing both from industry and academia, a number of conferences have started internationally. Two industry-focused international conferences were organized in February and November 2017 by 3DPrinthused in Copenhagen. Subsequently, the biannual Digital Concrete academic conference was organized at the ETH Zürich in 2018, the Eindhoven institute of Technology in 2020 and at the University of Loughborough in 2022. A parallel series of recurring conferences, focusing on the Asia-Pacific region, was organized at the Swinburne University of Technology in 2018, Tianjin University in 2019, and Shanghai Tongji and Hebei universities in 2020.\nRelated topics.\nConcrete printing can be used directly to produce the final part, or indirectly, to produce formwork in which concrete is cast or sprayed.\n3D-printed formworks address some of the major challenges of 3D concrete printing. Reinforcement bars can be integrated conventionally, and the conventionally cast or sprayed concrete complies with building codes. Additionally, the surface quality of concrete is significantly better than in 3D concrete printing. To achieve a smooth surface, the 3D-printed formworks can be coated or polished.\n3D-printed concrete as formwork.\n3D concrete printing with layered extrusion has been used to produce stay-in-place formworks for casting concrete. In this approach, a thin shell, consisting of one or two 3D-printed contours is produced in a first step, either in a prefabrication plant or directly in situ. Subsequently, reinforcement cages are installed and secured in position. Finally, concrete is cast inside the shell, either in one go, or in several steps to prevent the build up of hydrostatic pressure in the lower sections of the formwork.\nFor structural calculations, the 3D-printed shell is usually ignored, and only the cast concrete is considered load-bearing. However, the 3D-printed shell may be considered for the necessary concrete reinforcement cover that protects the steel from corrosion.\n3D-printed formworks for concrete.\nAlternatively, 3D printing with non-cementitious materials can be employed for the production of formworks for concrete. Extrusion printing with clay, foam, wax, and polymers, as well as binder jetting with sand and stereolithography have been used for the fabrication of formworks for architectural concrete components.", "Engineering,_Manufacturing": 0.9998992682, "qwen": "Yes"}
{"id": "69645810", "revid": "11308236", "url": "https://en.wikipedia.org/wiki?curid=69645810", "title": "OScar (Danish automobile)", "text": "OScar is a limited production sports car produced in Denmark from 1983 to 1986. The car was built by Ole Sommer, a prominent automobile importer and dealer.\nOle Sommer.\nOle Sommer was a Danish importer of automobiles and car enthusiast. He found business success importing Volvo, Renault and Jaguar cars into Denmark. Sommer had an interest in producing a car in Denmark and in the 1970s built a few cars called Joker which were a type of beach buggy based on a Volvo 140. In the 1980s, Sommer set his sights on building a sports car. Sommer later established an automotive museum. He died in 2018.\nOScar.\nThe car was named OScar for \"Ole Sommer car\". Sommer imported fiberglass body shells based on the AC Cobra from BRA in the United Kingdom. Unlike the multitude of other manufactures who created AC Cobra replicas or imitations, Sommer wanted to use Volvo underpinnings.\nThe car was built on a custom frame. The engines available were from Volvo: they were straight-four turbocharged Redblocks of the B19 and B23 variety. Customers were offered the option of up-tuning the engine for more than the standard horsepower from the Volvo engine.\nOScar featured a Volvo front axle and steering assembly from a 140 and a rear axle from a 240. Electronic components were lifted from a 340. The transmission was a Volvo M46 four-speed. Remaining components were hand-made at Sommer's facility including the exceptionally large 70 liter fuel tank. Instrumentation was custom produced by VDO in Germany.\nSommer had envisaged a larger scale production than the 20 units that were produced. Automotive regulations, including crash testing, made it difficult to sell the car. Volvo also refused to let Sommer use his Volvo dealer network to sell the car.", "Engineering,_Manufacturing": 0.9992895722, "qwen": "Yes"}
{"id": "4707409", "revid": "990214", "url": "https://en.wikipedia.org/wiki?curid=4707409", "title": "Manufacturing clause", "text": "The Manufacturing clause is a clause contained in copyright legislation requiring that as a condition of obtaining copyright, all copies of a work must be printed or otherwise produced domestically, from plates set domestically, rather than imported. In the United States, a manufacturing clause was included in the International Copyright Act of 1891, which allowed certain non-resident aliens to obtain U.S. copyrights for the first time. The clause initially covered books, maps, photographs, and lithographs, and was subsequently extended to periodicals as well. Its extension to all other media was proposed in the 1897 Treloar Copyright Bill, which failed in committee. The manufacturing clause did not expire until 1986, keeping the United States out of the Berne Convention until 1989.", "Engineering,_Manufacturing": 0.9849418998, "qwen": "Yes"}
{"id": "4711264", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=4711264", "title": "Ball differential", "text": "A ball differential is a type of differential typically used on radio-controlled cars. It differs from a geared differential by using several small ball bearings rotating between two plates, instead of bevel gears.\nHistory.\nThe first ball differential for Radio-controlled Cars was designed by Cecil Schumacher, a British motor sport engineer working at Cosworth and founder/owner of his eponymous model brand. Although a patent was applied for, it was denied as the idea had already been implemented into a lawn mower. Radio-controlled cars were still a new application for the ball differential and Schumacher is generally considered the modern day inventor of the concept. Such was the popularity of the ball differential, originally applied in 1/12 on-road cars, that he formed his eponymous company.\nTo this date ball differentials remain very popular in the radio-controlled car market. They are used on almost every 1/12 on-road, scale touring car (although the sealed gear differential is gaining popularity in this class) and produced by many manufacturers. In these classes they are regarded as the industry standard. Schumacher Racing Products even use ball differentials on their nitro truck range, these however use strong materials and larger and harder ball bearings.\nBasic principles.\nRadio-controlled car manufacturers use the same basic design Schumacher created in the 1980s. The main part of the differential is a drive gear (or pulley in a belt transmission) with multiple holes cut through it, following its outside diameter. These holes are slightly larger than the width of the ball bearings, so that the balls, commonly around 2 mm diameter in a model car, sit inside the holes of the gear/pulley.\nOn either side of the gear are the thrust washers. The thrust washers are pushed against the ball bearings inside the gear by Belleville washers. On one side of the gear is an adjusting collar, which allows for adjustments in the amount of slip allowed by the differential. A thrust bearing (or thrust race), on the opposite side of the gear, is used to stop the differential from loosening the retaining screw holding the output cups, used to attach the differential to the axle, onto the differential.\nAs the screw is tightened it pushes the Belleville and thrust washers onto the gear/pulley. This creates contact between the washers and ball bearings inside of the gear/pulley. The friction created by the contact between the washers and ball bearings is, aided by grease (commonly silicone grease), designed so that as one washer moves, the ball bearings rotate.\nAs the washer on one side of the gear rotates, the rotation of the balls causes the other washer to rotate in the opposite direction, because any rotating ball will have opposite sides moving in opposite directions .\nDifferential movement is achieved through the process of the thrust washers rotating with the ball bearings. The retaining screw is designed so the differential can be easily adjusted by tightening or loosening the screw, consequently changing force. This makes the differential more adjustable than geared differentials, but there is a lower limit since the drive is by friction so there is always some limited slip action.\nThere are several types of balls used in this type of differential. Some of the most common ball materials used by high end racers are ceramic and tungsten based. The advantage to something like ceramic based balls is that they are much harder, and have a longer life expectancy. Oftentimes when using less hard materials, the balls will \"flat spot\" causing a semi locked direction of the ball. This causes the differential to not turn with a smooth feeling and leaves it with an overall \"gritty\" feeling.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "11786725", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=11786725", "title": "Jig (tool)", "text": "A jig is a type of custom-made tool used to control the location and/or motion of parts or other tools.\nDescription.\nA jig's primary purpose is to provide repeatability, accuracy, and interchangeability in the manufacturing of products. \nAn example of a jig is when a key is duplicated; the original is used as a jig so the new key can have the same path as the old one. Since the advent of automation and computer numerical controlled (CNC) machines, jigs are often not required because the tool path is digitally programmed and stored in memory. Jigs may be made for reforming plastics.\nJigs or templates have been known long before the industrial age. There are many types of jigs, and each one is custom-tailored to do a specific job.\nDrill jig.\nA \"drill jig\" is a type of jig that expedites repetitive hole center location on multiple interchangeable parts by acting as a template to guide the twist drill or other boring device into the precise location of each intended hole center. In metalworking practice, typically a hardened drill bushing lines each hole on the jig plate to keep the tool from damaging the jig.\nDrill jigs started falling into disuse with the invention of the jig borer.\nSince the widespread penetration of the manufacturing industry by CNC machine tools, in which servo controls are capable of moving the tool to the correct location automatically, the need for drill jigs (and for the jobs of the drill press operators who used them) is much less than it used to be.\nPCB jig.\nPrinted circuit board (PCB) jigs are used to test PCBs. They have a dump board inside the jig which can find faults in the PCBs.\nJewelry jig.\nA jig used in making jewelry, a specific type of jig, is a plate or open frame for holding work and helping to shape jewelry components made out of wire or small sheets of metal. A jig in the jewelry making application is used to help establish a pattern for use in shaping the wire or sheets of metal. In the jewelry application, the shaping of the metal is done by hand or with simple hand tools like a hammer.", "Engineering,_Manufacturing": 1.0000061989, "qwen": "Yes"}
{"id": "11789067", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=11789067", "title": "Compatible ink", "text": "Compatible ink (or compatible toner) is manufactured by third-party manufacturers and is designed to work in designated printers without infringing on patents of printer manufacturers. Compatible inks and toners may come in a variety of packaging including sealed plastic wraps or taped plastic wraps. Regardless of packaging, compatible products are generally priced lower than original equipment manufacturer (OEM) brand inks and toners.\nWhile there has been considerable debate and litigation involving the ink and toner patents of printer manufacturers, third-party manufacturers continue to thrive. Manufacturers of compatible ink and toner products currently control about 25% the ink and toner market well over $8 Billion annually.\nTypes.\nCompatible ink is manufactured for several types of machines including fax machines, laser printers, inkjet printers, multifunction printers, and copiers. Aside from compatible products, three other sources of consumables are also available to supply these machines, including OEM brand ink and toner, remanufactured toner and ink cartridges, and refilled ink and toner cartridges. Compatible ink manufacturers differentiate their product by using all new parts, whereas other ink replacements recycle used OEM parts. Compatible ink and toner products tend to offer greater value than original, genuine OEM ink and toner cartridges. Reducing cost for the end user, ink and toner manufactured by third-party manufacturers is classified as compatible when consisting of new parts for a third party printer.\nComparison of performance, quality and reliability.\nThe performance of a printer cartridge needs to be measured by parameters like:\nA comparison between OEM and compatible cartridges for a specific printer needs to take into account the above parameters. For example, a remanufactured cartridge may for example be purchased cheaper, but may not print out as many useful pages. Reliability and consistency associated with an OEM cartridge may be more important than price, for example, when printing output for important business.\nOne independent test in 2004 on using a compatible ink for one type of printer showed little or no difference in quality between the compatible and OEM products.\nAll types of compatible ink cartridges are different and vary from supplier to supplier. This is due to the type of ink in the printer, the chips (or no chip) on the cartridge and the actual manufacture of the cartridge itself.\nIn terms of comparisons with suppliers, prices, quality and comparisons with original oem cartridges. This can vary also by manufacturer and printer. Some compatible cartridges will work perfectly in some printers.", "Engineering,_Manufacturing": 0.9568978548, "qwen": "Yes"}
{"id": "2973049", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=2973049", "title": "Linishing", "text": "Linishing is the process of using grinding or belt sanding techniques to improve the flatness, smoothness and uniformity of a surface and its finish. The process takes multiple stages, and a finer abrasive surface is typically used each time. Abrasive brushes and linishing belts are typically used, the latter being a machine similar to a belt sander used for large surfaces. Large linishing belts are used in large-scale industrial linishing processes. Hand tools similar to linishing belts but much smaller and more suitable for small surfaces are also used.", "Engineering,_Manufacturing": 1.0000035763, "qwen": "Yes"}
{"id": "57366937", "revid": "1167530583", "url": "https://en.wikipedia.org/wiki?curid=57366937", "title": "List of capacitor manufacturers", "text": "A capacitor is a passive device on a circuit board that stores electrical energy in an electric field by virtue of accumulating electric charges on two close surfaces insulated from each other. This is a list of capacitor manufacturers (past and present) and their headquarters location.\nSources.\n[[Category:Capacitor manufacturers| ]]\n[[Category:Lists of manufacturers|Capacitors]]", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "13737492", "revid": "211905", "url": "https://en.wikipedia.org/wiki?curid=13737492", "title": "Frequent deliveries", "text": "Frequent deliveries are a largely ignored but powerful way of leveling apparent demand within a supply chain and thereby reducing Mura. What is perhaps not so obvious is that this will reduce inventory levels and thereby assist progress along the Lean journey at the same time. The historical focus upon carrying full loads, sometimes of only one product, reduces the unit cost of transport but has sometimes hidden the true costs associated with achieving those transport discounts. It is also possible to gain some of these benefits by 'faking' frequent deliveries at the supply site.\nPrinciples.\nReducing production lot size and raising delivery frequency.\nIf we{who?|date=January 2019]} model this idea using a factory that produces three products (Triangles, Circles and Squares) and is making a regular daily delivery to its customer at the end of each day then we can represent this as below.\nStock builds up during the day until the factory has completed the production campaign of three products each of which is produced in a lot of four. After each lot of four a line-changeover happens, there are in fact three as we must include the one before the first production lot. Stock builds here to a maximum of twelve units. If the number of changeovers were doubled to six then the stock levels would remain the same all the stock is still on site until the shipment.\nThe customer is receiving a mix of products that it is likely that they consume (or their in-stock equivalent) during, say, the next day. If the customer consumes the provided products during the day then their stock level will decrease by twelve over the day.\nSo if the customer will agree to receive half the daily shipment of each product halfway through the day and the second half at the original time of end of day and we reduce lot sizes by a factor of two the factory schedule would look like this.\nWe now see that the benefits of the lot size reduction in the stock levels, both at the customer and at the supplying factory. Stock at both locations has been reduced by six. A possible downside for the factory is that it now has twice the changeovers (See Single-Minute Exchange of Die (SMED)).\nIf we take this to the extreme where the factory now has a changeover after every unit of production (single piece flow) and where shipments occur after every campaign (every product has been made) then the factory has this situation.\nNow stock levels, again at the customer and supplier, are down to three from twelve. To achieve this cost effectively the changeovers must be very quick.\nJust raising delivery frequency.\nSo starting from the same original situation.\nThe factory chooses to just make the deliveries more frequent but not change production lot size, and to keep some extra stock so that deliveries can be exactly as in the model where lot sizes were changed as well.\nHere, although an extra stock of two is constantly being held it can be seen that the deliveries still reduce the holding by six giving a net benefit of four at the factory and six at the customer. This is without changing the production schedule.\nIf, again, this is taken to the extreme where deliveries are going to be made of one unit of each product and stock keeping adjusted to make this possible then this situation is seen.\nHere, although an extra stock of three is constantly being held it can be seen that the deliveries still reduce the holding by nine giving a net benefit of six at the factory and nine at the customer. This is still without changing the production schedule.\nSummary.\nSo from this example it can be seen that just increasing delivery frequency reduces the stock held in the system. This is no surprise to those in the context of station to station within a factory. It does seem to surprise many when used in the context of supplier to customer. The summary of this argument is in the table below.\nImplementation.\nSo now the question is how to achieve this more frequent delivery. Well in fact many of the benefits within the factory can be achieved by 'faking' frequent deliveries while discussions with the customer about actual delivery frequencies takes place.\nFaking frequent deliveries.\nThe removal of items in the factory from the 'manufacturing system' will trigger the resupply that we wish to smooth via kanban or other signals. The frequent deliveries will provide a smoother sequence of smaller resupply signals. So by 'faking it' what is meant is that the actual delivery schedule will be de-coupled from the resupply triggers in the factory.\nThis can be done by marking a position on the floor, say a rectangular outline of perhaps the same size as the truck, in the loading bay and designating it to be a specific planned delivery or part of one. Let's call that outline a 'virtual truck'. Clearly if all the items for the delivery were now loaded into the virtual truck then the impact on demand signals into the factory would be the same as a real truck load. The secret here is to schedule a steady flow of items from the factory into the virtual truck so that demand appears as flat as possible. Obviously this may seem like 'smoke and mirrors' since the goods are still actually in the loading bay. The importance is that demand and supply are now decoupled. So whilst a real truck can still be loaded at the required speed, from the virtual truck, the signals for resupply passing via kanbans etc. back into the factory have created a smooth demand. This method can also be used to give early warning to the factory that it is falling behind the required schedule if it is to have all goods ready for shipment when the real truck arrives.\nThe downside of this trick is that there are now two movements of the goods, one to the virtual truck and one from it to the real truck.\nActual frequent deliveries.\nSince these need to meet agreement with the customer these will be less flexible than the 'virtual truck's' unless they are part of an internal process. Between 1982 and 1990 Toyota reorganised its service and crash parts business and as part of that it established Local Distribution Centres (LDCs) in each metropolitan centre. It also encouraged dealers to work intensively with customers so that maintenance was scheduled sufficiently in advance that parts requirements could be precisely predicted.\nBecause the LDCs are so close to the dealers it was possible to establish a 'milk run' which visited every dealer every two hours. So when the service is booked a preliminary order is prepared for the required parts. The day before the scheduled service the customer is called to confirm the service and then a firm order to the LDC is placed for delivery on the next 'milk run'. Finally, when the car arrives for its service it is inspected and any other required parts ordered for delivery with 2–4 hours (the next run). This has resulted in very significant stock reductions throughout the system as the table below illustrates.", "Engineering,_Manufacturing": 0.9686661959, "qwen": "Yes"}
{"id": "13747119", "revid": "43265029", "url": "https://en.wikipedia.org/wiki?curid=13747119", "title": "Shifting bottleneck heuristic", "text": "The Shifting Bottleneck Heuristic is a procedure intended to minimize the time it takes to do work, or specifically, the makespan in a job shop. The makespan is defined as the amount of time, from start to finish, to complete a set of multi-machine jobs where machine order is pre-set for each job. Assuming that the jobs are actually competing for the same resources (machines) then there will always be one or more resources that act as a 'bottleneck' in the processing. This heuristic, or 'rule of thumb' procedure minimises the effect of the bottleneck. The Shifting Bottleneck Heuristic is intended for job shops with a finite number of jobs and a finite number of machines.\nUses.\nThe Shifting Bottleneck Heuristic is used in manufacturing and service industries that include job shops with constraints on the order that the machines must be used for each job. A good example of a service industry that may use this technique is a hospital. The different areas within a hospital, such as physical examination, x-ray booth, cat scan, or surgery, could all be considered machines for this particular application. A precedence constraint in this context is when one machine must be used before another machine on any given job (or patient). These types of problems with multiple machines are known to be computationally very difficult. The processing time of each job on each machine is given (see chart on right for an example). Job \"j\" being performed on machine \"i\" is denoted \"ij\". It is assumed that each machine can only work on one job at a time. The objective is to determine the schedule that will produce the shortest makespan.\nProcedure.\nFirst graph.\nThe first step is to draw out the precedence constraints in a graphical form called a graph (See Original Drawing picture). Each job originates at the \"source\", which we will label U on the graph. Each job will finish in a \"sink\" of jobs, which we will label V on the graph. Each row of nodes in the graph represents a job. Each node on the graph represents a task that is part of the job, the second number confirms the job being performed and the first number indicates what machine is being used for this task. At this point, the initial throughput time of each job should be calculated by adding up the processing times that the job takes on each of the machines (or rows). After the throughput time for each job has been calculated, the makespan for the system is determined by the longest throughput time of any individual job. This assumes no resource conflicts and gives a makespan of 22.\nFirst iteration.\nThe next step is to determine which resource/machine is currently the bottleneck. This is done by considering the production time, denoted \"pij\", that each job takes on each machine, the release time of each job on each respective machine, and the due date of each job for each respective machine. The release time, denoted \"rij\", is determined by adding up the processing times of job \"j\" on the machines that precede machine \"i\" in the job order of job \"j\". The due date, denoted \"dij\", is determined by subtracting the processing times of job \"j\" on the machines succeeding the machine \"i\" in the job order from the makespan. Once all of this is determined, the minimum lateness for each machine needs to be determined. This is accomplished by finding the path for each machine that reduces the maximum lateness seen for all jobs on the respective machine. This can be done using a branch and bound technique for example. It can also be approximated using an other heuristic such as the earliest due date heuristic. Once the maximum lateness is determined for each of the respective machines, the machine with the largest maximum lateness is the bottleneck. If there is no maximum lateness on any of the machines, one can draw all of the machines’ optimal sequences in the job diagram. If there are two machines with the same maximum lateness, either one can be chosen for the bottleneck. All of this work is considered the first iteration.\nOnce the bottleneck has been determined, the path for the machine needs to be included in the graph of jobs (See Iteration 1 Drawing, where the colored arrows represent disjunctive constraints). These new paths can be considered the disjunctive constraints and they need to be taken into consideration when determining the new makespan. The disjunctive constraints are the machine constraints in our job shop. The new makespan will be the old makespan plus the maximum lateness of the machine determined to be the bottleneck.\nSecond iteration.\nThe next step is to perform a new analysis for each of the remaining machines. The differences now are there is a new makespan, and the precedence constraints need to be considered as well as the disjunctive constraints when determining the release date of each job on the machine. The longest path to get from the \"source\" U to the respective job, coming from comparing the release times of the preceding jobs for disjunctive constraints and precedence constraints, will be the new release date. The due dates will be the time that the given job needs be finished on the respective machine to still have enough time to finish the job on the proceeding machines within the makespan. This is the length of the longest path from the job to the \"sink\" V. The proceeding jobs are known from the precedence constraints. \nAgain, determine which machine is the new bottleneck. Add the new disjunctive constraints to the graph (see Iteration 2). This is considered the second iteration. The new makespan is the old makespan plus the maximum lateness from the new bottleneck. Again, if the maximum lateness on all machines is zero then use all the paths for the disjunctive constraints on the drawing and the makespan is still the same as it was before. \nFurther iterations.\nThis process is repeated until all machines have been accounted for or the maximum lateness is zero on all respective remaining machines. Each time the process is repeated, it is considered an iteration and all of the disjunctive constraints may be drawn on the job and machine diagram. For our example, the next iteration provided us with zero for the maximum lateness on machines 3 and 4, so their optimal sequences can be included in the drawing (see Iteration 3). \nAt this point the Shifting Bottleneck Heuristic is complete. The drawing should now include all precedence constraints and all disjunctive constraints. The final makespan is the original makespan plus all of the maximum latenesses from each of the respective bottlenecks. It is the lowest amount of time needed complete all of the jobs given these machine and precedence constraints.\nReferences.\nPinedo, Michael. Planning and Scheduling in Manufacturing and Services. Springer Science+Business Media, LLC. 2005. Pages 87–93. .", "Engineering,_Manufacturing": 0.9999568462, "qwen": "Yes"}
{"id": "32534667", "revid": "41195652", "url": "https://en.wikipedia.org/wiki?curid=32534667", "title": "Chip formation", "text": "Chip formation is part of the process of cutting materials by mechanical means, using tools such as saws, lathes and milling cutters.\nThe formal study of chip formation was encouraged around World War II and shortly afterwards, with increases in the use of faster and more powerful cutting machines, particularly for metal cutting with the new high speed steel cutters. Pioneering work in this field was carried out by Kivima (1952) and Franz (1958).\nChip formation is usually described according to a three-way model developed by Franz. This model is best known within the field of machine tool design, although it is also used when an application area, such as woodworking, requires a vocabulary to describe chip formation in more detail than is usually attempted.\nChip classification.\nThe first three chip types are the original characterisation, by Dr. Norman Franz. The type of chip that forms depends on many factors, of both tool and material. In general, main factors are the angle formed by the edge faces of the tool and also the angle at which this is presented to the surface.\nSharpness of the cutting tool does not usually define the \"type\" of chip, but rather the \"quality\" of the chip, and the clear distinctions between types. A blunt tool produces a degenerate chip that is large, torn and varies from one means of formation to another, often leaving behind a poor quality surface where this means changes.\nType I chip.\nType I chips form when a material splits \"ahead\" of the cutting edge, owing to some upwards wedge action of the tool exceeding the \"tensile\" strength of the material, perpendicular to the surface. They are thus particularly important in fibrous materials, such as wood, where individual fibres are strong but they may be levered apart relatively easily. Type I chips generally form in cutting by tools with shallow cutting angles.\nType I chips may form long, continuous swarf, limited in size only by the length of cut.\nThis is the idealised chip formation for wood shavings, particularly those produced by a well-tuned plane with a finely adjusted mouth.\nType II chip.\nType II chips form when a shearing force is produced by the wedge of the tool angle. The material fails along a short angled plane, from the apex of the tool edge, diagonally upwards and forwards to the surface. The material deforms along this line, forming an upward curling chip. These chips generally form from intermediate cutting angles.\nType II chips may form in ductile materials, such as metals.\nType II chips may also form long, continuous swarf.\nType III chip.\nType III chips form a compression failure of the material, ahead of a relatively obtuse cutting angle, approaching 90°. In some weak or non-ductile materials this may form an acceptable chip, usually as a fine dust, but often it gives rise instead to a random \"snowplough\" effect where the waste material is bunched up ahead of the tool but not cleared decisively away as a well-formed chip.\nThis type of chip is formed by routers. It is also formed by woodworking scrapers, although when properly sharpened and used, these form such a thin Type III chip that it instead appears as a well-formed Type II chip. Their waste chip is thin enough that the compression failure volume is small enough to act as for the well-defined shear plane of the Type II.\nType 0 chip.\nThis type was characterised later, by William McKenzie (1960).", "Engineering,_Manufacturing": 0.9999148846, "qwen": "Yes"}
{"id": "32537475", "revid": "9895903", "url": "https://en.wikipedia.org/wiki?curid=32537475", "title": "Characteristic based product configurator", "text": "A characteristic-based product configurator is a product configurator extension which uses a set of discrete variables, called characteristics (or features), to define all possible product variations.\nCharacteristics.\nThere are two characteristic types:\nConstraints.\nThe range of characteristic-value combinations is reduced by a variety of constraints that define which combinations can, cannot, and must occur alongside each other. These constraints can be reflective of technological or commercial constraints in the real world.\nThe constraints can represent:\nCharacteristic filters.\nThe use of characteristics permits the user to abstract the finished product by describing filter conditions, which describe subsets of product variations using boolean functions on the characteristics:\nClosed or open configuration.\nUsing a characteristic-based configurator, it is possible to define a product variation in two ways:\nApplications.\nSome examples of applications where using a characteristics-based product configurator may be advantageous are:\nExamples.\npCon.planner from EasternGraphics is an OFML-based complex product configurator used for interior design.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "32546455", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=32546455", "title": "Microextrusion", "text": "Microextrusion is a microforming extrusion process performed at the submillimeter range. Like extrusion, material is pushed through a die orifice, but the resulting product's cross section can fit through a 1mm square. Several microextrusion processes have been developed since microforming was envisioned in 1990. Forward (ram and billet move in the same direction) and backward (ram and billet move in the opposite direction) microextrusion were first introduced, with forward rod-backward cup and double cup extrusion methods developing later. Regardless of method, one of the greatest challenges of creating a successful microextrusion machine is the manufacture of the die and ram. \"The small size of the die and ram, along with the stringent accuracy requirement, needs suitable manufacturing processes.\" Additionally, as Fu and Chan pointed out in a 2013 state-of-the-art technology review, several issues must still be resolved before microextrusion and other microforming technologies can be implemented more widely, including deformation load and defects, forming system stability, mechanical properties, and other size-related effects on the crystallite (grain) structure and boundaries.\nDevelopment and use.\nMicroextrusion is an outgrowth of microforming, a science that was in its infancy in the early 1990s. In 2002, Engel \"et al.\" expressed that up to that point, only a few research experiments involving micro-deep drawing and extruding processes had been attempted, citing limitations in shearing on billets and difficulties in tool manufacturing and handling. By the mid- to late 2000s, researchers were working on issues such as billet flow, interfacial friction, extrusion force, and size effects, \"the deviations from the expected results that occur when the dimension of a workpiece or sample is reduced.\" Most recently, research into using ultrafine-grained material at higher formation temperatures and applying ultrasonic vibration to the process has pushed the science further. However, before bulk production of microparts such as pins, screws, fasteners, connectors, and sockets using microforming and microextrusion techniques can occur, more research into billet production, transportation, positioning, and ejection are required.\nMicroextrusion techniques have also been applied to bioceramic and plastic extrusion and the manufacture of components for resorbable and implantable medical devices, from bioresorbable stents to controlled drug release systems. \nMicroextrusion processes.\nLike normal macro-level extrusion, several similar microextrusion processes have been described over the years. The most basic processes were forward (direct) and backward (indirect) microextrusion. The ram (which propels the billet forward) and billet both move in the same direction with forward microextrusion, while in backward microextrusion has the ram and billet moving in opposite directions. These in turn have been applied to specialized applications such as the manufacture of microbillet, brass micropins, microgear shafts, and microcondensers. However, other processes have been applied to microextrusion, including forward rod–backward cup extrusion and double cup (one forward, one backward) extrusion.\nStrengths and limitations.\nStrengths of microextrusion over other manufacturing processes include its ability to create very complex cross-sections, preserve chemical properties, condition physical properties, and process materials which are delicate or dependent on physical or chemical properties. However, microextrusion has some limitations, though primarily related to the need for improvement of the relatively young process. Dixit and Das described it thus in 2012:\nWith the scaling down of dimensions and increasing geometric complexity of objects, currently available technologies and systems may not be able to meet the development needs. New measuring devices, principles and instrumentation, tolerance rules, and procedures have to be developed. Materials databases with detailed information on various materials and their properties/interface properties including microstructures and size effect would be very useful for product innovation and process design. More studies are necessary on micro/nanowear and damages/failures of the micromanufacturing tools. The forming limits for different types of materials at the microlevel must be prescribed. More specific considerations must be incorporated into the design of machines that are scaled down for microforming to meet engineering applications and requirements.", "Engineering,_Manufacturing": 1.0000042915, "qwen": "Yes"}
{"id": "31156082", "revid": "12023796", "url": "https://en.wikipedia.org/wiki?curid=31156082", "title": "Anomatic", "text": "Anomatic Corporation manufactures aluminum products, and is a manufacturer of large-quantity aluminum parts for cosmetic companies' packaging including Revlon, Maybelline, Estee Lauder and Mary Kay.\nHistory.\nSince 1965, Anomatic has been manufacturing items ranging from consumer products such as MP3 players, cookware, and baseball bats to industrial applications such as heat sinks and aerospace/aviation components. \nProduct lines.\nThe company produces anodized aluminum packaging for the personal care, makeup, fragrance, automotive, pharmaceutical, health and beauty industries for clients as well as industrial applications. It is headquartered in New Albany, Ohio with additional US manufacturing locations in Newark, Ohio, Blacklick, Ohio, Naugatuck, Connecticut, and an international facility in Suzhou, China. Anomatic’s services include package design, rapid 3D prototyping, metal forming, anodizing, decorating, assembly, and metallization.\nSpecializing in high-volume runs, Anomatic is known as the \"color experts\" for its highly-consistent anodizing process and color matching capabilities. Now vertically-integrated, Anomatic has reinvested to add multiple additional decorative technologies as well as metallization in-house, making the company one of the only metallizing manufacturers in the US to supply the cosmetics industry.\nEnvironmental policies.\nAnomatic is committed to being environmentally responsible. The company has implemented a sustainability plan to reduce energy, waste, water and air pollution as well as recycle and reuse materials. In 2010, Anomatic announced the formation of the Sustainability and Environmental Operations Group which works to expand the company’s sustainable and green operations through Lean, Six Sigma and GMP. The company opened its LEED-certified facility in New Albany, Ohio within the International Personal Care and Beauty Campus and moved its headquarters there.", "Engineering,_Manufacturing": 0.9988712072, "qwen": "Yes"}
{"id": "2940943", "revid": "38455", "url": "https://en.wikipedia.org/wiki?curid=2940943", "title": "Ball detent", "text": "A ball detent is a simple mechanical arrangement used to hold a moving part in a temporarily fixed position relative to another part. Usually the moving parts slide with respect to each other, or one part rotates within the other.\nThe ball is a single, usually metal sphere, sliding within a bored cylinder, against the pressure of a spring, which pushes the ball against the other part of the mechanism, which carries the detent - which can be as simple as a hole of smaller diameter than the ball. When the hole is in line with the cylinder, the ball is partially pushed into the hole under spring pressure, holding the parts at that position. Additional force applied to the moving parts will compressing the spring, causing the ball to be depressed back into its cylinder, and allowing the parts to move to another position.\nApplications.\nBall detents are commonly found in the selector mechanism of a gearbox, holding the selector rods in the correct position to engage the desired gear. Other applications include clutches that slip at a preset torque, and calibrated ball detent mechanisms are typically found in a torque wrench.\nBall detents are one of the mechanisms often used in folding knives to prevent unwanted opening of the blade when carrying.\nBall detents were used in the Curta mechanical calculator to enforce discrete values.\nUse in paintball markers.\nThe term \"ball detent\" is also used when referring to a mechanism in paintball markers designed to prevent the paintball from rolling out of the firing chamber before being fired. Some designs are similar to those outlined above, with a cartridge utilizing a ball bearing in a bore with spring pressure. The cartridge is installed perpendicular to the barrel bore axis, just ahead of where the ball rests before being fired. Other designs use elastic rubber protrusions that block the ball until it is pushed over it by the bolt. Some designs use precisely calibrated rings or \"barrel sizers\" that are selected to have a slightly smaller inner diameter than the outer diameter of the paintballs being used. They rely on simple constriction of the bore to prevent paintballs from rolling through them from the force of gravity. When the marker is fired, the air pressure pushes the ball through the bore, causing it to compress enough to pass through. Paintballs have varying diameters depending on a number of factors; this type of ball detent must be sized correctly to avoid compressing the paintball too much, causing it to burst. If too large of a sizer is selected, balls may roll through it.\nThe cartridge and elastic rubber protrusion type detents are primarily used for open bolt markers, or on closed bolt markers to prevent double feeding (feeding more than one ball when the bolt is open for loading). Closed bolt markers generally use the constriction method to prevent \"roll outs\", a malfunction where the ball completely rolls out of the barrel, causing no paintball to be fired when the trigger is pulled. A partial roll out is when the ball rolls partially through the barrel, causing reduced velocity.", "Engineering,_Manufacturing": 0.9992409945, "qwen": "Yes"}
{"id": "1663983", "revid": "4904587", "url": "https://en.wikipedia.org/wiki?curid=1663983", "title": "Rework (electronics)", "text": "Rework (or re-work) is the term for the refinishing operation or repair of an electronic printed circuit board (PCB) assembly, usually involving desoldering and re-soldering of surface-mounted electronic components (SMD). Mass processing techniques are not applicable to single device repair or replacement, and specialized manual techniques by expert personnel using appropriate equipment are required to replace defective components; area array packages such as ball grid array (BGA) devices particularly require expertise and appropriate tools. A hot air gun or hot air station is used to heat devices and melt solder, and specialised tools are used to pick up and position often tiny components.\nA rework station is a place to do this work—the tools and supplies for this work, typically on a workbench. Other kinds of rework require other tools.\nReasons for rework.\nRework is practiced in many kinds of manufacturing when defective products are found.\nFor electronics, defects may include:\nProcess.\nThe rework may involve several components, which must be worked on one by one without damage to surrounding parts or the PCB itself. All parts not being worked on are protected from heat and damage. Thermal stress on the electronic assembly is kept as low as possible to prevent unnecessary contractions of the board which might cause immediate or future damage.\nIn the 21st century, almost all soldering is carried out with lead-free solder, both on manufactured assemblies and in rework, to avoid the health and environmental hazards of lead. Where this precaution is not necessary, tin-lead solder melts at a lower temperature and is easier to work with.\nHeating a single SMD with a hot-air gun to melt all solder joints between it and the PCB is usually the first step, followed by removing the SMD while the solder is molten. The pad array on the conductor board should then be cleaned of old solder. It is quite easy to remove these residues by heating them to melting temperature. A soldering iron or hot air gun can be used with desoldering braid.\nThe precise placement of the new unit onto the prepared pad array requires skillful use of a highly accurate vision-alignment system with high resolution and magnification. The smaller the pitch and size of the components, the more precise working must be.\nFinally the newly placed SMD is soldered onto the board. Reliable solder joints are facilitated by use of a solder profile which preheats the board, heats all the connections between the unit and the PCB to the melting temperature of the solder used, then properly cools them.\nHigh quality demands or specific designs of SMDs require the precise application of solder paste before positioning and soldering the unit. The surface tension of the molten solder, which is on the board's solder pads, tends to pull the device into precise alignment with the pads if not initially positioned totally correctly.\nReflowing and reballing.\nBall grid arrays (BGA) and chip scale packages (CSA) present special difficulties for testing and rework, as they have many small, closely spaced pads on their underside which are connected to matching pads on the PCB. Connecting pins are not accessible from the top for testing, and cannot be desoldered without heating the whole device to the melting point of solder.\nAfter fabrication of the BGA package, tiny balls of solder are glued to the pads on its underside; during assembly the balled package is placed on the PCB and heated to melt the solder and, all being well, to connect each pad on the device to its mate on the PCB without any extraneous solder bridging between adjacent pads. Bad connections produced during assembly can be detected and the assembly reworked (or scrapped). Imperfect connections of devices which are not themselves faulty, which work for a time and then fail, often triggered by thermal expansion and contraction at operating temperature, are not infrequent.\nAssemblies which fail because of bad BGA connections can be repaired either by reflowing, or by removing the device and cleaning it of solder, reballing, and replacing. Devices can be recovered from scrapped assemblies for reuse in the same way.\nReflowing as a rework technique, similar to the manufacturing process of reflow soldering, involves dismantling the equipment to remove the faulty circuit board, pre-heating the whole board in an oven, heating the non-functioning component further to melt the solder, then cooling, following a carefully determined thermal profile, and reassembling, a process which is hoped will repair the bad connection without the need to remove and replace the component. This may or not resolve the problem; and there is a chance that the reflowed board will fail again after some time. For typical devices (PlayStation 3 and Xbox 360) one repair company estimates that the process, if there are no unexpected problems, takes about 80 minutes. On a forum where professional repair people discuss reflowing of laptop computer graphics chips, different contributors cite success rates (no failure within 6 months) of between 60 and 90% for reflowing with professional equipment and techniques, in equipment whose value does not justify complete reballing. Reflowing can be done non-professionally in a domestic oven or with a heat gun. While such methods can cure some problems, the outcome is likely to be less successful than is possible with accurate thermal profiling achieved by an experienced technician using professional equipment.\nReballing involves dismantling, heating the chip until it can be removed from the board, typically with a hot-air gun and vacuum pickup tool, removing the device, removing solder remaining on the device and board, putting new solder balls in place, replacing the original device if there was a poor connection, or using a new one, and heating the device or board to solder it in place. The new balls can be placed via several methods, including:\nFor the PS3 and Xbox mentioned above, the time is about 120 minutes if all goes well.\nChips are at risk of being damaged by the repeated heating and cooling of reballing, and manufacturers' warranties sometimes do not cover this case. Removing solder with solder wick subjects devices to thermal stress fewer times than using a flowing solder bath. In a test twenty devices were reballed, some several times. Two failed to function, but were restored to full functionality after reballing again. One was subjected to 17 thermal cycles without failing.\nResults.\nProperly carried out rework restores the functionality of the reworked assembly, and its subsequent lifetime should not significantly be affected. Consequently, where the cost of reworking is less than the value of the assembly, it is widely used in all sectors of the electronic industry. Manufacturer and service providers of communications-technologies, entertainment- and consumer-devices, industrial commodities, automobiles, medical technology, aerospace and other high power electronics rework when necessary.", "Engineering,_Manufacturing": 0.9994892478, "qwen": "Yes"}
{"id": "55846595", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=55846595", "title": "Shadow board", "text": "A shadow board is a type of tool board for organizing a set of tools; the board defines where particular tools should be placed when they are not in use. Shadow boards have the outlines of a work station's tools marked on them, allowing operators to identify quickly which tools are in use or missing. The boards are commonly located near the work station where the tools are used. Shadow boards are often used in the manufacturing environment to improve a facility's lean six sigma capabilities.\nShadow boards reduce time spent looking for tools and also reduce losses. They improve work station safety because tools are replaced safely after use, rather than becoming potential hazards.", "Engineering,_Manufacturing": 0.9994681478, "qwen": "Yes"}
{"id": "55855855", "revid": "984042189", "url": "https://en.wikipedia.org/wiki?curid=55855855", "title": "Conductive anodic filament", "text": "Conductive anodic filament, also called CAF, is a metallic filament that forms from an electrochemical migration process and is known to cause printed circuit board (PCB) failures. \nMechanism.\nCAF formation is a process involving the transport of conductive chemistries across a nonmetallic substrate under the influence of an applied electric field. CAF is influenced by electric field strength, temperature (including soldering temperatures), humidity, laminate material, and the presence of manufacturing defects. The occurrence of CAF failures has been primarily driven by the electronics industry pushing for higher density circuit boards and the use of electronics in harsher environments for high reliability applications.\nFailure modes and detection.\nCAF commonly occurs between adjacent vias (i.e. plated through holes) inside a PCB, as the copper migrates along the glass/resin interface from anode to cathode. CAF failures can manifest as current leakage, intermittent electrical shorts, and even dielectric breakdown between conductors in printed circuit boards. This often makes CAF very difficult to detect, especially when it occurs as an intermittent issue. There are a few things that can be done to isolate the fault location and confirm CAF as a root cause of a failure. If the issue is intermittent then putting the sample of interest under combined temperature-humidity-bias (THB) may help recreate the failure mode. In addition, techniques such as cross sectioning or superconducting quantum interference device (SQUID) can be used to identify the failure. \nConsiderations and mitigation.\nThere are several design considerations and mitigation techniques that can be used to reduce the susceptibility to CAF. Certain material selection (i.e. laminate) and design rules (i.e. via spacing) can help reduce CAF risk. Poor adhesion between the resin and glass fibers in the PCB can create a path for CAF to occur. This may depend on parameters of the silane finish applied to the glass fibers, which is used to promote adhesion to the resin. There are also testing standards that can be performed to assess CAF risk. IPC TM-650 2.6.25 provides a test method to assess CAF susceptibility. Additionally, IPC TM-650 2.6.16 provides a pressure vessel test method to rapidly evaluate glass epoxy laminate integrity. This is helpful but it may often be better to use design rules and proper material selection to proactively mitigate the issue.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "39010846", "revid": "41882264", "url": "https://en.wikipedia.org/wiki?curid=39010846", "title": "Lyman filament extruder", "text": " The Lyman filament extruder is a device for making 3-D printer filament suitable for use in 3-D printers like the RepRap. It is named after its developer Hugh Lyman and was the winner of the Desktop Factory Competition.\nThe goal in the competition was to build an open source filament extruder for less than $250 in components that can take ABS or PLA resin pellets, mix them with colorant, and extrude enough 1.75 mm diameter ± 0.05 mm filament that can be wrapped on a 1 kg spool. The machine must use the Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0) license.\nThe use of DIY filament extruders like the Lyman can significantly reduce the cost of printing with 3-D printers. The Lyman filament extruder was designed to handle pellets, but can also be used to make filament from other sources of plastic such as post-consumer waste like other RecycleBots. Producing plastic filament from recycled plastic has a significant positive environmental impact.", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "39021261", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=39021261", "title": "Distributed manufacturing", "text": "Distributed manufacturing also known as distributed production, cloud producing, distributed digital manufacturing, and local manufacturing is a form of decentralized manufacturing practiced by enterprises using a network of geographically dispersed manufacturing facilities that are coordinated using information technology. It can also refer to local manufacture via the historic cottage industry model, or manufacturing that takes place in the homes of consumers.\nEnterprise.\nIn enterprise environments, the primary attribute of distributed manufacturing is the ability to create value at geographically dispersed locations. For example, shipping costs could be minimized when products are built geographically close to their intended markets. Also, products manufactured in a number of small facilities distributed over a wide area can be customized with details adapted to individual or regional tastes. Manufacturing components in different physical locations and then managing the supply chain to bring them together for final assembly of a product is also considered a form of distributed manufacturing. Digital networks combined with additive manufacturing allow companies a decentralized and geographically independent distributed production (cloud manufacturing).\nConsumer.\nWithin the maker movement and DIY culture, small scale production by consumers often using peer-to-peer resources is being referred to as distributed manufacturing. Consumers download digital designs from an open design repository website like Youmagine or Thingiverse and produce a product for low costs through a distributed network of 3D printing services such as 3D Hubs, Geomiq. In the most distributed form of distributed manufacturing the consumer becomes a prosumer and manufacturers products at home with an open-source 3-D printer such as the RepRap. In 2013 a desktop 3-D printer could be economically justified as a personal product fabricator and the number of free and open hardware designs were growing exponentially. Today there are millions of open hardware product designs at hundreds of repositories and there is some evidence consumers are 3-D printing to save money. For example, 2017 case studies probed the quality of: (1) six common complex toys; (2) Lego blocks; and (3) the customizability of open source board games and found that all filaments analyzed saved the prosumer over 75% of the cost of commercially available true alternative toys and over 90% for recyclebot filament. Overall, these results indicate a single 3D printing repository, MyMiniFactory, is saving consumers well over $60 million/year in offset purchases of only toys. These 3-D printers can now be used to make sophisticated high-value products like scientific instruments. Similarly, a study in 2022 found that 81% of open source designs provided economic savings and the total savings for the 3D printing community is more than $35 million from downloading only the top 100 products at YouMagine. In general, the savings are largest when compared to conventional products when prosumers use recycled materials in 'distributed recycling and additive manufacturing' (DRAM).\nSocial change.\nSome call attention to the conjunction of commons-based peer production with distributed manufacturing techniques. The self-reinforced fantasy of a system of eternal growth can be overcome with the development of economies of scope, and here, the civil society can play an important role contributing to the raising of the whole productive structure to a higher plateau of more sustainable and customised productivity. Further, it is true that many issues, problems and threats rise due to the large democratization of the means of production, and especially regarding the physical ones. For instance, the recyclability of advanced nanomaterials is still questioned; weapons manufacturing could become easier; not to mention the implications on counterfeiting and on \"intellectual property\". It might be maintained that in contrast to the industrial paradigm whose competitive dynamics were about economies of scale, commons-based peer production and distributed manufacturing could develop economies of scope. While the advantages of scale rest on cheap global transportation, the economies of scope share infrastructure costs (intangible and tangible productive resources), taking advantage of the capabilities of the fabrication tools. And following Neil Gershenfeld in that “some of the least developed parts of the world need some of the most advanced technologies”, commons-based peer production and distributed manufacturing may offer the necessary tools for thinking globally but act locally in response to certain problems and needs. As well as supporting individual personal manufacturing social and economic benefits are expected to result from the development of local production economies. In particular, the humanitarian and development sector are becoming increasingly interested in how distributed manufacturing can overcome the supply chain challenges of last mile distribution. Further, distributed manufacturing has been proposed as a key element in the Cosmopolitan localism or cosmolocalism framework to reconfigure production by prioritizing socio-ecological well-being over corporate profits, over-production and excess consumption.\nTechnology.\nBy localizing manufacturing, distributed manufacturing may enable a balance between two opposite extreme qualities in technology development: Low technology and High tech. This balance is understood as an inclusive middle, a \"mid-tech\", that may go beyond the two polarities, incorporating them into a higher synthesis. Thus, in such an approach, low-tech and high-tech stop being mutually exclusive. They instead become a dialectic totality. Mid-tech may be abbreviated to “both…and…” instead of “neither…nor…”. Mid-tech combines the efficiency and versatility of digital/automated technology with low-tech's potential for autonomy and resilience.", "Engineering,_Manufacturing": 0.9999939203, "qwen": "Yes"}
{"id": "39050173", "revid": "6046731", "url": "https://en.wikipedia.org/wiki?curid=39050173", "title": "Fixed position assembly", "text": "Fixed position assembly refers to an assembly system or situation in which the product does not move while being assembled, this configuration is usually contrasted in operations management and industrial engineering with assembly lines. Dimensioning this system is very simple: considering CP as productive capacity and T as average assembly time, then N, number of working stations, is given by N=CP*T.", "Engineering,_Manufacturing": 0.9999938011, "qwen": "Yes"}
{"id": "39050345", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=39050345", "title": "Electrospark deposition", "text": "Electrospark deposition is a micro-welding manufacturing process typically used to repair damage to precision or valuable mechanical components such as injection moulding tools. This process may also be referred to as \"spark hardening\", \"electrospark toughening\" or \"electrospark alloying\".", "Engineering,_Manufacturing": 0.9999958277, "qwen": "Yes"}
{"id": "15137009", "revid": "125972", "url": "https://en.wikipedia.org/wiki?curid=15137009", "title": "Parting line", "text": "A parting line, in industrial casting of molds, is the border line in which draft angles change direction. One can check the parting line in the mould or product which divides the two half, i.e; the core and the cavity of a molded part. It is sometimes a starting point for the mold parting surface. In engineering drawing, a parting line is often abbreviated as PL. ASME's Y14.8 standard specifies a symbol for parting line. Engineering applications (seals, tight running molded parts) that require precision for shape control, call for removal of flashes. Many molders will repair or even replace the mold tooling so that the flash is reduced to an acceptable tolerance or eliminated altogether. Secondary operations to remove parting line flash include hand trimming, vibratory tumbling, media blasting and cryogenic deflashing.", "Engineering,_Manufacturing": 0.9999984503, "qwen": "Yes"}
{"id": "41359304", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=41359304", "title": "Iron powder", "text": "Iron powder has several uses; for example production of magnetic alloys and certain types of steels.\nIron powder is formed as a whole from several other iron particles. The particle sizes vary anywhere from 20-200 μm. The iron properties differ depending on the production method and history of a specific iron powder. There are three types of iron powder classifications: reduced iron powder, atomized powder, and electrolytic iron powder. Each type is used in various applications depending on their properties. There is very little difference in the visual appearances of reduced iron powder and atomized iron powder.\nApplications.\nAutomobiles.\nMost iron powders are used for automobile parts. \nOther.\nIron powder is also used for the following:", "Engineering,_Manufacturing": 0.9984515309, "qwen": "Yes"}
{"id": "10645160", "revid": "36320931", "url": "https://en.wikipedia.org/wiki?curid=10645160", "title": "Wire wrapped jewelry", "text": "Wire wrapping is one of the oldest techniques for making handmade jewelry. This technique is done with jewelry wire and findings similar to wire (for example, head-pins) to make components. Wire components are then connected to one another using mechanical techniques with no soldering or heating of the wire. Frequently, in this approach, a wire is bent into a loop or other decorative shape and then the wire is wrapped around itself to finish the wire component. This makes the loop or decorative shape permanent. The technique of wrapping wire around itself gives this craft its name of wire wrapping.\nHistory.\nExamples of wire and beaded jewelry made using wire wrapping techniques date back to thousands of years BC. The British Museum has samples of jewelry from the Sumerian Dynasty, found in the cemetery of Ur that contain spiraled wire components. This jewelry is dated at approximately 2000 BC. Other samples of jewelry from Ancient Rome show wire wrapped loops (one of the important techniques in making wire wrapped jewelry). This Roman jewelry is dated to approximately 2,000 years ago. In the manufacture of this early jewelry the techniques for soldering did not exist. Later, as the technique for soldering developed, the wire wrapping approach continued because it was an economical and quick way to make jewelry components out of wire.\nWire wrapping techniques are not frequently used for mass-produced jewelry because machines can cast (mold) jewelry components faster, more cheaply, and more precisely. The wire wrapping approach to making jewelry is primarily employed by individuals.\nCharacteristics.\nWire wrapped jewelry is jewelry made of wire with mechanical connections instead of soldered connections. The key differences between making jewelry by wire wrapping and other approaches to making jewelry are two-fold;\nA key element in wire wrapped jewelry is a loop made in wire. Loops are connected to one another to make the mechanical connections between components. A \"P\" loop is made by bending the wire until it touches the wire again (but this is too crude looking for serious jewelry use). The best-looking loop is the eye loop, with a full circle of wire centered over the stem of wire (like a lollipop).\nP loops and eye loops are \"open\" loops. This means that the loop can be opened mechanically to allow it to connect to another component, which allows it to open too easily when strained. A stronger (and better looking) loop is the closed loop, where the end of the wire is wrapped around the stem of the loop three or four times, so that the loop is permanent and cannot be opened, this is called a \"wrapped loop\". A connection between two wrapped loops must be performed before the second loop is wrapped closed.\nIn the simplest example of handmade wire wrapped jewelry, a bead is threaded onto a jewelry making finding called a head–pin. The bead is held in place by the \"head\" on the head pin. The portion of the head pin coming out of the opposite side of the bead is essentially wire. This wire is bent into a loop using hand tools and the excess wire is cut off. The resulting bead hanging from a loop is called a \"bead dangle\". To complete a simple earring, the loop in the bead dangle is connected to the loop at the end of an ear wire finding leaving a completed earring.\nTools.\nFour tools are essential and several other tools are useful in the construction of wire wrapped jewelry. The basic tools are a flush cutter, round nose pliers, flat nose pliers and chain nose or bent chain nose pliers. A flush cutter is a special type of cutter that leaves one end of the cut wire flush or flat, while the opposite end of the cut wire is sharp or pointed. Round nose pliers are pliers with conical jaws and are used for making loops in wire. Chain nose or bent chain nose pliers have flat smooth jaws and are used for gripping and holding wire and for bending wire. Flat nose pliers are just what the name implies, they are flat on both inside surfaces and are used to keep areas flat or to make 90-degree bends in your wire.\nOther useful tools used in making wire wrapped jewelry are nylon jaw pliers, a ruler, step jaw pliers, a pin vise to twist the wire, a chasing hammer, an anvil or bench block, a cup bur, loop closing or bent closing pliers and a jewelry making jig.\nWire.\nWire is available is shapes such as round, square, half-round and patterns, such as flat and pre-twisted. It is also available in a variety of materials. Copper and brass wire are easy to shape and manipulate. Copper wire can be hammered quite thin. Brass wire is a little stiffer than copper, but it can be manipulated very easily. Sterling silver is soft enough to manipulate, but holds its shape well once it has been formed. Gold-filled wire is made by fusing a layer of 12-or 14-karat gold to a supporting material. Silver-filled wire is made in the same manner. The bond between the two materials is permanent.\nWire is measured by diameter, which is indicated by gauge numbers. The lower the gauge, the thicker the wire. A 12- or 14-gauge wire is fairly heavy, but ideal for making bangles and chokers. 10-gauge wire is very thick and stiff, while 26-gauge wire is very fine, almost as thin as hair. This thin wire is well-suited for coiling embellishments. 16-gauge wire is good for making jump rings and links for necklaces and bracelets, and 18-gauge wire is good to use for adding embellishments and making finer links.\nPrecious metal wire also comes in three hardnesses:\nSupplies.\nA craftsperson can purchase pre-made components instead of making them. Pre-made components come under the generic name findings. The most important findings used in making jewelry are ear wires, clasps, head pins, and jump rings.", "Engineering,_Manufacturing": 0.9954357743, "qwen": "Yes"}
{"id": "10651348", "revid": "43558034", "url": "https://en.wikipedia.org/wiki?curid=10651348", "title": "Manufacturing in Mexico", "text": "Manufacturing in Mexico grew rapidly in the late 1960s with the end of the US farm labor agreement known as the bracero program. This sent many unskilled farm laborers back into the Northern border region with no source of income. As a result, the US and Mexican governments agreed to The Border Industrialization Program, which permitted US companies to assemble product in Mexico using raw materials and components from the US with reduced duties. The Border Industrialization Program became known popularly as The Maquiladora Program or shortened to The Maquila Program.\nOver the years, simple assembly operations in Mexico have evolved into complex manufacturing operations including televisions, automobiles, industrial and personal products. While inexpensive commodity manufacturing has flown to China, Mexico attracts U.S. manufacturers that need low-cost solutions near-by for higher value end products and just-in-time components.\nLarger foreign firms with global experience can set up operations in Mexico readily. Smaller companies are usually advised to seek professional help from a qualified consulting firm or by working with a partner in Mexico.\nAdvantages.\nMexico's low landed costs are attractive when considered in comparison to other developing country options. It is suited to serve as a manufacturing venue for short to medium-run products that have a high degree of engineered content. Its proximity to the United States enables technical and production personnel to coordinate activities to bridge temporary and physical distances. The closeness to markets, as well as to the consumer base, fulfills the just-in-time requirements of both. Additionally, Mexico's efforts to enforce patent and intellectual property laws are advanced compared with those in place in other low-cost nations. Political risk associated with the country is minimal.\nAlthough the average wage rate in Mexico is higher than in China and other emerging Asian economies, the workforce in Mexico has a large pool of highly educated and skilled engineers. Also, freight charges from China has significantly increased over the years, which make up for the difference in labor cost.\nMethods of operation.\nThere are five common methods by which foreign companies setup manufacturing operations in Mexico.\nContracting.\nCompanies are well advised to consider the contract manufacturing or subcontract manufacture option when the work to be performed requires approximately 25 individuals or less, or is sporadic. Once this number is surpassed, other options would provide savings as a result of economies of scale derived from increased labor content.\nCompanies with high quality requirements must be certain to identify and work with firms capable of meeting and maintaining their exacting standards. If quality standards can be maintained, contract manufacturing / subcontract manufacturing can be the best option for firms seeking to manufacture product without making the large capital and organizational investment required on their own. Manufacturers with high intellectual property content must be assured that such property is protected.\nWhile contract manufacturing or subcontracting has the potential to be an excellent situation for the foreign company due to the fact that the responsibility for production, quality, and delivery is held by the contract manufacturer or subcontractor, it is often very difficult to find a company in Mexico that has the ability to operate as a true contract manufacturer or subcontractor.\nJoint venture.\nA second means by which manufacturers can set up operations in Mexico is through the establishment of a joint-venture agreement with an indigenous party. Joint venturing can be an effective means to achieving organizational goals given the local partner's detailed knowledge of the market and its prevailing conditions. Relationships with firms that have established distribution channels may be of particular value to parties seeking to supply product to domestic markets.\nEstablishing and maintaining a joint-venture relationship can be challenging in that both parties must share a compatibility of organizational culture, as well as pursue similar goals and objectives. Encountering a partner with sufficient similarity of process and purpose can often prove to be a significant challenge.\nWholly owned subsidiary.\nA firm can establish itself in Mexico through the formation of a wholly owned subsidiary. As is the case with initiating operations in any foreign environment, this can be the most complex, costly and risk-laden alternative. In addition to committing the organization to the investment of “bricks and mortar,” the manufacturer must take the time, make the effort and assume the cost of assembling the skill sets required to navigate new waters. Expertise must be sought, acquired and retained in such diverse areas as labor law, human resources, payroll and benefits administration, environmental law, customs law, logistics, import/export operations, accounting, taxation, real estate law, etc. Although there is much involved with the establishment of a wholly owned subsidiary, it does enable the organization to have 100% control over all of its activities.\nShelter Operation.\nA fourth option that allows firms to fully control their own production and quality, to benefit from the experience of an organization that knows the local market, and which eliminates the need to make sizeable investments in physical and human assets is the manufacturing Shelter. Established in 1966, Cal Pacifico S.A. de C.V. was the second company to operate under the then new Maquiladora Program in Mexico and pioneered the shelter service provider model, providing those services to clients in that same year. The model proved so successful that later Cal Pacifico brought to Mexico to manufacture under the shelter operation method a long list of multinational manufacturers such as Asahi Overseas Corp., Bayer Corp., Eli Lilly & Co., 2 divisions of Emerson Electric Co., Esselte Pendaflex Corp., 2 divisions of General Dynamics Corp., Haemonetics Corp., 2 divisions of Hughes Corp., ITT General Controls, Medtronic, Inc., Northrop Grumman Corp., Pall Corp., Polk Audio, Inc., Scott USA, Smith Goggle Co., Sony Corporation of America, 7 divisions of Teledyne, Inc., The Carlyle Group, and Tyco, Inc. among others. Working through a shelter service provider, foreign-based manufacturers are able to initiate operations quickly without actually establishing a legal presence in the country. They are in Mexico as a department or subsidiary of their chosen shelter service provider. In essence, firms opting to use this vehicle are “sheltered” from many of the risks and liabilities that normally affect firms that choose to incorporate directly. Under the typical shelter arrangement, manufacturers send machinery & equipment, raw materials and supervisory personnel to train and manage workers, while the shelter service provider performs the tasks and functions that are not “core” to the manufacturing process. The manufacturer controls those areas that affect profitability and sustained growth. Shelter service providers typically offer their clients services in some or all of the following areas: human resources, payroll and benefits administration, logistics, import/export operations, accounting, taxation, legal, risk management, plant and park management, procurement, environmental, customs compliance, and real estate leasing. Those shelter services provide for the perfect match of offshore operational knowledge and manufacturing expertise... the technical support capabilities of the shelter service provider and the product manufacturing talents of its client(s).\nThis is a value-added outsourcing arrangement in that it gives manufacturers a means by which to greater leverage core competencies and intellectual assets. An organization that does this becomes more nimble, and experiences faster and higher levels of innovation. Additionally this arrangement is attractive to firms seeking to pursue strategies of leveraged growth. As a manufacturer expands under a shelter arrangement, they absorb only a portion of the additional overhead that an expansion of activities requires.\nOutsourcing.\nA quickly growing fifth option for foreign companies to set up manufacturing operations in Mexico is to \"Outsource\" their manufacturing operation to an independent Corporation \"Maquiladora\". The manufacturing outsource option is a hybrid of both the \"shelter\" system and traditional \"contract manufacturing or subcontracting\". The way that the manufacturing outsource option works is that a foreign company essentially hires the maquiladora to manufacture the foreign company's products for them in Mexico (much like in a \"contract manufacturing / subcontract\" situation) but with an inexpensive Mexican workforce that utilizes the equipment, tooling, and processes of the foreign company (much like in a \"shelter\" situation).\nThe key difference between a manufacturing outsource situation and a contract manufacturing / subcontracting situation, is that in a contract manufacturing / subcontracting situation the contract manufacturer / subcontractor already has the equipment, tooling, procedure, supply chain, and expertise in place and is currently manufacturing products that are very similar to the products that the foreign company needs. In contrast, a manufacturing outsource company utilizes the foreign company's equipment, tooling, supply chain, and procedure combined with in-house expertise to manufacture the foreign company's product in exactly the same way the foreign company makes it themselves.\nThe key difference between a manufacturing outsource situation and a \"shelter\" situation, is that in a shelter situation the foreign company must have a constant physical presence in Mexico to manage and oversee their operation, as the shelter provider bills the foreign company for the services provided (see “shelter” above) without taking responsibility for production, quality, and delivery of the product. In contrast, a manufacturing outsource company bills the foreign company on a “price per piece” basis which shifts the responsibility for production, quality, and delivery to the manufacturing outsource company; therefore allowing the foreign company to concentrate on their core competencies without having to manage a foreign manufacturing operation.\nThe manufacturing outsource option is rapidly becoming a reality for many foreign companies interested in utilizing Mexico's cost-effective workforce.", "Engineering,_Manufacturing": 0.9997804761, "qwen": "Yes"}
{"id": "44575211", "revid": "14703151", "url": "https://en.wikipedia.org/wiki?curid=44575211", "title": "Vacuum assisted resin transfer molding", "text": "Vacuum Assisted Resin Transfer Molding (VARTM) or Vacuum Injected Molding (VIM) is a closed mold, out of autoclave (OOA) composite manufacturing process. VARTM is a variation of Resin Transfer Molding (RTM) with its distinguishing characteristic being the replacement of the top portion of a mold tool with a vacuum bag and the use of a vacuum to assist in resin flow. The process involves the use of a vacuum to facilitate resin flow into a fiber layup contained within a mold tool covered by a vacuum bag. After the impregnation occurs the composite part is allowed to cure at room temperature with an optional post cure sometimes carried out.\nProcess.\nTypically, this process uses a low viscosity (100 to 1000 cP) polyester or vinyl ester resin along with fiberglass fibers to create a composite. Normally the process is capable of producing composites with a fiber volume fraction between 40 and 50%. The resin to fiber ratio is important for determining the overall strength and performance of the final part, with mechanical strength being most influenced by the type of fiber reinforcement. The type of resin used will primarily determine the corrosion resistance, heat distortion temperature, and surface finish. Resins used in this process must have low viscosities due to the limited pressure differential provided by the vacuum pump. High performance fibers, such as carbon fiber, can also be used. However, their usage is less common and is mainly for the fabrication of high end parts.\nAir Leakages.\nFor VARTM to create high quality composite parts it is crucial that air leakages are avoided. Air leakages can cause resin to improperly flow through the mold and also lead to the formation of air bubbles. Defects in the form of voids occur when the composite cures with air bubbles inside of it. Air leakage can be caused by a defect in the vacuum bag, an improper application of the sealant tape, or an improper seal at the points where the hose meets the vacuum bag.\nAir leakages can be detected using various methods. In some situations air bubbles, and consequentially air leakages can be detected simply through a visual inspection of the composite. The most simple ‘Leak isolation’ method involves monitoring the vacuum pressure level to determine if there are air leaks. If the vacuum pressure level does not decrease after vacuuming all of the air out of the mold, then it can be determined that there is no air leakages. However, if there was a drop in the vacuum pressure level it would be an indication that there was an air leakage. Unfortunately, this method for identifying the presence of an air leak does not determine the air leak's location.\nSound magnification is also utilized to locate leaks. Since air leaks make noise, this method utilizes a microphone to amplify sound to a set of speakers or headphones to help in the identification of leaks. This allows a user to detect an air leak and use the microphone to help them find the location of the leak. Unfortunately, this method is ineffective in noisy environments.\nHeated air can also be utilized to detect leaks. In this method heated air is forced through the mold prior to the use of a vacuum pump. If there are any air leaks in the process's set up the hot air will be expelled through the leak. An infrared detector, can then be used to determine if there are any heat releases on the surface of vacuum bag, which would be an indication of the presence of an air leak.\nVARTM vs RTM.\nBoth VARTM and RTM are closed mold processes where pressure is used to inject resin into the mold. There are few differences in the materials used in VARTM vs RTM, with the resin and fiber basically being the same for both processes. Therefore, if factors such as fiber to resin ratio and cross-sectional fiber distribution were held constant for each process, the molded part performances would be similar.\nRTM has a fiber preform placed between mold halves, while VARTM uses the bottom part of the mold tool and a vacuum bag with resin flow caused by the use of a vacuum. RTM results in small-medium-sized parts that can also be complex in shape, while VARTM can also create very large parts. VARTM also advantageously has lower equipment costs than RTM. The single sided nature of the VARTM mold has the drawback of only allowing for one side of the composite to have an A-class finish. However, parts can be manufactured with an A-class finish on both sides with RTM due it having both a top and bottom mold.\nAdvantages and Applications.\nThis process offers the benefit of not requiring an expensive autoclave while also being capable of producing large, complex aerospace-grade parts. Products produced using this method vary widely in their application with parts being used in transportation, wind energy, marine, infrastructure, and aerospace applications. The process's ability to create large and complex parts has allowed it to effectively reduce manufacturing costs when utilized to produce parts that are traditionally constructed of numerous small components. For instance, LOCKHEED Martin Space Systems (LMSS) experienced a manufacturing cost saving of up to 75% when it began to produce the quarter section of the equipment bay for the Trident II D5 missile using VARTM.", "Engineering,_Manufacturing": 0.9998069406, "qwen": "Yes"}
{"id": "44578263", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=44578263", "title": "Void (composites)", "text": "A void is a pore that remains unfilled with polymer and fibers in a composite material. Voids are typically the result of poor manufacturing of the material and are generally deemed undesirable. Voids can affect the mechanical properties and lifespan of the composite. They degrade mainly the matrix-dominated properties such as interlaminar shear strength, longitudinal compressive strength, and transverse tensile strength. Voids can act as crack initiation sites as well as allow moisture to penetrate the composite and contribute to the anisotropy of the composite. For aerospace applications, a void content of approximately 1% is still acceptable, while for less sensitive applications, the allowance limit is 3-5%. Although a small increase in void content may not seem to cause significant issues, a 1-3% increase in void content of carbon fiber reinforced composite can reduce the mechanical properties by up to 20% Void content in composites is represented as a ratio, also called void ratio, where the volume of voids, solid material, and bulk volume are taken into account. Void ratio can be calculated by the formula below where e is the void ratio of the composite, Vv is the volume of the voids, and Vt is the volume of the bulk material.\nFormation of Voids.\nVoids are considered defects in composite structures and there are several types of voids that can form in composites depending on the fabrication route and matrix type. Among other factors that can influence the quantity and location of voids are pre-preg impregnation, surface morphology, curing parameters, compaction pressure, fiber bridging, excessive resin bleed, and the thickness of layup .\nA resin with a high viscosity will likely produce voids in a composite. It is difficult for a resin or matrix with a high viscosity to penetrate the original void spaces between adjacent fibers. This will cause voids to form close the fiber surface. Preventing these voids becomes a more daunting task when the fibers are packed tightly together in a composite \nA high void proportion can be obtained in a composite due to errors in processing as well. If the temperature used for curing is too low for the particular matrix used, complete degassing might not occur. However, if the temperature used for curing is too high for a particular matrix, gelation might occur too rapidly and voids may still be present . For example, if a laminate composite is cured at a temperature that is too low for the particular matrix used, the resin viscosity could remain high and hinder removing the void spaces between individual plies Some resins can cure at room temperature while other resins require temperatures up to 200 °C, but curing above or below the required temperature for a particular matrix can increase the amount of voids present in a composite. If the injection pressure in a resin injection pultrusion process is not high enough, the resin or matrix might not be able to penetrate the fiber bed to completely wet out the fibers without voids. Entrapped air or bubbles can be formed in the resin during resin mixing or as a result of mechanical gas entrapment by dual scale fingering in fibrous reinforcements. If these bubbles are not removed before the wetting of the fibers or curing of the composite, the bubbles could become voids that can be found throughout the final composite structure.\nReduction of Voids.\nBecause voids are viewed as defects in composite materials, many methods are applied for reducing voids in composites. Traditionally, using vacuum bagging system and autoclave under pressure and heat will minimize or prevent voids from forming. \nThe vacuum bagging system combined with autoclave is a common method used in industrial processes to achieve a low void content for thermoset composites. Vacuum evacuation is the way reducing exciting amount of voids by physically transporting the voids out of the resin and fiber network through vacuum lines, and it is influenced by the viscosity of resin. Autoclave pressure is used to assist vacuum in removing trapped air and excess resin while at the same time preventing volatiles from coming out of the resin at high temperatures.\nOptimization of injection flow rate is often calculated to minimize voids in Resin Transfer Molded (RTM) or Vacuum Assisted Resin Infusion (VARI) composites. During the injection phase, a liquid resin impregnates the fibers before curing and solidification, often creating voids in the part during the injection. Through an algorithm between fluid flow velocity (v) and the percentages of macro-voids (V1) and micro-voids (V2)\nan optimized rate can be obtained and the voids in RTM and VARI composites can be reduced, thus improving properties of the composite.", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "44597365", "revid": "27799040", "url": "https://en.wikipedia.org/wiki?curid=44597365", "title": "5356 aluminium alloy", "text": "5356 aluminium alloy is an alloy in the wrought aluminium-magnesium family (5000 or 5xxx series). Unlike most aluminium-magnesium alloys, it is primarily used as welding filler. It is one of the most popular aluminium filler alloys, alongside 4043. It possesses relatively high strength, but at the expense of being more vulnerable to cracking. It is the preferred filler when making lap or butt welds on the popular 6061 aluminium alloy, or when the welded parts are to be anodized.", "Engineering,_Manufacturing": 0.9998762608, "qwen": "Yes"}
{"id": "53601", "revid": "25274005", "url": "https://en.wikipedia.org/wiki?curid=53601", "title": "Metal casting", "text": "In metalworking and jewelry making, casting is a process in which a liquid metal is delivered into a mold (usually by a crucible) that contains a negative impression (i.e., a three-dimensional negative image) of the intended shape. The metal is poured into the mold through a hollow channel called a sprue. The metal and mold are then cooled, and the metal part (the \"casting\") is extracted. Casting is most often used for making complex shapes that would be difficult or uneconomical to make by other methods.\nCasting processes have been known for thousands of years, and have been widely used for sculpture (especially in bronze), jewelry in precious metals, and weapons and tools. Highly engineered castings are found in 90 percent of durable goods, including cars, trucks, aerospace, trains, mining and construction equipment, oil wells, appliances, pipes, hydrants, wind turbines, nuclear plants, medical devices, defense products, toys, and more.\nTraditional techniques include lost-wax casting (which may be further divided into centrifugal casting, and vacuum assist direct pour casting), plaster mold casting and sand casting.\nThe modern casting process is subdivided into two main categories: expendable and non-expendable casting. It is further broken down by the mold material, such as sand or metal, and pouring method, such as gravity, vacuum, or low pressure.\nExpendable mold casting.\nExpendable mold casting is a generic classification that includes sand, plastic, shell, plaster, and investment (lost-wax technique) moldings. This method of mold casting involves the use of temporary, non-reusable molds.\nSand casting.\nSand casting is one of the most popular and simplest types of casting, and has been used for centuries. Sand casting allows for smaller batches than permanent mold casting and at a very reasonable cost. Not only does this method allow manufacturers to create products at a low cost, but there are other benefits to sand casting, such as very small-size operations. The process allows for castings small enough fit in the palm of one's hand to those large enough for a train car bed (one casting can create the entire bed for one rail car). Sand casting also allows most metals to be cast depending on the type of sand used for the molds.\nSand casting requires a lead time of days, or even weeks sometimes, for production at high output rates (1–20 pieces/hr-mold) and is unsurpassed for large-part production. Green (moist) sand, which is black in color, has almost no part weight limit, whereas dry sand has a practical part mass limit of . Minimum part weight ranges from . The sand is bonded using clays, chemical binders, or polymerized oils (such as motor oil). Sand can be recycled many times in most operations and requires little maintenance.\nLoam molding.\nLoam molding has been used to produce large symmetrical objects such as cannon and church bells. Loam is a mixture of clay and sand with straw or dung. A model of the produced is formed in a friable material (the chemise). The mold is formed around this chemise by covering it with loam. This is then baked (fired) and the chemise removed. The mold is then stood upright in a pit in front of the furnace for the molten metal to be poured. Afterwards the mold is broken off. Molds can thus only be used once, so that other methods are preferred for most purposes.\nPlaster mold casting.\nPlaster casting is similar to sand casting except that plaster of paris is used instead of sand as a mold material. Generally, the form takes less than a week to prepare, after which a production rate of 1–10 units/hr-mold is achieved, with items as massive as and as small as with very good surface finish and close tolerances. Plaster casting is an inexpensive alternative to other molding processes for complex parts due to the low cost of the plaster and its ability to produce near net shape castings. The biggest disadvantage is that it can only be used with low melting point non-ferrous materials, such as aluminium, copper, magnesium, and zinc.\nShell molding.\nShell molding is similar to sand casting, but the molding cavity is formed by a hardened \"shell\" of sand instead of a flask filled with sand. The sand used is finer than sand casting sand and is mixed with a resin so that it can be heated by the pattern and hardened into a shell around the pattern. Because of the resin and finer sand, it gives a much finer surface finish. The process is easily automated and more precise than sand casting. Common metals that are cast include cast iron, aluminium, magnesium, and copper alloys. This process is ideal for complex items that are small to medium-sized.\nInvestment casting.\nInvestment casting (known as lost-wax casting in art) is a process that has been practiced for thousands of years, with the lost-wax process being one of the oldest known metal forming techniques. From 5000 years ago, when beeswax formed the pattern, to today's high technology waxes, refractory materials, and specialist alloys, the castings ensure high-quality components are produced with the key benefits of accuracy, repeatability, versatility, and integrity.\nInvestment casting derives its name from the fact that the pattern is invested, or surrounded, with a refractory material. The wax patterns require extreme care for they are not strong enough to withstand forces encountered during the mold making. One advantage of investment casting is that the wax can be reused.\nThe process is suitable for repeatable production of net shape components from a variety of different metals and high performance alloys. Although generally used for small castings, this process has been used to produce complete aircraft door frames, with steel castings of up to 300 kg and aluminium castings of up to 30 kg. Compared to other casting processes such as die casting or sand casting, it can be an expensive process. However, the components that can be produced using investment casting can incorporate intricate contours, and in most cases the components are cast near net shape, so require little or no rework once cast.\nWaste molding of plaster.\nA durable plaster intermediate is often used as a stage toward the production of a bronze sculpture or as a pointing guide for the creation of a carved stone. With the completion of a plaster, the work is more durable (if stored indoors) than a clay original which must be kept moist to avoid cracking. With the low cost plaster at hand, the expensive work of bronze casting or stone carving may be deferred until a patron is found, and as such work is considered to be a technical, rather than artistic process, it may even be deferred beyond the lifetime of the artist.\nIn waste molding a simple and thin plaster mold, reinforced by sisal or burlap, is cast over the original clay mixture. When cured, it is then removed from the damp clay, incidentally destroying the fine details in undercuts present in the clay, but which are now captured in the mold. The mold may then at any later time (but only once) be used to cast a plaster positive image, identical to the original clay. The surface of this plaster may be further refined and may be painted and waxed to resemble a finished bronze casting.\nEvaporative-pattern casting.\nThis is a class of casting processes that use pattern materials that evaporate during the pour, which means there is no need to remove the pattern material from the mold before casting. The two main processes are lost-foam casting and full-mold casting.\nLost-foam casting.\nLost-foam casting is a type of evaporative-pattern casting process that is similar to investment casting except foam is used for the pattern instead of wax. This process takes advantage of the low boiling point of foam to simplify the investment casting process by removing the need to melt the wax out of the mold.\nFull-mold casting.\nFull-mold casting is an evaporative-pattern casting process which is a combination of sand casting and lost-foam casting. It uses an expanded polystyrene foam pattern which is then surrounded by sand, much like sand casting. The metal is then poured directly into the mold, which vaporizes the foam upon contact.\nNon-expendable mold casting.\nNon-expendable mold casting differs from expendable processes in that the mold need not be reformed after each production cycle. This technique includes at least four different methods: permanent, die, centrifugal, and continuous casting. This form of casting also results in improved repeatability in parts produced and delivers near net shape results.\nPermanent mold casting.\nPermanent mold casting is a metal casting process that employs reusable molds (\"permanent molds\"), usually made from metal. The most common process uses gravity to fill the mold. However, gas pressure or a vacuum are also used. A variation on the typical gravity casting process, called slush casting, produces hollow castings. Common casting metals are aluminum, magnesium, and copper alloys. Other materials include tin, zinc, and lead alloys and iron and steel are also cast in graphite molds. Permanent molds, while lasting more than one casting still have a limited life before wearing out.\nDie casting.\nThe die casting process forces molten metal under high pressure into mold cavities (which are machined into dies). Most die castings are made from nonferrous metals, specifically zinc, copper, and aluminium-based alloys, but ferrous metal die castings are possible. The die casting method is especially suited for applications where many small to medium-sized parts are needed with good detail, a fine surface quality and dimensional consistency.\nSemi-solid metal casting.\nSemi-solid metal (SSM) casting is a modified die casting process that reduces or eliminates the residual porosity present in most die castings. Rather than using liquid metal as the feed material, SSM casting uses a higher viscosity feed material that is partially solid and partially liquid. A modified die casting machine is used to inject the semi-solid slurry into reusable hardened steel dies. The high viscosity of the semi-solid metal, along with the use of controlled die filling conditions, ensures that the semi-solid metal fills the die in a non-turbulent manner so that harmful porosity can be essentially eliminated.\nUsed commercially mainly for aluminium and magnesium alloys, SSM castings can be heat treated to the T4, T5 or T6 tempers. The combination of heat treatment, fast cooling rates (from using uncoated steel dies) and minimal porosity provides excellent combinations of strength and ductility. Other advantages of SSM casting include the ability to produce complex shaped parts net shape, pressure tightness, tight dimensional tolerances and the ability to cast thin walls.\nCentrifugal casting.\nIn this process molten metal is poured in the mold and allowed to solidify while the mold is rotating. Metal is poured into the center of the mold at its axis of rotation. Due to inertial force, the liquid metal is thrown out toward the periphery.\nCentrifugal casting is both gravity and pressure independent since it creates its own force feed using a temporary sand mold held in a spinning chamber. Lead time varies with the application. Semi- and true-centrifugal processing permit 30–50 pieces/hr-mold to be produced, with a practical limit for batch processing of approximately 9000 kg total mass with a typical per-item limit of 2.3–4.5 kg.\nIndustrially, the centrifugal casting of railway wheels was an early application of the method developed by the German industrial company Krupp and this capability enabled the rapid growth of the enterprise.\nSmall art pieces such as jewelry are often cast by this method using the lost wax process, as the forces enable the rather viscous liquid metals to flow through very small passages and into fine details such as leaves and petals. This effect is similar to the benefits from vacuum casting, also applied to jewelry casting.\nContinuous casting.\nContinuous casting is a refinement of the casting process for the continuous, high-volume production of metal sections with a constant cross-section. It's primarily used to produce a semi-finished products for further processing. Molten metal is poured into an open-ended, water-cooled mold, which allows a 'skin' of solid metal to form over the still-liquid center, gradually solidifying the metal from the outside in. After solidification, the strand, as it is sometimes called, is continuously withdrawn from the mold. Predetermined lengths of the strand can be cut off by either mechanical shears or traveling oxyacetylene torches and transferred to further forming processes, or to a stockpile. Cast sizes can range from strip (a few millimeters thick by about five meters wide) to billets (90 to 160 mm square) to slabs (1.25 m wide by 230 mm thick). Sometimes, the strand may undergo an initial hot rolling process before being cut.\nContinuous casting is used due to the lower costs associated with continuous production of a standard product, and also increased quality of the final product. Metals such as steel, copper, aluminum and lead are continuously cast, with steel being the metal with the greatest tonnages cast using this method.\nUpcasting.\nThe upcasting (up-casting, upstream, or upward casting) is a method of either vertical or horizontal continuous casting of rods and pipes of various profiles (cylindrical, square, hexagonal, slabs etc.) of 8-30mm in diameter. Copper (Cu), bronze (Cu·Sn alloy), nickel alloys are usually used because of greater casting speed (in case of vertical upcasting) and because of better physical features obtained. The advantage of this method is that metals are almost oxygen-free and that the rate of product crystallization (solidification) may be adjusted by in a crystallizer - a high-temperature resistant device that cools a growing metal rod or pipe by using water.\nThe method is comparable to Czochralski method of growing silicon (Si) crystals, which is a metalloid.\nTerminology.\nMetal casting processes uses the following terminology:\nSome specialized processes, such as die casting, use additional terminology.\nTheory.\nCasting is a solidification process, which means the solidification phenomenon controls most of the properties of the casting. Moreover, most of the casting defects occur during solidification, such as \"gas porosity\" and \"solidification shrinkage\".\nSolidification occurs in two steps: \"nucleation\" and \"crystal growth\". In the nucleation stage, solid particles form within the liquid. When these particles form, their internal energy is lower than the surrounded liquid, which creates an energy interface between the two. The formation of the surface at this interface requires energy, so as nucleation occurs, the material actually undercools (i.e. cools below its solidification temperature) because of the extra energy required to form the interface surfaces. It then recalescences, or heats back up to its solidification temperature, for the crystal growth stage. Nucleation occurs on a pre-existing solid surface because not as much energy is required for a partial interface surface as for a complete spherical interface surface. This can be advantageous because fine-grained castings possess better properties than coarse-grained castings. A fine grain structure can be induced by \"grain refinement\" or \"inoculation\", which is the process of adding impurities to induce nucleation.\nAll of the nucleations represent a crystal, which grows as the heat of fusion is extracted from the liquid until there is no liquid left. The direction, rate, and type of growth can be controlled to maximize the properties of the casting. Directional solidification is when the material solidifies at one end and proceeds to solidify to the other end; this is the most ideal type of grain growth because it allows liquid material to compensate for shrinkage.\nCooling curves.\nCooling curves are important in controlling the quality of a casting. The most important part of the cooling curve is the \"cooling rate\" which affects the microstructure and properties. Generally speaking, an area of the casting which is cooled quickly will have a fine grain structure and an area which cools slowly will have a coarse grain structure. Below is an example cooling curve of a pure metal or eutectic alloy, with defining terminology.\nNote that before the thermal arrest the material is a liquid and after it the material is a solid; during the thermal arrest the material is converting from a liquid to a solid. Also, note that the greater the superheat the more time there is for the liquid material to flow into intricate details.\nThe above cooling curve depicts a basic situation with a pure metal, however, most castings are of alloys, which have a cooling curve shaped as shown below.\nNote that there is no longer a thermal arrest, instead there is a freezing range. The freezing range corresponds directly to the liquidus and solidus found on the phase diagram for the specific alloy.\nChvorinov's rule.\nThe local solidification time can be calculated using Chvorinov's rule, which is:\nWhere \"t\" is the solidification time, \"V\" is the volume of the casting, \"A\" is the surface area of the casting that contacts the mold, \"n\" is a constant, and \"B\" is the mold constant. It is most useful in determining if a riser will solidify before the casting, because if the riser does solidify first then it is worthless.\nThe gating system.\nThe gating system serves many purposes, the most important being conveying the liquid material to the mold, but also controlling shrinkage, the speed of the liquid, turbulence, and trapping dross. The gates are usually attached to the thickest part of the casting to assist in controlling shrinkage. In especially large castings multiple gates or runners may be required to introduce metal to more than one point in the mold cavity. The speed of the material is important because if the material is traveling too slowly it can cool before completely filling, leading to misruns and cold shuts. If the material is moving too fast then the liquid material can erode the mold and contaminate the final casting. The shape and length of the gating system can also control how quickly the material cools; short round or square channels minimize heat loss.\nThe gating system may be designed to minimize turbulence, depending on the material being cast. For example, steel, cast iron, and most copper alloys are turbulent insensitive, but aluminium and magnesium alloys are turbulent sensitive. The turbulent insensitive materials usually have a short and open gating system to fill the mold as quickly as possible. However, for turbulent sensitive materials short sprues are used to minimize the distance the material must fall when entering the mold. Rectangular pouring cups and tapered sprues are used to prevent the formation of a vortex as the material flows into the mold; these vortices tend to suck gas and oxides into the mold. A large sprue well is used to dissipate the kinetic energy of the liquid material as it falls down the sprue, decreasing turbulence. The \"choke\", which is the smallest cross-sectional area in the gating system used to control flow, can be placed near the sprue well to slow down and smooth out the flow. Note that on some molds the choke is still placed on the gates to make separation of the part easier, but induces extreme turbulence. The gates are usually attached to the bottom of the casting to minimize turbulence and splashing.\nThe gating system may also be designed to trap dross. One method is to take advantage of the fact that some dross has a lower density than the base material so it floats to the top of the gating system. Therefore, long flat runners with gates that exit from the bottom of the runners can trap dross in the runners; note that long flat runners will cool the material more rapidly than round or square runners. For materials where the dross is a similar density to the base material, such as aluminium, \"runner extensions\" and \"runner wells\" can be advantageous. These take advantage of the fact that the dross is usually located at the beginning of the pour, therefore the runner is extended past the last gate(s) and the contaminates are contained in the wells. Screens or filters may also be used to trap contaminates.\nIt is important to keep the size of the gating system small, because it all must be cut from the casting and remelted to be reused. The efficiency, or \"\", of a casting system can be calculated by dividing the weight of the casting by the weight of the metal poured. Therefore, the higher the number the more efficient the gating system/risers.\nShrinkage.\nThere are three types of shrinkage: \"shrinkage of the liquid\", \"solidification shrinkage\" and \"patternmaker's shrinkage\". The shrinkage of the liquid is rarely a problem because more material is flowing into the mold behind it. Solidification shrinkage occurs because metals are less dense as a liquid than a solid, so during solidification the metal density dramatically increases. Patternmaker's shrinkage refers to the shrinkage that occurs when the material is cooled from the solidification temperature to room temperature, which occurs due to thermal contraction.\nSolidification shrinkage.\nMost materials shrink as they solidify, but, as the adjacent table shows, a few materials do not, such as gray cast iron. For the materials that do shrink upon solidification the type of shrinkage depends on how wide the freezing range is for the material. For materials with a narrow freezing range, less than , a cavity, known as a \"pipe\", forms in the center of the casting, because the outer shell freezes first and progressively solidifies to the center. Pure and eutectic metals usually have narrow solidification ranges. These materials tend to form a \"skin\" in open air molds, therefore they are known as \"skin forming alloys\". For materials with a wide freezing range, greater than , much more of the casting occupies the \"mushy\" or \"slushy\" zone (the temperature range between the solidus and the liquidus), which leads to small pockets of liquid trapped throughout and ultimately porosity. These castings tend to have poor ductility, toughness, and fatigue resistance. Moreover, for these types of materials to be fluid-tight, a secondary operation is required to impregnate the casting with a lower melting point metal or resin.\nFor the materials that have narrow solidification ranges, pipes can be overcome by designing the casting to promote directional solidification, which means the casting freezes first at the point farthest from the gate, then progressively solidifies toward the gate. This allows a continuous feed of liquid material to be present at the point of solidification to compensate for the shrinkage. Note that there is still a shrinkage void where the final material solidifies, but if designed properly, this will be in the gating system or riser.\nRisers and riser aids.\nRisers, also known as \"feeders\", are the most common way of providing directional solidification. It supplies liquid metal to the solidifying casting to compensate for solidification shrinkage. For a riser to work properly the riser must solidify after the casting, otherwise it cannot supply liquid metal to shrinkage within the casting. Risers add cost to the casting because it lowers the \"yield\" of each casting; i.e. more metal is lost as scrap for each casting. Another way to promote directional solidification is by adding chills to the mold. A chill is any material which will conduct heat away from the casting more rapidly than the material used for molding.\nRisers are classified by three criteria. The first is if the riser is open to the atmosphere, if it is then it is called an \"open\" riser, otherwise it is known as a \"blind\" type. The second criterion is where the riser is located; if it is located on the casting then it is known as a \"top riser\" and if it is located next to the casting it is known as a \"side riser\". Finally, if the riser is located on the gating system so that it fills after the molding cavity, it is known as a \"live riser\" or \"hot riser\", but if the riser fills with materials that have already flowed through the molding cavity it is known as a \"dead riser\" or \"cold riser\".\nRiser aids are items used to assist risers in creating directional solidification or reducing the number of risers required. One of these items are \"chills\" which accelerate cooling in a certain part of the mold. There are two types: external and internal chills. External chills are masses of high-heat-capacity and high-thermal-conductivity material that are placed on an edge of the molding cavity. Internal chills are pieces of the same metal that is being poured, which are placed inside the mold cavity and become part of the casting. Insulating sleeves and toppings may also be installed around the riser cavity to slow the solidification of the riser. Heater coils may also be installed around or above the riser cavity to slow solidification.\nPatternmaker's shrink.\nShrinkage after solidification can be dealt with by using an oversized pattern designed specifically for the alloy used. \"s\", or \"s\", are used to make the patterns oversized to compensate for this type of shrinkage. These rulers are up to 2.5% oversize, depending on the material being cast. These rulers are mainly referred to by their percentage change. A pattern made to match an existing part would be made as follows: First, the existing part would be measured using a standard ruler, then when constructing the pattern, the pattern maker would use a contraction rule, ensuring that the casting would contract to the correct size.\nNote that patternmaker's shrinkage does not take phase change transformations into account. For example, eutectic reactions, martensitic reactions, and graphitization can cause expansions or contractions.\nMold cavity.\nThe mold cavity of a casting does not reflect the exact dimensions of the finished part due to a number of reasons. These modifications to the mold cavity are known as \"allowances\" and account for patternmaker's shrinkage, draft, machining, and distortion. In non-expendable processes, these allowances are imparted directly into the permanent mold, but in expendable mold processes they are imparted into the patterns, which later form the mold cavity. Note that for non-expendable molds an allowance is required for the dimensional change of the mold due to heating to operating temperatures.\nFor surfaces of the casting that are perpendicular to the parting line of the mold a draft must be included. This is so that the casting can be released in non-expendable processes or the pattern can be released from the mold without destroying the mold in expendable processes. The required draft angle depends on the size and shape of the feature, the depth of the mold cavity, how the part or pattern is being removed from the mold, the pattern or part material, the mold material, and the process type. Usually the draft is not less than 1%.\nThe machining allowance varies drastically from one process to another. Sand castings generally have a rough surface finish, therefore need a greater machining allowance, whereas die casting has a very fine surface finish, which may not need any machining tolerance. Also, the draft may provide enough of a machining allowance to begin with.\nThe distortion allowance is only necessary for certain geometries. For instance, U-shaped castings will tend to distort with the legs splaying outward, because the base of the shape can contract while the legs are constrained by the mold. This can be overcome by designing the mold cavity to slope the leg inward to begin with. Also, long horizontal sections tend to sag in the middle if ribs are not incorporated, so a distortion allowance may be required.\nCores may be used in expendable mold processes to produce internal features. The core can be of metal but it is usually done in sand.\nFilling.\nThere are a few common methods for filling the mold cavity: \"gravity\", \"low-pressure\", \"high-pressure\", and \"vacuum\".\nVacuum filling, also known as \"counter-gravity\" filling, is more metal efficient than gravity pouring because less material solidifies in the gating system. Gravity pouring only has a 15 to 50% metal yield as compared to 60 to 95% for vacuum pouring. There is also less turbulence, so the gating system can be simplified since it does not have to control turbulence. Plus, because the metal is drawn from below the top of the pool the metal is free from dross and slag, as these are lower density (lighter) and float to the top of the pool. The pressure differential helps the metal flow into every intricacy of the mold. Finally, lower temperatures can be used, which improves the grain structure. The first patented vacuum casting machine and process dates to 1879.\nLow-pressure filling uses 5 to 15 psig (35 to 100 kPag) of air pressure to force liquid metal up a feed tube into the mold cavity. This eliminates turbulence found in gravity casting and increases density, repeatability, tolerances, and grain uniformity. After the casting has solidified the pressure is released and any remaining liquid returns to the crucible, which increases yield.\nTilt filling.\n\"Tilt filling\", also known as \"tilt casting\", is an uncommon filling technique where the crucible is attached to the gating system and both are slowly rotated so that the metal enters the mold cavity with little turbulence. The goal is to reduce porosity and inclusions by limiting turbulence. For most uses tilt filling is not feasible because the following inherent problem: if the system is rotated slow enough to not induce turbulence, the front of the metal stream begins to solidify, which results in mis-runs. If the system is rotated faster it induces turbulence, which defeats the purpose. Durville of France was the first to try tilt casting, in the 1800s. He tried to use it to reduce surface defects when casting coinage from aluminium bronze.\nMacrostructure.\nThe grain macrostructure in ingots and most castings have three distinct regions or zones: the chill zone, columnar zone, and equiaxed zone. The image below depicts these zones.\nThe chill zone is named so because it occurs at the walls of the mold where the wall \"chills\" the material. Here is where the nucleation phase of the solidification process takes place. As more heat is removed the grains grow towards the center of the casting. These are thin, long \"columns\" that are perpendicular to the casting surface, which are undesirable because they have anisotropic properties. Finally, in the center the equiaxed zone contains spherical, randomly oriented crystals. These are desirable because they have isotropic properties. The creation of this zone can be promoted by using a low pouring temperature, alloy inclusions, or inoculants.\nInspection.\nCommon inspection methods for steel castings are \"magnetic particle testing\" and \"liquid penetrant testing\". Common inspection methods for aluminum castings are \"radiography\", \"ultrasonic testing\", and \"liquid penetrant testing\".\nDefects.\nThere are a number of problems that can be encountered during the casting process. The main types are: \"gas porosity\", \"shrinkage defects\", \"mold material defects\", \"pouring metal defects\", and \"metallurgical defects\".\nCasting process simulation.\nCasting process simulation uses numerical methods to calculate cast component quality considering mold filling, solidification and cooling, and provides a quantitative prediction of casting mechanical properties, thermal stresses and distortion. Simulation accurately describes a cast component's quality up-front before production starts. The casting rigging can be designed with respect to the required component properties. This has benefits beyond a reduction in pre-production sampling, as the precise layout of the complete casting system also leads to energy, material, and tooling savings.\nThe software supports the user in component design, the determination of melting practice and casting methoding through to pattern and mold making, heat treatment, and finishing. This saves costs along the entire casting manufacturing route.\nCasting process simulation was initially developed at universities starting from the early '70s, mainly in Europe and in the U.S., and is regarded as the most important innovation in casting technology over the last 50 years. Since the late '80s, commercial programs are available which make it possible for foundries to gain new insight into what is happening inside the mold or die during the casting process.", "Engineering,_Manufacturing": 0.9999222755, "qwen": "Yes"}
{"id": "25810137", "revid": "45669535", "url": "https://en.wikipedia.org/wiki?curid=25810137", "title": "Dymalloy", "text": "Dymalloy is a metal matrix composite consisting of 20% copper and 80% silver alloy matrix with type I diamond. It has very high thermal conductivity of 420 W/(m·K), and its thermal expansion can be adjusted to match other materials, e.g. silicon and gallium arsenide chips. It is chiefly used in microelectronics as substrate for high power and high density multi-chip modules, where it aids with removal of waste heat.\nDymalloy was developed as part of CRADA between Sun Microsystems and Lawrence Livermore National Laboratory. It was first researched for use in space-based electronics for the Brilliant Pebbles project.\nDymalloy is prepared from diamond powder of about 25 micrometers size. The grains are coated by physical vapor deposition with 10 nanometers thick layer of alloy of tungsten with 26% rhenium, forming a tungsten carbide layer that assists bonding, then coated with 100 nanometers of copper to avoid carbide oxidation, then compacted in a mold and infiltrated with molten copper-silver alloy. Adding 55 vol.% of diamond yields material with thermal expansion matching that of gallium arsenide; slightly higher amount of diamond allows matching to silicon. Copper can be used instead of copper-silver alloy, but the higher melting point may cause partial transformation of diamond to graphite. The material shows some plasticity. High mechanical strain causes brittle failure in the diamond grains, and ductile failure in the matrix. The diamond grains give the alloy a degree of surface texture; when a smooth surface is desired, the alloy can be plated and polished.\nIn 1996, the price for a 10×10×0.1 cm substrate was quoted as USD 200.\nSimilar alloys are possible with the metal phase consisting of one or more of silver, copper, gold, aluminium, magnesium, and zinc. The carbide-forming metal can be selected from titanium, zirconium, hafnium, vanadium, niobium, tantalum, and chromium, where Ti, Zr, and Hf are preferable. The amount of carbide-forming metal must be sufficient to coat at least 25% of the diamond grains, as otherwise, the bonding is insufficient, the heat transfer between matrix and diamond grains is weak which leads to loss of effectivity towards the level of the matrix metal alone, and the material may deform at higher temperatures, and must be low in order to prevent formation of too thick carbide layer that would hinder heat transfer. The volume of diamond should be higher than 30 vol.%, as lower ratio does not provide significant increase of thermal conductivity, and lower than 70 vol.% as higher ratio of diamond makes thermal expansion matching to semiconductors difficult. The grains should also be completely surrounded with metal, to avoid deformation due to different thermal expansion coefficients between diamond and metal; the carbide coating assists with this.\nA similar material is AlSiC, with aluminium instead of copper-silver alloy and silicon carbide instead of diamond.", "Engineering,_Manufacturing": 0.9999921322, "qwen": "Yes"}
{"id": "25814044", "revid": "29463730", "url": "https://en.wikipedia.org/wiki?curid=25814044", "title": "Pipe Cutting", "text": "Pipe cutting, or pipe profiling, is a mechanized industrial process that removes material from pipe or tube to create a desired profile. Typical profiles include straight cuts, mitres, saddles and midsection holes. These complex cuts are usually required to allow a tight fit between two parts that are to be joined via arc welding.\nHot cutting.\nHot cutting is performed by means of a thermal torch (plasma or oxyfuel) and is mounted to the last axis of a multi-axis machine. The axes of the multi-axis machine are powered by electric motors and are synchronized to create a path for the torch and pipe that yield a desired profile. The synchronization of axes is accomplished either mechanically, via cams, levers and gears, or electronically, via microprocessors and controllers.\nCold cutting.\nWhere the high temperatures and sources of ignition required by hot cutting are not desirable, air- or hydraulically-powered pipe cutting machines are used. These comprise a clamshell or chain-mounted cutting head holding a tool steel and feed mechanism which advances the tool a set amount per revolution round the pipe. Tools may be styled to cut and/or prepare the bevel for welding in a single or multiple passes.\nPopular in offshore, pipe processing, ship building, pressure vessel, structural and mechanical contracting manufacturing because of the complex cuts and profiles typical required in their respective industries. Some common pipe cutting applications are: pipe work, offshore jackets, industrial steel structures, stadiums, cranes, nozzles, and pipe laying stingers.", "Engineering,_Manufacturing": 1.0000069141, "qwen": "Yes"}
{"id": "25818098", "revid": "4173550", "url": "https://en.wikipedia.org/wiki?curid=25818098", "title": "Corrugated box design", "text": "Corrugated box design is the process of matching design factors for corrugated fiberboard (sometimes called corrugated cardboard) boxes with the functional physical, processing and end-use requirements. Packaging engineers work to meet the performance requirements of a box while controlling total costs throughout the system. Corrugated boxes are shipping containers used for transport packaging and have important functional and economic considerations.\nIn addition to the structural design discussed in this article, printed bar codes, labels, and graphic design are also vital.\nFunctions.\nCorrugated boxes are used frequently as shipping containers. Boxes need to contain the product from manufacturing through distribution to sale and sometimes end-use. Boxes provide some measure of product protection by themselves but often require inner components such as cushioning, bracing and blocking to help protect fragile contents. The shipping hazards depend largely upon the particular logistics system being employed. For example, boxes unitized into a unit load on a pallet do not encounter individual handling while boxes sorted and shipped through part of their distribution cycle as mixed loads or express carriers can receive severe shocks, kicks, and so forth.\nOrdinary shipping containers require printing and labels to identify the contents, provide legal and regulatory information, and bar codes for routing. Boxes that are used for marketing, merchandising and point-of-sale often have high graphics to help communicate the contents. Some boxes are designed for the display of contents on the shelf known as \"Retail Ready Packaging\". Others are designed to help dispense the contents. Popular for their strength, durability, lightness, recyclability, and cost-effectiveness, corrugated boxes are used for the shipping of a variety of items. Due to the quality and safety of packaging items in corrugated boxes, they are used widely in the food industry. The boxes handle the pressure that comes with stacking, making them ideal for easy transporting.\nMore than 95% of all products in the United States are shipped in corrugated boxes. Corrugated paperboard accounts for more than half of all the paper recycled in the US.\nStacking strength.\nOne of the important functions of a corrugated box is to provide crush resistance (product protection) and adequate strength for stacking in warehouses. If long-term storage of corrugated boxes in high humidity is expected, extra strength and moisture resistance is called for. The method of loading boxes on pallets strongly affects stacking. Vertical columns provide the best box performance while interlocking patterns of boxes significantly reduce performance. The interaction of the boxes and pallets is also important.\nA box can be designed by optimizing the grade of corrugated board, box design, flute direction, and inner supports. Support from the product also provides \"load sharing\" and can be an important factor. Box closures sometimes can have effects on box stacking strength.\nA box can be designed by optimizing the grade of corrugated board, box design, flute direction, and inner supports. Support from the product also provides \"load sharing\" and can be an important factor. Box closures sometimes can have effects on box stacking strength.\nBox compression testing is a means of evaluating boxes, stacks of boxes, and unit loads under controlled conditions. Field conditions of stacking and dynamic compression do not have the same degree of control. Compression strength can be estimated based on container construction, size, and use parameters: actual package testing is often conducted to verify these estimates.\nA box can be designed by optimizing the grade of corrugated board, box design, flute direction, and inner supports. Support from the product also provides \"load sharing\" and can be an important factor. Box closures sometimes can have effects on box stacking strength.\nHandling strength.\nMany items are shipped individually (in part or entirely) by express carrier, mail, or other mixed logistics systems. The demands of multiple manual handlings, automated sortation, and uncontrolled stacking in trucks or air containers put severe stress on boxes, box closures, and the contents. Boxes designed for unit load handling and storage may not be suited to mixed logistics systems. Less than truckload shipping puts more stress on corrugated shipping containers than shipment by uniform pallet loads in trucks or intermodal containers. Boxes sometimes need to be heavier construction to match the needs of the distribution system. Package testing is often matched to the expected shipping hazards. ASTM International and the International Safe Transit Association test protocols reflect this.\nOther factors.\nSeveral texts offer guidance on the box design process. The Wiley Handbook of Packaging Technology offers guidance on considerations and options. ASTM D5639 Standard Practice for Selection of Corrugated Fiberboard Materials and Box Construction Based on Performance Requirements discusses material choices and box structures which may be good options for specified package performance.\nDepending on the contents, some corrugated boxes need extra stiffness or a heavier grade of board. Boxes with hand holes or handles sometimes need higher strength board, reinforcement attached with adhesives, or embedded fibers.\nProcess.\nPackaging engineers design corrugated boxes to meet the particular needs of the product being shipped, the hazards of the shipping environment, (shock, vibration, compression, moisture, etc.), and the needs of retailers and consumers. Engineers and designers start with the needs of the particular project: cost constraints, machinery capabilities, product characteristics, logistics needs, applicable regulations, consumer needs, etc. Often designs are made with Computer Aided Design programs connected to automated sample making tables. Several design and construction options might be considered.Samples are often submitted to package testing based on ASTM or other standard test protocols such as the International Safe Transit Association. Structural design is matched with graphic design. For consumer based designs, marketing personnel sometimes use Focus groups or more quantitative means of assessing acceptance. Test markets are employed for major programs.\nThe process starts by making corrugated board on a corrugating line, a long series of linked machines which may be the size of an (American) football field. A finished piece of single-wall corrugated board is a single corrugated layer sandwiched between two liners.\nSkilled workers prepare job tickets for each stack of box blanks and route the blanks to fabrication machines. Printing dies and patterns are prepared on large, flexible, rubber or tin sheets. They are loaded onto rollers and the box blanks are fed through it, where each is trimmed, printed, cut, scored, folded, and glued to form a box. Finished boxes are then stacked and sent to a banding machine to be wrapped and shipped.\nDesign.\nThe most common box style is the Regular Slotted Container (RSC). All flaps are the same length from score to edge. Typically the major flaps meet in the middle and the minor flaps do not, unless the width is equal to the length. The size of a box can be measured for either internal (for product fit) or external (for handling machinery or palletizing) dimensions. The manufacturer's joint is most often joined with adhesive but may also be taped or stitched. The box is shipped flat (knocked down) to the packager who sets up the box, fills it, and closes it for shipment. Box closure may be by tape, adhesive, staples, strapping, etc.\nBoxes are usually specified and ordered by the internal dimensions.Box styles in Europe are typically specified by a 4-digit code provided by the European Federation of Corrugated Board Manufacturers (FEFCO); an RSC is coded 0201.\nMany other styles of corrugated boxes and structures are available. One common source is the Fibre Box Association:\nRetail display.\nRetailers often ask for merchandise to be delivered to them in shipping containers which allow the easy stocking of full caseloads. The goal is to put the case directly onto shelves and stocking locations without individually handling the unit packs or primary packages. Retailers often require products to come in shelf-ready packaging to reduce stocking costs and save labor expenses.\nSeveral specialized box designs are available.\nGovernment, military, and export.\nMany items being supplied to governments are handled very well: boxes are unitized, shipped on covered trucks or intermodal containers, and storage is in warehouses. Normal \"domestic boxes\" and commercial packaging are acceptable.\nMilitary materiel, field supplies, and humanitarian aid often encounter severe handling and uncontrolled storage. Special box specifications for government shipments are often applicable. Weather-resistant fiberboards, box construction, box closure, and unitizing are needed.\nDangerous and hazardous goods.\nShipment of dangerous goods or hazardous materials are highly regulated. Based on the UN Recommendations on the Transport of Dangerous Goods model regulations, each country has coordinated design and performance requirements for shipment. For example, in the US, the Department of Transportation has jurisdiction and published requirements in Title 49 of the Code of Federal Regulations. Corrugated boxes are described in 4G requirements. Performance (severe drop test, etc.) needs to be certified for the box and contents.\nSome carriers have additional requirements.\nBox closure.\nThe means of closing a box is an important aspect of design. It is affected by the types of equipment available to production lines, the measured laboratory performance, the field performance, and the ability of end-users to easily and safely open the box.\nBox closures include:", "Engineering,_Manufacturing": 1.0000042915, "qwen": "Yes"}
{"id": "25826379", "revid": "37812451", "url": "https://en.wikipedia.org/wiki?curid=25826379", "title": "Central Institute of Tool Design", "text": "Central Institute of Tool Design or CITD is an institute in India providing programs in Tool Engineering and Technology . The CITD main campus is in Hyderabad, Telangana, with a branch campus in Vijayawada and an extension centre in Chennai.\nHistory.\nThe institute was established in 1968 by the government of India with the assistance of United Nations Development Programme (UNDP) and the International Labour Organization (ILO) as an executing agency.\nObjective.\nThe objective of CITD is to meet the requirements of industry in the fields of tool design and manufacture and to train technical personnel in these fields. The institute has strong links with industries to impart practical knowledge by way of undertaking tooling assignments.\nFunctions.\n1) to provide consultancy and advisory services including assistance in the design and development of tools.\n2) to recommend measures to standardise tools, and tooling elements, components of jigs, fixtures, dies etc.\n3) to provide skill development in cutting edge technologies like CAD/CAM, AI, Electronics, Pneumatic, civil.\nFacilities.\nThe Central Institute of Tool Design has a tool room with sophisticated CNC machines like CNC EDM (Charmilles Roboform 54), CNC Wirecut EDM (AGIE Cut Classic-III & Electronics), 4- and 5-Axis High-Speed Machining Centres, Kellenberger CNC Cylindrical Grinding Machine and 3D Coordinate measuring machine with scanning and digitization facilities. The institute is equipped with EMCO table top CNC turning and milling machines with closed loop systems to impart training in CNC Programming.\nThe calibration laboratory has Universal Horizontal metroscope ULM OPAL 600 Carl Zeiss Technology (Germany) and Slip Gauge Measuring Unit 826 with Millitron 1240 (Mahr, Germany) to calibrate limit gauges, micrometers, dial indicators, etc. The Automation Centre is equipped with simulator training kits like Advanced Pneumatics Trainer, Advanced Electro Pneumatics Trainer with PID controls, Advanced Hydraulics Trainer, Advanced Electro Hydraulics Trainer, Closed-loop Hydraulics Trainer with PID Controls, PLC Trainer, Sensors Technology Trainer, Modular Production System with testing, processing, handling and sorting stations, cut section models of elements, transparent working models of hydraulics element etc.\nThe CAD/CAM Centre is equipped with hardware like Compaq workstations, IBM, DELL systems, Pentium IV systems and software like AutoCAD, MDT Ideas NX11, Pro-E Wildfire, Catia V5, UG, Ansys, Nastran, Hypermesh, MasterCam, DelCam, SolidWork, Solid edge, etc.\nCITD has a library with a collection of technical books in tool engineering. IT subscribes to international journals like \"CIRP Annals\", \"American Machinist\", \"Journal of Engineering Materials & Technology\" (ASME), \"Precision Engineering\" (Japan), \"Precision Tool Maker\", etc. For the dissemination of information, the centre publishes a computerised current awareness abstracting bulletin and provides a technical enquiry service. The institute extends its services to developing countries by imparting knowledge and skills to their personnel in the field of Tool Design, CAD/CAM and Low-Cost Automation Techniques.\nActivities.\nCITD conducts regular and part-time training programmes in the field of Tool Design & Manufacture, Low Cost Automation, Mechatronics and Computer Aided Design & Computer Aided Manufacture. It conducts short-term courses, special-purpose clinics in Tool Engineering, seminars, tailor-made programmes, in disciplines for the benefit of working personnel.\nCITD provides a consultancy and servicing facility to industry, including assistance in design and development of tools, and it also recommends measures to standardise tools and tooling elements, components of jigs and fixtures, dies and moulds and other tools. CITD is a member on technical committees of the Bureau of Indian Standards.", "Engineering,_Manufacturing": 1.0000050068, "qwen": "Yes"}
{"id": "9014911", "revid": "1170956115", "url": "https://en.wikipedia.org/wiki?curid=9014911", "title": "Bridgeport (machine tool brand)", "text": "Bridgeport is a brand of milling machine and machining center produced by Bridgeport Machines, Inc. from 1938 until 2004, when it was then acquired by the machine tool conglomerate Hardinge, Inc. \nHistory.\nThe original corporation was founded in Bridgeport, Connecticut, and started selling its machines in 1938. It became known in the following decades for small and medium-sized vertical milling machines, with a form of quill equipped multiple-speed vertical milling head with a ram-on-turret mounting over a knee-and-column base. The American Precision Museum's biography of Rudolph Bannow reports that he conceived the design in 1936 as the logical machine on which to mount the milling head already being built by the Bridgeport Pattern and Model Works (which he owned with a partner Magnus Wahlstrom). The first Bridgeport milling machine (serial number 1) is on display at the Museum.\nDue to the overall success of the company's milling machines, the term \"Bridgeport\" is often used to refer to \"any\" vertical milling machine of the same configuration, regardless of make. Many other companies have cloned the form. Today, the Bridgeport brand still produces this configuration in both manual and computer numerical control (CNC) versions, and such machining centers are now equally as prominent as their manual counterparts.\nBridgeport manual milling machines have come in many types and sizes over the years, including (but not limited to) the C head (original), R head (heavy duty C head), M head, J head (and high speed, 5440 RPM version), 2J1 1/2 head (1.5 HP Vari-Speed), 2J2 (2HP Vari-speed), and Series II head (4HP Vari-speed). All of the heads offer variable speeds, the earlier ones via a step pulley (cone pulley) and the later ones via either continuously variable transmission (CVT) systems or variable-speed drive. Typical table sizes are 9″ × 49″ (Y and X, respectively) and 10″ × 54″. Machine tapers for tool holding include Morse tapers (on early models) and the R8 taper (a widely used standard that Bridgeport created) on most models. Both Morse and R8 allow for both collets and solid holders, and a drill chuck can be held by either of the latter. Machine slides are of the dovetail type, and rotary bearings are mostly of the roller and ball types.", "Engineering,_Manufacturing": 1.0000011921, "qwen": "Yes"}
{"id": "9017656", "revid": "1166235485", "url": "https://en.wikipedia.org/wiki?curid=9017656", "title": "Industrial management", "text": "Industrial management is a branch of engineering which facilitates creation of management system and integrates the diverse engineering processes. Industrial Management deals with industrial design, construction, management, and application of science and engineering principles to improve the entire industrial infrastructure and industrial processes.\nIndustrial Management focuses on the management of industrial processes. Industrial Managers can be said to be responsible for proper and the most efficient interaction of 4Ms: Man, Material, Machine and Method (which every organization needs).\nIndustrial management also involves studying the performance of machines as well as people. Specialists are employed to keep machines in good working condition and to ensure the quality of their production. The flow of materials through the plant is supervised to ensure that neither workers nor machines are idle. Constant inspection is made to keep output up to standard.\nAs a part of engineering and particularly related to the manufacturing engineering industry, studies the structure and organization of industrial companies. It comprises those fields of industrial issues that are necessary for the success of companies within the manufacturing sector.\nWho is an Industrial Manager?\nAn Industrial Manager incorporates the principles of manufacturing system, logistics, supply chain management, materials management, entrepreneurship, among other things. Industrial Managers plan how to efficiently and economically use resources in a business including labor, materials, machines, time, capital, energy, and information. An Industrial Manager also has to deal with creating new systems to solve problems related to waste and inefficiency associated with a business/ industrial process. This field is ever in need of competent personnel capable of applying logic and reasoning to identify strengths and weaknesses of alternative solutions, conclusions, or approaches to such problems. A Masters in Industrial Management specially provides the students a broad-based knowledge and skills required for industrial needs.\nTerm industrial company.\nThe term industrial company is generally applied to a manufacturing firm that – contrary to a crafts business – produces consumer durables in factories from raw materials in mass and serial production (a division of labor) using modern manufacturing machines.\nHistory of industrial management.\nhttps://www.infoplease.com/encyclopedia/social-science/economy/concepts/industrial-management/the-development-of-industrial-management\nCourses of study.\nStudy programs in industrial management are very popular in economies with a high value of manufacturing output, such as the United States and Germany. Especially German research universities incorporate a large number of advanced courses in engineering in their graduate program in industrial management and are, thus, more like M.Eng.- programs. Degree programs are also offered under the title \"industrial administration\".\nSpecialization in Industrial Management.\nSpecialization in Industrial Management is designed to address and solve real life problems relating to industrial set-ups. Collaboration with relevant industries and financial institutes is its modus operandi. This specialization is one of the very few aimed at mid-career professionals who wish to make the move to senior management within industrial and manufacturing organizations. It is designed to provide the business expertise essential for all senior managers by integrating specific engineering subjects with the management of technology and manufacturing systems. The specialization also examines the latest business thinking and provides expert knowledge on engineering and technology issues and theories. Topics such as finance, marketing, management strategy are integrated with modern industrial issues such as project and quality management, manufacturing effectiveness, advanced manufacturing technology and supply chain management.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "669733", "revid": "40683745", "url": "https://en.wikipedia.org/wiki?curid=669733", "title": "Die casting", "text": "Die casting is a metal casting process that is characterized by forcing molten metal under high pressure into a mold cavity. The mold cavity is created using two hardened tool steel dies which have been machined into shape and work similarly to an injection mold during the process. Most die castings are made from non-ferrous metals, specifically zinc, copper, aluminium, magnesium, lead, pewter, and tin-based alloys. Depending on the type of metal being cast, a hot- or cold-chamber machine is used.\nThe casting equipment and the metal dies represent large capital costs and this tends to limit the process to high-volume production. Manufacture of parts using die casting is relatively simple, involving only four main steps, which keeps the incremental cost per item low. It is especially suited for a large quantity of small- to medium-sized castings, which is why die casting produces more castings than any other casting process. Die castings are characterized by a very good surface finish (by casting standards) and dimensional consistency.\nHistory.\nDie casting equipment was invented in 1838 for the purpose of producing movable type for the printing industry. The first die casting-related patent was granted in 1849 for a small hand-operated machine for the purpose of mechanized printing type production. In 1885 Ottmar Mergenthaler invented the Linotype machine, which cast an entire line of type as a single unit, using a die casting process. It nearly completely replaced setting type by hand in the publishing industry. The Soss die-casting machine, manufactured in Brooklyn, NY, was the first machine to be sold in the open market in North America. Other applications grew rapidly, with die casting facilitating the growth of consumer goods, and appliances, by greatly reducing the production cost of intricate parts in high volumes. In 1966, General Motors released the \"Acurad\" process.\nCast metal.\nThe main die casting alloys are: zinc, aluminium, magnesium, copper, lead, and tin; although uncommon, ferrous die casting is also possible. Specific die casting alloys include: zinc aluminium; aluminium to, e.g. The Aluminum Association (AA) standards: AA 380, AA 384, AA 386, AA 390; and AZ91D magnesium. The following is a summary of the advantages of each alloy:\n, maximum weight limits for aluminium, brass, magnesium, and zinc castings are estimated at approximately , and , respectively. By late-2019, press machines capable of die casting single pieces over- were being used to produce aluminium chassis components for cars.\nThe material used defines the minimum section thickness and minimum draft required for a casting as outlined in the table below. The thickest section should be less than , but can be greater.\nDesign geometry.\nThere are a number of geometric features to be considered when creating a parametric model of a die casting:\nEquipment.\nThere are two basic types of die casting machines: \"hot-chamber machines\" and \"cold-chamber machines\". These are rated by how much clamping force they can apply. Typical ratings are between .\nHot-chamber die casting.\nHot-chamber die casting, also known as \"gooseneck machines\", rely upon a pool of molten metal to feed the die. At the beginning of the cycle the piston of the machine is retracted, which allows the molten metal to fill the \"gooseneck\". The pneumatic- or hydraulic-powered piston then forces this metal out of the gooseneck into the die. The advantages of this system include fast cycle times (approximately 15 cycles a minute) and the convenience of melting the metal in the casting machine. The disadvantages of this system are that it is limited to use with low-melting point metals and that aluminium cannot be used because it picks up some of the iron while in the molten pool. Therefore, hot-chamber machines are primarily used with zinc-, tin-, and lead-based alloys.\nCold-chamber die casting.\nThese are used when the casting alloy cannot be used in hot-chamber machines; these include aluminium, zinc alloys with a large composition of aluminium, magnesium and copper. The process for these machines start with melting the metal in a separate furnace. Then a precise amount of molten metal is transported to the cold-chamber machine where it is fed into an unheated shot chamber (or injection cylinder). This shot is then driven into the die by a hydraulic or mechanical piston. The biggest disadvantage of this system is the slower cycle time due to the need to transfer the molten metal from the furnace to the cold-chamber machine.\nMold or tooling.\nTwo dies are used in die casting; one is called the \"cover die half\" and the other the \"ejector die half\". Where they meet is called the parting line. The cover die contains the sprue (for hot-chamber machines) or shot hole (for cold-chamber machines), which allows the molten metal to flow into the dies; this feature matches up with the injector nozzle on the hot-chamber machines or the shot chamber in the cold-chamber machines. The ejector die contains the ejector pins and usually the runner, which is the path from the sprue or shot hole to the mould cavity. The cover die is secured to the stationary, or front, platen of the casting machine, while the ejector die is attached to the movable platen. The mould cavity is cut into two \"cavity inserts\", which are separate pieces that can be replaced relatively easily and bolt into the die halves.\nThe dies are designed so that the finished casting will slide off the cover half of the die and stay in the ejector half as the dies are opened. This assures that the casting will be ejected every cycle because the ejector half contains the \"ejector pins\" to push the casting out of that die half. The ejector pins are driven by an \"ejector pin plate\", which accurately drives all of the pins at the same time and with the same force, so that the casting is not damaged. The ejector pin plate also retracts the pins after ejecting the casting to prepare for the next shot. There must be enough ejector pins to keep the overall force on each pin low, because the casting is still hot and can be damaged by excessive force. The pins still leave a mark, so they must be located in places where these marks will not hamper the casting's purpose.\nOther die components include \"cores\" and \"slides\". Cores are components that usually produce holes or opening, but they can be used to create other details as well. There are three types of cores: fixed, movable, and loose. Fixed cores are ones that are oriented parallel to the pull direction of the dies (i.e. the direction the dies open), therefore they are fixed, or permanently attached to the die. Movable cores are ones that are oriented in any other way than parallel to the pull direction. These cores must be removed from the die cavity after the shot solidifies, but before the dies open, using a separate mechanism. Slides are similar to movable cores, except they are used to form undercut surfaces. The use of movable cores and slides greatly increases the cost of the dies. Loose cores, also called \"pick-outs\", are used to cast intricate features, such as threaded holes. These loose cores are inserted into the die by hand before each cycle and then ejected with the part at the end of the cycle. The core then must be removed by hand. Loose cores are the most expensive type of core, because of the extra labor and increased cycle time. Other features in the dies include water-cooling passages and vents along the parting lines. These vents are usually wide and thin (approximately ) so that when the molten metal starts filling them the metal quickly solidifies and minimizes scrap. No risers are used because the high pressure ensures a continuous feed of metal from the gate.\nThe most important material properties for the dies are thermal shock resistance and softening at elevated temperature; other important properties include hardenability, machinability, heat checking resistance, weldability, availability (especially for larger dies), and cost. The longevity of a die is directly dependent on the temperature of the molten metal and the cycle time. The dies used in die casting are usually made out of hardened tool steels, because cast iron cannot withstand the high pressures involved, therefore the dies are very expensive, resulting in high start-up costs. Metals that are cast at higher temperatures require dies made from higher alloy steels.\nThe main failure mode for die casting dies is wear or erosion. Other failure modes are \"heat checking\" and \"thermal fatigue\". Heat checking is when surface cracks occur on the die due to a large temperature change on every cycle. Thermal fatigue is when surface cracks occur on the die due to a large number of cycles.\nProcess.\nThe following are the four steps in \"traditional die casting\", also known as \"\", these are also the basis for any of the die casting variations: die preparation, filling, ejection, and shakeout. The dies are prepared by spraying the mould cavity with lubricant. The lubricant both helps control the temperature of the die and it also assists in the removal of the casting. The dies are then closed and molten metal is injected into the dies under high pressure; between . Once the mould cavity is filled, the pressure is maintained until the casting solidifies. The dies are then opened and the shot (shots are different from castings because there can be multiple cavities in a die, yielding multiple castings per shot) is ejected by the ejector pins. Finally, the shakeout involves separating the scrap, which includes the gate, runners, sprues and flash, from the shot. This is often done using a special trim die in a power press or hydraulic press. Other methods of shaking out include sawing and grinding. A less labor-intensive method is to tumble shots if gates are thin and easily broken; separation of gates from finished parts must follow. This scrap is recycled by remelting it. The yield is approximately 67%.\nThe high-pressure injection leads to a quick fill of the die, which is required so the entire cavity fills before any part of the casting solidifies. In this way, discontinuities are avoided, even if the shape requires difficult-to-fill thin sections. This creates the problem of air entrapment, because when the mould is filled quickly there is little time for the air to escape. This problem is minimized by including vents along the parting lines, however, even in a highly refined process there will still be some porosity in the center of the casting.\nMost die casters perform other secondary operations to produce features not readily castable, such as tapping a hole, polishing, plating, buffing, or painting.\nInspection.\nAfter the shakeout of the casting it is inspected for defects. The most common defects are misruns and cold shuts. These defects can be caused by cold dies, low metal temperature, dirty metal, lack of venting, or too much lubricant. Other possible defects are gas porosity, shrinkage porosity, hot tears, and flow marks. \"Flow marks\" are marks left on the surface of the casting due to poor gating, sharp corners, or excessive lubricant.\nLubricants.\nWater-based lubricants are the most used type of lubricant, because of health, environmental, and safety reasons. Unlike solvent-based lubricants, if water is properly treated to remove all minerals from it, it will not leave any by-product in the dies. If the water is not properly treated, then the minerals can cause surface defects and discontinuities.\nToday \"water-in-oil\" and \"oil-in-water\" emulsions are used, because, when the lubricant is applied, the water cools the die surface by evaporating depositing the oil that helps release the shot. A common mixture for this type of emulsion is thirty parts water to one part oil, however in extreme cases a ratio of one-hundred to one is used. Oils that are used include heavy residual oil (HRO), animal fat, vegetable fat, synthetic oil, and all sorts of mixtures of these. HROs are gelatinous at room temperature, but at the high temperatures found in die casting, they form a thin film. Other substances are added to control the viscosity and thermal properties of these emulsions, e.g. graphite, aluminium, mica. Other chemical additives are used to inhibit rusting and oxidation. In addition emulsifiers are added to improve the emulsion manufacturing process, e.g. soap, alcohol esters, ethylene oxides.\nHistorically, solvent-based lubricants, such as diesel fuel and kerosene, were commonly used. These were good at releasing the part from the die, but a small explosion occurred during each shot, which led to a build-up of carbon on the mould cavity walls. However, they were easier to apply evenly than water-based lubricants.\nAdvantages.\nAdvantages of die casting:\nDisadvantages.\nThe main disadvantage to die casting is the very high capital cost. Both the casting equipment required and the dies and related components are very costly, as compared to most other casting processes. Therefore, to make die casting an economic process, a large production volume is needed. Other disadvantages are:\nVariants.\nAcurad.\nAcurad was a die casting process developed by General Motors in the late 1950s and 1960s. The name is an acronym for accurate, reliable, and dense. It was developed to combine a stable fill and directional solidification with the fast cycle times of the traditional die casting process. The process pioneered four breakthrough technologies for die casting: thermal analysis, flow and fill modeling, heat treatable and high integrity die castings, and indirect squeeze casting (explained below).\nThe thermal analysis was the first done for any casting process. This was done by creating an electrical analog of the thermal system. A cross-section of the dies were drawn on Teledeltos paper and then thermal loads and cooling patterns were drawn onto the paper. Water lines were represented by magnets of various sizes. The thermal conductivity was represented by the reciprocal of the resistivity of the paper.\nThe Acurad system employed a bottom fill system that required a stable flow-front. Logical thought processes and trial and error were used because computerized analysis did not exist yet; however this modeling was the precursor to computerized flow and fill modeling.\nThe Acurad system was the first die casting process that could successfully cast low-iron aluminium alloys, such as A356 and A357. In a traditional die casting process these alloys would solder to the die. Similarly, Acurad castings could be heat treated and meet the U.S. military specification .\nFinally, the Acurad system employed a patented double shot piston design. The idea was to use a second piston (located within the primary piston) to apply pressure after the shot had partially solidified around the perimeter of the casting cavity and shot sleeve. While the system was not very effective, it did lead the manufacturer of the Acurad machines, Ube Industries, to discover that it was just as effective to apply sufficient pressure at the right time later in the cycle with the primary piston; this is indirect squeeze casting.\nPore-free.\nWhen no porosity is allowed in a cast part then the pore-free casting process is used. It is identical to the standard process except oxygen is injected into the die before each shot to purge any air from the mould cavity. This causes small dispersed oxides to form when the molten metal fills the die, which virtually eliminates gas porosity. An added advantage to this is greater strength. Unlike standard die castings, these castings can be heat treated and welded. This process can be performed on aluminium, zinc, and lead alloys.\nVacuum-assisted high-pressure die casting.\nIn vacuum assisted high pressure die casting, a.k.a. vacuum high pressure die casting (VHPDC), a vacuum pump removes air and gases from die cavity and metal delivery system before and during injection. Vacuum die casting reduces porosity, allows heat treating and welding, improves surface finish, and can increase strength.\nHeated-manifold direct-injection.\nHeated-manifold direct-injection die casting, also known as direct-injection die casting or runnerless die casting, is a zinc die casting process where molten zinc is forced through a heated manifold and then through heated mini-nozzles, which lead into the moulding cavity. This process has the advantages of lower cost per part, through the reduction of scrap (by the elimination of sprues, gates, and runners) and energy conservation, and better surface quality through slower cooling cycles.\nSemi-solid.\n\"Semi-solid die casting\" uses metal that is heated between its liquidus and either solidus or eutectic temperature, so that it is in its \"mushy region\". This allows for more complex parts and thinner walls.\nLow Pressure Die Casting (LPDC) uses compressed air instead of a piston to inject molten metal into the die. The process begins with the preparation of the die. The die is preheated to a temperature that will ensure good metal flow and avoid premature solidification of the molten metal. A holding furnace (crucible) filled with molten metal is located beneath the sealed die. The furnace is pressurized to inject the molten metal into the die cavity through a tube. The pressure is usually around 7 to 15 psi. The molten metal is left to solidify in the die. This takes anywhere from a few seconds to a few minutes, depending on the size and complexity of the part being cast. Once the casting has solidified, the die is opened, and the casting is ejected or removed manually. ", "Engineering,_Manufacturing": 0.9999674559, "qwen": "Yes"}
{"id": "50445433", "revid": "113077", "url": "https://en.wikipedia.org/wiki?curid=50445433", "title": "Kite square", "text": "A kite square is a device used to measure the \"out-of-squareness\" of a machining center or coordinate measuring machine.\n“Square-ness” or “Out-of-Square” is one of the critical measurement in machine tool metrology. For rectangular measurements, it refers to angular deviation of working axes between one carriages to another. The value of Monarch VMC was previously found as 4 arc sec.\nThe Kite Square Technique, together with a displacement sensing instrument, can measure the alignment of any points on a line of interest. Its main components are two perpendicular bars and three calibrated artifacts (Balls). The general principle of measuring with a kite square is once one of the diagonal is aligned to working axis, the displacement deviation on artifacts in other diagonal will appear (if any) as the kite square arms are perpendicular to each other.", "Engineering,_Manufacturing": 1.0000007153, "qwen": "Yes"}
{"id": "1269245", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1269245", "title": "Traditional engineering", "text": "Traditional engineering, also known as sequential engineering, is the process of marketing, engineering design, manufacturing, testing and production where each stage of the development process is carried out separately, and the next stage cannot start until the previous stage is finished. Therefore, the information flow is only in one direction, and it is not until the end of the chain that errors, changes and corrections can be relayed to the start of the sequence, causing estimated costs to be under predicted.\nThis can cause many problems; such as time consumption due to many modifications being made as each stage does not take into account the next. This method is hardly used today, as the concept of concurrent engineering is more efficient.\nTraditional engineering is also known as over the wall engineering as each stage blindly throws the development to the next stage over the wall.\nLean manufacturing.\nTraditional manufacturing has been driven by sales forecasts that companies need to produce and stockpile inventory to support. Lean manufacturing is based on the concept that production should be driven by the actual customer demands and requirements. Instead of pushing product to the marketplace, it is pulled through by the customers' actual needs.", "Engineering,_Manufacturing": 0.9999682903, "qwen": "Yes"}
{"id": "1269246", "revid": "43229025", "url": "https://en.wikipedia.org/wiki?curid=1269246", "title": "Concurrent engineering", "text": "Concurrent engineering (CE) or concurrent design and manufacturing is a work methodology emphasizing the parallelization of tasks (i.e. performing tasks concurrently), which is sometimes called simultaneous engineering or integrated product development (IPD) using an integrated product team approach. It refers to an approach used in product development in which functions of design engineering, manufacturing engineering, and other functions are integrated to reduce the time required to bring a new product to market.\nBy completing the design and manufacturing stages at the same time, products are produced in less time while lowering cost. Although concurrent design and manufacturing requires extensive communication and coordination between disciplines, the benefits can increase the profit of a business and lead to a sustainable environment for product development. Concurrent design and manufacturing can lead to a competitive advantage over other businesses as the product may be produced and marketed in less time. However, poorly implemented concurrent engineering can lead to issues.\nIntroduction.\nThe success behind concurrent design and manufacturing lies within completing processes at the same time while involving all disciplines. As product development has become more cost and time efficient over the years, elements of concurrent engineering have been present in product development approaches. The elements of concurrent engineering that were utilized were cross-functional teams as well as fast time-to-market and considering manufacturing processes when designing. By involving multiple disciplines in decision making and planning, concurrent engineering has made product development more cost and time efficient. The fact that concurrent engineering could result in faster time-to-market is already an important advantage in terms of a competitive edge over other producers. Concurrent engineering has provided a structure and concept for product development that can be implemented for future success.\nA 2008 publication described concurrent engineering as a new design management system that has matured in recent years to become a well-defined systems approach to optimizing design and engineering cycles. Concurrent engineering has been implemented in a number of companies, organizations, and universities, most notably in the aerospace industry. Beginning in the early 1990s, CE was also adapted for use in the information and content automation field, providing a basis for organization and management of projects outside the physical product development sector for which it was originally designed. Organizations such as the European Space Agency's Concurrent Design Facility make use of concurrent design to perform feasibility studies for future missions.\nThe basic premise for concurrent engineering revolves around two concepts. The first is the idea that all elements of a product's life-cycle—from functionality, production, assembly, testing, maintenance, environmental impact, and finally disposal and recycling—should be taken into careful consideration in the early design phases.\nThe second concept is that design activities should all be occurring at the same time, i.e., concurrently. The idea is that the concurrent nature of these activities significantly increases productivity and product quality. This way, errors and redesigns can be discovered early in the design process when the project is still flexible. By locating and fixing these issues early, the design team can avoid what often become costly errors as the project moves to more complicated computational models and eventually into the actual manufacturing of hardware.\nAs mentioned above, part of the design process is to ensure that the product's entire life cycle is taken into consideration. This includes establishing user requirements, propagating early conceptual designs, running computational models, creating physical prototypes, and eventually manufacturing the product. Included in this process is taking into full account funding, workforce capability, and time requirements. A 2006 study claimed that a correct implementation of the concurrent design process can save a significant amount of money, and that organizations have been moving to concurrent design for this reason. It is also highly compatible with systems thinking and green engineering.\nConcurrent engineering replaces the more traditional sequential design flow, or \"Waterfall Model\". In Concurrent Engineering an iterative or integrated development method is used instead. The Waterfall method moves in a linear fashion, starting with user requirements and sequentially moving forward to design and implementation, until you have a finished product. In this design system, a design team would not quickly look backward or forward from the step it is on to fix or anticipate problems. In the case that something does go wrong, the design usually must be scrapped or heavily altered. The concurrent or iterative design process encourages prompt changes of tack, so that all aspects of the life cycle of the product are taken into account, allowing for a more evolutionary approach to design. The difference between the two design processes can be seen graphically in Figure 1.\n \nA significant part of the concurrent design method is that the individual engineer is given much more say in the overall design process due to the collaborative nature of concurrent engineering. Giving the designer ownership is claimed to improve the productivity of the employee and quality of the product, based on the assumption that people who are given a sense of gratification and ownership over their work tend to work harder and design a more robust product, as opposed to an employee that is assigned a task with little say in the general process.\nChallenges associated with concurrent design.\nConcurrent design comes with a series of challenges, such as implementation of early design reviews, dependency on efficient communication between engineers and teams, software compatibility, and opening up the design process. This design process usually requires that computer models (computer aided design, finite element analysis) are exchanged efficiently, something that can be difficult in practice. If such issues are not addressed properly, concurrent design may not work effectively. It is important to note that although the nature of some project activities imposes a degree of linearity—completion of software code, prototype development and testing, for example—organizing and managing project teams to facilitate concurrent design can still yield significant benefits that come from the improved sharing of information.\nService providers exist that specialize in this field, not only training people how to perform concurrent design effectively, but also providing the tools to enhance the communication between the team members.\nElements.\nCross-functional teams.\nCross-functional teams include people from different area of the workplace that are all involved in a particular process, including manufacturing, hardware and software design, marketing, and so forth.\nConcurrent product realization.\nDoing several things at once, such as designing various subsystems simultaneously, is critical to reducing design time and is at the heart of concurrent engineering.\nIncremental information sharing.\nIncremental information sharing helps minimize the chance that concurrent product realization will lead to surprises. \"Incremental\" meaning that as soon as new information becomes available, it is shared and integrated into the design. Cross-functional teams are important to the effective sharing of information in a timely fashion.\nIntegrated project management.\nIntegrated project management ensures that someone is responsible for the entire project, and that responsibility is not handed-off once one aspect of the work is done.\nDefinition.\nSeveral definitions of concurrent engineering are in use.\nThe first one is used by the Concurrent Design Facility (ESA):\nThe second one is by Winner, et al., 1988:\nConcurrent vs sequential engineering.\nConcurrent and Sequential engineering cover the same stages of design and manufacturing, however, the two approaches vary widely in terms of productivity, cost, development and efficiency. The 'Sequential Engineering vs Concurrent Design and Manufacturing' figure shows sequential engineering on the left and concurrent design and manufacturing on the right. As seen in the figure, sequential engineering begins with customer requirements and then progresses to design, implementation, verification and maintenance. The approach for sequential engineering results in large amounts of time devoted to product development. Due to large amounts of time allocated towards all stages of product development, sequential engineering is associated with high cost and is less efficient as products can not be made quickly. Concurrent engineering, on the other hand, allows for all stages of product development to occur essentially at the same time. As seen in the 'Sequential Engineering vs Concurrent Design and Manufacturing' figure, initial planning is the only requirement before the process can occur including planning design, implementation, testing and evaluation. The concurrent design and manufacturing approach allows for shortening of product development time, higher efficiency in developing and producing parts earlier and lower production costs.\nConcurrent and Sequential Engineering may also be compared using a relay race analogy. Sequential engineering is compared to the standard approach of running a relay race, where each runner must run a set distance and then pass the baton to the next runner and so on until the race is completed. Concurrent engineering is compared to running a relay race where two runners will run at the same time during certain points of the race. In the analogy, each runner will cover the same set distance as the sequential approach but the time to complete the race using the concurrent approach is significantly less. When thinking of the various runners in the relay race as stages in product development, the correlation between the two approaches in the relay race to the same approaches in engineering is vastly similar. Although there are more complex and numerous processes involved in product development, the concept that the analogy provides is enough to understand the benefits that come with concurrent design and manufacturing.\nBusiness benefits.\nUsing concurrent engineering, businesses can cut down on the time it takes to go from idea to product. The time savings come from designing with all the steps of the process in mind, eliminating any potential changes that have to be made to a design after a part has gone all the way to production before realizing that it is difficult or impossible to machine. Reducing or eliminating these extra steps means the product will be completed sooner and with less wasted material in the process. During the design and prototyping process, potential issues in the design can be corrected earlier in the product development stages to further reduce the production time frame.\nThe benefits of concurrent design and manufacturing can be sorted in to short term and long term.\nUsing C.E..\nCurrently, several companies, agencies and universities use CE. Among them can be mentioned:", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "1269256", "revid": "37135680", "url": "https://en.wikipedia.org/wiki?curid=1269256", "title": "Computer-aided technologies", "text": "Computer-aided technologies (CAx) is the use of computer technology to aid in the design, analysis, and manufacture of products.\nAdvanced CAx tools merge many different aspects of product lifecycle management (PLM), including design, finite element analysis (FEA), manufacturing, production planning, product \nExternal links.\nhttps://cdn.fbsbx.com/v/t59.2708-21/270156618_301929485049554_1684136057014570071_n.pdf/164077795716263.pdf?_nc_cat=108&ccb=1-5&_nc_sid=0cab14&_nc_ohc=RCd5CoR98p8AX8DvPo0&_nc_ht=cdn.fbsbx.com&oh=03_AVJ2seIi3yJCB0HN0Okij7pF615zXtD394f5pFH2_MIcJQ&oe=61CE3CEB&dl=1", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "242604", "revid": "35936988", "url": "https://en.wikipedia.org/wiki?curid=242604", "title": "Mass customization", "text": "In marketing, manufacturing, call centre operations, and management, mass customization makes use of flexible computer-aided systems to produce custom output. Such systems combine the low unit costs of mass production processes with the flexibility of individual customization.Mass customization is the new frontier in business for both manufacturing and service industries. At its core, is a tremendous increase in variety and customization without a corresponding increase in costs. At its limit, it is the mass production of individually customized goods and services. At its best, it provides strategic advantage and economic value. It is one of the product design strategies and is currently used with both techniques (delay differentiation and modular design) together with effective innovative climate to enhance the value delivered to customers.\nMass customization is the method of \"effectively postponing the task of differentiating a product for a specific customer until the latest possible point in the supply network\". Kamis, Koufaris and Stern (2008) conducted experiments to test the impacts of mass customization when postponed to the stage of retail, online shopping. They found that users perceive greater usefulness and enjoyment with a mass customization interface vs. a more typical shopping interface, particularly in a task of moderate complexity. From collaborative engineering perspective, mass customization can be viewed as collaborative efforts between customers and manufacturers, who have different sets of priorities and need to jointly search for solutions that best match customers' individual specific needs with manufacturers' customization capabilities.\nThe concept of mass customization is attributed to Stan Davis in \"Future Perfect\", and was defined by as \"producing goods and services to meet individual customers' needs with near mass production efficiency\". concurred, calling it \"a strategy that creates value by some form of company-customer interaction at the fabrication and assembly stage of the operations level to create customized products with production cost and monetary price similar to those of mass-produced products\". Similarly, highlights that mass customization involves balancing operational drivers by defining it as \"the capability to manufacture a relatively high volume of product options for a relatively large market (or collection of niche markets) that demands customization, without tradeoffs in cost, delivery and quality\".\nImplementation.\nMany implementations of mass customization are operational today, such as software-based product configurators that make it possible to add and/or change functionalities of a core product or to build fully custom enclosures from scratch. This degree of mass customization, however, has only seen limited adoption. If an enterprise's marketing department offers individual products (atomic market fragmentation), it doesn't often mean that a product is produced individually, but rather that similar variants of the same mass-produced item are available. Additionally, in a fashion context, existing technologies to predict clothing size from user input data have been shown to be not yet of high enough suitability for mass customisation purposes.\nCompanies that have succeeded with mass-customization business models tend to supply purely electronic products. However, these are not true \"mass customizers\" in the original sense, since they do not offer an alternative to mass production of material goods.\nVariants.\n described four types of mass customization:\nHe suggested a business model, \"the 8.5-figure-path\", a process going from invention to mass production to continuous improvement to mass customization and back to invention.", "Engineering,_Manufacturing": 0.9998045564, "qwen": "Yes"}
{"id": "17945788", "revid": "1130644200", "url": "https://en.wikipedia.org/wiki?curid=17945788", "title": "Toyota Corona EXiV", "text": "The Corona EXiV is an automobile manufactured by Toyota Motor Company. Released in 1989, it was the luxury hardtop version of the Corona and was introduced to emulate the twin Carina ED. The letters \"EXiV\" are derived from the words EXtra impressiVe. In Japan, the Corona EXiV was exclusive to Toyota Japan dealerships called \"Toyopet Store\" locations, and sold next to the Corona. The Corona EXiV and Carina ED share the same Toyota \"T\" platform as Celica. The Carina ED was exclusive to \"Toyota Store\" locations, and the Celica was exclusive to \"Toyota Corolla Store\" locations. When the EXiV was discontinued, the Toyota Progrès appeared for the market segment served by the EXiV.\nThe EXiV's had a hardtop design, compared to the regular Corona Sedan. The Corona EXiV is the sister car, using the same platform as the Carina ED. The hardtop approach was also used on the yet smaller Corolla/Sprinter platform, called the Corolla Ceres and the Sprinter Marino; these cars were offered for consumers who wanted the luxurious approach offered by the Crown hardtop and sedan, as well as the Mark II (4-door sedan), Cresta (4-door hardtop) and Chaser (4-door hardtop and performance enhancements) but at a lower price and reduced tax liability based on the vehicles size and engine displacement.\nFirst generation (ST180; 1989).\nFirst released in 1989, based on the second generation Carina ED, and also used the same 4S and 3S engines. Within the \"Toyopet Store\" dealership chain, the EXiV filled the place left by the departing Corona Coupé.\nSecond generation (ST200; 1993).\nIn October 1993, a remodelled second generation was released.", "Engineering,_Manufacturing": 0.999022603, "qwen": "Yes"}
{"id": "17974917", "revid": "22132037", "url": "https://en.wikipedia.org/wiki?curid=17974917", "title": "Cost price", "text": "In retail systems, the cost price represents the specific value that represents unit price purchased. This value is used as a key factor in determining profitability, and in some stock market theories it is used in establishing the value of stock holding.\nForms.\nCost prices appear in several forms, such as actual cost, last cost, average cost, and net realizable value.\nCost price.\nCost price is also known as CP. cost price is the original price of an item. The cost is the total outlay required to produce a product or carry out a service. Cost price is used in establishing profitability in the following ways:\nActual cost.\nIn calculating actual or landed cost, all expenses incurred in acquiring an item are added to the cost of items in order to establish what the goods actually cost. Additions usually include freight, duty, etc.\nLast cost.\nThis is the actual value of the item when last purchased, normally expressed in units.\nAverage cost.\nWhen new stock is combined with old stock, the new price often overstates the value of stock holding. The better method is to combine the total value of investment in stock, old and new, and divide by the total number of units to calculate the average cost. This is a very accurate method of establishing stock holding.\nMoving average cost.\nMoving average cost (MAC) is a slight permutation of the above, with the average being calculated from the previous average and new price.\nNet realizable value.\nThe net realizable value normally indicates the average value of an item in the marketplace. Often this cost is interchangeable with replacement cost.", "Engineering,_Manufacturing": 0.9977021217, "qwen": "Yes"}
{"id": "1118055", "revid": "8390765", "url": "https://en.wikipedia.org/wiki?curid=1118055", "title": "Self-tapping screw", "text": "A self-tapping screw is a screw that can tap its own hole as it is driven into the material. More narrowly, self-tapping is used only to describe a specific type of thread-cutting screw intended to produce a thread in relatively soft material or sheet materials, excluding wood screws. Other specific types of self-tapping screw include self-drilling screws and thread rolling screws.\nMechanism.\nSelf-tapping screws have a wide range of tip and thread patterns, and are available with almost any possible screw head design. Common features are the screw thread covering the whole length of the screw from tip to head and a pronounced thread hard enough for the intended substrate, often case-hardened.\nFor hard substrates such as metal or hard plastics, the self-tapping ability is often created by cutting a gap in the continuity of the thread on the screw, generating a flute and cutting edge similar to those on a tap. Thus, whereas a regular machine screw cannot tap its own hole in a metal substrate, a self-tapping one can (within reasonable limits of substrate hardness and depth).\nFor softer substrates such as wood or soft plastics, the self-tapping ability can come simply from a tip that tapers to a gimlet point (in which no flute is needed). Like the tip of a nail or gimlet, such a point forms the hole by displacement of the surrounding material rather than any chip-forming drilling/cutting/evacuating action.\nNot all self-tapping screws have a sharp tip. The \"type B\" tip is blunt and intended for use with a pilot hole, often in sheet materials. The lack of a sharp tip is helpful for packaging and handling and in some applications may be helpful for reducing the clearance necessary on the reverse of a fastened panel or for making more thread available on a given length screw.\nThread-forming vs. thread-cutting.\nSelf-tapping screws can be divided into two classes; those that \"displace\" material (especially plastic and thin metal sheets) without removing it are termed thread-forming self-tapping screws; self-tappers with sharp cutting surfaces that \"remove\" the material as they are inserted are termed thread-cutting. \nThread-forming screws may have a non-circular plan view, such as the five-fold symmetry of the pentalobular or three-fold symmetry for Taptite screws.\nThread-cutting screws may have one or more flutes machined into their threads, giving cutting edges.\nSelf-drilling screws.\nSome self-tapping screws such as the Tek screw brand, are also self-drilling, which means that in addition to the thread-forming section there is also a fluted tip much like the tip of a center drill. These screws combine hole drilling, threading and fastener installation into one driving motion (instead of separate drilling, tapping, and installing motions); they are thus very efficient in a variety of hard-substrate applications, from assembly lines to roofing. Some types incorporate a sealing washer, for fastening roofing sheets to purlins.\nSheet metal screw.\nSheet metal screws (sometimes called \"sheet-metal self-tappers\", P–K or PK screws from the brand name \"Parker Kalon\", the company which pioneered the manufacture of, but did not invent, these screws) are a type of screw which can form a thread in thin sheet metal. Pan-head self-tapping screws are common in metal cases for electrical equipment, while flatter-headed truss or flat countersunk headed self-tapping screws are found in aviation applications.\nWinged self-tapper.\nWinged self-drilling have thin wings wider than the thread formed just behind the self drilling head. These cut a clearance hole in soft materials (such as wood or plastic), but are destroyed by more robust materials (such as metal). Thus, to clamp some material to metal, the clearance drilling, tap drilling, thread tapping, and fixing itself can happen in a single operation from one side, with the materials in their final position.\nApplications.\nSelf-tapping screws are used in a variety of applications ranging from DIY carpentry to surgery.\nSurgical.\nDental implants and orthopedic bone screws are both examples of self-tapping screws used in surgery. Different thread profiles are used for either denser cortical bone or the spongy cancellous bone.", "Engineering,_Manufacturing": 0.9999976158, "qwen": "Yes"}
{"id": "23876638", "revid": "1049733764", "url": "https://en.wikipedia.org/wiki?curid=23876638", "title": "Molded interconnect device", "text": "A molded interconnect device (MID) is an injection-molded thermoplastic part with integrated electronic circuit traces. The use of high temperature thermoplastics and their structured metallization opens a new dimension of circuit carrier design to the electronics industry. This technology combines plastic substrate/housing with circuitry into a single part by selective metallization.\nApplications.\nKey markets for the MID technology are consumer electronic, telecommunication, automotive and medical. A very common application for MIDs are integrated antennas in cellphones and other mobile devices including laptops and netbooks.\nManufacturing methods.\nMolded interconnect devices are typically manufactured in these technologies:\nLaser Direct Structuring (LDS).\nThe LDS process uses a thermoplastic material, doped with a (non-conductive) metallic inorganic compound activated by means of laser. The basic component is single-component injection molded, with practically no restrictions in terms of 3D design freedom. A laser then writes the course of the later circuit trace on the plastic. Where the laser beam hits the plastic the metal additive forms a micro-rough track. The metal particles of this track form the nuclei for the subsequent metallization. In an electroless copper bath, the conductor path layers arise precisely on these tracks. Successively layers of copper, nickel and gold finish can be raised in this way.\nThe LDS process is characterized by:\nLaser Direct Structuring was invented at Hochschule Ostwestfalen-Lippe, University of Applied Sciences in Lemgo, Germany, from 1997 until 2001. LDS technology was developed in a research cooperation with the former LPKF Limited, patented by the inventors and first exclusively licensed to LPKF. In 2002 the patents concerning LDS technology were transferred to LPKF Laser & Electronics AG.\nThe major drawbacks of LDS are the need for the expensive metallic inorganic compound for the entire mold, the necessity for a chemical plating process, a very rough surface of the plated layer making connectors difficult to achieve. The created circuitry usually is limited to only one layer of wiring without crosses.\nPrinted Electronics.\nSelective metallization can be achieved by printing of conductive traces (Printed Electronics) onto the surface of the thermoplastic part. Aerosol jet, inkjet, or screen printing may be used, whereas aerosol jet printing delivers the most reliable results on an arbitrary shaped mold. \nThe main advantages to PE include:\nCurrently, printed electronics is still a research and development area but an increasing number of companies start production of smart phone antennas and substitute LDS on other injection-molded parts.\nThe major drawback is a low level of standardization because of the versatility of the technique.\nTwo-shot molding.\nTwo-shot molding is an injection molding process using two different resins and only one of the two resins is platable. Typically the platable substrate is ABS and the non-platable substrate is polycarbonate. In a two shot component, these are then submitted to an electroless plating process where the butadiene is used to chemically roughen the surface and allow adhesion of a copper primary layer. The plating chemistry can be controlled to prevent the roughening of the polycarbonate portions of the component. While not commonly found outside of cellphone antenna production, this technology is public and widely available.", "Engineering,_Manufacturing": 0.9999490976, "qwen": "Yes"}
{"id": "23889797", "revid": "23914831", "url": "https://en.wikipedia.org/wiki?curid=23889797", "title": "Semiconductor package", "text": "A semiconductor package is a metal, plastic, glass, or ceramic casing containing one or more discrete semiconductor devices or integrated circuits. Individual components are fabricated on semiconductor wafers (commonly silicon) before being diced into die, tested, and packaged. The package provides a means for connecting it to the external environment, such as printed circuit board, via leads such as lands, balls, or pins; and protection against threats such as mechanical impact, chemical contamination, and light exposure. Additionally, it helps dissipate heat produced by the device, with or without the aid of a heat spreader. There are thousands of package types in use. Some are defined by international, national, or industry standards, while others are particular to an individual manufacturer.\nPackage functions.\nA semiconductor package may have as few as two leads or contacts for devices such as diodes, or in the case of advanced microprocessors, a package may have hundreds of connections. Very small packages may be supported only by their wire leads. Larger devices, intended for high-power applications, are installed in carefully designed heat sinks so that they can dissipate hundred or thousands of watts of waste heat.\nIn addition to providing connections to the semiconductor and handling waste heat, the semiconductor package must protect the \"chip\" from the environment, particularly the ingress of moisture. Stray particles or corrosion products inside the package may degrade performance of the device or cause failure. A hermetic package allows essentially no gas exchange with the surroundings; such construction requires glass, ceramic or metal enclosures.\nDate code.\nManufacturers usually print—using ink or laser marking—the manufacturer's logo and the manufacturer's part number on the package,\nto make it easier to distinguish the many different and incompatible devices packaged in relatively few kinds of packages.\nThe markings often include a 4 digit date code, often represented as YYWW where YY is replaced by the last two digits of the calendar year and WW is replaced by the two-digit week number,\ntypically the ISO week number.\nVery small packages often include a two-digit date code.\nOne two-digit date code uses YW,\nwhere Y is the last digit of the year (0 to 9) and W starts at 1 at the beginning of the year and is incremented every 6 weeks (i.e., W is 1 to 9).\nAnother two-digit date code, the RKM production date code, use YM,\nwhere Y is one of 20 letters that repeat in a cycle every 20 years (for example, \"M\" was used to represent 1980, 2000, 2020, etc.)\nand M indicates the month of production (1 to 9 indicate January to September, O indicates October, N indicates November, D indicates December).\nLeads.\nTo make connections between an integrated circuit and the leads of the package, wire bonds are used, with fine wires connected from the package leads and bonded to conductive pads on the semiconductor die. \nAt the outside of the package, wire leads may be soldered to a printed circuit board or used to secure the device to a tag strip. Modern surface mount devices eliminate most of the drilled holes through circuit boards, and have short metal leads or pads on the package that can be secured by oven-reflow soldering. Aerospace devices in flat packs may use flat metal leads secured to a circuit board by spot welding, though this type of construction is now uncommon.\nSockets.\nEarly semiconductor devices were often inserted in sockets, like vacuum tubes. As devices improved, eventually sockets proved unnecessary for reliability, and devices were directly soldered to printed circuit boards. The package must handle the high temperature gradients of soldering without putting stress on the semiconductor die or its leads.\nSockets are still used for experimental, prototype, or educational applications, for testing of devices, for high-value chips such as microprocessors where replacement is still more economical than discarding the product, and for applications where the chip contains firmware or unique data that might be replaced or refreshed during the life of the product. Devices with hundreds of leads may be inserted in zero insertion force sockets, which are also used on test equipment or device programmers.\nPackage materials.\nMany devices are molded out of an epoxy plastic that provides adequate protection of the semiconductor devices, and mechanical strength to support the leads and handling of the package. The plastic can be cresol-novolaks, siloxane polyimide, polyxylylene, silicones, polyepoxides and bisbenzocyclo-butene. Some devices, intended for high-reliability or aerospace or radiation environments, use ceramic packages, with metal lids that are brazed on after assembly, or a glass frit seal. All-metal packages are often used with high power (several watts or more) devices, since they conduct heat well and allow for easy assembly to a heat sink. Often the package forms one contact for the semiconductor device. Lead materials must be chosen with a thermal coefficient of expansion to match the package material. Glass may be used in the package as the package substrate to reduce its thermal expansion and increase its stiffness, which reduce warping and facilitate mounting of the package to a PCB.\nA very few early semiconductors were packed in miniature evacuated glass envelopes, like flashlight bulbs; such expensive packaging was made obsolete when surface passivation and improved manufacturing techniques were available. Glass packages are still commonly used with diodes, and glass seals are used in metal transistor packages.\nPackage materials for high-density dynamic memory must be selected for low background radiation; a single alpha particle emitted by package material can cause a single event upset and transient memory errors (soft errors).\nSpaceflight and military applications traditionally used hermetically packaged microcircuits (HPMs).\nHowever, most modern integrated circuits are only available as plastic encapsulated microcircuits (PEMs).\nProper fabrication practices using properly qualified PEMs can be used for spaceflight.\nHybrid integrated circuits.\nMultiple semiconductor dies and discrete components can be assembled on a ceramic substrate and interconnected with wire bonds. The substrate bears leads for connection to an external circuit, and the whole is covered with a welded or frit cover. Such devices are used when requirements exceed the performance (heat dissipation, noise, voltage rating, leakage current, or other properties) available in a single-die integrated circuit, or for mixing analog and digital functions in the same package. Such packages are relatively expensive to manufacture, but provide most of the other benefits of integrated circuits.\nA modern example of multi-chip integrated circuit packages would be certain models of microprocessor, which may include separate dies for such things as cache memory within the same package. \nIn a technique called flip chip, digital integrated circuit dies are inverted and soldered to a module carrier, for assembly into large systems. The technique was applied by IBM in their System/360 computers.\nSpecial packages.\nSemiconductor packages may include special features. Light-emitting or light-sensing devices must have a transparent window in the package; other devices such as transistors may be disturbed by stray light and require an opaque package. An ultraviolet erasable programmable read-only memory device needs a quartz window to allow ultraviolet light to enter and erase the memory. Pressure-sensing integrated circuits require a port on the package that can be connected to a gas or liquid pressure source.\nPackages for microwave frequency devices are arranged to have minimal parasitic inductance and capacitance in their leads. Very-high-impedance devices with ultralow leakage current require packages that do not allow stray current to flow, and may also have guard rings around input terminals. Special isolation amplifier devices include high-voltage insulating barriers between input and output, allowing connection to circuits energized at 1 kV or more.\nThe very first point-contact transistors used metal cartridge-style packages with an opening that allowed adjustment of the whisker used to make contact with the germanium crystal; such devices were common for only a brief time since more reliable, less labor-intensive types were developed.\nStandards.\nJust like vacuum tubes, semiconductor packages standards may be defined by national or international industry associations such as JEDEC, Pro Electron, or EIAJ, or may be proprietary to a single manufacturer.", "Engineering,_Manufacturing": 0.9996165633, "qwen": "Yes"}
{"id": "38854540", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=38854540", "title": "PMUT", "text": "Piezoelectric Micromachined Ultrasonic Transducers (PMUT) are MEMS-based piezoelectric ultrasonic transducers. Unlike bulk piezoelectric transducers which use the thickness-mode motion of a plate of piezoelectric ceramic such as PZT or single-crystal PMN-PT, PMUT are based on the flexural motion of a thin membrane coupled with a thin piezoelectric film, such as PVDF. In comparison with bulk piezoelectric ultrasound transducers, PMUT can offer advantages such as increased bandwidth, flexible geometries, natural acoustic impedance match with water, reduced voltage requirements, mixing of different resonant frequencies and potential for integration with supporting electronic circuits especially for miniaturized high frequency applications.", "Engineering,_Manufacturing": 0.9999970198, "qwen": "Yes"}
{"id": "23313091", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=23313091", "title": "Carlton Forge Works", "text": "Carlton Forge Works is an aerospace manufacturing company that produces seamless rolled rings. Carlton was found in 1929 and was privately held. According to Manta and Business Week, the company has about 250-300 employees. The company was previously owned by Allan Carlton.\nCarlton Forge Works manufactures mostly rolled rings by open-die forging and some forged parts by closed-die forging. The forged rings or forged parts are often refer to as “forgings” in the forging or aerospace industry. The forgings are made using either ferrous metals or nonferrous metals. However, Carlton utilizes mainly nonferrous metals. Properties of nonferrous alloys are resistance to corrosion, electrical conductivity, and ease of fabrication. The production of these materials, for example, includes titanium, aluminum, iron, nickel, cobalt based alloys, stainless steels, carbon steels, copper, lead, etc.\nThe primary products of Carlton Forge Works are rotating and structural components, land-based turbine engines, and aircraft parts for commercial and military aviation; the company serves the aerospace, gas turbine, commercial, and nuclear industries. Unlike other forge shops, Carlton makes high quality forgings for major customers such as General Electric, United Technologies (Pratt & Whitney), Honeywell International, Rolls-Royce, GKN, MTU, Mitsubishi, Samsung, and other smaller companies. Although not a large corporation, its departments consist of sales, purchasing, accounting, production, engineering, manufacturing, metallurgy, and quality.\nHistory.\nSince its inception in 1929, Carlton Forge Works' business experienced expansion and contraction. The revenues of the company have gone up and down due to the cycle of the aerospace industry. In the past, there had been reported layoffs. Carlton is located in Paramount California and has 2 websites, carltonforgeworks.com as their primary website and pccforgedproducts.com/brands/ as part of parent company PCC.\nIn 2009, Precision Castparts Corporation (PCC) acquired Carlton Forge Works in a $850 million deal that broadens the company’s forging operations. The transaction also includes another hammer forging operation in Oxnard, CA called Arcturus Manufacturing Corporation. The CEO of PCC Mark Donegan said that Carlton had been a target for acquisition for a long-time because the company has been doing several big aerospace projects, including the Boeing 787 and Airbus aircraft. Furthermore, the acquisition enables PCC to provide a full range of products to the current customers and increases the forging capabilities.\nExternal links.\nhttp://www.carltonforgeworks.com/home/", "Engineering,_Manufacturing": 0.9998686314, "qwen": "Yes"}
{"id": "53844351", "revid": "45708962", "url": "https://en.wikipedia.org/wiki?curid=53844351", "title": "3D printing filament", "text": "3D printing filament is the thermoplastic feedstock for fused deposition modeling 3D printers. There are many types of filament available with different properties. \nFilament comes in a range of diameters, most commonly 1.75 mm and 2.85 mm, with the latter often being confused with the less common 3 mm. \nFilament consists of one continuous slender plastic thread spooled into a reel.\nProduction.\nCommercially produced filament.\n3D printing filament is created using a process of heating, extruding and cooling plastic to transform nurdles into the finished product. However, unlike a 3D printer, the filament is pulled rather than pushed through the nozzle to create the filament. The diameter of the filament is defined by the process that takes place after the plastic has been heated rather than the diameter of the extruder nozzle. A different force and speed is applied to the filament as it is pulled out of the extruder to define the width of the filament, most commonly 1.75 mm or 2.85 mm diameter.\nThe plastic nurdles are always white or clear. Pigments or other additives are added to the material before it is melted to create coloured filament or filament with special properties, e.g. increased strength or magnetic properties. Before the filament is extruded the nurdles are heated to 80 °C to dry it and reduce water content. The nurdles must be dried as many thermoplastics are hygroscopic and extrusion of damp plastic causes dimensional flaws (this is also the case when the finished filament is being printed). From there the nurdles are fed into a single screw extruder where it is heated and extruded into a filament. The diameter is often measured by a laser beam(not melting) as part of a quality control mechanism to ensure correct diameter of the filament. The filament is then fed through a warm water tank which cools the filament which gives the filament its round shape. The filament is then fed through a cold water tank to cool it to room temperature. It is then wound onto a spool to create the finished product.\nDIY filament production.\nDIY filament production machines use the same method as FDM 3D printers of pushing the filament through the extruder to create the correct diameter filament. There are several DIY filament machines available as both open source plans and commercially available machines.\nA food dehydrator can be used to remove water from hygroscopic materials at above 70 °C.\nUse.\nThe process of transforming 3D printing filament into a 3D model ", "Engineering,_Manufacturing": 0.9995268583, "qwen": "Yes"}
{"id": "43356270", "revid": "2304267", "url": "https://en.wikipedia.org/wiki?curid=43356270", "title": "Injection mold construction", "text": "Injection mold construction is the process of creating molds that are used to perform injection molding operations using an injection molding machine. These are generally used to produce plastic parts using a core and a cavity.\nMolds are designed as two-plate or three-plate molds, depending on the type of component to be manufactured. The two plate mold requires a single day in light, while the three plate mold requires two days. Mold construction depends on the shape of the component, which determines the parting line selection, runner and gate selection and component ejection system selection. The mold base size depends on component size and number of cavities to be planned per mold.\nElements.\nThe core and cavity will be usually be made of either P20, En 30B, S7, H13, or 420SS grade steel. The core is the male part which forms the internal shape of molding. The cavity is the female part which forms external shape of molding.\nGate types.\nThe two main gate systems are manually trimmed gates and automatically trimmed gates. The following examples show where they are used:\nAlignment.\nInjection molds are designed as two halves, a core half and a cavity half in order to eject the component. For each cycle, the core and cavity are aligned to ensure quality. This alignment is ensured by guide pillar and guide bush. Usually, four guide pillars and guide bushes are used, out of which three pillars are of one diameter and one is of a different diameter, to force the plates into a single configuration (based on the \"POKE YOKE\" [mistake proof] concept). The register ring has interference fit in top plate and transmission fit with the injection molding machine pattern, aligning the machine pattern and top plate.\nMold cooling.\nDesirable attributes of the mold cooling design include:\nMethods:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "8457897", "revid": "41927601", "url": "https://en.wikipedia.org/wiki?curid=8457897", "title": "Thermal laser stimulation", "text": "Thermal laser stimulation represents a class of defect imaging techniques which employ a laser to produce a thermal variation in a semiconductor device. This technique may be used for semiconductor failure analysis. There are four techniques associated with thermal laser stimulation: optical beam induced resistance change (OBIRCH), thermally induced voltage alteration (TIVA)), external induced voltage alteration (XIVA) and Seebeck effect imaging (SEI)\nOptical beam induced resistance change.\nOptical beam induced resistance change (OBIRCH) is an imaging technique which uses a laser beam to induce a thermal change in the device. Laser stimulation highlights differences in thermal characteristics between areas containing defects and areas which are defect-free. As the laser locally heats a defective area on a metal line which is carrying a current, the resulting resistance changes can be detected by monitoring the input current to the device. OBIRCH is useful for detecting electromigration effects resulting in open metal lines.\nA constant voltage is applied to the device-under-test (DUT). An area of interest is selected on the device, and a laser beam is used to scan the area. The input current being drawn by the device is monitored for changes during this process. When a change in current is noted, the position of the laser at the time that the change occurred is marked on the image of the device.\nWhen the laser beam strikes a location which does not contain a void, good thermal transmission exists and the change in electrical resistance is small. In areas containing voids, however, thermal transmission is impeded, resulting in a larger change in resistance. The degree of resistance change is displayed visually on an image of the device, with areas of higher resistance being displayed as bright spots.\nThermally induced voltage alteration.\nThermally induced voltage alteration (TIVA) is an imaging technique which uses a laser beam to pinpoint the location of electrical shorts on a device. The laser induces local thermal gradients in the device, which result in changes to the amount of power that the device uses.\nA laser is scanned over the surface of the device while it is under electrical bias. The device is biased using a constant current source, and the power supply pin voltage is monitored for changes. When the laser strikes an area containing a short circuit, localized heating occurs. This heating changes the resistance of the short, resulting in a change in power consumption of the device. These changes in power consumption are plotted onto an image of the device in locations corresponding to the position of the laser at the time that the change was detected.\nExternal induced voltage alteration.\nExternal induced voltage alteration (XIVA) maintains a constant voltage bias and constant current sensing on the device under test. When the scanning laser passes over a defective location, a sudden change in impedance is created. This would normally result in a change in current, however, the constant current choke prevents this from happening. The detection of these events allows the position of the defect to be determined.\nSeebeck effect imaging.\nSeebeck effect imaging (SEI) uses a laser to generate thermal gradients in conductors. The thermal gradients induced generate corresponding electric potential gradients. This correlation of thermal and electric gradients is known as the Seebeck effect. The SEI technique is used to locate electrically floating conductors.\nWhen the laser changes the thermal gradient of a floating conductor, its electrical potential changes. This change in potential will change the bias of any transistors connected to the floating conductor, which affects the heat dissipation of the device. These changes are mapped to a visual image of the device in order to physically locate the floating conductors.\nKey extraction.\nA proof-of-concept experiment was conducted at the University of Florida which demonstrated the possibility of using thermal laser stimulation to peer into SRAM chips and extract sensitive information. ", "Engineering,_Manufacturing": 1.000002265, "qwen": "Yes"}
{"id": "29990382", "revid": "19502098", "url": "https://en.wikipedia.org/wiki?curid=29990382", "title": "Backdrive", "text": "A backdrive is a component used in reverse to obtain its input from its output. This extends to many concepts and systems from thought based to practical mechanical applications.\nNot every system can be backdriven. A DC electrical generator can be implemented by backdriving a DC electric motor, however a worm drive works only in one direction.\nExample: A CNC vertical mill has a vertical lead screw on the Z-axis. A low lead screw pitch (i.e. 5 turns per inch or fewer) means when the driving motor power is removed such as by turning the machine off, the weight of the spindle will cause the lead screw to rotate as the spindle motor falls down. The solution to prevent back-driving is to use a finer (higher) lead screw pitch (i.e. 10tpi or greater) or have a locking mechanism.\nAnother example is the practice to add swivel caster wheels on a mobile robot, so that humans can push away the robot when it comes too close.", "Engineering,_Manufacturing": 0.9980828762, "qwen": "Yes"}
{"id": "47896295", "revid": "6727347", "url": "https://en.wikipedia.org/wiki?curid=47896295", "title": "Digital twin", "text": "A digital twin is a digital representation of an intended or actual real-world physical product, system, or process (a \"physical twin\") that serves as the effectively indistinguishable digital counterpart of it for practical purposes, such as simulation, integration, testing, monitoring, and maintenance. The digital twin has been intended from its initial introduction to be the underlying premise for Product Lifecycle Management and exists throughout the entire lifecycle (create, build, operate/support, and dispose) of the physical entity it represents. Since information is granular, the digital twin representation is determined by the value-based use cases it is created to implement. The digital twin can and does often exist \"before\" there is a physical entity. The use of a digital twin in the creation phase allows the intended entity's entire lifecycle to be modeled and simulated. A digital twin of an existing entity may be used in real-time and regularly synchronized with the corresponding physical system.\nThough the concept originated earlier, the first practical definition of a digital twin originated from NASA in an attempt to improve the physical-model simulation of spacecraft in 2010. Digital twins are the result of continual improvement in the creation of product design and engineering activities. Product drawings and engineering specifications have progressed from handmade drafting to computer-aided drafting/computer-aided design to model-based systems engineering and strict link to signal from the physical counterpart.\nHistory.\nDigital twins were anticipated by David Gelernter's 1991 book \"Mirror Worlds\". The concept and model of the digital twin was first publicly introduced in 2002 by Michael Grieves, at a Society of Manufacturing Engineers conference in Troy, Michigan. Grieves proposed the digital twin as the conceptual model underlying product lifecycle management (PLM).\nThe digital twin concept, which has been known by different names (e.g., \"virtual twin)\", was subsequently called the \"digital twin\" by John Vickers of NASA in a \"2010 Roadmap Report\". The digital twin concept consists of three distinct parts: the physical object or process and its physical environment, the digital representation of the object or process, and the communication channel between the physical and virtual representations. The connections between the physical version and the digital version include information flows and data that includes physical sensor flows between the physical and virtual objects and environments. The communication connection is referred to as the digital thread.\nThe International Council of Systems Engineers (INCOSE) maintains in its Systems Engineering Book of Knowledge (SEBoK) that: \"A digital twin is a related yet distinct concept to digital engineering. The digital twin is a high-fidelity model of the system which can be used to emulate the actual system.\" The evolving US DoD \"Digital Engineering Strategy\" initiative, first formulated in 2018, defines a digital twin as \"an integrated multiphysics, multiscale, probabilistic simulation of an as-built system, enabled by a Digital Thread, that uses the best available models, sensor information, and input data to mirror and predict activities/performance over the life of its corresponding physical twin.\"\nTypes.\nDigital twins are commonly divided into subtypes that sometimes include: \"digital twin prototype\" (DTP), \"digital twin instance\" (DTI), and \"digital twin aggregate\" (DTA). The DTP consists of the designs, analyses, and processes that realize a physical product. The DTP exists before there is a physical product. The DTI is the digital twin of each individual instance of the product once it is manufactured. The DTI is linked with its physical counterpart for the remainder of the physical counterpart's life. The DTA is the aggregation of DTIs whose data and information can be used for interrogation about the physical product, prognostics, and learning. The specific information contained in the digital twins is driven by use cases. The digital twin is a logical construct, meaning that the actual data and information may be contained in other applications.\nCharacteristics.\nDigital twin technologies have certain characteristics that distinguish them from other technologies:\nConnectivity.\nOne of the main characteristics of digital twin technology is its connectivity. The recent development of the Internet of Things (IoT) brings forward numerous new technologies. The development of IoT also brings forward the development of digital twin technology. This technology shows many characteristics that have similarities with the character of the IoT, namely its connective nature. First and foremost, the technology enables connectivity between the physical component and its digital counterpart. The basis of digital twins is based on this connection, without it, digital twin technology would not exist. As described in the previous section, this connectivity is created by sensors on the physical product which obtain data and integrate and communicate this data through various integration technologies. Digital twin technology enables increased connectivity between organizations, products, and customers. For example, connectivity between partners and customers in a supply chain can be increased by enabling members of this supply chain to check the digital twin of a product or asset. These partners can then check the status of this product by simply checking the digital twin.\nServitization is the process of organizations that are adding value to their core corporate offerings through services. In the case of the example of engines, the manufacturing of the engine is the core offering of this organization, they then add value by providing a service of checking the engine and offering maintenance.\nHomogenization.\nDigital twins can be further characterized as a digital technology that is both the consequence and an enabler of the homogenization of data. Due to the fact that any type of information or content can now be stored and transmitted in the same digital form, it can be used to create a virtual representation of the product (in the form of a digital twin), thus decoupling the information from its physical form. Therefore, the homogenization of data and the decoupling of the information from its physical artifact, have allowed digital twins to come into existence. However, digital twins also enable increasingly more information on physical products to be stored digitally and become decoupled from the product itself.\nAs data is increasingly digitized, it can be transmitted, stored and computed in fast and low-cost ways. According to Moore's law, computing power will continue to increase exponentially over the coming years, while the cost of computing decreases significantly. This would, therefore, lead to lower marginal costs of developing digital twins and make it comparatively much cheaper to test, predict, and solve problems on virtual representations rather than testing on physical models and waiting for physical products to break before intervening.\nAnother consequence of the homogenization and decoupling of information is that the user experience converges. As information from physical objects is digitized, a single artifact can have multiple new affordances. Digital twin technology allows detailed information about a physical object to be shared with a larger number of agents, unconstrained by physical location or time. In his white paper on digital twin technology in the manufacturing industry, Michael Grieves noted the following about the consequences of homogenization enabled by digital twins:\nReprogrammable and smart.\nAs stated above, a digital twin enables a physical product to be reprogrammable in a certain way. Furthermore, the digital twin is also reprogrammable in an automatic manner. Through the sensors on the physical product, artificial intelligence technologies, and predictive analytics, A consequence of this reprogrammable nature is the emergence of functionalities. If we take the example of an engine again, digital twins can be used to collect data about the performance of the engine and if needed adjust the engine, creating a newer version of the product. Also, servitization can be seen as a consequence of the reprogrammable nature as well. Manufactures can be responsible for observing the digital twin, making adjustments, or reprogramming the digital twin when needed and they can offer this as an extra service.\nDigital trace making.\nAnother characteristic that can be observed, is the fact that digital twin technologies leave digital traces. These traces can be used by engineers for example, when a machine malfunctions to go back and check the traces of the digital twin, to diagnose where the problem occurred. These diagnoses can in the future also be used by the manufacturer of these machines, to improve their designs so that these same malfunctions will occur less often in the future.\nModularity.\nIn the sense of the manufacturing industry, modularity can be described as the design and customization of products and production modules. By adding modularity to the manufacturing models, manufacturers gain the ability to tweak models and machines. Digital twin technology enables manufacturers to track the machines that are used and notice possible areas of improvement in the machines. When these machines are made modular, by using digital twin technology, manufacturers can see which components make the machine perform poorly and replace these with better fitting components to improve the manufacturing process.\nExamples.\nAn example of digital twins is the use of 3D modeling to create digital companions for the physical objects. It can be used to view the status of the actual physical object, which provides a way to project physical objects into the digital world. For example, when sensors collect data from a connected device, the sensor data can be used to update a \"digital twin\" copy of the device's state in real time. The term \"device shadow\" is also used for the concept of a digital twin. The digital twin is meant to be an up-to-date and accurate copy of the physical object's properties and states, including shape, position, gesture, status and motion.\nA digital twin also can be used for monitoring, diagnostics and prognostics to optimize asset performance and utilization. In this field, sensory data can be combined with historical data, human expertise and fleet and simulation learning to improve the outcome of prognostics. Therefore, complex prognostics and intelligent maintenance system platforms can use digital twins in finding the root cause of issues and improve productivity.\nDigital twins of autonomous vehicles and their sensor suite embedded in a traffic and environment simulation have also been proposed as a means to overcome the significant development, testing and validation challenges for the automotive application, in particular when the related algorithms are based on artificial intelligence approaches that require extensive training data and validation data sets.\nIndustrial use cases.\nManufacturing industry.\nThe physical manufacturing objects are virtualized and represented as digital twin models (avatars) seamlessly and closely integrated in both the physical and cyber spaces. Physical objects and twin models interact in a mutually beneficial manner.\nThe digital twin is disrupting the entire product lifecycle management (PLM), from design, to manufacturing, to service and operations. Nowadays, PLM is very time-consuming in terms of efficiency, manufacturing, intelligence, service phases and sustainability in product design. A digital twin can merge the product physical and virtual space. The digital twin enables companies to have a digital footprint of all of their products, from design to development and throughout the entire product life cycle. Broadly speaking, industries with manufacturing business are highly disrupted by digital twins. In the manufacturing process, the digital twin is like a virtual replica of the near-time occurrences in the factory. Thousands of sensors are being placed throughout the physical manufacturing process, all collecting data from different dimensions, such as environmental conditions, behavioural characteristics of the machine and work that is being performed. All this data is continuously communicating and collected by the digital twin.\nDue to the Internet of Things, digital twins have become more affordable and could drive the future of the manufacturing industry. A benefit for engineers lies in real-world usage of products that are virtually being designed by the digital twin. Advanced ways of product and asset maintenance and management come within reach as there is a digital twin of the real 'thing' with real-time capabilities.\nDigital twins offer a great amount of business potential by predicting the future instead of analyzing the past of the manufacturing process. The representation of reality created by digital twins allows manufacturers to evolve towards ex-ante business practices. The future of manufacturing drives on the following four aspects: modularity, autonomy, connectivity and digital twin. As there is an increasing digitalization in the stages of a manufacturing process, opportunities are opening up to achieve a higher productivity. This starts with modularity and leading to higher effectiveness in the production system. Furthermore, autonomy enables the production system to respond to unexpected events in an efficient and intelligent way. Lastly, connectivity like the Internet of Things, makes the closing of the digitalization loop possible, by then allowing the following cycle of product design and promotion to be optimized for higher performance. This may lead to increase in customer satisfaction and loyalty when products can determine a problem before actually breaking down. Furthermore, as storage and computing costs are becoming less expensive, the ways in which digital twins are used are expanding. Implementation challenges such as data integration, organizational or compliance challenges can hinder the implementation of Digital Twins and its benefits.\nUrban planning and construction industry.\nGeographic digital twins have been popularised in urban planning practice, given the increasing appetite for digital technology in the Smart Cities movement. These digital twins are often proposed in the form of interactive platforms to capture and display real-time 3D and 4D spatial data in order to model urban environments (cities) and the data feeds within them.\nVisualization technologies such as augmented reality (AR) systems are being used as both collaborative tools for design and planning in the built environment integrating data feeds from embedded sensors in cities and API services to form digital twins. For example, AR can be used to create augmented reality maps, buildings, and data feeds projected onto tabletops for collaborative viewing by built environment professionals.\nIn the built environment, partly through the adoption of building information modeling (BIM) processes, planning, design, construction, and operation and maintenance activities are increasingly being digitised, and digital twins of built assets are seen as a logical extension - at an individual asset level and at a national level. In the United Kingdom in November 2018, for example, the Centre for Digital Built Britain published \"The Gemini Principles\", outlining principles to guide development of a \"national digital twin\".\nOne of the earliest examples of a working 'digital twin' was achieved in 1996 during construction of the Heathrow Express facilities at Heathrow Airport's Terminal 1. Consultant Mott MacDonald and BIM pioneer Jonathan Ingram connected movement sensors in the cofferdam and boreholes to the digital object-model to display movements in the model. A digital grouting object was made to monitor the effects of pumping grout into the earth to stabilise ground movements.\nDigital twins have also been proposed as a method to reduce the need for visual inspections of buildings and infrastructure after earthquakes by using unmanned vehicles to gather data to be added to a virtual model of the affected area.\nHealthcare industry.\nHealthcare is recognized as an industry being disrupted by the digital twin technology. The concept of digital twin in the healthcare industry was originally proposed and first used in product or equipment prognostics. With a digital twin, lives can be improved in terms of medical health, sports and education by taking a more data-driven approach to healthcare. The availability of technologies makes it possible to build personalized models for patients, continuously adjustable based on tracked health and lifestyle parameters. This can ultimately lead to a virtual patient, with detailed description of the healthy state of an individual patient and not only on previous records. Furthermore, the digital twin enables individual's records to be compared to the population in order to easier find patterns with great detail. The biggest benefit of the digital twin on the healthcare industry is the fact that healthcare can be tailored to anticipate on the responses of individual patients. Digital twins will not only lead to better resolutions when defining the health of an individual patient but also change the expected image of a healthy patient. Previously, 'healthy' was seen as the absence of disease indications. Now, 'healthy' patients can be compared to the rest of the population in order to really define healthy. However, the emergence of the digital twin in healthcare also brings some downsides. The digital twin may lead to inequality, as the technology might not be accessible for everyone by widening the gap between the rich and poor. Furthermore, the digital twin will identify patterns in a population which may lead to discrimination.\nAutomotive industry.\nThe automobile industry has been improved by digital twin technology. Digital twins in the automobile industry are implemented by using existing data in order to facilitate processes and reduce marginal costs. Currently, automobile designers expand the existing physical materiality by incorporating software-based digital abilities. A specific example of digital twin technology in the automotive industry is where automotive engineers use digital twin technology in combination with the firm's analytical tool in order to analyze how a specific car is driven. In doing so, they can suggest incorporating new features in the car that can reduce car accidents on the road, which was previously not possible in such a short time frame. Digital twins can be built for not just individual vehicles but also the whole mobility system, where humans (e.g., drivers, passengers, pedestrians), vehicles (e.g., connected vehicles, connected and automated vehicles), and traffics (e.g., traffic networks, traffic infrastructures) can seek guidance from their digital twins deployed on edge/cloud servers to actuate real-time decisions.", "Engineering,_Manufacturing": 0.9993232489, "qwen": "Yes"}
{"id": "54008163", "revid": "46127752", "url": "https://en.wikipedia.org/wiki?curid=54008163", "title": "Artificial intelligence in industry", "text": "Industrial artificial intelligence, or industrial AI, usually refers to the application of artificial intelligence to industry. Unlike general artificial intelligence which is a frontier research discipline to build computerized systems that perform tasks requiring human intelligence, industrial AI is more concerned with the application of such technologies to address industrial pain-points for customer value creation, productivity improvement, cost reduction, site optimization, predictive analysis and insight discovery. Although in a dystopian vision of AI applications, intelligent machines may take away jobs of humans and cause social and ethical issues, industry in general holds a more positive view of AI and sees this transformation of economy unstoppable and expects huge business opportunities in this process.\nHistory.\nThe concept of artificial intelligence was initially proposed in the 1940s, and the idea of improving productivity and gaining insights through smart analytics and modelling is not new. Artificial Intelligence and Knowledge-Based systems have been an active research branch of artificial intelligence for the entire product life cycle for product design, production planning, distribution, and field services. E-manufacturing systems and e-factories did not use the term “AI,” but they scale up modeling of engineering systems to enable complete integration of elements in the manufacturing eco-system for smart operation management.\nRecently, to accelerate leadership in AI initiative, the US government launched an official website AI.gov to highlight its priorities in the AI space. There are several reasons for the recent popularity of industrial AI: More affordable sensors and the automated process of data acquisition; More powerful computation capability of computers to perform more complex tasks at a faster speed with lower cost; Faster connectivity infrastructure and more accessible cloud services for data management and computing power outsourcing.\nCategories.\nTechnology alone never creates any business value if the problems in industry are not well studied. The major categories which industrial AI may contribute to include; product and service innovation, process improvement, and insight discovery.\nCloud Foundry service platforms widely embed the artificial intelligent technologies. Cybermanufacturing systems also apply predictive analytics and cyber-physical modeling to address the gap between production and machine health for optimized productivity.\nProduct applications for user value creation.\nIndustrial AI can be embedded to existing products or services to make them more effective, reliable, safer, and to enhance their longevity. The automotive industry, for example, uses computer vision to avoid accidents and enable vehicles to stay in lane, facilitating safer driving. In manufacturing, one example is the prediction of blade life for self-aware band saw machines, so that users will be able to rely on evidence of degradation rather than experience, which is safer, will extend blade life, and build up blade usage profile to help blade selection.\nProcess applications for productivity improvement.\nAutomation is one of the major aspects in process applications of industrial AI. With the help of AI, the scope and pace of automation have been fundamentally changed. AI technologies boost the performance and expand the capability of conventional AI applications. An example is the collaborative robots. Collaborative robotic arms are able to learn the motion and path demonstrated by human operators and perform the same task. AI also automates the process that used to require human participation. An example is the Hong Kong subway, where an AI program decides the distribution and job scheduling of engineers with more efficiency and reliability than human counterparts do.\nAnother aspect of process applications is the modeling large-scale systems. Cybermanufacturing systems are defined as a manufacturing service system that is networked and resilient to faults by evidence-based modeling and data-driven deep learning. Such a system deals with large and usually geographically distributed assets, which is hard to be modeled via conventional individual-asset physics-based model. With machine learning and optimization algorithms, a bottom-up framework considering machine health can leverage large samples of assets and automate the operation management, spare part inventory planning, and maintenance scheduling process.\nInsight applications for knowledge discovery.\nIndustrial AI can also be used for knowledge discovery by identifying insights in engineering systems. In aviation and aeronautics, AI has been playing a vital role in many critical areas, one of which is safety assurance and root cause. NASA is trying to proactively manage risks to aircraft safety by analyzing flight numeric data and text reports in parallel to not only detect anomalies but also relate it to the causal factors. This mined insight of why certain faults happen in the past will shed light on predictions of similar incidents in the future and prevent problems before they occur.\nPredictive and preventive maintenance through data-driven machine learning is also critical in cost reduction for industrial applications. Prognostics and health management (PHM) programs capture the opportunities at the shop floor by modeling equipment health degradation.\nChallenges.\nThe challenges of industrial AI to unlock the value lies in the transformation of raw data to intelligent predictions for rapid decision-making. In general, there are four major challenges in realizing industrial AI: data, speed, fidelity, and interpretability.\nEngineering systems now generate a lot of data and modern industry is indeed a big data environment. However, industrial data usually is structured, but may be low-quality.\nProduction process happens fast and the equipment and work piece can be expensive, the AI applications need to be applied in real-time to be able to detect anomalies immediately to avoid waste and other consequences. Cloud-based solutions can be powerful and fast, but they still would not fit certain computation efficiency requirements. Edge computing may be a better choice in such scenario.\nUnlike consumer-faced AI recommendations systems which have a high tolerance for false positives and negatives, even a very low rate of false positives or negatives rate may cost the total credibility of AI systems. Industrial AI applications are usually dealing with critical issues related to safety, reliability, and operations. Any failure in predictions could incur a negative economic and/or safety impact on the users and discourage them to rely on AI systems.\nBesides prediction accuracy and performance fidelity, the industrial AI systems must also go beyond prediction results and give root cause analysis for anomalies. This requires that during development, data scientists need to work with domain experts and include domain know-how into the modeling process, and have the model adaptively learn and accumulate such insights as knowledge.", "Engineering,_Manufacturing": 0.9999768734, "qwen": "Yes"}
{"id": "1260106", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1260106", "title": "Flexure", "text": "A flexure is a flexible element (or combination of elements) engineered to be compliant in specific degrees of freedom. Flexures are a design feature used by design engineers (usually mechanical engineers) for providing adjustment or compliance in a design.\nFlexure types.\nMost compound flexure designs are composed of 3 fundamental types of flexure:\nSince single flexure features are limited both in travel capability and degrees of freedom available, compound flexure systems are designed using combinations of these component features. Using compound flexures, complex motion profiles with specific degrees of freedom and relatively long travel distances are possible.\nDesign aspects.\nIn the field of precision engineering (especially high-precision motion control), flexures have several key advantages. High precision alignment tasks might not be possible when friction or stiction are present. Additionally, conventional bearings or linear slides often exhibit positioning hysteresis due to backlash and friction. Flexures are able to achieve much lower resolution limits (in some cases measured in the nanometer scale), because they depend on bending and/or torsion of flexible elements, rather than surface interaction of many parts (as with a ball bearing). This makes flexures a critical design feature used in optical instrumentation such as interferometers.\nDue to their mode of action, flexures are used for limited range motions and cannot replace long-travel or continuous-rotation adjustments. Additionally, special care must be taken to design the flexure to avoid material yielding or fatigue, both of which are potential failure modes in a flexure design.", "Engineering,_Manufacturing": 0.9995983243, "qwen": "Yes"}
{"id": "2326111", "revid": "45430159", "url": "https://en.wikipedia.org/wiki?curid=2326111", "title": "Jockey wheel", "text": "A jockey wheel is a wheel-based mechanical system used for steering or guidance, either:\nOn trailers.\nA jockey wheel for vehicular use is a retractable adjustable-height wheel used on the front of trailers (or caravans) with either a single axle (two running wheels) or more close-coupled axles at or near the centre of gravity whereby without additional support, the trailer would not remain level. The jockey wheel is close to the towing hitch and has a built-in screw jack to enable the trailer nose to be lifted over the tow ball of a car or other powered vehicle. The screw jack can then be used to lower the trailer nose onto the tow ball. Once securely attached to the towing vehicle, the jockey wheel's jacking action is fully retracted for stowage. The jockey wheel can also be unclamped and lifted as far as possible to give the greatest ground clearance before reclamping prior to a journey being made.\nJockey wheels incorporate a castor action, permitting travel in any direction while handling a trailer while it is not attached to a vehicle.\nOn bicycle dérailleurs.\nAlthough variations exist, dérailleurs change the cog or sprocket used on a bicycle's cogset and the jockey wheels take up slack in the bike chain as it is fed from one of the front chainrings. The jockey wheels are held in a cage. This cage holds two guide pulleys that locate the chain, almost always in a vertically positioned S-shaped pattern (an S in reverse when viewed from the bike's drive side). The pulleys are known collectively as the jockey wheels or jockey pulleys - the guide pulley is at the top of the pairing (closest to the sprockets) and the tension pulley is at the bottom.", "Engineering,_Manufacturing": 0.9997497201, "qwen": "Yes"}
{"id": "2326697", "revid": "46040481", "url": "https://en.wikipedia.org/wiki?curid=2326697", "title": "Rotational molding", "text": "Rotational molding (BrE: moulding) involves a heated mold which is filled with a charge or shot weight of the material. It is then slowly rotated (usually around two perpendicular axes), causing the softened material to disperse and stick to the walls of the mold forming a hollow part. In order to form an even thickness throughout the part, the mold rotates at all times during the heating phase, and then continues to rotate during the cooling phase to avoid sagging or deformation. The process was applied to plastics in the 1950s but in the early years was little used because it was a slow process restricted to a small number of plastics. Over time, improvements in process control and developments with plastic powders have resulted in increased use.\nRotocasting (also known as rotacasting), by comparison, uses self-curing or UV-curable resins (as opposed to thermoplastics) in an unheated mould, but shares slow rotational speeds in common with rotational molding. This kind of rotocasting should not be confused with centrifugal casting.\nHistory.\nIn 1855 a patent taken out by R. Peters in Britain documented the first use of a rotating mechanism producing “two centrifugal motions at right angles to each other” by means of beveled gearing, and heat. This rotational molding process was used to create artillery shells and other hollow vessels, the main purpose of which was to create consistency in wall thickness and density. In a U.S. patent in 1905, F.A. Voelke described a method including a polymer for the production of articles using paraffin wax. Development led to G.S. Baker's and G.W. Perks' process of producing hollow chocolate Easter eggs in 1910. Rotational molding had developed further when R.J. Powell made mention of the commonly used ratio of 4:1 between major and minor axes of rotation at slow rotation speeds. His patent covered this process for molding hollow objects from plaster of Paris in the 1920s. These early methods using different materials directed the advances in the way rotational molding is used today with plastics.\nPlastics were introduced to the rotational molding process in the early 1950s. One of the first applications was to manufacture doll heads. The machinery was made of an E Blue box-oven machine, inspired by a General Motors rear axle, powered by an external electric motor and heated by floor-mounted gas burners. The mold was made of electroformed nickel-copper and the plastic was a liquid polyvinyl chloride (PVC) plastisol. The cooling method consisted of placing the mold into cold water. This process of rotational molding led to the creation of other plastic toys. As demand for and popularity of this process increased, it was used to create other products such as road cones, marine buoys, and car armrests. This popularity led to the development of larger machinery. A new system of heating was also created, going from the original direct gas jets to the current indirect high velocity air system. In Europe during the 1960s the Engel process was developed. This allowed large hollow containers to be manufactured in low-density polyethylene. The cooling method consisted of turning off the burners and allowing the plastic to harden while still rocking in the mold.\nIn 1976, the Association of Rotational Moulders (ARM) was started in Chicago as a worldwide trade association. The main objective of this association is to increase awareness of the rotational molding technology and process.\nIn the 1980s, new plastics, such as polycarbonate, polyester, and nylon, were introduced to rotational molding. This has led to new uses for this process, such as the creation of fuel tanks and industrial moldings. The research that has been done since the late 1980s at Queen's University Belfast has led to the development of more precise monitoring and control of the cooling processes based on their development of the “Rotolog system”.\nEquipment and tooling.\nRotational molding machines are made in a wide range of sizes. They normally consist of molds, an oven, a cooling chamber, and mold spindles. The spindles are mounted on a rotating axis, which provides a uniform coating of the plastic inside each mold.\nMolds (or tooling) are either fabricated from welded sheet steel or cast. The fabrication method is often driven by part size and complexity; most intricate parts are likely made with cast tooling. Molds are typically manufactured from stainless steel or aluminum. Aluminum molds are usually much thicker than equivalent steel molds, as it is a softer metal. This thickness does not much affect cycle times because aluminum's thermal conductivity is many times greater than steel's. Owing to the need to develop a model prior to casting, cast molds tend to have additional costs associated with the manufacturing of the tooling, whereas fabricated steel or aluminum molds, particularly when used for less complex parts, are less expensive. However, some molds contain both aluminum and steel. This allows for variable thicknesses in the walls of the product. While this process is not as precise as injection molding, it does provide the designer with more options. The aluminum addition to the steel provides more heat capacity, causing the melt-flow to stay in a fluid state for a longer period.\nStandard setup and equipment for rotational molding.\nNormally all rotation molding systems include molds, oven, cooling chamber and mold spindles. The molds are used to create the part, and are typically made of aluminium. The quality and finish of the product is directly related to the quality of the mold being used. The oven is used to heat the part while also rotating the part to form it as desired. The cooling chamber is where the part is placed until it cools, and the spindles are mounted to rotate and provide a uniform coat of plastic inside each mold.\nRotational molding machines.\nRock and roll machine.\nThis is a specialized machine designed mainly to produce long, narrow parts. Some are of the clamshell type, having one arm, but there are also shuttle-type rock and roll machines, with two arms. Each arm rotates or rolls the mold 360 degrees in one direction and at the same time tips and rocks the mold 45 degrees above or below horizontal in the other direction. Newer machines use forced hot air to heat the mold. These machines are best for large parts that have a large length-to-width ratio. Because of the smaller heating chambers, there is a saving in heating costs compared to biaxial machines.\nClamshell machine.\nThis is a single-arm rotational molding machine. The arm is usually supported by other arms on both ends. The clamshell machine heats and cools the mold in the same chamber. It takes up less space than equivalent shuttle and swing arm rotational molders. It is low in cost compared to the size of products made. It is available in smaller scales for schools interested in prototyping and for high quality models. More than one mold can be attached to the single arm.\nVertical or up & over rotational machine.\nThe loading and unloading area is at the front of the machine between the heating and cooling areas. These machines vary in size between small to medium compared to other rotational machines. Vertical rotational molding machines are energy-efficient, owing to the compactness of their heating and cooling chambers. These machines have the same (or similar) capabilities as the horizontal carousel multi-arm machines, but take up much less space.\nShuttle machine.\nMost shuttle machines have two arms that move the molds back and forth between the heating chamber and cooling station. The arms are independent of each other and they turn the molds biaxially. In some cases, the shuttle machine has only one arm. This machine moves the mold in a linear direction in and out of heating and cooling chambers. It is low in cost for the size of product produced and the footprint is kept to a minimum compared to other types of machines. It is also available in smaller scale for schools and prototyping.\nSwing arm machine.\nThe swing-arm machine can have up to four arms, with a biaxial movement. Each arm is independent from each other as it is not necessary to operate all arms at the same time. Each arm is mounted on a corner of the oven and swings in and out of the oven. On some swing-arm machines, a pair of arms is mounted on the same corner, so that a four-arm machine has two pivot points. These machines are very useful for companies that have long cooling cycles or require a lot of time to demold parts, compared to the cook time. It is much easier to schedule maintenance work or try to run a new mold without interrupting production on the other arms of the machine.\nCarousel machine.\nThis is one of the most common biaxial machines in the industry. It can have up to four arms and six stations and comes in a wide range of sizes. The machine comes in two different models, fixed and independent. A fixed-arm carousel consists of three fixed arms that must move together. One arm will be in the heating chamber while another is in the cooling chamber and the third in the loading/reloading area. The fixed-arm carousel works well when identical cycle times are used for each arm. The independent-arm carousel machine is available with three or four arms that can move independently. This allows for different-size molds, with different cycle times and thickness needs.\nProduction process.\nThe rotational molding process is a high-temperature, low-pressure plastic-forming process that uses heat and biaxial rotation (i.e., angular rotation on two axes) to produce hollow, one-piece parts. Critics of the process point to its long cycle times—only one or two cycles an hour can typically occur, as opposed to other processes such as injection molding, where parts can be made in a few seconds. The process does have distinct advantages. Manufacturing large, hollow parts such as oil tanks is much easier by rotational molding than any other method. Rotational molds are much cheaper than other types of mold. Very little material is wasted using this process, and excess material can often be reused, making it a very economically and environmentally viable manufacturing process.\nThe rotational molding process consists of four distinct phases:\nRecent improvements.\nUntil recently, the process largely relied on both trial and error and the experience of the operator to determine when the part should be removed from the oven and when it was cool enough to be removed from the mold. Technology has improved in recent years, allowing the air temperature in the mold to be monitored and removing much of the guesswork from the process.\nMuch current research is into reducing the cycle time, as well as improving part quality. The most promising area is in mold pressurization. It is well known that applying a small amount of pressure internally to the mold at the correct point in the heating phase accelerates coalescence of the polymer particles during the melting, producing a part with fewer bubbles in less time than at atmospheric pressure. This pressure delays the separation of the part from the mold wall due to shrinkage during the cooling phase, aiding cooling of the part. The main drawback to this is the danger to the operator of explosion of a pressurized part. This has prevented adoption of mold pressurization on a large scale by rotomolding manufacturers.\nMold release agents.\nA good mold release agent (MRA) will allow the material to be removed quickly and effectively. Mold releases can reduce cycle times, defects, and browning of finished product. There are a number of mold release types available; they can be categorized as follows:\nMaterials.\nMore than 80% of all the material used is from the polyethylene family: crosslinked polyethylene (PEX), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE), and regrind. Other compounds are polyvinyl chloride (PVC) plastisols, nylons, and polypropylene.\nOrder of materials most commonly used by industry:\nThese materials are also occasionally used (not in order of most used):\nNatural materials.\nRecently it has become possible to use natural materials in the molding process. Through the use of real sands and stone chip, sandstone composite can be created which is 80% natural non-processed material.\nRotational molding of plaster is used to produce hollow statuettes.\nChocolate is rotationally molded to form hollow treats.\nProducts.\nDesigners can select the best material for their application, including materials that meet U.S. Food and Drug Administration (FDA) requirements. Additives for weather resistance, flame retardation, or static elimination can be incorporated.\nInserts, graphics, threads, handles, minor undercuts, flat surfaces without draft angles, or fine surface detail can be part of the design. Designs can also be multi-wall, either hollow or foam filled.\nProducts that can be manufactured using rotational molding include storage tanks, furniture, road signs and bollards, planters, pet houses, toys, bins and refuse containers, doll parts, road cones, footballs, helmets, canoes, rowing boats, tornado shelters, kayak hulls, underground cellars for vine and vegetables storage and playground slides. The process is also used to make highly specialised products, including UN-approved containers for the transportation of nuclear fissile materials, anti-piracy ship protectors, seals for inflatable oxygen masks and lightweight components for the aerospace industry.\nDesign considerations.\nDesigning for rotational molding.\nAnother consideration is in the draft angles. These are required to remove the piece from the mold. On the outside walls, a draft angle of 1° may work (assuming no rough surface or holes). On inside walls, such as the inside of a boat hull, a draft angle of 5° may be required. This is due to shrinkage and possible part warping.\nAnother consideration is of structural support ribs. While solid ribs may be desirable and achievable in injection molding and other processes, a hollow rib is the best solution in rotational molding. A solid rib may be achieved byinserting a finished piece in the mold, but this adds cost.\nRotational molding excels at producing hollow parts. However, care must be taken when this is done. When the depth of the recess is greater than the width there may be problems with even heating and cooling. Additionally, enough room must be left between the parallel walls to allow for the melt-flow to move properly throughout the mold. Otherwise webbing may occur. A desirable parallel wall scenario would have a gap at least three times the nominal wall thickness, with five times the nominal wall thickness being optimal. Sharp corners for parallel walls must also be considered. With angles of less than 45° bridging, webbing, and voids may occur.\nMaterial limitations and considerations.\nAnother consideration is the melt-flow of materials. Certain materials, such as nylon, will require larger radii than other materials. The stiffness of the set material may be a factor. More structural and strengthening measures may be required when a flimsy material is used.\nWall thickness.\nOne benefit of rotational molding is the ability to experiment, particularly with wall thicknesses. Cost is entirely dependent on wall thickness, with thicker walls being costlier and more time-consuming to produce. While the wall can have nearly any thickness, designers must remember that the thicker the wall, the more material and time will be required, increasing costs. In some cases, the plastics may degrade owing to extended periods at high temperature. Different materials have different thermal conductivity, meaning they require different times in the heating chamber and cooling chamber. Ideally, the part will be tested to use the minimum thickness required for the application. This minimum will then be established as a nominal thickness.\nFor the designer, while variable thicknesses are possible, a process called stop rotation is required. This process is limited in that only one side of the mold may be thicker than the others. After the mold is rotated and all the surfaces are sufficiently coated with the melt-flow, the rotation stops and the melt-flow is allowed to pool at the bottom of the mold cavity.\nWall thickness is important for corner radii as well. Large outside radii are preferable to small radii. Large inside radii are also preferable to small inside radii. This allows for a more even flow of material and a more even wall thickness. However, an outside corner is generally stronger than an inside corner.\nProcess: advantages, limitations, and material requirements.\nAdvantages.\nRotational molding offers design advantages over other molding processes. With proper design, parts assembled from several pieces can be molded as one part, eliminating high fabrication costs. The process also has inherent design strengths, such as consistent wall thickness and strong outside corners that are virtually stress-free. For additional strength, reinforcing ribs can be designed into the part. Along with being designed into the part, they can be added to the mold.\nThe ability to add prefinished pieces to the mold alone is a large advantage. Metal threads, internal pipes and structures, and even different colored plastics can all be added to the mold prior to the addition of plastic pellets. However, care must be taken to ensure that minimal shrinkage while cooling will not damage the part. This shrinking allows for mild undercuts and negates the need for ejection mechanisms (for most pieces).\nRotational molding can be used as a feasible alternative to blow molding with products such as plastic bottles and cylindrical containers. This substitution is efficient on only a smaller scale, as blow-molding's efficiency depends on large runs.\nAnother advantage lies in the molds themselves. Since they require less tooling, they can be manufactured and put into production much more quickly than other molding processes. This is especially true for complex parts, which may require large amounts of tooling for other molding processes. Rotational molding is also the process of choice for short runs and rush deliveries. The molds can be swapped quickly or different colors can be used without purging the mold. With other processes, purging may be required to swap colors.\nDue to the uniform thicknesses achieved, large stretched sections are nonexistent, which makes large thin panels possible (although warping may occur). Also, there is little flow of plastic (stretching) but rather a placing of the material within the part. These thin walls also limit cost and production time.\nAnother cost advantage with rotational molding is the minimal amount of material wasted in production. There are no sprues or runners (as in injection molding), and no off-cuts or pinch-off scrap (as in blow molding). What material is wasted, as scrap or from failed part testing, can usually be recycled.\nLimitations.\nRotation-molded parts are subject to restrictions that are different from those of other plastic processes. As it is a low-pressure process, sometimes designers face hard-to-reach areas in the mold. Good-quality powder may help overcome some situations, but usually the designers have to keep in mind that it is not possible to make sharp threads that would be possible with injection molding. Some products based on polyethylene can be put in the mold before it is charged with the main material. This can help to avoid holes that otherwise would appear in some areas. This could also be achieved using molds with movable sections.\nAnother limitation lies in the molds themselves. Unlike other processes in which only the product needs to be cooled before being removed, with rotational molding the entire mold must be cooled. While water-cooling processes are possible, there is still a large down time of the mold, increasing both financial and environmental costs. Some plastics will degrade with the long heating cycles or in the process of turning them into a powder to be melted.\nThe stages of heating and cooling involve transfer of heat first from the hot medium to the polymer material and next from it to the cooling environment. In both cases, the process of heat transfer occurs in an unsteady regime; therefore, its kinetics attracts the greatest interest in considering these steps. In the heating stage, the heat taken from the hot gas is absorbed both by the mold and the polymer material. The rig for rotational molding usually has a relatively small wall thickness and is manufactured from metals with a high thermal conductivity (aluminum, steel). As a rule, the mold transfers much more heat than plastic can absorb; therefore, the mold temperature must vary linearly. The rotational velocity in rotational molding is rather low (4 to 20 rpm). As a result, in the first stages of the heating cycle, the charged material remains as a powder layer at the bottom of the mold. The most convenient way of changing the cycle is by applying PU sheets in hot rolled forms.\nMaterial requirements.\nOwing to the nature of the process, materials selection must take into account the following:", "Engineering,_Manufacturing": 0.9999934435, "qwen": "Yes"}
{"id": "2327311", "revid": "8280245", "url": "https://en.wikipedia.org/wiki?curid=2327311", "title": "Quality, cost, delivery", "text": "Quality, cost, delivery (QCD), sometimes expanded to quality, cost, delivery, morale, safety (QCDMS), is a management approach originally developed by the British automotive industry. QCD assess different components of the production process and provides feedback in the form of facts and figures that help managers make logical decisions. By using the gathered data, it is easier for organizations to prioritize their future goals. QCD helps break down processes to organize and prioritize efforts before they grow overwhelming.\nQCD is a \"three-dimensional\" approach. If there is a problem with even one dimension, the others will inevitably suffer as well. One dimension cannot be sacrificed for the sake of the other two.\nQuality.\nQuality is the ability of a product or service to meet and exceed customer expectations. It is the result of the efficiency of the entire production process formed of people, material, and machinery. Customer requirements determine the quality scope.\nQuality is a competitive advantage; poor quality often results in bad business. The U.S. business organizations in the 1970s focused more on cost and productivity. That approach led to Japanese businesses capturing a major share of the U.S. market. It was not until the late 1970s and the beginning of the 1980s that the quality factor drastically shifted and became a strategic approach, created by Harvard professor David Garvin. This approach focuses on preventing mistakes and puts a great emphasis on customer satisfaction.\nQuality basis.\nDavid A. Garvin lists eight dimensions of quality:\nProduct components.\nThe quality of a product depends almost entirely on the quality of its raw material. Suppliers and manufacturers must work together to eliminate defects and achieve higher quality. Small and medium-sized enterprises (SMEs) should discuss with their suppliers how quality improvements can affect the overall performance of the supply chain. Quality assurance can reduce testing, scrapping, reworks, and production costs.\nCosts.\nThe biggest costs in most businesses are the four basic types of manufacturing costs:\nIn addition, there are business costs that stay the same, regardless of the production output. Business costs include:\nBusinesses desire to reduce costs to increase their operating profit and bottom line. Cost reduction strategies include:\nDelivery.\nLogistics are an essential part in providing good customer service on time. Logistics customer service can be separated into three elements:\nBenefits.\nQCD offers a method of measuring both simple and complicated business processes. It also represents a basis for comparing businesses: for example, a business measuring a supplier's delivery performance may compare its findings with the business's own performance.\nFlexibility.\nThe \"quality, cost, delivery, and flexibility\" (QCDF) approach, includes flexibility as the capacity to adapt to changes or modifications in the input quality, output quality, product specifications, and delivery schedules.\nProfitability.\nThere are seven measures used to increase profitability.\nNot right first time (NRFT).\nNot getting things right the first time means wasted resources, effort and time. This all leads to excessive costs for the company and poor-quality, high-priced products for the customer. NRFT measures the quality of a product and is expressed in “number of defective parts per million”. The number of defective products is divided by the total quantity of finished products. This figure is then multiplied by 10^6 to get the number of defective parts per million.\nNRFT can be measured internally (defective parts identified within the production process) or externally (defective parts identified outside the production process (e.g. by the supplier or the customer).\nDelivery schedule achievement (DSA).\nDSA analyses how well a supplier delivers what the customer wants and when they want it. The goal is to achieve 100% on-time delivery without any special deliveries or overtime payments, which only increase the delivery cost. DSA measures the actual delivery performance against the planned delivery schedule.\nFailed deliveries include:\nPeople productivity (PP).\nPP is measured by the time it takes (in staff hours) to produce a good-quality product. Obtaining high PP is only possible when:\nStock turns (ST).\nThe ST ratio shows how quickly a company turns raw materials into finished, ready-to-be-sold products. The quicker the better. A low ST means that the money is tied up in stock, and the company has fewer funds to invest in other parts of its business.\nThe OEE shows how well a company uses its equipment and staff.\nOEE is calculated on the base of three elements:\nValue added per person (VAPP).\nVAPP shows how well people are used to turn raw materials into finished goods. In order to calculate VAPP, three things need to be taken into account:\nFloor space utilisation (FSU).\nFSU measures the sales revenue generated by a square meter of factory floor space. Usually to achieve higher FSU the floor space has to be reduced. That means eliminating inventory and reducing the necessary space to a minimum.", "Engineering,_Manufacturing": 0.9898133278, "qwen": "Yes"}
{"id": "22119730", "revid": "1171085356", "url": "https://en.wikipedia.org/wiki?curid=22119730", "title": "List of Harley-Davidson motorcycles", "text": "A list of motorcycles produced under the Harley-Davidson brand.\nAermacchis sold as Harley-Davidsons.\nAermacchi motorcycles sold in US with Harley-Davidson badging. ", "Engineering,_Manufacturing": 0.9997349381, "qwen": "Yes"}
{"id": "22120822", "revid": "869314", "url": "https://en.wikipedia.org/wiki?curid=22120822", "title": "Armored Trunk Manufacturing Company", "text": "Founded in 1920 by Louis Knell, the Youngstown, Ohio-based Armored Trunk Manufacturing Company was one of America's largest manufacturers of steamers, trunks and luggage. During the Dust Bowl, Armored relocated west to Los Angeles, California where the company developed a reputation for building quality products to protect belongings while in transit.\nDuring war times, Armored built footlockers for troops traveling overseas. With the introduction of commercial airline travel, Armored grew into one of the largest footlocker and luggage manufacturers in the country, utilizing its Los Angeles-based factory to produce goods, with New York City sales and distribution office serving some of the biggest national chains.\nThrough the 1980s, Armored introduced specialty luggage packages such as its proprietary brands Alfredo Fettuccini, Sports Network and Luggage Set in a Box and through the licensing of key brands such as Budweiser, Charles Schulz's Snoopy and Friends and the 1984 Olympic Team USA. Sales surged as Armored became the largest luggage and trunk manufacturer west of the Mississippi River.\nIn 1994, after much resistance to the changing marketplace for cheap imported goods, Armored Trunk Manufacturing Company sold its trunk manufacturing production line to Seward Trunk Company. Seward was subsequently purchased by Mercury Luggage Co. of Jacksonville, Florida forming the largest manufacturer of luggage and trunks in the United States.\nAfter the divestiture of the trunk manufacturing production line, Armored focussed on its specialty line, Innerspace Cases, a manufacturer of ATA-style, custom protective road cases.\nExternal links.\n ", "Engineering,_Manufacturing": 0.9996581078, "qwen": "Yes"}
{"id": "353763", "revid": "42069556", "url": "https://en.wikipedia.org/wiki?curid=353763", "title": "Moldmaker", "text": "A moldmaker (mouldmaker in English-speaking countries other than the US) or molder is a skilled tradesperson who fabricates molds for use in casting metal products. \nMoldmakers are generally employed in foundries, where molds are used to cast products from metals such as aluminium and cast iron.\nInjection molding.\nThe term moldmaker may also be used to describe workers employed in fabricating dies and metal moulds for use in injection molding and die-casting, such as in the plastics, rubber or ceramics industries, in which case it is sometimes regarded as a variety of the trade of the toolmaker. The process of manufacturing molds is now often highly automated.\nWhile much of the machining processes involved in mold making use computer-controlled equipment for the actual manufacturing of molds (particularly plastic and rubber injection and transfer). Moldmaking is still a highly skilled trade requiring expertise in manual machining, CNC machining, CNC wire EDM, CNC Ram EDM, surface grinding, hand polishing and more. Because of the high skill and intense labor involved much of the mold making in the US has been outsourced to low wage countries.\nThe majority of plastic and rubber parts that are in existence today are made using injection or transfer molds, requiring a mold to be manufactured by a moldmaker.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "355128", "revid": "1165389089", "url": "https://en.wikipedia.org/wiki?curid=355128", "title": "Hobbing", "text": "Hobbing is a machining process for gear cutting, cutting splines, and cutting sprockets using a hobbing machine, a specialized milling machine. The teeth or splines of the gear are progressively cut into the material (such as a flat, cylindrical piece of metal or thermoset plastic) by a series of cuts made by a cutting tool called a hob.\nHobbing is relatively fast and inexpensive compared to most other gear-forming processes and is used for a broad range of parts and quantities. Hobbing is especially common for machining spur and helical gears.\nA type of skiving that is analogous to the hobbing of external gears can be applied to the cutting of internal gears, which are skived with a rotary cutter (rather than shaped or broached).\nProcess.\nHobbing can create gears that are straight, helical, straight bevel, faced, crowned, wormed, cylkro and chamfered. A hobbing machine uses two skew spindles. One is mounted with a blank workpiece and the other holds the cutter (or “hob”). The angle between the hob's spindle (axis) and the workpiece's spindle varies depending on the type part being manufactured. For example, if a spur gear is being produced, the spindle is held at the lead angle of the hob, whereas if a helical gear is being produced, the held at the lead angle of the hob plus the helix angle of the helical gear. The speeds of the two spindles are held at a constant proportion determined by the number of teeth being cut into the blank; for example, for a single-threaded hob with a gear ratio of 40:1 the hob rotates 40 times to each turn of the blank, producing 40 teeth in the blank. If the hob has multiple threads, the speed ratio is multiplied by the number of threads on the hob. The hob is then fed up into the workpiece until the correct tooth depth is obtained. To finish the operation, the hob is fed through the workpiece parallel to the blank's axis of rotation.\nOften during mass production, multiple blanks are stacked using a suitable fixture and cut in one operation.\nFor very large gears, the blank may be preliminarily gashed to a rough shape to make hobbing more efficient.\nEquipment.\nHobbing machines, also known as \"hobbers\", come in many sizes to produce different sizes of gears. Tiny instrument gears are produced on small table-top machines, while large-diameter marine gears are produced on large industrial machines. A hobbing machine typically consists of a chuck and tailstock to hold the workpiece, a spindle to mount the hob, and a drive motor.\nFor a tooth profile which is theoretically involute, the fundamental rack is straight-sided, with sides inclined at the pressure angle of the tooth form, with flat top and bottom. The necessary addendum correction to allow the use of small-numbered pinions can either be obtained by suitable modification of this rack to a cycloidal form at the tips, or by hobbing at a diameter other than the theoretical pitch. Since the gear ratio between hob and blank is fixed, the resulting gear will have the correct pitch on the pitch circle but the tooth thickness will not be equal to the space width.\nHobbing machines are characterized by the largest module or pitch diameter it can generate. For example, a capacity machine can generate gears with a 10 in pitch diameter and usually a maximum of a 10 in face width. Most hobbing machines are vertical hobbers, meaning the blank is mounted vertically. Horizontal hobbing machines are usually used for cutting longer workpieces; i.e. cutting splines on the end of a shaft.\nThe hob.\nThe \"hob\" is a cutting tool used to cut the teeth into the workpiece. It is cylindrical in shape with helical cutting teeth. These teeth have grooves that run the length of the hob, which aid in cutting and chip removal. There are also special hobs designed for special gears such as the spline and sprocket gears.\nThe cross-sectional shape of the hob teeth are almost the same shape as teeth of a rack gear that would be used with the finished product. There are slight changes to the shape for generating purposes, such as extending the hob's tooth length to create a clearance in the gear's roots. Each hob tooth is relieved on its back side to reduce friction.\nMost hobs are single-thread hobs, but double-, and triple-thread hobs are used for high production volume shops. Multiple-thread hobs are more efficient but less accurate than single-thread hobs.\nDepending on type of gear teeth to be cut, there are custom made hobs and general purpose hobs. Custom made hobs are different from other hobs as they are suited to make gears with modified tooth profiles. Modified tooth profiles are usually used to add strength and reduce size and gear noise.\nCommon types of hobs include:\nUses.\nHobbing is used to make the following types of finished gears:\nHobbing is used to produce most throated worm wheels, but certain tooth profiles cannot be hobbed. If any portion of the hob profile is perpendicular to the axis, the hob will not have the cutting clearance generated by the usual backing off process and will not cut well.\nCycloidal forms.\nFor cycloidal gears (as used in BS978-2 Specification for fine pitch gears) and cycloidal-type gears, each module, ratio, and number of teeth in the pinion requires a different hobbing cutter, so the hobbing is ineffective for small-volume production.\nTo circumvent this problem, a special war-time emergency circular arc gear standard was produced giving a series of close-to-cycloidal forms which could be cut with a single hob for each module for eight teeth and upwards to economize on cutter manufacturing resources. A variant on this is still included in BS978-2a (Gears for instruments and clockwork mechanisms. Cycloidal type gears. Double circular arc type gears).\nTolerances of concentricity of the hob limit the lower modules which can be cut practically by hobbing to about 0.5 module.\nHistory.\nChristian Schiele of Lancaster England patented the hobbing machine in 1856. It was a simple design, but the rudimentary components are all present in the customary patent drawings. The hob cutting tool and the gear train to provide the appropriate spindle speed ratio are clearly visible. Knowledge of hobbing within the watchmaking trade likely precedes his patent.", "Engineering,_Manufacturing": 0.9999878407, "qwen": "Yes"}
{"id": "46947070", "revid": "36529075", "url": "https://en.wikipedia.org/wiki?curid=46947070", "title": "Centrifuge casting", "text": "Centrifugal casting, also commonly known as spin casting, is typically used for industrial manufacturing of cast parts. It was the work of A. G. Eckhardt in 1809 to develop a patent showing the basic principles involved with the process. Centrifugal casting is one of the few casting processes that can be used both to manufacture metals as well as plastic parts. Parts ranging from belt buckles, medallions, figurines, and souvenirs to \"pot metal\" gears and machine parts, bushings, and concrete expansion fasteners are usually manufactured using this process. Spin casting or centrifugal casting is considered to be a relatively inexpensive process ranging to a total cost of no more than a $20,000 investment requirement, in comparison to a process such as investment molding that costs a lot more (usually millions). Centrifugal casting is a popular process for the petrochemical market, defense market, and virtually any other market who needs good quality products at a low manufacturing cost.\nProcess variants.\nCentrifugal casting is a metal casting technique that uses the forces of centripetal acceleration to distribute the molten material in the mold. Molten metal is typically fed into the mold using a spout. The process is then completed using rollers that rotate the mold about its axis causing the liquid metal to form to the mold and harden as the rotation continues. Rotation speeds and pouring rates are specific to the material being used and the design specifications. The true centrifugal casting technique can be performed using both vertical as well as horizontal rotation. The vertical rotation technique is generally used for the smaller parts whereas the longer parts are formed using the horizontal technique.\nHorizontal.\nThe horizontal method is utilized for castings that have a much larger length than diameter and a cylindrical bore in the center. Complex shapes are not obtainable through this process; however, this process is very useful for making things such as piping and tubing. The trouble with this process is the slip that occurs between the metal and the mold as the mold rotates, causing the metal to move slower than the mold.\nVertical.\nThis method is usually used to cast parts in which the diameter exceeds the length. Vertical casting can produce both cylindrical and non-cylindrical castings. These non-cylindrical castings include ball valve balls, gear blanks, and conical shaped parts. Unlike the horizontal method, no slip occurs between the metal and mold due to the constant resultant force applied during rotation.\nSemi-centrifugal.\nSemi-centrifugal casting is a variant of centrifugal casting. The main difference being that the mold is completely filled during the process through the use of a central sprue. If a central bore is required in the casting, a dry sand core is best suited. This process can be completed using either permanent or, the more popular, sand molds. The rotational symmetry produced by this process make it ideal for objects such rail car wheels and pulleys.\nDesign considerations.\nMany factors go into the design of a centrifugal casting process. The desired size and shape of the finished product govern whether the horizontal or vertical method should be used. In addition, the type of material used and the desired dimensions aid in deciding the correct rotation speed and pouring flow rate. In order to compensate for the extreme weight of the metal and the forces exerted by rotation, the apparatus needs to have a sturdy foundation to ensure quality and safety.\nFeatures.\nGeometric capabilities.\nCentrifugal casting is not capable of producing complex geometry. However, the variations in the processes allow for different geometric capabilities. For instance, the horizontal method mainly produces piping whereas the vertical method can produce parts as complex as a propeller.\nSurface finishing.\nThe method produces finished products that have a smooth surface finish. This can be obtained as the die of this kind of process is usually that of a smooth finish and not an uneven or a sand like material. The centrifugal action of the process results in the material having very fine grain on the outer surface. Quality castings with good dimensional accuracy can be produced with this process.", "Engineering,_Manufacturing": 0.9997066259, "qwen": "Yes"}
{"id": "49245420", "revid": "42522270", "url": "https://en.wikipedia.org/wiki?curid=49245420", "title": "Multi-material injection molding", "text": "Multi-material injection molding (MMM) is the process of molding two or more different materials into one plastic part at one time. As is the case in traditional injection molding, multi material injection molding uses materials that are at or near their melting point so that the semi-liquidous (viscous) material can fill voids and cavities within a pre-machined mold, thus taking on the desired shape of designed tooling. In general, advantages of MMM over other production techniques include, but are not limited to, creating parts that have an elastic modulus that varies with location on the part (different regional polymer hardness), creating a single-structure part with different regional materials (similar to the previous advantage, but more focused on joining different types of polymers like rubber and plastic), and also creating a single part with multiple independent polymer colors. Applications range from simple household items like a toothbrush to more heavy duty construction of items like power tools.\nThe three most widely used methods of MMM fabrication are:\nEach MMM primary subset can also be further subdivided into secondary and tertiary subsets, and even further in some cases. This can be advantageous when fine tuning or other general calibration of a specific MMM process is desired. Each primary subset is outlined further in the following sections.\nMulti-component injection molding.\nAlso referred to as co-injection molding, multi-component injection molding describes insertion of multiple viscous materials injected simultaneously, as opposed to placing one material as an additional layer relative to another. In other words, it creates a sandwich-like structure where both materials mold around each other as dissimilar liquids, and exist in such a state at the same time. Relative to the part center, materials can be injected concentrically using the same mold/gate, or regionally using gates at different locations.\nMulti-shot injection molding (MSM).\nAlso referred to as sequential injection molding, multi-shot injection molding refers to creation of multiple layers relative to the starting axis of the initial mold. In other words, the warm, heated materials are inserted into the mold in a very specific sequence one after another. This creates a layering effect between materials while maintaining relatively high-energy interactions at material boundaries. This is important because it implies that the inter-layer bonds are stronger in many cases than when the layers are applied to a previously cooled part, as is more closely the case of over molding. While there are other applications, this operation is preferred when varying molds (different geometries) are desired between material layers.\nOver-molding.\nOver molding is effectively the use of layering effects in polymer application techniques. This process is centered around the use of a liquidous resin to add additional layers of shape and structure to an existing component. An example of such a resin could be a polymer that has been heated to a temperature just above its glass transition temperature). The existing component to which the resin is being added is often injection molded as well, and may be near its own glass transition temperature. This process works well when layers with varying geometric profiles are desired around a central \"core\" structure.\nBenefits.\nIf the desired object is manufacturable using MMM, it is definitely best to use MMM over traditional injection molding. Some of the key features that makes MMM a better approach are:", "Engineering,_Manufacturing": 0.9999723434, "qwen": "Yes"}
{"id": "49246535", "revid": "43075357", "url": "https://en.wikipedia.org/wiki?curid=49246535", "title": "AP&T", "text": "AP&T AB is an industrial enterprise active in the sheet metal forming industry. It is the parent company for the AP&T Group. The company develops and manufactures complete production systems, automation equipment, presses, tools and services for companies that produce pressed sheet metal parts. Customers are active in the automotive industry and as manufacturers of heat exchangers, ventilation products and roof drainage products. AP&T is headquartered in Ulricehamn, Sweden with production facilities in Ulricehamn, Tranemo and Brescia, Italy through its subsidiary NORDA S.p.A.\nHistory.\nAP&T's roots go back to the early 1960s when two of the three companies forming the basis of AP&T were founded.\nLagan Press.\nBertil Åberg began manufacturing hydraulic presses at his new company Lagan Press in 1963. This enabled him to quickly produce spare parts and styling accessories for the American cars he had formerly imported and sold. He opted not to use mechanical presses because they would make the parts too expensive. Bertil Åberg considered hydraulic presses from Germany, but decided that they were too expensive and complicated. These were the factors underlying Åberg's decision to manufacture his own presses.\nVIBAB.\nAt the same time in the early 1960s, Stig Gunnarson and Janne Merlander founded a small-scale machine shop in Blidsberg. The initial products they produced were rod cutting machines and press tools for various industries. The business, which was initially housed in an old hen house, would later become a successful tool manufacturer called VIBAB (Verktygsindustri i Blidsberg AB).\nTranemo Hydraulmaskiner.\nTwo employees at Lagan Press, Håkan Sallander and Bertil Jonsson, had some ideas about how to achieve more stable hydraulic presses that could perform more operations on the same press table. The company's managing director, Bertil Åberg, was not receptive to their idea, however, so the enterprising employees founded a competing business – Tranemo Hydraulmaskiner – in 1970. The three companies became important in the Swedish sheet metal forming market, and all three of them developed automation products in parallel.\nThree companies become one.\nBertil Åberg sold Lagan Press at the beginning of the 1980s, and it became part of ASEA after a few more years (currently ABB). At this time all three companies, Lagan Press, Tranemo Hydraulmaskiner and VIBAB, were only active locally in the Swedish market.\nWhen the three companies decided to merge into one in 1989 they could venture out into the export market together and offer complete solutions.\nGlobal expansion.\nAP&T's sales tripled in the 1990s. The company founded its own sales and service companies in Germany, the US and Denmark. NORDA, an Italian company, was acquired in 1991, and Talent AB was added in 1994. AP&T founded sales and service companies in 2001 in the United Kingdom and Japan, and the company has been represented in Poland with its own sales and service company since 2007. Its presence in Asia was further reinforced in 2009 when AP&T founded a sales and service company in Shanghai, China.\nThe company celebrated 50 years of operations in 2014, and is currently represented on three continents.\nOperations.\nAP&T supplies the sheet metal forming industry with complete production systems and aftermarket services such as service and spare parts solutions, rebuilds and training. The company manufactures its own automation, presses and tools. \nResearch and development.\nAP&T conducts its own research and development within sheet metal forming, and cooperates with Swedish and international research centers on the development of materials, methods and production systems.", "Engineering,_Manufacturing": 0.9992288351, "qwen": "Yes"}
{"id": "49260321", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=49260321", "title": "Smart manufacturing", "text": "Smart manufacturing is a broad category of manufacturing that employs computer-integrated manufacturing, high levels of adaptability and rapid design changes, digital information technology, and more flexible technical workforce training. Other goals sometimes include fast changes in production levels based on demand, optimization of the supply chain, efficient production and recyclability. In this concept, as smart factory has interoperable systems, multi-scale dynamic modelling and simulation, intelligent automation, strong cyber security, and networked sensors.\nThe broad definition of smart manufacturing covers many different technologies. Some of the key technologies in the smart manufacturing movement include big data processing capabilities, industrial connectivity devices and services, and advanced robotics.\nBig data processing.\nSmart manufacturing utilizes big data analytics, to refine complicated processes and manage supply chains. Big data analytics refers to a method for gathering and understanding large data sets in terms of what are known as the three V's, velocity, variety and volume. Velocity informs the frequency of data acquisition, which can be concurrent with the application of previous data. Variety describes the different types of data that may be handled. Volume represents the amount of data. Big data analytics allows an enterprise to use smart manufacturing to predict demand and the need for design changes rather than reacting to orders placed.\nSome products have embedded sensors, which produce large amounts of data that can be used to understand consumer behavior and improve future versions of the product.\nAdvanced robotics.\nAdvanced industrial robots, also known as smart machines, operate autonomously and can communicate directly with manufacturing systems. In some advanced manufacturing contexts, they can work with humans for co-assembly tasks. By evaluating sensory input and distinguishing between different product configurations, these machines are able to solve problems and make decisions independent of people. These robots are able to complete work beyond what they were initially programmed to do and have artificial intelligence that allows them to learn from experience. These machines have the flexibility to be reconfigured and re-purposed. This gives them the ability to respond rapidly to design changes and innovation, which is a competitive advantage over more traditional manufacturing processes. An area of concern surrounding advanced robotics is the safety and well-being of the human workers who interact with robotic systems. Traditionally, measures have been taken to segregate robots from the human workforce, but advances in robotic cognitive ability have opened up opportunities, such as cobots, for robots to work collaboratively with people.\nCloud computing allows large amounts of data storage or computational power to be rapidly applied to manufacturing, and allow a large amount of data on machine performance and output quality to be collected. This can improve machine configuration, predictive maintenance, and fault analysis. Better predictions can facilitate better strategies for ordering raw materials or scheduling production runs.\n3D printing.\nAs of 2019, 3D printing is mainly used in rapid prototyping, design iteration, and small-scale production. Improvements in speed, quality, and materials could make it useful in mass production and mass customization.\nHowever, 3D printing developed so much in recent years that it is no longer used just as technology for prototyping. 3D printing sector is moving beyond prototyping especially it is becoming increasingly widespread in supply chains. The industries where digital manufacturing with 3D printing is the most seen are automotive, industrial and medical. In the auto industry, 3D printing is used not only for prototyping but also for the full production of final parts and products. 3D printing has also been used by suppliers and digital manufacturers coming together to help fight COVID-19.\n3D printing allows to prototype more successfully, thus companies are saving time and money as significant volumes of parts can be produced in a short period. There is great potential for 3D printing to revolutionise supply chains, hence more companies are using it. The main challenge that 3D printing faces is the change of people's mindset. Moreover, some workers will need to re-learn a set of new skills to manage 3D printing technology.\nEliminating workplace inefficiencies and hazards.\nSmart manufacturing can also be attributed to surveying workplace inefficiencies and assisting in worker safety. Efficiency optimization is a huge focus for adopters of \"smart\" systems, which is done through data research and intelligent learning automation. For instance operators can be given personal access cards with inbuilt Wi-Fi and Bluetooth, which can connect to the machines and a Cloud platform to determine which operator is working on which machine in real time. An intelligent, interconnected 'smart' system can be established to set a performance target, determine if the target is obtainable, and identify inefficiencies through failed or delayed performance targets. In general, automation may alleviate inefficiencies due to human error. And in general, evolving AI eliminates the inefficiencies of its predecessors.\nAs robots take on more of the physical tasks of manufacturing, workers no longer need to be present and are exposed to fewer hazards.\nImpact of Industry 4.0.\nIndustry 4.0 is a project in the high-tech strategy of the German government that promotes the computerization of traditional industries such as manufacturing. The goal is the intelligent factory (Smart Factory) that is characterized by adaptability, resource efficiency, and ergonomics, as well as the integration of customers and business partners in business and value processes. Its technological foundation consists of cyber-physical systems and the Internet of Things.\nThis kind of \"intelligent manufacturing\" makes a great use of: \nEuropean Roadmap \"Factories of the Future\" and German one \"\"Industrie 4.0″\" illustrate several of the action lines to undertake and the related benefits. Some examples are:\nStatistics.\nThe Ministry of Economy, Trade and Industry in South Korea announced on 10 March 2016 that it had aided the construction of smart factories in 1,240 small and medium enterprises, which it said resulted in an average 27.6% decrease in defective products, 7.1% faster production of prototypes, and 29.2% lower cost.", "Engineering,_Manufacturing": 0.9999876022, "qwen": "Yes"}
{"id": "49263973", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=49263973", "title": "Digital manufacturing", "text": "Digital manufacturing is an integrated approach to manufacturing that is centered around a computer system. The transition to digital manufacturing has become more popular with the rise in the quantity and quality of computer systems in manufacturing plants. As more automated tools have become used in manufacturing plants it has become necessary to model, simulate, and analyze all of the machines, tooling, and input materials in order to optimize the manufacturing process. Overall, digital manufacturing can be seen sharing the same goals as computer-integrated manufacturing (CIM), flexible manufacturing, lean manufacturing, and design for manufacturability (DFM). The main difference is that digital manufacturing was evolved for use in the computerized world.\nAs part of Manufacturing USA, Congress and the U.S. Department of Defense established MxD (Manufacturing x Digital), the nation's digital manufacturing institute, to speed adoption of these digital tools.\nThree dimensional modeling.\nManufacturing engineers use 3D modeling software to design the tools and machinery necessary for their intended applications. The software allows them to design the factory floor layout and the production flow. This technique lets engineers analyze the current manufacturing processes and allows them to search for ways to increase efficiency in production before production even begins.\nSimulation.\nSimulation can be used to model and test a system's behavior. Simulation also provides engineers with a tool for inexpensive, fast, and secure analysis to test how changes in a system can affect the performance of that system.\nThese models can be classified into the following:\nApplications of simulation can be assigned to:\nAnalysis.\nDigital manufacturing systems often incorporate optimization capabilities to reduce time, cost, and improve the efficiency of most processes. These systems improve optimization of floor schedules, production planning, and decision making. The system analyzes feedback from production, such as deviations or problems in the manufacturing system, and generates solutions for handling them.\nIn addition, many technologies analyze data from simulations in order to calculate a design that is optimal before it is even built. \nDebate continues on the impact of such systems on the manufacturing workforce. Econometric models have found that each newly installed robot displaces 1.6 manufacturing workers on average. Those models also have forecasted that by 2030 as many as 20 million additional manufacturing jobs worldwide could be displaced due to robotization.\nHowever, other research has found evidence, not of job losses, but of a skills gap. Digital manufacturing is creating hundreds of new data-centric manufacturing jobs — roles like “collaborative robotics technician” and “predictive maintenance systems specialist\" — but not enough available workers with the skills and training necessary to fill them.\nTooling and processes.\nThere are many different tooling processes that digital manufacturing utilizes. However, every digital manufacturing process involves the use of computerized numerical controlled machines (CNC). This technology is crucial in digital manufacturing as it not only enables mass production and flexibility, but it also provides a link between a CAD model and production. The two primary categories of CNC tooling are additive and subtractive. Major strides in additive manufacturing have come about recently and are at the forefront of digital manufacturing. These processes allow machines to address every element of a part no matter the complexity of its shape.\nTypes.\nCloud-based design and manufacturing.\nCloud-Based Design (CBD) refers to a model that incorporates social network sites, cloud computing, and other web technologies to aid in cloud design services. This type of system must be cloud computing-based, be accessible from mobile devices, and must be able to manage complex information. Autodesk Fusion 360 is an example CBD.\nCloud-Based Manufacturing (CBM) refers to a model that utilizes the access to open information from various resources to develop reconfigurable production lines to improve efficiency, reduce costs, and improve response to customer needs. A number of online manufacturing platforms enables users to upload their 3D files for DFM analysis and Manufacture.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "49264006", "revid": "3492060", "url": "https://en.wikipedia.org/wiki?curid=49264006", "title": "Transfer molding", "text": "Transfer molding (BrE: transfer moulding) is a manufacturing process in which casting material is forced into a mold. Transfer molding is different from compression molding in that the mold is enclosed rather than open to the fill plunger resulting in higher dimensional tolerances and less environmental impact. Compared to injection molding, transfer molding uses higher pressures to uniformly fill the mold cavity. This allows thicker reinforcing fiber matrices to be more completely saturated by resin. Furthermore, unlike injection molding the transfer mold casting material may start the process as a solid. This can reduce equipment costs and time dependency. The transfer process may have a slower fill rate than an equivalent injection molding process.\nProcess.\nThe mold interior surfaces may be gel-coated. If desired, the mold is first pre-loaded with a reinforcing fiber matrix or preform. Fiber content of a transfer molded composite can be as high as 60% by volume. The fill material may be a preheated solid or a liquid. It is loaded into a chamber known as the pot. A ram or plunger forces material from the pot into the heated mold cavity. If feed-stock is initially solid, the forcing pressure and mold temperature melt it. Standard mold features such as sprue channels, a flow gate and ejector pins may be used. The heated mold ensures that the flow remains liquid for complete filling. Once filled the mold can be cooled at a controlled rate for optimal thermoset curing.\nVariations.\nThe industry identifies a variety of processes within the transfer molding category. There are areas of overlap and the distinctions between each method may not be clearly defined.\nResin transfer molding.\nResin transfer molding (RTM) uses a liquid thermoset resin to saturate a fiber preform placed in a closed mold. The process is versatile and can fabricate products with embedded objects such as foam cores or other components in addition to the fiber preform.\nVacuum assisted resin transfer molding.\nVacuum assisted transfer molding (VARTM) uses a partial vacuum on one side of a fiber mat to pull the resin in for complete saturation. VARTM uses lower plunger forces which allows molding to be carried out with cheaper equipment. The use of a vacuum may allow the resin to adequately flow and or cure without heating. This temperature independence allows thicker fiber preforms and larger product geometries to be economical. VARTM can produce parts with less porosity than regular transfer molding with a proportional increase in casting strength.\nMicro transfer molding.\nAlso called transfer micromolding, micro transfer molding is a process that uses a mold to form then transfer structures as small as 30 nm onto thin films and microcircuitry. Unlike normal scale transfer molding, the micro form can and is used with metals as well as non metals.\nDefects.\nLimiting defects is key when commercially producing any sort of material. Transfer molding is no exception. For example, voids in a transfer molded parts significantly reduce strength and modulus. There can also be defects when fibers are used around sharp corners. The resin flow can create resin rich zones on the outside of these corners.\nPressure distribution\nThere are several contributing factors to voids in the final product of transfer molding. One is a non uniform pressure distribution among the material being pressed into the mold. In this case the material folds in on itself and generates voids. Another is voids in the resin being forced into the mold beforehand. This may be obvious, but it is a main contributor. Things to be done to limit these molds include pressing the resin in at a high pressure, keeping the fiber distribution uniform, and using a high quality properly degassed base resin.\nSharp corners\nSharp corners are the problems with all mold based manufacturing, including casting. Specifically in transfer molding corners can break fibers that have been placed in the mold and can create voids on the inside of corners. This effect is demonstrated in Figure 3 on the right. The limiting factor in these designs is the inner corner radius. This inner radius limit varies depending on resin and fiber selection, but a rule of thumbs is the radius though be 3 to 5 times the laminate thickness.\nMaterials.\nThe material most commonly used for transfer molding is a thermoset polymer. This type of polymer is easy to mold and manipulate, but upon curing, hardens into a permanent form. For simple homogeneous transfer molded parts, the part is simply made of this plastic substrate. On the other hand, resin transfer molding allows for a composite material to be made by placing a fiber within the mold and subsequently injecting the thermosetting polymer.\nDefects known as voids and dry resin (in the case of resin transfer molding) are possible in transfer molding and often are exacerbated by high viscosity materials. This is because a high viscosity plastic flowing through a thin mold may miss entire vacated areas, leaving air pockets. When air pockets are left in the presence of fiber, this creates a “dry” area, which prevents load from being transferred through the fibers in the dry area.\nMaterials used for the plastic are often polyurethanes or epoxy resins. Both of these are soft and malleable before curing, becoming much harder after setting. Materials used for fibers vary extensively, although common choices are carbon or Kevlar fibers, as well as organic fibers, such as hemp.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "49272814", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=49272814", "title": "Mesoscale manufacturing", "text": "Mesoscale manufacturing is the process of creating components and products in a range of approximately from 0.1mm to 5mm with high accuracy and precision using a wide variety of engineering materials. Mesomanufacturing processes are filling the gap between macro- and micromanufacturing processes and overlaps both of them (see picture). Other manufacturing technologies are nanoscale ( 0.5 mm).\nApplications.\nApplication of mesomanufacturing include electronics, biotechnology, optics, medicine, avionics, communications, and other areas. Specific applications include mechanical watches, and extremely small motors and bearings; lenses for cameras and other micro parts for mobile telephones; micro-batteries, mesoscale fuel cells, microscale pumps, valves, and mixing devices for microchemical reactors; biomedical implants, microholes for fiber optics; medical devices such as stents and valves; mini nozzles for high-temperature jets; mesoscale molds; desktop- or micro-factories, and many others.\nProcesses.\nManufacturing in the mesoscale can be accomplished by scaling down macroscale manufacturing processes or scaling up nanomanufacturing processes. Macroscale techniques like mill and lathe machining have been successful used to create features in the range of 25 µm. Meso Machine tools (mMTs), for example a miniaturized milling machine, is an expansion of using traditional macroscale techniques to manufacture mesoscale products. With the limitation of self-excited vibration of machine tools and fatigue, microassembly and micro- and mesoscale milling are created to improve the maximum stiffness and dynamic operation of the milling process, which improves the overall performance of manufacturing. The development of mMTs has revealed many challenges that are specific to machining at the small scales. These challenges stem from the large influence of grain size at small scales and the necessity of extremely small tolerances for both the machine tools and the measuring tools.\nLaser machining is a traditional technique that uses nanosecond pulses of ultraviolet light to create mesoscale features like holes, fillets, etc. The removal of material during laser machining is proportional to exposure time and therefore this process can be used to create three dimensional features.\nA less traditional technique is to use focused ion beam sputtering (FIB) to remove material. This process involves focusing a beam of ions, for example gallium, to the work piece, causing material to be removed. FIB sputtering has a relatively low rate of material removal and therefore has limited application.\nElectrical discharge machining (EDM) is another subtractive manufacturing process used in the mesoscale. This process requires that electricity be transferred between the tool electrode and the work piece and therefore it can only be used to manufacture materials that conduct electricity. One advantage of EDM is that it can be used on hard materials that do not work well in traditional machining processes, such as titanium.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "43074323", "revid": "37898024", "url": "https://en.wikipedia.org/wiki?curid=43074323", "title": "Toyota K platform", "text": "The Toyota K platform, informally known as the Toyota Camry platform, is a front-wheel-drive automobile platform (also adaptable to four-wheel-drive) that has underpinned various Toyota and Lexus models from the mid-size category upwards since September 1999, starting with the Avalon (XX20). Besides the Camry, the K platform was used on minivans, crossovers and luxury sedans. This platform was larger than the front-wheel-drive MC and New MC platforms, but less upscale than the N and New N platforms designed for rear-wheel drive luxury applications. Starting with the XV70 Toyota Camry (2017), the new K platform (TNGA-K) is part of the Toyota New Global Architecture (TNGA).", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "3168208", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=3168208", "title": "Toyota Motor Engineering & Manufacturing North America", "text": "Toyota Motor Engineering & Manufacturing North America, Inc. (TEMA) is the holding company for Toyota's automobile manufacturing and research and development operations in North America. Although the company still exists for legal purposes, the company is operated as part of Toyota Motor North America.\nTEMA was formed in April 2006 as the result of a merger of Toyota Motor Manufacturing North America (TMMNA) and Toyota Technical Center, U.S.A. (TTC). As part of the \"One Toyota\" initiative, TEMA merged with Toyota Motor Sales, USA (TMS) and Toyota Motor North America, Inc. (TMA), which controlled Toyota’s corporate functions, to form Toyota Motor North America. While the three companies continue to exist in legal name, they operate as one company. \nHistory.\nToyota’s first manufacturing investment in the United States came in 1972 when the company struck a deal with Atlas Fabricators, to produce truck beds in Long Beach, California. The partnership was successful and two years later, Toyota purchased Atlas and renamed it Toyota Auto Body California (TABC) as part of its Toyota Auto Body manufacturing subsidiary. \nIn June 1977, the company established the Toyota Technical Center, U.S.A. (TTC), an engineering design and research and development subsidiary in the town of Ann Arbor, Michigan, not far from Detroit, the center of automobile manufacturing in the United States.\nIn 1984, Toyota would establish with GM a joint-venture vehicle manufacturing plant called NUMMI (New United Motor Manufacturing, Inc.) which would begin assembling the Toyota Corolla in Fremont, California, the first Toyota built in America. Toyota took the lessons it learned from NUMMI and went onto establish the wholly-owned Toyota Motor Manufacturing Kentucky and Toyota Motor Manufacturing Canada plants in 1986. \nAs Toyota prepared to open more plants in 1996, the company created the Toyota Motor Manufacturing North America (TMMNA) subsidiary in Erlanger, Kentucky to oversee all Toyota manufacturing operations in North America. \nTMMNA would merge with the Toyota Technical Center, U.S.A. (TTC) research and development subsidiary in April 2006 to form Toyota Motor Engineering & Manufacturing North America, Inc. (TEMA). \nIn July 2017, as part of the \"One Toyota\" initiative, TEMA merged with Toyota Motor Sales, USA (TMS), and Toyota Motor North America, Inc. (TMA), which controlled Toyota’s corporate functions, to form Toyota Motor North America. While the three companies continue to exist in legal name, they operate as one company, at one headquarters campus in Plano, Texas. \nToyota continues to operate research and design centers in Michigan and in October 2017 opened a new Production Engineering and Manufacturing Center (PEMC) in Georgetown, Kentucky (about an hour from the former headquarters), to serve as the go-between for design and manufacturing.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "3168991", "revid": "34845715", "url": "https://en.wikipedia.org/wiki?curid=3168991", "title": "KLA Corporation", "text": "KLA Corporation is an American capital equipment company based in Milpitas, California. It supplies process control and yield management systems for the semiconductor industry and other related nanoelectronics industries. The company's products and services are intended for all phases of wafer, reticle, integrated circuit (IC) and packaging production, from research and development to final volume manufacturing.\nHistory.\nKLA-Tencor was formed in 1997 through the merger of KLA Instruments and Tencor Instruments, two companies in the semiconductor equipment and yield management systems industry. The merger was intended to create a single source for chip process and diagnostics equipment. KLA Instruments was founded in 1975 by Ken Levy and Bob Anderson, and focused on photomask detection to identify chip defects. KLA later broadened its product line to include wafer inspection, wafer metrology and integrated inspection and analysis software. Tencor was founded in 1976 by Czech scientist and US immigrant Karel Urbanek, along with colleague John Schwabacher. The company initially focused on making precise measurements of semiconductor film layer thickness, and in 1984, developed laser-scanning technology to detect particle and other contamination. The company also developed defect review and data analysis equipment. At the time of the merger, the companies' combined revenue was greater than $1 billion.\nIn February 1998, KLA-Tencor acquired Freiburg, Germany-based Nanopro GmbH, a company that used advanced interferometric technology for wafer shape and thickness measurements. In April, the company acquired Amray, Inc., a Bedford, Massachusetts-based provider of scanning electron microscope (SEM) systems for applications including semiconductor manufacturing. In June, the company acquired San Jose, CA-based VARS, a developer of image archiving and retrieval systems. In November, KLA-Tencor acquired the Quantox line of oxide monitoring products from Solon, Ohio-based measurement and instrument company Keithley Instruments. In December, the company acquired the Ultrapointe subsidiary of Uniphase Corporation.\nIn December 1999, the company acquired Taiwan-based yield analysis software maker ACME Systems.\nIn February 2000, KLA-Tencor acquired Austin, Texas-based Finle Technologies, Inc., a developer of lithography modeling and analysis software. In March, the company acquired Austin, Texas-based advanced process control (APC) software developer Fab Solutions, from parent ObjectSpace.\nIn 2001, the company acquired yield management and process control company Phase Metrics, Inc.\nIn 2004, KLA-Tencor acquired surface inspection system manufacturer Candela Instruments, Inc. and the Wafer Inspection Systems business of Inspex, Inc.\nIn 2006, the company acquired ADE Corporation, a supplier of silicon wafer metrology and related gear.\nIn 2007, KLA-Tencor acquired lithography and plasma etch products manufacturer OnWafer Technologies, temperature monitoring firm SensArray Corporation and process control and metrology company Therma-Wave Corporation.\nIn 2008, the company acquired test and measurement company ICOS Vision Systems Corporation NV, and the Microelectronic Inspection Equipment (MIE) business unit of Vistec Semiconductor Systems, Inc.\nIn 2010, KLA-Tencor acquired technology hardware company Ambios Technology, Inc.\nIn 2014, the company acquired computational lithography and inspection company Luminescent Technologies, Inc.\nIn 2017, the company acquired optical profiling and inspection company Zeta Technologies Co. Ltd.\nIn 2018, KLA-Tencor acquired the Nano Indenter product line from Keysight Technologies. The company also acquired Nanomechanics Inc. and MicroVision.\nIn March 2018, KLA-Tencor announced an agreement to acquire Yavne, Israel-based automated optical inspection equipment vendor Orbotech for approximately $3.4 billion. Orbotech also owned Newport, Wales, UK-based SPTS Technologies Ltd, a manufacturer of etch, PVD and CVD wafer processing equipment for the MEMS, advanced packaging, LED, high-speed RF, and power management devices. \nOn January 10, 2019, KLA-Tencor announced that they were changing their name to KLA Corporation. In February, the company announced that its acquisition of Orbotech was complete. The company's name change took effect in July 2019. In June, KLA announced plans to open a second US headquarters in Ann Arbor, Michigan. The facility was scheduled to open in summer 2021, with plans to host 500-600 new hires, around 50% of whom were to be engineers. The facility would reportedly have a relationship with the University of Michigan and support automotive industry partnerships.\nIn July 2021, the company introduced new inspection products for automotive chips. In November, KLA's new North American headquarters opened in Ann Arbor, Michigan. The facility is 230,000 square feet, and is designed to support 1,000 employees.\nIllegal stock options backdating.\nOn January 2008, KLA paid $65 million to settle allegations that the company and certain executives had illegally backdated stock option grants. The U.S. Securities and Exchange Commission stated that \"KLA dramatically overstated its reported financial results, depriving investors of accurate information about the company's compensation costs and financial performance. It is especially troubling for a public company to engage in such misconduct even after being cautioned that these practices were impermissible.\"\nKLA Foundation.\nKLA Foundation (originally KLA-Tencor Foundation) is the company's philanthropic arm, and was founded in 2000. KLA Foundation supports and benefits the global communities in which KLA employees live, such as donations to the Milpitas school district, the American Red Cross, and Silicon Valley Leadership Group’s Covid-19 Aid Coalition. ", "Engineering,_Manufacturing": 0.9998287559, "qwen": "Yes"}
{"id": "3174561", "revid": "42584677", "url": "https://en.wikipedia.org/wiki?curid=3174561", "title": "Continuous casting", "text": "Continuous casting, also called strand casting, is the process whereby molten metal is solidified into a \"semifinished\" billet, bloom, or slab for subsequent rolling in the finishing mills. Prior to the introduction of continuous casting in the 1950s, steel was poured into stationary molds to form ingots. Since then, \"continuous casting\" has evolved to achieve improved yield, quality, productivity and cost efficiency. It allows lower-cost production of metal sections with better quality, due to the inherently lower costs of continuous, standardised production of a product, as well as providing increased control over the process through automation. This process is used most frequently to cast steel (in terms of tonnage cast). Aluminium and copper are also continuously cast.\nSir Henry Bessemer, of Bessemer converter fame, received a patent in 1857 for casting metal between two counter-rotating rollers. The basic outline of this system has recently been implemented today in the casting of steel strip.\nEquipment and process.\nSteel.\nMolten metal is tapped into the ladle from furnaces. After undergoing any ladle treatments, such as alloying and degassing, and arriving at the correct temperature, the ladle is transported to the top of the casting machine. Usually the ladle sits in a slot on a rotating turret at the casting machine. One ladle is in the 'on-cast' position (feeding the casting machine) while the other is made ready in the 'off-cast' position, and is switched to the casting position when the first ladle is empty.\nFrom the ladle, the hot metal is transferred via a refractory shroud (pipe) to a holding bath called a tundish. The tundish allows a reservoir of metal to feed the casting machine while ladles are switched, thus acting as a buffer of hot metal, as well as smoothing out flow, regulating metal feed to the molds and cleaning the metal (see below). \nUsually a disposable working lining refractory used is called as \"tundish boards\".\nMetal is drained from the tundish through another shroud into the top of an open-base copper mold. The depth of the mold can range from , depending on the casting speed and section size. The mold is water-cooled to solidify the hot metal directly in contact with it; this is the \"primary cooling\" process. It also oscillates vertically (or in a near vertical curved path) to prevent the metal sticking to the mold walls. A lubricant (either powders that melt on contact with the metal, or liquids) is added to the metal in the mold to prevent sticking, and to trap any slag particles—including oxide particles or scale—that may be present in the metal and bring them to the top of the pool to form a floating layer of slag. The shroud is set so the hot metal exits it below the surface of the slag layer in the mold and is thus called a submerged entry nozzle (SEN). In some cases, shrouds may not be used between tundish and mold ('open-pour' casting); in this case, interchangeable metering nozzles in the base of the tundish direct the metal into the moulds. Some continuous casting layouts feed several molds from the same tundish.\nIn the mold, a thin shell of metal next to the mold walls solidifies before the center, and then the molded metal, now called a strand, exits the base of the mold into a spray chamber. The bulk of the metal within the walls of the strand is still molten. The strand is immediately supported by closely spaced, water-cooled rollers which support the walls of the strand against the ferrostatic pressure (compare hydrostatic pressure) of the still-solidifying liquid within the strand. To increase the rate of solidification, the strand is sprayed with large amounts of water as it passes through the spray-chamber; this is the \"secondary cooling\" process. Final solidification of the strand may take place after the strand has exited the spray-chamber.\nIt is here that the design of continuous casting machines may vary. This describes a 'curved apron' casting machine; vertical configurations are also used. In a curved apron casting machine, the strand exits the mold vertically (or on a near vertical curved path) and as it travels through the spray-chamber, the rollers gradually curve the strand towards the horizontal. In a vertical casting machine, the strand stays vertical as it passes through the spray-chamber. Molds in a curved apron casting machine can be straight or curved, depending on the basic design of the machine.\nIn a true horizontal casting machine, the mold axis is horizontal and the flow of steel is horizontal from liquid to thin shell to solid (no bending). In this type of machine, either strand or mold oscillation is used to prevent sticking in the mold.\nAfter exiting the spray-chamber, the strand passes through straightening rolls (if cast on other than a vertical machine) and withdrawal rolls. There may be a hot rolling stand after withdrawal to take advantage of the metal's hot condition to pre-shape the final strand. Finally, the strand is cut into predetermined lengths by mechanical shears or by travelling oxyacetylene torches, is marked for identification, and is taken either to a stockpile or to the next forming process.\nIn many cases the strand may continue through additional rollers and other mechanisms which may flatten, roll or extrude the metal into its final shape.\nDevelopments since the mid 1980s reduced the thicknesses that can be cast, initially to transfer bars of ~50mm thickness, also called thin slabs, and then more recently down to thin strip castings of 2mm thickness. \nCasting machines for aluminium and copper.\nAluminium and copper can be cast horizontally and can be more easily cast into near net shape, especially strip, due to their lower melting temperatures.\nStartup and control of the process.\nStarting a continuous casting machine involves placing a dummy bar (essentially a curved metal beam) up through the spray chamber to close off the base of the mould. Metal is poured into the mould and withdrawn with the dummy bar once it solidifies. It is extremely important that the metal supply afterwards be guaranteed to avoid unnecessary shutdowns and restarts, known as 'turnarounds'. Each time the caster stops and restarts, a new tundish is required, as any uncast metal in the tundish cannot be drained and instead freezes into a 'skull'. Avoiding turnarounds requires the melt shop, including ladle furnaces (if any) to keep tight control on the temperature of the metal, which can vary dramatically with alloying additions, slag cover and deslagging, and the preheating of the ladle before it accepts metal, among other parameters. However, the cast rate may be lowered by reducing the amount of metal in the tundish (although this can increase wear on the tundish), or if the caster has multiple strands, one or more strands may be shut down to accommodate upstream delays. Turnarounds may be scheduled into a production sequence if the tundish temperature becomes too high after a certain number of heats or the service lifetime of a non-replaceable component (i.e., the submerged entry nozzle (SEN) in a thin-slab casting machine) is reached.\nMany continuous casting operations are now fully computer-controlled. Several electromagnetic, thermal, or radiation sensors at the ladle shroud, tundish and mould sense the metal level or weight, flow rate and temperature of the hot metal, and the programmable logic controller (PLC) can set the rate of strand withdrawal via speed control of the withdrawal rolls. The flow of metal into the moulds can be controlled via three methods:\nOverall casting speed can be adjusted by altering the amount of metal in the tundish, via the ladle slide gate. The PLC can also set the mould oscillation rate and the rate of mould powder feed, as well as the flow of water in the cooling sprays within the strand. Computer control also allows vital casting data to be transmitted to other manufacturing centres (particularly the steelmaking furnaces), allowing their work rates to be adjusted to avoid 'overflow' or 'underrun' of product.\nProblems.\nContamination by oxygen.\nWhile the large amount of automation helps produce castings with no shrinkage and little segregation, continuous casting is of no use if the metal is not clean beforehand, or becomes 'dirty' during the casting process. One of the main methods through which hot metal may become dirty is by oxidation, which occurs rapidly at molten metal temperatures (up to 1700 °C for steel); inclusions of gas, slag or undissolved alloys may also be present. To prevent oxidation, the metal is isolated from the atmosphere as much as possible. To achieve this, exposed liquid metal surfaces are covered – by the shrouds, or in the case of the ladle, tundish and mould, by synthetic slag. In the tundish, any inclusions that are less dense than the liquid metal – gas bubbles, other slag or oxides, or undissolved alloys – may also float to the surface and be trapped in the slag layer. While the tundish and mold fill for the first time at the start of a casting run, the liquid is badly contaminated with oxygen and the first items produced are typically quarantined or diverted to customers who do not require top-quality material.\nUpcasting solves this problem by forming a continuous product from a metal (e.g. copper or silver) seed (e.g. metal rod).\nBreakouts.\nA major problem that may occur in continuous casting is \"breakout\" of the liquid metal: for whatever reason, the solid shell of the strand breaks and allows the still-molten metal contained within to spill out and foul the machine. In most industrial environments this event is very costly as it leads to a shutdown of the strand and typically requires an extended turnaround involving removal of the spilled material from within the strand equipment and/or replacement of damaged machinery. A breakout is usually due to the shell wall being too thin to support the liquid column above it, a condition which has several root causes often related to heat management. Improper cooling water flow to the mould or the strand cooling sprays may lead to inadequate heat removal from the solidifying metal, causing the solid shell to thicken too slowly. If the metal withdrawal rate is too fast, the shell may not have time to solidify to the required thickness even with enhanced cooling sprays. Similarly, the incoming liquid metal may be too hot and the final solidification may occur further down the strand at a later point than expected; if this point is below the straightening rolls, the shell may break from stresses applied during straightening. A breakout can also occur as a result of physical irregularities or damage to the shell occurring within the mould during the initial seconds of solidification. Excessive turbulence within the mold may cause an irregular shell pattern that grows abnormally or it may entrap slag droplets within the shell which reduces the wall strength. A common occurrence is for the shell to stick to the mould's surface and tear; modern instrumented molds and computer control systems typically detect this and slow the caster down temporarily to let the wall refreeze and heal while it is still supported in the mould. Should the tear occur near the exit of the mould or be of unexpected severity, the shell may still fail in a breakout once it emerges from the mould wall. If the incoming metal is severely overheated, it may be preferable to stop the caster than to risk a breakout. Additionally, lead contamination of the metal (caused by counterweights or lead-acid batteries in the initial steel charge) can form a thin film between the mould wall and the steel, inhibiting heat removal and shell growth and increasing the risk of breakouts.\nOther considerations.\nAnother problem that may occur is a \"carbon boil\" – oxygen dissolved in the steel reacts with also-present carbon to generate bubbles of carbon monoxide. As the term \"boil\" suggests, this reaction is extremely fast and violent, generating large amounts of hot gas, and is especially dangerous if it occurs in the confined spaces of a casting machine. Oxygen can be removed by \"killing\" it through the addition of silicon or aluminium to the steel, which reacts to form silicon oxide (silica) or aluminium oxide (alumina). However, too much alumina in the steel will clog the casting nozzles and cause the steel to 'choke off'.\nComputational fluid dynamics and other fluid flow techniques are being used extensively in the design of new continuous casting operations, especially in the tundish, to ensure that inclusions and turbulence are removed from the hot metal, yet ensure that all the metal reaches the mould before it cools too much. Slight adjustments to the flow conditions within the tundish or the mould can mean the difference between high and low rejection rates of the product.\nStarter bar.\nThe starter bar, also called a dummy bar, has a free end portion which is flexible for storage and a substantially rigid portion at the end which plugs the mold. The starter bar is constructed in discrete blocks secured to one side of a planar spine provided in segments and arranged end to end. Adjustable spacers in the form of tapered blocks are disposed between the blocks of the bar to allow the starter bar to be self-supporting in a curved configuration corresponding to the casting path. A more flexible spine in the end portion of the starter bar allows the starter bar to be curved to a tighter radius than that of the casting path while the blocks fan out in an unsupported configuration. A storage ramp is provided to support the flexible end in the stored position. Before a cast is started, the starter bars are fed through the caster (in reverse direction of casting) using hydraulic actuators. Once fed all the way to the bottom of the mold, the process of packing the mold can continue to ensure a smooth start up.\nDirect strip casting.\nDirect strip casting is a continuous casting process for producing metallic sheet directly from the molten state that minimizes the need for substantial secondary processing. For low-carbon sheet steels, this is a relatively new process which has only achieved commercial success since the early 2000s.\nTwin-belt continuous casting.\nTwin-belt continuous casting is a continuous casting process that produces high volume continuous metal bar or strip of constant rectangular cross section. Twin-belt continuous casting employs a moving mold consisting of parallel carbon-steel belts held in tension as top and bottom casting surfaces. Chains of rectangular steel or copper blocks moving with the belts and spaced according to the desired cast width form the sides of the mold.\nMolten metal is introduced into the twin-belt continuous casting machine from a tundish through a nozzle placed between the casting belts. The metal is cooled by direct contact with the belts which are in turn cooled by high pressure recirculating water. Various coatings can be applied to the belt casting surfaces to provide required mold interface characteristics and prevent adhesion.\nThe cast metal from the twin-belt continuous casting machine is synchronized with, and directly fed into, a hot rolling mill. Combining the casting and rolling operations can result in significant energy and cost savings over other casting processes which incorporate intermediate cast and reheat steps.\nMetals cast on twin-belt continuous casting machines: Copper (Bar, Strip, Anode), Aluminum(Strip), Zinc (Strip), Lead (Strip)\nProduction rates and speeds: Twin-belt continuous casting rates range up to 60 tons per hour at speeds up to 14 meters per minute.\nTwin-belt continuous casting is a near net shape casting process, which significantly reduces the need for secondary rolling or forming operations. For example, when casting copper anode plate the cast slab is not rolled but rather sheared directly into distinct anode plates.\nThe cooling belts are typically made of low carbon steel and are held under tension within the casting machine to ensure flatness and accuracy. As a \"cold\" belt enters the mold region, it is heated in the cast zone and is subject to powerful forces caused by thermal expansion. When casting wide strip, these forces must be controlled to eliminate buckling and reduce thermal distortion of the belt at the mold entrance. These forces can be controlled by preheating the belts before mold entry, or by magnetically stabilizing them once they have entered the mold.\nBelt preheating: For wide strip casting, a belt preheating system can be used to bring the belt up to 150 °C or higher immediately prior to entering the casting mold, reducing the effects of cold framing. Induction heating coils can be used across the width to preheat each belt. In addition to preventing thermal distortion, the high preheat temperature serves to eliminate any moisture present on the belt surface.\nMagnetic stabilization: When casting wide strip, the tendency of localized thermal distortion can be resisted by the use of high-strength, magnetic belt back-up support rolls within the mold region. The moving belt is held against the support rolls by magnetized rotating fins maintaining the belt in a flat plane.\nWithin the twin-belt continuous casting machine, molten metal progressively solidifies on the mold surfaces as it moves through the mold region, with a sump of molten metal present between the solidifying outer surfaces. Belt coatings, texture, and gas layer modifications are used to fine tune the heat transfer rate from the cast metal to the belt. Full thickness solidification can occur as early as 30% of the way through the mold for thin strip, or up to 2 m beyond the mold exit for large bar where exit water spray cooling and roller support are required.\nClosed pool feeding: When casting certain metals such as aluminum, a fully closed pool “injection” metal feeding system can be employed. Here, the metal is introduced under slight pressure into the closed mold cavity. Metal flow is controlled by maintaining a preset level in the tundish. The feed snout, or nozzle, is typically made from a ceramic material which is thermally stable and permeable to gases being released from the flowing metal.\nOpen pool feeding: When casting other metals, such as copper, zinc and lead, an open pool feeding system is often used. In this case, the upper belt pulley is offset downstream from the bottom pulley. Metal flows through an open trough or tundish into a standing pool of molten metal formed at the convergence of the belts. Shrouding gases may be employed to protect against oxidation.\nMold tapering: The twin-belt casting machine differs from other moving mold casting machines in that all four mold surfaces are independent. This allows the mold surfaces to be tapered to remain in contact with the cast product as it shrinks. The high velocity cooling water, which is continuously applied to the backside of the belt, impinges on the belt and creates a force on the belt. This force acts to press the belt against the surface of the strip or slab as it shrinks, keeping the belt in close contact with the cast product throughout the mold. Each side of the mold is formed by an endless chain of dam blocks, which are held against the cast strip by adjustable spring-loaded guides.\nMolten metal level control: To accommodate high casting speeds and maintain as high a pool level as possible, non-contact electromagnetic metal level indicators can be used to sense the pool level in the casting machine.\nAluminum or copper strip casting: Commercial twin-belt continuous strip casting machines are capable of producing as-cast dimensions from 10–35 mm thick, and up to 2035 mm wide. After being directly fed into a hot rolling mill, the as-cast strip is typically rolled down to 1–3 mm thickness strip.\nCopper bar casting: As-cast dimensions range from 35–75 mm thick, and from 50-150 mm wide. After being directly fed into a hot rolling mill, the as-cast bar is typically rolled into 8 mm diameter rod to be used for wire drawing.\nCopper anode casting: Special dam blocks which contain anode lug molds and a traveling hydraulic shear are added to the twin-belt casting machine to continuously cast net shape copper anodes. Anode width of approximately 1 meter (excluding lugs) and thicknesses from 16 mm to 45 mm. The primary advantage of this process is uniformity of the as-cast anode in terms of size and surface quality. Anodes cast using this process do not require additional preparation after casting.\nMold length:The mold length ranges from approximately 2000 mm for strip casting machines and up to 3700 mm for copper bar casting machines.", "Engineering,_Manufacturing": 0.9999454021, "qwen": "Yes"}
{"id": "141906", "revid": "43283345", "url": "https://en.wikipedia.org/wiki?curid=141906", "title": "Material requirements planning", "text": "Material requirements planning (MRP) is a production planning, scheduling, and inventory control system used to manage manufacturing processes. Most MRP systems are software-based, but it is possible to conduct MRP by hand as well.\nAn MRP system is intended to simultaneously meet three objectives:\nHistory.\nPrior to MRP, and before computers dominated industry, reorder point (ROP)/reorder-quantity (ROQ) type methods like EOQ (economic order quantity) had been used in manufacturing and inventory management.\nMRP was computerized by the aero engine makers Rolls-Royce and General Electric in the early 1950s but not commercialized by them. It was then 'reinvented' to supply the Polaris program and then, in 1964, as a response to the Toyota Manufacturing Program, Joseph Orlicky developed material requirements planning (MRP). The first company to use MRP was Black & Decker in 1964, with Dick Alban as project leader. Orlicky's 1975 book \"Material Requirements Planning\" has the subtitle \"The New Way of Life in Production and Inventory Management\". By 1975, MRP was implemented in 700 companies. This number had grown to about 8,000 by 1981.\nIn 1983, Oliver Wight developed MRP into manufacturing resource planning (MRP II). In the 1980s, Joe Orlicky's MRP evolved into Oliver Wight's manufacturing resource planning (MRP II) which brings master scheduling, rough-cut capacity planning, capacity requirements planning, S&OP in 1983 and other concepts to classical MRP. By 1989, about one third of the software industry was MRP II software sold to American industry ($1.2 billion worth of software).\nThe scope of MRP in manufacturing.\nDependent demand vs independent demand.\nIndependent demand is demand originating outside the plant or production system, while dependent demand is demand for components. The bill of materials (BOM) specifies the relationship between the end product (independent demand) and the components (dependent demand). MRP takes as input the information contained in the BOM.\nThe basic functions of an MRP system include: inventory control, bill of material processing, and elementary scheduling. MRP helps organizations to maintain low inventory levels. It is used to plan manufacturing, purchasing and delivering activities.\n\"Manufacturing organizations, whatever their products, face the same daily practical problem - that customers want products to be available in a shorter time than it takes to make them. This means that some level of planning is required.\"\nCompanies need to control the types and quantities of materials they purchase, plan which products are to be produced and in what quantities and ensure that they are able to meet current and future customer demand, all at the lowest possible cost. Making a bad decision in any of these areas will make the company lose money. A few examples are given below:\nMRP is a tool to deal with these problems. It provides answers for several questions:\nMRP can be applied both to items that are purchased from outside suppliers and to sub-assemblies, produced internally, that are components of more complex items.\nData.\nThe data that must be considered include:\nOutputs.\nThere are two outputs and a variety of messages/reports:\nMessages and reports:\nMethods to find order quantities.\nWell-known methods to find order quantities are:\nMathematical formulation.\nMRP can be expressed as an optimal control problem:\nWhere \"x' \" is local inventory (the state), \"z\" the order size (the control), \"d\" is local demand, \"k\" represents fixed order costs, \"c\" variable order costs, \"h\" local inventory holding costs. δ is the Heaviside function. Changing the dynamics of the problem leads to a multi-item analogue of the dynamic lot-size model.\nProblems with MRP systems.\nSolutions to data integrity issues.\nSource:\nDemand driven MRP.\nIn 2011, the third edition of \"Orlicky's Materials Requirements Planning\" introduced a new type of MRP called \"demand driven MRP\" (DDMRP). The new edition of the book was written, not by Orlicky himself (he died in 1986) but by Carol Ptak and Chad Smith at the invitation of McGraw Hill to update Orlicky's work.\nDemand driven MRP is a multi-echelon formal planning and execution technique with five distinct components:\nThese five components work together to attempt to dampen, if not eliminate, the nervousness of traditional MRP systems and the bullwhip effect in complex and challenging environments. The Demand Driven Institute claims the following: In utilizing these approaches, planners will no longer have to try to respond to every single message for every single part that is off by even one day. This approach provides real information about those parts that are truly at risk of negatively impacting the planned availability of inventory. DDMRP sorts the significant few items that require attention from the many parts that are being managed. Under the DDMRP approach, consultants selling it claim that fewer planners can make better decisions more quickly. That means companies will be better able to leverage their working and human capital as well as the huge investments they have made in information technology. One down-side, however, is that DDMRP cannot run on the majority of MRPII/ERP systems in use today.\nIt is claimed by the companies selling it that DDMRP has been successfully applied to a variety of environments including CTO (configure to order), MTS (make to stock), MTO (make to order) and ETO (engineer to order) although detailed studies are rare. The methodology is applied differently in each environments but the five step process remains the same. DDMRP leverages knowledge from theory of constraints (TOC), traditional MRP & DRP, Six Sigma and lean. It is effectively an amalgam of MRP for planning, and kanban techniques for execution (across multi-echelon supply chains) which means that it has the strengths of both but also the weaknesses of both, so it remains a niche solution. Implementations of Demand Driven MRP began in 2002 and there are now multiple case studies and published peer reviewed journal articles published by the organizations selling it. The problems with MRP (as listed above) also apply to DDMRP.\nAdditional references are included below. ", "Engineering,_Manufacturing": 0.9998528957, "qwen": "Yes"}
{"id": "4148868", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=4148868", "title": "Crash simulation", "text": "A crash simulation is a virtual recreation of a destructive crash test of a car or a highway guard rail system using a computer simulation in order to examine the level of safety of the car and its occupants. Crash simulations are used by automakers during computer-aided engineering (CAE) analysis for crashworthiness in the computer-aided design (CAD) process of modelling new cars. During a crash simulation, the kinetic energy, or energy of motion, that a vehicle has before the impact is transformed into deformation energy, mostly by plastic deformation (plasticity) of the car body material (Body in White), at the end of the impact.\nData obtained from a crash simulation indicate the capability of the car body or guard rail structure to protect the vehicle occupants during a collision (and also pedestrians hit by a car) against injury. Important results are the deformations (for example, steering wheel intrusions) of the occupant space (driver, passengers) and the decelerations (for example, head acceleration) felt by them, which must fall below threshold values fixed in legal car safety regulations. To model real crash tests, today's crash simulations include virtual models of crash test dummies and of passive safety devices (seat belts, airbags, shock absorbing dash boards, etc.). Guide rail tests evaluate vehicle deceleration and rollover potential, as well as penetration of the barrier by vehicles.\nHistory.\nIn the years 1970 attempts were made to simulate car crash events with non-linear spring-mass systems after calibration, which require as input the results of physical destructive laboratory tests, needed to determine the mechanical crushing behavior of each spring component of the modeled system. \"First principle\" simulations like more elaborate finite element models, however, need only the definition of the structural geometry and the basic material properties (rheology of car body steel, glass, plastic parts, etc.) as an input to generate the numerical model.\nThe origins of industrial first principle computerized car crash simulation lies in military defense, outer space, and civil nuclear power plant applications. Upon presentation of a simulation of the accidental crash of a military fighter plane into a nuclear power plant on May 30, 1978, by ESI Group in a meeting organized by the Verein Deutscher Ingenieure (VDI) in Stuttgart, car makers became alerted to the possibility of using this technology for the simulation of destructive car crash tests (Haug 1981).\nIn the following years, German car makers produced more complex crash simulation studies, simulating the crash behavior of individual car body components, component assemblies, and quarter and half car bodies in white (BIW). These experiments culminated in a joint project by the Forschungsgemeinschaft Automobil-Technik (FAT), a conglomeration of all seven German car makers (Audi, BMW, Ford, Mercedes-Benz, Opel, Porsche, and Volkswagen), which tested the applicability of two emerging commercial crash simulation codes. These simulation codes recreated a frontal impact of a full passenger car structure (Haug 1986) and they ran to completion on a computer overnight. Now that turn-around time between two consecutive job-submissions (computer runs) did not exceed one day, engineers were able to better understand the crash behavior and make efficient and progressive improvements to the analyzed car body structure.\nComputer-aided engineering (CAE) software became lately a norm in the crash test simulation. The combination of Machine learning and CAE tools allowed a much better acceleration of the simulation software. Engineers used ML to predict:\nApplication.\nCrash simulations are used to investigate the safety of the car occupants during impacts on the front end structure of the car in a \"head-on collision\" or \"frontal impact\", the lateral structure of the car in a “side collision” or “side impact”, the rear end structure of a car in a \"rear-end collision\" or “rear impact”, and the roof structure of the car when it overturns during a \"rollover\". Crash simulations can also be used to assess injury to pedestrians hit by a car.\nBenefits.\nA crash simulation produces results without actual destructive testing of a new car model. This way, tests can be performed quickly and inexpensively in a computer, which permits optimization of the design before a real prototype of the car has been manufactured. Using a simulation, problems can be solved before spending time and money on an actual crash test. The great flexibility of printed output and graphical display enables designers to solve some problems that would have been nearly impossible without the help of a computer.\nAnalysis.\nLarge number of crash simulations use a method of analysis called the Finite Element Method. The complex problems are solved by dividing a surface into a large but still finite number of elements and determining the motion of these elements over very small periods of time. Another approach to crash simulations is performed by application of Macro Element Method. The difference between two mentioned above methodologies is that the structure in case of Macro Element Method consists of smaller number of elements. The calculation algorithm of structure deformation is based on experimental data rather than calculated from partial differential equations.\nPam-Crash started crash simulation and together with LS-DYNA is a software package which is widely used for application of Finite Element Method. This method allows detailed modeling of a structure, but the disadvantage lies in high processing unit requirements and calculation time. \nThe Visual Crash Studio uses Macro Element Methodology. In comparison with FEM it has some modeling and boundary condition limitations but its application does not require advanced computers and the calculation time is incomparably smaller. Two presented methods complement each other. Macro Element Method is useful at early stage of the structure design process while Finite Element Method performs well at its final stages.\nStructural analysis.\nIn a typical crash simulation, the car body structure is analyzed using spatial discretization, that is, breaking up the continuous movement of the body in real time into smaller changes in position over small, discrete time steps. The discretization involves subdividing the surface of the constituent, thin, sheet metal parts into a large number (approaching one million in 2006) of quadrilateral or triangular regions, each of which spans the area between \"nodes\" to which its corners are fixed. Each element has mass, which is distributed as concentrated masses and as mass moments of inertia to its connecting nodes. Each node has 6 kinematic degrees of freedom, that is, one node can move in three linear directions under translation and can rotate about three independent axes. The spatial coordinates (\"x\"), displacement (\"u\"), velocity (\"v\"), and acceleration (\"a\") of each node is mostly expressed in a three-dimensional rectangular Cartesian coordinate system with axes \"X\",\"Y\", and \"Z\".\nIf the nodes move during a crash simulation, the connected elements move, stretch, and bend with their nodes, which causes them to impart forces and moments to their nodal connections. The forces and moments at the nodes correspond to the inertia forces and moments, caused by their translational (linear) and angular accelerations and to the forces and moments transmitted by the resistance of the structural material of the connected elements as they deform. Sometimes, additional external structural loads are applied, like gravity loads from the self weight of the parts, or added loads from external masses.\nThe forces and moments of all nodes are collected into a column vector (or column matrix), and the time dependent equations of motion (in dynamic equilibrium) can be written as follows.\nwhere vector formula_2 (mass times acceleration vector) collects the inertia forces at the nodes, formula_3 collects the external nodal loads, and formula_4 collects the internal resisting forces from the deformation of the material. \"M\" is a diagonal matrix of the nodal masses. Each vector (\"u\", \"v\", \"a\", \"F\", etc.) has dimension 6 times the total number of nodes in the crash model (about 6 million “degrees of freedom” for every 1 million \"nodes\" in 3-D thin shell finite element models).\nTime analysis.\nA crash simulation uses time discretization as well to separate the continuous changes in time into very small, usable segments. The dynamic equations of motion hold at all times during a crash simulation and must be integrated in time, \"t\", starting from an initial condition at time zero, which is just prior to the crash. According to the explicit finite difference time integration method used by most crash codes, the accelerations, velocities, and displacements of the body are related by the following equations.\nIn these equations the subscripts \"n\"±1/2, \"n\", \"n\"+1 denote past, present, and future times, \"t\", at half and full-time intervals with time steps formula_8 and formula_9, respectively.\nSolution.\nThe above system of linear equations is solved for the accelerations, formula_10, the velocities, formula_11, and the displacements, formula_12, at each discrete point in time, \"t\", during the crash duration. This solution is trivial, since the mass matrix is diagonal. The computer time is proportional to the number of finite elements and the number of solution time steps. The stable solution time step, formula_13, is limited for numerical stability, as expressed by the Courant–Friedrichs–Lewy condition (CFL), which states that “in any time-marching computer simulation, the time step must be less than the time for some significant action to occur, and preferably considerably less.\" In a crash simulation, the fastest significant actions are the acoustic signals that travel inside the structural material.\nThe solid elastic stress wave speed amounts to\nwhere formula_15 is the initial elastic modulus (before plastic deformation) of the material and formula_16 is the mass density. The largest stable time step for a given material is therefore\nwhere formula_18 is the smallest distance between any two nodes of the numerical crash simulation model.\nSince this distance can change during a simulation, the stable time step changes and must be updated continually as the solution proceeds in time. When using steel, the typical value of the stable time step is about one microsecond when the smallest discrete node distance in the mesh of the finite element model is about 5 millimeters. It needs then more than 100,000 time intervals to solve a crash event that lasts for one tenth of a second. This figure is exceeded in many industrial crash models demanding optimized crash solvers with High-Performance Computing (HPC) features, such as vectorization and parallel computing.", "Engineering,_Manufacturing": 0.9999879599, "qwen": "Yes"}
{"id": "1637991", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=1637991", "title": "Shot welding", "text": "Shot welding is a type of spot welding used to join two pieces of metal together. This is accomplished by clamping the two pieces together and then passing a large electric current through them for a short period of time. Shot welding was invented by Earl J. Ragsdale, a mechanical engineer at the Budd Company, in 1932 to weld stainless steel. This welding method was used to construct the \"Pioneer Zephyr\".\nMethod.\nThe E. G. Budd Company of Philadelphia recognized the important metallurgical characteristics of 18/8 stainless steel (known today as SAE 304 austenitic stainless steel) and developed a spot welding process to take advantage of the oxidized layer on the surface of stainless steel. Heat treating the 18-8 stainless steel leaves the metal with non-magnetic and ductile properties. Repeatedly reheating the metal to 1000–1100°C impairs the mechanical and chemical properties of the metal. The metal becomes susceptible to corrosion due to carbide precipitation, and loses fatigue resistance. The important factor in controlling the metal's properties is the dwell time at those temperatures. Using a controlled time element and recorder, a power supply with smooth current, and very brief high currents, a satisfactory spot weld may be produced.\nThe corona of the shot weld should not exist on the metal, and the equipment used produces satisfactory welds with a smaller than normal diameter. Sufficient electrode force is applied to hold the two sheets of metal together and the peak current rapidly creates a forge weld at the interface between the two sheets, producing a small nugget of weld metal, which when cooled results in a shear-resistant metal interface. Good shotwelds have twice the shear strength of a rivet of similar diameter and can be placed 50% closer together. When done properly, distortion, which is a problem in fusion welding processes, is eliminated.", "Engineering,_Manufacturing": 1.0000063181, "qwen": "Yes"}
{"id": "29564947", "revid": "1167014007", "url": "https://en.wikipedia.org/wiki?curid=29564947", "title": "Okuma Corporation", "text": " is a machine tool builder based in Ōguchi, Aichi Prefecture, Japan. It has global market share in CNC machine tools such as CNC lathes, machining centers, and turn-mill machining centers. The company also offers FA (factory automation) products and servomotors.\nIt is listed on the Tokyo Stock Exchange and is a component of the Nikkei 225 stock index.\nHistory.\nThe company was founded in 1898, as the Okuma Noodle Machine Co., to manufacture and sell noodle-making machines. Eiichi Okuma, the founder of the original company, was working on how to make udon more effectively. He was using lathe to make \"sticks\", that has an important role in cutting the udon noodle. But the lathes used in those days in Japan were of poor precision. This was one of big reasons which convinced Okuma to start making machine tools. In 1918 Eiichi established Okuma Machinery Works Ltd. and started selling the OS lathe.\nOkuma is a machine tool builder with a history of more than 100 years. Lathes were the main product category in the early days of company. The line now includes many CNC machine tools, including lathes, machining centers (mills), multitasking (turn-mill) machines, and grinding machines. Okuma's Double-Column Machining Center has a large market share in Japan.\nTechnological development.\nMost machine tool builders source their CNC controls from partners such as Fanuc, Mitsubishi Electric, Siemens, and Heidenhain. Several builders have developed their own CNC controls over the years (including Mazak, Okuma, Haas, Dalian Kede and others), but Okuma is unusual among machine tool builders for the degree to which it designs and builds all of its own hardware, software, and machine components. This is the company's \"Single Source\" philosophy.\nOkuma's CNC control is called the \"OSP\" series. It offers closed-loop positioning via its absolute position feedback system. The \"OSP\" name began as an abbreviation for \"Okuma Sampling Pathcontrol\".\nIn an industry that pushes hard for continual technological innovation, Okuma has often been an innovative leader. For example, it has been among the leaders of development for thermal compensation and collision avoidance. Thermal compensation is designing the machine elements and control to minimize the dimensional distortion that results from the heat generated by machining. This is done both by preventing heat buildup (for example, flowing coolant through machine elements formerly not cooled) and by detecting and compensating for temperature rises when they occur (for example, monitoring temperature with a sensor and using the sensor's output signal as input to the control logic). Collision avoidance is designing the machine to predict and prevent interference, for example, having the machine \"know\" the form and location of all fixturing so that it can foresee a crash and stop its own movement before crashing. Recent innovation includes technology to avoid chatter, both by predicting and preventing it and by early automatic detection and correction (via dynamic changes of speeds and feeds) when it does occur.", "Engineering,_Manufacturing": 0.9998677969, "qwen": "Yes"}
{"id": "29565309", "revid": "19921271", "url": "https://en.wikipedia.org/wiki?curid=29565309", "title": "Toyo Seikan", "text": " (formerly known as Toyo Seikan Kaisha, Ltd.) is a Japan-based packaging container manufacturing company.\nIt became a holding company in 2013, taking the name Toyo Seikan Group Holdings Ltd. As of March 2013, the company has 78 subsidiary and nine affiliate companies. It is listed on the first section of the Tokyo Stock Exchange and the Osaka Securities Exchange and was a constituent of the Nikkei 225 stock index.\nBusiness segments and products.\nThe Group also engages in the manufacturing and sales of hard alloys, raw material products for agriculture, sales of petroleum products, non-life insurance agency business and real estate management.", "Engineering,_Manufacturing": 0.9987767935, "qwen": "Yes"}
{"id": "29565427", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=29565427", "title": "Meidensha", "text": " is a Japanese, Tokyo-based company, engaged in the manufacturing and selling of water treatment equipment, electronic equipment, and information equipment. It is listed on the Tokyo Stock Exchange and is a constituent of the Nikkei 225.\nThe company was established by Hosui Shigemune for the manufacture of electric motors in Kyobashi, Tokyo.\nBusiness segments and products.\nThe company operates in four business segments:", "Engineering,_Manufacturing": 0.9999980927, "qwen": "Yes"}
{"id": "29566154", "revid": "23790359", "url": "https://en.wikipedia.org/wiki?curid=29566154", "title": "Feeder line (manufacturing)", "text": "A feeder line is a secondary assembly line which provides parts for use in a primary assembly line. Researchers assert that the traditional level scheduling methodology of assembly line planning is not effective unless feeder lines provide parts to the primary assembly line.", "Engineering,_Manufacturing": 0.9999865294, "qwen": "Yes"}
{"id": "19029406", "revid": "7088832", "url": "https://en.wikipedia.org/wiki?curid=19029406", "title": "Process-centered design", "text": "Process-centered design (PCD) is a design methodology, which proposes a business centric approach for designing user interfaces. Because of the multi-stage business analysis steps involved right from the beginning of the PCD life cycle, it is believed to achieve the highest levels of business-IT alignment that is possible through UI.\nPurpose.\nThis method is aimed at enterprise applications where there is a business process involved. Unlike content oriented systems such as websites or portals, enterprise applications are built to enable a company's business processes. Enterprise applications often have a clear business goal and a set of specific objectives like- improve employee productivity, increase business performance by a certain percent, etc.\nComparison between other popular UI design methods.\nAlthough there are proven UI design methodologies (like the most popular \"user-centered design\", which helps design highly Usable Interfaces), PCD differentiates itself by precisely catering to business process intensive software which has not been the case with other UI design methodologies.\nProcess-UI alignment.\nProcess-UI alignment is a component of PCD, which ensures tight alignment between the business process and the enterprise application being developed. UI design activities are affected by PCD. \nFor example: A call center software used by a customer support agent, if designed for high process-UI alignment will achieve tremendous agent productivity improvement and call center performance; which is not likely to be seen if it were designed only for user satisfaction, ease of use, etc.", "Engineering,_Manufacturing": 0.9626065493, "qwen": "Yes"}
{"id": "15604614", "revid": "10044298", "url": "https://en.wikipedia.org/wiki?curid=15604614", "title": "Built up edge", "text": "In machining, specifically cutting operations, a built-up edge (BUE) is an accumulation of material against the rake face that seizes to the tool tip, separating it from the chip.\nFormation.\nBecause shear is strongest at the initial contact surface with the cutting tool, the first layer of metal impacting and seizing on it work-hardens more than the rest of the volume of metal. As a consequence of this work hardening, this first layer of metal is stronger than the adjacent metal moving away from the workpiece. Effectively, said first layer becomes part of the tool. The process repeats itself and, after some time, a built up edge (which could be several hundred micrometres thick) forms.\nThe conditions necessary for a noticeable edge to build up are that:\nEffects on the cutting process.\nThe built up edge effectively changes tool geometry and rake steepness. It also reduces the contact area between the chip and the cutting tool, leading to:\nHowever, the formation of BUEs have negative effects on the quality of the workpiece, specifically:", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "15616001", "revid": "1127117772", "url": "https://en.wikipedia.org/wiki?curid=15616001", "title": "Book trimming", "text": "Book trimming is the stage of the book production process in which the page edges of a book are trimmed so that all pages will stack with perfect edge alignment within the finished book jacket.\nThe step before book trimming is the binding of the folded printing sheets. Trimming is performed either with a hydraulic book trimmer that is able to cut a whole book in one or two passes or, until the invention of hydraulic book trimmers, with a cutting press (or lying press) and plough.\nCutting principles.\nKnife cut principle.\nThe book-cutting machine works with three knives and uses the knife-cut principle. The knife-cut principle operates with only one knife per edge which cuts against a rubber surface. This surface supports the cut force. The three-knife-trim is performed in one step. The block is aligned and fixed by the pressure bar. The three knives cut all edges except the spine; new machines need only one step.\nShear cut principle.\nThe shear cut principle works with two knives – upper and bottom knife. The bottom knife is fixed and the upper knife works against the fixed one. Example of the shear cut principle is the cut of the paper web in the web offset machine and this is realized by a circular blade. To cut simple brochures (booklets) is used by a trimmer which works in two steps.\nBurst cut.\nThe third principle is the burst cut. This knife does not need a counter-acting tool. The required cut force is generated by the clamping force of the clamped paper. ", "Engineering,_Manufacturing": 0.9997541308, "qwen": "Yes"}
{"id": "15622906", "revid": "736651", "url": "https://en.wikipedia.org/wiki?curid=15622906", "title": "DAR 4", "text": "The DAR 4 was a prototype airliner built in Bulgaria in 1930.\nDesign and development.\nThe DAR 4 was a conventional biplane design, with unstaggered wings of unequal span braced with Warren trusses. The fuselage offered fully enclosed accommodation for the two pilots and four passengers. A curious feature of the design was that the top wing was not attached directly to the top of the fuselage as is common in cabin biplanes, but was mounted above it with cabane struts. Power was provided by three radial engines; one in the nose, and one mounted on each lower wing where the struts met. Performance was disappointing, and in particular, the narrow track of the undercarriage created difficulties. After the single prototype, no further examples were built.", "Engineering,_Manufacturing": 0.9999735355, "qwen": "Yes"}
{"id": "15628222", "revid": "43392054", "url": "https://en.wikipedia.org/wiki?curid=15628222", "title": "Form, fit and function", "text": "Form, Fit, and Function (F3) is the identification and description of characteristics of a part or assembly. Each defines a specific aspect of the part to help engineers match parts to needs. The F3 framework increases design change flexibility by allowing changes to the part with minimal documentation and design cost as long as the fit, form and function of the product are maintained. It is a step in creating any physical product.\nDefinitions.\nFit refers to the ability of the part or feature to connect to, mate with, or join to another feature or part within an assembly. The “fit” allows the part to meet the required assembly tolerances to be useful.\nForm refers to such characteristics as external dimensions, weight, size, and visual appearance of a part or assembly. This is the element of F3 that is most affected by an engineer's aesthetic choices, including enclosure, chassis, and control panel, that become the outward \"face\" of the product.\nFunction is a criterion that is met when the part performs its stated purpose effectively and reliably. In an electronics product, for example, function can depend on the solid-state components used, the software or firmware, and quite often on the features of the electronics enclosure selected. Poorly placed or sized ports and misleading or missing labeling are two of the most common ways in which an enclosure can fail the function criterion.", "Engineering,_Manufacturing": 1.0000066757, "qwen": "Yes"}
{"id": "58490571", "revid": "1159139191", "url": "https://en.wikipedia.org/wiki?curid=58490571", "title": "Slicer (3D printing)", "text": "A slicer is toolpath generation software used in the majority of 3D printing processes for the conversion of a 3D object model to specific instructions for the printer. In particular, the conversion from a model in STL format to printer commands in g-code format in fused filament fabrication and other similar processes.\nThe slicer first divides the object as a stack of flat layers, followed by describing these layers as linear movements of the 3D printer extruder, fixation laser or equivalent. All these movements, together with some specific printer commands like the ones to control the extruder temperature or bed temperature, are finally written in the g-code file, that can afterwards be transferred to the printer.\nAdditional features of the slicer.\nNearly all slicers have some additional features, like:\nList of slicer software.\nThere's a wide collection of slicer applications, some of them free and open-source. Some of the most used ones are:", "Engineering,_Manufacturing": 0.9995162487, "qwen": "Yes"}
{"id": "58504805", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=58504805", "title": "Swarm 3D printing", "text": "Swarm 3D printing or cooperative 3D printing or swarm manufacturing is a digital manufacturing platform that employs a swarm of mobile robots with different functionalities to work together to print and assemble products based on digital designs. A digital design is first divided into smaller chunks and components based on its geometry and functions, which are then assigned to different specialized robots for printing and assembly in parallel and in sequence based on the dependency of the tasks. The robots typically move freely on an open factory floor, or through the air, and could carry different tool heads. Some common tool heads include material deposition tool heads (e.g., filament extruder, inkjet printhead), pick and place tool head for embedding of pre-manufactured components, laser cutter, welding tool, etc. In some cases, operations are managed by artificial intelligence algorithms, increasingly prevalent with larger swarms or more complex robots, which require elements of autonomy to work together effectively. While in its early stage of development, swarm 3D printing is currently being commercialized by startup companies. According to Additive Manufacturing Magazine, AMBOTS is credited with creating the first end-to-end solution for cooperative 3D printing. Using the Rapid Induction Printing metal additive manufacturing process, Rosotics was the first company to demonstrate swarm 3D printing using a metallic payload, and the only to achieve metallic 3D printing from an airborne platform.", "Engineering,_Manufacturing": 0.9994493127, "qwen": "Yes"}
{"id": "62228033", "revid": "11025703", "url": "https://en.wikipedia.org/wiki?curid=62228033", "title": "Undercut (molding)", "text": "In molding, an undercut is an indentation or protrusion in a shape that will prevent its withdrawal from a one-piece mold.\nUndercuts on molded parts are features that prevent the part from being directly ejected from an injection molding machine. They are categorized into \"internal\" and \"external\" undercuts, where external undercuts are on the exterior of the part and interior undercuts are on the inside of the part. Undercuts can still be molded, but require a \"side action\" or \"side pull\". This is an extra part of the mold that moves separately from the two halves. These can increase the cost of the molded part due to an added 15 to 30% cost of the mold itself and added complexity of the molding machine.\nIf the size of the undercut is small enough and the material is flexible enough a side action is not always required. In these cases the undercut is stripped or snapped out of the mold. When this is done usually a stripping plate or ring is used instead of ejector pins so that the part is not damaged. This technique can be used on internal and external undercuts.", "Engineering,_Manufacturing": 1.0000004768, "qwen": "Yes"}
{"id": "22488730", "revid": "22301115", "url": "https://en.wikipedia.org/wiki?curid=22488730", "title": "Forming limit diagram", "text": "A forming limit diagram, also known as a forming limit curve, is used in sheet metal forming for predicting forming behavior of sheet metal. The diagram attempts to provide a graphical description of material failure tests, such as a punched dome test. \nIn order to determine whether a given region has failed, a mechanical test is performed. The mechanical test is performed by placing a circular mark on the work piece prior to deformation, and then measuring the post-deformation ellipse that is generated from the action on this circle. By repeating the mechanical test to generate a range of stress states, the formability limit diagram can be generated as a line at which failure is onset (see also formability).\nDescription.\nThe semi-axes of the ellipse formed in this circle allow for the measurement of relative strain in two primary directions, known as the major and minor directions, which correspond to the major and minor semi-axes of the ellipse. Under the assumption of path independent strain, the relative strains will reach a critical value at which deformations occur. Through repeated measurements, the shape of the curve can be obtained experimentally. Alternately, a formability limit diagram can be generated by mapping the shape of a failure criterion into the formability limit domain.\nHow ever the diagram is obtained, the resultant diagram provides a tool for the determination as to whether a given cold forming process will result in failure or not. Such information is critical in the design of forming processes, and is therefore fundamental to the design of sheet metal forming processes. Through the establishment of forming limit diagrams for a range of alloys, the forming process and alloy behavior can be matched at the metalworking design time by the process engineer.\nModern determination.\nWith the availability and use of optical strain measurement system in combination with digital data processing forming limit curves can be acquired in a more automatic and productive way compared to the classic way as described above. This procedure has been standardized and is contained in an ISO document (12004). \nIn order to obtain a full forming limit curve, test pieces with different geometries are drawn by a punch (e. g. with a diameter of 100 mm) until fracture occurs. Friction is almost zero by using a complex tribo-system with foils and grease between sheet and tool. By use of an optical strain measurement system spatial strain paths are\nevaluated immediately before failure of the test piece. Using an interpolation method for the strain variation between the severely deformed and necked area – the limits of this area are computed by a sign change of the second derivative of the strain distribution – the major and minor strain values are obtained. Using an averaged value for several cross-section evaluations and 3 test samples for the same geometry a strain pair (one point in the forming limit diagram) as forming limit is identified.\nIt is recognized by some authors that the nature of fracture and formability is intrinsically non-deterministic, since large variations might be observed even within a single experimental campaign. Therefore, the concepts of Forming Limit Bands and Forming Limit Maps have been introduced.\nInfluence parameters.\nForming limit curves (FLC) for four steel sheet grades are displayed in the attached figure. All forming limit curves have essentially the same shape. A minimum of the curve exists at the intercept with the major strain axis or close thereby, the plane strain forming limit. With the definition of the onset of local necking (e. g. membrane force reaches an extreme value) and the assumption of a hardening law according to Hollomon (σ = K εn) it can be shown that the corresponding theoretical plane strain forming limit is identical with the strain hardening coefficient, n. There is no thickness effect. Taking into account the strain rate sensitivity of the material, which is obvious in steel, along with the sheet thickness, the fact can be explained that practical forming limits, obtained by the use of the above described method, lie well above theoretical forming limits. Thus the basic influence parameters for the forming limits are, the strain hardening exponent, n, the initial sheet thickness, t0 and the strain rate hardening coefficient, m. The lankford coefficient, r, which defines the plastic anisotropy of the material, has two effects on the forming limit curve. On the left side there is no influence except that the curve extends to larger values, on the right hand side increasing r values reduce the forming limits.\nM-K method.\nThere is a widely used method for computation of FLCs, introduced by Marciniak in 1967. It assumes an inclined band in the investigated plane sheet piece with smaller thickness which denotes an imperfection. With this model limit strains can be calculated numerically. The advantage of this method is that any material model can be used and limits can also be obtained for nonproportional forming. However there is one drawback. Calculated forming limits are sensitive to the imperfection value. With the assumption of a strain rate sensitive material model realistic forming limits may be obtained which lie above theoretical limit strains. Basically with this calculation method smooth forming limit curves are generated for materials for which only one experimental value exists. A good overview of state of the art about FLC calculation methods is given in the proceedings of a conference held in Zurich in 2006 and the Numisheet conference in 2008.\nUse of FLCs.\nFor many years forming limit curves have been used in order to assess the sheet material formability. They have been applied in the design stage of tools using the finite element method as a simulation tool which is widely used in a production environment.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "22508443", "revid": "1149825650", "url": "https://en.wikipedia.org/wiki?curid=22508443", "title": "SECS/GEM", "text": "The SECS/GEM is the semiconductor's equipment interface protocol for equipment-to-host data communications. In an automated fab, the interface can start and stop equipment processing, collect measurement data, change variables and select recipes for products. The SECS (SEMI Equipment Communications Standard)/GEM (Generic Equipment Model) standards do all this in a defined way.\nDeveloped by the SEMI (Semiconductor Equipment and Materials International) organization, the standards define a common set of equipment behaviour and communications capabilities.\nThe Generic Model for Communications and Control Of Manufacturing Equipment (GEM) standard is maintained and published by the non-profit organization Semiconductor Equipment and Materials International (SEMI). Generally speaking, the SECS/GEM standard defines messages, state machines and scenarios to enable factory software to control and monitor manufacturing equipment. The GEM standard is formally designated and referred to as SEMI standard E30, but frequently simply referred to as the GEM or SECS/GEM standard. GEM intends \"to produce economic benefits for both device manufacturers and equipment suppliers...\" by defining \"... a common set of equipment behavior and communications capabilities that provide the functionality and flexibility to support the manufacturing automation programs of semiconductor device manufacturers\" [SEMI E30, 1.3]. GEM is a standard implementation of the SECS-II standard, SEMI standard E5. Many equipment in semiconductor (front end and back end), surface mount technology, electronics assembly, photovoltaic, flat panel display and other manufacturing industries worldwide provide a SECS/GEM interface on the manufacturing equipment so that the factory host software can communicate with the machine for monitoring and/or controlling purposes. Because the GEM standard was written with very few semiconductor-specific features, it can be applied to virtually any automated manufacturing equipment in any industry.\nAll GEM compliant manufacturing equipment share a consistent interface and certain consistent behavior. GEM equipment can communicate with a GEM capable host using either TCP/IP (using the HSMS standard, SEMI E37) or RS-232 based protocol (using the SECS-I standard, SEMI E4). Often both protocols are supported. Each equipment can be monitored and controlled using a common set of SECS-II messages specified by GEM.\nThere are many additional SEMI standards and factory specifications that reference the GEM standard its features. These additional standards are either industry-specific or equipment-type specific. Following are a few examples.", "Engineering,_Manufacturing": 1.0000036955, "qwen": "Yes"}
{"id": "12921851", "revid": "5718152", "url": "https://en.wikipedia.org/wiki?curid=12921851", "title": "Edison Manufacturing Company", "text": "The Edison Manufacturing Company, originally registered as the United Edison Manufacturing Company and often known as simply the Edison Company, was organized by inventor and entrepreneur Thomas Edison and incorporated in New York City in May 1889. It succeeded the Edison United Manufacturing Company, founded in 1886 as a sales agency for the Edison Lamp Company, Edison Machine Works, and Bergmann & Company, which made electric lighting fixtures, sockets, and other accessories. In April 1894, the Edison laboratory's Kinetoscope operation, which was about to be commercialized, was brought under the Edison Company umbrella. In 1900, the United Edison Manufacturing Company was evidently succeeded by the New Jersey–incorporated Edison Manufacturing Company. The company's assets and operations were transferred to Thomas A. Edison, Inc. in 1911.\nHistory.\nThe Edison United Manufacturing Company was incorporated in July 1886 to consolidate the sales operations of the various Edison manufacturing concerns. The company went into liquidation—finalized October 31, 1889—and was succeeded by the United Edison Manufacturing Company, incorporated in New York City under New York State law in May 1889. On May 4, 1900, the Edison Manufacturing Company—evidently the successor to the United Edison Manufacturing Company—was incorporated in Newark, New Jersey, with its headquarters located in West Orange.\nFrom April 1894 to June 1908, William E. Gilmore was vice-president and general manager of the Edison Manufacturing Company. He took over from Alfred O. Tate and was succeeded by patent lawyer Frank Dyer. Edison's films were made by the Kinetograph Department of the Edison Manufacturing Company.\nEdison's first moviemaking studio—and the world's first—was the Black Maria in West Orange, New Jersey, where production of Kinetoscope films began in early 1893. The Edison Studios productions moved to a Manhattan facility after the turn of the century, and a few years later to a studio in the Bronx. Filming locations around the United States and abroad were used.\nThe company had the same senior executives as the more profitable National Phonograph Company, to which Edison paid more attention. Edison was also distracted by other enterprises including storage batteries, iron ore and cement, which competed for finance and led to loss of focus.\nIn February 1911 the company's assets were assigned to Thomas A. Edison, Inc. The Edison Manufacturing Company was formally dissolved on 9 November 1926.", "Engineering,_Manufacturing": 0.9999911785, "qwen": "Yes"}
{"id": "17792824", "revid": "4921934", "url": "https://en.wikipedia.org/wiki?curid=17792824", "title": "Heading (metalworking)", "text": "Heading is a metalworking process which incorporates the forging, extruding and upsetting process. It is often performed in the cold state, resulting in cold working. This process typically produces a near net shape workpiece, which means the final product is almost finished although it can sometimes create the final product less plating or heat treating.\nAn important consideration in heading is the tendency for the wire to buckle if its unsupported length to diameter ratio is too high. This ratio usually is limited to less than 3:1 but with appropriate dies, it can be higher.\nThere are a variety of cold heading machines but typically for fastener manufacturing you will see one die two blow up to five die six blow and beyond. Multi-die headers allow for more complex parts to be formed as part of one process due to the above limitations of diameter ratio reductions.\nSome advantages of cold heading a part over using a CNC lathe or Swiss screw machine include reduced part cost both through production speed (60-400 parts per minute) and the minimal scrap generated from a cold headed part. Also, because the part is formed rather than cut, the grain flow stays intact and creates a much stronger part for its size. ", "Engineering,_Manufacturing": 0.9999476671, "qwen": "Yes"}
{"id": "17801764", "revid": "10248457", "url": "https://en.wikipedia.org/wiki?curid=17801764", "title": "Hot working", "text": "In metallurgy, hot working refers to processes where metals are plastically deformed above their recrystallization temperature. Being above the recrystallization temperature allows the material to recrystallize during deformation. This is important because recrystallization keeps the materials from strain hardening, which ultimately keeps the yield strength and hardness low and ductility high. This contrasts with cold working.\nMany kinds of working, including rolling, forging, extrusion, and drawing, can be done with hot metal.\nTemperature.\nThe lower limit of the hot working temperature is determined by its recrystallization temperature. As a guideline, the lower limit of the hot working temperature of a material is 60% its melting temperature (on an absolute temperature scale). The upper limit for hot working is determined by various factors, such as: excessive oxidation, grain growth, or an undesirable phase transformation. In practice materials are usually heated to the upper limit first to keep forming forces as low as possible and to maximize the amount of time available to hot work the workpiece.\nThe most important aspect of any hot working process is controlling the temperature of the workpiece. 90% of the energy imparted into the workpiece is converted into heat. Therefore, if the deformation process is quick enough the temperature of the workpiece should rise, however, this does not usually happen in practice. Most of the heat is lost through the surface of the workpiece into the cooler tooling. This causes temperature gradients in the workpiece, usually due to non-uniform cross-sections where the thinner sections are cooler than the thicker sections. Ultimately, this can lead to cracking in the cooler, less ductile surfaces. One way to minimize the problem is to heat the tooling. The hotter the tooling the less heat lost to it, but as the tooling temperature rises, the tool life decreases. Therefore the tooling temperature must be compromised; commonly, hot working tooling is heated to 500–850 °F (325–450 °C).\nAdvantages and disadvantages.\nThe advantages are:\nUsually the initial workpiece that is hot worked was originally cast. The microstructure of cast items does not optimize the engineering properties, from a microstructure standpoint. Hot working improves the engineering properties of the workpiece because it replaces the microstructure with one that has fine spherical shaped grains. These grains increase the strength, ductility, and toughness of the material.\nThe engineering properties can also be improved by reorienting the inclusions (impurities). In the cast state the inclusions are randomly oriented, which, when intersecting the surface, can be a propagation point for cracks. When the material is hot worked the inclusions tend to flow with the contour of the surface, creating \"stringers\". As a whole the strings create a \"flow structure\", where the properties are anisotropic (different based on direction). With the stringers oriented parallel to the surface it strengthens the workpiece, especially with respect to fracturing. The stringers act as \"crack-arrestors\" because the crack will want to propagate through the stringer and not along it.\nThe disadvantages are:", "Engineering,_Manufacturing": 0.9999938011, "qwen": "Yes"}
{"id": "186164", "revid": "42425010", "url": "https://en.wikipedia.org/wiki?curid=186164", "title": "Logistics engineering", "text": "Logistics engineering is a field of engineering dedicated to the scientific organization of the purchase, transport, storage, distribution, and warehousing of materials and finished goods. Logistics engineering is a complex science that considers trade-offs in component/system design, repair capability, training, spares inventory, demand history, storage and distribution points, transportation methods, etc., to ensure the \"thing\" is where it's needed, when it's needed, and operating the way it's needed all at an acceptable cost.\nOverview.\nLogistics is generally concerned with cost centre service activities, but provides value via improved efficiency and customer satisfaction. It can quickly lose that value if the customer becomes dissatisfied. The end customer can include another process or work center inside of the manufacturing facility, a warehouse where items are stocked or the final customer who will use the product. Another approach which has appeared in recent years is the supply chain management. The supply chain also looks at an efficient chaining of the supply / purchase and distribution sides of an organization. While logistics looks at single echelons with the immediate supply and distribution linked up, supply chain looks at multiple echelons/stages, right from procurement of the raw materials to the final distribution of finished goods up to the customer. It is based on the basic premise that the supply and distribution activities if integrated with the manufacturing / logistic activities, can result in better profitability for the organization. The local minimum of total cost of the manufacturing operation is getting replaced by the global minimum of total cost of the whole chain, resulting in better profitability for the chain members and hence lower costs for the products.\nLogistics engineering as a discipline is a very important aspect of systems engineering that also includes reliability engineering. It is the science and process whereby reliability, maintainability, and availability are designed into products or systems. It includes the supply and physical distribution considerations above as well as more fundamental engineering considerations. Logistics engineers work with complex mathematical models that consider elements such as mean time between failures (MTBF), mean time to failure (MTTF), mean time to repair (MTTR), failure mode and effects analysis (FMEA), statistical distributions, queueing theory, and a host of other considerations. For example, if we want to produce a system that is 95% reliable (or improve a system to achieve 95% reliability), a logistics engineer understands that total system reliability can be no greater than the least reliable subsystem or component. Therefore, our logistics engineer must consider the reliability of all subcomponents or subsystems and modify system design accordingly. If a subsystem is only 50% reliable, one can concentrate on improving the reliability of that subsystem, design in multiple subsystems in parallel (5 in this case would achieve approximately 97% reliability of that subsystem), purchase and store spare subsystems for rapid change out, establish repair capability that would get a failed subsystem back in operation in the required amount of time, and/or choose any combination of those approaches to achieve the optimal cost vs. reliability solution. Then the engineer moves onto the next subsystem.\nTerminology.\nThere are few differences between the terms business logistics and logistics engineering. Logistics engineering is more focused on the mathematical or scientific application of logistics.\nFields and topics.\nThe various fields and topics that logistics engineers are involved with include:\nPerformance metrics.\nDifferent performance metrics (measures of performance) are used to examine the efficiency of an organization's logistics. The most popular and widely used performance metric is the landed cost. The landed cost is the total cost of purchasing, transporting, warehousing and distributing raw materials, semi-finished and finished goods.\nAnother performance metric equally important is the end customer fill rate. It is the percentage of customer demand which is satisfied immediately off-the-shelf (from on-site inventory). An alternative to fill rate, is system availability.\nIn recent years, the United States Department of Defense (DoD) has advocated the use of performance-based logistics (PBL) contracts to manage costs for support of weapon systems.\nEducation.\nMany top universities offer Logistics engineering programs at undergraduate and graduate levels. These programs generally combine strategy, operations, facility design, technology and management. The following institutions provide Logistics engineering programs around the world:", "Engineering,_Manufacturing": 0.9678450823, "qwen": "Yes"}
{"id": "186493", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=186493", "title": "Supply chain", "text": "A supply chain, sometimes expressed as a \"supply-chain\", is a complex logistics system that consists of facilities that convert raw materials into finished products and distribute them to end consumers or end customers. Meanwhile, supply chain management deals with the flow of goods within the supply chain in the most efficient manner.\nIn sophisticated supply chain systems, used products may re-enter the supply chain at any point where residual value is recyclable. Supply chains link value chains. Suppliers in a supply chain are often ranked by \"tier\", with first-tier suppliers supplying directly to the client, second-tier suppliers supplying to the first tier, and so on.\nOverview.\nA typical supply chain can be divided into two stages namely, production and distribution stages. In the production stage, components and semi-finished parts are produced in manufacturing centres. The components are then put together in an assembly plant. The distribution stage consists of central and regional distribution centres that transport products to end-consumers.\nAt the end of the supply chain, materials and finished products only flow there because of the customer behaviour at the end of the chain; academics Alan Harrison and Janet Godsell argue that \"supply chain processes should be co-ordinated in order to focus on end customer buying behaviour\", and look for \"customer responsiveness\" as an indicator confirming that materials are able to flow \"through a sequence of supply chain processes in order to meet end customer buying behaviour\".\nMany of the exchanges encountered in the supply chain take place between varied companies that seek to maximize their revenue within their sphere of interest but may have little or no knowledge or interest in the remaining players in the supply chain. More recently, the loosely coupled, self-organizing network of businesses who cooperate in providing product and service offerings has been called the \"extended enterprise\", and the use of the term \"chain\" and the linear structure it appears to represent have been criticised as \"harder to relate ... to the way supply networks really operate. A chain is actually a complex and dynamic supply and demand network.\nAs part of their efforts to demonstrate ethical practices, many large companies and global brands are integrating codes of conduct and guidelines into their corporate cultures and management systems. Through these, corporations are making demands on their suppliers (facilities, farms, subcontracted services such as cleaning, canteen, security etc.) and verifying, through social audits, that they are complying with the required standard. A lack of transparency in the supply chain can bar consumers from knowledge of where their purchases originated and facilitate socially irresponsible practices. In 2018, the Loyola University Chicago's Supply and Value Chain Center found in a survey that 53% of supply chain professionals considered ethics to be \"extremely\" important to their organization.\nTypologies.\nMarshall L. Fisher (1977) asks the question in a key article, \"Which is the right supply chain for your product?\" Fisher, and also Naylor, Naim and Berry (1999), identify two matching characteristics of supply chain strategy: a combination of \"functional\" and \"efficient\", or a combination of \"responsive\" and \"innovative\" (Harrison and Godsell).\nBrown \"et al.\" refer to supply chains as either \"loosely coupled\" or \"tightly coupled\": These ideas refer to two polar models of collaboration: tightly coupled, or \"hard-wired\", also known as \"linked\", collaboration represents a close relationship between a buyer and supplier within the chain, whereas a loosely-coupled link relates to low interdependency between buyer and seller and therefore greater flexibility. The Chartered Institute of Procurement & Supply's professional guidance suggests that the aim of a tightly coupled relationship is to reduce inventory and avoid stock-outs.\nModeling.\n There are a variety of supply-chain models, which address both the upstream and downstream elements of supply-chain management (SCM). The SCOR (Supply-Chain Operations Reference) model, developed by a consortium of industry and the non-profit Supply Chain Council (now part of APICS) became the cross-industry \"de facto\" standard defining the scope of supply-chain management. SCOR measures total supply-chain performance. It is a process reference model for supply-chain management, extending \"from the supplier's supplier to the customer's customer\". It includes delivery and order fulfillment performance, production flexibility, warranty and returns processing costs, inventory and asset turns, and other factors in evaluating the overall effective performance of a supply chain.\nA supply chain can often be split into different segments: the earlier stages of a supply chain, such as raw material processing and manufacturing, determine their break-even point by considering production costs relative to market price. The later stages of a supply chain, such as wholesale and retail determine their break-even point by considering transaction costs, relative to market price. Additionally, there are financial costs associated with all the stages of a supply chain model.\nThe Global Supply Chain Forum has introduced an alternative supply chain model. This framework is built on eight key business processes that are both cross-functional and cross-firm in nature. Each process is managed by a cross-functional team including representatives from logistics, production, purchasing, finance, marketing, and research and development. While each process interfaces with key customers and suppliers, the processes of customer relationship management and supplier relationship management form the critical linkages in the supply chain.\nThe American Productivity and Quality Center (APQC) Process Classification Framework (PCF) SM is a high-level, industry-neutral enterprise process model that allows organizations to see their business processes from a cross-industry viewpoint. The PCF was developed by APQC and its member organizations as an open standard to facilitate improvement through process management and benchmarking, regardless of industry, size, or geography. The PCF organizes operating and management processes into 12 enterprise-level categories, including process groups, and over 1,000 processes and associated activities.\nIn the developing country public health setting, John Snow, Inc. has developed the JSI Framework for Integrated Supply Chain Management in Public Health, which draws from commercial sector best practices to solve problems in public health supply chains.\nMapping.\nSimilarly, supply chain mapping involves documenting information regarding all participants in an organisation's supply chain and assembling the information as a global map of the organisation's supply network.\nManagement.\nIn the 1980s, the term supply-chain management (SCM) was developed to express the need to integrate the key business processes, from end user through original suppliers. Original suppliers are those that provide products, services, and information that add value for customers and other stakeholders. The basic idea behind SCM is that companies and corporations involve themselves in a supply chain by exchanging information about market demand, distribution capacity and production capabilities. Keith Oliver, a consultant at Booz Allen Hamilton, is credited with the term's invention after using it in an interview for the \"Financial Times\" in 1982. The term was used earlier by Alizamir et al. in 1981, and Burns and Sivazlian in 1978.\nIf all relevant information is accessible to any relevant company, every company in the supply chain has the ability to help optimize the entire supply chain rather than to sub-optimize based on local optimization. This will lead to better-planned overall production and distribution, which can cut costs and give a more attractive final product, leading to better sales and better overall results for the companies involved. This is one form of vertical integration. Yet, it has been shown that the motives for and performance efficacy of vertical integration differ by global region.\nIncorporating SCM successfully leads to a new kind of competition on the global market, where competition is no longer of the company-versus-company form but rather takes on a supply-chain-versus-supply-chain form.\nThe primary objective of SCM is to fulfill customer demands through the most efficient use of resources, including distribution capacity, inventory, and labor. In theory, a supply chain seeks to match demand with supply and do so with minimal inventory. Various aspects of optimizing the supply chain include liaising with suppliers to eliminate bottlenecks; sourcing strategically to strike a balance between lowest material cost and transportation, implementing just-in-time techniques to optimize manufacturing flow; maintaining the right mix and location of factories and warehouses to serve customer markets; and using location allocation, vehicle routing analysis, dynamic programming, and traditional logistics optimization to maximize the efficiency of distribution.\nThe term \"logistics\" applies to activities within one company or organization involving product distribution, whereas \"supply chain\" additionally encompasses manufacturing and procurement, and therefore has a much broader focus as it involves multiple enterprises (including suppliers, manufacturers, and retailers) working together to meet a customer need for a product or service.\nStarting in the 1990s, several companies chose to outsource the logistics aspect of supply-chain management by partnering with a third-party logistics provider (3PL). Companies also outsource production to contract manufacturers. Technology companies have risen to meet the demand to help manage these complex systems. Cloud-based SCM technologies are at the forefront of next-generation supply chains due to their impact on optimization of time, resources, and inventory visibility. Cloud technologies facilitate work being processed offline from a mobile app which solves the common issue of inventory residing in areas with no online coverage or connectivity.\nPerformance.\nSupply chain managers are under constant scrutiny to secure the best pricing for their resources, which becomes a difficult task when faced with the inherent lack of transparency. Cost benchmarking helps to identify competitive pricing within the industry but benchmarking across a range of supply chain performance factors has been recommended as best practice. The SCOR model contains more than 150 key indicators which measure the performance of supply chain operations: see also Supply chain operations reference#Performance measurements. Debra Hofman has noted that \"measuring supply chain performance is not a new practice. Most companies today measure at least some aspect of their supply chain and understand the need for a more comprehensive measurement program.\" However, the abundance of options for potential performance metrics to use is seen as a challenge for supply chain managers. One approach is to relate multiple measures in a hierarchical structure so that interdependencies and the contribution of multiple indicators to the \"key\" or most significant imetrics can be more easily seen. Hofman suggests that the three key indicators of a well-functioning supply chain are:\nA Cranfield University boardroom survey in 2010 found evidence that many organisations recognised the importance of the supply chain contribution to their business success, with a focus on cost, customer lead-time and customer quality being the primary performance indicators.\nResilience.\nSupply chain resilience is \"the capacity of a supply chain to persist, adapt, or transform in the face of change\". For a long time, the interpretation of resilience in the sense of engineering resilience (or robustness) prevailed in supply chain management, leading to the notion of \"persistence\". A popular implementation of this idea is given by measuring the \"time-to-survive\" and the \"time-to-recover\" of the supply chain, allowing identification of weak points in the system. More recently, the interpretations of resilience in the sense of ecological resilience and social–ecological resilience have led to the notions of \"adaptation\" and \"transformation\", respectively. A supply chain is thus interpreted as a social-ecological system which – similar to an ecosystem (e.g. forest) – is able to constantly adapt to external environmental conditions and – through the presence of social actors and their ability to foresight – also to transform itself into a fundamentally new system. This leads to a panarchical interpretation of a supply chain, embedding it into a system of systems, allowing to analyze the interactions of the supply chain with systems that operate at other levels (e.g. society, political economy, planet Earth). For example, these three components of resilience can be identified in relation to the 2021 Suez Canal obstruction, when a ship blocked the canal for several days. Persistence means to \"bounce back\"; in our example it is about removing the ship as quickly as possible to allow \"normal\" operations. Adaptation means to accept that the system has reached to a \"new normal\" state and to act accordingly; here, this can be implemented by redirecting ships around the African cape or use alternative modes of transport. Finally, transformation means to question the assumptions of globalization, outsourcing, and linear supply chains and to envision alternatives; in this example this could lead to local and circular supply chains.\nSupply chain resilience has been identified as an important business issue. The United Kingdom's Confederation of British Industry reported in 2014 that a significant number of businesses had reshored parts of their supply chain to European locations, with many identifying supply chain resilience as \"a key factor in their decision to do so\".\nSocial responsibility.\nIncidents like the 2013 Savar building collapse with more than 1,100 victims have led to widespread discussions about corporate social responsibility across global supply chains. Wieland and Handfield (2013) suggest that companies need to audit products and suppliers and that supplier auditing needs to go beyond direct relationships with first-tier suppliers (those who supply the main customer directly). They also demonstrate that visibility needs to be improved if the supply cannot be directly controlled and that smart and electronic technologies play a key role to improve visibility. Finally, they highlight that collaboration with local partners, across the industry and with universities is crucial to successfully manage social responsibility in supply chains. This incident also highlights the need to improve workers safety standards in organizations. Hoi and Lin (2012) note that corporate social responsibility can influence the enacting of policies that can improve occupational safety and health management in organizations. In fact, international organizations with presence in other nations have a responsibility to ensure that workers are well protected by policies in an organization to avoid safety related incidents.\nFood supply chains.\nMany agribusinesses and food processors source raw materials from smallholder farmers. This is particularly true in certain sectors, such as coffee, cocoa and sugar. Over the past 20 years, there has been a shift towards more traceable supply chains. Rather than purchasing crops that have passed through several layers of collectors, firms are now sourcing directly from farmers or trusted aggregators. The drivers for this change include concerns about food safety, child labor and environmental sustainability as well as a desire to increase productivity and improve crop quality.\nIn October 2009, the European Commission issued a \"Communication\" concerning \"a better functioning food supply chain in Europe\", addressing the three sectors of the European economy which comprise the food supply chain: agriculture, food processing industries, and the distribution sectors. An earlier interim report on food prices (published in December 2008) had already raised concerns about the food supply chain. Arising out of the two reports, the Commission established a \"European Food Prices Monitoring Tool\", an initiative developed by Eurostat and intended to \"increase transparency in the food supply chain\".\nIn March 2022 the Commission noted \"the need for EU agriculture and food supply chains to become more resilient and sustainable\".\nRegulation.\nSupply chain security has become particularly important in recent years. As a result, supply chains are often subject to global and local regulations. In the United States, several major regulations emerged in 2010 that have had a lasting impact on how global supply chains operate. These new regulations include the Importer Security Filing (ISF) and additional provisions of the Certified Cargo Screening Program. EU's draft supply chain law are due diligence requirements to protect human rights and the environment in the supply chain.\nTrends affecting supply chains.\nWith the increasing globalization and easier access to different kinds of alternative products in today's markets, the contribution of product design to generating demand is more significant than ever. In addition, as supply, and therefore competition, among companies for the limited market demand increases and as pricing and other marketing elements become less distinguishing factors, product design likewise plays a different role by providing attractive features to generate demand. In this context, demand generation is used to define how attractive a product design is in terms of creating demand. In other words, it is the ability of a product's design to generate demand by satisfying customer expectations. But product design affects not only demand generation but also manufacturing processes, cost, quality, and lead time. The product design affects the associated supply chain and its requirements directly, including manufacturing, transportation, quality, quantity, production schedule, material selection, production technologies, production policies, regulations, and laws. Broadly, the success of the supply chain depends on the product design and the capabilities of the supply chain, but the reverse is also true: the success of the product depends on the supply chain that produces it.\nAccording to an industrial engineering study which looked at a process for \"Design for Supply Chain\" (DFSC), since the product design imposes multiple requirements on the supply chain, then once a product design is completed, it drives the structure of the supply chain, limiting the flexibility of engineers to generate and evaluate different (and potentially more cost-effective) supply-chain alternatives. Design for Supply Chain is described as\nSupply chain consultant Anthony Tarantino has identified a number of best practices affecting the resilience and operation of supply chains, including the formation of multi-disciplinary centres of excellence, hybrid supply chain organizations which optimise the balance between centralisation and de-centralisation, and more extensive use of both structured and unstructured data.\nBig Data is increasingly being utilized in supply chain management , especially in the strategic purchasing and supply management sector. Effective application of Big Data can improve the performance of supply chain activities through improved decision-making capabilities.\nWith the increased complexity and b2b activity associated with economic growth, actors often seek to view supply chain collaboration as a part of the value adding activities in a value chain.", "Engineering,_Manufacturing": 0.9512758255, "qwen": "Yes"}
{"id": "40440798", "revid": "5839411", "url": "https://en.wikipedia.org/wiki?curid=40440798", "title": "Turned, ground, and polished", "text": "Turned, ground, and polished (TGP) is a classification of finishing processes often used for metal shafting. Turning (on a lathe) creates straight round bars without the strain induced by cold drawing, while grinding and polishing improves the surface finish and roundness for high dimensional accuracy. Extreme straightness is critical in high-speed applications to prevent vibration and reduce wear on bearings.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "49466458", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=49466458", "title": "Rapid tooling", "text": "Rapid tooling (RT) denotes manufacturing on a slim timeline. Some of the main advantages to rapid tooling trades is that it decreases the time and cost of the product. With rapid tools being fast and easily reproducible, it requires less stock for finished tools. These tools will be produced on demand and are available almost immediately. Special tools or tools where no supplier is existing on the market any more can be reproduced without bigger design and production efforts. However, the disadvantages are that it is not as accurate and also shortens the lifespan of the product.\nRapid tooling is mainly used for specific needs including prototyping and troubleshooting existing problems. Rapid prototyping is not often used for large scale and long term operations for a part. Nevertheless, rapid tooling is starting to be used to create molds for commercial operations because the time lag is so short between start to finish and since a CAD file is the only thing needed for the design stage. Since alternate methods require precious time and resources, rapid tooling provides a way to quickly provide molds for the required products. This allows companies to quickly make commercial products with the advances of rapid prototyping.\nIn addition, rapid tooling provides the customization necessary for personal applications. Instead of tedious trial and error measurements, rapid prototyping processes allow scientists and doctors the ability to scan and digitize the item or patient. Then by putting it through a CAD program, a personal custom mold can be created to fix the problem. An example of this procedure is for dental patients. Originally to fabricate an oral application, an alginate impression or a wax registration is used to fit the teeth with the mold. With new advances, doctors can take a scan of the dental arches to correctly and quickly make a mold out of silicone for the patient. This allows for better accuracy and more acute customization of the mold in the future.", "Engineering,_Manufacturing": 0.9936430454, "qwen": "Yes"}
{"id": "49474386", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=49474386", "title": "Stafa Industrier", "text": "Stafa Industrier AS, headquartered in Grimstad, Norway, is the parent company of a group of companies primarily offering manufacturing services and products from sheet-metal: Stansefabrikken Products AS, Stansefabrikken Fredrikstad AS, UAB Stansefabrikken Automotive Lithuania, UAB Stansefabrikken Lithuania and UAB Pramones Parkas Lithuania.\nHistory.\nThe Stafa Group originates from the company Den Norske Stansefabrik first established in Oslo, Norway in 1932 and transferred to Lillesand in 1947. In 1985, after Den Norske Stansefabrik went bankrupt, the current main owners took over the operations and formed \"Stansefabrikken Lillesand AS\". Since then, through acquisitions and forming of new companies, the business has grown into a company group with a parent company, Stafa Industrier AS.\nDescription.\nStafa Industrier AS operates in five main areas of business: Sheet metal subcontracting, Automotive, Products (electrical cabinets, fuse cabinets, house-centrals, shop fitting equipment and post boxes out of sheet metal), product development, renting of premises (industrial park in Ukmergė, Lithuania). Stafa Industrier AS manages of 7 subsidiaries with a total number of approximately 375 employees:", "Engineering,_Manufacturing": 0.9997729659, "qwen": "Yes"}
{"id": "6448487", "revid": "34708606", "url": "https://en.wikipedia.org/wiki?curid=6448487", "title": "Pocket-hole joinery", "text": "Pocket-hole joinery, or pocket-screw joinery, involves drilling a hole at an angle — usually 15 degrees — into one work piece, and then joining it to a second work piece with a self-tapping screw.\nPocket hole machines.\nModern pocket hole machines are capable of routing low-angle pockets - as low as 3 degrees - creating more flush, stronger joints by minimizing the joint shift or “creep” that occurs when creating pockets and joints by using a pocket hole jig or by hand. Max Durney, founder of Castle USA, invented the very first pocket hole machine and was awarded the first pocket hole machine patent. Castle USA continues to manufacturer 3 degree and 6 degree pocket hole machinery at its headquarters in Petaluma, CA. \nPocket hole jigs.\nPocket holes can be formed by drilling a series of holes until a pocket hole is created, but pocket hole jigs make the process much quicker and easier. Pocket hole jigs allow the user to drill a hole at an accurate angle to get a good joint. Using a pocket hole jig also makes for a cleaner and neater appearance as opposed to creating a pocket hole without the help of a jig. A pocket hole jig is generally made of plastic and has a metal insert that the drill bit is inserted through to drill the hole. A jig can be a stationary device that the wooden pieces are clamped into, or a portable device that is clamped onto the wooden pieces.\nTechnique.\nWhen joining boards at a right angle, it is important that the cuts are precise and square to prevent gaps or un-perpendicular joints between the boards. Some woodworkers lay out their project before drilling their pocket holes and mark the face of the board that they want to drill to ensure the hole is in the correct location. Most pocket joints are made by screwing into the face or the edge of the board rather than the end grain because the screw will grab better.\nPocket hole joint screws.\nSelf-tapping pocket screws are used for pocket hole joints. Pocket screws are generally more expensive, but they are needed for a tight, strong joint. Pocket screws have a wide washer head to spread the load for a firm bond, and prevent screwing too far into the joint and cracking the wood. The self tapping screws will grip any type of wood, but coarse threads are needed for softer wood and fine threads are needed for harder.\nPocket hole joint screws will vary in length depending on the thicknesses of the 2 pieces of material being joined. This is an important factor in correctly laying out a pocket hole joint, and a common cause for error.", "Engineering,_Manufacturing": 0.99983567, "qwen": "Yes"}
{"id": "6461531", "revid": "14703151", "url": "https://en.wikipedia.org/wiki?curid=6461531", "title": "Pultrusion", "text": "Pultrusion is a continuous process for manufacture of fibre-reinforced plastics with constant cross-section. The term is a portmanteau word, combining \"pull\" and \"extrusion\". As opposed to extrusion, which pushes the material, pultrusion pulls the material.\nA very early pultrusions type patent was filed by J.H. Watson in 1944. This was followed by M.J. Meek's filing of 1950. The first commercial pultrusions were provided by Glastic Company of Cleveland, Ohio under the patent filed in 1952 by Rodger B. White. The patent issued to W. B. Goldsworthy in 1959 helped initiate the promotion and knowledge spread within the industry. W. Brandt Goldsworthy is widely regarded as the inventor of pultrusion.\nParallel to the work of Goldsworthy, who concentrated his work on unsaturated polyester resins, Ernst Kühne in Germany developed a quite similar process in 1954 based on epoxy resin.\nInvention, development and the issuance of patents continue in the pultrusion field through today. A later innovation in this field has been developed and patented by Thomas GmbH + Co. Technik + Innovation KG in Germany 2008 and is described below.\nProcess.\nIn the standard pultrusion process the reinforcement materials like fibers or woven or braided strands are impregnated with resin, possibly followed by a separate preforming system, and pulled through a heated stationary die where the resin undergoes polymerization. The impregnation is either done by pulling the reinforcement through a bath or by injecting the resin into an injection chamber which typically is connected to the die. Many resin types may be used in pultrusion including polyester, polyurethane, vinylester and epoxy. Resin provides the resistance to the environment, (i.e., the corrosion resistance, the UV resistance, the impact resistance, etc.) and the glass provides strength, in addition to safety from fire.\nA surface veil can also be added to protect against erosion or “fiber bloom” and provide corrosion resistance and ultraviolet resistance.\nThe technology is not limited to thermosetting polymers. More recently, pultrusion has been successfully used with thermoplastic matrices such as polybutylene terephthalate (PBT), polyethylene terephthalate (PET) either by powder impregnation of the glass fiber or by surrounding it with sheet material of the thermoplastic matrix, which is then heated.\nEcological cleanness of manufactured products, in contrast to composites on thermosetting resins base, as well as practically unlimited possibilities of recycling (processing) after the resource depletion appear to be forcible arguments in favor of reinforced thermoplastics. For these reasons the industrial output and use of the given materials in highly industrialized countries have increased by 8–10% per year in recent decades. New developments (see process modifications) which enable the manufacturing not only of straight but also curved profiles are actually pushing the demand for this technology, especially in the automotive sector.\nPultrusion technology of manufacturing of fiber composites with polymer matrix appears to be energy-efficient and resource-saving.\nEconomic and environmental factors favor use of a thermoplastic matrix but due to the high viscosity of melts it is difficult to achieve high productivity and high quality of fiberfills impregnation with this type of matrix.\nProducts manufactured under this technology are widely used in the following industries:\nProcess modifications.\nAs the materials are pulled through a die in the standard pultrusion process the process is only suited to manufacture straight profiles.\nIn a recently developed modification of the process, developed and patented by Thomas GmbH + Co. Technik + Innovation KG, the die is no longer stationary but moving back and forth along the profile to be manufactured. This modified process, known as \"Radius-Pultrusion\" allows also to manufacture two- and three-dimensional curved profiles. It also is beneficiary for a number of tasks in the linear process especially if quite complex textile reinforcements with a low rate of distortion are needed.\nEquipment.\nThe design of pultrusion machines varies. Two often used types are reciprocating (hand-over-hand) and continuous (cat-track).\nFor the radius pultrusion process the layout of the machines has two moving stages similar to the hand over hand pulling unit, but as the process is intermittent with only one puller and the mould mounted on the stage of other one. Whether the stages are moving linear or circular depends on the type of profiles to be manufactured. The minimum radius for a linear machine with rotating stages is approx. 2 m. For smaller radii a circular movement of the mould and gripper stage is necessary.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "25997953", "revid": "1146564179", "url": "https://en.wikipedia.org/wiki?curid=25997953", "title": "Centrifugal casting (industrial)", "text": "Centrifugal casting or rotocasting is a casting technique that is typically used to cast thin-walled cylinders. It is typically used to cast materials such as metals, glass, and concrete. A high quality is attainable by control of metallurgy and crystal structure. Unlike most other casting techniques, centrifugal casting is chiefly used to manufacture rotationally symmetric stock materials in standard sizes for further machining, rather than shaped parts tailored to a particular end-use.\nMaterials.\nTypical materials that can be centrifugal cast are metals, cements, concretes, glass, and pottery materials. Typical metals cast are iron, steel, stainless steels, and alloys of nickel, aluminum, and copper, magnesium.\nTwo materials can be combined by introducing a second material during the process. A common example is cast iron pipe coated on the interior with cement.\nProcess for casting metal.\nIn centrifugal casting, a permanent mold is rotated continuously at high speeds (300 to 3000 rpm) as the molten metal is poured. The molten metal spreads along the inside mold wall, where it solidifies after cooling. The casting is usually a fine-grained casting with an especially fine-grained outer diameter, due to the rapid cooling at the surface of the mold. Lighter impurities and inclusions move towards the inside diameter and can be machined away following the casting.\nCasting machines may be either horizontal or vertical-axis. Horizontal axis machines are preferred for long, thin cylinders, vertical machines for rings and bearings.\nCastings usually solidify from the outside in. This directional solidification improves some metallurgical properties. Often the inner and outermost layers are removed and only the intermediary \"columnar zone\" is used.\nCentrifugal casting was the invention of Alfred Krupp, who used it to manufacture railway tyres (cast steel tyres for railway wheels) starting in 1852.\nApplications.\nTypical parts made by this process are pipes, flywheels, cylinder liners, and other parts that are axi-symmetric. It is notably used to cast cylinder liners and sleeve valves for piston engines, parts which could not be reliably manufactured otherwise.\nGlass.\nThe technique is known in the glass industry as \"spinning\". The centrifugal force pushes the molten glass against the mold wall, where it solidifies. The cooling process often takes between 16 and 72 hours depending on the impurities or volume of material. Typical products made using this process are television tubes and missile nose cones.\nSpin casting is also used to manufacture large telescope mirrors, where the natural curve followed by the molten glass greatly reduces the amount of grinding required. Rather than pouring glass into a mold an entire turntable containing the peripheral mold and the back pattern (a honeycomb pattern to reduce the mass of the finished product) is contained within a furnace and charged with the glass material used. The assembly is then heated and spun at slow speed until the glass is liquid, then gradually cooled over a period of months.\nCentrifugal casting is also commonly used to shape glass into spherical objects such as marbles.\nBenefits.\nCylinders and shapes with rotational symmetry are most commonly cast by this technique. Long castings are often produced with the long axis parallel to the ground rather than standing up in order to distribute the effect of gravity evenly. \nThin-walled cylinders are difficult to cast by other means. Centrifugal casting is particularly suited as they behave in the manner of shallow flat castings relative to the direction of the centrifugal force.\nCentrifugal casting is also used to manufacture disk and cylinder shaped objects such as railway carriage wheels or machine fittings where grain, flow, and balance are important to the durability and utility of the finished product.\nNoncircular shapes may also be cast providing the shape is relatively constant in radius.\nExternal links.\nCentrifugal Casting Ductile Iron Pipe", "Engineering,_Manufacturing": 0.9998312593, "qwen": "Yes"}
{"id": "55052303", "revid": "44982469", "url": "https://en.wikipedia.org/wiki?curid=55052303", "title": "Maslow CNC", "text": "Maslow CNC is an open-source CNC router project. It is the only commercially available vertical CNC router and is notable for its low cost of US$500. \nAlthough the kit is advertised at $500, like many tools, additional initial material and hardware costs are required. The kits are now sold by three re-sellers range in price from $400 to $500. Lumber and plywood are required to make the machine's frame along with an appropriate and compatible router. Lastly, a personal computer or tablet is needed with Windows, Mac OSX or Linux as its operating system. Overall initial material material costs approximately $800. \nThe unique vertical design mimics a hanging plotter allowing it to have a 4' x 8' cutting area with a footprint 10' wide x 19\" deep. Maslow CNC uses geared motors with encoders (8148 counts/rev) and a closed loop feedback system to achieve a resolution of ±0.4mm. To reduce cost, Maslow CNC comes in kit form, uses a commercial off-the-shelf handheld router provided by the user for the router spindle, uses an Arduino Mega microprocessor, and uses a large number of common hardware items rather than custom parts.\nThe Maslow CNC project was created 2016 by Bar Smith, Hannah Teagle and Tom Beckett. The project was funded with preorders on Kickstarter, raising $314,000. It was featured on Tested and was shown at Maker Faire Bay Area 2017. \nThe original company is no longer selling the kits.", "Engineering,_Manufacturing": 0.9999170303, "qwen": "Yes"}
{"id": "55056771", "revid": "4637213", "url": "https://en.wikipedia.org/wiki?curid=55056771", "title": "Drawer slides roll forming machine", "text": "A drawer slide roll forming machine is a cold roll forming machine used to manufacture drawer slides. They have similarities with roofing roll formed products, but require a higher performance and skills in profile forming.\nThese machines are also known under various names such as slide rail making machine, slide make machine and telescopic channel roll forming equipment. \nProcess of slide roll forming.\nThe basic production flow of drawer slide machine is roll forming, punching, and cut off to length. \nProcesses of drawer slides roll forming is a continuous cold rolled steel strip passing through a plurality set of upper and lower shaped rollers, and then punching, embossing, straightening, and cut off to length. Straightening is an important part to avoid material twisting or curling. A roll forming line is often provided with straightening mechanism to make sure the material is nicely formed in a predetermined shape to meet the original design.\nEvery slide rail varies in some detailed design, which requires a customized production line to meet the expected profile. This means that the manufacture of a different types of roll slides may require a different machine or reconfiguration of the setup. The development takes time and costs, especially for undermount drawer slides. The profile is not as easy as contoured profile like roofing; in other words, slides roll forming requires advanced technology in manufacturing.\nOne disadvantage of drawer slides roll forming equipment is rollers can be only used to roll form one kind of profile design, which rollers must be changed when making different types or model of drawer slides profile. Complicated designs can incur large costs.\nTypes of drawer slides.\nA drawer slide or drawer runner is the part of a drawer which allows the sliding movement. Examples of uses are in home furniture hardware, office appliance, and industrial equipment, including kitchen cabinets, oven slides, rails for sliding doors, fridge slides (used for coolers, etc.\nThere are various types of drawer slide in the market to apply for different usages, price points and features. A good slide rail defined by smoothness, tight tolerance, and loading capacity.\nFeatures which may be incorporated in a drawer slide include:", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "16409745", "revid": "46249833", "url": "https://en.wikipedia.org/wiki?curid=16409745", "title": "Duplex scanning", "text": "Duplex scanning is a feature of some computer scanners, and multifunction printers (MFPs) that support duplex printing. A duplex scanner can automatically scan a sheet of paper on both sides. Scanners without this capability can only scan both sides of a sheet of paper by reinserting it manually the other way up.\nDuplex scanning is usually implemented on multifunction printers using a \"Reversing Automatic Document Feeder\" (RADF), which removes, reverses, and re-feeds the document after scanning one side. Duplex scanning is achieved on scanners by either RADF or by single pass duplex scanning using two cameras, one for each side of document; two-camera scanners scan twice as fast as a similar two-pass scanner.\nTypical duplex scanners.\nThe following table compares features for a number of duplex scanners, mostly discontinued as of 2015:", "Engineering,_Manufacturing": 0.9999908209, "qwen": "Yes"}
{"id": "16437835", "revid": "5846", "url": "https://en.wikipedia.org/wiki?curid=16437835", "title": "Thermal copper pillar bump", "text": "The thermal copper pillar bump, also known as the \"thermal bump\", is a thermoelectric device made from thin-film thermoelectric material embedded in flip chip interconnects (in particular copper pillar solder bumps) for use in electronics and optoelectronic packaging, including: flip chip packaging of CPU and GPU integrated circuits (chips), laser diodes, and semiconductor optical amplifiers (SOA). Unlike conventional solder bumps that provide an electrical path and a mechanical connection to the package, thermal bumps act as solid-state heat pumps and add thermal management functionality locally on the surface of a chip or to another electrical component. The diameter of a thermal bump is 238 μm and 60 μm high.\nThe thermal bump uses the thermoelectric effect, which is the direct conversion of temperature differences to electric voltage and vice versa. Simply put, a thermoelectric device creates a voltage when there is a different temperature on each side, or when a voltage is applied to it, it creates a temperature difference. This effect can be used to generate electricity, to measure temperature, to cool objects, or to heat them.\nFor each bump, thermoelectric cooling (TEC) occurs when a current is passed through the bump. The thermal bump pulls heat from one side of the device and transfers it to the other as current is passed through the material. This is known as the Peltier effect. The direction of heating and cooling is determined by the direction of current flow and the sign of the majority electrical carrier in the thermoelectric material. Thermoelectric power generation (TEG) on the other hand occurs when the thermal bump is subjected to a temperature gradient (i.e., the top is hotter than the bottom). In this instance, the device generates current, converting heat into electrical power. This is termed the Seebeck effect.\nThe thermal bump was developed by Nextreme Thermal Solutions as a method for integrating active thermal management functionality at the chip level in the same manner that transistors, resistors and capacitors are integrated in conventional circuit designs today. Nextreme chose the copper pillar bump as an integration strategy due to its widespread acceptance by Intel, Amkor and other industry leaders as the method for connecting microprocessors and other advanced electronics devices to various surfaces during a process referred to as “flip-chip” packaging. The thermal bump can be integrated as a part of the standard flip-chip process (Figure 1) or integrated as discrete devices.\nThe efficiency of a thermoelectric device is measured by the heat moved (or pumped) divided by the amount of electrical power supplied to move this heat. This ratio is termed the coefficient of performance or COP and is a measured characteristic of a thermoelectric device. The COP is inversely related to the temperature difference that the device produces. As you move a cooling device further away from the heat source, parasitic losses between the cooler and the heat source necessitate additional cooling power: the further the distance between source and cooler, the more cooling is required. For this reason, the cooling of electronic devices is most efficient when it occurs closest to the source of the heat generation.\nUse of the thermal bump does not displace system level cooling, which is still needed to move heat out of the system; rather it introduces a fundamentally new methodology for achieving temperature uniformity at the chip and board level. In this manner, overall thermal management of the system becomes more efficient. In addition, while conventional cooling solutions scale with the size of the system (bigger fans for bigger systems, etc.), the thermal bump can scale at the chip level by using more thermal bumps in the overall design.\nA brief history of solder and flip chip/chip scale packaging.\nSolder bumping technology (the process of joining a chip to a substrate without shorting using solder) was first conceived and implemented by IBM in the early 1960s. Three versions of this type of solder joining were developed. The first was to embed copper balls in the solder bumps to provide a positive stand-off. The second solution, developed by Delco Electronics (General Motors) in the late 1960s, was similar to embedding copper balls except that the design employed a rigid silver bump. The bump provided a positive stand-off and was attached to the substrate by means of solder that was screen-printed onto the substrate. The third solution was to use a screened glass dam near the electrode tips to act as a ‘‘stop-off’’ to prevent the ball solder from flowing down the electrode. By then the Ball Limiting Metallurgy (BLM) with a high-lead (Pb) solder system and a copper ball had proven to work well. Therefore, the ball was simply removed and the solder evaporation process extended to form pure solder bumps that were approximately 125μm high. This system became known as the controlled collapse chip connection (C3 or C4).\nUntil the mid-1990s, this type of flip-chip assembly was practiced almost exclusively by IBM and Delco. Around this time, Delco sought to commercialize its technology and formed Flip Chip Technologies with Kulicke & Soffa Industries as a partner. At the same time, MCNC (which had developed a plated version of IBM’s C4 process) received funding from DARPA to commercialize its technology. These two organizations, along with APTOS (Advanced Plating Technologies on Silicon), formed the nascent out-sourcing market.\nDuring this same time, companies began to look at reducing or streamlining their packaging, from the earlier multi-chip-on-ceramic packages that IBM had originally developed C4 to support, to what were referred to as Chip Scale Packages (CSP). There were a number of companies developing products in this area. These products could usually be put into one of two camps: either they were scaled down versions of the multi-chip on ceramic package (of which the Tessera package would be one example); or they were the streamlined versions developed by Unitive Electronics, et al. (where the package wiring had been transferred to the chip, and after bumping, they were ready to be placed).\nOne of the issues with the CSP type of package (which was intended to be soldered directly to an FR4 or flex circuit) was that for high-density interconnects, the soft solder bump provided less of a stand-off as the solder bump diameter and pitch were decreased. Different solutions were employed including one developed by Focus Interconnect Technology (former APTOS engineers), which used a high aspect ratio plated copper post to provide a larger fixed standoff than was possible for a soft solder collapse joint.\nToday, flip chip is a well established technology and collapsed soft solder connections are used in the vast majority of assemblies. The copper post stand-off developed for the CSP market has found a home in high-density interconnects for advanced micro-processors and is used today by IBM for its CPU packaging.\nCopper pillar solder bumping.\nRecent trends in high-density interconnects have led to the use of copper pillar solder bumps (CPB) for CPU and GPU packaging. CPBs are an attractive replacement for traditional solder bumps because they provide a fixed stand-off independent of pitch. This is extremely important as most of the high-end products are underfilled and a smaller standoff may create difficulties in getting the underfill adhesive to flow under the die.\nFigure 2 shows an example of a CPB fabricated by Intel and incorporated into their Presler line of microprocessors among others. The cross section shows copper and a copper pillar (approximately 60 um high) electrically connected through an opening (or via) in the chip passivation layer at the top of the picture. At the bottom is another copper trace on the package substrate with solder between the two copper layers.\nThin-film thermoelectric technology.\nThin films are thin material layers ranging from fractions of a nanometer to several micrometers in thickness. Thin-film thermoelectric materials are grown by conventional semiconductor deposition methods and fabricated using conventional semiconductor micro-fabrication techniques.\nThin-film thermoelectrics have been demonstrated to provide high heat pumping capacity that far exceeds the capacities provided by traditional bulk pellet TE products. The benefit of thin-films versus bulk materials for thermoelectric manufacturing is expressed in Equation 1. Here the Qmax (maximum heat pumped by a module) is shown to be inversely proportional to the thickness of the film, L.\nformula_1         Eq. 1\nAs such, TE coolers manufactured with thin-films can easily have 10x – 20x higher Qmax values for a given active area A. This makes thin-film TECs ideally suited for applications involving high heat-flux flows. In addition to the increased heat pumping capability, the use of thin films allows for truly novel implementation of TE devices. Instead of a bulk module that is 1–3 mm in thickness, a thin-film TEC can be fabricated less than 100 um in thickness.\nIn its simplest form, the P or N leg of a TE couple (the basic building block of all thin-film TE devices) is a layer of thin-film TE material with a solder layer above and below, providing electrical and thermal functionality.\nThermal copper pillar bump.\nThe thermal bump is compatible with the existing flip-chip manufacturing infrastructure, extending the use of conventional solder bumped interconnects to provide active, integrated cooling of a flip-chipped component using the widely accepted copper pillar bumping process. The result is higher performance and efficiency within the existing semiconductor manufacturing paradigm. The thermal bump also enables power generating capabilities within copper pillar bumps for energy recycling applications.\nThermal bumps have been shown to achieve a temperature differential of 60 °C between the top and bottom headers; demonstrated power pumping capabilities exceeding 150 W/cm2; and when subjected to heat, have demonstrated the capability to generate up to 10 mW of power per bump.\nThermal copper pillar bump structure.\nFigure 3 shows an SEM cross-section of a TE leg. Here it is demonstrated that the thermal bump is structurally identical to a CPB with an extra layer, the TE layer, incorporated into the stack-up. The addition of the TE layer transforms a standard copper pillar bump into a thermal bump. This element, when properly configured electrically and thermally, provides active thermoelectric heat transfer from one side of the bump to the other side. The direction of heat transfer is dictated by the doping type of the thermoelectric material (either a P-type or N-type semiconductor) and the direction of electric current passing through the material. This type of thermoelectric heat transfer is known as the Peltier effect. Conversely, if heat is allowed to pass from one side of the thermoelectric material to the other, a current will be generated in the material in a phenomenon known as the Seebeck effect. The Seebeck effect is essentially the reverse of the Peltier effect. In this mode, electrical power is generated from the flow of heat in the TE element. The structure shown in Figure 3 is capable of operating in both the Peltier and Seebeck modes, though not simultaneously.\nFigure 4 shows a schematic of a typical CPB and a thermal bump for comparison. These structures are similar, with both having copper pillars and solder connections. The primary difference between the two is the introduction of either a P- or N-type thermoelectric layer between two solder layers. The solders used with CPBs and thermal bumps can be any one of a number of commonly used solders including, but not limited to, Sn, SnPb eutectic, SnAg or AuSn.\nFigure 5 shows a device equipped with a thermal bump. The thermal flow is shown by the arrows labeled “heat.” Metal traces, which can be several micrometres high, can be stacked or interdigitated to provide highly conductive pathways for collecting heat from the underlying circuit and funneling that heat to the thermal bump.\nThe metal traces shown in the figure for conducting electric current into the thermal bump may or may not be directly connected to the circuitry of the chip. In the case where there are electrical connections to the chip circuitry, on-board temperature sensors and driver circuitry can be used to control the thermal bump in a closed loop fashion to maintain optimal performance. Second, the heat that is pumped by the thermal bump and the additional heat created by the thermal bump in the course of pumping that heat will need to be rejected into the substrate or board. Since the performance of the thermal bump can be improved by providing a good thermal path for the rejected heat, it is beneficial to provide high thermally conductive pathways on the backside of the thermal bump. The substrate could be a highly conductive ceramic substrate like AlN or a metal (e.g., Cu, CuW, CuMo, etc.) with a dielectric. In this case, the high thermal conductance of the substrate will act as a natural pathway for the rejected heat. The substrate might also be a multilayer substrate like a printed wiring board (PWB) designed to provide a high-density interconnect. In this case, the thermal conductivity of the PWB may be relatively poor, so adding thermal vias (e.g. metal plugs) can provide excellent pathways for the rejected heat.\nApplications.\nThermal bumps can be used in a number of different ways to provide chip cooling and power generation.\nGeneral cooling.\nThermal bumps can be evenly distributed across the surface of a chip to provide a uniform cooling effect. In this case, the thermal bumps may be interspersed with standard bumps that are used for signal, power and ground. This allows the thermal bumps to be placed directly under the active circuitry of the chip for maximum effectiveness. The number and density of thermal bumps are based on the heat load from the chip. Each P/N couple can provide a specific heat pumping (Q) at a specific temperature differential (ΔT) at a given electric current. Temperature sensors on the chip (“on board” sensors) can provide direct measurement of the thermal bump performance and provide feedback to the driver circuit.\nPrecision temperature control.\nSince thermal bumps can either cool or heat the chip depending on the current direction, they can be used to provide precision control of temperature for chips that must operate within specific temperature ranges irrespective of ambient conditions. For example, this is a common problem for many optoelectronic components.\nHotspot cooling.\nIn microprocessors, graphics processors and other high-end chips, hotspots can occur as power densities vary significantly across a chip. These hotspots can severely limit the performance of the devices. Because of the small size of the thermal bumps and the relatively high density at which they can be placed on the active surface of the chip, these structures are ideally suited for cooling hotspots. In such a case, the distribution of the thermal bumps may not need to be even. Rather, the thermal bumps would be concentrated in the area of the hotspot while areas of lower heat density would have fewer thermal bumps per unit area. In this way, cooling from the thermal bumps is applied only where needed, thereby reducing the added power necessary to drive the cooling and reducing the general thermal overhead on the system.\nPower generation.\nIn addition to chip cooling, thermal bumps can also be applied to high heat-flux interconnects to provide a constant, steady source of power for energy scavenging applications. Such a source of power, typically in the mW range, can trickle charge batteries for wireless sensor networks and other battery operated systems.", "Engineering,_Manufacturing": 0.9998972416, "qwen": "Yes"}
{"id": "12431124", "revid": "38344384", "url": "https://en.wikipedia.org/wiki?curid=12431124", "title": "Process Window Index", "text": "Process Window Index (PWI) is a statistical measure that quantifies the robustness of a manufacturing process, e.g. one which involves heating and cooling, known as a thermal process. In manufacturing industry, PWI values are used to calibrate the heating and cooling of soldering jobs (known as a thermal profile) while baked in a reflow oven.\nPWI measures how well a process fits into a user-defined process limit known as the specification limit. The specification limit is the tolerance allowed for the process and may be statistically determined. Industrially, these specification limits are known as the \"process window\", and values that a plotted inside or outside this window are known as the process window index.\nUsing PWI values, processes can be accurately measured, analyzed, compared, and tracked at the same level of statistical process control and quality control available to other manufacturing processes.\nStatistical process control.\nProcess capability is the ability of a process to produce output within specified limits. To help determine whether a manufacturing or business process is in a state of statistical control, process engineers use control charts, which help to predict the future performance of the process based on the current process.\nTo help determine the capability of a process, statistically determined upper and lower limits are drawn on either side of a process mean on the control chart. The control limits are set at three standard deviations on either side of the process mean, and are known as the upper control limit (UCL) and lower control limit (LCL) respectively. If the process data plotted on the control chart remains within the control limits over an extended period, then the process is said to be stable.\nThe tolerance values specified by the end-user are known as specification limits – the upper specification limit (USL) and lower specification limit (LSL) respectively. If the process data plotted on a control chart remains within these specification limits, then the process is considered a capable process, denoted by formula_1.\nManufacturing industry has developed customized specification limits known as Process Windows. Within this process window, values are plotted. The values relative to the process mean of the window are known as the Process Window Index. By using PWI values, processes can be accurately measured, analyzed, compared, and tracked at the same level of statistical process control and quality control available to other manufacturing processes.\nControl limits.\nControl limits, also known as natural process limits, are horizontal lines drawn on a statistical process control chart, usually at a distance of ±3 standard deviations of the plotted statistic's mean, used to judge the stability of a process.\nControl limits should not be confused with \"tolerance limits\" or \"specifications,\" which are completely independent of the distribution of the plotted sample statistic. Control limits describe what a process is capable of producing (sometimes referred to as the “voice of the process”), while tolerances and specifications describe how the product should perform to meet the customer's expectations (referred to as the “voice of the customer”).\nUse.\nControl limits are used to detect signals in process data that indicate that a process is not in control and, therefore, not operating predictably. A value in excess of the control limit indicates a special cause is affecting the process. \nTo detect signals one of several rule sets may be used . One specification outlines that a signal is defined as any single point outside of the control limits. A process is also considered out of control if there are seven consecutive points, still inside the control limits but on one single side of the mean.\nFor normally distributed statistics, the area bracketed by the control limits will on average contain 99.73% of all the plot points on the chart, as long as the process is and remains in statistical control. A false-detection rate of at least 0.27% is therefore expected.\nIt is often not known whether a particular process generates data that conform to particular distributions, but the Chebyshev's inequality and the Vysochanskij–Petunin inequality allow the inference that for any unimodal distribution at least 95% of the data will be encapsulated by limits placed at 3 sigma.\nPWI in electronics manufacturing.\nAn example of a process to which the PWI concept may be applied is soldering. In soldering, a thermal profile is the set of time-temperature values for a variety of processes such as slope, thermal soak, reflow, and peak. \nEach thermal profile is ranked on how it fits in a process window (the specification or tolerance limit). Raw temperature values are normalized in terms of a percentage relative to both the process mean and the window limits. The center of the process window is defined as zero, and the extreme edges of the process window are ±99%. A PWI greater than or equal to 100% indicates that the profile does not process the product within specification. A PWI of 99% indicates that the profile runs at the edge of the process window. For example, if the process mean is set at 200 °C, with the process window calibrated at 180 °C and 220 °C respectively; then a measured value of 188 °C translates to a process window index of −60%. A lower PWI value indicates a more robust profile. For maximum efficiency, separate PWI values are computed for peak, slope, reflow, and soak processes of a thermal profile. \nTo avoid thermal shock affecting production, the steepest slope in the thermal profile is determined and leveled. Manufacturers use custom-built software to accurately determine and decrease the steepness of the slope. In addition, the software also automatically recalibrates the PWI values for the peak, slope, reflow, and soak processes. By setting PWI values, engineers can ensure that the reflow soldering work does not overheat or cool too quickly.\nFormula.\nThe Process Window Index is calculated as the worst case (i.e. highest number) in the set of thermal profile data. For each profile statistic the percentage used of the respective process window is calculated, and the worst case (i.e. highest percentage) is the PWI.\nFor example, a thermal profile with three thermocouples, with four profile statistics logged for each thermocouple, would have a set of twelve statistics for that thermal profile. In this case, the PWI would be the highest value among the twelve percentages of the respective process windows. \nThe formula to calculate PWI is:\nwhere:", "Engineering,_Manufacturing": 0.999968648, "qwen": "Yes"}
{"id": "2360617", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=2360617", "title": "Bumpless Build-up Layer", "text": "Bumpless Build-up Layer or BBUL is a processor packaging technology developed by Intel. It is bumpless, because it does not use the usual tiny solder bumps to attach the silicon die to the processor package wires. It has build-up layers, because is grown or built up around the silicon die. The usual way is to manufacture them separately and bond them together.\nIt was presented in October 2001. It should have been a key component in the 8 GHz and 15 GHz processors that should have been in the market by 2005 and 2007 respectively. Also 20 GHz should have been possible before the year 2010. The BBUL is not needed yet because there is no longer the clock-frequency competition.", "Engineering,_Manufacturing": 0.9992879033, "qwen": "Yes"}
{"id": "2361092", "revid": "38448542", "url": "https://en.wikipedia.org/wiki?curid=2361092", "title": "Reconfigurable manufacturing system", "text": "A reconfigurable manufacturing system (RMS) is one designed at the outset for rapid change in its structure, as well as its hardware and software components, in order to quickly adjust its production capacity and functionality within a part family in response to sudden market changes or intrinsic system change.\nFrom 1996 to 2007 Yoram Koren received an NSF grant of $32.5 million to develop the RMS science-base and its software and hardware tools, which were implemented in the automotive, aerospace, and engine factories.\nThe term reconfigurability in manufacturing was likely coined by Kusiak and Lee.\nThe RMS, as well as one of its components—the reconfigurable machine tool (RMT)—were invented in 1998 in the Engineering Research Center for Reconfigurable Manufacturing Systems (ERC/RMS) at the University of Michigan College of Engineering. The RMS goal is summarized by the statement: \"Exactly the capacity and functionality needed, exactly when needed\".\nIdeal reconfigurable manufacturing systems possess six core RMS characteristics: modularity, integrability, customized flexibility, scalability, convertibility, and diagnosability. A typical RMS will have several of these characteristics, though not necessarily all. When possessing these characteristics, RMS increases the speed of responsiveness of manufacturing systems to unpredicted events, such as sudden market demand changes or unexpected machine failures.. The RMS facilitates a quick production launch of new products, and allows for adjustment of production quantities that might unexpectedly vary. The ideal reconfigurable system provides exactly the functionality and production capacity needed, and can be economically adjusted exactly when needed. These systems are designed and operated according to Yoram Koren's RMS principles.\nThe components of RMS are CNC machines, reconfigurable machine tools, reconfigurable inspection machines and material transport systems (such as gantries and conveyors) that connect the machines to form the system. Different arrangements and configurations of these machines will affect the system's productivity. A collection of mathematical tools, which are defined as the RMS science base, may be utilized to maximize system productivity with the smallest possible number of machines.\nRationale for RMS.\nGlobalization has created a new landscape for industry, one of fierce competition, short windows of market opportunity, and frequent changes in product demand. This change presents both a threat and an opportunity. To capitalize on the opportunity, industry needs to possess manufacturing systems that can produce a wide range of products within a product family. That range must meet the requirements of multiple countries and various cultures, not just one regional market. A design for the right mix of products must be coupled with the technical capabilities that allow for quick changeover of product mix and quantities that might vary dramatically, even on a monthly basis. Reconfigurable manufacturing systems have these capabilities.\nRMS System Architecture and Operation.\nThe system architecture of a typical RMS is shown below. \nThe system is composed of stages: 10, 20, 30, 40, etc. Each stage consists of identical machines, such as CNC milling machines, or RMT machines. The system produces one product, for example, an automotive engine block or a cylinder head. The manufactured product moves on the horizontal conveyor. Then Gantry-10 grips the product and brings it to one of CNC-10. When CNC-10 finishes the processing, Gantry-10 moves it back to the conveyor. The conveyor moves the product to Gantry-20, which grips the product and load it on the RMT-20, and so on. Inspection machines are placed at several stages, and at the end of the manufacturing system. \nRMS is defined as a “system designed at the outset for rapid changes in its structure.” In practice this feature is implemented by designing an open space with an access to the gantry at each stage. These spaces enable matching rapidly higher market demand by adding machines in these spaces, which increases production rate to match the demand. \nThe product may move during its production in many production paths. Three paths are shown in the figure. Although the CNC machines at each stage are identical, in practice there are small variations in the precision of identical machines, which create accumulated errors in the manufactured product. The magnitude of the error depends on the path in which the product moved; each path has its own “stream-of-variations” (a term coined by Y. Koren).\nRMS characteristics.\nIdeal reconfigurable manufacturing systems possess six core characteristics: modularity, integrability, customized flexibility, scalability, convertibility, and diagnosability. These characteristics, which were introduced by professor Yoram Koren in 1995, apply to the design of whole manufacturing systems, as well as to some of its components: reconfigurable machines, their controllers, and system control software.\nModularity refers to the modules that reconfigurable manufacturing systems consist of\".\" At the system level the machines are modules. At the machine level the axes of motion are modules (see the RMT Figure). The system control may be composed of control modules. Modules are easier to maintain and update.\nIntegrability is the ability to rapidly integrate modules by mechanical, informational, and control interfaces that enable module integration and communication.  At the system level the machines are the modules that are integrated via material transport systems (such as conveyors and gantries) to form a reconfigurable manufacturing system.\nCustomization allows the design of system flexibility just around a product family, obtaining thereby customized-flexibility, as opposed to the general flexibility of FMS. Customization allows a reduction in the investment cost without sacrificing performance.\nConvertibility is the ability to easily transform the functionality of existing systems, machines, or controls to suit new production requirements. Examples included changing a machine in the system to another type of machine to respond to  a new required functionality, or  switching spindles on a milling machine (e.g., from low-torque high-speed spindle for aluminum to high-torque low-speed spindle for titanium).\nScalability is the ability to easily change production capacity by adding (or reducing) manufacturing resources. Scalability of a manufacturing system is increased by adding machines to expand the system production rate to match a sudden market growth. Adding machines requires extending the reach of the station gantries.\nDiagnosability is the ability to automatically detect and diagnose the source of the manufactured product quality or precision defects. This automatic diagnosis  allows rapid correction of the defects. The RMS must be designed with product inspection machines embedded at optimal locations in the system. \nRMS principles.\nReconfigurable manufacturing systems operate according to a set of basic principles formulated by professor Yoram Koren and are called Koren's RMS principles. The more of these principles applicable to a given manufacturing system, the more reconfigurable is that system. The RMS principles are:\nRMS and FMS.\nReconfigurable manufacturing systems (RMS) and flexible manufacturing systems (FMS) have different goals. FMS aims at increasing the variety of parts produced. RMS aims at increasing the speed of responsiveness to market changes and customer's demand. RMS is also flexible, but only to a limited extent—its flexibility is confined to only that necessary to produce a part family. This is the \"customized flexibility\" or the customization characteristic, which is not the general flexibility that FMS offers. The customized flexibility enables higher production rates. Other important advantages of RMS are rapid scalability to the desired volume, and convertibility, which are obtained within reasonable cost to manufacturers. The best application of FMS is found in production of small sets of products [see Wikipedia].\nRMS science base.\nThe RMS technology is based on a systematic approach to the design and operation of reconfigurable manufacturing systems. The approach consists of key elements, the compilation of which is called the RMS science base. These elements are summarized below.", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "2366787", "revid": "1223123", "url": "https://en.wikipedia.org/wiki?curid=2366787", "title": "Water jet cutter", "text": "A water jet cutter, also known as a water jet or waterjet, is an industrial tool capable of cutting a wide variety of materials using an extremely high-pressure jet of water, or a mixture of water and an abrasive substance. The term abrasive jet refers specifically to the use of a mixture of water and an abrasive to cut hard materials such as metal, stone or glass, while the terms pure waterjet and water-only cutting refer to waterjet cutting without the use of added abrasives, often used for softer materials such as wood or rubber.\nWaterjet cutting is often used during the fabrication of machine parts. It is the preferred method when the materials being cut are sensitive to the high temperatures generated by other methods; examples of such materials include plastic and aluminium. Waterjet cutting is used in various industries, including mining and aerospace, for cutting, shaping, and reaming.\nHistory.\nWaterjet.\nWhile using high-pressure water for erosion dates back as far as the mid-1800s with hydraulic mining, it was not until the 1930s that narrow jets of water started to appear as an industrial cutting device. In 1933, the Paper Patents Company in Wisconsin developed a paper metering, cutting, and reeling machine that used a diagonally moving waterjet nozzle to cut a horizontally moving sheet of continuous paper. These early applications were at low pressure and restricted to soft materials like paper.\nWaterjet technology evolved in the post-war era as researchers around the world searched for new methods of efficient cutting systems. In 1956, Carl Johnson of Durox International in Luxembourg developed a method for cutting plastic shapes using a thin stream high-pressure water jet, but those materials, like paper, were soft materials. In 1958, Billie Schwacha of North American Aviation developed a system using ultra-high-pressure liquid to cut hard materials. This system used a pump to deliver a hypersonic liquid jet that could cut high-strength alloys such as PH15-7-MO stainless steel. Used to cut honeycomb laminate for the Mach 3 North American XB-70 Valkyrie, this cutting method resulted in delaminating at high speed, requiring changes to the manufacturing process.\nWhile not effective for the XB-70 project, the concept was valid and further research continued to evolve waterjet cutting. In 1962, Philip Rice of Union Carbide explored using a pulsing waterjet at up to to cut metals, stone, and other materials. Research by S.J. Leach and G.L. Walker in the mid-1960s expanded on traditional coal waterjet cutting to determine the ideal nozzle shape for high-pressure waterjet cutting of stone, and Norman Franz in the late 1960s focused on waterjet cutting of soft materials by dissolving long-chain polymers in the water to improve the cohesiveness of the jet stream. In the early 1970s, the desire to improve the durability of the waterjet nozzle led Ray Chadwick, Michael Kurko, and Joseph Corriveau of the Bendix Corporation to come up with the idea of using corundum crystal to form a waterjet orifice, while Norman Franz expanded on this and created a waterjet nozzle with an orifice as small as that operated at pressures up to . John Olsen, along with George Hurlburt and Louis Kapcsandy at Flow Research (later Flow Industries), further improved the commercial potential of the water jet by showing that treating the water beforehand could increase the operational life of the nozzle.\nHigh pressure.\nHigh-pressure vessels and pumps became affordable and reliable with the advent of steam power. By the mid-1800s, steam locomotives were common and the first efficient steam-driven fire engine was operational. By the turn of the century, high-pressure reliability improved, with locomotive research leading to a sixfold increase in boiler pressure, some reaching . Most high-pressure pumps at this time, though, operated around .\nHigh-pressure systems were further shaped by the aviation, automotive, and oil industries. Aircraft manufacturers such as Boeing developed seals for hydraulically boosted control systems in the 1940s, while automotive designers followed similar research for hydraulic suspension systems. Higher pressures in hydraulic systems in the oil industry also led to the development of advanced seals and packing to prevent leaks.\nThese advances in seal technology, plus the rise of plastics in the post-war years, led to the development of the first reliable high-pressure pump. The invention of Marlex by Robert Banks and John Paul Hogan of the Phillips Petroleum Company required a catalyst to be injected into the polyethylene. McCartney Manufacturing Company in Baxter Springs, Kansas, began manufacturing these high-pressure pumps in 1960 for the polyethylene industry. Flow Industries in Kent, Washington set the groundwork for commercial viability of waterjets with John Olsen’s development of the high-pressure fluid intensifier in 1973, a design that was further refined in 1976. Flow Industries then combined the high-pressure pump research with their waterjet nozzle research and brought waterjet cutting into the manufacturing world.\nAbrasive waterjet.\nWhile cutting with water is possible for soft materials, adding an abrasive turned the water jet into a modern machining tool for all materials. This began in 1935 when the idea of adding an abrasive to the water stream was developed by Elmo Smith for liquid abrasive blasting. Smith’s design was further refined by Leslie Tirrell of the Hydroblast Corporation in 1937, resulting in a nozzle design that created a mix of high-pressure water and abrasive for the purpose of wet blasting.\nThe first publications on modern abrasive waterjet (AWJ) cutting were published by Mohamed Hashish in the 1982 BHR proceedings showing, for the first time, that waterjets with relatively small amounts of abrasives are capable of cutting hard materials such as steel and concrete. The March 1984 issue of the Mechanical Engineering magazine showed more details and materials cut with AWJ such as titanium, aluminium, glass, and stone. Mohamed Hashish was awarded a patent on forming AWJ in 1987. Hashish, who also coined the new term \"abrasive waterjet\", and his team continued to develop and improve the AWJ technology and its hardware for many applications. A critical development was creating a durable mixing tube that could withstand the power of the high-pressure AWJ, and it was Boride Products (now Kennametal) development of their ROCTEC line of ceramic tungsten carbide composite tubes that significantly increased the operational life of the AWJ nozzle. Current work on AWJ nozzles is on micro abrasive waterjets so that cutting with jets smaller than in diameter can be commercialized.\nWorking with Ingersoll-Rand Waterjet Systems, Michael Dixon implemented the first production practical means of cutting titanium sheets—an abrasive waterjet system very similar to those in widespread use today. By January 1989, that system was being run 24 hours a day producing titanium parts for the B-1B largely at Rockwell's North American Aviation facility in Newark, Ohio.\nToday, there are two different types of Abrasive Waterjets:\nAbrasive Water Suspension Jet (AWSJ) cutting.\nThe Abrasive Water Suspension Jet (AWSJ) - often called “Slurry Jet” or “Water Abrasive Suspension (WAS) jet” - is a specific type of abrasive water jet, which is used for waterjet cutting. In contrast to the abrasive water injector jet (AWIJ), the abrasive water suspension jet (AWSJ) is characterised by the fact that the mixing of abrasive and water takes place before the nozzle. This has the effect that, in contrast to AWIJ, the jet consists of only two components: the water and the abrasive.\nSince there are only 2 components (water and abrasive) in the AWSJ, the acceleration of the abrasive grains by the water takes place with a significantly increased efficiency compared to the AWIJ. The abrasive grains become faster with the WASS than with the WAIS for the same hydraulic power of the system. Therefore, comparatively deeper or faster cuts can be made with the AWSJ.\nAWSJ cutting, in contrast to the AWIJ cutting process described below, can also be used for mobile cutting applications and cutting underwater, in addition to machining demanding materials. Examples include bomb disposal s well as the dismantling of offshore installations or the dismantling of reactor pressure vessel installations in nuclear power plants.\nAbrasive Water Injector Jet (AWIJ) cutting.\nThe AWIJ is generated by a water jet that passes through a mixing chamber (a cavity) after exiting the water nozzle and enters a focusing tube at the exit of the mixing chamber. The interaction of the water jet in the mixing chamber with the air inside creates negative pressure, the water jet entrains air particles. This negative pressure is used for the pneumatic transport of the abrasive into the chamber (the abrasive is led to a lateral opening (bore) of the mixing chamber by means of a hose).\nAfter contact with the abrasive material in the mixing chamber with the water jet, the individual abrasive grains are accelerated and entrained in the direction of the focusing tube. The air used as a carrier medium for transporting the abrasive into the mixing chamber also becomes part of the AWIJ, which now consists of three components (water - abrasive - air). In the focusing tube, which is (should be) optimised in its length for this purpose, the abrasive is further accelerated (energy transfer from the water to the abrasive grain) and the AWIJ ideally leaves the focusing tube at the maximum possible abrasive grain speed.\nWaterjet control.\nAs waterjet cutting moved into traditional manufacturing shops, controlling the cutter reliably and accurately was essential. Early waterjet cutting systems adapted traditional systems such as mechanical pantographs and CNC systems based on John Parsons’ 1952 NC milling machine and running G-code. Challenges inherent to waterjet technology revealed the inadequacies of traditional G-Code. The accuracy depends on varying the speed of the nozzle as it approaches corners and details. Creating motion control systems to incorporate those variables became a major innovation for leading waterjet manufacturers in the early 1990s, with John Olsen of OMAX Corporation developing systems to precisely position the waterjet nozzle while accurately specifying the speed at every point along the path, and also utilizing common PCs as a controller. The largest waterjet manufacturer, Flow International (a spinoff of Flow Industries), recognized the benefits of that system and licensed the OMAX software, with the result that the vast majority of waterjet cutting machines worldwide are simple to use, fast, and accurate.\nOperation.\nAll waterjets follow the same principle of using high-pressure water focused into a beam by a nozzle. Most machines accomplish this by first running the water through a high-pressure pump. There are two types of pumps used to create this high pressure; an intensifier pump and a direct drive or crankshaft pump. A direct drive pump works much like a car engine, forcing water through high-pressure tubing using plungers attached to a crankshaft. An intensifier pump creates pressure by using hydraulic oil to move a piston forcing the water through a tiny hole. The water then travels along the high-pressure tubing to the nozzle of the waterjet. In the nozzle, the water is focused into a thin beam by a jewel orifice. This beam of water is ejected from the nozzle, cutting through the material by spraying it with the jet of speed on the order of Mach 3, around . The process is the same for abrasive waterjets until the water reaches the nozzle. Here abrasives such as garnet and aluminium oxide, are fed into the nozzle via an abrasive inlet. The abrasive then mixes with the water in a mixing tube and is forced out the end at high pressure.\nBenefits.\nAn important benefit of the water jet is the ability to cut material without interfering with its inherent structure, as there is no \"heat-affected zone\" (HAZ). Minimizing the effects of heat allows metals to be cut without warping, affecting tempers, or changing intrinsic properties. Sharp corners, bevels, pierce holes, and shapes with minimal inner radii are all possible.\nWater jet cutters are also capable of producing intricate cuts in material. With specialized software and 3-D machining heads, complex shapes can be produced.\nThe kerf, or width, of the cut can be adjusted by swapping parts in the nozzle, as well as changing the type and size of the abrasive. Typical abrasive cuts have a kerf in the range of , but can be as narrow as . Non-abrasive cuts are normally , but can be as small as , which is approximately that of a human hair. These small jets can permit small details in a wide range of applications.\nWater jets are capable of attaining accuracy down to and repeatability down to .\nDue to its relatively narrow kerf, water jet cutting can reduce the amount of scrap material produced, by allowing uncut parts to be nested more closely together than traditional cutting methods. Water jets use approximately per minute (depending on the cutting head's orifice size), and the water can be recycled using a closed-loop system. Waste water usually is clean enough to filter and dispose of down a drain. The garnet abrasive is a non-toxic material that can be mostly recycled for repeated use; otherwise, it can usually be disposed of in a landfill. Water jets also produce fewer airborne dust particles, smoke, fumes, and contaminants, reducing operator exposure to hazardous materials.\nMeatcutting using waterjet technology eliminates the risk of cross contamination since the contact medium is discarded.\nVersatility.\nBecause the nature of the cutting stream can be easily modified the water jet can be used in nearly every industry; there are many different materials that the water jet can cut. Some of them have unique characteristics that require special attention when cutting.\nMaterials commonly cut with a water jet include textiles, rubber, foam, plastics, leather, composites, stone, tile, glass, metals, food, paper and much more. \"Most ceramics can also be cut on an abrasive water jet as long as the material is softer than the abrasive being used (between 7.5 and 8.5 on the Mohs scale)\". Examples of materials that cannot be cut with a water jet are tempered glass and diamonds. Water jets are capable of cutting up to of metals and of most materials, though in specialized coal mining applications, water jets are capable of cutting up to using a nozzle.\nSpecially designed water jet cutters are commonly used to remove excess bitumen from road surfaces that have become the subject of binder flushing. Flushing is a natural occurrence caused during hot weather where the aggregate becomes level with the bituminous binder layer creating a hazardously smooth road surface during wet weather.\nAvailability.\nCommercial water jet cutting systems are available from manufacturers all over the world, in a range of sizes, and with water pumps capable of a range of pressures. Typical water jet cutting machines have a working envelope as small as a few square feet, or up to hundreds of square feet. Ultra-high-pressure water pumps are available from as low as up to .\nProcess.\nThere are six main process characteristics of water jet cutting:\nTemperature is not much of a factor because the water used also acts as a coolant.\nEdge quality.\nEdge quality for water jet cut parts is defined with the quality numbers Q1 through Q5. Lower numbers indicate rougher edge finish; higher numbers are smoother. For thin materials, the difference in cutting speed for Q1 could be as much as 3 times faster than the speed for Q5. For thicker materials, Q1 could be 6 times faster than Q5. For example, thick aluminium Q5 would be and Q1 would be , 5.8 times faster.\nMulti-axis cutting.\nIn 1987, Ingersoll-Rand Waterjet Systems offered a 5-axis pure-water waterjet cutting system called the Robotic Waterjet System. The system was an overhead gantry design, similar in overall size to the HS-1000.\nWith recent advances in control and motion technology, 5-axis water jet cutting (abrasive and pure) has become a reality. Where the normal axes on a water jet are named Y (back/forth), X (left/right) and Z (up/down), a 5-axis system will typically add an A axis (angle from perpendicular) and C axis (rotation around the Z-axis). Depending on the cutting head, the maximum cutting angle for the A axis can be anywhere from 55, 60, or in some cases even 90 degrees from vertical. As such, 5-axis cutting opens up a wide range of applications that can be machined on a water jet cutting machine.\nA 5-axis cutting head can be used to cut 4-axis parts, where the bottom surface geometries are shifted a certain amount to produce the appropriate angle and the Z-axis remains at one height. This can be useful for applications like weld preparation where a bevel angle needs to be cut on all sides of a part that will later be welded, or for taper compensation purposes where the kerf angle is transferred to the waste material – thus eliminating the taper commonly found on water jet-cut parts. A 5-axis head can cut parts where the Z-axis is also moving along with all the other axes. This full 5-axis cutting could be used for cutting contours on various surfaces of formed parts.\nBecause of the angles that can be cut, part programs may need to have additional cuts to free the part from the sheet. Attempting to slide a complex part at a severe angle from a plate can be difficult without appropriate relief cuts.", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "33577624", "revid": "46118918", "url": "https://en.wikipedia.org/wiki?curid=33577624", "title": "Ujiarpur Assembly constituency", "text": "Ujiarpur Assembly constituency is an assembly constituency in Samastipur district in the Indian state of Bihar. The constituency was formed following the Delimitation Order of 2008.\nOverview.\nAs per Delimitation of Parliamentary and Assembly constituencies Order, 2008, No. 134 Ujiarpur Assembly constituency is composed of the following: Ujiarpur community development block; Sultanpur Ghataho,\nChakbahauddin, Mokhtiyarpur Salkhani, Panr, Harishankarpur, Kewanta, Nagargama, Pagra, Nawada, Basariya gram panchayats and Dalsinghsarai notified area of Dalsinghsarai CD Block.\nUjiarpur Assembly constituency is part of No. 22 Ujiarpur (Lok Sabha constituency).\nElection results.\n2015.\nIn the 2015 state assembly elections, Alok Kumar Mehta of RJD won the newly constituted Ujiarpur seat.", "Engineering,_Manufacturing": 0.9961106777, "qwen": "Yes"}
{"id": "6220531", "revid": "327592", "url": "https://en.wikipedia.org/wiki?curid=6220531", "title": "Electronic packaging", "text": "Electronic packaging is the design and production of enclosures for electronic devices ranging from individual semiconductor devices up to complete systems such as a mainframe computer. Packaging of an electronic system must consider protection from mechanical damage, cooling, radio frequency noise emission and electrostatic discharge. Product safety standards may dictate particular features of a consumer product, for example, external case temperature or grounding of exposed metal parts. Prototypes and industrial equipment made in small quantities may use standardized commercially available enclosures such as card cages or prefabricated boxes. Mass-market consumer devices may have highly specialized packaging to increase consumer appeal. Electronic packaging is a major discipline within the field of mechanical engineering.\nDesign.\nElectronic packaging can be organized by levels:\nThe same electronic system may be packaged as a portable device or adapted for fixed mounting in an instrument rack or permanent installation. Packaging for aerospace, marine, or military systems imposes different types of design criteria.\nElectronic packaging relies on mechanical engineering principles such as dynamics, stress analysis, heat transfer and fluid mechanics. High-reliability equipment often must survive drop tests, loose cargo vibration, secured cargo vibration, extreme temperatures, humidity, water immersion or spray, rain, sunlight (UV, IR and visible light), salt spray, explosive shock, and many more. These requirements extend beyond and interact with the electrical design.\nAn electronics assembly consists of component devices, circuit card assemblies (CCAs), connectors, cables and components such as transformers, power supplies, relays, switches, etc. that may not mount on the circuit card.\nMany electrical products require the manufacturing of high-volume, low-cost parts such as enclosures or covers by techniques such as injection molding, die casting, investment casting, and so on. The design of these products depends on the production method and require careful consideration of dimensions and tolerances and tooling design. Some parts may be manufactured by specialized processes such as plaster- and sand-casting of metal enclosures. \nIn the design of electronic products, electronic packaging engineers perform analyses to estimate such things as maximum temperatures for components, structural resonant frequencies, and dynamic stresses and deflections under worst-case environments. Such knowledge is important to prevent immediate or premature electronic product failures.\nDesign considerations.\nA designer must balance many objectives and practical considerations when selecting packaging methods.\nPackaging materials.\nSheet metal.\nPunched and formed sheet metal is one of the oldest types of electronic packaging. It can be mechanically strong, provides electromagnetic shielding when the product requires that feature, and is easily made for prototypes and small production runs with little custom tooling expense.\nCast metal.\nGasketed metal castings are sometimes used to package electronic equipment for exceptionally severe environments, such as in heavy industry, aboard ship, or deep under water. Aluminum die castings are more common than iron or steel sand castings.\nMachined metal.\nElectronic packages are sometimes made by machining solid blocks of metal, usually aluminum, into complex shapes. They are fairly common in microwave assemblies for aerospace use, where precision transmission lines require complex metal shapes, in combination with hermetically sealed housings. Quantities tend to be small; sometimes only one unit of a custom design is required. Piece part costs are high, but there is little or no cost for custom tooling, and first-piece deliveries can take as little as half a day. The tool of choice is a numerically controlled vertical milling machine, with automatic translation of computer-aided design (CAD) files to toolpath command files.\nMolded plastic.\nMolded plastic cases and structural parts can be made by a variety of methods, offering tradeoffs in piece part cost, tooling cost, mechanical and electrical properties, and ease of assembly. Examples are injection molding, transfer molding, vacuum forming, and die cutting. Pl can be post-processed to provide conductive surfaces.\nPotting.\nAlso called \"encapsulation\", potting consists of immersing the part or assembly in a liquid resin, then curing it. Another method puts the part or assembly in a mold, and potting compound is poured in it, and after curing, the mold is not removed, becoming part of the part or assembly. Potting can be done in a pre-molded potting shell, or directly in a mold. Today it is most widely used to protect semiconductor components from moisture and mechanical damage, and to serve as a mechanical structure holding the lead frame and the chip together. In earlier times it was often used to discourage reverse engineering of proprietary products built as printed circuit modules. It is also commonly used in high voltage products to allow live parts to be placed closer together (eliminating corona discharges due to the potting compound's high dielectric strength), so that the product can be smaller. This also excludes dirt and conductive contaminants (such as impure water) from sensitive areas. Another use is to protect deep-submergence items such as sonar transducers from collapsing under extreme pressure, by filling all voids. Potting can be rigid or soft. When void-free potting is required, it is common practice to place the product in a vacuum chamber while the resin is still liquid, hold a vacuum for several minutes to draw the air out of internal cavities and the resin itself, then release the vacuum. Atmospheric pressure collapses the voids and forces the liquid resin into all internal spaces. Vacuum potting works best with resins that cure by polymerization, rather than solvent evaporation.\nPorosity sealing or impregnation.\nPorosity Sealing or Resin Impregnation is similar to potting, but doesn't use a shell or a mold. Parts are submerged in a polymerizable monomer or solvent-based low viscosity plastic solution. The pressure above the fluid is lowered to a full vacuum. After the vacuum is released, the fluid flows into the part. When the part is withdrawn from the resin bath, it is drained and/or cleaned and then cured. Curing can consist of polymerizing the internal resin or evaporating the solvent, which leaves an insulating dielectric material between different voltage components. Porosity sealing (Resin Impregnation) fills all interior spaces, and may or may not leave a thin coating on the surface, depending on the wash/rinse performance. The main application of vacuum impregnation porosity sealing is in boosting the dielectric strength of transformers, solenoids, lamination stacks or coils, and some high voltage components. It prevents ionization from forming between closely spaced live surfaces and initiating failure.\nLiquid filling.\nLiquid filling is sometimes used as an alternative to potting or impregnation. It's usually a dielectric fluid, chosen for chemical compatibility with the other materials present. This method is used mostly in very large electrical equipment such as utility transformers, to increase breakdown voltage. It can also be used to improve heat transfer, especially if allowed to circulate by natural convection or forced convection through a heat exchanger. Liquid filling can be removed for repair much more easily than potting.\nConformal coating.\nConformal coating is a thin insulating coating applied by various methods. It provides mechanical and chemical protection of delicate components. It's widely used on mass-produced items such as axial-lead resistors, and sometimes on printed circuit boards. It can be very economical, but somewhat difficult to achieve consistent process quality.\nGlob-top.\nGlob-top is a variant of conformal coating used in chip-on-board assembly (COB). It consists of a drop of specially formulated epoxy or resin deposited over a semiconductor chip and its wire bonds, to provide mechanical support and exclude contaminants such as fingerprint residues which could disrupt circuit operation. It is most commonly used in electronic toys and low-end devices.\nChip on board.\nSurface-mounted LEDs are frequently sold in chip-on-board (COB) configurations. In these, the individual diodes are mounted in an array that allows the device to produce a greater amount of luminous flux with greater ability to dissipate the resulting heat in an overall smaller package than can be accomplished by mounting LEDs, even surface mount types, individually on a circuit board.\nHermetic metal/glass cases.\nHermetic metal packaging began life in the vacuum tube industry, where a totally leak-proof housing was essential to operation. This industry developed the glass-seal electrical feedthrough, using alloys such as Kovar to match the coefficient of expansion of the sealing glass so as to minimize mechanical stress on the critical metal-glass bond as the tube warmed up. Some later tubes used metal cases and feedthroughs, and only the insulation around the individual feedthroughs used glass. Today, glass-seal packages are used mostly in critical components and assemblies for aerospace use, where leakage must be prevented even under extreme changes in temperature, pressure, and humidity.\nHermetic ceramic packages.\nPackages consisting of a lead frame embedded in a vitreous paste layer between flat ceramic top and bottom covers are more convenient than metal/glass packages for some products, but give equivalent performance. Examples are integrated circuit chips in ceramic Dual In-line Package form, or complex hybrid assemblies of chip components on a ceramic base plate. This type of packaging can also be divided into two main types: multilayer ceramic packages (like LTCC and HTCC) and pressed ceramic packages.\nPrinted circuit assemblies.\nPrinted circuits are primarily a technology for connecting components together, but they also provide mechanical structure. In some products, such as computer accessory boards, they're all the structure there is. This makes them part of the universe of electronic packaging.\nReliability evaluation.\nA typical reliability qualification includes the following types of environmental stresses:\nHygrothermal test is performed in chambers with temperature and humidity. It is an environmental stress test used in evaluating product reliability. The typical hygrothermal test is 85˚C temperature and 85% relative humidity (abbr. 85˚C/85%RH). During the test, the sample is periodically taken out to test its mechanical or electrical properties. Some research works related to hygrothermal test can be seen in the references. ", "Engineering,_Manufacturing": 0.9999928474, "qwen": "Yes"}
{"id": "6235968", "revid": "24697223", "url": "https://en.wikipedia.org/wiki?curid=6235968", "title": "Head restraint", "text": "Head restraints (also called headrests) are an automotive safety feature, attached or integrated into the top of each seat to limit the rearward movement of the adult occupant's head, relative to the torso, in a collision — to prevent or mitigate whiplash or injury to the cervical vertebrae. Since their mandatory introduction in some countries beginning in the late 1960s, head restraints have prevented or mitigated thousands of serious injuries.\nA patent for an automobile \"headrest\" was granted to Benjamin Katz, a resident of Oakland, California, in 1921. Additional patents for such devices were issued in 1930 and in 1950, and subsequently. The major U. K. supplier of head restraints, Karobes, filed patents in the late 1950s and was still competitive in 1973 when British tests evaluated the quality of these devices.\nOptional head restraints began appearing on North American cars in the mid-1960s, and were mandated by the U.S. National Highway Traffic Safety Administration (NHTSA) in all new cars sold in the U.S. after January 1, 1969. The U.S. regulation, called Federal Motor Vehicle Safety Standard 202, requires that head restraints meet one of the following two standards of performance, design, and construction:\nAn evaluation performed by NHTSA in 1982 on passenger cars found that \"integral\" head restraints—a seat back extending high enough to meet the height requirement—reduces injury by 17 percent, while adjustable head restraints, attached to the seat back by one or more sliding metal shafts, reduce injury by 10 percent. NHTSA has said this difference may be due to adjustable restraints being improperly positioned.\nReason for discomfort.\nHeadrests are uncomfortable when they push the head forward. In such case there is effectively no gap behind the head and the headrest, or more technically, there's a 'negative' backset (or gap) as the headrest interferes with their natural neutral posture. Data shows that 16% of the population will experience headrest discomfort because of this issue. The rest of the population experiences no discomfort because there is no contact with the headrest, i.e. there is a gap between the head and headrest.\nHeadrests are designed this way because the regulated specs for headrests are set for the 'average' body posture. When the U.S. National Highway Traffic Safety Administration (NHTSA) revised the standard which governs head restraints for all new cars manufactured after 2008, it established for the first time a requirement for the fore-aft position, or \"backset\". The backset requirements was set at a 55mm (2.1 in) gap behind the head of the \"average\" body posture. By definition, not everyone has the 'average' posture. The specs will therefore cause issues for this 16% subset of the population.\nWhiplash protection.\nThe focus of preventive measures to date has been on the design of car seats, primarily through the introduction of head restraints, often called headrests. This approach is potentially problematic given the underlying assumption that purely mechanical factors cause whiplash injuries — an unproven theory. So far the injury reducing effects of head restraints appears to have been low, approximately 5–10%, because car seats have become stiffer in order to increase crashworthiness of cars in high-speed rear-end collisions which in turn could increase the risk of whiplash injury in low-speed rear impact collisions. Improvements in the geometry of car seats through better design and energy absorption could offer additional benefits. Active devices move the body in a crash in order to shift the loads on the car seat.\nFor the last 40 years, vehicle safety researchers have been designing and gathering information on the ability of head restraints to mitigate injuries resulting from rear-end collisions. As a result, different types of head restraints have been developed by various manufacturers to protect their occupants from whiplash. \nBelow are definitions of different types of head restraints. \nHead restraint — refers to a device designed to limit the rearward displacement of an adult occupant's head in relation to the torso in order to reduce the risk of injury to the cervical vertebrae in the event of a rear impact. The most effective head restraint must allow a backset motion of less than 60 mm to prevent the hyperextension of the neck during impact.\nIntegrated head restraint or fixed head restraint — refers to a head restraint formed by the upper part of the seat back, or a head restraint that is not height adjustable and cannot be detached from the seat or the vehicle structure except by the use of tools or following the partial or total removal of the seat furnishing”. \nAdjustable head restraint — refers to a head restraint that is capable of being positioned to fit the morphology of the seated occupant. The device may permit horizontal displacement, known as tilt adjustment, and/or vertical displacement, known as height adjustment. \nActive head restraint — refers to a device designed to automatically improve head restraint position and/or geometry during an impact. \nAutomatically adjusting head restraint — refers to a head restraint that automatically adjusts the position of the head restraint when the seat position is adjusted. \nA major issue in whiplash prevention is the lack of proper adjustment of the seat safety system by both drivers and passengers. Studies have shown that a well designed and adjusted head restraint could prevent potentially injurious head-neck kinematics in rear-end collisions by limiting the differential movement of the head and torso. The primary function of a head restraint is to minimize the relative rearward movement of the head and neck during rear impact. During a rear-end collision, the presence of an effective head restraint behind the occupant's head can limit the differential movement of the head and torso. A properly placed head restraint where one can sufficiently protect one's head lower the chances of neck injury by up to 43% during a rear-end collision.\nIn contrast to a properly adjusted head restraint, research suggests that there may be an increased risk of neck injuries if the head restraint is incorrectly positioned. More studies by manufacturers and automobile safety organizations are currently undergoing to examine the best ways to reduce head and torso injuries during a rear-end impact with different geometries of the head restraint and seat-back systems. \nIn most passenger vehicles where manually adjustable head restraints are fitted, proper use requires sufficient knowledge and awareness by occupants. When driving, the height of the head restraint is critical in influencing injury risk. A restraint should be at least as high as the head's center of gravity, or about 9 centimeters (3.5 inches) below the top of the head. The backset, or distance behind the head, should be as small as possible. Backsets of more than 10 centimeters (about 4 inches) have been associated with increased symptoms of neck injury in crashes.\nDue to low public awareness of the consequence of incorrect positioning of head restraints, some passenger vehicle manufactures have designed and implemented a range of devices into their models to protect their occupants.\nSome current systems are:\nThe Insurance Institute for Highway Safety (IIHS) and other testing centers around the world have been involved in testing the effectiveness of head restraint and seat systems in laboratory conditions to assess their ability to prevent or mitigate whiplash injuries. They have found that over 60% of new motor vehicles on the market have “good” rated head restraints.", "Engineering,_Manufacturing": 0.9967170358, "qwen": "Yes"}
{"id": "6249673", "revid": "1135715500", "url": "https://en.wikipedia.org/wiki?curid=6249673", "title": "Jig grinder", "text": "A jig grinder is a machine tool used for grinding complex shapes and holes where the highest degrees of accuracy and finish are required.\nThe jig grinder is very similar to a jig borer, in that the table positioning and spindles are very accurate (far more so than a manual milling machine or lathe). It is almost exclusively used by tool and die makers in the creation of jigs or mating holes and pegs on dies. There are usually many peripheral elements to a large jig grinder, including separate hydraulic motors, air compressors, and various cooling systems for both the hydraulic circuit and supplying coolant to the work and machine itself.\nThe machine operates by a high speed air spindle rotating a grinding bit. The air spindles are removable and interchangeable to achieve varying surface speeds. Some spindles are fixed speed (60,000 rpm), others are adjustable (30,000-50,000 rpm), and still others are very high speed (175,000 rpm). The machines have a standard X-Y table with the notable exception of knee travel. All axes are indexed to 0.0001\" via a vernier scale on the handwheels, with higher accuracy available with the use of measuring bars. The machine head has two vertical travels, one rough head adjustment and the other a precise spindle adjustment. To change the diameter of the hole to be ground the air spindle can be offset from the axis of the rotary head by a slide in a similar manner to a boring head for a milling machine, allowing a hole of any size to be ground with the same tooling (up to the machine's capacity). This offset can be adjusted while running and can typically outfeed about 0.100\", again with an accuracy of 0.0001\" on the handwheel or greater, for very precise hole, peg and surface grinding. A well-kept jig grinder will reliably position work to a higher degree of accuracy than is possible with handwheels alone. These features are all critical in positioning a hole and peg system a precise distance from a reference surface or edge.\nThe most important factor on a jig grinder is the dual-spindle configuration. The main spindle is roughly positioned with between 1\" or 2\" of travel for setup, and then the 0.100\" of outfeed is used during machine operation to outfeed into the work. A spacer bar may be used between the grinder and main spindle, allowing large (9\" radius or larger) work to be completed. The main spindle has a wide range of speeds to ensure proper grinder feed rates are maintained.\nOn October 19, 2022, the United States Department of Justice charged four individuals and two companies with violating U.S. export laws by attempting to smuggle a jig grinder, which is a dual use, export-controlled item, to Russia.", "Engineering,_Manufacturing": 1.0000046492, "qwen": "Yes"}
{"id": "6251874", "revid": "7034620", "url": "https://en.wikipedia.org/wiki?curid=6251874", "title": "Gear cutting", "text": "Gear cutting is any machining process for creating a gear. The most common gear-cutting processes include hobbing, broaching, milling, grinding, and skiving. Such cutting operations may occur either after or instead of forming processes such as forging, extruding, investment casting, or sand casting.\nGears are commonly made from metal, plastic, and wood. Although gear cutting is a substantial industry, many metal and plastic gears are made without cutting, by processes such as die casting or injection molding. Some metal gears made with powder metallurgy require subsequent machining, whereas others are complete after sintering. Likewise, metal or plastic gears made with additive manufacturing may or may not require finishing by cutting, depending on application.\nProcesses.\nBroaching.\nFor very large gears or spline, a vertical broach is used. It consists of a vertical rail that carries a single tooth cutter formed to create the tooth shape. A rotary table and a Y axis are the customary axes available. Some machines will cut to a depth on the Y axis and index the rotary table automatically. The largest gears are produced on these machines.\nOther operations such as broaching work particularly well for cutting teeth on the inside. The downside to this is that it is expensive and different broach sticks are required to make different sized gears. Therefore, it is mostly used in very high production runs.\nHobbing.\nHobbing is a method by which a \"hob\" is used to cut teeth into a blank. We gear hobbing with a master hob or index hob on CNC gear hobbing machines who cut, gears, wheels, pinions, shafts and worms. The cutter and gear blank are rotated at the same time to transfer the profile of the hob onto the gear blank. Used very often for all sizes of production runs, but works best for medium to high. The hobbing features for gears are straight, helical, straight bevel, face, crowned, worm, cylkro and chamfering.\nMilling or grinding.\nSpur may be cut or ground on a milling machine or jig grinder utilizing a numbered gear cutter, and any indexing head or rotary table. The number of the gear cutter is determined by the tooth count of the gear to be cut.\nTo machine a helical gear on a manual machine, a true indexing fixture must be used. Indexing fixtures can disengage the drive worm, and be attached via an external gear train to the machine table's handle (like a power feed). It then operates similarly to a carriage on a lathe. As the table moves on the X axis, the fixture will rotate in a fixed ratio with the table. The indexing fixture itself receives its name from the original purpose of the tool: moving the table in precise, fixed increments. If the indexing worm is not disengaged from the table, one can move the table in a highly controlled fashion via the indexing plate to produce linear movement of great precision (such as a vernier scale).\nThere are a few different types of cutters used when creating gears. One is a rack shaper. These are straight and move in a direction tangent to the gear, while the gear. They have six to twelve teeth and eventually have to be moved back to the starting point to begin another cut.\nShaping.\nThe old method of gear cutting is mounting a gear blank in a shaper and using a tool shaped in the profile of the tooth to be cut. This method also works for cutting internal splines.\nAnother is a pinion-shaped cutter that is used in a gear shaper machine. It is basically when a cutter that looks similar to a gear cuts a gear blank. The cutter and the blank must have a rotating axis parallel to each other. This process works well for low and high production runs.\nFinishing.\nAfter being cut the gear can be finished by shaving, burnishing, grinding, honing or lapping.\nFurther reading.\nA guide to cutting; by Zuber Beekhory", "Engineering,_Manufacturing": 0.9999629259, "qwen": "Yes"}
{"id": "44211647", "revid": "1149259121", "url": "https://en.wikipedia.org/wiki?curid=44211647", "title": "Glass-filled polymer", "text": "Glass-filled polymer (or glass-filled plastic), is a mouldable composite material. It comprises short glass fibers in a matrix of a polymer material. It is used to manufacture a wide range of structural components by injection or compression moulding. It is an ideal glass alternative that offers flexibility in the part, chemical resistance, shatter resistance and overall better durability.\nMaterials.\nEither thermoplastic or thermosetting polymers may be used. One of the most widely used thermoplastics is a polyamide polymer nylon.\nThe first mouldable composite was Bakelite. This used wood flour fibres in phenolic resin as the thermoset polymer matrix. As the fibres were only short this material had relatively low bulk strength, but still improved surface hardness and good mouldability. \nA wide range of polymers are now produced in glass-filled varieties, including polyamide (Nylon), acetal homopolymers and copolymers, polyester, polyphenylene oxide (PPO / Noryl), polycarbonate, polyethersulphone\nBulk moulding compound is a pre-mixed material of resin and fibres supplied for moulding. Some are thermoplastic or thermosetting, others are chemically cured and are mixed with a catalyst (polyester) or hardener (epoxy) before moulding.\nApplications.\nCompared to the native polymer, glass-filled materials have improved mechanical properties of rigidity, strength and may also have improved surface hardness.\nCompared to sheet materials.\nBulk glass \"filled\" materials are considered distinct from fibreglass or fibre-reinforced plastic materials. These use a substrate of fabric sheets made from long fibres, draped to shape in a mould and then impregnated with resin. They are usually moulded into shapes made of large but thin sheets. Filled materials, in contrast, are used for applications that are thicker or of varying section and not usually as large as sheet materials.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "44215035", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=44215035", "title": "Fused filament fabrication", "text": "Fused filament fabrication (FFF), also known as fused deposition modeling (with the trademarked acronym FDM), or \"filament freeform fabrication\", is a 3D printing process that uses a continuous filament of a thermoplastic material. Filament is fed from a large spool through a moving, heated printer extruder head, and is deposited on the growing work. The print head is moved under computer control to define the printed shape. Usually the head moves in two dimensions to deposit one horizontal plane, or layer, at a time; the work or the print head is then moved vertically by a small amount to begin a new layer. The speed of the extruder head may also be controlled to stop and start deposition and form an interrupted plane without stringing or dribbling between sections. \"Fused filament fabrication\" was coined by the members of the RepRap project to give an acronym (FFF) that would be legally unconstrained in its use.\nFused filament printing is now the most popular process (by number of machines) for hobbyist-grade 3D printing. Other techniques such as photopolymerisation and powder sintering may offer better results, but they are much more costly.\nThe 3D printer head or 3D printer extruder is a part in material extrusion additive manufacturing responsible for raw material melting or softening and forming it into a continuous profile. A wide variety of filament materials are extruded, including thermoplastics such as \"acrylonitrile butadiene styrene\" (ABS), \"polylactic acid\" (PLA), \"polyethylene terephthalate glycol\" (PETG), \"polyethylene terephthalate\" (PET), high-impact \"polystyrene\" (HIPS), \"thermoplastic polyurethane\" (TPU) and \"aliphatic polyamides\" (nylon).\nHistory.\nFused deposition modeling was developed by S. Scott Crump, co-founder of Stratasys, in 1988. With the 2009 expiration of the patent on this technology, people could use this type of printing without paying Stratasys for the right to do so, opening up commercial, DIY, and open-source (RepRap) 3D printer applications. This has led to a two-orders-of-magnitude price drop since this technology's creation. Stratasys still owns the trademark on the term \"FDM\".\nProcess.\n3D printing, also referred to as additive manufacturing (AM), involves manufacturing a part by depositing material layer by layer. There is a wide array of different AM technologies that can do this, including material extrusion, binder jetting, material jetting and directed energy deposition. These processes have varied types of extruders and extrude different materials to achieve the final product.\nMaterial extrusion.\nFused filament fabrication uses material extrusion to print items, where a feedstock material is pushed through an extruder. In most fused filament fabrication 3D printing machines, the feedstock material comes in the form of a filament wound onto a spool.\nThe 3D printer liquefier is the component predominantly used in this type of printing. Extruders for these printers have a cold end and a hot end. The cold end pulls material from the spool, using gear- or roller-based torque to the material and controlling the feed rate by means of a stepper motor. The cold end pushes feedstock into the hot end. The hot end consists of a heating chamber and a nozzle. The heating chamber hosts the liquefier, which melts the feedstock to transform it into a liquid. It allows the molten material to exit from the small nozzle to form a thin, tacky bead of plastic that will adhere to the material it is laid on. The nozzle will usually have a diameter of between 0.3 mm and 1.0 mm. Different types of nozzles and heating methods are used depending upon the material to be printed.\nDifferent types of nozzles have different ways of replacing them. The most common used nozzles are the V6 nozzles made popular by E3D and MK8 nozzles. Changing the nozzle must be done while hot, to avoid plastic leaks.\nPrinting.\nFFF begins with a software process which processes an STL file (Standard Triangle Language), orienting the model for the build process and mathematically slicing the model according to the processing parameters selected. If required, support structures may be generated. \nThe nozzle can be moved in both horizontal and vertical directions, and is mounted to a mechanical stage, which can be moved in the xy plane.\nAs the nozzle is moved over the table in a prescribed geometry, it deposits a thin bead of extruded plastic, called a ‘‘road’’ which solidifies quickly upon contact with the substrate and/or roads deposited earlier. Solid layers are generated by following a rasterizing motion where the roads are deposited side by side within an enveloping domain boundary.\nStepper motors or servo motors are typically employed to move the extrusion head. The mechanism used is often an X-Y-Z rectilinear design, although other mechanical designs such as deltabot have been employed.\nOnce a layer is completed, the platform is lowered in the z direction in order to start the next layer. This process continues until the fabrication of the object is completed.\nFor successful bonding of the roads in the process, thermal control of the deposited material is necessary. The system can be kept inside a chamber, maintained at a temperature below the melting point of the material being deposited.\nAlthough as a printing technology FFF is very flexible, and it is capable of dealing with small overhangs by the support from lower layers, FFF generally has some restrictions on the slope of the overhang, and cannot produce unsupported stalactites.\nMyriad materials are available, such as Acrylonitrile Butadiene Styrene (ABS), Polylactic acid (PLA), Polycarbonate (PC), Polyamide (PA), Polystyrene (PS), lignin, rubber, among many others, with different trade-offs between strength and temperature properties. In addition, even the color of a given thermoplastic material may affect the strength of the printed object. Recently a German company demonstrated for the first time the technical possibility of processing granular PEEK into filament form and 3D printing parts from the filament material using FFF technology.\nDuring FFF, the hot molten polymer is exposed to air. Operating the FFF process within an inert gas atmosphere such as nitrogen or argon can significantly increase the layer adhesion and leads to improved mechanical properties of the 3D printed objects. An inert gas is routinely used to prevent oxidation during selective laser sintering.\nPhysics of the process.\nDuring extrusion the thermoplastic filament is introduced by mechanical pressure from rollers, into the liquefier, where it melts and is then extruded. Flow geometry of the extruder, heating method and the melt flow behavior of a non-Newtonian fluid are of main consideration in the part. The rollers are the only drive mechanism in the material delivery system, therefore filament is under tensile stress upstream to the roller and under compression at the downstream side acting as a plunger. Therefore, compressive stress is the driving force behind the extrusion process.\nThe force required to extrude the melt must be sufficient to overcome the pressure drop across the system, which strictly depends on the viscous properties of the melted material and the flow geometry of the liquefier and nozzle. The melted material is subjected to shear deformation during the flow. Shear thinning behavior is observed in most of the materials used in this type of 3-D printing. This is modeled using power law for generalized Newtonian fluids.\nThe temperature is regulated by heat input from electrical coil heaters. The system continuously adjusts the power supplied to the coils according to the temperature difference between the desired value and the value detected by the thermocouple, forming a negative feedback loop. This is similar to ambient heating of a room.\nApplications.\nCommercial applications.\nFFF and the other technologies of additive manufacturing by material extrusion (EAM) techniques are commonly used for prototyping and rapid manufacturing. Rapid prototyping facilitates iterative testing, and for very short runs, rapid manufacturing can be a relatively inexpensive alternative. EAM is also used in prototyping scaffolds for medical tissue engineering applications. Moreover, EAM with multi extrusion have become very popular to fabricate biomimetic composites. FFF is also applied in manufacturing within other sectors, including aerospace, automotive, construction, electronics, energy, pharmaceuticals, sports,\ntextiles, and toys.\nFree applications.\nThere are multiple projects in the open-sourced community aimed at processing post-consumer plastic waste into filament. These involve machines used to shred and extrude the plastic material into filament such as recyclebots.\nSeveral projects and companies are making efforts to develop affordable 3D printers for home desktop use. Much of this work has been driven by and targeted at DIY/enthusiast/early adopter communities, with additional ties to the academic and hacker communities.\nRepRap is one of the longest running projects in the desktop category. The RepRap project aims to produce a free and open source hardware (FOSH) 3D printer, whose full specifications are released under the GNU General Public License, and which is capable of replicating itself by printing many of its own (plastic) parts to create more machines. RepRaps have already been shown to be able to print circuit boards and metal parts. Fab@Home is the other opensource hardware project for DIY 3D printers.\nBecause of the FOSH aims of RepRap, many related projects have used their design for inspiration, creating an ecosystem of related or derivative 3D printers, most of which are also open source designs. The availability of these open source designs means that variants of 3D printers are easy to invent. The quality and complexity of printer designs, however, as well as the quality of kit or finished products, varies greatly from project to project. This rapid development of open source 3D printers is gaining interest in many spheres as it enables hyper-customization and the use of public domain designs to fabricate open source appropriate technology. This technology can also assist initiatives in sustainable development since technologies are easily and economically made from resources available to local communities.\nDevelopment.\nCustomer-driven product customization and demand for cost and time savings have increased interest in agility of manufacturing process. This has led to improvements in rapid prototyping technologies. The development of extruders is going rapidly because of the open source 3-D printer movement caused by products like RepRap. E3D and BondTech are the most known extruder manufacturers currently on the market. Consistent improvements are seen in the form of increased heating temperature of liquefiers, better control and precision of prints, and improved support for a wide variety of materials. Besides the improved hardware, the ability to calibrate the extruder according to the hardware setup has come a long way.\nCost of 3D printer.\nThe cost of 3D printers has decreased dramatically since about 2010, with machines that used to cost now costing less than . For instance, as of 2017, several companies and individuals are selling parts to build various RepRap designs, with prices starting at about / .\nThe open source Fab@Home project has developed printers for general use with anything that can be extruded through a nozzle, from chocolate to silicone sealant and chemical reactants. Printers following the project's designs have been available from suppliers in kits or in pre-assembled form since 2012 at prices in the range.\nThe LulzBot 3D printers manufactured by Aleph Objects are another example of an open-source application of fused deposition modeling technology. The flagship model in the LulzBot line, the TAZ printer takes inspiration for its design from the RepRap Mendel90 and Prusa i3 models. The LulzBot 3D printer is currently the only printer on the market to have received the \"Respects Your Freedom\" certification from the Free Software Foundation.\nAs of September 2018 RepRap style printers are readily available in kit form through online retailers. These kits come complete with all parts needed to make a functioning printer, often including electronic files for test printing as well as a small quantity of PLA filament.\nFilaments used for printing with FDM printers are also substantially more cost-effective than their SLA resin counterparts. If we use 3DBenchy as a benchmark for comparing both technologies, it would cost roughly $0.20 to print such a model with an FDM machine, whereas the same object would cost almost $1.00 if created with resin.\nMaterials.\nPlastic is the most common material for 3d printing via FFF and other EAM variants. Various polymers may be used, including acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polylactic acid (PLA), high-density polyethylene (HDPE), PC/ABS, polyethylene terephthalate (PETG), polyphenylsulfone (PPSU) and high impact polystyrene (HIPS). In general, the polymer is in the form of a filament fabricated from virgin resins. Additionally, fluoropolymers such as PTFE tubing are used in the process due to the material's ability to withstand high temperatures. This ability is especially useful in transferring filaments.\nThe many different variants of EAM, i.e. of material Extrusion based Additive Manufacturing allow dealing with many additional material types, summarised in the table below. Several material classes can be extruded and 3d printed:\nPrint head kinematics.\nThe majority of fused filament printers follow the same basic design. A flat bed is used as the starting point for the print workpiece. A gantry above this carries the moving print head. The gantry design is optimized for movement mostly in the horizontal X & Y directions, with a slow climb in the Z direction as the piece is printed. Stepper motors drive the movement through either leadscrews or toothed belt drives. It is common, owing to the differences in movement speed, to use toothed belts for the X,Y drives and a leadscrew for Z. Some machines also have X axis movement on the gantry, but move the bed (and print job) for Y. As, unlike laser cutters, head movement speeds are low, stepper motors are universally used and there is no need to use servomotors instead.\nMany printers, originally those influenced by the RepRap project, make extensive use of 3D printed components in their own construction. These are typically printed connector blocks with a variety of angled holes, joined by cheap steel threaded rod. This makes a construction that is cheap and easy to assemble, easily allows non-perpendicular framing joints, but does require access to a 3D printer. The notion of 'bootstrapping' 3D printers like this has been something of a dogmatic theme within the RepRap designs. The lack of stiffness in the rod also requires either triangulation, or gives the risk of a gantry structure that flexes and vibrates in service, reducing print quality.\nMany machines now use box-like semi-enclosed frames of either laser-cut plywood, plastic, pressed steel sheet and more recently aluminum extrusions. These are cheap, rigid and can also be used as the basis for an enclosed print volume, allowing temperature control within it to control warping of the print job.\nA handful of machines use polar coordinates instead, usually machines optimized to print objects with circular symmetry. These have a radial gantry movement and a rotating bed. Although there are some potential mechanical advantages to this design for printing hollow cylinders, their different geometry and the resulting non-mainstream approach to print planning still keeps them from being popular as yet. Although it is an easy task for a robot's motion planning to convert from Cartesian to polar coordinates, gaining any advantage from this design also requires the print slicing algorithms to be aware of the rotational symmetry from the outset.\nExtruder mount to rest of machine.\nThe ways extruders are mounted on the rest of the machine have evolved over time into informal mounting standards. Such factor standards allow new extruder designs to be tested on existing printer frames, and new printer frame designs to use existing extruders. These informal standards include:\nDelta robot printers.\nA different approach is taken with 'Rostock' or 'Kossel' pattern printers, based on a delta robot mechanism. These have a large open print volume with a three-armed delta robot mounted at the top. This design of robot is noted for its low inertia and ability for fast movement over a large volume. Stability and freedom from vibration when moving a heavy print head on the end of spindly arms is a technical challenge though. This design has mostly been favored as a means of gaining a large print volume without a large and heavy gantry.\nAs the print head moves the distance of its filament from storage coil to head also changes, the tension created on the filament is another technical challenge to overcome to avoid affecting the print quality.", "Engineering,_Manufacturing": 1.0000082254, "qwen": "Yes"}
{"id": "54409102", "revid": "41315924", "url": "https://en.wikipedia.org/wiki?curid=54409102", "title": "Model-based enterprise", "text": "Model-based enterprise (MBE) is a term used in manufacturing, to describe a strategy where an annotated digital three-dimensional (3D) model of a product serves as the authoritative information source for all activities in that product's lifecycle.\nA key advantage of MBE is that it replaces digital drawings. In MBE, a single 3D model contains all the information typically found on in an entire set of engineering drawings, including geometry, topology, dimensions, tolerances, materials, finishes, and weld call-outs.\nMBE was originally championed by the aerospace and defense industries, with the automotive industry following. It has been adopted by many manufacturers around the world, in a wide range of industries. Significant benefits for manufacturers include reduced time to market and savings in production costs from improved tool design and fabrication, fewer overall assembly hours, less rework, streamlined development and better collaboration on engineering changes.\nThere are two prerequisites to implementing MBE: The first is the creation of annotated 3D models, known as a Model-based definitions (MBD). This requires the use of a CAD system capable of creating precise solid models, with product and manufacturing information (PMI), a form of 3D annotation which may include dimensions, GD&T, notes, surface finish, and material specifications. (The mechanical CAD systems used in aerospace, defense, and automotive industries generally have these capabilities.) The second prerequisite is transforming MBDs into a form where they can be used in downstream lifecycle activities. As a rule, CAD models are stored in proprietary data formats, so they must be translated to a suitable MBD-compatible standard format, such as 3D PDF, JT, STEP AP 242, or ANSI QIF\nThe core MBE tenet is that models are used to drive all aspects of the product lifecycle and that data is created once and reused by all downstream data consumers. Data reusability requires computer interpretability, where an MBD can be processed directly by downstream applications, and associativity of PMI to specific model features within the MBD.\nHistory.\nHistorically, engineering and manufacturing activities have relied on hardcopy and/or digital documents (including 2D drawings) to convey engineering data and drive manufacturing processes. These documents required interpretation by skilled practitioners, often leading to ambiguities and errors.\nIn the 1980s, improvements in 3D solid modeling made it possible for CAD systems to precisely represent the shape of most manufactured goods—however, even enthusiastic adopters of solid modeling technology continued to rely upon 2D drawings (often CAD generated) as the authority (or master) product representation. 3D models, even if geometrically accurate, lacked a method to represent dimensions, tolerances, and other annotative information required to drive manufacturing processes.\nIn the early-to-middle 2000s, the ASME Y14.41-2003 Digital Product Data Definition Practices and ISO 16792:2006 Technical product documentation—Digital product definition data practices standards were released, providing support for PMI annotations in 3D CAD models, and introducing the concept of MBD (or, alternatively, digital product definition)\nThe model-based enterprise concept first appeared about 2005. Initially it was construed broadly, referring to the pervasive use of modeling and simulation technologies (of almost any type) throughout an enterprise. In the late 2000s, An active community advocating development of MBE grew, based on the collaborative efforts of the Office of the Secretary of Defense, Army Research Laboratory, Armament Research Development Engineering Center (ARDEC), Army ManTech, BAE Systems, NIST, and the NIST Manufacturing Extension Partnership (MEP). The \"MBE Team\" included industry participants such as General Dynamics, Pratt & Whitney Rocketdyne, Elysium, Adobe, EOS, ITI TranscenData, Vistagy, PTC, Dassault Systemes Delmia, Boeing, and BAE Systems.\nOver time, based on community feedback, MBE became more narrowly construed, referring to the use of MBD data to drive product lifecycle activities. In 2011, the MBE Team published these definitions:\nBy 2015, with improvements to ASME Y14.41 and ISO 16792, and the development of open CAD data exchange standards capable of adequately representing PMI, MBE started to become more widely adopted by manufacturers.", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "4019197", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=4019197", "title": "Wiring pencil", "text": "A wiring pencil (often sold under the trade names of Roadrunner or Verowire) is a tool for making electrical connections.\nA small reel of insulated copper wire is mounted at the top of the tool. The wire runs down the center of the wiring pencil and through a hardened tip, which is small enough to move between the pins of 0.1\" pitch DIL chip allowing connections to be wrapped and the wire to be led across the circuit board to the next point it's needed.\nThe wire is coated with a polymer lacquer (commonly referred to as enamel, but not glass based). Once wrapped the connections are soldered, the heat of this burning the lacquer away and completing the joint. Insulated wire is normally 38 SWG (0.15mm), ground connections are sometimes made with uninsulated wire which is slightly heavier (33 SWG, 0.25mm).\nA well ventilated area and/or fume extraction are very important when carrying out this process due to the toxic fumes. Sometimes, where there are many wires, plastic comb-like structures are used for wire management.", "Engineering,_Manufacturing": 0.9612555504, "qwen": "Yes"}
{"id": "4025575", "revid": "1012244938", "url": "https://en.wikipedia.org/wiki?curid=4025575", "title": "Sendzimir process", "text": "Sendzimir process (named after Tadeusz Sendzimir) is used to galvanize a steel strip by using a small amount of aluminum in the zinc bath and producing a coating with essentially no iron-zinc alloy. The process guarantees high resistance and durability characteristics. About 75% of hydrogen was needed in the original Sendzimir process but all the newer nonoxidizing methods of degreasing require only 7–15%. \nThe rolling of hot steel slabs using a Sendzimir mill requires a much smaller operational area than a continuous hot strip mill.\nThis milling process is not recommended for heavy duty running surfaces such as crane rail.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "1011484", "revid": "46100349", "url": "https://en.wikipedia.org/wiki?curid=1011484", "title": "Seiko Instruments", "text": " (SII) is a Japanese company, which develops and commercializes semiconductor, micromechatronics, and precision machining technologies. It is one of business units of Seiko Group Corporation (f/k/a Seiko Holdings).\nHeadquartered in the Makuhari business district, Mihama-ku, Chiba City, Chiba Prefecture, Japan, the company manufactures and sells electronic components (crystal oscillators, micromechatronics devices, piezo inkjet printheads, microbatteries, supercapacitors), precision parts, analysis and measurement instruments, machine tools, factory automation systems, printers, etc.\nIn 1937 , literally the second workshop for manufacturing Seiko timepieces, was established in Kamedo, Kōtō, Tokyo as a spin-off of the watch manufacturing division from , so had been making the Seiko watches until 2020. The company changed its name to Seiko Instruments & Electronics Ltd. in 1983 and to the current name in 1997. Its Suwa Plant in Suwa, Nagano Prefecture spun off as in 1959 is now known as .\nOn January 26, 2009, Seiko Instruments and Seiko Holdings announced that the two companies will be merged on October 1, 2009 through a share swap. Seiko Instruments became a wholly owned subsidiary of Seiko Holdings on the date that had been announced before.\nSeiko had delegated a large portion of the manufacturing in its watch business to SII. Watches manufactured by SII were sold through the Seiko Watch Corporation, a subsidiary of Seiko Holdings Corporation. On April 1, 2020, the company transferred its watch business including its watch manufacturing subsidiaries Morioka Seiko Instruments, Ninohe Tokei Kogyo, Seiko Instruments Singapore, etc. to Seiko Watch.", "Engineering,_Manufacturing": 0.9990782142, "qwen": "Yes"}
{"id": "22228980", "revid": "37946496", "url": "https://en.wikipedia.org/wiki?curid=22228980", "title": "Believe Pictures", "text": "Believe Pictures is a production company founded by partners Brian Bird, and Michael Landon, Jr. They have created (or co-created) major films such as \"The Last Sin Eater\", the \"Love Comes Softly\" film series and Saving Sarah Cain, which won a 2008 CAMIE Award.\nMost of the releases went to Fox Faith for home video distribution.", "Engineering,_Manufacturing": 0.9998646975, "qwen": "Yes"}
{"id": "22250500", "revid": "1150845048", "url": "https://en.wikipedia.org/wiki?curid=22250500", "title": "Request for waiver", "text": "In a manufacturing environment, a request for waiver (RFW) is a request for authorization to accept an item which, during manufacture or after inspection, is found to depart from specified requirements, but nevertheless is considered suitable for use \"as is\" or after repair by an approved method.\nIn ECSS standard a RFW is defined as \"unplanned  departure\", as opposite to Request for Deviation (RFD) which is defined as \"planned departure\", being \"departure\" defined as the \"inability of a product to  meet one of its functional performance or technical requirements\". In both cases, no changes are applied to engineering documentation.\nIn accordance with MIL-HDBK-61A, the term \"waiver\" is no longer used, because the processing rules for a RFW are identical to those for a deviation, and the terms deviation and waiver were often confused.\nA deviation from the contractual performance requirements or approved drawings should be submitted as a RFD. An RFD is a specific written authorization to depart from a particular requirement of an item's approved configuration documentation for a specific number of units or period of time. A deviation does not change configuration documentation.\nDeviations are requested by contractors prior to manufacture, during manufacture, or after an item has been submitted for Customer inspection and acceptance. To be tendered for delivery or to be installed in an item to be tendered for delivery, deviant items must be suitable for use.", "Engineering,_Manufacturing": 0.9975712299, "qwen": "Yes"}
{"id": "23980156", "revid": "21417351", "url": "https://en.wikipedia.org/wiki?curid=23980156", "title": "Servo Robot Group", "text": "SERVO-ROBOT Group is a company that develops and creates intelligent sensing and digital vision systems to simplify manufacturing process automation such as welding. Therefore, the main activity is to build intelligent sensing systems based on precision measurement with laser beams and other intelligent sensing devices applicable to various industries such as automotive, railroad, pipe and tube, aerospace, shipbuilding, fabricated structures, windmill towers manufacturing, etc.\nFounded in 1983, SERVO-ROBOT has established its world headquarters, production plant and research and development center in the St-Bruno Industrial Park, south of Montreal, Quebec, Canada. More than 95% of SERVO-ROBOT's products are exported outside of Canada every year.\nApplications.\nInnovations developed in patents mentioned in the above section resulted in concrete solutions easily applicable to markets ranging from automotive to aerospace which has helped many companies and factories to become more productive and reach their Six Sigma constant improvements goals.\nExternal links.\nRobotic Industry Association \nManufacturing Talk ", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "23984989", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=23984989", "title": "Energy Manufacturing Co. Inc", "text": "Energy Manufacturing Co., Inc. is an American manufacturing company based in Monticello, Iowa. Established in 1944, the company produces a variety of hydraulic cylinders, hydraulic pumps, valves, and power systems.\nHistory.\nIn the early 1940s B.J. Pasker ran a blacksmith shop in New Vienna, Iowa. In this shop his son, Jerry, produced farm wagons made from discarded automobile spindles and rims. During this period, Pasker also developed a hydraulically powered front loader which mounted to farm tractors. In 1944 Jerry Pasker outgrew the blacksmith shop and sought a larger facility for his operations.\nEnergy in Monticello Iowa.\nJerry Pasker moved to South Cedar Street in Monticello, Iowa and was introduced to Harold Sovereign, who sold John Deere tractors and equipment. Pasker and Sovereign formed a partnership known as Industrious Farmer Equipment Company, and moved the business to the vacant second floor of Sovereign's dealership on South Cedar Street. In 1946 the business again outgrew its facility. To accommodate the expansion, Pasker purchased the property of an auto dealership on Main Street. During that time the company manufactured hydraulic components, wagon hoists, truck hoists, valves and hydraulic cylinders. In 1948 the company's name was changed to Energy Farm Equipment Company. In 1962 the business incorporated to become Energy Manufacturing Company, Inc., by which it is still known.\nJerry Pasker was killed in a 22 July 1964 airplane crash in Winnipeg, Manitoba, Canada; the company presidency then passed to LaVon Pasker.\nEnergy Manufacturing after Jerry Pasker.\nIn 1976 Energy completed construction of a new plant on in the Monticello Industrial park. In 1985 Energy Manufacturing Company was sold to CGF Industries of Topeka, Kansas. CGF also purchased an Omaha Nebraska company called \"Williams Machine and Tool\". In 1997 Energy was purchased by Lincolnshire Partners and in 1999 Energy was purchased by Textron, Inc. Textron ran the company for 5 years until Energy was acquired by an investment group. On November 15, 2005 Energy added to the facility office space for administrative and manufacturing support.\nEnergy 2005 - 2013.\nEnergy designs and manufactures custom welded hydraulic cylinders. It also designs and manufactures hydraulic valves, pumps, powerpacks and power systems. Energy's cylinders are used in construction, road machinery, forestry, man lift and hoist, industrial bailer, waste compacting, and agricultural industries. Energy manufactures a wide variety of hydraulic cylinders; welded, tie-rod, ram-type, rephasing, telescopic, and position-sensing. Energy has designed and manufactured hydraulic cylinders with bores from less than one inch (2.5 cm), up to 11 inches (28 cm). Cylinders have been manufactured with strokes up to 15 feet (4.5 cm). Energy has designed cylinders with working pressures as high as 10,000 psig (690 bar).\nEnergy Manufacturing sold.\nOn May 30, 2013 Ligon Industries LLC acquired Energy Manufacturing Co. Inc.. Ligon Industries, LLC was founded in 1999, and is located in Birmingham, Alabama. In addition to Energy Manufacturing, Ligon holds 13 other manufacturing companies, seven of which are in the fluid power industry. Ligon is the largest independent manufacturer of hydraulic cylinders in North America.", "Engineering,_Manufacturing": 0.9973557591, "qwen": "Yes"}
{"id": "1993994", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=1993994", "title": "Operations management", "text": "Operations management is an area of management concerned with designing and controlling the process of production and redesigning business operations in the production of goods or services. It involves the responsibility of ensuring that business operations are efficient in terms of using as few resources as needed and effective in meeting customer requirements. \nIt is concerned with managing an entire production or service system which is the process that converts inputs (in the forms of raw materials, labor, consumers, and energy) into outputs (in the form of goods and/or services for consumers). Operations produce products, manage quality and create services. Operation management covers sectors like banking systems, hospitals, companies, working with suppliers, customers, and using technology. Operations is one of the major functions in an organization along with supply chains, marketing, finance and human resources. The operations function requires management of both the strategic and day-to-day production of goods and services.\nIn managing manufacturing or service operations several types of decisions are made including operations strategy, product design, process design, quality management, capacity, facilities planning, production planning and inventory control. Each of these requires an ability to analyze the current situation and find better solutions to improve the effectiveness and efficiency of manufacturing or service operations. A modern, integrated vision of the many aspects of operations management may be found in recent textbooks on the subject.\nHistory.\nThe history of production and operation systems begins around 5000 B.C. when Sumerian priests developed the ancient system of recording inventories, loans, taxes, and business transactions. The next major historical application of operation systems occurred in 4000 B.C. It was during this time that the Egyptians started using planning, organization, and control in large projects such as the construction of the pyramids. By 1100 B.C., labor was being specialized in China; by about 370 B.C., Xenophon described the advantages of dividing the various operations necessary for the production of shoes among different individuals in ancient Greece:\nIn the Middle Ages, kings and queens ruled over large areas of land. Loyal noblemen maintained large sections of the monarch's territory. This hierarchical organization in which people were divided into classes based on social position and wealth became known as the feudal system. In the feudal system, vassals and serfs produced for themselves and people of higher classes by using the ruler's land and resources. Although a large part of labor was employed in agriculture, artisans contributed to economic output and formed guilds. The guild system, operating mainly between 1100 and 1500, consisted of two types: merchant guilds, who bought and sold goods, and craft guilds, which made goods. Although guilds were regulated as to the quality of work performed, the resulting system was rather rigid, shoemakers, for example, were prohibited from tanning hides.\nServices were also performed in the Middle Ages by servants. They provided service to the nobility in the form of cooking, cleaning and providing entertainment. Court jesters were considered service providers. The medieval army could also be considered a service since they defended the nobility.\nThe industrial revolution was facilitated by two elements: interchangeability of parts and division of labor. Division of labor has been a feature from the beginning of civilization, the extent to which the division is carried out varied considerably depending on period and location. Compared to the Middle Ages, the Renaissance and the Age of Discovery were characterized by a greater specialization in labor, which was a characteristic of the growing cities and trade networks of Europe. An important leap in manufacturing efficiency came in the late eighteenth century as Eli Whitney popularized the concept of interchangeability of parts when he manufactured 10,000 muskets. Up to this point in the history of manufacturing, each product (e.g. each musket) was considered a special order, meaning that parts of a given musket were fitted only for that particular musket and could not be used in other muskets. Interchangeability of parts allowed the mass production of parts independent of the final products in which they would be used. An entire new market to fill the need for the sale and manufacturing of muskets began at this time. \nIn 1883, Frederick Winslow Taylor introduced the stopwatch method for accurately measuring the time to perform each single task of a complicated job. He developed the scientific study of productivity and identifying how to coordinate different tasks to eliminate wasting of time and increase the quality of work. The next generation of scientific study occurred with the development of work sampling and predetermined motion time systems (PMTS). Work sampling is used to measure the random variable associated with the time of each task. PMTS allows the use of standard predetermined tables of the smallest body movements (e.g. turning the left wrist by 90°), and integrating them to predict the time needed to perform a simple task. PMTS has gained substantial importance due to the fact that it can predict work measurements without observing the actual work. The foundation of PMTS was laid out by the research and development of Frank B. and Lillian M. Gilbreth around 1912. The Gilbreths took advantage of taking motion pictures at known time intervals while operators were performing the given task.\nService Industries: At the turn of the twentieth century, the services industries were already developed, but largely fragmented. In 1900 the U.S. service industry consisted of banks, professional services, schools, general stores, railroads and telegraph. Services were largely local in nature (except for railroads and telegraph) and owned by entrepreneurs and families. The U.S. in 1900 had 31% employment in services, 31% in manufacturing and 38% in agriculture.\nThe idea of the production line has been used multiple times in history prior to Henry Ford: the Venetian Arsenal (1104); Smith's pin manufacturing, in the Wealth of Nations (1776) or Brunel's Portsmouth Block Mills (1802). Ransom Olds was the first to manufacture cars using the assembly line system, but Henry Ford developed the first auto assembly system where a car chassis was moved through the assembly line by a conveyor belt while workers added components to it until the car was completed. During World War II, the growth of computing power led to further development of efficient manufacturing methods and the use of advanced mathematical and statistical tools. This was supported by the development of academic programs in industrial and systems engineering disciplines, as well as fields of operations research and management science (as multi-disciplinary fields of problem solving). While systems engineering concentrated on the broad characteristics of the relationships between inputs and outputs of generic systems, operations researchers concentrated on solving specific and focused problems. The synergy of operations research and systems engineering allowed for the realization of solving large scale and complex problems in the modern era. Recently, the development of faster and smaller computers, intelligent systems, and the World Wide Web has opened new opportunities for operations, manufacturing, production, and service systems.\nIndustrial Revolution.\nBefore the First industrial revolution work was mainly done through two systems: domestic system and craft guilds. In the domestic system merchants took materials to homes where artisans performed the necessary work, craft guilds on the other hand were associations of artisans which passed work from one shop to another, for example: leather was tanned by a tanner, passed to curriers, and finally arrived at shoemakers and saddlers.\nThe beginning of the industrial revolution is usually associated with the eighteenth-century English textile industry, with the invention of the flying shuttle by John Kay in 1733, the spinning jenny by James Hargreaves in 1765, the water frame by Richard Arkwright in 1769 and the steam engine by James Watt in 1765. In 1851 at the Crystal Palace Exhibition the term American system of manufacturing was used to describe the new approach that was evolving in the United States of America which was based on two central features: interchangeable parts and extensive use of mechanization to produce them.\nSecond Industrial Revolution and post-industrial society.\nHenry Ford was 39 years old when he founded the Ford Motor Company in 1903, with $28,000 capital from twelve investors. The model T car was introduced in 1908, however it was not until Ford implemented the assembly line concept, that his vision of making a popular car affordable by every middle-class American citizen would be realized. The first factory in which Henry Ford used the concept of the assembly line was Highland Park (1913), he characterized the system as follows:\nThis became one of the central ideas that led to mass production, one of the main elements of the Second Industrial Revolution, along with emergence of the electrical industry and petroleum industry.\nThe post-industrial economy was noted in 1973 by Daniel Bell. He stated that the future economy would provide more GDP and employment from services than from manufacturing and have a great effect on society. Since all sectors are highly interconnected, this did not reflect less importance for manufacturing, agriculture, and mining but just a shift in the type of economic activity.\nOperations management.\nAlthough productivity benefited considerably from technological inventions and division of labor, the problem of systematic measurement of performances and the calculation of these by the use of formulas remained somewhat unexplored until Frederick Taylor, whose early work focused on developing what he called a \"differential piece-rate system\" and a series of experiments, measurements and formulas dealing with cutting metals and manual labor. The differential piece-rate system consisted in offering two different pay rates for doing a job: a higher rate for workers with high productivity (efficiency) and who produced high quality goods (effectiveness) and a lower rate for those who fail to achieve the standard. One of the problems Taylor believed could be solved with this system, was the problem of soldiering: faster workers reducing their production rate to that of the slowest worker.\nIn 1911 Taylor published his \"The Principles of Scientific Management\", in which he characterized scientific management (also known as Taylorism) as:\nTaylor is also credited for developing stopwatch time study, this combined with Frank and Lillian Gilbreth motion study gave way to time and motion study which is centered on the concepts of standard method and standard time. Frank Gilbreth is also responsible for introducing the flow process chart in 1921. Other contemporaries of Taylor worth remembering are Morris Cooke (rural electrification in the 1920s and implementer of Taylor's principles of scientific management in the Philadelphia's Department of Public Works), Carl Barth (speed-and-feed-calculating slide rules ) and Henry Gantt (Gantt chart). Also in 1910 Hugo Diemer published the first industrial engineering book: Factory Organization and Administration.\nIn 1913 Ford Whitman Harris published his \"How many parts to make at once\" in which he presented the idea of the economic order quantity model. He described the problem as follows:\nThis paper inspired a large body of mathematical literature focusing on the problem of production planning and inventory control.\nIn 1924 Walter Shewhart introduced the control chart through a technical memorandum while working at Bell Labs, central to his method was the distinction between common cause and special cause of variation. In 1931 Shewhart published his Economic Control of Quality of Manufactured Product, the first systematic treatment of the subject of Statistical Process Control (SPC). He defined control:\nIn the 1940s methods-time measurement (MTM) was developed by H.B. Maynard, J.L. Schwab and G.J. Stegemerten. MTM was the first of a series of predetermined motion time systems, predetermined in the sense that estimates of time are not determined in loco but are derived from an industry standard. This was explained by its originators in a book they published in 1948 called \"Method-Time Measurement\".\nUp to this point in history, optimization techniques were known for a very long time, from the simple methods employed by F.W.Harris to the more elaborate techniques of the calculus of variations developed by Euler in 1733 or the multipliers employed by Lagrange in 1811, and computers were slowly being developed, first as analog computers by Sir William Thomson (1872) and James Thomson (1876) moving to the electromechanical computers of Konrad Zuse (1939 and 1941). During World War II however, the development of mathematical optimization went through a major boost with the development of the Colossus computer, the first electronic digital computer that was all programmable, and the possibility to computationally solve large linear programming problems, first by Kantorovich in 1939 working for the Soviet government and latter on in 1947 with the simplex method of Dantzig. These methods are known today as belonging to the field of operations research.\nFrom this point on a curious development took place: while in the United States the possibility of applying the computer to business operations led to the development of management software architecture such as MRP and successive modifications, and ever more sophisticated optimization techniques and manufacturing simulation software, in post-war Japan a series of events at Toyota Motor led to the development of the Toyota Production System (TPS) and Lean Manufacturing.\nIn 1943, in Japan, Taiichi Ohno arrived at Toyota Motor company. Toyota evolved a unique manufacturing system centered on two complementary notions: just in time (produce only what is needed) and autonomation (automation with a human touch). Regarding JIT, Ohno was inspired by American supermarkets: workstations functioned like a supermarket shelf where the customer can get products they need, at the time they need and in the amount needed, the workstation (shelf) is then restocked. Autonomation was developed by Toyoda Sakichi in Toyoda Spinning and Weaving: an automatically activated loom that was also foolproof, that is automatically detected problems. In 1983 J.N Edwards published his \"MRP and Kanban-American style\" in which he described JIT goals in terms of seven zeros: zero defects, zero (excess) lot size, zero setups, zero breakdowns, zero handling, zero lead time and zero surging. This period also marks the spread of Total Quality Management (TQM) in Japan, ideas initially developed by American authors such as Deming, Juran and Armand V. Feigenbaum. TQM is a strategy for implementing and managing quality improvement on an organizational basis, this includes: participation, work culture, customer focus, supplier quality improvement and integration of the quality system with business goals. Schnonberger identified seven fundamentals principles essential to the Japanese approach:\nMeanwhile, in the sixties, a different approach was developed by George W. Plossl and Oliver W. Wight, this approach was continued by Joseph Orlicky as a response to the TOYOTA Manufacturing Program which led to Material Requirements Planning (MRP) at IBM, latter gaining momentum in 1972 when the American Production and Inventory Control Society launched the \"MRP Crusade\". One of the key insights of this management system was the distinction between dependent demand and independent demand. Independent demand is demand which originates outside of the production system, therefore not directly controllable, and dependent demand is demand for components of final products, therefore subject to being directly controllable by management through the bill of materials, via product design. Orlicky wrote \"Materials Requirement Planning\" in 1975, the first hard cover book on the subject. MRP II was developed by Gene Thomas at IBM, and expanded the original MRP software to include additional production functions. Enterprise resource planning (ERP) is the modern software architecture, which addresses, besides production operations, distribution, accounting, human resources and procurement.\nDramatic changes were occurring in the service industries, as well. Beginning in 1955 McDonald's provided one of the first innovations in service operations. McDonald's is founded on the idea of the production-line approach to service. This requires a standard and limited menu, an assembly-line type of production process in the back-room, high customer service in the front-room with cleanliness, courtesy and fast service. While modeled after manufacturing in the production of the food in the back-room, the service in the front-room was defined and oriented to the customer. It was the McDonald's operations system of both production and service that made the difference. McDonald's also pioneered the idea of franchising this operation system to rapidly spread the business around the country and later the world.\nFedEx in 1971 provided the first overnight delivery of packages in the U.S. This was based on the innovative idea of flying all packages into the single airport in Memphis Tenn by midnight each day, resorting the packages for delivery to destinations and then flying them back out the next morning for delivery to numerous locations. This concept of a fast package delivery system created a whole new industry, and eventually allowed fast delivery of online orders by Amazon and other retailers.\nWalmart provided the first example of very low cost retailing through design of their stores and efficient management of their entire supply chain. Starting with a single store in Roger's Arkansas in 1962, Walmart has now become the world's largest company. This was accomplished by adhering to their system of delivering the goods and the service to the customers at the lowest possible cost. The operations system included careful selection of merchandise, low cost sourcing, ownership of transportation, cross-docking, efficient location of stores and friendly home-town service to the customer.\nIn 1987 the International Organization for Standardization (ISO), recognizing the growing importance of quality, issued the ISO 9000, a family of standards related to quality management systems. There standards apply to both manufacturing and service organizations. There has been some controversy regarding the proper procedures to follow and the amount of paperwork involved, but much of that has improved in current ISO 9000 revisions.\nWith the coming of the Internet, in 1994 Amazon devised a service system of on-line retailing and distribution. With this innovative system customers were able to search for products they might like to buy, enter the order for the product, pay online, and track delivery of the product to their location, all in two days. This required not only very large computer operations, but dispersed warehouses, and an efficient transportation system. Service to customers including a high merchandise assortment, return services of purchases, and fast delivery is at the forefront of this business. It is the customer being in the system during the production and delivery of the service that distinguishes all services from manufacturing.\nRecent trends in the field revolve around concepts such as:\nTopics.\nProduction systems.\nA production system comprises both the technological elements (machines and tools) and organizational behavior (division of labor and information flow). An individual production system is usually analyzed in the literature referring to a single business, therefore it's usually improper to include in a given production system the operations necessary to process goods that are obtained by purchasing or the operations carried by the customer on the sold products, the reason being simply that since businesses need to design their own production systems this then becomes the focus of analysis, modeling and decision making (also called \"configuring\" a production system).\nA first possible distinction in production systems (technological classification) is between continuous process production and discrete part production (manufacturing). \nAnother possible classification is one based on Lead Time (manufacturing lead time vs delivery lead time): engineer to order (ETO), purchase to order (PTO), make to order (MTO), assemble to order (ATO) and make to stock (MTS). According to this classification different kinds of systems will have different customer order decoupling points (CODP), meaning that work in progress (WIP) cycle stock levels are practically nonexistent regarding operations located after the CODP (except for WIP due to queues). (See Order fulfillment)\nThe concept of production systems can be expanded to the service sector world keeping in mind that services have some fundamental differences in respect to material goods: intangibility, client always present during transformation processes, no stocks for \"finished goods\". Services can be classified according to a service process matrix: degree of labor intensity (volume) vs degree of customization (variety). With a high degree of labor intensity there are Mass Services (e.g., commercial banking bill payments and state schools) and Professional Services (e.g., personal physicians and lawyers), while with a low degree of labor intensity there are Service Factories (e.g., airlines and hotels) and Service Shops (e.g., hospitals and auto mechanics).\nThe systems described above are ideal types: real systems may present themselves as hybrids of those categories. Consider, for example, that the production of jeans involves initially carding, spinning, dyeing and weaving, then cutting the fabric in different shapes and assembling the parts in pants or jackets by combining the fabric with thread, zippers and buttons, finally finishing and distressing the pants/jackets before being shipped to stores. The beginning can be seen as process production, the middle as part production and the end again as process production: it's unlikely that a single company will keep all the stages of production under a single roof, therefore the problem of vertical integration and outsourcing arises. Most products require, \"from a supply chain perspective\", both process production and part production.\nMetrics: efficiency and effectiveness.\nOperations strategy concerns policies and plans of use of the firm productive resources with the aim of supporting long term competitive strategy. Metrics in operations management can be broadly classified into efficiency metrics and effectiveness metrics. Effectiveness metrics involve: \nA more recent approach, introduced by Terry Hill, involves distinguishing competitive variables in order winner and order qualifiers when defining operations strategy. Order winners are variables which permit differentiating the company from competitors, while order qualifiers are prerequisites for engaging in a transaction. This view can be seen as a unifying approach between operations management and marketing (see segmentation and positioning).\nProductivity is a standard efficiency metric for evaluation of production systems, broadly speaking a ratio between outputs and inputs, and can assume many specific forms, for example: machine productivity, workforce productivity, raw material productivity, warehouse productivity (=inventory turnover). It is also useful to break up productivity in use U (productive percentage of total time) and yield η (ratio between produced volume and productive time) to better evaluate production systems performances. Cycle times can be modeled through manufacturing engineering if the individual operations are heavily automated, if the manual component is the prevalent one, methods used include: time and motion study, predetermined motion time systems and work sampling.\nABC analysis is a method for analyzing inventory based on Pareto distribution, it posits that since revenue from items on inventory will be power law distributed then it makes sense to manage items differently based on their position on a revenue-inventory level matrix, 3 classes are constructed (A, B and C) from cumulative item revenues, so in a matrix each item will have a letter (A, B or C) assigned for revenue and inventory. This method posits that items away from the diagonal should be managed differently: items in the upper part are subject to risk of obsolescence, items in the lower part are subject to risk of stockout.\nThroughput is a variable which quantifies the number of parts produced in the unit of time. Although estimating throughput for a single process maybe fairly simple, doing so for an entire production system involves an additional difficulty due to the presence of queues which can come from: machine breakdowns, processing time variability, scraps, setups, maintenance time, lack of orders, lack of materials, strikes, bad coordination between resources, mix variability, plus all these inefficiencies tend to compound depending on the nature of the production system. One important example of how system throughput is tied to system design are bottlenecks: in job shops bottlenecks are typically dynamic and dependent on scheduling while on transfer lines it makes sense to speak of \"the bottleneck\" since it can be univocally associated with a specific station on the line. This leads to the problem of how to define capacity measures, that is an estimation of the maximum output of a given production system, and capacity utilization.\nOverall equipment effectiveness (OEE) is defined as the product between system availability, cycle time efficiency and quality rate. OEE is typically used as key performance indicator (KPI) in conjunction with the lean manufacturing approach.\nConfiguration and management.\nDesigning the \"configuration of production systems\" involves both technological and organizational variables. Choices in production technology involve: dimensioning capacity, fractioning capacity, capacity location, outsourcing processes, process technology, automation of operations, trade-off between volume and variety (see Hayes-Wheelwright matrix). Choices in the organizational area involve: defining worker skills and responsibilities, team coordination, worker incentives and information flow.\nIn \"production planning\", there is a basic distinction between the push approach and the pull approach, with the later including the singular approach of just in time. Pull means that the production system authorizes production based on inventory level; push means that production occurs based on demand (forecasted or present, that is purchase orders). An individual production system can be both push and pull; for example activities before the CODP may work under a pull system, while activities after the CODP may work under a push system.\nThe traditional pull approach to inventory control, a number of techniques have been developed based on the work of Ford W. Harris (1913), which came to be known as the economic order quantity (EOQ) model. This model marks the beginning of inventory theory, which includes the Wagner-Within procedure, the newsvendor model, base stock model and the fixed time period model. These models usually involve the calculation of cycle stocks and buffer stocks, the latter usually modeled as a function of demand variability. The economic production quantity (EPQ) differs from the EOQ model only in that it assumes a constant fill rate for the part being produced, instead of the instantaneous refilling of the EOQ model.\nJoseph Orlickly and others at IBM developed a push approach to inventory control and production planning, now known as material requirements planning (MRP), which takes as input both the master production schedule (MPS) and the bill of materials (BOM) and gives as output a schedule for the materials (components) needed in the production process. MRP therefore is a planning tool to manage purchase orders and production orders (also called jobs).\nThe MPS can be seen as a kind of aggregate planning for production coming in two fundamentally opposing varieties: plans which try to chase demand and level plans which try to keep uniform capacity utilization. Many models have been proposed to solve MPS problems:\nMRP can be briefly described as a 3s procedure: sum (different orders), split (in lots), shift (in time according to item lead time). To avoid an \"explosion\" of data processing in MRP (number of BOMs required in input) planning bills (such as family bills or super bills) can be useful since they allow a rationalization of input data into common codes.\nMRP had some notorious problems such as infinite capacity and fixed lead times, which influenced successive modifications of the original software architecture in the form of MRP II, enterprise resource planning (ERP) and advanced planning and scheduling (APS).\nIn this context problems of scheduling (sequencing of production), loading (tools to use), part type selection (parts to work on) and applications of operations research have a significant role to play.\nLean manufacturing is an approach to production which arose in Toyota between the end of World War II and the seventies. It comes mainly from the ideas of Taiichi Ohno and Toyoda Sakichi which are centered on the complementary notions of just in time and autonomation (jidoka), all aimed at reducing waste (usually applied in PDCA style). Some additional elements are also fundamental: production smoothing (Heijunka), capacity buffers, setup reduction, cross-training and plant layout.\nA series of tools have been developed mainly with the objective of replicating Toyota success: a very common implementation involves small cards known as kanbans; these also come in some varieties: reorder kanbans, alarm kanbans, triangular kanbans, etc. In the classic kanban procedure with one card:\nThe two-card kanban procedure differs a bit:\nSince the number of kanbans in the production system is set by managers as a constant number, the kanban procedure works as WIP controlling device, which for a given arrival rate, per Little's law, works as a lead time controlling device.\nIn Toyota the TPS represented more of a philosophy of production than a set of specific lean tools, the latter would include: \nSeen more broadly, JIT can include methods such as: product standardization and modularity, group technology, total productive maintenance, job enlargement, job enrichment, flat organization and vendor rating (JIT production is very sensitive to replenishment conditions).\nIn heavily automated production systems production planning and information gathering may be executed via the control system, attention should be paid however to avoid problems such as deadlocks, as these can lead to productivity losses.\nProject Production Management (PPM) applies the concepts of operations management to the execution of delivery of capital projects by viewing the sequence of activities in a project as a production system. Operations managements principles of variability reduction and management are applied by buffering through a combination of capacity, time and inventory.\nService operations.\nService industries are a major part of economic activity and employment in all industrialized countries comprising 80 percent of employment and GDP in the U.S. Operations management of these services, as distinct from manufacturing, has been developing since the 1970s through publication of unique practices and academic research. Please note that this section does not particularly include \"Professional Services Firms\" and the professional services practiced from this expertise (specialized training and education within).\nAccording to Fitzsimmons, Fitzsimmons and Bordoloi (2014) differences between manufactured goods and services are as follows:\nThese four comparisons indicate how management of service operations are quite different from manufacturing regarding such issues as capacity requirements (highly variable), quality assurance (hard to quantify), location of facilities (dispersed), and interaction with the customer during delivery of the service (product and process design).\nWhile there are differences there are also many similarities. For example, quality management approaches used in manufacturing such as the Baldrige Award, and Six Sigma have been widely applied to services. Likewise, lean service principles and practices have also been applied in service operations. The important difference being the customer is in the system while the service is being provided and needs to be considered when applying these practices.\nOne important difference is service recovery. When an error occurs in service delivery, the recovery must be delivered on the spot by the service provider. If a waiter in a restaurant spills soup on the customer's lap, then the recovery could include a free meal and a promise of free dry cleaning. Another difference is in planning capacity. Since the product cannot be stored, the service facility must be managed to peak demand which requires more flexibility than manufacturing. Location of facilities must be near the customers and scale economics can be lacking. Scheduling must consider the customer can be waiting in line. Queuing theory has been devised to assist in design of service facilities waiting lines. Revenue management is important for service operations, since empty seats on an airplane are lost revenue when the plane departs and cannot be stored for future use.\nMathematical modeling.\nThere are also fields of mathematical theory which have found applications in the field of operations management such as operations research: mainly mathematical optimization problems and queue theory. Queue theory is employed in modelling queue and processing times in production systems while mathematical optimization draws heavily from multivariate calculus and linear algebra. Queue theory is based on Markov chains and stochastic processes. Computations of safety stocks are usually based on modeling demand as a normal distribution and MRP and some inventory problems can be formulated using optimal control.\nWhen analytical models are not enough, managers may resort to using simulation. Simulation has been traditionally done through the discrete event simulation paradigm, where the simulation model possesses a state which can only change when a discrete event happens, which consists of a clock and list of events. The more recent transaction-level modeling paradigm consists of a set of resources and a set of transactions: transactions move through a network of resources (nodes) according to a code, called a process.\nSince real production processes are always affected by disturbances in both inputs and outputs, many companies implement some form of quality management or quality control. The Seven Basic Tools of Quality designation provides a summary of commonly used tools:\nThese are used in approaches like total quality management and Six Sigma. Keeping quality under control is relevant to both increasing customer satisfaction and reducing processing waste.\nOperations management textbooks usually cover demand forecasting, even though it is not strictly speaking an operations problem, because demand is related to some production systems variables. For example, a classic approach in dimensioning safety stocks requires calculating the standard deviation of forecast errors. Demand forecasting is also a critical part of push systems, since order releases have to be planned ahead of actual clients’ orders. Also, any serious discussion of capacity planning involves adjusting company outputs with market demands.\nSafety, risk and maintenance.\nOther important management problems involve maintenance policies (see also reliability engineering and maintenance philosophy), safety management systems (see also safety engineering and Risk management), facility management and supply chain integration.\nOrganizations.\nThe following organizations support and promote operations management:\nJournals.\nThe following high-ranked academic journals are concerned with operations management issues:", "Engineering,_Manufacturing": 0.9998114705, "qwen": "Yes"}
{"id": "11377310", "revid": "5837138", "url": "https://en.wikipedia.org/wiki?curid=11377310", "title": "Apple Dot Matrix Printer", "text": "The Apple Dot Matrix Printer (often shortened to Apple DMP) is a printer manufactured by C. Itoh and sold under the Apple Computer, Inc. label in 1982 for the Apple II series, Lisa, and the Apple III. It was succeeded by the ImageWriter in 1984.\nThe Apple DMP is the last parallel port printer sold under the Apple label; all subsequent Apple printers (ImageWriter, ImageWriter II, Scribe, LaserWriter, etc.) were serial port printers.", "Engineering,_Manufacturing": 0.9999908209, "qwen": "Yes"}
{"id": "2001956", "revid": "5229428", "url": "https://en.wikipedia.org/wiki?curid=2001956", "title": "Computer-aided production engineering", "text": "Computer-aided production engineering (CAPE) is a relatively new and significant branch of engineering. Global manufacturing has changed the environment in which goods are produced. Meanwhile, the rapid development of electronics and communication technologies has required design and manufacturing to keep pace.\nDescription of CAPE.\nCAPE is seen as a new type of computer-aided engineering environment which will improve the productivity of manufacturing/industrial engineers. This environment would be used by engineers to design and implement future manufacturing systems and subsystems. Work is currently underway at the United States National Institute of Standards and Technology (NIST) on CAPE systems. The NIST project is aimed at advancing the development of software environments and tools for the design and engineering of manufacturing systems.\nCAPE and the Future of Manufacturing.\nThe future of manufacturing will be determined by the efficiency with which it can incorporate new technologies. The current process in engineering manufacturing systems is often ad hoc, with computerized tools being used on a limited basis. Given the costs and resources involved in the construction and operation of manufacturing systems, the engineering process must be made more efficient. New computing environments for engineering manufacturing systems could help achieve that objective.\nWhy is CAPE important? In much the same way that product designers need computer-aided design systems, manufacturing and industrial engineers need sophisticated computing capabilities to solve complex problems and manage the vast data associated with the design of a manufacturing system.\nIn order to solve these complex problems and manage design data, computerized tools must be used in the application of scientific and engineering methods to the problem of the\ndesign and implementation of manufacturing systems. Engineers must address the entire factory as a system and the interactions of that system with its surrounding environment.\nComponents of a factory system include:\nCAPE must not only be concerned with the initial design and engineering of the factory, it must also address enhancements over time. CAPE should support standard engineering methods and problem-solving techniques, automate mundane tasks, and provide reference data to support the decision-making process.\nThe environment should be designed to help engineers become more productive and effective in their work. This would be implemented on personal computers or engineering workstations which have been configured with appropriate peripheral devices. Engineering tool developers will have to integrate the functions and data used by a number of different disciplines, for example:\nMany of the methods, formulas, and data associated with these technical areas currently exist only in engineering handbooks. Although some computerized tools are available, they are often very specialized, difficult to use, and do not share information or work together. Engineering tools built by different vendors must be made compatible through open systems architectures and interface standards.\nWhat CAPE will look like.\nCAPE will be based upon computer systems providing an integrated set of design and engineering tools. These software tools will be used by a company's manufacturing engineers to continuously improve its production systems. They will maintain information about manufacturing resources, enhance production capabilities, and develop new facilities and systems. Engineers working on different workstations will share information through a common database.\nUsing CAPE, an engineering team will prepare detailed plans and working models for an entire factory in a matter of days. Alternative solutions to production problems could be quickly developed and evaluated. This would be a significant improvement over current manual methods which may require weeks or months of intensive activity.\nTo achieve this goal, a new set of engineering tools are needed. Examples of functions which should be supported include:\nThe tools implementing these functions must be highly automated and integrated; and will need to provide quick access to a wide range of data. This data must be maintained in a format that is accessible and usable by the engineering tools. Some examples of the information that might be contained in these electronic libraries include:\nThese on-line libraries would allow engineers to quickly develop solutions based upon the work of others.\nAnother critical aspect of this engineering environment is affordability, which\ncan best be achieved by designing an environment that can be constructed from low cost \"off-the-shelf\" commercial products, rather than custombuilt computer hardware and software. The basic engineering environment must be affordable. For both cost and technical reasons, it must be designed to be able to support incremental upgrades. Incremental upgrades would allow companies to add capabilities as they are needed. Commercial software products must be easy to install and integrate with other software already in use. These capabilities exist to a limited extent in some general purpose commercial software today, e.g., word processors, databases, spreadsheets.\nTechnical Concerns.\nMany technical issues must be considered in the design and development of new engineering tools for CAPE. These issues include:\nThere are three critical elements to be addressed: creating a common manufacturing systems information model; using an engineering life cycle approach; and developing a software tool integration framework.\nResolution of these elements will help ensure that independently developed systems will be able to work together. The common information model should identify the elements of the manufacturing system and their relationships to each other; the functions or processes performed by each element; the tools, materials, and information required to perform those functions; and measures of effectiveness for the model and its component elements.\nThere have been many efforts over the years to develop information models for different\naspects of manufacturing, but no known existing model fully meets the needs of a CAPE ernviroment. Therefore, a life cycle approach is needed to identify the different processes that a CAPE environment must support, and must define all phases of a manufacturing system or subsystem's existence. Some of the major phases which may be included in a system life cycle approach are, requirements identification; system design specification; vendor selection; system development and upgrades; installation, testing, and training; and benchmarking of production operations.\nManagement, coordination, and administration functions need to be performed during each phase of the life cycle. Phases may be repeated over time as a system is upgraded or re-engineered to meet changing needs or incorporate new technologies.\nA software tool integration framework should specify how the tools could be independently designed and developed. The framework would define how CAPE tools would deal with common services, interact with each other and coordinate problem solving activities. Although some existing software products and standards currently address the common services issue, the problem of tool interaction remains largely unsolved. The problem of tool interaction is not limited to the domain of computer-aided manufacturing systems engineering—it is pervasive across the software industry.\nCAPE's current state.\nAn initial CAPE environment has been established from commercial off-the-shelf (COTS) software packages. This new environment is being used to demonstrate commercially available tools to perform CAPE functions, to develop a better understanding and define functional requirements for individual engineering tools and the overall environment, and to identify the integration issues which must be addressed to implement compatible environments in the future.\nSeveral engineering demonstrations using COTS tools are under development. These demonstrations are designed to illustrate the various types of functions that must be performed in engineering a manufacturing system.\nFunctions supported by the current COTS environment include: system specification/diagramming,\nprocess flowcharting, information modeling, computer-aided design of products, plant layout, material flow analysis, ergonomic workplace design, mathematical modeling, statistical analysis, line balancing, manufacturing simulation, investment analysis, project management, knowledge-based system development, spreadsheets, document preparation, user interface development, document illustration, forms and database management.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "46964830", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=46964830", "title": "Inkjet technology", "text": "Inkjet technology originally was invented for depositing aqueous inks on paper in 'selective' positions based on the ink properties only. Inkjet nozzles and inks were designed together and the inkjet performance was based on a design. It was used as a data recorder in the early 1950s, later in the 1950s co-solvent-based inks in the publishing industry were seen for text and images, then solvent-based inks appeared in industrial marking on specialized surfaces and in the1990's phase change or hot-melt ink has become a popular with images and digital fabrication of electronic and mechanical devices, especially jewelry. Although the terms \"jetting\", \"inkjet technology\" and \"inkjet printing\", are commonly used interchangeably, inkjet printing usually refers to the publishing industry, used for printing graphical content, while industrial jetting usually refers to general purpose fabrication via material particle deposition. \nMany companies have worked with inkjet over the years. Many patents have been issued and the technology has been used in a number of products. The basic form of the inkjet was a single nozzle with either fluid forced through under pressure, pulled from it by electrical potential or pushed out with the help of a piezo. Single nozzle inkjets will be discussed first in this introduction. Inkjet technology was pioneered by Teletype Corporation in the 1960s which introduced the \"electronic pull\", high voltage drop extraction from a nozzle, Inktronic Teleprinter in 1965 printing at 120 characters per second (cps) from a row of 40 inkjets using the Charles R. Winston patent, Method and Apparatus for Transferring Inks, 1962, US3,060,429. Teletype experimented with \"hot-melt\" wax inks as described in a Teletype patent by Johannes F. Gottwald, Liquid Metal Recorder, 1971, US 3,596,285, that outputs a fabricated metal symbol (Stock exchange symbols and quotes) able to be removed from the conveyor carrier and the Bismuth metal alloy reused if desired. The use of Hot-melt inks with a newer Drop-On-Demand inkjet technology(invented by Zoltan in 1972) with these inks would not be seen again until 1984 at Howtek and Exxon.\nHowtek was started as R.H Research in 1982 by Robert Howard after successfully growing Centronics, the first dot-matrix solenoid-driven wire ribbon impact printer company in 1968. Howard calculated his solenoid matrix printer was 10-20 times faster than Teletype. Howard had tested making dots on paper by using ultrasonic sound in the late 1960s but did not advance the idea until some 20 years later in 1984 with Howtek when he hired 6 key employees from Exxon to develop his hot-melt color inkjet printer idea..\nExxon Office Systems(EOS), Brookfield, Ct plunged into the non-impact printer business in the late 1970s and invested as much as $2 billion. Patent records show a lengthy list of printing background employees at the EOS, Exxon Enterprises, Danbury Systems Division starting in 1978 including Ken Bower who was recruited by Exxon to found the engineering department at Exxon Enterprises. Ken's first job out of college in 1963 was at AT&T's Teletype, Division in Skokie, IL where his job was to transition an electro-mechanical stock exchange ticker (inkjet printer) into production. On his first day of work he smelled wax and was shown a 42 jet printer with heated printheads that was under development. Ken went on to work at UARCO business forms and made associations with developers of On-Demand inkjet, including Steve Zoltan at Gould and Silonics under Ed Kyser and Stephen Sears. Steve Zoltan was using the cylindrical piezoelectric tube with cylindrical compression and Ed Keyser was using a flat piezoelectric diaphragm that squirted ink like an oil can.\nTwo employees hired at Exxon (EOS) with no experience in printing were James McMahon and Kathy Olson. McMahon was hired to install the first Zoltan style single-nozzle inkjet, code name \"Alpha Jet\" to a fax printer and Olson was hired to build the \"Alpha\" jets for fax printer production. McMahon and Olson (married name McMahon) were two of the six employees hired by Robert Howard to design and build on-demand inkjets for the Pixelmaster color printer. Within 6 months of joining R.H Research(name changed to Howtek) the Alpha jet print samples with hot-melt ink were being shown at COMDEX, in Las Vegas. J. McMahon is credited with an Improved Inkjet System using the Zoltan technology at EOS and K. McMahon is credited with nozzle manufacturing techniques at Howtek. J. McMahon went on to work at Sanders Prototype(Solidscape) 3D printer manufacturer and is now employed at Layer Grown Model Technology supporting On-demand single-nozzle inkjets and claims to be the godfather of 3D Inkjet single-nozzle technology as a historian who worked in the field since 1978 with Steve Zoltan and Ken Bower at Exxon. 3D Inkjet single-nozzle printing has a direct path from Teletype hot-melt inks (Wax and metal alloy) to Steve Zoltan's single-nozzle jetting technology that never developed at Exxon with glass nozzles but became reality at Howtek with Teflon molded nozzles and heated printheads in 1984. An ex-Howtek employee, Richard Helinski is credited for the patent using two materials to produce particle deposition articles in 3D using Howtek style inkjets and thermoplastic inks. These same Howtek inkjets and materials were used in the Ballistic Particle Manufacturing, Personal Modeler and the Visual Impact Corporation, Sculptor 3D printer businesses that have since closed. These printers and original Howtek style inkjets and materials can be seen at the 3D Inkjet Collection in New Hampshire, the only historical collection of Zoltan style inkjets and 3D printers. Single nozzle jets are still in use today in Solidscape 3D printers and are considered to produce a very high quality model.\nApplications.\nSome inks must have high conductivity, high oxidation resistance and low sintering temperature while others are for other applications.\nDrop formation.\nVarious drop formation technologies exist, and can be classified into two main types: continuous inkjet (CIJ) and drop-on-demand (DOD).\nWhile CIJ has a straightforward drop creation and sophisticated drop trajectory manipulation, DOD has sophisticated drop creation and 'some' trajectory manipulation and alternate nozzle designs are possible. This single-nozzle inkjet technology is still in its early stages for those who want to investigate.\nA Howtek inkjet nozzle uses a tubular thin wall piezo that produces a sound wave in the fluid chamber reflecting off both ends of the nozzle. The leading edge of a square wave signal triggers it and the lagging edge of the square wave signal in coincidence with the pressure wave expels the drop. This DOD single jet is acoustic. The 120C Tefzel nozzle is not rigid and does not squeeze. Drop formation is controlled by the fluid properties and nozzle geometry. Drive pulse amplitude and timing play a major role in drop volume and formation. Generally, DOD technology can be very complicated to understand and use.\nDrop-on-demand (DOD).\nIn this method, drops of ink are released individually, on demand, by a voltage signal. Released drops either fall vertically without any trajectory manipulation or require special fire timing when projected horizontally from a rotary printhead spinning at 121 RPM to form characters (Howtek color printer 1986). Commercial printheads can have a single nozzle (Solidscape) or thousands of nozzles (HP) and many other variations in between. Arrayed Inkjet Apparatus (John G Martner patent 4468680, 1984 Exxon Research and Engineering Co) was invented after testing a Piezo DOD epoxied on the end of a piano wire 30 inches long and inserted into an ink fluid chamber leading to a nozzle. The tiny piezo either was pulling the wire in and out of the fluid chamber or transmitting a sound wave through the wire to impart acoustic energy into the fluid to fire a drop. The object of the invention was to build a printhead to reduce crosstalk (sound or any energy into closely placed nozzles for text printing).\nThe two leading technologies for forcing ink out of a nozzle on demand are thermal DOD and piezoelectric DOD. Notice the DOD may use a \"Fill before firing a drop\" or \"Fire before fill\" and Thermal DOD just \"fires before fill\". Drops must be precisely controlled with Piezo DOD or Thermal DOD. A standard Piezo DOD can fire drops at 9 feet per second drop velocity. Piezo DOD drop target positioning is very accurate with every drop fired horizontally or vertically.\nAdditional technologies include electrospray, acoustic discharge, electrostatic membrane and thermal bimorph.\nPiezoelectric DOD.\nPiezoelectric Drop-On-Demand (DOD) was invented in the 1970s. One disadvantage of the piezoelectric-DOD method is that jettable inks must have viscosity and surface tension within a relatively strict range to expel smaller drops without spray or satellite drops. One big advantage is DOD piezoelectric jets can be designed to work with high temperature Thermoplastics and other hot-melt inks in the temperature range of 100-130C. This allows for three-dimensional droplets to be printed on substrates and makes investment casting and 3D modelling possible. The Richard Helinski 3D patent US5136515A started a new era in inkjet printing. Helinski's experience at Howtek, Inc from 1984 -1989 and his many other patents including subtractive color (layering colored drops) with suggestions from a fellow inventor/employee, Alan Hock, about investment casting encouraged this patent. The patent is focused on printing complex solid 3D objects printed with a clean burning material when placed in an investment casting process primarily in the jewelry industry but also favored by electronics, automotive and medical industries in the early 1990s. Howtek style inkjets and Thermoplastic materials were created to print documents and images and later Braille characters.\nThere are many patents and methods to expel drops with piezoelectric devices. A piezo changes shape when voltage is applied. The amount of dimensional change is extremely small. A Piezo also be made in many different sizes. The smaller the piezo the smaller the shape displacement. The use of a DOD piezo to print a text character (the size of these letters) requires the piezo to be placed side by side in a housing. Drops must be smaller than .005 inches and be placed precisely in lines to form letters. A Piezo placed side by side at frequencies high enough to print a full sheet of paper vibrate loudly and effect the drops nearby. Drop-On-Demand (DOD) printheads have manufacturing limits with single nozzles. Multi-jet DOD printing is most common with inkjet printers for this reason.\nThermal inkjet (TIJ) DOD.\nThermal DOD was introduced in the 1980s by Canon and Hewlett-Packard. Thermal printing does not use high-temperature inks.\nOne disadvantage of this method is that the variety of inks compatible with TIJ is essentially limited, because this method is compatible with inks that have high vapour pressure, low boiling point and high kogation stability. Water's being such a solvent limited the popularity of this method for non-industrial photo printing only, where water-based inks are used.\nContinuous inkjet (CIJ).\nIn this method, a stream of ink is released continuously from the nozzle. A garden hose jet stream is a good example of a continuous flow from a nozzle except CIJ nozzles are tiny (less than .005 inch or about 1/10 millimeter). The ink stream naturally breaks into separate drops due to Plateau–Rayleigh flow instability. Fluid streams can be broken into different size drops with vibration from a piezoelectric device. The use of a piezoelectric device should not be confused with Drop-On-Demand Inkjet which uses the piezo to generate sound waves in nozzles or expand the fluid chamber size to push single drops from a nozzle. The CIJ formed ink drops are either deflected by an electric field towards the desired location on the substrate or collected for reuse. CIJ printheads can be either have a single jet (nozzle) or multiple jets. CIJ is popular in industry and publishing but not typically seen in retail printers for home use.\nOne disadvantage of the CIJ method is the need for solvent monitoring. Since only a small fraction of the ink is being used for actual printing, solvent must be continually added to the recycled ink to compensate the evaporation that takes place during flight of the recycled drops.\nAnother disadvantage is the need for ink additives. Since this method is based on electrostatic deflection, ink additives, such as potassium thiocyanate, may deteriorate the performance of the printed devices.\nCIJ can be directed through a magnetic field using low-temperature metal alloy ink as described in Johannes F Gottwald's Liquid Metal Recorder patent US3596285A, issued on July 27, 1971. The .003-inch aperture glass nozzle printed stock market quote symbols on a moving metal substrate belt and dropped on the table to be used as signage or reused in the recorder to print other symbols. This was possibly the earliest example of printing \"fabricated objects\" with an inkjet.\nPrinthead.\nThe printhead must have heating capability to print any material influenced by viscosity changes. Oil-based inks are sensitive to temperature. Waxes and hot-melt materials are solids at room temperature. Water-based inks may not need heat. It is also possible to print with metallic alloys such as lead, tin, indium, zinc and aluminum. The process of printing of low-melting point metals is called \"direct melt printing\" and was introduced in 1971 by Johannes F Gottwald patent, US3596285, \"Liquid Metal Recording\" with a Continuous inkjet (CIJ) long before any form of 3D Printing was ever considered. Thermoplastic DOD inkjets print at or above the piezoelectric Curie temperature and must be continuously poled to work. Piezo D33 displacement had to be optimized to lower drive voltages. See \"Piezo-response force microscopy\" for relevant theory. Prior research in 1980 by James McMahon about the six piezo physical poling states and tests to maximize piezo resonant and anti-resonant frequencies sped up the development time. Howtek manufactured these state of the art inkjets in 1985 before 3D printing with inkjets was invented on 8/4/1992. \nOriginal DOD inkjet printheads were made of glass in 1972 by Steve Zoltan. These early single nozzle inkjet printheads printed with water-based inks. Later a housing was needed to surround the inkjet with a stable thermal mass. Glass inkjet nozzles were hard to duplicate and the molded nozzles were introduced by Howtek, Inc. Howtek glass nozzles had to be made with heat by a torch and drawn glass tubes, then cut to size and polished to produce a flat nozzle orifice surface. Glass nozzle technology was better understood by one inventor, Laszlo Halasz in the 1980s and he could form different nozzle shapes by using heated oil to melt glass capillaries. Howtek introduced single-tubular Tefzel molded nozzles using a stainless steel core pin – blind molded and then sliced with a razor to expose the orifice in perfect shape. Howtek produced its own full-color thermoplastic- ink material printing letterhead sheets in the rotary-head Pixelmaster printer in 1986 with 32 single nozzles (eight for each primary color). The Tefzel nozzle material operating at 125C allowed only the voltage pulse energy to trigger an acoustical pressure wave in the fluid without coupling the high-frequency vibrations from the piezo that cause spray and fluid vibration as the drops are ejected. The ideas for the design came from a book discovered by Jim McMahon in 1972, Harry F Olson's \"Music, Physics and Engineering\". Earlier inkjet designs with glass nozzles were also resonance sources and when packed with vibration dampening material could never eliminate spray. The object of the design was to have clean spray-free drops ejected over the frequency range of the nozzle length. The Howtek jets run nicely from 1 to 16,000 Hertz. No other company has produced printheads with this design to this day. The Tefzel nozzle with a long tapered front fluid chamber absorbed unwanted harmonics and allowed only the hydraulic fluid surge from the individual piezo drive pulse to eject a drop. One drive pulse equaled one drop at all frequencies up to the fluid resonance for the tube length. The square wave pulse leading edge triggered a sound wave in the fluid that reflected off the tail end of the nozzle tube and was reinforced when the lagging edge of the drive pulse was passing under the center of the piezo to boost the fluid pressure sufficiently to expel one single drop. The speed of sound for each of the two inks (wax and Thermoplastic) differs resulting in two maximum resonance frequencies for the same inkjet nozzle structure. Thus one Howtek printhead design works for two different inks. The Howtek inkjet nozzle is unique in so many ways. The design requires a strict assembly sequence and manufacturing process.\nOne 3D printer in use in 2021 (Solidscape) still has a Howtek style nozzle as it was manufactured in 1986. It originally had a hex-shaped metal nozzle-end structure with an offset-nozzle orifice that allowed the jet drops to be (aimed) directed toward a target to align properly for the best print quality when it was previously installed in the Howtek Pixelmaster. Over 1500 Howtek style inkjets were acquired by early Sanders Prototype, Inc when production of the Modelmaker 6 Pro was first started in 1994. The Modelmaker 6 pro uses two inkjets per machine. The inkjets are installed in a special printhead directing the drops straight downward for 3D printing. The original prototype 3D printer, the Sculptor by Visual Impact Corporation, using Howtek nozzles, printed horizontally in 1989. The Pixelmaster also projected the drops horizontally from a 121 rpm rotating printhead to print 2D characters or images on paper. A Braille character printer was introduced by Howtek and only sold a few machines in 1990–1991 with raised-font printed on plain paper using Howtek inkjets. This required four layers of drops to stack up for each Braille character. This was an early example of how three-dimensional (ink) material printing (not called 3D printing in 1984) got started and now-a-days Additive Manufacturing (AM) does not reference historical jetting of hot-melt material properties used in 3D printing. 3D printing (printing with raised surface inks) was inkjet printing in the 1960–1980s with wax, liquid metal and thermoplastic hot-melt fluids.\nFabrication approaches.\nThe printed material is rarely only one step in the process, which may include direct material deposition followed by a mechanical roller or a controlled surface milling step. It may be a deposition of a precursor followed by a catalyst, sintering, photonic curing, electroless plating etc., to give the final result. See Ballistic Particle Manufacturing(BPM)which uses a Solid ink single nozzle, heated to 125C and a 5 axis printing technique that required no other process for fabrication.\nInkjet fluid materials.\nThe ink must be liquid, but may also contain small solids if they do not cause clogging. The solid particles should be smaller than 1/10 of the nozzle diameter to avoid clogging and be smaller than 2 microns to reduce satellite drop spray. Fine detail inkjet printing has material filtered by 1 micron filters to prevent spray and fluid lines protected by 15 micron filters to prevent clogging.\nDrop formation is governed by two main physical properties: surface tension and viscosity. The surface tension forms ejected drops into spheres, in accordance with Plateau–Rayleigh instability. The viscosity can be optimized at jet time by using an appropriate printhead temperature. Drop volume is controlled by drive pulse timing width and drive voltage amplitude. Each inkjet assembly will have a slight variation in drop size and maintaining all material and jet parameters is necessary for optimum performance. Drop formation and volume varies with drop frequency and jet orifice meniscus position. The liquid is positioned in the nozzle aperture by gravity (fluid storage tank must be slightly lower in height to the nozzle). The fluid surface tension also holds the fluid at the edge of the nozzle orifice (hole). The action of expelling a drop alters this natural steady fluid position condition. This condition is commonly called the meniscus of the fluid. The meniscus acts like a barrier and most be overcome to allow drop ejection. The meniscus also exerts strong forces when stretched. The lower the storage tank height the higher the force required to expel a drop. The meniscus spring action timing alters the drop size, drop velocity and drive voltage in drops formation. Firing drops more frequently means the characteristics of the drop change constantly because of meniscus position. Each jettable material has different physical properties and requires different printer parameters and tank height settings. Materials can not just be switched. The temperature of the inkjet must be more closely controlled to maintain surface tension and viscosity in a DOD system than in a CIJ system.\nGenerally, lower viscosity allows better droplet formation and in practice only liquids with viscosity of 2-50 mPa s can be printed. More precisely, liquids whose Ohnesorge number is larger than 0.1 and smaller than 1 are jettable.", "Engineering,_Manufacturing": 0.9999521971, "qwen": "Yes"}
{"id": "11821707", "revid": "85186", "url": "https://en.wikipedia.org/wiki?curid=11821707", "title": "Timeline of intelligent design", "text": "This timeline of intelligent design outlines the major events in the development of intelligent design as presented and promoted by the intelligent design movement.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "10318354", "revid": "19404073", "url": "https://en.wikipedia.org/wiki?curid=10318354", "title": "Varian, Inc.", "text": "Varian, Inc. was one of the largest manufacturers of scientific instruments for the scientific industry. They had offerings over a broad range of chemical analysis equipment, with a particular focus on Information Rich Detection and Vacuum technology. Varian was spun off from Varian Associates in 1999 and was purchased by Agilent Technologies in May 2010 for $1.5 billion, or $52 per share.\nVarian Inc. had its corporate headquarters in Palo Alto, California, and offices in Australia, the Benelux countries, Brazil, Canada, China, Germany, France, Italy, Japan, Korea, Russia, Sweden, Taiwan, the United Kingdom, and the United States.\nManufacturing plants.\nVarian Inc. contained the following manufacturing plants: \nHistory.\nIn October 1967, Techtron Pty Ltd merged with Varian Associates. Techtron is a manufacturer of Atomic Absorption Spectrometers and Spectral lamps.\nIn 1982 Varian transferred the Cary UV-Visible product line to Australia.\nIn 1997 Varian bought Chemagnetics, a Colorado-based manufacturer of solid-state NMR spectrometers.\nIn 2002 Varian bought Ansys Technologies, Inc., a California-based manufacturer of In-Vitro Medical Devices.\nIn 2004 Varian Inc bought Magnex Scientific, an Oxford-based manufacturer of high-field magnets.\nIn 2005 Varian bought Polymer Laboratories, a speciality polymer analysis and manufacturing company.\nIn 2006 Varian bought Ion Spec, an FTMS (Fourier Transform Mass Spectrometry) manufacturing company.\nIn 2007, Varian, Inc. bought Analogix, Inc., a company specializing in flash chromatography.\nIn 2008, Varian bought Oxford Diffraction, a British company specializing in X-ray diffraction equipment.\nOn 27 July 2009 Agilent Technologies announced it would buy Varian Inc, for $1.5 Billion.\nOn 14 October 2014 Agilent made the strategic decision to close its NMR business. Agilent entered the NMR business in 2010, with the acquisition of Varian.", "Engineering,_Manufacturing": 0.9992362261, "qwen": "Yes"}
{"id": "10323080", "revid": "36315429", "url": "https://en.wikipedia.org/wiki?curid=10323080", "title": "Production leveling", "text": "Production leveling, also known as production smoothing or – by its Japanese original term – , is a technique for reducing the mura (unevenness) which in turn reduces muda (waste). It was vital to the development of production efficiency in the Toyota Production System and lean manufacturing. The goal is to produce intermediate goods at a constant rate so that further processing may also be carried out at a constant and predictable rate.\nWhere demand is constant, production leveling is easy, but where customer demand fluctuates, two approaches have been adopted: 1) \"demand leveling\" and 2) \"production leveling\" through flexible production.\nTo prevent fluctuations in production, even in outside affiliates, it is important to minimize fluctuation in the final assembly line. Toyota's final assembly line never assembles the same automobile model in a batch. Instead, they level production by assembling a mix of models in each batch and the batches are made as small as possible.\nProduction leveling by volume or by product type or mix.\nProduction leveling can refer to leveling by volume, or leveling by product type or mix, although the two are closely related.\nLeveling by volume.\nIf for a family of products that use the same production process there is a demand that varies between 800 and 1,200 units then it might seem a good idea to produce the amount ordered. Toyota's view is that production systems that vary in the required output suffer from mura and muri with capacity being 'forced' in some periods. So their approach is to manufacture at the long-term average demand and carry an inventory proportional to the variability of demand, stability of the production process and the frequency of shipments. So for our case of 800–1,200 units, if the production process were 100% reliable and the shipments once a week, then the production would be with minimum standard inventory of 200 at the start of the week and 1,200 at the point of shipment. The advantage of carrying this inventory is that it can smooth production throughout the plant and therefore reduce process inventories and simplify operations which reduces costs.\nLeveling by product.\nMost value streams produce a mix of products and therefore face a choice of production mix and sequence. It is here that the discussions on economic order quantities take place and have been dominated by changeover times and the inventory this requires. Toyota's approach resulted in a different discussion where it reduced the time and cost of changeovers so that smaller and smaller batches were not prohibitive and lost production time and quality costs were not significant. This meant that the demand for components could be leveled for the upstream sub-processes and therefore lead time and total inventories reduced along the entire value stream. To simplify leveling of products with different demand levels a related visual scheduling board known as a heijunka box is often used in achieving these heijunka style efficiencies. Other production leveling techniques based on this thinking have also been developed. Once leveling by product is achieved then there is one more leveling phase, that of \"Just in Sequence\" where leveling occurs at the lowest level of product production.\nThe use of production leveling as well as broader lean production techniques helped Toyota massively reduce vehicle production times as well as inventory levels during the 1980s.\nImplementation.\nEven Toyota hasn't reached the final stage in this journey, single-piece flows, across all of their processes; indeed they recommend following their journey rather than trying to jump into an intermediate stage. The reason Toyota advocates this is that each production stage is accompanied by adjustments and adaptations to support services to production; if those services are not given these adaptation steps then major issues can arise.\nDemand leveling.\nDemand leveling is the deliberate influencing of demand itself or the demand processes to deliver a more predictable pattern of customer demand. Some of this influencing is by manipulating the product offering, some by influencing the ordering process and some by revealing the demand amplification induced variability of ordering patterns. Demand levelling does not include influencing activities designed to clear existing stock.\nHistorically demand leveling evolved as subset of production levelling and has been approached in a variety of ways:\nImplementation.\nIf it is accepted that a large part of demand variability in high volume products can be substantially caused by sales and ordering process artifacts then analysis and leveling can be attempted.\nThe use of long delay supply chains to reduce manufacturing costs often means that production orders are placed long before customer demand can be realistically estimated. The much later arrival of forecast product demand volumes makes demand leveling irrelevant since the issue has now switched to disposal at best price possible products that are already created and possibly paid for. Demand leveling has only proven possible where build times have been made relatively low and production has been made relatively reliable and flexible. Examples of these are fast airborne supply chains (e.g. Apple iPod) or direct to customer selling through web sites allowing late customisation (e.g. NIKEiD custom shoes) or local manufacture (e.g. Timbuk2 custom courier bags).\nWhere actual build-delivery times can be brought within the same scale as customer time horizons then effort to modify impulse buying and make it somewhat planned can be successful. Reliable, flexible manufacturing will then mean that low stock levels (if any) do not interfere with customer satisfaction and that incentives to sell what has been produced eliminated.\nWhere demand follows a predictable pattern, e.g. flat, then regular deliveries of constant amounts can be agreed with variances in actual demand ignored unless it exceeds some agreed trigger level. Where this cannot be agreed then it can be simulated and the benefits gained through frequent deliveries and a market location.\nThe predictable pattern does not have to be flat and may, for example, be an annual pattern with higher volumes at particular periods. Here again the deliveries can be agreed to follow a simplified but similar pattern, perhaps one delivery volume for six months of the year and another for the other six months.", "Engineering,_Manufacturing": 1.0000019073, "qwen": "Yes"}
{"id": "10323156", "revid": "332841", "url": "https://en.wikipedia.org/wiki?curid=10323156", "title": "Fixed repeating schedule", "text": "Fixed repeating schedule is a key element of the Toyota Production System and lean manufacturing. As its name suggests it is a production schedule which is 'unchanging' and repeated perhaps daily or over a longer period such as two weeks or month. If it can be implemented, economies of repetition start to become evident and suppliers and customers can be assured in their own activity scheduling. What impedes this being implemented is the uncertainty of demand and supply. Therefore whilst the scheduling becomes simple, the activities to make the scheduling possible become more complex. Thus the planning to move to FRS reveals issues which, if managed correctly, will reduce complexity overall and improve customer service.\nHistory.\nFixed repeating schedules have been invented all over the place by many organisations as local solutions. Perhaps Ford's early production technique was a trivial example since by ensuring only one product, the black model T, the scheduling became simple as well.\nThe first widely publicised example with a systematic development was in the Toyota Production System where an FRS smooths flow in the factory and therefore reduces the waste of unevenness (or mura).\nImplementation.\nStep 1: red stream/green stream.\nSince in all but the trivial example of constant demand there will actually be fluctuations in required production, FRS is only part of a scheduling solution. The challenge in the early steps of implementation is to isolate the maximum part of production that can be fixed from the part of production that cannot. This isolation, at least in the early stages, should extend to the supporting services as well as the value adding process or gemba itself. Thus procurement, stock keeping, deliveries and so on should be run separately for the fixed and non-fixed schedules. For example, this means two procurement 'contracts'; one for fixed deliveries of fixed amounts at regular intervals and one for deliveries as otherwise requested. If this disciple in not complete then the uncertainties in the unfixed side will 'leak' back into the fixed side which will then become unfixed for lack of resources.\nTo enforce this separation some factories have actually split the factory into two different parts with each part being represented and painted a different colour. This separation went as far as painting forklift trucks, tools, floor areas and stock containers in their corresponding colour as well as selecting staff based upon their temperament to work on one side or the other. The German factory director believed it was as close as he could come to actually running two factories, one FRS and the other flexible.\nThe benefit of this work was the significant cost decreases that occurred in the FRS 'factory' which far outweighed the slight increase in costs in the flexible 'factory'. In the FRS 'factory' all costs and activities will be repeated which allows significant process simplifications and time and cost reductions to occur across all functions. This is because the 'exceptions' to the standard process will no longer occur and schedules will always be achieved so that process failure 'safety net' processes and equipment and staff can be eliminated or re-deployed.\nThese benefits only accrue whilst the green stream/FRS products or services remain predictable in demand. Therefore it is critical to ensure appropriate frequency reviews of product demand to ensure promotion of stable products from the red stream and demotion of now less stable demand products to the red stream. This may follow product maturity curves where, after initial introduction, when demand stabilises products move into the FRS and then later, when purchase enthusiasm wanes, they are removed again. Seasonality can be built into FRS by having, for example, a summer and a winter fixed schedule.\nStep 2: speed up the FRS.\nThe implementation of step 1 will have allowed people in the 'FRS' factory to run simpler processes and to establish routines that were not possible in the schedule, reschedule, reschedule world that existed before, and may still exist in the 'non-FRS factory'. This will make the work more manageable and simplify the communications in the 'factory' that are so critical to performance. Because of this it will become much clearer what sub-processes are limiting production capability and therefore which operations can be simplified and improved. It is often the case that large stock levels pre-existed, or were built to make FRS 'possible', the actual causes of these stocks can now be addressed by operational improvements to reduce lot sizes and improve reliability. Once these have been done and supporting services have also adjusted then the aim is to shorten the period of the repeat in 'FRS'. This planning and then action will surface new issues along the lines of the earlier phase which should in their turn be managed as a priority. The shortening of the cycle will allow the reduction of finished goods and WIP stocks as well whilst maintaining availability of stocks for customers. This cycle should be repeated until management nerve breaks.\nFor Toyota the implementation of a fixed repeating schedule is one of the early steps in achieving production levelling which follows further steps to achieve lower lot sizes gain the lower costs and flexibility this makes possible.", "Engineering,_Manufacturing": 0.9997285008, "qwen": "Yes"}
{"id": "10333611", "revid": "172822", "url": "https://en.wikipedia.org/wiki?curid=10333611", "title": "Cylindrical grinder", "text": "The cylindrical grinder is a type of grinding machine used to shape the outside of an object. The cylindrical grinder can work on a variety of shapes, however the object must have a central axis of rotation. This includes but is not limited to such shapes as a cylinder, an ellipse, a cam, or a crankshaft. \nCylindrical grinding is defined as having four essential actions: \nWhile the majority of cylindrical grinders employ all four movements, there are grinders that only employ three of the four actions.\nHistory.\nThe origins of the cylindrical grinder, as with all other modern machine tools, stem from the experimentation and invention of John Wilkinson and later Henry Maudslay who built the first horizontal boring machine and the first engine lathe, respectively. The cylindrical grinder owes much of its development from the onset of the Industrial Revolution, particularly to the advent of reliable, inexpensive steel production and later the improvement of the grinding wheel. The basis for the modern day cylindrical grinder was first built in the 1830s by two men working independently, Jonathan Bridges and James Wheaton . It is unclear as to which man had first produced the machine but both are closely tied to the first historical appearance of the modern day tool. It took another 40 years before further improvement and refinement of the tool occurred.\nThe Brown & Sharpe company in Providence, RI was one of the first builders of the Willcox & Gibbs Sewing Machine, one of the first piece of precision machinery to be used in a residential setting. Joseph Brown believed that the shaft and needle bars of the sewing machine must be crafted from hardened tool steel. It was this desire that led to their experimentation with building a cylindrical grinder. The first attempt was simply a small lathe with a grinding wheel mounted to it. Subsequent attempts led to the cylindrical grinder displayed at the 1876 Centennial Exposition and the subsequent patent.\nIt is important to note that Brown & Sharpe cannot be given sole credit of pioneering advances in cylindrical grinding. A man in Waltham, Massachusetts, Ambrose Webster had created a small grinding machine in 1860 that contained all of the improvements Brown & Sharpe claimed to be their own original invention. Even more so, the emphasis on precision, accuracy, and reliability was championed by Charles Norton.\nNorton was an employee of Brown & Sharpe who quit the company with the desire to further pursue his belief that the cylindrical grinder is not merely a finishing tool but could be a staple of the machine shop. He founded the Norton Grinding Company, where he continued improving the cylindrical grinder to use faster rpm values and more precise grinding tolerances. He was acknowledged for his work on April 18, 1925 when he won The John Scott Medal and Premium for his invention of \"accurate grinding devices of high power\". These standards developed by Norton were the status quo until about the middle of the 20th century.\nThe remainder of technological innovation applicable to the cylindrical grinder is almost identical and entangled in a sense, to the rest of machine tools. The innovation of the last 70 years can be characterized by three waves of change. The first wave was the creation of numerical control by John T. Parsons in the 1940s. The U.S. Air Force, looking for a faster, cheaper, and more efficient means of part and tool production for airplanes, played a large role in developing NC both politically and financially. The first implementation of NC in machine tools occurred in the 1950s and continued through the 1960s. The second wave of innovation, occurring during the 1970s and 1980s, is marked by the massive demand for microcomputers to be used to direct NC. The joining of computers marked the birth of Computer Numerical Control which once again revolutionized the ability of the cylindrical grinder. Now the machine was able to receive instruction from a computer which would give it precise directions on every imaginable dimension and measurement needed to produce the desired product. This was a completely different work environment in comparison to mid-century production where a worker had to direct the machine at every point on how to manipulate the work. The third wave of change came in the 1990s with the advent of the Personal Computer. Integrating CNC and the PC into one dynamic system allowed for even further control of the manufacturing process that required little to no human supervision.\nMethods.\nThere are five different types of cylindrical grinding: outside diameter (OD) grinding, inside diameter (ID) grinding, plunge grinding, creep feed grinding, and centerless grinding.\nOutside diameter grinding.\nOD grinding is grinding occurring on external surface of an object between the centers. The centers are end units with a point that allow the object to be rotated. The grinding wheel is also being rotated in the same direction when it comes in contact with the object. This effectively means the two surfaces will be moving opposite directions when contact is made which allows for a smoother operation and less chance of a jam up.\nInside diameter grinding.\nID grinding is grinding occurring on the inside of an object. The grinding wheel is always smaller than the width of the hole being ground. The object is held in place by a collet, which also rotates the object in place. Just as with OD grinding, the grinding wheel and the object rotated in opposite directions giving reversed direction contact of the two surfaces where the grinding occurs.\nSee also ID Grinding.\nPlunge grinding.\nA form of OD grinding, however the major difference is that the grinding wheel makes continuous contact with a single point of the object instead of traversing the object.\nCreep feed grinding.\nCreep Feed is a form of grinding where a full depth of cut is removed in a single pass of the wheel. Successful operation of this technique can reduce manufacturing time by 50%, but often the grinding machine being used must be designed specifically for this purpose. This form occurs in both cylindrical and surface grinding.\nCenterless grinding.\nCenterless grinding is a form of grinding where there is no collet or pair of centers holding the object in place. Instead, there is a regulating wheel positioned on the opposite side of the object to the grinding wheel. A work rest keeps the object at the appropriate height but has no bearing on its rotary speed. The workblade is angled slightly towards the regulating wheel, with the workpiece centerline above the centerlines of the regulating and grinding wheel; this means that high spots do not tend to generate corresponding opposite low spots, and hence the roundness of parts can be improved. Centerless grinding is much easier to combine with automatic loading procedures than centered grinding; through feed grinding, where the regulating wheel is held at a slight angle to the part so that there is a force feeding the part through the grinder, is particularly efficient.\nControl methods.\nThere are three basics ways in which an operator can interact with a cylindrical grinder. Either manual manipulation of the machine, Numerical Control with a punched card system or using Computer Numerical Control using a pre existing interface designed for that machine or by using a PC as an interface to communicate with the grinder. The first two options are rarely if ever used today. CNC operated cylindrical grinders are the most technologically advanced, efficient, reliable systems in the manufacturing industry.\nApplications.\nThe cylindrical grinder is responsible for a plethora of innovations and inventions in the progression of science and technology. Any situation in which extremely precise metalworking is required, the cylindrical grinder is able to provide a high level of precision. From the automotive industry to military applications, the benefits of the cylindrical grinder are numerous.", "Engineering,_Manufacturing": 0.999999404, "qwen": "Yes"}
{"id": "10334744", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=10334744", "title": "Alloy wheel", "text": "In the automotive industry, alloy wheels are wheels that are made from an alloy of aluminium or magnesium. Alloys are mixtures of a metal and other elements. They generally provide greater strength over pure metals, which are usually much softer and more ductile. Alloys of aluminium or magnesium are typically lighter for the same strength, provide better heat conduction, and often produce improved cosmetic appearance over steel wheels. Although steel, the most common material used in wheel production, is an alloy of iron and carbon, the term \"alloy wheel\" is usually reserved for wheels made from nonferrous alloys.\nThe earliest light-alloy wheels were made of magnesium alloys. Although they lost favor on common vehicles, they remained popular through the 1960s, albeit in very limited numbers. In the mid-to-late 1960s, aluminium-casting refinements allowed the manufacture of safer wheels that were not as brittle. Until this time, most aluminium wheels suffered from low ductility, usually ranging from 2-3% elongation. Because light-alloy wheels at the time were often made of magnesium (often referred to as \"mags\"), these early wheel failures were later attributed to magnesium's low ductility, when in many instances these wheels were poorly cast aluminium alloy wheels. Once these aluminium casting improvements were more widely adopted, the aluminium wheel took the place of magnesium as low cost, high-performance wheels for motorsports.\nCharacteristics.\nLighter wheels can improve handling by reducing unsprung mass, allowing suspension to follow the terrain more closely and thus improve grip, however not all alloy wheels are lighter than their steel equivalents. Reduction in overall vehicle mass can also help to reduce fuel consumption.\nBetter heat conduction and a more open wheel design can help dissipate heat from the brakes, which improves braking performance in more demanding driving conditions and reduces the chance of diminished brake performance or even failure due to overheating.\nAlloy wheels are also purchased for cosmetic purposes although the cheaper alloys used are usually not corrosion-resistant. Alloys allow the use of attractive bare-metal finishes, but these need to be sealed with paint or wheel covers. Even if so protected the wheels in use will eventually start to corrode after 3 to 5 years but refurbishment is now widely available at a cost. The manufacturing processes also allow intricate, bold designs. In contrast, steel wheels are usually pressed from sheet metal, and then welded together (often leaving unsightly bumps) and must be painted to avoid corrosion and/or hidden with wheel covers/hub caps.\nAlloy wheels are prone to galvanic corrosion, which can cause the tires to leak air if appropriate preventive measures are not taken. Also, alloy wheels are more difficult to repair than steel wheels when bent, but their higher price usually makes repairs cheaper than replacement.\nAlloy wheels are more expensive to produce than standard steel wheels, and thus are often not included as standard equipment, instead being marketed as optional add-ons or as part of a more expensive trim package. However, alloy wheels have become considerably more common since 2000, now being offered on economy and subcompact cars, compared to a decade earlier where alloy wheels were often not factory options on inexpensive vehicles. Alloy wheels have long been included as standard equipment on higher-priced luxury or sports cars, with larger-sized or \"exclusive\" alloy wheels being options. The high cost of alloy wheels makes them attractive to thieves; to counter this, automakers and dealers often use locking lug nuts or bolts which require a special key to remove.\nMost alloy wheels are manufactured using casting, but some are forged. Forged wheels are usually lighter, stronger, but much more expensive than cast wheels. There are two types of forged wheels: one piece and modular. Modular forged wheels may feature two- or three-piece design. Typical multi-piece wheels consist of the inner rim base, outer rim lip and wheel center piece with openings for lug nuts. All parts of a modular wheel are held with bolts. BBS RS is one of the most famous three-piece modular forged wheels.\nAftermarket wheels.\nA sizable selection of alloy wheels are available to automobile owners who want lighter, more visually appealing, rarer, and/or larger wheels on their cars, going from 14 and 15 inch standard wheels up to 16, 17, 18, 19, 20, 21, 22, 24, 26, 28 and 30 inch wheel sizes. With the larger alloy wheels came Tru-Spinner Wheels and spinner wheel add-on spinners that would free-spin and continue to free-spin after the alloy wheel itself came to rest. American inventor James JD Gragg of International and American Tru-Spinners were the original ones and were leaders in the industry. Another function of Tru-Spinners was they could also spin backward as the alloy wheel was rolling forward. Although replacing standard steel wheel and tire combinations with lighter alloy wheels and potentially lower profile tires can result in increased performance and handling, this doesn't necessarily hold when increasingly large wheels are employed. Research by \"Car and Driver\" conducted using a selection of differently sized alloy wheels from all outfitted with the same make and model of tires showed that both acceleration and fuel economy suffered with larger wheels. They also noted that ride comfort and noise were negatively affected by the larger wheels.\nMagnesium alloy wheels.\nMagnesium alloy wheels were the first die-cast wheels produced, and were often referred to as simply \"mag wheels.\" Magnesium wheels were originally used for racing, but their popularity during the 1960s led to the development of other die-cast wheels, particularly of aluminium alloys. The term \"mag wheels\" became synonymous with die-cast wheels made from any material, from modern aluminium alloy wheels to plastic and composite wheels used on items like bicycles, wheelchairs, and skateboards.\nHowever, pure magnesium wheels are no longer produced, being found only on classic cars. Pure magnesium suffers from many problems. Vintage magnesium rims were very susceptible to pitting, cracking and corrosion. Magnesium in bulk is hard to ignite but pure magnesium wheels can be ignited by a burning tire or by prolonged scraping of the wheel on the road surface following a puncture. Alloys of magnesium were later developed to alleviate most of these problems. In fact, US Federal Aviation Administration has conducted wide-ranging tests over the past decade, and has reached a conclusion that potential flammability of magnesium is no longer deemed to be a concern. Modern surface treatment technologies provide protection from corrosion and significantly extend the average lifecycle of magnesium rims.\nProduction methods.\nForging.\nForging can be done by a one or multistep process forging from various magnesium alloys, most commonly AZ80, ZK60 (MA14 in Russia). Wheels produced by this method are usually of higher toughness and ductility than aluminium wheels, although the costs are much higher. Forging is a complicated process that involves such processes, as heating, rolling, applying high pressure, hammering and/or combination of these. As a result, the crystal structure of the alloy changes, and as a result the material becomes stronger and more lightweight.\nAssembly.\nThere are one- two- and three-piece forged wheels. Every piece is originally an alloy billet, which is further transformed into a wheel, in cases of one-piece forged wheels, or into a wheel part in cases of multi-piece wheels.\nHigh pressure die casting.\nThis process uses a die arranged in a large machine that has high closing force to clamp the die closed. The molten magnesium is poured into a filler tube called a shot sleeve. A piston pushes the metal into the die with high speed and pressure, the magnesium solidifies, and the die is opened, and the wheel is released. Wheels produced by this method can offer reductions in price and improvements in corrosion resistance, but they are less ductile and of lower strength due to the nature of high pressure die casting.\nLow pressure die casting.\nThis process usually employs a steel die, it is arranged above the crucible filled with molten magnesium. Most commonly, the crucible is sealed against the die and pressurized air/cover gas mix is used to force the molten metal up a straw-like filler tube into the die.\nWhen processed using best practice methods, low pressure die casting wheels can offer improvements in ductility over magnesium wheels and any cast aluminium wheels, they remain less ductile than forged magnesium.\nGravity casting.\nGravity-cast magnesium wheels have been in production since the early 1920s and provide good ductility, and relative properties above what can be made with aluminium casting. Tooling costs for gravity-cast wheels are among the cheapest of any process. This has allowed small batch production, flexibility in design and short development time.", "Engineering,_Manufacturing": 0.9997825027, "qwen": "Yes"}
{"id": "23669193", "revid": "9929111", "url": "https://en.wikipedia.org/wiki?curid=23669193", "title": "Undercut (manufacturing)", "text": "In manufacturing, an undercut is a special type of recessed surface that is inaccessible using a straight tool. In turning, it refers to a recess in a diameter generally on the inside diameter of the part. In milling, it refers to a feature which is not visible when the part is viewed from the spindle. In molding, it refers to a feature that cannot be molded using only a single pull mold. In printed circuit board construction, it refers to the portion of the copper that is etched away under the photoresist.\nTurning.\nOn turned parts an undercut is also known as a \"neck\" or \"relief groove\". They are often used at the end of the threaded portion of a shaft or screw to provide clearance for the cutting tool.\nMolding.\nUndercut - Any indentation or protrusion in a shape that will prevent its withdrawal from a one-piece mold.\nMilling.\nIn milling the spindle is where a cutting tool is mounted. In some situations material must be cut from a direction where the feature can not be seen from the perspective of the spindle and requires special tooling to reach behind the visible material. \nThe corners may be undercut to remove the radius that is usually left by the milling cutter this is commonly referred to as a relief.\nEtching.\nUndercuts from etching (microfabrication) are a side effect, not an intentional feature.", "Engineering,_Manufacturing": 0.9995935559, "qwen": "Yes"}
{"id": "23678615", "revid": "437261", "url": "https://en.wikipedia.org/wiki?curid=23678615", "title": "Recoil pad", "text": "A recoil pad is a piece of rubber, foam, leather, or other soft material usually attached to the buttstock of a rifle or shotgun. Recoil pads may also be worn around the shoulder with straps, placing the soft material between the buttstock and the shoulder of the person firing the gun. The purpose of this device is to provide additional padding between the typically hard buttstock surface and the user's shoulder, to reduce the amount of felt recoil of the firearm, and to prevent slippage on the shooter's clothing while aiming.", "Engineering,_Manufacturing": 0.9990586638, "qwen": "Yes"}
{"id": "11474573", "revid": "3170772", "url": "https://en.wikipedia.org/wiki?curid=11474573", "title": "Excelsior-Henderson Motorcycle", "text": "Excelsior-Henderson Motorcycle was a motorcycle manufacturing company located in Belle Plaine, Minnesota in the late 1990s.\nHistory.\nThe company was originally founded as Hanlon Manufacturing Company by Daniel Hanlon during early 1993 in Burnsville, Minnesota, United States. The company secured the rights of motorcycle names previously used by the former Excelsior-Henderson company, that was owned by Ignatz Schwinn of the Schwinn company. The company proceeded to design and manufacture OEM proprietary motorcycles with design originality of the former Excelsior and Henderson motorcycles.\nFactory.\nFrom 1997 to 1998, the company constructed a factory in Belle Plaine, Minnesota. The factory was equipped for a capacity of 10,000 motorcycles per year, and, with a few minor assembly and finishing line changes, would have had a capacity of 20,000. In 2009, the factory was converted to the headquarters of Cambria, a company specializing in quartz surfaces.\nProduction.\nExcelsior-Henderson introduced it first production model, the Super X, in December 1998, and commenced production in early 1999. The company developed the Super X motorcycle as a new proprietary motorcycle, including a new engine, frame, and all related drive and styling components, adopting styling from the earlier Excelsior-Henderson motorcycles from the 1905-1931 timeframe. The company established 140 dealers throughout the United States. The motorcycles averaged an MSRP around $18,500. Via the assembly line, the company produced for retail sale approx. 1900 motorcycles in various configurations; 1161 units in model year 1999, and 720 units in model year 2000. In total, the company produced an estimated 1950 motorcycles, which would include motorcycles produced and not designed for retail dealer sales; such as dealer promotional bikes, test prototypes and non-assembly line produced motorcycles.\nChapter 11 Bankruptcy.\nExcelsior-Henderson, having spent $100 million in capital over a seven year period and still several years from profitability, was unable to raise additional capital by late 1999. Therefore, on December 21, 1999, Excelsior-Henderson filed for reorganization under Chapter 11, Title 11, United States Code. As an outcome of the process, certain assets of the company were sold to a Florida investment group, which later filed for reorganization and no longer exists. Production of motorcycles never recommenced. According to former employees, the company’s failures can be attributed to ineptitude in growing a dealer network, micromanaging, and an unwillingness to accept and incorporate suggestion. Gary Fields, Deputy Commissioner of Minnesota’s Department of Trade and Economic Development, said that the state would be less likely to fund another startup based on the failures of Excelsior-Henderson. \nCurrent Status.\nOn 16 December 2020, Cycle World reported Excelsior-Henderson's intellectual property had been purchased by Bajaj, a major manufacturer of motorcycles in India.", "Engineering,_Manufacturing": 0.996520102, "qwen": "Yes"}
{"id": "66110715", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=66110715", "title": "Slot-die coating", "text": "Slot-die coating is a coating technique for the application of solution, slurry, or extruded thin films onto typically flat substrates such as glass, metal, paper, fabric or plastic foils. The process was first developed for the industrial production of photographic papers in the 1950's. It has since become relevant in numerous commercial processes and nanomaterials related research fields.\nSlot-die coating produces thin films via solution processing. The desired coating material is typically dissolved or suspended into a precursor solution or slurry (sometimes referred to as \"ink\") and delivered onto the surface of the substrate through a precise coating head known as a slot-die. The slot-die has a high aspect ratio outlet controlling the final delivery of the coating liquid onto the substrate. This results in the continuous production of a wide layer of coated material on the substrate, with adjustable width depending on the dimensions of the slot-die outlet. By closely controlling the rate of solution deposition and the relative speed of the substrate, slot-die coating affords thin material coatings with easily controllable thicknesses in the range of 10 nanometers to hundreds of micrometers after evaporation of the precursor solvent.\nCommonly cited benefits of the slot-die coating process include its pre-metered thickness control, non-contact coating mechanism, high material efficiency, scalability of coating areas and throughput speeds, and roll-to-roll compatibility. The process also allows for a wide working range of layer thickness and precursor solution properties such as material choice, viscosity, and solids content. Commonly cited drawbacks of the slot-die coating process include its comparatively high complexity of apparatus and process optimization relative to similar coating techniques such as blade coating and spin coating. Furthermore, slot-die coating falls into the category of coating processes rather than printing processes. It is therefore better suited for coating of uniform, thin material layers rather than printing or consecutive buildup of complex images and patterns.\nCoating apparatus.\nTypical components.\nSlot-die coating equipment is available in a variety of configurations and form factors. However, the vast majority of slot-die processes are driven by a similar set of common core components. These include:\nDepending on the complexity of the coating apparatus, a slot-die coating system may include additional modules for e.g. precise positioning of the slot-die over the substrate, particulate filtering of the coating solution, pre-treatment of the substrate (e.g. cleaning and surface energy modification), and post-processing steps (e.g. drying, curing, calendering, printing, slitting, etc.).\nIndustrial coating systems.\nSlot-die coating was originally developed for industrial use and remains primarily applied in production-scale settings. This is due to its potential for large-scale production of high-value thin films and coatings at a low operating cost via roll-to-roll and sheet-to-sheet line integration. Such roll-to-roll and sheet-to-sheet coating systems are similar in their intent for large-scale production, but are distinguished from each other by the physical rigidity of the substrates they handle. Roll-to-roll systems are designed to coat and handle flexible substrate rolls such as paper, fabric, plastic or metal foils. Conversely, sheet-to-sheet systems are designed to coat and handle rigid substrate sheets such as glass, metal, or plexiglass. Combinations of these systems such roll-to-sheet lines are also possible.\nBoth industrial roll-to-roll and sheet-to-sheet systems typically feature slot-dies in the range of 300 to 1000 mm in coating width, though slot-dies up to 4000 mm wide have been reported. Commercial slot-die systems are claimed to operate at speeds up to several hundred square meters per minute, with roll-to-roll systems typically offering higher throughput due to decreased complexity of substrate handling. Such large-scale coating systems can be driven by a variety of industrial pumping solutions including gear pumps, progressive cavity pumps, pressure pots, and diaphragm pumps depending on process requirements.\nRoll-to-roll lines.\nTo handle flexible substrates, roll-to-roll lines typically use a series of rollers to continually drive the substrate through the various stations of the process line. The bare substrate originates at an \"unwind\" roll at the start of the line and is collected at a \"rewind\" roll at the end. Hence, the substrate is often referred to as a \"web\" as it winds its way through the process line from start to finish. When a substrate roll has been fully processed, it is collected from the rewind roll, allowing for a new, bare substrate roll to be mounted onto the unwind roller to begin the process again. Slot-die coating often comprises just a single step of an overall roll-to-roll process. The slot-die is typically mounted in a fixed position on the roll-to-roll line, dispensing coating fluid onto the web in a continuous or patch-based manner as the substrate passes by. Because the substrate web spans all stations of the roll-to-roll line simultaneously, the individual processes at these stations are highly coupled and must be optimized to work in tandem with each other at the same web speed.\nSheet-to-sheet lines.\nThe rigid substrates employed in sheet-to-sheet systems are not compatible with the roll-to-roll processing method. Sheet-to-sheet systems rely instead on a rack-based system to transport individual sheets between the various stations of a process line, where transfer between stations may occur in a manual or automated manner. Sheet-to-sheet lines are therefore more analogous to a series of semi-coupled batch operations rather than a single continuous process. This allows for easier optimization of individual unit operations at the expense of potentially increased handling complexity and reduced throughput. Furthermore, the need to start and stop the slot-die coating process for each substrate sheet places higher tolerance requirements on the leading and trailing edge uniformity of the slot-die step. In sheet-to-sheet lines, the substrate may be fixed in place as the substrate passes underneath on a moving support bed (sometimes referred to as a \"chuck\"). Alternatively, the slot-die may move during coating while the substrate remains fixed in place.\nLab-scale development tools.\nMiniaturized slot-die tools have become increasingly available to support the development of new roll-to-roll compatible processes prior to the requirement of full pilot- and production-scale equipment. These tools feature similar core components and functionality as compared to larger slot-die coating lines, but are designed to integrate into pre-production research environments. This is typically achieved by e.g. accepting standard A4 sized substrate sheets rather than full substrate rolls, using syringe pumps rather than industrial pumping solutions, and relying upon hot-plate heating rather than large industrial drying ovens, which can otherwise reach lengths of several meters to provide suitable residence times for drying.\nBecause the slot-die coating process can be readily scaled between large and small areas by adjusting the size of the slot-die and throughput speed, processes developed on lab-scale tools are considered to be reasonably scalable to industrial roll-to-roll and sheet-to-sheet coating lines. This has led to significant interest in slot-die coating as a method of scaling new thin film materials and devices, particularly in the sphere of thin film solar cell research for e.g. perovskite and organic photovoltaics.\nCommon coating modalities.\nSlot-die hardware can be applied in several distinct coating modalities, depending on the requirements of a given process. These include:\nThe dynamics of proximity coating have been extensively studied and applied over a wide range of scales and applications. Furthermore, the concepts governing proximity coating are relevant in understanding the behavior of other coating modalities. Proximity coating is therefore considered to be the default configuration for the purposes of this introductory article, though curtain coating and tensioned web over slot die configurations remain highly relevant in industrial manufacturing.\nKey process parameters.\nFilm thickness control.\nSlot-die coating is a non-contact coating method, in which the slot-die is typically held over the substrate at a height several times higher than the target wet film thickness. The coating fluid transfers from the slot-die to the substrate via a fluid bridge that spans the air gap between the slot-die lips and substrate surface. This fluid bridge is commonly referred to as the coating meniscus or coating bead. The thickness of the resulting wet coated layer is controlled by tuning the ratio between the applied volumetric pump rate and areal coating rate. Unlike in self-metered coating methods such as blade- and bar coating, the slot-die does not influence the thickness of the wet coated layer via any form of destructive physical contact or scraping. The height of the slot-die therefore does not determine the thickness of the wet coated layer. The height of the slot-die is instead significant in determining the quality of the coated film, as it controls the distance that must be spanned by the meniscus to maintain a stable coating process.\nformula_1\nSlot-die coating operates via a pre-metered liquid coating mechanism. The thickness of the wet coated layer (formula_2) is therefore significantly determined by the width of coating (formula_3), the volumetric pump rate (formula_4), and the coating speed, or relative speed between the slot-die and the substrate during coating (formula_5). Increasing the pump rate increases the thickness of the wet layer, while increasing the coating speed or coating width decreases the wet layer thickness. The coating width is typically a fixed value for a given slot-die process. Hence, pump rate and coating speed can be used to calculate, control, and adjust the wet film thickness in a highly predictable manner. However, deviation from this idealized relationship can occur in practice due to non-ideal behavior of materials and process components; for example when using highly viscoelastic fluids, or a sub-optimal process setup where fluid creeps up the slot-die component rather than transferring fully to the substrate.\nformula_6\nThe final thickness of the dry layer after solvent evaporation (formula_7) is further determined by the solids concentration of the precursor solution (formula_8) and the volumetric density of the coated material in its final form (formula_9). Increasing the solids content of the precursor solution increases the thickness of the dry layer, while using a more dense material results a thinner dry layer for a given concentration.\nFilm quality control.\nAs with all solution processed coating methods, the final quality of a thin film produced via slot-die coating depends on a wide array of parameters both intrinsic and external to the slot-die itself. These parameters can be broadly categorized into:\nCoating window parameters.\nUnder ideal conditions, the potential to achieve a defect-free film via slot-die is entirely governed by the coating window of the a given process. The coating window is a multivariable map of key process parameters, describing the range over which they can be applied together to achieve a defect-free film. Understanding the coating window behavior of a typical slot-die process enables operators to observe defects in a slot-die coated layer and intuitively determine a course of action for defect resolution. The key process parameters used to define the coating window typically include:\nThe coating window can be visualized by plotting two such key parameters against each other while assuming the others to remain constant. In an initial simple representation, the coating window can be described by plotting the relationship between viable pump rates and coating speeds for a given process. Excessive pumping or insufficient coating speeds result in defect spilling of the coating liquid outside of the desired coating area, while coating too quickly or pumping insufficiently results in defect breakup of the meniscus. The pump rate and coating speed can therefore be adjusted to directly compensate for these defects, though changing these parameters also affects wet film thickness via the pre-metered coating mechanism. Implicit in this relationship is the effect of the slot-die height parameter, as this affects the distance over which the meniscus must be stretched while remaining stable during coating. Raising the slot-die higher can thus counteract spilling defects by stretching the meniscus further, while lowering the slot-die can counteract streaking and breakup defects by reducing the gap that the meniscus must breach. Other helpful coating window plots to consider include the relationship between fluid capillary number and slot-die height, as well as the relationship between pressure across the meniscus and slot-die height. The former is particularly relevant when considering changes in fluid viscosity and surface tension (i.e. the effect of coating various materials with significantly different rheology), while the latter is relevant in the context of applying a vacuum box at the upstream face of the meniscus to stabilize the meniscus against breakup.\nDownstream process effects.\nIn reality, the final quality of a slot-die coated film is heavily influenced by a variety of factors beyond the parameter boundaries of the ideal coating window. Surface energy effects and drying effects are examples of common downstream effects with a significant influence on final film morphology. Sub-optimal matching of surface energy between the substrate and coating fluid can cause dewetting of the liquid film after it has been applied to the substrate, resulting in pinholes or beading of the coated layer. Sub-optimal drying processes are also often noted to influence film morphology, resulting in increased thickness at the edge of a film caused by the coffee ring effect. Surface energy and downstream processing must therefore be carefully optimized to maintain the integrity of the slot-die coated layer as it moves through the system, until the final thin film product can be collected.\nExternal effects.\nSlot-die coating is a highly mechanical process in which uniformity of motion and high hardware tolerances are critical to achieving uniform coatings. Mechanical imperfections such as jittery motion in the pump and coating motion systems, poor parallelism between the slot-die and substrate, and external vibrations in the environment can all lead to undesired variations in film thickness and quality. Slot-die coating apparatus and its environment must therefore be suitably specified to meet the needs of a given process and avoid hardware- and environment-derived defects in the coated film.\nApplications.\nIndustrial applications.\nSlot-die coating was originally developed for the commercial production of photographic films and papers. In the past several decades it has become a critical process in the production of adhesive films, flexible packaging, transdermal and oral pharmaceutical patches, LCD panels, multi-layer ceramic capacitors, lithium-ion batteries and more.\nResearch applications.\nWith growing interest in the potential of nanomaterials and functional thin film devices, slot-die coating has become increasingly applied in the sphere of materials research. This is primarily attributed to the flexibility, predictability and high repeatability of the process, as well as its scalability and origin as a proven industrial technique. Slot-die coating has been most notably employed in research related to flexible, printed, and organic electronics, but remains relevant in any field where scalable thin film production is required.\nExamples of research enabled by slot-die coating include:", "Engineering,_Manufacturing": 0.9999334812, "qwen": "Yes"}
{"id": "6142621", "revid": "1157707788", "url": "https://en.wikipedia.org/wiki?curid=6142621", "title": "Balancing machine", "text": "A balancing machine is a measuring tool used for balancing rotating machine parts such as rotors for electric motors, fans, turbines, disc brakes, disc drives, propellers and pumps. The machine usually consists of two rigid pedestals, with suspension and bearings on top supporting a mounting platform. The unit under test is bolted to the platform and is rotated either with a belt-, air-, or end-drive. As the part is rotated, the vibration in the suspension is detected with sensors and that information is used to determine the amount of unbalance in the part. Along with phase information, the machine can determine how much and where to add or remove weights to balance the part.\nHard-bearing vs. soft-bearing.\nThere are two main types of balancing machines, hard-bearing and soft-bearing. The difference between them, however, is in the suspension and not the bearings.\nIn a hard-bearing machine, balancing is done at a frequency lower than the resonance frequency of the suspension. Thus the suspension's resulting displacement is caused by the centrifugal force generated by the unbalance of the rotor. In a soft-bearing machine, balancing is done at a frequency higher than the resonance frequency of the suspension. The suspension's displacement is dictated by the distance of the rotor's principal axis of inertia relative to the rotor's rotational axis defined by the rotor bearings. Both types of machines have various advantages and disadvantages. A hard-bearing machine is generally more versatile and can handle pieces with greatly varying weights, because hard-bearing machines are measuring centrifugal forces and require only a one-time calibration. Only five geometric dimensions need to be fed into the measuring unit and the machine is ready for use. Therefore, it works very well for low- and middle-size volume production and in repair workshops.\nA soft-bearing machine is not so versatile with respect to amount of rotor weight to be balanced. The preparation of a soft-bearing machine for individual rotor types is more time consuming, because it needs to be calibrated for different part types which makes the process accuracy dependent on the operator's knowledge and skill. With measuring equipment capable of storing the setup calibration parameters, the need for recalibration becomes unnecessary as long as the original rotor setup on the balancing machine at the time of its calibration is duplicated. Thus use of dedicated fixture for each type of rotor may come at additional cost but offers the advantage of better balancing process accuracy and less dependent on the machine operator's skill level. With the machine setup a little bit more tedious, it is generally more suitable for high-production volume and high-precision balancing tasks. The latter being required when the rotor has a high service speed, or critical application (see ISO 201940 for recommended balancing tolerance.)\nHard- and soft-bearing machines can be automated to remove weight automatically, such as by drilling or milling, but hard-bearing machines are more robust and reliable. Both machine principles can be integrated into a production line and loaded by a robot arm or gantry, requiring very little human control.\nHow it works.\nWith the rotating part resting on the bearings, a vibration sensor is attached to the suspension. In most soft-bearing machines, a velocity sensor is used. This sensor works by moving a magnet in relation to a fixed coil that generates voltage proportional to the velocity of the vibration. Accelerometers, which measure acceleration of the vibration, can also be used.\nA photocell (sometimes called a phaser), proximity sensor, or encoder is used to determine the rotational speed, as well as the relative phase of the rotating part. This phase information is then used to filter the vibration information to determine the amount of movement, or force, in one rotation of the part. Also, the time difference between the phase and the vibration peak gives the angle at which the unbalance exists. Amount of unbalance and angle of unbalance give an unbalance vector.\nCalibration is performed by adding a known weight at a known angle. In a soft-bearing machine, trial weights must be added in correction planes for each part. This is because the location of the correction planes along the rotational axis is unknown, and therefore it is unknown how much a given amount of weight will affect the balance. By using trial weights, a known weight at a known angle is added, and getting the unbalance vector caused by it.\nOther balancing machine types.\nStatic balancing machines differ from hard- and soft-bearing machines in that the part is not rotated to take a measurement. Rather than resting on its bearings, the part rests vertically on its geometric center. Once at rest, any movement by the part away from its geometric center is detected by two perpendicular sensors beneath the table and returned as unbalance. Static balancers are often used to balance parts with a diameter much larger than their length, such as fans. The advantages of using a static balancer are speed and price. However a static balancer can only correct in one plane, so its accuracy is limited.\nA blade balancing machine attempts to balance a part in assembly, so minimal correction is required later on. Blade mass balancing is typically done for short blades, while long blades may require moment weighing in one or two axes. Long blades that are also wide may require its axial moment to be measured to optimize hub stress distribution. Blade balancers are used on parts such as fans, propellers, and turbines. On a blade balancer, the weight and/or moment of each blade to be assembled is entered into a balancing software package. The software then sorts the blades and attempts to find the blade arrangement with the least amount of unbalance. Lesser amount of unbalance correction weight in the final balancing process means lesser (concentrated) stress to the rotor assembly. \nPortable balancing machines are used to balance parts that cannot be taken apart and put on a balancing machine, usually parts that are currently in operation such as turbines, pumps, and motors. Portable balancers come with displacement sensors, such as accelerometers, and a photocell, which are then mounted to the pedestals or enclosure of the running part. Based on the vibrations detected, they calculate the part's unbalance. Many times these devices contain a spectrum analyzer so the part condition can be monitored without the use of a photocell and non-rotational vibration can be analyzed.", "Engineering,_Manufacturing": 0.9999063015, "qwen": "Yes"}
{"id": "17807412", "revid": "43290483", "url": "https://en.wikipedia.org/wiki?curid=17807412", "title": "Extrusion coating", "text": "Extrusion coating is the coating of a molten web of synthetic resin onto a substrate material. It is a versatile coating technique used for the economic application of various plastics, notably polyethylene, onto paperboard, corrugated fiberboard, paper, aluminium foils, cellulose, Non-wovens, or plastic films.\nProcess.\nCoating.\nThe actual process of extrusion coating involves extruding resin from a slot die at temperatures up to 320°C directly onto the moving web which may then passed through a nip consisting of a rubber covered pressure roller and a chrome plated cooling roll. The latter cools the molten film back into the solid state and also imparts the desired finish to the plastic surface. The web is normally run much faster than the speed at which the resin is extruded from the die, creating a coating thickness which is in proportion to the speed ratio and the slot gap.\nLaminating.\nExtrusion laminating is a similar process except that the extruded hot molten resin acts as the bonding medium to a second web of material.\nCo-extrusion.\nCo-extrusion is, again, a similar process but with two, or more, extruders coupled to a single die head in which the individually extruded melts are brought together and finally extruded as a multi-layer film.\nUses.\nThe market for extrusion coating includes a variety of end-use applications such as liquid packaging, photographic, flexible packaging, mill and industrial wrappings, transport packaging, sack linings, building, envelopes, medical/hygiene, and release base.", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "2534789", "revid": "21857263", "url": "https://en.wikipedia.org/wiki?curid=2534789", "title": "Label printer", "text": "A label printer is a computer printer that prints on self-adhesive label material and/or card-stock (tags). A label printer with built-in keyboard and display for stand-alone use (not connected to a separate computer) is often called a label maker. Label printers are different from ordinary printers because they need to have special feed mechanisms to handle rolled stock, or tear sheet (fanfold) stock. Common connectivity for label printers include RS-232 serial, Universal Serial Bus (USB), parallel, Ethernet and various kinds of wireless. Label printers have a wide variety of applications, including supply chain management, retail price marking, packaging labels, blood and laboratory specimen marking, and fixed assets management.\nMechanisms.\nLabel printers use a wide range of label materials, including paper and synthetic polymer (\"plastic\") materials. Several types of print mechanisms are also used, including laser and impact, but thermal printer mechanisms are perhaps the most common. \nThere are two common types of thermal printer.\nThere are three grades of ribbon for use with thermal transfer printers. Wax is the most popular with some smudge resistance, and is suitable for matte and semi-gloss paper labels. Wax/resin is smudge resistant, suitable for semi-gloss paper and some synthetic labels. Resin alone is scratch and chemical resistant, suitable for coated synthetic labels.\nWhen printing on continuous label stock, there is a tendency for the print location to shift slightly from label to label. To ensure registration of the print area with the target media, many label printers use a sensor that detects a gap, notch, line or perforation between labels. This allows the printer to adjust the intake of label stock so that the print aligns correctly with the media.\nTypes.\nLabel printer capabilities vary between home, corporate and industrial-oriented models.", "Engineering,_Manufacturing": 0.9978847504, "qwen": "Yes"}
{"id": "2535369", "revid": "39544904", "url": "https://en.wikipedia.org/wiki?curid=2535369", "title": "Continuous design", "text": "Evolutionary design, continuous design, evolutive design, or incremental design is directly related to any modular design application, in which components can be freely substituted to improve the design, modify performance, or change another feature at a later time.\nInformatics.\nIn particular, it applies (with the name continuous design) to software development. In this field it is a practice of creating and modifying the design of a system as it is developed, rather than purporting to specify the system completely before development starts (as in the waterfall model). Continuous design was popularized by extreme programming. Continuous design also uses test driven development and refactoring.\nMartin Fowler wrote a popular book called \"Refactoring\", as well as a popular article entitled \"Is Design Dead?\", that talked about continuous/evolutionary design. James Shore wrote an article in IEEE titled \"Continuous Design\".\nIndustrial design.\nModular design states that a product is made of subsystems that are joined together to create a full product. The above design model defined in electronics and evolved in industrial design into well consolidated industrial standards related to platform concept and its evolution.", "Engineering,_Manufacturing": 0.9971057177, "qwen": "Yes"}
{"id": "24676718", "revid": "41769454", "url": "https://en.wikipedia.org/wiki?curid=24676718", "title": "TMEIC", "text": "  is a joint venture between Toshiba and Mitsubishi Electric headquartered in Tokyo, Japan, specializing in industrial electric and automation systems for industrial plants. The company develops and produces power electronics apparatus, electric motors, drives, and uninterruptible power supplies. TMEIC has worldwide operations with approximately 2000 employees.\nHistory.\nTokyo Electric Company, the predecessor of Toshiba Corporation, was founded in 1896.\nMitsubishi Electric Corporation was founded in 1921.\nIn 1999, Toshiba and Mitsubishi Electric established TMA Electric Corporation (TMAE), a joint venture specializing in rotating machinery.\nIn 2000, Toshiba and General Electric Company formed Toshiba GE Automation Systems (TGAJ) operating in sales and engineering of industrial plant systems.\nToshiba and Mitsubishi Electric have decided to unify TMAE, TGAJ and their industrial systems division to form a joint venture named Toshiba Mitsubishi-Electric Industrial Systems Corporation (TMEIC).\nTMEIC started business on October 1, 2003.", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "24678329", "revid": "237572", "url": "https://en.wikipedia.org/wiki?curid=24678329", "title": "Facing (machining)", "text": "Facing in machining can be used in two different areas: facing on a milling machine and facing on a lathe. Facing on the milling machine involves various milling operations, but primarily face milling. On the lathe, facing is commonly used in turning and boring operations. Other operations remove material in ways similar to facing, for example, planing, shaping, and grinding, but these processes are not labeled by the term \"facing.\"\nFacing lathe operation.\nFacing on the lathe uses a facing tool to cut a flat surface perpendicular to the work piece's rotational axis. A facing tool is mounted into a tool holder that rests on the carriage of the lathe. The tool will then feed perpendicularly across the part's rotational axis as it spins in the jaws of the chuck. A user will have the option to hand feed the machine while facing, or use the power feed option. For a smoother surface, using the power feed option is optimal due to a constant feed rate. Facing will take the work piece down to its finished length very accurately. Depending on how much material needs to be taken off, a machinist can choose to take roughing or finishing cuts. Factors that affect the quality and effectiveness of facing operations on the lathe are speeds and feeds, material hardness, cutter size, and how the part is being clamped down.\nFace milling operation.\nFacing on a milling machine is the process of cutting a flat surface perpendicular to the axes of the milling cutter. This process removes the material by rotating the facing tool in the counterclockwise direction as the table feeds the work piece across the cutter. Face milling can be achieved with an end mill, but is often done with a face mill, shell mill or a fly cutter. Face milling can be done in both manual machining and CNC machining. To obtain a smoother surface finish it is best to let the machine feed the table. Newer manual milling machines and CNC machines will have this option, but older milling machines will not. When available, use the machine feed instead of manually feeding the part. This will provide an optimal surface finish due to the constant feed maintained by the mill. Hand feeding the table will allow human error into the process. Machinists also have the option to take roughing cuts and finish cuts. Factors that affect the quality and effectiveness of facing operations on the mill are speeds and feeds, material hardness, cutter size, and how the part is being clamped down.\nSpotfacing is the facing of spots (localized areas), such as the bearing surfaces on which bolt heads or washers will sit. ", "Engineering,_Manufacturing": 1.000007987, "qwen": "Yes"}
{"id": "662267", "revid": "45344735", "url": "https://en.wikipedia.org/wiki?curid=662267", "title": "Foundry model", "text": "The foundry model is a microelectronics engineering and manufacturing business model consisting of a semiconductor fabrication plant, or foundry, and an integrated circuit design operation, each belonging to separate companies or subsidiaries.\nIntegrated device manufacturers (IDMs) design and manufacture integrated circuits. Many companies, known as fabless semiconductor companies, only design devices; merchant or pure play foundries only manufacture devices for other companies, without designing them. Examples of IDMs are Intel, Samsung, and Texas Instruments,\nexamples of pure play foundries are GlobalFoundries, TSMC, and UMC, and examples of fabless companies are AMD, Nvidia, and Qualcomm.\nIntegrated circuit production facilities are expensive to build and maintain. Unless they can be kept at nearly full use, they will become a drain on the finances of the company that owns them. The foundry model uses two methods to avoid these costs: fabless companies avoid costs by not owning such facilities. Merchant foundries, on the other hand, find work from the worldwide pool of fabless companies, through careful scheduling, pricing, and contracting, keep their plants in full use.\nHistory.\nCompanies that both designed and produced the devices were originally responsible for manufacturing microelectronic devices. These manufacturers were involved in both the research and development of manufacturing processes and the research and development of microcircuit design.\nThe first pure play semiconductor company is the Taiwan Semiconductor Manufacturing Corporation, a spin-off of the government Industrial Technology Research Institute, which split its design and fabrication divisions in 1987, a model advocated for by Carver Mead in the U.S., but deemed too costly to pursue. The separation of design and fabrication became known as the foundry model, with fabless manufacturing outsourcing to semiconductor foundries.\nFabless semiconductor companies do not have any semiconductor fabrication capability; and contract production with a merchant foundry manufacturer. The fabless company concentrates on the research and development of an IC-product; the foundry concentrates on manufacturing and testing the physical product. If the foundry does not have any semiconductor design capability, it is a pure-play semiconductor foundry.\nAn absolute separation into fabless and foundry companies is not necessary. Some companies continue to exist that perform both operations and benefit from the close coupling of their skills. Some companies manufacture some of their own designs and contract out to have others manufactured or designed, in cases where they see value or seek special skills. The foundry model is a business vision that seeks to optimize productivity.\nMOSIS.\nThe very first merchant foundries were part of the MOSIS service. The MOSIS service gave limited production access to designers with limited means, such as students, university researchers, and engineers at small startups. The designer submitted designs, and these submissions were manufactured with the commercial company's extra capacity. Manufacturers could insert some wafers for a MOSIS design into a collection of their own wafers when a processing step was compatible with both operations. The commercial company (serving as foundry) was already running the process, so they were effectively being paid by MOSIS for something they were already doing. A factory with excess capacity during slow periods could also run MOSIS designs to avoid having expensive capital equipment stand idle.\nUnder-use of an expensive manufacturing plant could lead to the financial ruin of the owner, so selling surplus wafer capacity was a way to maximize the fab's use. Hence, economic factors created a climate where fab operators wanted to sell surplus wafer-manufacturing capacity and designers wanted to purchase manufacturing capacity rather than try to build it.\nAlthough MOSIS opened the doors to some fabless customers, earning additional revenue for the foundry and providing inexpensive service to the customer, running a business around MOSIS production was difficult. The merchant foundries sold wafer capacity on a surplus basis, as a secondary business activity. Services to the customers were secondary to the commercial business, with little guarantee of support. The choice of merchant dictated the design, development flow, and available techniques to the fabless customer. Merchant foundries might require proprietary and non-portable preparation steps. Foundries concerned with protecting what they considered trade secrets of their methodologies might only be willing to release data to designers after an onerous nondisclosure procedure.\nDedicated foundry.\nIn 1987, the world's first dedicated merchant foundry opened its doors: Taiwan Semiconductor Manufacturing Company (TSMC). The distinction of 'dedicated' is in reference to the typical merchant foundry of the era, whose primary business activity was building and selling of its own IC-products. The dedicated foundry offers several key advantages to its customers: first, it does not sell finished IC-products into the supply channel; thus a dedicated foundry will never compete directly with its fabless customers (obviating a common concern of fabless companies). Second, the dedicated foundry can scale production capacity to a customer's needs, offering low-quantity shuttle services in addition to full-scale production lines. Finally, the dedicated foundry offers a \"COT-flow\" (customer owned tooling) based on industry-standard EDA systems, whereas many IDM merchants required its customers to use proprietary (non-portable) development tools. The COT advantage gave the customer complete control over the design process, from concept to final design.\nFoundry sales leaders by year.\n2009–2007.\nAs of 2009, the top 17 semiconductor foundries were:\n2008–2006.\nAs of 2008, the top 18 pure-play semiconductor foundries were:\n2007–2005.\nAs of 2007, the top 14 semiconductor foundries include:\nFor ranking in worldwide:\n2004.\nAs of 2004, the top 10 pure-play semiconductor foundries were: \nFinancial and IP issues.\nLike all industries, the semiconductor industry faces upcoming challenges and obstacles.\nThe cost to stay on the leading edge has steadily increased with each generation of chips. The financial strain is being felt by both large merchant foundries and their fabless customers. The cost of a new foundry exceeds $1 billion. These costs must be passed on to customers. Many merchant foundries have entered into joint ventures with their competitors in an effort to split research and design expenditures and fab-maintenance expenses.\nChip design companies sometimes avoid other companies' patents simply by purchasing the products from a licensed foundry with broad cross-license agreements with the patent owner.\nStolen design data is also a concern; data is rarely directly copied, because blatant copies are easily identified by distinctive features in the chip,\nplaced there either for this purpose or as a byproduct of the design process. However, the data including any procedure, process system, method of operation or concept may be sold to a competitor, who may save months or years of tedious reverse engineering.", "Engineering,_Manufacturing": 0.999992609, "qwen": "Yes"}
{"id": "23630276", "revid": "11803565", "url": "https://en.wikipedia.org/wiki?curid=23630276", "title": "Wafer-level packaging", "text": "Wafer-level packaging (WLP) is a process where packaging components are attached to an integrated circuit (IC) \"before\" the wafer – on which the IC is fabricated – is diced. In WSP, the top and bottom layers of the packaging and the solder bumps are attached to the integrated circuits while they are still in the wafer. This process differs from a conventional process, in which the wafer is sliced into individual circuits (dice) before the packaging components are attached.\nWLP is essentially a true chip-scale package (CSP) technology, since the resulting package is practically of the same size as the die. Wafer-level packaging allows integration of wafer fab, packaging, test, and burn-in at wafer level in order to streamline the manufacturing process undergone by a device from silicon start to customer shipment. There is no single industry-standard method of wafer-level packaging at present.\nA major application area of WLPs are smartphones due to the size constraints. For example, the Apple iPhone 5 has at least eleven different WLPs, the Samsung Galaxy S3 has six WLPs and the HTC One X has seven. Functions provided WLPs in smartphones include sensors, power management, wireless, etc. In fact, it has recently been rumored that the iPhone 7 will use fan-out wafer-level packaging technology in order to achieve a thinner and lighter model.\nWafer-level chip scale packaging (WL-CSP) is the smallest package currently available on the market and is produced by OSAT (Outsourced Semiconductor Assembly and Test) companies, such as Advanced Semiconductor Engineering (ASE). A WL-CSP or WLCSP package is just a bare die with a redistribution layer (RDL, interposer or I/O pitch) to rearrange the pins or contacts on the die so that they can be big enough and have sufficient spacing so that they can be handled just like a ball grid array (BGA) package.\nThere are two kinds of wafer level packaging: fan-in and fan-out. Fan-in WLCSP packages have an interposer that is the same size as that of the die, where as fan-out WLCSP packages have an interposer that is larger than the die, similar to conventional BGA packages, the difference being that the interposer is built directly atop the die, instead of the die being attached to it and reflowed using the flip chip method. This is also true in fan-in WLSCP packages. In both cases, the die with its interposer may be covered in encapsulating material such as epoxy.\nIn February 2015, it was discovered that a WL-CSP chip in the Raspberry Pi 2 had issues with xenon flashes (or any other bright flashes of longwave light), inducing the photoelectric effect within the chip. Thus, careful consideration concerning exposure to extremely bright light will need to be given with wafer-level packaging.", "Engineering,_Manufacturing": 0.9999725819, "qwen": "Yes"}
{"id": "23649157", "revid": "1059654358", "url": "https://en.wikipedia.org/wiki?curid=23649157", "title": "Cell casting", "text": "Cell casting is a method used for creating poly(methyl methacrylate) (PMMA) sheets. Liquid monomer is poured between two flat sheets of toughened glass sealed with a rubber gasket and heated for polymerization. Because the glass sheets may contain surface scratches or sag during the process, this traditional method has some disadvantages: among other problems, the PMMA sheets may contain variations in thickness and surface defects. For many applications it has since been replaced by other methods for making PMMA such as extrusion, which gives uniform surface features. However, for applications where strength is critical cell casting techniques are still employed in conjunction with stretching, which produces a stronger overall material.\n\"Cell Casting - A process in which a casting liquid is poured between two plates, usually glass, that have a gasket between them to form a cell to contain the casting liquid; then the resin solidifies, usually through polymerization or crosslinking.\" - A. Brent Strong", "Engineering,_Manufacturing": 1.0000036955, "qwen": "Yes"}
{"id": "13233319", "revid": "563447", "url": "https://en.wikipedia.org/wiki?curid=13233319", "title": "Semi-solid metal casting", "text": "Semi-solid metal casting (SSM) is a near net shape variant of die casting. The process is used today with non-ferrous metals, such as aluminium, copper, and magnesium, but also can work with higher temperature alloys for which no currently suitable die materials are available. The process combines the advantages of casting and forging. The process is named after the fluid property thixotropy, which is the phenomenon that allows this process to work. Simply, thixotropic fluids flow when sheared, but thicken when standing. The potential for this type of process was first recognized in the early 1970s. There are three different processes: \"thixocasting\", \"rheocasting\", \"thixomolding\". \"SIMA\" refers to a specialized process to prepare aluminum alloys for thixocasting using hot and cold working .\nSSM is done at a temperature that puts the metal between its liquidus and solidus temperature. Ideally, the metal should be 30 to 65% solid. The semi-solid mixture must have a low viscosity to be usable, and to reach this low viscosity the material needs a globular primary surrounded by the liquid phase. The temperature range possible depends on the material and for aluminum alloys can be as much as 50 °C, but for narrow melting range copper alloys can be only several tenths of a degree.\nSemi-solid casting is typically used for high-end applications. For aluminum alloys, typical parts include structural medical and aerospace parts, pressure containing parts, defense parts, engine mounts, air manifold sensor harnesses, engine blocks, and oil pump filter housings.\nProcesses.\nThere are a number of different techniques to produce semi-solid castings. For aluminum alloys the more common processes are \"thixocasting\" and \"rheocasting\".\nWith magnesium alloys, the most common process is \"molding\".\nThixocasting.\nThixocasting utilizes a pre-cast billet with a non-dendritic microstructure that is normally produced by vigorously stirring the melt as the bar is being cast. Induction heating is normally used to re-heat the billets to the semi-solid temperature range, and die casting machines are used to inject the semi-solid material into hardened steel dies. Thixocasting is being performed commercially in North America, Europe and Asia. Thixocasting has the ability to produce extremely high quality components due to the product consistency that results from using pre-cast billet that is manufactured under the same ideal continuous processing conditions that are employed to make forging or rolling stock. The main disadvantage is that it is expensive due to the special billets that must be used, although facilities with in house magnetohydrodynamic continuous casting capabilities can recycle 100% of in-house returns. Other disadvantages include a limited number of alloys, and for facilities without in-house magnetohydrodynamic casting capability scrap cannot be directly reused.\nRheocasting.\nUnlike thixocasting, which re-heats a billet, rheocasting develops the semi-solid slurry from the molten metal produced in a typical die casting furnace. This is a big advantage over thixocasting because it results in less expensive feedstock, in the form of typical die casting alloys, and allows for direct recycling. However, rheocasting also poses process control issues such that after an initial surge of activity, very little material is processed via rheocasting.\nThixomolding.\nFor magnesium alloys, thixomolding uses a machine similar to injection molding. In a single step process, room temperature magnesium alloy chips are fed into the back end of a heated barrel through a volumetric feeder. The barrel is maintained under an argon atmosphere to prevent oxidation of the magnesium chips. A screw conveyor located inside the barrel feeds the magnesium chips forward as they are heated into the semi-solid temperature range. The screw rotation provides the necessary shearing force to generate the globular structure needed for semi-solid casting. Once enough slurry has accumulated, the screw moves forward to inject the slurry into a steel die.\nStrain-induced melt-activated (SIMA).\nIn the SIMA method the material is first heated to the SMM temperature. As it nears the solidus temperature the grains recrystallize to form a fine grain structure. After the solidus temperature is passed the grain boundaries melt to form the SSM microstructure. For this method to work the material should be extruded or cold rolled in the half-hard tempered state. This method is limited in size to bar diameters smaller than ; because of this only smaller parts can be cast.\nAdvantages.\nThe advantages of semi-solid casting are as follows:\nHigh consolidation pressures are used to produce high integrity parts, and temperatures required to die-cast semi-solid metal are lower than normal casting; conventional tool steel materials are typically used in production applications. The lack of suitable high temperature die materials limits the casting of high melting point metals, such as tool steel and stellite, only to experimental applications. Other advantages include ease of automation, consistency, production rates equal to or better than die casting rates, no air entrapment, low shrinkage rates, and uniform microstructure.\nDisadvantages.\nProduction facilities do require a higher degree of control over process conditions, but standard die casting machines are very suitable for production albeit with higher final injection pressures and lower injection velocities.\nWhile selling thixocast scrap can be costly, facilities with on-site magneto-hydrodynamic continuous casting capabilities are able to completely recycle all in-house material returns.\nBecause thixotropy (semi-solid state) is a middle state in physical or rheological sense, this process is relatively insensitive to ambient temperature since small heat losses cause only minor changes in fraction solid.", "Engineering,_Manufacturing": 0.9998332858, "qwen": "Yes"}
{"id": "69940217", "revid": "117878", "url": "https://en.wikipedia.org/wiki?curid=69940217", "title": "Saab Aeronáutica Montagens", "text": "Saab Aeronáutica Montagens SA is a Brazilian aeronautical company which has operated since 2018 as a subsidiary company of the Sweden aerospace conglomerate Saab AB. The Brazilian aerospace engineering company, Akaer Engenharia SA, has a shareholding in this company.\nSaab Aeronáutica Montagens is producing empennage, air brakes, the wingbox, the rear fuselage, and the forward fuselage for their mainline product: Saab JAS 39 Gripen. The manufacturer hopes that in the future this assembly line will be used to manufacture these parts for aircraft that may be sold to other countries.", "Engineering,_Manufacturing": 0.9998991489, "qwen": "Yes"}
{"id": "24257054", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=24257054", "title": "Confirmed line item performance", "text": "The Confirmed Line Item Performance (CLIP) is one of the diagnostic metrics for perfect order fulfillment which defines the supply chain delivery reliability measurement between facilities within a supply chain.\nThose facilities may belong to one company or span over several companies. CLIP is an analog measurement taking the portion of fulfillment into account using customer commit date as reference date. This intends a usage within a supply chain part with a fixed-period demand pattern (e.g. daily or weekly) and a permanent material flow (e.g. between production and distribution center), which is later on again split to be sent to different customers and locations.\nDefinition.\nCLIP shows the relation between the sum of the deliveries and excess deliveries compared to the sum of orders and actual backlog by part number for the considered period of time. In aggregation of all part numbers (identifier for production control, calculation, shipment and other purposes products), it shows the status of order fulfillment. Excess delivery (pre- plus over-delivery) for one product (specified by its part number) does not compensate for the backlog of another product.\nThe definitions for backlog, pre-delivery, over-delivery and excess delivery for a single product are as follows: \nTo determine the confirmed line item performance two \"virtual\" quantities are introduced: the virtually committed order and the virtual delivery. The virtually committed order for a product p consists of the actual order for the considered delivery week (DW) plus any backlog of this product accumulated up to that week.\nThe virtual delivery for a product consists of the actually delivered chips within the considered delivery week plus any excess deliveries of this product accumulated up to that week.\nThe confirmed line item performance of one product p for a delivery week is calculated as the ratio of the virtual delivery to the virtually committed order. If there are more chips delivered than ordered, the CLIP of the respective product is 100%.\nThe CLIP of the whole site is calculated as the average CLIP of all products with a virtually committed order. Each product is counted separately (by part number). There is no weighting by volume applied.\nAggregation.\nCLIP is being measured for every part number. The CLIP value of a certain “bundle“ (location, PL, Segment etc.) of part numbers is calculated by averaging the CLIP values of the individual part number in that “bundle“. Each part number in an aggregation (“bundle”) is counted as 1, irrespective of how big the volume of production for that part number is.\nThe lateness compared to the confirmed date is taken into account. In every period p the backlog of previous periods is not fulfilled the CLIP performance is worsened signaling the receiver an open demand.", "Engineering,_Manufacturing": 0.997627914, "qwen": "Yes"}
{"id": "24271456", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=24271456", "title": "Ultrasonic consolidation", "text": "Ultrasonic Consolidation (UC) or Ultrasonic Additive Manufacturing (UAM) is a low temperature additive manufacturing or 3D printing technique for metals.\nThe process works by scrubbing metal foils together with ultrasonic vibrations under pressure in a continuous fashion, i.e., sheet lamination classification in additive manufacturing. Melting is not the formation mechanism. Instead, metals are joined in the solid-state via disruption of surface oxide films between the metals, i.e. ultrasonic metal welding mechanisms. CNC contour milling is used interchangeably with the additive stage of the process to introduce internal features and add detail to the metal part. UAM has the ability to join multiple metal types together, i.e., dissimilar metal joining, with no or minimal intermetallic formation and allows the embedment of temperature sensitive materials at relatively low temperature—typically less than 50% of the metal matrix melting temperature. \nHistory.\nThe Ultrasonic Consolidation or Ultrasonic Additive Manufacturing process was invented and patented by Dawn White. In 1999, White founded Solidica Inc. to sell commercial UAM equipment—Form-ation machine suite. Near 2007, the Edison Welding Institute (EWI) and Solidica began a collaboration to re-design the weld tooling to remedy bond quality limitations and to expand the weldable metals of the process—so called very high power UAM. In 2011, Fabrisonic LLC was formed to commercialize the improved UAM process—SonicLayer machine suite. A SonicLayer 4000 system was simultaneously deployed at the Ohio State University.\nProcess.\nAs with most other additive manufacturing processes UC creates objects directly from a CAD model of the required object. The file is then \"sliced\" into layers which results in the production of a .STL file that can be used by the UC machine to build the required object, layer by layer.\nThe general manufacturing process is:\nMechanism of the metallurgical bond formation between foils can be explained by microscopic deformation of micro-asperities on the top foil. The sonotrode surface is usually textured so as to facilitate the grip of the top foil subjected to vibrations. The resultant rough imprint on the top foil surface affects bonding of the subsequent layer. The contact area between the upper and lower foils expands when the micro-asperities are crushed by the ultrasonic oscillations.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "24283775", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=24283775", "title": "Motor-CAD", "text": "Motor-CAD is an Electromagnetic and Thermal analysis package for electric motors and generators, developed and sold by Motor Design Ltd. It was initially released in 1999.\nModules are available for brushless permanent magnet motors (BPM), outer rotor BPM motors, induction motors, permanent magnet dc machines, switched reluctance motors, synchronous machines and claw pole machines.\nAn integrated ultra fast finite element module (EMag) provides accurate electromagnetic and electrical performance predictions.\nThe thermal module (Therm) combines lumped circuit and finite element thermal calculations for optimising the cooling system of the machine. \nCooling methods modelled include natural convection (Totally enclosed non ventilated - TENV), forced convection (Totally enclosed fan cooled - TEFC), through ventilation, water jackets, submersible, wet rotor and wet stator, spray cooling, radiation and conduction.\nA wide range of housing types can be modelled.\nThe Lab module works with the EMag and Therm modules to help develop new design concepts. It provides efficiency mapping and duty cycle / drive cycle transient outputs within a few minutes.\nThermal analysis of electric machines is regarded as a more challenging area of analysis than electromagnetic analysis in the construction of the model and the accuracy achievable.\nThermal analysis of electrical machines is becoming ever more important due to the increasing drive for energy efficiency and compact design machines. This is particularly true for the aerospace and automotive sectors where size, weight and efficiency are driving the design of machines.\nThe design approach often taken is to consider both electromagnetic and thermal aspects of a machines design at the early stages in machine design, where Motor-CAD allows this to be done.\nOther possible thermal modelling techniques include computational fluid dynamics. Motor-CAD has been shown to give results with a similar accuracy in a fraction of the time.", "Engineering,_Manufacturing": 1.0000069141, "qwen": "Yes"}
{"id": "41298269", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=41298269", "title": "FSI International", "text": "FSI International, Inc. (FSI) is an American manufacturing company based in Chaska, Minnesota, that supplies processing equipment used to manufacture microelectronics, including semiconductor devices.\nHistory.\nThe company's history began with the establishment of Fluoroware, Inc. in 1966, a company that made fixtures to hold the silicon wafers in place during the various processes involved in producing semiconductor devices. When asked to design a drying apparatus, the principals of Fluoroware agreed to do so and established FSI International in 1973 to market this new product. \nThe company's offerings expanded to meet the market need for equipment used in the fabrication of microelectronics. In the 1990s, the company relocated from its original facility overlooking Hazeltine Lake to a larger site nearby. \nIn 1999, FSI International announced an agreement to acquire YieldUP International Corp. In October 2012, Tokyo Electron acquired FSI International, Inc. and renamed the division TEL FSI. \nProducts.\nFSI International supplied surface conditioning technology solutions, using wet, cryogenic and other chemistry techniques to clean, strip or etch the surfaces of silicon wafers. The company also engaged in microlithography systems for photoresist, light-sensitive, and etch-resistant films. The company provides upgrade, replacement and other support services.\nThe five main series of equipment produced by the company are: ZETA, MERCURY, ORION, ANTARES, and POLARIS, and in earlier years, the company also produced the SATURN and NEPTUNE processing systems. Some of the products of the company are spray cleaning systems, single wafer cleaning systems, cryogenic processing systems, and immersion cleaning systems.", "Engineering,_Manufacturing": 0.995234251, "qwen": "Yes"}
{"id": "41311958", "revid": "1163957899", "url": "https://en.wikipedia.org/wiki?curid=41311958", "title": "Vericut", "text": "Vericut (publicly capitalized VERICUT), is a software program used for simulating CNC machining. It is used to simulate tool motion and the material removal process, detecting errors or areas of inefficiency in NC programs. It was developed by CGTech Inc. and first released in 1988.\nHistory.\nVericut was designed by CGTech Inc. in 1988. The software was first developed to run in Unix workstations and was later ported to Windows. Since its initial launch, Vericut has been installed and is used by Fortune 500 and other notable companies including Boeing, Airbus, General Motors, and Israel Aircraft Industries As of 2009, Vericut has been used by more than 2000 companies worldwide. In 2011, CGTech was ranked as the largest independent NC verification and simulation software provider based on revenue, with over 9,000 installed seats.\nFeatures.\nVericut is standalone software but also integrates with CAD, CAM, and PLM systems including CATIA, Siemens NX, PowerMILL, EdgeCAM, Mastercam and Hypermill. It uses a three-axis through five-axis simulation motion to simulate milling and drilling operations. The simulation is displayed on a graphics screen as a solid 3D model of the raw stock, simulating the programmed cutting motions and then displaying the finished part.\nMachine tool simulation.\nVericut software is customizable and includes a selection of machine tools. Machine models can also be built from scratch, using a CAD system or by defining such in the software. It contains a component tree to manage the kinematics of a machine. Vericut simulates machine tools in their entirety as they would appear in a shop and shows the removal of material at the workpiece level. It also simulates NC machine controls and automatically checks for collisions and over travel of machine tools to reduce the probability of a machine crash.\nThe machine simulation feature detects all machine components for near-misses and collisions. Near miss zones can be set up by users around components to check for close calls and over-travel errors. Machine movements are simulated in review mode while stepping or playing backwards.\nNC program optimization.\nVericut has NC program optimizing capabilities. It automatically determines the safe feed rate for each cut based on programmed feed rates, reducing cycling time. The optimization is said to reduce the amount of scrapped parts, broken tools, and cutter deflection.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "41318612", "revid": "12580852", "url": "https://en.wikipedia.org/wiki?curid=41318612", "title": "TO-126", "text": "TO-126 is a type of semiconductor package for devices with three pins, such as transistors. The package is rectangular with a hole in the middle to allow for easy mounting to a board or a heat sink. On one side of the package typically a metal sheet is exposed, with the transistor die bonded to the other side of the metal sheet inside the package. This allows for an efficient heat transfer from the transistor die to an external heat sink but also implies that the metal sheet is electrically connected to the die (for a bipolar junction transistor usually the collector is connected to this metal sheet).\nHistory and origin.\nThe JEDEC TO-126 descriptor is derived from the original full name for the package: Transistor Outline Package, Case Style 126. In the updated JEDEC outline system, the package is numbered as TO-225AA.\nSTMicroelectronics refers to this package style as SOT-32.", "Engineering,_Manufacturing": 0.9981577396, "qwen": "Yes"}
{"id": "1407684", "revid": "38427", "url": "https://en.wikipedia.org/wiki?curid=1407684", "title": "Reflow soldering", "text": "Reflow soldering is a process in which a solder paste (a sticky mixture of powdered solder and flux) is used to temporarily attach one or thousands of tiny electrical components to their contact pads, after which the entire assembly is subjected to controlled heat. The solder paste reflows in a molten state, creating permanent solder joints. Heating may be accomplished by passing the assembly through a reflow oven, under an infrared lamp, or (unconventionally) by soldering individual joints with a desoldering hot air pencil.\nReflow soldering with long industrial convection ovens is the preferred method of soldering surface mount technology components or SMT to a printed circuit board or PCB. Each segment of the oven has a regulated temperature, according to the specific thermal requirements of each assembly. Reflow ovens meant specifically for the soldering of surface mount components may also be used for through-hole components by filling the holes with solder paste and inserting the component leads through the paste. Wave soldering however, has been the common method of soldering multi-leaded through-hole components onto a circuit board designed for surface-mount components.\nWhen used on boards containing a mix of SMT and plated through-hole (PTH) components, through-hole reflow, when achievable by specifically modified paste stencils, may allow for the wave soldering step to be eliminated from the assembly process, potentially reducing assembly costs. While this may be said of lead-tin solder pastes used previously, lead-free solder alloys such as SAC present a challenge in terms of the limits of oven temperature profile adjustment and requirements of specialized through-hole components that must be hand soldered with solder wire or cannot reasonably withstand the high temperatures directed at circuit boards as they travel on the conveyor of the reflow oven. The reflow soldering of through-hole components using solder paste in a convection oven process is called intrusive soldering.\nThe goal of the reflow process is for the solder paste to reach the eutectic temperature at which the particular solder alloy undergoes a phase change to a liquid or molten state. At this specific temperature range, the molten alloy demonstrates properties of adhesion. Molten solder alloy behaves much as water, with properties of cohesion and adhesion. With sufficient flux, in the state of liquidus, molten solder alloys will exhibit a characteristic called \"wetting.\"\nWetting is a property of the alloy when within its specific eutectic temperature range. Wetting is a necessary condition for the formation of solder joints that meet the criteria as \"acceptable\" or \"target\" conditions, while \"non-conforming\" is considered defective according to IPC.\nThe reflow oven temperature profile is suited for characteristics of a particular circuit board assembly, the size and depth of the ground plane layer within the board, the number of layers within the board, the number and size of the components, for example. The temperature profile for a particular circuit board will allow for reflow of solder onto the adjoining surfaces, without overheating and damaging the electrical components beyond their temperature tolerance. In the conventional reflow soldering process, there are usually four stages, called \"zones\", each having a distinct thermal profile: \"preheat\", \"thermal soak\" (often shortened to just \"soak\"), \"reflow\", and \"cooling\".\nPreheat zone.\nPreheat is the first stage of the reflow process. During this reflow phase, the entire board assembly climbs towards a target soak or dwell temperature. The main goal of the preheat phase is to get the entire assembly safely and consistently to a soak or pre-reflow temperature. Preheat is also an opportunity for volatile solvents in the solder paste to outgas. For paste solvents to be properly expelled and the assembly to safely reach pre-reflow temperatures the PCB must be heated in a consistent, linear manner. An important metric for the first phase of the reflow process is the temperature slope rate or rise vs time. This is often measured in degrees Celsius per second, °C/s. Many variables factor into a manufacturer's target slope rate. These include: target processing time, solder paste volatility, and component considerations. It is important to account for all these process variables, but in most cases sensitive component considerations are paramount.\n“Many components will crack if their temperature is changed too quickly. The maximum rate of thermal change that the most sensitive components can withstand becomes the maximum allowable slope”. However, if thermally sensitive components are not in use and maximizing throughput is of great concern, aggressive slope rates may be tailored to improve processing time. For this reason, many manufacturers push these slope rates up to the maximum common allowable rate of 3.0 °C/s. Conversely, if a solder paste containing particularly strong solvents is being used, heating the assembly too fast can easily create an out of control process. As the volatile solvents outgas they may splatter solder off the pads and onto the board. Solder-balling is the main concern of violent outgassing during the preheat phase. Once a board has been ramped up to temperature in the preheat phase it is time to enter the soak or pre-reflow phase.\nThermal soak zone.\nThe second section, thermal soak, is typically a 60 to 120 second exposure for removal of solder paste volatiles and activation of the fluxes, where the flux components begin oxide reduction on component leads and pads. Too high a temperature can lead to solder spattering or balling as well as oxidation of the paste, the attachment pads and the component terminations. Similarly, fluxes may not fully activate if the temperature is too low. At the end of the soak zone a thermal equilibrium of the entire assembly is desired just before the reflow zone. A soak profile is suggested to decrease any delta T between components of varying sizes or if the PCB assembly is very large. A soak profile is also recommended to diminish voiding in area array type packages.\nReflow zone.\nThe third section, the reflow zone, is also referred to as the “time above reflow” or “temperature above liquidus” (TAL), and is the part of the process where the maximum temperature is reached. An important consideration is peak temperature, which is the maximum allowable temperature of the entire process. A common peak temperature is 20–40 °C above liquidus. This limit is determined by the component on the assembly with the lowest tolerance for high temperatures (the component most susceptible to thermal damage). A standard guideline is to subtract 5 °C from the maximum temperature that the most vulnerable component can sustain to arrive at the maximum temperature for process. It is important to monitor the process temperature to keep it from exceeding this limit. Additionally, high temperatures (beyond 260 °C) may cause damage to the internal dies of SMT components as well as foster intermetallic growth. Conversely, a temperature that isn’t hot enough may prevent the paste from reflowing adequately.\nTime above liquidus (TAL), or time above reflow, measures how long the solder is a liquid. The flux reduces surface tension at the juncture of the metals to accomplish metallurgical bonding, allowing the individual solder powder spheres to combine. If the profile time exceeds the manufacturer’s specification, the result may be premature flux activation or consumption, effectively “drying” the paste before formation of the solder joint. An insufficient time/temperature relationship causes a decrease in the flux’s cleaning action, resulting in poor wetting, inadequate removal of the solvent and flux, and possibly defective solder joints. Experts usually recommend the shortest TAL possible, however, most pastes specify a minimum TAL of 30 seconds, although there appears to be no clear reason for that specific time. One possibility is that there are places on the PCB that are not measured during profiling, and therefore, setting the minimum allowable time to 30 seconds reduces the chances of an unmeasured area not reflowing. A high minimum reflow time also provides a margin of safety against oven temperature changes. The wetting time ideally stays below 60 seconds above liquidus. Additional time above liquidus may cause excessive intermetallic growth, which can lead to joint brittleness. The board and components may also be damaged at extended temperature over liquidus, and most components have a well-defined time limit for how long they may be exposed to temperatures over a given maximum. Too little time above liquidus may trap solvents and flux and create the potential for cold or dull joints as well as solder voids.\nCooling zone.\nThe last zone is a cooling zone to gradually cool the processed board and solidify the solder joints. Proper cooling inhibits excess intermetallic formation or thermal shock to the components. Typical temperatures in the cooling zone range from 30–110 °C (86–212 °F). A fast cooling rate is chosen to create a fine grain structure that is most mechanically sound. Unlike the maximum ramp-up rate, the ramp–down rate is often ignored. The ramp rate is less critical above certain temperatures, however, the maximum allowable slope for any component should apply whether the component is heating up or cooling down. A cooling rate of 4 °C/s is commonly suggested. It is a parameter to consider when analyzing process results.\nEtymology.\nThe term \"reflow\" is used to refer to the temperature above which a solid mass of solder alloy is certain to melt (as opposed to merely soften). If cooled below this temperature, the solder will not flow. Warmed above it once more, the solder will flow again—hence \"re-flow\".\nModern circuit assembly techniques that use reflow soldering do not necessarily allow the solder to flow more than once. They guarantee that the granulated solder contained in the solder paste surpasses the reflow temperature of the solder involved.\nThermal profiling.\nThermal profiling is the act of measuring several points on a circuit board to determine the thermal excursion it takes through the soldering process.\nIn the electronics manufacturing industry, SPC (Statistical Process Control) helps determine if the process is in control, measured against the reflow parameters defined by the soldering technologies and component requirements.\nModern software tools allow a profile to be captured, then automatically optimized using a mathematical simulation, which greatly reduces the time needed to establish optimal settings for the process.\nReferences.\nhttp://www.idc-online.com/technical_references/pdfs/electronic_engineering/Electronics_Manufacture_Intrusive_Reflow.pdf", "Engineering,_Manufacturing": 1.0000083447, "qwen": "Yes"}
{"id": "73901625", "revid": "41977899", "url": "https://en.wikipedia.org/wiki?curid=73901625", "title": "Results of the 1990 Ontario general election by riding", "text": "The following are the results by riding (electoral district) of the 1990 Ontario general election, that was held on September 6, 1990.\nConstituency results.\nOttawa-Carleton.\nTotal votes: 38,074\nTotal votes: 35,376\nTotal votes: 32,328\nTotal votes: 30,446\nOttawa East \nTotal votes: 26,218\nTotal votes: 29,695\nTotal votes: 30,185\nTotal votes: 33,422\nEastern Ontario.\nTotal votes: 27 347\nTotal votes: 29,174\nTotal votes: 28 282\nRonald Gerow (CoR) 1128 (4.0%)\nTotal votes: 26 807\nTotal votes: 34 330\nTotal votes: 39 833\nTotal votes: 27 752\nTotal votes: 29 691\nTotal votes: 30 198\nTotal votes: 29 082\nCentral Ontario.\nTotal votes: 30,429\nTotal votes: 31,447\nTotal votes: 38,056\nTotal votes: 33 031\nTotal votes: 35 740\nTotal votes: 41,888\nTotal votes: 41 572\nTotal votes: 37 398\nTotal votes: 32 089\nTotal votes: 34 889\nDurham & York Region.\nTotal votes: 35,096\nTotal votes: 33 476\nTotal votes: 43,678\nTotal votes: 36 284\nTotal votes: 51 221\nTotal votes: 27 173 \nTotal votes: 61 562\nTotal votes: 33,437\nScarborough.\nTotal votes: 30 118\nTotal votes: 27,262\nTotal votes: 32 915\nTotal votes: 29 119\nTotal votes: 30 056\nTotal votes: 28 027\nNorth York & East York.\nTotal votes: 28,483\nTotal votes: 23 755\nTotal votes: 26 364\nTotal votes: 25 454\nTotal votes: 33,947\nTotal votes: 27,725\nTotal votes: 29 848\nTotal votes: 29 207\nTotal votes: 20 059\nToronto.\nTotal votes: 24 645\nTotal votes: 19 548\nTotal votes: 33 451\nTotal votes: 23 806\nTotal votes: 25 337\nTotal votes: 17 417\nTotal votes: 22 729\nTotal votes: 29 956\nTotal votes: 29 706\nEtobicoke & York.\nTotal votes: 35 178\nTotal votes: 31 660\nTotal votes: 26 270\nTotal votes: 33 810\nTotal votes: 21 384\nTotal votes: 24 949\nBrampton, Mississauga & Halton.\nTotal votes: 33,462\nTotal votes: 39 985\nTotal votes: 32 520\nTotal votes: 38 523\nTotal votes: 27,503\nTotal votes: 31 684\nTotal votes: 33 442\nTotal votes: 32 652\nTotal votes: 47 584\nTotal votes: 31,304\nHamilton-Wentworth & Niagara.\nTotal votes: 25 358\nTotal votes: 28 336\nTotal votes: 37 629\nTotal votes: 32 777\nTotal votes: 34,141\nTotal votes: 29 939\nTotal votes: 23 972\nTotal votes: 29 835\nTotal votes: 27,478\nTotal votes: 32 202\nTotal votes: 34 111\nTotal votes: 33 692\nMidwestern Ontario.\nTotal votes: 36 474\nTotal votes: 28 785\nTotal votes: 36 176\nTotal votes: 39 701\nTotal votes: 29 070\nTotal votes: 33 640\nTotal votes: 36 537\nTotal votes: 36 195\nTotal votes: 36 504\nTotal votes: 31 802\nTotal votes: 38 883\nTotal votes: 30 646\nSouthwestern Ontario.\nTotal votes: 31,138\nTotal votes: 34 047\nTotal votes: 30 116\nTotal votes: 29 358\nTotal votes: 27,675\nTotal votes: 34 765\nTotal votes: 43 770\nTotal votes: 41 115\nTotal votes: 38 382\nTotal votes: 29 586\nTotal votes: 29 769\nTotal votes: 29 298\nTotal votes: 28 807\nNortheastern Ontario.\nTotal votes: 14 017\nTotal votes: 15 339\nTotal votes: 16 354\nTotal votes: 24 069\nTotal votes: 16 955\nTotal votes: 33 741\nTotal votes: 23 020\nTotal votes: 38 713\nTotal votes: 32,530\nTotal votes: 30 232\nTotal votes: 19,779\nNorthwestern Ontario.\nTotal votes: 26,551\nTotal votes: 20 106\nTotal votes: 12,785\nTotal votes: 27 798\nTotal votes: 12 751", "Engineering,_Manufacturing": 0.9999375343, "qwen": "Yes"}
{"id": "41512317", "revid": "5663757", "url": "https://en.wikipedia.org/wiki?curid=41512317", "title": "Cold foil printing", "text": "Cold foil printing, also known as cold foil stamping, is a modern method of printing metallic foil on a substrate in order to enhance the aesthetic of the final product. Cold foil printing can be done two ways: the older dry lamination process common in the offset printing industry, or the newer, more versatile wet lamination process, which is dominant in the flexo label industry.\nHow it works.\nCold foil dry lamination.\nUsing a standard printing plate, an image is printed onto a substrate with the use of an ultraviolet-curable cold foil adhesive. An ultraviolet dryer then cures the adhesive, which becomes tacky. Foil spools from an unwind and is nipped to a substrate. Foil sticks to the tacky adhesive on the substrate, and an image with a bright foil surface is created. Foil that does not adhere to the adhesive remains on a thin polyester liner, and waste is directed to a rewind spool. Because the adhesive is applied on press like a conventional ink, no expensive stamping die has to be created.\nOnce printed, the surface of cold foil images may be varnished, laminated, or encapsulated in order to provide a hard-wearing, durable surface.\nSubstrates.\nSome printing substrates are unsuitable for cold foil transfer. The best results are obtained on glossy coated papers and papers with a smooth surface. Weights from about 80 to 500 g/m^2 are possible.\nBenefits.\nThe process does not require stamping tools, but instead uses printing plates, which are cheaper and can be made in a few hours. In contrast, delivery time for an engraved or etched stamping tool can be up to two weeks. More importantly for the designer, gradients and halftone images can be introduced.\nHistory.\nHot foil stamping.\nCold foil evolved from hot foil stamping. Hot foil stamping is mostly used offline when foil is required on a preprinted substrate, such as in the manufacture of greeting cards and special occasion ribbons. Hot foil is economical but very slow. The types of graphics that can be applied are usually limited to text and bold images. Hot foil is not usable with heat-sensitive substrates such as polyethylene, vinyl, or shrink film.\nCold foil evolution.\nCold foil takes the idea of hot foil stamping and makes it more convenient and cost-effective. The cold foil functions like an additional ink and is actually a UV-curable, very fast lamination adhesive and can be bonded in-line in a single run using a printing plate for either flexographic web printing or offset sheet-fed printing. It can be applied precisely with high resolution, even for fine structures such as raster gradients and thin lines. Typeface is legible from about 5 points upwards and has excellent edge definition. Cold foil printing needs smooth surface substrates for excellent image quality.\nCold foil indexing.\nAs the cold foil market evolves, major players in the printing industry are finding ways to make the process even more cost-effective. By indexing cold foil, printers can reduce foil waste, reduce their presses' downtime, and in turn maximize their presses' efficiency.\nUses.\nCold foil is most commonly used on products that call for a strong \"shelf appeal\", such as household consumables, cigarette cartons, wine labels, and cosmetic packaging. It provides a luxurious metallic look on higher added-value label applications.", "Engineering,_Manufacturing": 0.9925127029, "qwen": "Yes"}
{"id": "41533088", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=41533088", "title": "Assemble-to-order system", "text": "In applied probability, an assemble-to-order system is a model of a warehouse operating a build to order policy where products are assembled from components only once an order has been made.\nThe time to assemble a product from components is negligible, but the time to create components is significant (for example, they must be ordered from a supplier).\nResearch typically focuses on finding good policies for inventory levels and on the impact of different configurations (such as having more shared parts). The special case of only one product is an assembly system, the case of just once component is a distribution system.\nModel definition.\nSingle period model.\nThis case is a generalisation of the newsvendor model (which has only one component and one product). The problem involves three stages and we give one formation of the problem below\nWe use the following notation\nIn the final stage when demands are known the optimization problem faced is to \nand we can therefore write the optimization problem at the first stage as\nwith x0 representing the starting inventory vector and \"c\" the cost function for acquiring the components.\nContinuous time.\nIn continuous time orders for products arrive according to a Poisson process and the time required to produce components are independent and identically distributed for each component. Two problems typically studied in this system are to minimize the expected backlog of orders subject to a constraint on the component inventory, and to minimize the expected component inventory subject to constraints on the rate at which orders must be completed.", "Engineering,_Manufacturing": 0.9971784949, "qwen": "Yes"}
{"id": "26942963", "revid": "46294397", "url": "https://en.wikipedia.org/wiki?curid=26942963", "title": "Welding joint", "text": "In metalworking, a welding joint is a point or edge where two or more pieces of metal or plastic are joined together. They are formed by welding two or more workpieces according to a particular geometry. There are five types of joints referred to by the American Welding Society: butt, corner, edge, lap, and tee. These configurations may have various configurations at the joint where actual welding can occur.\nButt welds.\nButt welds are welds where two pieces of metal to be joined are in the same plane. These welds require only some preparation and are used with thin sheet metals that can be welded with a single pass. Common issues that can weaken a butt weld are the entrapment of slag, excessive porosity, or cracking. For strong welds, the goal is to use the least amount of welding material possible. \nButt welds are prevalent in automated welding processes, such as submerged-arc welding, due to their relative ease of preparation. When metals are welded without human guidance, there is no operator to adjust non-ideal joint preparation. Because of this necessity, butt welds can be utilized for their simplistic design to be fed through automated welding machines efficiently.\nTypes.\nThere are many types of butt welds, but all fall within one of these categories: single-welded butt joints, double-welded butt joint, and open or closed butt joints. A single welded butt joint is the name for a joint that has only been welded from one side. A double-welded butt joint is created when the weld has been welded from both sides. With double welding, the depths of each weld can vary slightly. A closed weld is a type of joint in which the two pieces that will be joined are touching during the welding process. An open weld is the joint type where the two pieces have a small gap in between them during the welding process.\nSquare butt joints.\nThe square groove is a butt welding joint with the two pieces being flat and parallel to each other. This joint is simple to prepare, economical to use, and provides satisfactory strength but is limited by joint thickness. The closed square butt weld is a type of square-groove joint with no spacing in between the pieces. This joint type is common with gas and arc welding. \nFor thicker joints, the edge of each member of the joint must be prepared to a particular geometry to provide accessibility for welding and to ensure the desired weld soundness and strength. The opening or gap at the root of the joint and the included angle of the groove should be selected to require the least weld metal necessary to give needed access and meet strength requirements. Only metal up to 4.5mm thick is usually used for square butt joints.\nV-joints.\nSingle V welds are similar to a bevel joint, but instead of only one side having the bevelled edge, both sides of the weld joint are beveled. In thick metals, and when welding can be performed from both sides of the work piece, a double-V joint is used. When welding thicker metals, a double-V joint requires less filler material because there are two narrower V-joints compared to a wider single-V joint. Also the double-V joint helps compensate for warping forces. With a single-V joint, stress tends to warp the piece in one direction when the V-joint is filled, but with a double-V-joint, there are welds on both sides of the material, having opposing stresses, straightening the material.\nJ-joints.\nSingle-J butt welds are when one piece of the weld is shaped like a \"J\" that easily accepts filler material and the other piece is square. A J-groove is formed either with special cutting machinery or by grinding the joint edge into the form of a J. Although a J-groove is more difficult and costly to prepare than a V-groove, a single J-groove on metal between a half an inch and three-quarters of an inch thick provides a stronger weld that requires less filler material. Double-J butt welds have one piece that has a \"J\" shape from both directions and the other piece is square.\nU-joints.\nSingle-U butt welds are welds that have both edges of the weld surface shaped like a J, but once they come together, they form a U. Double-U joints have a U formation on both the top and bottom of the prepared joint. U-joints are the most expensive edge to prepare and weld. They are usually used on thick base metals where a V-groove would be at such an extreme angle that it would cost too much to fill.\nTee-Joints.\nThe Tee Weld Joint is formed when two bars or sheets are joined perpendicular to each other in the form of a \"T\" shape. This weld is made from the resistance butt welding process. It can also be performed by Extrusion Welding. Usually two flat pieces of poly are welded at 90 degrees to each other, and extrusion welded on both sides.\nOthers.\nThin sheet metals are often flanged to produce edge-flange or corner-flange welds. These welds are typically made without the addition of filler metal because the flange melts and provides all the filler needed. Pipes and tubing can be made from rolling and welding together strips, sheets, or plates of material.\nFlare-groove joints are used for welding metals that, because of their shape, form a convenient groove for welding, such as a pipe against a flat surface.\nSelection of the right weld joint depends on the thickness and process used. The square welds are the most economical for pieces thinner than 3/8”, because they don’t require the edge to be prepared. Double-groove welds are the most economical for thicker pieces because they require less weld material and time. The use of fusion welding is common for closed single-bevel, closed single J, open single J, and closed double J butt joints. The use of gas and arc welding is ideal for double-bevel, closed double-bevel, open double-bevel, single-bevel, and open single-bevel butt welds.\nBelow are listed ideal joint thicknesses for the various types of butt. When the thickness of a butt weld is defined it is measured at the thinner part and does not compensate for the weld reinforcement.\nCruciform.\nA \"\" is a specific joint in which four spaces are created by the welding of three plates of metal at right angles. Cruciform joints suffer fatigue when subjected to continuously varying loads.\nIn the American Bureau of Shipping Rules for Steel Vessels, cruciform joints may be considered a double barrier if the two substances requiring a double barrier are in opposite corners diagonally. Double barriers are often required to separate oil and seawater, chemicals and potable water, etc.\nPlate edge preparation.\nIn common welding practices, the welding surface must be prepared to ensure the strongest weld possible. Preparation is needed for all forms of welding and all types of joints. Generally, butt welds require very little preparation, but some is still needed for the best results. Plate edges can be prepared for butt joints in various ways, but the five most common techniques are oxyacetylene cutting (oxy-fuel welding and cutting), machining, chipping, grinding, and air carbon-arc cutting or gouging. Each technique has unique advantages to their use.\nFor steel materials, oxyacetylene cutting is the most common form of preparation. This technique is advantageous because of its speed, low cost, and adaptability. Machining is the most effective for reproducibility and mass production of parts. The preparation of J or U joints is commonly prepared by machining due to the need for high accuracy. The chipping method is used to prepare parts that were produced by casting. The use of grinding to prepare pieces is reserved for small sections that cannot be prepared by other methods. Air carbon arc cutting is common in industries that work with stainless steels, cast iron, or ordinary carbon steel.\nPrior to welding dissimilar materials, one or both faces of the groove can be buttered. The buttered layer can be the same alloy as the filler metal or a different filler metal that will act as a buffer between the two metals to be joined.", "Engineering,_Manufacturing": 1.0000063181, "qwen": "Yes"}
{"id": "23703319", "revid": "45343971", "url": "https://en.wikipedia.org/wiki?curid=23703319", "title": "Manufacturing readiness level", "text": "The manufacturing readiness level (MRL) is a measure to assess the maturity of manufacturing readiness, similar to how technology readiness levels (TRL) are used for technology readiness. They can be used in general industry assessments, or for more specific application in assessing capabilities of possible suppliers. \nThe Government Accountability Office (GAO) has described it as best practice for improving acquisition outcomes. It was developed by the United States Department of Defense (DOD), who adopted the usage of MRLs in 2005. However, GAO continued to note inconsistent application across DOD components. In 2011, consideration of manufacturing readiness and related processes of potential contractors and subcontractors was made mandatory as part of the source selection process in major acquisition programs.\nMRLs are quantitative measures used to assess the maturity of a given technology, component or system from a manufacturing perspective. They are used to provide decision makers at all levels with a common understanding of the relative maturity and attendant risks associated with manufacturing technologies, products, and processes being considered. Manufacturing risk identification and management must begin at the earliest stages of technology development, and continue vigorously throughout each stage of a program’s life-cycles. \nManufacturing readiness level definitions were developed by a joint DOD/industry working group under the sponsorship of the Joint Defense Manufacturing Technology Panel (JDMTP). The intent was to create a measurement scale that would serve the same purpose for manufacturing readiness as Technology Readiness Levels serve for technology readiness – to provide a common metric and vocabulary for assessing and discussing manufacturing maturity, risk and readiness. MRLs were designed with a numbering system to be roughly congruent with comparable levels of TRLs for synergy and ease of understanding and use.\nWhy manufacturing readiness?\nMRLs are assessed to:\nImmature manufacturing processes may lead to the following problems: \nAssessing technology readiness levels does leave some major transition questions unanswered: \nManufacturing readiness assessments (MRAs) address these unanswered questions in order to reduce manufacturing risk. However, it still does not address the question of whether the product is reliable or maintainable.\nDefinitions.\nThe following has been adopted by the DOD as appropriate in assessing manufacturing readiness levels:\nDimensions in Assessing Readiness.\nMRLs are assessed in multiple dimensions (referred to as \"threads\" within DOD):\nExamples.\nSeveral traditional non-proprietary non-confidential examples are described below illustrating the use of MRL methodology in joining manufacturing.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "23713348", "revid": "1113566054", "url": "https://en.wikipedia.org/wiki?curid=23713348", "title": "Standard Sanitary Manufacturing Company", "text": "The original Standard Sanitary was formed when James West Arrott of James West Arrott Insurance company in Pittsburgh, Pennsylvania took over a bankrupt hooper company that could not pay their insurance premiums. Along with Francis Torrance (they were related as they married the Waddell sisters) they learned about the enamelization of porcelain in Europe and brought that technique to America by first making bathtubs and then toilets and sinks. It was in the late 1890’s that Standard Sanitary was combined with other plumbing manufacturers to form the Standard Sanitary Manufacturing Company. \nThe Standard Sanitary Manufacturing Company was an American manufacturer of bathroom fixtures. It was formed in 1875 by the merger of the Ahrens and Ott Manufacturing Company, the Standard Manufacturing Company, the Dawes and Myler Manufacturing Company, and 6 other plants which were consolidated to form the Standard Manufacturing Company, headquartered in Pittsburgh, with Theodore Ahrens (Jr.) as its first president. He held this position, and others, until 1934.\nIn 1929, the company merged with the American Radiator Company to form the American Radiator and Standard Sanitary Corporation.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "46467403", "revid": "11521989", "url": "https://en.wikipedia.org/wiki?curid=46467403", "title": "CNC machine tool monitoring by AE sensors", "text": "A machine tool monitoring system is a flow of information and system processing in which the information selection, obtaining data, processing of information and decision making on the refined information are integrated. The aim of tool condition monitoring is to detect early the disturbances in the machining process and wear of machine tool components. \nThe condition of tool has been researched extensively in the past and have focused on detection of tool wear, tool breakage and the estimation of remaining tool life. It is very important for on-line identification of tool condition in machining process for enhanced productivity, better quality of parts and lower costs for unmanned, automated manufacturing systems.\nTechniques of machine tool monitoring.\nMachine tool monitoring can be done with or without additional sensors. Using additional sensors, monitoring can be done by measuring:\nSensor-less machine tool monitoring is done by measuring internal drive signals such as:\nCombined measuring of multiple quantities is also possible.\nAcoustic emission sensor.\nMachine tool monitoring is explained with Acoustic Emission (AE) sensors. An AE sensor is commonly defined as the sound emitted as an elastic wave by a solid when it is deformed or struck, caused by the rapid release of localized stress energy. Therefore, it is an occurrence phenomenon which releases elastic energy into the material, which then propagates as an elastic wave. The detection frequency range of acoustic emission is from 1 kHz to 1 MHz. \nRapid stress-releasing events generate a spectrum of stress waves starting at 0 Hz and typically falling off at several MHz. AE can be related to an irreversible release of energy. It can also be generated from sources not involving material failure including friction, cavitation and impact. The three major applications of AE sensors phenomena are: a) Source location - determine the locations of occurrence of an event b) Material mechanical performance - evaluate and characterize materials/structures; and c Health monitoring – monitors the safety operation.\nHow an AE sensor monitors machine tool.\nAn AE sensor works on the principle of measuring the high-frequency energy signals produced during cutting process. It also measures the AE energy resulting from the fracture when a tool breaks. It is best suited to applications where the level of background AE signal is low compared to the sound of tool breakage. This makes the AE sensor ideal for breakage detection of small drills and taps. It is easy to install on both new and existing machines. \nAn AE sensor detects force proportional monitoring signals even in machining operations, which generate very small cutting forces. In combination with true power, it increases the reliability of breakage monitoring. It is used especially with solid carbide tools, or very small tools on large machines and multi spindles. Most of the sensors have to be attached to the machine tool surface. However, there are alternative methods of AE wave transmitting. A rotating, wireless AE sensor consists of a rotating sensor and a fixed receiver. An AE sensor can also receive the acoustic waves via a jet of cooling lubricant, which can be connected directly to the tool or workpiece.\nThe machine tool monitoring systems commonly use sensors for measuring cutting force components or quantities related to cutting force (power, torque, distance/displacement and strain). AE sensors are relatively easy to install in existing or new machines, and do not influence machine integrity and stiffness. All systems suppliers also use acoustic emission sensors, especially for monitoring small tools and for grinding. \nAll sensors used in machine tool monitoring systems are well adjusted to harsh machine tool environments. The difficulties in designing reliable machine tool monitoring can be related to the complexity of the machining process itself, which may have one or more of the following characteristics, apart from the changes of the machine tool itself.", "Engineering,_Manufacturing": 1.0000082254, "qwen": "Yes"}
{"id": "1527151", "revid": "42677165", "url": "https://en.wikipedia.org/wiki?curid=1527151", "title": "Speeds and feeds", "text": "The phrase speeds and feeds or feeds and speeds refers to two separate velocities in machine tool practice, cutting speed and feed rate. They are often considered as a pair because of their combined effect on the cutting process. Each, however, can also be considered and analyzed in its own right.\n\"Cutting speed\" (also called \"surface speed\" or simply \"speed\") is the speed difference (relative velocity) between the cutting tool and the surface of the workpiece it is operating on. It is expressed in units of distance across the workpiece surface per unit of time, typically surface feet per minute (sfm) or meters per minute (m/min). \"Feed rate\" (also often styled as a solid compound, \"feedrate\", or called simply \"feed\") is the relative velocity at which the cutter is advanced along the workpiece; its vector is perpendicular to the vector of cutting speed. Feed rate units depend on the motion of the tool and workpiece; when the workpiece rotates (\"e.g.\", in turning and boring), the units are almost always distance per spindle revolution (inches per revolution [in/rev or ipr] or millimeters per revolution [mm/rev]). When the workpiece does not rotate (\"e.g.\", in milling), the units are typically distance per time (inches per minute [in/min or ipm] or millimeters per minute [mm/min]), although distance per revolution or per cutter tooth are also sometimes used.\nIf variables such as cutter geometry and the rigidity of the machine tool and its tooling setup could be ideally maximized (and reduced to negligible constants), then only a lack of power (that is, kilowatts or horsepower) available to the spindle would prevent the use of the maximum possible speeds and feeds for any given workpiece material and cutter material. Of course, in reality those other variables are dynamic and not negligible, but there is still a correlation between power available and feeds and speeds employed. In practice, lack of rigidity is usually the limiting constraint.\nThe phrases \"speeds and feeds\" or \"feeds and speeds\" have sometimes been used metaphorically to refer to the execution details of a plan, which only skilled technicians (as opposed to designers or managers) would know.\nCutting speed.\nCutting speed may be defined as the rate at the workpiece surface, irrespective of the machining operation used. A cutting speed for mild steel of 100 ft/min is the same whether it is the speed of the cutter passing over the workpiece, such as in a turning operation, or the speed of the cutter moving past a workpiece, such as in a milling operation. The cutting conditions will affect the value of this surface speed for mild steel.\nSchematically, speed at the workpiece surface can be thought of as the tangential speed at the tool-cutter interface, that is, how fast the material moves past the cutting edge of the tool, although \"which surface to focus on\" is a topic with several valid answers. In drilling and milling, the outside diameter of the tool is the widely agreed surface. In turning and boring, the surface can be defined on either side of the depth of cut, that is, either the starting surface or the ending surface, with neither definition being \"wrong\" as long as the people involved understand the difference. An experienced machinist summed this up succinctly as \"the diameter I am turning from\" versus \"the diameter I am turning to.\" He uses the \"from\", not the \"to\", and explains why, while acknowledging that some others do not. The logic of focusing on the largest diameter involved (OD of drill or end mill, starting diameter of turned workpiece) is that this is where the highest tangential speed is, with the most heat generation, which is the main driver of tool wear.\nThere will be an optimum cutting speed for each material and set of machining conditions, and the spindle speed (RPM) can be calculated from this speed. Factors affecting the calculation of cutting speed are:\nCutting speeds are calculated on the assumption that optimum cutting conditions exist. These include:\nThe cutting \"speed\" is given as a set of constants that are available from the material manufacturer or supplier. The most common materials are available in reference books or charts, but will always be subject to adjustment depending on the cutting conditions. The following table gives the cutting speeds for a selection of common materials under one set of conditions. The conditions are a tool life of 1 hour, dry cutting (no coolant), and at medium feeds, so they may appear to be incorrect depending on circumstances. These cutting speeds may change if, for instance, adequate coolant is available or an improved grade of HSS is used (such as one that includes [cobalt]).\nMachinability rating.\nThe machinability rating of a material attempts to quantify the machinability of various materials. It is expressed as a percentage or a normalized value. The American Iron and Steel Institute (AISI) determined machinability ratings for a wide variety of materials by running turning tests at 180 surface feet per minute (sfpm). It then arbitrarily assigned 160 Brinell B1112 steel a machinability rating of 100%. The machinability rating is determined by measuring the weighed averages of the normal cutting speed, surface finish, and tool life for each material. Note that a material with a machinability rating less than 100% would be more difficult to machine than B1112 and material and a value more than 100% would be easier.\nMachinability ratings can be used in conjunction with the Taylor tool life equation, in order to determine cutting speeds or tool life. It is known that B1112 has a tool life of 60 minutes at a cutting speed of 100 sfpm. If a material has a machinability rating of 70%, it can be determined, with the above knowns, that in order to maintain the same tool life (60 minutes), the cutting speed must be 70 sfpm (assuming the same tooling is used).\nWhen calculating for copper alloys, the machine rating is arrived at by assuming the 100 rating of 600 SFM. For example, phosphorus bronze (grades A–D) has a machinability rating of 20. This means that phosphor bronze runs at 20% the speed of 600 SFM or 120 SFM. However, 165 SFM is generally accepted as the basic 100% rating for \"grading steels\".\nFormula\nCutting Speed (V)= [πDN]/1000 m/min\nWhere \nD=Diameter of Workpiece in meter or millimeter\nN=Spindle Speed in rpm\nSpindle speed.\nThe spindle speed is the rotational frequency of the spindle of the machine, measured in revolutions per minute (RPM). The preferred speed is determined by working backward from the desired surface speed (sfm or m/min) and incorporating the diameter (of workpiece or cutter).\nThe spindle may hold the:\nExcessive spindle speed will cause premature tool wear, breakages, and can cause tool chatter, all of which can lead to potentially dangerous conditions. Using the correct spindle speed for the material and tools will greatly enhance tool life and the quality of the surface finish.\nFor a given machining operation, the cutting speed will remain constant for most situations; therefore the spindle speed will also remain constant. However, facing, forming, parting off, and recess operations on a lathe or screw machine involve the machining of a constantly changing diameter. Ideally, this means changing the spindle speed as the cut advances across the face of the workpiece, producing constant surface speed (CSS). Mechanical arrangements to effect CSS have existed for centuries, but they were never applied commonly to machine tool control. In the pre-CNC era, the ideal of CSS was ignored for most work. For unusual work that demanded it, special pains were taken to achieve it. The introduction of CNC-controlled lathes has provided a practical, everyday solution via automated CSS Machining Process Monitoring and Control. By means of the machine's software and variable speed electric motors, the lathe can increase the RPM of the spindle as the cutter gets closer to the center of the part.\nGrinding wheels are designed to be run at a maximum safe speed, the spindle speed of the grinding machine may be variable but this should only be changed with due attention to the safe working speed of the wheel. As a wheel wears it will decrease in diameter, and its effective cutting speed will be reduced. Some grinders have the provision to increase the spindle speed, which corrects for this loss of cutting ability; however, increasing the speed beyond the wheels rating will destroy the wheel and create a serious hazard to life and limb.\nGenerally speaking, spindle speeds and feed rates are less critical in woodworking than metalworking. Most woodworking machines including power saws such as circular saws and band saws, jointers, Thickness planers rotate at a fixed RPM. In those machines, cutting speed is regulated through the feed rate. The required feed rate can be extremely variable depending on the power of the motor, the hardness of the wood or other material being machined, and the sharpness of the cutting tool.\nIn woodworking, the ideal feed rate is one that is slow enough not to bog down the motor, yet fast enough to avoid burning the material. Certain woods, such as black cherry and maple are more prone to burning than others. The right feed rate is usually obtained by \"feel\" if the material is hand fed, or by trial and error if a power feeder is used. In thicknessers (planers), the wood is usually fed automatically through rubber or corrugated steel rollers. Some of these machines allow varying the feed rate, usually by changing pulleys. A slower feed rate usually results in a finer surface as more cuts are made for any length of wood.\nSpindle speed becomes important in the operation of routers, spindle moulders or shapers, and drills. Older and smaller routers often rotate at a fixed spindle speed, usually between 20,000 and 25,000 rpm. While these speeds are fine for small router bits, using larger bits, say more than or 25 millimeters in diameter, can be dangerous and can lead to chatter. Larger routers now have variable speeds and larger bits require slower speed. Drilling wood generally uses higher spindle speeds than metal, and the speed is not as critical. However, larger diameter drill bits do require slower speeds to avoid burning.\nCutting feeds and speeds, and the spindle speeds that are derived from them, are the \"ideal\" cutting conditions for a tool. If the conditions are less than ideal then adjustments are made to the spindle's speed, this adjustment is usually a reduction in RPM to the closest available speed, or one that is deemed (through knowledge and experience) to be correct.\nSome materials, such as machinable wax, can be cut at a wide variety of spindle speeds, while others, such as stainless steel require much more careful control as the cutting speed is critical, to avoid overheating both the cutter and workpiece. Stainless steel is one material that hardens very easily under cold working, therefore insufficient feed rate or incorrect spindle speed can lead to less than ideal cutting conditions as the work piece will quickly harden and resist the tool's cutting action. The liberal application of cutting fluid can improve these cutting conditions; however, the correct selection of speeds is the critical factor.\nSpindle speed calculations.\nMost metalworking books have nomograms or tables of spindle speeds and feed rates for different cutters and workpiece materials; similar tables are also likely available from the manufacturer of the cutter used.\nThe spindle speeds may be calculated for all machining operations once the SFM or MPM is known. In most cases, we are dealing with a cylindrical object such as a milling cutter or a workpiece turning in a lathe so we need to determine the speed at the periphery of this round object. This speed at the periphery (of a point on the circumference, moving past a stationary point) will depend on the rotational speed (RPM) and diameter of the object.\nOne analogy would be a skateboard rider and a bicycle rider travelling side by side along the road. For a given surface speed (the speed of this pair along the road) the rotational speed (RPM) of their wheels (large for the skater and small for the bicycle rider) will be different. This rotational speed (RPM) is what we are calculating, given a fixed surface speed (speed along the road) and known values for their wheel sizes (cutter or workpiece).\nThe following formulae may be used to estimate this value.\nApproximation.\nThe exact RPM is not always needed, a close approximation will work (using 3 for the value of formula_1).\ne.g. for a cutting speed of 100 ft/min (a plain HSS steel cutter on mild steel) and diameter of 10 inches (the cutter or the work piece)\nand, for an example using metric values, where the cutting speed is 30 m/min and a diameter of 10 mm (0.01 m),\nAccuracy.\nHowever, for more accurate calculations, and at the expense of simplicity, this formula can be used:\nand using the same example\nand using the same example as above\nwhere:\nFeed rate.\nFeed rate is the velocity at which the cutter is fed, that is, advanced against the workpiece. It is expressed in units of distance per revolution for turning and boring (typically \"inches per revolution\" [\"ipr\"] or \"millimeters per revolution\"). It can be expressed thus for milling also, but it is often expressed in units of distance per time for milling (typically \"inches per minute\" [\"ipm\"] or \"millimeters per minute\"), with considerations of how many teeth (or flutes) the cutter has then determined what that means for each tooth.\nFeed rate is dependent on the:\nWhen deciding what feed rate to use for a certain cutting operation, the calculation is fairly straightforward for single-point cutting tools, because all of the cutting work is done at one point (done by \"one tooth\", as it were). With a milling machine or jointer, where multi-tipped/multi-fluted cutting tools are involved, then the desired feed rate becomes dependent on the number of teeth on the cutter, as well as the desired amount of material per tooth to cut (expressed as chip load). The greater the number of cutting edges, the higher the feed rate permissible: for a cutting edge to work efficiently it must remove sufficient material to cut rather than rub; it also must do its fair share of work.\nThe ratio of the spindle speed and the feed rate controls how aggressive the cut is, and the nature of the swarf formed.\nFormula to determine feed rate.\nThis formula can be used to figure out the feed rate that the cutter travels into or around the work. This would apply to cutters on a milling machine, drill press and a number of other machine tools. This is not to be used on the lathe for turning operations, as the feed rate on a lathe is given as \"feed per revolution.\"\nformula_8\nWhere:\nDepth of cut.\nCutting speed and feed rate come together with \"depth of cut\" to determine the \"material removal rate\", which is the volume of workpiece material (metal, wood, plastic, etc.) that can be removed per time unit.\nInterrelationship of theory and practice.\nSpeed-and-feed selection is analogous to other examples of applied science, such as meteorology or pharmacology, in that the theoretical modeling is necessary and useful but can never fully predict the reality of specific cases because of the massively multivariate environment. Just as weather forecasts or drug dosages can be modeled with fair accuracy, but never with complete certainty, machinists can predict with charts and formulas the approximate speed and feed values that will work best on a particular job, but cannot know the exact optimal values until running the job. In CNC machining, usually the programmer programs speeds and feedrates that are as maximally tuned as calculations and general guidelines can supply. The operator then fine-tunes the values while running the machine, based on sights, sounds, smells, temperatures, tolerance holding, and tool tip lifespan. Under proper management, the revised values are captured for future use, so that when a program is run again later, this work need not be duplicated.\nAs with meteorology and pharmacology, however, the interrelationship of theory and practice has been developing over decades as the theory part of the balance becomes more advanced thanks to information technology. For example, an effort called the Machine Tool Genome Project is working toward providing the computer modeling (simulation) needed to predict optimal speed-and-feed combinations for particular setups in any internet-connected shop with less local experimentation and testing. Instead of the only option being the measuring and testing of the behavior of its own equipment, it will benefit from others' experience and simulation; in a sense, rather than 'reinventing a wheel', it will be able to 'make better use of existing wheels already developed by others in remote locations'.\nAcademic research examples.\nSpeeds and feeds have been studied scientifically since at least the 1890s. The work is typically done in engineering laboratories, with the funding coming from three basic roots: corporations, governments (including their militaries), and universities. All three types of institution have invested large amounts of money in the cause, often in collaborative partnerships. Examples of such work are highlighted below.\nIn the 1890s through 1910s, Frederick Winslow Taylor performed turning experiments that became famous (and seminal). He developed Taylor's Equation for Tool Life Expectancy.\nScientific study by Holz and De Leeuw of the Cincinnati Milling Machine Company did for milling cutters what F. W. Taylor had done for single-point cutters.\n\"Following World War II, many new alloys were developed. New standards were needed to increase [U.S.] American productivity. Metcut Research Associates, with technical support from the Air Force Materials Laboratory and the Army Science and Technology Laboratory, published the first Machining Data Handbook in 1966. The recommended speeds and feeds provided in this book were the result of extensive testing to determine optimum tool life under controlled conditions for every material of the day, operation and hardness.\"\nA study on the effect of the variation of cutting parameters in the surface integrity in turning of an AISI 304 stainless steel revealed that the feed rate has the greatest impairing effect on the quality of the surface, and that besides the achievement of the desired roughness profile, it is necessary to analyze the effect of speed and feed on the creation of micropits and microdefects on the machined surface. Moreover, they found that the conventional empirical relation that relates feed rate to roughness value does not fit adequately for low cutting speeds.", "Engineering,_Manufacturing": 0.9999914169, "qwen": "Yes"}
{"id": "1528221", "revid": "44120587", "url": "https://en.wikipedia.org/wiki?curid=1528221", "title": "Sheet metal", "text": "Sheet metal is metal formed into thin, flat pieces, usually by an industrial process. Sheet metal is one of the fundamental forms used in metalworking, and it can be cut and bent into a variety of shapes. \nThicknesses can vary significantly; extremely thin sheets are considered foil or leaf, and pieces thicker than 6 mm (0.25 in) are considered plate, such as plate steel, a class of structural steel.\nSheet metal is available in flat pieces or coiled strips. The coils are formed by running a continuous sheet of metal through a roll slitter.\nIn most of the world, sheet metal thickness is consistently specified in millimeters. In the U.S., the thickness of sheet metal is commonly specified by a traditional, non-linear measure known as its gauge. The larger the gauge number, the thinner the metal. Commonly used steel sheet metal ranges from 30 gauge to about 7 gauge. Gauge differs between ferrous (iron-based) metals and nonferrous metals such as aluminum or copper. Copper thickness, for example, is measured in ounces, representing the weight of copper contained in an area of one square foot. Parts manufactured from sheet metal must maintain a uniform thickness for ideal results.\nThere are many different metals that can be made into sheet metal, such as aluminium, brass, copper, steel, tin, nickel and titanium. For decorative uses, some important sheet metals include silver, gold, and platinum (platinum sheet metal is also utilized as a catalyst).\nSheet metal is used in automobile and truck (lorry) bodies, major appliances, airplane fuselages and wings, tinplate for tin cans, roofing for buildings (architecture), and many other applications. Sheet metal of iron and other materials with high magnetic permeability, also known as laminated steel cores, has applications in transformers and electric machines. Historically, an important use of sheet metal was in plate armor worn by cavalry, and sheet metal continues to have many decorative uses, including in horse tack. Sheet metal workers are also known as \"tin bashers\" (or \"tin knockers\"), a name derived from the hammering of panel seams when installing tin roofs.\nHistory.\nHand-hammered metal sheets have been used since ancient times for architectural purposes. Water-powered rolling mills replaced the manual process in the late 17th century. The process of flattening metal sheets required large rotating iron cylinders which pressed metal pieces into sheets. The metals suited for this were lead, copper, zinc, iron and later steel. Tin was often used to coat iron and steel sheets to prevent it from rusting. This tin-coated sheet metal was called \"tinplate.\" Sheet metals appeared in the United States in the 1870s, being used for shingle roofing, stamped ornamental ceilings, and exterior façades. Sheet metal ceilings were only popularly known as \"tin ceilings\" later as manufacturers of the period did not use the term. The popularity of both shingles and ceilings encouraged widespread production. With further advances of steel sheet metal production in the 1890s, the promise of being cheap, durable, easy to install, lightweight and fireproof gave the middle-class a significant appetite for sheet metal products. It was not until the 1930s and WWII that metals became scarce and the sheet metal industry began to collapse. However, some American companies, such as the W.F. Norman Corporation, were able to stay in business by making other products until Historic preservation projects aided the revival of ornamental sheet metal.\nMaterials.\nStainless steel.\nGrade 304 is the most common of the three grades. It offers good corrosion resistance while maintaining formability and weldability. Available finishes are #2B, #3, and #4. Grade 303 is not available in sheet form.\nGrade 316 possesses more corrosion resistance and strength at elevated temperatures than 304. It is commonly used for pumps, valves, chemical equipment, and marine applications. Available finishes are #2B, #3, and #4.\nGrade 410 is a heat treatable stainless steel, but it has a lower corrosion resistance than the other grades. It is commonly used in cutlery. The only available finish is dull.\nGrade 430 is a popular grade, low-cost alternative to series 300's grades. This is used when high corrosion resistance is not a primary criterion. Common grade for appliance products, often with a brushed finish.\nAluminum.\nAluminum, or aluminium in British English, is also a popular metal used in sheet metal due to its flexibility, wide range of options, cost effectiveness, and other properties. The four most common aluminium grades available as sheet metal are 1100-H14, 3003-H14, 5052-H32, and 6061-T6.\nGrade 1100-H14 is commercially pure aluminium, highly chemical and weather resistant. It is ductile enough for deep drawing and weldable, but has low strength. It is commonly used in chemical processing equipment, light reflectors, and jewelry.\nGrade 3003-H14 is stronger than 1100, while maintaining the same formability and low cost. It is corrosion resistant and weldable. It is often used in stampings, spun and drawn parts, mail boxes, cabinets, tanks, and fan blades.\nGrade 5052-H32 is much stronger than 3003 while still maintaining good formability. It maintains high corrosion resistance and weldability. Common applications include electronic chassis, tanks, and pressure vessels.\nGrade 6061-T6 is a common heat-treated structural aluminium alloy. It is weldable, corrosion resistant, and stronger than 5052, but not as formable. It loses some of its strength when welded. It is used in modern aircraft structures.\nBrass.\nBrass is an alloy of copper, which is widely used as a sheet metal. It has more strength, corrosion resistance and formability when compared to copper while retaining its conductivity.\nIn sheet hydroforming, variation in incoming sheet coil properties is a common problem for forming process, especially with materials for automotive applications. Even though incoming sheet coil may meet tensile test specifications, high rejection rate is often observed in production due to inconsistent material behavior. Thus there is a strong need for a discriminating method for testing incoming sheet material formability. The hydraulic sheet bulge test emulates biaxial deformation conditions commonly seen in production operations.\nFor forming limit curves of materials aluminium, mild steel and brass. Theoretical analysis is carried out by deriving governing equations for determining of equivalent stress and equivalent strain based on the bulging to be spherical and Tresca's yield criterion with the associated flow rule. For experimentation circular grid analysis is one of the most effective methods.\nGauge.\nUse of gauge numbers to designate sheet metal thickness is discouraged by numerous international standards organizations. For example, ASTM states in specification ASTM A480-10a: \"The use of gauge number is discouraged as being an archaic term of limited usefulness not having general agreement on meaning.\"\nManufacturers' Standard Gauge for Sheet Steel is based on an average density of 41.82 lb per square foot per inch thick, equivalent to . Gauge is defined differently for ferrous (iron-based) and non-ferrous metals (e.g. aluminium and brass).\nThe gauge thicknesses shown in column 2 (U.S. standard sheet and plate iron and steel decimal inch (mm)) seem somewhat arbitrary. The progression of thicknesses is clear in column 3 (U.S. standard for sheet and plate iron and steel 64ths inch (delta)). The thicknesses vary first by inch in higher thicknesses and then step down to increments of inch, then inch, with the final increments at decimal fractions of inch. \nSome steel tubes are manufactured by folding a single steel sheet into a square/circle and welding the seam together. Their wall thickness has a similar (but distinct) gauge to the thickness of steel sheets. \nTolerances.\nDuring the rolling process the rollers bow slightly, which results in the sheets being thinner on the edges. The tolerances in the table and attachments reflect current manufacturing practices and commercial standards and are not representative of the Manufacturer's Standard Gauge, which has no inherent tolerances.\nForming processes.\nBending.\nThe equation for estimating the maximum bending force is,\nformula_1,\nwhere \"k\" is a factor taking into account several parameters including friction. \"T\" is the ultimate tensile strength of the metal. \"L\" and \"t\" are the length and thickness of the sheet metal, respectively. The variable \"W\" is the open width of a V-die or wiping die.\nCurling.\nThe curling process is used to form an edge on a ring. This process is used to remove sharp edges. It also increases the moment of inertia near the curled end.\nThe flare/burr should be turned away from the die. It is used to curl a material of specific thickness. Tool steel is generally used due to the amount of wear done by operation.\nDecambering.\nIt is a metal working process of removing camber, the horizontal bend, from a strip shaped material. It may be done to a finite length section or coils. It resembles flattening of leveling process, but on a deformed edge.\nDeep drawing.\nDrawing is a forming process in which the metal is stretched over a form or die. In deep drawing the depth of the part being made is more than half its diameter. Deep drawing is used for making automotive fuel tanks, kitchen sinks, two-piece aluminum cans, etc. Deep drawing is generally done in multiple steps called draw reductions. The greater the depth, the more reductions are required. Deep drawing may also be accomplished with fewer reductions by heating the workpiece, for example in sink manufacture.\nIn many cases, material is rolled at the mill in both directions to aid in deep drawing. This leads to a more uniform grain structure which limits tearing and is referred to as \"draw quality\" material.\nExpanding.\nExpanding is a process of cutting or stamping slits in alternating pattern much like the stretcher bond in brickwork and then stretching the sheet open in accordion-like fashion. It is used in applications where air and water flow are desired as well as when light weight is desired at cost of a solid flat surface. A similar process is used in other materials such as paper to create a low cost packing paper with better supportive properties than flat paper alone.\nHemming and seaming.\nHemming is a process of folding the edge of sheet metal onto itself to reinforce that edge. Seaming is a process of folding two sheets of metal together to form a joint.\nHydroforming.\nHydroforming is a process that is analogous to deep drawing, in that the part is formed by stretching the blank over a stationary die. The force required is generated by the direct application of extremely high hydrostatic pressure to the workpiece or to a bladder that is in contact with the workpiece, rather than by the movable part of a die in a mechanical or hydraulic press. Unlike deep drawing, hydroforming usually does not involve draw reductions—the piece is formed in a single step.\nIncremental sheet forming.\nIncremental sheet forming or ISF forming process is basically sheet metal working or sheet metal forming process. In this case, sheet is formed into final shape by a series of processes in which small incremental deformation can be done in each series.\nIroning.\nIroning is a sheet metal working or sheet metal forming process. It uniformly thins the workpiece in a specific area. This is a very useful process. It is used to produce a uniform wall thickness part with a high height-to-diameter ratio.\nIt is used in making aluminium beverage cans.\nLaser cutting.\nSheet metal can be cut in various ways, from hand tools called tin snips up to very large powered shears. With the advances in technology, sheet metal cutting has turned to computers for precise cutting. Many sheet metal cutting operations are based on computer numerically controlled (CNC) laser cutting or multi-tool CNC punch press.\nCNC laser involves moving a lens assembly carrying a beam of laser light over the surface of the metal. Oxygen, nitrogen or air is fed through the same nozzle from which the laser beam exits. The metal is heated and burnt by the laser beam, cutting the metal sheet. The quality of the edge can be mirror smooth and a precision of around can be obtained. Cutting speeds on thin sheet can be as high as per minute. Most laser cutting systems use a based laser source with a wavelength of around 10 µm; some more recent systems use a YAG based laser with a wavelength of around 1 µm.\nPhotochemical machining.\nPhotochemical machining, also known as photo etching, is a tightly controlled corrosion process which is used to produce complex metal parts from sheet metal with very fine detail. The photo etching process involves photo sensitive polymer being applied to a raw metal sheet. Using CAD designed photo-tools as stencils, the metal is exposed to UV light to leave a design pattern, which is developed and etched from the metal sheet.\nPerforating.\nPerforating is a cutting process that punches multiple small holes close together in a flat workpiece. Perforated sheet metal is used to make a wide variety of surface cutting tools, such as the surform.\nPress brake forming.\nThis is a form of bending used to produce long, thin sheet metal parts. The machine that bends the metal is called a press brake. The lower part of the press contains a V-shaped groove called the die. The upper part of the press contains a punch that presses the sheet metal down into the v-shaped die, causing it to bend. There are several techniques used, but the most common modern method is \"air bending\". Here, the die has a sharper angle than the required bend (typically 85 degrees for a 90 degree bend) and the upper tool is precisely controlled in its stroke to push the metal down the required amount to bend it through 90 degrees. Typically, a general purpose machine has an available bending force of around 25 tons per meter of length. The opening width of the lower die is typically 8 to 10 times the thickness of the metal to be bent (for example, 5 mm material could be bent in a 40 mm die). The inner radius of the bend formed in the metal is determined not by the radius of the upper tool, but by the lower die width. Typically, the inner radius is equal to 1/6 of the V-width used in the forming process.\nThe press usually has some sort of back gauge to position depth of the bend along the workpiece. The backgauge can be computer controlled to allow the operator to make a series of bends in a component to a high degree of accuracy. Simple machines control only the backstop, more advanced machines control the position and angle of the stop, its height and the position of the two reference pegs used to locate the material. The machine can also record the exact position and pressure required for each bending operation to allow the operator to achieve a perfect 90 degree bend across a variety of operations on the part.\nPunching.\nPunching is performed by placing the sheet of metal stock between a punch and a die mounted in a press. The punch and die are made of hardened steel and are the same shape. The punch is sized to be a very close fit in the die. The press pushes the punch against and into the die with enough force to cut a hole in the stock. In some cases the punch and die \"nest\" together to create a depression in the stock. In progressive stamping, a coil of stock is fed into a long die/punch set with many stages. Multiple simple shaped holes may be produced in one stage, but complex holes are created in multiple stages. In the final stage, the part is punched free from the \"web\".\nA typical CNC turret punch has a choice of up to 60 tools in a \"turret\" that can be rotated to bring any tool to the punching position. A simple shape (e.g. a square, circle, or hexagon) is cut directly from the sheet. A complex shape can be cut out by making many square or rounded cuts around the perimeter. A punch is less flexible than a laser for cutting compound shapes, but faster for repetitive shapes (for example, the grille of an air-conditioning unit). A CNC punch can achieve 600 strokes per minute.\nA typical component (such as the side of a computer case) can be cut to high precision from a blank sheet in under 15 seconds by either a press or a laser CNC machine.\nRoll forming.\nA continuous bending operation for producing open profiles or welded tubes with long lengths or in large quantities.\nRolling.\nRolling is metal working or metal forming process. In this method, stock passes through one or more pair of rolls to reduce thickness. It is used to make thickness uniform. It is classified according to its temperature of rolling:\nSpinning.\nSpinning is used to make tubular (axis-symmetric) parts by fixing a piece of sheet stock to a rotating form (mandrel). Rollers or rigid tools press the stock against the form, stretching it until the stock takes the shape of the form. Spinning is used to make rocket motor casings, missile nose cones, satellite dishes and metal kitchen funnels.\nStamping.\nStamping includes a variety of operations such as punching, blanking, embossing, bending, flanging, and coining; simple or complex shapes can be formed at high production rates; tooling and equipment costs can be high, but labor costs are low.\nAlternatively, the related techniques repoussé and chasing have low tooling and equipment costs, but high labor costs.\nWater jet cutting.\nA water jet cutter, also known as a waterjet, is a tool capable of a controlled erosion into metal or other materials using a jet of water at high velocity and pressure, or a mixture of water and an abrasive substance.\nWheeling.\nThe process of using an English wheel is called wheeling. It is basically a metal working or metal forming process. An English wheel is used by a craftsperson to form compound curves from a flat sheet of metal of aluminium or steel. It is costly, as highly skilled labour is required. It can produce different panels by the same method. A stamping press is used for high numbers in production.\nFasteners.\nFasteners that are commonly used on sheet metal include: clecos, rivets, and sheet metal screws.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "1528972", "revid": "139104", "url": "https://en.wikipedia.org/wiki?curid=1528972", "title": "Through-hole technology", "text": "In electronics, through-hole technology (also spelled \"thru-hole\") is a manufacturing scheme in which leads on the components are inserted through holes drilled in printed circuit boards (PCB) and soldered to pads on the opposite side, either by manual assembly (hand placement) or by the use of automated insertion mount machines.\nHistory.\nThrough-hole technology almost completely replaced earlier electronics assembly techniques such as point-to-point construction. From the second generation of computers in the 1950s until surface-mount technology (SMT) became popular in the mid 1980s, every component on a typical PCB was a through-hole component. PCBs initially had tracks printed on one side only, later both sides, then multi-layer boards were in use. Through holes became plated-through holes (PTH) in order for the components to make contact with the required conductive layers. Plated-through holes are no longer required with SMT boards for making the component connections, but are still used for making interconnections between the layers and in this role are more usually called vias.\nLeads.\nAxial and radial leads.\nComponents with wire leads are generally used on through-hole boards. Axial leads protrude from each end of a typically cylindrical or elongated box-shaped component, on the geometrical axis of symmetry. Axial-leaded components resemble wire jumpers in shape, and can be used to span short distances on a board, or even otherwise unsupported through an open space in point-to-point wiring. Axial components do not protrude much above the surface of a board, producing a low-profile or flat configuration when placed \"lying down\" or parallel to the board.\nRadial leads project more or less in parallel from the same surface or aspect of a component package, rather than from opposite ends of the package. Originally, radial leads were defined as more-or-less following a radius of a cylindrical component (such as a ceramic disk capacitor). Over time, this definition was generalized in contrast to axial leads, and took on its current form. When placed on a board, radial components \"stand up\" perpendicular, occupying a smaller footprint on sometimes-scarce \"board real estate\", making them useful in many high-density designs. The parallel leads projecting from a single mounting surface gives radial components an overall \"plugin nature\", facilitating their use in high-speed automated component insertion (\"board-stuffing\") machines.\nWhen needed, an axial component can be effectively converted into a radial component, by bending one of its leads into a \"U\" shape so that it ends up close to and parallel with the other lead. Extra insulation with heat-shrink tubing may be used to prevent shorting out on nearby components. Conversely, a radial component can be pressed into service as an axial component by separating its leads as far as possible, and extending them into an overall length-spanning shape. These improvisations are often seen in breadboard or prototype construction, but are deprecated for mass production designs. This is because of difficulties in use with automated component placement machinery, and poorer reliability because of reduced vibration and mechanical shock resistance in the completed assembly.\nMultiple lead devices.\nFor electronic components with two or more leads, for example, diodes, transistors, ICs, or resistor packs, a range of standard-sized semiconductor packages are used, either directly onto the PCB or via a socket.\nCharacteristics.\nWhile through-hole mounting provides strong mechanical bonds when compared to SMT techniques, the additional drilling required makes the boards more expensive to produce. They also limit the available routing area for signal traces on layers immediately below the top layer on multilayer boards since the holes must pass through all layers to the opposite side. To that end, through-hole mounting techniques are now usually reserved for bulkier or heavier components such as electrolytic capacitors or semiconductors in larger packages such as the TO-220 that require the additional mounting strength, or for components such as plug connectors or electromechanical relays that require great strength in support.\nDesign engineers often prefer the larger through-hole rather than surface mount parts when prototyping, because they can be easily used with breadboard sockets. However, high-speed or high-frequency designs may require SMT technology to minimize stray inductance and capacitance in wire leads, which would impair circuit function. Ultra-compact designs may also dictate SMT construction, even in the prototype phase of design.\nThrough-hole components are ideal for prototyping circuits with breadboards using microprocessors such as Arduino or PICAXE. These components are large enough to be easy to use and solder by hand.", "Engineering,_Manufacturing": 0.9996826649, "qwen": "Yes"}
{"id": "7063356", "revid": "44920675", "url": "https://en.wikipedia.org/wiki?curid=7063356", "title": "Rautaruukki", "text": "Rautaruukki Oyj, using the marketing name Ruukki, is a Finnish company, headquartered in Helsinki, which manufactures and supplies metal-based components and systems to the construction and engineering industries. In 2014 Swedish SSAB bought Ruukki.\nThe company was founded in 1960 by the Finnish Government to provide the steel supply needed by the nation's heavy industries. Since part-privatization in 1994, the state has gradually decreased its holding in Rautaruukki.The firm consists of three business areas: construction, engineering and metals. Rautaruukki produces a range of products for clients in various industries, including cabins and chassis for heavy vehicles, hot rolled steel plates and coils, roofing sheets and building and bridge structures.\nOwnership.\nOn 31 December 2011the principal shareholders were:", "Engineering,_Manufacturing": 1.0000056028, "qwen": "Yes"}
{"id": "7071096", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=7071096", "title": "Engineering design process", "text": "The engineering design process, also known as the engineering method, is a common series of steps that engineers use in creating functional products and processes. The process is highly iterative - parts of the process often need to be repeated many times before another can be entered - though the part(s) that get iterated and the number of such cycles in any given project may vary.\nIt is a decision making process (often iterative) in which the basic sciences, mathematics, and engineering sciences are applied to convert resources optimally to meet a stated objective. Among the fundamental elements of the design process are the establishment of objectives and criteria, synthesis, analysis, construction, testing and evaluation. \nCommon stages of the engineering design process.\nIt's important to understand that there are various framings/articulations of the engineering design process. Different terminology employed may have varying degrees of overlap, which affects what steps get stated explicitly or deemed \"high level\" versus subordinate in any given model. This, of course, applies as much to any particular example steps/sequences given here.\nOne example framing of the engineering design process delineates the following stages: \"research, conceptualization, feasibility assessment, establishing design requirements, preliminary design, detailed design, production planning and tool design, and production\". Others, noting that \"different authors (in both research literature and in textbooks) define different phases of the design process with varying activities occurring within them,\" have suggested more simplified/generalized models - such as \"problem definition, conceptual design, preliminary design, detailed design, and design communication\". Another summary of the process, from European engineering design literature, includes \"clarification of the task, conceptual design, embodiment design, detail design\". (NOTE: In these examples, other key aspects - such as concept evaluation and prototyping - are subsets and/or extensions of one or more of the listed steps.)\nResearch.\nVarious stages of the design process (and even earlier) can involve a significant amount of time spent on locating information and research. Consideration should be given to the existing applicable literature, problems and successes associated with existing solutions, costs, and marketplace needs.\nThe source of information should be relevant. Reverse engineering can be an effective technique if other solutions are available on the market. Other sources of information include the Internet, local libraries, available government documents, personal organizations, trade journals, vendor catalogs and individual experts available.\nDesign requirements.\nEstablishing design requirements and conducting requirement analysis, sometimes termed problem definition (or deemed a related activity), is one of the most important elements in the design process, and this task is often performed at the same time as a feasibility analysis. The design requirements control the design of the product or process being developed, throughout the engineering design process. These include basic things like the functions, attributes, and specifications - determined after assessing user needs. Some design requirements include hardware and software parameters, maintainability, availability, and testability.\nFeasibility.\nIn some cases, a feasibility study is carried out after which schedules, resource plans and estimates for the next phase are developed. The feasibility study is an evaluation and analysis of the potential of a proposed project to support the process of decision making. It outlines and analyses alternatives or methods of achieving the desired outcome. The feasibility study helps to narrow the scope of the project to identify the best scenario.\nA feasibility report is generated following which Post Feasibility Review is performed.\nThe purpose of a feasibility assessment is to determine whether the engineer's project can proceed into the design phase. This is based on two criteria: the project needs to be based on an achievable idea, and it needs to be within cost constraints. It is important to have engineers with experience and good judgment to be involved in this portion of the feasibility study.\nConcept Generation.\nA concept study (conceptualization, conceptual design) is often a phase of project planning that includes producing ideas and taking into account the pros and cons of implementing those ideas. This stage of a project is done to minimize the likelihood of error, manage costs, assess risks, and evaluate the potential success of the intended project. In any event, once an engineering issue or problem is defined, potential solutions must be identified. These solutions can be found by using ideation, the mental process by which ideas are generated. In fact, this step is often termed Ideation or \"Concept Generation.\" The following are widely used techniques:\nVarious generated ideas must then undergo a concept evaluation step, which utilizes various tools to compare and contrast the relative strengths and weakness of possible alternatives.\nPreliminary design.\nThe preliminary design, or high-level design includes (also called FEED or Basic design), often bridges a gap between design conception and detailed design, particularly in cases where the level of conceptualization achieved during ideation is not sufficient for full evaluation. So in this task, the overall system configuration is defined, and schematics, diagrams, and layouts of the project may provide early project configuration. (This notably varies a lot by field, industry, and product.) During detailed design and optimization, the parameters of the part being created will change, but the preliminary design focuses on creating the general framework to build the project on.\nS. Blanchard and J. Fabrycky describe it as:\n“The ‘whats’ initiating conceptual design produce ‘hows’ from the conceptual design evaluation effort applied to feasible conceptual design concepts. Next, the ‘hows’ are taken into preliminary design through the means of allocated requirements. There they become ‘whats’ and drive preliminary design to address ‘hows’ at this lower level.”\nDetailed design.\nFollowing FEED is the Detailed Design (Detailed Engineering) phase, which may consist of procurement of materials as well.\nThis phase further elaborates each aspect of the project/product by complete description through solid modeling, drawings as well as specifications.\nComputer-aided design (CAD) programs have made the detailed design phase more efficient. For example, a CAD program can provide optimization to reduce volume without hindering a part's quality. It can also calculate stress and displacement using the finite element method to determine stresses throughout the part.\nProduction planning.\nThe production planning and tool design consists of planning how to mass-produce the product and which tools should be used in the manufacturing process. Tasks to complete in this step include selecting materials, selection of the production processes, determination of the sequence of operations, and selection of tools such as jigs, fixtures, metal cutting and metal or plastics forming tools. This task also involves additional prototype testing iterations to ensure the mass-produced version meets qualification testing standards.\nComparison with the scientific method.\nEngineering is formulating a problem that can be solved through design. Science is formulating a question that can be solved through investigation. \nThe engineering design process bears some similarity to the scientific method. Both processes begin with existing knowledge, and gradually become more specific in the search for \"knowledge\" (in the case of \"pure\" or basic science) or a \"solution\" (in the case of \"applied\" science, such as engineering). The key difference between the engineering process and the scientific process is that the engineering process focuses on design, creativity and innovation while the scientific process emphasizes Discovery (observation).\nDegree Programs.\nMethods are being taught and developed in Universities including:", "Engineering,_Manufacturing": 0.9999277592, "qwen": "Yes"}
{"id": "7080334", "revid": "31363479", "url": "https://en.wikipedia.org/wiki?curid=7080334", "title": "Tin Can Alley", "text": "Tin Can Alley is an inexpensive electronic shooting game for children. It uses infrared technology embedded inside a small plastic pistol or rifle. The objective is to aim at a mark below a selection of small tin cans perched upon a plastic wall. Successfully aiming at the marks below each of the cans causes the can to \"pop off\".\nThe game is based on a popular UK carnival game of the same name, which involves throwing bean bags at tin cans to knock them down. Both the electronic and carnival game are named for Tin Pan Alley, a name for a collection of New York City songwriters and music publishers, as well as the name of the Manhattan location where many of the songwriters and publishers worked.", "Engineering,_Manufacturing": 0.9985921383, "qwen": "Yes"}
{"id": "44136736", "revid": "130596", "url": "https://en.wikipedia.org/wiki?curid=44136736", "title": "Research-based design", "text": "The research-based design process is a research process proposed by Teemu Leinonen, inspired by several design theories. It is strongly oriented towards the building of prototypes and it emphasizes creative solutions, exploration of various ideas and design concepts, continuous testing and redesign of the design solutions. \nThe method is firmly influenced by the Scandinavian participatory design approach. Therefore, most of the activities take place in a close dialogue with the community that is expected to use the tools or services designed.\nPhases.\nThe process can be divided into four major phases, although they all happen concurrently and side by side. At different times of the research, researchers are asked to put more effort into different phases. The continuous iteration, however, asks researchers to keep all the phases alive all the time: contextual inquiry, participatory design, product design, prototype as hypothesis.\nContextual inquiry.\nContextual inquiry refers to the exploration of the socio-cultural context of the design. The aim is to understand the environment, situation, and culture where the design takes place. The results of the contextual inquiry are better understanding of the context by recognizing in it possible challenges and design opportunities. In this phase, design researchers use rapid ethnographic methods, such as participatory observation, note-taking, sketching, informal conversations, and interviews. At the same time as the field work, the design researchers are doing a focused review of the literature, benchmarking existing solutions, and analyzing trends in the area in order to understand and recognise design challenges.\nParticipatory design.\nThroughout the contextual inquiry design researchers start to develop some preliminary design ideas, which would be developed during the next stage—participatory design—in workshops with different stakeholders. The participatory design sessions tend to take place with small groups of 4 to 6 participants. A common practice is to present the results as scenarios made by the design researchers containing challenges and design opportunities. In the workshop, the participants are invited to come up with design solutions to the challenges and to bring to the discussion new challenges and solutions.\nSince one of the main features of the research-based design is its participatory nature, the user's involvement is an integral part of the process. In this regard, participatory design workshops are organized during the different stages in order to validate initial ideas and discuss the prototypes at different stage of development.\nProduct design.\nThe results of the participatory design are analysed in a design studio by the design researchers who use the materials from the contextual inquiry and participatory design sessions to redefine the design problems and redesign the prototypes. By keeping a distance from the stakeholders, in the product design phase the design researchers will get a chance to analyse the results of the participatory design, categorize them, use specific design language related to implementation of the prototypes, and finally make design decisions.\nPrototype as hypothesis.\nUltimately, the prototypes are developed to be functional on a level that they can be tested with real people in their everyday situations. The prototypes are still considered to be a hypothesis, prototypes as hypothesis, because they are expected to be part of the solutions for the challenges defined and redefined during the research. It remains to the stakeholders to decide whether they support the assertions made by the design researchers. Therefore the first prototypes brought to the use of the real people can be considered to be also minimum viable products.\nResearch-based design is not to be confused with design-based research or educational design research. In research-based design, which builds on art and design tradition, the focus is on the artifacts, the end-results of the design. The way the artifacts are, the affordances and features they have or do not have, form an important part of the research argumentation. As such, research-based design as a methodological approach includes research, design, and design interventions that are all intertwined.", "Engineering,_Manufacturing": 0.9999797344, "qwen": "Yes"}
{"id": "19824207", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=19824207", "title": "Sherline", "text": "Sherline is a machine tool builder founded in Australia and currently headquartered in Vista, California, USA. It builds miniature machine tools (microlathes and micromills) and a wide range of tooling to be used on them. Within the miniature segment of the machine tool industry, Sherline is one of the most widely known brands. According to Sherline, their line of OEM accessories (chucks, vises, rotary tables, and so on) is more comprehensive than that of any other builder of machine tools, regardless of machine size.\nSherline tools are often used by hobbyists for making nearly any kind of part that can be machined, as long as it fits within a miniature machine tool's limits of slide travel. Sherline's products are also used by industry. They provide an inexpensive way to build custom tooling using modular components (XY tables, machine slides, etc.).\nSherline's sales are global. Its product line helps to put machine tools in places where traditionally they would be unlikely to go by lowering the threshold for market entry. Its turnkey CNC systems are some of the least expensive CNC machine tools on the market, making it possible for individual hobbyists to enter a market that in past decades was almost entirely industrial.", "Engineering,_Manufacturing": 1.0000033379, "qwen": "Yes"}
{"id": "11276863", "revid": "34993826", "url": "https://en.wikipedia.org/wiki?curid=11276863", "title": "Straight-line mechanism", "text": "A straight-line mechanism is a mechanism that converts any type of rotary or angular motion to perfect or near-perfect straight-line motion, or \"vice versa\". Straight-line motion is linear motion of definite length or \"stroke\", every forward stroke being followed by a return stroke, giving reciprocating motion. \nThe first such mechanism, patented in 1784 by James Watt, produced approximate straight-line motion, referred to by Watt as parallel motion.\nStraight-line mechanisms are used in a variety of applications, such as engines, vehicle suspensions, walking robots, and rover wheels. \nHistory.\nIn the late eighteenth century, before the development of the planer and the milling machine, it was extremely difficult to machine straight, flat surfaces. During that era, much thought was given to the problem of attaining a straight-line motion, as this would allow the flat surfaces to be machined. To find a solution to the problem, the first straight line mechanism was developed by James Watt, for guiding the piston of early steam engines. Although it does not generate an exact straight line, a good approximation is achieved over a considerable distance of travel.\nPerfect straight line linkages were later discovered in the nineteenth century, but they weren't as needed, as by then other techniques for machining had been developed.\nList of linkages.\nApproximate straight line linkages.\nThese mechanisms often utilize four bar linkages as they require very few pieces. These four-bar linkages have coupler curves that have one or more regions of approximately perfect straight line motion. The exception in this list is Watt's parallel motion, which combines Watt's linkage with another four-bar linkage – the pantograph – to amplify the existing approximate straight line movement.\nIt is not possible to create perfectly straight line motion using a four-bar linkage, without using a prismatic joint.\nPerfect straight line linkages.\nEventually, perfect straight line motion would be achieved.\nThe Sarrus linkage was the first perfect linear linkage, made in 1853. However, it is a spatial linkage rather than a planar linkage. The first planar linkage would not be made until 1864.\nCurrently, all planar linkages which produce perfect linear motion utilize the inversion around a circle to produce a hypothetical circle of infinite radius, which is a line. This is why they are called inversors or inversor cells.\nThe simplest solutions are Hart's W-frame – which use 6-bars – and the Quadruplanar inversors – Sylvester-Kempe and Kumara-Kampling, which also use 6-bars.\nThe Scott Russell linkage (1803) translates linear motion through a right angle, but is not a straight line mechanism in itself. The Grasshopper beam/Evans linkage, an approximate straight line linkage, and the Bricard linkage, an exact straight line linkage, share similarities with the Scott Russell linkage and the Trammel of Archimedes.\nCompound eccentric mechanisms with elliptical motion.\nThese mechanisms use the principle of a rolling curve instead of a coupler curve and can convert continuous, rather than just limited, rotary motion to reciprocating motion and \"vice versa\" via elliptical motion. The straight-line sinusoidal motion produces no second-order inertial forces, which simplifies balancing in high-speed machines.\nGallery.\nApproximate straight line linkages.\nParts/links of the same color are the same dimensions.\nPerfect straight line linkages.\nParts/links of the same color are the same dimensions.", "Engineering,_Manufacturing": 0.9983363748, "qwen": "Yes"}
{"id": "11279492", "revid": "958968758", "url": "https://en.wikipedia.org/wiki?curid=11279492", "title": "Travers Tool", "text": "Travers Tool is a distributor of metalworking tools and industrial supplies. The company is based in Flushing, New York, and has distribution branches in or near New York City, Los Angeles, and Duncan, South Carolina.\nTravers offers high speed steel cutting tools, solid carbide cutting tools, carbide indexable cutting tools, blades, abrasives, deburring tools, files, machinery, machine tools, machine tool accessories, measuring tools, inspection instruments, hand tools, power tools, pneumatic tools, welding equipment, fasteners, tooling components, stock materials, Maintenance, Repair and Operations (MRO) products, safety products and equipment, material handling equipment and reference books and software.\nHistory.\nTravers Tool Co., Inc. was started in 1924 by David Trevas. An aspiring young entrepreneur, David borrowed $1000 and asked a New York tool distributor to let him place a telephone on one of the empty desks at the office. After gaining some measure of success, David opened his first metalworking tool distribution office at 5 Court Square in Long Island City, New York. Because many of his customers did not pronounce his last name correctly, David Trevas named his company Travers Tool Co., Inc.\nSeymour Trevas started working for his father in the 1930s. In the 1940s, Travers Tool was honored by receiving the coveted Navy E Award (for excellence) as a navy subcontractor. In the 1950s, Travers Tool relocated to 10-23 Jackson Avenue in Long Island City. In 1967, under the leadership of Barry Zolot, Seymour's son-in-law, the first Travers Tool mail order Master Catalog was created. This move served as a catalyst for significant growth for the company. In 1974, Travers Tool purchased and moved into a , 2-story facility at 25-26 50th Street in Woodside, New York.\nAs business grew throughout the 1980s, Travers Tool moved into a larger facility at 128-15 26th Avenue, Flushing, New York and built a warehouse in Duncan, South Carolina.\nRacing sponsor.\nIn 1994, Travers Tool Company went into sponsoring race cars, first, in the NHRA, when they sponsored Blaine Johnson for his entire career, which lasted from the 1994 Winter Nationals, to the 1996 U.S. Nationals, where Johnson was killed during qualifying, Travers Tool Company has not sponsored a driver since.", "Engineering,_Manufacturing": 0.9987666607, "qwen": "Yes"}
{"id": "11287415", "revid": "34307312", "url": "https://en.wikipedia.org/wiki?curid=11287415", "title": "Backflush accounting", "text": "Backflush accounting is a subset of management accounting focused on types of \"postproduction issuing;\" It is a product costing approach, used in a Just-In-Time (JIT) operating environment, in which costing is delayed until goods are finished. Backflush accounting delays the recording of costs until after the events have taken place, then standard costs are used to work backwards to 'flush' out the manufacturing costs. The result is that detailed tracking of costs is eliminated. Journal entries to inventory accounts may be delayed until the time of product completion or even the time of sale, and standard costs are used to assign costs to units when journal entries are made. Backflushing transaction has two steps: one step of the transaction reports the produced part which serves to increase the quantity on-hand of the produced part and a second step which relieves the inventory of all the component parts. Component part numbers and quantities-per are taken from the standard bill of material (BOM). This represents a huge saving over the traditional method of a) issuing component parts one at a time, usually to a discrete work order, b) receiving the finished parts into inventory, and c) returning any unused components, one at a time, back into inventory.\nIt can be argued that backflush accounting simplifies costing since it ignores both labor variances and work-in-process. Backflush accounting is employed where the overall business cycle time is relatively short and inventory levels are low.\nBackflush accounting is inappropriate when production process is long, and this has been attributed as a major flaw in the design of the concept. It may also be inappropriate if the bill of materials contains not only piece goods but also many parts with more or less variable consumption. If the parts with variable consumption are just a few, like grease or the ink used to print product-labels, the consumed quantities can be assigned to product-independent cost centers at the withdrawal from stores (preproduction issuing) and can eventually be broken down afterwards to specific products or product groups, just like any other indirect or overhead expense. Difficulties maintaining correct inventories on shop floor may also appear if it is usual practice to use alternative materials and/or quantities without needing derogation.\nTherefore, in case of a more complex production system, it is a better approach to use a Manufacturing Execution System (MES) which gathers real production data and is able to deliver exact data to the accounting software or Enterprise resource planning-system where the goods issue is recorded. Thus, variances in consumption, in comparison to the standard bill of materials, are taken into account and assigned to the correct product, production order and workplace. Another advantage of using a MES is that it implements also the Production Track & Trace and the status of work in progress is also known in real time. A disadvantage of MES is that it is not suitable for small series or prototype production. Such type of production should be segregated from the series production and mass production.\nMeaning of backflushing.\nFrom a financial accounting perspective, backflushing is a technique of the perpetual inventory system. Small businesses which have a low variety of items in their inventory still use periodic inventory management. \nA periodic inventory system does not require day-to-day tracking of physical inventory. Purchases, cost of goods sold, and inventory on hand cannot be tracked until the end of the accounting time period when a physical inventory is performed and ending inventory is compared against the sum of beginning inventory and purchases. Cost of ending inventory can be calculated by using the LIFO or FIFO inventory accounting methods, or other less common methods. The end of the accounting period is considered usually the end of each month because otherwise some taxes like the VAT (value added tax) cannot be charged. The monthly stock-taking is the main disadvantage of the periodic inventory system. Another disadvantage is that it requires also monthly a reconciliation between the records of the management accounting and the financial accounting.\nThe main difference between the periodic inventory and the perpetual inventory is that the perpetual inventory does not keep the inventory-balance by using the inventory accounts, instead the entire input is booked immediately on the expense accounts. The principle is the following:\noutput= initial inventory + input - final inventory\nAt the end of the accounting period the inventory is assessed through stock-taking: \ninventory asset account = expense account\nAt the beginning of the accounting period the stock is canceled using the opposite booking: \nexpense account = inventory asset account\nDuring the accounting period any input is booked directly to the expense account. For example, if we buy materials the bookings are:\nmaterial account = supplier account\nmaterial expense account = material account\nAt the end of the accounting period, at the stock-taking the booking will be material account = material expenses account\nDevelopment of more sophisticated computer scanning of inventory has allowed regular use of perpetual inventory systems by companies. According to the generally accepted accounting principles (GAAP), companies can use either perpetual inventory systems or periodic inventory systems. Perpetual inventory management is a system where store balances of inventory are recorded after every transaction. It eliminates the need for the store to close down constantly for inventory stock-taking as perpetual inventory systems allow for continuous stock-taking. Perpetual inventory systems keep a running account of the company's inventory. Perpetual inventory systems involve more record-keeping than periodic inventory systems. Every inventory item is kept on a separate ledger. These inventory ledgers contain information on cost of goods sold, purchases, and inventory on hand. Perpetual inventory management systems allow for a high degree of control of the company's inventory by management. Perpetual inventory management is generally used by companies who have the ability to scan the inventory items.\nIn the context of perpetual inventory, backflushing is automatic accounting of material consumed for production, at the time of confirmation of the production, e.g., when a 4-wheeler automobile is rolled out from assembly line, 4 wheels and tires are deemed to be consumed and issued to production order automatically by way of back flushing by the system. Typically, the assembly line has its own limited stock of materials as work in process. This stock is replenished by transferring materials from a warehouse (store) into the assembly lines own designated location, e.g., a supermarket. At goods receipt the consumed materials are posted automatically from the location designated to the issuing production line. In other words, back flushing refers only to materials which are already withdrawn from the inventory of the warehouse (store) and were delivered to the shop floor. Parts are issued from stores to Work-In-Process inventory, but not based on a job order or for a specific production order. They are issued in quantities estimated to cover requirements of individual work centers and production lines. The issuing may be used to cover a period of time or to fill a fixed—size container. But unlike the traditional approach, also known as \"preproduction issuing,\" where the costs are assigned to the product order at the withdrawal of materials from the stores and after completion of production any excess material is given back to the stores, backflushing delays that until the goods receipt of the finished product or assembly is issued. The remaining quantity of unused material left on the shops is still held in the system as floor stock and so material will not be ordered incorrectly through the Manufacturing resource planning (MRP). By eliminating work-in-process accounts, backflush costing simplifies the accounting process. However, this simplification and other deviations from traditional costing systems mean that backflush costing may not always conform to generally accepted accounting principles (GAAP). Another drawback of this system is the lack of a sequential audit trail. The main advantage of postproduction issuing, not necessarily of backflushing, is that there is no need to update the store balances of inventory at the withdrawal of the materials from stores and recording the excess material through reverse posting (storno). This is especially useful in series or mass production where it is no need to give back excess material to the stores because it is used for the next production order. Even if excess material is given back to stores it does not involve any update to the inventory balance in the financial accounting (stock accounts). It involves only a stock transfer in the inventory management or warehouse management. Only the materials reported as consumed through the method of backflushing or by the MES imply an update to the inventory balance:\nmaterial account = material expenses account\nBack flush is used for materials which are required for the product and have a fixed relationship with it. Depending on how backflushing is implemented in the accounting software being used and depending on organizational rules, the back flushing may create error records which need to be analyzed by someone in charge for the cost accounting. One possible reason for the creation of these error records can be that there is no sufficient book inventory available in the designated back flushing location (shop floor). By simply deleting the error record, without working it out, could mean that the costs are not assigned correctly to products and/or even that the expenses in the financial accounting (inventory accounts) are not being recorded. The error record as such, is not a specific consequence of using back flushing. It may exist also when a MES system is being used when no back flushing is needed. The reason for this is that any error in transmitting and/or interpreting the data being sent by the MES system to the ERP system is consigned and needs to be worked out. When using back flushing, any scrap, material usage variance (using more or less than specified in the BOM) or substitution must be reported separately in order to maintain acceptable inventory accuracy. These are typically implemented as unplanned transactions. The downside of unplanned transactions is that they are prone to error. Unplanned inventory transactions must be eliminated and replaced creatively with planned transactions because even a very low percentage of misreported transactions will take inventory accuracy quickly to an unacceptable level. That is why the usage of backflushing is recommended only if 2 conditions are met: low I/O Variation and low Production Lead Times. Without low part I/O variation through low scrap, non-standard usage, and substitution, system inventory levels become unreliable. The exception transactions just cannot come through quickly or accurately enough to tame the beast. Loss of trust in the system occurs. Without short manufacturing lead times, components get moved into production but don't get relieved right away from the ERP inventory. This leads to confusion. Evident discrepancies between physical and system inventory counts cause frustration and lack of trust in the system. Without accurate and timely inventory levels, internal production plans and external purchase orders cannot be scheduled effectively, leading to inventory shortages and excess inventory. Inventory shortages cause disruptions to the manufacturing schedule, forcing additional setups, forced substitutions, overtime, premium freight charges, missed shipments and lost capacity. Excess inventory increases obsolescence and consumes precious cash flow and shelf space. Both excess inventory and shortages can indirectly lead to poor quality. A plant cannot cycle-count its way to accurate inventories. Cycle counting is not timely enough to be of benefit. And cycle counts are more likely to introduce errors than to correct them.\nAlternatives to backflushing.\nIf the nature of a manufacturing process is such that component usage variation is natural and unavoidable, and/or production lead times are long, an ERP implementation design that entails a different methodology than backflushing from the shop-floor stock is required. There are two strategies used to deliver materials to the shop floor: Push and Pull, see Push–pull strategy. Depending on which strategy is being used and depending on how it is implemented, backflushing can be eliminated.\nAlternatives to Backflushing when using the Push-strategy\nThe traditional way of issuing consumed materials is by using dual issues and returns against work orders. Components are counted when issued to a production order from Stores when the production order is opened. Produced parts and leftover components are counted when returned to stores when the work order is closed. In conjunction with a tightly controlled material Stores with discrete storage places, this can deliver very high inventory accuracy without the need for additional transactions to report scrap, material substitution, and non-standard usage separately. This obviously requires more transactions than backflushing. But these can be automated in a variety of ways, especially since most transactions take place in a limited area (Stores) and not throughout the plant. Accountability for component usage and operator time/efficiency at the work-order level by operator/shift/cell is greatly increased in this method over backflushing. Work orders also deliver higher lot-control quality measurement potential, substitution management (through a modified work-order BOM) and higher part and customer container bar-coding accuracy. The shop-floor stock in this case uses a discrete storage bin, identical to the number of the production order but no backflushing is required when the produced parts are counted. Leftover components are returned to the store and all the components from the discrete shop-floor storage bin are issued against that production order (postproduction issuing), in a similar way like backflushing, but not based on the bill of materials (BOM) but on the real stock which was consumed (transferred from the stores) for that particular production order.\nThe downside of this method is that it may not be suited for a more complex and repetitive production because it requires perfect contention of the WIP (raw materials and assemblies) on the shop floor: the materials issued to a production order shouldn't interfere with another production order or the next production order of the same kind. This can be done only if all work-steps required to complete the production order are limited more or less to a single workplace. That is why this kind of approach can be implemented for complex products only by using the push strategy. Push strategy means that a complex finished product is divided into many smaller assemblies and even assemblies may contain smaller assemblies and so on. All these assemblies will receive their own production order. These production orders are usually created automatically by the MRP\\ERP - system. The ERP system uses Manufacturing resource planning (MRP) for the planning of production orders. Usually only the production planning for the finished product is done manually by the production planner, the assemblies are planned automatically based on backward scheduling. This is especially useful if the assemblies are being produced in another production line, workshop or plant. The downside of MRP and Push strategy is that it usually leads to larger stocks in the supply chain. That is why Push is regarded as the opposite of lean production because lean production involves the Pull strategy which means that any part should only be produced if there is a certain demand for it and therefore WIP will be small. Push strategy is when MRP is used also to schedule production orders for semi-finished products (assemblies) based on the forecasted demand of the finished product. These assemblies are put into stores without any reference to a certain production order of the finished product. The finished product may not even have had production orders released at the time the assembly was delivered to the store. That is why using MRP to schedule the execution of production orders is by definition a push system because releases are made according to a master production schedule without regard to system status. Hence, no \"a priori\" WIP limit exists. However MRP can be designed in such a way that it has an explicit WIP constraint. That means that assemblies are not produced further if a certain level of inventory is reached. MRP with a WIP constraint can be regarded as a pull system. However, even if a WIP constraint is implemented, Push-strategy generally means that the time, needed from the first operation or assembly until the finished good is obtained, is much longer as opposed to pull-strategy. This is due to the lead-times needed for each assembly and can be analyzed by using a technique called Value stream mapping. There is usually also much more handling: putting the assemblies into the stores, picking the assemblies from stores to the next production step (order) which uses the assembly to make another assembly or finished product. In reality, most firms use both strategies. For example: you could use MRP (push) without WIP constraint to schedule assemblies that are produced in another workshop, plant or external supplier and Kanban (pull) in your own plant. You can also use Kanban to schedule the assemblies in another workshop or plant, but it is usually not done when these assemblies are produced on large machines because with MRP the demand of several days can be comprised in bigger lot sizes of production orders of similar type in such a way that the workshops own scheduling system (MES) is then able to use the available machine-capacity better by bringing the production orders into an optimal sequence using suitable algorithms. This is usually the case when the machines are expensive, their number is relatively small and they have big output-capacities and setup time is expensive. Implementing Kanban in such a case would require to use a bigger number of smaller\\cheaper machines, dedicated to certain production lines, in order to react more flexibly to the demand. Another requirement would be that the frequency of transports from\\to that plant to be higher and the distance to that plant to be relatively small. These requirements however, cannot be accomplished in each case. On the other side, the workshop (supplier) which manufactures the assemblies may very well use a push strategy or a pull-strategy for delivering the needed materials to each of its own machines.\nAs described above, this alternative to backflushing has a self-correcting property: the shop-floor stock is always related to a certain production order, onto which all the consumed materials were actually issued. On the other hand, backflushing by its very definition can never be self-correcting and should only be used when corrections are rarely needed. An objection can be made with the above described alternative that scrap is not reported with a reason code, or broken out separately from other forms of non-standard usage. But how accurate is scrap reporting in an environment without inventory accuracy? Better to settle for inventory accuracy and worry about scrap later as a separate issue. Option: implement a separate scrap analysis protocol unrelated to inventory transactions. Scrapped parts are segregated for subsequent inspection, quality data recording and possible rework. In both cases, scrapped parts are already removed from inventory at the end of the manufacturing cycle (presumably by returning fewer components to stores). Therefore, an inventory transaction is only needed when parts are deemed acceptable upon inspection, or after a rework operation is performed. Scrap reporting can also be done by using data from the Process control system and/or Manufacturing Execution System. Usually such a system exists to some degree in any firm, even if it is not called PCS or MES and even if it is used eventually only for keeping data regarding personnel performance and piecework, as a basis for calculating the salary of the workers. Such a system could be extended so that each worker reports also the scrapped parts.\nMore technical requirements like Production Track & Trace, Overall Equipment Efficiency, Production Performance analysis or displaying production progress of a production order in real time should always be implemented as part of an MES. It is a bad approach to implement such systems more or less just for the sake of inventory accuracy. Inventory accuracy should be attained through much simpler means, as described above and should not depend for example on the quality of the scrap reporting. The same is true the other way around: for example if you need Production Track & Trace (which components belonging to which lots were incorporated into a product with a given serial number) you shouldn't rely solely on the components issued as consumed for a specific production order, especially when using backflushing that would be a bad idea.\nThe same is true for production scheduling: an ERP\\MRP can be used to schedule production orders (to establish deadlines for their delivery) as well as to schedule goods receipts from the suppliers. It is also a very useful tool to offer data for internal usage about medium to long-term demand and\\or planning or a forecast for external suppliers based on BOM explosion. But ERP\\MRP is usually not very useful for scheduling operations on the shop-floor. A production planner using ERP may oversee total gross-capacity demand for all or for a certain type of operation but may not see bottlenecks on individual machines or workplaces. It is the job of the scheduling system (MES) to dispatch the production orders received from the ERP to individual machines\\work places. When lean production is used (Pull), see next chapter, the production order received from the ERP usually refers to a finished product or to a more complex assembly. In this case, the scheduling system is even more important because it has to dispatch parts of the production order to individual work-places.\nAlternatives to Back flushing when using the Pull-strategy\nPull strategy means that work centers request the materials needed for a specific production order from the store or from an upstream workplace (demand driven). Usually this means that semi-finished products are produced for a specific production order of the finished product and therefore stocks held in the supply chain are better managed (usually smaller). This can be accomplished by using Kanban. Kanban is essentially a production scheduling system. It can be used together with a Process control system to make a Manufacturing Execution System. A Process control system gathers data from the work places where the production order is executed. It receives the individual workloads assigned by the scheduling system to individual work places. The purpose of the scheduling system is to optimize the usage of resources. For scheduling the production of individual workplaces, Kanban can be used solely or a more complex optimization software is necessary. Usually a scheduling system based on an optimization software is necessary if the production is executed on machines and it is non-trivial to decide on which machine a specific production order should be executed in order to use resources optimally. Such a type of scheduling problem is known as Job shop scheduling or Flow shop scheduling. Job shop scheduling means that each production order needs to be executed only on one machine for completion and the problem is to get the optimal sequence of orders for a specific machine and, in case that we have several machines that are able to execute the same order, to assign the order to the machine that has available resources. Flow shop scheduling means that a production order has to pass several types of work-centers (machines) in a predefined order. This is a more complex problem than \"job shop scheduling\" because after completion of one work-step, the system has to assign an available machine for the next type of operation until all operations for a given production order are completed. Regardless of the type of scheduling problem the algorithm needed to accomplish this task has n! complexity (n factorial). There is a well known similar type of problem called the Travelling salesman problem. Only very small problems of this kind can be solved using Brute-force search. A simple example: Let's assume that we have only one machine and 20 production orders. Due dates have no importance. We want to put these 20 production orders in the optimal sequence so that the overall setup time is minimal. All setup times needed to switch from one order to the other are known and may be different: setting the machine up from order1 to order2 may need 1 minute, but from order 2 to order1 the time may be different from 1 minute. So we have permutations of size 2 for 20 objects which equals 320 distinct pairs of setup costs. But there are 20!= 2,432 * 10^18 distinct possibilities for putting the 20 orders in a sequence. Enumerating each possibility is not feasible because there are 2,432 * 10^18 possibilities. Therefore, Heuristic algorithms are used for solving problems of this kind. These algorithms do not guarantee to find the optimal solution, but they usually find a solution in the vicinity of the optimal solution in a reasonably short period of time. So the meaning of a MES is to be able to use such heuristic algorithms in order to fulfill the business policy. The business policy defines how the antagonistic restrictions are weighted, which of them are more important. These antagonistic restrictions are: delivery deadlines, machine setup time and machine usage. The scheduling system knows everything about the capabilities of the machines, the available tools and so on, and it can therefore make an optimal decision, which work-place (machine) should execute which part of the production order and when. Of course the operator should be able to refuse the order if something unpredictable has happened (a tool is missing or not operational etc.) and the system should be able to reschedule the order automatically or with the aid of a production planner or supervisor. A MES has to be a dynamic system which can react to the real and unpredictable events.\nIn such an environment, where the production order received form the ERP\\MRP software is scheduled using a MES or Kanban and the materials are assigned to the shop floor at the withdrawal from stores, there is no need for using backflushing. The materials are usually issued from the stores to a supermarket on the shop floor without being related to a specific production order but in the amount needed to cover the demand of the already released production orders. This amount is dynamic, and we call it \"Kanban-quantity.\" It should be calculated in real-time by the MES. The supermarket itself can be regarded as a derogation from the principles of lean production, especially from those of the \"One Piece Flow\" concept, because it represents work in progress, WIP, which is not yet assigned to a specific production order being executed or which has been already released for production. The stock in the supermarket is already issued to the shop floor stock. The usage of a supermarket is usually necessary when not all of the individual work steps which are needed for the completion of the production order have the same execution time and therefore a small buffer is needed to avoid that one workplace is waiting for an upstream workplace to complete work. This buffer is usually maintained using 2 containers in the supermarket in which such kind of assemblies are stored. If none of the containers is empty, no further assemblies are being produced. If one of the container is empty, the remaining container is swapped with the empty one (FIFO) and production of the assembly is resumed according to the kanban-quantity computed by the MES. Another purpose of the supermarket is that it enables a quick replenishment of the workplaces with the needed raw-materials without the necessity for taking these materials from the store for each production order as opposed to the above described push-strategy where every material has to be issued to every production order at the withdrawal from stores. In other words, the quantity of any assembly or raw-material being stored in the supermarket is strictly limited, there is an explicit WIP constraint. Usually the supermarket is placed in the proximity of the work-places, so that the work-places have quick access to the needed materials. Every material has its own storage location in the supermarket (coordinates) so that it can be easily located when needed. The materials to be consumed are assigned by each workplace to the production order either by scanning them at the withdrawal from the supermarket (preproduction issuing) or by reporting them through the MES and Process control system (postproduction issuing).\nUsually the first approach (scanning at the withdrawal) is used for materials which are piece goods. If the materials are not piece goods (bulk material, yard ware), then the workplace has to report the consumed quantities after it has finished its job on a particular production order. If a process control system is being used then the process control system will report the consumed materials directly to the ERP\\MRP- System or to the MES and then the MES reports to the ERP. If no process control system is used, usually the case when manual work is being done, the consumed quantities have to be reported manually from every workplace by using a terminal (scanner, PC, etc.). Usually, when using bulk materials, the workplace reports the consumed quantity on the level of the handling unit (HU). A handling unit is a number assigned to the carton, pallet or any other kind of unitized packaging. So the handling unit is assigned to the workplace, the consumed quantity from that HU is issued and the HU, if no longer needed is put back to the supermarket. As a direct consequence a partial withdrawal from that handling unit is issued as consumed also in the ERP\\MRP system. Any physically empty HU is reported using a distinct transaction. That means that any residual book inventory quantity that may exist in the ERP system, assigned to the shop floor and to that specific HU is reported as consumed and issued to a distinct cost center. Inversely, should a workplace report a consumption from a HU that has no book inventory in the shop-floor stock (is already empty in the ERP system), an error is generated as a backlog in issuing the consumed materials, see chapter \"Meaning of backflushing.\" What kind of unplanned transactions are used to handle this error is a question of internal policy of every firm.\nThe reason why residual book inventory may exist in the MRP/ERP system may have multiple causes. A few of them are:\n- the quantity in the original packaging was not completely exact (e.g. the supplier indicated a quantity of 10000 meters per coil, but some coils had only 9500 meters);\n- the workplace has consumed some materials for adjusting the machine without being able to report that quantity exactly;\n- the operator has omitted to assign a new handling unit to the workplace or has assigned the false handling unit. Such errors can be avoided if the system has a good data validation. For example, the machine does not start processing the job until all handling units required for that job are assigned to the work place or machine.\nIt is very important to design the interface between the MES and the MRP\\ERP properly: the reporting of the consumed quantities has to be processed consistently, in the right order, in other words all the recorded/reported consumptions from a handling unit should be issued in the ERP before issuing the handling unit as empty. Otherwise a large number of false errors would get into the error-backlog because the book inventory is already zero as a consequence of issuing the handling unit as being empty before issuing all the consumption which refer to that specific handling unit.\nThese two alternatives to backflushing based on the pull-strategy (preproduction issuing/postproduction issuing) have also a self-correcting property: real quantities are reported from each workplace (not based on the bill of materials) and each unitized packaging (handling unit), when empty, is reported as empty and any residual book-inventory on the shopfloor is discarded.", "Engineering,_Manufacturing": 0.9992733598, "qwen": "Yes"}
{"id": "1985954", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=1985954", "title": "Poka-yoke", "text": " is a Japanese term that means \"mistake-proofing\" or \"error prevention\". A poka-yoke is any mechanism in a process that helps an equipment operator avoid (') mistakes (') and defects by preventing, correcting, or drawing attention to human errors as they occur. The concept was formalized, and the term adopted, by Shigeo Shingo as part of the Toyota Production System.\nEtymology.\nPoka-yoke was originally \"\", but as this means \"fool-proofing\" (or \"idiot-proofing\") the name was changed to the milder \"poka-yoke\".\nPoka-yoke is derived from \"\" , a term in shogi that means avoiding an unthinkably bad move.\nUsage.\nMore broadly, the term can refer to any behavior-shaping constraint designed into a process to prevent incorrect operation by the user.\nA simple poka-yoke example is demonstrated when a driver of the car equipped with a manual gearbox must press on the clutch pedal (a process step, therefore a poka-yoke) prior to starting an automobile. The interlock serves to prevent unintended movement of the car. Another example of poka-yoke would be the car equipped with an automatic transmission, which has a switch that requires the car to be in \"Park\" or \"Neutral\" before the car can be started (some automatic transmissions require the brake pedal to be depressed as well). These serve as behavior-shaping constraints as the action of \"car in Park (or Neutral)\" or \"foot depressing the clutch/brake pedal\" must be performed before the car is allowed to start. The requirement of a depressed brake pedal to shift most of the cars with an automatic transmission from \"Park\" to any other gear is yet another example of a poka-yoke application. Over time, the driver's behavior is conformed with the requirements by repetition and habit.\nHistory.\nThe term poka-yoke was applied by Shigeo Shingo in the 1960s to industrial processes designed to prevent human errors. Shingo redesigned a process in which factory workers, while assembling a small switch, would often forget to insert the required spring under one of the switch buttons. In the redesigned process, the worker would perform the task in two steps, first preparing the two required springs and placing them in a placeholder, then inserting the springs from the placeholder into the switch. When a spring remained in the placeholder, the workers knew that they had forgotten to insert it and could correct the mistake effortlessly.\nShingo distinguished between the concepts of inevitable human mistakes and defects in the production. Defects occur when the mistakes are allowed to reach the customer. The aim of poka-yoke is to design the process so that mistakes can be detected and corrected immediately, eliminating defects at the source.\nImplementation in manufacturing.\nPoka-yoke can be implemented at any step of a manufacturing process where something can go wrong or an error can be made. For example, a fixture that holds pieces for processing might be modified to only allow pieces to be held in the correct orientation, or a digital counter might track the number of spot welds on each piece to ensure that the worker executes the correct number of welds.\nShingo recognized three types of poka-yoke for detecting and preventing errors in a mass production system:\nEither the operator is alerted when a mistake is about to be made, or the poka-yoke device actually prevents the mistake from being made. In Shingo's lexicon, the former implementation would be called a \"warning\" poka-yoke, while the latter would be referred to as a \"control\" poka-yoke.\nShingo argued that errors are inevitable in any manufacturing process, but that if appropriate poka-yokes are implemented, then mistakes can be caught quickly and prevented from resulting in defects. By eliminating defects at the source, the cost of mistakes within a company is reduced.\nA methodic approach to build up poka-yoke countermeasures has been proposed by the Applied Problem Solving (APS) methodology, which consists of a three-step analysis of the risks to be managed:\nThis approach can be used to emphasize the technical aspect of finding effective solutions during brainstorming sessions.\nBenefits of poka-yoke implementation.\nA typical feature of poka-yoke solutions is that they don't let an error in a process happen. Other advantages include:", "Engineering,_Manufacturing": 0.999969244, "qwen": "Yes"}
{"id": "1791536", "revid": "44903564", "url": "https://en.wikipedia.org/wiki?curid=1791536", "title": "Dynamic packaging", "text": "Dynamic packaging is a method used in package holiday bookings to enable consumers to build their own package of flights, accommodation, and car rental instead of purchasing a pre-defined package. Dynamic packages differ from traditional package tours in that the pricing is always based on current availability, escorted group tours are rarely included, and trip-specific add-ons such as airport parking and show tickets are often available. Dynamic packages are similar in that often the air, hotel, and car rates are available only as part of a package or only from a specific seller. The term \"dynamic packaging\" is often used incorrectly to describe the less sophisticated process of interchanging various travel components within a package, however, this practice is more accurately described as \"dynamic bundling\". True dynamic packaging demands the automated recombination of travel components based on the inclusion of rules that not only dictate the content of the package but also conditional pricing rules based on various conditions such as the trip characteristics, suppliers contributing components, the channel of distribution, and terms of sale. Dynamic packages are primarily sold online, but online travel agencies will also sell by phone owing to the strong margins and high sale price of the product.\nDynamic packaging is dynamic at several levels. Firstly, inventory is sourced dynamically, meaning the dynamic packaging solution will source flights, accommodation and car rental components for the package in real-time. Secondly, these components are dynamically combined into packages. Thirdly, the package is dynamically priced and is usually given an opaque total price.\nBenefits.\nDynamic packages are normally given a single, opaque price, meaning the wholesaler's cost of the individual components is hidden from the consumer. The wholesaler often obtains special package-only cost rates for travel components, such as negotiated fares for flights or special package rates for accommodation or car rental. These cost prices are typically significantly lower than the cost prices suppliers offer for the same products if they were to be sold as single components. Hence, the wholesaler will be able to offer the consumer a combined saving for the dynamic package, without reducing his own margins.\nOpaque pricing of dynamic packages hide the price of the included components. This has several benefits. Suppliers of travel products often impose a minimum selling price for their products. For instance, a hotel might give the wholesaler a room at cost price \"X\", but on the condition that the room is not sold for less than \"Y\" (hotels do this to prevent wholesalers from competing with themselves). With dynamic packaging, the customer is not presented with the room price, only the overall package price, so hotels typically allow the wholesaler to discount the (hidden) price of the hotel more.\nOpaque pricing also has benefits for airlines. Airlines tend to increase their fares the closer you get to the departure date, even if there are many available seats. This is to \"train\" the consumers to book early, making it easier for the airline to do proper revenue management. If airlines were to dump their fares if a flight failed to fill up, then this would train the customers to wait until very close to departure before booking. This would make it virtually impossible for an airline to manage their fares (fares could then only be determined based on historical data and not based on current demand). Dynamic packaging allows an airline to get rid of distressed inventory at discounted fares, as the discounted fare is effectively hidden from the consumer.\nApplication.\nDynamic packaging has experienced extensive integration across the travel industry, as many tour operators and online travel agencies (OTAs) have implemented these solutions to address the growing demand for personalized travel experiences. This has led to the development of sophisticated algorithms and software systems that can source, combine, and price travel components in real-time, providing greater flexibility and customization for travelers. Travel providers such as Guide to Europe offer travelers the flexibility to build their own package tour, combining flights, accommodations, and activities based on their preferences and budget.\nThe real-time nature of dynamic packaging enables travel providers to offer attractive last-minute deals by capitalizing on distressed inventory, such as unsold flight seats or hotel rooms. Dynamic packaging also enables travel providers to cater to specific market segments, such as adventure travelers, luxury travelers, or budget-conscious travelers, by offering customized packages that cater to their unique needs and preferences. Additionally, travel providers can leverage dynamic packaging to offer customized packages and exclusive deals to their loyalty program members, further enhancing customer loyalty and engagement.\nFuture outlook.\nAs technology continues to advance and consumer preferences evolve, dynamic packaging is expected to play an even more significant role in the travel industry. Some potential future developments include greater personalization through artificial intelligence (AI), which could further enhance the personalization capabilities of dynamic packaging by analyzing user data and preferences to recommend highly tailored travel packages. Advancements in data analytics and pricing algorithms may lead to more accurate and sophisticated dynamic pricing models, allowing travel providers to optimize revenue and offer even more competitive deals to travelers. The integration of dynamic packaging with emerging technologies, such as virtual reality or augmented reality, could enable travelers to preview their customized travel experiences before booking, further enhancing the personalization aspect of dynamic packaging.\nPreconditions.\nDynamic Packaging is also often misunderstood since it requires that the provider of Dynamic Packaging be a wholesaler, who must also issue tickets, vouchers or other redeemable coupons in order to become a Dynamic Packager. Without an inventory management system, and a ticket, coupon or voucher issuing system to make the prices of the individual components appear as one price to the consumer and allow each travel service provider to know what rate to accept or charge the traveler; dynamic packaging does not work. Many travel retailers have mistakenly assumed they could provide dynamic packaging without an inventory management system, mark-up engine with business rules and a ticket issuing and resolution system.\nThe wholesaler must either directly control the inventory that is combined into packages or buy the package components up-front from other travel suppliers. This implies that dynamic packages (as with static packages) are always pre-paid by the customer.\nThe wholesaler would typically also require special discounted fares/rates from the travel suppliers. For car rental, the supplier (car rental company or intermediary) should ideally supply their price based on calendar days rather than hour-by-hour. Calendar day rates reduce the number of vehicle availability/pricing scans the wholesaler must make. For packages that include flights, the outbound arrival and return departure date/times determine the car rental pick-up and drop-off date/times. If car rental rates were by the hour they would differ for each flight option, hence the wholesaler would have to issue a vehicle availability search for each available flight, while with 24-hour rates one single vehicle availability search is enough to cater for all flight options.", "Engineering,_Manufacturing": 0.9706215262, "qwen": "Yes"}
{"id": "1793873", "revid": "21280117", "url": "https://en.wikipedia.org/wiki?curid=1793873", "title": "Soldering gun", "text": "A soldering gun is an approximately pistol-shaped, electrically powered tool for soldering metals using tin-based solder to achieve a strong mechanical bond with good electrical contact. The tool has a trigger-style switch so it can be easily operated with one hand. The body of the tool contains a transformer with a primary winding connected to mains electricity when the trigger is pressed, and a single-turn secondary winding of thick copper with very low resistance. A soldering tip, made of a loop of thinner copper wire, is secured to the end of the transformer secondary by screws, completing the secondary circuit. When the primary of the transformer is energized, several hundred amperes of current flow through the secondary and very rapidly heat the copper tip. Since the tip has a much higher resistance than the rest of the tubular copper winding, the tip gets very hot while the remainder of the secondary warms at a much slower rate. An additional secondary winding is often used to power a pilot lamp which illuminates the workpiece.\nThe soldering gun is useful when soldered joints must be made intermittently. A constant-heat device has to be set in a safe place when powered but not actually in use, to prevent damage or injury. The fast-switching gun cools quickly enough to be set down a few seconds after use.\nApplications.\nSoldering guns are used where more heat is needed than from the lower-power soldering irons. They can be used for heavy electrical connections, stained glass assembly, and light sheet-metal work. Typical soldering guns are rated at 100 to 240 watts power. A gun may include a two-stage trigger to give two heat settings. Tips designed for cutting and shaping plastic are available; soldering guns for general home use may be supplied with a kit of different tips.\nThe temperature of the soldering tip is regulated manually by holding the button until the solder melts, and then releasing it. When the solder is about to start solidifying, the button is pressed again, and so on. An experienced worker develops the skill to regulate the temperature according to need. Because the temperature of the tip is not automatically regulated, use of a soldering gun for joints on printed circuit boards can result in too much heat supplied to the joint, damaging the circuit board.\nThe copper tip slowly dissolves in the solder and eventually has to be replaced. The soldering gun generates an electromagnetic spike when the button is released, which can be a problem for electromagnetically-sensitive devices. The spike can be seen when a high-efficiency LED is soldered, as the LED flashes. The heavy magnetic field produced by the tip can attract and hold small ferrous metal pieces (screws, etc.).\nHistory.\nPistol-grip electrically-heated soldering tools had been used since the 1920s. In 1941 Carl E. Weller invented and later obtained for a transformer-based soldering tool which heated and cooled rapidly, essentially as described in this article. Weller formed a company to manufacture and sell his invention commercially in 1946. The Weller company was bought in 1970 and merged into the Cooper Industries group, retaining the Weller brand for soldering equipment.", "Engineering,_Manufacturing": 0.9988029003, "qwen": "Yes"}
{"id": "48770911", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=48770911", "title": "Procons", "text": "Procons Oy Ab is a Finnish company specialized in sheet metal roll forming and subcontracting. Main business areas include sliding door profiles, bike mudguards and stays, profiles for the electrical and mining industries as well as sheet metal products. The company was founded in 1934 and is located in Malax, Finland.\nHistory.\nThe company that would become Procons Oy Ab was Waasan Vanne, founded in 1934 in Vikby, Finland. It developed and manufactured bicycle mudguards, luggage carriers and rims. In the 1990s, the company shifted its focus to the production of metal profiled products and built automated profiling production lines for thin sheet metal. In 2002, Leif Sandqvist, a former regional executive at Bosch, bought Waasan Vanne. He relocated the company to nearby Malax, his hometown, the next year and, in 2011, reincorporated it as Procons Oy Ab.\nProducts.\nBicycle parts.\nProcons is one of Europe's largest manufacturers of bicycle fenders and stays with a production of about 750,000 fenders per year. The product range consists of various models and brands that are produced mainly from 0.5 mm sheet metal in a fully automated line.\nOther.\nThe company acts as a subcontractor providing roll-form manufacturing of various profiles for heavy industry clients. It also develops and manufactures components for the assembly of sliding doors. Other business areas include eccentric pressing, welding, and assembly.", "Engineering,_Manufacturing": 0.9993886948, "qwen": "Yes"}
{"id": "14726567", "revid": "19404073", "url": "https://en.wikipedia.org/wiki?curid=14726567", "title": "List of build automation software", "text": "Build automation involves scripting or automating the process of compiling computer source code into binary code. Below is a list of notable tools associated with automating build processes.\nBuild script generation.\nThese \" generator\" tools do not build directly, but rather generate files to be used by a \"native\" build tool (as the ones listed in the previous two sections).\nMeta-build.\nA meta-build tool is capable of building many different projects using a subset of existing build tools. Since these usually provide a list of packages to build, they are also often called package managers.", "Engineering,_Manufacturing": 0.9995009899, "qwen": "Yes"}
{"id": "42801684", "revid": "40561892", "url": "https://en.wikipedia.org/wiki?curid=42801684", "title": "Rockman Industries", "text": "Rockman Industries, formerly Rockman Cycles limited, is an Indian auto components manufacturer, based in New Delhi, India. The company is one of India's largest auto component manufacturers. Rockman Industries is primarily engaged in the manufacturing of aluminum die casting components, machined and painted assemblies, auto chains and parts. In January 2017, Rockman Industries entered the carbon composites sector with the acquisition of Moldex Composites, a UK-India carbon composite design and manufacturing company. Rockman was founded in 1960 and is led by Suman Kant Munjal, Chairman and Ujjwal Munjal, Managing Director.\nHistory.\nA part of the Hero Group, Rockman Industries (formerly Rockman Cycles limited.) was set up in 1960 and started to manufacture bicycle chains and hubs for Hero Cycles. In 1999, it diversified into high pressure aluminium die cast components and automotive chains for Hero MotoCorp (Erstwhile Hero Honda). In 2005 it closed the bicycle chains and hubs business and from November 2005, is only manufacturing die casting components and auto parts. In 2008, Rockman Industries set up a new auto components plant in Uttaranchal. In February 2014, Rockman Industries acquired Sargam Die Casting company and started its new facility at Bawal (Haryana). In January 2017, Rockman Industries acquired a majority stake in Moldex Composites to enter the aerospace, motorsport and high-end auto component manufacturing space. In 2019, company inaugurated two new plants at Vadodara and Tirupati. In Tirupati plant company is manufacturing four wheeler alloy wheels.\nManufacturing units.\nRockman Industries has eight manufacturing plants at Ludhiana, Haridwar, Chennai , Bawal, Surat, Vadodara and Tirupati. In Ludhiana they have two plants, one for chains and the other for aluminium die casting products. All other locations manufacture die casting components. Surat's unit is manufacturing advanced composites parts.\nCustomers.\nRockman Industries supplies its products to Hero MotoCorp and various global automotive companies including: TVS, Honda, Royal Enfield, Revolt, Ather, Hyundai, Kia, Ford Motor, Mahindra, Tata, Bosch, Stanadyne, Dana, Denso, Nemak, PSA AVTEC, KSP Automotive, Continental, Magna, Hanon System, Wabco, Mando, Getrag, BorgWarner, iwis and others.", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "42835913", "revid": "1152069119", "url": "https://en.wikipedia.org/wiki?curid=42835913", "title": "Component placement", "text": "Component placement is an electronics manufacturing process that places electrical components precisely on printed circuit boards (PCBs) to create electrical interconnections between functional components and the interconnecting circuitry in the PCBs (leads-pads). The component leads must be accurately immersed in the solder paste previously deposited on the PCB pads. The next step after component placement is soldering.\nPlacement process.\nBasic placement sequence generally includes: board indexing, board registration, fiducial vision alignment, component pick-up, component centering/vision inspection, component placement and board indexing. Component pick-up, component centering/vision inspection, component placement are repeated for each component. Sometimes, adhesive dispensing and on-line electrical verification are also included in the sequence.\nThrough the process of board indexing, the stencil-printed PWB is loaded to the appropriate position. Fiducial marks, also known as fiducial markers, provide common measurable points for all steps in the assembly process. There are many types of fiducials. Global fiducials are used to locate the position of all features on an individual printed circuit board. When multiple boards are processed as a panel, the global fiducials may also be referred to as panel fiducials if used to locate the circuits from the panel datum. Local fiducials are used to locate the position of an individual land pattern or component that may require more precise location, such as a pitch QFP.\nBoard is located by identify global fiducials on the PWB. Then the feeders pick up and center the components at a known distance from the component. Higher placement accuracy requires help from local fiducials visualized by optical or laser sensors. Vacuum pickup head removes components from feeders. In the end, the component is placed at the correct X, Y and theta location with all leads ion the correct pads in contact with solder paste. The PWBs with all components correctly placed will then move to the reflow process.\nThere are three primary attributes that shall be considered in the component placement system: accuracy, speed and flexibility. Accuracy involves the aspects of resolution, placement accuracy and repeatability. Speed involves the aspects of equipment placement rate, de-rating strategy and production through-put. Placement rate is determined by machine type and the distance between components on a board. Flexibility involves the aspects of component variety, number of feeders and PCB size range.\nTypes of pick and placement machines.\nA pick and placement machine is a robotic style machine that places some variety of types of components. It includes features such as: component pickup feeder locations, vacuum pickup, vision system, automatic component realignment, repeatable placement accuracy, and transportation system for PCBs.\nThe pick and place machine is often the most important piece of manufacturing equipment for placing components reliably and accurately enough to meet throughput requirements in a cost-effective manner. Typically, surface mount pick and place equipment, including a full complement of feeders constitute about 50% of the total capital investment required for a medium volume surface mount manufacturing line.\nThere are two major types of pick and placement machine:\nChip shooter.\nChip shooters are being used for as much as 90% of the most common components, like passives and small actives. Chip shooters are fast (20,000 to 80,000 per hour, can be as fast as 100,000 per hour) with a relatively low accuracy (generally 70 μm). As a result, chip shooters are not used for placing active components, which require better accuracy. There are three major types of chip shooters: stationary turret, overhead gentry, and revolver head.\nFlexible placer.\nComparing to chip shooters, flexible placers are slow (6,000 to 40,000 per hour) with a high accuracy (as low as 25 μm). As a result, flexible placers are being used to place complex and high I/O active components like QFPs as higher performance I/O components generally require higher accuracy. There are three major types of flexible placer: overhead gantry, revolver head and split-axis. Chip shooters and flexible placers are typically combined to use and they can take account of nearly 65% of the total assembly line cost.\nTypes of placement heads.\nOverhead gantry.\nOverhead gantry-style positioning system's placement head is mounted on a gantry beam (X-axis). During the sequence, the beam moves perpendicular to the direction of the placement head movement, which offers two degrees of freedom (X and Y alignment) in a plane parallel to the machine table. The PCB and feeders keep stationary during placement. The PCB is located on the table by identifying global and local fiducials through a vision system. This placement head moves along the axis beams to pick components from a feeder, and then moves into position to place the components. A vacuum nozzle on the placement head moves up and down vertically to provide Z-axis and rotates in the horizontal plane to provide theta angular alignment. Sometimes a secondary vision system is also applied to check the correctness and alignment of the components after pick-up and before placement. As the PCB and feeders remain stationary in the placement sequence, the additional sources of positional inaccuracy are eliminated. Overhead gantry-style machine has the best placement accuracy among all types and is utilized by flexible placers exclusively. It offers greater flexibility and accuracy, but cannot match the speeds of other styles. Machines with multiple gantries can achieve faster speed.\nStationary turret/fixed turret.\nStationary turret system has a relatively higher speed due to a series of identical heads rotating on a single turret. The feeder moves in the X direction to a fixed pickup location. As many as 36 vacuum nozzles around the perimeter of the rotating turret provide Z and theta alignment. Turret rotates multiple heads between pickup and placement locations. The PCB moves in X and Y direction under the rotating heads, pausing beneath the correct placement location. Comparing to a gantry head, the simultaneous movements of feeders and PCBs greatly improve the average placement rate. Because passive components do not demand a great placement accuracy, it is exclusively applied in chip shooters. Stationary turret system has a limitation of requiring large footprint for the moving feeder bank (footprint =2*total feeder length). The possibility of dislodging components due to the moving board mechanism is another limitation.\nRevolver head.\nThis system combines the speed advantage of stationary turret and the footprint advantage of overhead gantry. It was first being used by Siemens. The stationary turret with multiple pickup heads performs simultaneous functions while moving components from pickup to placement locations. Multiple revolvers are mounted on independent gantries to pick multiple parts from stationary feeders before moving to the PWB. The moving turret and multiple turrets offer higher placement speed and make revolver head can be used in both chip shooters and flexible placers. But utilizing it in flexible placers had limited success in reality.\nSplit-axis.\nIn a split-axis system, the placement head moves in the X, theta and Z directions, while the PWB moves in the Y direction. As two moving components are involved, split-axis machine slightly more difficult to achieve high accuracy comparing to the overhead gantry machine. But it greatly improves placement speed.\nVacuum nozzle and grippers.\nVacuum nozzles are commonly used for handling all the components during the placement operations. There are a variety of vacuum nozzle sizes for different component sizes. For handling small components, positive pressure is often supplied in addition to vacuum at the moment of placement so that the component would be completely release from the nozzle.\nIn addition to vacuum nozzles, mechanical grippers could be required for handling of some odd-shaped parts. Self-centering mechanical grippers allow simultaneous pickup and automatic centering without the need for a vacuum. A pair of tweezers-type grippers would hold the part while centering it along one axis. However, there are some disadvantages with self-centering mechanical grippers: it is possible that the gripper edges could have contact with epoxy or solder paste. In addition, extra space is required between the components to accommodate the grippers.\nTypes of feeders.\nFeeders are used to feed components to the moveable pick-up mechanism of placement machines. Feeders move individual components to a fixed location and also assist the pickup head in removing components from their packaging. As the flexibility and placement rate of systems has increased, so have the demands made on the component feeder systems. A high product mix and correspondingly small batch sizes result in frequent feeder changing. Quick feeder changeover is required in order to minimize machine down-time, so feeders must be designed for fast replacement. Here are some of the common types of feeders.\nTape and reel feeders.\nTape and reel feeder is the most commonly used feeder design. Tape-on-reel feeders are loaded with a reel, which is placed onto a reel-reception. The peel-off carriage pulls the reel tape forward until the next component is in the pick-up position. When the sensor indicates that the component is at the pickup position, a holder moves down and locks-down the tape.\nTape feeders are most suitable for placing large quantities of identical small components. Tape feeders come in a variety of sizes and can be used for Small-outline integrated circuits (SOICs) and plastic leaded chip carriers (PLCCs).\nThe main disadvantage of the tape format is the inability to recycle the empty tapes. Especially in the case of small chip devices, the tape waste material weighs several times more than the packaged components. Moreover, there is additional cost for placing small inexpensive components in tape.\nStick feeders.\nStick feeders are designed for components packed in linear sticks (small ICs issued in low volumes). Components are moved to the pick-up location by gravity or vibration. It feeds any ordinary SOP, SOT and PLCC which are packaged in stick form. Due to the various possibilities of adjusting the size of the lane, the feeder can easily be adapted to many different component types.\nMatrix tray feeders.\nMatrix tray feeders are used for large, delicate or expensive components. They are developed out of the necessity for handling quad flat packs and fine pitch components. These hold the components securely without damaging the fragile leads. An entire matrix-profiled tray of components are moved to bring rows or individual components to pick-up location. This process is often slower compared to tape feeders as the components fed in matrix trays often require higher level of placement accuracy.\nBulk feeders.\nBulk feeders can handle chip style components that are used in large numbers. A bulk feeder usually dispenses components, which are stored in a bulk case, using a unique rotary positioning mechanism to position and orient components and feed them to the pick-up position using a stainless steel belt. They are cheaper compared with tape feeders as there are no tape packing, but traditionally the performance of bulk feeders is problematic because of construction and debris created during the feeding process.\nDirect die feeder.\nThe direct die feeders are mostly used for flip-chip or chip-on board. Direct die feeder could eliminate separate and dedicated production lines for SMT, bare die, and flip chip by combining them into one. It could also enabling total assembly solutions with much higher speed and flexibility, resulting in lower cost per placement. In addition, it could eliminate costly processes such as intermediate die transfer into pocketed tape, surf-tape, or waffle packs prior to placement.\nPlacement speed.\nThe placement speed is influenced by many factors in the placement process.\nFeeder breakdown.\nThe placement speed is affected by the line downtime. Since feeder problems are the a major source of downtime, the repair and maintenance of feeders are crucial for the component placement operations. Here are the common ways to detect feeder problems:\nPlacement system set up.\nAll on-line setup reduces the capacity and improper setup procedures could also create additional line downtime. No boards could be produced if the placement system is not set up. Due to the complexity of the feeder set up and changeover process, it is important for operators to be aware of the variety types of feeder mechanisms. There are additional tools that could be implemented to assist the placement set up, such as roll-up feeder carts, just-in-time (JIT) methods and smart feeders.\nPlacement speed derating.\nIn practice it is not possible to obtain the quoted theoretical maximum throughput rate for machines in a placement system. It is necessary to derate the theoretical numbers to obtain realistic values, due to unexpected downtime, board load and unload time and machine configuration. Other factors include PWB size, component mix, and the requirement for more complex vision recognition for fine-pitch components. There are many techniques of derating. Global derating considers system-wide stops, slow-downs and set ups as well as machine factors. To calculate the amount of global or system derating, one should take the average of the number of total components placed per hour in a long period (i.e. an entire product shift). Regularly scheduled stops should be included when determining the level of global derating the system requires. Rigorous derating, which considers each piece of equipment in service for a particular product individually, must be conducted by specific machine model for the line balancing. Rigorous derating values are necessary for full optimization of the process.", "Engineering,_Manufacturing": 0.9998797178, "qwen": "Yes"}
{"id": "27688852", "revid": "1141140647", "url": "https://en.wikipedia.org/wiki?curid=27688852", "title": "Process layout", "text": "In manufacturing engineering, process layout is a design for the floor plan of a plant which aims to improve efficiency by arranging equipment according to its function. The production line should ideally be designed to eliminate waste in material flows, inventory handling and management. \nIn process layout, the work stations and machinery are not arranged according to a particular production sequence. Instead, there is an assembly of similar operations or similar machinery in each department (for example, a drill department, a paint department, etc.)\nIt is also known as function layout. In this layout machining operation are performed in group together and not arranged according to any sequence. \nCriticism.\nA common criticism of this layout is that the work can be monotonous for staff, especially if they are involved only in one stage of the process.\nThis criticism can however be eliminated if the staff are rotated to different departments (involving different processes) thus developing a multi-skilled body of staff.", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "38008960", "revid": "5753110", "url": "https://en.wikipedia.org/wiki?curid=38008960", "title": "Compliant bonding", "text": "Compliant bonding is used to connect gold wires to electrical components such as integrated circuit \"chips\". It was invented by Alexander Coucoulas in the 1960s. The bond is formed well below the melting point of the mating gold surfaces and is therefore referred to as a solid-state type bond. The compliant bond is formed by transmitting heat and pressure to the bond region through a relatively thick indentable or \"compliant medium\", generally an aluminum tape (Figure 1).\nComparison with other solid state bond methods.\nSolid-state or pressure bonds form permanent bonds between a gold wire and a gold metal surface by bringing their mating surfaces in intimate contact at about 300 °C which is well below their respective melting points of 1064 °C, hence the term solid-state bonds.\nTwo commonly used methods of forming this type of bond are thermocompression bonding and thermosonic bonding. Both of these processes form the bonds with a hard faced bonding tool that makes direct contact to deform the gold wires against the gold mating surfaces (Figure 2).\nSince gold is the only metal that does not form an oxide coating which can interfere with making a reliable metal to metal contact, gold wires are widely used to make these important wire connections in the field of microelectronic packaging. During the compliant bonding cycle the bond pressure is uniquely\ncontrolled by the inherent flow properties of the aluminum compliant tape (Figure 3). Therefore, if higher bond pressures are needed to increase the final deformation (flatness) of a compliant bonded gold wire, a higher yielding alloy of aluminum could be employed. The use of a compliant medium also overcomes the thickness variations when attempting to bond a multiple number of conductor wires simultaneously to a gold metalized substrate (Figure 4). It also prevents the leads from being excessively deformed since the compliant member deforms around the leads during the bonding cycle thus eliminating mechanical failure of a bonded wire due to excessive deformation from a hard faced tool (Figure 3) which is employed by thermocompression, and thermosonic bonding.\nHistory.\nAn important application for compliant bonding arose in the early 1960s, when techniques were developed for fabricating a beam leaded silicon integrated circuit “chip” consisting of pre-attached electroformed 0.005-inch thick gold leads or “beams” extending from the silicon chip (Figure 5). Thus the beam leaded “chip” eliminated the need to thermosonically bond wires directly onto metallized pads of the fragile silicon chip (as shown in Figure 6) The extended ends of the electroformed beams could then be permanently solid-state bonded to a matching metallized sunburst circuit which has been pre-deposited on a ceramic substrate appropriately packaged in a computer in the making. Figure 7. shows a preshaped hard faced tool thermocompression bonding all of the beam leads of a chip in one bonding cycle. In order to avoid excessively deforming the fine beam leads with the hard bonding tool and putting them at risk of mechanical failure, the applied bonding forces have to be carefully monitored.\nThe invention of compliant bonding eliminated the problems associated with a hard faced bonding tool and therefore was ideally suited to simultaneously bond all of the extended electroplated gold beam leads to a matching gold metallized sunburst patterned ceramic substrate packaged in a computer (Figure 8). For example, compliant bonding eliminated the problems of using a hard faced bonding tool such as: attempting to uniformly deform the nominally 0.005-inch thick beams leads having slight variations in their thickness; excessive lead deformation that could cause mechanical damage and an ultimate \"costly\" failure of these fine beam leaded silicon chips which are the \"brains\" of our computers. The compliant bonding tape media offered the additional advantage of carrying the \"beam leaded silicon chip\" to the bonding site thus facilitating production. \nFigures 9. and 10 show that the compliant tape offers the advantage of carrying the beam leaded chip to the bonding site as discussed above. Figure 11 shows a beam leaded silicon integrated circuit compliantly bonded to a gold metallized sunburst pattern deposited on an alumina ceramic substrate which will be encapsulated and packaged in a computer-type device. Figure 12 shows the spent compliant member used to bond the chip in Figure 11 which clearly shows a mirror image of the uniformly bonded beam leads.\nSilicon integrated circuit.\nThe two forms of integrated circuits discussed above were the beam leaded integrated circuit composed of attached electroformed gold leads or beams (Figure 5) and the silicon integrated circuit chip (Figure 6). With respect to the beam leaded silicon chip, both compliant and thermocompression bonding can be employed since each have their advantages. At this time, the most widely used form is the silicon integrated circuit chip, without the beam leads, which therefore requires electrical connections directly to the metallized silicon Chip (Figure 6). If wire connections is the method of choice to form these connections, thermosonic bonding gold wires directly to the silicon chip has been the process most widely used because of its proven reliability as a result of the low bonding parameters of force, temperature, and time needed to form the bond.", "Engineering,_Manufacturing": 0.9998879433, "qwen": "Yes"}
{"id": "43912217", "revid": "3606755", "url": "https://en.wikipedia.org/wiki?curid=43912217", "title": "Strati (automobile)", "text": "Strati is an electric car developed by Local Motors and manufactured in collaboration with Cincinnati Incorporated and Oak Ridge National Laboratory. It is the world's first electric car to heavily utilize 3D printing during the production process. The car was manufactured using a Large Scale 3D Printer developed by ORNL and Cincinnati Inc. The car took just 44 hours to print during the 2014 International Manufacturing Technology Show in Chicago, Illinois. The printing was followed by three days of milling and assembling, with the completed car first test-driven on September 13, 2014. Strati is claimed to be the world's first 3D-Printed electric car.\nDesign.\nIn April 2014, Local Motors organized the 3D Printed Car Design Challenge crowdsourcing to assist in the production of a full-body 3D-printed car. Seven finalists were selected from more than 200 submissions. In June 2014, Local Motors announced that the challenge was won by Michele Anoé of Italy, who was awarded the $5,000 prize. After the contest, Local Motors took the design and made several modifications so that the car could be manufactured through 3D-Printing.\nSpecifications.\nThe two-seat Strati is considered to be a \"neighborhood\" electric car. Depending on the configuration of the battery packs, the range of the car can be with top speeds of . The car is not designed to be used on highways, as it does not meet the required safety test requirements. Production is planned by the end of 2015, with prices between $18,000 and $30,000.\nManufacturing.\nFollowing the design competition, Local Motors handed off the design to the engineers at ORNL who perfected the process of Large Scale 3D Printing such that the Local Motors design could actually be manufactured. ORNL worked with Cincinnati Incorporated to develop the printer that would allow for the printing of the entire car. With the printer, ORNL and Cincinnati Inc. manufactured all body parts of the car and allowed for easy mounting of the mechanical parts, such as the electric motors and batteries.\nStrati is printed from thermoplastic using a big area additive manufacturing (BAAM) machine (a large FDM 3D-printer). This material is fully recyclable, which can be chopped and reprocessed to be used in printing another car. After the car is printed, the mechanical and electrical parts such as battery, motors, and suspension are manually assembled.\nThe printing process has been improved by ORNL since July 2014, bringing the printing time of 140 hours down to less than 45 hours in September. Since IMTS, ORNL has brought the printing time of the Strati to less than 24 hours and is continuing their research efforts with the hope of printing the car in less than 10 hours.\nThe world's first title.\nDisputes exist over the title of the world's first 3D-printed car. In 2010, a hybrid car \"Urbee\" was 3D-printed using an additive manufacturing process for the entire body. Local Motors claimed that Urbee's manufacturer only 3D-printed the panels and other exterior parts, but used standard parts for the internal structure. For Strati, the company claimed that 3D printing was used for all except the parts that are \"mechanically involved\". Strati claims to be the world's first 3D-printed electric car.", "Engineering,_Manufacturing": 0.9999252558, "qwen": "Yes"}
{"id": "54809981", "revid": "7852030", "url": "https://en.wikipedia.org/wiki?curid=54809981", "title": "Choc Nut", "text": "Choc Nut (stylized as Choc⋆Nut) is a trademark for a candy bar manufactured by Annie's Sweets Manufacturing and Packaging Corporation, a Philippine-based company. The ingredients of Choc Nut include peanuts, sugar, milk powder, cocoa powder and vanilla.Asian supermarkets and Filipino stores overseas sell the candy. Many restaurants and cafes in the Philippines use Choc Nut as a popular ingredient in confections, drinks, and even cocktails.\nHistory.\nChoc Nut was originally manufactured by New Unity Sweets Manufacturing Corporation (Unisman) in Malabon. In 2013, the brand came under the ownership of Annie's Manufacturing and Packaging Corporation, the company that produces Choc Nut's rival brand, Hany.\nIn 2018, Choc Nut extended its product line to include a sweetened chocolate peanut spread.\nPackaging.\nChoc Nut comes in 24-piece \"King\" or 16-piece \"SP\" packages. The 24-piece \"King\" package consists of twenty-four 8-gram bars, while the 16-piece \"SP\" package consists of sixteen 16-gram bars. Each bar is individually-wrapped in paper-backed foil and an outer packaging film (white paper during the Unisman era) bearing the brand's logo and signature red stripes. The packages are a bronze colour with white and red lines running through it horizontally.\nIn popular culture.\nIn recognition of its status as a pop culture icon, Choc Nut was given a prominent role in the graphic novel series \"Trese\" by Budjette Tan and Kajo Baldisimo. The references were also picked up in the animated series.", "Engineering,_Manufacturing": 0.699932754, "qwen": "Yes"}
{"id": "13111304", "revid": "1154162123", "url": "https://en.wikipedia.org/wiki?curid=13111304", "title": "Supply & Demand Chain Executive", "text": "\"Supply & Demand Chain Executive\" is the only publication covering the entire global supply chain, focusing on trucking, warehousing, packaging, procurement, risk management, professional development and more. Supply & Demand Chain Executive is a digital-only publication, and reaches over 109,000 industry subscribers via its twice-weekly e-newsletter, reaching executives in corporate procurement, purchasing, logistics and operations management in manufacturing and non-manufacturing industries.\nOverview.\nThis digital-only brand reaches executives in corporate procurement, purchasing, logistics and operations management in manufacturing and non-manufacturing industries. These are the supply chain technology leaders who select solutions and service providers to enhance efficiency within their specific sector. Go to https://www.supplychainnetworkmediakit.com/ for more information.\nInteractive Opportunities.\n\"Supply & Demand Chain Executive\" is the only publication covering the entire global supply chain, focusing on trucking, warehousing, packaging, procurement, risk management, professional development and more. Supply & Demand Chain Executive is a digital-only publication, and reaches over 109,000 industry subscribers via its twice-weekly e-newsletter, reaching executives in corporate procurement, purchasing, logistics and operations management in manufacturing and non-manufacturing industries. SDCExec.com is home to thought leadership pieces from supply chain industry experts, as well as SCN Summit, the Women in Supply Chain Forum, several awards and the Global Supply Chain Insights e-newsletter. Go to https://acbusiness.dragonforms.com/loading.do?omedasite=SDCEprefs&pk=managepref to subscribe.\nIn-Person Events.\n\"Supply & Demand Chain Executive\" owns and operates the Women in Supply Chain Forum, the industry’s premier networking and educational forum tailored to men and women in executive-level positions to expand their professional network and enhance their businesses through thought-provoking discussion panels. Go to https://www.womeninsupplychainforum.com/ for more information.\nVirtual Events.\n\"Supply & Demand Chain Executive\" owns and operates the SCN Summit, the premier virtual event aimed at educating logistics professionals on critical issues impacting the supply chain industry. Go to https://www.scnsummit.com/ for more information.", "Engineering,_Manufacturing": 0.9999171495, "qwen": "Yes"}
{"id": "13135449", "revid": "5846", "url": "https://en.wikipedia.org/wiki?curid=13135449", "title": "Hong Kong Electronics Fair", "text": "Hong Kong Electronics Fair (Autumn Edition) is organised by the Hong Kong Trade Development Council (HKTDC) and to be held at the Hong Kong Convention and Exhibition Centre in October every year. One of the fair's highlights is the Hall of Fame – a special section dedicated to high-quality electronic products that are distinguished by their design and function. The fair is organised into key thematic zones ranging from audio-visual products to navigation systems, and from home appliances to telecommunications products. At Technology Exchange Zone, Hong Kong's leading research facilities and companies display their latest technology ideas. In addition, a number of testing, inspection & certification services companies will exhibit at the fair, presenting an array of related services for the electronics industry.", "Engineering,_Manufacturing": 0.9989836216, "qwen": "Yes"}
{"id": "871165", "revid": "5846", "url": "https://en.wikipedia.org/wiki?curid=871165", "title": "Reflow oven", "text": "A reflow oven is a machine used primarily for reflow soldering of surface mount electronic components to printed circuit boards (PCBs). \nIn commercial high-volume use, reflow ovens take the form of a long tunnel containing a conveyor belt along which PCBs travel. For prototyping or hobbyist use PCBs can be placed in a small oven with a door.\nCommercial conveyorised reflow ovens contain multiple individually heated zones, which can be individually controlled for temperature. PCBs being processed travel through the oven and through each zone at a controlled rate. Technicians adjust the conveyor speed and zone temperatures to achieve a known time and temperature profile. The profile in use may vary depending on the requirements of the PCBs being processed at the time.\nTypes of reflow ovens.\nInfrared and convection ovens.\nIn infrared reflow ovens, the heat source is normally ceramic infrared heaters above and below the conveyor, which transfer heat to the PCBs by means of radiation. \nConvection ovens heat air in chambers, using that air to transfer heat to the PCBs by means of convection and conduction. They may be fan assisted to control the airflow within the oven. This indirect heating using air allows more accurate temperature control than directly heating PCBs by infrared radiation, as PCBs and components vary in infrared absorptance.\nOvens may use a combination of infrared radiative heating and convection heating, and would then be known as 'infrared convection' ovens.\nSome ovens are designed to reflow PCBs in an oxygen-free atmosphere. Nitrogen (N2) is a common gas used for this purpose. This minimizes oxidation of the surfaces to be soldered. The nitrogen reflow oven takes a few minutes to reduce Oxygen concentration to acceptable levels within the chamber. Thus nitrogen ovens typically have nitrogen injection in at all times which decreases defect rates.\nVapour phase oven.\nThe heating of the PCBs is sourced by thermal energy emitted by the phase transition of a heat transfer liquid (e. g. PFPE) condensing on the PCBs. The liquid used is chosen with a desired boiling point in mind to suit the solder alloy to be reflowed.\nSome advantages of vapour phase soldering are:\nThis is also known as condensation soldering.\nThermal profiling.\nThermal profiling is the act of measuring several points on a circuit board to determine the thermal excursion it takes through the soldering process.\nIn the electronics manufacturing industry, SPC (statistical process control) helps determine if the process is in control, measured against the reflow parameters defined by the soldering technologies and component requirements. ", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "50232146", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=50232146", "title": "Thermal cleaning", "text": "Thermal cleaning is a combined process involving pyrolysis and oxidation. As an industrial application, thermal cleaning is used to remove organic substances such as polymers, plastics and coatings from parts, products or production components like extruder screws, spinnerets and static mixers. Thermal cleaning is the most common cleaning method in industrial environment. A variety of different methods have been developed so far for a wide range of applications.\nProcess.\nHeat is supplied for pyrolysis and air is supplied for oxidation. Depending on the procedure, pyrolysis and oxidation can be applied consecutively or simultaneously. During thermal cleaning, organic material is converted into volatile organic compounds, hydrocarbons and carbonized gas. Inorganic elements remain. Typical process temperatures range between 400 °C to 540 °C (750 °F to 1000 °F).\nSeveral types of industrial thermal cleaning systems are available:\nFluidized bed systems.\nFluidized bed systems use sand or aluminium oxide (alumina) as heating medium. They apply pyrolysis and oxidation simultaneously. These systems clean fast, from 30 minutes process time up to two hours. The medium does not melt or boil, nor emit any vapors or odors. Thermal shock can be a problem with some parts. Pollution control devices may be needed to protect the environment.\nVacuum ovens.\nVacuum ovens use pyrolysis in a vacuum. This method is very safe because uncontrolled combustion inside the cleaning chamber is avoided. The cleaning process in this relatively new approach takes 8 to 30 hours. Vacuum pyrolysis is the only method that applies pyrolysis and oxidation consecutively. In two-chamber versions, molten plastic drains into an unheated chamber to capture the bulk of the polymer to reduce the fumes. Vacuum ovens are also electrically powered.\nBurn-off ovens.\nBurn-off ovens, also known as heat-cleaning ovens, are gas-fired and used for removing organics from heavy and large metal parts. The process time is moderate, approximately 4 hours. Fires can occur from the fumes created during cleaning. The design is simple and inexpensive. Different types are available. Modern types contain an additional afterburner that operates at a minimum of 1,500°F (816°C) and consumes any smoke created by the process.\nMolten salt baths.\nMolten salt baths belong to the oldest thermal cleaning systems. Cleaning with molten salt is fast: 15 to 30 minutes process time. The process has the risk of dangerous splatters due to chemical reactivity, or other potential hazards, like explosions or toxic hydrogen cyanide gas. Another disadvantage is that parts can be warped or altered in design tolerances. Molten salt baths can be environmentally unfriendly. Due to their disadvantages, they are rarely used today.", "Engineering,_Manufacturing": 0.9999688864, "qwen": "Yes"}
{"id": "50233125", "revid": "3784107", "url": "https://en.wikipedia.org/wiki?curid=50233125", "title": "Dneprospetsstal", "text": "Dneprospetsstal , known as DSS, is a Ukrainian manufacturer of special stainless steel. The company is based in Zaporizhia in southeastern Ukraine, and was founded as a state-run enterprise in . Its full name is JPrSC Electrometallurgical Works Dneprospetsstal named after A. N. Kuzmin. It is a publicly traded company.\nDneprospetsstal manufactures and sells metal products of stainless, tool, high-speed (including those produced by the PM-method), bearing, structural, alloyed and carbon steel grades. Dneprospetsstal manufactures over 800 steel grades of 1200 section sizes. \nDSS' products are used in the manufacture of machinery parts, tools for metal and alloy machining, seamless pipes and bearings. \nCompany’s steel production capacities comprise steel-making shops equipped with open basic electric arc furnaces, induction furnace and electro slag re-melting (ESR) and vacuum arc re-melting (VAR) facilities.\nDSS steel processing is concentrated in a rolling shop, which contains blooming mills and a few rolling mills, a forging shop, a forging press shop, a cold drawing shop and a metal finishing shop.\nDSS quality management system meets the requirements of international standards. In 2008, the enterprise was certified to ISO 9001:2008. Product quality meets the requirements of GOST (CIS), ASTM, AISI (USA), EN (EU), DIN (Germany), BS (Great Britain), AFNOR (France), JIS (Japan).", "Engineering,_Manufacturing": 0.9999822378, "qwen": "Yes"}
{"id": "325831", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=325831", "title": "Injection moulding", "text": "Injection moulding (U.S. spelling: injection molding) is a manufacturing process for producing parts by injecting molten material into a mould, or mold. Injection moulding can be performed with a host of materials mainly including metals (for which the process is called die-casting), glasses, elastomers, confections, and most commonly thermoplastic and thermosetting polymers. Material for the part is fed into a heated barrel, mixed (using a helical screw), and injected into a mould cavity, where it cools and hardens to the configuration of the cavity. After a product is designed, usually by an industrial designer or an engineer, moulds are made by a mould-maker (or toolmaker) from metal, usually either steel or aluminium, and precision-machined to form the features of the desired part. Injection moulding is widely used for manufacturing a variety of parts, from the smallest components to entire body panels of cars. Advances in 3D printing technology, using photopolymers that do not melt during the injection moulding of some lower-temperature thermoplastics, can be used for some simple injection moulds.\nInjection moulding uses a special-purpose machine that has three parts: the injection unit, the mould and the clamp. Parts to be injection-moulded must be very carefully designed to facilitate the moulding process; the material used for the part, the desired shape and features of the part, the material of the mould, and the properties of the moulding machine must all be taken into account. The versatility of injection moulding is facilitated by this breadth of design considerations and possibilities.\nApplications.\nInjection moulding is used to create many things such as wire spools, packaging, bottle caps, automotive parts and components, toys, pocket combs, some musical instruments (and parts of them), one-piece chairs and small tables, storage containers, mechanical parts (including gears), and most other plastic products available today. Injection moulding is the most common modern method of manufacturing plastic parts; it is ideal for producing high volumes of the same object.\nProcess characteristics.\nInjection moulding uses a ram or screw-type plunger to force molten plastic or rubber material into a mould cavity; this solidifies into a shape that has conformed to the contour of the mould. It is most commonly used to process both thermoplastic and thermosetting polymers, with the volume used of the former being considerably higher. Thermoplastics are prevalent due to characteristics that make them highly suitable for injection moulding, such as ease of recycling, versatility for a wide variety of applications, and ability to soften and flow on heating. Thermoplastics also have an element of safety over thermosets; if a thermosetting polymer is not ejected from the injection barrel in a timely manner, chemical crosslinking may occur causing the screw and check valves to seize and potentially damaging the injection moulding machine.\nInjection moulding consists of the high pressure injection of the raw material into a mould, which shapes the polymer into the desired form. Moulds can be of a single cavity or multiple cavities. In multiple cavity moulds, each cavity can be identical and form the same parts or can be unique and form multiple different geometries during a single cycle. Moulds are generally made from tool steels, but stainless steels and aluminium moulds are suitable for certain applications. Aluminium moulds are typically ill-suited for high volume production or parts with narrow dimensional tolerances, as they have inferior mechanical properties and are more prone to wear, damage, and deformation during the injection and clamping cycles; however, aluminium moulds are cost-effective in low-volume applications, as mould fabrication costs and time are considerably reduced. Many steel moulds are designed to process well over a million parts during their lifetime and can cost hundreds of thousands of dollars to fabricate.\nWhen thermoplastics are moulded, typically pelletised raw material is fed through a hopper into a heated barrel with a reciprocating screw. Upon entrance to the barrel, the temperature increases and the Van der Waals forces that resist relative flow of individual chains are weakened as a result of increased space between molecules at higher thermal energy states. This process reduces its viscosity, which enables the polymer to flow with the driving force of the injection unit. The screw delivers the raw material forward, mixes and homogenises the thermal and viscous distributions of the polymer, and reduces the required heating time by mechanically shearing the material and adding a significant amount of frictional heating to the polymer. The material feeds forward through a check valve and collects at the front of the screw into a volume known as a shot. A shot is the volume of material that is used to fill the mould cavity, compensate for shrinkage, and provide a cushion (approximately 10% of the total shot volume, which remains in the barrel and prevents the screw from bottoming out) to transfer pressure from the screw to the mould cavity. When enough material has gathered, the material is forced at high pressure and velocity into the part forming cavity. The exact amount of shrinkage is a function of the resin being used, and can be relatively predictable. To prevent spikes in pressure, the process normally uses a transfer position corresponding to a 95–98% full cavity where the screw shifts from a constant velocity to a constant pressure control. Often injection times are well under 1 second. Once the screw reaches the transfer position the packing pressure is applied, which completes mould filling and compensates for thermal shrinkage, which is quite high for thermoplastics relative to many other materials. The packing pressure is applied until the gate (cavity entrance) solidifies. Due to its small size, the gate is normally the first place to solidify through its entire thickness. Once the gate solidifies, no more material can enter the cavity; accordingly, the screw reciprocates and acquires material for the next cycle while the material within the mould cools so that it can be ejected and be dimensionally stable. This cooling duration is dramatically reduced by the use of cooling lines circulating water or oil from an external temperature controller. Once the required temperature has been achieved, the mould opens and an array of pins, sleeves, strippers, etc. are driven forward to demould the article. Then, the mould closes and the process is repeated.\nFor a two-shot mould, two separate materials are incorporated into one part. This type of injection moulding is used to add a soft touch to knobs, to give a product multiple colours, or to produce a part with multiple performance characteristics.\nFor thermosets, typically two different chemical components are injected into the barrel. These components immediately begin irreversible chemical reactions that eventually crosslinks the material into a single connected network of molecules. As the chemical reaction occurs, the two fluid components permanently transform into a viscoelastic solid. Solidification in the injection barrel and screw can be problematic and have financial repercussions; therefore, minimising the thermoset curing within the barrel is vital. This typically means that the residence time and temperature of the chemical precursors are minimised in the injection unit. The residence time can be reduced by minimising the barrel's volume capacity and by maximising the cycle times. These factors have led to the use of a thermally isolated, cold injection unit that injects the reacting chemicals into a thermally isolated hot mould, which increases the rate of chemical reactions and results in shorter time required to achieve a solidified thermoset component. After the part has solidified, valves close to isolate the injection system and chemical precursors, and the mould opens to eject the moulded parts. Then, the mould closes and the process repeats.\nPre-moulded or machined components can be inserted into the cavity while the mould is open, allowing the material injected in the next cycle to form and solidify around them. This process is known as Insert moulding and allows single parts to contain multiple materials. This process is often used to create plastic parts with protruding metal screws so they can be fastened and unfastened repeatedly. This technique can also be used for In-mould labelling and film lids may also be attached to moulded plastic containers.\nA parting line, sprue, gate marks, and ejector pin marks are usually present on the final part. None of these features are typically desired, but are unavoidable due to the nature of the process. Gate marks occur at the gate that joins the melt-delivery channels (sprue and runner) to the part forming cavity. Parting line and ejector pin marks result from minute misalignments, wear, gaseous vents, clearances for adjacent parts in relative motion, and/or dimensional differences of the melting surfaces contacting the injected polymer. Dimensional differences can be attributed to non-uniform, pressure-induced deformation during injection, machining tolerances, and non-uniform thermal expansion and contraction of mould components, which experience rapid cycling during the injection, packing, cooling, and ejection phases of the process. Mould components are often designed with materials of various coefficients of thermal expansion. These factors cannot be simultaneously accounted for without astronomical increases in the cost of design, fabrication, processing, and quality monitoring. The skillful mould and part designer positions these aesthetic detriments in hidden areas if feasible.\nHistory.\nIn 1846 the British inventor Charles Hancock, a relative of Thomas Hancock, patented an injection molding machine.\nAmerican inventor John Wesley Hyatt, together with his brother Isaiah, patented one of the first injection moulding machines in 1872. This machine was relatively simple compared to machines in use today: it worked like a large hypodermic needle, using a plunger to inject plastic through a heated cylinder into a mould. The industry progressed slowly over the years, producing products such as collar stays, buttons, and hair combs(generally though, plastics, in its modern definition, are a more recent development ).\nThe German chemists Arthur Eichengrün and Theodore Becker invented the first soluble forms of cellulose acetate in 1903, which was much less flammable than cellulose nitrate. It was eventually made available in a powder form from which it was readily injection moulded. Arthur Eichengrün developed the first injection moulding press in 1919. In 1939, Arthur Eichengrün patented the injection moulding of plasticised cellulose acetate.\nThe industry expanded rapidly in the 1940s because World War II created a huge demand for inexpensive, mass-produced products. In 1946, American inventor James Watson Hendry built the first screw injection machine, which allowed much more precise control over the speed of injection and the quality of articles produced. This machine also allowed material to be mixed before injection, so that coloured or recycled plastic could be added to virgin material and mixed thoroughly before being injected. In the 1970s, Hendry went on to develop the first gas-assisted injection moulding process, which permitted the production of complex, hollow articles that cooled quickly. This greatly improved design flexibility as well as the strength and finish of manufactured parts while reducing production time, cost, weight and waste. By 1979, plastic production overtook steel production, and by 1990, aluminium moulds were widely used in injection moulding. Today, screw injection machines account for the vast majority of all injection machines.\nThe plastic injection moulding industry has evolved over the years from producing combs and buttons to producing a vast array of products for many industries including automotive, medical, aerospace, consumer products, toys, plumbing, packaging, and construction.\nExamples of polymers best suited for the process.\nMost polymers, sometimes referred to as resins, may be used, including all thermoplastics, some thermosets, and some elastomers. Since 1995, the total number of available materials for injection moulding has increased at a rate of 750 per year; there were approximately 18,000 materials available when that trend began. Available materials include alloys or blends of previously developed materials, so product designers can choose the material with the best set of properties from a vast selection. Major criteria for selection of a material are the strength and function required for the final part, as well as the cost, but also each material has different parameters for moulding that must be taken into account. Other considerations when choosing an injection moulding material include flexural modulus of elasticity, or the degree to which a material can be bent without damage, as well as heat deflection and water absorption. Common polymers like epoxy and phenolic are examples of thermosetting plastics while nylon, polyethylene, and polystyrene are thermoplastic. Until comparatively recently, plastic springs were not possible, but advances in polymer properties make them now quite practical. Applications include buckles for anchoring and disconnecting outdoor-equipment webbing.\nEquipment.\nInjection moulding machines consist of a material hopper, an injection ram or screw-type plunger, and a heating unit. Also known as platens, they hold the moulds in which the components are shaped. Presses are rated by tonnage, which expresses the amount of clamping force that the machine can exert. This force keeps the mould closed during the injection process. Tonnage can vary from less than 5 tons to over 9,000 tons, with the higher figures used in comparatively few manufacturing operations. The total clamp force needed is determined by the projected area of the part being moulded. This projected area is multiplied by a clamp force of from 1.8 to 7.2 tons for each square centimetre of the projected areas. As a rule of thumb, 4 or 5 tons/in2 can be used for most products. If the plastic material is very stiff, it requires more injection pressure to fill the mould, and thus more clamp tonnage to hold the mould closed. The required force can also be determined by the material used and the size of the part. Larger parts require higher clamping force.\nMould.\nMould or die are the common terms used to describe the tool used to produce plastic parts in moulding.\nSince moulds have been expensive to manufacture, they were usually only used in mass production where thousands of parts were being produced. Typical moulds are constructed from hardened steel, pre-hardened steel, aluminium, and/or beryllium-copper alloy. The choice of material to build a mould from is primarily one of economics; in general, steel moulds cost more to construct, but their longer lifespan offsets the higher initial cost over a higher number of parts made before wearing out. Pre-hardened steel moulds are less wear-resistant and are used for lower volume requirements or larger components; their typical steel hardness is 38–45 on the Rockwell-C scale. Hardened steel moulds are heat treated after machining; these are by far superior in terms of wear resistance and lifespan. Typical hardness ranges between 50 and 60 Rockwell-C (HRC). Aluminium moulds can cost substantially less, and when designed and machined with modern computerised equipment can be economical for moulding tens or even hundreds of thousands of parts. Beryllium copper is used in areas of the mould that require fast heat removal or areas that see the most shear heat generated. The moulds can be manufactured either by CNC machining or by using electrical discharge machining processes.\nMould design.\nThe mould consists of two primary components, the injection mould (A plate) and the ejector mould (B plate). These components are also referred to as \"moulder\" and \"mouldmaker\". Plastic resin enters the mould through a \"sprue\" or \"gate\" in the injection mould; the sprue bushing is to seal tightly against the nozzle of the injection barrel of the moulding machine and to allow molten plastic to flow from the barrel into the mould, also known as the cavity. The sprue bushing directs the molten plastic to the cavity images through channels that are machined into the faces of the A and B plates. These channels allow plastic to run along them, so they are referred to as runners. The molten plastic flows through the runner and enters one or more specialised gates and into the cavity geometry to form the desired part.\nThe amount of resin required to fill the sprue, runner and cavities of a mould comprises a \"shot\". Trapped air in the mould can escape through air vents that are ground into the parting line of the mould, or around ejector pins and slides that are slightly smaller than the holes retaining them. If the trapped air is not allowed to escape, it is compressed by the pressure of the incoming material and squeezed into the corners of the cavity, where it prevents filling and can also cause other defects. The air can even become so compressed that it ignites and burns the surrounding plastic material.\nTo allow for removal of the moulded part from the mould, the mould features must not overhang one another in the direction that the mould opens, unless parts of the mould are designed to move from between such overhangs when the mould opens using components called Lifters.\nSides of the part that appear parallel with the direction of draw (the axis of the cored position (hole) or insert is parallel to the up and down movement of the mould as it opens and closes) are typically angled slightly, called draft, to ease release of the part from the mould. Insufficient draft can cause deformation or damage. The draft required for mould release is primarily dependent on the depth of the cavity; the deeper the cavity, the more draft necessary. Shrinkage must also be taken into account when determining the draft required. If the skin is too thin, then the moulded part tends to shrink onto the cores that form while cooling and cling to those cores, or the part may warp, twist, blister or crack when the cavity is pulled away.\nA mould is usually designed so that the moulded part reliably remains on the ejector (B) side of the mould when it opens, and draws the runner and the sprue out of the (A) side along with the parts. The part then falls freely when ejected from the (B) side. Tunnel gates, also known as submarine or mould gates, are located below the parting line or mould surface. An opening is machined into the surface of the mould on the parting line. The moulded part is cut (by the mould) from the runner system on ejection from the mould. Ejector pins, also known as knockout pins, are circular pins placed in either half of the mould (usually the ejector half), which push the finished moulded product, or runner system out of a mould.The ejection of the article using pins, sleeves, strippers, etc., may cause undesirable impressions or distortion, so care must be taken when designing the mould.\nThe standard method of cooling is passing a coolant (usually water) through a series of holes drilled through the mould plates and connected by hoses to form a continuous pathway. The coolant absorbs heat from the mould (which has absorbed heat from the hot plastic) and keeps the mould at a proper temperature to solidify the plastic at the most efficient rate.\nTo ease maintenance and venting, cavities and cores are divided into pieces, called \"inserts\", and sub-assemblies, also called \"inserts\", \"blocks\", or \"chase blocks\". By substituting interchangeable inserts, one mould may make several variations of the same part.\nMore complex parts are formed using more complex moulds. These may have sections called slides, that move into a cavity perpendicular to the draw direction, to form overhanging part features. When the mould is opened, the slides are pulled away from the plastic part by using stationary “angle pins” on the stationary mould half. These pins enter a slot in the slides and cause the slides to move backward when the moving half of the mould opens. The part is then ejected and the mould closes. The closing action of the mould causes the slides to move forward along the angle pins.\nA mould can produce several copies of the same parts in a single \"shot\". The number of \"impressions\" in the mould of that part is often incorrectly referred to as cavitation. A tool with one impression is often called a single \"impression\" (cavity) mould. A mould with two or more cavities of the same parts is usually called a multiple \"impression\" (cavity) mould. (Not to be confused with \"Multi-\"shot\" moulding\" {which is dealt with in the next section.}) Some extremely high production volume moulds (like those for bottle caps) can have over 128 cavities.\nIn some cases, multiple cavity tooling moulds a series of different parts in the same tool. Some toolmakers call these moulds family moulds, as all the parts are related—e.g., plastic model kits.\nSome moulds allow previously moulded parts to be reinserted to allow a new plastic layer to form around the first part. This is often referred to as overmoulding. This system can allow for production of one-piece tires and wheels.\nMoulds for highly precise and extremely small parts from micro injection molding requires extra care in the design stage, as material resins react differently compared to their full-sized counterparts where they must quickly fill these incredibly small spaces, which puts them under intense shear strains. \nMulti-shot moulding.\nTwo-shot, double-shot or multi-shot moulds are designed to \"overmould\" within a single moulding cycle and must be processed on specialised injection moulding machines with two or more injection units. This process is actually an injection moulding process performed \"twice\" and therefore can allow only for a much smaller margin of error. In the first step, the base colour material is moulded into a basic shape, which contains spaces for the second shot. Then the second material, a different colour, is injection-moulded into those spaces. Pushbuttons and keys, for instance, made by this process have markings that cannot wear off, and remain legible with heavy use.\nMould storage.\nManufacturers go to great lengths to protect custom moulds due to their high average costs. The perfect temperature and humidity level is maintained to ensure the longest possible lifespan for each custom mould. Custom moulds, such as those used for rubber injection moulding, are stored in temperature and humidity controlled environments to prevent warping.\nTool materials.\nTool steel is often used. Mild steel, aluminium, nickel or epoxy are suitable only for prototype or very short production runs. Modern hard aluminium (7075 and 2024 alloys) with proper mould design, can easily make moulds capable of 100,000 or more part life with proper mould maintenance.\nMachining.\nMoulds are built through two main methods: standard machining and EDM. Standard machining, in its conventional form, has historically been the method of building injection moulds. With technological developments, CNC machining became the predominant means of making more complex moulds with more accurate mould details in less time than traditional methods.\nThe electrical discharge machining (EDM) or spark erosion process has become widely used in mould making. As well as allowing the formation of shapes that are difficult to machine, the process allows pre-hardened moulds to be shaped so that no heat treatment is required. Changes to a hardened mould by conventional drilling and milling normally require annealing to soften the mould, followed by heat treatment to harden it again. EDM is a simple process in which a shaped electrode, usually made of copper or graphite, is very slowly lowered onto the mould surface over a period of many hours, which is immersed in paraffin oil (kerosene). A voltage applied between tool and mould causes spark erosion of the mould surface in the inverse shape of the electrode.\nCost.\nThe number of cavities incorporated into a mould directly correlate in moulding costs. Fewer cavities require far less tooling work, so limiting the number of cavities lowers initial manufacturing costs to build an injection mould.\nAs the number of cavities play a vital role in moulding costs, so does the complexity of the part's design. Complexity can be incorporated into many factors such as surface finishing, tolerance requirements, internal or external threads, fine detailing or the number of undercuts that may be incorporated.\nFurther details, such as undercuts, or any feature that needs additional tooling, increases mould cost. Surface finish of the core and cavity of moulds further influences cost.\nRubber injection moulding process produces a high yield of durable products, making it the most efficient and cost-effective method of moulding. Consistent vulcanisation processes involving precise temperature control significantly reduces all waste material.\nInjection process.\nUsually, the plastic materials are formed in the shape of pellets or granules and sent from the raw material manufacturers in paper bags. With injection moulding, pre-dried granular plastic is fed by a forced ram from a hopper into a heated barrel. As the granules are slowly moved forward by a screw-type plunger, the plastic is forced into a heated chamber, where it is melted. As the plunger advances, the melted plastic is forced through a nozzle that rests against the mould, allowing it to enter the mould cavity through a gate and runner system. The mould remains cold so the plastic solidifies almost as soon as the mould is filled.\nInjection moulding cycle.\nThe sequence of the events during the injection mould of a plastic part is called the injection moulding cycle. The cycle begins when the mould closes, followed by the injection of the polymer into the mould cavity. Once the cavity is filled, a holding pressure is maintained to compensate for material shrinkage. In the next step, the screw turns, feeding the next shot to the front screw. This causes the screw to retract as the next shot is prepared. Once the part is sufficiently cool, the mould opens and the part is ejected.\nScientific versus traditional moulding.\nTraditionally, the injection portion of the moulding process was done at one constant pressure to fill and pack the cavity. This method, however, allowed for a large variation in dimensions from cycle-to-cycle. More commonly used now is scientific or decoupled moulding, a method pioneered by RJG Inc. In this the injection of the plastic is \"decoupled\" into stages to allow better control of part dimensions and more cycle-to-cycle (commonly called shot-to-shot in the industry) consistency. First the cavity is filled to approximately 98% full using velocity (speed) control. Although the pressure should be sufficient to allow for the desired speed, pressure limitations during this stage are undesirable. Once the cavity is 98% full, the machine switches from velocity control to pressure control, where the cavity is \"packed out\" at a constant pressure, where sufficient velocity to reach desired pressures is required. This lets workers control part dimensions to within thousandths of an inch or better.\nDifferent types of injection moulding processes.\nAlthough most injection moulding processes are covered by the conventional process description above, there are several important moulding variations including, but not limited to:\nA more comprehensive list of injection moulding processes may be found here: \nProcess troubleshooting.\nLike all industrial processes, injection molding can produce flawed parts, even in toys. In the field of injection moulding, troubleshooting is often performed by examining defective parts for specific defects and addressing these defects with the design of the mould or the characteristics of the process itself. Trials are often performed before full production runs in an effort to predict defects and determine the appropriate specifications to use in the injection process.\nWhen filling a new or unfamiliar mould for the first time, where shot size for that mould is unknown, a technician/tool setter may perform a trial run before a full production run. They start with a small shot weight and fills gradually until the mould is 95 to 99% full. Once they achieve this, they apply a small amount of holding pressure and increase holding time until gate freeze off (solidification time) has occurred. Gate freeze off time can be determined by increasing the hold time, and then weighing the part. When the weight of the part does not change, the gate has frozen and no more material is injected into the part. Gate solidification time is important, as this determines cycle time and the quality and consistency of the product, which itself is an important issue in the economics of the production process. Holding pressure is increased until the parts are free of sinks and part weight has been achieved.\nMoulding defects.\nInjection moulding is a complex technology with possible production problems. They can be caused either by defects in the moulds, or more often by the moulding process itself.\nMethods such as industrial CT scanning can help with finding these defects externally as well as internally.\nTolerances.\nTolerance depends on the dimensions of the part. An example of a standard tolerance for a 1-inch dimension of an LDPE part with 0.125 inch wall thickness is +/- 0.008 inch (0.2 mm).\nPower requirements.\nThe power required for this process of injection moulding depends on many things and varies between materials used. \"Manufacturing Processes Reference Guide\" states that the power requirements depend on \"a material's specific gravity, melting point, thermal conductivity, part size, and molding rate.\" Below is a table from page 243 of the same reference as previously mentioned that best illustrates the characteristics relevant to the power required for the most commonly used materials.\nRobotic moulding.\nAutomation means that the smaller size of parts permits a mobile inspection system to examine multiple parts more quickly. In addition to mounting inspection systems on automatic devices, multiple-axis robots can remove parts from the mould and position them for further processes.\nSpecific instances include removing of parts from the mould immediately after the parts are created, as well as applying machine vision systems. A robot grips the part after the ejector pins have been extended to free the part from the mould. It then moves them into either a holding location or directly onto an inspection system. The choice depends upon the type of product, as well as the general layout of the manufacturing equipment. Vision systems mounted on robots have greatly enhanced quality control for insert moulded parts. A mobile robot can more precisely determine the placement accuracy of the metal component, and inspect faster than a human can.", "Engineering,_Manufacturing": 1.0000042915, "qwen": "Yes"}
{"id": "27629711", "revid": "40416264", "url": "https://en.wikipedia.org/wiki?curid=27629711", "title": "Fraunhofer Competence Field Additive Manufacturing", "text": "The Fraunhofer Competence Field Additive Manufacturing integrates eighteen Fraunhofer institutes across Germany, which depending on their main focus, deal with subjects concerning additive manufacturing and represent the entire process chain. This includes the development, application and implementation of additive production processes as well as associated materials. Topics may cover all aspects of additive manufacturing, such as: materials and technologies, assessing and improving the quality of 3D printed parts, optimizing parts for various criteria (weight, stiffness, etc.) and digital workflow (slicers, adaptive machine control). \nThe network was founded as Fraunhofer Rapid Prototyping Alliance in 1998 and was relaunched as Fraunhofer Additive Manufacturing Alliance in 2008, when additive manufacturing took off as a manufacturing technology of the future. In 2021 Fraunhofer reorganizes its research areas in order to better meet the industrial requirements and the Fraunhofer Additive Manufacturing Alliance will bundle its expertise in the Fraunhofer Competence Field Additive Manufacturing. \nBased on many years of experience in fulfilling nationally and internationally industrial contracts as well as research projects, the Fraunhofer Competence Field Additive Manufacturing develops customized designs for each customer and manages complex assignments. Its current focus is on bio-medical engineering, micro-system engineering, automotive engineering & aerospace, tool making as well as handling and assembly.\nThe two main fairs every year are the Rapid.Tech 3D in June and the formnext in November. The Rapid.Tech 3D is focussed on manufacturing of end products using additive techniques and how the technology can be transferred into mass production. \nThe formnext is a global trade fair dedicated to additive manufacturing and industrial 3D printing, where experts come from a wide range of industry sectors, such as automotive, aerospace, mechanical engineering, medical technology, electrical engineering and many more.\nDirect Digital Manufacturing Conference (DDMC).\nThe Fraunhofer Competence Field Additive Manufacturing organizes the biannual DDMC, which is a cutting-edge forum for discussion on Additive Manufacturing, including its application in industry and the environmental impact of such new manufacturing technologies. Impact on health, sustainability and technology will also be discussed. DDMC brings together researchers, educators and practitioners from around the world and fosters an atmosphere conducive to developing new ideas and refining already existing research developments.\nFraunhofer-Institutes.\nThe Fraunhofer Competence Field Additive Manufacturing includes the following Fraunhofer-Institutes:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "27629935", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=27629935", "title": "Four-die forging device", "text": "Four-die forging device is a special forging tool designed for manufacturing forgings with long axis by four-side radial forging method in conventional open-die hydraulic forging press. A similar stand-alone machine is known as a radial forging machine.\nThe device is used for deformation treatment of ingots and blanks from ordinary and high-alloy steels and alloys, including hard-to-deform ones, in wide range of shapes and grades to obtain various solid and hollow forgings, including round, square and polygonal forged bars of constant and variable cross-section, blanks of smooth and stepped shafts, axles, thick-wall pipes, mechanical tube, shells, etc.\nDesign and Operation.\nThe device consists of the upper case and the lower case with the upper die and the lower die installed therein respectively, and sliders that are kinematically interconnected with the cases by means of guides of special design and hold side dies attached thereto. The device is installed on a tool table of an open-die forging press as easy as ordinary dies. Thereat, the lower case of the device is fixed to the tool table and always remains stationary while the upper case is attached to the press ram and always travels along with it. When the press ram goes up the upper die also goes up and the side dies are retracted opening the device working space whereto a work piece is fed by a manipulator. When the press ram goes down the work piece is reduced simultaneously by four dies. Then the cycle repeats.\nFrom Two Dies to Four.\nThe second half of the 19th century was marked with the appearance of hydraulic forging presses that started to replace hammers at forging works. Forging in forging presses is carried out by two dies of which one makes reciprocal movements and the other one remains stationary. This is the reason for relatively low productivity and high labour intensity of conventional forging in presses. The forging of low-ductility and hard-to-deform steels and alloys by two dies using conventional forging methods is very difficult and sometimes is practically impossible because of high tensile stresses in deformation zone leading to various forging defects and high percentage of rejected products.\nIn the 1970s the mechanical radial forging machines (RFM) started to be used for the large-scale production of long-axis forgings where a work piece is reduced in radial directions simultaneously by several pairs of dies. The process of radial forging in mechanical RFM features high productivity of forging. However small single reductions of a work piece restricted by the design of these machines lead to localization of strains mainly in surface zones of the work piece while metal in the core zone remains unworked. In 80-90s hydro-mechanical and hydraulic radial forging machines appeared that do not have the disadvantages inherent to mechanical RFM. Nevertheless, radial forging machines are very specific and very expensive equipment in comparison with multipurpose forging presses. The application of such machines at enterprises with a wide range of forgings manufactured is economically disadvantageous and inexpedient.\nThe problem of manufacturing long-axis forgings by radial forging method in open-die hydraulic forging presses can be solved with use of multi-die forging devices. First such devices different in design and principle of operation appeared in the 1980s. At present, the most widespread and famous is the four-die forging device of the above described design engineered by Ukrainian and Russian scientists. The four-die forging devices have no analogues in the world now. They are successfully used at works in Russia, Ukraine, Spain, China and Germany.\nAdvantages of Forging with Four-Die Forging Device.\nThe use of four-die forging devices in hydraulic forging presses provides for the following advantages in comparison with conventional methods of forging by two dies:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "20902587", "revid": "42964814", "url": "https://en.wikipedia.org/wiki?curid=20902587", "title": "Maryland Steamer", "text": "The Maryland Steamer automobile was manufactured in Luke, Maryland in 1900 and 1901\nHistory.\nThe Maryland Automobile Manufacturing company developed a runabout with a two-cylinder vertical steam engine and a chain drive. In December 1900 the factory was blown down by gale force winds. The factory was insured and production continued in 1901. The Company offered bodies as a Tourist Carriage, Runabout, Surrey, Phaeton, Omnibus, Delivery Wagon and Racing Machine. The company was reported in receivership by May 1901. The factory became a bottling plant.\nExternal Links.\nMaryland Automobile Manufacturing Co. at the Virtual Steam Car Museum", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1367046", "revid": "46084433", "url": "https://en.wikipedia.org/wiki?curid=1367046", "title": "Aichi Steel", "text": "History.\nAichi Steel was one of the earliest subsidiaries of the Toyota Group. Kiichiro Toyoda, the founder of Toyota, struggled to manufacture automobiles as the steel producers were uninterested to supply his small workshop with the steel sheets for automobiles. To address the problem, Toyoda bought his own furnace that provided his company with the casting expertise and forming equipment that would shape a car. This iron workshop became the precursor to Aichi Steel.\nThe company was established in 1934 as Aichi Seiko, the steel manufacturing department of Toyoda Automatic Loom Works, the predecessor to Toyota Industries. The company derived its name from Aichi Prefecture, where Toyota's headquarters and major production facilities are located. It became an independent company in 1940 and changed its name to its present one in 1945.\nToday, Aichi Steel supplies 40% of the steel, springs and forged products for automotive use to members of the Toyota Group. This volume underscored Toyota's reliance on the partnership given the sophisticated nature of Aichi's manufacturing services, which few suppliers can replicate. In January 2016, a furnace explosion in one of Aichi's steel mills suspended production at Toyota's entire assembly plants for one week and threatened further disruptions to the company's operations for almost two months.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "71976082", "revid": "31737083", "url": "https://en.wikipedia.org/wiki?curid=71976082", "title": "Hot form quench", "text": "Hot Form Quench (HFQ®) is an industrial forming process for the production of deep drawn, precise and complex geometry ultra-high strength aluminium sheet components. It is a hot stamping process for certain grades of aluminium and has similarities to the press hardening of ultra-high strength steels. HFQ exploits viscoplasticity of aluminium at high temperatures to facilitate the production of lightweight structures, often replacing steel, composites, castings, extrusions or multiple cold formed pressings.\nHot Form Quench (HFQ) is a hot forming process for high strength aluminium sheet (typically) 2x, 6x and 7x series alloys, that was initially developed in the early 2000s by Professors Jianguo Lin and Trevor Dean at the University of Birmingham and then at Imperial College London, both in the UK.\nImpression Technologies Limited (ITL), a materials technology company based in Coventry, UK, has exclusive commercialisation rights for HFQ, and has since developed its own additional know-how and rights in this domain. At the same time as the first HFQ applications were adopted in automotive applications (the Aston Martin DB11) in 2016, other organisations in the lightweighting ecosystem joined Impression Technologies on a Horizon 2020 programme called LoCoMaTech with an aim to take the HFQ Technology towards mass volume applications. ITL has since started licensing the HFQ Technology around the world to manufacturers supplying the automotive and aerospace sectors.\nProcess.\nHot forming of aluminium alloys consists of four main steps performed on a custom-shaped sheet blank: solutionising, blank transfer, quenching and forming, and artificial aging. In the solutionising step, the blank is heated in a furnace to a temperature where the precipitates in the material dissolve. The solutionising ovens are most effective when designed with forced convection, which is a difference to those used for press hardened steel lines.\nThe pressing operation is carried out in a high speed hydraulic, servo-hydraulic or servo press in which the forming tool is cooled to create the necessary quenching to maintain the alloying elements in solid solution. The subsequent ageing process enables precipitation and increases the strength of the components to the required level, typically 300 to 500MPa yield, depending on the aluminium alloy used. Customised proprietary ageing processes have been developed to optimise corrosion performance and/or downstream joining properties\nFollowing the HFQ process, parts can be in-die trimmed or laser trimmed as is typical for press hardened steel parts, dependant on production volume. It is usual for volumes below 10,000 parts per annum to be laser trimmed because of the high cost of the trim tooling; or for higher volumes if flexibility is required for future design changes, such as hole positioning.\nAlthough a key benefit of the HFQ process is to enable the production of complex, deep drawn pressings in a single forming operation, it is possible to perform secondary cold pressing operations after the HFQ stage if required.\nApplications.\nHFQ is used where light-weighting and high levels of part integration are required where aluminium sheet is considered a suitable technical and economic proposition. HFQ can be a solution for applications ranging from several hundred to millions of parts per annum. Aluminium sheet thickness ideal for HFQ range from 0.8mm to 5.0mm.\nTypical HFQ applications target Body-in-White (BIW) structures and closures including A and B pillars, door rings, cross members, sills, dash panels, rear quarter inners, door inners, tailgate inners and under shields. Recently there has been significant interest in the use of HFQ for battery lids and casings for electric vehicles. Alloys used for these applications include the 6x and 7x series such as 6111, 6082, 6016 and 7075.\nAerospace applications are being developed that include lip skins, nacelles, fairings, wing ribs and seats. Other transportation sector applications include electric bicycles, motorcycles, and rail structures.\nIn other sectors, HFQ has been considered to replace heavy castings and machined components, currently made from aluminium where light-weighting or material utilisation are critical factors.\nA critical consideration in the design of HFQ components is ensuring that the forming simulation is accurate, which is greatly influenced by the quality of the material cards for each alloy and the type of lubricant used.\nAdvantages and disadvantages.\nHFQ’s main advantage is superior formability for ultra-high strength aluminium alloys, that would otherwise split during conventional cold forming. This leads to extremely deep drawn parts (can be >300mm), sharp radii (r/t of 0.8 of has been demonstrated) and high levels of part integration versus cold formed pressings. In addition, HFQ enables the manufacture of parts from high and ultra-high strength aluminium, which for strength dominant applications facilitates significant weight reductions of circa 20% versus some lower strength cold formed aluminium alloys. When compared to superplastic forming, which is well-established, HFQ can offer significantly higher production speeds (of up to 4 parts per minute) and a wider range of aluminium grades. Secondary benefits of HFQ include the ability to use lower cost and more widely available F Temper alloy feedstocks and even use highly recycled alloys.\nThe main disadvantage of HFQ compared to cold forming is a higher cycle time, although the technology is now being utilised for medium/high volume applications as its adoption becomes more widespread.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "53267005", "revid": "1893804", "url": "https://en.wikipedia.org/wiki?curid=53267005", "title": "Design for verification", "text": "Design for verification (DfV) is a set of engineering guidelines to aid designers in ensuring right first time manufacturing and assembly of large-scale components. The guidelines were developed as a tool to inform and direct designers during early stage design phases to trade off estimated measurement uncertainty against tolerance, cost, assembly, measurability and product requirements.\nBackground.\nIncreased competition in the aerospace market has placed additional demands on aerospace manufacturers to reduce costs, increase product flexibility and improve manufacturing efficiency. There is a knowledge gap within the sphere of digital to physical dimensional verification and on how to successfully achieve dimensional specifications within real-world assembly factories that are subject to varying environmental conditions. \nThe DfV framework is an engineering principle to be used within low rate and high value and complexity manufacturing industries to aid in achieving high productivity in assembly via the effective dimensional verification of large volume structures, during final assembly. The DfV framework has been developed to enable engineers to design and plan the effective dimensional verification of large volume, complex structures in order to reduce failure rates and end-product costs, improve process integrity and efficiency, optimise metrology processes, decrease tooling redundancy and increase product quality and conformance to specification. The theoretical elements of the DfV methods were published in 2016, together with their testing using industrial case studies of representative complexity. The industrial tests published on ScienceDirect proved that by using the new design for verification methods alongside the traditional ‘design for X’ toolbox, the resultant process achieved improved tolerance analysis and synthesis, optimized large volume metrology and assembly processes and more cost-effective tool and jig design.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "53292889", "revid": "1461430", "url": "https://en.wikipedia.org/wiki?curid=53292889", "title": "Applications of 3D printing", "text": "In recent years, 3D printing has developed significantly and can now perform crucial roles in many applications, with the most common applications being manufacturing, medicine, architecture, custom art and design, and can vary from fully functional to purely aesthetic applications. \n3D printing processes are finally catching up to their full potential, and are currently being used in manufacturing and medical industries, as well as by sociocultural sectors which facilitate 3D printing for commercial purposes. There has been a lot of hype in the last decade when referring to the possibilities we can achieve by adopting 3D printing as one of the main manufacturing technologies. Utilizing this technology would replace traditional methods that can be costly and time consuming. There have been case studies outlining how the customization abilities of 3D printing through modifiable files have been beneficial for cost and time effectiveness in a healthcare applications.\nThere are different types of 3D printing such as Fused filament fabrication (FFF), Stereolithography (SLA), Selective Laser Sintering (SLS), polyjet printing, Multi-Jet Fusion (MJF), Direct Metal Laser Sintering (DMLS), and Electron Beam Melting (EBM).\nFor a long time, the issue with 3D printing was that it has demanded very high entry costs, which does not allow profitable implementation to mass-manufacturers when compared to standard processes. However, recent market trends spotted have found that this is finally changing. As the market for 3D printing has shown some of the quickest growth within the manufacturing industry in recent years. The applications of 3D printing are vast due to the ability to print complex pieces with a use of a wide range of materials. Materials can range from plastic and polymers as thermoplastic filaments, to resins, and even stem cells.\nManufacturing applications.\nAM technologies found applications starting in the 1980s in product development, data visualization, rapid prototyping, and specialized manufacturing. Their expansion into production (job production, mass production, and distributed manufacturing) has been under development in the decades since. Industrial production roles within the metalworking industries achieved significant scale for the first time in the early 2010s. Since the start of the 21st century there has been a large growth in the sales of AM machines, and their price has dropped substantially. According to Wohlers Associates, a consultancy, the market for 3D printers and services was worth $2.2 billion worldwide in 2012, up 29% from 2011. McKinsey predicts that additive manufacturing could have an economic impact of $550 billion annually by 2025. There are many applications for AM technologies, including architecture, construction (AEC), industrial design, automotive, aerospace, military, engineering, dental and medical industries, biotech (human tissue replacement), fashion, footwear, jewelry, eyewear, education, geographic information systems, food, and many other fields.\nAdditive manufacturing's earliest applications have been on the toolroom end of the manufacturing spectrum. For example, rapid prototyping was one of the earliest additive variants, and its mission was to reduce the lead time and cost of developing prototypes of new parts and devices, which was earlier only done with subtractive toolroom methods such as CNC milling and turning, and precision grinding, far more accurate than 3d printing with accuracy down to 0.00005\" and creating better quality parts faster, but sometimes too expensive for low accuracy prototype parts. With technological advances in additive manufacturing, however, and the dissemination of those advances into the business world, additive methods are moving ever further into the production end of manufacturing in creative and sometimes unexpected ways. Parts that were formerly the sole province of subtractive methods can now in some cases be made more profitably via additive ones. In addition, new developments in RepRap technology allow the same device to perform both additive and subtractive manufacturing by swapping magnetic-mounted tool heads.\nCloud-based additive manufacturing.\nAdditive manufacturing in combination with cloud computing technologies allows decentralized and geographically independent distributed production. Cloud-based additive manufacturing refers to a service-oriented networked manufacturing model in which service consumers are able to build parts through Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS), Hardware-as-a-Service (HaaS), and Software-as-a-Service (SaaS). Distributed manufacturing as such is carried out by some enterprises; there is also a services like 3D Hubs that put people needing 3D printing in contact with owners of printers.\nSome companies offer online 3D printing services to both commercial and private customers, working from 3D designs uploaded to the company website. 3D-printed designs are either shipped to the customer or picked up from the service provider.\nThere are many open source websites that have downloadable STL files which are able to be modified or printed as is. Files ranging from functional tools to aesthetic figurines are available to the general public. Open source files can be beneficial for the user as the printed object can be more cost effective than commercial counterparts.\nMass customization.\nCompanies have created services where consumers can customize objects using simplified web based customization software, and order the resulting items as 3D printed unique objects. This now allows consumers to create custom cases for their mobile phones. Nokia has released the 3D designs for its case so that owners can customize their own case and have it 3D printed.\nRapid manufacturing.\nAdvances in RP technology have introduced materials that are appropriate for final manufacture, which has in turn introduced the possibility of directly manufacturing finished components. One advantage of 3D printing for rapid manufacturing lies in the relatively inexpensive production of small numbers of parts.\nRapid manufacturing is a new method of manufacturing and many of its processes remain unproven. 3D printing is now entering the field of rapid manufacturing and was identified as a \"next level\" technology by many experts in a 2009 report. One of the most promising processes looks to be the adaptation of selective laser sintering (SLS), or direct metal laser sintering (DMLS) some of the better-established rapid prototyping methods. , however, these techniques were still very much in their infancy, with many obstacles to be overcome before RM could be considered a realistic manufacturing method.\nThere have been patent lawsuits concerning 3-D printing for manufacturing.\nRapid prototyping.\nIndustrial 3D printers have existed since the early 1980s and have been used extensively for rapid prototyping and research purposes. These are generally larger machines that use proprietary powdered metals, casting media (e.g. sand), plastics, paper or cartridges, and are used for rapid prototyping by universities and commercial companies.\nResearch.\n3D printing can be particularly useful in research labs due to its ability to make specialized, bespoke geometries. In 2012 a proof of principle project at the University of Glasgow, UK, showed that it is possible to use 3D printing techniques to assist in the production of chemical compounds. They first printed chemical reaction vessels, then used the printer to deposit reactants into them. They have produced new compounds to verify the validity of the process, but have not pursued anything with a particular application.\nUsually, the FDM process is used to print hollow reaction vessels or microreactors. If the 3D print is performed within an inert gas atmosphere, the reaction vessels can be filled with highly reactive substances during the print. The 3D printed objects are air- and watertight for several weeks. By the print of reaction vessels in the geometry of common cuvettes or measurement tubes, routine analytical measurements such as UV/VIS-, IR- and NMR-spectroscopy can be performed directly in the 3D printed vessel.\nIn addition, 3D printing has been used in research labs as alternative method to manufacture components for use in experiments, such as magnetic shielding and vacuum components with demonstrated performance comparable to traditionally produced parts.\nFood.\nAdditive manufacturing of food is being developed by squeezing out food, layer by layer, into three-dimensional objects. A large variety of foods are appropriate candidates, such as chocolate and candy, and flat foods such as crackers, pasta, and pizza. NASA has considered the versatility of the concept, awarding a contract to the Systems and Materials Research Consultancy to study the feasibility of printing food in space. NASA is also looking into the technology in order to create 3D printed food to limit food waste and to make food that are designed to fit an astronaut's dietary needs. A food-tech startup Novameat from Barcelona 3D-printed a steak from peas, rice, seaweed, and some other ingredients that were laid down criss-cross, imitating the intracellular proteins. One of the problems with food printing is the nature of the texture of a food. For example, foods that are not strong enough to be filed are not appropriate for 3D printing.\nAgile tooling.\nAgile tooling is the process of using modular means to design tooling that is produced by additive manufacturing or 3D printing methods to enable quick prototyping and responses to tooling and fixture needs. Agile tooling uses a cost-effective and high-quality method to quickly respond to customer and market needs. It can be used in hydro-forming, stamping, injection molding and other manufacturing processes.\nMedical applications.\nSurgical uses of 3D printing-centric therapies have a history beginning in the mid-1990s with anatomical modeling for bony reconstructive surgery planning. By practicing on a tactile model before surgery, surgeons were more prepared and patients received better care. Patient-matched implants were a natural extension of this work, leading to truly personalized implants that fit one unique individual. Virtual planning of surgery and guidance using 3D printed, personalized instruments have been applied to many areas of surgery including total joint replacement and craniomaxillofacial reconstruction with great success. Further study of the use of models for planning heart and solid organ surgery has led to increased use in these areas. Hospital-based 3D printing is now of great interest and many institutions are pursuing adding this specialty within individual radiology departments. The technology is being used to create unique, patient-matched devices for rare illnesses. One example of this is the bioresorbable trachial splint to treat newborns with tracheobronchomalacia developed at the University of Michigan. Several devices manufacturers have also begun using 3D printing for patient-matched surgical guides (polymers). The use of additive manufacturing for serialized production of orthopedic implants (metals) is also increasing due to the ability to efficiently create porous surface structures that facilitate osseointegration. Printed casts for broken bones can be custom-fitted and open, letting the wearer scratch any itches, wash and ventilate the damaged area. They can also be recycled.\nFused filament fabrication (FFF) has been used to create microstructures with a three-dimensional internal geometry. Sacrificial structures or additional support materials are not needed. Structure using polylactic acid (PLA) can have fully controllable porosity in the range 20%–60%. Such scaffolds could serve as biomedical templates for cell culturing, or biodegradable implants for tissue engineering. \n3D printing has been used to print patient-specific implant and device for medical use. Successful operations include a titanium pelvis implanted into a British patient, titanium lower jaw transplanted to a Dutch patient, and a plastic tracheal splint for an American infant. The hearing aid and dental industries are expected to be the biggest areas of future development using custom 3D printing technology. In March 2014, surgeons in Swansea used 3D printed parts to rebuild the face of a motorcyclist who had been seriously injured in a road accident. Research is also being conducted on methods to bio-print replacements for lost tissue due to arthritis and cancer .\n3D printing technology can now be used to make exact replicas of organs. The printer uses images from patients' MRI or CT scan images as a template and lays down layers of rubber or plastic. These models can be used to plan difficult operations, as was the case in May 2018, when surgeons used a 3D printed replica of a kidney to practice a kidney transplant on a three-year-old boy.\nThermal degradation during 3D printing of resorbable polymers, same as in surgical sutures, has been studied, and parameters can be adjusted to minimize the degradation during processing. Soft pliable scaffold structures for cell cultures can be printed.\nIn 3D printing, computer-simulated microstructures are commonly used to fabricate objects with spatially varying properties. This is achieved by dividing the volume of the desired object into smaller subcells using computer aided simulation tools and then filling these cells with appropriate microstructures during fabrication. Several different candidate structures with similar behaviours are checked against each other and the object is fabricated when an optimal set of structures are found. Advanced topology optimization methods are used to ensure the compatibility of structures in adjacent cells. This flexible approach to 3D fabrication is widely used across various disciplines from biomedical sciences where they are used to create complex bone structures and human tissue to robotics where they are used in the creation of soft robots with movable parts. 3D printing also finds its uses more and more in design and fabrication of laboratory apparatuses.\n3D printing technology can also be used to produce personal protective equipment, also known as PPE, is worn by medical and laboratory professionals to protect themselves from infection when they are treating patients. Examples of PPE include face masks, face shields, connectors, gowns, and goggles. The most popular forms of 3D printed PPE are face masks, face shields, and connectors.\nNowadays, Additive Manufacturing is also employed in the field of pharmaceutical sciences. Different techniques of 3D printing (e.g. FDM, SLS, Inkjet Printing etc) are utilized according to their respective advantages and drawbacks for various applications regarding drug delivery.\nBio-printing.\nIn 2006, researchers at Cornell University published some of the pioneer work in 3D printing for tissue fabrication, successfully printing hydrogel bio-inks. The work at Cornell was expanded using specialized bioprinters produced by Seraph Robotics, Inc., a university spin-out, which helped to catalyze a global interest in biomedical 3D printing research.\n3D printing has been considered as a method of implanting stem cells capable of generating new tissues and organs in living humans. With their ability to transform into any other kind of cell in the human body, stem cells offer huge potential in 3D bioprinting. Professor Leroy Cronin of Glasgow University proposed in a 2012 TED Talk that it was possible to use chemical inks to print medicine. In 2015 the FDA approved Spritam ®, a 3D printed drug also known as levetiracetam. Currently, there are three methods of 3D printing that have been explored for the production of drug making: laser based writing systems, printing-based inkjet systems, and nozzle based systems.\n, 3D bio-printing technology has been studied by biotechnology firms and academia for possible use in tissue engineering applications in which organs and body parts are built using inkjet techniques. In this process, layers of living cells are deposited onto a gel medium or sugar matrix and slowly built up to form three-dimensional structures including vascular systems. The first production system for 3D tissue printing was delivered in 2009, based on NovoGen bioprinting technology. Several terms have been used to refer to this field of research: organ printing, bio-printing, body part printing, and computer-aided tissue engineering, among others. The possibility of using 3D tissue printing to create soft tissue architectures for reconstructive surgery is also being explored.\nIn 2013, Chinese scientists began printing ears, livers and kidneys, with living tissue. Researchers in China have been able to successfully print human organs using specialized 3D bioprinters that use living cells instead of plastic . Researchers at Hangzhou Dianzi University designed the \"3D bioprinter\" dubbed the \"Regenovo\". Xu Mingen, Regenovo's developer, said that it can produce a miniature sample of liver tissue or ear cartilage in less than an hour, predicting that fully functional printed organs might take 10 to 20 years to develop.\nMedical devices.\nOn October 24, 2014, a five-year-old girl born without fully formed fingers on her left hand became the first child in the UK to have a prosthetic hand made with 3D printing technology. Her hand was designed by US-based e-NABLE, an open source design organisation which uses a network of volunteers to design and make prosthetics mainly for children. The prosthetic hand was based on a plaster cast made by her parents. A boy named Alex was also born with a missing arm from just above the elbow. The team was able to use 3D printing to upload an e-NABLE Myoelectric arm that runs off of servos and batteries that are actuated by the electromyography muscle. With the use of 3D printers, e-NABLE has so far distributed thousands of plastic hands to children. Another example is Open Bionics, a company that makes fully functional bionic arms through 3D printing technology. 3D printing allows Open Bionics to create personalized designs for their clients, as there can be different colours, textures, patterns, and even \"Hero Arms\" that emulate superheroes like Ironman or characters from Star Wars.\nPrinted prosthetics have been used in rehabilitation of crippled animals. In 2013, a 3D printed foot let a crippled duckling walk again. 3D printed hermit crab shells let hermit crabs inhabit a new style home. A prosthetic beak was another tool developed by the use of 3D printing to help aid a bald eagle named Beauty, whose beak was severely mutilated from a shot in the face. Since 2014, commercially available titanium knee implants made with 3D printer for dogs have been used to restore the animals' mobility. Over 10,000 dogs in Europe and the United States have been treated after only one year.\nIn February 2015, FDA approved the marketing of a surgical bolt which facilitates less-invasive foot surgery and eliminates the need to drill through bone. The 3D printed titanium device, 'FastForward Bone Tether Plate' is approved to use in correction surgery to treat bunion. In October 2015, the group of Professor Andreas Herrmann at the University of Groningen has developed the first 3D printable resins with antimicrobial properties. Employing stereolithography, quaternary ammonium groups are incorporated into dental appliances that kill bacteria on contact. This type of material can be further applied in medical devices and implants.\n3D Printing has been especially beneficial for the creation of patient specific prosthetics for large or invasive surgeries. In a case study published in 2020 about the benefits of 3D printing for hip prostheses, three patients with acetabular defects needed revisions of total hip arthroplasty (THA). 3D printing was utilized to produce prostheses that were specific to each of the three patients and their complex bone defect, which resulted in better post procedure recovery and prognosis of the individual.\nIn a case study about the applications of 3D printing in occupational therapy, the aspect of customization and quick fabrication at a low cost is utilized in different tools such as customized scissor handles and bottle openers for someone with hand motor complications. Beverage holders, writing guides, grip strengtheners, and other occupational therapy items were designed, printed, and compared with commercially available counterparts in a cost analysis. It found that the 3D printed items were on average 10.5 times more cost effective than commercial alternatives.\n3D printing for medical devices can range from human prosthetics applications, to animal prostheses, to medical machine tools: On June 6, 2011, the company Xilloc Medical together with researchers at the University of Hasselt, in Belgium had successfully printed a new jawbone for an 83-year-old Dutch woman from the province of Limburg. 3D printing has been used to produce prosthetic beaks for eagles, a Brazilian goose named Victoria, and a Costa Rican toucan called Grecia. In March 2020, the Isinnova company in Italy printed 100 respirator valves in 24 hours for a hospital that lacked them in the midst of the coronavirus outbreak. It's clear that 3D printing technology is beneficial in many areas of healthcare.\nPharmaceutical Formulations.\nIn May 2015 the first formulation manufactured by 3D printing was produced. In August 2015 the FDA approved the first 3D printed tablet. Binder-jetting into a powder bed of the drug allows very porous tablets to be produced, which enables high drug doses in a single formulation that rapidly dissolves and is easily absorbed. This has been demonstrated for Spritam, a reformulation of levetiracetam for the treatment of epilepsy.\nAdditive Manufacturing has been increasingly utilized by scientists in the pharmaceutical field. However, after the first FDA approval of a 3D printed formulation, scientific interest for 3D applications in drug delivery grew even bigger. Research groups around the world are studying different ways of incorporating drugs within a 3D printed formulation, for example by incorporating poorly water-soluble drugs in self-emulsifying systems or emulsion gels. 3D printing technology allows scientists to develop formulations with a personalized approach, i.e. dosage forms tailored specifically to an individual patient. Moreover, according to the advantages of the diverse utilized techniques, formulations with various properties can be achieved. These may contain multiple drugs in a single dosage form, multi-compartmental designs, drug delivery systems with distinct release characteristics ,etc. During the earlier years, researchers have mainly focused on the Fused Deposition Modelling (FDM) technique. Nowadays, other printing techniques such as Selective Laser Sintering (SLS), Stereolithography (SLA) and Semi-solid extrusion (SSE) are also gaining traction and are being used for pharmaceutical applications.\nIndustrial applications.\nApparel.\n3D printing has entered the world of clothing with fashion designers experimenting with 3D-printed bikinis, shoes, and dresses. In commercial production Nike used 3D printing to prototype and manufactured the 2012 Vapor Laser Talon football shoe for players of American football, and New Balance is 3D manufacturing custom-fit shoes for athletes.\n3D printing has come to the point where companies are printing consumer grade eyewear with on-demand custom fit and styling (although they cannot print the lenses). On-demand customization of glasses is possible with rapid prototyping.\nHowever, comments have been made in academic circles as to the potential limitation of the human acceptance of such mass customized apparel items due to the potential reduction of brand value communication.\nIn the world of high fashion courtiers such as Karl Lagerfeld designing for Chanel, Iris van Herpen and Noa Raviv working with technology from Stratasys, have employed and featured 3d printing in their collections. Selections from their lines and other working with 3d printing were showcased at\nthe 2016 Metropolitan Museum of Art Anna Wintour Costume Center, exhibition \"Manus X Machina\".\nDuring the COVID-19 pandemic, the Ukrainian-American undergraduate Karina Popovich founded Markers for COVID-19 which used 3D printing to create face shields, face masks and other items of personal protective equipment.\nFootwear.\n3D Printed Footwear is a relatively new concept in the fashion industry, but it has quickly gained recognition for its innovative designs and customizable features. The history of 3D printed footwear can be traced back to the early 2000s, when 3D printing technology first became available to the public.\nThere are several benefits of using 3D printing technology in shoe manufacturing, including:\nOverall, 3D printing technology offers several advantages to shoe manufacturers, allowing them to create more customized and innovative designs while also reducing waste and improving sustainability. As the technology continues to develop, we can expect to see even more benefits in the future.\nOne of the pioneers in 3D printed footwear was Janne Kyttanen, a Finnish designer who created a series of 3D printed shoes in 2008. These shoes were made using a nylon powder material and were produced using a selective laser sintering (SLS) process.\nAnother early adopter of 3D printed footwear was Continuum Fashion, a design company that created the first fully 3D printed shoes in 2010. These shoes were made using a combination of 3D modeling software and 3D printing technology, and were designed to be both fashionable and functional.\nFeetz is a footwear company that specializes in creating custom-fit shoes using 3D printing technology. The company was founded in 2013 by entrepreneur Lucy Beard, who wanted to create a more sustainable and personalized approach to footwear. Their shoes were the first to be fully 3D printed.\nIn 2015, Adidas introduced its first 3D printed shoe, the Futurecraft 3D, with a midsole created using a 3D printing process called Stereolithography (SLA). \nFUSED Footwear was founded in 2017, and is known for its unique and innovative shoe designs that are made using 3D printing technology. The company uses a proprietary 3D printing process that allows them to create shoes with intricate and eye-catching designs that would be difficult or impossible to achieve with traditional manufacturing methods. One of the key features of FUSED Footwear's designs is the use of a flexible, rubber-like material that conforms to the wearer's foot for a comfortable and supportive fit. This material is also durable and long-lasting, making FUSED Footwear's shoes a practical choice for everyday wear.\nStarted in Germany in 202, Zellerfeld uses a combination of 3D scanning and printing technologies to create custom-fit shoes for their customers. Their shoes are made using a biodegradable, eco-friendly material that is both lightweight and durable.\nOverall, 3D Printed Footwear is an exciting new trend in the fashion industry that offers endless possibilities for customization and innovation. With brands like Zellerfeld and Fused Footwear leading the way, we can expect to see even more exciting developments in this field in the coming years.\nIndustrial art and jewelry.\n3D printing is used to manufacture moulds for making jewelry, and even the jewelry itself. 3D printing is becoming popular in the customisable gifts industry, with products such as personalized models of art and dolls, in many shapes: in metal or plastic, or as consumable art, such as 3D printed chocolate.\nAutomotive industry.\nIn early 2014, Swedish supercar manufacturer Koenigsegg announced the One:1, a supercar that utilizes many components that were 3D printed. In the limited run of vehicles Koenigsegg produces, the One:1 has side-mirror internals, air ducts, titanium exhaust components, and complete turbocharger assemblies that were 3D printed as part of the manufacturing process.\nUrbee is the name of the first car in the world car mounted using the technology 3D printing (its bodywork and car windows were \"printed\"). Created in 2010 through the partnership between the US engineering group Kor Ecologic and the company Stratasys (manufacturer of printers Stratasys 3D), it is a hybrid vehicle with futuristic look.\nIn 2014, Local Motors debuted Strati, a functioning vehicle that was entirely 3D Printed using ABS plastic and carbon fiber, except the powertrain. In 2015, the company produced another iteration known as the LM3D Swim that was 80 percent 3D-printed. In 2016, the company has used 3D printing in the creation of automotive parts, such ones used in Olli, a self-driving vehicle developed by the company.\nIn May 2015 Airbus announced that its new Airbus A350 XWB included over 1000 components manufactured by 3D printing.\n3D printing is also being utilized by air forces to print spare parts for planes. In 2015, a Royal Air Force Eurofighter Typhoon fighter jet flew with printed parts. The United States Air Force has begun to work with 3D printers, and the Israeli Air Force has also purchased a 3D printer to print spare parts.\nConstruction, home development.\nThe use of 3D printing to produce scale models within architecture and construction has steadily increased in popularity as the cost of 3D printers has reduced. This has enabled faster turn around of such scale models and allowed a steady increase in the speed of production and the complexity of the objects being produced.\nConstruction 3D printing, the application of 3D printing to fabricate construction components or entire buildings has been in development since the mid-1990s, development of new technologies has steadily gained pace since 2012 and the sub-sector of 3D printing is beginning to mature.\nFirearms.\nIn 2012, the US-based group Defense Distributed disclosed plans to \"design a working plastic gun that could be downloaded and reproduced by anybody with a 3D printer.\" Defense Distributed has also designed a 3D printable AR-15 type rifle lower receiver (capable of lasting more than 650 rounds) and a 30-round M16 magazine. The AR-15 has multiple receivers (both an upper and lower receiver), but the legally controlled part is the one that is serialized (the lower, in the AR-15's case). Soon after Defense Distributed succeeded in designing the first working blueprint to produce a plastic gun with a 3D printer in May 2013, the United States Department of State demanded that they remove the instructions from their website. After Defense Distributed released their plans, questions were raised regarding the effects that 3D printing and widespread consumer-level CNC machining may have on gun control effectiveness.\nIn 2014, a man from Japan became the first person in the world to be imprisoned for making 3D printed firearms. Yoshitomo Imura posted videos and blueprints of the gun online and was sentenced to jail for two years. Police found at least two guns in his household that were capable of firing bullets.\nComputers and robots.\n3D printing can also be used to make laptops and other computers and cases. For example, Novena and VIA OpenBook standard laptop cases. I.e. a Novena motherboard can be bought and be used in a printed VIA OpenBook case.\nOpen-source robots are built using 3D printers. Double Robotics grant access to their technology (an open SDK). On the other hand, 3&DBot is an Arduino 3D printer-robot with wheels and ODOI is a 3D printed humanoid robot.\nSoft sensors and actuators.\n3D printing has found its place in soft sensors and actuators manufacturing inspired by 4D printing concept. The majority of the conventional soft sensors and actuators are fabricated using multistep low yield processes entailing manual fabrication, post-processing/assembly, and lengthy iterations with less flexibility in customization and reproducibility of final products. 3D printing has been a game changer in these fields with introducing the custom geometrical, functional, and control properties to avoid the tedious and time-consuming aspects of the earlier fabrication processes.\nSpace.\nThe Zero-G Printer, the first 3D printer designed to operate in zero gravity, was built under a joint partnership between NASA Marshall Space Flight Center (MSFC) and Made In Space, Inc. In September 2014, SpaceX delivered the zero-gravity 3D printer to the International Space Station (ISS). On December 19, 2014, NASA emailed CAD drawings for a socket wrench to astronauts aboard the ISS, who then printed the tool using its 3D printer. Applications for space offer the ability to print parts or tools on-site, as opposed to using rockets to bring along pre-manufactured items for space missions to human colonies on the moon, Mars, or elsewhere. The second 3D printer in space, the European Space Agency's Portable On-Board 3D Printer (POP3D) was planned to be delivered to the International Space Station before June 2015. By 2019, a commercial-built recycling facility was scheduled to be sent to the International Space Station to take in plastic waste and unneeded plastic parts and convert them into spools of feedstock for the space station additive manufacturing facility to be used to build manufactured-in-space parts.\nIn 2016, Digital Trends reported that BeeHex was building a 3D food printer for crewed missions to Mars.\nMost construction planned on asteroids or planets will be bootstrapped somehow using the materials available on those objects. 3D printing is often one of the steps in this bootstrapping. The Sinterhab project is researching a lunar base constructed by 3D printing using lunar regolith as a base material. Instead of adding a binding agent to the regolith, researchers are experimenting with microwave sintering to create solid blocks from the raw material.\nProjects like these have been investigated for construction of off-Earth habitats.\nSociocultural applications.\nIn 2005, a rapidly expanding hobbyist and home-use market was established with the inauguration of the open-source RepRap and Fab@Home projects. Virtually all home-use 3D printers released to-date have their technical roots in the ongoing RepRap Project and associated open-source software initiatives. In distributed manufacturing, one study has found that 3D printing could become a mass market product enabling consumers to save money associated with purchasing common household objects. For example, instead of going to a store to buy an object made in a factory by injection molding (such as a measuring cup or a funnel), a person might instead print it at home from a downloaded 3D model.\nArt and jewellery.\nIn 2005, academic journals began to report on the possible artistic applications of 3D printing technology, being used by artists such as Martin John Callanan at The Bartlett school of architecture. By 2007 the mass media followed with an article in the \"Wall Street Journal\" and \"Time\" magazine, listing a printed design among their 100 most influential designs of the year. During the 2011 London Design Festival, an installation, curated by Murray Moss and focused on 3D Printing, was held in the Victoria and Albert Museum (the V&A). The installation was called \"Industrial Revolution 2.0: How the Material World will Newly Materialize\".\nAt the 3DPrintshow in London, which took place in November 2013 and 2014, the art sections had works made with 3D printed plastic and metal. Several artists such as Joshua Harker, Davide Prete, Sophie Kahn, Helena Lukasova, Foteini Setaki showed how 3D printing can modify aesthetic and art processes. In 2015, engineers and designers at MIT's Mediated Matter Group and Glass Lab created an additive 3D printer that prints with glass, called \"G3DP\". The results can be structural as well as artistic. Transparent glass vessels printed on it are part of some museum collections.\nThe use of 3D scanning technologies allows the replication of real objects without the use of moulding techniques that in many cases can be more expensive, more difficult, or too invasive to be performed, particularly for precious artwork or delicate cultural heritage artifacts where direct contact with the moulding substances could harm the original object's surface.\n3D selfies.\nA 3D photo booth such as the Fantasitron located at Madurodam, the miniature park, generates 3D selfie models from 2D pictures of customers. These selfies are often printed by dedicated 3D printing companies such as Shapeways. These models are also known as 3D portraits, 3D figurines or mini-me figurines.\nCommunication.\nEmploying additive layer technology offered by 3D printing, Terahertz devices which act as waveguides, couplers and bends have been created. The complex shape of these devices could not be achieved using conventional fabrication techniques. Commercially available professional grade printer EDEN 260V was used to create structures with minimum feature size of 100 µm. The printed structures were later DC sputter coated with gold (or any other metal) to create a Terahertz Plasmonic Device.\nIn 2016 artist/scientist Janine Carr Created the first 3d printed vocal percussion (beatbox) as a waveform, with the ability to play the soundwave by laser, along with four vocalised emotions these were also playable by laser.\nDomestic use.\nSome early consumer examples of 3d printing include the 64DD released in 1999 in Japan. As of 2012, domestic 3D printing was mainly practiced by hobbyists and enthusiasts. However, little was used for practical household applications, for example, ornamental objects. Some practical examples include a working clock and gears printed for home woodworking machines among other purposes. Web sites associated with home 3D printing tended to include backscratchers, coat hooks, door knobs, etc.\nThe open source Fab@Home project has developed printers for general use. They have been used in research environments to produce chemical compounds with 3D printing technology, including new ones, initially without immediate application as proof of principle. The printer can print with anything that can be dispensed from a syringe as liquid or paste. The developers of the chemical application envisage both industrial and domestic use for this technology, including enabling users in remote locations to be able to produce their own medicine or household chemicals.\n3D printing is now working its way into households, and more and more children are being introduced to the concept of 3D printing at earlier ages. The prospects of 3D printing are growing, and as more people have access to this new innovation, new uses in households will emerge.\nThe OpenReflex SLR film camera was developed for 3D printing as an open-source student project.\nEducation and research.\n3D printing, and open source 3D printers in particular, are the latest technology making inroads into the classroom. 3D printing allows students to create prototypes of items without the use of expensive tooling required in subtractive methods. Students design and produce actual models they can hold. The classroom environment allows students to learn and employ new applications for 3D printing. RepRaps, for example, have already been used for an educational mobile robotics platform.\nSome authors have claimed that 3D printers offer an unprecedented \"revolution\" in STEM education. The evidence for such claims comes from both the low cost ability for rapid prototyping in the classroom by students, but also the fabrication of low-cost high-quality scientific equipment from open hardware designs forming open-source labs. Engineering and design principles are explored as well as architectural planning. Students recreate duplicates of museum items such as fossils and historical artifacts for study in the classroom without possibly damaging sensitive collections. Other students interested in graphic designing can construct models with complex working parts easily. 3D printing gives students a new perspective with topographic maps. Science students can study cross-sections of internal organs of the human body and other biological specimens. And chemistry students can explore 3D models of molecules and the relationship within chemical compounds. The true representation of exactly scaled bond length and bond angles in 3D printed molecular models can be used in organic chemistry lecture courses to explain molecular geometry and reactivity.\nAccording to a recent paper by Kostakis et al., 3D printing and design can electrify various literacies and creative capacities of children in accordance with the spirit of the interconnected, information-based world.\nFuture applications for 3D printing might include creating open-source scientific equipment.\nNowadays, the demand of 3D printing keep on increasing in order to fulfill the demands in producing parts with complex geometry at a lower development cost. The increasing demands 3D printing parts in industry would eventually lead to the 3D printed parts repairing activity and secondary process such as joining, foaming and cutting. This secondary process need to be developed in order to support the growth of the 3D printing application in the future. From the research, FSW is proven able to be used as one of the methods to join the metal 3D printing materials. By using proper FSW tools and correct parameter setting a sound and defect-free weld can be produced in order to join the metal 3D printing materials.\nEnvironmental use.\nIn Bahrain, large-scale 3D printing using a sandstone-like material has been used to create unique coral-shaped structures, which encourage coral polyps to colonize and regenerate damaged reefs. These structures have a much more natural shape than other structures used to create artificial reefs, and, unlike concrete, are neither acid nor alkaline with neutral pH.\nCultural heritage.\nIn the last several years 3D printing has been intensively used by in the cultural heritage field for preservation, restoration and dissemination purposes. Many Europeans and North American Museums have purchased 3D printers and actively recreate missing pieces of their relics.\nScan the World is the largest archive of 3D printable objects of cultural significance from across the globe. Each object, originating from 3D scan data provided by their community, is optimised for 3D printing and free to download on MyMiniFactory. Through working alongside museums, such as The Victoria and Albert Museum and private collectors, the initiative serves as a platform for democratizing the art object.\nThe Metropolitan Museum of Art and the British Museum have started using their 3D printers to create museum souvenirs that are available in the museum shops. Other museums, like the National Museum of Military History and Varna Historical Museum, have gone further and sell through the online platform Threeding digital models of their artifacts, created using Artec 3D scanners, in 3D printing friendly file format, which everyone can 3D print at home.\nSpecialty materials.\nConsumer grade 3D printing has resulted in new materials that have been developed specifically for 3D printers. For example, filament materials have been developed to imitate wood in its appearance as well as its texture. Furthermore, new technologies, such as infusing carbon fiber into printable plastics, allowing for a stronger, lighter material. In addition to new structural materials that have been developed due to 3D printing, new technologies have allowed for patterns to be applied directly to 3D printed parts. Iron oxide-free Portland cement powder has been used to create architectural structures up to 9 feet in height.", "Engineering,_Manufacturing": 0.9982815981, "qwen": "Yes"}
{"id": "53292993", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=53292993", "title": "3D printing processes", "text": "A variety of processes, equipment, and materials are used in the production of a three-dimensional object via additive manufacturing. 3D printing is also known as additive manufacturing, because the numerous available 3D printing process tend to be additive in nature, with a few key differences in the technologies and the materials used in this process.\nSome of the different types of physical transformations which are used in 3D printing include melt extrusion, light polymerization, continuous liquid interface production and sintering.\nTypes of 3D printing processes.\nThere are many different 3D printing processes, that can be grouped into seven categories:\nEach process and piece of equipment has pros and cons associated with it. These usually involve aspects such as speed, costs, versatility with respect to feedstock material, geometrical limitations and tolerances, as well as a mechanical and appearance properties of the products such as strength, texture and color.\nThe variety of processes and equipment allows for numerous uses by amateurs and professionals alike. Some lend themselves better toward industry use (in this case the term Additive Manufacturing is preferred) whereas others make 3D printing accessible to the average consumer. Some printers are large enough to fabricate buildings whilst others tend to micro and nanoscale sized objects and in general many different technologies can be exploited to physically produce the designed objects.\nProcesses.\nSeveral 3D printing processes have been invented since the late 1970s. The printers were originally large, expensive, and highly limited in what they could produce.\nA large number of additive processes are now available. The main differences between processes are in the way layers are deposited to create parts and in the materials that are used. Some methods melt or soften the material to produce the layers, for example. selective laser melting (SLM) or direct metal laser sintering (DMLS), selective laser sintering (SLS), fused deposition modeling (FDM), or fused filament fabrication (FFF), while others cure liquid materials using different sophisticated technologies, such as stereolithography (SLA). With laminated object manufacturing (LOM), thin layers are cut to shape and joined (e.g., paper, polymer, metal). Particle deposition using inkjet technology prints layers of material in the form of individual drops. Each drop of solid ink from hot-melt material actually prints one particle or one object. Color hot-melt inks print individual drops of CMYK on top of each other to produce a single color object with 1-3 layers melted together. Complex 3D models are printed with many overlapping drops fused together into layers as defined by the sliced CAD file. Inkjet technology allows 3D models to be solid or open cell structures as defined by the 3D printer inkjet print configuration. Each method has its own advantages and drawbacks, which is why some companies offer a choice of powder and polymer for the material used to build the object. Others sometimes use standard, off-the-shelf business paper as the build material to produce a durable prototype. The main considerations in choosing a machine are generally speed, costs of the 3D printer, of the printed prototype, choice and cost of the materials, and color capabilities.\nPrinters that work directly with metals are generally expensive. However less expensive printers can be used to make a mold, which is then used to make metal parts.\nMaterial jetting.\nA nozzle with liquid material can be drawn over an absorbent surface to wick out material, electrostatically pulled from a larger jet orifice, pressurized to stream material or fluid pressure surged to expel short burst of fluid in the form of spray or individual drops. A fountain pen with nib tip is an example of wicking material. A hose is an example of streaming fluid. A pump short burst is an example of drop or spray ejection.\nNozzles can be made of any material and can be single nozzle with one fluid chamber or multi-nozzle with single or multi-fluid chambers. Today's inkjet printer products can be any variation of these inkjet styles.\nInk material for inkjets only needs to be a low enough viscosity to allow the fluid to pass through the nozzle opening. Materials can be melted to be liquid. These are called Hot-melt inks. In all cases the inkjet inks must be three-dimensional on the printed surface to produce a Z height component for a 3D object.\nInkjet was pioneered by Teletype which introduced the electrostatic pull Inktronic teleprinter in 1966. The printer had 40 jets that offered a break-through speed of 120 characters per second.\nContinuous inkjets were popular in the 1950-1960's before Drop-On-Demand inkjets were invented in 1972. Continuous three-dimensional inks were wax based and low temperature metal alloy's. Printing with these hot-melt inks produced alpha-numeric characters that were solid and raised, but no one recognized them as 3D printing. In 1971, a young engineer, Johannes Gottwald patented a liquid metal recorder that printed large characters in metal for signage, but Teletype Corp ignored the discovery. Braille was printed with wax inks but never commercialized in the 1960s.\nDrop-on-demand (DOD) inkjets were invented in 1972 using piezoelectric \"squeeze\" technology to pump out one drop per squeeze. Only water-based inks were used in these early DOD jets. Experimentation was done with many orifice shapes, diameters and multiple nozzle holes per inkjet tube. Single nozzle inkjets were called \"Alpha Jets\" at Exxon Office Systems where printing was researched by many early inventors who were hired to improve printing. The Alpha jet was rejected for being too complex. Multi-jet printheads were designed and incorporated by this group.\nA small company in New Hampshire, R.H. Research, owned by Robert Howard researched printing from 1982 -1983 and decided the single-nozzle inkjet was a possible fit and he then contacted an inventor at Exxon who named Al Hock as a good choice for this project. Al Hock invited Tom Peer and Dave Lutz to join him in New Hampshire to look into this new venture and they accepted the job offer. Dave Lutz contacted two jet people still at Exxon, Jim and Kathy McMahon and they also accepted offers to be founders in this venture later to be named Howtek, Inc. Within a few months the Alpha jets made by the new Howtek team were working fine. Howtek management chose to change the glass nozzles to Tefzel based on the inkjet test results. Tefzel allowed the inkjet to work at high temperature with the new Thermoplastic Hot-melt inks and run with no vibrations in the nozzle structure to generate stray drops. Each squeeze produced one drop over a frequency range o 1–16,000 drops per second. The nozzles were manufacturable and the Pixelmaster was born. There were 32 inkjet single nozzles per printhead, printing 4 colors (8 jets per color) CMYK. The mechanism was a printhead rotating at 121 rpm and placing uniform size and shaped drops precisely in place as subtractive color text and image printing for the graphics industry. This technology of hot-melt inks printing layers of CMYK was a precursor to a 3D patent by Richard Helinski. A few years later(1993) the patent was licensed first by Sanders Prototype, Inc.,(Renamed Solidscape, Inc) a manufacturer of the first desktop Rapid Prototype printer in the industry, the Modelmaker 6 Pro. This printer and newer products use these Howtek style inkjets and thermoplastic inks. Models printed with the Thermoplastic were perfect for investment casting with no ash during burnout. Thermoplastic ink drop printing is accurate and precise giving high quality surface finish models popular with jewelers and detail sensitive CAD designers. The Howtek inkjets designed to print a page in 4 minutes were now printing in some case for 4 days straight. The first printer was sold in 1993 to Hitchner Corporations, Metal Casting Technology R&D group where they printer golf club heads and parts for automobile engines.\nMaterial extrusion.\nFused filament fabrication (FFF), also known under the trademarked term fused deposition modeling (FDM), derives from automatic polymeric foil hot air welding system, hot-melt gluing and automatic gasket deposition. Such principle has been further developed by S. Scott Crump in the late 1980s and was commercialized in 1990 by Stratasys. After the patent on this technology expired, a large open-source development community developed and both commercial and DIY variants utilizing this type of 3D printer appeared known as the RepRap project (for self-replicating rapid prototyper). As a result, the price of this technology has dropped by two orders of magnitude since its creation, and it has become the most common form of 3D printing.\nIn fused deposition modeling, the model or part is produced by extruding small beads or streams of material which harden immediately to form layers. A filament of thermoplastic or other low melting point material or mixture is fed into an extrusion nozzle head (3D printer extruder), where the filament is heated to its melting temperature and extruded onto a build table. More recently, fused pellet deposition (or fused particle deposition) has been developed, where particles or pellets of plastic replace the need to use filament. The nozzle head heats the material and turns the flow on and off. Typically stepper motors or servo motors are employed to move the extrusion head and adjust the flow. The printer usually has 3 axes of motion. A computer-aided manufacturing (CAM) software package is used to generate the G-Code that is sent to a microcontroller which controls the motors.\nPlastic is the most common material for such printing. Various polymers may be used, including acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polylactic acid (PLA), high-density polyethylene (HDPE), PC/ABS, polyphenylsulfone (PPSU) and high impact polystyrene (HIPS). In general, the polymer is in the form of a filament fabricated from virgin resins. There are multiple projects in the open-sourced community aimed at processing post-consumer plastic waste into filament. These involve machines used to shred and extrude the plastic material into filament such as recyclebots. Additionally, fluoropolymers such as PTFE tubing are used in the process due to the material's ability to withstand high temperatures. This ability is especially useful in transferring filaments.\nMetal and glass may both be used for 3-D printing as well, though they are much more expensive and generally used for works of art. However, the development of WAAM (wire arc additive manufacturing) has reduced the costs of metal 3-D printing.\nFDM is somewhat restricted in the variation of shapes that may be fabricated. For example, FDM usually cannot produce stalactite-like structures, since they would be unsupported during the build. Otherwise, a thin support must be designed into the structure, which can be broken away during finishing. Usually, the software that converts the 3D model into a set of flat layers, called slicer, takes care of the addition of these supports and some other resources to allow the fabrication of this kind of shapes.\nPowder bed fusion.\nAnother 3D printing approach is the selective fusing of materials in a granular bed. The technique fuses parts of the layer and then moves upward in the working area, adding another layer of granules and repeating the process until the piece has built up. This process uses the unfused media to support overhangs and thin walls in the part being produced, which reduces the need for temporary auxiliary supports for the piece. For example, in selective heat sintering, a thermal printhead applies heat to layers of powdered thermoplastic; when a layer is finished, the powder bed moves down, and an automated roller adds a new layer of material which is sintered to form the next cross-section of the model; using a less intense thermal printhead instead of a laser, makes this a cheaper solution than using lasers, and can be scaled down to desktop sizes.\nLaser sintering techniques include selective laser sintering (SLS), with both metals and polymers (e.g., PA, PA-GF, Rigid GF, PEEK, PS, Alumide, Carbonmide, elastomers), and direct metal laser sintering (DMLS).\nSelective Laser Sintering (SLS) was developed and patented by Dr. Carl Deckard and Dr. Joseph Beaman at the University of Texas at Austin in the mid-1980s, under sponsorship of DARPA. A similar process was patented without being commercialized by R. F. Housholder in 1979.\nSelective laser melting (SLM) does not use sintering for the fusion of powder granules but will completely melt the powder using a high-energy laser to create fully dense materials in a layer-wise method that has mechanical properties similar to those of conventional manufactured metals.\nElectron beam melting (EBM) is a similar type of additive manufacturing technology for metal parts (e.g. titanium alloys). EBM manufactures parts by melting metal powder layer by layer with an electron beam in a high vacuum. Unlike metal sintering techniques that operate below melting point, EBM parts are void-free.\nBinder jetting.\nThe binder jetting 3D printing technique is the deposition of a binding adhesive agent onto layers of material, usually powdered. The materials can be ceramic-based or metal. This method is also known as inkjet 3D printing system. To produce the piece, the printer builds the model using a head that moves over the platform base and deposits, one layer at a time, by spreading a layer of powder (plaster, or resins) and printing a binder in the cross-section of the part using an inkjet-like process. This is repeated until every layer has been printed. This technology allows the printing of full color prototypes, overhangs, and elastomer parts. The strength of bonded powder prints can be enhanced with wax or thermoset polymer impregnation.\nStereolithography.\n The Stereolithography (SLA) process is based on light curing (photopolymerization) of liquid materials into a solid shape; it was patented in 1986 by Chuck Hull.\nIn this process a vat of liquid polymer is exposed to controlled lighting (like a laser or a digital light projector) under safelight conditions. Most commonly the exposed liquid polymer hardens through cross-linking driven by the addition reaction of carbon carbon double bonds in acrylates. Polymerization occurs when photopolymers are exposed to light when photopolymers contain chromophores, otherwise, the addition of molecules that are photosensitive are utilized to react with the solution to begin polymerization. Polymerization of monomers lead to cross-linking, which creates a polymer. Through these covalent bonds, the property of the solution is changed. The build plate then moves down in small increments and the liquid polymer is again exposed to light. The process repeats until the model has been built. The liquid polymer is then drained from the vat, leaving the solid model. The EnvisionTEC \"Perfactory\" is an example of a DLP rapid prototyping system.\nInkjet printer systems like the \"Objet PolyJet\" system spray photopolymer materials onto a build tray in ultra-thin layers (between 16 and 30 μm) until the part is completed. Each photopolymer layer is cured with UV light after it is jetted, producing fully cured models that can be handled and used immediately, without post-curing. The gel-like support material, which is designed to support complicated geometries, is removed by hand and water jetting. It is also suitable for elastomers. There is another type of inkjet printing system available in the market that can print a photopolymer in a layer-by-layer manner, with intermediate UV curing, to produce ophthalmic corrective lenses. No support structures are required in this case, as ophthalmic lenses do not need overhangs. Luxexcel, a Dutch company, has commercialized this technology and printing platform. \nUltra-small features can be made with the 3D micro-fabrication technique used in multiphoton photopolymerisation. This approach uses a focused laser to trace the desired 3D object into a block of gel. Due to the nonlinear nature of photo excitation, the gel is cured to a solid only in the places where the laser was focused while the remaining gel is then washed away. Feature sizes of under 100 nm are easily produced, as well as complex structures with moving and interlocked parts.\nYet another approach uses a synthetic resin that is solidified using LEDs.\nIn Mask-image-projection-based stereolithography, a 3D digital model is sliced by a set of horizontal planes. Each slice is converted into a two-dimensional mask image. The mask image is then projected onto a photocurable liquid resin surface and light is projected onto the resin to cure it in the shape of the layer. The technique has been used to create objects composed of multiple materials that cure at different rates. In research systems, the light is projected from below, allowing the resin to be quickly spread into uniform thin layers, reducing production time from hours to minutes. Commercially available devices such as Objet Connex apply the resin via small nozzles.\nContinuous liquid interface production (CLIP) is another form of additive manufacturing that uses the DLP based photo polymerization process to create smooth-sided solid objects of a wide variety of shapes. The continuous process of CLIP begins with a pool of liquid photopolymer resin. Part of the pool bottom is transparent to ultraviolet light (the \"window\"). Like DLP systems before it, ultraviolet light beam shines through the window, illuminating the precise cross-section of the object. The light causes the resin to solidify. The object rises slowly enough to allow resin to flow under and maintain contact with the bottom of the object. CLIP is different from traditional DLP processes, due to an oxygen-permeable membrane which lies below the resin, creating a \"dead zone\" (persistent liquid interface) preventing the resin from attaching to the window (photopolymerization is inhibited between the window and the polymerizer).\nUnlike stereolithography, the printing process is considered continuous by its founders and considerably faster than traditional DLP processes, enabling the production of parts in minutes instead of hours.\nRecently, the use of stereolithographic 3D printing techniques has been developed further to allow for the additive manufacturing of ceramic materials. Successful 3D printing of ceramics using stereolithography is achieved through the photopolymerisation of preceramic polymers to yield silicon based ceramics of a class known more widely as polymer derived ceramics, including silicon carbide and silicon oxycarbide.\nComputed axial lithography.\nComputed axial lithography is a method for 3D printing based on reversing the principle of computed tomography (CT) to create prints in photo-curable resin. It was developed by a collaboration between the University of California, Berkeley with Lawrence Livermore National Laboratory. Unlike other methods of 3D printing it does not build models through depositing layers of material like fused deposition modelling and stereolithography, instead it creates objects using a series of 2D images projected onto a cylinder of resin. It is notable for its ability to build objects much more quickly than other methods using resins and the ability to embed objects within the prints.\nLiquid additive manufacturing.\nLiquid additive manufacturing (LAM) is an additive manufacturing technique which deposits a liquid or highly viscous material (e.g. Liquid Silicone Rubber) onto a build surface to create an object, which is then vulcanised using heat to harden it. The process was originally created by Adrian Bowyer and was then built upon by German RepRap.\nLamination.\nIn some printers, paper can be used as the build material, resulting in a lower cost to print. During the 1990s some companies marketed printers that cut cross-sections out of special adhesive coated paper using a carbon dioxide laser and then laminated them together.\nIn 2005 Mcor Technologies Ltd developed a different process using ordinary sheets of office paper, a tungsten carbide blade to cut the shape, and selective deposition of adhesive and pressure to bond the prototype.\nThere are also a number of companies selling printers that print laminated objects using thin plastic and metal sheets.\nUltrasonic Consolidation (UC) or Ultrasonic Additive Manufacturing (UAM) is a low temperature additive manufacturing or 3D printing technique for metals.\nDirected Energy Deposition (DED).\nPowder-fed directed-energy deposition.\nIn powder-fed directed-energy deposition, a high-power laser is used to melt metal powder supplied to the focus of the laser beam. The laser beam typically travels through the center of the deposition head and is focused to a small spot by one or more lenses. The build occurs on an X-Y table which is driven by a tool path created from a digital model to fabricate an object layer by layer. The deposition head is moved up vertically as each layer is completed. Some systems even make use of 5-axis or 6-axis systems (\"i.e.\" articulated arms) capable of delivering material on the substrate (a printing bed, or a pre-existing part) with few to no spatial access restrictions. Metal powder is delivered and distributed around the circumference of the head or can be split by an internal manifold and delivered through nozzles arranged in various configurations around the deposition head. A hermetically sealed chamber filled with inert gas or a local inert shroud gas (sometimes both combined) are often used to shield the melt pool from atmospheric oxygen, to limit oxidation and better control the material properties. The powder fed directed energy process is similar to Selective Laser Sintering, but the metal powder is projected only where material is being added to the part at that moment. The laser beam is used to heat up and create a \"melt pool\" on the substrate, in which the new powder is injected quasi-simultaneously. The process supports a wide range of materials including titanium, stainless steel, aluminum, tungsten, and other specialty materials as well as composites and functionally graded material. The process can not only fully build new metal parts but can also add material to existing parts for example for coatings, repair, and hybrid manufacturing applications. LENS (Laser Engineered Net Shaping), which was developed by Sandia National Labs, is one example of the Powder Fed - Directed Energy Deposition process for 3D printing or restoring metal parts.\nMetal wire processes.\nLaser-based wire-feed systems, such as Laser Metal Deposition-wire (LMD-w), feed wire through a nozzle that is melted by a laser using inert gas shielding in either an open environment (gas surrounding the laser), or in a sealed chamber. Electron beam freeform fabrication uses an electron beam heat source inside a vacuum chamber.\nIt is also possible to use conventional gas metal arc welding attached to a 3D stage to 3-D print metals such as steel, bronze and aluminum. Low-cost open source RepRap-style 3-D printers have been outfitted with Arduino-based sensors and demonstrated reasonable metallurgical properties from conventional welding wire as feedstock.\nSelective Powder Deposition (SPD).\nIn selective powder deposition, build and support powders are selectively deposited into a crucible, such that the build powder takes the shape of the desired object and support powder fills the rest of the volume in the crucible. Then an infill material is applied, such that it comes in contact with the build powder. Then the crucible is fired up in a kiln at the temperature above the melting point of the infill, but below the melting points of the powders. When the infill melts, it soaks the build powder. But it doesn't soak the support powder, because the support powder is chosen to be such that it is not wettable by the infill. If at the firing temperature, the atoms of the infill material and the build powder are mutually defusable, such as in case of copper powder and zinc infill, then the resulting material will be a uniform mixture of those atoms, in this case, bronze. But if the atoms are not mutually defusable, such as in case of tungsten and copper at 1100°C, then the resulting material will be a composite. To prevent shape distortion, the firing temperature must be below the solidus temperature of the resulting alloy.\nPrinters.\nIndustry use.\nAs of October 2012, additive manufacturing systems were on the market that ranged from $2,000 to $500,000 in price and were employed in industries including aerospace, architecture, automotive, defense, and medical replacements, among many others. As of 2018, 3-D printers have dropped in cost to as little $100 and low-cost higher quality desktop printers are approximately $2500. These types of devices are used widely in industry for prototyping, jig making, fixturing, fixing small custom components, and even additive manufacturing of actual products.\nIn addition, higher end 3-D printers have now become relatively common for production and additive manufacturing. For example, General Electric uses the high-end model to build parts for turbines. Many of these systems are used for rapid prototyping, before mass production methods are employed. Volkswagen uses 3D printers on their assembly lines to print tooling, jigs and fixtures. They estimate that 3D printers save 250,000 EURO per year in costs. One report estimates that almost 75% of desktop 3D printers made are used in industry and not by consumers.\nMilitary and defense are also incorporating the use of 3D printers. The Royal Netherlands Air Force is using desktop 3D printers at their Woensdrecht Air Force Base to make fixtures and alignment tools. In the United States, the Hill Air Force base is using 3D printed parts in repair of fighter jets.\nHigher education has proven to be a major buyer of desktop and professional 3D printers. Significant desktop 3D printer purchases by both K-12 and universities helped sustain a desktop 3D printer market that had problems in 2015–2016. As higher education is the home to research, 3D printing is being used to fabricate equipment to further research and hold down costs. For example, chemists can 3D print flow reactor systems that would otherwise be too costly to purchase. The UCL School of Pharmacy in the UK created a modular flow reactor system for chemical synthesis that can easily be 3D printed in laboratories around the world at low cost. Libraries around the world have also become locations to house smaller 3D printers for educational and community access.\nConsumer use.\nSeveral projects and companies are making efforts to develop affordable 3D printers for home desktop use. Much of this work has been driven by and targeted at DIY/Maker/enthusiast/early adopter communities, with additional ties to the academic and hacker communities.\nRepRap Project is one of the longest running projects in the desktop category. The RepRap project aims to produce a free and open source hardware (FOSH) 3D printer, whose full specifications are released under the GNU General Public License, which is capable of replicating itself by printing many of its own (plastic) parts to create more machines. RepRaps have already been shown to be able to print circuit boards and metal parts. The most popular 3D printer in the world is the Prusa i3, a RepRap printer.\nBecause of the FOSH aims of RepRap, many related projects have used their design for inspiration, creating an ecosystem of related or derivative 3D printers, most of which are also open-source designs. The availability of these open-source designs means that variants of 3D printers are easy to invent. The quality and complexity of printer designs, however, as well as the quality of kit or finished products, varies greatly from project to project. This rapid development of open source 3D printers is gaining interest in many spheres as it enables hyper-customization and the use of public domain designs to fabricate open source appropriate technology. This technology can also assist initiatives in sustainable development since technologies are easily and economically made from resources available to local communities.\nThe cost of 3D printers has decreased dramatically since about 2010, with machines that used to cost $20,000 now costing less than $1,000. For instance, as of 2013, several companies and individuals are selling parts to build various RepRap designs, with prices starting at about / . The open source Fab@Home project has developed printers for general use with anything that can be squirted through a nozzle, from chocolate to silicone sealant and chemical reactants. Printers following the project's designs have been available from suppliers in kits or in pre-assembled form since 2012 at prices in the US$2000 range. Several new 3D printers are aimed at the small, inexpensive market including the mUVe3D and Lumifold. Rapide 3D has designed a professional grade crowdsourced 3D-printer costing $1499 which has no fumes nor constant rattle during use. The 3Doodler, \"3D printing pen\", raised $2.3 million on Kickstarter with the pens selling at $99, though the 3D Doodler has been criticized for being more of a crafting pen than a 3D printer.\nAs the costs of 3D printers have come down, they are becoming more appealing financially to use for self-manufacturing of personal products. In addition, 3D printing products at home may reduce the environmental impacts of manufacturing by reducing material use and distribution impacts.\nIn addition, several RecycleBots such as the commercialized Filastruder have been designed and fabricated to convert waste plastic, such as shampoo containers and milk jugs, into inexpensive RepRap filament. There is some evidence that using this approach of distributed recycling is better for the environment.\nThe development and hyper-customization of the RepRap-based 3D printers has produced a new category of printers suitable for small business and consumer use. Manufacturers such as Solidoodle, Robo 3D, RepRapPro and Pirx 3D have introduced models and kits priced at less than $1,000, thousands less than they were in September 2012. Depending on the application, the print resolution and speed of manufacturing lies somewhere between a personal printer and an industrial printer. A list of printers with pricing and other information is maintained. Most recently, delta robots, like the TripodMaker, have been utilized for 3D printing to increase fabrication speed further. For delta 3D printers, due to its geometry and differentiation movements, the accuracy of the print depends on the position of the printer head.\nSome companies are also offering software for 3D printing, as a support for hardware manufactured by other companies.\nLarge 3D printers.\nLarge 3D printers have been developed for industrial, education, and demonstrative uses. A large delta-style 3D printer was built in 2014 by SeeMeCNC. The printer is capable of making an object with diameter of up to and up to in height. It also uses plastic pellets as the raw material instead of the typical plastic filaments used in other 3D printers.\nAnother type of large printer is Big Area Additive Manufacturing (BAAM). The goal is to develop printers that can produce a large object in high speed. A BAAM machine of Cincinnati Incorporated can produce an object at the speeds 200-500 times faster than typical 3D printers available in 2014. Another BAAM machine is being developed by Lockheed Martin with an aim to print long objects of up to to be used in aerospace industries.\nSee also Construction 3D printing\nMicroscale and nanoscale 3D printing.\nMicroelectronic device fabrication methods can be employed to perform the 3D printing of nanoscale-size objects. Such printed objects are typically grown on a solid substrate, e.g. silicon wafer, to which they adhere after printing as they are too small and fragile to be manipulated post-construction.\nIn one technique, 3D nanostructures can be printed by physically moving a dynamic stencil mask during the material deposition process, somewhat analogous to the extrusion method of traditional 3D printers. Programmable-height nanostructures with resolutions as small as 10 nm have been produced in this fashion, by metallic physical vapor deposition Mechanicalpiezo-actuator controlled stencil mask having a milled nanopore in a silicon nitride membrane.\nAnother method enhances the photopolymerization process on a much smaller scale, using finely-focused lasers controlled by adjustable mirrors. This method has produced objects with feature resolutions of 100 nm. Micron wide, millimetre long copper wires have also been printed using lasers.", "Engineering,_Manufacturing": 0.9999935627, "qwen": "Yes"}
{"id": "53293194", "revid": "1145331724", "url": "https://en.wikipedia.org/wiki?curid=53293194", "title": "India Kawasaki Motors", "text": "India Kawasaki Motors Private Limited (IKM) is an Indian motorcycle retailer. It was established in May 2010 in Pune, Maharashtra, as a wholly owned subsidiary of Kawasaki Heavy Industries Motorcycle & Engine, Japan Ltd. for imports and sales of motorcycles. Kawasaki made a technical assistance agreement with Bajaj Auto Ltd. in 1984, and cooperated to expand production and sales of motorcycles in India. In November 2016 India Kawasaki Motors decided to break ties with Bajaj Auto Ltd. for sales and service from April 2017 and sell its motorcycles through its own network.\nIndia Kawasaki Motors currently sells the Ninja 300, Ninja 400, Ninja 650, Ninja 1000, Z650, Z650 RS, Z900, ZH2, ZH2 SE, Versys 650, Versys 1000, Vulcan S, Ninja ZX-10R, Ninja H2, Ninja H2R and Ninja H2Carbon are sold through Kawasaki exclusive dealerships. In the past, Kawasaki manufactured commuter bikes such as KB100, 4S Champion, KB125, Boxer, Aspire, Caliber, Wind and Eliminator jointly with Indian partner Bajaj Auto Ltd. IKM’s annual capacity currently stands at 2,500-3,000 units.\nVehicles.\nCruiser Bike.\nvulcan s", "Engineering,_Manufacturing": 0.9996409416, "qwen": "Yes"}
{"id": "53299610", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=53299610", "title": "Tommy Gate", "text": "Tommy Gate is an American brand of hydraulic liftgate, or tail lift, manufactured by Woodbine Manufacturing Company. The company was formed in 1965 by Delbert \"Bus\" Brown and its production facility is located in Woodbine, Iowa.\nHistory.\nPrior to founding Woodbine Manufacturing Company, Delbert Brown manufactured farming equipment as Brown Manufacturing Company. After inventing what was then one of the first trenching machines, Brown Manufacturing Company was sold to Omaha Steel Works. Three years later, Brown founded Woodbine Manufacturing Company and began the Tommy Gate brand.\nExpansion.\nThe Woodbine manufacturing facility was initially built in 1965 to occupy 70,000 square feet of production space. It expanded in 1980 to 90,000 and once again in 2000 when it grew to 140,000. The most recent expansion, completed in 2011, grew the plant to an overall 200,000 square feet (including 40,000 square feet of warehouse space).", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "39335150", "revid": "9155723", "url": "https://en.wikipedia.org/wiki?curid=39335150", "title": "Bending machine (manufacturing)", "text": "A bending machine is a forming machine tool (DIN 8586). Its purpose is to assemble a bend on a workpiece. A bend is manufactured by using a bending tool during a linear or rotating move.\nThe detailed classification can be done with the help of the kinematics.\nCNC bending.\nCNC bending machines are developed for high flexibility and low setup times. Those machines are able to bend single pieces as well as small batches with the same precision and efficiency as series-produced parts in an economical way.\nUniversal bending machines – modular construction.\nUniversal bending machines consists of a basic machine that can be adjusted with little effort and used for a variety of bends. A simple plug-in system supports quick and easy exchange of tools.\nThe basic machine consists of a CNC-operated side stop, a work bench, and software for programming and operating. Its modular construction offers an affordable entry into the bending technology, because after an initial investment the machine can be customized and extended later without any conversion. That means the basic machine delivers a bending stroke, and the tool determines the kind of bending.\nBending tools.\nIn the case of bending tools they are classified by the kind of generated bends. They can be constructed to adjust the bending angle by reference, stroke measurement or angle measurement.\nCNC machines usually abstain from a reference part. They grant a high bending accuracy starting with the first work piece.\nStandard bends.\nAll bends without an extraordinary geometry belong to standard bends. The distance between a bend and the material end is quite high providing an adequate bearing area. The same with one bend to the next.\nTypical tools are a so-called bending former combined with a prisms with electronic angular measurement or an ordinary prism.\nU-bending.\nFor U-bends where tight and narrow bends are necessary, the bending former is replaced by a bending mandrel. A bending mandrel has a narrow geometry.\nOffset bending.\nOffset bending tools are used to assemble two bends with a small distance between in one step.\nEdgewise bending.\nEdge bending tools are used if the bending axis is placed parallel to the tight side of the work piece. Tools for bending on edge may include electronic angular measurement allowing a high bending accuracy.\nTorsion bending.\nTorsion tools are able to rotate the workpiece on the longitudinal axis. Alternatives are complex assembly groups with standard bends.\nAngular measurement and spring back compensation.\nFor producing single pieces as well as small batches with the same precision and efficiency as series-produced parts, a spring back compensation is helpful. A bending accuracy of +/- 0.2° starting\nfrom the first work piece is achieved due to calculated spring back compensation and the use\nof electronic tools.\nOperating mode angular measurement.\nBending prisms with electronic angular measurement technology are equipped with two flattened bending bolds. That bold rotate while bending giving a signal to the angle measurement. The measuring accuracy is about 0.1º. The computer then calculates the required final stroke and spring back of every bend is compensated regardless of material type. A high angle accuracy of +/- 0.2º is achieved instantly with the first workpiece without adjustments. Compared to adjustment by reference, material waste amounts are decreased, because even inconsistencies within a single piece of material are automatically adjusted .\nOperating mode stroke measurement.\nWherever bending prisms with electronic angular measurement are not suitable, a small distance between the bends might be a reason, bending prisms without electronic angle measurement are applied.\nIn that case the control unit can be switched from angular measurement to stroke measurement. This method allows the pre-selection of the stroke of the bending ram in mm and therefore the immersion depth of the punch into the prism. Setting accuracy is +/- 0.1 mm. A final stroke is usually not required. Further development of the stroke system enables the user to specify an angle from which the stroke is calculated by using stored stroke functions. Bending accuracy in that case is dependent on material properties such as thickness, hardness, etc. which may differ from one work piece to another.\nProgramming and principle of operation.\nProgramming is done on a PC equipped with dedicated software, which is part of the machine or connected to an external workstation. For generating a new program engineering data can be imported or pasted per mouse and keyboard. Through a graphic and menu-driven user interface previous CNC programming skills are not required. The software asks for all necessary values and checks all figures. Inputs can be corrected at any time and minimum distances are checked instantly to guard against improper inputs. The software automatically calculates the flat length of each part being bent and determines the exact position of the side stop. The part is shown on a screen.\nIdeally each program is stored in one database, so it is easy to recover them by search and sort functions.\nNetworking with the whole production line.\nA lot of organizational effort and interface management is saved, if the CNC bending machine is connected to the previous and subsequent process. For a connection to other machines and external workstations corporate interfaces have to be established.\nNetworking with a punching machine.\nIf a part is bended, in most cases a prior process was inserting holes to mount it in an assembly group.\nTherefore, a punching machine is an option. Some programs enable the operator to program both step by one software tool.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "39339569", "revid": "12023796", "url": "https://en.wikipedia.org/wiki?curid=39339569", "title": "Tapered integration", "text": "Tapered integration is a term from organization theory that refers to a mix of vertical integration and market exchange. Upstream, a producer might manufacture some of the input itself and buy the remaining portion from independent firms. Downstream, the manufacturer might sell a portion of its output through an in-house sales force and use independent sales forces to sell the remainder.\nIt is not documented when the term \"tapered integration\" was first used, though it can be found in law journals such as the Yale Law Journal as early as the 1950s, the first known use in academia being a case study by William King Norris.\nExamples.\nExamples for tapered integration are (1) Tim Hortons owning some of its retail outlets but also using franchising, (2) Coca-Cola and Pepsi both having integrated bottling subsidiaries while also relying on independent bottlers for production and distribution in some markets, or (3) BMW which uses both in-house market research from its Corporate Center Development and external market research from independent, specialized firms.", "Engineering,_Manufacturing": 0.999666214, "qwen": "Yes"}
{"id": "6693240", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=6693240", "title": "Pencil milling", "text": "Pencil milling is a cleanup toolpath generated by computer-aided manufacturing (CAM) programs to machine internal corners and fillets with smaller radius tools to remove the remaining material that are inaccessible with larger tools used for previous roughing, semi-finishing, and finishing toolpaths. The name comes from the way that a pencil could naturally be drawn along these corners. It is sometimes called a rolling ball toolpath.\nOften a constant step-over passes are derived from single pencil pass to create parallel pencil passes that are very good for cleaning up corners and fillets where excess material remains from a bigger cutter.\nGenerating pencil toolpaths.\nThere are several alternative algorithms for generating pencil passes. The method most commonly published in the academic literature involves creating tool surface offsets of the model surfaces and intersecting them to find the common line where the cutter would be in contact with two surfaces at once. An example of this implementation uses the ZMap method described by Park, et al.\nThe industrial method, used in commercial CAM software, differs substantially and works by detecting double-contact points and linking them up into a chain to form a toolpath. A double-contact point is a pair of cutter locations displaced by a tiny distance horizontally, but with a large difference in height or sudden change in contact point. These positions can be located very precisely by binary subdivision, where a cutter location created between a pair of close cutter locations will almost always be continuous with one or the other side.", "Engineering,_Manufacturing": 0.9989606142, "qwen": "Yes"}
{"id": "299182", "revid": "8798719", "url": "https://en.wikipedia.org/wiki?curid=299182", "title": "PTC Creo Elements/Pro", "text": "Creo Parametric, formerly known, together with Creo Elements/Pro, as Pro/Engineer and Wildfire, is a solid modeling or CAD, CAM, CAE, and associative 3D modeling application, running on Microsoft Windows. \nCreo Parametric should not to be confused with Creo Elements/Direct Modeling, which was CoCreate ME10 (2D) and or ME30 (3D) CAD Products. The ex-CoCreate CAD Products are now owned by PTC and offered as \"Creo Elements/Direct Drafting\" and Creo Elements/Direct Modling\".\nCreo Parametric is an application of a suite of 10 that provide collaborative solid modeling, assembly modeling, 2D orthographic views, finite element analysis, parametric modeling, sub-divisional and NURBS surface modeling, Drafting, and NC and tooling functionality for mechanical designers. \nCreo Elements/Pro compete directly with CATIA, SolidWorks, NX/Solid Edge, Inventor/Fusion 360, IRONCAD, and Onshape. It was created by Parametric Technology Corporation (PTC) and was the first of its kind to market. \nThe software uses a specific file naming scheme, not allowing certain characters (including spaces).\nOverview.\nCreo Elements (formerly Pro/Engineer), PTC's parametric, integrated 3D CAD/CAM/CAE solution, is used by manufacturers for mechanical engineering, design and manufacturing.\nPro/Engineer was the industry's first rule-based constraint (sometimes called \"parametric\" or \"variational\") 3D CAD modeling system. The parametric modeling approach uses parameters, dimensions, features, and relationships to capture intended model behavior. This design approach can be family-based or platform-driven, where the strategy is to use engineering constraints and relationships to quickly optimize the design, or where the resulting geometry may be complex or based upon equations. Creo Elements provides a complete set of design, analysis and manufacturing capabilities on one, integral, scalable platform. These required capabilities include Solid Modeling, Surfacing, Rendering, Data Interoperability, Routed Systems Design, Simulation, Tolerance Analysis, and NC and Tooling Design.\nCreo Elements can be used to create a complete 3D digital model of manufactured goods. The models consist of 2D and 3D solid model data which can also be used downstream in finite element analysis, rapid prototyping, tooling design, and CNC manufacturing. All data are associative and interchangeable between the CAD, CAE and CAM modules without conversion. A product and its entire bill of materials (BOM) can be modeled accurately with fully associative engineering drawings, and revision control information. The associativity functionality in Creo Elements enables users to make changes in the design at any time during the product development process and automatically update the end products. This capability enables concurrent engineering – design, analysis and manufacturing engineers working in parallel – and streamlines product development processes.\nSummary of capabilities.\nCreo Elements is a software application within the CAID/CAD/CAM/CAE category.\nCreo Elements is a parametric, feature-based modeling architecture incorporated into a single database philosophy with rule-based design capabilities. It provides in-depth control of complex geometry. The capabilities of the product can be split into the three main headings of Engineering Design, Analysis and Manufacturing. This data is then documented in a standard 2D production drawing or the 3D drawing standard ASME Y14.41-2003.\nProduct Design.\nCreo Elements offers a range of tools to enable the generation of a complete digital representation of the product being designed. In addition to the general geometry tools there is also the ability to generate geometry of other integrated design disciplines such as industrial and standard pipe work and complete wiring definitions. Tools are also available to support collaborative development.\nA number of concept design tools that provide up-front Industrial Design concepts can then be used in the downstream process of engineering the product. These range from conceptual Industrial design sketches, reverse engineering with point cloud data and comprehensive free-form surface.\nAnalysis.\nCreo Elements has numerous analysis tools available and covers thermal, static, dynamic and fatigue finite element analysis along with other tools all designed to help with the development of the product. These tools include human factors, manufacturing tolerance, mould flow and design optimization. The design optimization can be used at a geometry level to obtain the optimum design dimensions and in conjunction with the finite element analysis.\nSurface Modeling.\nCreo has a good surface modeling capabilities also. Using commands like Boundary blend and Sweep we can create surface models. Advance options like Style (Interactive Surface Design Extension - ISDX) and Freestyle provide more capabilities to designer to create complicated models with ease.\nManufacturing\nBy using the fundamental abilities of the software with regards to the single data source principle, it provides a rich set of tools in the manufacturing environment in the form of tooling design and simulated CNC machining and output.\nTooling options cover specialty tools for molding, die-casting and progressive tooling design.\nRelease History.\nThe UNIX version was discontinued after 4.0, except x86-64 UNIX on Solaris. The name changed to Creo 1.0 after Pro/Engineer Wildfire 5.0 (rebranded PTC Creo Elements/Pro), took place on October 28, 2010, which coincided with PTC’s announcement of Creo, a new design software application suite.\nFor the first 10 years, PTC generally released 2 versions per year, with some exceptions. The initial release (Rev 1) was in 1988.\nSee also.\nComparable Software", "Engineering,_Manufacturing": 0.9999672174, "qwen": "Yes"}
{"id": "20088199", "revid": "16364337", "url": "https://en.wikipedia.org/wiki?curid=20088199", "title": "Flow mark", "text": "Flow marks, also known as flow lines, are molding defects that can occur in the manufacturing process of injection molding. They are best described as \"off tone\" wavy lines/streaks or patterns in the molded part around the injection ports. They commonly occur when there is a large variation between cooling speeds of sections of the material as it flows through the mold.\nPrevention Methods.\nFlow mark causes vary for specific parts and production lines due to the variability in molds, machines, and materials. For the most part they are due to varying cooling speeds of the material as it flows through the mold. The different prevention methods for varying cooling speeds are as follows: \nInjection Speed/Pressure.\nInsufficient Injection speed and pressure can cause the injected material to cool and become stiffer during the injection process which can lead to a dull finish on the surface of the part. Increasing the speed will allow the material shot to fill the mold before it cools.\nMaterial/Mold Temperature.\nA low temperature will have a similar effect as a slow injection speed due to both causing the material to stiffen before the cycle completes. Increasing the temperature of the material or mold allows the material to flow without stiffening before the cycle completes. \nIf the temperature is increased too high, there is a chance to cause a different type of injection molding defect referred to as a burn mark.\nMold Design.\nThe design of a mold is one of the most important factors in correcting defects due to it controlling most of the process. For flow marks specifically, some causes that can be addressed are varying wall thicknesses, mold gate locations, and rough flow paths. Prevention for varying wall thicknesses is to round the corner where the thickness varies. This prevents the flow rate from suddenly decreasing or changing direction. Moving the location of mold gates away from mold coolant allows the material to flow more evenly and prevent premature cooling. Flow paths in the mold should allow the material to flow smoothly through the mold to prevent drastic variation in flow rate.", "Engineering,_Manufacturing": 1.0000050068, "qwen": "Yes"}
{"id": "20104357", "revid": "32452", "url": "https://en.wikipedia.org/wiki?curid=20104357", "title": "IMCO Carbide Tool", "text": "IMCO Carbide Tool is an American manufacturing company that researches, designs and manufactures high-performance cutting tools for a variety of applications in the aerospace, automotive, medical, petrochemical, and manufacturing industries. Founded in 1977 by Lawrence R. Osburn and headquartered in Perrysburg Twp, Ohio, IMCO serves a diverse customer base of small job shops to large production operations around the world.\nHistory.\nIMCO Carbide Tool is a family-owned and -operated company founded in 1977 by Lawrence R. Osburn. With his wife and two sons, Perry and Matthew, Osburn built his business in general-purpose end mills, burs, routers and drills for the automotive and manufacturing industries.\nThe sons served as company vice presidents, until Perry succeeded his father as President in 1984, with Matthew continuing as Vice President in charge of factory set-up, production processes, hiring, training, inventory management, supplier relations and quality oversight. As the machining industry was challenged by engineered materials with difficult-to-machine characteristics and more demanding specifications and tolerances, the brothers turned their focus on developing tools to meet those challenges.\nIMCO began to research and develop end mills, working with customers to create tools capable of much higher performance with new and emerging high-speed machining technologies. Versatile tools dubbed Streaker M2 end mills were introduced in 1988. Streakers were designed especially for working in aluminum. A notoriously \"soft\" metal, aluminum tends to meld in the intense heat of the cutting zone before the chips can be evacuated. This causes the chips to congeal in the cutting zone, requiring downtime to clear the blockage and, often, replace the tool. Tests with customer shops showed that Streakers eliminate this clogging problem.\nIMCO's M7 Omega-6 end mills, introduced in 2000, were designed to resolve problems in achieving high surface finishes, especially in hard-to-machine materials. Soon thereafter, IMCO launched another new product called enDURO M5 end mills, developed especially for working in and finishing aerospace alloys (titanium, stainless steels) and high-silicon aluminum. This line includes three- and five-flute designs to accommodate varying needs for chipload, chip evacuation and finish quality.\nProducts.\nIMCO tools are designed, tested, sourced and manufactured in the U.S. for machining in a wide range of materials, such as aluminum, carbon and stainless steel, tool steels, titanium, cast iron, high-temperature alloys, copper and magnesium alloys, brass, bronze, composites, plastics, and graphite. IMCO tool categories include high-performance and general-purpose end mills, burs, drills, countersinks, rougher/finishers, reamers, routers, die trimmers and custom-made, special purpose precision tools for industrial applications. The company also performs custom modifications to off-the-shelf cutting tools.\nIMCO Carbide Tool products begin with \"blanks,\" or rods of micrograin carbide or ultra-fine micrograin carbide, because of its extreme hardness and favorable heat resistance.\nIMCO specializes in high-performance end mills designed with variable fluting. Varying flute geometries break up the harmonics, or multiple mechanical frequencies that develop as tools spin and can cause tool instability and failure. Variable fluting breaks up harmonics and keeps the tool balanced as it turns for optimum tool stability. This, in turn, enables the tool to cut with greater precision.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "62077237", "revid": "461300", "url": "https://en.wikipedia.org/wiki?curid=62077237", "title": "Leaded copper", "text": "Leaded copper is a metal alloy of copper with lead. A small amount of lead makes the copper easier to machine. Alloys with a larger amount of lead are used for bearings. Brass and bronze alloys of copper may have lead added and are then also sometimes referred to as leaded copper alloys. Leaded copper and its alloys have been used since ancient times.\nApplications.\nLeaded copper alloys are used to make electrical connectors and mechanical bearings, especially in the automotive industry where high performance and reliability are required. Mechanical bearings can have high lead content. Such high lead content alloys are unsuitable for welding or brazing.\nMachined alloys.\nAlloys with around 2-4% lead are used for machined copper applications, where the lead content lubricates the copper and makes it easier to machine. These include high-quality electrical connectors where a high current capacity and low electrical resistance are required. Such connectors are used in industrial automation and the automotive industry. Brasses (copper alloyed with zinc) may also be leaded for the same reason.\nCast and sintered alloys.\nHigh-strength casting copper alloys typically contain less than 2% lead. Bearing alloys are often cast or sintered onto a steel backing. Softer alloys with a higher lead content are also used, for example in bushes where conformance to the opposite bearing surface is important.\nSome casting alloys have over 20% lead content but, due to their toxicity, they are no longer used.\nToxicity.\nWhen lead alloys wear, lead is released into the environment. Lead is a heavy metal toxin and in recent times the use of leaded copper alloys has been reduced.\nHistory.\nSigns of leaded copper use are found in the manufacture of ancient Egyptian faience. By 1500 BC leaded copper could be found across the Old World from East Asia to Africa and Europe.\nEnigmatic entries in a Chinese manuscript, the \"Kao Gong Ji\" dating from around 300 BC, were deciphered by scholars in 2022, and seem to indicate that a pre-prepared copper-lead alloy named \"Xi\" may have been used in the preparation of ancient bronzes. Another copper-tin-lead alloy named \"Jin\" was also tentatively identified as a pre-prepared component of Chinese bronzes. This part of the manuscript relates to an attempt to standardise the quality of bronze manufacture.", "Engineering,_Manufacturing": 0.9999791384, "qwen": "Yes"}
{"id": "2023440", "revid": "27199084", "url": "https://en.wikipedia.org/wiki?curid=2023440", "title": "FR-2", "text": "FR-2 (Flame Resistant 2) is a NEMA designation for synthetic resin bonded paper, a composite material made of paper impregnated with a plasticized phenol formaldehyde resin, used in the manufacture of printed circuit boards. Its main properties are similar to NEMA grade XXXP (MIL-P-3115) material, and can be substituted for the latter in many applications.\nApplications.\nFR-2 sheet with copper foil lamination on one or both sides is widely used to build low-end consumer electronic equipment. While its electrical and mechanical properties are inferior to those of epoxy-bonded fiberglass, FR-4, it is significantly cheaper. It is not suitable for devices installed in vehicles, as continuous vibration can make cracks propagate, causing hairline fractures in copper circuit traces. Without copper foil lamination, FR-2 is sometimes used for simple structural shapes and electrical insulation.\nFabrication.\nFR-2 can be machined by drilling, sawing, milling and hot punching. Cold punching and shearing are not recommended, as they leave a ragged edge and tend to cause cracking. Tools made of high-speed steel can be used, although tungsten carbide tooling is preferred for high volume production.\nAdequate ventilation or respiration protection are mandatory during high-speed machining, as it gives off toxic vapors.", "Engineering,_Manufacturing": 0.9991913438, "qwen": "Yes"}
{"id": "6918116", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=6918116", "title": "Welding helmet", "text": "A welding helmet is a type of personal protective equipment used in performing certain types of welding to protect the eyes, face, and neck from flash burn, sparks, infrared and ultraviolet light, and intense heat. The modern welding helmet used today was first introduced in 1937 by Willson Products.\nWelding helmets are most commonly used in arc welding processes such as shielded metal arc welding, gas tungsten arc welding, and gas metal arc welding. They are necessary to prevent arc eye, a painful condition where the cornea is inflamed. Welding helmets can also prevent retina burns, which can lead to a loss of vision. Both conditions are caused by unprotected exposure to the highly concentrated infrared and ultraviolet rays emitted by the welding arc. Ultraviolet emissions from the welding arc can also damage uncovered skin, causing a sunburn-like condition in a relatively short period of welding. In addition to the radiation, gases or splashes can also be a hazard to the skin and the eyes.\nMost welding helmets include a window covered with a filter called a lens shade, through which the welder can see to work. The window may be made of tinted glass, tinted plastic, or a variable-density filter made from a pair of polarized lenses. Different lens shades are needed for different welding processes. For example, metal inert gas (MIG) and tungsten inert gas (TIG) welding are low-intensity processes, so a lighter lens shade will be preferred.\nThe shade of lens that is suitable depends on the current rating of the weld. In the United States, OSHA recommends DIN shade numbers as shown in the following table:\nSafety.\nAll welding helmets are susceptible to damages such as cracks that can compromise the protection from ultraviolet and infrared rays. In addition to protecting the eyes, the helmet protects the face from hot metal sparks generated by the arc and from UV damage. When overhead welding, a leather skull cap and shoulder cover are used to prevent head and shoulder burns.\nAuto-darkening filters.\nIn 1981, Swedish manufacturer Hornell International introduced an LCD electronic shutter that darkens automatically when sensors detect the bright welding arc, the Speedglas Auto-Darkening Filter.\nWith such electronic auto-darkening helmets, the welder no longer has to get ready to weld and then nod their head to lower the helmet over their face. The advantage is that the welder does not need to adjust the position of welding helmet manually which not only saves time but also reduces the risk of exposure to the harmful light generated by the welding process.\nIn January 2004, 3M acquired all assets of Hornell, including the Adflo and Speedglas auto darkening helmets brand name and patents. Speedglas helmets are now sold by 3M.\nANSI standards.\nIn the United States, the industry standard for welding helmets is ANSI Z87.1+ which specifies performance of a wide variety of eye protection devices. The standard requires that auto-darkening helmets provide full protection against both UV and IR even when they are not in the darkened state. The standard is voluntary, so buyers should confirm that the helmet is ANSI Z87.1 compliant (indicated by appropriate labeling).", "Engineering,_Manufacturing": 0.9988532066, "qwen": "Yes"}
{"id": "10433019", "revid": "1144984973", "url": "https://en.wikipedia.org/wiki?curid=10433019", "title": "Microoptoelectromechanical systems", "text": "Microoptoelectromechanical systems (MOEMS), also known as optical MEMS, are integrations of mechanical, optical, and electrical systems that involve sensing or manipulating optical signals at a very small size. MOEMS includes a wide variety of devices, for example optical switch, optical cross-connect, tunable VCSEL, microbolometers. These devices are usually fabricated using micro-optics and standard micromachining technologies using materials like silicon, silicon dioxide, silicon nitride and gallium arsenide.\nMerging technologies.\nMOEMS includes two major technologies, microelectromechanical systems and micro-optics. Both these two technologies independently involve in batch processing similar to integrated circuits, and micromachining similar to fabrication of microsensor.\nParallel with MEMS developments and even earlier, sensor technology advanced to microsensors and joining with microactuators. Development of microsensors and microactuators were also due to a mother technology of micromachining. Micromachining is the root of everything we have today in high technology. This technology was never credited in history as it deserved. It was commercially used during the 1960s in Switzerland, for micromachining quartz orders of magnitudes harder than micromachining silicon. MEMS acronym was so powerful during the 1980s, that with no choice microsensors and microactuators that included micromachining, all joined MEMS.\nHistory of MOEMS.\nDuring 1991-1993, Dr. M. Edward Motamedi, a former Rockwell International innovator in the areas of both microelectromechanical systems and micro-optics, used internally the acronym of MOEMS for microoptoelectromechanical systems. This was to distinguish between optical MEMS and MOEMS, where optical MEMS could include bulk optics but MOEMS is truly based on microtechnology where MOEMS devices are batch-processed exactly like integrated circuits, but this is not true in most cases for optical MEMS.\nIn 1993, Dr. Motamedi officially introduced MOEMS for the first time, as the powerful combination of MEMS and micro-optics, in an invited talk at the SPIE Critical Reviews of Optical Science and Technology conference in San Diego. In this talk Dr. Motamedi introduced the figure below, for showing that MOEMS is the interaction of three major microtechnologies; namely micro-optics, micromechanics, and microelectronics.", "Engineering,_Manufacturing": 0.9995324612, "qwen": "Yes"}
{"id": "28290397", "revid": "36731198", "url": "https://en.wikipedia.org/wiki?curid=28290397", "title": "Boring bar", "text": "A boring bar is a tool used in metalworking and woodworking. Boring is a technique used in many aspects of building. Woodworkers have used boring as a form of drilling for centuries. In woodworking, the boring tool is static in size and used to form circular plunge cuts. In metalworking, boring is slightly different in that the hole that results need not be circular. In metal boring the tool can be plunged and dragged on the X or Y axes to create a slot or asymmetrical hole or channel, or it may be moved only in an up-and-down motion (on the Z axis) to create a perfect circular hole.\nComponents.\nModern boring tools have three primary components although many differing designs. The parts include the body, bar holder and dial screw (graduated micro screw). The body, made of solid stock, has two basic parts. The top part threads or presses into the supporting shank. The lower part (\"bar holder\") is connected via dovetail, T-slots or a smooth notch with an adjustment for bore diameter via the \"dial screw\". As the dial screw is adjusted, the cutting bit/s are moved further out, creating a larger cut. This also can create some slight distortion if the cutting tool is moved further than the boring head is designed to support, if there is undue wear in the bearings supporting the tool or if the tool speed is too great for the off-balance effect caused by moving the tool too far from center. This is called \"unbalanced gyroscope precession\". Once the dial screw has been adjusted to give the proper cut a set screw is generally used to prevent any additional movement of the cutting head. The third basic part is the \"boring tool\". Boring tools can be mounted vertically or horizontally in many boring head designs.\nBoring machines.\nBoring can be done on mills, lathes or drill press machines, either with a boring head or with just a boring tool. The shorter the distance between the tool holder and the material, the less distortion created from vibration or unbalanced gyroscopic effects. The greater the distance (static or dynamic mounts) the more flex in the tool or an increase in the imbalance of a moving tool. Use of a boring head increases the mass of the tool holder and decreases the distance. If a vibration is created it will be at a higher frequency and the deflection of the tool from the desired path will be much smaller and easier to erase through repetitive tool passes. In the case of a dynamic tool (mill or press), the balance of the tool can be adjusted with counterweights if the tool is mounted perpendicular to the shaft or the tool length can be decreased.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "28304311", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=28304311", "title": "Della Ferrera", "text": "Della Ferrera was an Italian motorcycle manufacturer active from 1909 to 1948. Four-valve motorcycles built by the company won events in the Trofeo Turistico Nazionale, at Cremona, and elsewhere. The company built a prototype for a cyclecar in 1924. The only model was a Cyclecar and was only produced in 1924. A four-cylinder two-stroke engine with a displacement of 707 cm³ provided the drive. The vehicle featured a four-speed gearbox and four-wheel brakes. The design-related top speed was given as 80 km/h. The Officine Meccanica Giuseppe Meldi took over the model in 1927 as the basis for its own vehicles.\nFrom 1909, Della Ferrera was building a very sturdy Motorcycle that they were able to provide 100.000 KM warranty. Until the 1st world-war, Della Ferrera was one of the primary Motorcycle makers in Italy. The Motorcycles were made by hand, which was more common at the time. Therefore, the number of motorcycles built was low. Most of the parts were made by the brothers Della Ferrera, except for the tires and parts of the ignition, including the carburetors.", "Engineering,_Manufacturing": 0.9974123836, "qwen": "Yes"}
{"id": "3956800", "revid": "7617837", "url": "https://en.wikipedia.org/wiki?curid=3956800", "title": "Workcell", "text": "A workcell is an arrangement of resources in a manufacturing environment to improve the quality, speed and cost of the process. Workcells are designed to improve these by improving process flow and eliminating waste. They are based on the principles of Lean Manufacturing as described in \"The Machine That Changed the World\" by Womack, Jones and Roos.\nHistory.\nClassical manufacturing management approaches dictate that costs be lowered by breaking the process into steps, and ensuring that each of these steps minimizes cost and maximizes efficiency. This discrete approach has resulted in machines placed apart from each other to maximize the efficiency and throughput of each machine. The traditional accounting for machine capitalization is based on the number of parts produced, and this approach reinforces the idea of lowering the cost of each machine (by having them produce as many parts as possible.) Increasing the number of parts (WIP) adds waste in areas such as Inventory and Transportation.\nLarge amounts of excess Inventory often now accumulate between the machines in the process for reasons to do with 'unbalanced' line capacities and batch processing. In addition, the parts must now be transported between the machines. An increase in the number of machines involved also will reduce each worker's multi-skilling proficiency (since that would need them to learn how to operate multiple machines, and they too will need to move between those machines.)\nLean Manufacturing focuses on optimizing the end-to-end process as a whole. This enables a focus in the process on creating a finished product at the lowest cost (instead of lowering the cost of each step.) A common approach to achieving this is known as the workcell. Machines involved in building a product are placed next to each other to minimize transportation of both parts and people (an L-shaped desk with upper shelves is a good office example, which enables many types of office equipment to be within the reach of a worker). This will minimize waste in both transportation and in the storage of excess inventory.\nAt first glance, lean workcells may appear to be similar to traditional workcells, but they are inherently different. For instance, lean workcells must be designed for minimal wasted motion, which refers to any unnecessary time and effort required to assemble a product. Excessive twists or turns, uncomfortable reaches or pickups, and unnecessary walking all contribute to wasted motion and may put error inducing stress upon the operator. Workcells can often be reconfigured easily to allow the adaptation of the process to fit takt time. This flexibility allows the work content to be adapted as demand or product mix changes.\nAnother Lean approach is to aim to have flexible manufacturing through small production lot sizes since this smooths production. Small lot sizes usually increases transportation waste, but this can be eliminated if machines are back-to-back in a workcell.\nImplementation.\nThe implementation of workcells can reduce costs by an order of magnitude (90%).\nIn software development, the core of the workcell is the cross-functional team. This team differs from a more traditional waterfall team:", "Engineering,_Manufacturing": 1.0000056028, "qwen": "Yes"}
{"id": "29017963", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=29017963", "title": "Selective laser melting", "text": "Selective laser melting (SLM) is one of many proprietary names for a metal additive manufacturing (AM) technology that uses a bed of powder with a source of heat to create metal parts. Also known as direct metal laser sintering (DMLS), the ASTM standard term is powder bed fusion (PBF). PBF is a rapid prototyping, 3D printing, or additive manufacturing technique designed to use a high power-density laser to melt and fuse metallic powders together.\nHistory.\nSelective which means the part is fully dense. This process is in all points very similar to other SLM processes, and is often considered as an SLM process. Among the companies that manufacture machines with SLM technology we find SLM solutions, owner of the SLM brand, EOS, Renishaw, DMG Mori, Concept laser, TRUMPF, Sisma, 3D Systems, 3D4MEC.\nA similar process is electron beam melting (EBM), which uses an electron beam as the energy source.\nProcess.\nSelective laser melting is able to process a variety of alloys, allowing prototypes to be functional hardware made out of the same material as production components. Since the components are built layer by layer, it is possible to design complex freeform geometries, internal features and challenging internal passages that could not be produced using conventional manufacturing techniques such as casting or otherwise machined. SLM produces fully dense durable metal parts that work well as both functional prototypes or end-use production parts.\nThe process starts by slicing the 3D CAD file data into layers, usually from 20 to 100 micrometers thick, creating a 2D cross-section of each layer; this file format is the industry standard .stl file used on most layer-based 3D printing or stereolithography technologies. This file is then loaded into a file preparation software package that assigns parameters, values and physical supports that allow the file to be interpreted and built by different types of additive manufacturing machines.\nWith selective laser melting, thin layers of atomized metal powder are evenly distributed using a re-coating mechanism onto a substrate plate, usually metal, that is fastened to an indexing platform that moves in the vertical (Z) axis. This takes place inside a chamber containing a tightly controlled atmosphere of inert gas, either argon or nitrogen at oxygen levels below 1000 parts per million. Once each layer has been distributed, each 2D slice of the part geometry is fused by selectively melting the powder. This is accomplished with a high-power laser beam, usually an ytterbium fiber laser with hundreds of watts. The laser beam is directed in the X and Y directions with two high frequency scanning mirrors and remains in focus along the layer utilising an F-Theta lens arrangement. The laser energy is intense and focused enough to permit full melting (fusion) of the particles to fore a solid structure. The process is repeated layer after layer until the part is complete.\nSLM machines predominantly uses a high-powered Yb-fiber optic laser with standard laser powers ranging from 100 - 1000W. Inside the build chamber area, there is a material dispensing platform and a build platform along with a recoater system (blade or roller) used to evenly spread new powder across the build platform. . Parts are built up additively layer by layer, typically using layers 30-60 micrometers thick.\nMaterials.\nSelective laser melting (SLM) machines can operate with a work space up to 1 m (39.37 in) in X, Y and Z. Some of the materials being used in this process can include Ni based super alloys, copper, aluminum, stainless steel, tool steel, cobalt chrome, titanium and tungsten. SLM is especially useful for producing tungsten parts because of the high melting point and high ductile-brittle transition temperature of this metal. In order for the material to be used in the process it must exist in atomized form (powder form). These powders are generally gas atomized prealloys, being the most economical process to obtain spherical powders on an industrial scale. Sphericity is desired because it guarantees a high flowability and packing density, which translates into fast and reproducible spreading of the powder layers. To further optimize flowability, narrow grain size distributions with a low percentage of fine particles like 15 - 45 µm or 20 - 63 µm are typically employed. Currently available alloys used in the process include AISI 316L, AISI 304, C67, F53, H13, 17-4 PH and 15-5 stainless steel, maraging steel, cobalt chromium, inconel 625 and 718, copper-based alloys (CW510 Brass, Ecobrass, Bronze), aluminum AlSi10Mg, and titanium Ti6Al4V.\nThe mechanical properties of samples produced using selective laser melting sintering differ from those manufactured using casting. AlSiMg samples produced using direct metal laser sintering exhibit a higher yieldengineering than those constructed of commercial as-cast A360.0 alloy by 43% when constructed along the xy-plane and 36% along the z-plane. While the yield strength of AlSiMg has been shown to increase in both the xy-plane and z-plane, the elongation at break decreases along the build direction. These improvement of the mechanical properties of the direct metal laser sintering samples has been attributed to a very fine microstructure.\nAdditionally, industry pressure has added more superalloy powders to the available processing including AM108.  It is not only the Print operation and orientation that provides a change in material properties, it is also the required post processing via Hot Isostatic Pressure (HIP) Heat Treat and shot peen that change mechanical properties to a level of noticeable difference in comparison to equiaxed cast or wrought materials.  Based on research done at the Tokyo Metropolitan University, it is shown that creep rupture and ductility are typically lower for additive printed Ni based superalloys compared to wrought or cast material. The directionality of print is a major influencing factor along with grain size. Additionally, wear properties are typically better as seen with the studies done on additive Inconel 718 due to surface condition; the study also demonstrated the laser power's influence on density and microstructure. Material Density that is generated during the laser processing parameters can further influence crack behavior such that crack reopening post HIP process is reduced when density is increased. It is critical to have a full overview of the material along with its processing from print to required post-print to be able to finalize the mechanical properties for design use.\nOverview and benefits.\nSLM is a fast developing process that is being implemented in both research and industry. This advancement is very important to both material science and the industry because it can not only create custom properties but it can reduce material usage and give more degrees of freedom with designs that manufacturing techniques can't achieve. Selective laser melting is very useful as a full-time materials and process engineer. Requests such as requiring a quick turnaround in manufacturing material or having specific applications that need complex geometries are common issues that occur in industry. Having SLM would really improve the process of not only getting parts created and sold, but making sure the properties align with whatever is needed out in the field. Current challenges that occur with SLM are having a limit in processable materials, having undeveloped process settings and metallurgical defects such as cracking and porosity. The future challenges are being unable to create fully dense parts due to the processing of aluminum alloys. Aluminum powders are lightweight, have high reflectivity, high thermal conductivity, and low laser absorptivity in the range of wavelengths of the fiber lasers which are used in SLM.\nThese challenges can be improved with doing more research in how the materials interact when being fused together.\nDefect formation.\nDespite the large successes that SLM has provided to additive manufacturing, the process of melting a powdered medium with a concentrated laser yields various microstructural defects through numerous mechanisms that can detrimentally affect the overall functionality and strength of the manufactured part. Although there are many defects that have been researched, we will review some of the major defects that may arise from SLM in this section.\nTwo of the most common mechanical defects include lack of fusion (LOF) or cracking within solidified regions. LOF involves the entrapment of gas within the structure rather than a cohesive solid. These defects can arise from not using a laser source with adequate power or scanning across the powdered surface too quickly, thereby melting the metal insufficiently and preventing a strong bonding environment for solidification. Cracking is another mechanical defect in which low thermal conductivity and high thermal expansion coefficients generate sufficiently high amounts of internal stresses to break bonds within the material, especially along grain boundaries where dislocations are present.\nAdditionally, although SLM solidifies a structure from molten metal, the thermal fluid dynamics of the system often produces inhomogeneous compositions or unintended porosity which can cumulatively affect the overall strength and fatigue life of a printed structure. For example, the directed laser beam can induce convection currents upon direct impact in a narrow \"keyhole\" zone or throughout the semi-molten metal that can impact the material’s overall composition. Similarly, it is found that during solidification, dendritic microstructures progress along temperature gradients at different speeds, thus producing different segregation profiles within the material. Ultimately, these thermal fluid dynamical phenomena generate unwanted inconsistencies within the printed material, and further research into mitigating these effects will continue to be necessary.\nPore formation is a very important defect when samples are printed using SLM. Pores are revealed to form during changes in laser scan velocity due to the rapid formation then collapse of deep keyhole depressions in the surface which traps inert shielding gas in the solidifying metal.\nLastly, secondary effects that arise from the laser beam can unintentionally affect the structure’s properties. One such example is the development of secondary phase precipitates within the bulk structure due to the repetitive heating within solidified lower layers as the laser beam scans across the powder bed. Depending on the composition of the precipitates, this effect can remove important elements from the bulk material or even embrittle the printed structure. Not only that, in powder beds containing oxides, the power of the laser and produced convection currents can vaporize and \"splatter\" oxides at other locations. These oxides accumulate and have a non-wetting behavior, thereby producing a slag that not only removes the beneficial nature of oxide within the composition but also provides a mechanistically favorable microenvironment for material cracking.\nMechanical properties.\nHigh temperature gradients are presented during selective laser melting (SLM) processes, which causes non-equilibrium conditions at the solid/liquid interface, thereby leading to rapid solidification as the melt pool undergoes a phase transformation from liquid to solid. As a consequence, a wide range of effects might take place like the formation of non-equilibrium phases and changes in the microstructure.\nFor the reasons above, the mechanical properties of alloys produced by SLM can deviate substantially from those conventionally manufactured counterparts in their as-built state. A central characteristic of SLM-manufactured alloys is large anisotropy in mechanical properties . While the grain structure in cast metals is typically characterized by roughly uniform, isotropic grains, alloys manufactured using SLM exhibit substantial elongation of grains in the build direction. The anisotropy in grain structure is associated with anisotropy in the distribution of defects, the direction of crack propagation, and ultimately the mechanical properties.\nOn the other hand, because of the special thermo-kinetic features associated with SLM, there are many novel microstructural architectures unique to this process . As a new processing technique, SLM can produce a unique microstructure that is difficult to achieve using conventional techniques.\nNickel-based superalloys.\nEnhancements in creep resistance, ultimate tensile strength and toughness have been reported in nickel alloys. Inconel IN625, a precipitation-hardened nickel-chromium alloy, showed equal or even higher creep strength at elevated temperatures of 650 ̊C and 800 ̊C than wrought IN625. However, SLM-manufactured IN625 exhibited inferior ductility under creep testing conditions. By deploying cyclic heat treatments, both SLM and wrought IN625 obtained some additional strength. The amount of extra strength in the alloys was generally proportional to the matrix volume fraction of γ’’ phase (at 650 ̊C) and δ phase (at 800 ̊C).\nThe fatigue strength and hardness of SLM-manufactured alloys when handling cyclic loads at high temperature, however, tends to be significantly inferior to that of cast or wrought alloys. For another superalloy Inconel IN718, researchers found the additively manufactured material showed large columnar grains with an orientation parallel to the building direction, whereas the wrought material showed a fine-grained structure with no significant texture.\nSLM-based additive manufacturing of nickel superalloys still poses significant challenges due to these alloys’ complex composition. With multiple alloying elements and high aluminum/titanium fraction, these materials, when consolidated through SLM form various secondary phases, which affects the processability and leading to weakness within the structure.\nIron-based alloys (Stainless steels).\nStainless steel grade 316L is an austenitic iron-based alloy that features a low carbon content (ultimate tensile strength (UTS) is also lower for AM specimens since strain hardening is insignificant.\nThe fracture in the SLM-manufactured material is mainly between the grains. The grain boundary damage leads to cracking and subsequently to the failure of the material. The deformation is caused and accelerated by the appearance of precipitates at the grain boundaries. The higher stacking fault energy (SFE) of SLM 316L steel presumably also contributed to its creep behavior.\nApplications.\nThe types of applications most suited to the selective laser melting process are complex geometries and structures with thin walls and hidden voids or channels on the one hand or low lot sizes on the other hand. Advantage can be gained when producing hybrid forms where solid and partially formed or lattice type geometries can be produced together to create a single object, such as a hip stem or acetabular cup or other orthopedic implant where osseointegration is enhanced by the surface geometry. Much of the pioneering work with selective laser melting technologies is on lightweight parts for aerospace where traditional manufacturing constraints, such as tooling and physical access to surfaces for machining, restrict the design of components. SLM allows parts to be built additively to form near net shape components rather than by removing waste material.\nTraditional high-volume manufacturing techniques have a relatively high set-up cost (e.g. Injection moulding, Forging, Investment casting). While SLM currently has a high cost per part owing to its time sensitivity and the overall capital costs of the equipment. However, for limited quantise of bespoke customisable parts, the process remains attractive for a number or uses. This is the case e.g. for spares/replacement parts for obsolete equipment and machines (e.g. vintage cars) or customisable products like implants designed for individual patients .\nTests by NASA's Marshall Space Flight Center, which is experimenting with the technique to make some difficult-to-fabricate parts from nickel alloys for the J-2X and RS-25 rocket engines, show that difficult to make parts made with the technique are somewhat weaker than forged and milled parts but often avoid the need for welds which are weak points.\nThis technology is used to manufacture direct parts for a variety of industries including aerospace, dental, medical and other industries that have small to medium size, highly complex parts and the tooling industry to make direct tooling inserts or those requiring short lead times. The technology is used both for rapid prototyping, as it decreases development time for new products, and production manufacturing as a cost saving method to simplify assemblies and complex geometries. \nThe Northwestern Polytechnical University of China is using a similar system to build structural titanium parts for aircraft. An EADS study shows that use of the process would reduce materials and waste in aerospace applications.\nOn September 5, 2013 Elon Musk tweeted an image of SpaceX's regeneratively-cooled SuperDraco rocket engine chamber emerging from an EOS 3D metal printer, noting that it was composed of the Inconel superalloy. In a surprise move, SpaceX announced in May 2014 that the flight-qualified version of the SuperDraco engine is fully printed, and is the first fully printed rocket engine. Using Inconel, an alloy of nickel and iron, additively-manufactured by direct metal laser sintering, the engine operates at a chamber pressure of at a very high temperature. The engines are contained in a printed protective nacelle, also DMLS-printed, to prevent fault propagation in the event of an engine failure. The engine completed a full qualification test in May 2014, and is slated to make its first orbital spaceflight in April 2018.\nThe ability to 3D print the complex parts was key to achieving the low-mass objective of the engine. According to Elon Musk, \"It’s a very complex engine, and it was very difficult to form all the cooling channels, the injector head, and the throttling mechanism. Being able to print very high strength advanced alloys ... was crucial to being able to create the SuperDraco engine as it is.\"\nThe 3D printing process for the SuperDraco engine dramatically reduces lead-time compared to the traditional cast parts, and \"has superior strength, ductility, and fracture resistance, with a lower variability in materials properties.\"\nAlso in 2018, the FDA approved the first-ever 3D printed spine implant made from titanium using SLM.\nOther applications.\nLaser melting can produce chemical structures (pure metals, their oxides and carbides), and physical structures (homogeneous, alloys, composites, gold-iron, gold-cobalt, gold-nickel alloys).\nPotential.\nSelective laser melting or additive manufacturing, sometimes referred to as rapid manufacturing or rapid prototyping, is in its infancy with relatively few users in comparison to conventional methods such as machining, casting or forging metals, although those that are using the technology have become highly proficient. Like any process or method selective laser melting must be suited to the task at hand. Markets such as aerospace or medical orthopedics have been evaluating the technology as a manufacturing process. Barriers to acceptance are high and compliance issues result in long periods of certification and qualification. This is demonstrated by the lack of fully formed international standards by which to measure the performance of competing systems. The standard in question is ASTM F2792-10 Standard Terminology for Additive Manufacturing Technologies.\nDifference from selective laser sintering (SLS).\nThe use of SLS refers to the process as applied to a variety of materials such as plastics, glass, and ceramics, as well as metals. What sets SLM apart from other 3D printing process is the ability to fully melt the powder, rather than heating it up to a specific point where the powder grains can fuse together, allowing the porosity of the material to be controlled. On the other hand, SLM can go one step further than SLS, by using the laser to fully melt the metal, meaning the powder is not being fused together but actually liquified long enough to melt the powder grains into a homogeneous part. Therefore, SLM can produce stronger parts because of reduced porosity and greater control over crystal structure, which helps prevent part failure. Additionally, certain types of nanoparticles with minimized lattice misfit, similar atomic packing along matched crystallographic planes and thermodynamic stability can be introduced into metal powder to serve as grain refinement nucleates to achieve crack-free, equiaxed, fine-grained microstructures. However, SLM is only feasible when using a single metal powder.\nBenefits.\nSLM has many benefits over traditional manufacturing techniques. The ability to quickly produce a unique part is the most obvious because no special tooling is required and parts can be built in a matter of hours.\nSLM is also one of the few additive manufacturing technologies being used in production. Since the components are built layer by layer, it is possible to design internal features and passages that could not be cast or otherwise machined. Complex geometries and assemblies with multiple components can be simplified to lighter and fewer parts with a more cost-effective assembly. DMLS does not require special tooling like castings, so it is convenient for short production runs.\nEnvironmental impact.\nThere are various components, environments, and material considerations that can affect the environmental impact that the SLM process has. First, the embodied energy that was used to make the printer, which has more than 500 parts, contributes around 124,000 MJ for a standard Renishaw AM250. It is important to note that the most prominent material is steel, which is 100% recyclable. To truly take advantage of the recyclability, a cradle-to-cradle approach can be implemented to ensure that all steel parts are properly discarded of at their end-life through disassembly. The electric use is often the most energy intensive part of the printer, as the high power lasers, chillers, configurations, and part separation all contribute to this. Less volume of parts, more active time, more active idle time (coolers running), and electrical discharge machining (EDM) all increase the energy usage. The higher end of on-site energy during use can be around 640 MJ per part while more efficient use is around 40 MJ per part. In this, a main factor that can be optimized for environmental friendliness is the use of fully renewable energy rather than electric made through gas or coal. Considering now embodied energy of the total lifecycle, at the energy intensive end is less efficient printing processes totaling 2400+ MJ per part while more efficient processes can be as low as 140 MJ per part. Ultimately, the total embodied energy considering all parts made is dependent on many factors but is almost always dominant during the printing phase and more specifically during long idle times and post-processing part removal through EDM. The exception to this is in research environments where the machine is not constantly used and use is more infrequent, in this case, the embodied energy from primary processing and manufacturing is dominant. \nTransportation costs will vary on manufacturing plants and consumers but these values are often negligible (<1%) in comparison to other high impacting parts of the SLM lifecycle. Other factors that are negligible, yet sometimes varied, are: inert gas use, material (powder) waste, materials used, atomization, and disposal of machine components. \nDepending on the part made and its intended use, SLM can help make more lightweight parts with complex dimensions which reduce both energy intensive post-processing machining such as EDM or a computer numerical control (CNC) machining and decrease part weight. Often a direct comparison can only be made by looking at parts made through two different processes. An example is a turbine blade manufactured by investment casting and SLM, where 10853.34 kWh and 10181.57kWh were used to make the same part, respectively. Also conventional manufacturing contributed to 7,325 kgCO2 while AM had 7,027 kgCO2 of emissions. This means that in this specific scenario AM is beneficial by 4%, which could be significant over the 25,578 aircraft worldwide. Another example is the 1kg weight reduction through a hydraulic valve body which estimates a saving of 24,500L of jet fuel and 63 tons of CO2 emissions from a lightweight design and decreased material used compared to traditional manufacturing methods. SLM is often a more sustainable option due to decreased raw material use, less complex tool use, lightweight part potential, near-perfect final geometries, and on-demand manufacturing.\nConstraints.\nThe aspects of size, feature details and surface finish, as well as print through dimensional error in the Z axis may be factors that should be considered prior to the use of the technology. However, by planning the build in the machine where most features are built in the x and y axis as the material is laid down, the feature tolerances can be managed well. Surfaces usually have to be polished to achieve mirror or extremely smooth finishes.\nFor production tooling, material density of a finished part or insert should be addressed prior to use. For example, in injection molding inserts, any surface imperfections will cause imperfections in the plastic part, and the inserts will have to mate with the base of the mold with temperature and surfaces to prevent problems.\nIndependent of the material system used, the SLM process leaves a grainy surface finish due to \"powder particle size, layer-wise building sequence and [the spreading of the metal powder prior to sintering by the powder distribution mechanism].\"\nMetallic support structure removal and post processing of the part generated may be a time-consuming process and require the use of machining, EDM and/or grinding machines having the same level of accuracy provided by the RP machine.\nLaser polishing by means of shallow surface melting of SLM produced parts is able to reduce surface roughness by use of a fast-moving laser beam providing \"just enough heat energy to cause melting of the surface peaks. The molten mass then flows into the surface valleys by surface tension, gravity and laser pressure, thus diminishing the roughness.\"\nWhen using rapid prototyping machines, files, which do not include anything but raw mesh data in binary (generated from Solid Works, CATIA, or other major CAD programs) need further conversion to and files (the format required for non-stereolithography machines). Software converts file to files, as with the rest of the process, there can be costs associated with this step.\nMachine components.\nThe typical components of a SLM machine include: laser source, roller, platform piston, removable build plate, supply powder, supply doses (e.g. piston), and optics and mirrors. The typical build envelope across most platforms are (e.g., for EOS M 290) of 250 x 250 x 325 mm, and the ability to 'grow' multiple parts at one time,", "Engineering,_Manufacturing": 1.0000032187, "qwen": "Yes"}
{"id": "53366761", "revid": "9676078", "url": "https://en.wikipedia.org/wiki?curid=53366761", "title": "Liuyang High-Tech Industrial Development Zone", "text": "Liuyang High-Tech Industrial Development Zone  is a Hi-tech Industrial Development Zone at province level in Liuyang City, Hunan Province, China. It is the 2nd largest industrial zone of Liuyang by economic volume, after the Liuyang Economic and Technological Development Zone. The industrial zone is the original Liuyang Manufacturing industrial Base  created in 2003, it was Changed to the present name on 14 July 2016. The industrial zone centers in Yong'an Town of Liuyang, it covers an area of . As of 2015, its gross output value of industries is CNY 30.31 billion (US$4.87 billion), the financial revenue reaches 1.01 billion yuan (US$0.16 billion).", "Engineering,_Manufacturing": 1.0000013113, "qwen": "Yes"}
{"id": "53368649", "revid": "44780934", "url": "https://en.wikipedia.org/wiki?curid=53368649", "title": "2017 Copa do Brasil Third Round", "text": "The 2017 Copa do Brasil Third Round was played from 8 March to 5 April 2017, to decide the 10 teams advancing to the Fourth Round. In this year, each tie was played on a home-and-away two-legged basis. If tied on aggregate, the away goals rule would be used. If still tied, extra time would not be played, and the penalty shoot-out would be used to determine the winner. Hosting was determined by a draw.\nMatches.\n\nMatch 61.\n\"Sport won 4–0 on aggregate and advanced to the fourth round.\"\nMatch 62.\n\"Joinville won 3–2 on aggregate and advanced to the fourth round.\"\nMatch 63.\n\"Cruzeiro won 5–0 on aggregate and advanced to the fourth round.\"\nMatch 64.\n\"Fluminense won 4–3 on aggregate and advanced to the fourth round.\"\nMatch 65.\n\"Internacional won 7–1 on aggregate and advanced to the fourth round.\"\nMatch 66.\n\"Corinthians won 3–1 on aggregate and advanced to the fourth round.\"\nMatch 67.\n\"Goiás won 5–1 on aggregate and advanced to the fourth round.\"\nMatch 68.\n\"Vitória won 2–1 on aggregate and advanced to the fourth round.\"\nMatch 69.\n\"Tied 0–0 on aggregate, Paraná won on penalties and advanced to the fourth round.\"\nMatch 70.\n\"São Paulo won 4–2 on aggregate and advanced to the fourth round.\"", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "61746556", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=61746556", "title": "Kamalini Ramdas", "text": "Kamalini Ramdas is a Professor of Management Science and Operations and Deloitte Chair in Innovation & Entrepreneurship at London Business School, with expertise in the areas of innovation, entrepreneurship, and operations management. Ramdas' research examines innovative approaches, including service innovation, operational innovation, and business model innovation, to accelerate value creation in various service and manufacturing industries.\nCareer.\nKamalini Ramdas earned her BS in mathematics from St. Stephen's College, Delhi University in 1986, M.S. in operations research from University of Delaware in 1989, and PhD in operations management from the Wharton School of University of Pennsylvania in 1995. Prior to joining London Business School in 2008, Ramdas served as Associate Professor of Business Administration at University of Virginia Darden School of Business. She was also on the faculty of McCombs School of Business of The University of Texas at Austin.\nAt London Business School, Ramdas is a Professor of Management Science and Operations and Deloitte Chair in Innovation & Entrepreneurship. She also serves as the Subject Area Chair of Management Science & Operations.\nBetween 2019 and 2020, she served as President of the Manufacturing and Service Operations Management Society (MSOM), one of the largest societies of the Institute for Operations Research and the Management Sciences (INFORMS).\nAcademic work.\nRamdas is known for her work in innovation, entrepreneurship, and operations management. Her work has found applications in a wide range of industries, including healthcare, telecommunication, consumer packaged goods, and assembled products.\nIn particular, she is a pioneering scholar in innovation in healthcare delivery, known internationally for her work in shared medical appointments. In 2011, she was invited to present her work on innovation in healthcare delivery at the World Economic Forum in Davos.\nShe serves or has served on the editorial board of major operations management journals, including \"Management Science\", \"Manufacturing & Service Operations Management\", \"IEEE Transactions on Engineering Management\", and \"Productions and Operations Management\".\nPublications.\nAccording to Google Scholar, Ramdas' 10 most widely cited papers are:", "Engineering,_Manufacturing": 0.996507585, "qwen": "Yes"}
{"id": "1903362", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1903362", "title": "Maskless lithography", "text": "Maskless lithography (MPL) is a photomask-less photolithography-like technology used to project or focal-spot write the image pattern onto a chemical resist-coated substrate (e.g. wafer) by means of UV radiation or electron beam.\nIn microlithography, typically UV radiation casts an image of a time constant mask onto a photosensitive emulsion (or photoresist).\nTraditionally, mask aligners, steppers, scanners, and other kinds of non-optical techniques are used for high speed microfabrication of microstructures, but in case of MPL, some of these become redundant.\nMaskless lithography has two approaches to project a pattern: rasterized and vectorized. In the first one it utilizes generation of a time-variant intermittent image on an electronically modifiable (virtual) mask that is projected with known means (also known as Laser Direct Imaging and other synonyms). In the vectored approach, direct writing is achieved by radiation that is focused to a narrow beam that is scanned in vector form across the resist. The beam is then used to directly write the image into the photoresist, one or more pixels at a time. Also combinations of the two approaches are known, and it is not limited to optical radiation, but also extends into the UV, includes electron-beams and also mechanical or thermal ablation via MEMS devices.\nAdvantages.\nThe MPL advantage is a high speed parallel manipulation of the pattern enabled by a large and cheap available computing capacity, which is not an issue with the standard approach that decouples to a slow, but precise structuring process for writing a mask from a fast and highly parallel copy process to achieve high replication throughputs as demanded by industry.\nA key advantage of maskless lithography is the ability to change lithography patterns from one run to the next, without incurring the cost of generating a new photomask. This may prove useful for double patterning or compensation of non-linear material behavior (e.g. when utilizing cheaper, non-crystalline substrate or to compensate for random placement errors of preceding structures).\nDisadvantages.\nThe main disadvantages are complexity and costs for the replication process, the limitation of rasterization in respect to oversampling causes aliasing artefact, especially with smaller structures (which may affect yield), while direct vector writing is limited in throughput. Also the digital throughput of such systems forms a bottleneck for high resolutions, i.e. structuring a 300mm diameter wafer with its area of ~707cm² requires about 10 TiB of data in a rasterized format without oversampling and thus suffers from step-artefacts (aliasing). Oversampling by a factor of 10 to reduce these artefacts adds another two orders of magnitude 1 PiB per single wafer that has to be transferred in ~1 min to the substrate to achieve high volume manufacturing speeds.\nIndustrial maskless lithography is therefore currently only widely found for structuring lower resolution substrates, like in PCB-panel production, where resolutions ~50µm are most common (at ~2000 times lower throughput demand on the components).\nForms.\nCurrently, the main forms of maskless lithography are electron beam and optical. In addition, focused ion beam (FIB) systems have established an important niche role in failure analysis and defect repair. Also, systems based on arrays of mechanical and thermally ablative probe tips have been demonstrated.\nElectron beam (e-beam).\nThe most commonly used form of maskless lithography today is electron beam lithography. Its widespread use is due to the wide range of electron beam systems available accessing an equally wide range of electron beam energies (~10 eV to ~100 keV). This is already being used in wafer-level production at eASIC, which uses conventional direct-write electron beam lithography to customize a single via layer for low-cost production of ASICs.\nMost maskless lithography systems currently being developed are based on the use of multiple electron beams. The goal is to use the parallel scanning of the beams to speed up the patterning of large areas. However, a fundamental consideration here is to what degree electrons from neighboring beams can disturb one another (from Coulomb repulsion). Since the electrons in parallel beams are traveling equally fast, they will persistently repel one another, while the electron lenses act over only a portion of the electrons' trajectories.\nOptical.\nDirect laser writing is a very popular form of optical maskless lithography, which offers flexibility, ease of use, and cost effectiveness in R&D processing (small batch production). The underlying technology uses spatial light modulating (SLM) micro-arrays based on glass to block laser pathway from reaching a substrate with a photoresist (in similar manner to digital micromirror devices). This equipment offers rapid patterning at sub-micrometer resolutions, and offers a compromise between performance and cost when working with feature sizes of approximately 200 nm or greater. Direct laser writing for microelectronics packaging, 3D electronics and heterogeneous integration were developed in 1995 at the Microelectronics and Computer Technology Corporation (or MCC) in Austin, Texas. The MCC system was fully integrated with precision control for 3D surfaces and artificial intelligence software with real-time machine learning and included laser wavelengths for standard i-line resist and DUV 248nm. The MCC system also included circuit editing capabilities for isolating circuits on a programmable wafer design. In 1999, the MCC system was advanced for use in MEMS manufacturing. \nInterference lithography or holographic exposures are not maskless processes and therefore do not count as \"maskless\", although they have no 1:1 imaging system in between.\nPlasmonic direct writing lithography uses localized surface plasmon excitations via scanning probes to directly expose the photoresist.\nFor improved image resolution, ultraviolet light, which has a shorter wavelength than visible light, is used to achieve resolution down to around 100 nm. The main optical maskless lithography systems in use today are the ones developed for generating photomasks for the semiconductor and LCD industries.\nIn 2013, a group at Swinburne University of Technology published their achievement of 9 nm feature size and 52 nm pitch, using a combination of two optical beams of different wavelengths.\nDLP technology can also be used for maskless lithography.\nFocused ion beam.\nFocused ion beam systems are commonly used today for sputtering away defects or uncovering buried features. The use of ion sputtering must take into account the redeposition of sputtered material.\nProbe-tip contact.\nIBM Research has developed an alternative maskless lithography technique based on atomic force microscopy. In addition, Dip Pen Nanolithography is a promising new approach for patterning submicrometer features.\nResearch.\n2000s.\nTechnologies that enable maskless lithography is already used for the production of photomasks and in limited wafer-level production. There are some obstacles ahead of its use in high-volume manufacturing. First, there is a wide diversity of maskless techniques. Even within the electron-beam category, there are several vendors (Multibeam, Mapper Lithography, Canon, Advantest, Nuflare, JEOL) with entirely different architectures and beam energies. Second, throughput targets exceeding 10 wafers per hour still need to be met. Third, the capacity and ability to handle the large data volume (Tb-scale) needs to be developed and demonstrated.\nIn recent years DARPA and NIST have reduced support for maskless lithography in the U.S.\nThere was a European program that would push the insertion of maskless lithography for IC manufacturing at the 32-nm \"half-pitch\" node in 2009. Project name was MAGIC, or \"MAskless lithoGraphy for IC manufacturing\", in frame of EC 7th Framework Programme (FP7).\nDue to the increased mask costs for multiple patterning, maskless lithography is once again prompts relevant research in this field.\nDARPA (United States).\nSince at least 2001 DARPA has invested in a variety of maskless patterning technologies including parallel e-beam arrays, parallel scanning probe arrays, and an innovative e-beam lithography tool to enable low-volume manufacturing process. The technology is codenamed as Gratings of Regular Arrays and Trim Exposures (GRATE) (previously known as Cost Effective Low Volume Nanofabrication).\nEconomics.\nFoundries.\nIn 2018 the Dutch and Russia jointly funded (Rusnano) company Mapper Lithography producing multi e-beam maskless lithography MEMS components went bankrupt and was acquired by ASML Holding, a major competitor at the time. The foundry producing devices is located near Moscow, Russia. As of early 2019 it was run by Mapper LLC. The Mapper Lithography originally was created at Delft University of Technology in 2000.", "Engineering,_Manufacturing": 0.9999696016, "qwen": "Yes"}
{"id": "1906087", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1906087", "title": "Bharathidasan University", "text": "Bharathidasan University (BDU) is a university in the city of Tiruchirappalli, Tamil Nadu, India. It is located on Tiruchirappalli-Pudukkottai National Highway 336. It has affiliated colleges in the districts of Ariyalur district, Karur, Nagapattinam, Perambalur, Pudukkottai, Thanjavur, Tiruvarur and Tiruchirapalli. It is a recognised university, supported by the University Grants Commission of India. All major faculties of science and arts are represented. The university has totally 4 Faculties, 16 Schools, 37 Departments and 29 Specialized Research Centres.\nThe University Departments/Schools are offering 151 programmes including 40 PG programmes in M.A., M.Sc. and M.Tech. The above programmes are conducted under the Choice Based Credit System (CBCS) in Semesters: 31 M.Phil., 33 Ph.D., 19 P.G. Diploma, 11 Diploma and 10 Certificates. In addition to the regular teaching programmes in the Departments and Schools, the university under its Distance Education mode is conducting 15 UG and 26 PG programmes. All the UG and PG programmes are conducted under non-semester system and MCA and MBA programmes are conducted under semester system along with the regular programmes. The MCA and MBA programmes conducted under this mode are very popular.\nFaculties and schools.\nThe university has the following faculties and schools:\nAffiliated colleges.\nAutonomous arts and science colleges.\n1. Government Arts College (Autonomous), Karur - 639 005.\n2. Government College (Autonomous), Kumbakonam - 612 001.\n3. H.H. The Rajah's College (Autonomous), Pudukkottai - 622 001.\n4. Rajah Serfoji Government College, (Autonomous) Thanjavur - 613 005.\n5. Thanthai Periyar Government Arts and Science College (Autonomous), Tiruchirappalli - 620 023.\n6. Government College for Women (Autonomous), Kumbakonam - 612 001.\n7. K. N. Government College for Women (Autonomous) Thanjavur - 613 007.\n8. Kaalaignar Karunanidhi Government Arts College for Women, (Autonomous)\nPudukkottai - 622 001.\n9. A.V.V.M. Sri Pushpam College (Autonomous), Poondi - 613 503.\n10. Bishop Heber College, (Autonomous) Tiruchirappalli - 620 017\n11. Jamal Mohamed College, (Autonomous) Tiruchirappalli - 620 020.\n12. National College (Autonomous), Tiruchirappalli - 620 001\n13. Nehru Memorial College, (Autonomous) Puthanampatti - 621 007.\n14. St. Joseph's College (Autonomous), Tiruchirappalli - 620 002.\n15. A.D.M. College for Women, (Autonomous) Nagapattinam - 611 001.\n16. Holy Cross College (Autonomous), Tiruchirappalli - 620 002.\n17. Seethalakshmi Ramaswami College, (Autonomous) Tiruchirappalli - 620 002.\n18. Edayathangudi G.S. Pillai Arts & Science College, Nagapattinam - 611 001.\n19. J.J. College of Arts & Science(Autonomous), Namanasamuthiram, Pudukkottai - 622 404\n20. Srimad Andavan Arts & Science College, Thiruvanaikoil, Tiruchirappalli - 620 005.\n21. Thanthai Hans Roever College, Perambalur - 621 212.\n22. Cauvery College for Women (Autonomous), Annamalai Nagar, Tiruchirappalli - 620 018\n23. Dhanalakshmi Srinivasan College of Arts & Science for Women, Perambalur - 621 212\n24. Sengamala Thayaar Educational Trust Women's College, Mannargudi - 614 001\nNon-autonomous arts and science colleges.\n1. A.A. Government Arts College, Musiri - 621 201.\n2. Dr. Kalaignar Government Arts College, Kulithalai (Sattamandra Ponvizha), Ayyar Malai, Kulithalai, Karur - 639 120\n3. Dr. Puratchi Thalaivar M.G.R.Govt. Arts & Science College, (Boys Higher Secondary School) Kudavasal 612 601, Thiruvarur District\n4. Government Arts & Science College(Co-Education), Veppanthattai, Perambalur.\n5. Government Arts and Science College, Community Hall, Amman Nagar, Aravakurichi TK, Karur Dt - 639201.\n6. Government Arts and Science College, Govt. Boys Higher Secondary School Campus, Thirumayam TK - Pudukottai Dt - 622507.\n7. Government Arts and Science College, Old Block Development Office, Poothalur, Thanjavur Dt. - 613 102.\n8. Government Arts and Science college, Govt. Polytechnic campus, Aranthangi - 614 616.\n9. Government Arts and Science College, Jayankondam, Ariyalur Dt. - 621 802.\n10. Government Arts and Science College, Kadambadi Main Road, Opp. ADJ Dharamambal Polytechnic, Nagappattinam - 611 001.\n11. Government Arts and Science College, Karambakudi, Pudukkottai District\n12. Government Arts and Science College, Lalgudi - 621 601\n13. Government Arts and Science College, Perambalur -621 107.\n14. Government Arts and Science College, Peravurani, Thanjavur District\n15. Government Arts and Science College, Punchayat Union Model Primary School, Pannankombu, Manapparai TK, Tiruchirappalli 621306\n16. Government Arts and Science College, Regional ITI Campus, Kalaignar Nagar, Alangudi TK - Pudukottai - 622301\n17. Government Arts and Science College, Tharagampatti, Karur (Dt.)\n18. Government Arts College, Ariyalur - 621 713.\n19. Government Arts College, Tiruchirappalli - 620 022\n20. Government College of Arts and Science, Govt. Boys Higher Secondary School Campus, South Street, Nannilam - Thiurvarur (Dt.) 610 105.\n21. Government College of Arts and Science, Opp. To Kasturibai Gandhi Kanniya Gurukulam, Nagai Road, Vedaranyam - 614 810.\n22. Government College of Arts and Science, Govt. Higher Secondary School Campus, Inamkulathur - 621 203\n23. Government College of Arts and Science, Thandalaichery, Velur Post,\nThiruthuraipoondi- 614 715, Thiruvarur (Dt.)\n24. M.R. Government Arts College, Mannargudi - 614 001.\n25. Thiru. Vi. Ka. Government Arts College, Thiruvarur - 610 003.\n26. Government Arts and Science College (Women), Orathanad - 614 625\n27. Government Arts and Science College for Women, Jamiya Elementary School Campus, Jinnah Street, Koothanallur, Tiruvarur Dt. - 614101\n28. Government Arts and Science College for Women, Veppur, Perambalur District\n29. Ganesar Senthamil College of Arts and Science, Melaisivapuri - 622 403.\n30. Khadir Mohideen College, Adirampattinam - 614 701\n31. Rajah's College, Thiruvaiyaru - 613 204.\n32. S.K.S.S. Arts College, Thiruppanandal - 612 504.\n33. Tamilavel Umamaheswaranar Karanthai Arts College, Thanjavur - 613 002.\n34. Urumu Dhanalakshmi College, Tiruchirappalli - 620 019.\n35. Aadhavan Arts and Science College, Alathur Village Chettiyappatti Panchayat, Manapparai T.K., Tiruchirappalli-621 306\n36. ABI & ABI College, Vayalur, Thanjavur - 613 003.\n37. Adaikala Matha College, Arun Nagar, Vallam, Thanjavur - 613 403.\n38. Annai College of Arts & Science, Kumbakonam-612 503.\n39. Annai Vailankanni Arts & Science College, V.O.C. Nagar Thanjavur 613 007\n40. Arputha College of Arts & Science, Arputha Nagar, Vamban - 622 303\n41. Arungarai Amman College of Arts & Science, Karur District - 639 202\n42. Bharath College of Science & Management, South Garden, Thanjavur - 613 007.\n43. Cambridge College of Arts and Science, Vettamangalam, Karur District - 639 117\n44. Care College of Arts & Science, No.27, Thayanur Village, Trichy 620 009\n45. Christhu Raj College, Panjapur, Edamalaipatti Pudur, Tiruchirappalli - 620 012\n46. CSI - Bishop Solomon Doraisawmy College of Arts and Science, Karur - 639001\n47. Dharmambal Ramasamy Arts & Science College, Orathanadu T.k.Thanjavur - 614 625.\n48. Dr. Nallikuppusamy Arts College, Manakkarambai, Thanjavur - 613 003.\n49. Elizabeth College of Arts and Science, Annamangalam(P.O), Vepanthattai T.K, Perambalur - 620 102\n50. Enathi Rajappa College of Arts & Science, Enathi Post, Pattukkottai - 614 615\n51. Imayam College of Arts & Science, Thuraiyur- 621 206\n52. Indra Ganesan College of Arts & Science, Madurai Main Road, Manikandam Post, Tiruchirappalli 620 012\n53. Jairams Arts and Science College NH-7 Salem Bye-Pass Road, (Near) Mahamariamman Temple Karur -639 002.\n54. Jesu Arts and Science College (Co-Educational), Alangudi, Pudukkottai Dist. -622 301.\n55. Kokila Arts & Science College (Co-education), Viralimalai, Manaparai Road, Pudukkottai\n56. Kongu College of Arts & Science, Deeran Chinnamalai Nagar, Karur - 639 006.\n57. Krishna College of Arts and Science, UGR Nagar, Kolluthannipatty, Melapaguthi Village, Kadavur (Tk), Karur (Dt.) -621 301\n58. Kurinji College of Arts & Science, Green Ways Road, Tiruchirappalli - 620 002.\n59. M.I.E.T. Arts & Science College, Gundur, Tiruchirappalli - 620 007.\n60. Mahatma Arts and Science College, Ariyur Village, Illuppur Taluk, Pudukkottai District- 622 101\n61. Maruthu Pandiyar College, Vallam (P.O.), Thanjavur - 613 403\n62. MASS College of Arts and Science, Kumbakonam - 612 501\n63. Meenakshi Chandrasekaran College of Arts & Science, Pattukkottai - 614 626\n64. Meenakshi Ramasamy Arts and Science College, Udaiyarpalayam, Ariyalur-.621 804.\n65. Modern Arts and Science College, 35A, Sannathi Street, Jayankondam, - 621 802\n66. Mother Terasa College of Arts and Science, Mettusalai, Veerappatti Village, Illupur (PO), Pudukkottai Dt. - 622 102\n67. Naina Mohamed College of Arts & Science, Rajendrapuram, Pudukkottai - 614 624\n68. National Arts and Science College TrichyRoad, Jayankondam Ariyalur Dt. 621 802\n69. Navalar Na. Mu. Venkatasamy Nattar Thiruvarul Kallori, Kabilar Nagar, Vennatrankarai, Thanjavur - 613 003.\n70. Nethaji Subash Chandra Bose College, Thiruvarur - 614 001\n71. Paventhar Bharathidasan College of Arts & Science, Pudukkottai - 622 515.\n72. Rajagiri Dawood Batcha College of Arts & Science, Papanasam, Thanjavur - 614 207\n73. S.K. Arts & Science College Thamaraipulam, Vedaranyam 614 809\n74. S.K. College of Arts and Science, Melavasal, Mannargudi, Thiruvarur District- 614 014.\n75. S.R.V. College of Arts & Science, Pirattiyur, Tiruchirappalli - 620 009\n76. Sembodai R.V. Arts & Science College, Vedaraniyam T.K., Nagapattinam-614 809\n77. Sir Issac Newton Arts and Science College, Pappakoil Village, Anthanapettai (PO),Nagappatinam Dt. - 611 001\n78. Sri Amaraavathi College of Arts and Science, Velliannai, Karur - 639 908\n79. Sri Meenakshi Vidiyal College of Arts & Science, Valanadu Kaikatty, Marungapuri Tk, Tiruchirappalli Dt. 621 305\n80. Sri Sankara Arts and Science College, Asur, Kumbakonam, 612 501\n81. Sri Venkateshwara College of Arts & Science, Peravurani - 614 804.\n82. Srinivasan College of Arts and Science, Perambalur -621 212\n83. SRM Trichy Arts & Science College, Irungalur Village, Mannachanallur TK, Tiruchirappalli - 621 105\n84. St. Peter's Arts and Science College, Melaneduvai Post, Adimadam, Udayarpalayam Tk, Ariyalur (Dt) - 621 801\n85. Sudharsan College of Arts Science, Perumanadu Villages, Iluppur Taluk, Pudukkottai Dt\n86. Swami Dayananda College of Arts & Science, Tiruvarur - 612 610\n87. Swami Vivekananda Arts & Science College, Sami Arul Nagar, Vallam, Thanjavur - 613 007\n88. Vailankanni Matha Arts and Science College, ECR Main Road, Prathabaramapuram, Keelvelur TK, Nagapattinam 611 111.\n89. Valluvar College of Science and Management, Kodaiyur, Aravakurichi Taluk, Karur - 639 003\n90. Vikas College of Arts & Science, Inamkulathur, Srirangam TK, Tiruchirappalli 621 303.\n91. ABC College of Arts and Science for Women, Erichy, Chithamaraviduthi Po, Aranthangi (Tk), Pudukkottai 614 622.\n92. Aiman College of Arts & Science for Women, K. Sathanur, Tiruchirappalli - 620 021.\n93. Annai Ayesha Arts & Science College for Women, College Main Raod, Valikandapuram, Perambalur Dt 621 115.\n94. Annai Khadeeja Arts and Science College for Women, Kandanivayal Village, Edayathimangalam Po., Manamelkudi Tk., Pudukkottai (Dt.) - 6214620.\n95. Annai Women's College, Aurobindo Nagar, Vennaimalai, Karur 639 006.\n96. Arasu College of Arts & Science for Women, Panduthakaran Pudhur, Punjai Kadambankurichy Village, Manmangalam TK, Karur Dt. - 639006.\n97. Auxilium College of Arts and Science for Women, Regunathapuram Village, Alangudi Taluk, Pudukottai Dt - 622 302\n98. Bharathi Vidyalaya College of Arts & Science (Women), Trichy Road,\nThirugokaranam(PO), Pudukkottai - 622002\n99. Bon Secours Arts and Science College for Women, Ruckmanipalayam, Mannargudi 614 001, Thiruvarur Dt.\n100. Bon Secours College for Women, Vilar Bye pass Road, Thanjavur - 613 006.\n101. Chidambaram Pillai College for Women, Manachanallur, Tiruchirappalli - 621 005.\n102. Dr. M. Sivakannu Women's Arts & Science College, Ayakkaranpulam, Vedaranyam (Tk) Nagapattinam Dt. 614 707\n103. Idhaya College of Women, Sakkottai, Kumbakonam 612 001.\n104. Karur Velalar college of Arts Science for Women, SF.No. 14/3, Kuppam Village, Karur- Erode Main Road, Kuppam (PO), Aravakurichi Tk., Karur Dt. 639 111.\n105. M.I.T. College of Arts & Science for Women, Annai Nagar, Musiri TK, Tiruchirappalli Dt. - 621 211.\n106. Meera College of Arts and Science for Women, Thanjavur Main Road, Keelapalur Post, Ariyalur - 621707\n107. Mother Gnanamma Women's College of Arts and Science, Varadarajanpet,\nJayankondam Taluk, Ariyalur District - 621 805.\n108. Queens College of Arts & Science for Women, Punal Kulam, Kandarvakottai, Pudukkottai - 613 303\n109. Rabiammal Ahamed Maideen College for Women, Thiruvarur - 610 002.\n110. S.M.K. College of Arts and Science for Women, Kilakuvadi, Thuraiyur, Tiruchirappalli Dt.\n111. Servite Arts and Science College for Women, T.Iadaiayapatti, Kalladai Village, Thogaimalai Panchayat, Karur - 621 313\n112. Shrimati Indira Gandhi College, Tiruchirappalli - 620 002.\n113. Sri Bharathi Arts and Science College for Women, Pudukkottai 622 303\n114. Sri Sarada Niketan College of Science for Women, Karur - 639 005.\n115. Sri Saradha College for Women, Perambalur - 621 212.\n116. Subashakthi College of Arts and Science for Women, Sathiyamangalam Post, Kulithalai T.K., Karur Dt. - 639 120\n117. Sulthana Abdullah Rowther College for Women, Thiruvarur - 614 101\n118. Uswathun Hasana Mamaji Haji Abdul Latheef Women's College, Pallapatti, Karur - 639 205\n119. Vinayaga College of Arts and Science for Women, Karuppur, Keelapaluvur, Ariyalur Dt-621 707\nRankings.\nThe National Institutional Ranking Framework (NIRF) ranked Bharathidasan University 77th overall in India and 53rd among universities in 2020.", "Engineering,_Manufacturing": 0.9998607635, "qwen": "Yes"}
{"id": "304604", "revid": "222130", "url": "https://en.wikipedia.org/wiki?curid=304604", "title": "Mechatronics", "text": "Mechatronics engineering also called mechatronics, is an interdisciplinary branch of engineering that focuses on the integration of mechanical, electrical and electronic engineering systems, and also includes a combination of robotics, electronics, computer science, telecommunications, systems, control, and product engineering.\nAs technology advances over time, various subfields of engineering have succeeded in both adapting and multiplying. The intention of mechatronics is to produce a design solution that unifies each of these various subfields. Originally, the field of mechatronics was intended to be nothing more than a combination of mechanics, electrical and electronics, hence the name being a portmanteau of the words \"mechanics\" and \"electronics\"; however, as the complexity of technical systems continued to evolve, the definition had been broadened to include more technical areas.\nThe word \"mechatronics\" originated in Japanese-English and was created by Tetsuro Mori, an engineer of Yaskawa Electric Corporation. The word \"mechatronics\" was registered as trademark by the company in Japan with the registration number of \"46-32714\" in 1971. The company later released the right to use the word to the public, and the word began being used globally. Currently the word is translated into many languages and is considered an essential term for advanced automated industry.\nMany people treat \"mechatronics\" as a modern buzzword synonymous with automation, robotics and electromechanical engineering.\nFrench standard NF E 01-010 gives the following definition: \"approach aiming at the synergistic integration of mechanics, electronics, control theory, and computer science within product design and manufacturing, in order to improve and/or optimize its functionality\".\nHistory.\nThe word \"mechatronics\" was registered as trademark by the company in Japan with the registration number of \"46-32714\" in 1971. The company later released the right to use the word to the public, and the word began being used globally.\nWith the advent of information technology in the 1980s, microprocessors were introduced into mechanical systems, improving performance significantly. By the 1990s, advances in computational intelligence were applied to mechatronics in ways that revolutionized the field.\nDescription.\nA mechatronics engineer unites the principles of mechanics, electrical, electronics, and computing to generate a simpler, more economical and reliable system.\nEngineering cybernetics deals with the question of control engineering of mechatronic systems. It is used to control or regulate such a system (see control theory). Through collaboration, the mechatronic modules perform the production goals and inherit flexible and agile manufacturing properties in the production scheme. Modern production equipment consists of mechatronic modules that are integrated according to a control architecture. The most known architectures involve hierarchy, polyarchy, heterarchy, and hybrid. The methods for achieving a technical effect are described by control algorithms, which might or might not utilize formal methods in their design. Hybrid systems important to mechatronics include production systems, synergy drives,\nexploration rovers, automotive subsystems such as anti-lock braking systems and spin-assist, and everyday equipment such as autofocus cameras, video, hard disks, CD players and phones.\nCourse structure.\nMechatronics students take courses in various fields:\nApplications.\nPhysical implementations.\nMechanical modeling calls for modeling and simulating physical complex phenomena in the scope of a multi-scale and multi-physical approach. This implies to implement and to manage modeling and optimization methods and tools, which are integrated in a systemic approach.\nThe specialty is aimed for students in mechanics who want to open their mind to systems engineering, and able to integrate different physics or technologies, as well as students in mechatronics who want to increase their knowledge in optimization and multidisciplinary simulation techniques.\nThe specialty educates students in robust and/or optimized conception methods for structures or many technological systems, and to the main modeling and simulation tools used in R&D. Special courses are also proposed for original applications (multi-materials composites, innovating transducers and actuators, integrated systems, …) to prepare the students to the coming breakthrough in the domains covering the materials and the systems.\nFor some mechatronic systems, the main issue is no longer how to implement a control system, but how to implement actuators. Within the mechatronic field, mainly two technologies are used to produce movement/motion.\nSubdisciplines.\nMechanical.\nMechanical engineering is an important part of mechatronics engineering. It includes the study of mechanical nature of how an object works. Mechanical elements refer to mechanical structure, mechanism, thermo-fluid, and hydraulic aspects of a mechatronics system. The study of thermodynamics, dynamics, fluid mechanics, pneumatics and hydraulics. Mechatronics engineer who works a mechanical engineer can specialize in hydraulics and pneumatics systems, where they can be found working in automobile industries. A mechatronics engineer can also design a vehicle since they have strong mechanical and electronical background. Knowledge of software applications such as computer-aided design and computer aided manufacturing is essential for designing products. Mechatronics covers a part of mechanical syllabus which is widely applied in automobile industry.\nMechatronic systems represent a large part of the functions of an automobile. The control loop formed by sensor—information processing—actuator—mechanical (physical) change is found in many systems. The system size can be very different. The Anti-lock braking system (ABS) is a mechatronic system. The brake itself is also one. And the control loop formed by driving control (for example cruise control), engine, vehicle driving speed in the real world and speed measurement is a mechatronic system, too. The great importance of mechatronics for automotive engineering is also evident from the fact that vehicle manufacturers often have development departments with \"Mechatronics\" in their names.\nElectronics and Electricals.\nElectronics and Telecommunication engineering specializes in electronics devices and telecom devices of a mechatronics system. A mechatronics engineer specialized in electronics and telecommunications have knowledge of computer hardware devices. The transmission of signal is the main application of this subfield of mechatronics. Where digital and analog systems also forms an important part of mechatronics systems. Telecommunications engineering deals with the transmission of information across a medium.\nElectronics engineering is related to computer engineering and electrical engineering. Control engineering has a wide range of electronic applications from the flight and propulsion systems of commercial airplanes to the cruise control present in many modern cars. VLSI designing is important for creating integrated circuits. Mechatronics engineers have deep knowledge of microprocessors, microcontrollers, microchips and semiconductors. The application of mechatronics in electronics manufacturing industry can conduct research and development on consumer electronic devices such as mobile phones, computers, cameras etc. For mechatronics engineers it is necessary to learn operating computer applications such as MATLAB and Simulink for designing and developing electronic products.\nMechatronics engineering is a interdisciplinary course, it includes concepts of both electrical and mechanical systems. A mechatronics engineer engages in designing high power transformers or radio-frequency module transmitters.\nAvionics.\nAvionics is also considered a variant of mechatronics as it combines several fields such as electronics and telecom with Aerospace engineering. It is the subdiscipline of mechatronics engineering and aerospace engineering which is engineering branch focusing on electronics systems of aircraft. The word avionics is a blend of aviation and electronics. The electronics system of aircraft includes aircraft communication addressing and reporting system, air navigation, aircraft flight control system, aircraft collision avoidance systems, flight recorder, weather radar and lightning detector. These can be as simple as a searchlight for a police helicopter or as complicated as the tactical system for an airborne early warning platform.\nAdvanced Mechatronics.\nAnother variant is Motion control for Advanced Mechatronics, presently recognized as a key technology in mechatronics. The robustness of motion control will be represented as a function of stiffness and a basis for practical realization. Target of motion is parameterized by control stiffness which could be variable according to the task reference. The system robustness of motion always requires very high stiffness in the controller.\nIndustrial.\nThe branch of industrial engineer includes the design of machinery, assembly and process lines of various manufacturing industries. This branch can be said somewhat similar to automation and robotics. Mechatronics engineers who works as industrial engineers design and develop infrastructure of a manufacturing plant. Also it can be said that they are architect of machines. One can work as an industrial designer to design the industrial layout and plan for setting up of a manufacturing industry or as an industrial technician to lookover the technical requirements and repairing of the particular factory.\nRobotics.\nRobotics is one of the newest emerging subfield of mechatronics. It is the study of robots that how they are manufactured and operated. Since 2000, this branch of mechatronics is attracting a number of aspirants. Robotics is interrelated with automation because here also not much human intervention is required. A large number of factories especially in automobile factories, robots are founds in assembly lines where they perform the job of drilling, installation and fitting. Programming skills are necessary for specialization in robotics. Knowledge of programming language —ROBOTC is important for functioning robots. An industrial robot is a prime example of a mechatronics system; it includes aspects of electronics, mechanics, and computing to do its day-to-day jobs.\nComputer.\nThe Internet of things (IoT) is the inter-networking of physical devices, embedded with electronics, software, sensors, actuators, and network connectivity which enable these objects to collect and exchange data. IoT and mechatronics are complementary. Many of the smart components associated with the Internet of Things will be essentially mechatronic. The development of the IoT is forcing mechatronics engineers, designers, practitioners and educators to research the ways in which mechatronic systems and components are perceived, designed and manufactured. This allows them to face up to new issues such as data security, machine ethics and the human-machine interface.\nKnowledge of programming is very important. A mechatronics engineer has to do programming in different levels example.—PLC programming, drone programming, hardware programming, CNC programming etc. Due to combination of electronics engineering, soft skills from computer side is important. Important programming languages for mechatronics engineer to learn is Java, Python, C++ and C programming language.", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "15944570", "revid": "40561892", "url": "https://en.wikipedia.org/wiki?curid=15944570", "title": "Sheet of stamps", "text": "A sheet of stamps or press sheet is a unit of stamps as printed, usually on large sheets of paper based on the size of the printing plate, that are separated into panes that are sold at post offices. Where more than one pane is on a printed sheet they are arranged in a table-like arrangement. The spaces between the single stamps are all of the same size and provide space for a cut or perforation.\nSize and format.\nToday, a sheet of stamps is the most common way of arranging stamps on the impressed paper. The number of stamps on a sheet and the format of the sheet depend on the size and format of the individual stamps. Small stamps are usually printed on sheets of a hundred stamps, although the Penny Black, as with other pre-decimal sterling currency stamps, were printed in sheets of 240; larger stamps are printed on sheets of fifty, twenty-five or twenty, as is done by the USPS.\nOn November 13, 1994, the Deutsche Post changed the format of its emissions to sheets of ten stamps each, due to reasons of efficiency. The edges of these sheets are specially designed, making them a novel field of collecting.\nPrinting sheet.\nIn fact, the term printing sheet refers only to a part of the actual \"printing sheet\". This is because stamps are mostly printed in four connected sheets, to make best use of the stamp paper. At the post office counter, only the four separated printing sheets are sold. Therefore, the sheet of stamps is also called a counter sheet or pane, though improperly called a sheet of stamps.\nGutters.\nThe empty fields connecting the single counter sheets are called gutters. Normally they are separated in the middle after printing in order to obtain four counter sheets. The half empty fields or gutters then form the edge of the sheet. However, from many issues, unseparated gutters with connected stamps of the neighbouring sheets come on the market (stamp - empty field - stamp). These gutters may be either empty or printed, if printed edges were intended.\nThe philatelist makes a distinction between \"horizontal and vertical gutters\". A specific characteristic of the gutters is the \"heart\" of the printing sheet, where all four panes are connected. Gutters and hearts are very popular with collectors and reach high catalog prices, especially for classic issues.\nTête-bêche.\nSingle counter sheets do not always have to be separated by empty fields. Issues which were not intended to have edges were naturally manufactured without empty fields. To be able to distinguish between the single sheets better, the stamps were printed rotated 180° to each other along the separation line. Philatelists describe the two stamps which are upside down in relationship to each other as tête-bêche. Some issues have tête-bêches as well as gutters.\nLike gutters, tête-bêches are very popular with collectors due to their scarcity and decorativeness.\nStamp arrangement and location.\nThe stamps are arranged on the sheet in a table with rows and columns. Due to this arrangement, the location of each stamp can be precisely determined. The philatelist counts the single stamps horizontally from left to right, but the post counts them vertically from top to bottom. Accordingly, the third stamp in the sixth row of a sheet of 10 x 10 would be the 53rd stamp of the sheet for the collector, but the 26th stamp for the post.\nThe first postage stamps of the UK, the Penny Black, were printed in sheets of 20 rows and 12 columns, but the location on the sheet was indicated by different letters in the bottom corners of each stamp. An \"A\" in the lower left corner indicated the first row, a \"B\" the second one, the \"C\" the third one, etc. The columns were indicated according to the same scheme in the lower right corner. Thus the top left stamp had the letter combination \"A\" - \"A\", the bottom right stamp had \"T\" - \"L\". As a result, 240 different stamps were made for each plate used. This was intended to prevent forgery.\nSheet edge.\nThe term \"sheet edge\" refers to the empty fields connected to the stamps and arranged around the sheet. These fields are often unprinted. However, in many cases, quite a bit of interesting information can be found on them, e.g. printing dates or the like. The most important inscriptions printed on the edges of the sheet are:\nSpecialities.\nThere are several specialities of the printing of sheets. The most important are:", "Engineering,_Manufacturing": 0.985059917, "qwen": "Yes"}
{"id": "27152664", "revid": "34390653", "url": "https://en.wikipedia.org/wiki?curid=27152664", "title": "General Magnaplate", "text": "General Magnaplate is a company that researches and produces surface coatings for metals.\nOne of its products, Hi-T-Lube, is recognized by the Guinness Book of World Records as the \"world's most slippery solid\".", "Engineering,_Manufacturing": 1.0000084639, "qwen": "Yes"}
{"id": "568715", "revid": "1169574196", "url": "https://en.wikipedia.org/wiki?curid=568715", "title": "Packaging and labeling", "text": "Packaging is the science, art and technology of enclosing or protecting products for distribution, storage, sale, and use. Packaging also refers to the process of designing, evaluating, and producing packages. Packaging can be described as a coordinated system of preparing goods for transport, warehousing, logistics, sale, and end use. Packaging contains, protects, preserves, transports, informs, and sells. In many countries it is fully integrated into government, business, institutional, industrial, and personal use.\nPackage labeling (American English) or labelling (British English) is any written, electronic, or graphic communication on the package or on a separate but associated label.\nHistory of packaging.\nAncient era.\nThe first packages used the natural materials available at the time: baskets of reeds, wineskins (bota bags), wooden boxes, pottery vases, ceramic amphorae, wooden barrels, woven bags, etc. Processed materials were used to form packages as they were developed: first glass and bronze vessels. The study of old packages is an essential aspect of archaeology.\nThe first usage of paper for packaging was sheets of treated mulberry bark used by the Chinese to wrap foods as early as the first or second century BC.\nThe usage of paper-like material in Europe was when the Romans used low grade and recycled papyrus for the packaging of incense.\nThe earliest recorded use of paper for packaging dates back to 1035, when a Persian traveller visiting markets in Cairo, Arab Egypt, noted that vegetables, spices and hardware were wrapped in paper for the customers after they were sold.\nModern era.\nTinplate.\nThe use of tinplate for packaging dates back to the 18th century. The manufacturing of tinplate was the monopoly of Bohemia for a long time; in 1667 Andrew Yarranton, an English engineer, and Ambrose Crowley brought the method to England where it was improved by ironmasters including Philip Foley. By 1697, John Hanbury had a rolling mill at Pontypool for making \"Pontypoole Plates\". The method pioneered there of rolling iron plates by means of cylinders enabled more uniform black plates to be produced than was possible with the former practice of hammering.\nTinplate boxes first began to be sold from ports in the Bristol Channel in 1725. The tinplate was shipped from Newport, Monmouthshire. By 1805, 80,000 boxes were made and 50,000 exported. Tobacconists in London began packaging snuff in metal-plated canisters from the 1760s onwards.\nCanning.\nWith the discovery of the importance of airtight containers for food preservation by French inventor Nicholas Appert, the tin canning process was patented by British merchant Peter Durand in 1810. After receiving the patent, Durand did not himself follow up with canning food. He sold his patent in 1812 to two other Englishmen, Bryan Donkin and John Hall, who refined the process and product and set up the world's first commercial canning factory on Southwark Park Road, London. By 1813, they were producing the first canned goods for the Royal Navy.\nThe progressive improvement in canning stimulated the 1855 invention of the can opener. Robert Yeates, a cutlery and surgical instrument maker of Trafalgar Place West, Hackney Road, Middlesex, UK, devised a claw-ended can opener with a hand-operated tool that haggled its way around the top of metal cans. In 1858, another lever-type opener of a more complex shape was patented in the United States by Ezra Warner of Waterbury, Connecticut.\nPaper-based packaging.\nSet-up boxes were first used in the 16th century and modern folding cartons date back to 1839. The first corrugated box was produced commercially in 1817 in England. Corrugated (also called pleated) paper received a British patent in 1856 and was used as a liner for tall hats. Scottish-born Robert Gair invented the pre-cut paperboard box in 1890—flat pieces manufactured in bulk that folded into boxes. Gair's invention came about as a result of an accident: as a Brooklyn printer and paper-bag maker during the 1870s, he was once printing an order of seed bags, and the metal ruler, commonly used to crease bags, shifted in position and cut them. Gair discovered that by cutting and creasing in one operation he could make prefabricated paperboard boxes.\nCommercial paper bags were first manufactured in Bristol, England, in 1844, and the American Francis Wolle patented a machine for automated bag-making in 1852.\n20th century.\nPackaging advancements in the early 20th century included Bakelite closures on bottles, transparent cellophane overwraps and panels on cartons. These innovations increased processing efficiency and improved food safety. As additional materials such as aluminum and several types of plastic were developed, they were incorporated into packages to improve performance and functionality.\nIn 1952, Michigan State University became the first university in the world to offer a degree in Packaging Engineering.\nIn-plant recycling has long been typical for producing packaging materials. Post-consumer recycling of aluminum and paper-based products has been economical for many years: since the 1980s, post-consumer recycling has increased due to curbside recycling, consumer awareness, and regulatory pressure.\nMany prominent innovations in the packaging industry were developed first for military use. Some military supplies are packaged in the same commercial packaging used for general industry. Other military packaging must transport materiel, supplies, foods, etc. under severe distribution and storage conditions. Packaging problems encountered in World War II led to Military Standard or \"mil spec\" regulations being applied to packaging, which was then designated \"military specification packaging\". As a prominent concept in the military, mil spec packaging officially came into being around 1941, due to operations in Iceland experiencing critical losses, ultimately attributed to bad packaging. In most cases, mil spec packaging solutions (such as barrier materials, field rations, antistatic bags, and various shipping crates) are similar to commercial grade packaging materials, but subject to more stringent performance and quality requirements.\n, the packaging sector accounted for about two percent of the gross national product in developed countries. About half of this market was related to food packaging.\nIn 2019 the global food packaging market size was estimated at USD 303.26 billion, exhibiting a CAGR of 5.2% over the forecast period. Growing demand for packaged food by consumers owing to quickening pace of life and changing eating habits is expected to have a major impact on the market.\nThe purposes of packaging and package labels.\nPackaging and package labeling have several objectives\nPackaging types.\nPackaging may be of several different types. For example, a \"transport package\" or \"distribution package\" can be the shipping container used to ship, store, and handle the product or inner packages. Some identify a \"consumer package\" as one which is directed toward a consumer or household.\nPackaging may be described in relation to the type of product being packaged: medical device packaging, bulk chemical packaging, over-the-counter drug packaging, retail food packaging, military materiel packaging, pharmaceutical packaging, etc.\nIt is sometimes convenient to categorize packages by layer or function: \"primary\", \"secondary\", etc.\nThese broad categories can be somewhat arbitrary. For example, depending on the use, a shrink wrap can be primary packaging when applied directly to the product, secondary packaging when used to combine smaller packages, or tertiary packaging when used to facilitate some types of distribution, such as to affix a number of cartons on a pallet.\nPackaging can also have categories based on the package form. For example, \"thermoform packaging\" and \"flexible packaging\" describe broad usage areas.\nLabels and symbols used on packages.\nMany types of symbols for package labeling are nationally and internationally standardized. For consumer packaging, symbols exist for product certifications (such as the FCC and TÜV marks), trademarks, proof of purchase, etc. Some requirements and symbols exist to communicate aspects of consumer rights and safety, for example the CE marking or the estimated sign that notes conformance to EU weights and measures accuracy regulations. Examples of environmental and recycling symbols include the recycling symbol, the recycling code (which could be a resin identification code), and the \"Green Dot\". Food packaging may show food contact material symbols. In the European Union, products of animal origin which are intended to be consumed by humans have to carry standard, oval-shaped EC identification and health marks for food safety and quality insurance reasons.\nBar codes, Universal Product Codes, and RFID labels are common to allow automated information management in logistics and retailing. Country-of-origin labeling is often used. Some products might use QR codes or similar matrix barcodes. Packaging may have visible registration marks and other printing calibration and troubleshooting cues.\nThe labelling of medical devices includes many symbols, many of them covered by international standards, foremost ISO 15223-1.\nConsumer package contents.\nSeveral aspects of consumer package labeling are subject to regulation. One of the most important is to accurately state the quantity (weight, volume, count) of the package contents. Consumers expect that the label accurately reflects the actual contents. Manufacturers and packagers must have effective quality assurance procedures and accurate equipment; even so, there is inherent variability in all processes.\nRegulations attempt to handle both sides of this. In the USA, the Fair Packaging and Labeling Act provides requirements for many types of products. Also, NIST has Handbook 133, Checking the Net Contents of Packaged Goods. This is a procedural guide for compliance testing of net contents and is referenced by several other regulatory agencies.\nOther regions and countries have their own regulatory requirements. For example, the UK has its Weights and Measures (Packaged Goods) Regulations as well as several other regulations. In the EEA, products with hazardous formulas need to have a UFI.\nShipping container labeling.\nTechnologies related to shipping containers are identification codes, bar codes, and electronic data interchange (EDI). These three core technologies serve to enable the business functions in the process of shipping containers throughout the distribution channel. Each has an essential function: identification codes either relate product information or serve as keys to other data, bar codes allow for the automated input of identification codes and other data, and EDI moves data between trading partners within the distribution channel.\nElements of these core technologies include UPC and EAN item identification codes, the SCC-14 (UPC shipping container code), the SSCC-18 (Serial Shipping Container Codes), Interleaved 2-of-5 and UCC/EAN-128 (newly designated GS1-128) bar code symbologies, and ANSI ASC X12 and UN/EDIFACT EDI standards.\nSmall parcel carriers often have their own formats. For example, United Parcel Service has a MaxiCode 2-D code for parcel tracking.\nRFID labels for shipping containers are also increasingly used. A Wal-Mart division, Sam's Club, has also moved in this direction and is putting pressure on its suppliers to comply.\nShipments of hazardous materials or dangerous goods have special information and symbols (labels, placards, etc.) as required by UN, country, and specific carrier requirements. On transport packages, standardized symbols are also used to communicate handling needs. Some are defined in the ASTM D5445 \"Standard Practice for Pictorial Markings for Handling of Goods\" and ISO 780 \"Pictorial marking for handling of goods\".\nPackage development considerations.\nPackage design and development are often thought of as an integral part of the new product development process. Alternatively, the development of a package (or component) can be a separate process but must be linked closely with the product to be packaged.\nPackage design starts with the identification of all the requirements: structural design, marketing, shelf life, quality assurance, logistics, legal, regulatory, graphic design, end-use, environmental, etc. The design criteria, performance (specified by package testing), completion time targets, resources, and cost constraints need to be established and agreed upon. Package design processes often employ rapid prototyping, computer-aided design, computer-aided manufacturing and document automation.\nAn example of how package design is affected by other factors is its relationship to logistics. When the distribution system includes individual shipments by a small parcel carrier, the sorting, handling, and mixed stacking make severe demands on the strength and protective ability of the transport package. If the logistics system consists of uniform palletized unit loads, the structural design of the package can be designed to meet those specific needs, such as vertical stacking for a longer time frame. A package designed for one mode of shipment may not be suited to another.\nWith some types of products, the design process involves detailed regulatory requirements for the packaging. For example, any package components that may contact foods are designated food contact materials.\nToxicologists and food scientists need to verify that such packaging materials are allowed by applicable regulations. Packaging engineers need to verify that the completed package will keep the product safe for its intended shelf life with normal usage. Packaging processes, labeling, distribution, and sale need to be validated to assure that they comply with regulations that have the well being of the consumer in mind.\nSometimes the objectives of package development seem contradictory. For example, regulations for an over-the-counter drug might require the package to be tamper-evident and child resistant: These intentionally make the package difficult to open. The intended consumer, however, might be disabled or elderly and unable to readily open the package. Meeting all goals is a challenge.\nPackage design may take place within a company or with various degrees of external packaging engineering: independent contractors, consultants, vendor evaluations, independent laboratories, contract packagers, total outsourcing, etc. Some sort of formal project planning and project management methodology is required for all but the simplest package design and development programs. An effective quality management system and Verification and Validation protocols are mandatory for some types of packaging and recommended for all.\nEnvironmental considerations.\nPackage development involves considerations of sustainability, environmental responsibility, and applicable environmental and recycling regulations. It may involve a life cycle assessment\nwhich considers the material and energy inputs and outputs to the package, the packaged product (contents), the packaging process, the logistics system, waste management, etc. It is necessary to know the relevant regulatory requirements for point of manufacture, sale, and use.\nThe traditional \"three R's\" of reduce, reuse, and recycle are part of a waste hierarchy which may be considered in product and package development.\nDevelopment of sustainable packaging is an area of considerable interest to standards organizations, governments, consumers, packagers, and retailers.\nSustainability is the fastest-growing driver for packaging development, particularly for packaging manufacturers that work with the world's leading brands, as their CSR (Corporate Social Responsibility) targets often exceed those of the EU Directive.\nPackaging machinery.\nChoosing packaging machinery includes an assessment of technical capabilities, labor requirements, worker safety, maintainability, serviceability, reliability, ability to integrate into the packaging line, capital cost, floorspace, flexibility (change-over, materials, multiple products, etc.), energy requirements, quality of outgoing packages, qualifications (for food, pharmaceuticals, etc.), throughput, efficiency, productivity, ergonomics, return on investment, etc.\nPackaging machinery can be:\nEfforts at packaging line automation increasingly use programmable logic controllers and robotics.\nPackaging machines may be of the following general types:", "Engineering,_Manufacturing": 0.9997484088, "qwen": "Yes"}
{"id": "967654", "revid": "12120664", "url": "https://en.wikipedia.org/wiki?curid=967654", "title": "Bottling line", "text": "Bottling lines are production lines that fill a product, generally a beverage, into bottles on a large scale. Many prepared foods are also bottled, such as sauces, syrups, marinades, oils and vinegars.\nBeer bottling process.\nPackaging of bottled beer typically involves drawing the product from a holding tank and filling it into bottles in a filling machine (\"filler\"), which are then capped, labeled and packed into cases or cartons. Many smaller breweries send their bulk beer to large facilities for contract bottling—though some will bottle by hand. Virtually all beer bottles are glass.\nThe first step in bottling beer is \"depalletising\", where the empty bottles are removed from the original pallet packaging delivered from the manufacturer, so that individual bottles may be handled. The bottles may then be rinsed with filtered water or air, and may have carbon dioxide injected into them in attempt to reduce the level of oxygen within the bottle. The bottle then enters a \"filler\" which fills the bottle with beer and may also inject a small amount of inert gas (usually carbon dioxide or nitrogen) on top of the beer to disperse the oxygen, as oxygen can ruin the quality of the product via oxidation. Finally, the bottles go through a \"capper\", which applies a bottle cap, sealing the bottle. A few beers are bottled with a cork and cage.\nNext the bottle enters a labelling machine (\"labeller\") where a label is applied. To ensure traceability of the product, a \"lot number\", generally the date and time of bottling, may also be printed on the bottle. The product is then packed into boxes and warehoused, ready for sale.\nDepending on the magnitude of the bottling endeavor, there are many different types of bottling machinery available. Liquid level machines fill bottles so they appear to be filled to the same line on every bottle, while volumetric filling machines fill each bottle with exactly the same amount of liquid. Overflow pressure fillers are the most popular machines with beverage makers, while gravity filling machines are most cost effective. In terms of automation, inline filling machines are most popular, but rotary machines are much faster albeit much more expensive.\nWine bottling process.\nThe process for bottling wine is largely similar to that for bottling beer, except wine bottles differ in volumes and shapes. Traditionally, a cork is used to provide closure to wine bottles. After filling, a bottle travels to a corking machine (\"corker\") where a cork is compressed and pushed into the neck of the bottle. Whilst this is happening, the corker vacuums the air out of the bottle to form a negative pressure \"headspace\". This removes any oxygen from the headspace, which is useful as latent oxygen can ruin the quality of the product via oxidation. A negative pressure headspace will also counteract pressure caused by the thermal expansion of the wine, preventing the cork from being forced from the bottle. Champagnes and sparkling wines may further be sealed with a muselet, which ensures the cork will not explode off in transit. Alternative wine closures such as screw caps are available.\nSome bottling lines incorporate a \"fill height detector\" which reject under or over-filled bottles, and also a metal detector.\nAfter filling and corking, a plastic or tin capsule is applied to the neck of the bottle in a \"capsular\". Next the bottle enters a \"labeller\" where a wine label is applied. The product is then packed into boxes and warehoused, ready for sale.", "Engineering,_Manufacturing": 0.9999405146, "qwen": "Yes"}
{"id": "59600751", "revid": "3608035", "url": "https://en.wikipedia.org/wiki?curid=59600751", "title": "IR welding", "text": "IR welding is a welding technique that uses a non-contact heating method to melt and fuse thermoplastic parts together using the energy from infrared radiation. The process was first developed in the late 1900s, but due to the high capital cost of IR equipment the process was not commonly applied in industry until prices dropped in the 1990s. IR welding typically uses a range of wavelengths from 800 to 11,000 nm on the electromagnetic spectrum to heat, melt, and fuse the interface between two plastic parts through the absorption and conversion of the IR energy into heat. Laser welding is a similar joining process that applies IR radiation at a single wavelength.\nThere are many different welding techniques that use IR heating, with the three major modes being surface heating, through transmission IR welding (TTIr), and IR staking. A variety of heating configurations have been applied to these techniques such as scanning, continuous illumination, and mask welding. Advantages such as faster and controllable non-contact heating applicable for a wide range of simple or complex part geometries sets IR welding apart from other forms of plastic welding. CO detectors, IV bags, and brake transmission lines are just a few of the many products that utilize IR welds.\nHistory.\nIR welding is categorized as a form thermal plastic welding alongside hot gas welding, hot tool welding, and extrusion welding. Although infrared radiation was first discovered in the 1800s, IR was not applied as a source of heat until the beginning of WWII when it was found to be more effective than the fuel convection ovens of that time. IR radiation was first tested for the welding of thermoplastic polymers in the late 1900s, but the process was relatively new and not fully understood. IR welding systems offered faster heating times than the other forms of thermal welding, but the high capital costs limited its development. With a decrease in the price of equipment in the 1990s, IR welding has become more popular in the industry.\nPhysics of IR welding.\nIR welding typically uses wavelengths from 800 to 11,000 nm on the electromagnetic spectrum. Plastics interact with IR radiation through reflection, transmission, and absorption. Incident IR radiation can either be reflected off the surface of the plastic, transmitted through the plastic, or absorbed into the plastic as other forms of energy including thermal energy. The ratio of these three interactions depends on the wavelength of the IR radiation and the receiving plastic's properties. Amorphous plastics are generally optically clear and can transmit almost all incident IR radiation. For this reason they are commonly used in TTIr. Semi-crystalline plastics can diffuse incident IR radiation between the amorphous and crystalline boundaries, reducing the transmittance and increasing the absorbance of the material. The higher absorptivity results in more heat generation for a given IR source. Additives such as clarifying agents can be used increase a plastic's transmittance while dies and pigments can be used increase the absorbance of a material. Increasing amounts of these additives can decrease the strength of both the material and the welded joint.\nThe closer the IR radiation source, the higher incidence efficiency on the material. IR radiation is most effective when directing radiation normal to the part. Radiation energy always affects the surface of a part while the depth of penetration that the energy can reach is dependent on the plastic's crystallinity.\nEquipment.\nIR Sources.\nPotential IR welding sources include quartz lamps and ceramic heaters which can generate a wide range of IR wavelengths. Laser welding employs IR sources that operate at a single wavelength such as CO2 lasers, s, laser diodes. The equipment selected for each welding process stems from the type of radiation produced. Quartz lamps produce wavelengths of around 1,000 to 5,000 nm and ceramic heaters produce wavelengths of around 5,000 to 10,000 nm.\nAttachments.\nP-wave technology utilizes an IR lamp and a pre-placed focusing device such as an IR transducer or film that can filter and focus IR radiation at a desired wavelength and increased intensity within a selected area to improve weld penetration with minimal surface damage. This method allows improved IR welding of polymers with higher melting temperatures such as most fluoropolymers and polyketones.\nIR welding techniques.\nThe three major welding techniques used in the industry today include surface heating, through transmission IR welding, and IR staking. All IR welding techniques contain the following six basic steps in some form:\nSurface Heating.\nSurface heating includes heating and melting of the interface between plastic parts with IR radiation and forcing the parts together into a molten joint that solidifies as one part. This process can be split into 3 phases as shown in the figure to the right: A) Loading of parts, insertion of the IR source, and IR application. B) Change-over with the removal of IR source and clamping of the parts to join them. C) Unloading of the parts after the weld was made.\nThrough Transmission IR Welding (TTIr).\nTTIr welding is the joining of an IR transparent part to a second part such that the IR radiation travels through the transparent part and heat the surface of the second part as shown in the figure to the right. IR wavelengths are generally within 800 to 1050 nm. To make a transparent part absorbent to IR radiation, the addition of dies or colorants such as carbon black can be used. Highly absorbent thermoplastic films can be placed at the joint to receive the IR radiation and melt the interface during welding. Using these methods, TTIr welds can be completed between parts of both the same or different materials. \nIR Staking.\nIR staking includes the localized welding of a thermoplastic stud or stake from one part into the cavity of a non-weldable part to form a mechanical fastener. As shown in the figure to the right, the polymer part and non-weldable part are first placed together (A), then the projecting polymer is melted and formed around the non-weldable part to fasten the two together (B). The stud can be heated through directed TTIr when pre-placed within the cavity of an IR transparent part, then melted to deform it into a button shape required to fill the cavity before solidifying. Surface IR radiation can also be used to soften a plastic stud which is then pressed into a button-shaped die to form a head before cooling and solidifying.\nHeating Configurations.\nIR systems generally rely on one of three surface heating methods: scanning, continuous illumination, and mask welding.\nScanning.\nScanning involves the movement of an IR beam across the surface of a part using either an automated motion system or galvanic mirrors. Equipment is limited by the speed of movements across the part's surface to maintain uniform temperatures on the surface. In TTIr welding, scanning allows the un-melted portion of the part to act as a mechanical stop in order to maintain the joint gap between the two parts.\nContinuous illumination.\nContinuous illumination uses more than one IR radiation source to heat the entire joint interface at the same time. Part tolerances or fit is not as crucial with this method as the entire surface will be melted before welding. This method is useful when welding parts with complex geometries, employing the multiple IR sources to evenly heat all forms of joint interfaces.\nMask welding.\nSimilar to continuous illumination, mask welding utilizes multiple IR sources to completely illuminate a joint interface while placing an IR radiation mask over the parts to control which regions will form a melt layer.\nMaterials.\nBelow is a list of materials well known for their IR weldability:\nApplications.\nNew joining technologies using IR welding are critical for fabricating complex parts and assemblies at high speeds and low costs. Although IR plastic welding has many advantages over other types of plastic welding, limitations such as equipment costs and susceptible materials properties reduce the amount of industrial applications of the method. A few examples of current industrial applications are shown below:", "Engineering,_Manufacturing": 0.9997023344, "qwen": "Yes"}
{"id": "59603661", "revid": "910180", "url": "https://en.wikipedia.org/wiki?curid=59603661", "title": "Interconnect (integrated circuits)", "text": "In integrated circuits (ICs), interconnects are structures that connect two or more circuit elements (such as transistors) together electrically. The design and layout of interconnects on an IC is vital to its proper function, performance, power efficiency, reliability, and fabrication yield. The material interconnects are made from depends on many factors. Chemical and mechanical compatibility with the semiconductor substrate and the dielectric between the levels of interconnect is necessary, otherwise barrier layers are needed. Suitability for fabrication is also required; some chemistries and processes prevent the integration of materials and unit processes into a larger technology (recipe) for IC fabrication. In fabrication, interconnects are formed during the back-end-of-line after the fabrication of the transistors on the substrate.\nInterconnects are classified as \"local\" or \"global\" interconnects depending on the signal propagation distance it is able to support. The width and thickness of the interconnect, as well as the material from which it is made, are some of the significant factors that determine the distance a signal may propagate. Local interconnects connect circuit elements that are very close together, such as transistors separated by ten or so other contiguously laid out transistors. Global interconnects can transmit further, such as over large-area sub-circuits. Consequently, local interconnects may be formed from materials with relatively high electrical resistivity such as polycrystalline silicon (sometimes silicided to extend its range) or tungsten. To extend the distance an interconnect may reach, various circuits such as buffers or restorers may be inserted at various points along a long interconnect.\nInterconnect properties.\nThe geometric properties of an interconnect are width, thickness, spacing (the distance between an interconnect and another on the same level), pitch (the sum of the width and spacing), and aspect ratio, or AR, (the thickness divided by width). The width, spacing, AR, and ultimately, pitch, are constrained in their minimum and maximum values by design rules that ensure the interconnect (and thus the IC) can be fabricated by the selected technology with a reasonable yield. Width is constrained to ensure minimum width interconnects do not suffer breaks, and maximum width interconnects can be planarized by chemical mechanical polishing (CMP). Spacing is constrained to ensure adjacent interconnects can be fabricated without any conductive material bridging. Thickness is determined solely by the technology, and the aspect ratio, by the chosen width and set thickness. In technologies that support multiple levels of interconnects, each group of contiguous levels, or each level, has its own set of design rules.\nBefore the introduction of CMP for planarizing IC layers, interconnects had design rules that specified larger minimum widths and spaces than the lower level to ensure that the underlying layer's rough topology did not cause breaks in the interconnect formed on top. The introduction of CMP has made finer geometries possible.\nThe AR is an important factor. In technologies that form interconnect structures with conventional processes, the AR is limited to ensure that the etch creating the interconnect, and the dielectric deposition that fills the voids in between interconnects with dielectric, can be done successfully. In those that form interconnect structures with damascene processes, the AR must permit successful etch of the trenches, deposition of the barrier metal (if needed) and interconnect material.\nInterconnect layout are further restrained by design rules that apply to collections of interconnects. For a given area, technologies that rely on CMP have \"density rules\" to ensure the whole IC has an acceptable variation in interconnect density. This is because the rate at which CMP removes material depends on the material's properties, and great variations in interconnect density can result in large areas of dielectric which can dish, resulting in poor planarity. To maintain acceptable density, \"dummy interconnects\" (or \"dummy wires\") are inserted into regions with spare interconnect density.\nHistorically, interconnects were routed in straight lines, and could change direction by using sections aligned 45° away from the direction of travel. As IC structure geometries became smaller, to obtain acceptable yields, restrictions were imposed on interconnect direction. Initially, only global interconnects were subject to restrictions; were made to run in straight lines aligned eastwest or northsouth. To allow easy routing, alternate levels of interconnect ran in the same alignment, so that changes in direction were achieved by connecting to a lower or upper level of interconnect though a via. Local interconnects, especially the lowest level (usually polysilicon) could assume a more arbitrary combination of routing options to attain the a higher packing density.\nMaterials.\nIn silicon ICs, the most commonly used semiconductor in ICs, the first interconnects were made of aluminum. Aluminum was an ideal material for interconnects due to its ease of deposition and good adherence to silicon and silicon dioxide. Al interconnects are deposited by physical vapor deposition or chemical vapor deposition methods. They were originally patterned by wet etching, and later by various dry etching techniques.\nInitially, pure aluminum was used but by the 1970s, substrate compatibility, junction spiking and reliability concerns (mostly concerning electromigration) forced the use of aluminum-based alloys containing silicon, copper, or both. By the late 1990s, the high resistivity of aluminum, coupled with the narrow widths of the interconnect structures forced by continuous feature size downscaling, resulted in prohibitively high resistance in interconnect structures. This forced aluminum's replacement by copper interconnects.\nIn gallium arsenide (GaAs) ICs, which have been mainly used in application domains (e.g. monolithic microwave ICs) different to those of silicon, the predominant material used for interconnects is gold.\nPerformance enhancements.\nTo reduce the delay penalty caused by parasitic capacitance, the dielectric material used to insulate adjacent interconnects, and interconnects on different levels (the inter-level dielectric [ILD]), should have a dielectric constant that is as close to 1 as possible. A class of such materials, Low-κ dielectrics, were introduced during the late 1990s and early 2000s for this purpose. As of January 2019, the most advanced materials reduce the dielectric constant to very low levels through highly porous structures, or through the creation of substantial air or vacuum pockets (air gap dielectric). These materials often have low mechanical strength and are restricted to the lowest level or levels of interconnect as a result. The high density of interconnects at the lower levels, along with the minimal spacing, helps support the upper layers. Intel introduced air-gap dielectric in its 14nm technology in 2014.\nMulti-level interconnects.\nIC with complex circuits require multiple levels of interconnect to form circuits that have minimal area. As of 2018, the most complex ICs may have over 15 layers of interconnect. Each level of interconnect is separated from each other by a layer of dielectric. To make vertical connections between interconnects on different levels, vias are used. The top-most layers of a chip have the thickest and widest and most widely separated metal layers, which make the wires on those layers have the least resistance and smallest RC time constant, so they are used for power and clock distribution networks. The bottom-most metal layers of the chip, closest to the transistors, have thin, narrow, tightly-packed wires, used only for local interconnect. Adding layers can potentially improve performance, but adding layers also reduces yield and increases manufacturing costs. ICs with a single metal layer typically use the polysilicon layer to \"jump across\" when one signal needs to cross another signal.\nThe process used to form DRAM capacitors creates a rough and hilly surface, which makes it difficult to add metal interconnect layers and still maintain good yield.\nIn 1998, state-of-the-art DRAM processes had four metal layers, while state-of-the-art logic processes had seven metal layers.\nIn 2002, five or six layers of metal interconnect was common.\nIn 2009, 1Gbit DRAM typically had three layers of metal interconnect; tungsten for the first layer and aluminum for the upper layers.", "Engineering,_Manufacturing": 0.9987857938, "qwen": "Yes"}
{"id": "185325", "revid": "45431779", "url": "https://en.wikipedia.org/wiki?curid=185325", "title": "Coining (metalworking)", "text": "Coining is a form of precision stamping in which a workpiece is subjected to a sufficiently high stress to induce plastic flow on the surface of the material. A beneficial feature is that in some metals, the plastic flow reduces surface grain size, and work hardens the surface, while the material deeper in the part retains its toughness and ductility. The term comes from the initial use of the process: manufacturing of coins.\nCoining is used to manufacture parts for all industries and is commonly used when high relief or very fine features are required. For example, it is used to produce coins, badges, buttons, precision-energy springs and precision parts with small or polished surface features.\nCoining is a cold working process similar in other respects to forging, which takes place at elevated temperature; it uses a great deal of force to elastically deform a workpiece, so that it conforms to a die. Coining can be done using a gear driven press, a mechanical press, or more commonly, a hydraulically actuated press. Coining typically requires higher tonnage presses than stamping, because the workpiece is elastically deformed and not actually cut, as in some other forms of stamping. The coining process is preferred when there is a high tonnage. \nCoining in electronic industry.\nIn soldering of electronic components, bumps are formed on bonding pads to enhance adhesion, which are further flattened by the coining process. Unlike typical coining applications, in this case the goal of coining is to create a flat, rather than patterned, surface.", "Engineering,_Manufacturing": 1.0000052452, "qwen": "Yes"}
{"id": "1617255", "revid": "659390845", "url": "https://en.wikipedia.org/wiki?curid=1617255", "title": "Pritchel", "text": "A pritchel is a type of punch used in forging, particularly in making nail holes in horseshoes. The horseshoe is heated and a hole is punched through 90 percent of the steel with a forepunch or drift punch. The pointed end of the tool should be kept sharp and so that the burr is cut out smoothly. The punched hole is lined up over the pritchel hole and the pritchel is driven into the hole, knocking out the remaining metal at the bottom of the punched hole. \nThe temperature of the pritchel should be always below the \"red-hot\" stage as the tool itself will bend and lose the temper. When over-heated it is advised to cool it in water intermediately.\nBack pritcheling.\nThe pritchel should normally be driven from the bottom of the shoe, similarly as the nail is driven. \"Back pritcheling\" is the process of driving it from the opposite side —the hoof side— leaving burrs and resulting in the weakening and cutting the nails.\nPritchel hole.\nA pritchel hole is a round hole in an anvil. Its primary purpose is to provide clearance for punching tools, but it can also be used to hold tools that have round shanks. Pritchel tools are tools such as punches whose functions do not require them to be held at a particular orientation. A square hole in an anvil is called a Hardy hole, not to be confused with\ntapered square holes seen in tinsmith's equipment.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "1619127", "revid": "141808", "url": "https://en.wikipedia.org/wiki?curid=1619127", "title": "Shot peening", "text": "Shot peening is a cold working process used to produce a compressive residual stress layer and modify the mechanical properties of metals and composites. It entails striking a surface with shot (round metallic, glass, or ceramic particles) with force sufficient to create plastic deformation.\nIn machining, shot peening is used to strengthen and relieve stress in components like steel automobile crankshafts and connecting rods. In architecture it provides a muted finish to metal.\nShot peening is similar mechanically to sandblasting, though its purpose is not to remove material, but rather it employs the mechanism of plasticity to achieve its goal, with each particle functioning as a ball-peen hammer.\nDetails.\nPeening a surface spreads it plastically, causing changes in the mechanical properties of the surface. Its main application is to avoid the propagation of microcracks in a surface. By putting a material under compressive stress, shot peening prevents such cracks from propagating.\nShot peening is often called for in aircraft repairs to relieve tensile stresses built up in the grinding process and replace them with beneficial compressive stresses. Depending on the part geometry, part material, shot material, shot quality, shot intensity, and shot coverage, shot peening can increase fatigue life up to 1000%.\nPlastic deformation induces a residual compressive stress in a peened surface, along with tensile stress in the interior. Surface compressive stresses confer resistance to metal fatigue and to some forms of stress corrosion. The tensile stresses deep in the part are not as troublesome as tensile stresses on the surface because cracks are less likely to start in the interior.\n\"Intensity\" is a key parameter of the shot peening process. After some development of the process, an analog was needed to measure the effects of shot peening. John Almen noticed that shot peening made the side of the sheet metal that was exposed begin to bend and stretch. He created the Almen strip to measure the compressive stresses in the strip created by the shot peening operation. One can obtain what is referred to as the \"intensity of the blast stream\" by measuring the deformation on the Almen strip that is in the shot peening operation. As the strip reaches a 10% deformation, the Almen strip is then hit with the same intensity for twice the amount of time. If the strip deforms another 10%, then one obtains the intensity of the blast stream.\nAnother operation to gauge the intensity of a shot peening process is the use of an Almen round, developed by R. Bosshard.\n\"Coverage\", the percentage of the surface indented once or more, is subject to variation due to the angle of the shot blast stream relative to the workpiece surface. The stream is cone-shaped, thus, shot arrives at varying angles. Processing the surface with a series of overlapping passes improves coverage, although variation in \"stripes\" will still be present. Alignment of the axis of the shot stream with the axis of the Almen strip is important. A continuous compressively stressed surface of the workpiece has been shown to be produced at less than 50% coverage but falls as 100% is approached. Optimizing coverage level for the process being performed is important for producing the desired surface effect.\nSAE International's includes several standards for shot peening in aerospace and other industries.\nProcess and equipment.\nPopular methods for propelling shot media include air blast systems and centrifugal blast wheels. In the air blast systems, media are introduced by various methods into the path of high pressure air and accelerated through a nozzle directed at the part to be peened. The centrifugal blast wheel consists of a high speed paddle wheel. Shot media are introduced in the center of the spinning wheel and propelled by the centrifugal force by the spinning paddles towards the part by adjusting the media entrance location, effectively timing the release of the media. Other methods include ultrasonic peening, wet peening, and laser peening (which does not use media).\nMedia choices include spherical cast steel shot, ceramic bead, glass bead or conditioned (rounded) cut wire. Cut wire shot is preferred because it maintains its roundness as it is degraded, unlike cast shot which tends to break up into sharp pieces that can damage the workpiece. Cut wire shot can last five times longer than cast shot. Because peening demands well-graded shot of consistent hardness, diameter, and shape, a mechanism for removing shot fragments throughout the process is desirable. Equipment is available that includes separators to clean and recondition shot and feeders to add new shot automatically to replace the damaged material.\nWheel blast systems include satellite rotation models, rotary throughfeed components, and various manipulator designs. There are overhead monorail systems as well as reverse-belted models. Workpiece holding equipment includes rotating index tables, loading and unloading robots, and jigs that hold multiple workpieces. For larger workpieces, manipulators to reposition them to expose features to the shot blast stream are available.\nCut wire shot.\n\"Cut wire shot\" is a metal shot used for shot peening, where small particles are fired at a workpiece by a compressed air jet. It is a low-cost manufacturing process, as the basic feedstock is inexpensive. As-cut particles are an effective abrasive due to the sharp edges created in the cutting process; however, as-cut shot is not a desirable shot peening medium, as its sharp edges are not suitable to the process.\nCut shot is manufactured from high quality wire in which each particle is cut to a length about equal to its diameter. If required, the particles are conditioned (rounded) to remove the sharp corners produced during the cutting process. Depending on application, various hardness ranges are available, with the higher the hardness of the media the lower its durability.\nOther cut-wire shot applications include tumbling and vibratory finishing.\nCoverage.\nFactors affecting coverage density include: number of impacts (shot flow), exposure time, shot properties (size, chemistry), and work piece properties. Coverage is monitored by visual examination to determine the percent coverage (0-100%). Coverage beyond 100% cannot be determined. The number of individual impacts is linearly proportional to shot flow, exposure area, and exposure time. Coverage is not linearly proportional because of the random nature of the process (chaos theory). When 100% coverage is achieved, locations on the surface have been impacted multiple times. At 150% coverage, 5 or more impacts occur at 52% of locations. At 200% coverage, 5 or more impacts occur at 84% of locations.\nCoverage is affected by shot geometry and the shot and workpiece chemistry. The size of the shot controls how many impacts there are per pound, where smaller shot produces more impacts per pound therefore requiring less exposure time. Soft shot impacting hard material will take more exposure time to reach acceptable coverage compared to hard shot impacting a soft material (since the harder shot can penetrate deeper, thus creating a larger impression).\nCoverage and intensity (measured by Almen strips) can have a profound effect on fatigue life. This can affect a variety of materials typically shot peened. Incomplete or excessive coverage and intensity can result in reduced fatigue life. Over-peening will cause excessive cold working on the surface of the workpiece, which can also cause fatigue cracks. Diligence is required when developing parameters for coverage and intensity, especially when using materials having different properties (i.e. softer metal to harder metal). Testing fatigue life over a range of parameters would result in a \"sweet-spot\" where there is near exponential growth to a peak fatigue life (x = peening intensity or media stream energy, y = time-to-crack or fatigue strength) and rapidly decay fatigue life as more intensity or coverage is added. The \"sweet-spot\" will directly correlate with the kinetic energy transferred and the material properties of the shot media and workpiece.\nApplications.\nShot peening is used on gear parts, cams and camshafts, clutch springs, coil springs, connecting rods, crankshafts, gearwheels, leaf and suspension springs, rock drills, and turbine blades. It is also used in foundries for sand removal, decoring, descaling, and surface finishing of castings such as engine blocks and cylinder heads. Its descaling action can be used in the manufacturing of steel products such as strip, plates, sheets, wire, and bar stock.\nShot peening is a crucial process in spring making. Types of springs include leaf springs, extension springs, and compression springs. The most widely used application are for engine valve springs (compression springs) due to high cyclic fatigue. In an OEM valve spring application, the mechanical design combined with some shot peening ensures longevity. Automotive makers are shifting to more high performance higher stressed valve spring designs as engines evolve. In aftermarket high performance valve spring applications, the need for controlled and multi-step shot peening is a requirement to withstand extreme surface stresses that sometimes exceeds material specifications. The fatigue life of an extreme performance spring (NHRA, IHRA) can be as short as two passes on a 1/4 mile drag racing track before relaxation or failure occurs.\nShot peening may be used for cosmetic effect. The surface roughness resulting from the overlapping dimples causes light to scatter upon reflection. Because peening typically produces larger surface features than sand-blasting, the resulting effect is more pronounced.\nShot peening and abrasive blasting can apply materials on metal surfaces. When the shot or grit particles are blasted through a powder or liquid containing the desired surface coating, the impact plates or coats the workpiece surface. The process has been used to embed ceramic coatings, though the coverage is random rather than coherent. 3M developed a process where a metal surface was blasted with particles with a core of alumina and an outer layer of silica. The result was fusion of the silica to the surface. The process known as peen plating was developed by NASA. Fine powders of metals or non-metals are plated onto metal surfaces using glass bead shot as the blast medium. The process has evolved to applying solid lubricants such as molybdenum disulphide to surfaces. Biocompatible ceramics have been applied this way to biomedical implants. Peen plating subjects the coating material to high heat in the collisions with the shot and the coating must also be available in powder form, limiting the range of materials that can be used. To overcome the problem of heat, a process called temperature moderated-collision mediated coating (TM-CMC) has allowed the use of polymers and antibiotic materials as peened coatings. The coating is presented as an aerosol directed to the surface at the same time as a stream of shot particles. The TM-CMC process is still in the R&D phase of development.\nCompressive residual stress.\nA sub-surface compressive residual stress profile is measured using techniques such as x-ray diffraction and hardness profile testings. The X-axis is depth in mm or inches and the Y-axis is residual stress in ksi or MPa. The maximum residual stress profile can be affected by the factors of shot peening, including: part geometry, part material, shot material, shot quality, shot intensity, and shot coverage. For example, shot peening a hardened steel part with a process and then using the same process for another unhardened part could result in over-peening; causing a sharp decrease in surface residual stresses, but not affecting sub-surface stresses. This is critical because maximum stresses are typically at the surface of the material. Mitigation of these lower surface stresses can be accomplished by a multi-stage post process with varied shot diameters and other surface treatments that remove the low residual stress layer.\nThe compressive residual stress in a metal alloy is produced by the transfer of kinetic energy (K.E.) from a moving mass (shot particle or ball peen) into the surface of a material with the capacity to plastically deform. The residual stress profile is also dependent on coverage density. The mechanics of the collisions involve properties of the shot hardness, shape, and structure; as well as the properties of the workpiece. Factors for process development and the control for K.E. transfer for shot peening are: shot velocity (wheel speed or air pressure/nozzle design), shot mass, shot chemistry, impact angle and work piece properties. Example: if you needed very high residual stresses you would likely want to use large diameter cut-wire shot, a high-intensity process, direct blast onto the workpiece, and a very hard workpiece material.", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "3883623", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=3883623", "title": "Strebor", "text": "Strebor Diecasting (the name comes from Roberts spelled backwards) was a die-casting company in Radcliffe, Lancashire which was founded in 1926 as the Roberts Company. In 1933 the name was changed to the Strebor Diecasting company. During WW2 it made war material, after the war it made metal toys, and eventually achieved widespread notice as makers of cylinder locks and locking devices for the motor trade during the 1960s and 1970s under the STREBOR and STRONIS trade names. Their locks were to be found on British cars such as the Mini. The company was finally dissolved in 2003/2004 following a period of rundown and some industrial relations problems.", "Engineering,_Manufacturing": 1.00000453, "qwen": "Yes"}
{"id": "12115584", "revid": "1023113943", "url": "https://en.wikipedia.org/wiki?curid=12115584", "title": "Dip soldering", "text": "Dip soldering is a small-scale soldering process by which electronic components are soldered to a printed circuit board (PCB) to form an electronic assembly. The solder wets to the exposed metallic areas of the board (those not protected with solder mask), creating a reliable mechanical and electrical connection.\nDip soldering is used for both through-hole printed circuit assemblies, and surface mount. It is one of the cheapest methods to solder and is extensively used in the small scale industries of developing countries .\nDip soldering is the manual equivalent of automated wave soldering. The apparatus required is just a small tank containing molten solder. A PCB with mounted components is dipped manually into the tank so that the molten solder sticks to the exposed metallic areas of the board.\nDip solder process.\nDip soldering is accomplished by submerging parts to be joined into a molten solder bath. Thus, all components surfaces are coated with filler metal. Solders have low surface tension and high wetting capability. There are many types of solders, each used for different applications:\nBecause of the toxicity of lead, lead-free solders are being developed and more widely used. The molten bath can be any suitable filler metal, but the selection is usually confined to the lower melting point elements. The most common dip soldering operations use zinc-aluminum and tin-lead solders.\nProcess schematic.\nThe workpieces to be joined are treated with cleaning flux. Then the workpiece is mounted in the workholding device and immersed in the molten solder for 2 to 12 seconds. The workpiece is often agitated to aid the flow of the solder. The workpiece holder must allow an inclination of so that the solder may run off to ensure a smooth finish.\nWorkpiece geometry.\nThis process is generally limited to all-metal work pieces, although other materials, such as circuit boards can also tolerate momentary contact with the hot molten solder without damage.\nSetup and equipment.\nThere is not much equipment or setup for this process. All that is needed is the solder pot with its temperature control panel, the bath of molten solder, and the work holding device. Usually the work holding device is custom made for each respective workpiece for either manual or automated dipping.\nSolderability.\nSome materials are easier to solder than others. Copper, silver, and gold are easy to solder. Iron and nickel are a little more difficult. Titanium, magnesium, cast irons, steels, ceramics, and graphites are hard to solder. However, if they are first plated they are more easily soldered. An example of this is tin-plating, in which a steel is sheet coated with tin so that it can be soldered more easily.\nApplications.\nDip soldering is used extensively in the electronics industry. However, they have a limited service use at elevated temperatures because of the low melting point of the filler metals. Soldered materials do not have much strength and are therefore not used for load-bearing.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "12683790", "revid": "12120664", "url": "https://en.wikipedia.org/wiki?curid=12683790", "title": "Carton flow", "text": "Carton flow is a form of shelving that uses a gravity feed rear-load design. Each unit consists of one or more inclined runways. Merchandise is loaded in the rear of each runway. As an item is removed from the front, the item directly behind it slides forward in place of the previous.\nThe main advantage of carton flow rack over static rack or shelving systems is that merchandise remains better organized and easier to find or pick. With carton flow rack, the product is automatically rotated on a first-in, first-out basis. Merchandise is stocked in the rear of the carton flow rack and moves toward the picking station in front on an inclined shelf equipped with specially designed roller track. When a carton is removed from the picking station, the next one in line rolls to the front. Carton flow always keeps items within reach. Inventory is easier to monitor and control since products are fully visible at all times. A limitation worth mentioning is that carton flows are not well suited for larger volume or full case applications. \nRestocking and picking typically offer the greatest opportunity for improving efficiency within order-picking operations. With carton flow rack systems, labor savings of up to 75% can be realized almost immediately. Because items are picked from the front and stocked from the rear, both functions can be performed without interference and with minimized travel.\nIn a static storage system such as standard shelving, stockers and pickers often do a lot of unnecessary travel.\nHistory.\nLansing Peter Shield, President of Grand Union Co., applied for patents for the original gravity-feed rear-load design using Unistrut and Nylon strips in 1945 (later approved in 1948). The unit consisted of several inclined runways. The device was driven by gravity. A stockman would place merchandise in the rear of each runway and, as a shopper selected an item, the item behind it would slide forward in place of the previous one.\nGrand Union formed a company called Food-O-Mat to sell the carton flow system, and made Gardner Hinckley the president. Gauer Metal Products, Inc manufactured the carton flow units for Grand Union/Food-O-Mat. When Lansing Shield died of a heart attack, Thomas Butler was appointed the new president. Butler had no interest in continuing to use carton flow units in Grand Union supermarkets, so Food-O-Mat went off on its own to sell the product with Gauer Metal Products as its manufacturer.\nCarton flow today.\nThe carton flow design has gone through countless changes over the years, and has now evolved to full shelving units. These units consist of polyethylene or aluminum roller runways and can be stand-alone racks or can be installed into pallet racks. Conveyor systems are sometimes used as an alternative option to carton flow shelving.", "Engineering,_Manufacturing": 0.9998586178, "qwen": "Yes"}
{"id": "12691300", "revid": "55327", "url": "https://en.wikipedia.org/wiki?curid=12691300", "title": "Duplex worm", "text": "A duplex worm or dual lead worm is a worm gear set where the two flanks are manufactured with slightly different modules and/or diameter quotients. As a result of this, different lead angles on both tooth profiles are obtained, so that the tooth thickness is continuously increasing all over the worm length, while the gap between two threads is decreasing. This allows control of backlash.\nAt the worm wheel, the different modules result in different addendum modification coefficients and rolling circle diameters at both flanks. Because of this the profiles are different at the front and at the rear flank. The thickness of each tooth and the tooth gaps remain constant at the circumference of the wheel. \nBacklash adjustment is done by shifting the worm axially, so that the section of the worm with the needed tooth thickness will be in contact with the wheel, giving the desired backlash (fig. 1). \nThis way, backlash can be easily adjusted to any desired value when mounting the gear, and even worn gears can be readjusted at any time delicately and continuously, without modifying the tooth contact or creating meshing interference.\nOther possibilities of backlash adjustment.\nBesides the above explained duplex method, there are various possibilities to adjust the backlash of worm gears: \nHowever all these methods demonstrate substantial disadvantages: \nDuplex gearings do not create these kind of problems.\nThey permit an always geometrically accurate teeth contact and beyond that, very delicate backlash adjustment. Neither the evolved contact area, the load-carrying capacity nor the actual efficiency are affected. In addition as duplex teeth are executed as involute gear they are insensitive in regards to modifications of the center distance, e.g. caused by worm shaft deflections.\nSetting of backlash.\nInstalling and resetting of a duplex worm wheelset is typically done as follows:\nApplications.\nDuplex gears are mainly utilized where any backlash is unwanted or can be harmful, to maintain repeated high precision positioning in both directions, to prevent impulse loaded damage, and when the contact flanks are alternating. Common applications include: rotary and tilting tables, milling machines, and presses.", "Engineering,_Manufacturing": 0.9999763966, "qwen": "Yes"}
{"id": "71744488", "revid": "869314", "url": "https://en.wikipedia.org/wiki?curid=71744488", "title": "2022–23 Albanian Cup", "text": "2022–23 Albanian Cup  was the seventy-first season of Albania's annual cup competition, the Albanian Cup. Egnatia won the cup, their first title in the competition.\nFormat.\nTies are played in a two-legged format similar to those of European competitions. If the aggregate score is tied after both games, the match is decided by extra time and a penalty shoot-out, if necessary.\nPreliminary round.\nIn order to reduce the number of participating teams for the first round to 32, a preliminary tournament is played. In contrast to the main tournament, the preliminary tournament is held as a single-leg knock-out competition. The matches were played on 15 September 2022.\nVeleçiku advanced to the first round.\nDevolli advanced to the first round.\nFirst round.\nAll 26 eligible teams of the 2022–23 Kategoria Superiore and 2022–23 Kategoria e Parë will enter in this round along with 8 teams from Kategoria e Dytë. The matches were played on 25, 26, 28 September 2022 as well as 11 and 12 October 2022.\nTirana advanced to the second round.\nPartizani advanced to the second round.\nVllaznia advanced to the second round.\nKastrioti advanced to the second round.\nDinamo Tirana advanced to the second round.\nBylis advanced to the second round.\nKorabi advanced to the second round.\nLushnja advanced to the second round.\nLaçi advanced to the second round.\nKukësi advanced to the second round.\nTeuta advanced to the second round.\nEgnatia advanced to the second round.\nSkënderbeu advanced to the second round.\nErzeni advanced to the second round.\nApolonia advanced to the second round.\nTomori advanced to the second round.\nSecond round.\nAll the 16 qualified teams from the first round progressed to the second round. The first legs were played on 17 and 18 January 2023 while the second legs took place on 2 and 3 February 2023.\nTirana advanced to the quarter finals.\nPartizani advanced to the quarter finals.\nVllaznia advanced to the quarter finals.\nKastrioti advanced to the quarter finals.\nLaçi advanced to the quarter finals.\nKukësi advanced to the quarter finals.\nTeuta advanced to the quarter finals.\nEgnatia advanced to the quarter finals.\nQuarter-finals.\nAll eight qualified teams from the second round progressed to the quarter-finals. The first legs were played on 28 February and 1 March 2023 while the second legs took place on 14 and 15 March 2023.\nTirana advanced to the semi finals.\nVllaznia advanced to the semi finals.\nEgnatia advanced to the semi finals.\nTeuta advanced to the semi finals.\nSemi-finals.\nThe first legs were played on 26 April while the second legs took place on 10 May 2023.\nEgnatia advanced to the final.\nTirana advanced to the final.", "Engineering,_Manufacturing": 0.9954773188, "qwen": "Yes"}
{"id": "11731664", "revid": "44530844", "url": "https://en.wikipedia.org/wiki?curid=11731664", "title": "Vacuum arc remelting", "text": "Vacuum arc remelting (VAR) is a secondary melting process for production of metal ingots with elevated chemical and mechanical homogeneity for highly demanding applications. The VAR process has revolutionized the specialty traditional metallurgical techniques industry, and has made possible tightly-controlled materials used in biomedical, aviation and aerospace.\nOverview.\nVAR is used most frequently in high value applications. It is an additional processing step to improve the quality of metal. Because it is time consuming and expensive, a majority of commercial alloys do not employ the process. Nickel, titanium, and specialty steels are materials most often processed with this method. The conventional path for production of titanium alloys includes single, double or even triple VAR processing. Use of this technique over traditional methods presents several advantages:\nProcess description.\nThe alloy to undergo VAR is formed into a cylinder typically by vacuum induction melting (VIM) or ladle refining (airmelt). This cylinder, referred to as an electrode is then put into a large cylindrical enclosed crucible and brought to a metallurgical vacuum . At the bottom of the crucible is a small amount of the alloy to be remelted, which the top electrode is brought close to prior to starting the melt. Several kiloamperes of DC current are used to start an arc between the two pieces, thus a continuous melt is derived. The crucible (typically made of copper) is surrounded by a water jacket to cool the melt and control the solidification rate. To prevent arcing between the electrode and the crucible walls, the diameter of the crucible is larger than the electrode. As a result, the electrode must be lowered as the melt consumes it. Control of the current, cooling water, and electrode gap is essential to effective control of the process and production of defect-free material.\nIdeally, the melt rate stays constant throughout the process cycle, but monitoring and control of the vacuum arc remelting process is not simple. This is because there is a complex heat transfer occurring involving conduction, radiation, convection within the liquid metal, and advection caused by the Lorentz force. Ensuring the consistency of the melt process in terms of pool geometry, and melt rate is crucial in ensuring the best possible properties of the alloy.\nMaterials and applications.\nThe VAR process is used on many different materials. Certain applications almost always use a material that has been VAR treated. A list of materials that may be VAR treated include:\nNote that pure titanium and most titanium alloys are double or triple VAR processed. Nickel-based super alloys for aerospace applications are usually VAR processed. Zirconium and niobium alloys used in the nuclear industry are routinely VAR processed. Pure platinum, tantalum, and rhodium may be VAR processed.", "Engineering,_Manufacturing": 0.999973774, "qwen": "Yes"}
{"id": "22274918", "revid": "2051880", "url": "https://en.wikipedia.org/wiki?curid=22274918", "title": "Optical interconnect", "text": "In integrated circuits, optical interconnects refers to any system of transmitting signals from one part of an integrated circuit to another using light. Optical interconnects have been the topic of study due to the high latency and power consumption incurred by conventional metal interconnects in transmitting electrical signals over long distances, such as in interconnects classed as \"global interconnects\". The International Technology Roadmap for Semiconductors (ITRS) has highlighted interconnect scaling as a problem for the semiconductor industry.\nIn electrical interconnects, nonlinear signals (e.g. digital signals) are transmitted by copper wires conventionally, and these electrical wires all have resistance and capacitance which severely limits the rise time of signals when the dimension of the wires are scaled down. Optical solution are used to transmit signals through long distances to substitute interconnection between dies within the integrated circuit (IC) package. \nIn order to control the optical signals inside the small IC package properly, microelectromechanical system (MEMS) technology can be used to integrate the optical components (i.e. optical waveguides, optical fibers, lens, mirrors, optical actuators, optical sensors etc.) and the electronic parts together effectively.\nProblems of the current interconnect in the package.\nConventional physical metal wires possess both resistance and capacitance, limiting the rise time of signals. Bits of information will overlap with each other when the frequency of signal is increased to a certain level.\nBenefits of using optical interconnection.\nOptical interconnections can provide benefits over conventional metal wires which include:\nChallenges for optical interconnect.\nHowever, there are still many technical challenges in implementing dense optical interconnects to silicon CMOS chips. These challenges are listed as below: ", "Engineering,_Manufacturing": 0.9999791384, "qwen": "Yes"}
{"id": "22282608", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=22282608", "title": "Multi-leaded power package", "text": " The multi-leaded power package is a style of electronic component package, commonly used for high power integrated circuits, especially for monolithic audio amplifiers. It was derived from single in-line package. The difference is the lead arrangement; multi-leaded power packages usually have the lead bent to zig-zag pattern. Multi-leaded power packages commonly have more than three leads; nine-, thirteen- and fifteen-lead units are common, units with five or seven leads with TO-220 style are also manufactured. A notable characteristic is a metal tab with a hole, used in mounting the case to a heatsink. The physical view of multi-leaded power packages are simply stretched TO-220 packages. Components made in multi-leaded power packages can handle more power than those constructed in TO-220 cases, or even TO3 cases with thermal resistance no less than 1.5 C/W.\nOne well-known STMicroelectronics brand of this type of package is Multiwatt.\nTypical applications.\nMulti-leaded power packages are heatsinkable, and thus can be used in projects where a large amount of power is being drawn. The top of the package has a metal tab with a hole used in mounting the component to a heatsink. Thermal compound is also used to provide greater heat transfer.\nThe metal tab is often connected electrically to the internal circuitry, ground and supply connection are common. This does not normally pose a problem when using isolated heatsinks, but an electrically-insulating pad or sheet may be required to electrically isolate the component from the heatsink if the heatsink is grounded or otherwise non-isolated. The material used to electrically isolate the multi-leaded power package, like mica, needs to have a high thermal conductivity.\nIn applications where vertical clearance is at a premium (such as ISA cards in computers), it is often feasible to bend the leads at a right angle and mount the component flat to the printed wiring board using a screw and nut. This often provides enough surface area to heatsink the component when power dissipation is moderately high.", "Engineering,_Manufacturing": 1.0000027418, "qwen": "Yes"}
{"id": "1145328", "revid": "45710349", "url": "https://en.wikipedia.org/wiki?curid=1145328", "title": "Metal fabrication", "text": "Metal fabrication is the creation of metal structures by cutting, bending and assembling processes. It is a value-added process involving the creation of machines, parts, and structures from various raw materials. \nTypically, a fabrication shop bids on a job, usually based on engineering drawings, and if awarded the contract, builds the product. Large fab shops employ a multitude of value-added processes, including welding, cutting, forming and machining. \nAs with other manufacturing processes, both human labor and automation are commonly used. A fabricated product may be called a \"fabrication\", and shops specializing in this type of work are called \"fab shops\". The end products of other common types of metalworking, such as machining, metal stamping, forging, and casting, may be similar in shape and function, but those processes are not classified as fabrication.\nProcesses.\nFabrication comprises or overlaps with various metalworking specialties:\nRaw materials.\nStandard metal fabrication materials are:\nCutting and burning.\nA variety of tools are used to cut raw material. The most common cutting method is shearing.\nSpecial band saws for cutting metal have hardened blades and feed mechanisms for even cutting. Abrasive cut-off saws, also known as chop saws, are similar to miter saws but have a steel-cutting abrasive disks. Cutting torches can cut large sections of steel with little effort.\nBurn tables are CNC (computer-operated) cutting torches, usually powered by natural gas. Plasma and laser cutting tables, and water jet cutters, are also common. Plate steel is loaded on the table and the parts are cut out as programmed. The support table consists of a grid of bars that can be replaced when worn. Higher-end burn tables may include CNC punch capability using a carousel of punches and taps. In fabrication of structural steel by plasma and laser cutting, robots move the cutting head in three dimensions around the cut material.\nForming.\nForming converts flat sheet metal into 3-D parts by applying force without adding or removing material. The force must be great enough to change the metal's initial shape. Forming can be controlled with tools such as punches and dies. Machinery can regulate force magnitude and direction. Machine-based forming can combine forming and welding to produce lengths of fabricated sheeting (e.g. linear grating for water drainage). Most metallic materials, being at least somewhat ductile and capable of considerable permanent deformation without cracking or breaking, lend themselves particularly well to these techniques.\nProper design and use of tools with machinery creates a repeatable form that can be used to create products for many industries, including jewelry, aerospace, automotive, construction, civil and architectural.\nMachining.\nMachining is a specialized trade of removing material from a block of metal to make it a desired shape. Fab shops generally have some machining capability, using metal lathes, mills, drills, and other portable machining tools. Most solid components, such as gears, bolts, screws and nuts, are machined.\nWelding.\nWelding is the main focus of steel fabrication. Formed and machined parts are assembled and tack-welded in place, then rechecked for accuracy. If multiple weldments have been ordered, a fixture may be used to locate parts for welding. A welder then finishes the work according to engineering drawings (for detailed welding) or by their own experience and judgement (if no details are provided).\nSpecial measures may be needed to prevent or correct warping of weldments due to heat. These may include redesigning the piece to require less welding, employing staggered welding, using a stout fixture, covering the weldment in sand as it cools, and post-weld straightening.\nStraightening of warped steel weldments is done with an oxyacetylene torch. In this highly specialized work, heat is selectively applied to the steel in a slow, linear sweep, causing the steel to contract in the direction of the sweep as it cools. A highly skilled welder can remove significant warpage this way.\nSteel weldments are occasionally annealed in a low-temperature oven to relieve residual stresses. Such weldments, particularly those for engine blocks, may be line-bored after heat treatment.\nAfter the weldment has cooled, seams are usually ground clean, and the assembly can be sandblasted, primed and painted. Any additional manufacturing is then performed, and the finished product is inspected and shipped.\nSpecialties.\nMany fabrication shops offer specialty processes, including :", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "1145863", "revid": "46403608", "url": "https://en.wikipedia.org/wiki?curid=1145863", "title": "Thermoforming", "text": "Thermoforming is a manufacturing process where a plastic sheet is heated to a pliable forming temperature, formed to a specific shape in a mold, and trimmed to create a usable product. The sheet, or \"film\" when referring to thinner gauges and certain material types, is heated in an oven to a high-enough temperature that permits it to be stretched into or onto a mold and cooled to a finished shape. Its simplified version is vacuum forming.\nIn its simplest form, a small tabletop or lab size machine can be used to heat small cut sections of plastic sheet and stretch it over a mold using vacuum. This method is often used for sample and prototype parts. In complex and high-volume applications, very large production machines are utilized to heat and form the plastic sheet and trim the formed parts from the sheet in a continuous high-speed process and can produce many thousands of finished parts per hour depending on the machine and mold size and the size of the parts being formed.\nThermoforming differs from injection molding, blow molding, rotational molding and other forms of processing plastics. Thin-gauge thermoforming is primarily the manufacture of disposable cups, containers, lids, trays, blisters, clamshells, and other products for the food, medical, and general retail industries. Thick-gauge thermoforming includes parts as diverse as vehicle door and dash panels, refrigerator liners, utility vehicle beds and plastic pallets.\nMost thermoforming companies recycle their scrap and waste plastic, either by compressing in a baling machine or by feeding into a granulator (grinder) and producing ground flake, for sale to reprocessing companies or re-use in their own facility. Frequently, scrap and waste plastic from the thermoforming process is converted back into extruded sheet for forming again.\nProcedure.\nIn the most common method of high-volume, continuous thermoforming of thin-gauge products, plastic sheet is fed from a roll or from an extruder into a set of indexing chains that incorporate pins, or spikes, that pierce the sheet and transport it through an oven for heating to forming temperature. The heated sheet then indexes into a form station where a mating mold and pressure-box close on the sheet, with vacuum then applied to remove trapped air and to pull the material into or onto the mold along with pressurized air to form the plastic to the detailed shape of the mold. (Plug-assists are typically used in addition to vacuum in the case of taller, deeper-draw formed parts in order to provide the needed material distribution and thicknesses in the finished parts.) After a short form cycle, a burst of reverse air pressure is actuated from the vacuum side of the mold as the form tooling opens, commonly referred to as air-eject, to break the vacuum and assist the formed parts off of, or out of, the mold. A stripper plate may also be utilized on the mold as it opens for ejection of more detailed parts or those with negative-draft, undercut areas. The sheet containing the formed parts then indexes into a trim station on the same machine, where a die cuts the parts from the remaining sheet web or indexes into a separate trim press where the formed parts are trimmed. The sheet web remaining after the formed parts are trimmed is typically wound onto a take-up reel or fed into an inline granulator for recycling.\nDevelopments.\nMicroprocessor and computer controls on more modern machinery allow for greatly increased process control and repeatability of same-job setups from one production run with the ability to save oven heater and process timing settings between jobs. The ability to place formed sheets into an inline trim station for more precise trim registration has been improved due to the common use of electric servo motors for chain indexing versus air cylinders, gear racks, and clutches on older machines. Electric servo motors are also used on some modern and more sophisticated forming machines for actuation of the machine platens where form and trim tooling are mounted, rather than air cylinders which have traditionally been the industry standard, giving more precise control over closing and opening speeds and timing of the tooling. Quartz and radiant-panel oven heaters generally provide more precise and thorough sheet heating over older cal-rod type heaters, and better allow for zoning of ovens into areas of adjustable heat.\nA new technology, ToolVu, has been developed to provide real-time feedback on thermoformer machines. This stand-alone system connects directly to the thermoformer and utilizes multiple sensors to record production-run data in real time including air pressure, temperature, tool strain gauge and other specifications. The system sends out multiple warnings and alerts whenever pre-set production parameters are compromised during a run. This reduces machine down time, lowers startup time and decreases startup scrap.\nAn integral part of the thermoforming process is the tooling, which is specific to each part that is to be produced. Thin-gauge thermoforming as described above is almost always performed on in-line machines and typically requires molds, plug assists, pressure boxes and all mounting plates as well as the trim tooling and stacker parts that pertain to the job. Thick or heavy-gauge thermoforming also requires tooling specific to each part, but because the part size can be very large, the molds can be cast aluminum or some other composite material as well as machined aluminum as in thin gauge. Typically, thick-gauge parts must be trimmed on CNC routers or hand trimmed using saws or hand routers. Even the most sophisticated thermoforming machine is limited to the quality of the tooling. Some large thermoforming manufacturers choose to have design and tool making facilities in house while others will rely on outside tool-making shops to build the tooling.\nThin-gauge and heavy-gauge (thick) thermoforming.\nThere are two general thermoforming process categories. Sheet thickness less than 1.5 mm (0.060 inches) is usually delivered to the thermoforming machine from rolls or from a sheet extruder. Thin-gauge roll-fed or inline extruded thermoforming applications are dominated by rigid or semi-rigid disposable packaging. Sheet thicknesses greater than 3 mm (0.120 inches) are usually delivered to the forming machine by hand or an auto-feed method already cut to final dimensions. Heavy, or thick-gauge, cut sheet thermoforming applications are primarily used as permanent structural components. There is a small but growing medium-gauge market that forms sheet 1.5 mm to 3 mm in thickness.\nHeavy-gauge forming utilizes the same basic process as continuous thin-gauge sheet forming, typically draping the heated plastic sheet over a mold. Many heavy-gauge forming applications use vacuum only in the form process, although some use two halves of mating form tooling and include air pressure to help form. Aircraft windscreens and machine gun turret windows spurred the advance of heavy-gauge forming technology during World War II. Heavy-gauge parts are used as cosmetic surfaces on permanent structures such as kiosks, automobiles, trucks, medical equipment, material handling equipment, refrigerators, spas, and shower enclosures, and electrical and electronic equipment. Unlike most thin-gauge thermoformed parts, heavy-gauge parts are often hand-worked after forming for trimming to final shape or for additional drilling, cutting, or finishing, depending on the product. Heavy-gauge products typically are of a \"permanent\" end use nature, while thin-gauge parts are more often designed to be disposable or recyclable and are primarily used to package or contain a food item or product. Heavy-gauge thermoforming is typically used for production quantities of 250 to 3000 annually, with lower tooling costs and faster product development than competing plastic technologies like injection molding.\nOlimunllum CF/PEEK is obtained by thick gauge thermoforming of thin layers of previously impregnated fibers to form fully consolidated sheets. The main difference from custom-made composite plates lies in the standardized orientation of the reinforcing fibers, the standardized weight content of the polymer and standardized sheet thicknesses. This allows easy design and post-processing using identical or similar tools as commonly used when working with metallic light-weight materials like aluminium, titanium and steel.\nIndustry.\nThe more than US$10 billion North American market has traditionally been thin gauge and heavy gauge. In 2003 there were about 150 thin-gauge thermoformers in North America. Sixty percent formed proprietary products. Thirty percent were custom formers and 10 percent were OEMs with in-house forming capability. There were nearly a dozen thin-gauge formers having annual sales of at least $100 million. The largest had annual sales in excess of $1,000 million. There were about 250 heavy-gauge formers in North America. Nearly all were custom formers. Only two or three heavy-gauge formers had annual sales of more than $100 million. The largest had annual sales of about $140 million. Beaverton, Michigan, is known as the Plastic Thermoforming capital of the world fueled by the proximity of Dow Chemical Company of Midland, Michigan.", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "1145865", "revid": "1094053362", "url": "https://en.wikipedia.org/wiki?curid=1145865", "title": "Vacuum forming", "text": "Vacuum forming is a simplified version of thermoforming, where a sheet of plastic (in various forms HIPS (High impact polystyrene) for low impact products, or for Bathroom shower trays ABS, and exterior vehicle parts HDPE, plus various other types of vacuum formable materials) is heated to a forming temperature, stretched onto a single-surface mould, and forced against the mould by a vacuum. This process can be used to form plastic into permanent objects such as turnpike signs and protective covers. Normally draft angles are present in the design of the mould (a recommended minimum of 3°) to ease removal of the formed plastic part from the mould.\nRelatively deep parts can be formed if the formable sheet is mechanically or pneumatically stretched prior to bringing it into contact with the mold surface and applying the vacuum.\nSuitable materials for use in vacuum forming are conventionally thermoplastics. The most common and easiest to use thermoplastic is \"high impact polystyrene sheeting\" (HIPS). This is molded around a wood, structural foam or cast or machined aluminium mold, and can form to almost any shape. This high impact material is hygienic and capable of retaining heat and its shape when warm water is applied and is commonly used to package taste and odor sensitive products. Vacuum forming is also appropriate for transparent materials such as acrylic, which are widely used in applications for aerospace such as passenger cabin window canopies for military fixed wing aircraft and compartments for rotary wing aircraft. Vacuum forming is often used in low-level technology classes for an easy way to mold.\nModern vacuum-forming equipment is based on a series of US patents awarded in 1950, 1964, and 1974.\nTypical applications.\nOriginal equipment manufacturers (OEMs) utilize heavy gauge vacuum formed components for production quantities in the range of 250–3000 units per year. Vacuum-formed components can be used in place of complex fabricated sheet metal, fiberglass, or plastic injection molding. Typical industry examples besides product packaging include: fascias for outdoor kiosks and automated teller machines, enclosures for medical imaging and diagnostic equipment, engine covers in a truck cab or for construction equipment, and railcar interior trim and seat components. Vacuum formers are also often used by hobbyists, for applications such as masks and remote control cars.\nCommon problems.\nThere are some problems encountered in the vacuum forming process. Absorbed moisture can expand, forming bubbles within the plastic's inner layers. This significantly weakens the plastic. However, this can be solved by drying the plastic for an extended period at high but sub-melting temperature. Webs can form around the mold, which is due to overheating the plastic and so must be carefully monitored. Webbing can also occur when a mold is too large or parts of the mold are too close together. Finally, objects that are formed often stick to the mold, which is remedied by using a draft angle of three degrees or more in the mold.\nTypes of molds.\nThere are numerous patterns one can make with vacuum forming. The most inventive way to use vacuum forming is to take any small item, replicate it many times and then vacuum form the new pattern to create a more cohesive form. The vacuum forming helps tie the individual pieces together and make one mold out of many pieces that can easily be replicated. From there plaster, concrete, etc. can be cast into the plastic form.\nWood patterns are a common material to vacuum form as it is relatively inexpensive and allows the customer to make changes to the design easily. The number of samples that one is able to get from any pattern depends on the size of the part and the thickness of the material. Once the specifications of the part have been met, the pattern is then used to create a ceramic composite mold, or cast aluminum mold for regular production. Potentially, there are ways to create holes in plaster with a vacuum form if the replicated forms made from the vacuum form are deep enough and gaps are left between them for the plastic to form into. Then, once the plastic is used to cast a plaster mold, the deep plastic areas will leave holes if the mold is not completely filled.\nCast aluminium molds are cast at a foundry and typically have temperature control lines running through them. This helps to set the heat of the plastic being formed as well as speed up the fabrication process. Aluminium molds can be male or female in nature, and can also be used in pressure forming applications. The main drawback with this type of mold is the cost.\nMachined aluminium molds are like cast aluminium, but are cut out of a solid block of aluminium using a CNC machine and a CAD program. Typically, machined aluminium is used for shallow draw parts out of thin gauge material. Applications may include packaging and trays. Cost is a significant factor with this type of tooling.\nComposite molds are a lower cost alternative to cast or machined aluminium molds. Composite molds are typically made from filled resins that start as a liquid and harden with time. Depending on the application, composite molds can last a very long time and produce high quality parts.\nFinishing methods.\nOnce a vacuum forming has been created out of a sheet of plastic, a finishing operation will be needed in most cases to turn it into a usable product. Common vacuum forming finishing methods include:", "Engineering,_Manufacturing": 0.9999848604, "qwen": "Yes"}
{"id": "1149674", "revid": "34738792", "url": "https://en.wikipedia.org/wiki?curid=1149674", "title": "Knurling", "text": "Knurling is a manufacturing process, typically conducted on a lathe, whereby a pattern of straight, angled or crossed lines is rolled into the material.\nEtymology.\nThe terms \"knurl\" and \"knurled\" are from an earlier \"knur\" ‘knot in wood’ and the diminutive \"-le\", from Middle English \"knaur\" or \"knarre\" ‘knot in wood; twisted rock; crag’. This descends from Old English \"cnearra\" but the vowel in Middle English may have been influenced by Old Norse \"knǫrr\" ‘merchant ship’ which was known as \"cnearr\" in Old English. The modern \"gnarl\" is a back-formation of \"gnarled\" which itself is first attested in Shakespeare’s works and is apparently a variant of \"knurled\".\nUses.\nThe operation is performed for producing indentations on a part of a workpiece. Knurling allows hands or fingers to get a better grip on the knurled object than would be provided by the originally smooth metal surface. Occasionally, the knurled pattern is a series of straight ridges or a helix of \"straight\" ridges rather than the more-usual criss-cross pattern.\nKnurling may also be used as a repair method: because a rolled-in knurled surface has raised areas surrounding the depressed areas, these raised areas can make up for wear on the part. In the days when labor was cheap and parts expensive, this repair method was feasible on pistons of internal combustion engines, where the skirt of a worn piston was expanded to the nominal size using a knurling process. As auto parts have become less expensive, knurling has become less prevalent than it once was, and is specifically discouraged by performance engine builders.\nKnurling can also be used when a component will be assembled into a low precision component, for example a metal pin into a plastic molding. The outer surface of the metal pin is knurled so that the raised detail \"bites\" into the plastic irrespective of whether the size of the hole in the plastic closely matches the diameter of the pin.\nTool handles, mechanical pencils, the grips of pistols, barbell bars, the clamping surface of a motorcycle handlebar and the control knobs on electronic equipment are frequently knurled. Knurling is also used on the grips of darts and the footpegs of BMX bicycles. Knurling is also found in many surgical instruments, where it is used for instrument identification, and its ease of being brushed clean.\nProcess.\nMore common than knurl cutting, \"knurl rolling\" is usually accomplished using one or more very hard rollers that contain the reverse of the pattern to be imposed. It is possible for a \"straight\" knurl (not criss-crossed) to be pressed with a single roller, however the material needs to be supported adequately to avoid deformation. A criss-cross pattern can be accomplished using any of:\nUse stock with a circumference that's a multiple of the circular pitch, or stock with a diameter of the circular pitch over π. Blank diameter is critical to quality knurling. The wrong blank diameter can cause the knurl(s) to double track, giving a pattern finer than the knurl was designed to produce, one that is generally unsatisfactory. Picking the correct stock diameter is very similar to having two gears of the same diametrical pitch that fit together. Every time you add a tooth, the diameter increases by a discrete amount. There are no in-between diameters that work correctly. The same is true of knurls and the blank to be knurled, though fortunately knurls do tolerate a certain amount of error before problems occur. The integer number of knurls for any given diameter typically varies by three repetitions from the bottom to the top of the pattern. By comparison, for cut knurls, the spacing of the cuts is not preset and can be adjusted to allow an integral number of patterns around the workpiece no matter what the diameter of the workpiece.\nHand knurling tools are available. These resemble pipecutters but contain knurling wheels rather than cutting wheels. Usually, three wheels are carried by the tool: two left-handed wheels and one right-handed wheel or vice versa.\nCut knurling often employs automatic feed. The tooling for cut knurling resembles that for rolled knurling, with the exception that the knurls have sharp edges and are presented to the work at an angle allowing the sharp edges to cut the work. Angled, diamond and straight knurling are all supported by cut knurling. It is impossible to cut knurling \"Like extremely coarse pitch threads\" both because lathe gear trains will not support such longitudinal speeds and because reasonable cutting speeds would be impossible to achieve.", "Engineering,_Manufacturing": 0.9977202415, "qwen": "Yes"}
{"id": "15230235", "revid": "42676810", "url": "https://en.wikipedia.org/wiki?curid=15230235", "title": "Material handling", "text": "Material handling involves short-distance movement within the confines of a building or between a building and a transportation vehicle. It uses a wide range of manual, semi-automated, and automated equipment and includes consideration of the protection, storage, and control of materials throughout their manufacturing, warehousing, distribution, consumption, and disposal. Material handling can be used to create \"time and place utility\" through the handling, storage, and control of waste, as distinct from manufacturing, which creates \"form utility\" by changing the shape, form, and makeup of material.\nRole.\nMaterial handling plays an important role in manufacturing and logistics. Almost every item of physical commerce has been transported on a conveyor or lift truck or another type of material handling equipment in manufacturing plants, warehouses, and retail stores. While material handling is usually required as part of every production worker's job, over 650,000 people in the U.S. work as dedicated \"material moving machine operators\" and have a median annual wage of $31,530 (May 2012). These operators use material handling equipment to transport various goods in a variety of industrial settings including moving construction materials around building sites or moving goods onto ships.\nDesign of material handling systems.\nMaterial handling is integral to the design of most production systems since the efficient flow of material between the activities of a production system is heavily dependent on the arrangement (or \"layout\") of the activities. If two activities are adjacent to each other, then material might easily be handed from one activity to another. If activities are in sequence, a conveyor can move the material at low cost. If activities are separated, more expensive industrial trucks or overhead conveyors are required for transport. The high cost of using an industrial truck for material transport is due to both the labor costs of the operator and the negative impact on the performance of a production system (e.g., increased work in process) when multiple units of material are combined into a single transfer batch in order to reduce the number of trips required for transport.\nThe unit load concept.\nA unit load is either a single unit of an item, or multiple units so arranged or restricted that they can be handled as a single unit and maintain their integrity. Although granular, liquid, and gaseous materials can be transported in bulk, they can also be contained into unit loads using bags, drums, and cylinders. Advantages of unit loads are that more items can be handled at the same time (thereby reducing the number of trips required, and potentially reducing handling costs, loading and unloading times, and product damage) and that it enables the use of standardized material handling equipment. Disadvantages of unit loads include the negative impact of batching on production system performance, and the cost of returning empty containers/pallets to their point of origin.\nIn-process handling.\nUnit loads can be used both for in-process handling and for distribution (receiving, storing, and shipping). Unit load design involves determining the type, size, weight, and configuration of the load; the equipment and method used to handle the load; and the methods of forming (or building) and breaking down the load. For in-process handling, unit loads should not be larger than the production batch size of parts in process. Large production batches (used to increase the utilization of bottleneck activities) can be split into smaller \"transfer batches\" for handling purposes, where each transfer batch contains one or more unit loads, and small unit loads can be combined into a larger transfer batch to allow more efficient transport.\nDistribution.\nSelecting a unit load size for distribution can be difficult because containers/pallets are usually available only in standard sizes and configurations; truck trailers, rail boxcars, and airplane cargo bays are limited in width, length, and height; and the number of feasible container/pallet sizes for a load may be limited due to the existing warehouse layout and storage rack configurations and customer package/carton size and retail store shelf restrictions. Also, the practical size of a unit load may be limited by the equipment and aisle space available and the need for safe material handling.\nHealth and safety.\nManual material handling work contributes to a large percentage of the over half a million cases of musculoskeletal disorders reported annually in the United States. Musculoskeletal disorders often involve strains and sprains to the lower back, shoulders, and upper limbs. They can result in protracted pain, disability, medical treatment, and financial stress for those afflicted with them, and employers often find themselves paying the bill, either directly or through workers’ compensation insurance, at the same time they must cope with the loss of the full capacity of their workers.\nScientific evidence shows that effective ergonomic interventions can lower the physical demands of MMH work tasks, thereby lowering the incidence and severity of the musculoskeletal injuries they can cause. Their potential for reducing injury related costs alone make ergonomic interventions a useful tool for improving a company’s productivity, product quality, and overall business competitiveness. But very often productivity gets an additional and solid shot in the arm when managers and workers take a fresh look at how best to use energy, equipment, and exertion to get the job done in the most efficient, effective, and effortless way possible. Planning that applies these principles can result in big wins for all concerned.\nTypes.\nManual handling.\nManual handling refers to the use of a worker’s hands to move individual containers by lifting, lowering, filling, emptying, or carrying them. It can expose workers to physical dangers that can lead to injuries: a large percentage of the over half a million cases of musculoskeletal disorders reported in the U.S. each year arise from manual handling, and often involve strains and sprains to a person's lower back, shoulders and upper limbs.\nErgonomic improvements can be used to modify manual handling tasks to reduce injury. These improvements can include reconfiguring the task and using positioning equipment like lift/tilt/turn tables, hoists, balancers, and manipulators to reduce reaching and bending. The NIOSH (National Institute for Occupational Safety and Health) 1991 Revised Lifting Equation can be used to evaluate manual lifting tasks. Under ideal circumstances, the maximum recommended weight for manual lifting to avoid back injuries is 51 lb (23.13 kg). Using the exact conditions of the lift (height, distance lifted, weight, position of weight relative to body, asymmetrical lifts, and objects that are difficult to grasp), six multipliers are used to reduce the maximum recommended weight for less than ideal lifting tasks.\nAutomated handling.\nWhenever technically and economically feasible, equipment can be used to reduce and sometimes replace the need to manually handle material. Most existing material handling equipment is only \"semi-automated\" because a human operator is needed for tasks like loading/unloading and driving that are difficult and/or too costly to fully automate. However, ongoing advances in sensing, machine intelligence, and robotics have made it possible to fully automate an increasing number of handling tasks. A rough guide to determine how much can be spent for automated equipment that would replace one material handler is to consider that, with benefits, the median moving machine operator costs a company $45,432 per year. Assuming a real interest rate of 1.7% and a service life of 5 years with no adoption/adaptation cost, no learning cost, no training cost, and no operating cost for equipment with no salvage value, a company should be willing to pay up to\nformula_1\nto purchase automated equipment to replace one worker. In many cases, automated equipment is not as flexible as a human operator, both with respect to not being able to do a particular task as well as a human and not being able to be as easily redeployed to do other tasks as needs change.", "Engineering,_Manufacturing": 0.9999943972, "qwen": "Yes"}
{"id": "15233875", "revid": "41840956", "url": "https://en.wikipedia.org/wiki?curid=15233875", "title": "Direct part marking", "text": "Direct part marking (DPM) is a process to permanently mark parts with product information including serial numbers, part numbers, date codes, and barcodes. This is done to allow the tracking of parts through the full life cycle.\nThe interpretation of 'permanent' often depends on the context the part is used. In the aerospace industry an aircraft part may be in service for over 30 years. Within telecom and computer industries the life cycle may only last a few years.\nDPM is often used by automotive, aerospace, and electronic manufacturers to facilitate a reliable identification of their parts. This can assist in data logging for safety, warranty issues and satisfy regulatory requirements. Also the United States Department of Defense demands a physical mark on tangible assets in conjunction with the Item Unique Identification.\nBarcode types.\nThere are many ways to encode an information to a machine-readable code. The preferred codes are the Data Matrix and the QR Code. Data Matrix is used by Motorola. It is also preferred by NASA to mark parts. In the automotive industries also the QR Code is used. This is founded in the fact that this code was initially developed by Denso Wave (a global automotive components manufacturer) for tracking parts in vehicle manufacturing.\nMarking methods.\nMethods to produce a permanent mark on parts are:\nOther methods like manual metal stamp, vibro-etch and embossing were not suitable to successfully apply micro size (1/32- to 15/64-inch square), high density machine-readable symbols.\nMarking method selection factors.\nThe marking method depends on a number of different factors:", "Engineering,_Manufacturing": 0.9999363422, "qwen": "Yes"}
{"id": "934383", "revid": "1093678146", "url": "https://en.wikipedia.org/wiki?curid=934383", "title": "Westfield SEight", "text": "The SEiGHT (pronounced variously as S-8 or 'Sayt') is a sports car manufactured as a kit or factory built vehicle by Westfield Sportscars. It is based on the familiar Lotus Seven concept, created by Colin Chapman, whose design philosophy was to strip a car design down to bare essentials for the ultimate in driving experiences. Bar a few visual differences, such as a bonnet bulge to house the large engine, it uses the same widebody chassis as the smaller engined SEi. All SEiGHTs are defined as such by the powerplant - a V8 engine. In kit form they were initially only available from the factory as a rolling chassis, unlike other Westfield kits which can be bought in component form. Later in their production run Westfield would allow the SEiGHT to be purchased in component form allowing customers to fully experience the build.\nWestfield ended production of the SEiGHT in December 2010.\nPowerplant.\nThe Rover V8 engine powerplant of the SEiGHT ranges from 3.5 litre units originally sourced from the Rover SD1 to bored and stroked 5.2 litre units. There are also 3.9 fuel injected versions, which are currently provided in the factory built vehicles and TVR Power engines of 4.2 litres. On the whole the V8 is a Rover unit, an alloy block which is lighter than the cast iron blocks of many V8s. One example has been built around an alloy version of the Chevrolet small block with a displacement of 6.6 litres.", "Engineering,_Manufacturing": 0.9999645948, "qwen": "Yes"}
{"id": "13642299", "revid": "1167055132", "url": "https://en.wikipedia.org/wiki?curid=13642299", "title": "Bead probe technology", "text": "Bead probe technology (BPT) is technique used to provide electrical access (called “nodal access”) to printed circuit board (PCB) circuitry for performing in-circuit testing (ICT). It makes use of small beads of solder placed onto the board's traces to allow measuring and controlling of the signals using a test probe. This permits test access to boards on which standard ICT test pads are not feasible due to space constraints.\nDescription.\nBead probe technology is a probing method used to connect electronic test equipment to the device under test (DUT) within a bed of nails fixture. The technique was first used in the 1990s and originally given the name “Waygood Bump” after one of the main proponents, Rex Waygood. They are also commonly referred to as solder bumps. Bead probes were designed for when less than 30 mil is available for test probe points on the PCB. They are used with standard ICT spring-loaded test probes to connect the test equipment to the DUT.\nBead construction.\nBead probes are made from a very small \"beads\" of solder that fit atop of the PCB traces. They are manufactured using the same techniques as other solder features. Construction requires a hole to be opened in the solder mask, exposing the copper trace. This hole is sized to precisely control the amount of metal that forms the bead. Solder paste is applied to the location and reflowed. During reflow, solder flows and is drawn to the copper trace. Surface tension causes the bead to have a curved surface and rise above the solder mask, where it solidifies into a Bead Probe. The bead will be roughly obround in shape and may be 15-25 mils long. A properly constructed bead is the same width as the trace and just enough to clear the surrounding solder mask. The bead is then accessible for testing using a probe with a flat end, which can help compensate for the tolerance build up in the test fixture and PCB.\nAdvantages.\nBead probe can be used in circuits where the pin-pitch is too fine to allow standard test pads. This is becoming more common as pin pitches continue to reduce, particularly in embedded devices. Typically bead probe widths are the width of the PCB traces with a length of about three times this. This allows a high degree of flexibility in their positioning, and can in some cases be applied retrospectively to existing layouts.\nBecause of their small size, bead probes do not affect the signal quality of the signals transferring within the PCB trace. This is especially useful in high speed input/output (HSIO) interconnects, where a standard test pad would interfere with the signal.", "Engineering,_Manufacturing": 1.0000052452, "qwen": "Yes"}
{"id": "32008772", "revid": "222758", "url": "https://en.wikipedia.org/wiki?curid=32008772", "title": "Redistribution layer", "text": "A redistribution layer (RDL) is an extra metal layer on an integrated circuit that makes its I/O pads available in other locations of the chip, for better access to the pads where necessary.\nWhen an integrated circuit is manufactured, it usually has a set of I/O pads that are wirebonded to the pins of the package. A redistribution layer is an extra layer of wiring on the chip that enables bond out from different locations on the chip, making chip-to-chip bonding simpler. Another example of the use for RDL is for spreading the contact points around the die so that solder balls can be applied, and the thermal stress of mounting can be spread.", "Engineering,_Manufacturing": 0.9999703169, "qwen": "Yes"}
{"id": "32010484", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=32010484", "title": "LARG SCM", "text": "LARG Supply Chain Management attempts to put together lean, agile, resilient, and green approaches in supply chain management. Lean supply chain managements aims are to maintain close to zero inventories and reduce work-in-process; Agile goes for quick responses to customer inquiries and market changes while controlling costs and quality; resilience is about reacting quickly to disruptions impacting supply chain; and green refers to sustainability in supply chain through low emissions to the environment and a recycling strategy for products.\nHistory.\nThe idea of LARG SCM was developed in the research unit of mechanical and industrial engineering (UNIDEMI) in the Faculty of Science and Technology at New University of Lisbon, Portugal. UNIDEMI is the main research center working on LARG SCM. UNINOVA and NECE are contributing partners.\nOverview.\nA lean company means nearly zero inventories; a resilient company must have enough inventory to react to the effects of disruptions that may occur in a supply chain. These concepts seem to be contradictory . However, it would be ideal to have both systems working together in a company. These facts advise for further research in production and supply chain management; lean and resilient concepts require to be modeled on a compatibility basis.\nLARG SCM develops a deep understanding of interrelationships (conflicts and trade-offs) across lean, agile, resilient and green supply chain paradigms. This understanding is believed to be vital to turn these concepts really compatible. This achievement will provide an important contribution for a competitive and sustainable environment; its justification will be based on better “lean, agile, resilient and green production systems” at the company level, with implications at the overall supply chain level and its agents.\nLARG SCM encompasses a variety of related topics such as methodology, characteristics, organizational system, Performance measurement, human factors, information system, and management integration model.", "Engineering,_Manufacturing": 0.9969301224, "qwen": "Yes"}
{"id": "32034050", "revid": "6246805", "url": "https://en.wikipedia.org/wiki?curid=32034050", "title": "Waterloo Manufacturing Company", "text": "The Waterloo Manufacturing Company, Ltd. was a Canadian farm engine builder based in Waterloo, Ontario, which built engines in sizes ranging from sixteen to thirty horsepower between 1880 and 1925.\nWaterloo Manufacturing of Ontario is occasionally confused with the Waterloo Gasoline Engine Company, of Waterloo, Iowa, U.S., which was purchased by John Deere for its popular Waterloo Boy Tractor. No relationship between the companies exists.\nHistory.\nIn the 1920s and 30's Waterloo Mfg served as Canadian distributors for many U.S.-built brands including Hart Parr, Rock Island Heider, Rock Island, Belle City, Twin Cities, Minneapolis-Moline.\nWaterloo Manufacturing continues to sell and service industrial boilers.", "Engineering,_Manufacturing": 0.9996974468, "qwen": "Yes"}
{"id": "32042462", "revid": "8024439", "url": "https://en.wikipedia.org/wiki?curid=32042462", "title": "Packsize", "text": "Packsize is an American corrugated material manufacturer and on-demand packaging system provider for businesses with complex corrugated packaging needs. The business is headquartered in Salt Lake City, Utah and has operations in United States, Canada, United Kingdom, Germany, and the Scandinavia . It serves customers in 21 countries.\nHistory.\nPacksize International LLC was founded in the USA in 2002. In 2007, Intermountain West investment firm Peterson Partners made a $4.6 million investment in Packsize. Packsize founder Hanko Kiessner received the Ernst & Young Entrepreneur of the Year Award 2008 in the Manufacturing/Distribution category in the Pacific Northwest. In 2020, Rod Gallaway was appointed CEO of Packsize. In September of 2022, the company added Greg Caldwell as its first Chief Marketing Officer.\nBusiness model.\nPacksize established Right-sized Packaging on Demand as its business model. Through this model, Packsize retains ownership of its technology giving the company a long-term stake in its customers’ packaging performance as well as continued revenue. p . T \nPacksize’s Right-sized Packaging on Demand business model includes using its On Demand Packaging system. Packsize coined the term On Demand Packaging to identify and distinguish its unique system from typical box systems. The On Demand Packaging system eliminates the need for large inventories of pre-ordered cardboard boxes and minimizes the amount of packaging filler needed, if any. Packsize’s On Demand Packaging system includes a box-making machine, software and corrugated material. Product dimensions are entered into the box-making machine. The machine cuts, creases and scores the corrugated material to the exact specifications to create a customized box specifically optimized for the product. As a result, less packaging material and void fill are required to safely package items. The On Demand Packaging system also reduces the space required for packaging material inventory and shipping costs.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "38562486", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=38562486", "title": "PTE technique", "text": "The Photothermoelectric (PTE) effect is based on the Seebeck effect, where the heating is achieved by absorbing light on a thermoelectric (TE) material. Synonymous to PPE technique for thermal characterization of materials, PTE can be used to thermally characterize both thermoelectrics (acts as sensor and sample) and other sample materials (while acting as a sensor).\nAn advantage of such sensors stems from their wide temperature range of applicability since pyromaterials are limited to its curie temperature. On the other hand, in order to obtain a useful signal from TE material, depends on its Seebeck coefficient, comparatively large amount of heat (light excitation) has to be deposited on the material. As far as now, Frequency domain PTE technique is in its preliminary stage for the thermal characterization of materials. Advances were done in liquid thermoelectrics as well on PTE. ", "Engineering,_Manufacturing": 1.0000085831, "qwen": "Yes"}
{"id": "38568991", "revid": "2051880", "url": "https://en.wikipedia.org/wiki?curid=38568991", "title": "Candace A. Yano", "text": "Candace A. Yano is Professor and Chair at Haas School of Business's Operations and Information Technology Management Group, and Professor and former Head of Department of Industrial Engineering & Operations Research, both at University of California, Berkeley. She is also a senior technical consultant on operations management issues for Yano Accountancy Corporation (YAC).\nAcademic work.\nYano is known for her work in Inventory Theory, Logistics Management, Supply Chain Management, Service Management, Production-Quality Interface Issues, and Marketing-Production Interface Issues, and serves or has served on the editorial board of IIE Transactions, Interfaces, Management Science, Manufacturing & Service Operations Management, Naval Research Logistics, Operations Research, and Productions and Operations Management.\nCareer.\nPrior to joining University of California, Berkeley, Yano was on the faculty at Department of Industrial & Operations Engineering, University of Michigan from 1983 to 1993, and served as a member of the technical staff at Bell Labs from 1981 to 1982.\nAwards.\nIn 2006, Yano was named a Fellow of Institute of Industrial Engineers (IIE). As one of the earliest female scholars in the field of Operations Research, Yano received 2008 WORMS Award for the Advancement of Women in OR/MS. She is a past President of the Technical Section on Manufacturing Management of ORSA—which has evolved to today's MSOM Society—and won the MSOM Society's first Distinguished Service Award in 1997.\nIn 2014, Yano was elected as an INFORMS Fellow in honor of her lifetime achievement in Operations Research and the Management Sciences and in recognition of her role as \"a leader in operations management research who has provided significant service to the field as program chair, editor, adviser, teacher, and mentor.\"\nIn 2018, Yano was awarded the George E. Kimball Medal in recognition of her service to INFORMS, and the field of Operations Research and Management Sciences.", "Engineering,_Manufacturing": 0.9972685575, "qwen": "Yes"}
{"id": "8699846", "revid": "5042921", "url": "https://en.wikipedia.org/wiki?curid=8699846", "title": "Gold–aluminium intermetallic", "text": "A gold–aluminium intermetallic is an intermetallic compound of gold and aluminium that occurs at contacts between the two metals. \nThese intermetallics have different properties from the individual metals, which can cause problems in wire bonding in microelectronics. The main compounds formed are Au5Al2 (white plague) and AuAl2 (purple plague), which both form at high temperatures. \nWhite plague is the name of the compound Au5Al2 as well as the problem it causes. It has low electrical conductivity, so its formation at the joint leads to an increase of electrical resistance which can lead to total failure. Purple plague (sometimes known as \"purple death\" or Roberts-Austen's \"purple gold\") is a brittle, bright-purple compound, AuAl2, or about 78.5% Au and 21.5% Al by mass. AuAl2 is the most stable thermally of the Au–Al intermetallic compounds, with a melting point of 1060°C (see phase diagram), similar to that of pure gold. The process of the growth of the intermetallic layers causes reduction in volume, and hence creates cavities in the metal near the interface between gold and aluminium.\nOther gold–aluminium intermetallics can cause problems as well. Below 624°C, purple plague is replaced by Au2Al, a tan-colored substance. It is a poor conductor and can cause electrical failure of the joint that can lead to mechanical failure. At lower temperatures, about 400–450°C, an interdiffusion process takes place at the junction. This leads to formation of layers of several intermetallic compounds with different compositions, from gold-rich to aluminium-rich, with different growth rates. Cavities form as the denser, faster-growing layers consume the slower-growing ones. This process, known as Kirkendall voiding, leads to both increased electrical resistance and mechanical weakening of the wire bond. When the voids are collected along the diffusion front, a process aided by contaminants present in the lattice, it is known as Horsting voiding, a process similar to and often confused with Kirkendall voiding.\nAll problems caused by gold–aluminium intermetallics can be prevented either by using bonding processes that avoid high temperatures (e.g. ultrasonic welding), or by designing circuitry in such a way as to avoid aluminium-to-gold contact using aluminium-to-aluminium or gold-to-gold junctions.", "Engineering,_Manufacturing": 0.999979496, "qwen": "Yes"}
{"id": "21921347", "revid": "19921271", "url": "https://en.wikipedia.org/wiki?curid=21921347", "title": "Virtual prototyping", "text": "Virtual prototyping is a method in the process of product development. It involves using computer-aided design (CAD), computer-automated design (CAutoD) and computer-aided engineering (CAE) software to validate a design before committing to making a physical prototype. This is done by creating (usually 3D) computer generated geometrical shapes (parts) and either combining them into an \"assembly\" and testing different mechanical motions, fit and function. The assembly or individual parts could be opened in CAE software to simulate the behavior of the product in the real world.\nBackground.\nThe product design and development process used to rely primarily on engineers' experience and judgment in producing an initial concept design. A physical prototype was then constructed and tested in order to evaluate its performance. Without any way to evaluate its performance in advance, the initial prototype was highly unlikely to meet expectations. Engineers usually had to re-design the initial concept multiple times to address weaknesses that were revealed in physical testing.\nMove towards virtual prototypes.\nToday, manufacturers are under pressure to reduce time to market and optimize products to higher levels of performance and reliability. A much higher number of products are being developed in the form of virtual prototypes in which engineering simulation software is used to predict performance prior to constructing physical prototypes. Engineers can quickly explore the performance of thousands of design alternatives without investing the time and money required to build physical prototypes. The ability to explore a wide range of design alternatives leads to improvements in performance and design quality. Yet the time required to bring the product to market is usually reduced substantially because virtual prototypes can be produced much faster than physical prototypes.\nEnd-to-end prototyping.\nEnd-to-end prototyping accounts fully for how a product or a component is manufactured and assembled, and it links the consequences of those processes to performance. Early availability of such physically realistic virtual prototypes allows testing and performance confirmation to take place as design decisions are made; enabling the acceleration of the design activity and providing more insight on the relationship between manufacturing and performance than can be achieved by building and testing physical prototypes. The benefits include reduced costs in both design and manufacturing as physical prototyping and testing is dramatically reduced/eliminated and lean but robust manufacturing processes are selected.\nEffects.\nThe research firm Aberdeen Group reports that best-in-class manufacturers, who make extensive use of simulation early in the design process, hit revenue, cost, and launch date and quality targets for 86% or more of their products. Best-in-class manufacturers of the most complex products get to market 158 days earlier with $1.9 million lower costs than all other manufacturers. Best-in-class manufacturers of the simplest products get to market 21 days earlier with $21,000 fewer product development costs.\nExamples.\nFisker Automotive used virtual prototyping to design the rear structure and other areas of its Karma plug-in hybrid to ensure the integrity of the fuel tank in a rear end crash as required for Federal Motor Vehicle Safety Standards (FMVSS) 301 certification. Agilent Technologies used virtual prototyping to design cooling systems for the calibration head for a new high-speed oscilloscope. Miele used virtual prototyping to improve the development of its washer-disinfector machines by simulating their operational characteristics early in the design cycle. Several CAE software solutions (for example, Working Model and SimWise) offer the possibility to check the benefits of virtual prototyping even for students and small companies, and collection of case studies are available since 1996.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1767373", "revid": "1161402389", "url": "https://en.wikipedia.org/wiki?curid=1767373", "title": "Hybrid III", "text": "The Hybrid III is the standard crash test dummy for frontal crash tests as of the beginning of the 21st century. It was initially only a 50th percentile male (equal in height and weight to the average North American male at the time of its development).\nHybrid III, the 50th percentile male dummy which made its first appearance in 1976, is the familiar crash test dummy. If he could stand upright, he would be 5' 9\" tall and would have a mass of approximately 78 kg (172 lb). He occupies the driver's seat in all the Insurance Institute for Highway Safety (IIHS) 65 km/h (40 mph) offset frontal crash tests. \nHybrid III has a \"big brother\" model, the 95th percentile Hybrid III, at 188 cm (6'2\") and 100 kg (223 lb). The 'female' Hybrid III is a 5th percentile dummy that is based on the same male body shape as the others, at a diminutive 152 cm (5 ft) tall and 50 kg (110 lb). The two Hybrid III child dummies represent a 21 kg (47 lb) six-year-old and a 15 kg (33 lb) three-year-old. The child models are recent additions to the crash test dummy family; because so little hard data are available on the effects of accidents on children, and such data are very difficult to obtain, these models are based in large part on estimates and approximations.\nExternal links.\nHeart 40", "Engineering,_Manufacturing": 0.9960746169, "qwen": "Yes"}
{"id": "6524650", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=6524650", "title": "Edible ink printing", "text": "Edible ink printing is the process of creating preprinted images with edible food colors onto various confectionery products such as cookies, cakes and pastries. Designs made with edible ink can be either preprinted or created with an edible ink printer, a specialty device which transfers an image onto a thin, edible paper. \nEdible paper is made of starches and sugars and printed with edible food colors. Some edible inks and paper materials have been approved by the Food and Drug Administration and carry its generally recognized as safe certification.\nPaper.\nThe first papers of this process used rice paper, while modern versions use frosting sheets. The first U.S. patent for food printing, as it applied to edible ink printing, was filed by George J. Krubert of the Keebler Company and granted in 1981. Such paper is eaten without harmful effects. Most edible paper has no significant flavor and limited texture. Edible paper may be printed on by a standard printer and, upon application to a moist surface, dissolves while maintaining a high resolution. The end effect is that the image (usually a photograph) on the paper appears to be printed on the icing.\nEdible inks.\nEdible printer inks have become prevalent and are used in conjunction with special ink printers. Ink that is not specifically marketed as being edible may be harmful or fatal if swallowed. Edible toner for laser printers is not currently available. Any inkjet or bubblejet printer can be used to print, although resolution may be poor, and care should be taken to avoid contaminating the edible inks with previously used inks. Inkjet or bubblejet printers can be converted to print using edible ink, and cartridges of edible ink are commercially available. It is always much safer to use a dedicated inkjet printer for edible ink printing.\nSome edible inks are powdered, but if they are easily soluble in water they can also be used as any other edible ink without reducing quality. Edible paper is used on cakes, cookies, cupcakes and marshmallows.", "Engineering,_Manufacturing": 0.8736125827, "qwen": "Yes"}
{"id": "6546396", "revid": "1190064", "url": "https://en.wikipedia.org/wiki?curid=6546396", "title": "Military supply-chain management", "text": "Military supply-chain management is a cross-functional approach to procuring, producing and delivering products and services for military materiel applications. Military supply chain management includes sub-suppliers, suppliers, internal information and funds flow.\nSupply.\nA supply is the procurement, distribution, maintenance while in storage, and salvage of supplies, including the determination of kind and quantity of supplies. The producer phase of a military supply extends from determination of procurement schedules to acceptance of finished supplies by the military services. The consumer phase of a military supply extends from receipt of finished supplies by the military services, through issue for use or consumption.\nSupply chain.\nThe supply chain is the linked activities associated with providing material from a raw material stage to an end user as a finished good. Supply control\nis the process by which an item of supply is controlled within the supply system, including requisitioning, receipt, storage, stock control, shipment, disposition, identification, and accounting. The supply point is a location where supplies, services and materials are located and issued. These locations are temporary and mobile, normally being occupied for up to 72 hours.\nLogistics.\nMilitary logistics is the science of planning and carrying out the movement and maintenance of armed forces. In its most comprehensive sense, those aspects of military operations that deal with: a. design and development, acquisition, storage, movement, distribution, maintenance, evacuation, and disposition of materiel; b. movement, evacuation, and hospitalization of personnel; c. acquisition or construction, maintenance, operation and disposition of facilities; and d. acquisition or furnishing of services.\nLogistics versus supply-chain management.\nThe major difference between the concept of logistic management and supply-chain management is the level of information gathered, processes, analysed and used for decision making. An SCM-based organization not only having concerns with its immediate clients but also handles and forecasts the factors affecting directly or indirectly their supplier or suppliers or on their client or clients. If we exclude this information part out of supply chain model then we can see the logistic management part of the business.\nLimitations of military supply chain.\nUnlike standard supply-chain management practices world-wide, some major concepts are not supported in the military domain. For example, the \"just-in-time\" (JIT) model emphasizes holding less (or no) inventory, whereas in military supply chains, due to the high costs of a stock-out (potentially placing lives in danger), keeping huge inventory is a more acceptable practice. Some examples of these are the ammunition dump and oil depot.\nLikewise, the military procurement process has much different criteria than the normal business procurement process. Military needs call for reliability of supply during peace and war, as compared to price and technology factors.", "Engineering,_Manufacturing": 0.9996260405, "qwen": "Yes"}
{"id": "13414189", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=13414189", "title": "Automated X-ray inspection", "text": "Automated inspection (AXI) is a technology based on the same principles as automated optical inspection (AOI). It uses as its source, instead of visible light, to automatically inspect features, which are typically hidden from view.\nAutomated X-ray inspection is used in a wide range of industries and applications, predominantly with two major goals:\nWhilst AOI is mainly associated with electronics manufacturing (due to widespread use in PCB manufacturing), AXI has a much wider range of applications. It ranges from the quality check of alloy wheels to the detection of bone fragments in processed meat. Wherever large numbers of very similar items are produced according to a defined standard, automatic inspection using advanced image processing and pattern recognition software (Computer vision) has become a useful tool to ensure quality and improve yield in processing and manufacturing.\nPrinciple of Operation.\nWhile optical inspection produces full color images of the surface of the object, x-ray inspection transmits x-rays through the object and records gray scale images of the shadows cast. The image is then processed by image processing software that detects the position and size/ shape of expected features (for process optimization) or presence/ absence of unexpected/ unintended objects or features (for anomaly detection). \nX-rays are generated by an x-ray tube, usually located directly above or below the object under inspection. A detector located the opposite side of the object records an image of the x-rays transmitted through the object. The detector either converts the x-rays first into visible light which is imaged by an optical camera, or detects directly using an x-ray sensor array. The object under inspection may be imaged at higher magnification by moving the object closer to the x-ray tube, or at lower magnification closer to the detector.\nSince the image is produced due to the different absorption of x-rays when passing through the object, it can reveal structures inside the object that are hidden from outside view.\nApplications.\nWith the advancement of image processing software the number applications for automated x-ray inspection is huge and constantly growing. The first applications started off in industries where the safety aspect of components demanded a careful inspection of each part produced (e.g. welding seams for metal parts in nuclear power stations) because the technology was expectedly very expensive in the beginning. But with wider adoption of the technology, prices came down significantly and opened automated x-ray inspection up to a much wider field- partially fueled again by safety aspects (e.g. detection of metal, glass or other materials in processed food) or to increase yield and optimize processing (e.g. detection of size and location of holes in cheese to optimize slicing patterns).\nIn mass production of complex items (e.g. in electronics manufacturing), an early detection of defects can drastically reduce overall cost, because it prevents defective parts from being used in subsequent manufacturing steps. This results in three major benefits: a) it provides feedback at the earliest possible state that materials are defective or process parameters got out of control, b) it prevents adding value to components that are already defective and therefore reduces the overall cost of a defect, and c) it increases the likelihood of field defects of the final product, because the defect may not be detected at later stages in quality inspection or during functional testing due to the limited set of test patterns.\nUse of AXI in the Food Industry.\nForeign body detection, fill level control, and process control are the three main areas for the use of AXI in the food industry. Especially in packaged goods at the end of the filling and packaging line the use of X-ray scanners has become the norm, rather than the exception. It is often used in combination with other QA measures, especially inline check weighers.\nMost of it is limited to a good/ bad check, i.e. it produces rejects after the AXI station, but in some applications it is directly used for process control where the data from the AXI are fed to the process and can control other variables. An often cited example is the control of the thickness of cheese slices after an AXI determined the distribution and position of 'holes' inside the cheese block. (to ensure consistent total package weight).\nRecently, automated methods have been developed for X-ray inspection of food passing by on a conveyor belt.\nUse of AXI in electronics manufacturing.\nThe increasing usage of ICs (integrated circuits) with packages such as BGAs (ball grid array) where the connections are underneath the chip and not visible, means that ordinary optical inspection is impossible. Because the connections are underneath the chip package there is a greater need to ensure that the manufacturing process is able to accommodate these chips correctly. Additionally the chips that use BGA packages tend to be the larger ones with many connections. Therefore, it is essential that all the connections are made correctly.\nAXI is often paired with the testing provided by boundary scan test, in-circuit test, and functional test.\nProcess.\nAs BGA connections are not visible, the only alternative is to use a low level inspection. AXI is able to find faults such as opens, shorts, insufficient solder, excessive solder, missing electrical parts, and mis-aligned components. Defects are detected and repaired within short debug time.\nThese inspection systems are more costly than ordinary optical systems, but they are able to check all the connections, even those underneaths the chip package.\nTo achieve highest throughput, AXI machines use single 2D X-ray images where possible to make a decision. However, as the density of components on both sides of the PCB increases, it is harder to achieve a clear 2D image that is not obscured by other components. Techniques such as Tomosynthesis are often used to filter out background components by first creating a 3D model from multiple X-ray images taken from different angles.\nRelated technologies.\nThe following are related technologies and are also used in electronic production to test for the correct operation of electronics printed circuit boards.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "13419758", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=13419758", "title": "Ethylene vinyl alcohol", "text": "Ethylene vinyl alcohol (EVOH) is a formal copolymer of ethylene and vinyl alcohol. Because the latter monomer mainly exists as its tautomer acetaldehyde, the copolymer is prepared by polymerization of ethylene and vinyl acetate to give the ethylene vinyl acetate (EVA) copolymer followed by hydrolysis. EVOH copolymer is defined by the mole % ethylene content: lower ethylene content grades have higher barrier properties; higher ethylene content grades have lower temperatures for extrusion.\nThe plastic resin is commonly used as an oxygen barrier in food packaging. It is better than other plastics at keeping air out and flavors in, is highly transparent, weather resistant, oil and solvent resistant, flexible, moldable, recyclable, and printable. Its drawback is that it is difficult to make and therefore more expensive than other food packaging. Instead of making an entire package out of EVOH, manufacturers keep costs down by coextruding or laminating it as a thin layer between cardboard, foil, or other plastics.\nIt is also used as a hydrocarbon barrier in plastic fuel tanks and pipes.\nIndustrial production.\nBecause of the high capital cost to build an EVOH plant, and the complexity of making a food grade product, only a few companies produce EVOH:\nKuraray produces EVOH resin under the name \"EVAL,\" with a 10,000 ton plant in Okayama, Japan; a 58,000 ton plant in the U.S. (near Houston, TX) under its subsidiary Kuraray America; and a 35,000 ton plant in Belgium under its subsidiary EVAL Europe.\nNippon Gohsei produces EVOH under the trade name Soarnol. It has production sites in Mizushima, Japan; La Porte, Texas in the USA; and at Salt End, Hull, England.\nChang Chun Petrochemical produces EVOH under the trade name EVASIN. It has a single site in Taipei, Taiwan.\nFood packaging.\nDue to its strong barrier against oxygen and gas, food packaging manufacturers use EVOH in their packaging structure to extend the shelf life of food products.\nMedical applications.\nEVOH is used in a liquid embolic system in interventional radiology, e.g. in Onyx. Dissolved in dimethyl sulfoxide (DMSO) and mixed with a radiopaque substance, ethylene vinyl alcohol copolymer is used to embolize blood vessels.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "39097346", "revid": "5984052", "url": "https://en.wikipedia.org/wiki?curid=39097346", "title": "E&F Miler Industries", "text": "E&F Miler Industries (formerly Miler Coaster, Inc. and Miler Manufacturing) is a family-owned roller coaster manufacturing firm based in Portland, Oregon, United States. The company specialises in smaller children's roller coasters; however, it has manufactured some larger family roller coasters in the past.\nHistory.\nIn the late 1940s Carl Miler founded Miler Manufacturing. The company built a variety steel roller coasters aimed at children and families such as Wild Mouse roller coasters. Miler Manufacturing roller coasters were popular in the 1950s. Production of new roller coasters by Miler Manufacturing stopped in the mid 1970s.\nCarl Miler's son, Fred Miler, reopened Miler Manufacturing in 1989. The company changed its name to Miler Coaster, Inc. in 1992 when its first new roller coaster was built. The company's name was later changed to E&F Miler Industries. As of 2013, Fred Miler operates the company with his son, Eric Miler.\nList of roller coasters.\nAs of 2019, E&F Miler Industries have manufactured a total of 58 roller coasters which have operated at 89 different locations. Under the Miler Manufacturing name they have manufactured a total of 30 roller coasters which have operated at 38 different locations. Aside from installing new roller coasters, E&F Miler Industries has performed work on restoring some of Miler Manufacturing's original rides. The majority of the company's contracts come from the International Association of Amusement Parks and Attractions' (IAAPA) annual trade show.", "Engineering,_Manufacturing": 0.9986382723, "qwen": "Yes"}
{"id": "39124732", "revid": "9676078", "url": "https://en.wikipedia.org/wiki?curid=39124732", "title": "Design for lean manufacturing", "text": "Design for lean manufacturing is a process for applying lean concepts to the design phase of a system, such as a complex product or process. The term describes methods of design in lean manufacturing companies as part of the study of Japanese industry by the Massachusetts Institute of Technology. At the time of the study, the Japanese automakers were outperforming the American counterparts in speed, resources used in design, and design quality. Conventional mass-production design focuses primarily on product functions and manufacturing costs; however, design for lean manufacturing systematically widens the design equation to include all factors that will determine a product's success across its entire value stream and life-cycle. One goal is to reduce waste and maximize value, and other goals include improving the quality of the design and the reducing the time to achieve the final solution. The method has been used in architecture, healthcare, product development, processes design, information technology systems, and even to create lean business models. It relies on the definition and optimization of values coupled with the prevention of wastes before they enter the system. Design for lean manufacturing is system design.\nHistory.\nNot to be confused with \"Lean Design\" (copyrighted and patented by Munro & Associates, of Michigan), design for lean manufacturing builds on the set of principles that emerged from design for the customer value and design for manufacturability. Since some lean tools are used in the practice of design for lean manufacturing, it borrows the first word in its name from lean manufacturing as exemplified by the Toyota Production System. Design for lean manufacturing was first coined by Womack, Jones, and Roos after studying the differences between conventional development at American automotive companies and lean methods at Japanese automobile producers. While lean manufacturing focuses on optimization of the production stream and removal of wastes (commonly referred to as muda, mura, and muri) once the value stream has been created, Lean Design ® (Munro & Associates) concerns itself with methods and techniques to create a lean solution from the start, resulting in more value and fewer wastes across the value stream. Lean design ® seeks to optimize the development process through rapid learning cycles to build and test multiple concepts early. Managing the knowledge value stream, systematic problem solving with analysis of the trade-offs between various design options, and solutions generated from ideas filtered by systematic innovation methods are viewed as methods within the lean design process.\nDesign for lean manufacturing overview.\nDesign for lean manufacturing is based on the premise that product and process design is an ongoing activity and not a one-time activity; therefore design for lean manufacturing should be viewed as a long-term strategy for an organization. Design for lean manufacturing must be sustainable and holistic unlike other lean manufacturing or Six Sigma approaches that either tackle only a part of the problem or tackle the problem for a short period of time. Design for lean manufacturing also relates to system thinking as it considers all aspects (or the full circle) and takes the system conditions into consideration when designing products and services, delivering them according to customer needs. ® (Munro & Associates) drives prevention of waste by adopting a systematic process to improve the design phase during development. An organizational focus is required for the implementation of Lean Design ® principles, which includes efficient and sustainable design team. Initial studies of the Japanese approach to design for lean manufacturing noted four principles; leadership of projects by a (or project boss), tightly knit teams, communication on all of the difficult design trade-offs, and simultaneous development between engineering and manufacturing. Further study showed additional depth to the principles, citing 13 principles specific to the Toyota design for lean manufacturing methods in product and process development in the areas of process, skilled people, and tools and technology. As the practice of design for lean manufacturing has expanded in its depth and breadth of application, additional principles have been integrated into the method.\nThe dimensions of lean in design and development.\nTo be successful, a corporate wide design for lean manufacturing implementation typically includes the following dimensions:\nWhen the dimensions are fully deployed in an organization, design for lean manufacturing enhances the performance levels with respect to design and innovation. Shingo assessments measure lean implementations in all parts of the organization, including the design methodology. The Shingo Prize for Excellence in Manufacturing is given annually for operational excellence in North America. Using design for lean manufacturing practices helps organizations move toward Shingo excellence.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "32424204", "revid": "45021877", "url": "https://en.wikipedia.org/wiki?curid=32424204", "title": "Hudson-Sharp Machine Company", "text": "Hudson-Sharp Machine Company is active in the design and manufacture of plastic bag making machinery, pouch making equipment, and reclosable packaging solutions.\nCompany profile.\nThe Hudson-Sharp Machine Company is involved in the design and manufacture of plastic bag making machinery, pouch making equipment, and reclosable packaging solutions. With manufacturing and sales throughout the world, Hudson-Sharp has been in business for over 100 years. A partial list of product categories include:\nHistory.\n1870\nA small machine shop began operation along the East River in what is now the city of Green Bay, WI, United States. The company repaired steamboats and manufactured parts for sawmill machinery.\n1910\nDavid Hudson & Alexander Sharp took over the small shop and expanded the company into developing equipment for paper mills, winders for toilet tissue, and produced high-speed folders for tissue and napkins.\n1925\nHudson-Sharp began manufacturing printing presses and manufactured the first central impression aniline press built in the United States.\n1947\nS.J. Campbell purchased the Hudson-Sharp Machine Company and conceived, designed, and patented the Campbell Wrapper, the world's first horizontal form, fill, and seal machine. Variations of the Campbell Wrapper are still used today throughout the world in wrapping candy, cheese, bakery products, and other various items.\n1956\nFMC Corporation acquired Hudson-Sharp as a part of the Packaging Machinery Division with divisional headquarters in Horsham, PA. Over the next decade, the company continued to grow by introducing several innovative packaging machinery lines. The first side-weld bag machine produced was nicknamed the \"Flyswatter\". Also, the first wicket stacker machine was developed.\nBesides innovations, Hudson-Sharp introduced their products into new regions around the globe, specifically the Australia/Asia region. Those regions are still supported to this day.\n1967\nSupport began in European markets as operations began in Aalst, Belgium. The Aalst facility was responsible for the sales and service of plastic bag converting equipment, the manufacture of machinery for cardboard and plastic set-up boxes, horizontal packaging machinery, and paper tissue machines.\n1970\nWicketer development continues and Servo technology was introduced.\n1978\nHigh-speed rotary side-weld machines for the production of large trash bags were introduced.\n1986\nPlastic grocery bag line introduced.\n1989\nThe first commercially-produced, servo-driven wicketer was introduced.\n1997\nHudson-Sharp introduces INNO-LOK pre-zippered film reclosable packaging.\n1998\nDivestiture from FMC becomes The Hudson-Sharp Machine Company once again.\n2000\nHot melt glue patch handle line introduced.\n2004\nHudson-Sharp acquires Amplas and expands the product offering of bottom-seal technology.\n2006\nSide Gusset Bottom Seal Pouch Machine with patented Inno-Lok transverse direction zipper applicator introduced.\n2007\nNTR800 Roll to Roll Machine introduced.\n2008\nHudson-Sharp introduces new generation servo pouch machinery.\nA new packaging design was introduced called, Pour & Lok. It is a side gusseted, pour spout packaging application for pre-zippered roll stock.\n2009\nHudson-Sharp is acquired by Thiele Technologies, part of the family of Barry-Wehmiller Companies. Thiele Technologies acquires certain assets of RO-AN through a secured third-party sales transaction.\n2010\n100-year anniversary of the Hudson-Sharp Machine Company.\n2019\nThe Hudson-Sharp Machine Company joins the PCMC family and continues to be involved in the design and manufacture of plastic bag-making machinery, pouch-making equipment, and reclosable packaging solutions.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "18654720", "revid": "22837787", "url": "https://en.wikipedia.org/wiki?curid=18654720", "title": "Organic solderability preservative", "text": "Organic solderability preservative or OSP is a method for coating of printed circuit boards. It uses a water-based organic compound that selectively bonds to copper and protects the copper until soldering.\nThe compounds typically used are from the azole family such as benzotriazoles, imidazoles, benzimidazoles. These adsorb on copper surfaces, by forming coordination bonds with copper atoms and form thicker films\nthrough formation of copper (I) – N–heterocycle complexes. The typical film thickness used is in the tens to hundreds of nanometers.", "Engineering,_Manufacturing": 0.9973897338, "qwen": "Yes"}
{"id": "18656877", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=18656877", "title": "Bearing reducer", "text": "A Bearing reducer in engineering is a bearing that designates the full integration of high-precision reduction gear and high-precision radial-axial bearing in a compact unit. This transmission system allows the utilization of the bearing reducer in several technics, such as robotics and automation, machine tools, measuring equipment, navigation systems, the aircraft industry, the military and medicine field, the woodworking field, the printers branch, the machines for the textile industry and glass treatment, and the filling machines.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "18657445", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=18657445", "title": "Manufacturing operations management", "text": "Manufacturing operations management (MOM) is a collection of systems for managing end-to-end manufacturing processes with a view to optimizing efficiency.\nThere are many types of MOM software, including for production management, performance analysis, quality and compliance, and human machine interface (HMI). Production management software provides real-time information about jobs and orders, labor and materials, machine status, and product shipments. Performance analysis software displays metrics at the machine, line, plant and enterprise level for situational or historical analysis. Quality and compliance software is used to promote compliance with standards and specifications for operational processes and procedures. HMI software is a form of manufacturing operations management (MOM) software that enables operators to manage industrial and process control machinery using a computer-based interface.\nEmerging Software Trends\nAdvancements in technology and market demands are enabling new capabilities in MOM software platforms, gradually closing gaps in end-user needs.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "23761733", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=23761733", "title": "Hot metal gas forming", "text": "Hot metal gas forming (HMGF) is a method of die forming in which a metal tube is heated to a pliable state, near to but below its melting point, then pressurized internally by a gas in order to form the tube outward into the shape defined by an enclosing die cavity. The high temperatures allow the metal to elongate, or stretch, to much greater degrees without rupture than are possible in previously utilized cold and warm forming methods. In addition, the metal can be formed into finer details and requires less overall forming force than traditional methods.\nHistory and comparison with previous techniques.\nHMGF is an evolution in the cost effectiveness and applicability of several existing commercial processes: superplastic forming, hot blow forming, and hydroforming.\nComplex tubes can be made from multiple sheet components formed and welded together, but this adds unnecessary cost and creates quality concerns at the joints. Hydroforming uses liquid under extreme pressures to form metal tubes. It was developed for the plumbing industry and by 1990 achieved production efficiencies suited for high volume autos. Typically hydroforming is done at ambient temperatures, and limits the forming elongation of metals to 8–12% diameter increase for aluminum, and 25–40% for steel. This limits the part shape complexity that can be produced. In addition, the workcenters and tooling can be large and expensive because of the internal fluid pressures required to form ambient tubes. HMGF is able to form tubes with larger shape complexity in only one forming step and generally at a lower internal pressure than in conventional tube hydroforming.\nBlow forming started with glass long ago, and is now a widespread method for forming plastic into hollow structures. Again, the heated material properties provide for many processing advantages. Warm forming has been the subject of extensive research in the past decades. It is defined as forming above ambient but below the recrystallization temperature of an alloy, and using hydroform principles, can be done on tubes. Temperatures are typically limited due to safety concerns surrounding the heated forming fluids. At these temperatures, cycle times may still be relatively long, and elongations still do not approach that of hot forming.\nSuperplastic forming is often applied in the aerospace industry, but it requires the use of very fine grain metal alloys, deformed up to very large strain values, but at a very low strain rate. HMGF is therefore potentially faster than superplastic forming. \nAs a natural evolution, the need for HMGF created research starting in the 1990s. Fast cycle times, inexpensive tooling and machinery resulting from pressures an order of magnitude lower than hydroforming, and extreme forming ratios due to high temperature forming create a compelling business case for high volume low cost manufacturing.\nIn 1999, development of the HMGF techniques began as an Advanced Technology Program (ATP) project funded by the US National Institute of Standards and Technology (NIST). This project completed in 1993 and research showed up to 150% expansion ratios for aluminum and 50% with steel were possible, with further expansion capabilities by use of end feeding of material to minimize wall thinning. \nIn order to keep pace with the US research, a European project was funded by the Research Fund for Coal and Steel (RFCS). Starting in July 2004, with a duration of 3 years, this project further investigated the HMGF process. By 2007, the consortium of European research and commercial entities proved concepts of simpler heating and die construction, and while focusing on the more demanding steel alloys, illustrated free deformation of 140% by use of end feeding to control wall thinning and delay rupture. The method used in these experiments is patented under .\nAlso in Europe, parallel research yielded an innovative approach to the concept. By 2006, the HEATform method of hot metal gas forming showed evidence of unique metal shapes that had \"historically only been possible in the domain of glass blowing and blow molded parts\" with aluminum forming in excess of 270% expansion ratio at a production intended cycle time of 20 seconds. Citing that hardening and subsequent breakage will limit forming of the aluminum alloy below , the best flow behavior was observed at . This is significantly higher than the capabilities of warm liquid or warm gas pressure forming. The HEATform techniques of end feeding control achieved uniform wall thickness up to 300% strain values.\nWhile significant research into material compatibility and predictive analysis techniques is ongoing, hot metal gas forming has been commercialized by at least one company who is providing hot expansion coupled with material end feeding.\nApplications.\nTypical applications are in the automotive and aerospace industries where the precursor technology of hydroforming is well known. Other applications include sports equipment and furniture. The multi-material capability are used in decorative workpieces and plumbing fixtures.\nMaterials.\nThe HMGF process is compatible with almost any metal. The most significant benefit of HMGF is that cold form resistant materials become viable for complex forming. Often, alloys are enhanced with expensive materials to enable cold forming and increase machinability, however with HMFG a less expensive alloy can be used, which reduces piece prices. One example is the use of ferritic stainless steels, like the 1.4512 alloy for exhaust components. Typically, the more expensive austenitic stainless is chosen, like the 1.4301 alloy, for parts requiring complex forming due to its 40% advantage in ambient formability (38.5% vs. 27.4% typical A%).\nHardenable metal alloys (e.g. boron steels) can be used in HMGF. In this case the die can be used not only as a shaping tool, but also as a tempering tool, so that the final hardness of the formed tube after forming and cooling is increased. The process is often called \"press hardening\" in this case.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "60844791", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=60844791", "title": "Austempered Ductile Iron", "text": "Austempered Ductile Iron (ADI) is a form of ductile iron that enjoys high strength and ductility as a result of its microstructure controlled through heat treatment. While conventional ductile iron was discovered in 1943 and the austempering process had been around since the 1930s, the combination of the two technologies was not commercialized until the 1970s.\nMicrostructure.\nLike all ductile iron, ADI is characterized by its spheroidal graphite nodules spaced within the matrix. These nodules reduce microsegregation of solutes within the material. For ADI, the material has been austempered such that the matrix is transformed into ausferrite, or a mixture of acicular ferrite and austenite. The microstructure is used to classify ADI into grades, which depend on the heat treatment process and not the composition of the material.\nMechanical properties.\nThe high strength and ductility of ADI are a direct result of its microstructure. Specifically, the ductility of ductile irons is a result of the lack of bainite in the matrix. Rather, the austempering process forms acicular ferrite and austenite. The latter of these has a face-centered cubic (FCC) structure. The FCC has 12 slip systems that allow for dislocations motion, resulting in high ductility in the austenitic phase of ADI. This ductility also translates to relatively high toughness in ADI. \nThe increase in ductility that ADI exhibits over other form of cast iron also comes as a result of the spheroidal graphite. As compared to the flake-like graphite present in gray iron, for example, the spheroidal graphite nodes are relatively easy for dislocations to bypass, increasing the ductility of the material. These nodules also decrease the stress concentration compared to flakes, as stress at the tip of an inclusion is proportional to the radius of curvature. The large radius prevents the propagation of cracks in the material, further resulting in high ductility and good fatigue properties in the material. \nSome of the austenite phase mentioned above is mechanically metastable and will form martensite when subjected to high stress. The combination of hard, wear-resistant martensite with ausferrite results in good wear properties, as the regions near a crack tip strengthen and prevent further propagation. This is not an example of work hardening, which multiplies dislocations that inhibit each other's growth and result in higher strength. Rather, a phase transformation is taking place as a result of applied stress.\nThe mechanical properties of ADI are extremely dependent on processing. Wide ranges in strength and ductility are possible. High temperature heat treatment (>400C) results in high ductility, good impact toughness, with a yield strength around 500 MPa. Lower temperatures (~260C) results in a higher yield strength of 1400 MPa and high hardness but much lower ductility.", "Engineering,_Manufacturing": 1.0000058413, "qwen": "Yes"}
{"id": "60852572", "revid": "199747", "url": "https://en.wikipedia.org/wiki?curid=60852572", "title": "Design culture", "text": "Design culture is an organizational culture focused on approaches that improve customer experiences through design. In every firm, the design is significant since it allows the company to understand users and their needs. Integration of design culture in any organisation aims at creating experiences that add value to their respective users. In general, design culture entails undertaking design as the forefront of every operation in the organisation, from strategy formulation to execution. Every organisation is responsible for ensuring a healthy design culture through the application of numerous strategies. For instance, an organisation should provide a platform that allows every stakeholder to engage in design recesses. Consequently, everyone needs to incorporate design thinking, which is associated with innovation and critical thinking.\nMoreover, design culture has many characteristics that create a conducive integration within that work environment. It offers freedom to fail that presents an opportunity for design experimentation. Design process entails taking risks that are mistake bounded. Therefore, individuals involving in design processes learn from their mistakes and become more innovative. Hence design culture encourages risk taking in design processes that facilitate innovation and creativity in an organisation. Proactivity in design culture has an impact on the organisation, specifically on decision making and problem-solving. Design culture allows designers to engage in constructive tasks. In the process, designers can solve problems in an organisation and make crucial decisions towards innovations of the organisation. Design culture is concerned with the human side of the respective organisation. In the recent past, organisations have been running based on data-driven mentality with the success of the organisation measured through the level of efficiency in the operations. In contrast, design culture is interested in the participation of human in determining the success of the organisation through the level of innovation facilitated by their involvement. In return, design culture concerned with improving an organisation's culture into a pleasant and change have driven culture.\nDeveloping a design culture.\nCreation of a design culture for an organisation leads to a better transformation of the organisation. According to a study conducted by Forrester Research Consulting in the year 2016, to investigate whether the design-led cultures gave companies a significant advantage in the business or not, it was evident that most of the enterprises that analysed during the research had digital experiences that outpaced competition. The study proved that focusing on design strengthens an organisation from the inside as well as from the outside.\nIn a design-led enterprise, the design permeates the organisation beyond the product teams that embedded in the culture and such organisations; there is always an ambition to do better.\nThese companies typically support a variety of skills from the more oriented designers to the junior designers or the more tactical designers. The teams use collaborative processes and tools in unifying the working groups of the organisation. An organisation driven by design is more proactive rather than reactive, and they tend to confirm the next challenge rather than waiting until the challenge presents itself. This is made possible by the values that built based on, which is done through collaboration, experimentation, empathy as well as user researches.\nFurthermore, developing design culture requires a definition of the design and the necessary resources that will facilitate its integration into the organisation. This follows an evaluation of the organisation's stakeholders who will be involved in the design process. The evaluation depends on the organisation's culture, which is the defining aspect of an organisation's life. Consequently, identifying the designers to be involved in the designing process requires an in-depth understanding of the purpose of the design towards the organisation's culture and innovation as well.\nAdditionally, building a design culture entails creating an environment that presents a platform that ensures that every individual obtains solutions to some problems present in the organisation. There exist several factors necessary for developing a design culture in any organisation. Cultivating culture is the first approach towards developing design culture. This step entails identifying individuals, their characters, and including them into the design process. The management involved in the design process needs to set the tone for the organisation's culture. Besides, design culture needs to develop an organisation's value in line with the design and ensure that every member of the design team incorporates them in the field of interest.\nDeveloping design culture require incorporation of skilled personnel, innovative and creative individuals as well. However, identifying such individuals, it takes a process that will present an effective design process. Therefore, the management needs to integrate an effective interview process that will help in the selection of the best skills. Also, it will require motivation for the personnel involved and be in line with the organisation's values. The design culture needs to foster social capital that is responsible for higher information flow, effective collaboration and collective action of the team. Therefore, building a design culture should facilitate the creation of employees values, recognition of their achievements, enhance communication in the organisation and establish a firm organisation.\nAddressing markets and society.\nDesign culture plays a significant role in marketing systems and the surrounding society. It addresses market externalities and internalises associated with the overall performance of the organisations. In addition, design culture allows an organisation to understand users in the society and their needs hence playing a significant role in the business. Through design culture, the organisation supports more strategically oriented designers from the society that ensure effective operation in the business. A design-driven organisation tends to be more proactive in the market by defining challenges and strategically working to improve its overall performance. Design culture facilitates the growth of a firm from tiny startups to legacy enterprises. Therefore, in markets and societies, design culture aims at improving an organisation's output to the excellent quality of products, services and the overall societal relationships.\nAdditionally, design culture needs to consider the aspects of the surrounding society and ensure that the design process is incorporative of the values and culture that is in line with the societal culture defining the surrounding community. The society plays a significant role in the design culture by presenting skilled personnel who can be recruited into the design process. In relation to society, design culture aims at designing a brand for everyone. I. Moreover, the community presents a ready market for the brands designed by the organisation. Consequently, the branding process should consider all the necessary qualities that will maintain the brand in the market. This enhanced through consideration of the values defining the surrounding society. Moreover, the organisation's culture should be at per with the societal culture in order to promote collaboration.\nDesign culture aims at enhancing collaboration in the market with the respective stakeholders. Therefore, introducing design into the market requires intense research and planning that will facilitate the production of a brand that fits the requirements for all. The design process needs to be aware of the market trends and branded products with the aim of solving an existing problem in the market. In addition, the design process should involve designing a brand that provides a solution to various situations in the society. Addressing the market, design culture is concerned about developing a brand that meets the best competitive qualities. Through innovation, the organisation involved in the design process conducts research on different market trends and comes up with refined approaches to be integrated into the design process. Moreover, the organisation needs to maintain its culture that uniquely defines its operations and products in the market. Concerned about the future trend of the design, the management responsible for the design process need to ensure that necessary qualities are met in the design process \nPositioning design professions.\nAs a guiding truth towards the successful firm organisation, design culture takes a psychological approach to different operations of the business. Positioning design professions entails defining numerous approaches necessary for building a healthy design culture. In addition, it focuses on professional strategies that get prospects and customers preferences that enable a business to stand firm in a competitive market. A design-centric organisation is usually biased against leaving anything to chance. A healthy design culture applies professional not only to the product but also to the organisation itself.  Products usually reflect the structure as well as the character of the organisation that is responsible for their production. A well-designed enterprise is capable of producing well-designed products and services. In a healthy design culture, everyone has a feeling of empowerment towards participation in the design process. Employees are usually encouraged to carry out experimentations with the understanding that they will often lead to mistakes, and this should not be a hindrance.\nDesign culture has innovation as one of the cultural traits. Therefore, the design profession is crucial in the design process as it incorporates necessary branding skills, design skills and knowledge of the design process. The process of cultivating culture requires skills necessary for analysing the surrounding society and determining the required skills for the design process. Setting the tone for an organisation is a professional approach that requires the development of an organisation's values. The design management needs to demonstrate knowledge and an understanding of the conduct of the design team and the level of innovation necessary for the design process.\nFurthermore, positioning the design profession requires increased diversity that facilitates innovation. Gender diversity should be maintained in determining the team that will be involved in the design process. In addition, diversity brings individuals together who have varying skills, creativity and knowledge that help in branding different products. Branding a product for everyone in society requires extensive research. As a result, the research requires a professional approach that will help in identifying the cultural aspects defining the society. Moreover, identification of the market trends requires in-depth analysis approaches that are in line with design professions. Therefore, the design management team need to ensure an effective and strong position in the design culture that enhances innovation in the design process \nLocating Design culture.\nEffective design culture has to be made with intention and put into practice consistently. This requires the definition of approaches necessary for locating design culture. Discovering design culture is facilitated by the need to obtain a solution to a given challenge or the need to major on problem-solving approaches. Locating design culture is done through experimentation, collaboration, user research and empathy. It is a common characteristic for many companies to build a third design culture through trial and error. For example, a company such as Apple has been fine-tuning its design culture for about three decades, a corny though a relevant adage. Locating design culture require an effective definition of the characteristics of a robust design culture. It requires frequent experimentation that allow individuals to explore numerous solutions as possible that result in successful launches. In addition, locating design culture entails implementation of a system that provides answers for questions raised concerning the design culture. Moreover, it involves locating different tools that encourage collaboration allowing a given team to formulate plans, design presentations and work together for successful design culture. Concerning idea generation, it is a norm for every organisation to keep coming up with new ideas now and then, and this allows the organisation to iterate and even receive feedback more efficiently and in a short time ", "Engineering,_Manufacturing": 0.9849594831, "qwen": "Yes"}
{"id": "28087852", "revid": "5984052", "url": "https://en.wikipedia.org/wiki?curid=28087852", "title": "Raise the Roof (producer)", "text": "Raise the Roof is a Broadway producing entity. It is composed of the producers Harriet Leve, Jennifer Isaacson, and the members of WalkRunFly Productions: Brandon Victor Dixon and Warren Adams.\nThe group was founded by Jean Doumanian, Elaine Krauss, Harriet Leve, and Jennifer Isaacson. Their first venture together was \"Burn the Floor\" as Raise the Roof 1. Next, Krauss, Leve, and Manocherian came together as Raise the Roof 2 to produce the recent Broadway production of \"Superior Donuts\" by Tracy Letts, the Pulitzer Prize winning playwright of \"\". Doumanian was a lead producer on that production. In 2010, the group, as Raise the Roof 3, produced the Tony nominee for Best Revival, \"A Little Night Music\", starring Catherine Zeta Jones (who won a Tony for this performance) and Angela Lansbury (who was nominated for a Tony for this performance). On July 13, 2010, Broadway legends Bernadette Peters and Elaine Stritch joined the cast and assumed those roles. They were also represented, as Raise the Roof 4, by the Tony Award winning Best Revival of \"La Cage Aux Folles\", starring Kelsey Grammer (who was nominated for a Tony for this performance) and Douglas Hodge (who won a Tony for this performance).\nProductions.\nLa Cage Aux Folles [Revival, Musical] \nA Little Night Music [Revival, Musical] \nSuperior Donuts [Original, Play] \nBurn the Floor [Dance] \nAwards and nominations.\nLa Cage Aux Folles.\nTONY AWARDS\n2010 Tony Award Best Revival of a Musical [WINNER]\n2010 Tony Award Best Leading Actor in a Musical\n2010 Tony Award Best Featured Actor in a Musical\n2010 Tony Award Best Direction of a Musical\n2010 Tony Award Best Choreography\n2010 Tony Award Best Orchestrations\n2010 Tony Award Best Scenic Design of a Musical\n2010 Tony Award Best Costume Design of a Musical\n2010 Tony Award Best Lighting Design of a Musical\n2010 Tony Award Best Sound Design of a Musical\nDRAMA DESK AWARDS\n2010 Drama Desk Award Outstanding Revival of a Musical [WINNER]\n2010 Drama Desk Award Outstanding Actor in a Musical\n2010 Drama Desk Award Outstanding Featured Actor in a Musical\n2010 Drama Desk Award Outstanding Director of a Musical\n2010 Drama Desk Award Outstanding Choreography in a Musical\n2010 Drama Desk Award Outstanding Costume Design\n2010 Drama Desk Award Outstanding Sound Design in a Musical\nA Little Night Music.\nTONY AWARDS\n2010 Tony Award Best Revival of a Musical [nominee]\n2010 Tony Award Best Leading Actress in a Musical\n2010 Tony Award Best Featured Actress in a Musical\n2010 Tony Award Best Sound Design of a Musical\nDRAMA DESK AWARDS\n2010 Drama Desk Award Outstanding Revival of a Musical [nominee]\n2010 Drama Desk Award Outstanding Actress in a Musical\n2010 Drama Desk Award Outstanding Featured Actress in a Musical\nSuperior Donuts.\nTONY AWARDS\n2010 Tony Award Best Featured Actor in a Play", "Engineering,_Manufacturing": 0.9995777011, "qwen": "Yes"}
{"id": "28094935", "revid": "21857263", "url": "https://en.wikipedia.org/wiki?curid=28094935", "title": "First-pass yield", "text": "First-pass yield (FPY), also known as throughput yield (TPY), is defined as the number of units coming out of a process divided by the number of units going into that process over a specified period of time.\nExample.\nConsider the following:\nYou have a process that is divided into four sub-processes: A, B, C and D. Assume that you have 100 units entering process A. To calculate first time yield (FTY) you would:\nFor example:\n(# units leaving the process as good parts) / (# units put into the process) = FTY\nThe total first time yield is equal to FTYofA * FTYofB * FTYofC * FTYofD or 0.9000 * 0.8889 * 0.9375 * 0.9333 = 0.7000.\nYou can also get the total process yield for the entire process by simply dividing the number of good units produced by the number going into the start of the process. In this case, 70/100 = 0.70 or 70% yield.\nThe same example using first pass yield (FPY) would take into account rework:\nFirst pass yield is only used for an individual sub-process. Multiplying the set of processes would give you Rolling throughput yield (RTY). RTY is equal to FPYofA * FPYofB * FPYofC * FPYofD = 0.8500 * 0.8889 * 0.8125 * 0.8267 = 0.5075\nNotice that the number of units going into each next process does not change from the original example, as that number of good units did, indeed, enter the next process. Yet the number of FPY units of each process counts only those that made it through the process as good parts that needed no rework to be good parts. The calculation of RTY, rolling throughput yield, shows how good the overall set of processes is at producing good overall output without having to rework units.", "Engineering,_Manufacturing": 0.9999905825, "qwen": "Yes"}
{"id": "1722960", "revid": "11555324", "url": "https://en.wikipedia.org/wiki?curid=1722960", "title": "Hydroforming", "text": "Hydroforming is a cost-effective way of shaping ductile metals such as aluminium, brass, low alloy steel, and stainless steel into lightweight, structurally stiff and strong pieces. One of the largest applications of hydroforming is the automotive industry, which makes use of the complex shapes made possible by hydroforming to produce stronger, lighter, and more rigid unibody structures for vehicles. This technique is particularly popular with the high-end sports car industry and is also frequently employed in the shaping of aluminium tubes for bicycle frames.\nHydroforming is a specialized type of die forming that uses a high pressure hydraulic fluid to press room temperature working material into a die. To hydroform aluminium into a vehicle's frame rail, a hollow tube of aluminium is placed inside a negative mold that has the shape of the desired result. High pressure hydraulic pumps then inject fluid at very high pressure inside the aluminium tube which causes it to expand until it matches the mold. The hydroformed aluminium is then removed from the mold.\nHydroforming allows complex shapes with concavities to be formed, which would be difficult or impossible with standard solid die stamping. Hydroformed parts can often be made with a higher stiffness-to-weight ratio and at a lower per unit cost than traditional stamped or stamped and welded parts. Virtually all metals capable of cold forming can be hydroformed, including aluminium, brass, carbon and stainless steel, copper, and high strength alloys.\nIf electrodes are used to vaporize the fluid explosively in an arc this would describe a similar process known as electrohydraulic forming.\nMain process variants.\nSheet hydroforming.\nThis process is based on the 1950s patent for hydramolding by Fred Leuthesser, Jr. and John Fox of the Schaible Company of Cincinnati, Ohio in the United States. It was originally used in producing kitchen spouts. This was done because in addition to the strengthening of the metal, hydromolding also produced less \"grainy\" parts, allowing for easier metal finishing.\nIn sheet hydroforming there are bladder forming (where there is a bladder that contains the liquid; no liquid contacts the sheet) and hydroforming where the fluid contacts the sheet (no bladder). Bladder forming is sometimes called flexforming. Flexforming is mostly used for low volume productions, as in the aerospace field.\nForming with the fluid in direct contact with the part can be done either with a male solid punch (this version is sometimes called hydro-mechanical deep drawing) or with a female solid die.\nIn hydro-mechanical deep drawing, a work piece is placed on a draw ring (blank holder) over a male punch then a hydraulic chamber surrounds the work piece and a relatively low initial pressure seats the work piece against the punch. The punch then is raised into the hydraulic chamber and pressure is increased to as high as 100 MPa (15000 psi) which forms the part around the punch. Then the pressure is released and punch retracted, hydraulic chamber lifted, and the process is complete.\nAmong these techniques hydraulic bulge testing allows for an increased work hardening of sheet material by distinctive stretching operations and provides better shape accuracy for complex parts. Hence, by selecting proper material and the forming parameters for hydraulic sheet bulging study one can determine Forming Limit Curves (FLCs). \nSignificance\nTube hydroforming.\nIn tube hydroforming there are two major practices: high pressure and low pressure.\nWith the high pressure process the tube is fully enclosed in a die prior to pressurization of the tube. In low pressure the tube is slightly pressurized to a fixed volume during the closing of the die (this used to be called the Variform process). Historically, the process was patented in the '50s, but it was industrially spread in the 1970s for the production of large T-shaped joints for the oil and gas industry. Today it is mostly used in the automotive sector, where many industrial applications can be found. With the rise of the electric bicycle it is now a method of choice for e-bicycle manufacturers. Especially down tubes and top tubes are favorably made with hydroforming in order to fit the battery for the electric bicycle. Newest applications in the bicycle industry are now hydroformed handlebars to improve aero dynamics and ergonomics.\nIn tube hydroforming pressure is applied to the inside of a tube that is held by dies with the desired cross sections and forms. When the dies are closed, the tube ends are sealed by axial punches and the tube is filled with hydraulic fluid. The internal pressure can go up to a few thousand bars and it causes the tube to calibrate against the dies. The fluid is injected into the tube through one of the two axial punches. Axial punches are movable and their action is required to provide axial compression and to feed material towards the center of the bulging tube. Transverse counterpunches may also be incorporated in the forming die in order to form protrusions with small diameter/length ratio. Transverse counter punches may also be used to punch holes in the work piece at the end of the forming process. \nDesigning the process has in the past been a challenging task, since initial analytical modeling is possible only for limited cases. Advances in FEA and FEM in recent years has enabled hydroform processes to be more widely engineered for varieties of parts and materials. Often FEM simulations must be performed in order to find a feasible process solution and to define the correct loading curves: pressure vs. time and axial feed vs. time. In the case of more complex tube hydroformed parts the tube must be pre-bent prior to loading into the hydroforming die. Bending is done sequentially along the length of the tube, with the tube being bent around bending discs (or dies) as the tube length is fed in. Bending can be done with or without mandrels. This additional complexity of process further increases the reliance on FEM for designing and evaluating manufacturing processes. The feasibility of a hydroforming process must take into consideration the initial tube material properties and its potential for variation, along with the bending process, hydraulic pressure throughout the forming process, in inclusion of axial feed or not, in order to predict metal formability. \nTypical tools.\nTools and punches can be interchanged for different part requirements.\nOne advantage of hydroforming is the savings on tools. For sheet metal only a draw ring and punch (metalworking) or male die is required. Depending on the part being formed, the punch can be made from epoxy, rather than metal. The bladder of the hydroform itself acts as the female die eliminating the need to fabricate it. This allows for changes in material thickness to be made with usually no necessary changes to the tool. However, dies must be highly polished and in tube hydroforming a two-piece die is required to allow opening and closing.\nGeometry produced.\nAnother advantage of hydroforming is that complex shapes can be made in one step. In sheet hydroforming with the bladder acting as the male die almost limitless geometries can be produced. However, the process is limited by the very high closing force required in order to seal the dies, especially for large panels and thick hard materials. Small concave corner radii are difficult to be completely calibrated, i.e. filled, because too large a pressure would be required. in fact, the die closing force can be very high, both in tube and sheet hydroforming and may easily overcome the maximum tonnage of the forming press. In order to keep the die closing force under prescribed limits, the maximum internal fluid pressure must be limited. This reduces the calibration abilities of the process, i.e. it reduces the possibility of forming parts with small concave radii.\nLimits of the sheet hydroforming process are due to risks of excessive thinning, fracture, wrinkling and are strictly related to the material formability and to a proper selection of process parameters (e.g. hydraulic pressure vs. time curve). Tube hydroforming can produce many geometric options as well, reducing the need for tube welding operations. Similar limitations and risks can be listed as in sheet hydroforming; however, the maximum closing force is seldom a limiting factor in tube hydroforming.\nTolerances and surface finish.\nHydroforming is capable of producing parts within tight tolerances including aircraft tolerances where a common tolerance for sheet metal parts is within 0.76 mm (1/30th of an inch). Metal hydroforming also allows for a smoother finish as draw marks produced by the traditional method of pressing a male and female die together are eliminated. \nWhile springback has long been a topic of discussion for sheet metal forming operations it has been far less of a topic of research for tube hydroforming. This may in part be a result of the relatively low levels of springback naturally occurring when deforming the tubes into their closed section geometries. Tube Hydroformed sections by the nature of their closed sections are very rigid and do not display high degrees of elastic deformation under load. For this reason it is likely that negative residual stress induced during tube hydroforming might be insufficient to deform the part elastically after the completion of forming. However, as more and more tubular parts are being manufactured using high strength steel and advanced high strength steel parts, springback must be accounted for in the design and manufacture of closed section tube hydroformed parts.\nExamples.\nNotable examples include:\nReferences.\n", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1724001", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=1724001", "title": "Job shop", "text": "Job shops are typically small manufacturing systems that handle job production, that is, custom/bespoke or semi-custom/bespoke manufacturing processes such as small to medium-size customer orders or batch jobs. Job shops typically move on to different jobs (possibly with different customers) when each job is completed. Job shops machines are aggregated in shops by the nature of skills and technological processes involved, each shop therefore may contain different machines, which gives this production system processing flexibility, since jobs are not necessarily constrained to a single machine. In computer science the problem of job shop scheduling is considered strongly NP-hard.\nA typical example would be a machine shop, which may make parts for local industrial machinery, farm machinery and implements, boats and ships, or even batches of specialized components for the aircraft industry. Other types of common job shops are grinding, honing, jig-boring, gear manufacturing, and fabrication shops.\nThe opposite would be continuous continuous-flow manufacturing, such as textile, steel, food manufacturing and manual labor.\nAdvantages.\nCompare to transfer line.\nDisadvantages.\nCompare to transfer line.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1724021", "revid": "4796325", "url": "https://en.wikipedia.org/wiki?curid=1724021", "title": "Project manufacturing", "text": "Project manufacturing is an operation designed to produce large, expensive, specialized products such as custom homes, defense weapons such as aircraft carriers and submarines, and aerospace products such as passenger planes, and the Space Shuttle. \nProject manufacturing is highly flexible, because each project is usually significantly different from the one before it, even if the project’s size and expense and high degree of customization, project manufacturing can take an extremely long time to complete.\nProject Manufacturing is an operation designed to produce unique but similar products. It takes advantage of common manufacturing requirements (and therefore efficiencies), while allowing for customization into “unique” combinations. Unique orders may be managed like a project. The more components of that order that are common to other unique orders the more they may be manufactured – taking advantage of manufacturing methodology. Project Manufacturing then is the melding of Manufacturing and Project Management at a level where the most advantage may be gleaned from each to the financial advantage of the company.", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "19320164", "revid": "38656112", "url": "https://en.wikipedia.org/wiki?curid=19320164", "title": "Microflex Inc.", "text": "Microflex Inc. is an international corporation manufacturing flexible metal products based in Ormond Beach, Florida and supplying a wide range of industries, with customers including NASA. It was founded in 1975 by Josif and Gjorgjija 'George' Atanasoski. It was originally located in New Haven, Connecticut, however it was relocated to Ormond Beach, Florida in 1980.\nMicroflex Inc. manufacture metal hose and braid, metallic expansion joints, bellows, and automotive products.\nMicroflex Inc. hold the following certificates: ASME Certification, ISO Certification, and PED Certification.", "Engineering,_Manufacturing": 0.9998158813, "qwen": "Yes"}
{"id": "19327123", "revid": "36942950", "url": "https://en.wikipedia.org/wiki?curid=19327123", "title": "Vision-guided robot systems", "text": "A vision-guided robot (VGR) system is basically a robot fitted with one or more cameras used as sensors to provide a secondary feedback signal to the robot controller to more accurately move to a variable target position. VGR is rapidly transforming production processes by enabling robots to be highly adaptable and more easily implemented, while dramatically reducing the cost and complexity of fixed tooling previously associated with the design and set up of robotic cells, whether for material handling, automated assembly, agricultural applications, life sciences, and more.\nIn one classic though dated example of VGR used for industrial manufacturing, the vision system (camera and software) determines the position of randomly fed products onto a recycling conveyor. The vision system provides the exact location coordinates of the components to the robot, which are spread out randomly beneath the camera's field of view, enabling the robot arm(s) to position the attached end effector (gripper) to the selected component to pick from the conveyor belt. The conveyor may stop under the camera to allow the position of the part to be determined, or if the cycle time is sufficient, it is possible to pick a component without stopping the conveyor using a control scheme that tracks the moving component through the vision software, typically by fitting an encoder to the conveyor, and using this feedback signal to update and synchronize the vision and motion control loops.\nSuch functionality is now common in the field of vision-guided robotics (VGR). It is a fast-growing rapidly evolving technology proving to be economically advantageous in countries with high manufacturing overheads and skilled labor costs by reducing manual intervention, improving safety, increasing quality, and raising productivity rates, among other benefits.\nVision systems for robot guidance.\nA vision system comprises a camera and microprocessor or computer, with associated software. This is a very wide definition that can be used to cover many different types of systems which aim to solve a large variety of different tasks. Vision systems can be implemented in virtually any industry for any purpose. It can be used for quality control to check dimensions, angles, colour or surface structure-or for the recognition of an object as used in VGR systems.\nA camera can be anything from a standard compact camera system with integrated vision processor to more complex laser sensors and high resolution high speed cameras. Combinations of several cameras to build up 3D images of an object are also available.\nLimitations of a vision system.\nThere are always difficulties of integrated vision system to match the camera with the set expectations of the system, in most cases this is caused by lack of knowledge on behalf of the integrator or machine builder. Many vision systems can be applied successfully to virtually any production activity, as long as the user knows exactly how to set up system parameters. This set-up, however, requires a large amount of knowledge by the integrator and the number of possibilities can make the solution complex. Lighting in industrial environments can be another major downfall of many vision systems.\nVGR approaches.\nTypically, vision guidance systems fall into two categories; stationary camera mount, or robot arm-mounted camera. A stationary camera is typically mounted on a gantry or other structure where it can observe the entire robot cell area. This approach has the advantage of knowing its fixed position, providing a stable point of reference for all the activity within the cell. It has the disadvantage of additional infrastructure cost, and occasionally having its view obstructed by the robot arm's position. It also typically requires large image files (5 Mpixel or more) since the image must cover the entire work area.\nThese may be 2D or 3D cameras, although the vast majority of installations (2019) are using machine vision 2D cameras offered by companies such as Keyence, Basler, Sick, Datalogic, COGNEX and many others. Emerging players such as Leopard Imaging, Pickit3D, Zivid, and Photoneo are offering 3D cameras for stationary use. COGNEX recently acquired EnShape to add 3D capabilities to its lineup as well. 3D stationary mount cameras create large image files and point clouds that require substantial computing resources to process.\nA camera mounted on a robot arm has some advantages and disadvantages. Some 3D cameras are simply too large to be practical when mounted on a robot, but Pickit 3D's Xbox cameras and 2D cameras such as Robotiq's wrist camera are compact and/or light enough to not meaningfully affect available robot working payload. An arm mounted camera has a smaller field of view, and can operate successfully at lower resolution, even VGA, because it is only surveying a fraction of the entire work cell at any point in time. This leads to faster image processing times.\nHowever, arm mounted cameras, whether 2D or 3D, typically suffer from XYZ disorientation because they are continually moving and have no way of knowing the robot arm's position. The typical workaround is to interrupt each robot cycle long enough for the camera to take another image and get reoriented. This is visible in essentially all published videos of arm-mounted camera's performance, whether 2D or 3D, and can increase cycle times by as much as double what would otherwise be required.\nPickit 3D's Xbox camera has been arm-mounted for some applications. While capable of more complex 3D tasks such as bin picking, it still requires the stop-take-a-picture re-orientation mentioned above; it's 3D awareness does not help with that problem.\nVisual Robotics claims to eliminate this cycle interruption with their \"Vision-in-Motion\" capabilities. Their system combines a 2D imager with internal photogrammetry and software to perform 3D tasks at high speed, owing to the smaller image files. The company claims a pending patent covering techniques for ensuring the camera knows its location in 3D space without stopping to get reoriented, leading to substantially faster cycle times. While much faster than other 3D approaches, it is not likely to be able to handle the more complex 3D tasks a true stereo camera can. On the other hand, many 3D applications require relatively simple object identification easily supported by the technique. To date, their ability to visually pick objects in motion (e.g. items on a conveyor) using an arm-mounted camera appears to be unprecedented.\nVGR systems benefits.\nTraditional automation means serial production with large batch sizes and limited flexibility. Complete automation lines are usually built up around a single product or possibly a small family of similar products that can run in the same production line. If a component is changed or if a complete new product is introduced, this usually causes large changes in the automation process-in most cases new component fixtures are required with time-consuming setup procedures. If components are delivered to the process by traditional hoppers and vibrating feeders, new bowl feeder tooling or additional bowl feeder tops are required. It may be that different product must be manufactured on the same process line, the cost for pallets, fixtures and bowl feeders can often be a large part of the investment. Other areas to be considered are space constraints, storage of change parts, spare components, and changeover time between products.\nVGR systems can run side by side with very little mechanical setup; in the most extreme cases a gripper change is the only requirement, and the need to position components to set pick-up position is eliminated. With its vision system and control software, it is possible for the VGR system to handle different types of components. Parts with various geometry, can be fed in any random orientation to the system and be picked and placed without any mechanical changes to the machine, resulting in quick changeover times. Other features and benefits of VGR systems are:", "Engineering,_Manufacturing": 1.0000064373, "qwen": "Yes"}
{"id": "19345769", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=19345769", "title": "Quilt packaging", "text": "Quilt Packaging (QP) is an integrated circuit packaging and chip-to-chip interconnect packaging technology that utilizes “nodule” structures that extend out horizontally from the edges of microchips to make electrically and mechanically robust chip-to-chip interconnections. \nQP nodules are created as an integral part of the microchip using standard back end of the line semiconductor device fabrication techniques.  Solder is then electroplated on top of the nodules to enable the chip to chip interconnection with sub-micron alignment accuracy.\nSmall high yielding “chiplets” made from any semiconductor material (Silicon, Gallium Arsenide, Silicon Carbide, Gallium Nitride, etc.), can be “quilted” together to create larger multi-function meta-chip.  Thus, QP technology can integrate multiple chips with dissimilar technologies or substrate materials in planar, 2.5D and 3D configurations.\nRF Analog Performance.\nMultiple measured insertion loss on QP interconnects have been conducted on quilted chipsets with sets of homogeneous and heterogeneous semiconductor materials.  Radio frequency S-parameter measurements were made from DC to 220 GHz. QP interconnects have demonstrated less than 0.1 dB insertion loss from DC to 100 GHz between silicon and silicon chips, and less than 0.8 dB insertion loss up to 220 GHz between Silicon and Gallium Arsenide.\nDigital Performance.\nQP interconnects have a achieved 12 gigabit/sec (Gbps) bit-rate throughput with no distortion with 10 µm nodules on a 10 µm pitch on the edge of the chip.\nOptics/Photonics.\nPreliminary optical coupling loss simulations and measurements indicate that inter-chip coupling loss is < 6 dB for a gap of less than 4 µm.  Loss rapidly improves as the gap approaches zero, which is achievable with Quilt Packaging assembly tolerances.", "Engineering,_Manufacturing": 0.9999079704, "qwen": "Yes"}
{"id": "21265886", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=21265886", "title": "Precision glass moulding", "text": "Precision glass moulding is a replicative process that allows the production of high precision optical components from glass without grinding and polishing. The process is also known as ultra-precision glass pressing. It is used to manufacture precision glass lenses for consumer products such as digital cameras, and high-end products like medical systems. The main advantage over mechanical lens production is that complex lens geometries such as aspheres can be produced cost-efficiently.\nProcess.\nThe precision glass moulding process consists of six steps:\nThe process is executed on a specialized moulding machine, which precisely controls the temperature, travel, and force during the process. The tools used must withstand high temperatures and pressures, and need to be resistant to chemical interaction with the glass. The mold materials also have to be suitable for machining into the precise surface profiles.\nProcess chain.\nIn order to ensure the desired quality the parts are measured between each process step. Additionally, the parts are handled and transported carefully between the processing and metrology steps.\nTool and mould design.\nLens shapes.\nShape of optical element.\nPrecision glass moulding can be used to produce a large variety of optical form elements such as spheres, aspheres, free-form elements and array-structures.\nConcerning the curvature of the lens elements, the following statements can be drawn: Acceptable lens shapes are most bi-convex, plano-convex and mild meniscus shapes. Not unacceptable but hard to mould are bi-concave lenses, steep meniscus lenses, and lenses with severe features (e.g. a bump on a convex surface).\nIn general, plano-curved lenses are easier to mould than lenses with both sides curved since matching of flat faces is easier.\nMoulding concave forms with small centre thickness is difficult due to sticking of the moulded part to the mould occurring as a result of the different thermal expansion coefficients.\nFurthermore it is recommended to avoid undercuts and sharp edges. For the lens design it should be considered that the lens has to be mountable in measurement systems.\nShape of preforms.\nThe shape of the preform or \"blank\" needs to be chosen according to the geometry of the finished optical element. Possible preforms are spherical (ball), near spherical (gob), plano-plano, plano-convex, plano-concave, biconvex and biconcave blanks. Ball and gob-blanks do not have to be premachined whereas other preforms require grinding and polishing.\nThe following section describes basic traits of preform choice:\n“Used specifically for lenses with positive power: biconvex, plano-convex, and meniscus where the convex side is stronger than the concave side, this only works for a relatively small volume of material.”\n“As a lens changes to negative in power biconcave, plano-concave, and meniscus\nwhere the concave side is stronger, an alternative preform shape, plano-plano, is required\nfor the molding process. […] Relative to a formed preform an increase in cost is observed for the manufacturing of this type of preform.”\n“When the geometry of a lens extends beyond the volume range of a formed ball\npreform, a ground and polished ball preform is required. Used for lenses with positive\npower: biconvex, plano-convex, and meniscus: where the convex side is stronger, this\ngeometry allows for molding of lenses with larger total volume. […] Relative to a formed\npreform and a plano-plano preform, an increase in cost is observed for the manufacturing\nof this type of preform.”\n“The Lenslet preform is primarily for lenses with positive power, biconvex, planoconvex,\nand meniscus: where the convex side is the strongest surface. The use of this\ntype of preform allows for molding of the largest volume of glass at any given time in the\nmolding machines. The Lenslet is traditionally ground and polished to a near net shape of the final lens, and then pressed. [...] The cost associated with the manufacturing of the lenslet preform is the highest of all preform types.”\nPrecision gobs can be used as preforms for the production of aspherical lenses in a precision molding process. They are manufactured from a continuous glass melting process. The resulting precision gobs exhibit a very smooth firepolished surface with an excellent surface roughness and high volume accuracy.\nDimensions.\nThe dimensions of the optical elements that can be moulded depend on the size of the moulding machine.\nThe precision glass moulding process is not limited to small optics. For the right element geometry, it can enable economical production of aspheric lenses up to 60 mm in diameter and more than 20 mm thick.\nGeneral design recommendations:\nSize:\nRadius:\nOptical Surfaces:\nVolume:\nTolerances.\nAlthough the form, dimensional and positional tolerances that can be achieved in precision glass moulding are subject to a natural border, the values being achieved in practice strongly depend on the degree of control and experience in mould making and moulding. The table below gives an overview of achievable manufacturing tolerances in precision glass moulding at different companies.\nFor aspherical lenses, the design should be able to tolerate 0.010 mm of lateral shear between surfaces plus 5 micrometres Total Internal Reflection of wedge (across the part without considering the lateral shear) to be considered robust.\nSpecifications for aspheres:\nIndex drop.\nDue to the fast cooling after moulding, the part retains a small amount of residual stress. Consequently, the glass exhibits a small change in the refractive index which has to be considered in the optical design. A higher cooling rate corresponds to a larger decrease of the refractive index. A lower cooling rate could circumvent the index drop, but would be less cost-efficient\nGlass material.\nMany glasses can be used with PGM. However, there are some limitations:\nSo-called \"low-Tg-glasses\" with a maximum transition temperature of less than 550 °C have been developed in order to enable new manufacturing routes for the moulds. Mould materials such as steel can be used for moulding low-Tg-glasses whereas high-Tg–glasses require a high-temperature mould material, such as tungsten carbide.\nSubstrate materials.\nThe mould material must have sufficient strength, hardness and accuracy at high temperature and pressure. Good oxidation resistance, low thermal expansion and high thermal conductivity are also required.\nThe material of the mould has to be suitable to withstand the process temperatures without undergoing deforming processes. Therefore, the mould material choice depends critically on the transition temperature of the glass material. For low-Tg-glasses, steel moulds with a nickel alloy coating can be used. Since they cannot withstand the high temperatures required for regular optical glasses, heat-resistant materials such as carbide alloys have to be used instead in this case. In addition, mould materials include aluminium alloys, glasslike or vitreous carbon, silicon carbide, silicon nitride and a mixture of silicon carbide and carbon.\nA commonly used material in mould making is tungsten carbide. The mould inserts are produced by means of powder metallurgy, i.e. a sintering process followed by post-machining processes and sophisticated grinding operations. Most commonly a metallic binder (usually cobalt) is added in liquid phase sintering. In this process, the metallic binder improves the toughness of the mould as well as the sintering quality in the liquid phase to fully dense material.\nMoulds made of hard materials have a typical lifetime of thousands of parts (size dependent) and are cost-effective for volumes of 200-1000+ (depending upon the size of the part).\nMould manufacturing.\nThis article describes how mould inserts are manufactured for precision glass moulding.\nIn order to ensure high quality standards metrology steps are implemented between each process step.\nIn order to save the quality and enable an early warning in case of any problems between every single step there has to be a step of measurement and referencing. Besides that the time for transport and handling has to be taken into account in the planning of the process.\nMetrology and quality assurance.\nOnce process and tool have been developed, precision glass moulding has a great advantage over conventional\nproduction techniques. The majority of the lens quality characteristics are tool-bound. This means that lenses, which\nare pressed with the same tool and process, usually have only insignificantly small deviations. For example, an important characteristic of a lens is the form of the optical surface. In the case of aspherical lenses the measurement of optical surfaces is very difficult and connected to high efforts. Additionally, when working with tactile measurement systems there is always a risk that the optical surface might be scratched. For precision moulded lenses such measurements are only necessary for a small amount of sample lenses in order to qualify the tool. The series production can then be executed without further need for measurements. In this case, only the cleanliness of the optical surface has to be monitored. Another advantage is that the lens' center thickness can be estimated from the easily measurable edge thickness or by applying a contactless measurement system.\nProtective coatings.\nIn order to enhance the mould insert's lifetime, protective coatings can be applied. “The materials that have been selected for the antistick coatings can be divided into 5 groups including: (1) single layer carbides, nitrides, oxides and borides such as , and , (2) nitrides or carbides based gradient and multilayers, (3) nitrides based superlattice films, (4) amorphous carbon or diamond-like carbon and (5) precious metal based alloys”\nExperiments carried out by Ma et al. yield the following results:\n“The higher the temperature, the smaller the wetting angle between glass gob and substrate could be observed. This indicates that severe interface chemical reaction occurred and resulted in the loss of transparency in glass appearance. The wetting experiment in nitrogen ambient improved the sticking situation. The combination of chemically stable substrates and coatings, such as Sapphire (substrate) / GaN (film) and Glass (substrate) / (film) can achieve the best antistick propose. The precious metal films such as (Platinum, Iridium) coated on the ceramic substrates can effectively reduce the interface reaction between the glass and substrates.”\nAlthough is used as a standard coating material, it has the disadvantage of being expensive. Therefore, research activities aim at substituting with cheaper materials.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "21274518", "revid": "12396222", "url": "https://en.wikipedia.org/wiki?curid=21274518", "title": "Tube bending", "text": "Tube bending is any metal forming processes used to permanently form pipes or tubing. Tube bending may be form-bound or use freeform-bending procedures, and it may use heat supported or cold forming procedures.\nForm bound bending procedures like “press bending” or “rotary draw bending” are used to form the work piece into the shape of a die. Straight tube stock can be formed using a bending machine to create a variety of single or multiple bends and to shape the piece into the desired form. These processes can be used to form complex shapes out of different types of ductile metal tubing. Freeform-bending processes, like three-roll-pushbending, shape the workpiece kinematically, thus the bending contour is not dependent on the tool geometry.\nGenerally, round stock is used in tube bending. However, square and rectangular tubes and pipes may also be bent to meet job specifications. Other factors involved in the bending process are the wall thickness, tooling and lubricants needed by the pipe and tube bender to best shape the material, and the different ways the tube may be used (tube, pipe wires).\nIn 1995, Uk-based Unison Ltd developed the first three ‘all-electric’ tube bending machines with; 20mm, 40mm and 65mm tube capacity. The very first machine went into service in 1996 and is still in production.\nGeometry.\nA tube can be bent in multiple directions and angles. Common simple bends consist of forming elbows, which are 90° bends, and U-bends, which are 180° bends. More complex geometries include multiple two-dimensional (2D) bends and three-dimensional (3D) bends. A 2D tube has the openings on the same plane; a 3D has openings on different planes.\nA two plane bend or compound bend is defined as a compound bend that has a bend in the plan view and a bend in the elevation. When calculating a two plane bend, one must know the bend angle and rotation (dihedral angle).\nOne side effect of bending the workpiece is the wall thickness changes; the wall along the inner radius of the tube becomes thicker and the outer wall becomes thinner. To reduce this the tube may be supported internally and or externally to preserve the cross section. Depending on the bend angle, wall thickness, and bending process the inside of the wall may wrinkle.\nProcesses.\nTube bending as a process starts with loading a tube into a tube or pipe bender and clamping it into place between two dies, the clamping block and the forming die. The tube is also loosely held by two other dies, the wiper die and the pressure die.\nThe process of tube bending involves using mechanical force to push stock material pipe or tubing against a die, forcing the pipe or tube to conform to the shape of the die. Often, stock tubing is held firmly in place while the end is rotated and rolled around the die. Other forms of processing including pushing stock through rollers that bend it into a simple curve. For some tube bending processing, a mandrel is placed inside the tube to prevent collapsing. The tube is held in tension by a wiper die to prevent any creasing during stress. A wiper die is usually made of a softer alloy such as aluminum or brass to avoid scratching or damaging the material being bent.\nMuch of the tooling is made of hardened steel or tool steel to maintain and prolong the tool's life. However, when there is a concern of scratching or gouging the work piece, a softer material such as aluminum or bronze is utilized. For example, the clamping block, rotating form block and pressure die are often formed from hardened steel because the tubing is not moving past these parts of the machine. The pressure die and the wiping die are formed from aluminum or bronze to maintain the shape and surface of the work piece as it slides by.\nPipe bending machines are typically human powered, pneumatic powered, hydraulic assisted, hydraulic driven, or electric servomotor.\nPress bending.\nPress bending is probably the first bending process used on cold pipes and tubing. In this process a die in the shape of the bend is pressed against the pipe forcing the pipe to fit the shape of the bend. Because the pipe is not supported internally there is some deformation of the shape of the pipe, resulting in an oval cross section. This process is used where a consistent cross section of the pipe is not required. Although a single die can produce various shapes, it only works for one size tube and radius.\nRotary draw bending.\nRotary draw bending (RDB) is a precise technology, since it bends using tooling or \"die sets\" which have a constant center line radius (CLR), alternatively indicated as mean bending radius (Rm). Rotary draw benders can be programmable to store multiple bend jobs with varying degrees of bending. Often a positioning index table (IDX) is attached to the bender allowing the operator to reproduce complex bends which can have multiple bends and differing planes.\nRotary draw benders are the most popular machines for use in bending tube, pipe and solids for applications like: handrails, frames, motor vehicle roll cages, handles, lines and much more. Rotary draw benders create aesthetically pleasing bends when the right tooling is matched to the application.\nCNC rotary draw bending machines can be very complex and use sophisticated tooling to produce severe bends with high quality requirements.\nThe complete tooling is required only for high-precision bending of difficult-to-bend tubes with relatively large OD/t (diameter/thickness) ratio and relatively small ratio between the mean bending radius Rm and OD. The use of axial boosting either on the tube free end or on the pressure die is useful to prevent excessive thinning and collapse of the extrados of the tube. The mandrel, with or without ball with spherical links, is mostly used to prevent wrinkles and ovalization. For relatively easy bending processes (that is, as the difficulty factor BF decreases), the tooling can be progressively simplified, eliminating the need for the axial assist, the mandrel, and the wiper die (which mostly prevents wrinkling). Furthermore, in some particular cases, the standard tooling must be modified in order to meet specific requirements of the products.\nRoll bending.\nDuring the roll bending process the pipe, extrusion, or solid is passed through a series of rollers (typically three) that apply pressure to the pipe gradually changing the bend radius in the pipe. The pyramid style roll benders have one moving roll, usually the top roll. Double pinch type roll benders have two adjustable rolls, usually the bottom rolls, and a fixed top roll. This method of bending causes very little deformation in the cross section of the pipe. This process is suited to producing coils of pipe as well as long gentle bends like those used in truss systems.\nThree-roll push bending.\nThree-roll push bending (TRPB) is the most commonly used freeform-bending process to manufacture bending geometries consisting of several plane bending curves. Nevertheless, 3D-shaping is possible. The profile is guided between bending-roll and supporting-roll(s), while being pushed through the tools. The position of the forming-roll defines the bending radius. The bending point is the tangent-point between tube and bending-roll. To change the bending plane, the pusher rotates the tube around its longitudinal axis. Generally, a TRPB tool kit can be applied on a conventional rotary draw bending machine. The process is very flexible since with a unique tool set, several bending radii values Rm can be obtained, although the geometrical precision of the process is not comparable to rotary draw bending. \nBending contours defined as spline- or polynomial-functions can be manufactured.\nSimple three-roll bending.\nThree roll bending of tubes and open profiles can also be performed with simpler machines, often semi-automatic and non CNC controlled, able to feed the tube into the bending zone by friction. These machines have often a vertical layout, i.e. the three rolls lie on a vertical plane.\nInduction bending.\nAn induction coil is placed around a small section of the pipe at the bend point. It is then induction heated to between 800 and 2,200 degrees Fahrenheit (430 and 1,200 C). While the pipe is hot, pressure is placed on the pipe to bend it. The pipe can then be quenched with either air or water spray or be cooled against ambient air.\nInduction bending is used to produce bends for a wide range of applications, such as (thin walled) pipe lines for both the upstream and down stream and on- and off shore segments of the petrochemical industry, large radius structural parts for the construction industry, thick walled, short radius bends for the power generating industry and city heating systems.\nBig advantages of induction bending are:\nPacking.\nIce packing.\nThe pipe is filled with a water solution, frozen, and bent while cold. The solute (soap can be used) makes the ice flexible. This technique is used to make trombones.\nPitch packing.\nA similar techniques using pitch was formerly used, but discontinued because the pitch was hard to clean out without excessive heat.\nSand-packing/hot-slab forming.\nIn the sand packing process the pipe is filled with fine sand and the ends are capped. The filled pipe is heated in a furnace to or higher. Then it is placed on a slab with pins set in it, and bent around the pins using a winch, crane, or some other mechanical force. The sand in the pipe minimizes distortion in the pipe cross section.\ns.\nA mandrel is a steel rod or linked ball inserted into the tube while it is being bent to give the tube extra support to reduce wrinkling and breaking the tube during this process. The different types of mandrels are as follows.\nIn production of a product where the bend is not critical a plug mandrel can be used. A form type tapers the end of the mandrel to provide more support in the bend of the tube. When precise bending is needed a ball mandrel (or ball mandrel with steel cable) should be used. The conjoined ball-like disks are inserted into the tubing to allow for bending while maintaining the same diameter throughout. Other styles include using sand, cerrobend, or frozen water. These allow for a somewhat constant diameter while providing an inexpensive alternative to the aforementioned styles.\nPerformance automotive or motorcycle exhaust pipe is a common application for a mandrel.\nBending springs.\nThese are strong but flexible springs inserted into a pipe to support the pipe walls during manual bending. They have diameters only slightly less than the internal diameter of the pipe to be bent. They are only suitable for bending soft copper pipe (typically used in household plumbing) or PVC pipe.\nThe spring is pushed into the pipe until its center is roughly where the bend is to be. A length of flexible wire can be attached to the end of the spring to facilitate its removal. The pipe is generally held against the flexed knee, and the ends of the pipe are pulled up to create the bend. To make it easier to retrieve the spring from the pipe, it is a good idea to bend the pipe slightly more than required, and then slacken it off a little. Springs are less cumbersome than rotary benders, but are not suitable for bending short lengths of piping when it is difficult to get the required leverage on the pipe ends.\nBending springs for smaller diameter pipes (10 mm copper pipe) slide over the pipe instead of inside.", "Engineering,_Manufacturing": 1.0000042915, "qwen": "Yes"}
{"id": "21287147", "revid": "42342156", "url": "https://en.wikipedia.org/wiki?curid=21287147", "title": "Printed Circuit Corporation", "text": "Printed Circuit Corporation (PCC) was founded in 1961 and was a contract printed circuit board manufacturer located in Woburn, Massachusetts. (SIC Code 3672). PCC provided its products to companies in the electronics, instrumentation, medical, telecommunication, and automotive industries. The majority of the boards produced were multilayer (4, 6, 8, or 10-layer).\nIn 1995, the environmental advances made by the firm were highlighted in a joint study by The Massachusetts Toxics Use Reduction Institute in conjunction with the University of Massachusetts Lowell.\nIn 2001, PCC was featured on an ABC-TV business news show called Business Now. The show featured the technology that the company used and the management disciplines that allowed it to compete effectively in the world PWB market.\nPeter Sarmanian was the founder and CEO of Printed Circuit Corporation. Sarmanian's contributions to the PWB industry as a whole have been recognized by the IPC on an annual basis.\nCompany history.\nPeter Sarmanian started Printed Circuit Corporation in 1961 during the early days of the computer industry. Sarmanian was pursuing an undergraduate technical degree at Northeastern University after having returned from service in the Korean War. His first significant production contracts were to manufacture printed circuit boards for the technology innovators of the 1960s - early minicomputer companies like RCA Computer Systems, Digital Equipment Corporation, and Data General Corporation.\nSarmanian was a pioneer in the electro-chemical production of printed circuit boards. The new process offered far greater reliability for the printed circuit boards and far higher density (chips and circuitry per square inch) for packaging components.\nWhen Sarmanian launched the company, most computer and electronics manufacturers were fabricating their own boards. Independent suppliers, however, became increasingly efficient and were proving a more cost-effective solution for a broad range of printed circuit board applications. Likewise, computer and electronics manufacturers became more comfortable using suppliers for key electronic components, including printed circuit boards. Reductions in time to market, engineering/prototyping costs, and manufacturing ramp-up costs were being demonstrated by these suppliers to win business. In 1979, 40% of all rigid printed circuit board fabrication was being outsourced to suppliers like PCC. By 1989, that figure was about 60%, and by 1995, 80%. By 2001, 98% of all printed circuit board production was going to external suppliers. Industry analysts placed total bookings for printed circuit board production worldwide at approximately $30 billion in 2000, with the US market comprising about a third of that dollar volume.\nSarmanian built a profitable company with approximately $30 million a year in revenue at its peak in 2000, and a fabrication plant on Route 128 outside of Boston. At the time, he had 240 employees working two full shifts a day, and sometimes, another half shift for limited production of new prototype boards.\nSarmanian died in July 2001 following a bout with cancer. The company filed for reorganization shortly thereafter, then was acquired by Manchester, NH-based fabricator Electropac in October 2002.\nPrinted Circuit Corporation's business approach.\nPCC had traditionally operated in the mid-range segment, providing boards to New England-based minicomputer companies. Sarmanian bought state-of-the-art equipment to keep pace with the industry, but he always did it as a follower. At the beginning of the 1980s, Sarmanian saw that volumes in the low-end were beginning to explode and decided to diversify. By 1995, only 50% of PCC's revenues came from its traditional mid-range customers; the other 50% came from low-end consumer electronics manufacturers. By 1995 his company was a $20 million a year business. However, this low-end high-volume strategy got the company into financial trouble when the market for video game cartridges for the Atari and Intellivision systems collapsed.\nBy the early 1980s, offshore manufacturers had started low complexity, high volume fabrication. By the end of the decade, they dominated it. In this semi-automated, high volume process, the offshore producers were able to quote substantially lower prices due to cheap labor. By 1995, the consumer electronics manufacturers had moved virtually all their business to Asian fabricators. Because of this foray into the low-end, by 1995 PCC's profits had declined 90%. New management was brought in during 1996 and 1997 to help turn the company around.\nNew management shed the unprofitable low-end business to refocus on the mid- range, more technologically complex segment of the market. These changes were made in time to capture some explosive growth. Historically, the PCB market had grown about 6% a year, but from 1995-2000 it grew at 10%. By 2000, the company's sales had increased to $30 million. Laser drilling, better solder masking for finishing printed circuitry, and semi-automated systems for electrical testing of finished boards were the major improvements needed to get to industry parity.\nPCC named Glen Kashgegian president and COO in 2000.\nIn June 2001, Printed Circuit Corp. acquired the circuit board fabrication business of CPC in Randolph, MA.\nThe End of PCC.\nAmid the tech recession of 2001–03, the company failed to adjust as customers migrated to lower cost products from China, and filed for reorganization in September 2002. The company then was acquired by Manchester, NH-based fabricator Electropac in October 2002.\nUltimately, as the North American Printed Circuit market continued to shrink and consolidate, Electropac closed their business and sold certain assets to another competitor, located in Nashua NH, named Mass Design.\nEnvironmental Battles.\nIn 1990, the company was fined $407,835 for allegedly violating state sewer regulations 60 times over two years and ignoring orders to stop. The penalty was the third-largest in the history of the Massachusetts Water Resources Authority at the time.", "Engineering,_Manufacturing": 0.9978502989, "qwen": "Yes"}
{"id": "21290040", "revid": "1133966642", "url": "https://en.wikipedia.org/wiki?curid=21290040", "title": "Arbor milling", "text": "Arbor milling is a cutting process which removes material via a multi-toothed cutter. An arbor mill is a type of milling machine characterized by its ability to rapidly remove material from a variety of materials. This milling process is not only rapid but also versatile.\nProcess Schematic.\nThis process progressively makes a surface to the user's specifications as the material is moved against the milling tool or the workpiece stays stationary while the arbor milling cutter moves across it to provide the desired shape. There are two types of milling that involve the directional movement of the workpiece, conventional and climb. If the workpiece is moving the opposite direction of the tool rotation this is called conventional milling. If the workpiece is moving the same direction as the tool rotation, this is called climb milling.\n\nSetup and Equipment.\nArbor milling is commonly performed on a horizontal milling machine. The tool is mounted on an arbor/mandrel (like an axle) that is suspended between the spindle and arbor support. This type of machine allows the tool to be placed in numerous positions in relation to the workpiece.\nWorkpiece Materials.\nThe workpiece involved in arbor milling can be a flat material or a shaped material: either one can be worked with desirable results. The hardness of the materials milled should be no harder than Rockwell C25(Rockwell scale), but workpieces harder than this can be successfully milled. Materials with good or excellent machinability include aluminum, brass, mild steel, cast iron, and thermoset plastics. Though initially ductile, stainless steel tends to work harden and thus has only a fair compatibility with this milling process (though it is in the feasible range).\nTooling Materials.\nAlthough high speed tool steel has been used in the past it is quickly being replaced by carbide, ceramic, or diamond tooling. Because carbide inserts are long lasting and easily replaced, they lend themselves to high production. Ceramic tools are brittle but can withstand high temperatures. This makes high speed machining possible. Diamond tools are used to achieve a superior surface finish (though they can only be used on non-ferrous materials).\nTolerances and Surface Finish.\nIn most applications, tolerances can be held within ±0.005 in. For precision application, tolerances can be held within ±0.001 in. It is possible to have a surface finish range of 32 to 500 microinches, but typically the range is 63 to 200 microinches. Finish cuts will generate surfaces near 32 to 63 microinches, roughing cuts near 200 microinches.\nTool Styles and Possibilities.\nThe most common tool styles used in arbor milling are: double angle, form relived, plane, and staggered tooth Among many other tool styles. The double angle milling cutter can make a wide variety of V shaped cuts with straight surfaces in the material. A form relieved milling cutter can produce U shaped cuts with curved surfaces, unlike the double angle cutter, into the material. A plane milling cutter can produce surfaces similar to a planer but can make varying contours across the material. A staggered tooth milling cutter can produce a rectangular groove in the material at varying depths and widths. The cutters can be stacked to mill combined profiles. The typical width of cuts made by arbor milling range from 0.25 in to 6 in, and the typical depths range from 0.02 in to 0.05 in.\nEffects on Work Material Properties.\nMechanical properties of the workpiece may be affected with a built-up edge or dull tool. Arbor Milling can create an untempered martensitic layer on the surface of heat-treated alloy steels, about 0.001 in thick. Other materials are affected very little by arbor milling.\nProcess Conditions.\nShown are the suggested ranges for cutting speeds and feed rates using high speed tool steel under dry cutting conditions at a 0.015 in depth of cut. Generally cutting speeds are lower for hard materials, higher for soft materials. Both cutting speeds and feed rates can be substantially increased when coolants are used and carbide tooling is substituted for steel tooling.\nTypical Speeds and Feeds\nLubrication and Cooling.\nDue to high cutting speeds a cutting fluid is required to lubricate and cool the tool and workpiece. The fluids can increase tool life, cutting speeds, and the quality of the finished surface. There are three common cutting fluids: mineral, synthetic, and water-soluble oils. These fluids can be applied by spraying, misting, or flooding the workpiece.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "30475108", "revid": "43558034", "url": "https://en.wikipedia.org/wiki?curid=30475108", "title": "Equipment service management and rental", "text": "Equipment service management and rental (ESM&R) refers to equipment services management throughout the heavy equipment life cycle. Increased competition and slim margins in heavy equipment sales and rental place a heavy burden on manufacturers, dealers, rental companies and service businesses to improve their service performance. Improving service in these conditions is critical to maintaining margins and growing profitability.\nThe ESM&R approach provides an integrated view of the heavy equipment business. Thus manufacturers, dealers, suppliers, rental and services business can improve the value their customers derive from their equipment and subsequently improve their own profitability and reduce cost at the same time. Collaboration is a critical factor in the equipment supply chain.\nEquipment companies must have two fundamentals in place of operational control of service operations on the one hand and equipment intelligence on the other. (1) This enables companies to move to proactive service approaches and make better business decisions. To instill these two fundamentals, service organizations are adopting equipment service management processes and tools.\nHeavy equipment life-cycle.\nThe ESM&R approach directly links to the concept of the equipment life-cycle which demands continuous control and a historical record – from the initial forecasting and sale of the equipment, through to shipping, renting, servicing, overhaul and final disposal. Thus heavy equipment, just like any product life-cycle has its own life-cycle. The main stages of the heavy equipment life-cycle are:\nReferences.\n\"Asset Management Excellence: Optimizing Equipment Life-cycle Decisions\" by Normand Champigny, Andrew K.S. Jardine, John D. Campbell, Taylor & Francis USA, 2008, ", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "26703961", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=26703961", "title": "Design change", "text": "A design change is the modification conducted to the product. It can happen at any stage in the product development process.\nThe design changes that happen early in the design process are less expensive when compared to those that take place after it is introduced into full-scale production. The cost of the change increases with its development time. Fundamentally, the design changes can be classified into pre production and post production design changes. The pre-production changes can happen in the conceptual design stage, prototype stage, detailing stage, testing stage. The post -production stage change will happen almost immediately the product is introduced into the production. This might be due to several reasons such as market response, design faults uncovering, design mistakes, not meeting customer requirements, so on and so forth. One of the tools to minimize this type of design change is House of Quality.", "Engineering,_Manufacturing": 0.9998160005, "qwen": "Yes"}
{"id": "43955598", "revid": "32381689", "url": "https://en.wikipedia.org/wiki?curid=43955598", "title": "Door control unit", "text": "In automotive electronics, a door control unit (DCU) is a generic term for an embedded system that controls a number of electrical systems associated with an advanced motor vehicle. A modern motor vehicle contains a number of ECUs (electronic control units), and the door control unit (DCU) is one of the minor ones.\nThe door control unit is responsible for controlling and monitoring various electronic accessories in a vehicle's door. Since most of the vehicles have more than one door, DCUs may be present in each door separately, or a single centralised one provided. A DCU associated with the driver's door has some additional functionalities. This additional features are the result of complex functions like locking, driver door switch pad, child lock switches, etc., which are associated with the driver's door. In most of the cases driver door module acts as a master and others act as slaves in communication protocols.\nFeatures controlled by door control units.\nIn some advanced motor vehicles, luxury features like puddle lamps and BLIS (Blind spot Indicator System) are also supported by DCUs.", "Engineering,_Manufacturing": 0.9982213974, "qwen": "Yes"}
{"id": "1628092", "revid": "15951685", "url": "https://en.wikipedia.org/wiki?curid=1628092", "title": "Glass tube", "text": "Glass tubes are mainly cylindrical hollow-wares. Their special shape combined with the huge variety of glass types (like borosilicate, flint, aluminosilicate, soda lime, lead or quartz glass), allows the use of glass tubing in many applications. For example, laboratory glassware, lighting applications, solar thermal systems and pharmaceutical packaging to name the largest.\nIn the past, scientists constructed their own laboratory apparatus prior to the ubiquity of interchangeable ground glass joints. Today, commercially available parts connected by ground glass joints are preferred; where specialized glassware are required, they are made to measure using commercially available glass tubes by specialist glassblowers. For example, a Schlenk line is made of two large glass tubes, connected by stopcocks and smaller glass tubes, which are further connected to plastic hoses.\nIndustrial Relevance.\nCompared to other materials like plastics the importance of cylindrical half-finished products in glass is high. Main reasons are the difficulty associated with 3-d forming of glass in general. In order to create hollow objects from glass the cylinder shape is a natural starting material.\nCylindrical glass tubes have:\n• the lowest surface area and most compact design\n• highest mechanical strength against pressure and impact\n• automated further processing due to symmetry.\nCompared to moulded glass where the process of tube drawing achieves:\n• better optical clarity\n• more homogeneous distribution of wall thickness\n• higher precision or volume and geometry in general\nHistory.\nUntil the 19th century glass tubes were exclusively produced by mouth blowing, thus discontinuously manufactured from a batch or a glass melt. In 1912, E. Danner (Libbey Glass Company) developed the first continuous tube drawing process in the US, which works in horizontal direction. In 1918 he received a patent. In 1929 a vertical drawing process was developed by L. Sanches-Vello in France.\nManufacturing Process.\nGlass tubes are produced in various types of glass and in diameters ranging from a few millimeters to several centimeters. In most production processes, an \"infinitely long\" glass tube is drawn directly from the melt, from which approximately 1.5 m long pieces are chopped off after passing a roller track up to the drawing machine.\nThe three common methods differ regarding the drawing direction:\nDrawing direction horizontal.\nDanner process.\nIn the Danner process, the molten glass runs from the feeder as a belt onto an obliquely downwardly inclined, rotating ceramic hollow cylinder, the Danner pipe. Through the hollow pipe, compressed air is blown to prevent the glass tube from collapsing. \nAt the tip of the pipe the so-called drawing onion is formed, from which the glass tube is drawn off in the free sag on a horizontal pulling line.\nIf the drawing speed is kept constantly, an increase in the blow pressure causes larger diameters and smaller wall thicknesses;\nWith this method, tube diameters between 2 and 60 mm can be realized:\nVello process.\nIn the Vello process, the glass runs through an annular opening from the bottom of the feeder. This opening is formed between the round outlet nozzle of the feeder and a height-adjustable hollow needle (also a mandrel). Here, the tube is \"inflated\" with compressed air as well. The glass tube which initially emerges in the vertical direction is then deflected into the horizontal position in the free sag.\nThe nozzle mandrel is adjusted off the center of the drawing nozzle in order to produce a constant wall thicknesses after bending.\nWith this method, tube diameters between 1.5 and 70 mm can be generated; The throughput is higher than it would have been with the Danner method. Furthermore, it is possible here to use glasses with highly volatile components, such as borates (borosilicate glass) and lead oxides (lead glass), since the temperatures at the drawing nozzle are lower than in the Danner muffle.\nWithout a needle, glass rods can also be produced, whereby the diameter being adjusted via the nozzle as well as the drawing speed. Due to the vertical glass exit, down-draw processes are sporadically also listed under the general term \"Vello\", although there is no forcible deflection into the horizontal.\nDanner and Vello processes are used for the production of thin-walled glass tubes of relatively small diameter, with throughputs of up to 55 tonnes per day.\nThe world record for the longest ever continuously drawn tube glass in one piece is 10 m hold by SCHOTT Tubing.\nDrawing direction downwards (down-draw).\nThe down-draw method is, in principle, the same as the Vello method, although here the glass tube is not deflected but is pulled off in the vertical direction.\nIn the down-draw, the current world record is held by SCHOTT Tubing with 460 mm. The achievable wall thicknesses for large outer diameters above 250 mm is about 10 mm. Larger wall thicknesses of up to 15 mm are possible for smaller outer diameters only. For borosilicate glass (35 mm Durchmesser) a drawing speed of 0.3 m/min can be achieved.\nDrawing direction vertically upwards (vertical drawing).\nHere, the glass tube is not formed by a mandrel but is drawn off from the free bath surface. A nozzle protrudes from below into a drawing nozzle, via which the air is blown into the glass tube. The nozzle also holds the drawing onion so that it does not move out laterally. \nSince the quality and drawing speed achieved during the vertical tube drawing process are relatively low, this process has nowadays almost no practical significance.\nFurther procedures.\nGlass tubes with very large diameters (20 bis 100 cm), as required for plants of the chemical industry, are produced by centrifugation or blowing. However, only the production of relatively short tube sections of up to one meter, so-called tube shots, is possible.\nModifying.\nMany glass tubing can be used right away for example for pneumatic conveying systems, lighting, photobioreactors or as an architectural item. However, modifying of glass tubing is quite common and indespendsable for applications like laboratory glass, pharma packaging, and diode encapsulants. Here, the glass tubing needs to be e.g. cut, bended, or even converted into another shape (compare vial, syringes etc.). Mainly, this is done by applying heat to the sample and/or use a mechanic forming tool.\nAlthough modifying glass tubing is no longer an essential laboratory technique, many are still familiar with the basic methods. A glass cutter is used to break pieces of glass tubing into smaller pieces. Freshly cut edges are flame polished before use to remove the rough edge. Glass tubing can be bent by heating evenly over a Bunsen flame to red heat. Hose barbs can be added to tubing, giving a better grip and seal for attaching plastic or rubber tubing.\nApplications.\nGlass tubes are not only produced in round shapes but also in various other shapes such as rectangular, triangular and star-like shape. \nGlass tubes, rods and profiles can be made from different glass types. They find use in a variety of markets such as pharmaceuticals, industrial and environmental technology as well as electronics. Glass tubes are processed in:\nManufacturers.\nThere are several companies concentrating on the production of glass tubes made from special glass types. By using a special glass type with particular properties the glass tubes can be fit for a variety of applications. Some well-known manufacturers of glass tubes are:", "Engineering,_Manufacturing": 0.9994101524, "qwen": "Yes"}
{"id": "40495190", "revid": "2304267", "url": "https://en.wikipedia.org/wiki?curid=40495190", "title": "Turret punch", "text": "A turret punch or turret press is a type of punch press used for metal forming by punching.\nPunching, and press work in general, is a process well suited to mass production. However the initial tooling costs, of both the machine and the job-specific press tool, are high. This limits punch work from being used for much small-volume and prototype work. A turret punch is one way of addressing this cost. The tooling of a turret punch uses a large number of standard punch tools: holes of varying sizes, straight edges, commonly-used notches or mounting holes. By using a large number of strokes, with several different tools in turn, a turret press may make a wide variety of parts without having to first make a specialised press tool for that task. This saves both time and money, allowing rapid prototyping or for low volume production to start without tooling delays.\nA typical CNC turret punch has a choice of up to 60 tools in a \"turret\" that can be rotated to bring any tool to the punching position. A simple shape (e.g., a square, circle, or hexagon) is cut directly from the sheet. A complex shape can be cut out by making many square or rounded cuts around the perimeter. As a press tool requires a matching punch and die set, there are two corresponding turrets, above and below the bed, for punch and die. These two turrets must rotate in precise synchronisation and with their alignment carefully maintained. Several punches of identical shape may be used in the turret, each one turned to a different angle, as there is usually no feature to rotate the sheet workpiece relative to the tool.\nA punch is less flexible than a laser for cutting compound shapes, but faster for repetitive shapes (for example, the grille of an air-conditioning unit). Some units combine both laser and punch features in one machine.\nMost turret punches are CNC-controlled, with automatic positioning of the metal sheet beneath the tool and programmed selection of particular tools. A CAM process first converts the CAD design for the finished item into the number of individual punch operations needed, depending on the tools available in the turret.\nThe precise load-out of tools may change according to a particular job's needs. The CAD stage is also optimised for turret punching: an operation such as rounding a corner may be much quicker with a single chamfered cut than a fully rounded corner requiring several strokes. Changing an unimportant dimension such as the width of a ventilation slot may match an available tool, requiring a single cut, rather than cutting each side separately. CAD support may also manage the selection of tools to be loaded into the turret before starting work.\nAs each tool in a turret press is relatively small, the press requires little power compared to a press manufacturing similar parts with a single press stroke. This allows the tool to be lighter and sometimes cheaper, although this is offset by the increased complexity of the turret and sheet positioning. Turret punches can operate faster per stroke than a heavier tool press, although of course many strokes are required. A turret punch can achieve 600 strokes per minute.\nThe most sophisticated recent machines may also add facilities for forming and bending, as well as punch cutting. Although unlikely to replace a press brake for box making, the ability to form even small lugs may turn a two machine process into a one machine process, reducing materials handling time.\nManual punches.\nManual turret punches have also been used. These are C frame presses, usually with a rack-actuated ram. There is no CNC, for either sheet positioning or tool changing. Using such a manual press requires great familiarity, as the correct tool must be selected from the turret each time for every one of the many press operations performed. Such manual presses are rarely found, but they have their place in labour-intensive tasks such as hand-worked sheetmetal shops, making such products as custom car bodywork. They are often used in conjunction with other highly skilled artisan processes such as an English wheel.", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "5621338", "revid": "43767367", "url": "https://en.wikipedia.org/wiki?curid=5621338", "title": "Raster passes", "text": "Raster passes are the most basic of all machining strategies for the finishing or semi-finishing of a part during computer-aided manufacturing (CAM). In raster passes machining the milling cutter moves along curves on the cutter location surface (CL surface) obtained by intersecting the CL surface with vertical, parallel planes. Many CAM systems implement this strategy by sampling cutter location points on these curves by calculating intersection points of the CL surface and as many vertical lines as needed to approximate the curve to the desired accuracy.", "Engineering,_Manufacturing": 0.9999848604, "qwen": "Yes"}
{"id": "5621528", "revid": "18144528", "url": "https://en.wikipedia.org/wiki?curid=5621528", "title": "Heijunka box", "text": "A heijunka box is a visual scheduling tool used in heijunka, a method originally created by Toyota for achieving a smoother production flow. While heijunka is the smoothing of production, the heijunka box is the name of a specific tool used in achieving the aims of heijunka.\nThe heijunka box is generally a wall schedule which is divided into a grid of boxes or a set of 'pigeon-holes'/rectangular receptacles. Each column of boxes representing a specific period of time, lines are drawn down the schedule/grid to visually break the schedule into columns of individual shifts or days or weeks. Coloured cards representing individual jobs (referred to as kanban cards) are placed on the heijunka box to provide a visual representation of the upcoming production runs.\nThe heijunka box makes it easy to see what type of jobs are queued for production and for when they are scheduled. Workers on the process remove the kanban cards for the current period from the box in order to know what to do. These cards will be passed to another section when they process the related job.\nImplementation.\nThe Heijunka box allows easy and visual control of a smoothed production schedule.\nA typical heijunka box has horizontal rows for each product. It has vertical columns for identical time intervals of production. In the illustration on the right, the time interval is thirty minutes. Production control kanban are placed in the pigeon-holes provided by the box in proportion to the number of items to be built of a given product type during a time interval.\nIn this illustration, each time period builds an A and two Bs along with a mix of Cs, Ds and Es. What is clear from the box, from the simple repeating patterns of kanbans in each row, is that the production is smooth of each of these products.\nThis ensures that production capacity is kept under a constant pressure thereby eliminating many issues.", "Engineering,_Manufacturing": 0.9998390675, "qwen": "Yes"}
{"id": "27050574", "revid": "1028649", "url": "https://en.wikipedia.org/wiki?curid=27050574", "title": "Die defect", "text": "A die defect is a unique and unintentional flaw in a coin die and is created through excessive use or polishing of the die. A die bearing such a defect is occasionally referred to as a defective die. Generally, and depending upon the magnitude of the defect, coins that are produced from these dies are considered error coins. Also, the term encompasses a wide variety of design errors that were engraved into the die originally and were slipped into circulation before the incorrect design was discovered.\nTypes.\nDie crack.\nA die crack occurs when a die, after being subjected to immense pressure during the minting process, cracks, causing a small gap in the die. If this damaged die continues to produce coins, the metal will fill into the crack, thus revealing a raised line of metal in the finished coin. Specimens with more prominent die cracks can command a high premium and are valued greatly by some collectors. However, less obvious errors are quite common, especially in the 50 States Commemorative Quarter Program, yielding a lower value.\nCud.\nA cud on a coin is a damaged area resembling a blob at the edge of the coin. Cuds result from a piece of the perimeter of the die breaking away. They can be any shape depending on the shape of the piece that broke off the die. ", "Engineering,_Manufacturing": 0.992430985, "qwen": "Yes"}
{"id": "10603516", "revid": "39203", "url": "https://en.wikipedia.org/wiki?curid=10603516", "title": "Edgeline printing", "text": "Edgeline printing is a printing technology based on ink jet printing. In the case of traditional ink jet printers, the tiny matchbox size print head moves back and forth. This has inherent delay and requires two dimensional movement: (a) movement of print head; and (b) movement of paper. These movements are one of the reasons for the time lag in the ink jet printing.\nIn the case of edgeline printing technology, the print head is wide enough to cover the size of the printing paper supported in the printer. The print head has ink jet nozzles for the full length of the print head. By this arrangement the print head need not move and the paper movement is the only required movement.\nThe technology was developed by Hewlett-Packard, and was used in the Photosmart Express Station pe1000 retail photo kiosks, Photosmart pm1000 Microlab printer, and CM8060/8050 Color MFP office printers.\nPhoto lab printers.\nPM1000 Microlab printer.\nThe PM1000 Microlab printer prints a 6x4 photo in five passes past a set of three fixed print heads. While the print head is large enough to cover the whole photo the 5 passes prevents pooling by putting down too much ink at once and enables the printer to hide faulty nozzles. This printer can print a photo in 5 seconds.\nPE1000 Photosmart Express.\nThe Photosmart Express Station is basically a PM1000 print engine with a user friendly kiosk mounted on top designed for customers to print photos quickly from memory cards or other sources.\nOffice printers.\nCM8050 / CM8060.\nThe CM8050 and CM8060 are high volume office printers that can print an entire A4/Letter page in a single pass, or an A3 page in two passes. To achieve this it uses two carriages with three print heads each, each print head containing 10,560 nozzles. This enables the printer to print up to 71 pages per minute in black and color (CM8060) and 57 ppm (CM8050).", "Engineering,_Manufacturing": 0.999736011, "qwen": "Yes"}
{"id": "69157828", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=69157828", "title": "1999 Nigerian House of Representatives elections in Taraba State", "text": "The 1999 Nigerian House of Representatives elections in Taraba State was held on February 20, 1999, to elect members of the House of Representatives to represent Taraba State, Nigeria.\nResults.\nBali/Gassol.\nPDP candidate Dahiru Bako Gassol won the election, defeating other party candidates.\nJalingo/Yorro/Zing.\nPDP candidate Alhassan Al-Gaddas won the election, defeating other party candidates.\nKarim Lamido/Lau/Ardo-Kola.\nPDP candidate Tauru T. Hanin won the election, defeating other party candidates.\nSardauna/Gashaka/Kurmi.\nPDP candidate Kuriya Tafarki Auta won the election, defeating other party candidates.\nTakuma/Donga/Ussa.\nAPP candidate Abdulaziz Tanko won the election, defeating other party candidates.\nWukari/Ibi.\nPDP candidate Dantani Sunsuwa won the election, defeating other party candidates.", "Engineering,_Manufacturing": 0.9997435212, "qwen": "Yes"}
{"id": "69157892", "revid": "29463730", "url": "https://en.wikipedia.org/wiki?curid=69157892", "title": "2003 Nigerian House of Representatives elections in Taraba State", "text": "The 2003 Nigerian House of Representatives elections in Taraba State was held on April 12, 2003, to elect members of the House of Representatives to represent Taraba State, Nigeria.\nResults.\nBali/Gassol.\nPDP candidate Dahiru Bako Gassol won the election, defeating other party candidates.\nJalingo/Yorro/Zing.\nPDP candidate Alhassan Al-Gaddas won the election, defeating other party candidates.\nKarim Lamido/Lau/Ardo-Kola.\nPDP candidate Khamin Taurus won the election, defeating other party candidates.\nSardauna/Gashaka/Kurmi.\nPDP candidate S.M. Nguroje won the election, defeating other party candidates.\nTakuma/Donga/Ussa.\nPDP candidate Emmanuel Bwacha won the election, defeating other party candidates.\nWukari/Ibi.\nPDP candidate Ikenya Joel Danlami won the election, defeating other party candidates.", "Engineering,_Manufacturing": 0.9977907538, "qwen": "Yes"}
{"id": "1689615", "revid": "1604577", "url": "https://en.wikipedia.org/wiki?curid=1689615", "title": "DFMA", "text": "DFMA stands for \"design for manufacture and assembly\". DFMA is the combination of two methodologies; design for manufacture, which means the design for ease of manufacture of the parts that will form a product, and design for assembly, which means the design of the product for ease of assembly deriving creative ideas at the same time. \nUsage.\nDFMA is used as the basis for concurrent engineering studies to provide guidance to the design team in simplifying the product structure, to reduce manufacturing and assembly costs, and to quantify improvements. The practice of applying DFMA is to identify, quantify and eliminate waste or inefficiency in a product design. DFMA is therefore a component of lean manufacturing. DFMA is also used as a benchmarking tool to study competitors’ products, and as a should cost tool to assist in supplier negotiations.\nSoftware.\nDFMA is the name of the integrated set of software products from Boothroyd Dewhurst, Inc. that are used by companies to implement the DFMA methodology. DFMA is a registered trademark of Boothroyd Dewhurst, Inc.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "415209", "revid": "1159759508", "url": "https://en.wikipedia.org/wiki?curid=415209", "title": "List of organisations associated with the Conservative Party (UK)", "text": "This is a list of organisations that are associated with the British Conservative Party. Some are official party organisations, others are organisations made up of party members which are not officially recognised by the party.", "Engineering,_Manufacturing": 0.998989284, "qwen": "Yes"}
{"id": "416779", "revid": "46322105", "url": "https://en.wikipedia.org/wiki?curid=416779", "title": "Scenic design", "text": "Scenic design (also known as scenography, stage design, or set design) is the creation of theatrical scenery. Scenic designers create sets and scenery that aim to support the overall artistic goals of the production. There has been some consideration that scenic design is also production design; however, it is generally considered to be a part of the visual production of a film or television.\nScenic designer.\nThe scenic designer works with the director and other designers to establish an overall visual concept for the production and design the stage environment. They are responsible for developing a complete set of design drawings that include the following:\nMany scenic designers use 3D CAD models to produce these design drawings.\nIn the process of planning, scenic designers often make models. Models are often made before the final drawings that are delivered to the scene shop for construction.\nResponsibility.\nThe scenic designer is responsible for collaborating with the theatre director and other members of the creative team to create an environment for the production. Scenic designers are responsible for creating scale models of the scenery, renderings, paint elevations and scale construction drawings as part of their communication with other production staff. Communicating the details of the scenic environment to the technical director, production manager, charge scenic artist and prop master are among the most important duties of a scenic designer. \nTraining.\nIn Europe and Australia, scenic designers take a more holistic approach to theatrical design and will often be responsible not only for scenic design but costume, lighting and sound and are referred to as theatre designers or scenographers or production designers.\nNotable set designers.\nNotable scenic designers, past and present, include: Adolphe Appia, Boris Aronson, Alexandre Benois, Alison Chitty, Antony McDonald, Barry Kay, Caspar Neher, Cyro Del Nero, Aleksandra Ekster, David Gallo, Edward Gordon Craig, Es Devlin, Ezio Frigerio, Christopher Gibbs, Franco Zeffirelli, George Tsypin, Howard Bay, Inigo Jones, Jean-Pierre Ponnelle, Jo Mielziner, John Lee Beatty, Josef Svoboda, Ken Adam, Léon Bakst, Luciano Damiani, Maria Björnson, Ming Cho Lee, Natalia Goncharova, Nathan Altman, Nicholas Georgiadis, Oliver Smith, Ralph Koltai, Emanuele Luzzati, Neil Patel, Robert Wilson, Russell Patterson, Brian Sidney Bembridge, Santo Loquasto, Sean Kenny, Todd Rosenthal, Robin Wagner, Tony Walton, Louis Daguerre, and Roger Kirk.", "Engineering,_Manufacturing": 0.9936023355, "qwen": "Yes"}
{"id": "838061", "revid": "134766", "url": "https://en.wikipedia.org/wiki?curid=838061", "title": "Broaching (metalworking)", "text": "Broaching is a machining process that uses a toothed tool, called a broach, to remove material. There are two main types of broaching: \"linear\" and \"rotary\". In linear broaching, which is the more common process, the broach is run linearly against a surface of the workpiece to produce the cut. Linear broaches are used in a broaching machine, which is also sometimes shortened to \"broach\". In rotary broaching, the broach is rotated and pressed into the workpiece to cut an axisymmetric shape. A rotary broach is used in a lathe or screw machine. In both processes the cut is performed in one pass of the broach, which makes it very efficient.\nBroaching is used when precision machining is required, especially for odd shapes. Commonly machined surfaces include circular and non-circular holes, splines, keyways, and flat surfaces. Typical workpieces include small to medium-sized castings, forgings, screw machine parts, and stampings. Even though broaches can be expensive, broaching is usually favored over other processes when used for high-quantity production runs.\nBroaches are shaped similar to a saw, except the height of the teeth increases over the length of the tool. Moreover, the broach contains three distinct sections: one for roughing, another for semi-finishing, and the final one for finishing. Broaching is an unusual machining process because it has the feed built into the tool. The profile of the machined surface is always the inverse of the profile of the broach. The rise per tooth (RPT), also known as the \"step\" or feed per tooth, determines the amount of material removed and the size of the chip. The broach can be moved relative to the workpiece or vice versa. Because all of the features are built into the broach, no complex motion or skilled labor is required to use it. A broach is effectively a collection of single-point cutting tools arrayed in sequence, cutting one after the other; its cut is analogous to multiple passes of a shaper.\nHistory.\nThe concept of broaching can be traced back to the early 1850s, with the first applications used for cutting keyways in pulleys and gears. After World War I, broaching was used to rifle gun barrels. In the 1920s and 30s the tolerances were tightened and the cost reduced thanks to advances in form grinding and broaching machines.\nProcess.\nThe process depends on the type of broaching being performed. Surface broaching is very simple as either the workpiece is moved against a stationary surface broach, or the workpiece is held stationary while the broach is moved against it.\nInternal broaching is more involved. The process begins by clamping the workpiece into a special holding fixture, called a \"workholder\", which mounts in the broaching machine. The broaching machine \"elevator\", which is the part of the machine that moves the broach above the workholder, then lowers the broach through the workpiece. Once through, the broaching machine's \"puller\", essentially a hook, grabs the \"pilot\" of the broach. The elevator then releases the top of the follower and the puller pulls the broach through the workpiece completely. The workpiece is then removed from the machine and the broach is raised back up to reengage with the elevator. The broach usually only moves linearly, but sometimes it is also rotated to create a spiral spline or gun-barrel rifling.\nCutting fluids are used for three reasons:\nFortified petroleum cutting fluids are the most common. However, heavy-duty water-soluble cutting fluids are being used because of their superior cooling, cleanliness, and non-flammability.\nUsage.\nBroaching was originally developed for machining internal keyways. However, it was soon discovered that broaching is very useful for machining other surfaces and shapes for high volume workpieces. Because each broach is specialized to cut just one shape, either the broach must be specially designed for the geometry of the workpiece or the workpiece must be designed around a standard broach geometry. A customized broach is usually only viable with high volume workpieces, because the broach can cost US$15,000 to US$30,000 to produce.\nBroaching speeds vary from 20 to 120 surface feet per minute (SFPM). This results in a complete cycle time of 5 to 30 seconds. Most of the time is consumed by the return stroke, broach handling, and workpiece loading and unloading.\nThe only limitations on broaching are that there are no obstructions over the length of the surface to be machined, the geometry to be cut does not have curves in multiple planes, and that the workpiece is strong enough to withstand the forces involved. Specifically for internal broaching a hole must first exist in the workpiece so the broach can enter. Also, there are limits on the size of internal cuts. Common internal holes can range from in diameter but it is possible to achieve a range of . Surface broaches' range is usually , although the feasible range is .\nTolerances are usually ±0.002 in (±0.05 mm), but in precise applications a tolerance of ±0.0005 in (±0.01 mm) can be held. Surface finishes are usually between 16 and 63 microinches (μin), but can range from 8 to 125 μin. There may be small burrs on the exit side of the cut.\nBroaching works best on softer materials, such as brass, bronze, copper alloys, aluminium, graphite, hard rubbers, wood, composites, and plastic. However, it still has a good machinability rating on mild steels and free machining steels. When broaching, the machinability rating is closely related to the hardness of the material. For steels the ideal hardness range is between 16 and 24 Rockwell C (HRC); a hardness greater than HRC 35 will dull the broach quickly. Broaching is more difficult on harder materials, stainless steel and titanium, but is still possible.\nTypes.\nBroaches can be categorized by many means:\nIf the broach is large enough the costs can be reduced by using a \"built-up\" or \"modular\" construction. This involves producing the broach in pieces and assembling it. If any portion wears out only that section has to be replaced, instead of the entire broach.\nMost broaches are made from high speed steel (HSS) or an alloy steel; titanium nitride (TiN) coatings are common on HSS to prolong life. Except when broaching cast iron, tungsten carbide is rarely used as a tooth material because the cutting edge will crack on the first pass.\nSurface broaches.\nThe \"slab broach\" is the simplest surface broach. It is a general purpose tool for cutting flat surfaces.\n\"Slot broaches\" (G & H) are for cutting slots of various dimensions at high production rates. Slot broaching is much quicker than milling when more than one slot needs to be machined, because multiple broaches can be run through the part at the same time on the same broaching machine.\n\"Contour broaches\" are designed to cut concave, convex, cam, contoured, and irregular shaped surfaces.\n\"Pot broaches\" are cut the inverse of an internal broach; they cut the outside diameter of a cylindrical workpiece. They are named after the pot looking fixture in which the broaches are mounted; the fixture is often referred to as a \"pot\". The pot is designed to hold multiple broaching tools concentrically over its entire length. The broach is held stationary while the workpiece is pushed or pulled through it. This has replaced hobbing for some involute gears and cutting external splines and slots.\n\"Straddle broaches\" use two slab broaches to cut parallel surfaces on opposite sides of a workpiece in one pass. This type of broaching holds closer tolerances than if the two cuts were done independently. It is named after the fact that the broaches \"straddle\" the workpiece on multiple sides.\nInternal broaches.\n\"Solid\" broaches are the most common type; they are made from one solid piece of material. For broaches that wear out quickly \"shell\" broaches are used; these broaches are similar to a solid broach, except there is a hole through the center where it mounts on an arbor. Shell broaches cost more initially, but save the cost overall if the broach must be replaced often because the pilots are on the mandrel and do not have to be reproduced with each replacement.\n\"Modular\" broaches are commonly used for large internal broaching applications. They are similar to shell broaches in that they are a multi-piece construction. This design is used because it is cheaper to build and resharpen and is more flexible than a solid design.\nA common type of internal broach is the \"keyway\" broach (C & D). It uses a special fixture called a \"horn\" to support the broach and properly locate the part with relation to the broach.\nA \"concentricity broach\" is a special type of spline cutting broach which cuts both the minor diameter and the spline form to ensure precise concentricity.\nThe \"cut-and-recut broach\" is used to cut thin-walled workpieces. Thin-walled workpieces have a tendency to expand during cutting and then shrink afterward. This broach overcomes that problem by first broaching with the standard roughing teeth, followed by a \"breathing\" section, which serves as a pilot as the workpiece shrinks. The teeth after the \"breathing\" section then include roughing, semi-finishing, and finishing teeth.\nDesign.\nFor defining the geometry of a broach an internal type is shown below. Note that the geometries of other broaches are similar.\nwhere:\nThe most important characteristic of a broach is the rise per tooth (RPT), which is how much material is removed by each tooth. The RPT varies for each section of the broach, which are the roughing section (\"t\"r), semi-finishing section (\"t\"s), and finishing section (\"t\"f). The roughing teeth remove most of the material so the number of roughing teeth required dictates how long the broach is. The semi-finishing teeth provide surface finish and the finishing teeth provide the final finishing. The finishing section's RPT (tf) is usually zero so that as the first finishing teeth wear the later ones continue the sizing function. For free-machining steels the RPT ranges from . For surface broaching the RPT is usually between and for diameter broaching is usually between . The exact value depends on many factors. If the cut is too big it will impart too much stress into the teeth and the workpiece; if the cut is too small the teeth rub instead of cutting. One way to increase the RPT while keeping the stresses down is with \"chip breakers\". They are notches in the teeth designed to break the chip and decrease the overall amount of material being removed by any given tooth (see the drawing above). For broaching to be effective, the workpiece should have more material than the final dimension of the cut.\nThe \"hook\" (\"α\") angle is a parameter of the material being cut. For steel, it is between 15 and 20° and for cast iron it is between 6 and 8°. The \"back-off\" (\"γ\") provides clearance for the teeth so that they don't rub on the workpiece; it is usually between 1 and 3°.\nWhen radially broaching workpieces that require a deep cut per tooth, such as forgings or castings, a \"rotor-cut\" or \"jump-cut\" design can be used; these broaches are also known as \"free egress\" or \"nibbling\" broaches. In this design the RPT is designated to two or three rows of teeth. For the broach to work the first tooth of that cluster has a wide notch, or undercut, and then the next tooth has a smaller notch (in a three tooth design) and the final tooth has no notch. This allows for a deep cut while keeping stresses, forces, and power requirements low.\nThere are two different options for achieving the same goal when broaching a flat surface. The first is similar to the rotor-cut design, which is known as a \"double-cut\" design. Here four teeth in a row have the same RPT, but each progressive tooth takes only a portion of the cut due to notches in the teeth (see the image gallery below). The other option is known as a \"progressive\" broach, which completely machines the center of the workpiece and then the rest of the broach machines outward from there. All of these designs require a broach that is longer than if a standard design were used.\nFor some circular broaches, \"burnishing teeth\" are provided instead of finishing teeth. They are not really teeth, as they are just rounded discs that are oversized. This results in burnishing the hole to the proper size. This is primarily used on non-ferrous and cast iron workpieces.\nThe pitch defines the tooth construction, strength, and number of teeth in contact with the workpiece. The pitch is usually calculated from workpiece length, so that the broach can be designed to have at least two teeth in contact with the workpiece at any time; the pitch remains constant for all teeth of the broach. One way to calculate the pitch is:\nBroaching machines.\nBroaching machines are relatively simple as they only have to move the broach in a linear motion at a predetermined speed and provide a means for handling the broach automatically. Most machines are hydraulic, but a few specialty machines are mechanically driven. The machines are distinguished by whether their motion is horizontal or vertical. The choice of machine is primarily dictated by the stroke required. Vertical broaching machines rarely have a stroke longer than .\nVertical broaching machines can be designed for push broaching, pull-down broaching, pull-up broaching, or surface broaching. Push broaching machines are similar to an arbor press with a guided ram; typical capacities are 5 to 50 tons. The two ram pull-down machine is the most common type of broaching machine. This style machine has the rams under the table. Pull-up machines have the ram above the table; they usually have more than one ram. Most surface broaching is done on a vertical machine.\nHorizontal broaching machines are designed for pull broaching, surface broaching, continuous broaching, and rotary broaching. Pull style machines are basically vertical machines laid on the side with a longer stroke. Surface style machines hold the broach stationary while the workpieces are clamped into fixtures that are mounted on a conveyor system. Continuous style machines are similar to the surface style machines except adapted for internal broaching.\nHorizontal machines used to be much more common than vertical machines; however, today they represent just 10% of all broaching machines purchased. Vertical machines are more popular because they take up less space.\nBroaching is often impossible without the specific broaching or keyway machines unless you have a system that can be used in conjunction with a modern machining centre or driven tooling lathe; these extra bits of equipment open up the possibility of producing keyways, splines and Torx through one-hit machining.\nRotary broaching.\nA somewhat different design of cutting tool that can achieve the irregular hole or outer profile of a broach is called a \"rotary broach\" or \"wobble broach\". One of the biggest advantages to this type of broaching is that it does not require a broaching machine, but instead is used on lathes, milling machines, screw machines or Swiss lathes.\nRotary broaching requires two tooling components: a tool holder and a broach. The leading (cutting) edge of the broach has a contour matching the desired final shape. The broach is mounted in a special tool holder that allows it to freely rotate. The tool holder is special because it holds the tool so that its axis of rotation is inclined slightly to the axis of rotation of the work. A typical value for this misalignment is 1°. This angle is what produces a rotating edge for the broach to cut the workpiece. Either the workpiece or the tool holder is rotated. If the tool holder is rotated, the misalignment causes the broach to appear as though it is \"wobbling\", which is the origin of the term \"wobble broach\".\nFor internal broaching the sides of the broach are drafted inward so it becomes thinner; for external broaching the sides are drafted outward, to make the pocket bigger. This draft keeps the broach from jamming; the draft must be larger than the angle of misalignment. If the work piece rotates, the broach is pressed against it, is driven by it, and rotates synchronously with it. If the tool holder rotates, the broach is pressed against the workpiece, but is driven by the tool holder.\nIdeally the tool advances at the same rate that it cuts. The ideal rate of cut is defined as:\nIf it advances much faster, then the tool becomes choked; conversely, if it advances much slower, then an interrupted or zig-zag cut occurs. In practice the rate of cut is slightly less than the ideal rate so that the load is released on the non-cutting edge of the tool.\nThere is some spiraling of the tool as it cuts, so the form at the bottom of the workpiece may be rotated with respect to the form at the top of the hole or profile. Spiraling may be undesirable because it binds the body of the tool and prevents it from cutting sharply. One solution to this is to reverse the rotation in mid cut, causing the tool to spiral in the opposite direction. If reversing the machine is not practical, then interrupting the cut is another possible solution.\nIn general, a rotary broach will not cut as accurately as a push or pull broach. However, the ability to use this type of cutting tool on common machine tools is highly advantageous. In addition, push or pull broaches cannot be used in a blind hole, while a rotary broach can, as long as there is sufficient space for chips at the bottom of the hole.", "Engineering,_Manufacturing": 0.999994874, "qwen": "Yes"}
{"id": "838247", "revid": "1126265", "url": "https://en.wikipedia.org/wiki?curid=838247", "title": "Harbin Aircraft Industry Group", "text": "Harbin Aircraft Industry (Group) Co., Ltd. (HAIG), often shortened to Hafei , is an aircraft manufacturing company headquartered in Pingfang District, Harbin, Heilongjiang province, China. It was previously called Harbin Aircraft Manufacturing Corporation (HAMC) in English.\nThe company was founded in 1952 to manufacture planes for domestic sales, but today it supplies various components for foreign aerospace companies. It is a subsidiary of the Aviation Industry Corporation of China (AVIC).\nA former subsidiary of Harbin Aircraft Manufacturing Corporation — Hafei Motor, is one of the major automobile manufactures in China.\nHistory.\nThe 1st factory opened in 1952 to repair aircraft and situated on the former site of the Manchuria Airplane Manufacturing Company (Manshū/Mansyuu) factory. In 1958, it began producing licensed copies of Soviet aircraft. It produced the Z-5, the Mil Mi-4 helicopter, and the H-5 light bomber — a copy of the Ilyushin Il-28.\nIt then produced the Harbin Y-11 a light twin-engined utility aircraft — an aircraft of its own design and not a licensed copy. The Harbin Y-12 which followed, while similar to the Y-11, was a largely new aircraft.\nThe most recent and important product is the Z-20 utility helicopter designed and built for the Chinese military.\nMajor products.\nHelicopters\nBombers\nPatrol/Utility Aircraft\nTransports\nUnmanned Aerial vehicles\nFormer Production", "Engineering,_Manufacturing": 0.9999520779, "qwen": "Yes"}
{"id": "841755", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=841755", "title": "Selective laser sintering", "text": "Selective laser sintering (SLS) is an additive manufacturing (AM) technique that uses a laser as the power and heat source to sinter powdered material (typically nylon or polyamide), aiming the laser automatically at points in space defined by a 3D model, binding the material together to create a solid structure. It is similar to selective laser melting; the two are instantiations of the same concept but differ in technical details. SLS (as well as the other mentioned AM techniques) is a relatively new technology that so far has mainly been used for rapid prototyping and for low-volume production of component parts. Production roles are expanding as the commercialization of AM technology improves.\nHistory.\nSelective laser sintering (SLS) was developed and patented by Dr. Carl Deckard and academic adviser, Dr. Joe Beaman at the University of Texas at Austin in the mid-1980s, under sponsorship of DARPA. Deckard and Beaman were involved in the resulting start up company DTM, established to design and build the SLS machines. In 2001, 3D Systems, the biggest competitor to DTM and SLS technology, acquired DTM. The most recent patent regarding Deckard's SLS technology was issued January 28, 1997 and expired January 28, 2014.\nA similar process was patented without being commercialized by R. F. Housholder in 1979.\nAs SLS requires the use of high-powered lasers it is often too expensive, not to mention possibly too dangerous, to use in the home. The associated expense and potential danger of SLS printing due to lack of commercially available laser systems with Class-1 safety enclosures means that the home market for SLS printing is not as large as the market for other additive manufacturing technologies, such as Fused Deposition Modeling (FDM).\nTechnology.\nAn additive manufacturing layer technology, SLS involves the use of a high power laser (for example, a carbon dioxide laser) to fuse small particles of plastic, metal, ceramic, or glass powders into a mass that has a desired three-dimensional shape. The laser selectively fuses powdered material by scanning cross-sections generated from a 3-D digital description of the part (for example from a CAD file or scan data) on the surface of a powder bed. After each cross-section is scanned, the powder bed is lowered by one layer thickness, a new layer of material is applied on top, and the process is repeated until the part is completed.\nBecause finished part density depends on peak laser power, rather than laser duration, a SLS machine typically uses a pulsed laser. The SLS machine preheats the bulk powder material in the powder bed somewhat below its melting point, to make it easier for the laser to raise the temperature of the selected regions the rest of the way to the melting point.\nIn contrast with SLA and FDM, which most often require special support structures to fabricate overhanging designs, SLS does not need a separate feeder for support material because the part being constructed is surrounded by unsintered powder at all times. This allows for the construction of previously impossible geometries. Also, since the machine's chamber is always filled with powder material the fabrication of multiple parts has a far lower impact on the overall difficulty and price of the design because through a technique known as 'Nesting', where multiple parts can be positioned to fit within the boundaries of the machine. One design aspect which should be observed however is that with SLS it is 'impossible' to fabricate a hollow but fully enclosed element. This is because the unsintered powder within the element could not be drained.\nSince patents have started to expire, affordable home printers have become possible, but the heating process is still an obstacle, with a power consumption of up to 5 kW and temperatures having to be controlled within 2 °C for the three stages of preheating, melting and storing before removal. \nMaterials.\nThe quality of printed structures depends on the various factors include powder properties such as particle size and shape, density, roughness, and porosity. Furthermore, the particle distribution and their thermal properties affect a lot on the flowability of the powder.\nCommercially-available materials used in SLS come in powder form and include, but are not limited to, polymers such as polyamides (PA), polystyrenes (PS), thermoplastic elastomers (TPE), and polyaryletherketones (PAEK). Polyamides are the most commonly used SLS materials due to their ideal sintering behavior as a semi-crystalline thermoplastic, resulting in parts with desirable mechanical properties. Polycarbonate (PC) is a material of high interest for SLS due to its high toughness, thermal stability, and flame resistance; however, such amorphous polymers processed by SLS tend to result in parts with diminished mechanical properties, dimensional accuracy and thus are limited to applications where these are of low importance. Metal materials are not commonly used in SLS since the development of selective laser melting.\nPowder Production.\nPowder particles are typically produced by cryogenic grinding in a ball mill at temperatures well below the glass transition temperature of the material, which can be reached by running the grinding process with added cryogenic materials such as dry ice (dry grinding), or mixtures of liquid nitrogen and organic solvents (wet grinding). The process can result in spherical or irregular shaped particles as low as five microns in diameter. Powder particle size distributions are typically gaussian and range from 15 to 100 microns in diameter, although this can be customized to suit different layer thicknesses in the SLS process. Chemical binder coatings can be applied to the powder surfaces post-process; these coatings aid in the sintering process and are especially helpful to form composite material parts such as with alumina particles coated with thermoset epoxy resin.\nSintering mechanisms.\nSintering in SLS primarily occurs in the liquid state when the powder particles forms a micro-melt layer at the surface, resulting in a reduction in viscosity and the formation of a concave radial bridge between particles, known as necking, due to the material's response to lower its surface energy. In the case of coated powders, the purpose of the laser is to melt the surface coating which will act as a binder. Solid state sintering is also a contributing factor, albeit with a much reduced influence, and occurs at temperatures below the melting temperature of the material. The principal driving force behind the process is again the material's response to lower its free energy state resulting in diffusion of molecules across particles.\nApplications.\nSLS technology is in wide use at many industries around the world due to its ability to easily make complex geometries with little to no added manufacturing effort. Its most common application is in prototype parts early in the design cycle such as for investment casting patterns, automotive hardware, and wind tunnel models. SLS is also increasingly being used in limited-run manufacturing to produce end-use parts for aerospace, military, medical, pharmaceutical, and electronics hardware. On a shop floor, SLS can be used for rapid manufacturing of tooling, jigs, and fixtures. Because the process requires the use of a laser and other expensive, bulky equipment, it is not suited for personal or residential use; however, it has found applications in art [EOS artist citation with images].", "Engineering,_Manufacturing": 0.9999667406, "qwen": "Yes"}
{"id": "30765735", "revid": "2278355", "url": "https://en.wikipedia.org/wiki?curid=30765735", "title": "Xeros Washing Machine", "text": "The Xeros Washing Machine is a new kind of clothes washing technology that cleans laundry using primary nylon polymer beads and very little water. The machine releases nylon polymer beads into a main compartment where laundry is washed. These beads are small and super absorbent which allows them to go through clothing to absorb dirt and stains. This technology is invented by University of Leeds professor Stephen Burkinshaw, who currently has partnership with Xeros Ltd. in perfecting this technology.\nTechnology.\nThe Washing Machine cleans using nylon polymer beads and one-tenth of the water used by traditional washing machine. Instead of cleaning clothes with water, the machine uses reusable nylon for its cleaning process. Nylon polymer beads are more absorbent than water, which allows them to absorb stains right into their core.\nThe Washing Machine creates a humid condition in the clothes compartment. This process causes the polymer chains in the nylon to separate slightly, making the beads absorbent. The beads then absorb and lock the stains in their core.\nProcess.\nFirst, laundry is inserted into the compartment of the machine. The machine then releases nylon polymer beads and water containing detergent onto the garments. The washing cycle begins and the beads begin to absorb stains. After the cycle ends, the nylon polymer beads are then separated by a drum in drum separation process that is projected to remove 99.95% of the beads; any remaining beads can either be shaken off or removed with the use of a vacuum wand (included with the purchase of the machine).\nInventor/Developer.\nThe washing machine’s system is based on Professor Stephen Burkinshaw’s research. Burkinshaw spent his time at the University of Leeds focusing on the structure of nylon polymer beads. He discovered that nylon is the best material for absorbing tiny particles, and together with his team of researchers came up with the concept of using nylon beads to remove stains from clothes.\nProfessor Stephen Burkinshaw and his team of researchers are currently in partnership with Xeros Ltd. and are planning to commercially produce waterless washing machines by the end of 2011.\nEnvironmental and Energy Costs.\nAccording to Xeros Ltd., its technology uses 90% less water than the conventional washing machine. While a front-loading washer uses about 20–25 gallons of water, the Xeros Washing Machine is estimated to use as little as one gallon of water.\nThe machine is also projected to save consumers up to 30% for operating costs in electricity and water.\nEven though this device saves on operating costs, compared with other washing machines, the initial retail price of the machine is still unknown and could outweigh the saved operating cost over the product's lifetime.\nRanking.\nThe Xeros Washing Machine was ranked one of The 50 Best Inventions of 2010 by www.time.com.", "Engineering,_Manufacturing": 0.9981225729, "qwen": "Yes"}
{"id": "30792206", "revid": "6209078", "url": "https://en.wikipedia.org/wiki?curid=30792206", "title": "Fokker Technologies", "text": "Fokker Technologies is a Dutch aerospace company owned by British aerospace supplier GKN. The company has production companies which design, develop and produce structures, landing gear and electrical systems for the aerospace and defense industry. Additional to the production capabilities, it also supplies integrated maintenance services to aircraft owners and operators.\nOperations.\nFokker Technologies designs, develops and produces advanced structures and electrical systems for the aerospace and defense industry and supplies integrated maintenance services and products to aircraft owners and operators.\nThe company consists of four business units:\nHistory.\nAfter the bankruptcy of the former aircraft manufacturer Fokker in 1996, Stork B.V. acquired the Fokker companies specialized in the building of aircraft components and aircraft maintenance services which were named as Stork Aerospace. The group has had many names until in 2010, the Fokker name was reintroduced.\nIn July 2015, the British aerospace supplier GKN announced that it intention to acquire Fokker Technologies from Arle Capital, at the value of €706 million. Fokker was acquired in the same year by GKN.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "62657290", "revid": "1167465434", "url": "https://en.wikipedia.org/wiki?curid=62657290", "title": "Skateboard (automotive platform)", "text": "A skateboard is a type of configuration for automotive chassis, used for automotive platforms of battery electric vehicles. The skateboard chassis includes a base structure or a platform, which houses the batteries, electric motors and other electronic components fundamental to an electric vehicle.\nA skateboard chassis cuts down the cost and complexity of manufacturing and production of electric vehicles, as it is a self-contained platform, with all the necessary driving and electronic components integrated into it, and which can be mounted with a variety of bodies after scaling them into various sizes. The skateboard allows an automaker to design and manufacture vehicles in several vehicle categories and body segments without engineering each one independently.", "Engineering,_Manufacturing": 0.9999706745, "qwen": "Yes"}
{"id": "62671320", "revid": "17521300", "url": "https://en.wikipedia.org/wiki?curid=62671320", "title": "Prusa Mini", "text": "The Prusa Mini, sometimes stylized as the Original Prusa MINI, is an open-source fused deposition modeling 3D printer that is manufactured by the Czech company Prusa Research. The printer is the lowest cost machine produced by Prusa Research and is designed as a first printer or as part of a 'print farm'.\nSpecifications.\nMini.\nThe Prusa Mini was officially launched in October 2019. The printer is available either assembled or as a kit. The build volume is 180 x 180 x 180 mm, and the print is performed on a spring steel sheet which meant to be easy to remove. Minimum layer resolution is 50 micrometers, and the maximum print speed is 200 millimeters per second. The printer has an LCD color display (non-touch), is able to print via USB drives. It has a custom 32-bit mainboard and a built-in online firmware updater. The printer has sensorless homing using Trinamic 2209 drivers and has a custom hot end which supports E3D nozzles.\nIt has several safety features including three thermistors to detect thermal runaway.\nThe printer is the first open source hardware product to require a user wishing to use unsigned firmware to physically break off a piece of the PCB, voiding the printer's warranty, before it can be flashed onto the board. This made sure Prusa wasn't liable for damage caused by printers instructed to behave in an unendorsed manner by custom firmware (such as disabling thermal runaway protections or other safety features).\nMini+.\nIn November 2020, the Prusa Mini was replaced by the Mini+, which had a few small updates meant to ease assembly and maintenance. One of the changes was a new mesh bed levelling sensor called \"SuperPINDA\" which replaced the previous \"MINDA\" sensor, and it is claimed by the manufacturer that this should result in a more consistent calibration of the first print layer in particular. The Mini+ the filament sensor, is an optional extra.", "Engineering,_Manufacturing": 1.0000023842, "qwen": "Yes"}
{"id": "11221995", "revid": "1119675693", "url": "https://en.wikipedia.org/wiki?curid=11221995", "title": "List of British Rail power classifications", "text": "The British Transport Commission, later British Railways, used engine power output to categorise its requirements for the new main line diesel locomotive fleet following the 1955 modernisation plan. The locomotives built and put into service are listed below classified with the TOPS class numbers that were introduced in the early 1970s.\nType 1.\nLocomotives classed as Type 1 were of 1,000 bhp or below.\nType 2.\nLocomotives classed as Type 2 produced between 1,001 bhp and 1,499 bhp.\nType 3.\nLocomotives classed as Type 3 produced between 1,500 bhp and 1,999 bhp.\nType 4.\nLocomotives classed as Type 4 produced between 2,000 bhp and 2,999 bhp.\nType 5.\nLocomotives classed as Type 5 produced 3,000 bhp or more.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "11235056", "revid": "4071608", "url": "https://en.wikipedia.org/wiki?curid=11235056", "title": "Feature recognition", "text": "The term \"feature\" implies different meanings in different engineering disciplines. This has resulted in many ambiguous definitions for feature. A feature, in computer-aided design (CAD), usually refers to a region of a part with some interesting geometric or topological properties. These are more precisely called form features. Form features contain both shape information and parametric information of a region of interest. They are now ubiquitous in most current CAD software, where they are used as the primary means of creating 3D geometric models. Examples of form features are extruded boss, loft, etc. Form feature is not the only type of feature that is discussed in CAD literature. Sometimes a part's functional or manufacturing features of the subject of attention. Although it is quite possible to see form features and manufacturing features are called by the same name, they are not exactly the same concepts. For example, one may either use the name \"pocket\" to refer to a swept cut on the boundary of a part model, or to refer to a trace left on the part boundary by a specific machining operation. The former is exclusively concerned with a geometric shape whereas the latter is concerned with both the geometric shape and a manufacturing operation, needing more parameters in its definition. As such, a manufacturing feature can be minimally defined as a form feature (if it has a form that can uniquely represent it), but not necessarily vice versa (forms can be interpreted differently in different manufacturing domains). Machining features are an important subset of manufacturing features. A machining feature can be regarded as the volume swept by a \"cutting\" tool, which is always a negative (subtracted) volume. Finally, there is also the concept of assembly feature, which encodes the assembly method between connected components.\nFeature data in CAD can be specified either as a collection of surfaces or as volumes. Surface features can be used to describe manufacturing tolerances or locating surfaces in assembly design. Volumetric features on the other hand, can be used in tool path generation, etc. Manufacturing information (particularly in machining) is better portrayed by using volumetric features.\nThe first published work on features was for the original boundary representation modelling system, BUILD, and was performed by Lyc Kyprianou. Soon other work followed based on different solid representations. Overviews on the work on features can be found in Shah et al.; Subrahmanyam and Wozny; Salomons et al.\nTechnology.\nWork on features (generally called feature technology) can be divided into two rough categories: Design-by-features and Feature recognition. In design-by-features, also known as feature-based design (FBD), feature structures are introduced directly into a model using particular operations or by sewing in shapes. On the other hand, the goal of feature recognition (FR) is to algorithmically extract higher level entities (e.g. manufacturing features) from lower level elements (e.g. surfaces, edges, etc.) of a CAD model.\nForm feature generation model.\nCompleteness of feature set is very subjective, domain dependence eludes a formal definition. Feature generation model proposed by Nalluri and Gurumoorthy attempts to define the completeness of a feature set. They define domain independent form feature as a set of faces with distinct topological and geometric characteristics. They have modelled creation of a form feature as addition/subtraction of feature-solid (exact minimum volume required) to/from based-solid. They define feature \"Type\" based on the local topology of participating base-solid faces and \"shape\" based on shape of the feature-solid. Based on these definitions, they have enumerated and classified form features. For example, they have enumerated 94 sweep form feature types with possibility of each feature type having unlimited number of shapes. They provided proof those 94 types are complete for sweep feature-solid. They have modeled the feature extraction as a reverse process of their feature generation model. They have developed a feature recognition algorithm based on the concept of computing dynamic topological status of faces. They also defined a framework for mapping these domain independent features to a specific domain of interest.\nDesign by features.\nBy using features to build up shape models, the design process is made more efficient, because the shape of features can be pre-defined. Features in FBD can be directly associated to manufacturing information so that these informations can be retrieved in downstream applications. In this way, an overall CAD/CAM system can be fully automated, however, the idea of using manufacturing features to design a part has its own shortcomings: The features used to design the part do not necessarily represent the best way to manufacture it. It is, therefore, the designer's responsibility to evaluate all methods that can produce the part. Furthermore, manufacturing features are not the most natural way of designing a part.\nFeature recognition.\nThe method proposed by Kyprianou was aimed to encode parts for group technology (GT). The purpose of GT is to systematically classify objects based on their manufacturing method. Kyprianou's work involved classifying faces into primary and secondary groups and then identifying features according to patterns of these primary or secondary faces. A primary face is one with multiple boundaries (also called \"hole-loops\") or mixed concave and convex boundaries. A concave boundary is a set of concave edges, where the solid angle over the edge is more than 180. Secondary faces are all other faces. Kyprianou's work was continued and extended by Jared et al. to cover a number of important special cases where features interacted.\nAutomatic Feature Recognition (AFR) is regarded as an ideal solution to automate design and manufacturing processes. Successful automation of CAD and CAM systems is a vital connection in building Computer Integrated Manufacturing (CIM) systems. This is the part of the FR research that has attracted much of the attention. Another important application of AFR is for manufacturability evaluation. The AFR system should be able to interpret the design differently based on alternative features and feed back the manufacturability and cost of those interpretations to the designer.\nThere is a big stockpile of different AFR techniques that has been proposed for CAD/CAM integration and process planning. Han et al. provides a critical and detailed analysis of some of the existing approaches. The most common methods according to Han et al. range from graph-based algorithms to hint-based and volumetric decomposition techniques. In the graph-based feature recognition, a graph showing the topology of the part (connection of faces) is created. The graph is often attributed, for example the edges are marked as concave or convex. This graph is then analyzed to extract subsets of nodes and arcs that match with any predefined template. This is done by a variety of techniques, including graph iso-morphism algorithms.\nGraph based approaches have been criticized for several shortcomings. They fail to account for manufacturability of the recognized features due to their strong reliance on topological patterns rather than geometry. The intersection of features causes an explosion in the number of possible feature patterns that spoils any attempt to formulate feature patterns. To address these difficulties, Vandenbrande and Requicha. proposed to search for \"minimal indispensable portion of a feature's boundary\", called hints, rather than complete feature patterns. For example, presence of two opposing planar faces is a hint for potential existence of a slot feature. Hints are not necessarily restricted to the part geometry. They can be extracted form tolerances and design attributes as well. For example, \"a thread attribute may be taken as a hole hint\". This approach has been more successful in recognizing intersecting features. However, the efficiency of the approach has been argued, as there could be a huge number of traces that won't lead to valid features. Some authors have been in favor of using a hybrid of graph based and hint based FR to improve the efficiency of hint-based reasoning. In the hybrid approach, graph-based reasoning is used to find out those regions of the part that certainly lead to valid features when used by the hint based reasoner. Other existing FR approaches are volumetric decomposition, Artificial Neural Networks, and expert systems Babic et al. briefly introduces many of them.\nHowever, building feature recognition systems that function effectively on real industrial products has been elusive. A real product with hundreds of faces and end edges brings almost all the above approaches to a halt due to computational complexity. Furthermore, the features studied in these approaches are usually over simplified. The bulk of the feature recognition literature normally deals with 2.5D features (those made by sweeping a 2D profile along a linear axis). Graph representations, hint definitions or volume decompositions are much more difficult to define for 3D and free form features. The work done by Sundararajan is focused on free form surfaces, but again it is limited in application. Oversimplification is also evident even in the course of 2.5D features. For example, feature recognition algorithms usually assume sharp concave edges in the feature geometry. However, such edges are barely used in real design of mechanical components due to manufacturing constrains. Some of these issues such as the presence of filleted edges and free form surfaces in the model have been studied by Rahmani and Arezoo.\nCommercial feature recognition systems.\nFew commercial feature recognition systems are also available. Though feature recognition technology can be applied for various applications, commercial software have effectively adopted feature recognition technology for recreating the feature tree from imported models so that even the imported models can be edited as if it were a native solid model. Major 3D CAD modelers have Feature Recognition to convert imported 3-D models into native feature based models. CAM software and design for manufacturing software are also built using this feature recognition technology. Few CAD/CAM software have used commercially available third-party feature recognition library, which recognizes various features from 3-D B-Rep models. Separate libraries are available for Design, Manufacturing and Sheet metal applications. Design feature recognition library can identify features such as holes of various types, split holes, hole-chains, fillets, chamfers, cut extrudes, boss extrudes, drafted extrudes, revolved cuts, revolved bosses, ribs, drafts, lofts and sweeps are identified. Manufacturing feature recognition library provides recognition of manufacturing features such as simple holes, tapered holes, counter-bore holes, counter-sunk holes, counter-drilled holes, hole-chains, hole patterns such as linear, rectangular and circular patterns, fillets, chamfers, blind pockets, through pockets, drafted pockets, filleted and chamfered pockets, simple slots, drafted slots, filleted and chamfered slots, islands in pockets and slots, machinable volumes, machinable slabs, multiple intersecting features, axi-symmetric features such as external turned profiles, internal turned profiles, turned grooves such as vee and dovetail grooves, and mill-turn features such as slots and pocket in turned profiles. Sheet metal feature recognition library extracts features from a sheet metal perspective. Various features identified through this library include walls, bends, holes, cutouts, flanged holes, flanged cutouts, notches, open hems, closed hems, teardrop hems, rolled hems (curls), jog flanges, edge flanges, contour flanges, stamps such as louver, lance, bridge, dimple, beads, embosses and ribs. Though such commercial systems can identify a variety of features listed above, further research can be driven to identify feature types that are not identified by such commercial systems. Manufacturing features such as 3-axis and 5-axis feature recognition are generally not available in such commercial systems.", "Engineering,_Manufacturing": 0.9999946356, "qwen": "Yes"}
{"id": "11237703", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=11237703", "title": "Sigg", "text": "Sigg Switzerland AG is a Swiss manufacturing company with its headquarters in Frauenfeld. Sigg bottles are bottles designed and manufactured in Switzerland from aluminum and polypropylene or in China from stainless steel and glass. The company is famous because of the iconic shape its classic bottle and numerous designs which have led to its addition to the permanent design collection of the New York Museum of Modern Art.\nHistory.\nThe company was founded in Biel in 1908 by Ferdinand Sigg und Xavier\nKüng under the name Küng, Sigg & Cie. and produced kitchenware, bottles and\nelectrical appliances from aluminum. In 1916 the company moved to Frauenfeld and changed the name to\nSIGG Aluminiumfabrik. Since 1998, the company has concentrated on the manufacture of bottles. According to market research, the company name is known by 70 percent of people in German-speaking countries.\nThrough the 1980s Sigg manufactured impact-extruded aluminum bottles for stove fuel storage and transport, popular with mountaineers, hikers and campers. The fuel bottles superficially resemble the water bottles, but lack the special linings of the latter. Now the company doesn't manufacture fuel bottles anymore.\nOn February 5, 2016, the Chinese company Haers Vacuum Containers announced it acquired the bottle manufacturer for 16.1 million Swiss franc ($16.02 million).\nInterchangeability.\nAll Sigg bottles use the same diameter head and thread system, which results in interchangeability of bottles and caps. Different cap styles exist, such as a normal screw on cap with loop, caps with glow-in-the-dark markers, sports-bottle caps and caps with added protection from dust.\nAluminum bottles.\nThe aluminum bottles are made by an extruding press which forms an aluminum puck into a cylinder in a single movement after which it is pressed into one of several possible bottle sizes. A separate threading ring is inserted and secured. Once the bottle has been formed, it is cleaned and the interior is sprayed with a food-compatible stove enamel which is heated while the outside is coated and heat bonded with powder paint.\nAluminum bottles are resistant to shocks and disformations, are lightweight, and protect the contents from light. The interior coating is flexible and is unlikely to break or crack during deformations. Sigg bottles have been determined by Backpacker magazine to be the \"world's toughest water bottle\" when they fired golf balls at the water bottles with a 100-pound cannon.\nThe bottle with its internal liner and secure cap allow for carbonated beverages to be transported secure and freshly. All Sigg bottles manufactured after August 2008 use the \"EcoCare\" liner, which Sigg states is 'made from BPA-free and phthalate-free ingredients'.\nThe disadvantage of thin aluminum is that it does not offer much insulation, which means that condensation can build on the outside of the bottle when cold drinks are transported, and hot drinks will result in a bottle which cannot be comfortably touched. Sigg sells insulating sleeves that protect the bottle from dents, help insulate the beverages inside them and eliminate the condensation issue. The limited size of the opening also makes it difficult to fill or clean the bottle or to use it for purposes other than drinking, though Sigg now makes wide-mouth bottles, and adapters that allow the use of the standard-size caps. Aluminum bottles are also more prone to dents than stainless steel bottles. Another disadvantage is that the bottles are unsuitable for freezing its contents, as freezing liquids expand in volume and cause the bottle to crack. Therefore, it is advisable not to keep fluids in the container during extended periods below freezing temperatures.\nStainless steel bottles.\nIn 2013 SIGG introduced a new material into its collection, stainless steel. With the Hot & Cold line made of stainless steel SIGG offers a solution for insulated bottles. These bottles have a double wall vacuum insulation which allows them to keep temperatures, cold or hot, during several hours. One advantage of these bottles is that they do not need an inner liner to protect the liquids and they are more resistant against dents and scratches than the aluminum bottles.\nPolypropylene bottles.\nSince April 2014 SIGG started manufacturing bottles made of high-grade 100% recyclable polypropylene, a safe, durable and eco-friendly plastic. As part of the philosophy of the company means to keep the swissness of its products, the SIGG VIVA bottles are produced in Switzerland. SIGG ensures that these bottles are free of BPA and they are produced with the same ecological standards of the aluminum bottles. These sport orientated bottles have the advantage that they are transparent allowing to see the inside and they are very resistant against dent and scratches.\nGlass bottle.\nIn 2015 SIGG the Swiss company enlarged its portfolio of product materials with presented a new bottle made of glass. The bottle consists of two walls of heat-resistant borosilicate glass, a WMB (wide mouth bottle) opening to allow for the addition of ice cubes, and two removable silicone elements: a grip around the body of the bottle and a base stand with shock-absorbing strips. These elements protect the fingers and prevent the bottle from breaking by being knocked or set down too heavily. The two separate glass walls provide optimal insulation, so cold drinks stay cool (for up to two hours) and hot drinks stay pleasantly warm (for up to one hour). The bottle can be comfortably handled even when it contains hot drinks and the outer wall does not build up condensation when it contains cold ones. The liquid only comes into contact with glass and stainless steel so its flavor remains unaffected. All the materials used for the bottle are BPA and BPS free.\nDesign.\nEach year, new designs of the Sigg bottle are added to the collection while others are no longer produced. The design of Sigg bottle has led to its addition to the permanent design collection of the New York Museum of Modern Art. The classic bottle is of a single colour (most often red) whilst more modern bottles can have designs on them and are available in both glossy or matte finishes.", "Engineering,_Manufacturing": 0.9948639274, "qwen": "Yes"}
{"id": "61884845", "revid": "36112485", "url": "https://en.wikipedia.org/wiki?curid=61884845", "title": "Langdon's Legacy", "text": "Langdon's Legacy is a lost 1916 silent comedy-drama film directed by Otis Turner and starring J. Warren Kerrigan and Lois Wilson. It was produced and distributed by Universal Film Manufacturing Company.", "Engineering,_Manufacturing": 0.9995779395, "qwen": "Yes"}
{"id": "61885224", "revid": "36112485", "url": "https://en.wikipedia.org/wiki?curid=61885224", "title": "The Bugler of Algiers", "text": "The Bugler of Algiers is a lost 1916 silent film drama directed by Rupert Julian. It was produced by Universal's Bluebird Photoplays division and distributed by Universal Film Manufacturing Company.\nCast.\n\"unbilled\"", "Engineering,_Manufacturing": 0.9998987913, "qwen": "Yes"}
{"id": "24834390", "revid": "26394783", "url": "https://en.wikipedia.org/wiki?curid=24834390", "title": "Off-axis illumination", "text": "In photolithography, off-axis illumination is an optical system setup in which the incoming light strikes a photomask at an oblique angle rather than perpendicularly to it, that is to say, the incident light is not parallel to the axis of the optical system. \nThe advantages of off-axis illumination can be explained in the context where the pattern on the photomask is a diffraction grating with a small pitch. The light that strikes the diffraction grating is diffracted in various directions. If the light is incident on the grating at the normal angle (along the axis of the optical system), then the zero-th diffracted order light continues to propagate along the optical system axis (as if just passing through the grating without being affected), while the other diffraction orders are diffracted sideways, with the amount of angular deviation increasing as the pitch of the grating is decreasing. (In other words, the light of a non-zero diffraction order propagates from the diffraction grating at a larger angle with respect to the grating optical axis if the grating structure is finer.) For a sufficiently small pitch, only the 0th diffraction order manages to make it through the projection lens (as a lithography machine optical component that images the pattern on the photomask to a photoresist layer on a wafer), with the other orders being lost due to a limited size of the lens (which manufacturing cost goes up as its size becomes larger). The result is that no pattern is created on the wafer, since the 0th diffraction order only contains the average of the photomask pattern.\nBy making the off-axis illumination (i.e., the light is illuminating the mask at an oblique angle), all the diffraction orders from the mask are tilted, which makes it more likely that the higher diffraction orders can make it through the projection lens and help form the image of the mask onto the wafer. ", "Engineering,_Manufacturing": 0.9997789264, "qwen": "Yes"}
{"id": "24845087", "revid": "44835334", "url": "https://en.wikipedia.org/wiki?curid=24845087", "title": "Position-sensing hydraulic cylinder", "text": "A position-sensing hydraulic cylinder is a cylinder with a capability to track its position. \n\"Smart\" hydraulic cylinders.\nInternal LDT.\nIn-cylinder Linear Displacement Transducers (LDTs) are used in mobile equipment. A limitation to most in-cylinder LDTs is that the hydraulic cylinder’s piston rod must be bored through its center to accommodate certain elements of the LDT — usually the waveguide tube of a magnetostrictive transducer. The machining and additional production steps associated with “gun drilling” the piston rod can add cost to the finished cylinder. And although magnetostrictive LDTs provide extremely high accuracy, this accuracy usually is much greater than is needed for most mobile equipment applications.\nInstalling linear position sensors into hydraulic cylinders complicates the production process. CPI has developed a system of sensors which can eliminate the need for gun drilling. \nExternal LDT.\nExternal linear displacement transducers (LDTs) eliminate the need for a hollow hydraulic cylinder rod. Instead, an external sensing “bar” utilizing Hall-Effect technology senses the position of the hydraulic cylinder piston. This is accomplished by the placement of a permanent magnet within the piston. The magnet propagates a magnetic field through the steel wall of the hydraulic cylinder, providing a locating signal to the sensor. \nAdvantages of External LDT:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "24862479", "revid": "46062485", "url": "https://en.wikipedia.org/wiki?curid=24862479", "title": "WorkNC", "text": "WorkNC is a Computer aided manufacturing (CAM) software developed by Sescoi for multi-axis machining.\nHistory.\nThe first version of WorkNC CAM software was released by Sescoi, in 1988. The driving forces behind the product were Bruno Marko, president of Sescoi, and Gerard Billard, R&D Innovation Manager.\nSalomon Group was the first customer to use WorkNC in 1988 in order to manufacture ski boots and other sports equipment.\nIn 2002 the company released WorkNC-CAD, followed by WorkNC 5-axis in 2003 and WorkNC G3 in 2007.\nIn 2008 Sescoi launched WorkXPlore 3D, a collaborative viewer for 3D CAD files that didn't require the original CAD application.\nIn 2009 the company launched WorkNC Dental, a CAD/CAM software for machining of prosthetic appliances, implants or dental structures, as well as WorkNC Wire EDM, a software for Wire EDM.\nIn 2010 Sescoi launched WorkNC-CAD Hybrid Modeling, a 3D CAD software for 3D model design, reparation, machining preparation, and surface design capabilities.\nIn 2010 Sescoi introduced WorkNC Version 21, a 64-bit version with multi-threadingl.\nFunctionality.\nWorkNC CAM main functions include:\nSupported CAD formats.\nWorkNC can read the following CAD file formats: \nProducts.\nWorkNC Dental.\nAutomatic machining of prosthetic appliances, implants, crowns, bridge implants and dental structures.\nIntelligence within the system considers the limitations of the machine tool to automatically produce collision free toolpaths.\nWorkNC MPM (Multi-Part Machining).\nA CAD/CAM module that allows multiple parts to be simultaneously machined on the same machine.\nWorkNC LMP (Layer Milling Process).\nWorkNC LMP is a CAD/CAM software for cutting parts in layers, a well-known technique for machining deep and narrow cavities.\nWorkNC-LMP automatically divides 3D models and creates roughing and finishing toolpaths for each layer. This technology can be used on any machining center, simplifying the programming and cutting of complex shapes by building them up in manageable sections.\nSescoi worked in collaboration with F. Zimmermann, combining the speed and accuracy of the dedicated Zimmermann LMC (Layer Milling Centre) with Sescoi's WorkNC-LMP. By using the software in conjunction with the machine all the toolpaths and special machine control sequences are automatically generated to cut parts in unmanned operation.\nThe LMC works from underneath, using high-speed techniques to machine each layer in turn. As each layer is roughed and finished a new plate is bonded, ready for the next machining operation, this continues until the finished part is built up. WorkNC-LMP automates this process starting from the CAD model, firstly splitting it into layers, and then generating both the roughing and finishing toolpaths for each layer. This technique is ideal for high speed machining enabling the use of short and rigid cutters, and eliminates the possibility of a collision. WorkNC-LMP allows to select the material from a materials library and controls factors such as surface roughening prior to bonding, cutting adhesive channels to control excess glue, overlapping of cutter paths to remove traces of glue, and paths for the application of adhesive between layers. It provides the visual control of all toolpaths and the calculation of the estimated total machining time.\nWorkNC-LMP combines the advantages of generative rapid prototyping with conventional machining, and is the latest example of the company's resolve to make new processes a reality for its customers.\nWorkNC Wire EDM.\nWorkNC Wire EDM is a CAD/CAM software for Wire Electrical discharge machining. Dialog boxes guide the user through the system. Functions within WorkNC Wire EDM allow the extraction of cross sections, ready for 2- or 4-axis cutting. Alternatively, the 3D surfaces of the CAD model can be used directly.\nIt also includes graphical verification to automatically check for collisions and the maximum wire angle possible on each individual EDM machine. The latest version makes it easy to extract and link 4-axis wire paths. Dialog boxes guide the user through the process making it simple to add tags, create roughing and finishing wire paths, lead in and out moves, a range of corner strategies, and tag removal cycles. Postprocessors and technology libraries are included for all leading machines.\nWorkNC-CAD.\nWorkNC-CAD is a manufacturing CAD software with surface and solid modeling functions. It is included free as a standard integrated component of WorkNC. It provides features required to design and manufacture molds, dies, and tooling without the need for additional software applications or outsourcing.\nWorkNC-CAD has advanced intelligent surface morphing for filling simple or complex cavities, automatic 2D feature recognition and cycle definition for drilling, counterboring, reaming and tapping, as well as automatic mold and die core separation.\nWorkNC-CAD Hybrid Modeling.\nWorkNC-CAD Hybrid Modeling (HM) is a 3D CAD software launched by Sescoi in 2010 for 3D model design, reparation and machining preparation, with surface design capabilities integrated with solid modeling functionality in a user friendly environment. It can be used as an independent CAD product. It is powered by D-Cubed software components from Siemens PLM.\nWorkNC-CAD HM works on solid and surface models making use of parametric commands to easily manipulate and repair CAD data. Along with multiple CAD translators, it includes modules for electrode creation, core/cavity separation and Wire EDM. The WorkNC Electrode module makes use of the WorkNC-CAD Hybrid Modeling capabilities to extract electrode shapes directly from solid or surface models. The electrode model can be modified and extended, and tool holders added from a library to produce a complete electrode. WorkNC's collision checking ensures the electrode does not collide with any surrounding surfaces, automatically adding extensions as required. Documentation and electrode coordinate systems are produced by the software to ensure correct positioning for the EDM operations.\nWorkNC-CAD Hybrid Modeling features include:\nWhen used in its standalone design version by toolmakers in their technical departments, it offers mold, tool and die businesses a uniform CAD product throughout the entire manufacturing process.\nWorkXPlore 3D.\nWorkXPlore 3D is a 3D viewer for CAD files. A free viewer version and a free evaluation version are available.", "Engineering,_Manufacturing": 0.9614236355, "qwen": "Yes"}
{"id": "24876073", "revid": "38355450", "url": "https://en.wikipedia.org/wiki?curid=24876073", "title": "Critical Manufacturing", "text": "Critical Manufacturing is a subsidiary of ASM Pacific Technology Limited (ASMPT). It was founded in 2008 and is focused on providing automation and manufacturing software for high-tech industries, such as photovoltaics, electronics and semiconductors. It has offices in Portugal, USA, Germany and China. In 2018, it became a subsidiary of ASM Pacific Technology Limited.\nProducts.\nThe company flagship product is Critical Manufacturing MES, a next-generation manufacturing operations management system.\nCritical Manufacturing MES uses technologies from Microsoft, providing an Internet application user experience.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "69417580", "revid": "14915941", "url": "https://en.wikipedia.org/wiki?curid=69417580", "title": "KORS (shoe factory)", "text": "KORS (also Novosibirsk Shoe Factory, Leather and Shoe Factory named after Kirov) is a shoe factory in Novosibirsk, Russia. It was founded in 1934.\nHistory.\nThe shoe factory was founded in 1934 in Novosibirsk. In 1935 it occupied the building of the former Military Rusk Plant.\nDuring the Great Patriotic War, the factory produced about 7 million pairs of boots for sailors and soldiers; during this period, the enterprise also manufactured ski bindings, mine casings, etc.\nIn 1969 the shoe factory produced over 6 million pairs of shoes (187 models).\nIn 1970–1980 the factory maintained economic ties with India, China, Vietnam, Italy and Yugoslavia.\nIn 1972 and 1984 the plants of hard and chrome leather were reconstructed.\nIn 1988, injection molding machines were put into operation, thanks to which an additional 750 thousand pairs of shoes were manufactured.\nIn the 1990s, the factory was re-equipped. Computer technology appeared at the enterprise.\nCulture.\nIn 1935, the House of Culture named after Kirov was created at the factory. In 1937, the Museum of Labor and Military Glory was founded.\nEven before the Great Patriotic War, the \"Kirovsky Udarnik\" newspaper began to be published. In 1956, the \"Tribuna\" nespaper appears. Since 1995, the factory begins to publish a newsletter.", "Engineering,_Manufacturing": 0.999607265, "qwen": "Yes"}
{"id": "1433442", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=1433442", "title": "Anti-roll bar", "text": "An anti-roll bar (roll bar, anti-sway bar, sway bar, stabilizer bar) is a part of many automobile suspensions that helps reduce the body roll of a vehicle during fast cornering or over road irregularities. It connects opposite (left/right) wheels together through short lever arms linked by a torsion spring. An anti-roll bar increases the suspension's roll stiffness—its resistance to roll in turns—independent of its spring rate in the vertical direction. The first stabilizer bar patent was awarded to Canadian inventor Stephen Coleman of Fredericton, New Brunswick on April 22, 1919.\nAnti-roll bars were unusual on pre-WW2 cars due to the generally much stiffer suspension and acceptance of body roll. From the 1950s on, however, production cars were more commonly fitted with anti-roll bars, especially those vehicles with softer coil spring suspension.\nPurpose and operation.\nAn anti-sway or anti-roll bar is intended to force each side of the vehicle to lower, or rise, to similar heights, to reduce the sideways tilting (roll) of the vehicle on curves, sharp corners, or large bumps. With the bar removed, a vehicle's wheels can tilt away by much larger distances, as shown in the SUV image at right. Although there are many variations in design, a common function is to force the opposite wheel's shock absorber, spring, or suspension rod to lower or rise to a similar level as the other wheel.\nIn a fast turn, a vehicle tends to drop closer onto the outer wheels, and the anti-roll bar soon forces the opposite wheel to also get closer to the vehicle. As a result, the vehicle tends to \"hug\" the road closer in a fast turn, where all wheels are closer to the body. After the fast turn, then the downward pressure is reduced, and the paired wheels can return to their normal height against the vehicle, kept at similar levels by the connecting anti-roll bar.\nBecause each pair of wheels is cross-connected by a bar, the combined operation causes all wheels to generally offset the separate tilting of the others and the vehicle tends to remain level against the general slope of the terrain.\nPrinciples.\nAn anti-roll bar is usually a torsion spring that resists body roll motions. It is usually constructed out of a cylindrical steel bar, formed into a \"U\" shape, that connects to the body at two points, and at the left and right sides of the suspension. If the left and right wheels move together, the bar rotates about its mounting points. If the wheels move relative to each other, the bar is subjected to torsion and forced to twist. Each end of the bar is connected to an \"end link\" through a flexible joint. The anti-roll bar end link connects in turn to a spot near a wheel or axle, transferring forces from a heavily loaded axle to the opposite side.\nForces are therefore transferred:\nThe bar resists the torsion through its stiffness. The stiffness of an anti-roll bar is proportional to the stiffness of the material, the fourth power of its radius, and the inverse of the length of the lever arms (i.e., the shorter the lever arm, the stiffer the bar). Stiffness is also related to the geometry of the mounting points and the rigidity of the bar's mounting points. The stiffer the bar, the more force required to move the left and right wheels relative to each other. This increases the amount of force required to make the body roll.\nIn a turn the sprung mass of the vehicle's body produces a lateral force at the centre of gravity (CG), proportional to lateral acceleration. Because the CG is usually not on the roll axis, the lateral force creates a moment about the roll axis that tends to roll the body. (The roll axis is a line that joins the front and rear roll centers). The moment is called the roll couple.\nRoll couple is resisted by the suspension roll stiffness, which is a function of the spring rate of the vehicle's springs and of the anti-roll bars, if any. The use of anti-roll bars allows designers to reduce roll without making the suspension's springs stiffer in the vertical plane, which allows improved body control with less compromise of ride quality.\nOne effect of body (frame) lean, for typical suspension geometry, is positive camber of the wheels on the outside of the turn and negative on the inside, which reduces their cornering grip (especially with cross ply tires).\nMain functions.\nAnti-roll bars provide two main functions. The first function is the reduction of body lean. The reduction of body lean is dependent on the total roll stiffness of the vehicle. Increasing the total roll stiffness of a vehicle does not change the steady state total load (weight) transfer from the inside wheels to the outside wheels, it only reduces body lean. The total lateral load transfer is determined by the CG height and track width.\nThe other function of anti-roll bars is to tune the handling balance of a car. Understeer or oversteer behavior can be tuned out by changing the proportion of the total roll stiffness that comes from the front and rear axles. Increasing the proportion of roll stiffness at the front increases the proportion of the total load transfer that the front axle reacts to—and decreases the proportion that the rear axle reacts to. In general, this makes the outer front wheel run at a comparatively higher slip angle, and the outer rear wheel to run at a comparatively lower slip angle, which is an understeer effect. Increasing the proportion of roll stiffness at the rear axle has the opposite effect and decreases understeer.\nDrawbacks.\nBecause an anti-roll bar connects wheels on opposite sides of the vehicle, the bar transmits the force of a bump on one wheel to the opposite wheel. On rough or broken pavement, anti-roll bars can produce jarring, side-to-side body motions (a \"waddling\" sensation), which increase in severity with the diameter and stiffness of the anti-roll bars. Other suspension techniques can delay or dampen this effect of the connecting bar.\nExcessive roll stiffness, typically achieved by configuring an anti-roll bar too aggressively, can make the inside wheels lift off the ground during hard cornering. This can be used to advantage: many front wheel drive production cars lift a rear wheel when cornering hard in order to overload the opposite wheel, limiting understeer.\nAdjustable bars.\nSome anti-roll bars, particularly those intended for use in auto racing, are externally adjustable while the car is in the pit whereas some systems can be adjusted in real time by the driver from inside the car, such as in Super GT. This allows the stiffness to be altered, for example by increasing or reducing the length of the lever arms on some systems, or by rotating a flat lever arm from a stiff edge-on position to a more flexible flat-side-on position on other systems. This lets a mechanic tune the roll stiffness for different situations without replacing the entire bar.\nMacPherson struts.\nThe MacPherson strut is a common form of strut suspension. This was not the first attempt at strut suspension, but in MacPherson's original patent, the anti-roll bar forms an integral and essential part of the suspension, in addition to its usual function in controlling body roll. A strut suspension like MacPherson's requires a hinged lower member between the chassis and wheel hub to control the wheel position both inwards and outwards (controlling the track), and also forwards and backwards. This may be provided by a wishbone with a number of joints, or by using an additional radius rod. MacPherson's design replaced the wishbone with a simpler and cheaper track control arm, with a single inboard joint, to control the track. Forward and backward position was controlled through the anti-roll bar. Overall this required a simpler and cheaper set of suspension members than with wishbones, also allowing a reduction in unsprung weight.\nAs the anti-roll bar is required to control wheel position, the bars of a MacPherson strut suspension may be connected through ball joints. However many later \"MacPherson strut\" suspensions have reverted to using wishbones rather than the simplified track control arm of the original design.\nSemi active anti-roll bars.\nVarious methods of decoupling the anti-roll bar have been proposed. The first production car to use an active anti-roll bar was the 1988 Mitsubishi Mirage Cyborg. The \"Dual Mode Suspension\" equipped with the 16-v turbo model has front active anti-roll bar that has a hydraulic actuator built in the anti-roll bar link. The actuator can be operated with a switch on the dash board, changing the effectiveness of the anti-roll bar between the sport mode and touring mode. The Jeep Wrangler (JK, JL) and Jeep Gladiator (JT) also have a switchable decoupler on Rubicon models, to increase wheel articulation for off-roading.\nActive systems.\nThe first car to use an active anti-roll bar in 1994 was the Citroën Xantia Activa, a medium-sized sedan sold in Europe. The SC.CAR (Systeme Citroën de Contrôle Actif du Roulis) system featured an anti-roll bar that could be stiffened under the command of the suspension ECU during hard cornering. The car rolled a maximum of 2 degrees.\nIn 2001 the BMW 7 Series (E65) introduced Active Roll Stabilization (ARS) \"active\" anti-roll bars that can be proportionally controlled automatically by a suspension-control computer, reducing body lean in turns while improving rough-road ride quality.\nIn 2006 Toyota introduced its Active Stabilizer Suspension System. By altering anti-roll bar stiffness, this system acts to reduce body tilt during cornering, keeping the vehicle more level during turns and improving handling, as opposed to the natural tendency of a vehicle to roll due to the lateral forces experienced during high-speed maneuvering. The active stabilizer system relies on vehicle body sensors and electric motors. The first production usage of this system was introduced in August 2005 with the Lexus GS430 sport sedan.\nPorsche Cayenne introduced Porsche Dynamic Chassis Control (PDCC), a system with active roll-bars in 2007 (on European market).\nIn 2011, the third generation Mercedes-Benz M-Class introduced a similar system: ACTIVE CURVE SYSTEM.\nRange Rover Sport introduced Dynamic Response active anti-roll bars.\nMercedes-Benz S-Class Active Body Control system uses another approach: the computer uses sensors to detect lateral load, lateral force, and height difference in the suspension strut, then uses hydraulic pressure to raise or lower the spring to counter roll. This system removes the anti-roll bar. Most active roll control systems allow a small degree of roll to give a more natural feel.\nToyota also uses a mechanical system called Kinetic Dynamic Suspension System (KDSS) that essentially disengages the stabilizer bars when off-road, allowing for greater vehicle articulation and ride quality.", "Engineering,_Manufacturing": 0.9998650551, "qwen": "Yes"}
{"id": "24817815", "revid": "41840956", "url": "https://en.wikipedia.org/wiki?curid=24817815", "title": "Oramir", "text": "Oramir Semiconductor Equipment Ltd. is an Israeli company that develops advanced laser cleaning technologies for semiconductor wafers, used during their manufacturing process. Oramir is located in Rehovot, Israel.\nHistory.\nOramir was founded in 1992 by Fairchild Corporation, Teuza Venture Capital Fund and Rafael Development Corporation of Israel. Oramir was named after Amir Sinai who was killed in service as an IDF special unit NCO in July 1984, during the war in Lebanon. Dan Sinai, Amir's father, was one of Oramir's founders.\nOramir’s notability derives from developing the advanced technology for cleaning silicon wafers in a one step dry process. Particles and other contaminants can be removed from a silicon substrate by a patented laser based technology. Applied Materials Inc. (NASDAQ: AMAT), a semiconductor equipment manufacturer, acquired Oramir for $21 million on June 27, 2001.", "Engineering,_Manufacturing": 0.998467207, "qwen": "Yes"}
{"id": "12562201", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=12562201", "title": "Industrial symbiosis", "text": "Industrial symbiosis a subset of industrial ecology. It describes how a network of diverse organizations can foster eco-innovation and long-term culture change, create and share mutually profitable transactions—and improve business and technical processes.\nAlthough geographic proximity is often associated with industrial symbiosis, it is neither necessary nor sufficient—nor is a singular focus on physical resource exchange. Strategic planning is required to optimize the synergies of co-location. In practice, using industrial symbiosis as an approach to commercial operations—using, recovering and redirecting resources for reuse—results in resources remaining in productive use in the economy for longer. This in turn creates business opportunities, reduces demands on the earth's resources, and provides a stepping-stone towards creating a circular economy. \nIndustrial symbiosis is a subset of industrial ecology, with a particular focus on material and energy exchange. Industrial ecology is a relatively new field that is based on a natural paradigm, claiming that an industrial ecosystem may behave in a similar way to the natural ecosystem wherein everything gets recycled, albeit the simplicity and applicability of this paradigm has been questioned.\nIntroduction.\nEco-industrial development is one of the ways in which industrial ecology contributes to the integration of economic growth and environmental protection. Some of the examples of eco-industrial development are:\nIndustrial symbiosis engages traditionally separate industries in a collective approach to competitive advantage involving physical exchange of materials, energy, water, and/or by-products. The keys to industrial symbiosis are collaboration and the synergistic possibilities offered by geographic proximity\". Notably, this definition and the stated key aspects of industrial symbiosis, i.e., the role of collaboration and geographic proximity, in its variety of forms, has been explored and empirically tested in the UK through the research and published activities of the National Industrial Symbiosis Programme.\nIndustrial symbiosis systems collectively optimize material and energy use at efficiencies beyond those achievable by any individual process alone. IS systems such as the web of materials and energy exchanges among companies in Kalundborg, Denmark have spontaneously evolved from a series of micro innovations over a long time scale; however, the engineered design and implementation of such systems from a macro planner's perspective, on a relatively short time scale, proves challenging.\nOften, access to information on available by-products is difficult to obtain. These by-products are considered waste and typically not traded or listed on any type of exchange. Only a small group of specialized waste marketplaces addresses this particular kind of waste trading.\nExample.\nRecent work reviewed government policies necessary to construct a multi-gigaWatt photovoltaic factory and complementary policies to protect existing solar companies are outlined and the technical requirements for a \"symbiotic industrial system\" are explored to increase the manufacturing efficiency while improving the environmental impact of solar photovoltaic cells. The results of the analysis show that an eight-factory industrial symbiotic system can be viewed as a medium-term investment by any government, which will not only obtain direct financial return, but also an improved global environment.\nThis is because synergies have been identified for co-locating glass manufacturing and photovoltaic manufacturing.\nThe waste heat from glass manufacturing can be used in industrial-sized greenhouses for food production. Even within the PV plant itself a secondary chemical recycling plant can reduce environmental impact while improving economic performance for the group of manufacturing facilities.\nIn DCM Shriram consolidated limited (Kota unit) produces caustic soda, calcium carbide, cement and PVC resins. Chlorine and hydrogen are obtained as by-products from caustic soda production, while calcium carbide produced is partly sold and partly is treated with water to form slurry(aqueous solution of calcium hydroxide) and ethylene. The chlorine and ethylene produced are utilised to form PVC compounds, while the slurry is consumed for cement production by wet process. Hydrochloric acid is prepared by direct synthesis where the pure chlorine gas can be combined with hydrogen to produce hydrogen chloride in the presence of UV light.", "Engineering,_Manufacturing": 0.9995754361, "qwen": "Yes"}
{"id": "25155005", "revid": "1165924360", "url": "https://en.wikipedia.org/wiki?curid=25155005", "title": "Automatic lubrication system", "text": "An automatic lubrication system (ALS), sometimes referred to as a centralized lubrication system (CLS), is a system that delivers controlled amounts of lubricant to multiple locations on a machine while the machine is operating. Even though these systems are usually fully automated, a system that requires a manual pump or button activation is still identified as a centralized lubrication system. The system can be classified into two different categories that can share a lot of the same components.\nOil systems: Oil systems primary use is for stationary manufacturing equipment such as CNC milling\nGrease systems: Grease primary use is on mobile units such as trucks, mining or construction equipment.\nAutomatic lubrication systems are key aspects in maintenance and reliability programs. They supply lube points with metered amounts of grease or oil from a central location. The pump supplies the system with the chosen lubricant and is fed from a reservoir that is easily accessible. Depending on the application, the reservoir ranges in size and can be as small as 2 liters all the way up to an intermediate bulk container or even a bulk tank. The options are almost limitless and are application-specific. These systems have the option to be monitored remotely with feedback and can be tied directly into your plant's PLC. So whether you're running an excavator, driving a ready-mix truck, operating a crusher, or making steel, you can rest assured that your assets are being properly lubricated at all times.\nReasons for Automatic Lubrication Systems.\nAutomatic lubrication systems or centralized lubrication system s are designed to apply lubricant in precise, metered amounts over short, frequent time intervals. Time and human resource constraints and often the physical location on the machine often makes it impractical to manually lubricate the points. As a result, production cycles, machine availability, and manpower availability dictate the intervals at which machinery is lubricated, which is not optimal for the point requiring lubrication. Automatic lubrication systems are installed on machinery to circumvent these issues.\nBenefits.\nAuto lube systems have many advantages over traditional methods of manual lubrication:\nComponents.\nA typical system consists of controller/timer, pump w/reservoir, supply line, metering valves, and feed lines. Regardless of the manufacturer or type of system, all automatic lubrication systems share these 5 main components:\nTypes.\nThere are several different types of automatic lubrication systems including:\nThe 4 most commonly used Automatic Lubrication System types are:\nSingle line progressive.\nA single line progressive system uses lubricant flow to cycle individual metering valves and valve assemblies. The valves consist of dispensing pistons moving back and forth in a specific bore. Each piston depends on flow from the previous piston to shift and displace lubricant. If one piston doesn't shift, none of the following pistons will shift. Valve output is not adjustable.\nOperation begins when the controller/timer sends a signal to the pump to start the lube event. The pump then feeds lubricant into the supply line which connects to the primary metering valve, for either a preprogrammed amount of time or number of times as monitored through a designated piston cycle switch. Lubricant is fed to the multiple lubrication points one after another via secondary progressive metering valves sized for each series of lubrication points, and then directly to each point via the feed lines.\nSingle line parallel.\nThe first single-line parallel system for industry was introduced in 1937 by Lincoln Engineering (now known as Lincoln Industrial) in the United States.\nA single line parallel system can service a single machine, different zones on a single machine or even several separate machines and is ideal when the volume of lubricant varies for each point. In this type of system, a central pump station automatically delivers lubricant through a single supply line to multiple branches of injectors. Each injector serves a single lubrication point, operates independently and may be individually adjusted to deliver the desired amount of lubricant.\nOperation begins when the controller/timer sends a signal to the pump starting the lube cycle. The pump begins pumping lubricant to build up pressure in the supply line connecting the pump to the injectors. Once the required pressure is reached, the lube injectors dispense a predetermined amount of lubricant to the lubrication points via feed lines.\nOnce the entire system reaches the required pressure, a pressure switch sends a signal to the controller indicating that grease has cycled through to all the distribution points. The pump shuts off. Pressure is vented out of the system and grease in the line is redirected back to the pump reservoir, until the normal system pressure level is restored.\nDual line parallel.\nA dual line parallel system is similar to the single line parallel system in that it uses hydraulic pressure to cycle adjustable valves to dispense measured shots of lubricant. It has 2 main supply lines which are alternatively used as pressure / vent lines. The advantage of a two-line system is that it can handle hundreds of lubrication points from a single pump station over several thousand feet using significantly smaller tubing or pipe.\nOperation begins when the controller/timer sends a signal to the pump to start the lubrication cycle. The pump begins pumping lubricant to build up pressure in the first (the pressure) supply line while simultaneously venting the second (vent) return line. Once the required pressure is reached, a predetermined amount of lubricant is dispensed by the metering devices to half of the lubrication points via feed lines.\nOnce the pressure switch monitoring main supply line pressure indicates a preset pressure in the line has been reached, the system is hydraulically closed. The controller shuts off the pump and signals a changeover valve to redirect lubricant to the second main supply line.\nThe next time the controller activates the system, the second main line now becomes the pressure line while the first line becomes the vent line. The second line is pressurized and the entire process is repeated lubricating the remaining lube points.\nMulti point direct lubricator\nWhen the controller in the pump or external controller activates the drive motor, a set of cams turns and activates individual injectors or pump elements to dispense a fixed amount of lubricant to each individual lubrication point. Systems are easy to design, direct pump to lube point without added accessories and easy to troubleshoot.", "Engineering,_Manufacturing": 1.0000025034, "qwen": "Yes"}
{"id": "5757742", "revid": "1165352791", "url": "https://en.wikipedia.org/wiki?curid=5757742", "title": "Polishing (metalworking)", "text": "Polishing and buffing are finishing processes for smoothing a workpiece's surface using an abrasive and a work wheel or a leather strop. Technically, \"polishing\" refers to processes that uses an abrasive that is glued to the work wheel, while \"buffing\" uses a loose abrasive applied to the work wheel. Polishing is a more aggressive process, while buffing is less harsh, which leads to a smoother, brighter finish. A common misconception is that a polished surface has a mirror-bright finish, however, most mirror-bright finishes are actually buffed.\nPolishing is often used to enhance the appearance of an item, prevent contamination of instruments, remove oxidation, create a reflective surface, or prevent corrosion in pipes. In metallography and metallurgy, polishing is used to create a flat, defect-free surface for examination of a metal's microstructure under a microscope. Silicon-based polishing pads or a diamond solution can be used in the polishing process. Polishing stainless steel can also increase its sanitary benefits.\nThe removal of oxidization (tarnish) from metal objects is accomplished using a metal polish or tarnish remover; this is also called polishing. To prevent further unwanted oxidization, polished metal surfaces may be coated with wax, oil, or lacquer. This is of particular concern for copper alloy products such as brass and bronze.\nWhile used less extensively than traditional mechanical polishing, electropolishing is an alternative form of polishing that uses the principles of electrochemistry to remove microscopic layers of metal from a base surface. This method of polishing can be fine-tuned to give a wide range of finishes, from matte to mirror-bright. Electropolishing also has an advantage over traditional manual polishing in that the finished product will not experience the compression and deformation traditionally associated with the polishing process.\nProcess.\nThe condition of the material at hand determines what type of abrasive will be applied. The first stage, if the material is unfinished, starts with a rough abrasive (perhaps 60 or 80 grit) and each subsequent stage uses a finer abrasive, such as 120, 180, 220/240, 320, 400 and higher grit abrasives, until the desired finish is achieved. The rough (i.e. large grit) passes remove imperfections within the metal surface like pits, nicks, lines and scratches. The finer abrasives leave progressively finer lines that are not visible to the naked eye. A no. 8 (\"mirror\") finish requires polishing and buffing compounds, and polishing wheels attached to high speed polishing machines or electric drills. Lubricants like wax and kerosene may be used as lubricating and cooling media during these operations, although some polishing materials are specifically designed to be used \"dry.\" Buffing may be done by hand with a stationary polisher or die grinder, or it may be automated using specialized equipment.\nWhen buffing there are two types of buffing motions: the \"cut motion\" and the \"color motion\". The cut motion is designed to give a uniform, smooth, semi-bright surface finish. This is achieved by moving the workpiece against the rotation of the buffing wheel, while using medium to hard pressure. The color motion gives a clean, bright, shiny surface finish. This is achieved by moving the workpiece with the rotation of the buffing wheel, while using medium to light pressure.\nWhen polishing brass (a softer metal) there are often minute marks in the metal caused by impurities. To smooth out the finer marks, the surface is polished with a very fine (600) grit, copper plated, then buffed to a mirror finish with an airflow mop.\nPolishing operations for items such as chisels, hammers, screwdrivers, wrenches, etc., are given a fine finish but not plated. In order to achieve this finish four operations are required: roughing, dry fining, greasing, and coloring. Note that roughing is usually done on a solid grinding wheel and for an extra fine polish the greasing operation may be broken up into two operations: rough greasing and fine greasing. However, for inexpensive items money is saved by only performing the first two operations.\nPolishing knives and cutlery is known as fine glazing or blue glazing. Sand buffing, when used on German silver, white metal, etc., is technically a buffing operation because it uses a loose abrasive, but removes a significant amount of material, like polishing.\nEquipment.\nWhite and grey aluminium oxide abrasives are used on high tensile strength metals, such as carbon and alloy steel, tough iron, and nonferrous alloys. Gray silicon carbide abrasives are used on hard and brittle substances, such as grey iron and cemented carbide, and low tensile strength metals, such as brass, aluminium, and copper. Green chromium(III) oxide is the abrasive used in green compounds that are typically used to finish ferrous metals (steels).\nPolishing wheels come in a wide variety of types to fulfil a wide range of needs. The most common materials used for polishing wheels are wood, leather, canvas, cotton cloth, plastic, felt, paper, sheepskin, impregnated rubber, canvas composition, and wool; leather and canvas are the most common. Wooden wheels have emery or other abrasives glued onto them and are used to polish flat surfaces and maintain good edges. There are many types of cloth wheels. Cloth wheels that are cemented together are very hard and used for rough work, whereas other cloth wheels that are sewn and glued together are not as aggressive. There are cloth wheels that are not glued or cemented, and instead are sewn and have metal side plates for support. Solid felt wheels are popular for fine finishes. Hard roughing wheels can be made by cementing together strawboard paper disks. Softer paper wheels are made from felt paper. Most wheels are run at approximately 7500 surface feet per minute (SFM), however muslin, felt and leather wheels are usually run at 4000 SFM.\nBuffing wheels, also known as mops, are either made from cotton or wool cloth and come bleached or unbleached. Specific types include: sisal, spiral sewn, loose cotton, canton flannel, domet flannel, denim, treated spiral sewn, cushion, treated vented, untreated vented, string buff, finger buff, sisal rope, mushroom, facer, tampered, scrubbing mushroom, hourglass buff, rag, \"B\", climax, swansdown, airflow, coolair, and bullet.\nThe following chart will help in deciding which wheels and compounds to use when polishing different materials. This chart is a starting point and experienced polishers may vary the materials used to suit different applications.\nApplications.\nPolishing may be used to enhance and restore the looks of certain metal parts or object on cars and other vehicles, handrails, cookware, kitchenware, and architectural metal. In other applications such as pharmaceutical, dairy, and specialty plumbing, pipes are buffed to help prevent corrosion and to eliminate locations where bacteria or mold may reside. Buffing is also used to manufacture light reflectors.", "Engineering,_Manufacturing": 1.0000038147, "qwen": "Yes"}
{"id": "21609404", "revid": "1063749", "url": "https://en.wikipedia.org/wiki?curid=21609404", "title": "Tolerance analysis", "text": "Tolerance analysis is the general term for activities related to the study of accumulated variation in mechanical parts and assemblies. Its methods may be used on other types of systems subject to accumulated variation, such as mechanical and electrical systems. Engineers analyze tolerances for the purpose of evaluating geometric dimensioning and tolerancing (GD&T). Methods include 2D tolerance stacks, 3D Monte Carlo simulations, and datum conversions.\nTolerance stackups or tolerance stacks are used to describe the problem-solving process in mechanical engineering of calculating the effects of the accumulated variation that is allowed by specified dimensions and tolerances. Typically these dimensions and tolerances are specified on an engineering drawing. Arithmetic tolerance stackups use the worst-case maximum or minimum values of dimensions and tolerances to calculate the maximum and minimum distance (clearance or interference) between two features or parts. Statistical tolerance stackups evaluate the maximum and minimum values based on the absolute arithmetic calculation combined with some method for establishing likelihood of obtaining the maximum and minimum values, such as Root Sum Square (RSS) or Monte-Carlo methods.\nModeling.\nIn performing a tolerance analysis, there are two fundamentally different analysis tools for predicting stackup variation: worst-case analysis and statistical analysis.\nWorst-case.\nWorst-case tolerance analysis is the traditional type of tolerance stackup calculation. The individual variables are placed at their tolerance limits in order to make the measurement as large or as small as possible. The worst-case model does not consider the distribution of the individual variables, but rather that those variables do not exceed their respective specified limits. This model predicts the maximum expected variation of the measurement. Designing to worst-case tolerance requirements guarantees 100 percent of the parts will assemble and function properly, regardless of the actual component variation. The major drawback is that the worst-case model often requires very tight individual component tolerances. The obvious result is expensive manufacturing and inspection processes and/or high scrap rates. Worst-case tolerancing is often required by the customer for critical mechanical interfaces and spare part replacement interfaces. When worst-case tolerancing is not a contract requirement, properly applied statistical tolerancing can ensure acceptable assembly yields with increased component tolerances and lower fabrication costs.\nStatistical variation.\nThe statistical variation analysis model takes advantage of the principles of statistics to relax the component tolerances without sacrificing quality. Each component's variation is modeled as a statistical distribution and these distributions are summed to predict the distribution of the assembly measurement. Thus, statistical variation analysis predicts a distribution that describes the assembly variation, not the extreme values of that variation. This analysis model provides increased design flexibility by allowing the designer to design to any quality level, not just 100 percent.\nThere are two chief methods for performing the statistical analysis. In one, the expected distributions are modified in accordance with the relevant geometric multipliers within tolerance limits and then combined using mathematical operations to provide a composite of the distributions. The geometric multipliers are generated by making small deltas to the nominal dimensions. The immediate value to this method is that the output is smooth, but it fails to account for geometric misalignment allowed for by the tolerances; if a size dimension is placed between two parallel surfaces, it is assumed the surfaces will remain parallel, even though the tolerance does not require this. Because the CAD engine performs the variation sensitivity analysis, there is no output available to drive secondary programs such as stress analysis. \nIn the other, the variations are simulated by allowing random changes to geometry, constrained by expected distributions within allowed tolerances with the resulting parts assembled, and then measurements of critical places are recorded as if in an actual manufacturing environment. The collected data is analyzed to find a fit with a known distribution and mean and standard deviations derived from them. The immediate value to this method is that the output represents what is acceptable, even when that is from imperfect geometry and, because it uses recorded data to perform its analysis, it is possible to include actual factory inspection data into the analysis to see the effect of proposed changes on real data. In addition, because the engine for the analysis is performing the variation internally, not based on CAD regeneration, it is possible to link the variation engine output to another program. For example, a rectangular bar may vary in width and thickness; the variation engine could output those numbers to a stress program which passes back peak stress as a result and the dimensional variation be used to determine likely stress variations. The disadvantage is that each run is unique, so there will be variation from analysis to analysis for the output distribution and mean, just like would come from a factory. \nWhile no official engineering standard covers the process or format of tolerance analysis and stackups, these are essential components of good product design. Tolerance stackups should be used as part of the mechanical design process, both as a predictive and a problem-solving tool. The methods used to conduct a tolerance stackup depend somewhat upon the engineering dimensioning and tolerancing standards that are referenced in the engineering documentation, such as American Society of Mechanical Engineers (ASME) Y14.5, ASME Y14.41, or the relevant ISO dimensioning and tolerancing standards. Understanding the tolerances, concepts and boundaries created by these standards is vital to performing accurate calculations.\nTolerance stackups serve engineers by:\nConcept of Tolerance vector loop.\nThe starting point for the tolerance loop; typically this is one side of an intended gap, after pushing the various parts in the assembly to one side or another of their loose range of motion. Vector loops define the assembly constraints that locate the parts of the assembly relative to each other. The vectors represent the dimensions that contribute to tolerance stackup in the assembly. The vectors are joined tip-to-tail, forming a chain, passing through each part in the assembly in succession. A vector loop must obey certain modeling rules as it passes through a part. It must:\nAdditional modeling rules for vector loops include: \nThe above rules will vary depending on whether 1D, 2D or 3D tolerance stackup method is used.\nConcerns with tolerance stackups.\nA safety factor is often included in designs because of concerns about:", "Engineering,_Manufacturing": 0.9999922514, "qwen": "Yes"}
{"id": "49681580", "revid": "24902", "url": "https://en.wikipedia.org/wiki?curid=49681580", "title": "Tuuli Mattelmäki", "text": "Tuuli Mattelmäki (1965) is Finnish industrial designer, researcher and lecturer, working and publishing in service design and human centred design.\nTuuli Mattelmäki works as a researcher and project manager at the Aalto University School of Arts, Design and Architecture where she is an associate professor at the Department of Design. She is also a team leader at Encore: Aalto University collaborative design research project.\nAs an industrial designer she has applied her design thinking skills in enhancing innovative approaches that are inspired by the richness of human experiences and everyday practices.\nDuring her research she has worked on several projects for developing tools and processes for user-centred product concept design. Starting point for her research is an empathic design and explorative methods in user-centred design, design probes in particular. She has been actively involved in several user focus case studies and collaborations with the partner companies.\nHer current research concerns creative co-design methods in design for services, as well as the new application contexts of design approaches. Her research with design probes has inspired students and organisations to apply the approach in various projects.\nHer publications include articles about probes, empathic design and design for user experience.\n“Design Probes\", her dissertation from University of Art and Design in Helsinki from 2006, presents a step-by-step overview of the cultural probes method and its history and offers nearly 200 pages of richly illustrated examples, history and theory.", "Engineering,_Manufacturing": 0.9952459931, "qwen": "Yes"}
{"id": "49704067", "revid": "24902", "url": "https://en.wikipedia.org/wiki?curid=49704067", "title": "Seiichi Nakajima", "text": "Seiichi Nakajima (1919–April 11, 2015) was a Japanese citizen and pioneering founder of the Total Productive Maintenance system. He established the PM Awards (currently the TPM Awards).\nNakajima was honored by the Emperor of Japan with the Ranju Ho-sho, or Medal with Blue Ribbon. The award recognizes individuals with significant lifetime achievements, and was given to Nakajima by the Emperor \"to show gratitude for the dedication to improving the manufacturing industry through TPM.\"", "Engineering,_Manufacturing": 0.9999637604, "qwen": "Yes"}
{"id": "71816820", "revid": "4808759", "url": "https://en.wikipedia.org/wiki?curid=71816820", "title": "Renault Sherpa 5", "text": "Renault Sherpa 5 is a tactical military truck made by Renault Trucks Defense, a subsidiary of Renault Trucks. It evolved from the Renault GBC 180.\nDescription.\nRenault Sherpa 5 was debuted at the 2004 Eurosatory military trade fair. The vehicle is an all-wheel drive truck (in 4×4 or 6×6 configurations) that can carry a payload of seven tons. It is used for transport in war zones - the French armed forces use the truck as a chassis for the CAESAR self-propelled howitzer.", "Engineering,_Manufacturing": 0.822804451, "qwen": "Yes"}
{"id": "1956968", "revid": "1144589932", "url": "https://en.wikipedia.org/wiki?curid=1956968", "title": "Schedule (workplace)", "text": "A schedule, often called a rota or roster, is a list of employees, and associated information e.g. location, department, working times, responsibilities for a given time period e.g. week, month or sports season. \nA schedule is necessary for the day-to-day operation of many businesses e.g. retail store, manufacturing facility and some offices. The process of creating a schedule is called scheduling. An effective workplace schedule balances the needs of stakeholders such as management, employees and customers.\nA \"daily\" schedule is usually ordered chronologically, which means the first employees working that day are listed at the top, followed by the employee who comes in next, etc. A \"weekly\" or \"monthly\" schedule is usually ordered alphabetically, employees being listed on the left hand side of a grid, with the days of the week on the top of the grid. In shift work, a schedule usually employs a recurring shift plan.\nA schedule is most often created by a manager. In larger operations, a human resources manager or scheduling specialist may be solely dedicated to creating and maintaining the schedule. A schedule by this definition is sometimes referred to as workflow.\nSoftware is often used to enable organizations to better manage staff scheduling. Organizations commonly use spreadsheet software or employee scheduling software to create and manage shifts, assignments, and employee preferences. For large organisations employee scheduling can be complex, and optimising this is framed as the nurse scheduling problem in operations Research. Advanced employee scheduling software also provides ways to connect with the staff, ask for their preferences and communicate the schedule to them.\nOn-call scheduling.\nAn oncall shift, or on-call scheduling, is a practice that requires employees to be available to be called onto last-minute shifts without pre-scheduling. In the United States, the practice has been opposed by labor rights groups as \"unfair and detrimental to employees.\"\nSelf-scheduling.\nFlexible self-scheduling is a practice used when a manager defines scheduling needs based on demand, but allows employees to select, trade, and fill shifts themselves. Allowing schedules to be created faster, with less effort, and gives hourly employees more control over their work life. ", "Engineering,_Manufacturing": 0.7885408401, "qwen": "Yes"}
{"id": "1957084", "revid": "28457570", "url": "https://en.wikipedia.org/wiki?curid=1957084", "title": "Store manager", "text": "A retail manager (or store manager) is the person ultimately responsible for the day-to-day operations (or management) of a retail store. All employees working in the store report to the retail/store manager. A store manager reports to a district/area or general manager.\nRoles and responsibilities.\nResponsibilities of a store manager include:\nSales generation.\nA store manager must meet the monthly, quarterly, or annual sales goals, depending on the company's fiscal cycle. This involves setting individual sales goals (quotas), holding contests for employees, or offering sales promotions. The manager may also find ways to make employees more productive to meet the goals. Thus, the store manager may be forced to reduce payroll expenditures by decreasing employees' hours, or otherwise reducing operating cost. A store manager should motivate their team to achieve the target set for the store. A store manager should set an example for their subordinates to follow.\nSafety and security.\nThe Store manager is the store's primary key-holder and may be called to the store before, during, or after business hours in the event of an emergency. They are also responsible for the safety of all customers and employees on store premises. Store managers may be required to hold safety meetings, especially as dictated by union practices in cases where store employees belong to a union.\nDivision of responsibility.\nA store manager may have several subordinates who have management-level responsibility. These employees may be called deputy managers, assistant managers, department managers, supervisors, key holders, shift leads, or leads. Sometimes members of the management team may be several grades below the store manager. One example would be store manager - deputy manager - department manager - department leads.\nA store manager has over-all responsibility for all day-to-day activity of the store. Managing & controlling staff, and planning are essential points of the store manager.\nHiring, training and development.\nThe store manager is responsible for hiring, training, and in some cases, development of employees. The manager must ensure staffing levels are adequate to effectively operate the store, and ensure employees receive training necessary for their job responsibilities. Managers may be responsible for developing employees so the company can promote employees from within and develop future leaders, potentially for employment at other locations. Store managers also have the fire powers to any under-performing or misbehaving employees. The role of store managers with regards to the other employees varies from company to company and each respective company's operating methods but in general a store manager will be required to deal with and try to solve any and all problems that may occur at any given time", "Engineering,_Manufacturing": 0.8728958368, "qwen": "Yes"}
{"id": "35304616", "revid": "45488630", "url": "https://en.wikipedia.org/wiki?curid=35304616", "title": "Spherical roller bearing", "text": "A spherical roller bearing is a rolling-element bearing that permits rotation with low friction, and permits angular misalignment. Typically these bearings support a rotating shaft in the bore of the inner ring that may be misaligned in respect to the outer ring. The misalignment is possible due to the spherical internal shape of the outer ring and spherical rollers. Despite what their name may imply, spherical roller bearings are not truly spherical in shape. The rolling elements of spherical roller bearings are mainly cylindrical in shape, but have a (barrel like) profile that makes them appear like cylinders that have been slightly over-inflated (i.e. like a barrel).\nConstruction.\nSpherical roller bearings consist of an inner ring with two raceways inclined at an angle to the bearing axis, an outer ring with a common spherical raceway, spherical rollers, cages and, in certain designs, also internal guide rings or center rings. These bearings can also be sealed.\nHistory.\nThe spherical roller bearing was invented by engineer Arvid Palmgren and was introduced on the market 1919 by SKF. The design of the bearing that Arvid Palmgren invented is similar to the design that is still in use in modern machines.\nDesigns.\nMost spherical roller bearings are designed with two rows of rollers, allowing them to take very heavy radial loads and heavy axial loads. There are also designs with one row of rollers, suitable for lower radial loads and virtually no axial load. These are also called \"barrel roller bearings\" or \"Tonnenlager\" and are typically available in the 202- and 203-series.\nThe internal design of the bearing is not standardised by ISO, so it varies between different manufacturers and different series. Some features that may or may not exist in different bearings are:\nDimensions.\nExternal dimensions of spherical roller bearings are standardised by ISO in the standard ISO 15:1998. Some of the common series of spherical roller bearings are: 213, 222, 223, 230, 231, 232, 238, 239, 240, 241, 248, 249.\nMaterials.\nBearing rings and rolling elements can be made of a number of different materials, but the most common is \"chrome steel\", (high carbon chromium) a material with approximately 1.5% chrome content. Such \"chrome steel\" has been standardized by a number of authorities, and there are therefore a number of similar materials, such as: AISI 52100 (USA), 100CR6 (Germany), SUJ2 (Japan) and GCR15 (China).\nSome common materials for bearing cages:\nThe choice of material is mainly done by the manufacturing volume and method. For large-volume bearings, cages are often of stamped sheet-metal or injection molded polyamide, whereas low volume manufacturers or low volume series often have cages of machined brass or machined steel. For some specific applications, special material for coating (e.g. PTFE coated cylindrical bore for vibratory applications) is adopted.\nManufacturers.\nSome manufacturers of \"spherical roller bearings\" are SKF, Schaeffler, Timken Company, NSK Ltd., NTN Corporation and JTEKT.\nSince SKF introduced the spherical roller bearing in 1919, spherical roller bearings have purposefully been refined through the decades to improve carrying capacity and to reduce operational friction. This has been possible by playing with a palette of parameters such as materials, internal geometry, tolerance and lubricant. Nowadays, spherical roller bearing manufacturers are striving to refine the bearing knowledge towards more environmentally-friendly and energy-efficient solutions.\nApplications.\nSpherical bearings are used in countless industrial applications where there are heavy loads, moderate speeds and possibly misalignment. Some common application areas are:", "Engineering,_Manufacturing": 0.9997063875, "qwen": "Yes"}
{"id": "57663376", "revid": "21071050", "url": "https://en.wikipedia.org/wiki?curid=57663376", "title": "Harvey Rosten Award for Excellence", "text": "The Harvey Rosten Award for Excellence is an annual award celebrating a piece of work by a group or individual representing an advance in thermal analysis of electronics equipment or components. Including experiments aimed at specifically validating numerical models.\nThe award is named after Dr. Harvey Rosten, founder of Flomerics, in honor of the influence on the electronics cooling industry he had. The award was curated the year after his death by (1998). The award is announced at the annual SEMI-THERM conference.\nTo be eligible, submitted papers must be an original pieces of work as well as in the public domain. The work must also be relevant, concerning advances in thermal analysis or thermal modelling of electronics equipment or component and have clear application to practical electronics thermal design.\nCriteria.\nTo be eligible, submitted papers must be an original pieces of work as well as in the public domain. The work must also be relevant, concerning advances in thermal analysis or thermal modelling of electronics equipment or component and have clear application to practical electronics thermal design.\nFavourable consideration is administered towards papers that either demonstrate an innovative approach to embodying the understanding of the physical processes affecting the thermal behaviour of an electronics component, part or system, insights into these processes, or a practical application of the advance.", "Engineering,_Manufacturing": 0.9877219796, "qwen": "Yes"}
{"id": "57687305", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=57687305", "title": "Dissimilar friction stir welding", "text": "Dissimilar friction stir welding (DFSW) is the application of friction stir welding (FSW), invented in The Welding Institute (TWI) in 1991, to join different base metals including aluminum, copper, steel, titanium, magnesium and other materials. It is based on solid state welding that means there is no melting. DFSW is based on a frictional heat generated by a simple tool in order to soften the materials and stir them together using both tool rotational and tool traverse movements. In the beginning, it is mainly used for joining of aluminum base metals due to existence of solidification defects in joining them by fusion welding methods such as porosity along with thick Intermetallic compounds. DFSW is taken into account as an efficient method to join dissimilar materials in the last decade. There are many advantages for DFSW in compare with other welding methods including low-cost, user-friendly, and easy operation procedure resulting in enormous usages of friction stir welding for dissimilar joints. Welding tool, base materials, backing plate (fixture), and a milling machine are required materials and equipment for DFSW. On the other hand, other welding methods, such as Shielded Metal Arc Welding (SMAW) typically need highly professional operator as well as quite expensive equipment. \nPrinciple of operation.\nThe mechanism of DFSW is very simple. A rotating tool plunges into the interface of parent metals, and heat input generated by the friction between the tool shoulder surface and top surface of the base metals lead to softening of the base materials. In other words, the rotational movement of the tool mixes and stirs the parent metals and create a softened pasty mixture. Afterwards, the tool's traverse movement along the interface creates a joint. This results in a final bond that combines both mechanical and metallurgical bonding at the interface. These two bondings are critical in order to achieve proper mechanical properties. Butt and lap designs are the most common joint types in dissimilar friction stir welding (DFSW). Likewise, one material is generally harder than the other. In general, hard and soft materials are placed in advancing and retreating sides respectively during welding.\nTool Geometry.\nTool configuration is an important factor to achieve a sound joint. The tool consists of two parts including tool shoulder and tool pin, as shown in below figure. The tool shoulder generates frictional heat, while the tool pin stirs the softened materials. Various pin and shoulder configurations may be used for DFSW. \"Cylindrical\", \"rectangular\", \"triangular\" and \"threaded-cylindrical\" are the most common tool pin profiles, while \"featureless\" and \"scrolled\" are the most common tool shoulder configurations. Tool material selection is dependent on the base materials to be joined. For example, for aluminum/copper joints, hot working alloy steel is generally used, while for harder metals such as titanium/aluminum joints, tungsten carbide is common.\nWelding Parameters.\nIn DFSW, mechanical properties mainly include tensile strength, hardness, yield strength, elongation. Selecting optimum welding parameters results in achieving proper mechanical properties of the joint. Tool rotational speed (rpm), tool traverse speed (mm/min), tool tilt angle (degree), tool offset (mm), tool penetration (mm), and tool geometry are most important welding parameters in DFSW. The tool center is typically placed in the centerline of the joint for similar joints such as aluminum/aluminium or copper/copper joints; in contrast, it is shifted towards the softer materials in DFSW called \"tool offset\". It is a significant factor to achieve a joint possessing smaller welding defect and higher mechanical properties. Generally, harder and softer materials are placed in Advancing Side (AS) and Retreating Side (RT) respectively. Regardless of the tool geometry, which plays a critical role on final mechanical and metallurgical properties of the weldment, the effect of the tool rotational speed and tool offset are taken into account as the most important welding parameters during DFSW.\nHeat Generation.\nA non-consumable rotating tool is plunged into the interface of parent materials. Frictional heat arisen from the tool shoulder throughout welding plasticizes the parent materials leading to local plastic deformation of the parent materials. Localized heat generated by the tool results from following process. At the initial stage, it is primarily arisen from frictional heat between the plunged pin and parent materials. Afterwards, it is mainly produced by the frictional heat between the shoulder surface and the top-surface of base metals once the shoulder touched the top-surface. Subsequently, the softened materials are stirred together by the rotating pin resulting in a solid-state bond. Frigaard et al. showed that tool rotational speed and tool shoulder diameters are the main contributing factors in heat generation.\nMaterial Flow.\nThe mechanism of bonding in DFSW is based on two simple concepts. First, stirred materials, a mixture flow of soft and hard metals, is forged into the interface of harder material leading to strong mechanical bond at the interface. Furthermore, a complementary metallurgical bond is formed at the interface enhancing and improving mechanical properties of the joint. Materials flow throughout DFSW depends on various parameters including welding process parameters, tool geometry, and base materials. Tool geometry is the most important factor in achieving appropriate material flow.\nDefects.\nOccurrence of welding defects in DFSW are quite common. Welding defects in DFSW include tunneling defect, fragment defect, crack, void, surface cavity or grooves and excessive flash formation. Amongst these, tunneling defect is the most common defect in DFSW resulting from improper material flows throughout welding. It is mainly attributed to inappropriate selection of welding parameters particularly welding speed, rotational speed, tool design and tool penetration leading to either abnormal stirring or insufficient heat input. Formation of coarse fragments of harder materials within the matrix of softer materials is another typical defect observed only in DFSW. Generally, during DFSW, the paste materials behave like a metal matrix composite such that harder and softer materials act as the matrix and the reinforcement respectively. In fact, it is quite important to keep the harder material in relatively small size in order to achieve the best flow of materials. Therefore, any factors that cause formation of large piece of harder material lead to appearance of fragment defects. Tool offset and tool pin design were taken into account as the most significant contributing factors in formation of fragment defect in DFSW. They were accounted for disturbing the flow of material resulting from the formation of large pieces of harder material within the matrix of softer material due to the fact that it is quite difficult to stir and mix paste materials when one of them is not relatively fine. In addition, fragment defects usually accompany with other defects such as voids and cracks.\nTypical Characteristics.\nDFSW shows various characteristics in terms of hardness distribution, tensile strength, microstructure, formation of intermetallic compounds as well as formation of a composite structure within the stir zone. The majority of the dissimilar joints fabricated by FSW demonstrate similar results.\nHardness.\nSince the base materials have different mechanical properties, the hardness distribution is not homogeneous which can be attributed to two different reasons. First, different mechanical properties of base materials including the hardness causes inhomogeneity in the weldments. Second, different microstructure and grain size of the welding zones including stir zone, TMAZ, and HAZ result in various hardness. Moreover, the hardness in the nugget zone or stir zone is very inhomogenous because of the formation of onion ring (composite structure ) and IMCs. As a result, dissimilar joints shows inhomogenous distribution in the nugget zone or stir zone.\nMicrostructure.\nFour different welding zones including Stir Zone (SZ) or nugget zone, Thermo-Mechanical Affected Zone (TMAZ), Heat affected zone (HAZ) and Base Metals (BM) are typically observed in dissimilar joints made by FSW. Microstructure of the weldment demonstrates a remarkable grain refinement in the stir zone along with elongation of the grains in the TMAZ. Intensive plastic deformation risen up by tool action, rotational and traverse movements, account for the notable grain refinement in the stir zone. Moreover, HAZ presents relatively coarser grain that can be attributed to lower cooling rate in comparison with other welding areas. Some phenomena are typical in dissimilar friction stir welding including formation of Intermetallic Compounds (IMCs) and appearance of a Composite-like Structure (CS) appeared in various patterns specifically onion rings shown in below figure. IMCs and CS enhance mechanical behavior of the joints depending their conditions such as the thickness of IMCs as well as distribution pattern of composite-like structure. Proper selection of welding parameters optimizes formation of IMCs and CS resulting in the highest mechanical properties. As pointed out before, rotational speed, welding speed, and tool offset along with tool pin are the most important factors affecting on mechanical and metallurgical properties during DFSW. Unlike conventional fusion welding methods that are accompanied with substantially thick interfacial IMCs, forming an interfacial metallurgical bond during DFSW is essential to achieve a sound joint. However, it should be kept at optimum condition to enhance and improve mechanical properties i.e. it should be thin, uniform and contentious.\nIMCs.\nIMCs are another typical phenomenon in DFSW. There existed some criteria for IMCs in order to achieve a sound joint including thickness, uniformity and continuity. The most common type of IMCs appeared in aluminum/copper joint are Al4Cu9, Al2Cu3, Al2Cu. Interface and surrounding edge of the particles dispersed in the nugget zone are two main places IMCs formed. Likewise, depending the size of the particles of harder material which dispersed in the matrix of softer material, coarse particles partially transform to IMCs mostly around the outer edge of the particles, while fine particles completely transform to IMCs. It is worth noting that the average thickness of IMCs are less than 2 micrometer. Therefore, those particles that are below than 2 micrometer are completely transform to IMCs resulting in enhancing mechanical properties of the nugget zone.\nTensile Strength.\nAnother important characteristic in DFSW is the final tensile strength. The majority of dissimilar weldments presented similar trend in tensile strength. There are two different materials in DFSW. One is softer than the other. For example, in aluminum to copper joint, aluminum is softer than copper. What would be the tensile strength of the joint? Is it more than both? Is it less than both? What is the requirement for the sound joint? The answer is that tensile strength of the joints in DFSW are a fraction of the tensile strength of the softer material. Therefore, the final tensile strength of the weldments are usually less than tensile strength of both materials, however, in order to be acceptable in the industry, it is usually more than 70 percent of the tensile strength of the softer material. Fracture behavior of the tensile specimens shows that majority of the joints failed at the interface along with a brittle fracture. It can be attributed to IMCs developed at the interface. Although, it could successfully improve tensile strength, but the specimens showed brittle fracture which is one of the existing challenge in dissimilar joints fabricated by FSW.\nFormation of composite structure.\nDue to the fact that there are two different materials in DFSW; formation of a composite structure within the nugget zone is inevitable. Typically, it appears in the forming of onion ring in the nugget zone or stir zone of the softer matrix as shown in below figure. That is, fine particle of the material in the advancing side (harder material) disperse throughout the stir zone of the retreating material (Softer material). That is the main reason regarding the inhomogeneous hardness distribution in the stir zone.\nChallenge.\nFSW can be efficient method to be used in order to join dissimilar materials and the outcome in terms of tensile strength, shear strength, and hardness distribution are promising. However, most of the joints fractured at interface. Moreover, even those that have been ruptured in the base metals showed brittle behavior i.e. low elongation which can be attributed to formation of IMCs. There must a balance between tensile strength and ductility of the weldments in order to safely use dissimilar weldments in industrial applications. In other words, proper ductility and toughness are required for some industrial applications since they should possess proper resistivity against impact and shock loading. The majority of the fabricated weldments are not sufficiently strong to be used for such applications. Therefore, it is worthwhile to focus current and future works on improving toughness of the weldments along with keeping tensile strength in a proper value.", "Engineering,_Manufacturing": 0.9999471903, "qwen": "Yes"}
{"id": "8264048", "revid": "776137", "url": "https://en.wikipedia.org/wiki?curid=8264048", "title": "Group technology", "text": "Group technology or TZ is a manufacturing technique in which parts having similarities in geometry, manufacturing process and/or functions are manufactured in one location using a small number of machines or processes. Group technology is based on a general principle that many problems are similar and by grouping similar problems, a single solution can be found to a set of problems, thus saving time and effort.\nThe group of similar parts is known as part family and the group of machineries used to process an individual part family is known as machine cell. It is not necessary for each part of a part family to be processed by every machine of corresponding machine cell. This type of manufacturing in which a part family is produced by a machine cell is known as cellular manufacturing. \nThe manufacturing efficiencies are generally increased by employing GT because the required operations may be confined to only a small cell and thus avoiding the need for transportation of in-process parts.\nGroup technology is an approach in which similar parts are identified and grouped together in order to take advantage of the similarities in design and production. Similarities among parts permit them to be classified into part families.\nThe advantage of GT can be divided into three groups:\nDisadvantages of GT Manufacturing :", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "47444668", "revid": "1147816390", "url": "https://en.wikipedia.org/wiki?curid=47444668", "title": "Press hardening", "text": "Hot stamping (also known as press hardening, hot press forming, or hot forming die quenching) is a relatively new technology which allows ultra-high strength steels (typically 22MnB5 boron steel) to be formed into complex shapes, which is not possible with regular cold stamping operations. This process is commonly used for the production of automotive body in white components because its advantages align with the design criteria of modern passenger vehicles.\nMethods.\nThe unformed blank is heated in a furnace, formed in hot condition (state 2 in below figure), and quenched in the die to achieve the required properties.\nThe blank is formed, trimmed, and pierced in cold condition (i.e., state 1 in below figure). It is later heated and quenched in a die to get high strength properties.\nSelection of the process depends on part complexity and blank coating (Zn based coatings typically require indirect process). In either method, the blank is formed in a much softer and formable state and is later hardened in the dies, which have drilled cooling channels. A typical hot stamped components has 1000 MPa (145 ksi) Yield Stress and 1500 MPa (215 ksi) Ultimate tensile strength.\nAdvantages.\nHigher strength steels may help reducing the weight by downgaging (i.e., use of thinner sheets), while increasing the crashworthiness. However, one problem with many high strength steels is that their formability is generally lower than milder grades. In addition, springback and die wear also cause problems as the forming stresses and contact pressures are higher.", "Engineering,_Manufacturing": 0.9997554421, "qwen": "Yes"}
{"id": "47446083", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=47446083", "title": "Economies of density", "text": "In microeconomics, economies of density are cost savings resulting from spatial proximity of suppliers or providers. Typically higher population densities allow synergies in service provision leading to lower unit costs. If large economies of density exist there is an incentive for firms to concentrate and agglomerate.\nTypical examples are found in logistic systems where the distribution or collection of goods is needed, such as solid waste management. Delivering, for instance, mail in an area with many postboxes results in overall cost savings and thus lower delivery costs. \nDifferent network infrastructures such as electricity or gas networks show as well economies of density.\nEconomies of density are not to be confused with economies of scale where unit costs are not linked to spatial properties.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "753016", "revid": "3727527", "url": "https://en.wikipedia.org/wiki?curid=753016", "title": "Substrate (printing)", "text": "Substrate is used in a converting process such as printing or coating to generally describe the base material onto which, e.g. images, will be printed. Base materials may include:\nElectronics.\nPrinting processes such as silk-screening and photolithography are used in electronics to produce printed circuit boards and integrated circuits. Some common substrates used are;", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "62280237", "revid": "6727347", "url": "https://en.wikipedia.org/wiki?curid=62280237", "title": "Electronics prototyping", "text": "In electronics, prototyping means building an actual circuit to a theoretical design to verify that it works, and to provide a physical platform for debugging it if it does not. The prototype is often constructed using techniques such as wire wrapping or using a breadboard, stripboard or perfboard, with the result being a circuit that is electrically identical to the design but not physically identical to the final product.\nOpen-source tools like Fritzing exist to document electronic prototypes (especially the breadboard-based ones) and move toward physical production. Prototyping platforms such as Arduino also simplify the task of programming and interacting with a microcontroller. The developer can choose to deploy their invention as-is using the prototyping platform, or replace it with only the microcontroller chip and the circuitry that is relevant to their product.\nA technician can quickly build a prototype (and make additions and modifications) using these techniques, but for volume production it is much faster and usually cheaper to mass-produce custom printed circuit boards than to produce these other kinds of prototype boards. The proliferation of quick-turn PCB fabrication and assembly companies has enabled the concepts of rapid prototyping to be applied to electronic circuit design. It is now possible, even with the smallest passive components and largest fine-pitch packages, to have boards fabricated, assembled, and even tested in a matter of days.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "62302975", "revid": "12416903", "url": "https://en.wikipedia.org/wiki?curid=62302975", "title": "Soft Growing Robotics", "text": "Soft Growing Robotics is a subset of soft robotics concerned with designing and building robots that use robot body expansion to move and interact with the environment.\nSoft growing robots are built from compliant materials and attempt to mimic how vines, plant shoots, and other organisms reach new locations through growth. While other forms of robots use locomotion to achieve their objectives, soft growing robots elongate their body through addition of new material, or expansion of material. This gives them the ability to travel through constricted areas and form a wide range of useful 3-D formations. Currently there are two main soft growing robot designs: additive manufacturing and tip extension. Some goals of soft growing robotics development are the creation of robots that can explore constricted areas and improve surgical procedures.\nAdditive manufacturing design.\nOne way of extending the robot body is through additive manufacturing. Additive manufacturing generally refers to 3-D printing, or the fabrication of three dimensional objects through the conjoining of many layers of material. Additive manufacturing design of a soft growing robot utilizes a modified 3-D printer at the tip of the robot to deposit thermoplastics (material that is rigid when cooled and flexible when heated) to extend the robot in the desired orientation.\nDesign characteristics.\nThe body of the robot consists of:\nThe additive manufacturing process involves polylactic acid filament (a thermoplastic) being pulled through the tubular body of the robot by a motor in the tip. At the tip, the filament passes through a heating element, making it pliable. The filament is then turned perpendicular to the direction of robot growth and deposited onto the outer edge of a rotating disk facing the base of the robot. As the disk (known as the deposition head) rotates, new filament is deposited in spiraling layers. This filament solidifies in front of the previous layer of filament, pushing the tip of the robot forward. The interactions between the temperature of the heating element, the rotation of the deposition head, and the speed the filament is fed through the heating element is precisely controlled to ensure the robot grows in the desired manner.\nMovement control.\nThe speed of the robot is controlled by changing the temperature of the heating element, the speed at which filament is fed through the heating element, and the speed the deposition head is spun. Speed can be defined as the function:\nformula_1\nWhere formula_2 is the thickness of the deposited layer of filament, and formula_3 is the angle of the helix in which the filament material is deposited.\nControlling the direction of growth (and thus the direction of robot \"movement\") can be done in two ways:\nCapabilities.\nOne of the major advantages of soft growing robots is that minimal friction exists between the outside environment and the robot. This is because only the robot tip moves relative to the environment. Multiple robots using additive manufacturing for growth were designed for burrowing into the soil, as less friction with the environment reduces energy required to move through the environment\nTip extension design.\nA second form of soft growing robot design is tip extension. This design is characterized by a tube of material (common materials include nylon fabric, low density polyethylene, and silicone coated nylon) pressurized with air or water that is folded into itself. By letting out the folded material, the robot extends from the tip as the pressurized tube pushes out the inner folded material.\nDesign characteristics.\nIn contrast with additive manufacturing where new material is deposited behind the tip of the robot to push the tip forward, tip extension utilizes the internal pressure within the robot body to push out new material at the tip of the robot. Often, the tubing inside the robot body is stored on a reel to make it easier to control the release of tubing and thus robot growth.\nMultiple methods of turning a tip extension robot have been developed. They include:\nRobots utilizing the tip extension design are retractable. Current designs use a wire attached to the tip of the robot that is used to pull the tip of the robot back into the robot body.\nMathematical analysis.\nThe theoretical force the tip grows under can be modelled as:\nformula_4\nWhere formula_5 represents the force the tip grows under, formula_6 represents internal pressure, and formula_7 represents cross sectional area of the robot tip. However, the experimental force the tip expands under has been found to be less than this largely due to axial tension in the robot body. A model that approximates formula_5 more accurately is:\nformula_9\nHere, formula_10 is an experimentally determined constant and formula_11 is yield pressure when no growth occurs. formula_12, formula_13, and formula_14, are force terms dependent on velocity, length, and curvature or the robot respectively.\nAdditionally, multiple mathematical models for various forms of turning, twisting, and retracting have been developed.\nMethods of robot operation.\nSoft growing robots can be controlled in various ways depending on how well the objective and growth path are defined. Without a clearly defined goal or robot growth path, teleoperation is used. When a clearly defined goal exists (such as a light source), computer vision can be used to find a path to the goal and grow a robot along that path. If the desired path of robot growth is known before the robot is deployed, pre-planned turning positions can be used to control the robot.\nApplications.\nPossible applications of soft growing robots focus on their low friction/interaction with the environment, their simple method of growth, and their ability to grow through cramped environments.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "62313405", "revid": "46314663", "url": "https://en.wikipedia.org/wiki?curid=62313405", "title": "Microstructures in 3D printing", "text": "The use of microstructures in 3D printing, where the thickness of each strut scale of tens of microns ranges from 0.2mm to 0.5mm, has the capabilities necessary to change the physical properties of objects (metamaterials) such as: elasticity, resistance, and hardness. In other words, these capabilities allow physical objects to become lighter or more flexible. The pattern has to adhere to geometric constraints (shape regulations), and thickness constraints (minimum thickness control), or can be enforced using optimization methods (microstructure shape and topological optimization). Innovations in this field are being discovered in addition to 3D printers being built and researched with the intent to specialize in building structures needing altered physical properties.\nMicrostructure parameters.\nElastic deformation materials are described by two major parameters: Poisson's ratio and Young's modulus. However, the alternative elastic constants, Bulk modulus and Shear modulus can also be used. Poisson's ratio defines the ratio between the transversal and axial strain when the object is compressed. Materials with negative Poisson's ratio expand laterally when stretched, in contrast with ordinary materials. In comparing a material's resistance to distort under mechanical load rather than a change in volume, Poisson's ratio offers the fundamental metric by which to compare the performance of any material when strained elastically. The numerical limits are set by 1/2 and -1, between which all stable isotropic materials are found. Young's modulus is a property that measures how rigid or soft an object is. It relates stress (per unit area) to strain (proportional deformation) along an axis or line.\nMicrostructure process chain.\nThe microstructures are designed synthetically, given the input parameters correlated with the desired deformation behavior. Parameters space sampling allows the creation of a family of related structures able to satisfy the feasibility range of material parameters. The corresponding microstructure of the cell is computed by interpolation. Using microstructure optimization and parameter space sampling, several families of related structures that together satisfy the feasible range of material parameters can be defined. Using these candidates, the best fit is chosen to ensure that neighboring structures are properly connected.\nSteps for additive manufacturing.\nAdditive manufacturing design can be divided into two general steps: the pre-processing planning and the process chain. During the pre-processing planning a microstructure design (3D geometric modelling by the use of CAD modelling system) and properties are modelled (factors and parameters).\nThe process chain of additive manufacturing can be synthesized in the following five steps:\nDepending on the quality of the model and results of steps 3 through 5 respectively, the process may be iterated until a satisfactory model or part is achieved.\nMicrostructures optimization.\nPattern optimization.\nTo create a microstructure, first, a kind of tile has to be designed which provides isotropy, for example, a cube. By assigning nodes to the vertices, the edges, the surfaces, and one node to the interior of the shape of the tile, it is possible to connect these nodes. These connections are the parts which will be printed, and the choice of which nodes will be connected with other nodes determines the properties and stability of the microstructure. Therefore, maximizing the edge space and the vertex space is important to achieve an optimized microstructure. However, the following two attributes have to be met to be able to print the structure:\nPrintability.\nPrintability can be achieved by ensuring that for every set of connected nodes on one level, there is at least one node which is connected to another node located lower in the structure. This criterion obviously does not have to be met for the lowest level. In addition to that, the edges between the nodes have to be sufficiently thick.\nTileability.\nIn order to be connectable, the set of nodes which are on the surface of the tile must be the same on every side. This means if two tiles are put together, the respective nodes must connect. The actual microstructure consists of these tiles which are connected through the nodes on the tile-surface.\nShape optimization.\nGeometry complexity in 3D printing requires the control of the material parameters and therefore their properties to produce microstructures which can achieve different behaviors. Shape optimization can perfectly improve stress concentration. Based on the assumption that curvature variation and negatively curved regions generated high stress regions, introduces a low dimensional parametric shape model to eliminate sharp concave corners, which supports minimization of maximal stress and an efficient implementation of printability constraint. Shape optimization is based on the thickness of the deposited material to reduce the stress concentration by first accurately representing shells in the shape of conic by the use of the CAD, and then derived by sensitivity analysis the stress required.\nTopology optimization.\nBendsøe and Kikuchi can be considered as the pioneers in the microstructure topology optimization domain, which was originally intended for the design of mechanical structures. In additive manufacturing, topology optimization is considered an efficient method to find the right topologies by running optimization algorithms targeting the prescribed properties. The effective properties of the material structures are found using a numerical homogenization method, and then the topology optimization is applied to find the best distribution of material phases that extremizes the objective function. The Inverse homogenization method has been introduced to achieve specific macro-scale behaviors with desired Poisson’s ratio. The inverse homogenization method plus constraint approach has been extended to design mechanical properties. A proposed data-driven approach encodes the variability in properties into a viable finite-dimensional stochastic model with prescribed constraints and optimized to obtain the target properties. One of the problems in topology optimization is the increasing number of parameters due to the linear number of cells in the object. Two approaches have been investigated to resolve this complexity. First, working with microstructures corresponding to blocks of voxels instead of individual voxels directly. Second, ignoring the microstructure geometry and considering only the macroscopic behavior.\nPrinting methods used for microstructures.\nAdditive manufacturing is used for the realization of complex material composition in 3D printing. Different techniques can be used to create microstructures, but they need to be able to print thin and complex structures.\nMicrostructures applications.\nPossible applications of microstructures are the fabrication of plastic toys using metamaterials to give them an elastic behavior. The design of microstructures brings possibilities of realizing novel properties beyond traditional materials, and the use in different domains such as mechanical engineering, aeronautics, astronomy, and electronics, based on their deformation, compression, light, sound, thermal and mechanical properties. In the medical domain, applications have been demonstrated with the ability to synthesize tissue, or to fabricate prosthetics or manufacturing bone with biomaterial. Other examples of applications of microstructures are the creation of sound absorbing material, using them as a catalyst, to create custom structures or just for design purposes.", "Engineering,_Manufacturing": 1.0000072718, "qwen": "Yes"}
{"id": "5999177", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=5999177", "title": "RAVON", "text": "RAVON (Robust Autonomous Vehicle for Off-road Navigation) is a robot being developed at the Robotics Research Lab at University of Kaiserslautern, Germany. The vehicle is used as a testbed to investigate behaviour-based strategies on motion adaptation, localization and navigation in rough outdoor terrain. The basis vehicle was produced by Robosoft.\nDescription.\nThe vehicle uses a 3D laser scanner.\nThe vehicle is an example of using behavior-based components on two layers of a multi-layer control system. It also uses a form of short-term memory to prevent collisions with obstacles that it observed some time ago.\nThe vehicle was experimentally tested at the 2nd Military European Land Robot Trial 2008.", "Engineering,_Manufacturing": 0.9999428988, "qwen": "Yes"}
{"id": "24387025", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=24387025", "title": "Pullapart", "text": "PullApart was a UK-based, independent packaging recycling classification system. Applied at the kerbside, it combined environmental and consumer packaging surveys to provide customers with a measurement of the ease with which specific types of packaging could be locally recycled. The process was invented by Michael Butler of Dawlish in 2005, and operated for free.\nMethodology.\nAs PullApart was applied to existing local authority-installed recycling bin refuse collection systems, its scoring scheme was dependent on individual local authorities’ own packaging disassembly practices. Sample packaging was disassembled, according to the Local Authority’s process, rearranged and its components graded for ease of recycling. The raw information from this exercise was also made available to the public.\nA final, consumer-oriented \"PAC\" (PullApart Code) score was achieved by measuring what proportion of a product's components was recyclable from the kerbside. The PAC score is represented by 13 stages of ‘traffic light’ grading.\nBroader aims.\nPullApart’s stated aims are to encourage, manufactures, retailers, food and agricultural producers to give greater weight to the ease of disposal and recycling in their packaging designs. Weighting the consumers point of view equally to that of packaging manufactures, retailers and recyclers, in the handling of domestic waste products for kerbside collections. To provide consumers with information enabling product choice (ethical consumerism), that's easy, local and totally kerbside recyclable. Furnishing an unambiguous tool, that measures the differences between those mentioned above, assisting in the optimisation of products for the goal of near Zero waste.\nAccording to PullApart’s then current Teignbridge (2011) survey of over 2000 products, 2.84% were ideally suited for kerbside recycling and a further 29.32% were good, whilst the rest failed. The sample area, Teignbridge, and therefore Teignbridge District Council, had a current recycling rate of 57% (2008/2009), (by weight). Quoting from their periodical, “Teignbridge Life” explaining to local people how PullApart worked: “The online packaging recycling guide features a free search function which classifies ordinary consumer products, like cereal boxes, with a 'PullApart' rating. The rating breaks the product down into its components, explaining which parts can be recycled in Teignbridge.”\nAwards for the scheme.\nPullApart is considered to be of “Environmental Best Practice” by The Green Organisation.\nComparison with other efforts.\nWorldwide there are broader packaging scoring systems that address the full environmental impact of packaging. Recycling being one factor, other vital considerations include the use of recycled materials in the package, avoidance of toxic substances, minimization of packaging, effects on atmosphere (greenhouse gas, VOC, etc.), use of renewable resources, etc. Efforts involve methodologies such as life cycle assessment to inventory the all environmental impacts and factors.\nThere are many Sustainability metrics and indices, some specifically for packaging.", "Engineering,_Manufacturing": 0.9861993194, "qwen": "Yes"}
{"id": "311563", "revid": "43148149", "url": "https://en.wikipedia.org/wiki?curid=311563", "title": "Lockout chip", "text": "In a general sense, a lockout chip is a chip within an electronic device to prevent other manufacturers from using a company's device to perform certain functions.\nA notable example is the lockout chip found in Nintendo's Nintendo Entertainment System (called 10NES), designed to prevent \"unlicensed\" manufacturers from creating games for the console. The presence of the chip forced unlicensed companies to raise the price of each cartridge (due to a bypass chip having to be added to the cartridge), and allowed Nintendo a foothold for a lawsuit.\nLockout functions are commonly used in printers to prevent the manufacture of third-party ink or toner cartridges.", "Engineering,_Manufacturing": 0.987125814, "qwen": "Yes"}
{"id": "311682", "revid": "35227944", "url": "https://en.wikipedia.org/wiki?curid=311682", "title": "Machinist", "text": "A machinist is a tradesperson or trained professional who operates machine tools, and has the ability to set up tools such as milling machines, grinders, lathes, and drilling machines.\nA competent machinist should have a well-developed mechanical aptitude, the ability to correctly use precision measuring instruments, interpret blueprints, and a working knowledge of the proper parameters required for successfully utilizing the various tools commonly used in machining operations.\nNature of work.\nThe machine trade is an extremely broad field with a wide variety of workplaces, job duties, and types of work. Most Machinists work in machine shops and factories where they operate machinery that produce precision component parts. In general, the occupation is exacting, and requires extensive knowledge of the tools and processes in order to achieve the tight tolerances and surface finishes that these parts specify. \nMany machinists make Mass-produced parts using highly automated computer numerical control machines which are common today, but still require such professionals to set up and calibrate the machines. Other more specialized machinists produce custom-made parts for prototyping, repair, or research. A machinist may work on manufacturing something relatively simple like a bracket, or a shaft, or something extraordinarily complex, such as aerospace components accurate to .0002 of an inch.\nGood machinists are highly sought after and respected skilled trades persons and are generally well-paid. In utility, medical, and military use companies, experienced machinists can earn over $100,000 per year.\nRelated occupational titles.\nSome titles reflect further development of machinist skills such as tool and die maker, patternmaker, mold maker, programmer, and operator. A machinist is one who is called on to fix a problem with a part or to create a new one using metals, plastics, or rarely, wood. Depending on the company, a machinist can be any or all of the titles listed above.\nother related fields include Millwrights, quality assurance, and mechanical engineers. \nIn Australia, a related profession is a fitter and turner. A fitter and turner is the tradesperson who fits, assembles, grinds and shapes metal parts and subassemblies to fabricate production machines and other equipment.\nUnder the machinist title are other specialty titles that refer to specific skills that may be more highly developed to meet the needs of a particular job position, such as fitter (assembles parts), turning hand, mill hand, and grinder.\nRole in manufacturing.\nA machinist is usually called upon when a part needs to be produced from a stock material by cutting. Such a part may be unique or may be needed in the thousands. The part could be anything made from metal or plastic, though machined parts are usually ones that require high precision and cannot be produced by other means. Machinists generally start with a saw cut length of stock or a casting. Producing a part will often require several steps and more than one machine tool. Each machine tool plays a specific role in cutting away excess material. When large numbers of parts are needed, production planning is required to plan the most logical workflow through a series of machines. Computer numerical controlled (CNC) machines are computer-driven tools that can machine a large variety of shapes, and whose use in the workflow depends on the part to be machined.\nCNC machines are becoming the standard due to their speed, precision, flexibility, repeatability, and reduced downtime while changing jobs. Production runs consisting of large numbers of parts are more cost effective and commonly referred to as production work in the trade. Conversely, small production runs are sometimes referred to as prototype or jobbing work.\nProduction engineers use blueprints and engineering drawings to produce detailed specifications of the part, especially its geometry (shape), then decide on a strategy to make it. Machine tools are then configured by the machinist and production commences. The machinist works with the quality department to ensure the specifications are maintained in the finished product.\nLarge commercial organizations often staff machinists on site in a maintenance mode to ensure continuing operations of the production machinery. Such machinists can often make replacement parts the same day. Because of this, the labor cost for this role are significantly lower than costs involved with production shutdowns.\nAdditive machining.\nAdditive machining means 3D printing to create industrial components, prototypes, tooling, and end-use production parts. Additive machining comes into its own in the manufacturing of very small intricate parts, which could not be produced through any other manufacturing process. There are several processes in additive manufacturing which include direct metal deposition: electron beam melting, fused filament fabrication, select laser sintering, and variations of them.\nMaterials commonly encountered by machinists.\nThe most common materials that machinists make parts from are steel, aluminium, brass, copper, and various alloys of these materials. Other less common materials such as vanadium, zinc, lead, or manganese are often used as alloying elements for the most common materials. Materials that machinists work with occasionally are plastics, rubber, glass, and wood products. Rarely, machinists also work with exotic and refractory metals. The term exotic metals is a general term describing out of the ordinary, rare or special purpose metals. A synonym might be space-age. A list of exotic metals might include, but is not limited to, titanium, beryllium, vanadium, chromium, molybdenum and tungsten, as well as special high-temperature metal alloys like Inconel or Hastelloy (superalloys). Very often the meaning of the term suggests the need for specialized handling and/or tooling to machine them effectively.\nWhile the foregoing were primarily the materials that a machinist would be cutting, the cutters that the machinist uses must be harder and tougher than the materials to be cut. The materials in the cutters a machinist uses are most commonly high-speed steel, tungsten carbide, ceramics, Borazon, and diamond.\nMachinists usually work to very small tolerances, usually within 0.010\" or 0.25 mm (more commonly expressed as ±0.005\" (Plus or minus five thousandths of an inch) or ±0.13 mm), and sometimes at tolerances as low as +/-0.0001\" (plus or minus one tenth of a thousandth of an inch – or 0.0025 mm) for specialty operations. A machinist deals with all facets of shaping, cutting and some aspects of forming metal, although forming is typically a separate trade. The operations most commonly performed by machinists are milling, drilling, turning, and grinding. There are other more specialized operations that a machinist will less frequently be called upon to perform such as honing, keyseating, lapping, and polishing, to name a few.\nTools of the machinist.\nThe tools that a machinist is expected to be proficient with fall into broad categories:", "Engineering,_Manufacturing": 1.0000007153, "qwen": "Yes"}
{"id": "313190", "revid": "46237007", "url": "https://en.wikipedia.org/wiki?curid=313190", "title": "Preventive maintenance checks and services", "text": "Preventive maintenance checks and services (PMCS) in the United States Army or preventive maintenance inspections (PMI) in the United States Air Force are the checks, services, and maintenance performed before, during, and after any type of movement or before the use of all types of military equipment.\nDescription.\nMost pieces of military equipment have PMCS charts used to go over every detail needed or noted to ensure the proper function of every mechanical item or non-mechanical surface. A PMCS check is required before, during, and after a piece of equipment or vehicle is used. Checks are also done at weekly, monthly, semi-annual, annual, or bi-annual intervals, depending on the specific part.\nDoing a PMCS check every time equipment is used may reduce the number of failures. This reduces the number of injuries during training exercises, improve effectiveness in combat, and increase the operator's ability to implement their equipment.\nA PMCS is required before a vehicle can be dispatched and before a piece of equipment, such as a weapon, can be issued. A PMCS sheet, as listed above, for vehicles is called a DA 5988E. This sheet is used to write down any deficiency found during the PMCS procedure. The steps taken to perform the PMCS are explained in a Technical Manual and performed by the operator. A PMCS is also used at the unit level.", "Engineering,_Manufacturing": 0.9999736547, "qwen": "Yes"}
{"id": "2651194", "revid": "13286072", "url": "https://en.wikipedia.org/wiki?curid=2651194", "title": "Angle plate", "text": "An angle plate is a work holding device used as a fixture in metalworking.\nAngle plates are used to hold workpieces square to the table during marking out operations. Adjustable angle plates are also available for workpieces that need to be inclined, usually towards a milling cutter. Angle plates are made from high quality material (generally spheroidal cast iron) that has been stabilized to prevent further movement or distortion. Slotted holes or \"T\" bolt slots are machined into the surfaces to enable the secure attachment or clamping of workpieces to the plate, and the plate to the worktable. ", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "2651355", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=2651355", "title": "Indexing head", "text": "An indexing head, also known as a dividing head or spiral head, is a specialized tool that allows a workpiece to be circularly indexed; that is, easily and precisely rotated to preset angles or circular divisions. Indexing heads are usually used on the tables of milling machines, but may be used on many other machine tools including drill presses, grinders, and boring machines. Common jobs for a dividing head include machining the flutes of a milling cutter, cutting the teeth of a gear, milling curved slots, or drilling a bolt hole circle around the circumference of a part.\nThe tool is similar to a rotary table except that it is designed to be tilted as well as rotated and often allows positive locking at finer gradations of rotation, including through differential indexing. Most adjustable designs allow the head to be tilted from 10° below horizontal to 90° vertical, at which point the head is parallel with the machine table.\nThe workpiece is held in the indexing head in the same manner as a metalworking lathe. This is most commonly a chuck but can include a collet fitted directly into the spindle on the indexing head, faceplate, or between centers. If the part is long then it may be supported with the help of an accompanying tailstock.\nManual indexing heads.\nIndexing is an operation of dividing a periphery of a cylindrical workpiece into equal number of divisions by the help of index crank and index plate.\nA manual indexing head includes a hand crank. Rotating the hand crank in turn rotates the spindle and therefore the workpiece. The hand crank uses a worm gear drive to provide precise control of the rotation of the work. The work may be rotated and then locked into place before the cutter is applied, or it may be rotated during cutting depending on the type of machining being done.\nMost dividing heads operate at a 40:1 ratio; that is 40 turns of the hand crank generates 1 revolution of the spindle or workpiece. In other words, 1 turn of the hand crank rotates the spindle by 9 degrees. Because the operator of the machine may want to rotate the part to an arbitrary angle indexing plates are used to ensure the part is accurately positioned.\nDirect indexing plate: Most dividing heads have an indexing plate permanently attached to the spindle. This plate is located at the end of the spindle, very close to where the work would be mounted. It is fixed to the spindle and rotates with it. This plate is usually equipped with a series of holes that enables rapid indexing to common angles, such as 30, 45, or 90 degrees. A pin in the base of the dividing head can be extended into the direct indexing plate to lock the head quickly into one of these angles. The advantage of the direct indexing plate is that it is fast and simple and no calculations are required to use it. The disadvantage is that it can only be used for a limited number of angles.\nInterchangeable indexing plates are used when the work must be rotated to an angle not available on the direct indexing plate. Because the hand crank is fixed to the spindle at a known ratio (commonly 40:1) the dividing plates mounted at the handwheel can be used to create finer divisions for precise orientation at irregular angles. These dividing plates are provided in sets of several plates. Each plate has rings of holes with different divisions. For example, an indexing plate might have three rows of holes with 24, 30, and 36 holes in each row. A pin on the hand crank engages these holes. Index plates with up to 400 holes are available. Only one such plate can be mounted to the dividing head at a time. The plate is selected by the machinist based on exactly what angle he wishes to index to.\nFor example, if a machinist wanted to index (rotate) his workpiece by 22.5 degrees then he would turn the hand crank two full revolutions plus one-half of a turn. Since each full revolution is 9 degrees and a half-revolution is 4.5 degrees, the total is 22.5 (9 + 9 + 4.5 = 22.5). The one-half turn can easily be done precisely using any indexing plate with an even number of holes and rotating to the halfway point (Hole #8 on the 16-hole ring).\nBrown and Sharpe indexing heads include a set of 3 indexing plates. The plates are marked #1, #2 and #3, or \"A\", \"B\" and \"C\". Each plate contains 6 rows of holes. Plate #1 or \"A\" has 15, 16, 17, 18, 19, and 20 holes. Plate #2 or \"B\" has 21, 23, 27, 29, 31, and 33 holes. Plate #3 or \"C\" has 37, 39, 41, 43, 47, and 49 holes.\nUniversal Dividing heads: some manual indexing heads are equipped with a power drive provision. This allows the rotation of the dividing head to be connected to the table feed of the milling machine instead of using a hand crank. A set of change gears is provided to select the ratio between the table feed and rotation. This setup allows the machining of spiral or helical features such as spiral gears, worms, or screw type parts because the part is simultaneously rotated at the same time it is moved in the horizontal direction. This setup is called a \"PTO dividing head\".\nCNC indexing heads.\nCNC indexing heads are similar in design to the manual variety except that they have a servo motor coupled to the spindle instead of a hand crank and indexing plates. The servo motor is electronically controlled to index the work to the required position. The control can either be a simple keypad for the operator or it may be fully CNC controlled.\nCNC indexing heads may be controlled in two different modes. The most basic method of operation uses simple control functions built into the dividing head. It does not require a CNC machine. The operator enters the desired angle into a control box attached to the indexing head and it automatically rotates to the desired position and locks into place for machining. Changing angles is as simple as typing a new angle value onto the control pad. This is simpler than setting up a manual indexing head because there is no need to interchange indexing plates or to calculate which hole positions to use. It is also faster for repetitive operations because the work can be indexed by simply pressing a button, eliminating the need to count rotations of the hand crank or specific hole positions on the indexing plate. A CNC dividing head may be used in this manner on either manual or CNC machinery.\nMost CNC dividing heads are also able to function as a full CNC axis and may be wired into the control of a CNC machine. This enables the machine's main CNC controller to control the indexing head just like it would control the other axes of the machine. This can be used to machine complex 3D shapes, helices with a non-constant pitch, and similar exotic parts. This mode of operation cannot be used on a manual machine tool because it requires a full CNC controller to operate.", "Engineering,_Manufacturing": 0.9999644756, "qwen": "Yes"}
{"id": "46883026", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=46883026", "title": "Reverse logistics network modelling", "text": "Reverse logistics is for all operations related to the reuse of products and materials. It is \"the process of moving goods from their typical final destination for the purpose of capturing value, or proper disposal. Remanufacturing and refurbishing activities also may be included in the definition of reverse logistics.\"\nIn order to model reverse logistics network from an economics point of view, the following simplified reverse logistics system has to be set.\nIn this model the products are gathered from the consumers and transferred back to the producers, hence the direction of the flow in the distribution supply chain is reversed and the model is expanded with the recovery center. First of all the used products are collected from the consumers and moved to the recovery center, where the condition of the products are examined according to their end of life cycle. If there is still recapture value, then the product is disassembled as preparation for further reprocessing, which means physical transformation to new customer. Otherwise the used product is disposed and transferred to the landfill site. According to the introduced model the main differences between forward and reverse logistics can be identified: \nModeling techniques for optimizing in reverse logistics network.\nIn case of a reverse logistics network the nodes represent the different kind of facilities such as the manufacturers, distribution centers, recovery centers, ware houses. The opening of a facility is marked with a binary integer number. The links are acted for flow between facilities and the weights are continuous variables showing the quantity of flow. The two common way of designing reverse logistics network are the Mixed Integer Linear Programing (MILP) and Mixed Integer Non-Linear Programing (MINLP) methods, where the objective function, decision variables and constraint have to be defined\nMixed Integer Linear Programing (MILP).\nRemanufacturing model.\nThis model is a two-level location problem with three type of facilities, integrated forward and reverse flow of goods. It means that the used items are gathered from consumers, transported back to plants and after remanufacturing get into the logistics network of new products.\nObjective function: \nDecision variables: \nConstraints: \nRefurbishment model.\nThis model take into account just reverse flow of goods.\nObjective function: \nDecision variables: \nConstraints: \nGeneric reverse logistics network model.\nObjective function: \nDecision variables: \nConstraints:\nThis model can be further developed by introducing penalty cost for not collecting returned items and a compulsory minimal disposal fraction as a feasibility technical constraints of reuse. Moreover, the static approach can be partly eliminated by multi-period programming, as a result trade-off between investment and operational cost and long run effect can be analyzed.\nMixed Integer Non-Linear Programing (MINLP).\nThe most severe drawback of MILP is the static aspect, hence MINLP try to relieve these restriction and develop further the existing model with dynamic elements, such as integrating cycle time, time and inventory positions. By this way uncertainty appears stronger in the model. The main objective is to maximize profit by determining the optimal number of facilities in order to:\nSolution techniques of reverse logistics network models.\nGenetic algorithm.\nIt is applicable for large size complex problems\nMain steps of the algorithm: \nTabu search.\nThe algorithm pursues local search and if it finds a local optimum it is prevented to get back formerly visited solution, which were recorded in the so-called tabu list", "Engineering,_Manufacturing": 0.9999595881, "qwen": "Yes"}
{"id": "46887899", "revid": "45780481", "url": "https://en.wikipedia.org/wiki?curid=46887899", "title": "RePack", "text": "RePack is a packaging service which enables the return and reuse of delivery packaging for online retailers and their users. The service and packaging is designed by Original RePack Oy, a Finnish company focused on sustainable products and business model solutions.\nBusiness.\nOn supported e-commerce sites, the customer can select to use RePack as the online order's delivery packaging. The customer will then receive the goods in RePack's recyclable packaging. This packaging can be returned to RePack by dropping it into a local letterbox, and can be reused up to 20 times.\nThe return rate of RePack's products has reached 95%.\nRePack is used by over 200 online retailers in Europe and the US.\nAwards.\nIn October 2013, RePack was awarded the Pactec 2013 innovation prize by the Finnish packaging association.\nIn January 2014, RePack was awarded the Fennia Prize.\nIn September 2014, RePack won the Green Alley startup competition in Germany.\nIn November 2014, RePack finished fourth in Slush 100’s pitching competition for startups.\nIn November 2017, the company was awarded the Nordic Council Environment Prize.", "Engineering,_Manufacturing": 0.9996209741, "qwen": "Yes"}
{"id": "47629344", "revid": "45170226", "url": "https://en.wikipedia.org/wiki?curid=47629344", "title": "Exchange spring media", "text": "Exchange spring media (also exchange coupled composite media or ECC) is a magnetic storage technology for hard disk drives that allows to increase the storage density in magnetic recording. The idea, proposed in 2004 by Suess et al., is that the recording media consists of exchange coupled soft and hard magnetic layers. Exchange spring media allows a good writeability due to the write-assist nature of the soft layer. Hence, hard magnetic layers such as FePt, CoCrPt-alloys or hard magnetic multilayer structures can be written with conventional write heads. Due to the high anisotropy these grains are thermally stable even for small grain sizes. Small grain sizes are required for high density recording. The introduction of the soft layer does not decrease the thermal stability of the entire structure if the hard layer is sufficiently thick. The required thickness of the hard layer for best thermal stability is the exchange length of the hard layer material.\nThe first experimental realization of exchange spring media was done on Co-PdSiO multilayers as the hard layer which was coupled via a PdSi interlayer to a FeSiO soft layer.\nBesides the improved writeability, another advantage of exchange spring media is, that the switching field distribution of the grains, which has to be as small as possible to allow for high storage densities, can be decreased. This effect was predicted theoretically and experimentally verified on Co/Pd multilayers as hard layer coupled to Co/Ni multilayers as soft layer.\nIn commercial hard disks exchange spring media is used since about 2007.", "Engineering,_Manufacturing": 0.9999427795, "qwen": "Yes"}
{"id": "42154868", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=42154868", "title": "BTU International", "text": "BTU International, Inc. was set up in 1950 and now is based in North Billerica, Massachusetts. The company focuses on thermal processing equipment for alternative energy and electronics, such as semiconductor packaging, solar cell manufacturing, printed circuit board assembly, and nuclear fuel processing. The Company completes its assembly, systems integration and testing at the facilities in North Billerica, Massachusetts and Shanghai, China.\nHistory.\nBTU International, Inc. was founded in 1950 in Cambridge, Massachusetts, producing small ovens for hospital, laboratory and daily use. The company entered the semiconductor market making alloying furnaces in late 1950s. In 1972, BTU moved to Billerica, Massachusetts. The company entered photovoltaics market and shipped its first furnace for solar cells in 1985. In 1989, BTU became a publicly traded company on the NASDAQ. In the early 1990s, BTU began to produce solder reflow related products and convections. It also produced the industry's first lead-free reflow furnace. In 1995, BTU hired its first direct employees in mainland China. The Intellectual Property portfolio of BTU includes over 200 patents and patent applications. In 2003, the Company acquired Sagarus Robotics Corporation of Tempe, Ariz, a provider of advanced, automated systems for the semiconductor packaging, MEMS and sensor markets. In 2006, BTU acquired AtmoPlas Technology and research team from Data Corporation. In the same year the company acquired the product line, trademarks and other related assets of Radiant Technology Corporation (RTC).\nProducts and services.\nIn the alternative energy market, BTU offers processing equipment for silicon and thin film photovoltaics, MERIDIAN In-line Diffusion system, spray-coating systems, rapid thermal processing furnaces (supported by near infrared heating technology), and walking beam and pusher systems for sintering nuclear fuel. \nIn the electronics market, the Company's products are used in solder reflow and curing stages for surface mount applications, such as connecting and sealing integrated circuits in wafer and dies level packaging, such as the PYRAMAX family of convection reflow systems, Flip-chip reflow.\nAwards.\nIn November 2013, BTU International, Inc. won the 2013 Global Technology Award in the category of Soldering Equipment for its new DYNAMO. The product also win the 2013 EM Asia Innovation Award during the NEPCON China event.\nIn June, 2009, BTU International won the 'Industry Choice' International Solar Technology Award.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "42167253", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=42167253", "title": "Ecomechatronics", "text": "Ecomechatronics is an engineering approach to developing and applying mechatronical technology in order to reduce the ecological impact and total cost of ownership of machines. It builds upon the integrative approach of mechatronics, but not with the aim of only improving the functionality of a machine. Mechatronics is the multidisciplinary field of science and engineering that merges mechanics, electronics, control theory, and computer science to improve and optimize product design and manufacturing. In ecomechatronics, additionally, functionality should go hand in hand with an efficient use and limited impact on resources. Machine improvements are targeted in 3 key areas: energy efficiency, performance and user comfort (noise & vibrations).\nDescription.\nAmong policy makers and manufacturing industries there is a growing awareness of the scarcity of resources and the need for sustainable development. This results in new regulations with respect to the design of machines (e.g. European Ecodesign Directive 2009/125/EC) and to a paradigm shift in the global machines market: \"instead of maximum profit from minimum capital, maximum added value must be generated from minimal resources\". Manufacturing industries increasingly require high performance machines that use resources (energy, consumables) economically in a human-centered production. Machine building companies and original equipment manufacturers are thus urged to respond to this market demand with a new generation of high performance machines with higher energy efficiency and user comfort.\nA reduction of the energy consumption lowers energy costs and reduces environmental impact. Typically more than 80% of the total-life-cycle impact of a machine is attributed to its energy consumption during the use phase. Therefore, improving a machine's energy efficiency is the most effective way of reducing its environmental impact. \nPerformance quantifies how well a machine executes its function and is typically related to productivity, precision and availability. User comfort is related to the exposure of operators and the environment to noise & vibrations due to machine operation.\nSince energy efficiency, performance and noise & vibrations are coupled in a machine they need to be addressed in an integrated way in the design phase. Example of the interrelation between the 3 key areas: with increasing machine speed typically the machine’s productivity increases, but energy consumption will increase as well and machine vibrations may grow such that machine accuracy (e.g. positioning accuracy) and availability (due to downtime and maintenance) decrease. Ecomechatronical design deals with the trade-off between these key areas.\nApproach.\nEcomechatronics impacts the way mechatronical systems and machines are being designed and implemented. Therefore, the transformation to a new generation of machines concerns knowledge institutes, original equipment manufacturers, CAE software suppliers, machine builders and industrial machine owners. The fact that about 80% of the environmental impact of a machine is determined by its design puts emphasis on making the right technological design choices. A model-based, multidisciplinary design approach is required in order to address the energy efficiency, performance and user comfort of a machine in an integrated way.\nThe key enabling technologies can be categorized in machine components, machine design methods & tools, and machine control. A few examples are listed below per category.\nMachine components\nDesign methods & tools\nMachine control\nApplications.\nSome examples of ecomechatronical system applications are:", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "42176722", "revid": "4918558", "url": "https://en.wikipedia.org/wiki?curid=42176722", "title": "Theegarten-Pactec", "text": "Theegarten-Pactec is a German manufacturer in the packaging technology sector. The company develops and produces packaging machines and complete packaging systems for bite-sized confectionery products and other foodstuffs, such as bouillon cubes, as well as for non-food items, e.g. dishwasher detergent. The packaging machines are developed and manufactured exclusively in Germany and are distributed worldwide.", "Engineering,_Manufacturing": 0.9990631938, "qwen": "Yes"}
{"id": "475255", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=475255", "title": "Logistics automation", "text": "Logistics automation is the application of computer software or automated machinery to improve the efficiency of logistics operations. Typically this refers to operations within a warehouse or distribution center, with broader tasks undertaken by supply chain engineering systems and enterprise resource planning systems.\nLogistics automation systems can powerfully complement the facilities provided by these higher level computer systems. The focus on an individual node within a wider logistics network allows systems to be highly tailored to the requirements of that node.\nComponents.\nLogistics automation systems comprise a variety of hardware and software components:\nBenefits of logistics automation.\nA typical warehouse or distribution center will receive stock of a variety of products from suppliers and store these until the receipt of orders from customers, whether individual buyers (e.g. mail order), retail branches (e.g. chain stores), or other companies (e.g. wholesalers). A logistics automation system may provide the following:\nA complete warehouse automation system can drastically reduce the workforce required to run a facility, with human input required only for a few tasks, such as picking units of product from a bulk packed case. Even here, assistance can be provided with equipment such as pick-to-light units. Smaller systems may only be required to handle part of the process. Examples include automated storage and retrieval systems, which simply use cranes to store and retrieve identified cases or pallets, typically into a high-bay storage system which would be unfeasible to access using fork-lift trucks or any other means. The use of Automatic Guided Vehicles maximizes the output compared to humans since they can do repetitive tasks for long hours and with least to no supervision. An AGV is built and programmed for precision and accuracy thereby reducing the chances of errors in a warehouse, especially when dealing with fragile goods.\nAutomation software.\nSoftware or cloud-based SaaS solutions are used for logistics automation which helps the supply chain industry in automating the workflow as well as management of the system. There are few generalized software available in the new market in the said topology. This is because there is no rule to generalize the system as well as work flow even though the practice is more or less the same. Most of the commercial companies do use one or the other of the custom solutions.\nBut there are various software solutions that are being used within the departments of logistics. There are a few departments in Logistics, namely: Conventional Department, Container Department, Warehouse, Marine Engineering, Heavy Haulage, etc.", "Engineering,_Manufacturing": 0.9991819859, "qwen": "Yes"}
{"id": "24446456", "revid": "45112151", "url": "https://en.wikipedia.org/wiki?curid=24446456", "title": "C-K theory", "text": "C-K design theory or concept-knowledge theory is both a design theory and a theory of reasoning in design. It defines design reasoning as a logic of expansion processes, \"i.e.\" a logic that organizes the generation of unknown objects. The theory builds on several traditions of design theory, including systematic design, axiomatic design, creativity theories, general and formal design theories.\nBackground.\nClaims made for C-K design theory include that it is the first design theory that:\nThe name of the theory is based on its central premises: the distinction between two spaces:\nThe process of design is defined as a \"double expansion\" of the C and K spaces through the application of four types of operators: C→C, C→K, K→C, K→K.\nThe first draft of C-K theory was sketched by Armand Hatchuel, and then developed by Hatchuel and his colleague, Benoît Weil. Recent publications explain C-K theory and its practical application in different industries.\nGenesis of C-K theory.\nC-K theory was a response to three perceived limitations of existing design theories:\nC-K theory uses an approach which is domain-independent and which allows acting on unknown objects, and changes of the definitions of known objects during the process (\"revision of objects' identities\"). C-K theory was shown by Hatchuel and Weil to be closely related to Braha's Formal Design Theory and its clarification by Braha and Reich's Coupled Design Theory, which are both based on topological structures for design modeling.\nStructure of C-K theory.\nThe core idea behind C-K theory is to define rigorously a design situation. A brief is an incomplete description of objects that do not exist yet and are still partly unknown. The first step in C-K theory is to define a brief as a concept, through the introduction of a formal distinction between concept and knowledge spaces; the second step is to characterize the operators that are needed between these two spaces.\nKnowledge.\nThe knowledge space is defined as a set of propositions with a logical status, according to the knowledge available to the designer or the group of designers. The knowledge space (i.e. K-Space) describes all objects and truths that are established from the point of view of the designer. Then K-Space is expandable as new truths may appear in it as an effect of the design process. Conversely, the structure and properties of the K-Space have a major influence on the process.\nConcept.\nA concept is defined as a proposition without a logical status in the K-Space. A central finding of C-K theory is that concepts are the necessary departure point of a design process. Without concepts, design reduces to standard optimization or problem-solving. Concepts assert the existence of an unknown object that presents some properties desired by the designer. Concepts can be partitioned or included, but not searched nor explored.\nC-K operators.\nBuilding on these premises, C-K theory shows the design process as the result of four operators: C→K, K→C, C→C, K→K.\nThe process can be synthesized through a design square. One design solution for a first concept C0 will be a path in the C-space that forms a new proposition in K. There may exist several design paths for the same C0.\nCentral findings.\nThe following graphical representation summarises the design process using C-K theory.\nCrazy concepts are concepts that seem absurd as an exploration path in a design process. Both C-K theory and practical applications have shown that crazy concepts can benefit the global design process by adding extra knowledge, not to be used to pursue that \"crazy concept\" design path, but to be used to further define a more \"sensible concept\" and lead to its eventual conjunction. The following image is a graphical representation of this process.\nThe creative aspect of Design results from two distinct expansions: C-expansions which may be seen as \"new ideas\", and K-expansions which are necessary to validate these ideas or to expand them towards successful designs.\nDomain dependent design theories are built on some specific structure of the K-space, either by assuming that some objects have invariant definitions and properties (like in all engineering fields), or by assuming that the K-space presents some stable structure (e.g. that the functions of an object can be defined independently from its technical realization, as in systematic design theory).\nAt The Design Society's 2009 International Conference on Engineering Design, an awarded-paper links scientific discovery and design process using C-K theory as a formal framework. It is suggested that a science of design is possible, and complementary to the more traditional bounded rationality.\nMathematical approaches to design have been developed since the 1960s by scholars such as Christopher Alexander, Hiroyuki Yoshikawa, Dan Braha and Yoram Reich. They tended to model the dynamic co-evolution between design solutions and requirements. Within the field of engineering design, C-K theory opens new modelling directions that explore connections with basic issues in logic and mathematics; these are different from the classic use of scientific models in design. It has been argued that C-K theory has analogies with forcing in set theory, and with intuitionistic mathematics.\nC-K theory has been applied in several industrial contexts since 1998, mainly in France, Sweden and Germany. It is generally used as a method that increases the innovative capacity of design and R&D departments. C-K theory has also inspired new management principles for collaborative innovation, with the aim of overcoming the limitations of standard design management methods.", "Engineering,_Manufacturing": 0.9880638719, "qwen": "Yes"}
{"id": "24454363", "revid": "46377538", "url": "https://en.wikipedia.org/wiki?curid=24454363", "title": "Occam process", "text": "The Occam process is a solder-free, Restriction of Hazardous Substances Directive (RoHS)-compliant method for use in the manufacturing of electronic circuit boards developed by Verdant Electronics. It combines the usual two steps of the construction of printed circuit boards (PCBs) followed by the population process of placing various leaded and non-leaded electronic components into one process. The name \"Occam\" comes from a quotation by William of Ockham.\nOverview.\nElectronic components are first positioned onto an adhesive layer of a temporary or permanent substrate, according to the design parameters. Then, the pre-tested, burned-in components are held firm in their positions by encapsulating them in insulating material, and the entire assembly is then inverted. The adhesive layer is then cut (after removing the temporary substrate if it exists) or drilled out over the component leads, mechanically or by laser ablation. These holes are then plated with a conductive, copper connection (a via) from the top of the layer to the component leads. If needed, other encapsulation layers of components or vias can be placed on top of each other to make multi-level circuit connections. This construction is then coated with copper where needed to provide traces. Thus, this finished circuit board can now receive a conformal coating to protect against the environment, and then be placed into an assembly housing or sent through another process for mechanical and/or electrical connections with other PCBs.\nAdvantages.\nIn 2006, European, RoHS regulations prompted the research needed to move from traditional lead-based solder connection processes to a more environmentally friendly approach. Much manufacturing is currently being done with tin-based solder to address this issue. Using tin requires much higher reflow temperatures and can result in rework stages due to electric shorts caused by tin-whiskers (electrically conductive structures formed in this process) and other issues in the manufacturing process which are avoided by the Occam process.\nPCBs themselves are usually created by use of a phenolic resin, itself a corrosive, toxic substance completely removed from the Occam process. Also, the nitric acid or ferric chloride used to etch traces into the boards is also removed from the process.\nSince the PCB and parts population stages happen in the same process in the same plant, a company would no longer need to wait for the delivery of ordered PCBs to begin manufacturing.\nThe high temperatures usually seen by PCBs inside of a reflow soldering oven are avoided by use of this process. This means that any issue of moisture sensitivity (MSL) in components by outgassing of moisture is completely avoided. This also then removes the storage equipment and processes needed to keep the moisture levels low in more intricate and expensive chips.\nDisadvantages.\nCurrently, though the process is set, it has not yet been implemented. It is defined as a “disruptive technology” requiring a complete change in current manufacturing processes. Therefore, cost concerns for manufacturers needing new equipment, labour concerns for current PCB manufactures and others will need to be solved or addressed before the widespread adoption of this process.\nAlthough many toxic chemicals are removed from the traditional process, Occam's increased use of encapsulation by epoxy could mean more of that sort of waste. The usual additives in epoxy have been shown to mimic estrogen, possibly resulting in adverse hormonal responses in humans.", "Engineering,_Manufacturing": 0.9999318123, "qwen": "Yes"}
{"id": "7367038", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=7367038", "title": "Vacuum packing", "text": "Vacuum packing is a method of packaging that removes air from the package prior to sealing. This method involves placing items in a plastic film package, removing air from inside and sealing the package. Shrink film is sometimes used to have a tight fit to the contents. The intent of vacuum packing is usually to remove oxygen from the container to extend the shelf life of foods and, with flexible package forms, to reduce the volume of the contents and package.\nVacuum packing reduces atmospheric oxygen, limiting the growth of aerobic bacteria or fungi, and preventing the evaporation of volatile components. It is also commonly used to store dry foods over a long period of time, such as cereals, nuts, cured meats, cheese, smoked fish, coffee, and potato chips (crisps). On a more short-term basis, vacuum packing can also be used to store fresh foods, such as vegetables, meats, and liquids, because it inhibits bacterial growth.\nVacuum packing greatly reduces the bulk of non-food items. For example, clothing and bedding can be stored in bags evacuated with a domestic vacuum cleaner or a dedicated vacuum sealer. This technique is sometimes used to compact household waste, for example where a charge is made for each full bag collected.\nVacuum packaging products, using plastic bags, canisters, bottles, or mason jars, are available for home use.\nFor delicate food items that might be crushed by the vacuum packing process (such as potato chips), an alternative is to replace the interior gas with nitrogen. This has the same effect of inhibiting deterioration due to the removal of oxygen.\nType of Vacuum Sealers or Vacuum Packaging Machines.\nEdge, Suction, and External Vacuum Sealers.\nExternal vacuum sealers involve a bag being attached to the vacuum-sealing machine externally. The machine will remove the air and seal the bag, which is all done outside the machine. A heat sealer is often used to seal the pack. Typically these units use a dry piston vacuum pump which is often considered a \"maintenance-free\" pump. If you are sealing dry goods only, this is the perfect solution. Moist foods are known to cause internal corrosion on these dry piston pumps.\nSingle Chamber Vacuum Sealers.\nSingle chamber sealers require the entire product to be placed within the machine. Like external sealers, a plastic bag is typically used for packaging. Once the product is placed in the machine, the lid is closed and air is removed. Then, there is a heat seal inside the chamber that will seal the bag, after sealing the bag the chamber is refilled with air by the automatic opening of a vent to the outside. This oncoming pressure squeezes all remaining air in the bag. The lid is then opened and the product removed. Chamber sealers are typically used for low-to-medium-volume packaging. This style of vacuum machine is also capable of sealing liquids due to equal pressure in the chamber and the bag eliminating the risk of the liquid being sucked out of the open edge of the bag.\nDouble Chamber Vacuum Sealers.\nDouble chamber sealers require the entire product to be placed in a plastic bag within the machine. Once the product is placed in the machine on the seal bar, the lid is closed and air is removed. Then a seal bar inside the chamber seals the product in the bag, after sealing the bag the chamber is refilled with air by the automatic opening of a vent to the outside. This oncoming pressure squeezes all remaining air in the bag. The lid is then opened and the product removed. Double chamber sealers are typically used for medium-volume packaging, and also have the capability to vacuum seal liquids. The lid generally swings from one side to another, increasing production speed over a single chamber model. Double chamber vacuum packaging machines generally have either spring-weighted lids or fully automatic lids.\nDouble chamber vacuum packaging machines are commonly used for:\nRotary belt type vacuum sealer (rolling vacuum sealer).\nRotary belt type vacuum packaging machine or vacuum sealer features the same function as the double chamber vacuum packaging machine as a 'vacuum bag sealer'. But the rotary belt vacuum packaging machine is more convenient, as the belt rotates automatically while the bags are placed to the sealing bar and vacuum sealing process completed. The vacuumed and sealed bags are automatically unloaded, which obviously is more convenient.\nThe packaging plate of the machine is adjustable to 4 degrees, which allows the vacuum packaging of food with soup and liquid.\nRotary belt type packaging machines are commonly used for:\nAutomatic belt vacuum chamber machines.\nAutomatic belt chamber sealers require the entire product to be placed in a plastic bag or flow wrapped pouch within the machine. The product travels on the conveyor belt, it is automatically positioned in the machine on the seal bar, the lid is closed and air is removed. Then a seal bar inside the chamber seals the product in the bag. After sealing the bag, the chamber is refilled with air by the automatic opening of a vent to the outside. This oncoming pressure squeezes all remaining air in the bag. The lid is then opened and the product removed. Automatic belt vacuum chamber machines are typically used for high-speed packaging of large items, and also have the capability to vacuum seal liquids. The lid generally travels straight up and down.\nAutomatic belt vacuum chamber packaging machines are commonly used for:\nThermoforming (rollstock) HFFS vacuum packaging machines.\nVacuum Packaging in large production facilities can be done with thermoforming machines. These are Form-Fill-Seal style machines that form the package from rolls of packaging film (webbing). Products are loaded into the thermoformed pockets, the top web is laid and sealed under a vacuum, MAP (modified atmosphere), or skin packaging producing rapidly packaged products. Thermoforming can greatly increase packaging production speed.\nThermoformed plastics can be customized for size, color, clarity, and shape to fit products perfectly, creating a consistent appearance. One of the most commonly used thermoformed plastics is PET, known for a high-strength barrier resistant to outside tampering and an ease of molding into designated designs and shapes. Some common uses for Thermoforming in vacuum packaging include:\nTypes of Food Storage.\nFood safety.\nIn an oxygen-depleted environment, anaerobic bacteria can proliferate, potentially causing food-safety issues. Some pathogens of concern in vacuum packed foods are spore-forming non-proteolytic \"Clostridium botulinum\", \"Yersenia enterocolitica\", and \"Listeria monocytogenes\". Vacuum packing is often used in combination with other food processing techniques, such as retorting or refrigeration, to inhibit the growth of anaerobic organisms.\nShelf life.\nDepending on the product, atmosphere, temperature, and the barrier properties of the package, vacuum packaging extends the shelf life of many foods. The shelf life of meats can be extended by vacuum packaging, particularly when used with modified atmosphere packaging.\nHigh Barrier - Chamber Vacuum Shrink Bags.\nThe amount of shelf life enhanced by a vacuum bag is dependent on the structure in the material. A standard vacuum bag is composed of a PA/PE structure where PA is for puncture resistance and PE is for sealing. The high barrier category includes the usage of more layers focused on the prevention of oxygen permeability, and therefore shelf life protection. There are two materials used in high barrier structures, polyvinylidene chloride (PVDC) and ethylene vinyl alcohol (EVOH). Shelf life indication can be effectively measured by how many cubic centimeters of oxygen can permeate through 1 square meter of material over a 24-hour period. A standard PA/PE bag allows on average 100 cubic centimeters, PVDC allows on average over 10, and EVOH on average 1 cubic centimeter. Multi-layer structures allow the ability to use strong oxygen-barrier materials for enhanced shelf life protection. The PremiumPack structure is a good example of EVOH based high barrier shrink material.\nEliminate freezer burn.\nWhen foods are frozen without preparation, freezer burn can occur. It happens when the surface of the food is dehydrated, and this leads to a dried and leathery appearance. Freezer burn also changes the flavor and texture of foods. Vacuum packing reduces freezer burn by preventing the food from exposure to the cold, dry air.\nTypical Uses.\nSous vide cooking.\nVacuum packaging also allows for a special cooking method, sous-vide. Sous-vide, French for \"under vacuum\", involves poaching food that is vacuum sealed in a plastic bag.\nDry Goods.\nStock up on lentils, beans, legumes, ground or whole bean coffee, rice, noodles, oatmeal, spices, cereal, powdered milk/juice, chips, potato flakes, and flour.\nVacuum Sealing Meats.\nPreserve the freshness of steak, brisket, venison, ground beef, chicken, turkey, frozen fish, moose, bear, bison, jerky, and more!\nPreservation of Vegetables.\nVacuum seal corn-on-the-cob, whole carrots, asparagus, radishes, onions, tomatoes, bell peppers, cucumbers, and other commonly used vegetables are fresh for longer.", "Engineering,_Manufacturing": 0.9991385341, "qwen": "Yes"}
{"id": "7380835", "revid": "1100792949", "url": "https://en.wikipedia.org/wiki?curid=7380835", "title": "Autonomation", "text": "Autonomation describes a feature of machine design to effect the principle of （じどうか jidouka), used in the Toyota Production System (TPS) and lean manufacturing. It may be described as \"intelligent automation\" or \"automation with a human touch\". This type of automation implements some supervisory functions rather than production functions. At Toyota, this usually means that if an abnormal situation arises, the machine stops and the worker will stop the production line. It is a quality control process that applies the following four principles:\nAutonomation aims to prevent the production of defective products, eliminate overproduction and focus attention on understanding the problems and ensuring that they do not reoccur.\nPurpose and implementation.\nShigeo Shingo calls autonomation \"pre-automation\". It separates workers from machines through mechanisms that detect production abnormalities (many machines in Toyota have these). He says there are twenty-three stages between purely manual and fully automated work. To be fully automated machines must be able to detect \"and\" correct their own operating problems which is currently not cost-effective. However, ninety percent of the benefits of full automation can be gained by Autonomation.\nThe purpose of autonomation is that it makes possible the rapid or immediate address, identification and correction of mistakes that occur in a process. Autonomation relieves the worker of the need to continuously judge whether the operation of the machine is normal; their efforts are now only engaged when there is a problem alerted by the machine. As well as making the work more interesting this is a necessary step if the worker is to be asked later to supervise several machines. The first example of this at Toyota was the auto-activated loom of Sakichi Toyoda that automatically and immediately stopped the loom if the vertical or lateral threads broke or ran out.\nFor instance rather than waiting until the end of a production line to inspect a finished product, autonomation may be employed at early steps in the process to reduce the amount of work that is added to a defective product. A worker who is self-inspecting their own work, or source-inspecting the work produced immediately before their work station is encouraged to stop the line when a defect is found. This detection is the first step in Jidoka. A machine performing the same defect detection process is engaged in autonomation.\nOnce the line is stopped a supervisor or person designated to help correct problems gives immediate attention to the problem the worker or machine has discovered. To complete Jidoka, not only is the defect corrected in the product where discovered, but the process is evaluated and changed to remove the possibility of making the same mistake again. One solution to the problems can be to insert a \"mistake-proofing\" device somewhere in the production line. Such a device is known as poka-yoke.\nRelationship with just-in-time.\nTaiichi Ohno and Sakichi Toyoda, originators of the TPS and practices in the manufacturing of textiles, machinery and automobiles considered just-in-time manufacturing and Autonomation as the pillars upon which TPS is built. Jeffrey Liker and David Meier indicate that Jidoka or \"the decision to stop and fix problems as they occur rather than pushing them down the line to be resolved later\" is a large part of the difference between the effectiveness of Toyota and other companies who have tried to adopt lean manufacturing. Automation, therefore can be said to be a key element in successful Lean Manufacturing implementations.\nFor just-in-time (JIT) systems, it is absolutely vital to produce with zero defects, or else these defects can disrupt the production process - or the orderly flow of work.\nJIT and Lean Manufacturing are always searching for targets for continuous improvement in its quest for quality improvements, finding and eliminating the causes of problems so they do not continually crop up.\nJidoka involves the automatic detection of errors or defects during production. When a defect is detected the halting of the production forces immediate attention to the problem.\nThe halting causes slowed production but it is believed that this helps to detect a problem earlier and avoids the spread of bad practices.\nEtymology.\nThe word \"autonomation\" 自働化, a loan word from the Sino-Japanese vocabulary, is a portmanteau of \"autonomous\" and \"automation\" 自動化, which is written using three kanji characters: 自（じ ji） \"self\", 動（どう dou）movement, and 化（か ka）\"-ization\". In the Toyota Production System, the second character is replaced with 働（どう dou） \"work\", which is a character derived by adding a radical representing \"human\" to the original 動.\nZenjidoka.\n\"Zenjidoka\" (全自働化) is described as \"taking \"jidoka\" all the way to the customer\" and refers to extended practices in which sales, service and technical staff also have power to interrupt production to correct faults.", "Engineering,_Manufacturing": 0.9996290207, "qwen": "Yes"}
{"id": "7389351", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=7389351", "title": "MEMS thermal actuator", "text": "A MEMS thermal actuator is a microelectromechanical device that typically generates motion by thermal expansion amplification. A small amount of thermal expansion of one part of the device translates to a large amount of deflection of the overall device. Usually fabricated out of doped single crystal silicon or polysilicon as a complex compliant member, the increase in temperature can be achieved internally by electrical resistive heating or by a heat source capable of locally introducing heat. Microfabricated thermal actuators can be integrated into micromotors.", "Engineering,_Manufacturing": 1.0000076294, "qwen": "Yes"}
{"id": "67944543", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=67944543", "title": "Design prototyping", "text": "Design prototyping in its broader definition comprises the actions to make, test and analyse a prototype, a model or a mockup according to one or various purposes in different stages of the design process. Other definitions consider \"prototyping\" as the methods or techniques for making a prototype (e.g., rapid prototyping techniques), or a stage in the design process (prototype development, prototype or prototyping). The concept of \"prototyping\" in design disciplines' literature is also related to the concepts of \"experimentation\" (i.e., an iterative problem-solving process of trying, failing and improving), and \"Research through Design (RtD)\" (i.e., designers make a prototype with the purpose of conducting research and generating knowledge while trying it, rather than aiming to improving it to become a final product).\nBackground.\nInitial references to the concept of prototyping in design could be traced to the proceedings of the \"Conference on Design Methods\" in 1962:\nIn 1968, Bruce Archer, a relevant figure in the \"Design Methods Movement\" describes the design process. One of the stages of the process is called \"Prototype development\" and it indicates activities to build and test a prototype. Thus, it would be possible to say that from a design methods' perspective, \"prototyping\" recalls a process in which a prototype is built, tried out and tested. In the same line, additional references to prototyping can be found in later editions of the Design Research Society's Conferences. For example, referring to build models and use them to consult people out of the design team, review the model and make decisions on how to modify the design proposal; or describing modelling (creating a model) and model simulation.\nHowever, one of the first documented uses of the term \"prototyping\" linked to a design process appears in 1983 in \"A systematic look at prototyping\" in the field of information systems and software development. The work of Floyd was inspired by the discussions among the scholars who were preparing the \"Working Conference on Prototyping.\" It focuses on \"prototype\" as a process, rather than the artefact and how prototyping could be applied to the full solution (or product) or parts of it seeking to improve the final output. Although this work was not developed within the design discipline, it provides a comprehensive characterisation of prototyping by defining its steps, purposes and strategies. Moreover, it serves as a referent to further studies of design prototyping. \nLater, around the year of 1990, the availability of methods for rapidly manufacturing models and prototypes stimulated the publication of a great body of literature dedicated to rapid prototyping techniques and technologies (e.g., 3D printing). Technologies for additive manufacturing (i.e., adding material) or substractive manufacturing (i.e., removing material) together with the use of software for computer-aided design (CAD), leveraged prototype building but also the fabrication of products in limited numbers.\nAlong the years, further efforts have been dedicated to characterising prototyping in design disciplines in the fields of interaction design, experience design, product design and service design, as well as in product-design-related fields such as engineering/mechanical design. In 2000, designers from IDEO described \"experience prototyping,\" introducing types of design representations and methods that allow to simulate aspects of an interaction that people experience by themselves. Experience prototyping can combine various types of prototypes such as spaces, products and interfaces to resemble what the real experience could be like. Around the year of 2010, studies were developed to examine the prototyping of services theorising from the growing practice of service design, which later in 2018 were also used as a reference for service design practitioners.\nPrototyping cycle.\nPrototyping is developed in an iterative cycle of making, testing and analysing which allows to examine dimensions of a solution before its future implementation, anticipating to possible issues and improving them earlier in the process. This cycle can be portrayed the following steps: \nOne example of this cycle could be the design of a digital interface in the early stages of the process applying paper prototyping. In this case, prototyping may seek to explore and evaluate multiple alternatives of ideas with the users as fast and cheap as possible, before investing time to program it. Thus, the prototypes will represent the structure of the interface by using simple forms and text to indicate the elements (1). A common technique for creating prototypes of digital interfaces would be to sketch wireframes in paper (2). The team will meet with a potential user and the wireframes will be presented by the design researcher. The user will simulate to click the elements and explain the actions that intends to do while moving to other sheets that represent other screens in the navigation flow (3). The feedback gathered will be used to make decisions on the aspects that need to be modified and the layout of the interface will be updated (4).\nCharacteristics of prototyping.\nTo prepare for prototyping, some aspects need to be decided. For this purpose, it is useful to individualise and consider various characteristics that will allow identifying how prototyping should be developed according to the design needs. In this regard, the prototyping framework proposed by Blomkvist and Holmid could provide some guidelines. As a result of a literature review, they identify a set of characteristics which are:\nPosition in the process.\nWhilst for some scholars prototyping was happening in a particular stage of the design process, the importance of prototyping has been gaining relevance as a continuous activity since the early stages of the process. Considering in which moment of the process prototyping is going to be developed will guide decisions on its purpose and further characteristics of prototyping.\nPurpose.\nPrototyping can be developed according to different aims of the design process that influence decisions such as what variables of the prototype are going to be examined and who is going to be involved in the testing session. For example, in the early stages of the process, the need could be to explore various ideas within the design team and prototypes may be created fast and with little resources, while at the end of the process the functionality of the solution may be evaluated with future users so the prototype would largely resemble its final version.\nSome of the purposes of prototyping identified by different authors are:\nStakeholder.\nA prototyping session can involve a variety of people related to the solution. Internal to the organisation, the participants could range from the members of the design team to colleagues from other departments and managers. External to the organisation, prototyping could involve future users and clients, and representatives from other organisations. The selection of the participants would depend on the purposes of prototyping. For instance, a prototyping session for exploration could be developed internally with colleagues in order to get quick feedback about initial design proposals. Another example would be to involve users in co-design prototyping sessions in order to explore proposals directly with future users.\nActivity.\nThe activity refers to the method that would be used for testing a prototype, the context in which it is going to occur, and the strategies for testing in relation to what would be the real conditions of use of the solution.\nPrototype.\nPrototypes can represent one component of a future solution such as \"(Inter)actions, service processes, experiences, physical objects, environments, spaces, architecture, digital artifacts and software, ecosystems, [or] (business) value\" or comprise various of these components.\nMoreover, a prototype can reflect one or multiple dimensions of the future solution and a variety of aspects could be considered. A simple approach would be to think on the \"fidelity,\" meaning how close the prototype resembles to the final solution (blom)(stick). More comprehensive approaches can be considered through multiple dimensions. For instance, Houde and Hill describe the “role” (i.e., functionality for the user), “look and feel” (i.e., sensory, and experiential aspects), “implementation” (i.e., performance of the solution). Lim, Stolterman and Tenenberg propose a classification of prototypes according to “filtering dimensions: functionality, interactivity, and spatial structure\"; and “manifestation dimensions:materials, resolution, and scope\". They suggest these dimensions can be pondered in order to decide how the prototype should be.", "Engineering,_Manufacturing": 0.9997560382, "qwen": "Yes"}
{"id": "67959451", "revid": "29221587", "url": "https://en.wikipedia.org/wiki?curid=67959451", "title": "2021–22 UEFA Europa Conference League qualifying phase and play-off round (Main Path)", "text": "This page summarises the Main Path matches of the 2021–22 UEFA Europa Conference League qualifying phase and play-off round.\nTimes are CEST , as listed by UEFA (local times, if different, are in parentheses).\nFirst qualifying round.\nSummary.\n\n\nMatches.\n\"FCI Levadia won 4–2 on aggregate.\"\n\"Puskás Akadémia won 3–1 on aggregate.\"\n\"Drita won 3–1 on aggregate.\"\n\"Sūduva won 2–1 on aggregate.\"\n\"Birkirkara won 2–1 on aggregate.\"\n\"FC Santa Coloma won 5–1 on aggregate.\"\n\"Velež Mostar won 4–2 on aggregate.\"\n\"Domžale won 2–1 on aggregate.\"\n\"Shkupi won 3–1 on aggregate.\"\n\"Dinamo Batumi won 7–0 on aggregate.\"\n\"Partizani won 8–4 on aggregate.\"\n\"Maribor won 2–0 on aggregate.\"\n\"Laçi won 3–1 on aggregate.\"\n\"Milsami Orhei won 1–0 on aggregate.\"\n\"KuPS won 5–1 on aggregate.\"\n\"Žilina won 6–3 on aggregate.\"\n\"FH won 3–1 on aggregate.\"\n\"Śląsk Wrocław won 4–1 on aggregate.\"\n\"RFS won 6–5 on aggregate.\"\n\"Larne won 2–0 on aggregate.\"\n\"Ararat Yerevan won 3–1 on aggregate.\"\n\"Sutjeska won 2–1 on aggregate.\"\n\"Petrocub Hîncești won 2–1 on aggregate.\"\n\"Vllaznia won 4–3 on aggregate.\"\n\"Bohemians won 4–1 on aggregate.\"\n\"The New Saints won 3–1 on aggregate.\"\n\"1–1 on aggregate. Gżira United won 5–3 on penalties.\"\n\"Kauno Žalgiris won 2–0 on aggregate.\"\n\"Dundalk won 5–0 on aggregate.\"\n\"Spartak Trnava won 4–3 on aggregate.\"\n\"Liepāja won 5–2 on aggregate.\"\n\"Breiðablik won 5–2 on aggregate.\"\n\"Honka won 3–1 on aggregate.\"\nSecond qualifying round.\nSummary.\n\n\n\nMatches.\n\"KuPS won 5–4 on aggregate.\"\n\"2–2 on aggregate. Shakhter Karagandy won 5–3 on penalties.\"\n\"Hapoel Be'er Sheva won 6–0 on aggregate.\"\n\"Žilina won 5–3 on aggregate.\"\n\"Čukarički won 2–0 on aggregate.\"\n\"Maccabi Tel Aviv won 3–1 on aggregate.\"\n\"Astana won 3–2 on aggregate.\"\n\"Sivasspor won 2–0 on aggregate.\"\n\"AEL Limassol won 2–0 on aggregate.\"\n\"Sochi won 7–2 on aggregate.\"\n\"Elfsborg won 9–0 on aggregate.\"\n\"RFS won 5–0 on aggregate.\"\n\"Dinamo Batumi won 4–2 on aggregate.\"\n\"Partizan won 3–0 on aggregate.\"\n\"Dundalk won 4–3 on aggregate.\"\n\"Rijeka won 3–0 on aggregate.\"\n\"Viktoria Plzeň won 4–2 on aggregate.\"\n\"The New Saints won 10–1 on aggregate.\"\n\"Domžale won 2–1 on aggregate.\"\n\"0–0 on aggregate. CSKA Sofia won 3–1 on penalties.\"\n\"Santa Clara won 5–0 on aggregate.\"\n\"Hibernian won 5–1 on aggregate.\"\n\"Larne won 3–2 on aggregate.\"\n\"Gent won 4–2 on aggregate.\"\n\"Bohemians won 4–0 on aggregate.\"\n\"2–2 on aggregate. Velež Mostar won 3–2 on penalties.\"\n\"Qarabağ won 1–0 on aggregate.\"\n\"1–1 on aggregate. Lokomotiv Plovdiv won 3–2 on penalties.\"\n\"Śląsk Wrocław won 7–5 on aggregate.\"\n\"Laçi won 1–0 on aggregate.\"\n\"Feyenoord won 3–2 on aggregate.\"\n\"Basel won 5–0 on aggregate.\"\n\"Osijek won 1–0 on aggregate.\"\n\"Breiðablik won 3–2 on aggregate.\"\n\"1–1 on aggregate. Olimpija Ljubljana won 5–4 on penalties.\"\n\"Hammarby won 4–1 on aggregate.\"\n\"Molde won 3–2 on aggregate.\"\n\"Újpest won 5–2 on aggregate.\"\n\"0–0 on aggregate. Raków Częstochowa won 4–3 on penalties.\"\n\"1–1 on aggregate. Spartak Trnava won 4–3 on penalties.\"\n\"Rosenborg won 6–1 on aggregate.\"\n\"Copenhagen won 9–1 on aggregate.\"\n\"Vojvodina won 2–0 on aggregate.\"\n\"Tobol won 4–3 on aggregate.\"\n\"Aberdeen won 5–3 on aggregate.\"\nThird qualifying round.\nSummary.\n\n\nMatches.\n\"Sivasspor won 3–2 on aggregate.\"\n\"KuPS won 5–4 on aggregate.\"\n\"3–3 on aggregate. Partizan won 4–2 on penalties.\"\n\"Hapoel Be'er Sheva won 5–2 on aggregate.\"\n\"Santa Clara won 3–0 on aggregate.\"\n\"Basel won 6–1 on aggregate.\"\n\"IF Elfsborg won 5–2 on aggregate.\"\n\"0–0 on aggregate. Shakhter Karagandy won 3–1 on penalties.\"\n\"Paços de Ferreira won 4–1 on aggregate.\"\n\"Feyenoord won 6–0 on aggregate.\"\n\"Gent won 3–2 on aggregate.\"\n\"Rijeka won 5–2 on aggregate.\"\n\"Aberdeen won 5–3 on aggregate.\"\n\"4–4 on aggregate. Trabzonspor won 4–3 on penalties.\"\n\"PAOK won 3–2 on aggregate.\"\n\"5–5 on aggregate. Viktoria Plzeň won 4–1 on penalties.\" \n\"Raków Częstochowa won 1–0 on aggregate.\"\n\"Copenhagen won 5–3 on aggregate.\"\n\"Hammarby IF won 6–4 on aggregate.\"\n\"Žilina won 6–0 on aggregate.\"\n\"CSKA Sofia won 5–3 on aggregate.\"\n\"LASK won 7–1 on aggregate.\"\n\"Qarabağ won 2–1 on aggregate.\"\n\"Maccabi Tel Aviv won 1–0 on aggregate.\"\n\"Rosenborg won 8–2 on aggregate.\"\n\"Anderlecht won 5–1 on aggregate.\"\n\"Vitesse won 4–3 on aggregate.\"\nPlay-off round.\nSummary.\n\n\nMatches.\n\"Qarabağ won 4–1 on aggregate.\"\n\"4–4 on aggregate. Basel won 4–3 on penalties.\"\n\"CSKA Sofia won 3–2 on aggregate.\"\n\"Tottenham Hotspur won 3–1 on aggregate.\"\n\"Rennes won 5–1 on aggregate.\"\n\"Vitesse won 5–4 on aggregate.\"\n\"LASK won 3–1 on aggregate.\"\n\"Maccabi Tel Aviv won 4–1 on aggregate.\"\n\"PAOK won 3–1 on aggregate.\"\n\"Union Berlin won 4–0 on aggregate.\"\n\"Feyenoord won 6–3 on aggregate.\"\n\"Gent won 3–1 on aggregate.\"\n\"Copenhagen won 7–1 on aggregate.\"\n\"Partizan won 3–2 on aggregate.\"\n\"Roma won 5–1 on aggregate.\"\n\"Anorthosis Famagusta won 3–1 on aggregate.\"\n\"Jablonec won 8–1 on aggregate.\"", "Engineering,_Manufacturing": 0.9999610186, "qwen": "Yes"}
{"id": "17496174", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=17496174", "title": "Brandt (brand)", "text": "Brandt is a French brandname producing various home equipment, created in 1924 by Edgar Brandt as a part of Hotchkiss-Brandt. Today, the company currently is owned by Cevital.\nManufacturing facilities.\ncurrent :\nformer :", "Engineering,_Manufacturing": 0.9999859333, "qwen": "Yes"}
{"id": "1059258", "revid": "11308236", "url": "https://en.wikipedia.org/wiki?curid=1059258", "title": "Ford MA", "text": "The Ford MA Concept concept car was a 2002 minimalist design exercise drawn by Jose Paris and championed by Ford's VP of design J. Mays. It was exhibited as an art object in museums as well as a traditional concept car in auto shows. It received an IDSA Silver Industrial Design Excellence Award in 2003.\nThe MA displayed many unusual automotive practices. It had the shape of a low slung two seat roadster with no top, but it was powered by an electric motor. The design was flexible enough, though, to accommodate a small internal combustion engine.\nVery few of the parts were painted and there were none of the usual hydraulic fluids or industrial adhesives common in most cars, making it 96% recyclable.\nIt was designed to be assembled and disassembled easily with a minimal amount of equipment. There were no welds holding it together: Instead, its 500 or so pieces of bamboo, aluminum and carbon fibre were held together with 364 titanium bolts. The total weight was said to be .\nSome automotive columnists have presented the Ford MA as the forerunner to a small series kit car, much like the Lotus Seven. Others have called it an IKEA-mobile.", "Engineering,_Manufacturing": 0.9936423898, "qwen": "Yes"}
{"id": "10234884", "revid": "40524794", "url": "https://en.wikipedia.org/wiki?curid=10234884", "title": "Deep drawing", "text": "Deep drawing is a sheet metal forming process in which a sheet metal blank is radially drawn into a forming die by the mechanical action of a punch. It is thus a shape transformation process with material retention. The process is considered \"deep\" drawing when the depth of the drawn part exceeds its diameter. This is achieved by redrawing the part through a series of dies. \nThe flange region (sheet metal in the die shoulder area) experiences a radial drawing stress and a tangential compressive stress due to the material retention property. These compressive stresses (hoop stresses) result in flange wrinkles (wrinkles of the first order). Wrinkles can be prevented by using a blank holder, the function of which is to facilitate controlled material flow into the die radius. Deep drawing presses, especially in the Aerospace and Medical industries, require unparalleled accuracy and precision. Sheet hydroforming presses do complex draw work. Bed size, tonnage, stroke, speed, and more can be tailored to your specific draw forming application.\nProcess.\nThe total drawing load consists of the ideal forming load and an additional component to compensate for friction in the contacting areas of the flange region and bending forces as well as unbending forces at the die radius. The forming load is transferred from the punch radius through the drawn part wall into the deformation region (sheet metal flange). In the drawn part wall, which is in contact with the punch, the hoop strain is zero whereby the plane strain condition is reached. In reality, mostly the strain condition is only approximately plane. Due to tensile forces acting in the part wall, wall thinning is prominent and results in an uneven part wall thickness, such that the part wall thickness is lowest at the point where the part wall loses contact with the punch, i.e., at the punch radius.\nThe thinnest part thickness determines the maximum stress that can be transferred to the deformation zone. Due to material volume constancy, the flange thickens and results in blank holder contact at the outer boundary rather than on the entire surface. The maximum stress that can be safely transferred from the punch to the blank sets a limit on the maximum blank size (initial blank diameter in the case of rotationally symmetrical blanks). An indicator of material formability is the limiting drawing ratio (LDR), defined as the ratio of the maximum blank diameter that can be safely drawn into a cup without flange to the punch diameter. Determination of the LDR for complex components is difficult and hence the part is inspected for critical areas for which an approximation is possible. During severe deep drawing the material work hardens and it may be necessary to anneal the parts in controlled atmosphere ovens to restore the original elasticity of the material.\nCommercial applications of this metal shaping process often involve complex geometries with straight sides and radii. In such a case, the term stamping is used in order to distinguish between the deep drawing (radial tension-tangential compression) and stretch-and-bend (along the straight sides) components. Deep drawing is always accompanied by other forming techniques within the press. These other forming methods include:\nOften components are partially deep drawn in order to create a series of diameters throughout the component (as in the image of the deep draw line). It common use to consider this process as a cost saving alternative to turned parts which require much more raw material. \nThe sequence of deep drawn components is referred to as a \"deep draw line\". The numbers of components that form the deep draw line is given by the quantity of \"stations\" available in the press. In the case of mechanical presses this is determined by the number of cams on the top shaft.\nFor high precision mass productions, it is always advisable to use a transfer press also known as eyelet press. The advantage of this type of press, in respect to conventional progressive presses, is that the parts are transferred from one die to the next by means of so-called \"fingers\". Not only do the fingers transfer the parts but they also guide the component during the process. This allows parts to be drawn to the deepest depths with the tightest tolerances.\nOther types of presses: \nVariations.\nDeep drawing has been classified into \"conventional\" and \"unconventional\" deep drawing. The main aim of any unconventional deep drawing process is to extend the formability limits of the process. Some of the unconventional processes include hydromechanical deep drawing, Hydroform process, Aquadraw process, Guerin process, Marform process and the hydraulic deep drawing process to name a few.\nThe Marform process, for example, operates using the principle of rubber pad forming techniques. Deep-recessed parts with either vertical or sloped walls can be formed. In this type of forming, the die rig employs a rubber pad as one tool half and a solid tool half, similar to the die in a conventional die set, to form a component into its final shape. Dies are made of cast light alloys and the rubber pad is 1.5-2 times thicker than the component to be formed. For Marforming, single-action presses are equipped with die cushions and blank holders. The blank is held against the rubber pad by a blank holder, through which a punch is acting as in conventional deep drawing. It is a double-acting apparatus: at first the ram slides down, then the blank holder moves: this feature allows it to perform deep drawings (30-40% transverse dimension) with no wrinkles.\nIndustrial uses of deep drawing processes include automotive body and structural parts, aircraft components, utensils and white goods. Complex parts are normally formed using progressive dies in a single forming press or by using a press line.\nWorkpiece materials and power requirements.\nSofter materials are much easier to deform and therefore require less force to draw. The following is a table demonstrating the draw force to percent reduction of commonly used materials.\nTool materials.\nPunches and dies are typically made of tool steel, however cheaper (but softer) carbon steel is sometimes used in less severe applications. It is also common to see cemented carbides used where high wear and abrasive resistance is present.\nAlloy steels are normally used for the ejector system to kick the part out and in durable and heat resistant blankholders.\nLubrication and cooling.\nLubricants are used to reduce friction between the working material and the punch and die. They also aid in removing the part from the punch. Some examples of lubricants used in drawing operations are heavy-duty emulsions, phosphates, white lead, and wax films. Plastic films covering both sides of the part while used with a lubricant will leave the part with a fine surface.", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "10238320", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=10238320", "title": "Incremental sheet forming", "text": "Incremental sheet forming (or ISF, also known as Single Point Forming) is a sheet metal forming technique where a sheet is formed into the final workpiece by a series of small incremental deformations. However, studies have shown that it can be applied to polymer and composite sheets too. Generally, the sheet is formed by a round tipped tool, typically 5 to 20mm in diameter. The tool, which can be attached to a CNC machine, a robot arm or similar, indents into the sheet by about 1 mm and follows a contour for the desired part. It then indents further and draws the next contour for the part into the sheet and continues to do this until the full part is formed. ISF can be divided into variants depending on the number of contact points between tool, sheet and die (in case there is any). The term Single Point Incremental Forming (SPIF) is used when the opposite side of the sheet is supported by a faceplate and Two Point Incremental Forming (TPIF) when a full or partial die supports the sheet.\nTypes.\nSingle-point incremental forming (SPIF) and double-sided incremental forming (DSIF) are the two variants of the IF process. In the DSIF process, two tools are used to form the sheet on either side, while the SPIF process only uses a tool on one side of the sheet. Thus, a component having features on either side of the sheet, e.g., an inverted cone can be effectively formed by the DSIF process. \nAdvantages over conventional sheet metal forming.\nBecause the process can be controlled entirely by CNC processes no die is required as is in traditional sheet metal forming. The elimination of the die in the manufacturing process reduces the cost per piece and decreases turnaround time for low production runs because the need to manufacture a die is eliminated. However, for high production runs the time and cost to produce a die is absorbed by the higher per piece speed and lower per piece cost.\nSeveral authors recognize that the formability of metal materials under the localized deformation imposed by incremental forming is better than in conventional deep drawing. In contrast, there is a loss of accuracy with the ISF process.\nImplementation.\nThe ISF process is generally implemented by clamping a sheet in the XY plane, which is free to move along the Z axis. The tool moves in the XY plane and is coordinated with movements in the Z axis to create the desired part. It is often convenient to retrofit a CNC milling machine to accommodate the process. Spherical, flat-bottomed, and parabolic tool profiles can be used to achieve differing surface finishes and forming limits.\nThe machine employs a combination of stretch forming by drawing the sheet incrementally down over a die, with the CNC tool approach described above. This is said to produce a more even distribution of thickness of the material. The process is well suited to one-off manufacture though difficulties in simulating the process mean that toolpaths are complex and time-consuming to determine.\nFord Motor Company has recently released Ford Freeform Fabrication Technology, a two-point incremental sheet-forming technique being implemented in the rapid prototyping of automotive parts. Complex shapes such as the human face and cranial implants have been manufactured successfully using this manufacturing process. Advances in the technology are expected to increase adoption in the near future by other sheet metal-reliant manufacturers.\nApplications.\nIncremental forming (IF) is a recent manufacturing process having a wide range of applications in the following areas.\nList of process parameters.\nThe mechanics of the process is influenced by many parameters, including:\nCurrent research.\nResearch is underway at several universities. The most common implementation is to outfit a traditional milling machine with the spherical tool used in the ISF process. Key research areas include", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "21760978", "revid": "952471735", "url": "https://en.wikipedia.org/wiki?curid=21760978", "title": "GKD Legend", "text": "The GKD LEGEND is a light-weight performance sports car manufactured by British company GKD Sports Cars, based in Boughton Monchelsea, near Maidstone with workshops at Lenham. The LEGEND is available in component form, or fully built. It was the first seven inspired car on the market using BMW E36/46 running gear.\nHistory.\nThe GKD LEGEND was a byproduct of the work to convert the GKD EVOLUTION to BMW donor parts. Creator Peter Lathrope saw a gap in the market for a BMW based seven and developed the LEGEND. After its first show preview at Exeter kit car show the press hailed the car as \"the next big thing\" in the kit car market as most of the Lotus Seven Style cars are still Ford Sierra based. After the success of the initial Legend GKD Sports Cars bridged the gap between the Legend and the Evolution by introducing a new variant known as the Legend six. This model is a slightly longer chassis to accommodate the BMW straight 6 engine and running gear but still keeping the classic 7 style.\nCar components.\nThe car uses a donor pack from a BMW 3 Series. The donor pack includes differential, half-shafts, brakes, steering column and lower steering shaft and if required, engine and gearbox. The chassis comes with BMW engine mounts already welded to the chassis to ease fitment.\nKits start at around £2,995, with an estimated build price from £8,000 (as of late 2008).\nFully built cars are also supplied to foreign markets, countering crash test requirements. Prices start at around £10,500, with the donor pack left to the customer to source. Or GKD can supply all the donor pack components to order.\nThe body shell is made from GRP fibreglass, with a bespoke chassis housing the engine and suspension.\nExample cars.\nThe LEGEND can utilise most engines. The chart below indicates performance with a BMW E46 1.8 with different states of tune. Also including the Legend six with the E46 M3 engine and running gear", "Engineering,_Manufacturing": 0.9992054105, "qwen": "Yes"}
{"id": "21795622", "revid": "44292628", "url": "https://en.wikipedia.org/wiki?curid=21795622", "title": "Sigrity", "text": "Sigrity, acquired by Cadence Design Systems in 2012 for $80M, supplies software for IC package physical design and for analyzing power integrity, signal integrity and design stage electromagnetic interference (EMI). Analysis is performed on chips, IC packages and printed circuit boards.\nOverview.\nSigrity began operations with a 1997 award from the National Science Foundation for simulation using electromagnetic computation techniques targeting electronic structures with hybrid solver techniques. The IC package physical layout product line was acquired from Synopsys in 2006.\nThe 2017 revision of Cadence’s Sigrity product introduces several features specifically designed to speed up PCB power and signal integrity signoff. In 2016, Cadence expanded the portfolio with an upgraded serial link analysis flow including an IBIS-AMI modeling-building technology, USB 3.1 (Gen 2) compliance kit, and cut-and-stitch model extraction technology to segment long serial links into sections that should be modeled using 3D full-wave and sections that can be modeled using hybrid extraction technology. In 2015, Cadence released the Sigrity Parallel Computing 4-pack which enabled efficient product creation with 3X speedup in signoff-accurate PCB extraction, an updated power-aware system signal integrity (SI) feature which supports LPDDR4 analysis with full JEDEC compliance checking, and flexible licensing options.", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "24201843", "revid": "39638887", "url": "https://en.wikipedia.org/wiki?curid=24201843", "title": "Mitchell Electronics", "text": "Mitchell Electronics Incorporated, founded in 1979, is a manufacturer of equipment to test and run servomotors, encoders and resolvers as well as various third-party electronic devices. Corporate headquarters are located in Athens, Ohio, which is also where manufacturing takes place. The company is an associate member of the Electrical Apparatus Service Association (EASA), an international electromechanical trade organization.\nCompany history.\nMitchell Electronics began in 1979 by providing custom designed industrial electronic systems to the motion control. By 1983 the company had progressed to offering standard computer based industrial products to end users and to original equipment manufacturers as components in their products and ten years later began offering encoder test equipment. In 1999 the company began offering a suite of hardware and Windows-based software to designed to test additional types of encoders as well as resolvers and other servo feedback devices.\nIn 2001 the company introduced a line of equipment designed to provide repair shops and plant maintenance personnel the ability to test run many types of servo motors with one common drive device. A patent was later issued to the company for \"an apparatus that allows a non-standard brushless motor to be driven with a standard drive amplifier.\"\nEquipment and Services.\nMitchell Electronics' products include the TI-3000 line of servomotor run-rest equipment, TI-4000EX (formerly PulsePro) line of encoder test equipment, TI-5000EX (formerly TI-5000) line of PC based servo feedback test equipment and software and the TI-7000 line of servo feedback field test equipment. Most major motor and feedback manufacturer's devices are supported by Mitchell Electronics equipment, which is widely used in the motor and feedback repair field and other industrial applications, such as CNC machining and robotics, around the world. Notable manufacturing applications include use by Ford, General Mills, and Sturm Ruger.\nThe company additionally provides consulting, hardware and software development and manufacturing services to various third party distributors and OEM manufacturers, generally also in the electronics field, such as Avtron and certain divisions of Danaher. Mitchell Electronics equipment is also used in servomotor operation and service training courses.", "Engineering,_Manufacturing": 0.9998799562, "qwen": "Yes"}
{"id": "24203665", "revid": "11308236", "url": "https://en.wikipedia.org/wiki?curid=24203665", "title": "Lens board", "text": "A lens board or lensboard is a photographic part used for securing a lens to the front standard of a large format view camera. The lens board itself is usually flat, square, and made of metal (most commonly aluminum), wood, or plastic. The lens board will have a hole of various diameters drilled dead center on the board. A lens board typically varies between 1 and 4 millimeters in thickness. The overall size and shape of the lens board depends on the brand of camera and film format used. Some cameras will use 2 to 4 screws to secure the lens board to the front standard of the view camera, most commonly however, the lens board will be secured by one or more locking levers or tabs to allow tool-less removal of the lens board. The rear surface of a lens board is usually painted matte black to keep light entering the camera through the lens during exposure from reflecting off the surface and interfering with the projected image.\nWhile most lens boards are flat, some are recessed to accommodate wider focal length lenses which must be positioned closer to the film plane. A recessed lens board effectively reduces the flange focal distance of a camera.\nSizes.\nDepending on the size and focal length of a particular lens, a certain diameter of hole is drilled in the center of the lens board to accommodate the shutter assembly. Lens boards are typically available pre-drilled by the camera manufacturer, however, if no replacement lens board is available from a camera manufacturer, then one can be custom fabricated by a machinist. \nNearly all large format leaf shutters made since the 1990s are manufactured by the Nidec Copal Corporation, therefore the diameter of hole drilled is commonly referred to as the ‘Copal Number’.\nThe Copal sizes are as follows:\nThe origin Compur/Compound sizes are as follows:\nLens mounting.\nLenses are fitted to a lens board by placing the shutter assembly through the front of the board and securing the shutter assembly by threading a locknut to rear of the shutter. A front lens element will thread onto the mounted shutter and if necessary, a second lens element will thread onto the rear of the mounted shutter. This procedure can be accomplished by a camera technician, or by an end-user with the appropriate tools.\nOther uses.\nLens boards are used in photographic enlargers to secure an enlarging lens to the focus stage of the device.\nSimilar to large format photographic view cameras, a lens board is utilized by some reprographic cameras in the printing industry.\nLens boards may also be used by some medical and scientific imaging devices.", "Engineering,_Manufacturing": 0.9998754263, "qwen": "Yes"}
{"id": "35864779", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=35864779", "title": "Maverick Technologies", "text": "Maverick Technologies is an industrial automation, enterprise integration, operational consulting and sustaining services provider. The company has over 500 employees and 18 U.S. locations and operations worldwide and is the largest independent systems integrator in North America.\nHistory.\nIn 1989, Paul Galeski founded MAGNUM Technologies. In 1995, Inc. Magazine cited MAGNUM Technologies as one of the nation's fastest growing companies. In 1997, MAGNUM Technologies was sold to General Electric, where it became a GE Industrial Systems Division subsidiary. Paul Galeski continued to serve as President of the GE Industrial Systems Division until he left GE in early 1999.\nLater that year, Paul Galeski founded MAVERICK Technologies and acquired Software Architects, also an Inc. 500 company. Between 2002 and 2004, MAVERICK Technologies acquired RHES Inc. and Professional Maintenance Consultants. In 2005, they acquired GEAS (General Electric Automation Services) and CF Picou, Inc. Between 2006 and 2009, MAVERICK Technologies acquired LaPlace Technologies, Mission Controls and Program4 Engineering.\nMAVERICK Technologies partnered with MPE Industrial Automation Europe and MPE Industrial Automation Asia to form the Global System Integrators Alliance (GSIA), a partnership that connects its members to more than 30 locations and 700 professionals worldwide. MAVERICK began international operations in the Netherlands and Thailand in 2008 and Singapore in 2009.\nAs of 2011, MAVERICK Technologies had completed 10,000 projects in 45 countries on six continents, employs over 500 people globally and has been listed as one of the Inc. 500 fastest growing companies five times.\nIn 2016, MAVERICK Technologies was acquired by Rockwell Automation.\nServices.\nMAVERICK Technologies provides industrial automation, enterprise integration and strategic manufacturing solutions to manufacturing and processing industries worldwide.\nIt serves biofuel, chemical and petrochemical, upstream and downstream oil and gas, bakery, beverage, confectionery, dairy, protein, consumer packaged goods, high-tech manufacturing, life sciences, and power and utilities industries through a network of employees and international partners.\nIndustrial automation.\nMAVERICK’s industrial automation services comprise automation solutions including automation engineering, process automation, industrial automation integration, regulatory-compliant systems and services and distributed control system migration; field services, which include construction management, technician/calibration, outage services and planning, maintenance and installation; and advanced process control services.\nEnterprise integration.\nMAVERICK’s enterprise integration services comprise manufacturing IT services, including demand planning, production planning and scheduling, sourcing and procurement, logistics and distribution, manufacturing execution/production management, manufacturing intelligence and quality management; and business solutions, which include Microsoft Dynamics AX, customer relationship management (CRM), enterprise manufacturing intelligence (EMI) and enterprise application integration (EAI).\nStrategic manufacturing solutions.\nMAVERICK’s strategic manufacturing solutions comprise sustaining services, including industrial security solutions; and offers operational consulting services, which include operational strategy, productivity improvements, energy optimization and safety.\nPaul Galeski.\nPaul Galeski, CEO and President of MAVERICK Technologies, was named one of Fast Forward's '40 under 40,' and St. Louis Business Journal ‘Who’s Who in Technology,’ a listing of top young St. Louis area executives. In 2002, Galeski was awarded the Illinois Entrepreneur of the Year and later elected to an International Society of Automation (ISA) Fellow appointment.\nGaleski holds a bachelor's degree in electrical engineering from Southern Illinois University, where he is a member of the inaugural class of the SIUE Alumni Hall of Fame and sponsor of the MAVERICK Technologies LLC Scholarship in Engineering. He is a graduate of the GE executive management school and the Harvard Business School President's Program. He is also involved in expert witness testimony, and is a contributing author to Aspatore Books' Inside the Minds, a series of publications that examine C-level business intelligence.", "Engineering,_Manufacturing": 0.9962540865, "qwen": "Yes"}
{"id": "35869309", "revid": "1165381168", "url": "https://en.wikipedia.org/wiki?curid=35869309", "title": "Tamiya connector", "text": "A Tamiya connector is a type of DC power connector, commonly used on radio-controlled model vehicle battery packs, drones and chargers. They are also commonly used on airsoft guns. The connector was designed by Japanese manufacturer Tamiya Corporation.\nThe connector is still available from connector manufacturers such as Molex. The following connectors are compatible with the Tamiya connectors: 19-09-1029 with crimp 02-09-1119 and 19-09-2029 with crimp 02-09-2116.\nWiring.\nThe usual wiring has the positive (red) wire running to the terminal with a square profile, and the negative (black) wire running to the half-circle, half-square terminal. This is true for both genders of connector. The female sockets are in a male housing and the male pins are in a female housing. The male pins (female housing) connector is usually on the battery side.\nIn electrical and electronics engineering, the convention is that gender refers to the metal contact parts of a connector in order to avoid ambiguity. A large number of hobbyist retailers selling these connectors refer to the gender of the plastic housing, which is against convention and can lead to errors. \nIn some cases, Mini-Tamiya connectors are wired in reverse polarity. This is often the case with airsoft guns, where the square profile terminal is the negative terminal and the rounded terminal is the positive terminal.\nSizes.\nThere are two sizes of Tamiya connectors: standard and mini.\nThe outside dimensions of the standard connector is:\nThe outside dimensions of the mini connector is:\nThe standard Tamiya connector uses \"D\" cross-section sheaths for polarisation as seen in the male end above. The mini-Tamiya connector uses one square and one or two round sheaths.\nAdvantages.\nA useful feature of the Tamiya connectors is the locking mechanism which prevents accidental disconnection.\nThe connector physically isolates the positive and negative wires so that the connectors remain safe to use in damp conditions. This makes them safe for use in relatively low-current applications (up to about 15 A) in dirty conditions (for example, model boats or RC cars used outdoors).", "Engineering,_Manufacturing": 0.9995887876, "qwen": "Yes"}
{"id": "36152614", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=36152614", "title": "DigitalOptics Corporation", "text": "DigitalOptics Corporation (DOC) is a San Jose, California-based technology company that designs and manufactures imaging systems for smartphones. DOC’s capabilities include optical design, camera module design and manufacturing, MEMS manufacturing, and image processing algorithms.\nIn 2013, DOC introduced a camera module technology ( mems|cam) with a MEMS-based autofocus actuator. The technology is designed to replace voice coil motor components, while improving speed, power consumption, and precision of the autofocus function.\nDigitialOptics also provides embedded image processing and computational photography algorithms, including its face beautification, face detection, and multi-focus products.\nDigitalOptics Corporation operates as a wholly owned subsidiary of Xperi. DOC consists of the imaging and optics-related businesses acquired by Xperi. since 2005.", "Engineering,_Manufacturing": 0.9982338548, "qwen": "Yes"}
{"id": "38478972", "revid": "45321031", "url": "https://en.wikipedia.org/wiki?curid=38478972", "title": "Spania GTA", "text": "Spania GTA is an automobile design and manufacturing company based in Valencia, Spain. It was founded by Domingo Ochoa, who is also the current CEO of the company.\nThey have designed, developed, and produced the GTA Spano in-house. The first production units were delivered to the customers in 2012, with full scale production expected in 2013.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "6356594", "revid": "46014985", "url": "https://en.wikipedia.org/wiki?curid=6356594", "title": "Probe card", "text": "A probe card (commonly referred to as a DUT board) is used in automated integrated circuit testing. It is an interface between an electronic test system and a semiconductor wafer. \nUse and manufacture.\nA probe card or DUT board is a printed circuit board (PCB), and is the interface between the integrated circuit and a test head, which in turn attaches to automatic test equipment (ATE) (or \"tester\"). Typically, the probe card is mechanically docked to a Wafer testing prober and electrically connected to the ATE . Its purpose is to provide an electrical path between the test system and the circuits on the wafer, thereby permitting the testing and validation of the circuits at the wafer level, usually before they are diced and packaged. It normally comprises a PCB and some form of contact elements, usually metallic.\nA semiconductor manufacturer will typically require a new probe card for each new device wafer and for device shrinks (when the manufacturer reduces the size of the device while keeping its functionality) because the probe card is effectively a custom connector that takes the universal pattern of a given tester and translates the signals to connect to electrical pads on the wafer. For testing of Dynamic random-access memory (DRAM) and Flash memory (FLASH) devices, these pads are typically made of aluminum and are 40–90  per side. Other devices may have flat pads, or raised bumps or pillars made of copper, copper alloys or many types of solders such as lead-tin, tin-silver and others.\nThe probe card must make good electrical contact to these pads or bumps during the testing of the device. When the testing of the device is complete, the prober will index the wafer to the next device to be tested.\nNormally a probe card is inserted into a wafer prober, inside which the position of the wafer to be tested will be adjusted to ensure a precise contact between the probe card and wafer. Once the probe card and the wafer are loaded, a camera in the prober will optically locate several tips on the probe card and several marks or pads on the wafer, and using this information it will align the pads on the device under test (DUT) to the probe card contacts.\nDesign and types.\nProbe cards are broadly classified into needle type, vertical type, and MEMS (Micro Electro-Mechanical System) type depending on shape and forms of contact elements. MEMS type is the most advanced technology currently available. The most advanced type of probe card currently can test an entire 12\" wafer with one touchdown.\nProbe cards or DUT boards are designed to meet both the mechanical and electrical requirements of the particular chip and the specific test equipment to be used. One type of DUT board is used for testing the individual die of a silicon wafer before they are cut free and packaged, and another type is used for testing packaged IC's.\nEfficiency factors.\nProbe card efficiency is affected by many factors. Perhaps the most important factor impacting probe card efficiency is the number of DUTs that can be tested in parallel. Many wafers today are still tested one device at a time. If one wafer had 1000 of these devices and the time required to test one device was 10 seconds and the time for the prober to move from one device to another device was 1 second, then to test an entire wafer would take 1000 x 11 seconds = 11,000 seconds or roughly 3 hours. If however, the probe card and the tester could test 16 devices in parallel (with 16 times the electrical connections) then the test time would be reduced by almost exactly 16 times (to about 11 minutes).\nAdvanced Tester Resource Enhancement (ATRE) is a powerful means of increasing the number of DUTs that can be tested by a probe card in parallel (or in one touchdown during which probe card needles remain in contact with the wafer DUTs). ATRE allows the sharing of tester resources among DUTs using active components, which have the ability to connect and disconnect DUTs from the tester resources. Without ATRE, a single tester resource (power, DC or AC signal) would normally only go directly to one DUT. However by installing ATRE-configured relays (switches) onto the probe card PCB, the tester resource can split or branch out to multiple DUTs. For example in a x4 sharing configuration, 1 power signal is fed into 4 relays whose outputs go to 4 DUTs, respectively. Then by turning each relay ON and OFF sequentially (in the case of a DUT current measurement test), the tester can test each of the 4 DUTs in turn during the same touchdown (without having to move the prober from one device to the other). Therefore a tester that has only 256 power signals will appear to have its resources expanded or enhanced so as to enable it to test 1024 DUTs in one touchdown, thanks to the 1024 onboard relays in the x4 sharing scheme implemented on the probe card. ATRE brings dramatic savings in terms of test time and cost, as it can allow a chip manufacturer or test house to validate more DUTs in one touchdown without the need to purchase a more advanced tester equipped with more resources.\nContamination issues.\nAnother major factor is debris that accumulates on the tips of the probe needles. Normally these are made of tungsten or tungsten/rhenium alloys or advanced palladium based alloys like PdCuAg. Some modern probe cards have contact tips manufactured by MEMS technologies.\nIrrespective of the probe tip material, contamination builds up on the tips as a result of successive touchdown events (where the probe tips make physical contact with the bond pads of the die). Accumulation of debris has an adverse effect on the critical measurement of contact resistance. To return a used probe card to a contact resistance that is acceptable, the probe tips must be spotless. Cleaning can be done offline using an NWR style laser to reclaim the tips by selectively removing the contamination. Online cleaning can be used during testing to optimize the testing results within the wafer or within wafer lots.", "Engineering,_Manufacturing": 0.999951005, "qwen": "Yes"}
{"id": "2437593", "revid": "1110502700", "url": "https://en.wikipedia.org/wiki?curid=2437593", "title": "Hybrid integrated circuit", "text": "A hybrid integrated circuit (HIC), hybrid microcircuit, hybrid circuit or simply hybrid is a miniaturized electronic circuit constructed of individual devices, such as semiconductor devices (e.g. transistors, diodes or monolithic ICs) and passive components (e.g. resistors, inductors, transformers, and capacitors), bonded to a substrate or printed circuit board (PCB). A PCB having components on a Printed Wiring Board (PWB) is not considered a true hybrid circuit according to the definition of MIL-PRF-38534.\nOverview.\n\"Integrated circuit\" as the term is currently used refers to a monolithic IC which differs notably from a HIC in that a HIC is fabricated by inter-connecting a number of components on a substrate whereas an IC's (monolithic) components are fabricated in a series of steps entirely on a single wafer which is then diced into chips. Some hybrid circuits may contain monolithic ICs, particularly Multi-chip module (MCM) hybrid circuits.\nHybrid circuits could be encapsulated in epoxy, as shown in the photo, or in military and space applications, a lid was soldered onto the package. A hybrid circuit serves as a component on a PCB in the same way as a monolithic integrated circuit; the difference between the two types of devices is in how they are constructed and manufactured. The advantage of hybrid circuits is that components which cannot be included in a monolithic IC can be used, e.g., capacitors of large value, wound components, crystals, inductors. In military and space applications, numerous integrated circuits, transistors and diodes, in their die form, would be placed on either a ceramic or beryllium substrate. Either gold or aluminum wire would be bonded from the pads of the IC, transistor, or diode to the substrate.\nThick film technology is often used as the interconnecting medium for hybrid integrated circuits. The use of screen printed thick film interconnect provides advantages of versatility over thin film although feature sizes may be larger and deposited resistors wider in tolerance. Multi-layer thick film is a technique for further improvements in integration using a screen printed insulating dielectric to ensure connections between layers are made only where required. One key advantage for the circuit designer is complete freedom in the choice of resistor value in thick film technology. Planar resistors are also screen printed and included in the thick film interconnect design. The composition and dimensions of resistors can be selected to provide the desired values. The final resistor value is determined by design and can be adjusted by laser trimming. Once the hybrid circuit is fully populated with components, fine tuning prior to final test may be achieved by active laser trimming.\nThin film technology was also employed in the 1960s. Ultra Electronics manufactured circuits using a silica glass substrate. A film of tantalum was deposited by sputtering followed by a layer of gold by evaporation. The gold layer was first etched following the application of a photoresist to form solder compatible connection pads. Resistive networks were formed, also by a photoresist and etching process. These were trimmed to a high precision by selective adonization of the film. Capacitors and semiconductors were in the form of LID (Leadless Inverted Devices) soldered to the surface by selectively heating the substrate from the underside. Completed circuits were potted in a diallyl phthalate resin. Several customized passive networks were made using these techniques as were some amplifiers and other specialized circuits. It is believed that some passive networks were used in the engine control units manufactured by Ultra Electronics for Concorde.\nSome modern hybrid circuit technologies, such as LTCC-substrate hybrids, allow for embedding of components within the layers of a multi-layer substrate in addition to components placed on the surface of the substrate. This technology produces a circuit that is, to some degree, three-dimensional.\nOther electronic hybrids.\nIn the early days of telephones, separate modules containing transformers and resistors were called hybrids or hybrid coils; they have been replaced by semiconductor integrated circuits.\nIn the early days of transistors the term \"hybrid circuit\" was used to describe circuits with both transistors and vacuum tubes; e.g., an audio amplifier with transistors used for voltage amplification followed by a vacuum tube power output stage, as suitable power transistors were not available. This usage, and the devices, are obsolete, however amplifiers that use a tube preamplifier stage coupled with a solid state output stage are still in production, and are called hybrid amplifiers in reference to this.", "Engineering,_Manufacturing": 1.0000002384, "qwen": "Yes"}
{"id": "5315899", "revid": "13501746", "url": "https://en.wikipedia.org/wiki?curid=5315899", "title": "Geunyoung Industry", "text": "Geunyoung Industry Co, Ltd. (hangul:근영산업) is a Korean auto parts company headquartered in Nowon-Dong, Buk-Gu Daegu established in 1977. It makes automotive spare parts products, similar to Hyundai Mobis and SL Corp. The \"Geunyoung Industry\" CEO is brother by Yoo Deok Sool & Yoo Yeong Sool (유덕술, 유영술 형제).", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "3342846", "revid": "42790220", "url": "https://en.wikipedia.org/wiki?curid=3342846", "title": "Rotary wheel blow molding systems", "text": "Rotary wheel blow molding systems are used for the high-output production of a wide variety of plastic extrusion blow molded articles. Containers may be produced from small, single serve bottles to large containers up to 20-30 liters in volume - but wheel machines are often sized for the volume and dimensional demands of a specific container, and are typically dedicated to a narrow range of bottle sizes once built. Multiple parison machines, with high numbers of molds are capable of producing over one million bottles per day in some configurations.\nDescription.\nRotary blow molding \"wheels\" are targeted to the high output production of containers. They are used to produce containers from one to seven layers. View stripe and In Mold Labeling (IML) options are available in some configurations. Rotary wheels, which may contain from six to thirty molds, feature continuously extruded parisons. Revolving sets of blow molds capture the parison or parisons as they pass over the extrusion head. The revolving sets of molds are located on clamp \"stations\".\nRotary wheels come in different variations, including both continuous motion and indexing wheels, and vertical or horizontal variations. Wheel machines are favored for their processing ease, due to having only single (or in some cases, two) parisons, and mechanical repeatability.\nIn some machinery configurations, the molds take on the shape of a \"pie\" sector. Thus, if two or more parisons are used, each blow molded \"log\" has a unique length, requiring special downstream handling and trimming requirements. In other machine configurations, the molds utilize \"book style\" opening mechanisms, allowing multiple parisons of equal length. However, machines of this style typically have lower clamp force, limiting the available applications.\nThe mold close and open actuation is typically carried out through a toggle mechanism linkage that is activated during the rotational process by stationary cams. This mechanical repeatability is considered an advantage by most processors.\nThe method of wheel rotation is typically conducted through an electric motor with a \"pinion\" gear or small gear to or in mesh with a rotating \"bull\" gear or large gear. All utilities for blowing containers and for mold cooling are carried through the main shaft or the axle from which the wheel rotates about. These utilities include compressed air and water. Sequencing functions necessary to inflate the parison, hold the container prior to discharge and discharge are completed by mechanical actuation to pneumatic valves – resulting in a high degree of repeatability.\nAdvantages & disadvantages.\nVery tight weight and dimensional tolerances can be obtained on wheel equipment, as the parison is captured on both ends. It is pinched in the preceding mold on the leading end, and positioned by the stationary flowhead die on the other end. In shuttle machinery and reciprocating screw machinery multiple parisons are extruded and are free hanging. Because there is always some variation in the parison length on these machines, bottle weight and tolerance consistencies are not as tight as on rotary wheel machinery.\nOther advantages of wheel equipment include:\nDisadvantages:\nApplications.\nThe growth of wheel machinery in the United States was spurred by the conversion of motor oil containers from paperboard cans to plastic bottles, and the conversion of laundry detergent from powder to liquid form. Additional high volume applications have included single-serve juices and drinkable yogurt, condiments, and household cleaning supplies.", "Engineering,_Manufacturing": 1.0000061989, "qwen": "Yes"}
{"id": "173186", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=173186", "title": "Roll-to-roll processing", "text": "In the field of electronic devices, roll-to-roll processing, also known as web processing, reel-to-reel processing or R2R, is the process of creating electronic devices on a roll of flexible plastic, metal foil, or flexible glass. In other fields predating this use, it can refer to any process of applying coating, printing, or performing other processes starting with a roll of a flexible material and re-reeling after the process to create an output roll. These processes, and others such as sheeting, can be grouped together under the general term converting. When the rolls of material have been coated, laminated or printed they can be subsequently slit to their finished size on a slitter rewinder.\nIn electronic devices.\nLarge circuits made with thin-film transistors and other devices can be patterned onto these large substrates, which can be up to a few meters wide and long. Some of the devices can be patterned directly, much like an inkjet printer deposits ink. For most semiconductors, however, the devices must be patterned using photolithography techniques.\nRoll-to-roll processing of large-area electronic devices reduces manufacturing cost. Most notable would be solar cells, which are still prohibitively expensive for most markets due to the high cost per unit area of traditional bulk (mono- or polycrystalline) silicon manufacturing. Other applications could arise which take advantage of the flexible nature of the substrates, such as electronics embedded into clothing, large-area flexible displays, and roll-up portable displays.\nThin-film cells.\nA crucial issue for a roll-to-roll thin-film cell production system is the deposition rate of the microcrystalline layer, and this can be tackled using four approaches:\nIn electrochemical devices.\nThe roll-to-roll processing has been used in the manufacture of electrochemical devices such as batteries, supercapacitors, fuel cells, and water electrolyzers. Here, the roll-to-roll processing is utilized for electrode manufacturing and is the key to reducing manufacturing cost through stable production of electrodes on various film substrates such as metal foils, membranes, diffusion media, and separators.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "1552839", "revid": "1138184620", "url": "https://en.wikipedia.org/wiki?curid=1552839", "title": "Strategic partnership", "text": "A strategic partnership (also see strategic alliance) is a relationship between two commercial enterprises, usually formalized by one or more business contracts. A strategic partnership will usually fall short of a legal partnership entity, agency, or corporate affiliate relationship. Strategic partnerships can take on various forms from shake hand agreements, contractual cooperation's all the way to equity alliances, either the formation of a joint venture or cross-holdings in each other.\nTypically, two companies form a strategic partnership when each possesses one or more business assets or have expertise that will help the other by enhancing their businesses. This can also mean, that one firm is helping the other firm to expand their market to other marketplaces, by helping with some expertise. According to Cohen and Levinthal a considerable in-house expertise which complements the technology activities of its partner is a necessary condition for a successful exploitation of knowledge and technological capabilities outside their boundaries. Strategic partnerships can develop in outsourcing relationships where the parties desire to achieve long-term “win-win” benefits and innovation based on mutually desired outcomes.\nNo matter if a business contract was signed, between the two parties, or not, a trust-based relationship between the partners is indispensable.\nOne common strategic partnership involves one company providing engineering, manufacturing or product development services, partnering with a smaller, entrepreneurial firm or inventor to create a specialized new product. Typically, the larger firm supplies capital, and the necessary product development, marketing, manufacturing, and distribution capabilities, while the smaller firm supplies specialized technical or creative expertise.\nAnother common strategic partnership involves a manufacturer/supplier partnering with a distributor or wholesale consumer. Rather than approach the transactions between the companies as a simple link in the product or service supply chain, the two companies form a closer relationship where they mutually participate in advertising, marketing, branding, product development, and other business functions. As examples, an automotive manufacturer may form strategic partnerships with its parts suppliers, or a music distributor with record labels.\nThe activities of a strategic partnership can also include a shared research & development department between the partners. This requires a higher level of knowledge sharing as well as a higher level of sharing the technological capabilities. But by doing so, the costs and risks of innovation can be spread between the partners.\nStrategic partnerships also have emerged to solve many company business problems. The book \"Vested: How P&G, McDonald’s and Microsoft are Redefining Winning in Business Relationships\" profiles strategic partnerships in large scale business process outsourcing relationships, public-private infrastructure projects, facilities management and supply chain relationships. Contemporary strategic sourcing and procurement processes enable organizations to use performance-based or vested sourcing business models for establishing strategic supplier relationships.\nThere can be many advantages to creating strategic partnerships. As Robert M. Grant states in his book \"Contemporary Strategy Analysis\", \"For complete strategies, as opposed to individual projects, creating option value means positioning the firm such that a wide array of opportunities become available\". Firms taking advantage of strategic partnerships can utilize other company's strengths to make both firms stronger in the long run.\nStrategic partnerships raise questions concerning co-inventorship and other intellectual property ownership, technology transfer, exclusivity, competition, hiring away of employees, rights to business opportunities created in the course of the partnership, splitting of profits and expenses, duration and termination of the relationship, and many other business issues. Another risk of strategic partnerships, especially between manufacturer and key supplier, is the potential forward integration by the key supplier. Also different developments or development plans can lead to a broken strategic partnership. The relationships are often complex as a result, and can be subject to extensive negotiation. Strategic partnerships are also prone to conflict. The University of Tennessee has done significant research into strategic partnerships, especially in the area of strategic outsourcing relationships.", "Engineering,_Manufacturing": 0.9841338992, "qwen": "Yes"}
{"id": "7035221", "revid": "4173550", "url": "https://en.wikipedia.org/wiki?curid=7035221", "title": "Converters (industry)", "text": "Converting companies are companies that specialize in modifying or combining raw materials such as polyesters, adhesives, silicone, adhesive tapes, foams, plastics, felts, rubbers, liners and metals, as well as other materials, to create new products.\nMaterials such as paper, plastic film, foil and cloth often are produced in long, continuous sheets that are rolled up for more convenient handling and transportation. These rolls of material vary significantly in size and weight — ranging from wide and weighing as much as several tons. The converting industry takes these continuous rolls of thin, flat materials — known as webs — threads them through processing machines (such as printing presses, laminating, coating and slitting machines) and converts or changes the web of material into an intermediate form or final product. For example, a converter’s equipment might take a web of plastic film, cut it into lengths, and fuse their edges, thus converting it into plastic bags. This activity is known as web processing.\nProcesses.\nTypical converting processes include coating, laminating and printing. Coating technologies can include hot melt coating, gravure coating, curtain coating and slot-die coating. The most common printing techniques are flexo printing and rotogravure (gravure) printing. Both print processes are suited to high speed roll-to-roll processing.\nMany converting companies will process large diameter, wide rolls of material as this increases the converting efficiency by minimising changes. On completion of the converting process the rolls may be cut into smaller rolls on a slitting machine or a sheeter. These rolls or sheets are then a convenient size for handling on packaging and other machines. Further processes such as collation may occur after sheeting.\nDepending on the specially of the converter, many other processes might be involved. These might include: shearing, die-cutting, laser cutting, heat sealing, laser converting, perforating, Ultrasonic welding, Surface finishing, etc.\nWeb alignment.\nWhen converting from rolls of material, web alignment is an important part of a converting operation as a moving web of material has a tendency to track off course and wander out of alignment during the converting processes. To avoid these problems, engineers have developed a variety of automatic web-guiding systems that assure production accuracy and reduce waste. Web-guiding systems typically are positioned just before a critical stage on a converting machine (for example, just before a print station on a printing press).\nEach type of web guiding system uses a sensor to monitor the web position for lateral tracking, and each has an actuator to shift the running web mechanically back on course whenever the sensor detects movement away from the set path. Actuators may be pneumatic or hydraulic cylinders, or some kind of electromechanical device. Because the web may be fragile — particularly at its edge — non-contact sensors are used. These sensors may be pneumatic, photoelectric, ultrasonic, or infrared. The system’s controls must put the output signals from the sensors in to a form that can drive the actuator. Many controls today are electronic, typically using an amplifier to convert signals from the sensor, then commanding a special servo motor incorporating a lead or ball screw for guiding actuation. The latest web guiding systems have touch screen controls to simplify the setup procedure. Some web guiding systems have been designed specifically for the converting industry.\nServices.\nMany converters specialize in \nNewer technology.\nSome converting companies now incorporate electronics in their finished products. For example, converters producing RFID stock labels must incorporate RFID chips and antenna inlays. The electronic components make up the RFID tag. The tag stores the information about the items that have been tagged. These converters therefore sometimes incorporate volume electronics manufacturing practices including controlling static electricity, electronic manufacturing test and similar processes. Solving some of the issues of inclusion of materials sensitive to external influences has led to more tech companies embracing roll-based manufacturing processes, with particular success in the lithium ion and solar cell manufacturing sectors.\nPaper converting.\nPaper converting can refer to manufacturing processes involving paper as the raw material. This raw material, similar to other converting industries, can be in a roll or sheet form. Paper converting is required for the manufacture of nearly all paper based products, such as magazines, books, newspapers, labels, bags, and general purpose paper products.\nThe process of processing pre-cut cartons or \"blanks\" and folding them into the appropriate shape to become finished packaging containers is known as tray forming or carton erecting. This is a specific example of a type of converting. These machines can create, for example, nacho trays, chinese noodle soup boxes, pizza boxes, french fry trays, hamburger clamshells, etc.", "Engineering,_Manufacturing": 1.0000066757, "qwen": "Yes"}
{"id": "7046816", "revid": "42425010", "url": "https://en.wikipedia.org/wiki?curid=7046816", "title": "Hybrid silicon laser", "text": "A hybrid silicon laser is a semiconductor laser fabricated from both silicon and group III-V semiconductor materials. The hybrid silicon laser was developed to address the lack of a silicon laser to enable fabrication of low-cost, mass-producible silicon optical devices. The hybrid approach takes advantage of the light-emitting properties of III-V semiconductor materials combined with the process maturity of silicon to fabricate electrically driven lasers on a silicon wafer that can be integrated with other silicon photonic devices.\nPhysics.\nA hybrid silicon laser is an optical source that is fabricated from both silicon and group III-V semiconductor materials (e.g. Indium(III) phosphide, Gallium(III) arsenide). It comprises a silicon waveguide fused to an active, light-emitting, III-V epitaxial semiconductor wafer. The III-V epitaxial wafer is designed with different layers such that the active layer can emit light when it is excited either by shining light, e.g. a laser onto it; or by passing electricity through it. The emitted light from the active layer couples into the silicon waveguide due to their close proximity (cavity.\nFabricate.\nThe silicon laser is fabricated by a technique called plasma assisted wafer bonding. Silicon waveguides are first fabricated on a silicon on insulator (SOI) wafer. This SOI wafer and the un-patterned III-V wafer are then exposed to an oxygen plasma before being pressed together at a low (for semiconductor manufacturing) temperature of 300C for 12 hours. This process fuses the two wafers together. The III-V wafer is then etched into mesas to expose electrical layers in the epitaxial structure. Metal contacts are fabricated on these contact layers allowing electric current to flow to the active region. \nSilicon manufacturing and fabrication is widely used in the electronic industry to mass-produce low-cost electronic devices. Silicon photonics uses these same electronic manufacturing technologies to make low-cost integrated optical devices. One issue with using silicon for an optical device is that silicon is a poor light emitter and cannot be used to make an electrically pumped laser. This means that lasers have first to be fabricated on a separate III-V semiconductor wafer before being individually aligned to each silicon device, in a process that is both costly and time-consuming, limiting the total number of lasers that can be used on a silicon photonic circuit. By using this wafer bonding technique many hybrid silicon lasers can be fabricated simultaneously on a silicon wafer, all aligned to the silicon photonic devices.\nUses.\nPotential uses cited in the references below include fabricating many, possibly hundreds of hybrid silicon lasers on a die and using silicon photonics to combine them together to form high bandwidth optical links for personal computers, servers or back planes. These lasers are now fabricated on 300 mm silicon wafers in CMOS foundries in volumes of over one million per year.\nThe low loss of silicon waveguides means these lasers can have very narrow linewidths (LIDARs, optical gyroscopes, and other applications. These lasers can be used to pump nonlinear devices to make optical synthesizers with a stability of 1 part in 1017.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "30843289", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=30843289", "title": "Contingency allowance", "text": "The contingency allowance is the time allocated during planning for unscheduled events. Technical and personal disruptions result in changes in the indirect production costs. The contingency allowance is calculated in special contingency time studies, the results of which yield rates for indirect production costs. The time is usually added to the pure operations time to form a standard time in manufacturing.\nThe concept was developed by Charles Bedaux.", "Engineering,_Manufacturing": 0.9997898936, "qwen": "Yes"}
{"id": "45714189", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=45714189", "title": "Quad in-line package", "text": "In microelectronics, a quad in-line package (QIP or QIL), is an electronic component package with a rectangular housing and four parallel rows of electrical connecting pins. The package may be through-hole mounted to a printed circuit board (PCB) or inserted in a socket. Rockwell used a QIP with 42 leads formed into staggered rows for their PPS-4 microprocessor family introduced in 1973, and other microprocessors and microcontrollers, some with higher lead counts, through the early 1990s.\nThe QIP has the same dimensions as a Dual in-line package (DIP), but the leads on each side are bent into an alternating zigzag configuration so as to fit four lines of solder pads (instead of two with a DIP but similar to Zig-zag in-line package). The QIP design increased the spacing between solder pads without increasing package size, for two reasons:\nSome QIP packaged ICs had added heatsinking tabs, such as the HA1306W.\nIntel and 3M developed the ceramic leadless quad in-line package (QUIP), introduced in 1979, to boost microprocessor density and economy. The ceramic leadless QUIP is not designed for surface-mount use, and requires a socket. It was used by Intel for the iAPX 432 microprocessor chip set, and by Zilog for the Z8-02 external-ROM prototyping version of the Z8 microcontroller.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "45716102", "revid": "4441371", "url": "https://en.wikipedia.org/wiki?curid=45716102", "title": "List of number-one digital tracks of 2007 (Australia)", "text": "The ARIA Digital Track Chart ranks the best-performing digital tracks of Australia. It is published by Australian Recording Industry Association (ARIA), an organisation who collects music data for the weekly ARIA Charts.\nTo be eligible to appear on the chart, the recording must be a single not an EP and only paid downloads counted from downloadable outlets.", "Engineering,_Manufacturing": 0.9999959469, "qwen": "Yes"}
{"id": "45717569", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=45717569", "title": "Reverse costing", "text": "Reverse costing describes the process of disassembling (reverse engineering) a device to identify manufacturing technology and calculate its manufacturing costs through a cost analysis of its parts and the effort required to assemble them.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "845000", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=845000", "title": "Plastic welding", "text": "Plastic welding is welding for semi-finished plastic materials, and is described in ISO 472 as a process of uniting softened surfaces of materials, generally with the aid of heat (except solvent welding). Welding of thermoplastics is accomplished in three sequential stages, namely surface preparation, application of heat and pressure, and cooling. Numerous welding methods have been developed for the joining of semi-finished plastic materials. Based on the mechanism of heat generation at the welding interface, welding methods for thermoplastics can be classified as external and internal heating methods, as shown in Fig 1.\nProduction of a good quality weld does not only depend on the welding methods, but also weldability of base materials. Therefore, the evaluation of weldability is of higher importance than the welding operation (see Rheological weldability) for plastics.\nWelding techniques.\nA number of techniques are used for welding of semi-finished plastic products as given below:\nHot gas welding.\nHot gas welding, also known as \"hot air welding\", is a plastic welding technique using heat. A specially designed heat gun, called a \"hot air welder\", produces a jet of hot air that softens both the parts to be joined and a plastic filler rod, all of which must be of the same or a very similar plastic. (Welding PVC to acrylic is an exception to this rule.)\nHot air/gas welding is a common fabrication technique for manufacturing smaller items such as chemical tanks, water tanks, heat exchangers, and plumbing fittings.\nIn the case of webs and films a filler rod may not be used. Two sheets of plastic are heated via a hot gas (or a heating element) and then rolled together. This is a quick welding process and can be performed continuously.\nWelding rod.\nA plastic welding rod, also known as a \"thermoplastic welding rod\", is a rod with circular or triangular cross-section used to bind two pieces of plastic together. They are available in a wide range of colors to match the base material's color. Spooled plastic welding rod is known as \"spline\".\nAn important aspect of plastic welding rod design and manufacture is the porosity of the material. A high porosity will lead to air bubbles (known as \"voids\") in the rods, which decrease the quality of the welding. The highest quality of plastic welding rods are therefore those with zero porosity, which are called \"voidless\".\nHeat sealing.\nHeat sealing is the process of sealing one thermoplastic to another similar thermoplastic using heat and pressure. The direct contact method of heat sealing utilizes a constantly heated die or sealing bar to apply heat to a specific contact area or path to seal or weld the thermoplastics together. Heat sealing is used for many applications, including heat seal connectors, thermally activated adhesives and film or foil sealing. Common applications for the heat sealing process: Heat seal connectors are used to join LCDs to PCBs in many consumer electronics, as well as in medical and telecommunication devices. Heat sealing of products with thermal adhesives is used to hold clear display screens onto consumer electronic products and for other sealed thermo-plastic assemblies or devices where heat staking or ultrasonic welding is not an option due to part design requirements or other assembly considerations. Heat sealing also is used in the manufacturing of bloodtest film and filter media for the blood, virus and many other test strip devices used in the medical field today. Laminate foils and films often are heat sealed over the top of thermoplastic medical trays, Microtiter (microwell) plates, bottles and containers to seal and/or prevent contamination for medical test devices, sample collection trays and containers used for food products. Medical and the Food Industries manufacturing Bag or flexible containers use heat sealing for either perimeter welding of the plastic material of the bags and/or for sealing ports and tubes into the bags. A variety of heat sealers are available to join thermoplastic materials such as plastic films: Hot bar sealer, Impulse sealer, etc.\nFreehand welding.\nWith freehand welding, the jet of hot air (or inert gas) from the welder is placed on the weld area and the tip of the weld rod at the same time. As the rod softens, it is pushed into the joint and fuses to the parts. This process is slower than most others, but it can be used in almost any situation.\nSpeed tip welding.\nWith speed welding, the plastic welder, similar to a soldering iron in appearance and wattage, is fitted with a feed tube for the plastic weld rod. The speed tip heats the rod and the substrate, while at the same time it presses the molten weld rod into position. A bead of softened plastic is laid into the joint, and the parts and weld rod fuse. With some types of plastic such as polypropylene, the melted welding rod must be \"mixed\" with the semi-melted base material being fabricated or repaired. These welding techniques have been improved over time and have been utilized for over 50 years by professional plastic fabricators and repairers internationally. Speed tip welding method is a much faster welding technique and with practice can be used in tight corners.\nA version of the speed tip \"gun\" is essentially a soldering iron with a broad, flat tip that can be used to melt the weld joint and filler material to create a bond.\nExtrusion welding.\nExtrusion welding allows the application of bigger welds in a single weld pass. It is the preferred technique for joining material over 6 mm thick. Welding rod is drawn into a miniature hand held plastic extruder, plasticized, and forced out of the extruder against the parts being joined, which are softened with a jet of hot air to allow bonding to take place.\nContact welding.\nThis is the same as spot welding except that heat is supplied with thermal conduction of the pincher tips instead of electrical conduction. Two plastic parts are brought together where heated tips pinch them, melting and joining the parts in the process.\nHot plate welding.\nRelated to contact welding, this technique is used to weld larger parts, or parts that have a complex weld joint geometry. The two parts to be welded are placed in the tooling attached to the two opposing platens of a press. A hot plate, with a shape that matches the weld joint geometry of the parts to be welded, is moved in position between the two parts. The two opposing platens move the parts into contact with the hot plate until the heat softens the interfaces to the melting point of the plastic. When this condition is achieved the hot plate is removed, and the parts are pressed together and held until the weld joint cools and re-solidifies to create a permanent bond.\nHot-plate welding equipment is typically controlled pneumatically, hydraulically, or electrically with servo motors.\nThis process is used to weld automotive under hood components, automotive interior trim components, medical filtration devices, consumer appliance components, and other car interior components.\nNon-contact/IR welding.\nSimilar to hot plate welding, non-contact welding uses an infrared heat source to melt the weld interface rather than a hot plate. This method avoids the potential for material sticking to the hot plate, but is more expensive and more difficult to achieve consistent welds, particularly on geometrically complex parts.\nHigh frequency welding.\nHigh Frequency welding, also known as Dielectric Sealing or Radio Frequency (R.F.) Heat Sealing is a very mature technology that has been around since the 1940s. High frequency electromagnetic waves in the range of radio frequencies can heat certain polymers up to soften the plastics for joining. Heated plastics under pressure weld together. Heat is generated within the polymer by the rapid reorientation of some chemical dipoles of the polymer, which means that the heating can be localized, and the process can be continuous.\nOnly certain polymers which contain dipoles can be heated by RF waves, in particular polymers with high loss power. Among these, PVC, polyamides (PA) and acetates are commonly welded with this technology. In practice, two pieces of material are placed on a table press that applies pressure to both surface areas. Dies are used to direct the welding process. When the press comes together, high frequency waves (usually 27.120 MHz) are passed through the small area between the die and the table where the weld takes place. This high frequency (radio frequency) heats the plastic which welds under pressure, taking the shape of the die.\nRF welding is fast and relatively easy to perform, produces a limited degradation of the polymer even welding thick layers, does not create fumes, requires a moderate amount of energy and can produce water-, air-, and bacteria-proof welds. Welding parameters are welding power, (heating and cooling) time and pressure, while temperature is generally not controlled directly. Auxiliary materials can also be used to solve some welding problems. This type of welding is used to connect polymer films used in a variety of industries where a strong consistent leak-proof seal is required. In the fabrics industry, RF is most often used to weld PVC and polyurethane (PU) coated fabrics. Other materials commonly welded using this technology are nylon, PET, PEVA, EVA and some ABS plastics. Exercise caution when welding urethane as it has been known to give off cyanide gasses when melting.\nInduction welding.\nWhen an electrical insulator, like a plastic, is embedded with a material having high electrical conductivity, like metals or carbon fibers, induction welding can be performed. The welding apparatus contains an induction coil that is energised with a radio-frequency electric current. This generates an electromagnetic field that acts on either an electrically conductive or a ferromagnetic workpiece. In an electrically conductive workpiece, the main heating effect is resistive heating, which is due to induced currents called eddy currents. Induction welding of carbon fiber reinforced thermoplastic materials is a technology commonly used in for instance the aerospace industry.\nIn a ferromagnetic workpiece, plastics can be induction-welded by formulating them with metallic or ferromagnetic compounds, called susceptors. These susceptors absorb electromagnetic energy from an induction coil, become hot, and lose their heat energy to the surrounding material by thermal conduction.\nInjection welding.\nInjection welding is similar/identical to extrusion welding, except, using certain tips on the handheld welder, one can insert the tip into plastic defect holes of various sizes and patch them from the inside out. The advantage is that no access is needed to the rear of the defect hole. The alternative is a patch, except that the patch can not be sanded flush with the original surrounding plastic to the same thickness. PE and PP are most suitable for this type of process. The Drader injectiweld is an example of such tool.\nUltrasonic welding.\nIn ultrasonic welding, high frequency (15 kHz to 40 kHz) low amplitude vibration is used to create heat by way of friction between the materials to be joined. The interface of the two parts is specially designed to concentrate the energy for the maximum weld strength. Ultrasonic can be used on almost all plastic material. It is the fastest heat sealing technology available.\nFriction welding.\nIn friction welding, the two parts to be assembled are rubbed together at a lower frequency (typically 100–300 Hz) and higher amplitude (typically ) than ultrasonic welding. The friction caused by the motion combined with the clamping pressure between the two parts creates the heat which begins to melt the contact areas between the two parts. At this point, the plasticized materials begin to form layers that intertwine with one another, which therefore results in a strong weld. At the completion of the vibration motion, the parts remain held together until the weld joint cools and the melted plastic re-solidifies. The friction movement can be linear or orbital, and the joint design of the two parts has to allow this movement.\nSpin welding.\nSpin welding is a particular form of frictional welding. With this process, one component with a round weld joint is held stationary, while a mating component is rotated at high speed and pressed against the stationary component. The rotational friction between the two components generates heat. Once the joining surfaces reach a semi-molten state, the spinning component is stopped abruptly. Force on the two components is maintained until the weld joint cools and re-solidifies. This is a common way of producing low- and medium-duty plastic wheels, e.g., for toys, shopping carts, recycling bins, etc. This process is also used to weld various port openings into automotive under hood components.\nLaser welding.\nThis technique requires one part to be transmissive to a laser beam and either the other part absorptive or a coating at the interface to be absorptive to the beam. The two parts are put under pressure while the laser beam moves along the joining line. The beam passes through the first part and is absorbed by the other one or the coating to generate enough heat to soften the interface creating a permanent weld.\nSemiconductor diode lasers are typically used in plastic welding. Wavelengths in the range of 808 nm to 980 nm can be used to join various plastic material combinations. Power levels from less than 1W to 100W are needed depending on the materials, thickness and desired process speed.\nDiode laser systems have the following advantages in joining of plastic materials:\nRequirements for high strength joints include adequate transmission through upper layer, absorption by lower layer, materials compatibility (wetting), good joint design (clamping pressure, joint area), and lower power density.\nSome materials that can be joined include polypropylene, polycarbonate, acrylic, nylon, and ABS.\nSpecific applications include sealing, welding, or joining of: catheter bags, medical containers, automobile remote control keys, heart pacemaker casings, syringe tamper evident joints, headlight or tail-light assemblies, pump housings, and cellular phone parts.\nTransparent laser plastic welding.\nNew fiber laser technology allows for the output of longer laser wavelengths, with the best results typically around 2,000 nm, significantly longer than the average 808 nm to 1064 nm diode laser used for traditional laser plastic welding. Because these longer wavelengths are more readily absorbed by thermoplastics than the infrared radiation of traditional plastic welding, it is possible to weld two clear polymers without any colorants or absorbing additives. Common applications will mostly fall in the medical industry for devices like catheters and microfluidic devices. The heavy use of transparent plastics, especially flexible polymers like TPU, TPE and PVC, in the medical device industry makes transparent laser welding a natural fit. Also, the process requires no laser absorbing additives or colorants making testing and meeting biocompatibility requirements significantly easier.\nSolvent welding.\nIn solvent welding, a solvent is applied which can temporarily dissolve the polymer at room temperature. When this occurs, the polymer chains are free to move in the liquid and can mingle with other similarly dissolved chains in the other component. Given sufficient time, the solvent will permeate through the polymer and out into the environment, so that the chains lose their mobility. This leaves a solid mass of entangled polymer chains which constitutes a solvent weld.\nThis technique is commonly used for connecting PVC and ABS pipe, as in household plumbing. The \"gluing\" together of plastic (polycarbonate, polystyrene or ABS) models is also a solvent welding process.\nDichloromethane (methylene chloride) can solvent weld polycarbonate and polymethylmethacrylate. It is a primary ingredient in some solvent cements. ABS plastic is typically welded with Acetone based solvents which are often sold as paint thinners or in smaller containers as nail polish remover.\nSolvent welding is a common method in plastics fabrication and used by manufacturers of in-store displays, brochure holders, presentation cases and dust covers. Another popular use of solvents in the hobby segment is model building from injection molded kits for scale models of aircraft, ships and cars which predominantly use Polystyrene plastic.\nTesting of plastic welds.\nIn order to test plastic welds, there are several requirements for both the inspector as well as the test method. Furthermore, there are two different types of testing weld quality. These two types are destructive and non-destructive testing. Destructive testing serves to qualify and quantify the weld joint whereas nondestructive testing serves to identify anomalies, discontinuities, cracks, and/or crevices. As the names of these two tests implies, destructive testing will destroy the part that is being tested while nondestructive testing enables the test piece to be used afterwards. There are several methods available in each of these types. This section outlines some requirements of testing plastic welds as well as the different types of destructive and non-destructive methods that are applicable to plastic welding and go over some of the advantages and disadvantages.\nTesting requirements.\nSome standards like the American Welding Society (AWS) require the individuals who are conducting the inspection or test to have a certain level of qualification. For example, AWS G1.6 is the Specification for the Qualification of Plastic Welding Inspectors for Hot Gas, Hot Gas Extrusion, and Heated Tool Butt Thermoplastic Welds. This particular standard dictates that in order to inspect the plastic welds, the inspector needs one of 3 different qualification levels. These levels are the Associate Plastics Welding Inspector (APWI), Plastics Welding Inspector (PWI), and Senior Plastics Welding Inspector (SPWI). Each of these levels have different responsibilities. For example, the APWI has to have direct supervision of a PWI or SPWI in order to conduct the inspection or prepare a report. These three different levels of certification also have different capability requirements, education requirements, and examination requirements. Additionally, they must be able to maintain that qualification every 3 years.\nDestructive testing.\nBend testing.\nThe bend test uses a ram to bend the test coupon to a desired degree. This test setup is shown in Figure 2. \nA list of the minimum bend angles and ram displacements for different plastic materials can be found in the DVS Standards, DVS2203-1 and DVS2203-5. Some of the ram speeds, bend angle, and displacement information from DVS2203-1 are shown in Table 1 and Table 2.\nSome of the main advantages of the bend test are it provides qualitative data for tensile, compressive, and shear strain. These results typically lead to a higher confidence level in the quality of the weld joint and process. In contrast, some of the disadvantages are it requires multiple test pieces. It is typically recommended to use a minimum of 6 different test samples. Another disadvantage is that it does not provide specific values for evaluating the joint design. Moreover, large amounts of effort may need to go into preparing the part for testing. This could cause an increase in cost and schedule depending on the complexity of the part. Lastly, like all destructive tests, the part and/or weld seam is destroyed and cannot be used.\nTensile testing.\nWhen conducting the tensile test, a test piece is pulled until it breaks. This test is quantitative and will provide the ultimate tensile strength, strain, as well as the energy to failure if it has extensometers attached to the sample. Additionally, the results from a tensile test cannot be transferable to that of a creep test. The rate at which the specimen is pulled depends on the material. Additionally, the shape of the specimen is also critical. DVS2203-5 and AWS G1.6 are great sources for providing these details. Examples of the shapes are shown in Figure 3 through Figure 5. Additionally, the testing speed per material is shown in Table 3.\nOne advantage of the tensile test is that it provides quantitative data of the weld for both weld seam and the base material. Additionally, the tensile test is easy to conduct. A major disadvantage of this testing is the amount of preparation required to conduct the test. Another disadvantage is that it does not provide the long-term weld performance. Additionally, since this is also a type of destructive test, the part is destroyed in order to collect this data.\nImpact Testing.\nAlso known as the Tensile Impact Test, the Impact Test uses a specimen that is clamped into a pendulum. The test specimen looks like the one shown in Figure 4. The pendulum swings down and strikes the specimen against an anvil breaking the specimen. This test enables the impact energy to be determined for the weld seam and base material. Additionally, the permanent fracture elongation can be calculated by measuring the post-test specimen length. The main advantage of this test is that quantitative data is obtained. Another advantage is that it is easy to set up. The disadvantages are that it too can have a great deal of preparation in order to conduct this test. Also, like the tensile test, there is not a long term weld performance determined, and the part is destroyed.\nCreep test.\nThere are two types of creep tests, the Tensile Creep Test and the Creep Rupture Test. Both creep tests look at the long-term weld performance of the test specimen. These tests are typically conducted in a medium at a constant temperature and constant stress. This test requires a minimum of 6 specimens in order to obtain enough data to conduct a statistical analysis. This test is advantageous in that it provides quantitative data on the long-term weld performance; however, it has its disadvantages as well. There is a lot effort that needs to go into preparing the samples and recording where exactly the specimen came from and the removal method used. This is critical because how the specimen is removed from the host part can greatly influence the test results. Also, there has to be strict control of the test environment. A deviation in the medium's temperature can cause the creep rupture time to vary drastically. In some cases, a temperature change of 1 degree Celsius affected the creep rupture time by 13%. Lastly, this test is again a destructive test, so the host part will be destroyed by conducting this type of test.\nNon-destructive testing.\nVisual examination.\nVisual inspection, just like the name implies, is a visual investigation of the weldment. The inspector is typically looking for visual indications such as discolorations, weld defects, discontinuities, porosity, notches, scratches, etc. Typically visual inspection is broken down into different categories or groups for the qualifying inspection criteria. These groupings may vary among standards and each group has a certain level of imperfections that they consider acceptable. There are 5 tables and a chart found in DVS Standard DVS2202-1 that show different types of defects found by visual examination and their permissible acceptance criteria.\nVisual inspection is very advantageous in the fact that it is quick, easy, inexpensive, and requires very simple tools and gauges in order to conduct. Because it is so quick, it is typically required to have a weld pass visual inspection prior to being able to have any additional nondestructive test conducted to the specimen. In contrast, the inspection needs to be completed by someone who has a lot of experience and skill. Additionally, this type of test will not give any data into the quality of the weld seam. Because of the low cost, if a part is suspected to have issues, follow on testing can be conducted without much initial investment.\nX-ray testing.\nX-ray testing of plastics is similar to that of metal weldments, but uses much lower radiation intensity due to the plastics having a lower density than metals. The x-ray testing is used to find imperfections that are below the surface. These imperfections include porosity, solid inclusions, voids, crazes, etc. The x-ray transmits radiation through the tested object onto a film or camera. This film or camera will produce an image. The varying densities of the object will show up as different shades in the image thus showing where the defects are located. One of the advantages of X-ray is that it provides a way to quickly show the flaws both on the surface and inside the weld joint. Additionally, the X-ray can be used on a wide range of materials. They can be used to create a record for the future. One of the disadvantages of X-ray is that it is costly and labor-intensive. Another is that it cannot be used in the evaluation of the weld seam quality or optimize the process parameters. Additionally, if the discontinuity is not aligned properly with the radiation beam, it can be difficult to detect. A fourth disadvantage is that access to both sides of the component being measured is required. Lastly, it presents a health risk due to the radiation that is transmitted during the X-ray process.\nUltrasonic testing.\nUltrasonic testing utilizes high frequency sound waves passing through the weld. The waves are reflected or refracted if they hit an indication. The reflected or refracted wave will have a different amount of time it requires to travel from the transmitter to the receiver than it will if an indication was not present. This change in time is how the flaws are detected. The first advantage that ultrasonic testing provides is that it allows for a relatively quick detection of the flaws inside of the weld joint. This test method also can detect flaws deep inside the part. Additionally, it can be conducted with access from only one side of the part. In contrast, there are several disadvantages of using ultrasonic testing. The first is that it cannot be used to optimize the process parameters or evaluate the seam quality of the weld. Secondly, it is costly and labor-intensive. It also requires experienced technicians to conduct the test. Lastly, there are material limitations with plastics due to transmission limitations of the ultrasonic waves through some of the plastics. The image in Figure 6 shows an example of ultrasonic testing.\nHigh voltage leak testing.\nHigh voltage testing is also known as spark testing. This type of testing utilizes electrically conductive medium to coat the weld. After the weld is coated, the weld is exposed to a high voltage probe. This test shows an indication of a leak in the weld when an arc is observed through the weld. This type of testing is advantageous in the fact that it allows for quick detection of the flaws inside the weld joint and that you only have to have access to one side of the weld. One disadvantage with this type of testing is that there is not a way to evaluate the weld seam quality. Additionally, the weld has to be coated with conductive material.\nLeak-tightness testing.\nLeak-Tightness Testing or Leak Testing utilizes either liquid or gas to pressurize a part. This type of testing is typically conducted on tubes, containers, and vessels. Another way to leak-test one of these structures is to apply a vacuum to it. One of the advantages is that it is a quick simple way for the weld flaw to be detected. Additionally, it can be used on multiple materials and part shapes. On the other hand, it has a few disadvantages. Firstly, there is not a way to evaluate the weld seam quality. Secondly, it has an explosion hazard associated with it if over pressurization occurs during testing. Last, it is limited to tubular structures.,", "Engineering,_Manufacturing": 1.0000001192, "qwen": "Yes"}
{"id": "52981678", "revid": "45718847", "url": "https://en.wikipedia.org/wiki?curid=52981678", "title": "Direct chill casting", "text": "Direct Chill casting is a method for the fabrication of cylindrical or rectangular solid ingots from non-ferrous metals, especially Aluminum, Copper, Magnesium and their alloys. The original ingots are usually further processed by other methods (rolling, forging, etc.). More than half of global aluminum production uses the Direct Chill casting process.\nDirect Chill casting operates by pouring liquid metal continuously into a short mold (7.5–15 cm deep) that is open at the bottom. Only an outer layer of metal solidifies within the water-cooled mold. After leaving the closed mold at its bottom (e.g. with 5–15 cm/min), water is directly sprayed on the new ingot, continuing the solidification until complete. Only about 20% of the heat of the molten metal is removed through the mold wall, the secondary cooling (Direct Chill) contributing the majority of cooling. Typically the process is started with a starter-dummy block at the bottom of the mold, and runs until the maximum length possible in the machine is reached (up to 10 m).\nThe casting method reduces the internal stress in the cooled material by allowing contractions on all sides, as opposed to only on the top of the ingot in a traditional trough mold.", "Engineering,_Manufacturing": 0.9979072809, "qwen": "Yes"}
{"id": "31817651", "revid": "943732410", "url": "https://en.wikipedia.org/wiki?curid=31817651", "title": "Magnetic field-assisted finishing", "text": "Magnetic field-assisted finishing, sometimes called magnetic abrasive finishing, is a surface finishing technique in which a magnetic field is used to force abrasive particles against the target surface. As such, finishing of conventionally inaccessible surfaces (e.g., the inside surface of a long curved pipe) is possible. Magnetic field-assisted finishing (MAF) processes have been developed for a wide variety of applications including the manufacturing of medical components, fluid systems, optics, dies and molds, electronic components, microelectromechanical systems, and mechanical components.\nHistory.\nMAF was initially developed as a machining process in the US in the 1930s, with the first patent in the 1940s. University research in the Soviet Union, Bulgaria, Germany, Poland, and US began in the 1960s with practical usage appearing by the 1980s and 1990s. The growth of the semiconductor, aerospace, and optics industries have resulted in the continued development of better methods for attaining high form accuracy and surface integrity.\nTheory.\nMagnetic Assisted Finishing or \"MAF\" is essentially the manipulation of a homogeneous mixture of magnetic particles and abrasive particles with a magnetic field to impart a machining force on a workpiece. Relative motion between the particle mixture and the workpiece surface result in material removal. Since MAF does not require direct contact with the tool, the particles can be introduced into areas which are hard to reach by conventional techniques. Additionally careful selection of magnetic particles and abrasive particles give rise to surface texture and roughness control that was previously impossible especially for hard to access areas.\nField sources.\nThe magnetic field source in MAF is typically an electromagnet or a rare earth permanent magnet. A permanent magnet offers high energy density, lack of overheating resulting in a constant flux density, low cost, ease of integration into existing CNC equipment, and simplicity. Some applications require adjustment of the flux density during finishing, or require a switching magnetic field, which is only attainable with an electromagnet since the magnetic field in a permanent magnet cannot simply be switched off.\nEquipment.\nRelative motion between the magnetic/abrasive particle mixture and the workpiece is essential for material removal. There are several options for achieving the necessary motion. A common setup is the rotation of the magnetic pole tip. This is done by either rotating the entire permanent magnet setup or by rotating only the steel pole. Another method which is commonly utilized in internal finishing is the rotation of the workpiece, this is unfortunately limited to axial symmetric workpieces. In addition to rotational motion there is oscillatory and vibrational configurations that are applicable.\nForce on a particle.\nStart with the common expression for force on a magnetic dipole moment in a magnetic field,\nFrom here, make the assumption that the moment of the magnetic particle is co-linear with the applied field. This is a reasonable assumption given the small size and high susceptibility of the magnetic particles. So the equation becomes, \nUsing the following identities to obtain a more usable equation to describe the force experienced by a single magnetic particle,\nSubstituting the above definitions into the magnetic force equation yields,\nwhere,\nBrush.\nBrush formation.\nIt is theorized that the formation of the brush is governed by three driving energies. The first energy Wm is the magnetization energy between particles which result in the formation of magnetic chains of particles. The next energy is known as Repulsion energy Wf this is the separation of adjacent chains of material particles driven by the Faraday effect, this is the reason why the chains do not immediately mix into one giant chain. Finally the third energy is called the Tension energy Wt, this refers to the energy required to counteract the curved magnetic chains. \nForces applied by brush.\nThe force applied to the surface by a magnetic particle in the magnetic brush can be divided into two components. The normal force and the tangential force.\nThe normal force at the surface applied by a magnetic particle can be defined as a function of area S and magnetic field B in the following expression:[3]\nThe tangential force of the brush can be defined as a change in energy of the brush due to an obstruction. Since the magnetic particle prefer to be in the lowest energy state, an increase in energy due to deviation from the magnetic flux lines can result in a horizontal \"restoring\" force which is acted on the surface of the workpiece. This restoring force can be defined as:\nMaterial removal.\nThe combination of tangential force and normal forces exerted by the brush onto the workpiece is theorized to remove material from the top peaks of the surface asperities. This process is repeated as the contact between the brush and the surface continues during the finishing operation. Over time the surface roughness of the workpiece surface reaches a minimum value, this is due to the physical limitations of the current finishing setup. Specifically the selection of iron particles and abrasive particles dictates the minimum surface roughness that can be achieved. As the surface roughness decreases smaller abrasive particles are necessary to continue material removal.\nMAF is capable of achieving roughness values ranging from 200 μm Ra down to 1 nm Ra with ease, demonstrating the degree of customization available to a MAF setup. The particle sizes for the magnetic particles in the brush dictate the finishing force which is governed by the magnetic force on a particle equation. however increasing particle size has adverse effects such as the inability to hold small abrasives and the presence of air gaps as a result of a larger packing factor. In order to alleviate these problems it is common practice to mix the magnetic particles with both large and smaller particles to \"fill\" the \"holes\" of the brush, the small particles effectively coat the larger particles within the particle chain. Close control of the surface texture and roughness can be manipulated through the selection of the right abrasive size and oscillation speed and spindle rpm. Generally speaking the faster the motion of the brush the more dense the finishing marks on the surface and the higher the surface roughness.\nTypes.\nMAF can be divided into three main categories, each defined by the type of magnetic particles utilized in the finishing operation. Each type has its specific niche that it may fulfill better than its counterparts therefore knowing the application of the process is key to selecting the proper finishing operation. The different MAF processes are listed in increasing surface roughness resolution while decreasing in applied force. This is primarily due to the reduction in iron particle size from one type of finishing to the next. These processes are just general terms and examples for some MAF setups, it is import to note that each of these process' have different variations to increase to applicability to other workpieces.\nMagnetic abrasive finishing.\nMagnetic Abrasive Finishing refers to using 1 μm - 2 mm iron particles mixed with an abrasive to apply the machining force through manipulation of the particles with a magnetic field. The magnetic particle and abrasive mixture is commonly referred to the \"magnetic brush\" because it appears and behaves similar to a wire brush. Unlike a conventional brush the magnetic chains of particles are flexible and will conform around any geometry. As the displacement of the brush increases beyond the flexibility of the bush the magnetic bristles are able to break and reform further increasing the flexibility and versatility of this finishing process. Therefore, this specific variety of MAF is aimed towards finishing of the free form external surfaces such as airfoils or prosthesis. However it can also easily be applicable to internal finishing processes and is especially effective at finishing the internal surfaces of workpieces that are difficult to access otherwise such as capillary tubes and other small gauge needles. The main difference between internal and external finishing operations is the location of the brush and the workpiece however the application of force is essentially the same hence the material removal mechanism is identical in both cases. One key parameter that the user needs to be aware of is the proper completion of the magnetic circuit to ensure the magnetic flux uniformly permeates through the workpiece at the desired finishing location. The addition of an oil based lubricant, the magnetic brush can also be considered a magnetorheological fluid.\nMagnetorheological finishing.\nMagnetorheological finishing or \"MRF\" uses the shearing of a viscous mixture of micron sized iron particles, abrasives, and oil to impart a machining force or pressure onto the workpiece surface. This magnetic particle mixture is commonly referred to a ribbon and is extremely viscous in the presence of a magnetic field, the increased viscosity and different fluid properties are similar to those of a Bingham fluid rather than a Newtonian fluid. In a typical MRF finishing setup the MRF fluid is pumped onto a rotating wheel which is connected to an electromagnet. When the electromagnet is activated the fluid transitions to a more viscous state, the workpiece is then pressed onto the fluid resulting a shearing of the fluid which results in material removal at the interface between the workpiece and the MRF. One of the characteristics of a Bingham fluid is as speed increases the force required to shear proportionally increases therefore an increased wheel rotational rate results in an increased machining force when sheared. This particular setup is ideal for large free form nonmagnetic workpieces such as glass optics. It is also commonly applied to large nonmagnetic workpieces where the thickness of the work results in difficulty in getting the magnetic field to permeate effectively at the desired location hence this setup does not rely on the careful design of the magnetic circuit.\nApplications.\nSub-nanometer scale polishing\nMagnetic fluid finishing.\nIn magnetic fluid finishing a solution of ferrofluid and abrasive particles are used as the magnetic particle mixture. Typically this is applicable for applications where even the other types of MAF are unable to access or when a less viscous medium is desired. One example application of magnetic fluid finishing is silicon micropore optics, in the case of this particular optic the side walls are to be finished to <1.0 nm rms for x-ray reflection. The pores are 5μmx20μmx300μm which makes it virtually impossible to access with any conventional technique. The magnetic particle and abrasive solution is placed in an alternating and switching magnetic field to encourage fluid flow from one side of the optic to the other side. This flow results in material removal of the sidewalls through the momentum of the fluid and shearing of the side walls with the abrasives. Another application is in the finishing of ceramic bearing balls. This is also known as magnetic float polishing and employs a magnetic fluid with a magnetic \"float\" to ensure an even pressure distribution on the sphere surface during rotation. This results in a uniform application of finishing force onto the workpiece surface.", "Engineering,_Manufacturing": 1.0000040531, "qwen": "Yes"}
{"id": "31843696", "revid": "39411839", "url": "https://en.wikipedia.org/wiki?curid=31843696", "title": "Aluminium foam sandwich", "text": "Aluminium foam sandwich (AFS) is a sandwich panel product which is made of two metallic dense face sheets and a metal foam core made of an aluminium alloy. AFS is an engineering structural material owing to its stiffness-to-mass ratio and energy absorption capacity ideal for application such as the shell of a high-speed train.\nProduction and materials.\nIn terms of the bonding between face sheets and foam core the processing of AFS is categorised into two ways – ex-situ and in-situ bonding.\nEx-situ bonded AFS.\nEx-situ bonding is achieved by gluing face sheets with an aluminium foam by adhesive bonding, brazing or diffusion bonding. Foams used in this method are either closed-cell or open-cell. When a closed-cell foam is used then it is produced from aluminium alloys either by liquid metal route (e.g. Alporas, Cymat) or by powder metallurgy route. Open-cell foam core is made of aluminium and other metals as well. Face sheets are chosen from a variety of aluminium alloy, and other metals such as steel.\nIn-situ bonded AFS.\nFor in-situ bonded face sheets the core is closed-cell foam. The goal of in-situ bonding is to create a metallic bonding between the foam core and face sheets. This is achieved in three ways. A foamable precursor is expanded between two face sheets. When the liquid foam comes in contact with the solid face sheets a metallic bond is established. This is difficult to realize as the oxidation of both aluminium face sheets and foam prevent forming a sound bonding. There is also a risk of melting the face sheets. This procedure is successful when steel is used as face sheets instead of aluminium, while the foam core is aluminium.\nAnother strategy is to rapidly solidify the surface of a foamable molten metal before it can foam into a dense skin while the interior of the metal evolves to a foam structure. This process yields in an integral-type foam structure. Integral foam sandwich is made of aluminium alloys (AlCu4, AlSi9Cu3) and magnesium alloys (AZ91, AM60). In this process the material for the core and face sheet is the same.\nThe third way to achieve in-situ bonding consists of compaction of metal powders together with face sheets. This sandwich-compact assembly goes through several rolling steps to attain desired precursor and face sheet thickness. After which this three-layer composite is heated to transform the core layer into foam. The melting point of the face sheet material is above the melting point of the foamable precursor material. The precursor composition is usually Al-Si, Al-Si-Cu or Al-Si-Mg alloys while the face sheets are 3xxx, 5xxx and 6xxx series aluminium alloys.\nPre- and post-processing of AFS panels.\nIt is possible to manufacture a complicated 3D shape from in-situ bonded AFS. In case of the second type, i.e. integral foam moulding, the desired geometry of the foamed part is achieved by designing the mould inside which the foam is cast.\nIn the case of the third type the three-layer composite precursor is reshaped prior to foaming. Heating of such part yields in a 3D shaped foam part. The three-layer composite AFS panels are also reshaped after foaming by forging. If an AFS is made of heat treatable alloys, the strength is further enhanced by age hardening. In order to join two AFS parts or to join an AFS part with a metallic part several joining technologies are employed, such as laser welding, TIG welding, MIG welding, riveting, etc.", "Engineering,_Manufacturing": 0.9999983311, "qwen": "Yes"}
{"id": "2398885", "revid": "7770027", "url": "https://en.wikipedia.org/wiki?curid=2398885", "title": "Slotting fee", "text": "A slotting fee, slotting allowance, pay-to-stay, or fixed trade spending is a fee charged to produce companies or manufacturers by supermarket distributors (retailers) in order to have their product placed on their shelves or within their supply chain. The fee varies greatly depending on the product, manufacturer, and market conditions. For a new product, the initial slotting fee may be approximately US$25,000 per item in a regional cluster of stores, but may be as high as US$250,000 in high-demand markets.\nIn addition to slotting fees, retailers may also charge promotional, advertising and stocking fees. According to a Federal Trade Commission study, the practice is \"widespread\" in the supermarket industry. Many grocers earn more profit from agreeing to carry a manufacturer's product than they do from actually selling the product to retail consumers. Fees may serve to efficiently allocate scarce retail shelf space, help balance the risk of new product failure between manufacturers and retailers, help manufacturers signal private information about potential success of new products, and serve to widen retail distribution for manufacturers by mitigating retail competition. For vendors, slotting fees may be a move by the grocery industry to profit at their suppliers' expense.\nSome companies argue that slotting fees are unethical as they create a barrier to entry for smaller businesses that do not have the cash flow to compete with large companies. The use of slotting fees can, in some instances, lead to abuse by retailers such as in the case where a bakery firm was asked for a six figure fee to carry its items for a specific period with no guarantee its products would be carried in future periods.\nThe same practice is also common in major bookstore chains in the US, dating from as far back as the mid-nineties.", "Engineering,_Manufacturing": 0.9976331592, "qwen": "Yes"}
{"id": "7985341", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=7985341", "title": "Jakob Bengel", "text": "Jakob Bengel was a chain and costume jewelry factory, founded by Jakob Bengel in 1873 in Idar-Oberstein, Germany.\nUntil 1920, the company specialized in the production of watch chains and chatelaines (pendants for pocket watches). In the 1920s and 1930s, it became one of the leading manufacturers of fashion jewelry in the Art Deco style.\nIt was during the Bauhaus and Art Deco period that designers were looking to obtain new materials and inspiration to produce costume jewelry.\nInspired by French Avant-Garde and other fashion trendsetters such as Coco Chanel, Bengel started to produce experimental jewelry. The pieces, catalogued 1924–1939, combined brass and chrome with geometric shapes of colored galalith.", "Engineering,_Manufacturing": 0.9924099445, "qwen": "Yes"}
{"id": "7997999", "revid": "29625245", "url": "https://en.wikipedia.org/wiki?curid=7997999", "title": "Sheet moulding compound", "text": "Sheet moulding compound (SMC) or sheet moulding composite is a ready to mould glass-fibre reinforced polyester material primarily used in compression moulding. The sheet is provided in rolls weighing up to 1000 kg. Alternatively the resin and related materials may be mixed on site when a producer wants greater control over the chemistry and filler.\nSMC is both a process and reinforced composite material. This is manufactured by dispersing long strands (usually >1”) of chopped fiber, commonly glass fibers or carbon fibers on a bath of thermoset resin (typically polyester resin, vinyl ester resin or epoxy resin). The longer fibers in SMC result in better strength properties than standard bulk moulding compound (BMC) products. Typical applications include demanding electrical applications, corrosion resistant needs, structural components at low cost, automotive, and transit. \nProcess.\nPaste reservoir dispenses a measured amount of specified resin paste onto a plastic carrier film. This carrier film passes underneath a chopper which cuts the fibers onto the surface. Once these have drifted through the depth of resin paste, another sheet is added on top which sandwiches the glass. The sheets are compacted and then enter onto a take-up roll, which is used to store the product whilst it matures. The carrier film is then later removed and the material is cut into charges. Depending on what shape is required determines the shape of the charge and steel die which it is then added to. Heat and pressure act on the charge and once fully cured, this is then removed from the mould as the finished product. Fillers both reduce weight and change the physical properties, typically adding strength. Production challenges include wetting the filler, which could consist of glass microspheres or aligned fibers rather than random chopped fibers; adjusting die temperature and pressure to provide the proper geometry; and adjusting chemistry to end use.\nAdvantages.\nCompared to similar methods, SMC benefits from a very high volume production ability, excellent part reproducibility, it is cost effective as low labor requirements per production level is very good and industry scrap is reduced substantially. Weight reduction, due to lower dimensional requirements and because of the ability to consolidate many parts into one, is also advantageous. The level of flexibility also exceeds many counterpart processes.\nPhysical properties.\nProperties vary depending upon filler and resin types, with compounds using aligned fibers (especially long fibers) being subject to greater anisotropy. Typical ranges are listed below.", "Engineering,_Manufacturing": 1.000007987, "qwen": "Yes"}
{"id": "3309826", "revid": "1166879753", "url": "https://en.wikipedia.org/wiki?curid=3309826", "title": "Hyundai Mobis", "text": "Hyundai Mobis (short for \"Mobile\" and \"System\") is a public South Korean car parts company. Founded as Hyundai Precision & Industries Corporation  in 1977, the company forms the \"parts and service\" arm for the South Korean automakers Hyundai Motor Company, Genesis Motors and Kia Motors. As of 2014, it was the \"world's No. 6 automotive supplier.\"\nHistory.\nHeadquartered in Seoul, South Korea, it was founded on June 25, 1977 as Hyundai Precision & Industries Corporation. In 2000, the company changed its name to Hyundai Mobis. The company forms the \"parts and service\" arm for the South Korean automakers Hyundai Motor Company, Genesis Motors and Kia Motors. In 2013, the company had revenue of US$ 33 billion. As of 2014, it was \"the world's No. 6 automotive supplier\" in \"Bloomberg\".\nIn June 2023, the company ranked #464 on the Forbes Global 2000, with a market cap of US $15.14 billion.\n In 2015, it had revenues of $32.11 billion.\nProducts.\nThe company offers chassis, cockpit, and front-end modules; safety products, including airbags; headlights; anti-lock brake system and electronic stability control products; steering parts; multimedia systems; Kia Connect systems; injection-molded plastic parts, such as instrument panels, carriers, and bumpers; and steel wheel rims and decks. It also supplies after-sales service parts for vehicles. Concentrating its resources on A/S parts sales, module parts manufacture and parts export, Hyundai MOBIS has firmly established its position as the leading auto parts specialist company.\nCar production.\nIn the 1990s, Hyundai Precision produced the Hyundai Galloper and Santamo cars at the Ulsan plant next to Giant Hyundai motor complex. Hyundai motor Ulsan complex was at that time the world's single largest motor plant of 1.5 million units production capacity.\nI.E 5 assembly plant of 30,000 car production annual capacity since 2000s, but production shifted to the Hyundai Motor Company in 1999.", "Engineering,_Manufacturing": 0.9998249412, "qwen": "Yes"}
{"id": "38235410", "revid": "125972", "url": "https://en.wikipedia.org/wiki?curid=38235410", "title": "Rotary union", "text": "A rotary union is a union that allows for rotation of the united parts. It is thus a device that provides a seal between a stationary supply passage (such as pipe or tubing) and a rotating part (such as a drum, cylinder, or spindle) to permit the flow of a fluid into and/or out of the rotating part. Fluids typically used with rotary joints and rotating unions include various heat transfer media and fluid power media such as steam, water, thermal oil, hydraulic fluid, and coolants.\nA rotary union is sometimes referred to as a rotating union, rotary valve, swivel union, rotorseal, rotary couplings, rotary joint, rotating joints, hydraulic coupling, pneumatic rotary union, through bore rotary union, air rotary union, electrical rotary union, or vacuum rotary union\nFunction.\nA rotary union will lock onto an input valve while rotating to meet an outlet. During this time the liquid and/or gas will flow into the rotary union from its source and will be held within the device during its movement. This liquid and/or gas will leave the union when the valve openings meet during rotation, and more liquid and/or gas will flow into the union again for the next rotation.\nOften functioning under high pressure and constant movement, a rotary union is designed to rotate around an axis. A rotary union's design can be altered to change this or to increase the psi or rpm it needs to withstand as well as the number of valves required.\nComposition.\nWhile rotary unions come in many shapes, sizes, and configurations, they always have the same four basic components: a housing unit, a shaft, a bearing (mechanical) (or bearings), and a seal. Rotary unions typically are constructed from stainless steel to resist rust and corrosion, but many other metals can be involved, like aluminum.\nHousing.\nThe housing is the component that holds all of the other elements of the rotary union together. The housing has an inlet port, which is a threaded port to which the hose supplying the medium will be attached. The rotary union may also have an outlet port, if the same joint is being used both to supply fluid to a roll and to remove fluid from the roll. In smaller rotary unions the housing is stationary. In larger rotary unions the housing is usually bolted to the drum or roll using a flange. In these cases the housing rotates at the same speed as the drum\nShaft.\nThe shaft is the component that carries the medium through the rotary union into the drum or roll. In many cases the shaft will turn with the drum or roll. In some cases, like in larger flanged rotary unions, the shaft may be stationary while the housing rotates. The bearings and seal are typically assembled around the shaft.\nBearing.\nThe second most important part of the rotary union is the bearing. A rotary union may have only one bearing, but multiple bearing are much more common. Roller bearings; such as ball bearings and tapered roller bearings; or non-roller bearings, like graphite bearings and bronze bushings, may be used in a rotary union. The bearings are always used to allow a part of the joint, either the shaft or the housing, to rotate\nMechanical seal.\nThe heart of the rotary union is the seal. The seal prevents the medium from leaking outside the rotary union while in operation. Seal types can vary from pusher-type end face mechanical seal, non-pusher type end face mechanical seal, lip seals, and o-ring seals. Most rotary unions have more than one seal.\nTypes of rotary unions.\nMany rotary unions incorporate multiple ports, some of which are designed to handle different types of material simultaneously. \nA rotary union with a straight port transfers the substance directly through the rotary union. Other designs include an elbow port, which causes the material to flow out at an angle, and multiple ports. A multiple port rotary union looks like a perforated cylinder. At the end of the cylinder is a threaded screw with a seal or seals that lock on to it. The material being transferred flows into the cylinder and out of the input holes. \nIn the case of a rotary union with multiple inputs, chambers separated by seals keep the materials from inadvertently mixing. This type of rotary union is often used in the manufacture of plastics and other petroleum products, for which multiple inputs may need to be streamlined, but kept separate.\nUses.\nMany assembly lines incorporate multiple rotary unions, because they are highly versatile and take up less space than other devices designed for a similar purpose. Rotary unions also appear in automobiles and other machines that require constant supplies of lubrication, air, or other liquids in order for moving parts to run smoothly. Brakes, for example, use rotary unions to maintain a constant supply of pressurized brake fluid. Rotary unions are also heavily used in crude oil processing, the chemical industry, commercial food production, and pharmaceutical applications.\nAgriculture.\nEquipment used in grain harvesting including combines, tractors, grain carts and threshers employ rotary unions. Once harvested, many crops will be processed with equipment that uses rotary unions. Food processing equipment that use rotary unions include cooling conveyors, flaking mills, shredders, steam cookers, starch dryers, rotary cutters and roll-forming.\nAutomotive.\nAuto manufacturing is a diverse user of rotary unions for a broad range of parts or components and materials, whether machined steel, iron or aluminum, stampings, plastics, glass or paperboard. Rotary unions are used for operations that require coolant, lubricant or hydraulics.\nCar washes.\nThere are two kinds of car wash facilities that use unions: the automatic and the hand operated. Most manufacturers of automatic systems have several revolving brushes which use 55 series to introduce low pressure detergent water through the supporting shaft to the brushes. In addition, automatic car washes have spinners that require rotary unions to transmit high-pressure water into the spinning mechanisms.\nConverting.\nDownstream processing of paper, plastic film, foil and related substrate materials into finished, printed packaging such as bags, pouches, labels, tags, folding cartons and corrugated shipping cases is called converting. Rotary unions are used in all types of converting for water, steam, thermal oil, air or hydraulics.\nMachine tools.\nRotary unions may be used to transmit coolant, cutting oil, MQL, pressurized air in a bearingless or bearing supported configuration. Besides coolant delivery, rotary unions are used for chucking, tool sensing, rotary index table and other machine tool applications.\nMining.\nElectro-hydraulic equipment used in mining operations employ rotary unions including shuttle cars and coal cars, drill heads, backhoes, clam shell cranes and drag lines. In addition, boom hoists, retrieving drums and bucket drum clutches each require rotary unions.\nOil and gas.\nDrilling rigs (oil or gas) use air clutches and brakes that require rotary unions. Water unions are used to flush mud from the drill tip, and must withstand shock and vibration in this severe application. Oil and petrochemical refineries use batch mixers, flaking mills, blenders and drying rolls that each require rotary unions. The development of subsea oil and gas fields requires specialized equipment. Subsea swivels, manufactured by Dynamic Sealing Technologies, Inc., are designed for deepwater oil production systems that provide equipment operations added flexibility when lowering flowlines in harsh waters down to depths reaching 3,500 meters.\nPaper.\nPaper applications span the supply chain from the raw pulp and paper mills, to the downstream paper converters. Mills use steam joint and siphon systems and water unions for heating and cooling. Converters use rotary unions for heating and cooling rolls, as well as winders with air clutches and brakes.\nPlastics.\nThe manufacturing of plastic materials encompasses a wide variety of applications including cast film, blown film, foam, flexible and rigid sheet extrusion, single and multi-layer co-extrusion, blow molding, thermoforming, pelletizing, wire and cable, injection molding and winding. Rotary unions are used for heating or cooling the many processing rolls throughout the wide variety of applications. In addition, rotary unions for air and hydraulic service are used in winding and injection molding applications. Many of today's modern winding applications will also utilize electrical slip rings.\nPrinting.\nPrinting on flexible rolls of paper or plastic films requires rotary unions for air or hydraulics, as well as chill rolls for temperature control. Web offset and sheet printing equipment use many rotary unions on the ink vibrator and chill rolls.\nRubber.\nRubber is compounded on big industrial mixers which use rotary unions for water cooled rolls. Rubber extrusion is similar to plastic extrusion, with rotary unions used to cool the extruder screw.\nSteel.\nThe steel industry is one of the largest users of rotary unions primarily for continuous casting machines (CCM) which use rotary unions to cool the numerous rolls that support molten slabs as it moves by gravity through various segments onto a run-out table to downstream annealing and heat treating. The slab is formed into coil or sheet. Coil is further converted in processing centers that require hydraulic unions for actuation of mandrels.\nTextiles.\nThe textile industry is a large user of water, steam and hot oil unions. Weaving, dyeing and finishing processes are the largest users of rotary unions.\nTires.\nRubber tire plants use industrial mixers, extruders, calendar train cooling stacks and rayon slashers to make tire cord. Rotary unions are used in every process for temperature control.\nReferences.\nhttps://www.rix-us.com/rocky-rotary-joints/", "Engineering,_Manufacturing": 1.0000069141, "qwen": "Yes"}
{"id": "5673896", "revid": "31516478", "url": "https://en.wikipedia.org/wiki?curid=5673896", "title": "Fluke Corporation", "text": "Fluke Corporation manufactures industrial test, measurement, and diagnostic equipment, including electronic test equipment. It was started in 1948 by John Fluke while he was employed at General Electric.\nHistory.\nJohn Fluke founded Fluke Corporation in October 1953 as the John Fluke Manufacturing Company, Inc., producing electrical metering equipment.\nIn 1987, Fluke partnered with the Dutch electronics manufacturer Philips. Together, the companies developed the scopemeter, an instrument combining features of an oscilloscope and a multimeter. Fluke purchased the testing and measurements division of Philips in 1993 for $41.8 million. The Philips PM series of measurement instruments was rebranded as Fluke.\nFluke was bought by the Danaher Corporation in 1998. Danaher spun off several subsidiaries, including Fluke, in 2016 to create Fortive.\nSubsidiaries.\nPomona Electronics.\nPomona Electronics is a company specializing in electronic test equipment and accessories. It was founded in 1951 by Joseph J. and Carl W. Musarra, who were brothers. Founded to manufacture test cable harnesses for examining television cathode-ray tubes. the company started in a factory location around the size of a living room. By 1976, it was owned by ITT Industries, which in 1999 sold it to Fluke. In 2002, Pomona Electronics relocated its manufacturing facility to Everett, Washington.", "Engineering,_Manufacturing": 0.9962299466, "qwen": "Yes"}
{"id": "37909518", "revid": "398607", "url": "https://en.wikipedia.org/wiki?curid=37909518", "title": "C&I Eurotrans XXI", "text": "C&I Eurotrans XXI is a coachbuilder based in Bucharest, Romania. The company was established in 2002, and it is specialized in manufacturing coachwork for minibuses based on chassis from a series of other manufacturers.\nCibro.\nThe company's main product has been the Cibro minibus, introduced in 2005, and developed on a Mercedes-Benz Vario chassis. It featured a capacity range from 23 to 30 seats and was manufactured in four different levels of comfort.\nIn 2010, a new version of the minibus, called Cibro 2, was launched. It is manufactured at the new production facility, located in the village of , Ilfov County. The factory is ISO 9001 certificated and has been implementing ISO 14001 certification.", "Engineering,_Manufacturing": 0.9999167919, "qwen": "Yes"}
{"id": "16457295", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=16457295", "title": "Giles G-202", "text": "The Giles G-202 is an unlimited-level aerobatic airplane designed by Richard Giles.\nThis carbon fiber composite monoplane was manufactured by AkroTech Aviation in Troutdale, Oregon. The tandem two-seater was based upon the single-seater Giles G-200.\nThe G-202 was produced and sold as kit plane by AkroTech, and slightly modified as the CAP 222 by Avions Mudry (France).", "Engineering,_Manufacturing": 0.9998570681, "qwen": "Yes"}
{"id": "909187", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=909187", "title": "Service management", "text": "Service management in the manufacturing context, is integrated into supply chain management as the intersection between the actual sales and the customer point of view. The aim of high-performance service management is to optimize the service-intensive supply chains, which are usually more complex than the typical finished-goods supply chain. Most service-intensive supply chains require larger inventories and tighter integration with field service and third parties. They also must accommodate inconsistent and uncertain demand by establishing more advanced information and product flows. Moreover, all processes must be coordinated across numerous service locations with large numbers of parts and multiple levels in the supply chain.\nAmong typical manufacturers, post-sale services (maintenance, repair, and parts) account for less than 20% of revenue. But among the most innovative companies in service, those same activities often generate more than 50% of the profits.\nBenefits.\nThe main drivers for a company to establish or optimize its service management practices are varied:\nComponents.\nGenerally, service management comprises six different capabilities that companies should consider for optimization:", "Engineering,_Manufacturing": 0.9995361567, "qwen": "Yes"}
{"id": "1887020", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=1887020", "title": "CAD/CAM in the footwear industry", "text": "CAD/CAM in the footwear industry is the use of computers and graphics software for designing and grading of shoe upper patterns and, for manufacturing of cutting dies, shoe lasts and sole moulds. CAD/CAM software is a PC-based system, which is made up of program modules. Today, there are 2D and 3D versions of CAD/CAM systems in the shoe industry.\nComputer aided design was introduced in the shoe industry in the 1970s. Initially, it was used primarily for pattern grading. It enabled manufacturers to perform complex grading relatively easily and quickly. CAD systems today have been developed with a much wider range of functions. Logos, textures, and other decorations can be incorporated into product designs of both the uppers and soles to help reinforce branding on all areas of the model. It automates routine procedures, increasing speed and consistency, whilst reducing the possibility of mistakes. CAD data can now be used effectively for a wide variety of activities across footwear manufacturing business. CAD/CAM generates data at the design stage, which can be used right through the planning and manufacturing stages.\nLatest improvements in the CAD/CAM technology are:\nWith CAD/CAM software, footwear manufacturers can cut their time to market dramatically and so increase market share and profitability. In addition, the power and flexibility of the software can overcome restrictions to the designer's creativity imposed by traditional methods.\nSole design.\nCAD/CAM software can be used to generate machining data for shoe sole models and moulds Shoe sole mould makers are able to strengthen their capabilities of mould design and production techniques to meet the market demands for shorter product life cycle, quality improvement and handling versatile pattern design. This helps especially sports shoe producers to manufacture products rapidly and to introduce them earlier than their competitors.\n3D CAD/CAM is the core technology for shoe sole mould in the footwear industry and develops towards specialization.\nBenefits of CAD/CAM in the mould manufacturing are:\nReferences and suppliers.\nCommercial suppliers of CAD CAM for the footwear industry are listed on Shoeinfonet.com:\n\nLondon College of Fashion library web site lists some of the same\n\nNo specialised open sources suppliers are listed, although Wikipedia lists several free general purpose products for 2D CAD/CAM and some for 3D.", "Engineering,_Manufacturing": 0.9999967813, "qwen": "Yes"}
{"id": "55315552", "revid": "1155105872", "url": "https://en.wikipedia.org/wiki?curid=55315552", "title": "Vibration welding of thermoplastics", "text": "Vibration welding (also known as linear or friction welding) refers to a process in which two workpieces are brought in contact under pressure, and a reciprocating motion (vibration) is applied along the common interface in order to generate heat. The resulting heat melts the workpieces, and they become welded when the vibration stops and the interface cools. Most machinery operates at 120 Hz, although equipment is available that runs between 100–240 Hz. Vibration can be achieved either through linear vibration welding, which uses a one dimensional back and forth motion, or orbital vibration welding which moves the pieces in small orbits relative to each other. Linear vibration welding is more common due to simpler and relatively cheaper machinery required.\nVibration welding is often used for larger applications where the parts to be joined have relatively flat seams, although the process can accommodate some out of plane curvature. Recently, the automotive industry has made extensive use of the process to produce parts like manifolds and lighting assemblies whose complex geometries prevent single component molding processes.\nAdvantages and disadvantages.\nVibration welding has numerous advantages over other conventional plastic welding processes. Since the heat is created at an interface, the molten polymers are not exposed to open air, preventing oxidation and contamination of the weld during the process. No filler material is required, and when welding components of the same material the joint can be expected to be just as strong as the bulk material. Heating is localized to the interface, decreasing the chances of material degradation seen with other processes which require a heat source well above the melt temperature of the material. The process itself is cost effective, with no consumables and short cycle times. Vibration welding produces virtually no smoke or fume, requires little surface preparation, and works well for a multitude of applications, making it well suited to mass production environments.\nVibration welding does have its drawbacks, however. The process does not lend itself well to low modulus thermoplastics or to joints between plastics with relatively high differences in melting temperatures. Vibration welding requires part specific fixturing and joint designs, and the part will be exposed to rigorous vibration during the welding cycle which may damage sensitive or miniature components. The finished weld will be surrounded by a significant amount of flash, which must be removed if appearance is an issue. Alternatively, joint geometries which hide the excess flash can be used. Lastly, the process is not well suited to welding of anything other than relatively flat joints.\nVibration welding process.\nThe vibration welding process consists of four steps: solid friction, transient flow, steady state flow, and solidification.\nSolid friction.\nIn this first stage, vibration is commenced between two cold parts pressed together at a constant pressure. The frictional energy causes the polymers to heat. In this stage there is no weld penetration as melting has not yet occurred.\nTransient flow.\nIn the transient flow step the polymer's surface begins to melt. The melt layer thickness quickly grows, causing the frictional forces to decrease. This decrease in friction decreases the heat input to the system, and a lateral flow of molten material begins to occur.\nSteady state flow.\nIn this phase the melting rate of the material matches the flow of material extruded at the lateral surfaces. The material flow and thickness of the melt layer become constant. This is the step that determines the quality of the weld. This step is maintained until the desired ‘melt down’ thickness (thickness of the molten material) is achieved. At that time the vibration is stopped and the weld is allowed to cool.\nSolidification.\nDuring solidification the vibration is stopped, while pressure is maintained on the workpieces until no more molten material remains. Once cooled to room temperature, the joint should have near the strength of the bulk material. Pressure is only relieved once the joint reaches an acceptable strength.\nEquipment.\nA vibration welding machine is essentially a vertical machine press in which one side has been modified to vibrate.  The main components are the vibrating assembly, a lifting table, and a tooling fixture.\nVibrating assembly.\nThe vibrating assembly is a moving element driven either by hydraulics or more commonly, electromagnets. In the electromagnetic version, the heart of this assembly is a tuned spring-mass system powered by electrical coils acting on oppositely charged lamination stacks. The frequency of the electrical charges is matched to the mechanical frequency of the system. Although the amplitude can be adjusted on the machine the frequency can only be changed by changing the mass of the vibrating assembly. The moving portion of the tooling is affixed to the vibrating assembly.\nLifting table.\nThe lifting table is a hydraulic assembly attached to the fixed portion of the tooling. The lifting table brings the workpieces together, and applies pressure between the moving and stationary portions of the tooling.\nTooling.\nTooling refers to the fixtures which are attached to the vibrating assembly and lifting table that hold the work pieces in place. Tooling is application specific, and must allow for workpieces to be quickly switched out after every welding cycle. It is imperative that the tooling matches the workpieces closely enough to prevent any relative motion between the tooling and the workpieces, as this would reduce the amplitude of the weld and lower heat input as well as dimensional tolerances.\nProcess variables.\nThe vibration welding process has five main variables: frequency, amplitude, pressure, time, and depth.\nFrequency.\nFrequency refers to how many times per second a vibration cycle is completed. Most machinery runs at 120 Hz, although machinery is available that runs from 100–240 Hz. Frequency is dependent on the mass of the vibrating assembly, and as such can only be changed by switching out components of the assembly.\nAmplitude.\nAmplitude refers to the distance traveled during each vibratory cycle. Higher amplitudes tend to be used with lower frequencies, and vice versa. Higher amplitudes increase heat input at the cost of cleanliness and dimensional tolerances, making them more useful for larger parts. Lower amplitudes range from 0.7-1.8mm, while higher amplitudes describe cycles that cover 2-4mm.\nPressure.\nPressure is the primary controller of melt layer thickness, and must be kept within an optimal range in order to produce quality joints. Although pressure can vary between 0.5-20MPa across different materials and geometries, the tolerances for a given application are quite tight. Too little pressure will prevent sufficient heat generation, while too much pressure can cause all of the molten material to squeeze out of the joint. Both scenarios will result in a weak weld. Pressure is controlled by the lifting table.\nTime.\nThe length of time that vibration is applied to the workpiece is another key factor. Time is directly proportional to heat generation and material loss to flash. Processes can be either time or depth controlled, with most modern processes being depth controlled. A depth controlled process will have a variable time, and vice versa.\nDepth.\nDepth refers to the distance traveled by the workpieces after vibration is started. Sometimes referred to as displacement, it is directly related to the amount of material loss to flash. In general depth should be kept close to or above the thickness of the melt layer at the beginning of the steady state stage. After this value, more depth only results in loss of material without an accompanying rise in joint strength.\nWeld design.\nWeld design for vibration welding must include a relatively large flat surface, although some out of plane curvature can be accommodated for. The most common type of joint is a butt joint, where two flat pieces with the same cross section are welded together. Variations on this joint can include u-flanges, tongue and groove joints, and even double tongue and groove joints. When appearances are important, flash traps can be used. Flash traps refer to  hollow areas in the cross section next to the weld area that collect the flash and hide it from view.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "23535218", "revid": "21112944", "url": "https://en.wikipedia.org/wiki?curid=23535218", "title": "Industrial engineering", "text": "Industrial engineering is an engineering profession that is concerned with the optimization of complex processes, systems, or organizations by developing, improving and implementing integrated systems of people, money, knowledge, information and equipment. Industrial engineering is central to manufacturing operations. \nIndustrial engineers use specialized knowledge and skills in the mathematical, physical and social sciences, together with the principles and methods of engineering analysis and design, to specify, predict, and evaluate the results obtained from systems and processes. There are several industrial engineering principles followed in the manufacturing industry to ensure the effective flow of the systems, processes and operations. \nThis includes:\nThese principles allow the creation of new systems, processes or situations for the useful coordination of labor, materials and machines and also improve the quality and productivity of systems, physical or social. Depending on the subspecialties involved, industrial engineering may also overlap with, operations research, systems engineering, manufacturing engineering, production engineering, supply chain engineering, management science, management engineering, financial engineering, ergonomics or human factors engineering, safety engineering, logistics engineering or others, depending on the viewpoint or motives of the user.\nHistory.\nOrigins.\nIndustrial engineering.\nThere is a general consensus among historians that the roots of the industrial engineering profession date back to the Industrial Revolution. The technologies that helped mechanize traditional manual operations in the textile industry including the flying shuttle, the spinning jenny, and perhaps most importantly the steam engine generated economies of scale that made mass production in centralized locations attractive for the first time. The concept of the production system had its genesis in the factories created by these innovations. It has also been suggested that perhaps Leonardo da Vinci was the first industrial engineer because there is evidence that he applied science to the analysis of human work by examining the rate at which a man could shovel dirt around the year 1500. Others also state that the industrial engineering profession grew from Charles Babbage’s study of factory operations and specifically his work on the manufacture of straight pins in 1832 . However, it has been generally argued that these early efforts, while valuable, were merely observational and did not attempt to engineer the jobs studied or increase overall output.\nSpecialization of labour.\nAdam Smith's concepts of Division of Labour and the \"Invisible Hand\" of capitalism introduced in his treatise \"The Wealth of Nations\" motivated many of the technological innovators of the Industrial Revolution to establish and implement factory systems. The efforts of James Watt and Matthew Boulton led to the first integrated machine manufacturing facility in the world, including the application of concepts such as cost control systems to reduce waste and increase productivity and the institution of skills training for craftsmen.\nCharles Babbage became associated with industrial engineering because of the concepts he introduced in his book \"On the Economy of Machinery and Manufacturers\" which he wrote as a result of his visits to factories in England and the United States in the early 1800s. The book includes subjects such as the time required to perform a specific task, the effects of subdividing tasks into smaller and less detailed elements, and the advantages to be gained from repetitive tasks.\nInterchangeable parts.\nEli Whitney and Simeon North proved the feasibility of the notion of interchangeable parts in the manufacture of muskets and pistols for the US Government. Under this system, individual parts were mass-produced to tolerances to enable their use in any finished product. The result was a significant reduction in the need for skill from specialized workers, which eventually led to the industrial environment to be studied later.\nPioneers.\nFrederick Taylor (1856–1915) is generally credited as being the father of the industrial engineering discipline. He earned a degree in mechanical engineering from Stevens Institute of Technology and earned several patents from his inventions. His books, \"Shop Management\" and \"The Principles of Scientific Management\", which were published in the early 1900s, were the beginning of industrial engineering. Improvements in work efficiency under his methods was based on improving work methods, developing of work standards, and reduction in time required to carry out the work. With an abiding faith in the scientific method, Taylor did many experiments in machine shop work on machines as well as men. Taylor developed \"time study\" to measure time taken for various elements of a task and then used the study observations to reduce the time further. Time study was done for the improved method once again to provide time standards which are accurate for planning manual tasks and also for providing incentives.\nThe husband-and-wife team of Frank Gilbreth (1868–1924) and Lillian Gilbreth (1878–1972) was the other cornerstone of the industrial engineering movement whose work is housed at Purdue University School of Industrial Engineering. They categorized the elements of human motion into 18 basic elements called therbligs. This development permitted analysts to design jobs without knowledge of the time required to do a job. These developments were the beginning of a much broader field known as human factors or ergonomics.\nIn 1908, the first course on industrial engineering was offered as an elective at Pennsylvania State University, which became a separate program in 1909 through the efforts of Hugo Diemer. The first doctoral degree in industrial engineering was awarded in 1933 by Cornell University.\nIn 1912, Henry Laurence Gantt developed the Gantt chart, which outlines actions the organization along with their relationships. This chart opens later form familiar to us today by Wallace Clark.\nWith the development of assembly lines, the factory of Henry Ford (1913) accounted for a significant leap forward in the field. Ford reduced the assembly time of a car from more than 700 hours to 1.5 hours. In addition, he was a pioneer of the economy of the capitalist welfare (\"welfare capitalism\") and the flag of providing financial incentives for employees to increase productivity.\nIn 1927, the then Technische Hochschule Berlin was the first German university to introduce the degree. The course of studies developed by Willi Prion was then still called Business and Technology and was intended to provide descendants of industrialists with an adequate education. \nComprehensive quality management system (Total quality management or TQM) developed in the forties was gaining momentum after World War II and was part of the recovery of Japan after the war.\nThe American Institute of Industrial Engineering was formed in 1948. The early work by F. W. Taylor and the Gilbreths was documented in papers presented to the American Society of Mechanical Engineers as interest grew from merely improving machine performance to the performance of the overall manufacturing process, most notably starting with the presentation by Henry R. Towne (1844–1924) of his paper \"The Engineer as An Economist\" (1886).\nModern practice.\nFrom 1960 to 1975, with the development of decision support systems in supply such as material requirements planning (MRP), one can emphasize the timing issue (inventory, production, compounding, transportation, etc.) of industrial organization. Israeli scientist Dr. Jacob Rubinovitz installed the CMMS program developed in IAI and Control-Data (Israel) in 1976 in South Africa and worldwide.\nIn the 1970s, with the penetration of Japanese management theories such as Kaizen and Kanban, Japan realized very high levels of quality and productivity. These theories improved issues of quality, delivery time, and flexibility. Companies in the west realized the great impact of Kaizen and started implementing their own continuous improvement programs. W. Edwards Deming made significant contributions in the minimization of variance starting in the 1950s and continuing to the end of his life. \nIn the 1990s, following the global industry globalization process, the emphasis was on supply chain management and customer-oriented business process design. The theory of constraints, developed by Israeli scientist Eliyahu M. Goldratt (1985), is also a significant milestone in the field.\nComparison to other engineering disciplines.\nEngineering is traditionally decompositional. To understand the whole of something, it is first broken down into its parts. One masters the parts, then puts them back together to create a better understanding of how to master the whole. The approach of industrial and systems engineering (ISE) is opposite; any one part cannot be understood without the context of the whole system. Changes in one part of the system affect the entire system, and the role of a single part is to better serve the whole system.\nAlso, industrial engineering considers the human factor and its relation to the technical aspect of the situation and all of the other factors that influence the entire situation, while other engineering disciplines focus on the design of inanimate objects.\n\"Industrial Engineers integrate combinations of people, information, materials, and equipment that produce innovative and efficient organizations. In addition to manufacturing, Industrial Engineers work and consult in every industry, including hospitals, communications, e-commerce, entertainment, government, finance, food, pharmaceuticals, semiconductors, sports, insurance, sales, accounting, banking, travel, and transportation.\"\n\"Industrial Engineering is the branch of Engineering most closely related to human resources in that we apply social skills to work with all types of employees, from engineers to salespeople to top management. One of the main focuses of an Industrial Engineer is to improve the working environments of people – not to change the worker, but to change the workplace.\"\n\"All engineers, including Industrial Engineers, take mathematics through calculus and differential equations. Industrial Engineering is different in that it is based on discrete variable math, whereas all other engineering is based on continuous variable math. We emphasize the use of linear algebra and difference equations, as opposed to the use of differential equations which are so prevalent in other engineering disciplines. This emphasis becomes evident in optimization of production systems in which we are sequencing orders, scheduling batches, determining the number of materials handling units, arranging factory layouts, finding sequences of motions, etc. As, Industrial Engineers, we deal almost exclusively with systems of discrete components.\"\nEtymology.\nEtymology.\nWhile originally applied to manufacturing, the use of \"industrial\" in \"industrial engineering\" can be somewhat misleading, since it has grown to encompass any methodical or quantitative approach to optimizing how a process, system, or organization operates. In fact, the \"industrial\" in \"industrial engineering\" means the industry in its broadest sense. People have changed the term \"industrial\" to broader terms such as industrial and manufacturing engineering, industrial and systems engineering, industrial engineering and operations research, industrial engineering and management.\nSub-disciplines.\nIndustrial engineering has many sub-disciplines, the most common of which are listed below. Although there are industrial engineers who focus exclusively on one of these sub-disciplines, many deals with a combination of them such as supply chain and logistics, and facilities and energy management.\nMethods engineering\nFacilities engineering & energy management\nFinancial engineering\nEnergy engineering\nHuman factors & safety engineering\nInformation systems engineering & management\nManufacturing engineering\nOperations engineering & managementOperations research & optimization\nPolicy planning\nProduction engineeringQuality & reliability engineering\nSupply chain management & logistics\nSystems engineering & analysis\nSystems simulation\nRelated disciplines\nOrganization development & change management\nBehavioral economics\nEducation.\nIndustrial engineers study the interaction of human beings with machines, materials, information, procedures and environments in such developments and in designing a technological system.\nIndustrial engineering degrees accredited within any member country of the Washington Accord enjoy equal accreditation within all other signatory countries, thus allowing engineers from one country to practice engineering professionally in any other.\nUniversities offer degrees at the bachelor, masters, and doctoral level.\nUndergraduate curriculum.\nIn the United States, the undergraduate degree earned is either a bachelor of science (B.S.) or a bachelor of science and engineering (B.S.E.) in industrial engineering (IE). In South Africa, the undergraduate degree is a bachelor of engineering (BEng). Variations of the title include Industrial & Operations Engineering (IOE), and Industrial & Systems Engineering (ISE or ISyE). \nThe typical curriculum includes a broad math and science foundation spanning chemistry, physics, mechanics (i.e., statics, kinematics, and dynamics), materials science, computer science, electronics/circuits, engineering design, and the standard range of engineering mathematics (i.e., calculus, linear algebra, differential equations, statistics). For any engineering undergraduate program to be accredited, regardless of concentration, it must cover a largely similar span of such foundational work – which also overlaps heavily with the content tested on one or more engineering licensure exams in most jurisdictions.\nThe coursework specific to IE entails specialized courses in areas such as optimization, applied probability, stochastic modeling, design of experiments, statistical process control, simulation, manufacturing engineering, ergonomics/safety engineering, and engineering economics. Industrial engineering elective courses typically cover more specialized topics in areas such as manufacturing, supply chains and logistics, analytics and machine learning, production systems, human factors and industrial design, and service systems.\nCertain business schools may offer programs with some overlapping relevance to IE, but the engineering programs are distinguished by a much more intensely quantitative focus, required engineering science electives, and the core math and science courses required of all engineering programs.\nGraduate curriculum.\nThe usual graduate degree earned is the master of science (MS), master of science and engineering (MSE) or master of engineering (MEng) in industrial engineering or various alternative related concentration titles.\nTypical MS curricula may cover:\nDifferences in teaching.\nWhile industrial engineering as a formal degree has been around for years, consensus on what topics should be taught and studied differs across countries. For example, Turkey focuses on a very technical degree while Denmark, Finland and the United Kingdom have a management focus degree, thus making it less technical. The United States, meanwhile, focuses on case studies, group problem solving and maintains a balance between the technical and non-technical side.\nPracticing engineers.\nTraditionally, a major aspect of industrial engineering was planning the layouts of factories and designing assembly lines and other manufacturing paradigms. And now, in lean manufacturing systems, industrial engineers work to eliminate wastes of time, money, materials, energy, and other resources.\nExamples of where industrial engineering might be used include flow process charting, process mapping, designing an assembly workstation, strategizing for various operational logistics, consulting as an efficiency expert, developing a new financial algorithm or loan system for a bank, streamlining operation and emergency room location or usage in a hospital, planning complex distribution schemes for materials or products (referred to as supply-chain management), and shortening lines (or queues) at a bank, hospital, or a theme park.\nModern industrial engineers typically use predetermined motion time systems, computer simulation (especially discrete event simulation), along with extensive mathematical tools for modeling, such as mathematical optimization and queueing theory, and computational methods for system analysis, evaluation, and optimization. Industrial engineers also use the tools of data science and machine learning in their work owing to the strong relatedness of these disciplines with the field and the similar technical background required of industrial engineers (including a strong foundation in probability theory, linear algebra, and statistics, as well as having coding skills).", "Engineering,_Manufacturing": 0.9999877214, "qwen": "Yes"}
{"id": "23540248", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=23540248", "title": "Capability (systems engineering)", "text": "A capability, in the systems engineering sense, is defined as the ability to execute a specified course of action. A capability may or may not be accompanied by an intention. The term is used in the defense industry but also in private industry (e.g. gap analysis).\nCapability gap analysis.\nThe Joint Capabilities Integration Development System is an important part of DoD military planning. The \"Operation of the JCIDS\" introduces a Capability Based Analysis (CBA) process that includes identification of capability gaps. In essence, a Capability Gap Analysis is the determination of needed capabilities that do not yet exist. The Department of Defense Architecture Framework (DoDAF) suggests the use of the Operational Activity Model (OV-5) in conducting a CGA.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "68921497", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=68921497", "title": "Medigen Vaccine Biologics Corporation", "text": "The Medigen Vaccine Biologics Corporation (MVC; ) is a pharmaceutical company headquartered in Neihu, Taipei, Taiwan.\nHistory.\nThe company was founded in October 2012. During the COVID-19 pandemic in Taiwan, the company produces the MVC COVID-19 vaccine to fight the virus.\nManufacturing plant.\nThe company has a manufacturing plant in Hsinchu Biomedical Science Park, Zhubei City, Hsinchu County.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "27982993", "revid": "6603956", "url": "https://en.wikipedia.org/wiki?curid=27982993", "title": "The Genie Company", "text": "GMI Holdings Inc. (dba The Genie Company) is an American manufacturer of garage door openers & related accessories. It was founded in 1923 as the Alliance Manufacturing Company, located in Alliance, Ohio. At the time the company produced a broad line of consumer, industrial and military products. In May 1954, the Alliance Manufacturing Company first produced its own garage door opener and called it Genie. In 1983 the company entered the home and shop vacuum market, and in 1985 it changed its name to Genie Home Products. Overhead Door Corporation purchased the company in 1994. The Genie Company is headquartered in Mt. Hope, Ohio. The company distributes its openers & accessories through professional dealers and retailers throughout the United States and Canada. The company President is Mike Kridel.\nGenie's factory is located in nearby Baltic, Ohio.", "Engineering,_Manufacturing": 0.9991058111, "qwen": "Yes"}
{"id": "63256598", "revid": "38427", "url": "https://en.wikipedia.org/wiki?curid=63256598", "title": "StreetScooter C16", "text": "The StreetScooter C16 was an electric car shown in 2014 by the electric vehicle manufacturer StreetScooter (otherwise known for making electric commercial vehicles).\nThe 2-seater city car had a metal frame, however all of its exterior plastic parts were 3D-printed on the Objet1000 printer by Stratasys using ABS polymer. The production vehicle was meant to weigh about 450 kg without the battery, have a \"minimum\" range of 100 km, reach a top speed of 100 km/h and have a price tag of under 10,000 EUR.\nThe vehicle was shown at the EuroMold in Frankfurt in 2014.", "Engineering,_Manufacturing": 1.0000069141, "qwen": "Yes"}
{"id": "31008821", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=31008821", "title": "Conveyor belt furnace", "text": "A conveyor belt furnace is a furnace that uses a conveyor or a belt to carry process parts or material through the primary heating chamber for rapid thermal processing. It is designed for fast drying and curing of products and is nowadays widely used in the firing process of thick film and metallization process of solar cell manufacturing. Other names for conveyor belt furnace include metallization furnace, belt furnace, atmosphere furnace, infrared furnace and fast fire furnace.\nUsually, a conveyor furnace adopts a tunnel structure and is composed of multiple controlled zones which include zones for preheating, binder burn out, heating, firing, and cooling. A conveyor furnace also features fast thermal responses, uniform and stable temperature distribution; it can heat treated parts to around 1050 °C. Belt speed of a conveyor furnace can be up to 6000mm/min. Products are heated efficiently by infrared radiation (it can also be ceramic heaters or IR lamps) and are dried and fired after passing through the controlled zones, followed by rapid cooling.\nProcess applications.\nThick film processing.\nAfter a paste is screened onto a substrate and it settles for 5–15 minutes at room temperature, it undergoes oven drying at 100-150 °C for 10–15 minutes to remove solvents. Firing is then completed in conveyor belt furnaces at temperatures between 500 and 1000 °C.\nCrystalline silicon solar cell Manufacturing.\nElectrical contacts are usually formed by screen printing. The firing is done in conveyor belt furnaces at a temperature of about 700 °C for a few minutes. Upon firing, the organic solvents evaporate and the metal powder becomes a conducting path for the electric current.\nThin film solar cell manufacturing.\nA transparent conducting glass, coated with doped SnO2 or ITO film, is used as a substrate. A thin film, such as CdS, is then deposited through CSS or CBD techniques. The CdS film is heat treated by a conveyor belt furnace in a reducing atmosphere or in the presence of CdCl2 at 400-500 °C.\nDye-sensitized solar cell (DSSC) manufacturing.\nTiO2 nanoparticles have been used extensively to increase the interfacial surface area in dye-sensitized solar cells. Nanoparticle films are generally made by screen printing a paste of titania nanocrystals and then sintering the particles together at 450-500 °C in a conveyor belt furnace.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "24134134", "revid": "41840956", "url": "https://en.wikipedia.org/wiki?curid=24134134", "title": "Gunther Mele", "text": "Gunther Mele Ltd. is a Canadian manufacturer and supplier of retail packaging. The company's headquarters are located in Brantford, Ontario. Gunther Mele is privately owned and has operations in the United States, China and Canada.\nHistory.\nGunther Mele was established in 1857 by two German immigrant brothers and was originally named the E&A Gunther Company. The company’s mission statement was \"Everything for the Jeweler except Jewelry\". They supplied jewelry packaging, watch materials, and workshop tools to independent jewelers, jewelry chain stores, and large department store jewelry departments.\nIn 1962, a great-grandson of the founders was killed in an automobile accident after leaving a trade show. His widow sold the company to Mele Manufacturing Company of Utica, New York. In 1987, Douglas M. King, who is the current owner and CEO, purchased Gunther Mele from Mele Manufacturing. Mele Manufacturing was a major jewelry case manufacturer which owned Farrington Packaging, which itself made cases for Cross Pen, Schick Shavers and many consumer product companies. His son, Darrell King, joined the company in 1995 and now serves as the company's president.\nBusiness Overview.\nOver the years, the company has evolved into one of the largest suppliers of packaging and packaging-related products in North America. The company employs over 250 people in two facilities including a manufacturing plant in Brantford, Ontario, Canada, and an operation in Buffalo, New York, United States.\nThe company manufactures cotton-filled paper boxes as well as poly bags, paper bags, reusable bags, and a variety of printed ribbon, seals and packaging accessories. Gunther Mele has been an early adopter of environmentally friendly packaging, licensing TDPA oxo-biodegradable technology from epi-global and utilizing FSC approved suppliers of papers for it shopping bags. Reusable non-woven fabric style bags have become a major category for Gunther Mele.\nIn addition to manufacturing capabilities, the company has more than thirty years experience working with manufacturers in Asia and established a \"working venture\" with several overseas manufacturers. Product volume with these three manufacturing companies in China is substantial and allows the company to control production schedules, quality and delivery. Gunther Mele also owns a Chinese company called KDI Limited, located in Hong Kong, which acts as a sourcing agent, liaises with factories in quality, delivery and production methods and facilitates the company's importing activities.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "14348925", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=14348925", "title": "Hicks-neutral technical change", "text": "Hicks-neutral technical change is change in the production function of a business or industry which satisfies certain economic neutrality conditions. The concept of Hicks neutrality was first put forth in 1932 by John Hicks in his book \"The Theory of Wages\". A change is considered to be Hicks neutral if the change does not affect the balance of labor and capital in the products' production function. More formally, given the Solow model production function\na Hicks-neutral change is one which only changes formula_2.", "Engineering,_Manufacturing": 0.9995972514, "qwen": "Yes"}
{"id": "14350137", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=14350137", "title": "Through-silicon via", "text": "In electronic engineering, a through-silicon via (TSV) or through-chip via is a vertical electrical connection (via) that passes completely through a silicon wafer or die. TSVs are high-performance interconnect techniques used as an alternative to wire-bond and flip chips to create 3D packages and 3D integrated circuits. Compared to alternatives such as package-on-package, the interconnect and device density is substantially higher, and the length of the connections becomes shorter.\nClassification.\nDictated by the manufacturing process, there exist three different types of TSVs: \"via-first TSVs\" are fabricated before the individual component (transistors, capacitors, resistors, etc.) are patterned (front end of line, FEOL), \"via-middle TSVs\" are fabricated after the individual component are patterned but before the metal layers (back-end-of-line, BEOL), and \"via-last TSVs\" are fabricated after (or during) the BEOL process. Via-middle TSVs are currently a popular option for advanced 3D ICs as well as for interposer stacks.\nTSVs through the front end of line (FEOL) have to be carefully accounted for during the EDA and manufacturing phases. That is because TSVs induce thermo-mechanical stress in the FEOL layer, thereby impacting the transistor behaviour.\nApplications.\nImage sensors.\nCMOS image sensors (CIS) were among the first applications to adopt TSV(s) in volume manufacturing. In initial CIS applications, TSVs were formed on the backside of the image sensor wafer to form interconnects, eliminate wire bonds, and allow for reduced form factor and higher-density interconnects. Chip stacking came about only with the advent of backside illuminated (BSI) CIS, and involved reversing the order of the lens, circuitry, and photodiode from traditional front-side illumination so that the light coming through the lens first hits the photodiode and then the circuitry. This was accomplished by flipping the photodiode wafer, thinning the backside, and then bonding it on top of the readout layer using a direct oxide bond, with TSVs as interconnects around the perimeter.\n3D packages.\nA 3D package (System in Package, Chip Stack MCM, etc.) contains two or more chips (integrated circuits) stacked vertically so that they occupy less space and/or have greater connectivity. An alternate type of 3D package can be found in IBM's Silicon Carrier Packaging Technology, where ICs are not stacked but a carrier substrate containing TSVs is used to connect multiple ICs together in a package. In most 3D packages, the stacked chips are wired together along their edges; this edge wiring slightly increases the length and width of the package and usually requires an extra “interposer” layer between the chips. In some new 3D packages, TSVs replace edge wiring by creating vertical connections through the body of the chips. The resulting package has no added length or width. Because no interposer is required, a TSV 3D package can also be flatter than an edge-wired 3D package. This TSV technique is sometimes also referred to as TSS (Through-Silicon Stacking or Thru-Silicon Stacking).\n3D integrated circuits.\nA 3D integrated circuit (3D IC) is a single integrated circuit built by stacking silicon wafers and/or dies and interconnecting them vertically so that they behave as a single device. By using TSV technology, 3D ICs can pack a great deal of functionality into a small “footprint.” The different devices in the stack may be heterogeneous, e.g. combining CMOS logic, DRAM and III-V materials into a single IC. In addition, critical electrical paths through the device can be drastically shortened, leading to faster operation. The Wide I/O 3D DRAM memory standard (JEDEC JESD229) includes TSV in the design.\nHistory.\nThe origins of the TSV concept can be traced back to William Shockley's patent \"Semiconductive Wafer and Method of Making the Same\" filed in 1958 and granted in 1962, which was further developed by IBM researchers Merlin Smith and Emanuel Stern with their patent \"Methods of Making Thru-Connections in Semiconductor Wafers\" filed in 1964 and granted in 1967, the latter describing a method for etching a hole through silicon. TSV was not originally designed for 3D integration, but the first 3D chips based on TSV were invented later in the 1980s.\nThe first three-dimensional integrated circuit (3D IC) stacked chips fabricated with a TSV process were invented in 1980s Japan. Hitachi filed a Japanese patent in 1983, followed by Fujitsu in 1984. In 1986, Fujitsu filed a Japanese patent describing a stacked chip structure using TSV. In 1989, Mitsumasa Koyonagi of Tohoku University pioneered the technique of wafer-to-wafer bonding with TSV, which he used to fabricate a 3D LSI chip in 1989. In 1999, the Association of Super-Advanced Electronics Technologies (ASET) in Japan began funding the development of 3D IC chips using TSV technology, called the \"R&D on High Density Electronic System Integration Technology\" project. The Koyanagi Group at Tohoku University used TSV technology to fabricate a three-layer stacked image sensor chip in 1999, a three-layer memory chip in 2000, a three-layer artificial retina chip in 2001, a three-layer microprocessor in 2002, and a ten-layer memory chip in 2005.\nThe inter-chip via (ICV) method was developed in 1997 by a FraunhoferSiemens research team including Peter Ramm, D. Bollmann, R. Braun, R. Buchner, U. Cao-Minh, Manfred Engelhardt and Armin Klumpp. It was a variation of the TSV process, and was later called SLID (solid liquid inter-diffusion) technology.\nThe term \"through-silicon via\" (TSV) was coined by Tru-Si Technologies researchers Sergey Savastiouk, O. Siniaguine, and E. Korczynski, who proposed a TSV method for a 3D wafer-level packaging (WLP) solution in 2000. Savastiouk later became the co-founder and CEO of ALLVIA Inc. From the beginning, his vision of the business plan was to create a through silicon interconnect since these would offer significant performance improvements over wire bonds. Savastiouk published two articles on the topic in Solid State Technology, first in January 2000 and again in 2010. The first article “Moore’s Law – The Z Dimension” was published in Solid State Technology magazine in January 2000. This article outlined the roadmap of the TSV development as a transition from 2D chip stacking to wafer level stacking in the future. In one of the sections titled Through Silicon Vias, Dr. Sergey Savastiouk wrote, “Investment in technologies that provide both wafer-level vertical miniaturization (wafer thinning) and preparation for vertical integration (through silicon vias) makes good sense.” He continued, “By removing the arbitrary 2D conceptual barrier associated with Moore’s Law, we can open up a new dimension in ease of design, test, and manufacturing of IC packages. When we need it the most – for portable computing, memory cards, smart cards, cellular phones, and other uses – we can follow Moore’s Law into the Z dimension.” This was the first time the term \"through-silicon via\" was used in a technical publication.\nCMOS image sensors utilising TSV were commercialized by companies including Toshiba, Aptina and STMicroelectronics during 20072008, with Toshiba naming their technology \"Through Chip Via\" (TCV). 3D-stacked random-access memory (RAM) was commercialized by Elpida Memory, which developed the first 8GB DRAM chip (stacked with four DDR3 SDRAM dies) in September 2009, and released it in June 2011. TSMC announced plans for 3D IC production with TSV technology in January 2010. In 2011, SK Hynix introduced 16GB DDR3 SDRAM (40nm class) using TSV technology, Samsung Electronics introduced 3D-stacked 32GB DDR3 (30nm class) based on TSV in September, and then Samsung and Micron Technology announced TSV-based Hybrid Memory Cube (HMC) technology in October. SK Hynix manufactured the first High Bandwidth Memory (HBM) chip, based on TSV technology, in 2013.", "Engineering,_Manufacturing": 0.9999861717, "qwen": "Yes"}
{"id": "30655042", "revid": "41807748", "url": "https://en.wikipedia.org/wiki?curid=30655042", "title": "Tin-silver-copper", "text": "Tin-silver-copper (Sn-Ag-Cu, also known as SAC), is a lead-free (Pb-free) alloy commonly used for electronic solder. It is the main choice for lead-free surface-mount technology (SMT) assembly in the industry, as it is near eutectic, with adequate thermal fatigue properties, strength, and wettability. Lead-free solder is gaining much attention as the environmental effects of lead in industrial products is recognized, and as a result of Europe's RoHS legislation to remove lead and other hazardous materials from electronics. Japanese electronics companies have also looked at Pb-free solder for its industrial advantages.\nTypical alloys are 3–4% silver, 0.5–0.7% copper, and the balance (95%+) tin. For example, the common \"SAC305\" solder is 3.0% silver and 0.5% copper. Cheaper alternatives with less silver are used in some applications, such as SAC105 and SAC0307 (0.3% silver, 0.7% copper), at the expense of a somewhat higher melting point.\nHistory.\nIn 2000, there were several lead-free assemblies and chip products initiatives being driven by the Japan Electronic Industries Development Association (JEIDA) and Waste Electrical and Electronic Equipment Directive (WEEE). These initiatives resulted in tin-silver-copper alloys being considered and tested as lead-free solder ball alternatives for array product assemblies.\nIn 2003, tin-silver-copper was being used as a lead-free solder. However, its performance was criticized because it left a dull, irregular finish and it was difficult to keep the copper content under control. In 2005, tin-silver-copper alloys constituted approximately 65% of lead-free alloys used in the industry and this percentage has been increasing. Large companies such as Sony and Intel switched from using lead-containing solder to a tin-silver-copper alloy.\nConstraints and tradeoffs.\nThe process requirements for (Pb-free) SAC solders and Sn-Pb solders are different both materially and logistically for electronic assembly. In addition, the reliability of Sn-Pb solders is well established, while SAC solders are still undergoing study, (though much work has been done to justify the use of SAC solders, such as the iNEMI Lead Free Solder Project).\nOne important difference is that Pb-free soldering requires higher temperatures and increased process control to achieve the same results as that of the tin-lead method. The melting point of SAC alloys is 217–220°C, or about 34°C higher than the melting point of the eutectic tin-lead (63/37) alloy. This requires peak temperatures in the range of 235–245°C to achieve wetting and wicking.\nSome of the components susceptible to SAC assembly temperatures are electrolytic capacitors, connectors, opto-electronics, and older style plastic components. However, a number of companies have started offering 260 °C compatible components to meet the requirements of Pb-free solders. iNEMI has proposed that a good target for development purposes would be around 260°C.\nAlso, SAC solders are alloyed with a larger number of metals so there is the potential for a far wider variety of intermetallics to be present in a solder joint. These more complex compositions can result in solder joint microstructures that are not as thoroughly studied as current tin-lead solder microstructures. These concerns are magnified by the unintentional use of lead-free solders in either processes designed solely for tin-lead solders or environments where material interactions are poorly understood. For example, the reworking of a tin-lead solder joint with Pb-free solder. These mixed-finish possibilities could negatively impact the solder's reliability.\nAdvantages.\nSAC solders have outperformed high-Pb solders C4 joints in ceramic ball grid array (CBGA) systems, which are ball-grid arrays with a ceramic substrate. The CBGA showed consistently better results in thermal cycling for Pb-free alloys. The findings also show that SAC alloys are proportionately better in thermal fatigue as the thermal cycling range decreases. SAC performs better than Sn-Pb at the less extreme cycling conditions. Another advantage of SAC is that it appears to be more resistant to gold embrittlement than Sn-Pb. In test results, the strength of the joints is substantially higher for the SAC alloys than the Sn-Pb alloy. Also, the failure mode is changed from a partially brittle joint separation to a ductile tearing with the SAC.", "Engineering,_Manufacturing": 1.0000069141, "qwen": "Yes"}
{"id": "63513865", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=63513865", "title": "Markforged", "text": "Markforged is an American public additive manufacturing company that designs, develops, and manufactures The Digital Forge — an industrial platform of 3D printers, software and materials that enables manufacturers to print parts at the point-of-need. The company is headquartered in Waltham, Massachusetts, in the Greater Boston Area. Markforged was founded by Gregory Mark and the chief technology officer (CTO) David Benhaim in 2013. It produced the first 3D printers capable of printing continuous carbon fiber reinforcement and utilizes a cloud architecture.\nHistory.\n2014–2016.\nThe company began as a start-up at SolidWorks World 2014 in San Diego with a working prototype of the \"Mark One\" printer, capable of printing in continuous carbon fiber (the first to do so), fiberglass, nylon and polylactic acid (PLA). Production machines can also print kevlar.\nAt the 2015 Consumer Electronics Show, Markforged unveiled its cloud-based 3D printing software Eiger, which allowed for easier collaboration for a team through a cloud-based workflow process.\n2017.\nAt the 2017 Consumer Electronics Show, Markforged unveiled the Metal X, which is a 3D printer capable of 3D printing metal parts at a low cost, under $100k. The process has been referred to as ADAM (Atomic Diffusion Additive Manufacturing) technology and it has an in-process laser inspection for dimensional accuracy. Metal 3D printers at the time cost between $500,000 and $1 million.\n2018.\nIn March 2018, Markforged was sued by a rival 3D-printer manufacturer, Desktop Metal, which claimed intellectual property theft and patent infringement in regard to methods patented by Desktop Metal involving \"adding layers of an easily removed material to a printed metal product\". A finding in favor of Markforged was rendered in the patent infringement case in July 2018.\n2019.\nIn January 2019, a new UL Standard, 2904, \"ANSI/CAN/UL Standard Method for Testing and Assessing Particle and Chemical Emissions from 3D Printers\", was published Markforged noted in October 2019 that it was pursuing certification against this new standard, claiming that it uses \"a plastic compound that generates lower emissions than many competing machines\". In December 2019, Markforged appointed Shai Terem as president and chief operating officer. Terem joined the team from Kornit Digital, a digital printing company specialising in textiles, where he was president of the Americas region. Terem had previous experience in additive manufacturing, having worked at Stratasys years before.\n2020.\nIn early 2020, Markforged became the first known additive manufacturing platform to achieve ISO/IEC 27001 Certification. ISO/IEC 27001:2013 is an Information Security Management System (ISMS) standard published by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). The certification was applied to Markforged's hardware and Eiger cloud and fleet management software, showing that they meet rigorous international standards in privacy, confidentiality and integrity. In February 2020, the company began to market a 3D-printer system capable of printing pure copper, a version of the company's \"Metal X\" system; the methodology had been in development for some time and involves the use of plastic-encapsulated copper pellets as the raw material.\nDuring the COVID-19 pandemic, Markforged helped to produce over 6,000 face shields in the first three months and partnered with a company called Neurophotometrics to produce Fiberflex Rayon, a 3D printed nasopharyngeal swab for use in diagnostic testing for COVID-19. The effort was renamed Swab56, which developed 55 prototypes over the course of 36 hours before a final design was reached. In October, Markforged announced that Terem was promoted to chief executive officer and president, while the founder Gregory Mark had moved to the role of chairman. The company also announced the launch of The Digital Forge, a cloud-based platform that the company states is the first industrial Additive Manufacturing platform leveraging AI.\n2021–2023.\nIn December 2021, Markforged announced its plans to move to a new corporate headquarters at 60 Tower Rd in Waltham, Massachusetts, to accommodate the company’s growth. The move was planned to be completed in the fall of 2022, and as of February 2023 the new headquarters is currently operational.\nProducts.\nMarkforged offers an additive manufacturing platform called The Digital Forge. The platform combines the company's range of products, which include 3D printers, software and materials, with AI technology. All products are developed and produced in the company's home state of Massachusetts. In order to streamline the development of its systems and ensure quality for the end-user, Markforged manages the full 3D printing development stack in-house. Commercial sales are conducted through an indirect channel of value-added resellers and partners throughout the world.\nMetal 3D printers.\nThe Metal X system produces metal parts using the Atomic Diffusion Additive Manufacturing (ADAM) process - a combination of material extrusion-based additive manufacturing and metal injection molding. \"Green parts\" composed of metal powder and a polymer binder are printed by the Metal X printer. Next, solvent is used to remove a portion of the binder material from the printed parts, leaving \"brown\" parts. Finally, after thermal debinding and sintering, near net-shape metal parts are produced.\nThe system was announced in 2017 and launched in 2018, consisting of the Metal X printer, Wash-1 debinding station, and Sinter-1 furnace. The Metal X printer has a build volume of 300mm x 220mm x 180mm. Available materials on the Metal X system include 17-4PH stainless steel, tool steels (H13, A2, D2), Inconel 625, and pure Copper. In 2019, Markforged released the Sinter-2, a larger furnace with four times the sintering workload of Sinter-1.\nIndustrial composite 3D printers.\nMarkforged industrial composite printers produce parts using a material extrusion process with continuous fiber reinforcement. A dual-extruder system deposits a composite base material to form the shells and infill with the primary nozzle, and using a secondary nozzle, deposits a reinforced filament containing a core of high tensile strength continuous fibers. Because the fibers are contained in a filament, the printer is capable of freely orienting the fibers within the print plane.\nThe X7 (previously called Mark X) was released at the end of 2016 with accuracy improvements, a stiffer gantry, and larger build volume of 330mm x 270mm x 200mm, 2.5 times larger than that of the Mark Two. The printer also has a laser micrometer used for bed leveling and part inspection. In 2017, Markforged announced the X3 and X5 printers on the same chassis with modified hardware. Both machines print using Onyx, and the X5 has the ability to add continuous fiberglass reinforcement.\nDesktop composite 3D printers.\nMarkforged released the first commercial continuous fiber printers in 2014, starting with the Mark One. The printer had an anodized aluminium unibody and the ability to print with strands of continuous carbon fiber.\nThe Mark Two was released in early 2016 as an update to the Mark One. Enhancements include the relocation of the fiber cutter to the print head, motion system improvements, on-printer calibration utilities, and the introduction of a micro carbon fiber filled nylon filament called Onyx.\nBusiness.\nIn July 2013, Markforged raised $1.1 million in seed funding from North Bridge Venture Partners and Matrix Partners and, in May 2014, the company raised $8.5 million in series A funding. By 2017, Markforged has secured investments from Microsoft Ventures, Porsche SE, Tinity Ventures and Siemens-backed Next47 amounting to US$57 million. By 2017, the venture capital firms Matrix Partners, Trinity Ventures and Northbridge Venture Partners had contributed funding as well. By March 2019, Markforged reached funding of US$136.8 million since its founding after raising $82 million in series D funding led by Summit Partners.\nMarkforged's business model is based on the sale of industrial 3D printers to replace traditional metal manufacturing methods, with the prediction that companies will find parallel printing across many machines continuously to be attractive. The company competes with legacy 3D printing companies like Stratasys, 3D Systems and HP, as well as newer startups like Desktop Metal and Carbon.", "Engineering,_Manufacturing": 0.9999667406, "qwen": "Yes"}
{"id": "63513886", "revid": "11498870", "url": "https://en.wikipedia.org/wiki?curid=63513886", "title": "Ingram FBM", "text": "The FBM assault rifle (Fusil Automatico FBM) is an assault rifle manufactured by FBM of Bolivia. The weapon was designed around the IMI Galil and the Stoner 63. The FBM was designed by Gordon Ingram and manufactured by Fabrica Boliviana de Municiones in the 1990s. It was designed for ease of cost/manufacture and with limited equipment such as lathes/mills etc. Although the design uses various combat proven design components, it is not known if the weapon was manufactured and if any more info is available.\nDesign.\nThe FBM assault rifle uses designs from the IMI Galil and the Stoner 63. It uses 5.56x45mm NATO (Galil/STANAG magazines) and 7.62x39mm M43 rounds (AK47 magazines) and exists in Rifle/Carbine/SMG layouts. Components are made from 4130 and 8620 chrome molybdenum heat treated alloy steel for durability. The bolt is enclosed in a one piece receiver attached to an inline barrel to the bore with the cocking handle at the rear to resist overheating. Weapon when fired using a roller hammer. Field stripping of the bolt is at the rear of the upper receiver allowing the secure low profile use of sights etc. low mounted on the receiver. The FBM also uses a fixed stock as well as FN/Galil side folding stock, bipod, bayonet, grenade launchers and electrical fire controls. Designed for ease of manufacture in facilities with limited equipment/resources, the basic structural components/lockwork are pressed sheet stampings with simplified outlines and contours for in house modular design. However, only the bolt and gas components are manufactured on lathes/mills.\nThe fire control group of the FBM has 3 positions: Forward position allows full auto, Middle allows semi auto, Rear allows safety. When field stripping, press down rear tab of the recoil spring guide at the rear of the upper receiver and hinge open forward (holding rear tab of the recoil spring guide). This would allow the recoil spring guide and bolt group to be removed from the upper receiver.", "Engineering,_Manufacturing": 0.9986206293, "qwen": "Yes"}
{"id": "63520855", "revid": "46389383", "url": "https://en.wikipedia.org/wiki?curid=63520855", "title": "Attabotics", "text": "Attabotics is a robotics company based in Calgary, Alberta, Canada that specializes in Automated Storage and Retrieval System (AS/RS) inventory management systems. Founded in 2016, the company designs and manufactures intelligent robots that operate within a modular, three-dimensional storage structure that minimizes the traditional fulfillment center footprint.\nOrigins.\nThe Attabotics system grew out of a thought experiment about what an automated warehouse designed specifically for robots might look like. After exploring multiple designs, founder Scott Gravelle took inspiration from the natural world:The original inspiration for the company was the leaf-cutter ant, whose Latin name is ‘Atta’… I saw a documentary where a researcher had poured molten aluminum down an ant colony and then dug it up. Ants integrate goods vertically.\n—Scott Gravelle, Attabotics Founder, CEO, CTO\nTechnology.\nAttabotics’ proprietary 3D storage system, The Studio, combines order picking, packing, and shipping into one consolidated solution. This differs significantly from many existing robotics fulfillment models, which frequently do not incorporate sortation into the solution infrastructure.\nThe Studio consists of four interconnected systems:\nAlthough the first generation of Attabotics solutions utilized existing technologies to deliver a proof-of-concept and pilot model, later designs incorporate several proprietary designs developed specifically for the company’s innovative fulfillment solution. Combining hardware, software, and process development under one roof not only allowed Attabotics to build a more efficient system, but also to apply those efficiencies to the production process to improve productivity and minimize overhead costs.\nHistory.\n2016.\nAttabotics is founded by Scott Gravelle to capitalize on emerging opportunities in the growing AS/RS robotics market.\n2017.\nThe first prototype 3d storage system is developed as a proof of concept. Alberta Innovates, a government agency designed to help start-ups bridge the gap between concept and working prototype, makes a key early investment in the company.\n2018.\nAttabotics announces development of new manufacturing site at Calgary’s YYC Global Logistics Park in partnership with Opportunity Calgary Investment Fund. The deal ensures that both development and production will remain in Canada. Attabotics also begins its partnership with Gordon Food Service, one of North America’s largest foodservice distributors to automate elements of its supply chain.\n2019.\nThe company announces plans to build new headquarters in Calgary and hires one of Canada’s leading architectural firms to design the building. A new partnership with Microsoft is established to expand edge computing, LTE networking, and IoT capabilities.\n2020.\nInvestments from the Canadian government as part of the country's Innovation, Science and Economic Development portfolio allows Attabotics to expand its research and manufacturing operations in Canada.\n2021.\nAttabotics pushes to expand its capabilities by partnering with Canada’s leading artificial intelligence (AI) and machine learning (ML) companies. In May, the company announces a partnership with AltaML and the Alberta Machine Intelligence Institute (Amii) to improve supply chain efficiencies. Canada’s SCALE AI also announces that it will invest in Attabotics as part of an Artificial Intelligence of Things (AIoT) initiative to further improve fulfillment efficiency, uptime, and throughput.\n2022.\nAn agreement with SYNUS Tech allows the company to expand operations into the South Korean market. It also partners with Körber Supply Chain to bring its automation technology to the EU. Attabotics is also selected by the US Department of Defense as robotics provider for the Marine Corps Logistics Command 5G ‘Smart Warehouse.’\nThe company continues to build relationships with Canadian firms. In July, it establishes a new partnership with Modern Beauty, Canada’s leading beauty retailer, to introduce automation technology to Calgary-area fulfillment center. Another deal is struck to help Pan Pacific Pet modernize its warehouse operations.\nAttabotics expands its leadership team by hiring tech industry veteran Richard Cheung as Chief Financial Officer (CFO).", "Engineering,_Manufacturing": 0.9985005856, "qwen": "Yes"}
{"id": "9926926", "revid": "176575", "url": "https://en.wikipedia.org/wiki?curid=9926926", "title": "Microfactory", "text": "A microfactory either refers to a capital-light facility used for the local assembly of a complex product or system or a small (normally automated) factory for producing small quantities of products. The term was proposed by the Mechanical Engineer Laboratory (MEL) of Japan in 1990 and has recently been used to describe the approach of manufacturers like Arrival. The microfactory's main advantages are saving a substantial amount of space, energy, materials, time, and upfront capital costs. \nDue to their reduced dimensions, microfactories are normally highly automated. They might contain automatic machine tools, assembly systems, quality inspection systems, material feed systems, waste elimination systems, a system to evaluate tool deterioration and a system to replace tools.\nAt least one proposed microfactory is being designed to make many of its own parts, i.e., a partially self-replicating machine.\nA microfactory can also refer to a factory designed for flexible small batch production that can produce a wide variety of products as opposed to a single monolithic mass production type approach. Typically the manufacturing processes of microfactories take advantage of digital fabrication technology such as 3D printing and CNC machines in order to accomplish this. For example, Local Motors had microfactories in Phoenix, Ariz. and Knoxville, Tenn. The company built products, like the Rally Fighter prerunner sports car, in its microfactories.", "Engineering,_Manufacturing": 1.0000083447, "qwen": "Yes"}
{"id": "7710805", "revid": "40123752", "url": "https://en.wikipedia.org/wiki?curid=7710805", "title": "Packaging engineering", "text": "Packaging engineering, also package engineering, packaging technology and packaging science, is a broad topic ranging from design conceptualization to product placement. All steps along the manufacturing process, and more, must be taken into account in the design of the package for any given product. Package engineering is an interdisciplinary field integrating science, engineering, technology and management to protect and identify products for distribution, storage, sale, and use. It encompasses the process of design, evaluation, and production of packages. It is a system integral to the value chain that impacts product quality, user satisfaction, distribution efficiencies, and safety. Package engineering includes industry-specific aspects of industrial engineering, marketing, materials science, industrial design and logistics. Packaging engineers must interact with research and development, manufacturing, marketing, graphic design, regulatory, purchasing, planning and so on. The package must sell and protect the product, while maintaining an efficient, cost-effective process cycle.\nEngineers develop packages from a wide variety of rigid and flexible materials. Some materials have scores or creases to allow controlled folding into package shapes (sometimes resembling origami). Packaging involves extrusion, thermoforming, molding and other processing technologies. Packages are often developed for high speed fabrication, filling, processing, and shipment. Packaging engineers use principles of structural analysis and thermal analysis in their evaluations.\nEducation.\nSome packaging engineers have backgrounds in other science, engineering, or design disciplines while some have college degrees specializing in this field.\nFormal packaging programs might be listed as package engineering, packaging science, packaging technology, etc. BE, BS, MS, M.Tech and PhD programs are available. Students in a packaging program typically begin with generalized science, business, and engineering classes before progressing into industry-specific topics such as shelf life stability, corrugated box design, cushioning, engineering design, labeling regulations, project management, food safety, robotics, RFID tags, quality management, package testing, packaging machinery, tamper-evident methods, recycling, computer-aided design, etc.", "Engineering,_Manufacturing": 0.9999917746, "qwen": "Yes"}
{"id": "10119206", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=10119206", "title": "Buchli drive", "text": "The Buchli drive is a transmission system used in electric locomotives. It was named after its inventor, Swiss engineer Jakob Buchli. The drive is a fully spring-loaded drive, in which each floating axle has an individual motor, that is placed in the spring mounted locomotive frame. The weight of the driving motors is completely disconnected from the driving wheels, which are exposed to movement of the rails.\nFirst used in electric locomotives from the 1920s, the Buchli drive made possible the construction of faster and more powerful locomotives that required larger and heavier traction motors. The system minimises the impact on rail tracks due to the reduction in the overall unsprung weight. Although the drive was very successful though the 1930s, it is little used in modern locomotives, having been replaced with smaller, simpler drives that exhibit less imbalance and allow higher speeds.\nConstruction.\nIn a Buchli drive a driven gear wheel is securely fixed to the locomotive frame. Inside this gear wheel are two levers, coupled to gear segments that mesh with one another. The other end of the levers is coupled via universal joints to tension bars, which are then coupled via more universal joints to the driving rail wheel.\nVertical movement of the driving wheel results in the gear segments moving due to the internal mechanism, and the driving wheel can move in a horizontal or vertical direction with respect to the gear wheel, while still transferring the momentum of the gear wheel.\nA disadvantage of the drive was the large number of moving parts, which demanded frequent lubrication and careful maintenance. As a result the Buchli drive system was mainly used on express train locomotives, as there were no other drive systems that gave the same performance at high speeds. However, at higher speeds the drive components became unbalanced, causing issues at speeds over 140 km per hour.\nStandard design.\nThe Buchli drive was exported to other rail companies as one sided separate traction motor drive, usually with an inside frame.\nThe motor framework with the wheelset bearing is located between the wheel disks of the driving wheels. The gear wheel, which is housed in an auxiliary frame outside the driving wheels and is surrounded by a protective casing, is on one side of the driving wheels. Each gear wheel is driven by an individual traction motor, which is located above the gear wheel in the locomotive body.\nWith this implementation, a strongly one-sided weight distribution occurs in the underframe through the remote gear wheels. In order to maintain stability of the locomotive on the longitudinal axis, heavy equipment inside the locomotive body must be arranged on the opposite side of the drive equipment.\nLocomotives with a Buchli drive also typically have an asymmetrical appearance: on one side, the bearings of the drive wheels are visible, on the other side, they are almost completely covered by the wheel cover box of the gear wheels.\nOther designs.\nIn addition to the standard implementation, there were also the following variations:\nOutside frame.\nThe engine framework with the driving wheel housing is outside the wheel disks of the driving wheels. The driving wheel is enclosed by a quill camped in the locomotive cabinet, on which the gear wheel sits. Examples included the Pennsylvania Railroad O1b, and the Deutsche Reichsbahn ET11.01.\nGroup drive.\nThe motor is arranged between the floating axles. A common pinion or a pinion on both motor end drives the gear wheels of the neighbouring axes. described this design, but vehicles implementing it are not known.\nBilateral drive.\nThe driving wheel is coupled with two gear wheels, and the motor has a pinion on both sides. The taps in the wheel disk are warped about 90 degrees against each other so that the drive imbalance can be reduced. This version of the driver was used for greater driving power.\nHowever with this arrangement, there is the danger of mechanical stress in the drive components. Examples included the French express train locomotives: SNCF 2D2 5400, SNCF 2D2 5500, SNCF 2D2 9100.\nTwo motors per axis.\nTwo driving motors work on one common gear wheel, which is interconnected with a driving wheel. Examples include the Pennsylvania Railroad O1b.\nLocomotive with Buchli drive.\nNearly 240 locomotives of the SBB with Buchli drive were in use for over sixty years. The SBB Ae 3/6I class locomotives were in operation from 1921 to 1994. French tracks had 100 express train locomotives using the Buchli drive, in service for fifty years.", "Engineering,_Manufacturing": 0.9996726513, "qwen": "Yes"}
{"id": "35632900", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=35632900", "title": "Lapping film", "text": "Lapping film, in telecommunications, is a precision coated abrasive consumable mainly used for processing and polishing optical fiber connectors. It is made from a polyester base sheet, coated with precisely graded minerals such as diamond, aluminium oxide, silicon carbide, silicon oxide or cerium oxide. Lapping film is designed to provide a uniform, consistent finish on optical fiber connector end tips to ensure efficient light/signal transmission. It is available in 0.01-45 μm grades, with or without pressure-sensitive adhesive (PSA) backing.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "51171315", "revid": "44656042", "url": "https://en.wikipedia.org/wiki?curid=51171315", "title": "Expanded polyethylene", "text": "Expanded polyethylene (aka EPE foam) refers to foams made from polyethylene. Typically it is made from expanded pellets ('EPE bead') made with use of a blowing agent, followed by expansion into a mold in a steam chest - the process is similar to that used to make expanded polystyrene foam.\nProperties.\nEPE foams are low density, semi-rigid, closed cell foam that are generally somewhere in stiffness/compliance between Expanded polystyrene and Polyurethane. Production of EPE foams is similar to that of expanded polystyrene, but starting with PE beads. Typical densities are with the lower figure being common. Densities as low as can be produced.\nBase polymer for EPE foams range from Low-density polyethylene (LDPE) to High-density polyethylene (HDPE).\nCo-polymers.\nExpanded polyethylene copolymers (EPC) are also known - such as 50:50 (weight) materials with polystyrene. Though other properties are intermediate between the two bases, toughness for the copolymer exceeds either, with good tensile and puncture resistance. It is particularly applicable for re-usable products.\nProduction.\nEPE foams were first manufactured in the 1970s.\nProduction of the PE beads is usually by extrusion, followed by chopping, producing a 'pellet'. Autoclave expansion is the most common route the bead foam. Butane or pentane is often used as a blowing agent (before 1992 CFCs may have been used). Depending on the specific process uses the beads may be cross-linked either by electron beam irradiation (see Electron beam processing), or by the addition of a chemical agent such as Dicumyl peroxide.\nAn alternate route (JSP Process) to the beads uses carbon dioxide as a blowing agent which is impregnated into the pellets in an autoclave at a temperature close to the plastic's crystalline melting point. The pellets are foamed by \"flashing\" into the (lower pressure) atmosphere to expand.\nFinally molding is done by steam chest compression molding; usually the low pressure variant of the process is used, though the high pressure variant may be used for HDPE based EPE foams.\nUses.\nPolyethylene bead foams (including) EPE can be used to replace both polystyrene foam, and both rigid and flexible polyurethane. Uses include cushioning applications, and impact absorption applications including packaging.\nConsumption of polyethylene for PE foam was estimated at 114x106 kg in 2001. The majority was used for non-crosslinked foams, but crosslinked PE foams represented a significant (~ one third) fraction of demand. Use in protective packaging represented the largest use sector for such foams.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "51172574", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=51172574", "title": "RepRap Snappy", "text": "The RepRap Snappy is an open-source fused deposition modeling 3D printer, part of the RepRap project, it is the most self replicating 3D printer in the world.\nThe RepRap Snappy is designed to address the core goal of the RepRap project of creating a \"'general-purpose self-replicating manufacturing machine\"'. The RepRap Snappy is able to create 73% of its own parts by volume with a design that eliminates as many of the non 3D printed parts as possible including belts and bearings which are replaced with a rack and pinion system. The name Snappy comes from the use of snap fit connectors used on the small printed parts to construct larger pieces, this both cuts down on the use of non 3D printed parts and means a smaller build volume is needed on the machine producing the parts. The only non self replicating parts on the printer are the motors, electronics, a glass build plate and one 686 bearing, the 3D printed parts take around 150 hours to create. The RepRap Snappy received an honourable mention in the Uplift Prize Grand Personal Manufacturing Prize.", "Engineering,_Manufacturing": 0.9999966621, "qwen": "Yes"}
{"id": "23756855", "revid": "1156319068", "url": "https://en.wikipedia.org/wiki?curid=23756855", "title": "Severe plastic deformation", "text": "Severe plastic deformation (SPD) is a generic term describing a group of metalworking techniques involving very large strains typically involving a complex stress state or high shear, resulting in a high defect density and equiaxed \"ultrafine\" grain (UFG) size (d nanocrystalline (NC) structure (d < 100 nm).\nHistory.\nThe significance of SPD was known from the ancient times, at least during the transition from the Bronze Age to the Iron Age, when repeated hammering and folding was employed for processing strategic tools such as swords. The development of the principles underlying SPD techniques goes back to the pioneering work of P.W. Bridgman at Harvard University in the 1930s. This work concerned the effects on solids of combining large hydrostatic pressures with concurrent shear deformation and it led to the award of the Nobel Prize in Physics in 1946. Very successful early implementations of these principles, described in more detail below, are the processes of equal-channel angular pressing (ECAP) developed by V.M. Segal and co-workers in Minsk in the 1970s and high-pressure torsion, derived from Bridgman's work, but not widely developed until the 1980s at the Russian Institute of Metals Physics in modern-day Yekaterinburg.\nSome definitions of SPD describe it as a process in which high strain is applied without any significant change in the dimensions of the workpiece, resulting in a large hydrostatic pressure component. However, the mechanisms that lead to grain refinement in SPD are the same as those originally developed for mechanical alloying, a powder process that has been characterized as \"severe plastic deformation\" by authors as early as 1983. Additionally, some more recent processes such as asymmetric rolling, do result in a change in the dimensions of the workpiece, while still producing an ultrafine grain structure. The principles behind SPD have even been applied to surface treatments.\nMethods.\nEqual channel angular Pressing.\nEqual channel angular extrusion (ECAE, sometimes called Equal channel angular pressing, ECAP) was developed in the 1970s. In this process, a metal billet is pressed through an angled (typically 90 degrees) channel. To achieve optimal results, the process may be repeated several times, changing the orientation of the billet with each pass. This produces a uniform shear throughout the bulk of the material.\nHigh pressure torsion.\nHigh pressure torsion (HPT) can be traced back to the experiments that won Percy Bridgman the 1946 Nobel Prize in Physics, though its use in metal processing is considerably more recent. In this method, a disk of the material to be strained is placed between 2 anvils. A large compressive stress (typically several gigapascals) is applied, while one anvil is rotated to create a torsion force. HPT can be performed unconstrained, in which the material is free to flow outward, fully constrained, or to some degree between in which outward flow is allowed, but limited.\nAccumulative roll bonding.\nIn accumulative roll bonding (ARB), 2 sheets of the same material are stacked, heated (to below the recrystallization temperature), and rolled, bonding the 2 sheets together. This sheet is cut in half, the 2 halves are stacked, and the process is repeated several times. Compared to other SPD processes, ARB has the benefit that it does not require specialized equipment or tooling, only a conventional rolling mill. However, the surfaces to be joined must be well-cleaned before rolling to ensure good bonding.\nRepetitive corrugation and straightening.\nRepetitive corrugation and straightening (RCS) is a severe plastic deformation technique used to process sheet metals. In RCS, a sheet is pressed between two corrugated dies followed by pressing between two flat dies. RCS has gained wide popularity to produce fine grained sheet metals. Endeavors to improve this technique lead to introduce Repetitive Corrugation and Straightening by Rolling (RCSR), a novel SPD method. Applicability of this new method approved in the various materials.\nAsymmetric rolling.\nIn asymmetric rolling (ASR), a rolling mill is modified such that one roll has a higher velocity than the other. This is typically done with either independent speed control or by using rolls of different size. This creates a region in which the frictional forces on the top and bottom of the sheet being rolled are opposite, creating shear stresses throughout the material in addition to the normal compressive stress from rolling. Unlike other SPD processes, ASR does not maintain the same net shape, but the effect on the microstructure of the material is similar.\nMechanical alloying.\nMechanical alloying/milling (MA/MM) performed in a high-energy ball mill such as a shaker mill or planetary mill will also induce severe plastic deformation in metals. During milling, particles are fractured and cold welded together, resulting in large deformations. The end product is generally a powder that must then be consolidated in some way (often using other SPD processes), but some alloys have the ability to consolidate \"in-situ\" during milling. Mechanical alloying also allows powders of different metals to be alloyed together during processing.\nSurface treatments.\nMore recently, the principles behind SPD have been used to develop surface treatments that create a nanocrystalline layer on the surface of a material. In the surface mechanical attrition treatment (SMAT), an ultrasonic horn is connected to an ultrasonic (20 kHz) transducer), with small balls on top of the horn. The workpiece is mounted a small distance above the horn. The high frequency results in a large number of collisions between the balls and the surface, creating a strain rate on the order of 102–103 s−1. The NC surface layer developed can be on the order of 50 μm thick. The process is similar to shot peening, but the kinetic energy of the balls is much higher in SMAT.\nAn ultrasonic nanocrystalline surface modification (UNSM) technique is also one of the newly developed surface modification technique. In the UNSM process, not only the static load, but also the dynamic load are exerted. The processing is conducted striking a workpiece surface up to 20K or more times per second with shots of an attached ball to the horn in the range of 1K-100K per square millimeter. The strikes, which can be described as cold-forging, introduce SPD to produce a NC surface layer by refining the coarse grains until nanometer scale without changing the chemical composition of a material which render the high strength and high ductility. This UNSM technique does not only improve the mechanical and tribological properties of a material, but also produces a corrugated structure having numerous of desired dimples on the treated surface.\nApplications.\nMost research into SPD has focused on grain refinement, which has obvious applications in the development of high-strength materials as a result of the Hall-Petch relation. Conventionally processed industrial metals typically have a grain size from 10–100 μm. Reducing the grain size from 10 μm to 1 μm can increase the yield strength of metals by more than 100%. Techniques that use bulk materials such as ECAE can provide reliable and relatively inexpensive ways of producing ultrafine grain materials compared to rapid solidification techniques such as melt spinning.\nHowever, other effects of SPD, such as texture modification also have potential industrial applications as properties such as the Lankford coefficient (important for deep drawing processes) and magnetic properties of electrical steel are highly dependent on texture.\nProcesses such as ECAE and HPT have also been used to consolidate metal powders and composites without the need for the high temperatures used in conventional consolidation processes such as hot isostatic pressing, allowing desirable characteristics such as nanocrystalline grain sizes or amorphous structures to be retained.\nSome known commercial application of SPD processes are in the production of Sputtering targets by Honeywell and UFG titanium for medical implants.\nGrain refinement mechanism.\nThe presence of a high hydrostatic pressure, in combination with large shear strains, is essential for producing high densities of crystal lattice defects, particularly dislocations, which can result in a significant refining of the grains. Grain refinement in SPD processes occurs by a multi-step process:\nThe mechanism by which the subgrains rotate is less understood. Wu \"et al.\" describe a process in which dislocation motion becomes restricted due to the small subgrain size and grain rotation becomes more energetically favorable. Mishra \"et al.\" propose a slightly different explanation, in which the rotation is aided by diffusion along the grain boundaries (which is much faster than through the bulk).\nF.A. Mohamad has proposed a model for the minimum grain size achievable using mechanical milling. The model is based on the concept that the grain size is dependent on the rates at which dislocations are generated and annihilated. The full model is given by\nformula_1\nWhile the model was developed specifically for mechanical milling, it has also been successfully applied to other SPD processes. Frequently only a portion of the model is used (typically the term involving the stacking fault energy) as the other terms are often unknown and difficult to measure. This is still useful as it implies that all other things remaining equal, reducing the stacking fault energy, a property that is a function of the alloying elements, will allow for better grain refinement. A few studies, however, suggested that despite the significance of stacking fault energy on the grain refinement at the early stages of straining, the steady-state grain size at large strains is mainly controlled by the homologous temperature in pure metals and by the interaction of solute atoms and dislocations in single-phase alloys.", "Engineering,_Manufacturing": 0.9999812841, "qwen": "Yes"}
{"id": "44501478", "revid": "20611691", "url": "https://en.wikipedia.org/wiki?curid=44501478", "title": "Roll bonding", "text": "Roll bonding is a solid state, cold welding process, obtained through flat rolling of sheet metals. In roll bonding, two or more layers of different metals are passed through a pair of flat rollers under sufficient pressure to bond the layers. The pressure is high enough to deform the metals and reduce the combined thickness of the clad material. The mating surfaces must be previously prepared (scratched, cleaned, degreased) in order to increase their friction coefficient and remove any oxide layers.\nThe process can be performed at room temperature or at warm conditions. In warm roll bonding, heat is applied to pre-heat the sheets just before rolling, in order to increase their ductility and improve the strength of the weld. The strength of the rolled bonds depends on the main process parameters, including the rolling conditions (entry temperature of the sheets, amount of thickness reduction, rolling speed, etc.), the pre-rolling treatment conditions (annealing temperature and time, surface preparation techniques, etc.) and the post-rolling heat treatments.\nApplications.\nThe applications of roll bonding can be used for cladding of metal sheets, or as a sub-step of the accumulative roll bonding. Bonding of the sheets can be controlled by painting a pattern on one sheet; only the bare metal surfaces bond, and the un-bonded portion can be inflated if the sheet is heated and the coating vaporizes. This is used to make heat exchangers for refrigeration equipment. ", "Engineering,_Manufacturing": 1.0000025034, "qwen": "Yes"}
{"id": "44508450", "revid": "44267563", "url": "https://en.wikipedia.org/wiki?curid=44508450", "title": "Production control", "text": "Within supply chain management and manufacturing, production control is the activity of monitoring and controlling any particular production or operation. Production control is often run from a specific control room or operations room. With inventory control and quality control, production control is one of the key functions of operations management.\nOverview.\nProduction control is the activity of monitoring and controlling a large physical facility or physically dispersed service. It is a \"set of actions and decision taken during production to regulate output and obtain reasonable assurance that the specification will be met.\" The American Production and Inventory Control Society, nowadays APICS, defined production control in 1959 as:\nProduction planning and control in larger factories is often run from a production planning department run by production controllers and a production control manager. Production monitoring and control of larger operations is often run from a central space, called a control room or operations room or operations control center (OCC).\nThe emerging area of Project Production Management (PPM), based on viewing project activities as a production system, adopts the same notion of production control to take steps to regulate the behavior of a production system where in this case the production system is a capital project, rather than a physical facility or a physically dispersed service.\nProduction control is to be contrasted with project controls. As explained, project controls have developed to become centralized functions to track project progress and identify deviations from plan and to forecast future progress, using metrics rooted in accounting principles.\nTypes.\nOne type of production control is the control of manufacturing operations. \nManagement of real-time operational in specific fields. \nCommunist countries had a central production control institute, where the agricultural and industrial production for the whole nation was planned and controlled.\nIn Customer Care environments production control is known as Workforce Management (WFM). Centralized Workforce Management teams are often called Command Center, Mission Control or WFM Shared Production Centers.\nRelated types of control in organizations.\nProduction control is just one of multiple types of control in organizations. Most commons other types are:", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "44525303", "revid": "1023297459", "url": "https://en.wikipedia.org/wiki?curid=44525303", "title": "Rotary transfer machine", "text": "A rotary transfer machine is a machine tool, typically for metal working by machining, comprising a large indexing table with machining stations surrounding the table. Such rotary transfer machines are used for producing a large number of parts in fairly short cycle times.\nOperation.\nIn rotary transfer machines, the workpieces are located and clamped in pallet type fixtures that are indexed in a circular path. During one cycle, sequential machining operations are performed simultaneously on the workpieces. The indexed table turns vertically or horizontally, and its movement could be continuous or intermittent. As the indexing table turns, the subsequent machining operation is repeated on the workpiece which was just machined by the previous station. This design combines automated part feed with simultaneous operations, enabling rapid completion of parts.\nApplications.\nRotary transfer machines are commonly used for the mass-production of metal parts in the automotive industry and for pneumatic and hydraulic fittings. The parts can range from simple to complex, depending on the layout of the machining tool, which is often custom-designed for the manufacturing of a single part or family of parts. Rotary arrangement presents a compact arrangement that saves floor space. The annual production capacity of one rotary transfer machine can range from 100'000 units to tens of millions of units.\nRotary transfer machines can generally cope with all standard machining operations like turning, milling, drilling, reaming, threading, recessing, marking, deburring, etc... for sizes ranging more or less from a fingernail up to a backpack. ", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "16950200", "revid": "25545329", "url": "https://en.wikipedia.org/wiki?curid=16950200", "title": "Retaining ring", "text": "A retaining ring is a fastener that holds components or assemblies onto a shaft or in a housing/bore when installed - typically in a groove - for one time use only. Once installed, the exposed portion acts as a shoulder which retains the specific component or assembly. Circlips are a type of retaining ring.\nCircular push-on retaining rings may be installed in applications where there is no groove.\nRetaining rings are typically made from carbon steel, stainless steel or beryllium copper and may feature a variety of finishes for aesthetics and corrosion protection depending on the type of environment in which they are used.\nTypes.\nThere are four main types of retaining rings available, each of which may then be broken down into sub-types depending on unique application needs:\nTapered section retaining rings.\nTapered section retaining rings decrease symmetrically from the center to the free ends, remaining circular when contracted or expanded within the limits of normal use. This assures contact with the groove along the entire periphery of the ring. These rings may be installed axially (horizontally along the center point of an axis) or radially (externally along the radius of a circle). Depending on the size of the ring in question, it may be manufactured in one of two ways: \nAxially assembled.\nAxially assembled retaining rings are installed into machined grooves in housings/bores (internal) or on shafts (external). These rings are manufactured with lug holes—small holes in the lugs of both axial internal and external retaining rings—that are used to install/remove them, using pliers designed for this purpose.\nInverted retaining rings.\nInverted retaining rings are a variation of axially assembled rings in which the lug holes are inverted to fit in the bottom of the groove. Inverting the lugs allows greater clearance on a shaft or in a housing and forms a higher uniform shoulder good for retaining bearings and other components with large corner radii or chamfers.\nBeveled retaining rings.\nBeveled retaining rings feature a 15° beveled or angled edge. This angle allows the ring to wedge itself between the groove and the retained part until it can go no farther, effectively “locking” everything in place. Think of placing a cork in a bottle. The cork is forced into the opening until it is wedged as far into the opening as possible. The same thing happens when a beveled retaining ring is installed into an application. The ring is wedging itself into place between the groove wall and the retained part, resulting in what is referred to as rigid end-play take-up.\nBowed retaining rings.\nBowed retaining rings are curved versions of standard flat internal and external retaining rings and exert a pre-load on an assembly when installed in the groove. This takes up the end-play and acts like a spring, which keeps the assembly in compression.\nIn manufacturing, parts can not be produced to an exact dimension; as a result, if they are made on the low side of the tolerance, they will be loose or have play on the shaft when a standard ring is installed. If they are made on the high side of the tolerance, they will extend further into the groove and prevent a standard ring from being fully installed. Compensating for accumulated tolerances is what bowed retaining rings are designed to do, by acting as a spring once installed into the groove.\nRadially assembled.\nRadially assembled retaining rings are installed externally into machined grooves on a shaft. These rings have no lug holes and must be installed using applicators.\nSelf-locking.\nSelf-locking retaining rings can be installed in a housing/bore or on a shaft that has not had a groove machined into it. Self-locking rings with no lug holes are impossible to remove without either destroying the ring or warping it out of specified tolerances.\nConstant section retaining rings.\nConstant section retaining rings (snap rings) feature a uniform, constant section. In other words, the material used to make the ring is the same width at any point along the circumference of the ring. When they are contracted or expanded, they take on an elliptical deformation. As a result, they contact the groove at three or more isolated points but never continuously around the periphery. These rings are made from either flat or round wire.\nSpiral retaining rings.\nSpiral retaining rings are axially installed into housings/bores (internal) or onto shafts (external), making 360° contact with the groove. Spiral retaining rings have no ears or lugs to interfere with the assembly. These rings are manufactured by coiling flat wire into the shape of the finished retaining ring. Spiral rings are provided with a removal notch to simplify the removal process. Spiral retaining rings can be economically produced in special alloys like stainless steel because the manufacturing process eliminates scrap.\nNo special tools are required for installation or removal. Duck bill pliers can be used in installing and removing external spiral rings.\nCircular push-on.\nA circular push-on ring resembles a toothed washer, commonly fabricated in metal. These are installed by pressing onto the end of a grooved shaft, until the nut's inner teeth snap into the groove. The use of push nuts avoids the cost of threading a nut onto the end of the shaft during the manufacturing process.\nProtective finishes.\nThe following are various surface finished used on retaining rings:", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "1005128", "revid": "5174031", "url": "https://en.wikipedia.org/wiki?curid=1005128", "title": "Wave soldering", "text": "Wave soldering is a bulk soldering process used for the manufacturing of printed circuit boards. The circuit board is passed over a pan of molten solder in which a pump produces an upwelling of solder that looks like a standing wave. As the circuit board makes contact with this wave, the components become soldered to the board. Wave soldering is used for both through-hole printed circuit assemblies, and surface mount. In the latter case, the components are glued onto the surface of a printed circuit board (PCB) by placement equipment, before being run through the molten solder wave. Wave soldering is mainly used in soldering of through hole components.\nAs through-hole components have been largely replaced by surface mount components, wave soldering has been supplanted by reflow soldering methods in many large-scale electronics applications. However, there is still significant wave soldering where surface-mount technology (SMT) is not suitable (e.g., large power devices and high pin count connectors), or where simple through-hole technology prevails (certain major appliances).\nWave solder process.\nThere are many types of wave solder machines; however, the basic components and principles of these machines are the same. The basic equipment used during the process is a conveyor that moves the PCB through the different zones, a pan of solder used in the soldering process, a pump that produces the actual wave, the sprayer for the flux and the preheating pad. The solder is usually a mixture of metals. A typical leaded solder is composed of 50% tin, 49.5% lead, and 0.5% antimony. The Restriction of Hazardous Substances Directive (RoHS) has led to an ongoing transition away from 'traditional' leaded solder in modern manufacturing in favor of lead-free alternatives. Both tin-silver-copper and tin-copper-nickel alloys are commonly used, with one common alloy (SN100C) being 99.25% tin, 0.7% copper, 0.05% nickel and <0.01% germanium.\nFluxing.\nFlux in the wave soldering process has a primary and a secondary objective. The primary objective is to clean the components that are to be soldered, principally any oxide layers that may have formed. There are two types of flux, corrosive and noncorrosive. Noncorrosive flux requires precleaning and is used when low acidity is required. Corrosive flux is quick and requires little precleaning, but has a higher acidity.\nPreheating.\nPreheating helps to accelerate the soldering process and to prevent thermal shock.\nCleaning.\nSome types of flux, called \"no-clean\" fluxes, do not require cleaning; their residues are benign after the soldering process. Typically no-clean fluxes are especially sensitive to process conditions, which may make them undesirable in some applications. Other kinds of flux, however, require a cleaning stage, in which the PCB is washed with solvents and/or deionized water to remove flux residue.\nFinish and quality.\nQuality depends on proper temperatures when heating and on properly treated surfaces.\nSolder types.\nDifferent combinations of tin, lead and other metals are used to create solder. The combinations used depend on the desired properties. The most popular combinations are SAC (Tin(Sn)/Silver(Ag)/Copper(Cu)) alloys for lead-free processes and Sn63Pb37 (Sn63A) which is a eutectic alloy consisting of 63% tin and 37% lead. This latter combination is strong, has a low melting range, and melts and sets quickly (i.e., no 'plastic' range between the solid and molten states like the older 60% tin / 40% lead alloy). Higher tin compositions give the solder higher corrosion resistances, but raise the melting point. Another common composition is 11% tin, 37% lead, 42% bismuth, and 10% cadmium. This combination has a low melting point and is useful for soldering components that are sensitive to heat.\nEnvironmental and performance requirements also factor into alloy selection. Common restrictions include restrictions on lead (Pb) when RoHS compliance is required and restrictions on pure tin (Sn) when long term reliability is a concern.\nEffects of cooling rate.\nIt is important that the PCBs be allowed to cool at a reasonable rate. If they are cooled too fast, then the PCB can become warped and the solder can be compromised. On the other hand, if the PCB is allowed to cool too slowly, then the PCB can become brittle and some components may be damaged by heat. The PCB should be cooled by either a fine water spray or air cooled to decrease the amount of damage to the board.\nThermal profiling.\nThermal profiling is the act of measuring several points on a circuit board to determine the thermal excursion it takes through the soldering process.\nIn the electronics manufacturing industry, SPC (Statistical Process Control) helps determine if the process is in control, measured against the reflow parameters defined by the soldering technologies and component requirements.\nProducts like the Solderstar WaveShuttle and the Optiminer have been developed special fixtures which are passed through the process and can measure the temperature profile, along with contact times, wave parallelism and wave heights. These fixture combined with analysis software allows the production engineer to establish and then control the wave solder process.\nSolder wave height.\nThe height of the solder wave is a key parameter that needs to be evaluated when setting up the wave solder process. The contact time between the solder wave and assembly being soldered is typically set to between 2 and 4 seconds. This contact time is controlled by two parameters on the machine, conveyor speed and wave height, changes to either of these parameters will result in a change in contact time. The wave height is typically controlled by increasing or decreasing the pump speed on the machine. Changes can be evaluated and checked using a tempered glass plate, if more detailed recording are required fixture are available which digitally record the contact times, height and speed. Also, some wave solder machines can give the operator a choice between a smooth laminar wave or a slightly higher-pressure 'dancer' wave.", "Engineering,_Manufacturing": 0.9999961853, "qwen": "Yes"}
{"id": "43163841", "revid": "19244234", "url": "https://en.wikipedia.org/wiki?curid=43163841", "title": "Maurer-Union", "text": "Maurer-Union was a German car maker located in Nuremberg. From 1900-1910 Maurer-Union produced 300 to 400 cars per year. It was one of the first manufacturers that introduced continuously variable transmission using a friction drive.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "43165567", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=43165567", "title": "Reusable packaging", "text": "Reusable packaging is manufactured of durable materials and is specifically designed for multiple trips and extended life. A \"reusable package\" or container is \"designed for reuse without impairment of its protective function.\" The term returnable is sometimes used interchangeably but it can also include returning packages or components for other than reuse: recycling, disposal, incineration, etc. Typically, the materials used to make returnable packaging include steel, wood, polypropylene sheets or other plastic materials.\nReusability of packaging is an important consideration of the environmental credo of \"reduce, reuse, and recycle\". It is also important to the movement toward more sustainable packaging. Returnable packaging is encouraged by regulators.\nShipping containers.\nFor many years, several types of shipping containers have been returnable and reusable. These have made most sense when a reverse logistics system is available or can be readily developed. A return, reconditioning, and reuse system can save money on the cost per shipment and can reduce the environmental footprint of the packaging.\nManufacturing, particularly the automotive industry, has used heavy-duty returnable racks for shipping hoods, fenders, engines, dashboards, etc. from suppliers to final assembly plants. The racks are then returned for the next shipment cycle.\nBulk foods, chemicals, and pharmaceuticals are often shipped in reusable and returnable containers. These need to be carefully inspected, cleaned and sanitized as part of the reuse cycle. An effective quality management system is necessary.\nWooden pallets are often made to be expendable, for a single shipment. Others are heavy duty and intended for multiple shipments. Some are in \"pallet pools\" which are used, inspected, and refurbished for extended usage.\nOften reusable industrial shipping containers have bar code labels or radio-frequency identification (RFID) chips to help identify and route the containers.\nUse in the automotive industry.\nAutomotive original equipment manufacturers (OEMs) use and encourage the use of returnable packaging to move components from their vendors to their factories. The components are placed in returnable packaging and are at times and arranged in a way that facilitates movement straight to assemble lines. Such packaging replaces traditional corrugated cartons, thereby helping companies cut costs by avoiding wastage and effort required in disposing the cartons. It also helps in reducing the environmental footprint of the automotive industry.\nOther advantages of using returnable packaging include avoiding damages to parts in while in transit. Parts are at times placed in specially designed receptacles for easy picking on the assembly line contributing to fewer mistakes and simpler inventory management.\nA few examples of returnable packaging in automotive industry:\nConsumer packaging and containers.\nSeveral types of consumer containers have been in reuse systems. Reusable bottles for milk, soda, and beer have been part of closed-loop use-return-clean-refill-reuse cycles. Food storage containers are typically reusable. Thick plastic water bottles are promoted as an environmental improvement over thin single-use water bottles. Some plastic cups can be re-used, though most are disposable.\nHome canning often uses glass mason jars which are often reused several times.\nMany non-food types of containers, including reusable shopping bags, and luggage, are designed to be reused by consumers.\nWith any food packaging, proper cleaning and disinfecting between each use is critical to health.\nIn September 2019, the UK Environment, Food and Rural Affairs Committee released a report claiming that the official intervention should encourage more shops to offer refillable options instead of traditional single-use packing.\nReuse for other purposes.\nUsed packages are often reused for purposes other than their primary use. For example, a single-use plastic shopping bag might be reused as a bin bag, a household storage bag or a dog faeces bag. Steel drums can be reused as traffic barricades, dock flotation, and as musical instruments\nJustification.\nReusable packaging often costs more initially and uses more and different materials than single-use packaging. It often requires adding complexity to the distribution system. Not all packaging justifies being returnable and reusable.\nA thorough cost analysis is required. This involves all of the material, labor, transport, inspection, refurbishing, cleaning, and management costs. Often these costs may be incurred by different companies with different cost structures.\nThe environmental costs and benefits can also be complex. The material, energy, pollution, etc. needs to be accounted for throughout the entire system. A life cycle assessment offers a good methodology for this task.\nReferences.\nBooks, general references.\nIndustry Associations", "Engineering,_Manufacturing": 0.9997876287, "qwen": "Yes"}
{"id": "57699443", "revid": "359256", "url": "https://en.wikipedia.org/wiki?curid=57699443", "title": "Original Heidelberg Platen Press", "text": "The Original Heidelberg Platen Press was a letterpress printing press manufactured by the Heidelberger Druckmaschinen company in Germany. It was often referred to as the Heidelberg Windmill, after the shape and movement of its paper feed system. When introduced, it was also called the \"Super Heidelberg\" or the \"Super Speed\".\nHistory.\nThe \"Original Heidelberg Platen Press\" was introduced in 1914 and manufactured between 1923 and 1985.\nAlthough the \"Original Heidelberg Platen Press\" is no longer being manufactured, it is still in wide use for commercial and enthusiast letterpress printing.\nThe company later also produced the \"Original Heidelberg Cylinder Press\" and today produces offset presses and printing related products.\nDesign and operation.\nThe printing press is most famous for its windmill-like automatic paper feed mechanism. There are two blades that rotate from the paper feed, where it picks up a sheet of paper; to the platen, where the printing impression is made; to the delivery rack, where the paper is released; followed by the blade pointing straight up ready to start the next cycle. There are two blades mounted on opposite sides of the rotor (when one blade is picking up the next sheet, the other blade is releasing the previously printed sheet). In addition, if the press is set for precision registration (\"with gauges\"), the feed arm drops the sheet onto moving gauge blocks that then pull it into precise alignment just before the press closes, then picks it back up to carry it to the delivery rack.\nA clamshell-like mechanism performs the actual printing. In letterpress an impression is made on the paper by having a platen press the paper against a forme. The forme has the desired image in reverse: with raised parts where the ink is applied, and lowered parts where the ink is not applied. When a rotor has moved a page to the platen, the platen is pressed against the forme to make the impression (where ink is transferred from the form to the paper). The platen then opens up to release the printed page and allow the rollers to apply more ink to the forme. This cycle repeats for the next page.\nThe Original Heidelberg Platen Press also automatically inks the rollers. Ink can be added to a reservoir, or \"fountain,\" which is then spread evenly via several rollers before reaching the rollers which make contact with the forme.\nThe press is driven by an electric motor that runs a flywheel. The press also contains an air pump. Air suction is used to pick up the next sheet of paper from the feed pile, so the blade can grab it as it comes around.\nModels.\nTwo models of the press were manufactured: the Original Heidelberg 10\" x 15\" and the larger Original Heidelberg 13\" x 18\" that can print on larger sheets of paper.", "Engineering,_Manufacturing": 1.0000052452, "qwen": "Yes"}
{"id": "44424907", "revid": "1893804", "url": "https://en.wikipedia.org/wiki?curid=44424907", "title": "Process qualification", "text": "Process qualification is the qualification of manufacturing and production processes to confirm they are able to operate at a certain standard during sustained commercial manufacturing. Data covering critical process parameters must be recorded and analyzed to ensure critical quality attributes can be guaranteed throughout production. This may include testing equipment at maximum operating capacity to show quantity demands can be met. Once all processes have been qualified the manufacturer should have a complete understanding of the process design and have a framework in place to routinely monitor operations. Only after process qualification has been completed can the manufacturing process begin production for commercial use. Equally important as qualifying processes and equipment is qualifying software and personnel. A well trained staff and accurate, thorough records helps ensure ongoing protection from process faults and quick recovery from otherwise costly process malfunctions. In many countries qualification measures are also required, especially in the pharmaceutical manufacturing field.\nProcess qualification should cover the following aspects of manufacturing:\nProcess qualification is the second stage of process validation.\nA vital component of process qualification is process performance qualification protocol. PPQ protocol is essential in defining and maintaining production standards within an organization. ", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "11675811", "revid": "1008048", "url": "https://en.wikipedia.org/wiki?curid=11675811", "title": "Mount Elliott Tool and Die", "text": "Mount Elliott Tool and Die is a Stellantis North America automotive stamping plant in Detroit, Michigan that produces Stamping Dies, Checking Fixtures, Stamping Fixtures. \nIt was built in 1938 by the Briggs Manufacturing Company. Chrysler purchased the plant in 1956 and it became Outer Drive Stamping plant. The facility became a tool and die plant after Vernor Tool & Die closed in 1983 and moved their operations there. The facility was then renamed Outer Drive Manufacturing Technology Center.\nAfter the \"Pilot Operations\" and \"Advanced Stamping Manufacturing Engineering\" were moved to Chrysler Headquarters in Auburn Hills, Michigan in the 1980s, the facility was renamed \"Mt. Elliott Tool and Die\".\nMount Elliott currently employs around 300 people and is home to UAW Local 212. As of late 2018 Mount Elliot is currently idled.", "Engineering,_Manufacturing": 0.9999569654, "qwen": "Yes"}
{"id": "10872064", "revid": "3727527", "url": "https://en.wikipedia.org/wiki?curid=10872064", "title": "Hardmask", "text": "A hardmask is a material used in semiconductor processing as an etch mask instead of a polymer or other organic \"soft\" resist material.\nHardmasks are necessary when the material being etched is itself an organic polymer. Anything used to etch this material will also etch the photoresist being used to define its patterning since that is also an organic polymer. This arises, for instance, in the patterning of low-κ dielectric insulation layers used in VLSI fabrication. Polymers tend to be etched easily by oxygen, fluorine, chlorine and other reactive gases used in plasma etching. \nUse of a hardmask involves an additional deposition process, and hence additional cost. First, the hardmask material is deposited and etched into the required pattern using a standard photoresist process. Following that the underlying material can be etched through the hardmask. Finally the hardmask is removed with a further etching process.\nHardmask materials can be metal or dielectric. Silicon based masks such as silicon dioxide or silicon carbide are usually used for etching low-κ dielectrics. However, SiOCH (carbon doped hydrogenated silicon oxide), a material used to insulate copper interconnects, requires an etchant that attacks silicon compounds. For this material, metal or amorphous carbon hardmasks are used. The most common metal for hardmasks is titanium nitride, but tantalum nitride has also been used.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "10880315", "revid": "1535071", "url": "https://en.wikipedia.org/wiki?curid=10880315", "title": "Reaction injection molding", "text": "Reaction injection molding (RIM) is similar to injection molding except thermosetting polymers are used, which requires a curing reaction to occur within the mold.\nCommon items made via RIM include automotive bumpers, air spoilers, and fenders.\nProcess.\nThe two parts of the polymer are mixed together, usually by injecting them under high pressure into an impinging mixer. Then the mixture is injected under lower pressure into a mold. The mixture is allowed to sit in the mold long enough for it to expand and cure.\nIf reinforcing agents are added to the mixture then the process is known as reinforced reaction injection molding (RRIM). Common reinforcing agents include glass fibers and mica. This process is usually used to produce rigid foam automotive panels.\nA subset of RIM is structural reaction injection molding (SRIM), which uses fiber meshes for the reinforcing agent. The fiber mesh is first arranged in the mold and then the polymer mixture is injection molded over it.\nThe most common RIM processable material is polyurethane (known generally as PU-RIM), but others include polyureas, polyisocyanurates, polyesters, polyphenols, polyepoxides, and nylon 6. For polyurethane one component of the mixture is polyisocyanate and the other component is a blend of polyol, surfactant, catalyst, and blowing agent.\nAdvantages and disadvantages.\nReaction injection molding can produce strong, flexible, lightweight parts which can easily be painted. It also has the advantage of quick cycle times compared to typical vacuum cast materials. The bi-component mixture injected into the mold has a much lower viscosity than molten thermoplastic polymers, therefore large, light-weight, and thin-walled items can be successfully RIM processed. This thinner mixture also requires less clamping forces, which leads to smaller equipment and ultimately lower capital expenditures. Another advantage of RIM processed foam is that a high-density skin is formed with a low-density core.\nThe disadvantages are slow cycle times, compared to injection molding, and expensive raw materials.\nTooling.\nMachined steel or aluminum; cast aluminum; silicone rubber; epoxy resin; nickel. The machines can be large or small depending on the size of part required.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "10897444", "revid": "37167220", "url": "https://en.wikipedia.org/wiki?curid=10897444", "title": "Riveting machine", "text": "A riveting machine is used to automatically set (squeeze) rivets in order to join materials together. The riveting machine offers greater consistency, productivity, and lower cost when compared to manual riveting.\nTypes.\nAutomatic feed riveting machines include a hopper and feed track which automatically delivers and presents the rivet to the setting tools which overcomes the need for the operator to position the rivet. The downward force required to deform the rivet with an automatic riveting machine is created by a motor and flywheel combination, pneumatic cylinder, or hydraulic cylinder. Manual feed riveting machines usually have a mechanical lever to deliver the setting force from a foot pedal or hand lever.\nRiveting machines can be sub-divided into two broad groups — impact riveting machines and orbital (or radial) riveting machines.\nImpact riveting.\nImpact riveting machines set the rivet by driving the rivet downwards, through the materials to be joined and on into a forming tool (known as a rollset). This action causes the end of the rivet to roll over in the rollset which causes the end of the rivet to flare out and thus join the materials together. Impact riveting machines are very fast and a cycle time of 0.5 seconds is typical.\nOrbital riveting.\nOrbital riveting machines have a spinning forming tool (known as a peen) which is gradually lowered into the rivet which spreads the material of the rivet into a desired shape depending upon the design of the tool. Orbital forming machines offer the user more control over the riveting cycle but the trade off is in cycle time which can be 2 or 3 seconds.\nThere are different types of riveting machines. Each type of machine has unique features and benefits. The orbital riveting process is different from impact riveting and spiralform riveting. Orbital riveting requires less downward force than impact or spiral riveting. Also, orbital riveting tooling typically lasts longer.\nOrbital riveting machines are used in a wide range of applications including brake linings for commercial vehicles, aircraft, and locomotives, textile and leather goods, metal brackets, window and door furniture, latches and even mobile phones. Many materials can be riveted together using orbital riveting machines including delicate and brittle materials, and sensitive electrical or electronic components.\nThe orbital riveting process uses a forming tool mounted at a 3 or 6° angle. The forming tool contacts the material and then presses it while rotating until the final form is achieved. The final form often has height and/or diameter specifications.\nPneumatic orbital riveting machines typically provide downward force in the range. Hydraulic orbital riveting machines typically provide downward force in the range.\nRadial (Spiralform) riveting.\nRadial riveting is subtly different from orbital forming. In most cases however, where high-quality joints are demanded, the radial riveting technology is the appropriate procedure due to the low cyle time, the little force needed and the high quality results obtained.\nThe riveting peen describes a rose-petal path. The rivet is deformed in three directions. Radially outwards, radially inwards and overlying also tangentially.\nExcellent surface structure of the closing head: With the Radial riveting process, the tool itself does not rotate. The friction between tool and work-piece is thus at a minimum. The result is an excellent surface structure.\nLow workpiece loading: Even bakelite or ceramic parts can be riveted. Lateral forces are negligible. Clamping is usually unnecessary.\nRollerform riveting.\nRollerforming is a subset of orbital forming. Rollerforming uses the same powerhead as orbital forming but instead of a peen has multiple wheels that circle the workpiece and combine two similar or non-similar materials together with a seamless and smooth gentle bonding via downward pressure as the rollers move downward or inward on the piece.\nAutomatic drilling and riveting machine.\nThese machines take the automation one step farther by clamping the material and drilling or countersinking the hole in addition to riveting. They are commonly used in the aerospace industry because of the large number of holes and rivets required to assemble the aircraft skin.\nApplications.\nRiveting machines are used in a wide range of applications including brake linings for commercial vehicles, aircraft, and locomotives, textile and leather goods, metal brackets, window and door furniture, latches and even mobile phones. Many materials can be riveted together using riveting machines including delicate and brittle materials, and sensitive electrical or electronic components.", "Engineering,_Manufacturing": 0.9999051094, "qwen": "Yes"}
{"id": "10902811", "revid": "6046731", "url": "https://en.wikipedia.org/wiki?curid=10902811", "title": "Threaded insert", "text": "A threaded insert, also known as a threaded bushing, is a fastener element that is inserted into an object to add a threaded hole. They may be used to repair a stripped threaded hole, provide a durable threaded hole in a soft material, place a thread on a material too thin to accept it, mold or cast threads into a work piece thereby eliminating a machining operation, or simplify changeover from unified to metric threads or vice versa.\nTypes.\nThread inserts come in many varieties, depending on the application. Threaded inserts for plastics are used in plastic materials and applied with thermal insertion or ultrasonic welding machines.\nManufacturers of ready-to-assemble furniture often ship the parts with threaded inserts and other kinds of knock-down fasteners pre-installed.\nPeople who use sheet metal or sandwich panel or honeycomb sandwich-structured composite often install threaded inserts to spread shear, tension, and torque loads over a larger area of the material.\nCaptive nut.\nCaptive nuts come in two basic styles. One type, the cage nut or clip-on nut is a conventional nut held captive by a sheet metal carrier that clips onto the part to be connected. These are generally used to attach screws to sheet metal parts too thin to be threaded, and\nthey can generally be attached, removed and reused with simple hand tools.\nThe second type of captive nut is a threaded insert. These are either pressed into holes in the material to be joined or moulded in. In either case, part of the insert is generally knurled to get a good grip on the material supporting the insert. One variant, the swage nut, has a knurled portion that swages the sides of a soft metal hole to more tightly grip the nut. Press fit and swaged captive nuts are used in panels that are too thin to be threaded or in soft materials that are too weak to be threaded. They are installed by pressing them in with an arbor press.\nThreaded inserts are commonly used in plastic casings, housing, and parts to create a metal thread (typically: brass or stainless steel) to allow for screws to be used in the assembly of many consumer electronics and consumer products. These may be cast in place in injection molded parts or they may be added by thermal insertion. In the latter, the insert is heated and then pressed into a hollow in the plastic part. The heat causes local melting in the plastic. Ultrasonic Insertion is the process used to apply vibration and pressure to install the threaded insert into a molded hollow boss (hole) of a plastic part. The ultrasonic vibrations melt the thermoplastic material where the metal insert is in contact, and pressure is applied to press it into position. The material typically reforms around the knurled body of the threaded insert to ensure a good retention.\nExternally-threaded inserts.\nExternally threaded inserts have threads on the outside and inside of the insert. The insert is threaded into a pre-tapped hole, or some inserts tap their own threads in a drilled or molded hole. It is then anchored by various means, such as a nylon locking element. Inserts that are anchored via Loctite are more commonly known by the trademarked name \"E-Z Lok\". A thin walled solid bushing insert by the trademarked name \"TIME-SERT\" is locked in by rolling the bottom few internal thread into the base material with a special install driver which will permanently lock the insert in place. Key locking inserts, more commonly known by the trademarked name \"Keenserts\", use keys that are hammered into grooves through the threads, permanently locking the insert. Inserts that are self-tapping and lock via friction are more commonly known by the trademarked names Tap-lok or Speedserts.\nHelical insert.\nA helical insert (also called a screw thread insert (STI), although most users call them all by the prominent brand name, Heli-Coil® or Recoil®) is an insert made of diamond shaped stainless steel, or phosphor bronze, coiled wire. The\ncoil of wire screws into a threaded hole, where it forms a smaller diameter internal thread for a screw or stud. These inserts provide a convenient means of repairing stripped-out threads. These inserts are commonly sold as kits with matched tap, coil, and insert tool. \nIn soft materials, they are used to provide stronger threads than can be obtained by direct tapping of the base materials, e.g. aluminium, zinc die castings, wood, magnesium, plastic.\nAn example application is engine repair after unintentionally destroying the threads in the socket for a spark plug by over-torquing or by cross-threading.\nMold-in inserts.\nMold-in inserts are internally threaded and have a specially shaped outer diameter to anchor the insert in plastic. The insert is placed in the mold of an injection molded part beforehand. The mold is then closed and filled with the plastic filling in around the insert. These inserts can also be heated and pressed into pre-made thermoplastics.\nFor softer more pliable plastics, hexagonal or square inserts with deep and wide grooves allow the plastic to flow and adhere. The process allows large product manufacture i.e. fuel tanks, boats etc., so the torque inserts may be of large thread sizes.\nPress fit inserts.\nPress fit inserts are internally threaded and have a knurled outer diameter. They are pressed into a plain hole with an arbor press.\nPotted inserts.\nAn insert that is potted-in refers to the application of epoxy to fix it to a panel, such as a honeycomb sandwich panel, which are often used in commercial aircraft.\nStrength factor for threaded inserts.\n\"Resistance\" is the key strength factor in case of inserts, pull-out & torque-out are the two parameters to judge inserts.\nKnurling.\nKnurling is the metalworking which is done on the outer side of the component. In case of Brass Insert, knurling plays an important role in increasing pull-out & torque-out resistance. Types of knurling and its benefit are as follows:\nInstallation methods.\nFor industrial purposes, following installation methods are the standards:", "Engineering,_Manufacturing": 1.0000038147, "qwen": "Yes"}
{"id": "51457325", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=51457325", "title": "Machine tending", "text": "Machine tending refers to the automated operation of industrial machine tools in a manufacturing plant, primarily using robot automation systems. While loading and unloading is the primary function of machine tending systems, often the robot performs other valuable functions within the automation system such as part inspection, blow off, wash, deburring, sorting, packaging and gauging.\nBenefits of machine tending systems include:\nBecause of the sophistication, functionality, and costs associated with machine tending systems, most manufacturers require a capital approval process prior to investing in these systems where executive management must approve the purchase. Typically, an ROI (return on investment) is calculated to justify the purchase.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "4999945", "revid": "43770829", "url": "https://en.wikipedia.org/wiki?curid=4999945", "title": "Automated storage and retrieval system", "text": "An automated storage and retrieval system (ASRS or AS/RS) consists of a variety of computer-controlled systems for automatically placing and retrieving loads from defined storage locations. Automated storage and retrieval systems (AS/RS) are typically used in applications where: \nAn AS/RS can be used with standard loads as well as nonstandard loads, meaning that each standard load can fit in a uniformly-sized volume; for example, the film canisters in the image of the Defense Visual Information Center are each stored as part of the contents of the uniformly sized metal boxes, which are shown in the image. Standard loads simplify the handling of a request of an item. In addition, audits of the accuracy of the inventory of contents can be restricted to the contents of an individual metal box, rather than undergoing a top-to-bottom search of the entire facility, for a single item. \nThey can also be used in self storage places.\nOverview.\nAS/RS systems are designed for automated storage and retrieval of parts and items in manufacturing, distribution, retail, wholesale and institutions. They first originated in the 1960s, initially focusing on heavy pallet loads but with the evolution of the technology the handled loads have become smaller. The systems operate under computerized control, maintaining an inventory of stored items. Retrieval of items is accomplished by specifying the item type and quantity to be retrieved. The computer determines where in the storage area the item can be retrieved from and schedules the retrieval. It directs the proper automated storage and retrieval machine (SRM) to the location where the item is stored and directs the machine to deposit the item at a location where it is to be picked up. A system of conveyors and or automated guided vehicles is sometimes part of the AS/RS system. These take loads into and out of the storage area and move them to the manufacturing floor or loading docks. To store items, the pallet or tray is placed at an input station for the system, the information for inventory is entered into a computer terminal and the AS/RS system moves the load to the storage area, determines a suitable location for the item, and stores the load. As items are stored into or retrieved from the racks, the computer updates its inventory accordingly.\nThe benefits of an AS/RS system include reduced labor for transporting items into and out of inventory, reduced\ninventory levels, more accurate tracking of inventory, and space savings. Items are often stored more densely than in systems where items are stored and retrieved manually.\nWithin the storage, items can be placed on trays or hang from bars, which are attached to chains/drives in order to move up and down. The equipment required for an AS/RS include a storage & retrieval machine (SRM) that is used for rapid storage and retrieval of material. SRMs are used to move loads vertically or horizontally, and can also move laterally to place objects in the correct storage location.\nThe trend towards Just In Time production often requires sub-pallet level availability of production inputs, and AS/RS is a much faster way of organizing the storage of smaller items next to production lines.\nThe Material Handling Institute of America (MHIA), the non-profit trade association for the material handling world, and its members have categorised AS/RS into two primary segments: Fixed Aisle and Carousels/Vertical Lift Modules (VLMs). Both sets of technologies provide automated storage and retrieval for parts and items, but use different technologies. Each technology has its unique set of benefits and disadvantages. Fixed Aisle systems are characteristically larger systems whereas carousels and Vertical Lift Modules are used individually or grouped, but in small to medium-sized applications.\nA fixed-aisle AS/R machine (stacker crane) is one of two main designs: single-masted or double masted. Most are supported on a track and ceiling guided at the top by guide rails or channels to ensure accurate vertical alignment, although some are suspended from the ceiling. The 'shuttles' that make up the system travel between fixed storage shelves to deposit or retrieve a requested load (ranging from a single book in a library system to a several ton pallet of goods in a warehouse system). The entire unit moves horizontally within an aisle, while the shuttles are able to elevate up to the necessary height to reach the load, and can extend and retract to store or retrieve loads that are several positions deep in the shelving. A semi-automated system can be achieved by utilizing only specialized shuttles within an existing rack system.\nAnother AS/RS technology is known as shuttle technology. In this technology the horizontal movement is made by independent shuttles each operating on one level of the rack while a lift at a fixed position within the rack is responsible for the vertical movement. By using two separate machines for these two axes the shuttle technology is able to provide higher throughput rates than stacker cranes.\nStorage and Retrieval Machines pick up or drop off loads to the rest of the supporting transportation system at specific stations, where inbound and outbound loads are precisely positioned for proper handling.\nIn addition, there are several types of Automated Storage & Retrieval Systems (AS/RS) devices called Unit-load AS/RS, Mini-load AS/RS, Mid-Load AS/RS, Vertical Lift Modules (VLMs), Horizontal Carousels and Vertical Carousels. These systems are used either as stand-alone units or in integrated workstations called pods or systems. These units are usually integrated with various types of pick to light systems and use either a microprocessor controller for basic usage or inventory management software. These systems are ideal for increasing space utilization up to 90%, productivity levels by 90%, accuracy to 99.9%+ levels and throughput up to 750 lines per hour/per operator or more depending on the configuration of the system.\nAdvantages.\nAn effective automated storage and retrieval system provides several benefits for supply chain management\nVertical lift module.\nVertical lift modules (VLMs) can be built to a height to match the available overhead space in a facility. Multiple units can be placed in 'pods' whereby an operator can retrieve items from one unit while the other units are moving. Variants include width, height, load, speed and a control system.\nThe VLM is a board controlled automated vertical lift module. Inventory within the VLM is stored on front and rear tray locations or rails. When a tray is requested, either by entering a tray number in the built-in control pad or by requesting a part through software, an extractor travels vertically between the two columns of trays and pulls the requested tray from its location and brings it to an access point. The operator then picks or replenishes stock and the tray is returned to its home upon confirmation.\nVLM systems are sold in numerous configurations, which could be applied in different industries, logistics, as well as office settings. The VLM systems could be customized to fully utilize the height of the facility, even through multiple floors. With the capability of multiple access openings on different floors, a VLM system is able to provide an innovative storage and retrieval solution. The rapid movement of the extractor, as well as inventory management software, can dramatically increase the efficiency of the picking process. This occurs by simultaneously retrieving and storing trays in multiple units. Unlike large AS/RS systems, which require a complete overhaul of the warehouse or production line, the vertical lift modules are modularized, which can be easily integrated into the existing system, or to be rolled out in gradually over different phases.\nMost common applications include: MRO, order picking, consolidation, kitting, parts handling, buffering, inventory storage, WIP, buffer storage, and many more.\nVLMs provide floor space savings, increased labor productivity and picking accuracy, improved worker ergonomics, and controlled process.\nMost VLMs offer dynamic space storage which measures the tray every time it is returned to the unit to optimize space, safety features and some offer tilt-tray delivery for increased ergonomic accessibility, and laser pointers which indicate the exact item to be picked on each tray.\nHorizontal carousels.\nA horizontal carousel is a series of bins which revolve on an oval track. Every bin has shelves which are adjustable to and can be configured for a myriad of standard and special applications. An operator simply inputs a bin number, part number or cell location and the carousel will rotate via the shortest path. Multiple horizontal carousels integrated with pick to light technology and inventory management software (a pod of carousels) are used for order fulfillment.\nA wave of orders is sent to the pod. A group of orders is selected to create a batch. The operator simply follows the lights and pick round-robin from the carousels and place items in a batch station behind them. Each carousel pre-positions and rotates when picked. By applying the \"product to person\" principle, operators do not have to move from their position to prepare the order.\nWhen the batch is complete, a new batch is inducted and the process repeated until the wave is complete. Horizontal carousels can save up to 75% of floorspace, increase productivity by 2/3, accuracy levels to 99.9+% levels and throughput up to 750 lines per hour/operator.\nHorizontal carousel systems generally outperform robotic systems for a fraction of the cost. Horizontal carousels are the most cost-effective AS/RS system available.\nRobotic Inserter/Extractor devices can also be used for horizontal carousels. The robotic device is positioned in the front or rear of up to three horizontal carousels tiered high. The robot grabs the tote required in the order and often replenishes at the same time to speed up throughput. The tote(s) are then delivered to a conveyor, which routes it to a work station for picking or replenishing. Up to eight transactions per minute per unit can be done. Totes or containers up to 36\" x 36\" x 36\" can be used in a system.\nOn a simplistic level, horizontal carousels are also often used as \"rotating shelving.\" With simple \"fetch\" command, items are brought to the operator and otherwise wasted space is eliminated.\nAS/RS Applications: Most applications of AS/RS technology have been associated with warehousing and distribution operations. An AS/RS can also be used to store raw materials and work in process in manufacturing. Three application areas can be distinguished for AS/RS: (1) Unit load storage and handling, (2) Order picking, and (3) Work in process storage. Unit load storage and retrieval applications are represented by unit load AS/RS and deep-lane storage systems. These kinds of applications are commonly found in warehousing for finishing goods in a distribution center, rarely in manufacturing. Deep-lane systems are used in the food industry. As described above, order picking involves retrieving materials in less than full unit load quantities. Minilpass, man-on board, and items retrieval systems are used for this second application area.\nWork in process storage is a more recent application of automated storage technology. While it is desirable to minimize the amount of work in process, WIP is unavoidable and must be effectively managed. Automated storage systems, either automated storage/retrieval systems or carousel systems, represent an efficient way to store materials between processing steps, particularly in batch and job shop production. In high production, work in process is often carried between operations by conveyor system, which this serve both storage and transport functions.\nInstalled applications.\nInstalled applications of this technology can be wide-ranging. In some libraries, such as at University of Nevada, Reno library, such a system is employed to retrieve books. Still others in use involve retrieval of bicycles from a bicycle tree, as in the case of systems in Japan.\nInstitutions using automated storage and retrieval systems.\nSome examples of academic institutions using automated storage and retrieval systems are;\nMan-aboard systems.\nA man-aboard system can provide significant floorspace savings over manual or forklift operations but is not truly an AS/RS, as the operation is still manual. Storage system heights are not limited by the reach height of the order picker, as the picker rides along on the platform as it is moved vertically or horizontally to the various storage locations. Shelves or storage cabinets can be stacked as high as floor loading, weight capacity, throughput requirements, and/or ceiling heights will permit. Man-aboard storage and retrieval systems are far and away the most expensive picker-to-stock equipment alternative but are less expensive than a fully automated system. Aisle-captive storage/retrieval machines reaching heights up to cost around $125,000. Hence, there must be enough storage density and/or productivity improvement over cart and tote picking to justify the investment. Also, because vertical travel is slow compared to horizontal travel, typical picking rates in man-aboard operations range between 40 and 250 lines per person-hour. The range is large because there is a wide variety of operating schemes for man-aboard systems. Man-aboard systems are typically appropriate for slow-moving items where space is fairly expensive.", "Engineering,_Manufacturing": 0.9999947548, "qwen": "Yes"}
{"id": "21114537", "revid": "1127293777", "url": "https://en.wikipedia.org/wiki?curid=21114537", "title": "Electrochemical grinding", "text": "Electrochemical grinding is a process that removes electrically conductive material by grinding with a negatively charged abrasive grinding wheel, an electrolyte fluid, and a positively charged workpiece. Materials removed from the workpiece stay in the electrolyte fluid. Electrochemical grinding is similar to electrochemical machining but uses a wheel instead of a tool shaped like the contour of the workpiece.\nProcess.\nThe electrochemical grinding process combines traditional electrochemical machining and grinding processes to remove material from a workpiece. A grinding wheel is used as a cutting tool as a cathode and the workpiece is an anode. During the process, electrolytic fluid, typically sodium nitrate, is pumped into the space between the workpiece and the grinding wheel. Other electrolytes used include sodium hydroxide, sodium carbonate, and sodium chloride. This electrolytic fluid will cause electrochemical reactions to occur at the workpiece surface which oxidize the surface, thereby removing material. As a consequence of the oxidation which occurs, layers of oxide films will form on the workpiece surface, and these need to be removed by the grinding wheel. A couple schematics of the process are provided below.\nAbrasive materials, either diamond or aluminum oxide, are bonded to the grinding wheel, which allows the wheel to remove the oxide layers on the workpiece surface by abrasive action. Appropriate materials used for electrolyte fluid and the grinding wheel abrasives are summarized in the table below.\nMost material removal is by the electrochemical reactions which occur at the workpiece surface. Five percent or less of the material removal is carried out by the abrasive action of the grinding wheel. The fact that most material is not removed by abrasive action helps increase the life of the grinding wheel; that is, the tool will take a long time to wear down. The electrolytic fluid serves another useful purpose - it flushes out leftover material in between the grinding wheel and workpiece. The abrasive particles bonded to the grinding wheel will help to electrically insulate the space between the grinding wheel and workpiece. An equation giving the material removal rate for an electrochemical grinding process is provided in and is stated here as:\nMRR = GI/ρF\nwhere ρ is the workpiece density, G is the total mass of the workpiece, I is the current supplied, MRR is the material removal rate, and F is Faraday's constant.\nSome of the main factors which govern the performance of an electrochemical grinding process include current supplied, rotation speed of the grinding wheel, the workpiece feed rate, the type of electrolyte used, electrolyte feed rate, and the workpiece's chemical properties. By changing these parameters, one can alter the material removal rate. Increasing the supplied current, rotation speed of the wheel, electrolyte feed rate, or the workpiece feed rate will lead to an increase in material removal rate (MRR), while decreasing these properties will do the opposite. If the workpiece is more reactive to the electrolyte used, then the material removal rate will increase. The grinding wheel is usually rotated with a surface speed of 1200–2000 m/min and supplied currents are around 1000A.\nThe accuracy of parts made by electrochemical grinding is strongly dictated by the chemical properties of the workpiece and electrolytic fluid used. If the workpiece is very reactive to the electrolyte, and if too much electrolyte is pumped into the space between the grinding wheel and workpiece, it may be difficult to control the material removal, which can lead to loss of accuracy. Also, accuracy may be reduced if the workpiece feed rate is too high.\nThe wheels are metal disks with abrasive particles embedded. Copper, brass, and nickel are the most commonly used materials; aluminum oxide is typically used as an abrasive when grinding steel. A thin layer of diamond particles will be used when grinding carbides or steels harder than 65 Rc.\nAn electrolytic spindle with carbon brushes, acting as a commutator, holds the wheel. The spindle receives a negative charge from the DC power supply, which gives the workpiece a positive charge. The electrolytic fluid is applied where the work contacts the tool by a nozzle similar to that which supplies coolant in conventional grinding. The fluid works with the wheel to form electrochemical cells that oxidize the surface of the workpiece. As the wheel carries away the oxide, fresh metal is exposed. Removing the oxidized fluid may only require a pressure of 20 psi or less, causing much less distortion than mechanical grinding. The wheel is subject to little wear, reducing the need for truing and dressing.\nApplications.\nElectrochemical grinding is often used for hard materials where conventional machining is difficult and time-consuming, such as stainless steel and some exotic metals. For materials with hardness greater than 65 HRC, ECG can have a material removal rate 10 times that of conventional machining. Because ECG involves little abrasion, it is often used for processes where the surface of the part is needs to be free of burrs, scratches, and residual stresses. Because of these properties, electrochemical grinding has a number of useful applications.\nAdvantages and disadvantages.\nOne of the key advantages of electrochemical grinding is the minimal wear that the grinding wheel tool experiences. This is because the majority of the material is removed by the electrochemical reaction that occurs between the cathode and anode. The only time that abrasive grinding actually occurs is in removing the film that develops on the surface of the workpiece. Another advantage of electrochemical grinding is that it can be used to machine hard materials. Hard materials pose a difficulty to other types of machining due to the tool wear that is associated with machining hard materials. It may come as a bit of a surprise that electrochemical grinding can remove material from a hard surface and experience minimal wear. Because most material is removed through electrochemical reactions, the workpiece does not experience heat damage like it would in a conventional grinding process.\nElectrochemical grinding also has a few disadvantages as well. The system consists of the anode workpiece and the cathode grinding wheel. In order to create those conditions both the workpiece and the grinding wheel must be conductive. This limits the types of workpiece materials that are suitable for electrochemical grinding. Another disadvantage of electrochemical grinding is that it is only applicable to surface grinding. It is not possible to apply electrochemical grinding to workpieces that have cavities, due to the grinding wheels inability to remove the film deposit with in the cavity. One other disadvantage is the electrolytic fluid can cause corrosion at the workpiece and grinding wheel surfaces. Lastly, electrochemical grinding is more complicated than traditional machining methods. This will require more experienced personnel to operate the machinery, which will lead to higher production cost. Another disadvantage is that chemical used during grinding process need to be properly disposed of depending on the environmental regulation.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "21117179", "revid": "25977910", "url": "https://en.wikipedia.org/wiki?curid=21117179", "title": "Weld line", "text": "In manufacturing, the Weld line or Knit line or Meld line is the line where two flow fronts meet when there is the inability of two or more flow fronts to \"knit\" together, or \"weld\", during the molding process. These lines usually occur around holes or obstructions and cause locally weak areas in the molded part. Knit lines are considered molding defects, and occur when the mold or/and material temperatures are set too low: thus the materials will be cold when they meet, so that they do not bond perfectly. This can cause a weak area in the part which can cause breakage when the part is under stress. Weld lines therefore occur during machine start-up, when equilibrium conditions have not been met. Mouldings made in this setting-up period must be rejected. \nThere are many Computer Aided Engineering tools that are available that can predict where these areas could occur, but a skilled designer will be able to predict where such defects can be found by examining the tool or product.\nWeld lines are not found in other manufacturing methods such as Rotational moulding, but can exist in extrusion, especially where there are internal metal supports for a die. The defects are then known as spider lines.\nCauses.\nWeld lines can be caused by several different problems:", "Engineering,_Manufacturing": 0.9976323247, "qwen": "Yes"}
{"id": "152654", "revid": "1169982955", "url": "https://en.wikipedia.org/wiki?curid=152654", "title": "Electrical connector", "text": "Components of an electrical circuit are electrically connected if an electric current can run between them through an electrical conductor. An electrical connector is an electromechanical device used to create an electrical connection between parts of an electrical circuit, or between different electrical circuits, thereby joining them into a larger circuit. Most electrical connectors have a genderi.e. the male component, called a \"plug\", connects to the female component, or \"socket\". The connection may be removable (as for portable equipment), require a tool for assembly and removal, or serve as a permanent electrical joint between two points. An adapter can be used to join dissimilar connectors.\nThousands of configurations of connectors are manufactured for power, data, and audiovisual applications. Electrical connectors can be divided into four basic categories, differentiated by their function:\nIn computing, electrical connectors are considered a physical interface and constitute part of the physical layer in the OSI model of networking.\nPhysical construction.\nIn addition to the classes mentioned above, connectors are characterised by their pinout, method of connection, materials, size, contact resistance, insulation, mechanical durability, ingress protection, lifetime (number of cycles), and ease of use.\nIt is usually desirable for a connector to be easy to identify visually, rapid to assemble, inexpensive, and require only simple tooling. In some cases an equipment manufacturer might choose a connector specifically because it is \"not\" compatible with those from other sources, allowing control of what may be connected. No single connector has all the ideal properties for every application; the proliferation of types is a result of the diverse yet specific requirements of manufacturers.\nMaterials.\nElectrical connectors essentially consist of two classes of materials: conductors and insulators. Properties important to conductor materials are contact resistance, conductivity, mechanical strength, formability, and resilience. Insulators must have a high electrical resistance, withstand high temperatures, and be easy to manufacture for a precise fit\nElectrodes in connectors are usually made of copper alloys, due to their good conductivity and malleability. Alternatives include brass, phosphor bronze, and beryllium copper. The base electrode metal is often coated with another inert metal such as gold, nickel, or tin. The use of a coating material with good conductivity, mechanical robustness and corrosion resistance helps to reduce the influence of passivating oxide layers and surface adsorbates, which limit metal-to-metal contact patches and contribute to contact resistance. For example, copper alloys have favorable mechanical properties for electrodes, but are hard to solder and prone to corrosion. Thus, copper pins are usually coated with gold to alleviate these pitfalls, especially for analog signals and high-reliability applications.\nContact \"carriers\" that hold the parts of a connector together are usually made of plastic, due to its insulating properties. \"Housings\" or \"backshells\" can be made of molded plastic and metal. Connector bodies for high-temperature use, such as thermocouples or associated with large incandescent lamps, may be made of fired ceramic material.\nFailure modes.\nThe majority of connector failures result in intermittent connections or open contacts:\nConnectors are purely passive componentsthat is, they do not enhance the function of a circuitso connectors should affect the function of a circuit as little as possible. Insecure mounting of connectors (primarily chassis-mounted) can contribute significantly to the risk of failure, especially when subjected to extreme shock or vibration. Other causes of failure are connectors inadequately rated for the applied current and voltage, connectors with inadequate ingress protection, and threaded backshells that are worn or damaged.\nHigh temperatures can also cause failure in connectors, resulting in an \"avalanche\" of failuresambient temperature increases, leading to a decrease in insulation resistance and increase in conductor resistance; this increase generates more heat, and the cycle repeats.\nFretting (so-called \"dynamic corrosion\") is a common failure mode in electrical connectors that have not been specifically designed to prevent it, especially in those that are frequently mated and de-mated. Surface corrosion is a risk for many metal parts in connectors, and can cause contacts to form a thin surface layer that increases resistance, thus contributing to heat buildup and intermittent connections. However, remating or reseating a connector can alleviate the issue of surface corrosion, since each cycle scrapes a microscopic layer off the surface of the contact(s), exposing a fresh, unoxidised surface.\nCircular connectors.\nMany connectors used for industrial and high-reliability applications are circular in cross section, with a cylindrical housing and circular contact interface geometries. This is in contrast to the rectangular design of some connectors, e.g. USB or blade connectors. They are commonly used for easier engagement and disengagement, tight environmental sealing, and rugged mechanical performance. They are widely used in military, aerospace, industrial machinery, and rail, where MIL-DTL-5015 and MIL-DTL-38999 are commonly specified. Fields such as sound engineering and radio communication also use circular connectors, such as XLR and BNC. AC power plugs are also commonly circular, for example, Schuko plugs and IEC 60309.\nThe M12 connector, specified in IEC 61076-2-101, is a circular electrical plug/receptacle pair with 12mm OD mating threads, used in NMEA 2000, DeviceNet, IO-Link, some kinds of Industrial Ethernet, etc.\nA disadvantage of the circular design is its inefficient use of panel space when used in arrays, when compared to rectangular connectors.\nCircular connectors commonly use backshells, which provide physical and electromagnetic protection, whilst sometimes also providing a method for locking the connector into a receptacle. In some cases, this backshell provides a hermetic seal, or some degree of ingress protection, through the use of grommets, O-rings, or potting.\nHybrid connectors.\nHybrid connectors allow the intermixing of many connector types, usually by way of a housing with inserts. These housings may also allow intermixing of electrical and non-electrical interfaces, examples of the latter being pneumatic line connectors, and optical fiber connectors. Because hybrid connectors are modular in nature, they tend to simplify assembly, repair, and future modifications. They also allow the creation of composite cable assemblies that can reduce equipment installation time by reducing the number of individual cable and connector assemblies.\nMechanical features.\nPin sequence.\nSome connectors are designed such that certain pins make contact before others when inserted, and break first on disconnection. This is often used in power connectors to protect equipment, e.g. connecting safety ground first. It is also employed for digital signals, as a method to sequence connections properly in hot swapping.\nKeying.\nMany connectors are keyed with some mechanical component (sometimes called a \"keyway\"), which prevents mating in an incorrect orientation. This can be used to prevent mechanical damage to connectors, from being jammed in at the wrong angle or into the wrong connector, or to prevent incompatible or dangerous electrical connections, such as plugging an audio cable into a power outlet. Keying also prevents otherwise symmetrical connectors from being connected in the wrong orientation or \"polarity\". Keying is particularly important for situations where there are many similar connectors, such as in signal electronics. For instance, XLR connectors have a notch to ensure proper orientation, while Mini-DIN plugs have a plastic projection that fits into a corresponding hole in the socket (they also have a notched metal skirt to provide secondary keying).\nLocking mechanisms.\nSome connector housings are designed with locking mechanisms to prevent inadvertent disconnection or poor environmental sealing. Locking mechanism designs include locking levers of various sorts, jackscrews, screw-in shells, push-pull connector, and toggle or bayonet systems. Some connectors, particularly those with large numbers of contacts, require high forces to connect and disconnect. Locking levers and jackscrews and screw-in shells for such connectors frequently serve both to retain the connector when connected and to provide the force needed for connection and disconnection. Depending on application requirements, housings with locking mechanisms may be tested under various environmental simulations that include physical shock and vibration, water spray, dust, etc. to ensure the integrity of the electrical connection and housing seals.\nBackshells.\nBackshells are a common accessory for industrial and high-reliability connectors, especially circular connectors. Backshells typically protect the connector and/or cable from environmental or mechanical stress, or shield it from electromagnetic interference. Many types of backshells are available for different purposes, including various sizes, shapes, materials, and levels of protection. Backshells usually lock onto the cable with a clamp or moulded boot, and may be threaded for attachment to a mating receptacle. Backshells for military and aerospace use are regulated by SAE AS85049 within the USA.\nHyperboloid contacts.\nTo deliver ensured signal stability in extreme environments, traditional pin and socket design may become inadequate. Hyperboloid contacts are designed to withstand more extreme physical demands, such as vibration and shock. They also require around 40% less insertion force as low as per contact,which extends the lifespan, and in some cases offers an alternative to zero insertion force connectors.\nIn a connector with hyperboloid contacts, each female contact has several equally spaced longitudinal wires twisted into a hyperbolic shape. These wires are highly resilient to strain, but still somewhat elastic, hence they essentially function as linear springs. As the male pin is inserted, axial wires in the socket half are deflected, wrapping themselves around the pin to provide a number of contact points. The internal wires that form the hyperboloid structure are usually anchored at each end by bending the tip into a groove or notch in the housing.\nWhilst hyperboloid contacts may be the only option to make a reliable connection in some circumstances, they have the disadvantage of taking up greater volume in a connector, which can cause problems for high-density connectors. They are also significantly more expensive than traditional pin and socket contacts, which has limited their uptake since their invention in the 1920s by Wilhelm Harold Frederick. In the 1950s, Francois Bonhomme popularised hyperboloid contacts with his \"Hypertac\" connector, which was later acquired by Smiths Group. During the following decades, the connectors steadily gained popularity, and are still used for medical, industrial, military, aerospace, and rail applications (particularly trains in Europe).\nPogo pins.\n\"Pogo pin\" or \"spring loaded\" connectors are commonly used in consumer and industrial products, where mechanical resilience and ease of use are priorities. The connector consists of a barrel, a spring, and a plunger. They are in applications such as the MagSafe connector where a quick disconnect is desired for safety. Because they rely on spring pressure, not friction, they can be more durable and less damaging than traditional pin and socket design, leading to their use in in-circuit testing.\nCrown spring connectors.\nCrown spring connectors are commonly used for higher current flows and industrial applications. They have a high number of contact points, which provides a more electrically reliable connection than traditional pin and socket connectors.\nMethods of connection.\nWhilst technically inaccurate, electrical connectors can be viewed as a type of adapter to convert between two connection methods, which are permanently connected at one end and (usually) detachable at the other end. By definition, each end of this \"adapter\" has a different connection methode.g. the solder tabs on a male phone connector, and the male phone connector itself. In this example, the solder tabs connected to the cable represent the permanent connection, whilst the male connector portion interfaces with a female socket forming a detachable connection.\nThere are many ways of applying a connector to a cable or device. Some of these methods can be accomplished without specialized tools. Other methods, while requiring a special tool, can assemble connectors much faster and more reliably, and make repairs easier.\nThe number of times a connector can connect and disconnect with its counterpart while meeting all its specifications is termed as \"mating cycles\" and is an indirect measure of connector lifespan. The material used for connector contact, plating type and thickness is a major factor that determines the mating cycles.\nPlug and socket connectors.\nPlug and socket connectors are usually made up of a male plug (typically pin contacts) and a female socket (typically receptacle contacts). Often, but not always, sockets are permanently fixed to a device as in a chassis connector , and plugs are attached to a cable. \nPlugs generally have one or more pins or prongs that are inserted into openings in the mating socket. The connection between the mating metal parts must be sufficiently tight to make a good electrical connection and complete the circuit. An alternative type of plug and socket connection uses hyperboloid contacts, which makes a more reliable electrical connection. When working with multi-pin connectors, it is helpful to have a pinout diagram to identify the wire or circuit node connected to each pin.\nSome connector styles may combine pin and socket connection types in a single unit, referred to as a hermaphroditic connector. These connectors includes mating with both male and female aspects, involving complementary paired identical parts each containing both protrusions and indentations. These mating surfaces are mounted into identical fittings that freely mate with any other, without regard for gender (provided that the size and type match).\nSometimes both ends of a cable are terminated with the same gender of connector, as in many Ethernet patch cables. In other applications the two ends are terminated differently, either with male and female of the same connector (as in an extension cord), or with incompatible connectors, which is sometimes called an \"adapter cable\".\nPlugs and sockets are widely used in various connector systems including blade connectors, breadboards, XLR connectors, car power outlets, banana connectors, and phone connectors.\nJacks and plugs.\nA jack is a connector that installs on the surface of a bulkhead or enclosure, and mates with its reciprocal, the plug. According to the American Society of Mechanical Engineers, the stationary (more fixed) connector of a pair is classified as a \"jack\" (denoted J), usually attached to a piece of equipment as in a chassis-mount or panel-mount connector. The movable (less fixed) connector is classified as a \"plug\" (denoted P), designed to attach to a wire, cable or removable electrical assembly. This convention is currently defined in ASME Y14.44-2008, which supersedes IEEE 200-1975, which in turn derives from the long-withdrawn MIL-STD-16 (from the 1950s), highlighting the heritage of this connector naming convention. IEEE 315-1975 works alongside ASME Y14.44-2008 to define jacks and plugs.\nThe term \"jack\" occurs in several related terms:\nCrimp-on connectors.\nCrimped connectors are a type of solderless connection, using mechanical friction and uniform deformation to secure a connector to a pre-stripped wire (usually stranded). Crimping is used in splice connectors, crimped multipin plugs and sockets, and crimped coaxial connectors. Crimping usually requires a specialised crimping tool, but the connectors are quick and easy to install and are a common alternative to solder connections or insulation displacement connectors. Effective crimp connections deform the metal of the connector past its yield point so that the compressed wire causes tension in the surrounding connector, and these forces counter each other to create a high degree of static friction. Due to the elastic element in crimped connections, they are highly resistant to vibration and thermal shock.\nCrimped contacts are permanent (i.e. the connectors and wire ends cannot be reused).\nCrimped plug-and-socket connectors can be classified as \"rear release\" or \"front release\". This relates to the side of the connector where the pins are anchored:\nSoldered connectors.\nMany plug and socket connectors are attached to a wire or cable by soldering conductors to electrodes on the back of the connector. Soldered joints in connectors are robust and reliable if executed correctly, but are usually slower to make than crimped connections. When wires are to be soldered to the back of a connector, a backshell is often used to protect the connection and add strain relief. Metal \"solder buckets\" or \"solder cups\" are provided, which consist of a cylindrical cavity that an installer fills with solder before inserting the wire.\nWhen creating soldered connections, it is possible to melt the dielectric between pins or wires. This can cause problems because the thermal conductivity of metals causes heat to quickly distribute through the cable and connector, and when this heat melts plastic dielectric, it can cause short circuits or \"flared\" (conical) insulation. Solder joints are also more prone to mechanical failure than crimped joints when subjected to vibration and compression.\nInsulation-displacement connectors.\nSince stripping insulation from wires is time-consuming, many connectors intended for rapid assembly use insulation-displacement connectors which cut the insulation as the wire is inserted. These generally take the form of a fork-shaped opening in the terminal, into which the insulated wire is pressed, which cut through the insulation to contact the conductor. To make these connections reliably on a production line, special tools accurately control the forces applied during assembly. On small scales, these tools tend to cost more than tools for crimped connections.\nInsulation displacement connectors are usually used with small conductors for signal purposes and at low voltage. Power conductors carrying more than a few amperes are more reliably terminated with other means, though \"hot tap\" press-on connectors find some use in automotive applications for additions to existing wiring.\nA common example is the multi-conductor flat ribbon cable used in computer disk drives; to terminate each of the many (approximately 40) wires individually would be slow and error-prone, but an insulation displacement connector can terminate all the wires in a single action. Another very common use is so-called punch-down blocks used for terminating unshielded twisted pair wiring.\nBinding posts.\nBinding posts are a single-wire connection method, where stripped wire is screwed or clamped to a metal electrode. Such connectors are frequently used in electronic test equipment and audio. Many binding posts also accept a banana plug.\nScrew terminals.\nScrew connections are frequently used for semi-permanent wiring and connections inside devices, due to their simple but reliable construction. The basic principle of all screw terminals involves the tip of a bolt clamping onto a stripped conductor. They can be used to join multiple conductors, to connect wires to a printed circuit board, or to terminate a cable into a plug or socket. The clamping screw may act in the longitudinal axis (parallel to the wire) or the transverse axis (perpendicular to the wire), or both. Some disadvantages are that connecting wires is more difficult than simply plugging in a cable, and screw terminals are generally not very well protected from contact with persons or foreign conducting materials.\nTerminal blocks (also called terminal \"boards\" or \"strips\") provide a convenient means of connecting individual electrical wires without a splice or physically joining the ends. Since terminal blocks are readily available for a wide range of wire sizes and terminal quantity, they are one of the most flexible types of electrical connector available. One type of terminal block accepts wires that are prepared only by stripping a short length of insulation from the end. Another type, often called \"barrier strips\", accepts wires that have ring or spade terminal \"lugs\" crimped onto the wires.\nPrinted circuit board (PCB) mounted screw terminals let individual wires connect to a PCB through leads soldered to the board.\nRing and spade connectors.\nThe connectors in the top row of the image are known as ring terminals and spade terminals (sometimes called fork or split ring terminals). Electrical contact is made by the flat surface of the ring or spade, while mechanically they are attached by passing a screw or bolt through them. The spade terminal form factor facilitates connections since the screw or bolt can be left partially screwed in as the spade terminal is removed or attached. Their sizes can be determined by the gauge of the conducting wire, and the interior and exterior diameters.\nIn the case of insulated crimp connectors, the crimped area lies under an insulating sleeve through which the pressing force acts. During crimping, the extended end of this insulating sleeve is simultaneously pressed around the insulated area of the cable, creating strain relief. The insulating sleeve of insulated connectors has a color that indicates the wire's cross-section area. Colors are standardized according to DIN 46245:\nBlade connectors.\nA blade connector is a type of single wire, plug-and-socket connection device using a flat conductive blade (plug) that is inserted into a receptacle. Wires are typically attached to male or female blade connector terminals by either crimping or soldering. Insulated and uninsulated varieties are available. In some cases the blade is an integral manufactured part of a component (such as a switch or a speaker unit), and the reciprocal connector terminal is pushed onto the device's connector terminal.", "Engineering,_Manufacturing": 1.0000030994, "qwen": "Yes"}
{"id": "30992971", "revid": "4626", "url": "https://en.wikipedia.org/wiki?curid=30992971", "title": "Remote center compliance", "text": "In robotics, a remote center compliance, remote center of compliance or RCC is a mechanical device that facilitates automated assembly by preventing peg-like objects from jamming when they are inserted into a hole with tight clearance. In a naive design without an RCC, a robot might pick up a peg with its gripper, center the peg over the hole, and then push the peg along the axis of the hole. If the peg is perfectly aligned and centered, it would then slide into the hole. However, if the peg's alignment or centering is slightly off, the peg contacts one side of the hole first and the peg's tip experiences a lateral force. As the robot's gripper is not perfectly stiff, the peg will tend to rotate about an axis in the plane of the gripper's fingers, called the center of compliance. Such a rotation further misaligns the peg, increasing the lateral force and causing more rotation, resulting in a jam that prevents the insertion from being completed.\nThe RCC changes the way the peg responds to a lateral force at its tip. The RCC is typically placed between the robot's wrist and the gripper, though it can be built into the gripper itself. The RCC lets the gripper assembly move in the plane perpendicular to the peg's axis, allowing the peg to rotate about an axis in the plane of the top of the hole, effectively moving the center of compliance from the gripper to the hole. With the RCC, the forces generated by any misalignment move the peg in a way that corrects the problem, rather than exacerbates it.", "Engineering,_Manufacturing": 1.0000085831, "qwen": "Yes"}
{"id": "27128645", "revid": "651076", "url": "https://en.wikipedia.org/wiki?curid=27128645", "title": "Speedwire", "text": "Speedwire is a solderless prototyping system manufactured by BICC-Vero for constructing electronic circuit boards. The system is based on a circuit board pre-drilled with holes in a regular 0.1-inch (2.54 mm) square grid. The boards are available in standard sizes such as Eurocard modules. Some of the holes are through-plated and interconnected with copper strips to form power and ground rails. \nSpecial terminals are provided, which are inserted, using a special tool, into the holes in the prototyping board where components are to be fitted. Some boards are also available pre-populated with terminals. Each terminal is a metal tube with a component socket at one end and an insulation-displacement fork at the other. The component socket accepts a wire lead, such as the lead of a resistor or capacitor, or the leg of a 0.1-inch-pitch DIL package. The insulation-displacement fork accepts an insulated wire specially manufactured for the Speedwire system. The wire is pressed between the forks using a special tool. The forks cut through the insulation and grip the wire, making a gas-tight contact. The wire can then be cut off, or continued to another terminal. Wires can be pulled out of terminals and re-routed.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "67356898", "revid": "4904587", "url": "https://en.wikipedia.org/wiki?curid=67356898", "title": "Unilever Sri Lanka", "text": "Unilever Sri Lanka is a Sri Lankan consumer goods company located in Colombo. It is wholly owned by Unilever, a British multinational consumer goods company. Its products include food, beauty products, personal care, pharmaceuticals, and baby products. Unilever Sri Lanka was established in 1938 as Lever Brother Ceylon Limited. In 1972, it was renamed Unilever Sri Lanka. The company has been ranked as Most Valuable and Strongest Brand and Most Respected Entity. The company has over two dozen brands that are market leaders in Sri Lanka since the 1940s. Unilever operates from a factory complex in an industrial zone of Horana since 2012. About 96% of the company's products are manufactured locally, and more than twenty of its brands are exported outside Sri Lanka.\nAwards.\nUnilever Sri Lanka's largest factory facility, in Horana, is ISO 9001-certified. It manufactures up to 200 products, covering fourteen brands.\nIn 2015, the company won the SLIM Brand Excellence award.\nUnilever Sri Lanka has developed a plastic-free, environmentally friendly packaging system. It was awarded the first eco-friendly baby product SLS certification in 2020.", "Engineering,_Manufacturing": 0.9982506037, "qwen": "Yes"}
{"id": "67362434", "revid": "35354423", "url": "https://en.wikipedia.org/wiki?curid=67362434", "title": "QBS-09", "text": "The QBS-09 semi-automatic shotgun, also known as the Type 09 shotgun, is a semi-automatic shotgun developed by Norinco of the People's Republic of China.\nDesign and development.\nThe initial development of the QBS-09 dates back to 1989, with the project officially established in 2005. Multiple prototypes were created between 2005 and 2007, including one featuring an internal tube design, and a conventional magazine-fed design.\nThe QBS-09 uses specifically designed DBD-09 18.4mm tungsten alloy anti-personnel buckshot. The round is loaded with 14 pellets of high-density tungsten alloy buckshot set into plastic container with steel-case. Tungsten alloy is used as the penetration level of the lead pellets were unable to meet the PLA requirement. Each pellet is made of tungsten alloy ball of 5.3mm (~0.2“) in diameter, 1.4 gram (~22 grains) in weight.\nThe length of the round is 65mm and the whole round weighs 44 grams. The muzzle velocity is reported at 420 m/s (1380 fps), with an effective range of up to 100 meters. Due to the DBD-09 round generating high-impulse recoil, the QBS09 shotgun is equipped with a spring-buffered shoulder stock, which retracts every time the gun fires.\nThe Type 10 rubber round is also available as a less-lethal option. The Type 10 round weighs 33.96～39.66g, containing 28 rubber pellets with a diameter of 7.2mm. The Type 10 paintball gun is also available for law enforcement usage.", "Engineering,_Manufacturing": 0.9974141717, "qwen": "Yes"}
{"id": "18483642", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=18483642", "title": "Health hazards in semiconductor manufacturing occupations", "text": "Health hazards in semiconductor manufacturing occupations are a major issue of occupational hygiene due to the chemical hazards required to produce semiconductors in the semiconductor industry. The manifestations of exposure to health hazards during the production process often occurs at a low level and the effects of the toxins may take decades to surface.\nA Scientific Advisory Committee funded by the Semiconductor Industry Association concluded there was no evidence of increased cancer risk to cleanroom workers, although it could not rule out the possibility that circumstances might exist that could result in increased risk.\nImpacts of Health Hazards in Semiconductor Manufacturing on Women.\nHistorically, semiconductor fabrication and the production roles involved in creating integrated circuits have often been the role of women. In the 1980s, it was estimated that 68% of tech production jobs (including semiconductor production) were performed by women. In Southeast Asia, one of the largest producers of semiconductors in the world, over 90% of the production jobs were said to be filled by women during this period. Today, the trend of women dominating production roles in the semiconductor industry continues.\nSemiconductor fabrication, as previously stated, has a number of adverse impacts on workers' health. However, these effects are realized to a greater extent in female workers then with men. Digital Equipment, one American producer of semiconductors, found that women working in its factories had twice the chance of experiencing a miscarriage as compared to the general population. Subsequently, Bloomberg reported that the parent company behind Digital Equipment initially pledged to remove the teratogens from their manufacturing processes, however instead decided to outsource production to factories abroad where the regulations and public pressure for the use of these chemicals was less significant. Semiconductor producers continually subvert occupational safety and health regulations by operating abroad in countries where these regulations are lax and even nonexistent, which ultimately occurs at the detriment of the primarily female workers producing the chips.\nMany semiconductor fabrication plants are associated with causing loss of eyesight and degradation of vision capabilities in workers. One plant in Hong Kong in the 1970s reported that workers over age 25 were called \"Grandma\" as they were the most susceptible to eyesight damage from the toxic chemicals involved in semiconductor fabrication. These health impacts can often cause workers to leave semiconductor production jobs earlier than expected, yet unable to easily find other jobs after they fully experience the health impacts of semiconductor fabrication in the first place.", "Engineering,_Manufacturing": 1.0000065565, "qwen": "Yes"}
{"id": "18496885", "revid": "962242750", "url": "https://en.wikipedia.org/wiki?curid=18496885", "title": "Microdispensing", "text": "Microdispensing is the technique of producing liquid media dosages in volumes of less than one microlitre. The continuing miniaturization in almost all technical areas creates constant challenges for industry, development and research facilities. Microdispensing is one of those challenges. Ever smaller amounts of adhesive, liquid, oil, grease and a multitude of other media must be dispensed reliably and accurately in dosage and placement with short cycle times. The precise positioning and quantity of fluids such as glue, reagents or any other substance has a great influence on the overall quality of a medical device. A few examples are:\nMicrodispensing is also used in non-medical applications, like on-demand soda flavoring (the Coca-Cola Freestyle and Pepsi Spire), inkjet printing, and 3-D printing.\nDispensing techniques.\nThere are two basic types of dispensing techniques: classic contact dispensing and non-contact dispensing.\nContact dispensing.\nIn contact dispensing, the drop forms at the exit of a nozzle, and is deposited by contact, while the drop is still on the nozzle. The technique is as old as the wish to divide a medium, stored in a big container, into smaller amounts. A good example for this is applying adhesive with a tube: To apply the adhesive requires contact between the tip of the tube and the part for the bead of adhesive to be transferred. This method has disadvantages:\nDespite all of these disadvantages, contact dispensing is still used in the majority of automated processes today, because of:\nTypical technologies for contact dispensing.\nGear pump\nPressure-time systems\nNon-contact dispensing (Jetting).\nIn non-contact dispensing, the drop also forms at the end of a nozzle, but far enough away from the target area that the drop separates from the nozzle before it hits. This, too, is a very old technique, as old as squirting liquid from a tube.\nBecause of increasing requirements in regards to cycle time and accuracy in almost all areas of production, non-contact dispensing is constantly gaining importance. A good example for this is the attachment of very small electronic parts (SMD parts) onto printed circuit boards and substrates. For this, the part carrier only needs to be positioned in one plane - after that the adhesive can be transferred without contact. The following examples show the advantages of non-contact dispensing:\nNon-contact dispensing can be divided in two different methods:\nJet-forming dispensing.\nJet-forming dispensing exists when the flow velocity of a medium at the nozzle exit is high enough that the effects of gravitation and surface tension on the separation of the fluid from the nozzle are of secondary importance. This state is characterized by the Weber number:\nwhere\nThe physical border line between drop- and jet-forming is around a Weber-number of 8. At this point the dynamic pressure of the flowing medium exceeds the pressure from the surface tension of the drop, which therefore sticks to the nozzle. This transitional stage can be demonstrated at a water tap by gradually increasing the flow, going from the dropping status until a continuous water jet has formed. The Weber-number in this case is, however, clearly above 8, because of the jet exit conditions of the nozzle.\nBy using the Weber-number, the theoretical lower limit of the mass flow can be found for the jet-forming conditions. In actual applications, to assure a safe dispensing process, the real Weber-numbers chosen should be between 20 and 50.\nFor a calculated estimation of the fluid flow velocity in the nozzle, for fluids with Newtonian flow behavior, the formula for capillary fluid flow according to the Hagen–Poiseuille law has been proven.\nTo avoid atomizing of the fluid at the nozzle exit, the fluid flow in the nozzle must be laminar, which is the case as long as the Reynolds number (Re) of the nozzle is smaller than the critical Reynolds-number of the nozzle:\nReynolds-number of the nozzle:\nCritical Reynolds-number of the nozzle:\nThus, the theoretical range of the jet-forming dispension is enclosed at its lower limit by the Weber-number and at its upper limit by the critical Reynolds-number. For practical applications, a high kinetic energy in the fluid jet is not desirable, because the jet probably would burst and spatter tiny droplets around the target point. Jet-forming dispensing systems are therefore usually operated in the area of lower Weber-numbers.\nIn practice, the calculation of the Weber-number becomes more complicated when fluids with additives are used, which demonstrate a non-Newtonian (i.e. thixotropic) flow behavior and therefore the viscosity during the flow through the nozzle is different.\nDynamic drop dispensing.\nDynamic drop dispensing is characterised by separation of a drop from the nozzle exit through a dynamic process, because the static pressure of the liquid medium is insufficient for forming a fluid jet.\nA well-known example is inkjet printing. In this application, the volume of a small dispensing chamber with adjoining nozzle becomes reduced through a short impulse, whereby the ink is ejected through the nozzle. Nozzle chamber, nozzle and ink reservoir are hereby fluidically connected without any valve in between. During the dispensing process, some of the medium is also flowing in the reverse direction (back into the reservoir). The surface tension of the fluid at the nozzle exit prevents air being sucked in and fluid from exiting the nozzle when the dispensing chamber is filled up again. The principle of this process is only useful for low-viscosity fluids and this principle is not applicable with higher fluid pressures.\nInk-jet systems have the following inherent properties:\n• Very small single-drop volumes are achievable (8 picolitres)\n• High dispensing frequencies can be realised (some kHz)\n• Low costs for mass production\n• Only certain low-viscosity media are dispensable (i.e. no volatile media)\n• Principally not leak-proof\nFor industrial production, the dispensing amounts and the range of viscosity spectra of ink-jet systems for most applications are too small. In these fields of production, specially-designed valves with tappet drives of high dynamic pressure are used instead. These microdispensing systems are characterised by the following properties:\n• Single drop volumes from 10 to 200 nanolitres\n• Dispensing frequencies up to 100 Hz\n• Dispensing accuracy < 1%\n• Media viscosities up to 200 Pa·s (thixotropic)", "Engineering,_Manufacturing": 0.9999685287, "qwen": "Yes"}
{"id": "18506279", "revid": "1152682103", "url": "https://en.wikipedia.org/wiki?curid=18506279", "title": "Blanking and piercing", "text": "Blanking and piercing are shearing processes in which a punch and die are used to produce parts from coil or sheet stock. Blanking produces the outside features of the component, while piercing produces internal holes or shapes. The web is created after multiple components have been produced and is considered scrap material. The \"slugs\" produced by piercing internal features are also considered scrap. The terms \"piercing\" and \"punching\" can be used interchangeably.\nDie roll and burr formation.\nBurrs and die roll are typical features of stamped components. Die roll is created when the material being stamped in compressed before the material begins to shear. Die roll takes the form of a radius around the outside edge of the blank and the pierced holes. After compression, the part shears for about 10% of the part thickness, and then fractures free of the strip or sheet. This fracturing produces a raised, jagged edge which is called a \"burr\". Burrs are typically removed by tumbling in a secondary process. Burr height can be used as an important indicator of tool wear.\nTooling design guidelines.\nThe selection criteria of all process parameters are governed by the sheet thickness and by the strength of the work-piece material being pierced.\nThe punch/die clearance is a crucial parameter, which determines the load or pressure experienced at the cutting edge of the tool, commonly known as point pressure. Excessive point pressure can lead to accelerated wear and ultimately failure. the surface quality of the trimmed edge is severely affected by the clearance, too.\nMaterial specific design guidelines are developed by companies in order to define the minimum acceptable values of hole diameters, bridge sizes, slot dimensions. Similarly, the strip lay-out must be determined (strip width and pitch). The bridge width between the parts and the edge allowance between the part and the edge of the strip also have to be selected.\nA simple operation may only need a pancake die. While many dies perform complex procedures simultaneously, a pancake die may only perform one simple procedure with the finished product being removed by hand. \nProcess variants.\nThere are various types of blanking and piercing: lancing, perforating, notching, nibbling, shaving, cutoff, and dinking.\nLancing.\nLancing is a piercing operation in which the workpiece is sheared and bent with one strike of the die. A key part of this process is that there is not reduction of material, only a modification in its geometry. This operation is used to make tabs, vents, and louvers.\nThe cut made in lancing is not a closed cut, like in perforation even though a similar machine is used, but a side is left connected to be bent sharply or in more of a rounded manner.\nLancing can be used to make partial contours and free up material for other operations further down the production line. Along with these reasons, lancing is also used to make tabs (where the material is bent at a 90 degree angle to the material), vents (where the bend is around 45 degrees), and louvers (where the piece is rounded or cupped). Lancing also helps to cut or slight shear of sheet on cylindrical shape.\nNormally lancing is done on a mechanical press, lancing requires the use of punches and dies to be used. The different punches and dies determine the shape and angle (or curvature) of the newly made section of the material. The dies and punches are needed to be made of tool steel to withstand the repetitious nature of the procedure.\nPerforating.\nPerforating is a piercing tooling that involves punching a large number of closely spaced holes.\nNotching.\nNotching is a piercing operation that removes material from the edge of the workpiece.\nNibbling.\nThe nibbling process cuts a contour by producing a series of overlapping slits or notches. A nibbler may be employed to do this. This allows for complex shapes to be formed in sheet metal up to 6 mm (0.25 in) thick using simple tools. that is essentially a small punch and die that reciprocates quickly; around 300–900 times per minute. Punches are available in various shape and sizes; oblong and rectangular punches are common because they minimize waste and allow for greater distances between strokes, as compared to a round punch. Nibbling can occur on the exterior or interior of the material, however interior cuts require a hole to insert the tool.\nThe process is often used on parts that do not have quantities that can justify a dedicated blanking die. The edge smoothness is determined by the shape of the cutting die and the amount the cuts overlap; naturally the more the cuts overlap, the cleaner the edge. For added accuracy and smoothness, most shapes created by nibbling undergo filing or grinding processes after completion.\nShaving.\nThe shaving process is a finishing operation where a small amount of metal is sheared away from an already blanked part. Its main purpose is to obtain better dimensional accuracy, but secondary purposes include squaring the edge and smoothing the edge. Blanked parts can be shaved to an accuracy of up to 0.025 mm (0.001 in).\nShaving of metals is done in order to remove excess or scrap metal. A straight, smooth edge is provided and therefore shaving is frequently performed on instrument parts, watch and clock parts, and the like. Shaving is accomplished in shaving dies especially designed for the purpose.\nTrimming.\nThe trimming operation is the last operation performed, because it cuts away excess or unwanted irregular features from the walls of drawn sheets.\nFine blanking.\nFine blanking is a specialized form of blanking where there is no fracture zone when shearing. This is achieved by compressing the whole part and then an upper and lower punch extract the blank. This allows the process to hold very tight tolerances, and perhaps eliminate secondary operations.\nMaterials that can be fine blanked include aluminium, brass, copper, and carbon, alloy, and stainless steels.\nFine blanking presses are similar to other metal stamping presses, but they have a few critical additional parts. A typical compound fine blanking press includes a hardened die punch (male), the hardened blanking die (female), and a guide plate of similar shape/size to the blanking die. The guide plate is the first applied to the material, impinging the material with a sharp protrusion or \"stinger\" around the perimeter of the die opening. Next, a counter pressure is applied opposite the punch, and finally, the die punch forces the material through the die opening. Since the guide plate holds the material so tightly, and since the counter pressure is applied, the material is cut in a manner more like extrusion than typical punching. Mechanical properties of the cut benefit similarly with a hardened layer at the cut edge of the part. Because the material is so tightly held and controlled in this setup, part flatness remains very true, distortion is nearly eliminated, and edge burr is minimal. Clearances between the die and punch are generally around 1% of the cut material thickness, which typically varies between . Currently parts as thick as can be cut using fine blanking. Tolerances between ± are possible, depending on the base material thickness and tensile strength, and part layout.\nWith standard compound fine blanking processes, multiple parts can often be completed in a single operation. Parts can be pierced, partially pierced, offset (up to 75°), embossed, or coined, often in a single operation. Some combinations may require progressive fine blanking operations, in which multiple operations are performed at the same pressing station. Due to the higher lifetime, blanking punches are usually covered by PVD protective coatings. \nThe advantages of fine blanking are:\nOne of the main advantages of fine blanking is that slots or holes can be placed very near to the edges of the part, or near to each other. Also, fineblanking can produce holes that are much smaller (as compared to material thickness) than can be produced by conventional stamping.\nThe disadvantages are:", "Engineering,_Manufacturing": 1.0, "qwen": "Yes"}
{"id": "5946462", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=5946462", "title": "National Centre for Food Manufacturing", "text": "The National Centre for Food Manufacturing (NCFM) is the food science campus of the University of Lincoln, situated on \"Park Road\" at Holbeach in the south of the county of Lincolnshire. It offers part-time apprenticeships and distance learning degrees for individuals working in the food industry.\nApprenticeships, Degree and Foundation Courses.\nThe National Centre for Food Manufacturing offers part time distance learning options to achieve Foundation and BSc (Honours) Food Manufacture degrees and higher degrees through research together with all levels of apprenticeships including Higher Apprenticeships (which includes a Foundation Degree). The Foundation and Undergraduate degrees cover areas including Food and Drink Operations and Manufacturing Management - Food Science and Technology – and Food Supply Chain Management. The Centre also offers part time Masters and PhDs - often progressed by food sector employees and focused on specific Food Manufacturing Industry Challenges.\nThe Higher and Degree Apprenticeships include the CMDA (Chartered Manager Degree Apprenticeship), Departmental Manager, Laboratory Scientist and Professional Technical degrees.\nThe Centre provides support to apprentices for Functional Skills development in maths and English as required by their relevant apprenticeship standard and offers employers a complete skills development programme for its employees.\nNCFM has apprenticeship partnerships with 250 UK food businesses including Addo Food Group, Bakkavor, Bidfood, Dalehead Foods, Summers Butchery Services, Greencore Group, Tulip, Dovecote Park, Fresttime, Finlays, JDM Food Group, Kerry, Nestle, Worldwide Fruit, University Academy Holbeach, Produce World Group, J.O. Sims Ltd, Greenvale AP, FreshLinc, Ripe Now and Lincolshire Field Products.\nResearch.\nNCFM advances food manufacturing and related food supply chain research initiatives via a wide range of industry and academic partnerships. The areas of core research include Robotics and Automation, Food Analysis (Microbiology & Food Chemistry), Advanced Food Processing Technologies, Food Insights & Sustainability, and Food Supply Chain Development.\nThe NCFM Research and Technical Resources coupled with industry and academic partnerships enable NCFM to readily progress multidisciplinary research and practical problem solving for the food industry. NCFM’s research agenda reflects the food sector’s innovation priorities and is informed by funding partners and directly by the needs of the diverse food sector including retailers and food businesses of all sizes from multinationals to SME and micro businesses. Research at NCFM is funded by a number of sources (dependent upon the specific challenge) including direct consultancy with business, Innovate UK, BBSRC, EPSRC, FSA, EU Interreg programmes and Horizon 2020 initiatives.\nShort Courses.\nNCFM offers Short Courses including courses in auditing, food safety, Hazard analysis and critical control points(HACCP), health and safety, management and team development, and technical and product development.\nCommercial Partners.\nThe National Centre for Food Manufacturing maintains commercial partnerships with food industry organisations specialising in areas such as robotics, refrigeration, sustainability, packaging, manufacturing, innovative food supply chain management, food processing, productivity and several other areas.\nConferencing Facilities.\n‌The National Centre for Food Manufacturing Holbeach campus offers facilities hire for conferences, seminars and exhibitions.", "Engineering,_Manufacturing": 0.9812348485, "qwen": "Yes"}
{"id": "19377", "revid": "22942118", "url": "https://en.wikipedia.org/wiki?curid=19377", "title": "Microelectronics", "text": "Microelectronics is a subfield of electronics. As the name suggests, microelectronics relates to the study and manufacture (or microfabrication) of very small electronic designs and components. Usually, but not always, this means micrometre-scale or smaller. These devices are typically made from semiconductor materials. Many components of a normal electronic design are available in a microelectronic equivalent. These include transistors, capacitors, inductors, resistors, diodes and (naturally) insulators and conductors can all be found in microelectronic devices. Unique wiring techniques such as wire bonding are also often used in microelectronics because of the unusually small size of the components, leads and pads. This technique requires specialized equipment and is expensive.\nDigital integrated circuits (ICs) consist of billions of transistors, resistors, diodes, and capacitors. Analog circuits commonly contain resistors and capacitors as well. Inductors are used in some high frequency analog circuits, but tend to occupy larger chip area due to their lower reactance at low frequencies. Gyrators can replace them in many applications.\nAs techniques have improved, the scale of microelectronic components has continued to decrease. At smaller scales, the relative impact of intrinsic circuit properties such as interconnections may become more significant. These are called parasitic effects, and the goal of the microelectronics design engineer is to find ways to compensate for or to minimize these effects, while delivering smaller, faster, and cheaper devices.\nToday, microelectronics design is largely aided by Electronic Design Automation software.", "Engineering,_Manufacturing": 0.9997285008, "qwen": "Yes"}
{"id": "34799585", "revid": "136926", "url": "https://en.wikipedia.org/wiki?curid=34799585", "title": "Accumulative roll bonding", "text": "Accumulative roll bonding (ARB) is a severe plastic deformation (SPD) process. It is a method of rolling a stack of metal sheets, which are repeatedly rolled to a severe reduction ratio, sectioned into two halves, piled again and rolled. It has been often proposed as a method for the production of metal materials with ultrafine grain microstructure. The earliest works on ARB were by Nobuhiro Tsuji, Y. Saito and co-workers. To obtain a single slab of a solid material, the rolling involves not only deformation, but also roll bonding.", "Engineering,_Manufacturing": 1.0000042915, "qwen": "Yes"}
{"id": "17181411", "revid": "41503339", "url": "https://en.wikipedia.org/wiki?curid=17181411", "title": "Multilayer soft lithography", "text": "Multilayer soft lithography (MSL) is a fabrication process in which microscopic chambers, channels, valves and vias are molded within bonded layers of elastomer.\nCommercial PDMS stamps can mold materials such as optical adhesive in a sequential process to create the bonded layers.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "24618690", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=24618690", "title": "Circle grid analysis", "text": "Circle grid analysis (CGA), also known as circle grid strain analysis, is a method of measuring the strain levels of sheet metal after a part is formed by stamping or drawing. The name itself is a fairly accurate description of the process. Literally, a grid of circles of known diameter is etched to the surface of the sheet metal to be formed. After the part is formed, the circles have been stretched into ellipses. By measuring the longest part of the ellipse (called the “major strain”) and the shortest part of the ellipse (called the “minor strain”), it is possible to determine how close any stamped part is to splitting or fracturing. \nThe goal of using circle grid strain analysis is to predict potential problems before they become problems. Once you have a forming problem, chances are circle grid analysis won’t be able to help you, unless it’s intermittent enough to form a “good” part from time to time.", "Engineering,_Manufacturing": 1.0000056028, "qwen": "Yes"}
{"id": "33070424", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=33070424", "title": "Manufacturing Grocers' Employees' Federation of Australia", "text": "Manufacturing Grocers' Employees' Federation of Australia (M.G.U.) was an Australian trade union existing between 1906 and 1988. The union was first established as the Federated Candle, Soap, Soda & Starch Employees' Union of Australia, before changing its name in 1914. The union represented workers employed in manufacturing grocers' sundries and non-edible grocery products, particularly in the southern states of South Australia and Victoria. In 1988 the union amalgamated with the Federated Millers and Mill Employees' Union to form the Federated Millers and Manufacturing Grocers Employees' Association of Australia, which in turn merged with a number of unions to form the National Union of Workers.\nActivities.\nThe Manufacturing Grocers' Union undertook a wide variety of activities to pursue the interests of its members. The union made representations to government and the public in favour of protectionist measures to ensure the competitiveness of products manufactured in Australia with international imports. The M.G.U. also publicised the poor working conditions of its members, including problems such as noise, dust and physical fatigue. The South Australian trade union leader and later politician Theo Nicholls served as part-time secretary of the union in South Australia, and was active in its organisation.\nIndustrial disputes.\nThe Manufacturing Grocers' Union underwent several bitter industrial disputes during its history, including a number of strikes. The first major strike the union was involved in was in April 1916, when the M.G.U., along with a number of other unions, participated in a sympathy strike with the Storemen and Packers' Union over the dismissal of several men at a Parsons' Brothers factory in Melbourne. The strike lasted for several months and led to shortages of several products in Victoria, due to blockade of goods by the employers. The strike eventually collapsed in June 1916, with all strikers returning to work.\nThe Manufacturing Grocers' Union held another major strike in 1948 at the match factories of Bryant and May, in Richmond, Melbourne, over an increase in the required daily output of matches. The dispute was resolved when all parties agreed to allow the Commonwealth Statistician determine a fair daily output per worker.\nDemarcation disputes.\nThe Manufacturing Grocers' Union made efforts to establish a branch of the union in New South Wales, the most populous state of Australia, but this attempt was thwarted by the Australian Workers' Union, who represented the relevant workers at the time.\nAmalgamation.\nIn 1988 the Manufacturing Grocers' Union amalgamated with the Federated Millers and Mill Employees' Union, another small union representing workers in food processing. The resulting body, the Federated Millers and Manufacturing Grocers Employees' Association of Australasia, was short-lived and subsequently amalgamated with the National Union of Storeworkers, Packers, Rubber and Allied Workers to form the National Union of Workers.", "Engineering,_Manufacturing": 0.9999088049, "qwen": "Yes"}
{"id": "33086131", "revid": "13037279", "url": "https://en.wikipedia.org/wiki?curid=33086131", "title": "Caldie", "text": "Caldie is a chromium-molybdenum-vanadium alloyed tool steel manufactured by Uddeholms AB. It is intended for cold work processes, such as blanking and piercing, applied to difficult materials such as advanced high strength steel, where compressive strength and chipping and cracking resistance are important.\nComposition.\nThe steel's composition is\nProperties.\nUddeholm Caldie is characterized by:\nApplication areas.\nUddeholm Caldie is suitable for short to medium run tooling where chipping and/or cracking are the predominant failure mechanisms and where a high compressive strength (hardness of over 60 HRC) is necessary. This makes Uddeholm Caldie very suitable for severe cold work applications where the combination of a hardness above 60 HRC and a high cracking resistance is of utmost importance e.g. as in the blanking and forming of ultra high strength steel sheets. Uddeholm Caldie is also very suitable as a substrate steel for applications where surface coatings are desirable or necessary.\nThis steel can be used in engineering applications where high compressive strength has to be combined with high ductility/toughness. Knives for fragmentation of plastics and metals and roll forming rolls are good examples", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "13875472", "revid": "55225", "url": "https://en.wikipedia.org/wiki?curid=13875472", "title": "Flash welding", "text": "Flash welding is a type of resistance welding that does not use any filler metals. The pieces of metal to be welded are set apart at a predetermined distance based on material thickness, material composition, and desired properties of the finished weld. Current is applied to the metal, and the gap between the two pieces creates resistance and produces the arc required to melt the metal. Once the pieces of metal reach the proper temperature, they are pressed together, effectively forge welding them together.\nParameters.\nAccording to a study published in Materials and Design, several parameters affect the final product. Flash time is the time that the arc is present. Upset time is the amount of time that the two pieces are pressed together. Flash time needs to be long enough to sufficiently heat the metal before it is pressed together. However, if it is too long, too much of the base metal begins to melt away. The upset time is critical in creating the desired mechanical properties of the finished weld. During the upset, any impurities in the base metal are pressed out creating a perfect weld. If the upset time is too short, some of the impurities may remain in the base metal creating a defective weld. The upset time is also crucial in the strength of the finished weld because it is during the upset that coalescence occurs between the two pieces of metal. If the upset time is too short, the two pieces of metal may not completely bond.\nVery often flash butt welding is controlled by distance rather than time such that the flashing would occur for a pre-determined length, say 5 mm, before the upsetting cycle starts. Upsetting may then also be controlled by distance. A parameter would be set to apply the upsetting force until a certain distance has been upset. It is generally the upsetting distance that is more important than the upsetting time.\nAt the end of upsetting there is commonly a 'hold time' during which the joint is held still to allow the joint to cool and the two pieces of metal to completely bond.\nApplications.\nRailroads use flash welding to join sections of mainline rail together to create Long Welded Rail (LWR) in a factory setting or continuous welded rail (CWR) in track, which is much smoother than mechanically-joined rail because there are no gaps between the sections of rail. This smoother rail reduces the wear on the rails themselves, effectively reducing the frequency of inspections and maintenance. Continuous welded rail is particularly used on high-speed rail lines because of the smoothness of the rail head. Flash welding is also beneficial because it allows dissimilar metals, including non ferrous metals, to be joined. This allows switches and crossings, which are generally composed of high manganese steel, to be effectively welded to carbon steel rail with the use of a stainless steel insert, while keeping the desired mechanical properties of both the rails and the crossings intact. The ability of this single process to weld many different metals, with simple parameter adjustments, makes it very versatile. Flash welding is also used in the metal building industry to increase the length of the angle iron used to fabricate joists.\nThe aluminum industry uses flash welding to join aluminum, steel, and copper in various current-carrying conductors called busbars. The steel is used for strength, the copper is used for conductivity, and the aluminum is used for its combination of cost and conductivity.", "Engineering,_Manufacturing": 0.9999821186, "qwen": "Yes"}
{"id": "13877578", "revid": "12683541", "url": "https://en.wikipedia.org/wiki?curid=13877578", "title": "Unit load", "text": "The term unit load refers to the size of an assemblage into which a number of individual items are combined for ease of storage and handling, for example a pallet load represents a unit load which can be moved easily with a pallet jack or forklift truck, or a container load represents a unit for shipping purposes. A unit load can be packed tightly into a warehouse rack, intermodal container, truck or boxcars, yet can be easily broken apart at a distribution point, usually a distribution center, wholesaler, or retail store for sale to consumers or for use.\nFunction.\nMost consumer and industrial products move through the supply chain in unitized or unit load form for at least part of their distribution cycle. Unit loads make handling, storage, and distribution more efficient. They help reduce handling costs and damage by reducing individual handling.\nA typical unit load might consist of corrugated fiberboard boxes stacked on a pallet or slip sheet and stabilized with stretch wrap, pressure-sensitive tape, strapping or shrink wrap. About 2 billion unit loads are in daily use in the United States.\nUnit load design.\nThere are three kinds of unit load design: component-based, systems-based, and standards-compliant. These have different applications.\nComponent-based design.\nComponent-based design is the outmoded \"ad hoc\" method of unit load design. Components are sometimes over-specified to get assured performance, or tested to get inexpensive economic performance.\nUnit load storage and distribution systems consist of several interacting parts: \nConsiderable knowledge exists regarding the design of each of these components: their interactions have more recently been studied. When packaging, pallet, and handling systems are designed separately at different locations by different teams, the result might be inefficient unit load systems.\nThe consequences of independent component-based design in the supply chain can include:\nSystems-based design.\nSystems-based design is a proven process of unit load component cost optimization based on an understanding of how the pallet, packaging and material handling equipment interact during product distribution and storage to design the unit load component parts.\nA systems-based approach to unit load design uses software tools and lab testing to create a package that uses just the right amount of material to protect the product, make for safe handling and transportation and minimize the use of non-recyclable materials.\nCompanies must now consider sustainability when determining how their packaging products will be reused or recycled at the end of their journey. By combining sustainability with unit load science, they not only create the optimal unit load, but also reduce the amount of packaging material used to transport that load, maximizing the materials that can be recycled and minimizing what goes into a landfill.\nUnit loads move via an unpredictable combination of many types of vehicles and storage areas, and the exact set is difficult to predict. Therefore, unit loads must be designed to travel by any such vehicles, and be stored in a wide variety of places. There are many similarities in the requirements for long-term storage and long-distance transportation of unit loads.\nFactors considered in unit load systems-based design include:\nOften a few inexpensive additions to the packaging can stabilize or stiffen a critical part and give good unit-load performance at a low cost.\nStandards-compliant design.\nStandards permit a unit load to be designed and tested to meet a written specification or test method. A unit load can be verified to comply with a standard and validated to determine that the unit load is indeed effective.\nStandards provide institutional memory of the many conditions in real logistic trains, and collect the best practices for design and testing unit loads. Standards also describe load requirements, so that logistic providers can plan to meet them.\nASTM D4169 has standard test protocols for unit loads. These vary based on the value of the load, the expected hazards, and the distribution environment. This is a performance-based standard.\nAnother standard for unit loads is MIL-STD-1660, a standard for ammunition unit loads. DOD unit loads generally use pallets, which unfortunately do not pack efficiently into ISO containers. They weigh less than to limit the stresses on handling equipment. They are weatherproof, and stack high. They often use steel pallets, steel straps with notched seals, outdoor plywood, and plastic film. MIL-STD-1660 mandates that loads must never be less than the width of a pallet, while permitting some overhang. The markings are LOGMARS bar codes and standard inventory numbers. The standard describes major parts of the logistic path, including storage, ship, air, truck, forklift and sling (i.e. ship-to-ship and parachute). There are auxiliary standards for ship-to-ship transfers, and amphibious transfers. There are tests for stacking, transport, sling, forklift and pallet jack, impact, drop tests, tip, water-retention (i.e. weather), and safe disassembly.\nMIL-STD-1660 at first looks like overdesign to commercial unit-load designers. However, similar marking standards, safety, stability, volumetric efficiency, weight limits and impact resistance are routinely needed in commercial logistics. Sling handling is routine for small ports and noncontainer transports. Weatherproofness could be optional. It is sometimes valuable, and the baggies are cheap. High, standardized stacking could be optional as well. It is expensive, but sometimes valuable for rackless and military customers.", "Engineering,_Manufacturing": 1.0000047684, "qwen": "Yes"}
{"id": "54613586", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=54613586", "title": "Cutting tool material", "text": "Cutting tool materials are materials that are used to make cutting tools which are used in machining (drill bits, tool bits, milling cutters, etc.) but not other cutting tools like knives or punches.\nCutting tool materials must be harder than the material of the workpiece, even at high temperatures during the process.\nThe following properties are required for cutting tool\nThere is no material that shows all of these properties at the same time. Very hard materials, have lower toughness and break more easily. The following cutting tool materials are used:", "Engineering,_Manufacturing": 1.0000060797, "qwen": "Yes"}
{"id": "54630510", "revid": "1158549967", "url": "https://en.wikipedia.org/wiki?curid=54630510", "title": "NPP Istok", "text": "Istok State Scientific Production  is a company (scientific production association) based in Fryazino, Russia. It is part of the Ruselectronics group. \nIstok is a major producer of electronic components for space and military use, including magnetrons, klystrons, high-powered vacuum tubes, carbon dioxide lasers, electro-optical devices. It has also developed and manufactured consumer products for the national economy since the 1960s.\nFor 2020, the company implemented the IIoT.ISTOK Industrial Internet of Things system, which monitors technical processes", "Engineering,_Manufacturing": 0.9999382496, "qwen": "Yes"}
{"id": "54648113", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=54648113", "title": "Thyssenkrupp Materials Services", "text": "thyssenkrupp Materials Services GmbH (tkMX) is the lead company of the business area of the same name and part of the diversified German industrial group thyssenkrupp AG. Materials Services is a global materials distributor as well as a technical and infrastructural service provider for the B2B-sector. The total revenue in the fiscal year 2015/2016 was 11.88 billion Euro.\nCompany structure.\nthyssenkrupp Materials Services is divided in three so-called business units - Materials Distribution, Supply Chain Services and Special Materials. Over 19,700 employees work for the 81 Materials Services subsidiaries at around 480 branches in more than 40 countries.\nMain customers are located in Europe and North America. They are specialist retailers and companies of the automotive sector or the metal processing industry.\nDigital transformation.\nMaterials Services runs a Digital Transformation Office (DTO). The DTO forwards the business area’s digitalization goals. The strategy includes a progressive addition of e-commerce models as well as a cultural change to an integral and collaborative work environment.\nThe online shop \"materials4me\" was launched in Great Britain, Germany, Spain and Switzerland in 2016. The target group of materials4me are do-it-yourselfers, educational institutions as well as small and medium businesses. There are also two B2B-portals. \"Materials Services Online-Portal\" grants access to order documents, among others, for key accounts. On the website \"onlinelaserworks\" customers can upload CAD drawings to have blanks fully automatically cut to size.\nAt the Hannover trade fair thyssenkrupp announced the opening of a production center for Additive Manufacturing (3D-printing) in the city Mülheim in 2017.\nIn 2017, Materials Services also announced the self-developed platform \"toii\" in line with the Industrial Internet of Things (IIoT). This system is compatible with old and new machines from different manufactures. The tool should accelerate the automation of the production operations as well as make processes much more efficient.", "Engineering,_Manufacturing": 1.0000009537, "qwen": "Yes"}
{"id": "693342", "revid": "1170098033", "url": "https://en.wikipedia.org/wiki?curid=693342", "title": "Numerical control", "text": "Numerical control (also computer numerical control, abbreviated CNC) is the automated control of machining tools (such as drills, lathes, mills, grinders, routers and 3D printers) by means of a computer. A CNC machine processes a piece of material (metal, plastic, wood, ceramic, stone, or composite) to meet specifications by following coded programmed instructions and without a manual operator directly controlling the machining operation.\nA CNC machine is a motorized maneuverable tool and often a motorized maneuverable platform, which are both controlled by a computer, according to specific input instructions. Instructions are delivered to a CNC machine in the form of a sequential program of machine control instructions such as G-code and M-code, and then executed. The program can be written by a person or, far more often, generated by graphical computer-aided design (CAD) or computer-aided manufacturing (CAM) software. In the case of 3D printers, the part to be printed is \"sliced\" before the instructions (or the program) are generated. 3D printers also use G-Code.\nCNC offers greatly increased productivity over non-computerized machining for repetitive production, where the machine must be manually controlled (e.g. using devices such as hand wheels or levers) or mechanically controlled by pre-fabricated pattern guides (see pantograph mill). However, these advantages come at significant cost in terms of both capital expenditure and job setup time. For some prototyping and small batch jobs, a good machine operator can have parts finished to a high standard whilst a CNC workflow is still in setup.\nIn modern CNC systems, the design of a mechanical part and its manufacturing program are highly automated. The part's mechanical dimensions are defined using CAD software and then translated into manufacturing directives by computer-aided manufacturing (CAM) software. The resulting directives are transformed (by \"post processor\" software) into the specific commands necessary for a particular machine to produce the component and then are loaded into the CNC machine.\nSince any particular component might require the use of several different tools – drills, saws, etc. – modern machines often combine multiple tools into a single \"cell\". In other installations, several different machines are used with an external controller and human or robotic operators that move the component from machine to machine. In either case, the series of steps needed to produce any part is highly automated and produces a part that meets every specification in the original CAD drawing, where each specification includes a tolerance.\nDescription.\nMotion is controlling multiple axes, normally at least two (X and Y), and a tool spindle that moves in the Z (depth). The position of the tool is driven by direct-drive stepper motors or servo motors to provide highly accurate movements, or in older designs, motors through a series of step-down gears. Open-loop control works as long as the forces are kept small enough and speeds are not too great. On commercial metalworking machines, closed-loop controls are standard and required to provide the accuracy, speed, and repeatability demanded.\nParts description.\nAs the controller hardware evolved, the mills themselves also evolved. One change has been to enclose the entire mechanism in a large box as a safety measure (with safety glass in the doors to permit the operator to monitor the machine's function), often with additional safety interlocks to ensure the operator is far enough from the working piece for safe operation. Most new CNC systems built today are 100% electronically controlled.\nCNC-like systems are used for any process that can be described as movements and operations. These include laser cutting, welding, friction stir welding, ultrasonic welding, flame and plasma cutting, bending, spinning, hole-punching, pinning, gluing, fabric cutting, sewing, tape and fiber placement, routing, picking and placing, and sawing.\nHistory.\nThe first CNC machines were built in the 1940s and 1950s, based on existing tools that were modified with motors that moved the tool or part to follow points fed into the system on punched tape. These early servomechanisms were rapidly augmented with analog and digital computers, creating the modern CNC machine tools that have revolutionized machining processes.\nOther CNC tools.\nMany other tools have CNC variants, including:\nTool/machine crashing.\nIn CNC, a \"crash\" occurs when the machine moves in such a way that is harmful to the machine, tools, or parts being machined, sometimes resulting in bending or breakage of cutting tools, accessory clamps, vises, and fixtures, or causing damage to the machine itself by bending guide rails, breaking drive screws, or causing structural components to crack or deform under strain. A mild crash may not damage the machine or tools but may damage the part being machined so that it must be scrapped. Many CNC tools have no inherent sense of the absolute position of the table or tools when turned on. They must be manually \"homed\" or \"zeroed\" to have any reference to work from, and these limits are just for figuring out the location of the part to work with it and are no hard motion limit on the mechanism. It is often possible to drive the machine outside the physical bounds of its drive mechanism, resulting in a collision with itself or damage to the drive mechanism. Many machines implement control parameters limiting axis motion past a certain limit in addition to physical limit switches. However, these parameters can often be changed by the operator.\nMany CNC tools also do not know anything about their working environment. Machines may have load sensing systems on spindle and axis drives, but some do not. They blindly follow the machining code provided and it is up to an operator to detect if a crash is either occurring or about to occur, and for the operator to manually abort the active process. Machines equipped with load sensors can stop axis or spindle movement in response to an overload condition, but this does not prevent a crash from occurring. It may only limit the damage resulting from the crash. Some crashes may not ever overload any axis or spindle drives.\nIf the drive system is weaker than the machine's structural integrity, then the drive system simply pushes against the obstruction, and the drive motors \"slip in place\". The machine tool may not detect the collision or the slipping, so for example the tool should now be at 210mm on the X-axis, but is, in fact, at 32mm where it hit the obstruction and kept slipping. All of the next tool motions will be off by −178mm on the X-axis, and all future motions are now invalid, which may result in further collisions with clamps, vises, or the machine itself. This is common in open-loop stepper systems but is not possible in closed-loop systems unless mechanical slippage between the motor and drive mechanism has occurred. Instead, in a closed-loop system, the machine will continue to attempt to move against the load until either the drive motor goes into an overload condition or a servo motor fails to get to the desired position.\nCollision detection and avoidance are possible, through the use of absolute position sensors (optical encoder strips or disks) to verify that motion occurred, or torque sensors or power-draw sensors on the drive system to detect abnormal strain when the machine should just be moving and not cutting, but these are not a common component of most hobby CNC tools. Instead, most hobby CNC tools simply rely on the assumed accuracy of stepper motors that rotate a specific number of degrees in response to magnetic field changes. It is often assumed the stepper is perfectly accurate and never missteps, so tool position monitoring simply involves counting the number of pulses sent to the stepper over time. An alternate means of stepper position monitoring is usually not available, so crash or slip detection is not possible.\nCommercial CNC metalworking machines use closed-loop feedback controls for axis movement. In a closed-loop system, the controller monitors the actual position of each axis with an absolute or incremental encoder. Proper control programming will reduce the possibility of a crash, but it is still up to the operator and programmer to ensure that the machine is operated safely. However, during the 2000s and 2010s, the software for machining simulation has been maturing rapidly, and it is no longer uncommon for the entire machine tool envelope (including all axes, spindles, chucks, turrets, tool holders, tailstocks, fixtures, clamps, and stock) to be modeled accurately with 3D solid models, which allows the simulation software to predict fairly accurately whether a cycle will involve a crash. Although such simulation is not new, its accuracy and market penetration are changing considerably because of computing advancements.\nNumerical precision and equipment backlash.\nWithin the numerical systems of CNC programming, the code generator can assume that the controlled mechanism is always perfectly accurate, or that precision tolerances are identical for all cutting or movement directions. This is not always a true condition of CNC tools. CNC tools with a large amount of mechanical backlash can still be highly precise if the drive or cutting mechanism is only driven to apply cutting force from one direction, and all driving systems are pressed tightly together in that one cutting direction. However, a CNC device with high backlash and a dull cutting tool can lead to cutter chatter and possible workpiece gouging. The backlash also affects the precision of some operations involving axis movement reversals during cutting, such as the milling of a circle, where axis motion is sinusoidal. However, this can be compensated for if the amount of backlash is precisely known by linear encoders or manual measurement.\nThe high backlash mechanism itself is not necessarily relied on to be repeatedly precise for the cutting process, but some other reference object or precision surface may be used to zero the mechanism, by tightly applying pressure against the reference and setting that as the zero references for all following CNC-encoded motions. This is similar to the manual machine tool method of clamping a micrometer onto a reference beam and adjusting the Vernier dial to zero using that object as the reference.\nPositioning control system.\nIn numerical control systems, the position of the tool is defined by a set of instructions called the part program. Positioning control is handled using either an open-loop or a closed-loop system. In an open-loop system, communication takes place in one direction only: from the controller to the motor. In a closed-loop system, feedback is provided to the controller so that it can correct for errors in position, velocity, and acceleration, which can arise due to variations in load or temperature. Open-loop systems are generally cheaper but less accurate. Stepper motors can be used in both types of systems, while servo motors can only be used in closed systems.\nCartesian coordinates.\nThe G & M code positions are all based on a three-dimensional Cartesian coordinate system. This system is a typical plane often seen in mathematics when graphing. This system is required to map out the machine tool paths and any other kind of actions that need to happen in a specific coordinate. Absolute coordinates are what are generally used more commonly for machines and represent the (0,0,0) point on the plane. This point is set on the stock material to give a starting point or \"home position\" before starting the actual machining.\nCoding.\nG-codes.\nG-codes are used to command specific movements of the machine, such as machine moves or drilling functions. The majority of G-Code programs start with a percent (%) symbol on the first line, then followed by an \"O\" with a numerical name for the program (i.e. \"O0001\") on the second line, then another percent (%) symbol on the last line of the program. The format for a G-code is the letter G followed by two to three digits; for example G01. G-codes differ slightly between a mill and lathe application, for example:\nM-codes.\n[Code Miscellaneous Functions (M-Code)]. M-codes are miscellaneous machine commands that do not command axis motion. The format for an M-code is the letter M followed by two to three digits; for example:\nExample.\nO0001\nG20 G40 G80 G90 G94 G54(Inch, Cutter Comp. Cancel, Deactivate all canned cycles, moves axes to machine coordinate, feed per min., origin coordinate system)\nM06 T01 (Tool change to tool 1)\nG43 H01 (Tool length comp. in a positive direction, length compensation for the tool)\nM03 S1200 (Spindle turns CW at 1200RPM)\nG00 X0. Y0. (Rapid Traverse to X=0. Y=0.)\nG00 Z.5 (Rapid Traverse to z=.5)\nG00 X1. Y-.75 (Rapid traverse to X1. Y-.75)\nG01 Z-.1 F10 (Plunge into part at Z-.25 at 10in per min.)\nG03 X.875 Y-.5 I.1875 J-.75 (CCW arc cut to X.875 Y-.5 with radius origin at I.625 J-.75)\nG03 X.5 Y-.75 I0.0 J0.0 (CCW arc cut to X.5 Y-.75 with radius origin at I0.0 J0.0)\nG03 X.75 Y-.9375 I0.0 J0.0(CCW arc cut to X.75 Y-.9375 with radius origin at I0.0 J0.0)\nG02 X1. Y-1.25 I.75 J-1.25 (CW arc cut to X1. Y-1.25 with radius origin at I.75 J-1.25)\nG02 X.75 Y-1.5625 I0.0 J0.0 (CW arc cut to X.75 Y-1.5625 with same radius origin as the previous arc)\nG02 X.5 Y-1.25 I0.0 J0.0 (CW arc cut to X.5 Y-1.25 with same radius origin as the previous arc)\nG00 Z.5 (Rapid traverse to z.5)\nM05 (spindle stops)\nG00 X0.0 Y0.0 (Mill returns to origin)\nM30 (Program End)\nHaving the correct speeds and feeds in the program provides for a more efficient and smoother product run. Incorrect speeds and feeds will cause damage to the tool, machine spindle, and even the product. The quickest and simplest way to find these numbers would be to use a calculator that can be found online. A formula can also be used to calculate the proper speeds and feeds for a material. These values can be found online or in Machinery's Handbook.", "Engineering,_Manufacturing": 1.0000054836, "qwen": "Yes"}
{"id": "4304767", "revid": "1079762635", "url": "https://en.wikipedia.org/wiki?curid=4304767", "title": "Economic production quantity", "text": "The economic production quantity model (also known as the EPQ model) determines the quantity a company or retailer should order to minimize the total inventory costs by balancing the inventory holding cost and average fixed ordering cost. The EPQ model was developed by E.W. Taft in 1918. \nThis method is an extension of the economic order quantity model (also known as the EOQ model). The difference between these two methods is that the EPQ model assumes the company will produce its own quantity or the parts are going to be shipped to the company while they are being produced, therefore the orders are available or received in an incremental manner while the products are being produced. While the EOQ model assumes the order quantity arrives complete and immediately after ordering, meaning that the parts are produced by another company and are ready to be shipped when the order is placed. \nIn some literature, \"economic manufacturing quantity\" model (EMQ) is used for \"economic production quantity\" model (EPQ). Similar to the EOQ model, EPQ is a single product lot scheduling method. A multiproduct extension to these models is called \"product cycling problem\".\nOverview.\nEPQ only applies where the demand for a product is constant over the year and that each new order is delivered/produced incrementally when the inventory reaches zero. There is a fixed cost charged for each order placed, regardless of the number of units ordered. There is also a holding or storage cost for each unit held in storage (sometimes expressed as a percentage of the purchase cost of the item).\nWe want to determine the optimal number of units of the product to order so that we minimize the total cost associated with the purchase, delivery and storage of the product\nThe required parameters to the solution are the total demand for the year, the purchase cost for each item, the fixed cost to place the order and the storage cost for each item per year. Note that the number of times an order is placed will also affect the total cost, however, this number can be determined from the other parameters\nTotal cost function and derivation of EPQ formula.\nWhere formula_3 is the average inventory level, and formula_4 is the average holding cost. Therefore, multiplying these two results in the holding cost per year.\nWhere formula_6 are the orders placed in a year, multiplied by K results in the ordering cost per year.\nWe can notice from the equations above that the total ordering cost decreases as the production quantity increases. Inversely, the total holding cost increases as the production quantity increases. Therefore, in order to get the optimal production quantity we need to set holding cost per year equal to ordering cost per year and solve for quantity (Q), which is the EPQ formula mentioned below. Ordering this quantity will result in the lowest total inventory cost per year.\n ", "Engineering,_Manufacturing": 0.9864111543, "qwen": "Yes"}
{"id": "4312474", "revid": "34421687", "url": "https://en.wikipedia.org/wiki?curid=4312474", "title": "Laminated object manufacturing", "text": "Laminated object manufacturing (LOM) is a rapid prototyping system developed by Helisys Inc. (Cubic Technologies is now the successor organization of Helisys) In it, layers of adhesive-coated paper, plastic, or metal laminates are successively glued together and cut to shape with a knife or laser cutter. Objects printed with this technique may be additionally modified by machining or drilling after printing. Typical layer resolution for this process is defined by the material feedstock and usually ranges in thickness from one to a few sheets of copy paper.\nProcess.\nThe process is performed as follows:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "52428611", "revid": "44123155", "url": "https://en.wikipedia.org/wiki?curid=52428611", "title": "Hoshin Kanri", "text": "Hoshin Kanri (Japanese: 方針管理, \"policy management\") is a 7-step process used in strategic planning in which strategic goals are communicated throughout the company and then put into action. The Hoshin Kanri strategic planning system originated from post-war Japan, but has since spread to the U.S. and around the world. Translated from Japanese, Hoshin Kanri aptly means \"compass management\". The individual words \"hoshin\" and \"kanri\" mean direction and administration, respectively.\nOverview.\nHoshin Kanri requires a strategic vision in order to succeed. From there, strategic objectives need to be clearly defined, with goals being written for long periods of a one to five-year-long timeframe. Once the long term timeframe goals are completed, the team can focus on yearly objectives. Management needs to avoid picking too many vital goals in order to stay focused on what is strategically important. The big goals then need to be broken down into smaller goals, at a weekly and monthly basis and then implemented so that everyone, from management to the factory floor, is in agreement on what needs to be accomplished. The satisfaction of goals should be reviewed on a monthly basis, with a larger annual review at the end of the year. Performance measurement is also a key part of the process.\nHoshin Kanri is a top-down approach, with the goals being mandated by management and the implementation being performed by employees. As a result, systems need to be in place to ensure that objectives from senior management are effectively communicated all the way down the chain of command. As such, a catchball system is often used in order to aid in the execution of the strategic plan. A catchball system seeks to get opinions of both managers and employees through meetings and interactions in order to ensure the bidirectional flow of goals, feedback, and other information throughout the organization.\nUsage.\nCompanies that use Hoshin Kanri often follow a Think, Plan, Implement, and Review process, which is comparable to W. Edwards Deming's Plan Do Check Act cycle. This is because Deming played a role in the spreading of quality control principles that influenced the development of Hoshin Kanri. The cyclical process is a way to plan for the future, not just to react to what is happening now. The principles of PDCA are heavily embedded into the Hoshin Kanri planning process. Beyond PDCA, Joseph M. Juran also played a role in spreading quality control principles that influenced Hoshin Kanri, specifically focusing on management's role in the process. \nThe Hoshin Kanri technique is often aided with a Hoshin Kanri Matrix, on which companies list and align their various-length objectives and goals. The matrix can also incorporate Key Performance Indicators and priority values and be accompanied by detailed plans, resource assignment demands, or value stream maps. ", "Engineering,_Manufacturing": 0.9975652099, "qwen": "Yes"}
{"id": "13470639", "revid": "45772480", "url": "https://en.wikipedia.org/wiki?curid=13470639", "title": "DMG Mori Seiki Co.", "text": "DMG Mori Co., Ltd. (DMG森精機株式会社, DMG Mori Seiki Kabushiki-gaisha) (formerly Mori Seiki Co., Ltd. and DMG Mori Seiki Co., Ltd.) is a Japanese company headquartered in Tokyo and Nara City, engaged primarily in the manufacture and sale of machine tools. Since its establishment, DMG Mori has become the largest machine tool builder in the world.\nHistory.\nDMG Mori Co., Ltd. was founded in 1948 by the three Mori brothers. It originally produced textile machinery, but in 1958, the company entered the machine tool manufacturing industry, and by 1968, it began manufacturing numerical control (NC) lathes. \nIn 2001, grinding machine manufacturer Taiyo Koki joined the DMG Mori Group and in 2002, DMG Mori Co., Ltd. acquired business assets of Hitachi Seiki in Japan. In November 2009, the U.S. headquarters were inaugurated during a four-day event.\nIn the same year, Mori Seiki Co., Ltd. entered into a strategic partnership with Germany's Gildemeister AG, which controlled the brand DMG. As a result, the US operations of both companies were merged into one unit on April 1, 2010. This partnership with Gildemeister AG led to the renaming of the two entites with the same name of DMG Mori in 2013, and in 2016, the Japanese company acquired majority shares of the German company.\nIn June 2018, the Tokyo Digital Innovation Center (DIC) was established, along with the opening of a new plant in Pleszew, Poland the same year.\nCompany Structure.\nDMG Mori Co., Ltd. is directed by President , has a revenue of 3,418 million Euros and employs 12,626 individuals internationally. The company has a dual headquarters system, with headquarters located in Shiomi, Koto-ku, Tokyo (Global headquarters) and in Nara City, Nara Prefecture. \nThe corporate governance structure is that of a Japanese Kabushiki-gaisha.\nDMG Mori has a sales, service and engineering network with 16 Production sites and 113 Sales and Services sites in 43 countries and a leading global market share of 10%.\nThe shareholders of the DMG Mori Co., Ltd. are Baillie Gifford & Co. (10.0%), Global Alpha Capital Management Ltd. (7.5%), Sumitomo Mitsui Trust Asset Management Co., Ltd. (3.7%), DMG Mori Seiki Employee Stock Ownership Plan (3.6%), Nomura Asset Management Co., Ltd. (3.2%), Mori Masashiko/Mori Seiki (2.8%), Mori Manufacturing Research & Technology Foundation (2.7%), BlackRock Fund Advisors (2.7%), The Vanguard Group, Inc. (2.1%) and Norges Bank Investment Management (1.6%).\nDMG Mori AG.\nDMG Mori AG, headquartered in Bielefeld, Germany, is headed by Alfred Geißler as CEO and had revenues of 2,365.7 million Euros in 2022.\nDMG Mori Co., Ltd., through its subsidiary, holds 87.37 % of the shares in its subsidiary DMG Mori AG. \nDMG Mori AG has a supervisory board, which holds a higher rank than the executive board. This supervisory board is entrusted with the tasks of appointing directors and approving major business plans and investments.\nDMG MORI Production sites.\nDMG Mori has production sites in Japan (Nara Campus, Iga Campus, Taiyo Koki and Magnescale), Germany (Pfronten, Seebach, Bielefeld and Stipshausen), Italy (Bergamo and Tortona), Poland (Pleszew) and the USA (Davis). The sites in Germany are run by the group companies Deckel Maho (Pfronten and Seebach), Gildemeister (Bielefeld) and Sauer (Stipshausen). The group companies Gital (Bergamo) and Graziano (Tortona) manage the sites in Italy and Famot (Pleszew) runs the base in Poland. DMG Mori also has a manufacturing partner in India, Lakshmi Machine Works Limited. The company also operated a plant in Ulyanovsk, Russia. In response to the Russian invasion of Ukraine in 2022, DMG Mori has withdrawn from the Russian market.\nProducts and Technologies.\nDMG Mori produces and distributes machine tools, corresponding products and measuring instruments. The company manufactures numerically controlled (NC) machine tools like high-speed precision lathes, as well as horizontal and vertical machining centers (MCs), among other machine tools designed for diverse functions. It also deals with machining centers, repair and restoration, engineering services and software. \nThe company provides 5-axis and multi-axis machines and automation and digitization solutions. It installed 100,000 machines internationally and builds 8,000 to 10,000 machines a year.\nSports Involvement.\nDMG Mori has partnered with Red Bull Racing Honda since 2012, and also had a partnership with the Toyota Gazoo Racing World Rally Team. In 2020, the DMG Mori Sailing Team completed the Vendée Globe as the first Asian team with Kojiro Shiraishi as skipper.", "Engineering,_Manufacturing": 0.9952743053, "qwen": "Yes"}
{"id": "13479680", "revid": "38339096", "url": "https://en.wikipedia.org/wiki?curid=13479680", "title": "Reorder point", "text": "The reorder point (ROP) is the level of inventory which triggers an action to replenish that particular inventory stock. It is a minimum amount of an item which a firm holds in stock, such that, when stock falls to this amount, the item must be reordered. It is normally calculated as the forecast usage during the replenishment lead time plus safety stock. In the EOQ (Economic Order Quantity) model, it was assumed that there is no time lag between ordering and procuring of materials.\nContinuous Review System.\nThe reorder point for replenishment of stock occurs when the level of inventory drops down to zero. In view of instantaneous replenishment of stock the level of inventory jumps to the original level from zero level.\nIn real life situations one never encounters a zero lead time. There is always a time lag from the date of placing an order for material and the date on which materials are received. As a result the reorder point is always higher than zero, and if the firm places the order when the inventory reaches the reorder point, the new goods will arrive before the firm runs out of goods to sell. The decision on how much stock to hold is generally referred to as the order point problem, that is, how low should the inventory be depleted before it is reordered.\nThe two factors that determine the appropriate order point are the delivery time stock which is the Inventory needed during the lead time (i.e., the difference between the order date and the receipt of the inventory ordered) and the safety stock which is the minimum level of inventory that is held as a protection against shortages due to fluctuations in demand.\nTherefore: Reorder Point = Normal consumption during lead-time + Safety Stock .\nSeveral factors determine how much delivery time stock and safety stock should be held. In summary, the efficiency of a replenishment system affects how much delivery time is needed. Since the delivery time stock is the expected inventory usage between ordering and receiving inventory, efficient replenishment of inventory would reduce the need for delivery time stock. And the determination of level of safety stock involves a basic trade-off between the risk of stockout, resulting in possible customer dissatisfaction and lost sales, and the increased costs associated with carrying additional inventory.\nAnother method of calculating reorder level involves the calculation of usage rate per day, lead time which is the amount of time between placing an order and receiving the goods and the safety stock level expressed in terms of several days' sales.\nReorder level = Average daily usage rate × lead-time in days .\nFrom the above formula it can be easily deduced that an order for replenishment of materials be made when the level of inventory is just adequate to meet the needs of production during lead-time.\nExample.\nIf the average daily usage rate of a material is 50 units and the lead-time is seven days, then:\nReorder level = Average daily usage rate × Lead time in days = 50 units per day × 7 days = 350 units\nWhen the inventory level reaches 350 units an order should be placed for material. By the time the inventory level reaches zero towards the end of the seventh day from placing the order materials will reach and there is no cause for concern.\nReorder point = Average Lead Time*Average Demand + Service Level*\nMore information on above formulation is given here:\nhttp://scm.ncsu.edu/scm-articles/article/reorder-point-formula-inventory-management-models-a-tutorial\nReorder point = S × L + J (S × R × L)\nWhere\nSee also.\nRe-order in Aviation is calculated based on actual usage.\nResources.\nReorder Point Software freeware. Use it for simulations and studies.", "Engineering,_Manufacturing": 0.9998819828, "qwen": "Yes"}
{"id": "13480873", "revid": "42425010", "url": "https://en.wikipedia.org/wiki?curid=13480873", "title": "Digital prototyping", "text": "Digital Prototyping gives conceptual design, engineering, manufacturing, and sales and marketing departments the ability to virtually explore a complete product before it's built. Industrial designers, manufacturers, and engineers use Digital Prototyping to design, iterate, optimize, validate, and visualize their products digitally throughout the product development process. Innovative digital prototypes can be created via CAutoD through intelligent and near-optimal iterations, meeting multiple design objectives (such as maximised output, energy efficiency, highest speed and cost-effectiveness), identifying multiple figures of merit, and reducing development gearing and time-to-market. Marketers also use Digital Prototyping to create photorealistic renderings and animations of products prior to manufacturing. Companies often adopt Digital Prototyping with the goal of improving communication between product development stakeholders, getting products to market faster, and facilitating product innovation.\nDigital Prototyping goes beyond simply creating product designs in 3D. It gives product development teams a way to assess the operation of moving parts, to determine whether or not the product will fail, and see how the various product components interact with subsystems—either pneumatic or electric. By simulating and validating the real-world performance of a product design digitally, manufacturers often can reduce the number of physical prototypes they need to create before a product can be manufactured, reducing the cost and time needed for physical prototyping. Many companies use Digital Prototyping in place of, or as a complement to, physical prototyping.\nDigital Prototyping changes the traditional product development cycle from design>build>test>fix to design>analyze>test>build. Instead of needing to build multiple physical prototypes and then testing them to see if they'll work, companies can conduct testing digitally throughout the process by using Digital Prototyping, reducing the number of physical prototypes needed to validate the design. Studies show that by using Digital Prototyping to catch design problems up front, manufacturers experience fewer change orders downstream. Because the geometry in digital prototypes is highly accurate, companies can check interferences to avoid assembly issues that generate change orders in the testing and manufacturing phases of development. Companies can also perform simulations in early stages of the product development cycle, so they avoid failure modes during testing or manufacturing phases. With a Digital Prototyping approach, companies can digitally test a broader range of their product's performance. They can also test design iterations quickly to assess whether they're over- or under-designing components.\nResearch from the Aberdeen Group shows that manufacturers that use Digital Prototyping build half the number of physical prototypes as the average manufacturer, get to market 58 days faster than average, and experience 48 percent lower prototyping costs.\nHistory of Digital Prototyping.\nThe concept of Digital Prototyping has been around for over a decade, particularly since software companies such as Autodesk, PTC, Siemens PLM (formerly UGS), and Dassault began offering computer-aided design (CAD) software capable of creating accurate 3D models.\nIt may even be argued that the product lifecycle management (PLM) approach was the harbinger of Digital Prototyping. PLM is an integrated, information-driven approach to a product's lifecycle, from development to disposal. A major aspect of PLM is coordinating and managing product data among all software, suppliers, and team members involved in the product's lifecycle. Companies use a collection of software tools and methods to integrate people, data, and processes to support singular steps in the product's lifecycle or to manage the product's lifecycle from beginning to end. PLM often includes product visualization to facilitate collaboration and understanding among the internal and external teams that participate in some aspect of a product's lifecycle.\nWhile the concept of Digital Prototyping has been a longstanding goal for manufacturing companies for some time, it's only recently that Digital Prototyping has become a reality for small-to-midsize manufacturers that cannot afford to implement complex and expensive PLM solutions.\nDigital Prototyping and PLM.\nLarge manufacturing companies rely on PLM to link otherwise unconnected, siloed activities, such as concept development, design, engineering, manufacturing, sales, and marketing. PLM is a fully integrated approach to product development that requires investments in application software, implementation, and integration with enterprise resource planning (ERP) systems, as well as end-user training and a sophisticated IT staff to manage the technology. PLM solutions are highly customized and complex to implement, often requiring a complete replacement of existing technology. Because of the high expense and IT expertise required to purchase, deploy, and run a PLM solution, many small-to-midsized manufacturers cannot implement PLM.\nDigital Prototyping is a viable alternative to PLM for these small-to-midsized manufacturers. Like PLM, Digital Prototyping seeks to link otherwise unconnected, siloed activities, such as concept development, design, engineering, manufacturing, sales, and marketing. However, unlike PLM, Digital Prototyping does not support the entire product development process from conception to disposal, but rather focuses on the design-to-manufacture portion of the process. The realm of Digital Prototyping ends when the digital product and the engineering bill of materials are complete. Digital Prototyping aims to resolve many of the same issues as PLM without involving a highly customized, all-encompassing software deployment. With Digital Prototyping, a company may choose to address one need at a time, making the approach more pervasive as its business grows. Other differences between Digital Prototyping and PLM include:\nDigital Prototyping Workflow.\nA Digital Prototyping workflow involves using a single digital model throughout the design process to bridge the gaps that typically exist between workgroups such as industrial design, engineering, manufacturing, sales, and marketing. Product development can be broken into the following general phases at most manufacturing companies:\nConceptual Design.\nThe conceptual design phase involves taking customer input or market requirements and data to create a product design. In a Digital Prototyping workflow, designers work digitally, from the very first sketch, throughout the conceptual design phase. They capture their designs digitally, and then share that data with the engineering team using a common file format. The industrial design data is then incorporated into the digital prototype to ensure technical feasibility.\nIn a Digital Prototyping workflow, designers and their teams review digital design data via high-quality digital imagery or renderings to make informed product design decisions. Designers may create and visualize several iterations of design, changing things like materials or color schemes, before a concept is finalized.\nEngineering.\nDuring the engineering phase of the Digital Prototyping workflow, engineers create the product's 3D model (the digital prototype), integrating design data developed during the conceptual design phase. Teams also add electrical systems design data to the digital prototype while it's being developed, and evaluate how different systems interact. At this stage of the workflow, all data related to the product's development is fully integrated into the digital prototype. Working with mechanical, electrical, and industrial design data, companies engineer every last product detail in the engineering phase of the workflow. At this point, the digital prototype is a fully realistic digital model of the complete product.\nEngineers test and validate the digital prototype throughout their design process to make the best possible design decisions and avoid costly mistakes. Using the digital prototype, engineers can:\nBy incorporating integrated calculations, stress, deflection, and motion simulations into the Digital Prototyping workflow, companies can speed development cycles by minimizing physical prototyping phases. By implementing a digital prototype of a partially or fully automated vehicle and its sensor suite into a dynamic co-simulation of traffic flow and vehicle dynamics, a novel toolchain methodology comprising virtual testing is available for the development of automated driving functions by the automotive industry.\nAlso during the engineering phase of the Digital Prototyping workflow, engineers create documentation required by the production team.\nManufacturing.\nIn a Digital Prototyping workflow, manufacturing teams are involved early in the design process. This input helps engineers and manufacturing experts work together on the digital prototype throughout the design process to ensure that the product can be produced cost effectively. Manufacturing teams can see the product exactly as it's intended, and provide input on manufacturability. Companies can perform molding simulations on digital prototypes for plastic part and injection molds to test the manufacturability of their designs, identifying potential manufacturing defects before they cut mold tooling.\nDigital Prototyping also enables product teams to share detailed assembly instructions digitally with manufacturing teams. While paper assembly drawings can be confusing, 3D visualizations of digital prototypes are unambiguous. This early and clear collaboration between manufacturing and engineering teams helps minimize manufacturing problems on the shop floor.\nFinally, manufacturers can use Digital Prototyping to visualize and simulate factory-floor layouts and production lines. They can check for interferences to detect potential issues such as space constraints and equipment collisions.\nCustomer Involvement.\nCustomers are involved throughout the Digital Prototyping workflow. Rather than waiting for a physical prototype to be complete, companies that use Digital Prototyping bring customers into the product development process early. They show customers realistic renderings and animations of the product's digital prototype so they'll know what the product looks like and how it will function. This early customer involvement helps companies get sign-off up front, so they don't waste time designing, engineering, and manufacturing a product that doesn't fulfill the customer's expectations.\nMarketing.\nUsing 3D CAD data from the digital prototype, companies can create realistic visualizations, renderings, and animations to market products in print, on the web, in catalogues, or in television commercials. Without needing to produce expensive physical prototypes and conduct photo shoots, companies can create virtual photography and cinematography nearly indistinguishable from reality. One aspect of this is creating the illumination environment for the subject, an area of new development.\nRealistic visualizations not only help marketing communications, but the sales process as well. Companies can respond to requests for proposals and bid on projects without building physical prototypes, using visualizations to show the potential customer what the end product will be like. In addition, visualizations can help companies bid more accurately by making it more likely that everyone has the same expectations about the end product. Companies can also use visualizations to facilitate the review process once they've secured the business. Reviewers can interact with digital prototypes in realistic environments, allowing for the validation of design decisions early in the product development process.\nConnecting Data and Teams.\nTo support a Digital Prototyping workflow, companies use data management tools to coordinate all teams at every stage in the workflow, streamline design revisions and automate release processes for digital prototypes, and manage engineering bills of materials. These data management tools connect all workgroups to critical Digital Prototyping data.\nDigital Prototyping and Sustainability.\nCompanies increasingly use Digital Prototyping to understand sustainability factors in new product designs, and to help meet customer requirements for sustainable products and processes. They minimize material use by assessing multiple design scenarios to determine the optimal amount and type of material required to meet product specifications. In addition, by reducing the number of physical prototypes required, manufacturers can trim down their material waste.\nDigital Prototyping can also help companies reduce the carbon footprint of their products. For example, WinWinD, a company that creates innovative wind turbines, uses Digital Prototyping to optimize the energy production of wind-power turbines for varying wind conditions. Furthermore, the rich product data supplied by Digital Prototyping can help companies demonstrate conformance with the growing number of product-related environmental regulations and voluntary sustainability standards.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "8549047", "revid": "45382375", "url": "https://en.wikipedia.org/wiki?curid=8549047", "title": "Magnetic pulse welding", "text": "Magnetic pulse welding (MPW) is a solid state welding process that uses magnetic forces to weld two workpieces together. The welding mechanism is most similar to that of explosion welding.\nMagnetic pulse welding started in the early 1970s, when the automotive industry began to use solid state welding. The biggest advantage using magnetic pulse welding is that the formation of brittle intermetallic phases is avoided. Therefore, dissimilar metals can be welded, which cannot be effectively joined by fusion welding. With magnetic pulse welding high quality welds in similar and dissimilar metals can be made in microseconds without the need for shielding gases or welding consumables.\nProcess.\nMagnetic pulse welding is based on a very short electromagnetic pulse (capacitors through low inductance switches into a coil. The pulsed current with a very high amplitude and frequency (500 kA and 15 kHz) produces a high-density magnetic field, which creates an eddy current in one of the work pieces. Repulsive Lorentz forces are created and a high magnetic pressure well beyond the material yield strength causing acceleration and one of the work pieces impacts onto the other part with a collision velocity up to .\nDuring magnetic pulse welding a high plastic deformation is developed along with high shear strain and oxide disruption thanks to the jet and high temperatures near the collision zone. This leads to solid state weld due to the microstructure refinement, dislocation cells, slip bends, micro twins and local recrystallization.\nPrinciples.\nIn order to get a strong weld, several conditions have to be reached:\nThe main difference between magnetic pulse welding and explosive welding is that the collision angle and the velocity are almost constant during the explosive welding process, while in magnetic pulse welding they continuously vary.\nNumerical simulations of MPW.\nVarious numerical investigations were carried out to predict the interface behavior of the MPW and the in-flight behavior of the flyer to determine the collision conditions. Generally, the flyer velocity prior to the impact governs the interfacial phenomena. This is the characteristic parameter that should be known based on the process and adjustable process parameters. Although, Experimental measurements using laser velocimetry methods provide an accurate assessment of the flyer velocity, (one example of such measurement is Photon Doppler velocimetry (PDV)), numerical computation offers a better description of the flyer velocity in terms of spatial and temporal distribution. Moreover, a multi-physics computation of the MPW process take into account of the electrical current through the coil and compute the physical behavior for an electromagnetic-mechanical coupled problem. Sometime, these simulations also allow to include the thermal effect during the process. A 3D example model used for LS-DYNA simulation is also described in , and it also provides some details of the physical interactions of the process, the governing equations, the resolution procedure, and both boundary and initial conditions. The model is used to show the capability of 3D computation to predict the process behavior and particularly, the flyer kinematics and macroscopic deformation.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "42356790", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=42356790", "title": "Evolution of management systems", "text": "This article outlines the evolution of management systems. A management system is the framework of processes and procedures used to ensure that an organization can fulfill all tasks required to achieve its objectives.\nAfter World War II, the reigning paradigm of product-oriented mass production had reached its peak. Examples of management systems at that time are linear assembly lines, organizational hierarchies of command, product quality control and mass consumption.\nSoon afterwards, the Deming-Juran process-quality teachings spearheaded a new quality orientation (later referred to as Total quality management) and propelled Japan directly to the post-war process focus (process quality control, just-in-time, continuous improvement). The US responded by a painful and prolonged product-to-process transformation, ultimately leveling the playing field again by the mid 1980s.\nAt the end of the 1980s, business process reengineering focused on the radical redesign of the production process through the reintegration of task, labor and knowledge. As a result, lean, flexible and streamlined production processes were created, capable of fast response and internet-based integration necessary for the upcoming phase of supply chains - business-to-business (B2B) – as well as demand chains – business-to-customer (B2C). \nIn the above three stages of evolution of management systems, the competitive advantage was derived almost exclusively from the internal resources of the firm. At the end of the 1980s, a radical fourth shift has occurred: the competitive advantage became increasingly derived from the external resources of the firm – through the extended networks of suppliers and customers.\nFigure 1 refers to the basic scheme of production and service delivery process. It represents the traditional linear input-process-output management system. This system has been fixed and unchanging for centuries. The only change has been in terms of changing focus on individual components of the system, emphasizing different parts of this basic scheme.\nAlthough the scheme itself (inputs → process → outputs) remains mostly unchallenged, there are some indications that this business model will undergo major restructurings in the future (in the emerging stages of evolution of management systems). It will become disaggregated and distributed, subjected to non-linear modularity and bringing forth new ways of making things and delivering services. Then it will become reintegrated again, tying together globally distributed components into a unified recycling whole.\nEarly stages.\nAll early stages are characterized by changing focus of attention within the unchanging, invariant scheme of Figure 1. The management system has typically focused on:\nFinal product.\nThe final product is a primary focus, the production process is considered secondary. Its operations and their sequences are technologically fixed or ‘given’. Product quality is ‘inspected in’, mostly at the end of the process. Statistical quality control, inventory control, cost minimization, mass production, assembly line, work specialization, hierarchies of command, mass consumption, statistical mass markets and forecasting are among the defining characteristics of this stage.\nPartitioned process.\nIt is the high-quality process that assures the high-quality product. The main focus was on improving of process operations. Quality of the process was understood as the quality of its operations. Powerful new concepts of Total Quality Management (TQM), Continuous Improvement Process (Kaizen) and Just-In-Time (JIT) systems have characterized this stage. Although the operations were being improved, the process architecture and structural sequencing were kept intact and remained technologically ‘given’.\nIntegrated process.\nThe focus of attention shifted from operations (circles) to linkages (arrows) – thus changing the process architecture itself. The reengineering of the process, re-integrating individual components into effective, more autonomous and even self-manageable wholes, has characterized this stage. The production process became a business process and therefore subject to qualitative redesign and reengineering (BPR). Discontinuous improvement and process innovation replaced the piecemeal continuous improvement. Traditional vertical hierarchies of command have flattened out into more horizontal, process-oriented networks. Mass customization, disintermediation, knowledge management and autonomous teams have started emerging.\nExtended process.\nFigure 2 refers to the paradigmatic shift from internal processes expanded into the extended process – including supplier networks and alliances as well as customer self-service, mass customization and disintermediation – as the increasingly external sources of competitive advantage.\nIn this recently peaked stage, networks of suppliers and communities of customers have extended the internal process into a functional and competitive whole. Both internal and external sources of knowledge and competitiveness have formed new core competencies. Supply and demand chains management have emerged, in dependence on shifting CIP (Customer Intervention Point). Intranets and extranets have provided a communication medium for B2B and B2C exchanges. Quality has become bundled together with cost, speed and reliability..\nToday, powerful processes of global sourcing bring forth and foster a new set of relationships with customers and suppliers. The firm starts disaggregating its production processes, transferring, leasing or selling selected pieces off to a higher-added value operator or coordinator. Any firm can be only as good as is the network of which it is a part. Consequently, the firm has disaggregated and became a network.\nDistributed process.\nThis emerging stage represents the most radical business refocusing so far. Through the global sourcing, sections and components of the internal process are being outsourced to external providers and contractors in search of the highest added value contribution. Long-term alliances are formed and companies are transforming themselves into networks. Network cooperation is replacing corporate competition: \"coopetition\" emerges. The majority of companies (also the educational and training institutions) could still be the leading global players in this incessant and accelerating paradigm shifting. Globally distributed process ushers in new forms of organization, coordination and modular integration.\nDifferent parts of the extended process are geographically distributed and often spatially remote. In Figure 3, this distribution is represented by sections OS of the process which have been outsourced to higher added-value providers.\nAlthough the Stage 5 (Figure 3) represents the most radical business refocusing emerging so far, still rapidly emerging kernels of the next stage (Figure 4) is taking shape. The evolutionary process, driven by relentless global search for maximum added value, is clearly accelerating. Management systems paradigm or business model, after a century of relative invariance, is becoming a new dynamic source of competitive advantage. Radically distributed supply and demand chains of Stage 5 will clearly have to be coordinated and reintegrated on a global scale. Reintegration processes are proceeding under increasing environmental pressures. The search for added value, after exploring traditional global resources, is now turning towards reuse, recycling, recovery and remanufacturing as new sources of maximizing added value. Innovation in business models will become a norm.\nRecycled process.\nDuring the process of utilizing added value, the asset-recovery practices expand quickly to a majority of products and services (Dell, IBM, Xerox). New products are being designed for extended life spans and multiple profit cycles. Reverse logistics and reverse logistics management (RLM) are adding new loops to the traditionally unidirectional processes of supply chains. Old supply chains have become demand chains and now reverse value chains, demonstrating that value can be added in both directions: through the forward pass of production as well as through the backward pass of recovery and remanufacture. Concepts of easy disassembly, durability, reuse and recycling are built in into equipment design.\nFigure 4 refers to closed-loop management system and it represents the Stage 6 of the evolution of management systems. The new loops in the figure are not just traditional information feedback loops, but real business processes of collection, disassembly, reprocessing and reassembly activities (operations). The conventional open-ended linear processes are being redesigned towards closure.\nNew loops of recycled products and materials, energy recovery and knowledge renewal are being created within global-sourcing (GS) networks. Product reuse/remanufacture relies on a high residual value which gives a good head start for added value maximization. The system becomes organizationally closed and potentially long-term sustainable or even trans-generations self-sustainable. The \"openness\" and customization of the product design, upgradeable products, flexible product platforms, mutability and waste-free strategies are being implemented. However, in this latest stage, new employee skills and managerial knowledge, as well as essential mass customization mindset are yet to be produced, maintained and renewed. Eliminating non-value added resources is still necessary. Integrating production system elements and work functions still needs time to evolve.\nEvolutionary spiral.\nEvolutionary spiral of the six management systems (SMS) are indicated in Figure 5.\nIt is appropriate to notice that six-management-system evolution is progressing in an accelerated fashion, the periods of stasis are getting shorter and revolutions are occurring faster. Individual management systems are beginning to overlap and their boundaries are getting blurred. An era of continuous change in business models and management systems emerges: the search for competitive advantage (one over the other) becomes relentless, strenuous and resources depleting. Cooperation networks have to merge into larger entities, reducing competition and expanding collaboration. The search for collaborative advantage (for both jointly) will become the new mode of economic behavior.", "Engineering,_Manufacturing": 0.9945508838, "qwen": "Yes"}
{"id": "7175264", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=7175264", "title": "Shift kit", "text": "A shift kit is a set of components for automobiles designed to improve how well the car shifts between gears. Kits are made for both automatic and manual transmissions.\nGoals.\nShifts may be optimized for different goals. Some drivers want slow, smooth shifts for comfort, while others want quick shifts for performance or towing.\nTowing considerations.\nDuring a shift, power is lost in the clutch (for automatic transmissions the clutches are usually internal) due to clutch slip and the difference between the current and final output shaft speeds. This makes a quick shift more desirable when towing, to reduce clutch wear and heat developed in the transmission. Balancing this, too quick a shift increases peak mechanical loads on the transmission, engine and drive train; an instant shift would cause impact loads and lead to early mechanical failure, as well as an unpleasant driving experience.\nManual transmission kit.\nFor manual transmission equipped cars, it is a component that replaces the stock gear selector (shifter). A shift kit usually shortens the throws of selecting a gear (also known as a short throw shift or short shifter), therefore allowing a driver to reduce the shift time and change gears more efficiently.\nAutomatic transmission kit.\nAn automatic transmission's main focus is smooth shifting between gears. To accomplish this it often goes into two gears at once while shifting up, which is known as a shift overlap. In these cars, it is a kit that can reduce or eliminate the shift overlap. It will also reduce wear because the transmission won't be trying to drive in two gears at once.\nHistory.\nThe term \"Shift Kit\" is a registered trademark of the company \"TransGo\" which originated the development of automatic transmission valve body improvement and upgrade components such as springs, valves, and instructional materials to improve the shift characteristics and durability of automatic transmissions.", "Engineering,_Manufacturing": 0.9999964237, "qwen": "Yes"}
{"id": "25924075", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=25924075", "title": "Rake angle", "text": "In machining, the rake angle is a parameter used in various cutting processes, describing the angle of the cutting face relative to the workpiece. There are three types of rake angles: \"positive\", \"zero\" or \"neutral\", and \"negative\".\nPositive rake angles generally:\nNegative rake angles generally:\nZero rake angles:\nRecommended rake angles.\nRecommended rake angles can vary depending on the material being cut, tool material, depth of cut, cutting speed, machine, setup and process. This table summarizes recommended rake angles for: single-point turning on a lathe, drilling, milling, and sawing.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "48670353", "revid": "39455270", "url": "https://en.wikipedia.org/wiki?curid=48670353", "title": "Weihenstephan Standards", "text": "The Weihenstephan Standards (\"Weihenstephaner Standard\" in German), also referred to as \"WS\" in shorthand, are communication interfaces for machine data acquisition.\nThe standards were developed by a working group of machine manufacturers, plant suppliers, IT system vendors and technologists, under the guidance of the Technical University of Munich (TUM) at the Faculty of Food Packaging Technology in Weihenstephan, Germany.\nWeihenstephan libraries have been developed for production data acquisition in bottling and packaging plants (WS Pack), food industry plants (WS Food), in the bakery industry (WS Bake), and for processes within the brewing industry (WS Brew). These libraries are used to connect the plants industrial equipment within the production processes to higher-level management and control systems such as data acquisition systems (SCADA) or Manufacturing Execution Systems (MES). In the Weihenstephan Standards, the physical interface specification, specification of the interface content, recommendations for data evaluation and reporting are defined.\nThe Weihenstephan Standards 2000 comprise the guidelines for standard BDE specifications for bottling plants; the Weihenstephan Standards 2005 describe the interfaces and data provision for bottling and packaging plants in the beverage industry.\nDescription.\nThe Weihenstephan standards are located in the automation pyramid as a link between the production management level and the process control level. The standards allow an MES to exchange data with the controls of various machines and thus support the MES' operation. To help manage the data the standards provide:\nIn addition, industry-specific reports and evaluation examples are available in the Weihenstephan Standards.\nSee also.\nBrewmaxx", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "622558", "revid": "1001528092", "url": "https://en.wikipedia.org/wiki?curid=622558", "title": "Nibbler", "text": "A nibbler, or nibblers, is a tool for cutting sheet metal with minimal distortion. They may be used for nibbling. One type operates much like a punch and die, with a blade that moves in a linear fashion against a fixed die, removing small bits of metal and leaving a kerf approximately 6 mm wide. Another type operates similar to tin snips, but shears the sheet along two parallel tracks 3–6 mm apart, rolling up the waste in a tight spiral as it cuts. Nibblers may be manual (hand operated) or powered.\nPower nibblers are often powered by compressed air, though electrical types also exist. A common DIY nibbler tool is an electric drill attachment, which converts the rotary motion of the drill into a reciprocating motion of the jaw.", "Engineering,_Manufacturing": 0.9999914169, "qwen": "Yes"}
{"id": "625114", "revid": "1154927235", "url": "https://en.wikipedia.org/wiki?curid=625114", "title": "Forge welding", "text": "Forge welding (FOW), also called fire welding, is a solid-state welding process that joins two pieces of metal by heating them to a high temperature and then hammering them together. It may also consist of heating and forcing the metals together with presses or other means, creating enough pressure to cause plastic deformation at the weld surfaces. The process, although challenging, has been a method of joining metals used since ancient times and is a staple of traditional blacksmithing. Forge welding is versatile, being able to join a host of similar and dissimilar metals. With the invention of electrical welding and gas welding methods during the Industrial Revolution, manual forge-welding has been largely replaced, although automated forge-welding is a common manufacturing process.\nIntroduction.\nForge welding is a process of joining metals by heating them beyond a certain threshold and forcing them together with enough pressure to cause deformation of the weld surfaces, creating a metallic bond between the atoms of the metals. The pressure required varies, depending on the temperature, strength, and hardness of the alloy. Forge welding is the oldest welding technique, and has been used since ancient times. \nWelding processes can generally be grouped into two categories: fusion and diffusion welding. Fusion welding involves localized melting of the metals at the weld interfaces, and is common in electric or gas welding techniques. This requires temperatures much higher than the melting point of the metal in order to cause localized melting before the heat can thermally conduct away from the weld, and often a filler metal is used to keep the weld from segregating due to the high surface tension. Diffusion welding consists of joining the metals without melting them, welding the surfaces together while in the solid state.\nIn diffusion welding, the heat source is often lower than the melting point of the metal, allowing more even heat-distribution thus reducing thermal stresses at the weld. In this method a filler metal is typically not used, but the weld occurs directly between the metals at the weld interface. This includes methods such as cold welding, explosion welding, and forge welding. Unlike other diffusion methods, in forge welding the metals are heated to a high temperature before forcing them together, usually resulting in greater plasticity at the weld surfaces. This generally makes forge welding more versatile than cold-diffusion techniques, which are usually performed on soft metals like copper or aluminum.\nIn forge welding, the entire welding areas are heated evenly. Forge welding can be used for a much wider range of harder metals and alloys, like steel and titanium.\nHistory.\nThe history of joining metals goes back to the Bronze Age, where bronzes of different hardness were often joined by casting-in. This method consisted of placing a solid part into a molten metal contained in a mold and allowing it to solidify without actually melting both metals, such as the blade of a sword into a handle or the tang of an arrowhead into the tip. Brazing and soldering were also common during the Bronze Age. \nThe act of welding (joining two solid parts through diffusion) began with iron. The first welding process was forge welding, which started when humans learned to smelt iron from iron ore; most likely in Anatolia (Turkey) around 1800 BC. Ancient people could not create temperatures high enough to melt iron fully, so the bloomery process that was used for smelting iron produced a lump (bloom) of iron grains sintered together with small amounts of slag and other impurities, referred to as sponge iron because of its porosity. \nAfter smelting, the sponge iron needed to be heated above the welding temperature and hammered, or \"wrought.\" This squeezed out air pockets and melted slag, bringing the iron grains into close contact to form a solid block (billet). \nMany items made of wrought iron have been found by archeologists, that show evidence of forge welding, which date from before 1000 BC. Because iron was typically made in small amounts, any large object, such as the Delhi Pillar, needed to be forge welded out of smaller billets.\nForge welding grew from a trial-and-error method, becoming more refined over the centuries. Due to the poor quality of ancient metals, it was commonly employed in making composite steels, by joining high-carbon steels, that would resist deformation but break easily, with low-carbon steels, which resist fracture but bend too easily, creating an object with greater toughness and strength than could be produced with a single alloy. This method of pattern welding first appeared around 700 BC, and was primarily used for making weapons such as swords; the most widely known examples being Damascene, Japanese and Merovingian. This process was also common in the manufacture of tools, from wrought-iron plows with steel edges to iron chisels with steel cutting surfaces.\nMaterials.\nMany metals can be forge welded, with the most common being both high and low-carbon steels. Iron and even some hypoeutectic cast-irons can be forge welded. Some aluminum alloys can also be forge welded. Metals such as copper, bronze and brass do not forge weld readily. Although it is possible to forge weld copper-based alloys, it is often with great difficulty due to copper's tendency to absorb oxygen during the heating. Copper and its alloys are usually better joined with cold welding, explosion welding, or other pressure-welding techniques. With iron or steel, the presence of even small amounts of copper severely reduces the alloy's ability to forge weld.\nTitanium alloys are commonly forge welded. Because of titanium's tendency to absorb oxygen when molten, the solid-state, diffusion bond of a forge weld is often stronger than a fusion weld in which the metal is liquefied. \nForge welding between similar materials is caused by solid-state diffusion. This results in a weld that consists of only the welded materials without any fillers or bridging materials. Forge welding between dissimilar materials is caused by the formation of a lower melting temperature eutectic between the materials. Due to this the weld is often stronger than the individual metals.\nProcesses.\nThe most well-known and oldest forge-welding process is the manual-hammering method. Manual hammering is done by heating the metal to the proper temperature, coating with flux, overlapping the weld surfaces, and then striking the joint repeatedly with a hand-held hammer. The joint is often formed to allow space for the flux to flow out, by beveling or rounding the surfaces slightly, and hammered in a successively outward fashion to squeeze the flux out. The hammer blows are typically not as hard as those used for shaping, preventing the flux from being blasted out of the joint at the first blow.\nWhen mechanical hammers were developed, forge welding could be accomplished by heating the metal, and then placing it between the mechanized hammer and the anvil. Originally powered by waterwheels, modern mechanical-hammers can also be operated by compressed air, electricity, steam, gas engines, and many other ways. Another method is forge welding with a die, whereby the pieces of metal are heated and then forced into a die which both provides the pressure for the weld and keeps the joint at the finished shape. Roll welding is another forge welding process, where the heated metals are overlapped and passed through rollers at high pressures to create the weld. \nModern forge-welding is often automated, using computers, machines, and sophisticated hydraulic presses to produce a variety of products from a number of various alloys. For example, steel pipe is often forge-welded during the manufacturing process. Flat stock is heated and fed through specially-shaped rollers that both form the steel into a tube and simultaneously provide the pressure to weld the edges into a continuous seam. \nDiffusion bonding is a common method for forge welding titanium alloys in the aerospace industry. In this process the metal is heated while in a press or die. Beyond a specific critical-temperature, which varies depending on the alloy, the impurities burn out and the surfaces are forced together. \nOther methods include flash welding and percussion welding. These are resistance forge-welding techniques where the press or die is electrified, passing high current through the alloy to create the heat for the weld. Shielded active-gas forge-welding is a process of forge welding in an oxygen-reactive environment, to burn out oxides, using hydrogen gas and induction heating.\nTemperature.\nIron, different steels, and even cast-iron can be welded to each other, provided that their carbon content is close enough that the welding ranges overlap. Pure iron can be welded when nearly white hot; between and . Steel with a carbon content of 2.0% can be welded when orangish-yellow, between and . Common steel, between 0.2 and 0.8% carbon, is typically welded at a bright yellow heat.\nA primary requirement for forge welding is that both weld surfaces need to be heated to the same temperature and welded before they cool too much. When steel reaches the proper temperature, it begins to weld very readily, so a thin rod or nail heated to the same temperature will tend to stick at first contact, requiring it to be bent or twisted loose.\nCare must be taken to avoid overheating the metal to the point that it gives off sparks from rapid oxidation (burning), or else the weld will be poor and brittle.\nDecarburization.\nWhen steel is heated to an austenizing temperature, the carbon begins to diffuse through the iron. The higher the temperature; the greater the rate of diffusion. At such high temperatures, carbon readily combines with oxygen to form carbon dioxide, so the carbon can easily diffuse out of the steel and into the surrounding air. By the end of a blacksmithing job, the steel will be of a lower carbon content than it was prior to heating. Therefore, most blacksmithing operations are done as quickly as possible to reduce decarburization, preventing the steel from becoming too soft. \nTo produce the right amount of hardness in the finished product, the smith generally begins with steel that has a carbon content that is higher than desired. In ancient times, forging often began with steel that had a carbon content much too high for normal use. Most ancient forge-welding began with hypereutectoid steel, containing a carbon content sometimes well above 1.0%. Hypereutectoid steels are typically too brittle to be useful in a finished product, but by the end of forging the steel typically had a high carbon-content ranging from 0.8% (eutectoid tool-steel) to 0.5% (hypoeutectoid spring-steel).\nApplications.\nForge welding has been used throughout its history for making most any items out of steel and iron. It has been used in everything from the manufacture of tools, farming implements, and cookware to the manufacture of fences, gates, and prison cells. In the early Industrial Revolution, it was commonly used in the manufacture of boilers and pressure vessels, until the introduction of fusion-welding. It was commonly used through the Middle Ages for producing armor and weapons.\nOne of the most famous applications of forge welding involves the production of pattern-welded blades. During this process a smith repeatedly draws out a billet of steel, folds it back and welds it upon itself. Another application was the manufacture of shotgun barrels. Metal wire was spooled onto a mandrel, and then forged into a barrel that was thin, uniform, and strong. In some cases the forge-welded objects are acid-etched to expose the underlying pattern of metal, which is unique to each item and provides aesthetic appeal.\nDespite its diversity, forge welding had many limitations. A primary limitation was the size of objects that could be forge welded. Larger objects required a bigger heat source, and size reduced the ability to manually weld it together before it cooled too much. Welding large items like steel plate or girders was typically not possible, or at least highly impractical, until the invention of fusion welding, requiring them to be riveted instead. In some cases, fusion welding produced a much stronger weld, such as in the construction of boilers.\nFlux.\nForge welding requires the weld surfaces to be extremely clean or the metal will not join properly, if at all. Oxides tend to form on the surface while impurities like phosphorus and sulfur tend to migrate to the surface. Often a flux is used to keep the welding surfaces from oxidizing, which would produce a poor quality weld, and to extract other impurities from the metal. The flux mixes with the oxides that form and lowers the melting temperature and the viscosity of the oxides. This enables the oxides to flow out of the joint when the two pieces are beaten together. A simple flux can be made from borax, sometimes with the addition of powdered iron-filings.\nThe oldest flux used for forge welding was fine silica sand. The iron or steel would be heated in a reducing environment within the coals of the forge. Devoid of oxygen, the metal forms a layer of iron-oxide called wustite on its surface. When the metal is hot enough, but below the welding temperature, the smith sprinkles some sand onto the metal. The silicon in the sand reacts with the wustite to form fayalite, which melts just below the welding temperature. This produced a very effective flux which helped to make a strong weld.\nEarly examples of flux used different combinations and various amounts of iron fillings, borax, sal ammoniac, balsam of copaiba, cyanide of potash, and soda phosphate. The 1920 edition of \"Scientific American book of facts and formulae\" indicates a frequently offered trade secret as using copperas, saltpeter, common salt, black oxide of manganese, prussiate of potash, and \"nice welding sand\" (silicate). ", "Engineering,_Manufacturing": 0.9998594522, "qwen": "Yes"}
{"id": "75485", "revid": "842485", "url": "https://en.wikipedia.org/wiki?curid=75485", "title": "Electrical discharge machining", "text": "Electrical discharge machining (EDM), also known as spark machining, spark eroding, die sinking, wire burning or wire erosion, is a metal \nfabrication process whereby a desired shape is obtained by using electrical discharges (sparks). Material is removed from the work piece by a series of rapidly recurring current discharges between two electrodes, separated by a dielectric liquid and subject to an electric voltage. One of the electrodes is called the tool-electrode, or simply the or , while the other is called the workpiece-electrode, or . The process depends upon the tool and work piece not making physical contact.\nWhen the voltage between the two electrodes is increased, the intensity of the electric field in the volume between the electrodes becomes greater, causing dielectric break down of the liquid, and produces an electric arc. As a result, material is removed from the electrodes. Once the current stops (or is stopped, depending on the type of generator), new liquid dielectric is conveyed into the inter-electrode volume, enabling the solid particles (debris) to be carried away and the insulating properties of the dielectric to be restored. Adding new liquid dielectric in the inter-electrode volume is commonly referred to as . After a current flow, the voltage between the electrodes is restored to what it was before the breakdown, so that a new liquid dielectric breakdown can occur to repeat the cycle.\nHistory.\nThe erosive effect of electrical discharges was first noted in 1770 by English physicist Joseph Priestley.\nDie-sink EDM.\nTwo Soviet scientists, B. R. Lazarenko and N. I. Lazarenko, were tasked in 1943 to investigate ways of preventing the erosion of tungsten electrical contacts due to sparking. They failed in this task but found that the erosion was more precisely controlled if the electrodes were immersed in a dielectric fluid. This led them to invent an EDM machine used for working difficult-to-machine materials such as tungsten. The Lazarenkos' machine is known as an R-C-type machine, after the resistor–capacitor circuit (RC circuit) used to charge the electrodes.\nSimultaneously but independently, an American team, Harold Stark, Victor Harding, and Jack Beaver, developed an EDM machine for removing broken drills and taps from aluminium castings. Initially constructing their machines from under-powered electric-etching tools, they were not very successful. But more powerful sparking units, combined with automatic spark repetition and fluid replacement with an electromagnetic interrupter arrangement produced practical machines. Stark, Harding, and Beaver's machines were able to produce 60 sparks per second. Later machines based on their design used vacuum tube circuits that were able to produce thousands of sparks per second, significantly increasing the speed of cutting.\nWire-cut EDM.\nThe wire-cut type of machine arose in the 1960s for making tools (dies) from hardened steel. The tool electrode in wire EDM is simply a wire. To avoid the erosion of the wire causing it to break, the wire is wound between two spools so that the active part of the wire is constantly changing. The earliest numerical controlled (NC) machines were conversions of punched-tape vertical milling machines. The first commercially available NC machine built as a wire-cut EDM machine was manufactured in the USSR in 1967. Machines that could optically follow lines on a master drawing were developed by David H. Dulebohn's group in the 1960s at Andrew Engineering Company for milling and grinding machines. Master drawings were later produced by computer numerical controlled (CNC) plotters for greater accuracy. A wire-cut EDM machine using the CNC drawing plotter and optical line follower techniques was produced in 1974. Dulebohn later used the same plotter CNC program to directly control the EDM machine, and the first CNC EDM machine was produced in 1976.\nCommercial wire EDM capability and use has advanced substantially during recent decades. Feed rates have increased and surface finish can be finely controlled.\nGeneralities.\nElectrical discharge machining is a machining method primarily used for hard metals or those that would be very difficult to machine with traditional techniques. EDM typically works with materials that are electrically conductive, although methods have also been proposed for using EDM to machine insulating ceramics. EDM can cut intricate contours or cavities in pre-hardened steel without the need for heat treatment to soften and re-harden them. This method can be used with any other metal or metal alloy such as titanium, hastelloy, kovar, and inconel. Also, applications of this process to shape polycrystalline diamond tools have been reported.\nEDM is often included in the \"non-traditional\" or \"non-conventional\" group of machining methods together with processes such as electrochemical machining (ECM), water jet cutting (WJ, AWJ), laser cutting and opposite to the \"conventional\" group (turning, milling, grinding, drilling and any other process whose material removal mechanism is essentially based on mechanical forces).\nIdeally, EDM can be seen as a series of breakdown and restoration of the liquid dielectric in-between the electrodes. However, caution should be exerted in considering such a statement because it is an idealized model of the process, introduced to describe the fundamental ideas underlying the process. Yet, any practical application involves many aspects that may also need to be considered. For instance, the removal of the debris from the inter-electrode volume is likely to be always partial. Thus the electrical properties of the dielectric in the inter-electrodes volume can be different from their nominal values and can even vary with time. The inter-electrode distance, often also referred to as spark-gap, is the result of the control algorithms of the specific machine used. The control of such a distance appears logically to be central to this process. Also, not all of the current between the dielectric is of the ideal type described above: the spark-gap can be short-circuited by the debris. The control system of the electrode may fail to react quickly enough to prevent the two electrodes (tool and workpiece) from coming into contact, with a consequent short circuit. This is unwanted because a short circuit contributes to material removal differently from the ideal case. The flushing action can be inadequate to restore the insulating properties of the dielectric so that the current always happens in the point of the inter-electrode volume (this is referred to as arcing), with a consequent unwanted change of shape (damage) of the tool-electrode and workpiece. Ultimately, a description of this process in a suitable way for the specific purpose at hand is what makes the EDM area such a rich field for further investigation and research.\nTo obtain a specific geometry, the EDM tool is guided along the desired path very close to the work; ideally it should not touch the workpiece, although in reality this may happen due to the performance of the specific motion control in use. In this way, a large number of current discharges (colloquially also called sparks) happen, each contributing to the removal of material from both tool and workpiece, where small craters are formed. The size of the craters is a function of the technological parameters set for the specific job at hand. They can be with typical dimensions ranging from the nanoscale (in micro-EDM operations) to some hundreds of micrometers in roughing conditions.\nThe presence of these small craters on the tool results in the gradual erosion of the electrode. This erosion of the tool-electrode is also referred to as wear. Strategies are needed to counteract the detrimental effect of the wear on the geometry of the workpiece. One possibility is that of continuously replacing the tool-electrode during a machining operation. This is what happens if a continuously replaced wire is used as electrode. In this case, the correspondent EDM process is also called wire EDM. The tool-electrode can also be used in such a way that only a small portion of it is actually engaged in the machining process and this portion is changed on a regular basis. This is, for instance, the case when using a rotating disk as a tool-electrode. The corresponding process is often also referred to as EDM grinding.\nA further strategy consists in using a set of electrodes with different sizes and shapes during the same EDM operation. This is often referred to as multiple electrode strategy, and is most common when the tool electrode replicates in negative the wanted shape and is advanced towards the blank along a single direction, usually the vertical direction (i.e. z-axis). This resembles the sink of the tool into the dielectric liquid in which the workpiece is immersed, so, not surprisingly, it is often referred to as die-sinking EDM (also called conventional EDM and ram EDM). The corresponding machines are often called sinker EDM. Usually, the electrodes of this type have quite complex forms. If the final geometry is obtained using a usually simple-shaped electrode which is moved along several directions and is possibly also subject to rotations, often the term EDM milling is used.\nIn any case, the severity of the wear is strictly dependent on the technological parameters used in the operation (for instance: polarity, maximum current, open circuit voltage). For example, in micro-EDM, also known as μ-EDM, these parameters are usually set at values which generates severe wear. Therefore, wear is a major problem in that area.\nThe problem of wear to graphite electrodes is being addressed. In one approach, a digital generator, controllable within milliseconds, reverses polarity as electro-erosion takes place. That produces an effect similar to electroplating that continuously deposits the eroded graphite back on the electrode. In another method, a so-called \"Zero Wear\" circuit reduces how often the discharge starts and stops, keeping it on for as long a time as possible.\nDefinition of the technological parameters.\nDifficulties have been encountered in the definition of the technological parameters that drive the process.\nTwo broad categories of generators, also known as power supplies, are in use on EDM machines commercially available: the group based on RC circuits and the group based on transistor controlled pulses.\nIn both categories, the primary parameters at setup are the current and frequency delivered. In RC circuits, however, little control is expected over the time duration of the discharge, which is likely to depend on the actual spark-gap conditions (size and pollution) at the moment of the discharge. Also, the open circuit voltage (i.e. the voltage between the electrodes when the dielectric is not yet broken) can be identified as steady state voltage of the RC circuit.\nIn generators based on transistor control, the user is usually able to deliver a train of pulses of voltage to the electrodes. Each pulse can be controlled in shape, for instance, quasi-rectangular. In particular, the time between two consecutive pulses and the duration of each pulse can be set. The amplitude of each pulse constitutes the open circuit voltage. Thus, the maximum duration of discharge is equal to the duration of a pulse of voltage in the train. Two pulses of current are then expected not to occur for a duration equal or larger than the time interval between two consecutive pulses of voltage.\nThe maximum current during a discharge that the generator delivers can also be controlled. Because other sorts of generators may also be used by different machine builders, the parameters that may actually be set on a particular machine will depend on the generator manufacturer. The details of the generators and control systems on their machines are not always easily available to their user. This is a barrier to describing unequivocally the technological parameters of the EDM process. Moreover, the parameters affecting the phenomena occurring between tool and electrode are also related to the controller of the motion of the electrodes.\nA framework to define and measure the electrical parameters during an EDM operation directly on inter-electrode volume with an oscilloscope external to the machine has been recently proposed by Ferri \"et al.\" These authors conducted their research in the field of μ-EDM, but the same approach can be used in any EDM operation. This would enable the user to estimate directly the electrical parameters that affect their operations without relying upon machine manufacturer's claims. When machining different materials in the same setup conditions, the actual electrical parameters of the process are significantly different.\nMaterial removal mechanism.\nThe first serious attempt at providing a physical explanation of the material removal during electric discharge machining is perhaps that of Van Dijck. Van Dijck presented a thermal model together with a computational simulation to explain the phenomena between the electrodes during electric discharge machining. However, as Van Dijck himself admitted in his study, the number of assumptions made to overcome the lack of experimental data at that time was quite significant.\nFurther models of what occurs during electric discharge machining in terms of heat transfer were developed in the late eighties and early nineties. It resulted in three scholarly papers: the first presenting a thermal model of material removal on the cathode, the second presenting a thermal model for the erosion occurring on the anode and the third introducing a model describing the plasma channel formed during the passage of the discharge current through the dielectric liquid. Validation of these models is supported by experimental data provided by AGIE.\nThese models give the most authoritative support for the claim that EDM is a thermal process, removing material from the two electrodes because of melting or vaporization, along with pressure dynamics established in the spark-gap by the collapsing of the plasma channel. However, for small discharge energies the models are inadequate to explain the experimental data. All these models hinge on a number of assumptions from such disparate research areas as submarine explosions, discharges in gases, and failure of transformers, so it is not surprising that alternative models have been proposed more recently in the literature trying to explain the EDM process.\nAmong these, the model from Singh and Ghosh reconnects the removal of material from the electrode to the presence of an electrical force on the surface of the electrode that could mechanically remove material and create the craters. This would be possible because the material on the surface has altered mechanical properties due to an increased temperature caused by the passage of electric current. The authors' simulations showed how they might explain EDM better than a thermal model (melting or evaporation), especially for small discharge energies, which are typically used in μ-EDM and in finishing operations.\nGiven the many available models, it appears that the material removal mechanism in EDM is not yet well understood and that further investigation is necessary to clarify it, especially considering the lack of experimental scientific evidence to build and validate the current EDM models. This explains an increased current research effort in related experimental techniques.\nIn this conclusion, there are following major factors are achieved during machining operations:\nTypes.\nSinker EDM.\nSinker EDM, also called ram EDM, cavity type EDM or volume EDM, consists of an electrode and workpiece submerged in an insulating liquid such as, more typically, oil or, less frequently, other dielectric fluids. The electrode and workpiece are connected to a suitable power supply. The power supply generates an electrical potential between the two parts. As the electrode approaches the workpiece, dielectric breakdown occurs in the fluid, forming a plasma channel, and a small spark jumps.\nThese sparks usually strike one at a time, because it is very unlikely that different locations in the inter-electrode space have the identical local electrical characteristics which would enable a spark to occur simultaneously in all such locations. These sparks happen in huge numbers at seemingly random locations between the electrode and the workpiece. As the base metal is eroded, and the spark gap subsequently increased, the electrode is lowered automatically by the machine so that the process can continue uninterrupted. Several hundred thousand sparks occur per second, with the actual duty cycle carefully controlled by the setup parameters. These controlling cycles are sometimes known as \"on time\" and \"off time\", which are more formally defined in the literature.\nThe on time setting determines the length or duration of the spark. Hence, a longer on time produces a deeper cavity from each spark, creating a rougher finish on the workpiece. The reverse is true for a shorter on time. Off time is the period of time between sparks. Although not directly affecting the machining of the part, the off time allows the flushing of dielectric fluid through a nozzle to clean out the eroded debris. Insufficient debris removal can cause repeated strikes in the same location which can lead to a short circuit. Modern controllers monitor the characteristics of the arcs and can alter parameters in microseconds to compensate. The typical part geometry is a complex 3D shape, often with small or odd shaped angles. Vertical, orbital, vectorial, directional, helical, conical, rotational, spin and indexing machining cycles are also used.\nWire EDM.\nIn \"wire electrical discharge machining\" (WEDM), also known as \"wire-cut EDM\" and \"wire cutting\", a thin single-strand metal wire, usually brass, is fed through the workpiece, submerged in a tank of dielectric fluid, typically deionized water. Wire-cut EDM is typically used to cut plates as thick as 300mm and to make punches, tools, and dies from hard metals that are difficult to machine with other methods. \nThe wire, which is constantly fed from a spool, is held between upper and lower diamond guides which is centered in a water nozzle head. The guides, usually CNC-controlled, move in the \"x\"–\"y\" plane. On most machines, the upper guide can also move independently in the \"z\"–\"u\"–\"v\" axis, giving rise to the ability to cut tapered and transitioning shapes (circle on the bottom, square at the top for example). The upper guide can control axis movements in the GCode standard, \"x\"–\"y\"–\"u\"–\"v\"–\"i\"–\"j\"–\"k\"–\"l\"–. This allows the wire-cut EDM to be programmed to cut very intricate and delicate shapes. \nThe upper and lower diamond guides are usually accurate to , and can have a cutting path or \"kerf\" as small as using Ø wire, though the average cutting kerf that achieves the best economic cost and machining time is using Ø brass wire. The reason that the cutting width is greater than the width of the wire is because sparking occurs from the sides of the wire to the work piece, causing erosion. This \"overcut\" is necessary, for many applications it is adequately predictable and therefore can be compensated for (for instance in micro-EDM this is not often the case). Spools of wire are long — an 8 kg spool of 0.25 mm wire is just over 19 kilometers in length. Wire diameter can be as small as and the geometry precision is not far from ± . \nThe wire-cut process uses water as its dielectric fluid, controlling its resistivity and other electrical properties with filters and PID controlled de-ionizer units. The water flushes the cut debris away from the cutting zone. Flushing is an important factor in determining the maximum feed rate for a given material thickness.\nAlong with tighter tolerances, multi axis EDM wire-cutting machining centers have added features such as multi heads for cutting two parts at the same time, controls for preventing wire breakage, automatic self-threading features in case of wire breakage, and programmable machining strategies to optimize the operation.\nWire-cutting EDM is commonly used when low residual stresses are desired, because it does not require high cutting forces for removal of material. If the energy/power per pulse is relatively low (as in finishing operations), little change in the mechanical properties of a material is expected due to these low residual stresses, although material that hasn't been stress-relieved can distort in the machining process.\nThe work piece may undergo a significant thermal cycle, its severity depending on the technological parameters used. Such thermal cycles may cause formation of a recast layer on the part and residual tensile stresses on the work piece. If machining takes place after heat treatment, dimensional accuracy will not be affected by heat treat distortion.\nFast hole drilling EDM.\nFast hole drilling EDM was designed for producing fast, accurate, small, and deep holes. It is conceptually akin to sinker EDM but the electrode is a rotating tube conveying a pressurized jet of dielectric fluid. It can make a hole an inch deep in about a minute and is a good way to machine holes in materials too hard for twist-drill machining. This EDM drilling type is used largely in the aerospace industry, producing cooling holes into aero blades and other components. It is also used to drill holes in industrial gas turbine blades, in molds and dies, and in bearings.\nApplications.\nPrototype production.\nThe EDM process is most widely used by the mold-making, tool, and die industries, but is becoming a common method of making prototype and production parts, especially in the aerospace, automobile and electronics industries in which production quantities are relatively low. In sinker EDM, a graphite, copper tungsten, or pure copper electrode is machined into the desired (negative) shape and fed into the workpiece on the end of a vertical ram.\nCoinage die making.\nFor the creation of dies for producing jewelry and badges, or blanking and piercing (through use of a pancake die) by the coinage (stamping) process, the positive master may be made from sterling silver, since (with appropriate machine settings) the master is significantly eroded and is used only once. The resultant negative die is then hardened and used in a drop hammer to produce stamped flats from cutout sheet blanks of bronze, silver, or low proof gold alloy. For badges these flats may be further shaped to a curved surface by another die. This type of EDM is usually performed submerged in an oil-based dielectric. The finished object may be further refined by hard (glass) or soft (paint) enameling, or electroplated with pure gold or nickel. Softer materials such as silver may be hand engraved as a refinement.\nSmall hole drilling.\nSmall hole drilling EDM is used in a variety of applications.\nOn wire-cut EDM machines, small hole drilling EDM is used to make a through hole in a workpiece through which to thread the wire for the wire-cut EDM operation. A separate EDM head specifically for small hole drilling is mounted on a wire-cut machine and allows large hardened plates to have finished parts eroded from them as needed and without pre-drilling.\nSmall hole EDM is used to drill rows of holes into the leading and trailing edges of turbine blades used in jet engines. Gas flow through these small holes allows the engines to use higher temperatures than otherwise possible. The high-temperature, very hard, single crystal alloys employed in these blades makes conventional machining of these holes with high aspect ratio extremely difficult, if not impossible.\nSmall hole EDM is also used to create microscopic orifices for fuel system components, spinnerets for synthetic fibers such as rayon, and other applications.\nThere are also stand-alone small hole drilling EDM machines with an \"x\"–\"y\" axis also known as a super drill or \"hole popper\" that can machine blind or through holes. EDM drills bore holes with a long brass or copper tube electrode that rotates in a chuck with a constant flow of distilled or deionized water flowing through the electrode as a flushing agent and dielectric. The electrode tubes operate like the wire in wire-cut EDM machines, having a spark gap and wear rate. Some small-hole drilling EDMs are able to drill through 100 mm of soft or hardened steel in less than 10 seconds, averaging 50% to 80% wear rate. Holes of 0.3 mm to 6.1 mm can be achieved in this drilling operation. Brass electrodes are easier to machine but are not recommended for wire-cut operations due to eroded brass particles causing \"brass on brass\" wire breakage, therefore copper is recommended.\nMetal disintegration machining.\nSeveral manufacturers produce EDM machines for the specific purpose of removing broken cutting tools and fasteners from work pieces. In this application, the process is termed \"metal disintegration machining\" or MDM. The metal disintegration process removes only the center of the broken tool or fastener, leaving the hole intact and allowing a part to be reclaimed.\nClosed loop manufacturing.\nClosed loop manufacturing can improve the accuracy and reduce the tool costs\nAdvantages and disadvantages.\nEDM is often compared to Electrochemical Machining.\nAdvantages of EDM include:\nDisadvantages of EDM include:", "Engineering,_Manufacturing": 0.9999694824, "qwen": "Yes"}
{"id": "22293052", "revid": "28903366", "url": "https://en.wikipedia.org/wiki?curid=22293052", "title": "Four-slide", "text": "A four-slide, also known as a multislide, multi-slide, or four-way, is a metalworking machine tool used in the high-volume manufacture of small stamped components from bar or wire stock. The press is most simply described as a horizontal stamping press that uses cams to control tools. The machine is used for progressive or transfer stamping operations.\nDesign.\nA four-slide is quite different from most other presses. The key of the machine is its moving slides that have tools attached, which strike the workpiece together or in sequence to form it. These slides are driven by four shafts that outline the machine. The shafts are connected by bevel gears so that one shaft is driven by an electric motor, and then that shaft's motion drives the other three shafts. Each shaft then has cams which drive the slides, usually of a split-type. This shafting arrangement allows the workpiece to be worked for four sides, which makes this machine extremely versatile. A hole near the center of the machine is provided to expel the completed workpiece.\nAdvantages and disadvantages.\nThe greatest advantage of the four-slide machine is its ability to complete all of the operations required to form the workpiece from start to finish. Moreover, it can handle certain parts that transfer or progressive dies cannot, because it can manipulate from four axes. Due to this flexibility it reduces the cost of the finished part because it requires less machines, setups, and handling. Also, because only one machine is required, less space is required for any given workpiece. As compared to standard stamping presses the tooling is usually inexpensive, due to the simplicity of the tools. A four-slide can usually produce 20,000 to 70,000 finished parts per 16-hour shift, depending on the number of operations per part; this speed usually results in a lower cost per part.\nThe biggest disadvantage is its size constraints. The largest machines can handle stock up to wide, long, and thick. For wires the limit is . Other limits are the travel on the slides, which maxes out at , and the throw of the forming cams, which is between . The machine is also limited to only shearing and bending operations. Extrusion and upsetting operations are impractical because it hinders the movement of the workpiece to the next station. Drawing and stretching require too much tonnage and the mechanisms required for the operations are space prohibitive. Finally, this machine is only feasible to use on high volume parts because of the long lead time required to set up the tooling.\nMaterials.\nThe material stock used in four-slides is usually limited by its formability and not the machine capabilities. Usually the forming characteristics and bending radii are the most limiting factors. The most commonly used materials are:\nUse.\nItems that are commonly produced on this machine include: automotive stampings, hinges, links, clips, and razor blades.", "Engineering,_Manufacturing": 1.0000059605, "qwen": "Yes"}
{"id": "22302175", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=22302175", "title": "Integration platform", "text": "An integration platform is software which integrates different applications and services. It differentiates itself from the enterprise application integration which has a focus on supply chain management. It uses the idea of system integration to create an environment for engineers.\nIntegration platforms can be built from components, purchased as a pre-built product ready for installation or procured from an integration Platform as a Service (iPaaS) company.\nOverview.\nAn integration platform tries to create an environment in which engineers can:\nCommon components of integration platform.\nIntegration platform typically contains a set of functional components, such as\nDifferentiation.\nAn integration platform has a focus to be designed by and helpful to engineers. It has no intention to map business processes or integrate tools for supply chain management. Therefore it is not related to those systems.", "Engineering,_Manufacturing": 0.9975619912, "qwen": "Yes"}
{"id": "22316878", "revid": "6225634", "url": "https://en.wikipedia.org/wiki?curid=22316878", "title": "Horizontal boring machine", "text": "A horizontal boring machine or horizontal boring mill is a machine tool which bores holes in a horizontal direction. There are three main types — table, planer and floor. The table type is the most common and, as it is the most versatile, it is also known as the universal type.\nA horizontal boring machine has its work spindle parallel to the ground and work table. Typically there are three linear axes in which the tool head and part move. Convention dictates that the main axis that drives the part towards the work spindle is the Z axis, with a cross-traversing X axis and a vertically traversing Y axis. The work spindle is referred to as the C axis and, if a rotary table is incorporated, its centre line is the B axis. \nHorizontal boring machines are often heavy-duty industrial machines used for roughing out large components, but there are high-precision models too. Modern machines use advanced computer numerical control (CNC) systems and techniques. Charles DeVlieg entered the Machine Tool Hall of Fame for his work upon a highly precise model, which he called a JIGMIL. The accuracy of this machine convinced the United States Air Force to accept John Parson's idea for numerically controlled machine tools.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "41927384", "revid": "1574590", "url": "https://en.wikipedia.org/wiki?curid=41927384", "title": "Siliconware Precision Industries", "text": "Siliconware Precision Industries (NASDAQ:SPIL) was set up on May 17, 1984 and now is based in Taichung, Taiwan. The company focuses on semiconductor packaging and testing services for PC, communications, consumer integrated circuits markets. These services are provided to protect semiconductor chips, better integrating into electronic systems, and improving the dissipation of heat.\nHistory.\nSiliconware Precision Industries as founded in 1984. In 2000 the company became a public company in NASDAQ and in the same year, SPIL merged with Siliconware Corporation. The company acquired the common shares of ChipMOS Technologies LTD. in 2007, Taiwan Occupational Safety and Health Management in 2008, and merged with Siliconware Investment Company Ltd. in the next year of 2009.\nIn 2013, the company and Siliconware USA, Inc. settled the long patent infringement litigation with Tessera Technologies, Inc. Siliconware would pay Tessera, Inc. a partial upfront fee and smaller quarterly payments over the next five years, for being released from the litigation.\nProducts and services.\nThe packaging materials the company processed include substrate (ball grid array) and lead-frame packages, the testing services provided by the company are based on logic, mixed-signal, and embedded memory devices to measure the performance and reliability of packaged semiconductor devices. In addition, the company also provides turnkey service, shipment service, and other related services, such as wafer probing, tape and reel services.\nProducts of the company are under ISO 9001 certification, QS 9000 certification, ISO 14001 EMS International Certification, TS16949 certification, OHSAS 18001 Certification, IECQ HSPM certification, ISO 14064-1 verification, PAS 2050 verification.\nThe company competes with Advanced Semiconductor Engineering, Inc., Amkor Technology Inc., and STATS ChipPAC Ltd.", "Engineering,_Manufacturing": 0.9996109605, "qwen": "Yes"}
{"id": "41938141", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=41938141", "title": "Aluminum polymer composite", "text": "An aluminum polymer composite (APC) material combines aluminum with a polymer to create materials with interesting characteristics. In 2014 researchers used a 3d laser printer to produce a polymer matrix. When coated with a 50-100 nanometer layer of aluminum oxide, the material was able to withstand loads of as much as 280 megapascals, stronger than any other known material whose density was less than , that of water.\nAluminum foam.\nSpherical aluminum foam pieces bonded by polymers produced foams that were 80-95% metal. Such foams were test=manufactured on an automated assembly line and are under consideration as automobile parts.\nThermal conductivity.\nExperimentally determined thermal conductivity of specific APCs matched both the Agari and Bruggeman models provide a good estimation for thermal conductivity. The experimental values of both thermal conductivity and diffusivity have shown a better heat transport for the composite filled with large particles.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "39228560", "revid": "8766034", "url": "https://en.wikipedia.org/wiki?curid=39228560", "title": "Moving magnet actuator", "text": "A moving magnet actuator is a type of electromagnetic linear actuator. It typically consists of an arrangement of a mobile permanent magnet and fixed coil, arranged so that currents in the coil generate a pair of equal and opposite forces between the coil and magnet. \nA voice coil actuator, also called a voice coil motor (VCM), is an electromagnetic linear actuator where the magnet is fixed and the coil is mobile. In this configuration the coil is common called a voice coil. ", "Engineering,_Manufacturing": 0.9999320507, "qwen": "Yes"}
{"id": "45486879", "revid": "12396222", "url": "https://en.wikipedia.org/wiki?curid=45486879", "title": "Rapid Heat Cycle Molding", "text": "Rapid Heat Cycle Molding (RHCM) is also known as steam injection molding. Dr. Chao-Tsai Huang has written an extensive 68 page paper outlining, among other things, a case study on RHCM. His paper is entitled In-depth Study of RHCM and IHM Technologiesand Industrial Applications.\nIn general, ABS material is used as the raw material. The primary advantage of steam injection is that it eliminates weld-lines on molded parts. This allows companies to eliminate future processes such as painting. In non-steam molding, water will heat the tool to a constant temperature. Plastic will be injected to the warm tool.\nIn steam molding, steam is injected at 160 degrees to heat the tool. When the tool reaches a predetermined temperature (about 140 degrees), the plastic is injected. Cold water is immediately added to the process to cool the plastic down to around 40 degrees.\nBecause the mold is so hot when the plastic is injected, there are no weld lines, and a \"perfect\" product results. Steam injection molding is now being extensively used to produce the front covers of LCD TVs.", "Engineering,_Manufacturing": 0.9921782613, "qwen": "Yes"}
{"id": "2748600", "revid": "36932059", "url": "https://en.wikipedia.org/wiki?curid=2748600", "title": "Laser engineered net shaping", "text": "Laser powder forming, also known by the proprietary name (laser engineered net shaping) is an additive manufacturing technology developed for fabricating metal parts directly from a computer-aided design (CAD) solid model by using a metal powder injected into a molten pool created by a focused, high-powered laser beam. This technique is also equivalent to several trademarked techniques that have the monikers direct metal deposition (DMD), and laser consolidation (LC). Compared to processes that use powder beds, such as selective laser melting (SLM) objects created with this technology can be substantially larger, even up to several feet long.\nMethod.\nA high power laser is used to melt metal powder supplied coaxially to the focus of the laser beam through a deposition head. The laser beam typically travels through the center of the head and is focused to a small spot by one or more lenses. The X-Y table is moved in raster fashion to fabricate each layer of the object. The head is moved up vertically after each layer is completed. \nMetal powders are delivered and distributed around the circumference of the head either by gravity, or by using a pressurized carrier gas. An inert shroud gas is often used to shield the melt pool from atmospheric oxygen for better control of properties, and to promote layer to layer adhesion by providing better surface wetting.\nOther techniques.\nThis process is similar to other 3D fabrication technologies in its approach in that it forms a solid component by the layer additive method. The LENS process can go from metal and metal oxide powder to metal parts, in many cases without any secondary operations. LENS is similar to selective laser sintering, but the metal powder is applied only where material is being added to the part at that moment. It can produce parts in a wide range of alloys, including titanium, stainless steel, aluminum, and other specialty materials; as well as composite and functionally graded materials. Primary applications for LENS technology include repair and overhaul, rapid prototyping, rapid manufacturing, and limited-run manufacturing for aerospace, defense, and medical markets. Microscopy studies show the LENS parts to be fully dense with no compositional degradation. Mechanical testing reveals outstanding as-fabricated mechanical properties.\nThe process can also make \"near\" net shape parts when it is not possible to make an item to exact specifications. In these cases post production process like light machining, surface finishing, or heat treatment may be applied to achieve end compliance. It is used as finishing operations.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "31076991", "revid": "26021349", "url": "https://en.wikipedia.org/wiki?curid=31076991", "title": "StreetStrider", "text": "StreetStrider is the brand name for a mobile elliptical trainer. The StreetStrider consists of a T-shaped lower frame to which two front wheels and a rear wheel containing a drive assembly are attached, and an upright frame to which two reciprocating arm levers are attached. Two elongated foot platforms on either side of the lower frame are attached to cranks as part of the drive assembly, which, as with bicycle drivetrain systems, also includes a hub, a rotating axle, and an internal hub gear system translating the axle rotation to the hub. The StreetStrider drive assembly is either chained or chainless direct drive, depending on model. The lower end of each arm lever is attached to the front end of each foot platform, which, by connection in the rear to the rotating crank arm and in the front to the pivoting arm lever, moves generally in an elliptical path. The device also includes a leaning mechanism for steering, as well as brakes and multiple gearing. It was developed by David W. Kraus, who wrote the patent for the device.\nThe StreetStrider duplicates the motion of a stationary elliptical trainer in a mobile device. The rider achieves a full-body weight-bearing low-impact high-cardiovascular workout while moving outdoors. With a branded trainer stand, adult StreetStrider models can be fashioned into stationary elliptical trainers, enabling indoor use during inclement weather. The StreetStrider can be used for physical fitness, weight loss, physical therapy, human-powered transport, and outdoor adventure.", "Engineering,_Manufacturing": 0.9965624809, "qwen": "Yes"}
{"id": "65923399", "revid": "36529075", "url": "https://en.wikipedia.org/wiki?curid=65923399", "title": "Tandem rolling mill", "text": "A tandem rolling mill is a rolling mill with two or more close-coupled stands, where the reduction is achieved by the inter-stand tension(s) and the compressive force between the work rolls.\nFor mills rolling thinner strip, bridles may be added either at the entry and/or the exit to increase the strip tension near the adjacent stands further increasing their reduction capability.\nIntroduction.\nThe first mention of a tandem rolling mill is Richard Ford's 1766 English patent for the hot rolling of wire.\nIn 1798 he received another patent, this time for the hot rolling of plates and sheets using a tandem mill.\nThe main advantages of a tandem mill are:\nOne disadvantage of a tandem mill is the high capital cost compared to that of a single stand reversing mill.\nThe need for tandem rolling mills, and rolling mills in general, is being reduced by the use of continuous casters.\nThe development of transfer bar casting, also called thin slab casting meant that slab roughing mills were no-longer required.\nThin strip casting with a thickness of 2 mm has bypassed the tandem hot mill; and further reduction in the casting thickness to produce strip steel the same as annealed cold rolled strip will bypass the tandem cold mill and the annealing process.\nEach stand of a tandem mill is set up for rolling using the mill-stand's spring curve and the compressive curve of the metal so that both the rolling force and the exit thickness of each stand are determined.\nThis article describes the characteristics of a mill stand, the properties of a metal (especially steel), and the control of a tandem mill using both equations and diagrams.\nMill stand characteristics.\nThe mill stand spring curve is obtained by pressing the work rolls together with increasing force. This causes the work rolls to bend, the screw-downs to compress and the mill housings to stretch.\nTo reduce work roll bending, a much larger roll is positioned above the top work roll and another is placed below the bottom work roll. This arrangement is called a 4-high mill, as shown in sketch 1.\nThe red line in graph 1 is the linear approximation \nor conversely, the screw-down position\nwhere is called the mill modulus and is the slope of the spring curve in the area of the datum point . For most mills is approximately 4 MN/mm. Larger values would require much thicker mill housings and screw-downs.\nA datum is performed by lowering the screws below face until the measured force equals the required datum force , at which point the screw-down position is set so that it equals the datum screw position . At BlueScope Steel's No. 2 temper mill the datum point was 5 mm at a force of 7 MN.\nWood and Ivacheff\nanalysed the information obtained when measuring the mill modulus by pressing the work rolls together until a typical rolling force was reached, and then they continued to measure the force and screw-down position as the rolls were lifted. The shape of the plotted figures (overlaid, looped, or a figure eight) was found to give good indication of the mill stand's condition.\nThe datum point is chosen so that the screw-down position is never negative. This was necessary with the control computers of the 1960s, such as the GE/PAC 4020 installed at the then Australian Iron & Steel (now BlueScope) Port Kembla plate mill, which used an assembler language that did not like negative numbers.\nAlso, a datum point is used rather than trying to measure the point at which the force just becomes zero.\nThe exact equation used to calculate the required screw-down setting for a required force is:\nwhere: is the value to best suit the measured values and is an adapter which corrects for the thermal expansion of the mill housing and rolls as they warm up during rolling. It is set to zero after a work roll change, when the datum is performed with the new rolls at room temperature.\nUsing the measured values of and during the rolling of one piece of metal, allows the adaptor to be calculated for use at the start of the next piece.\nRoll force measurement.\nLoad cells are used to measure the force exerted onto the work rolls by the product.\nTo obtain the true roll force acting on the work rolls the position of the load cells is important; are they with the filler plates under the bottom backup-roll bearings, or on top of the top backup-roll bearings. Both positions are shown in sketch 2.\nAnother thing that must be considered (if they are present) is the roll balance cylinders.\nThe roll balance cylinders act to separate the work rolls (no force between them) when the screw-downs are raised; that is, the force of the balance cylinders is just greater than the weight of the top roll set, .\nThe above roll weights and are only nominal values; the actual values will vary a little depending on how many times the rolls have been ground down between campaigns.\nSince the roll weights are only nominal values, any residual error is slowly zeroed out whenever the roll balance is on and the screws are raised sufficiently.\nSteel characteristics.\nA useful formula for the compression curve of steel is:\nwhere\n moves the curve vertically, i.e. it sets the initial yield stress;\n changes the slope, i.e. the metal's work hardening rate.\nThe initial steep section in graph 2 is elastic compression. The effective height of this is reduced by the entry and exit tensions when present, as in a tandem mill. Notice that the curve becomes steeper as the thickness approaches zero, i.e. it would take infinite force to make the steel infinitely thin.\nThe slope of the plastic region around the operating point is normally represented by the letter .\nMathematical modelling.\nFor a rolling mill to operate, the work roll gap is set prior to the product entering the mill. Originally this setting was empirical; that is, set by the operators according to their experiences of that product's initial dimensions and the required finished thickness.\nWith a reversing mill, the profile of intermediate thicknesses was also empirical. To obtain greater consistency, attempts were made to characterize the rolling process. In 1948, Bland and Ford\n were one of the first to publish such a mathematical model.\nEssentially such mathematical models represent the mill (its spring curve) and the compressive behavior of the product to calculate the mill's \"setup\".\nMill setup calculation.\nThe term \"setup\" is used for the calculation of the actuator settings required by each mill stand to roll the product. These settings include the initial screw-down position, the main drive speed, and the entry and exit tension references where applicable.\nThis setup calculation is normally performed either in a lower-level computer or a PLC that controls a rolling mill stand(s).\nA graphical representation of a mill model can be obtained by plotting the mill stand spring curve and the compression curve for the strip against the same distance axes; then the intersection point gives the solution of expected rolling force , and final Strip Thickness , and also the required initial screw-down position . See graph 3.\nIn its simplest form\nThis equation is known as the BISRA equation. It is also known as the gaugemeter equation because measurements of and can be used to calculate the exit thickness as measured by an instrument called a thickness gauge.\nIf the work rolls are initially pressed together by the screw-downs, then there will be a force acting between the top and bottom work rolls before the strip is present. In this situation, the Mill is said to be set \"below face\", as shown in graph 3. This is often the case with thin strip.\nHowever, if there is an actual gap before the metal enters the mill, then will be zero, and (from equation 1) must be greater than \nThe calculation is repeated for the following stands with the exit thickness of the one stand becoming the entry thickness of the next stand. Note that the compression curve has a greater or lesser elastic region depending on the entry and exit tension stresses of that next stand.\nInterstand tensions.\nOne could say the steel is compressed by the force of the work rolls, equivalent to forging; however, if there are tensions present, then it could be said that the steel is stretched by the tension pulling it through the rotating work rolls, as in extruding through a die. See sketch 3.\nThe tensions reduce the effective elasticity of the product by an amount equal to the induced tension strain. This tension effect is represented in graphs 2 and 3 by drawing the steel compression curve with the elastic region reduced accordingly.\nThe relationship of the rolling force to the entry and exit strip tensions is important in determining the finished strip flatness. Too much force produces strip with edge wave (often called \"pressure wave\"). Too much tension, that is too little force, can cause center buckle (depending on the crown of the rolls).\nThe tension stress is 30% to 50% of the yield stress for cold mills and often higher in hot mills (which can result in heavy necking and even strip breaks).\nIn sketch 4, observe that the force is offset from the work roll centers because the strip is thicker at the entry than at the exit; this is one component of the torque that the main drives must supply. The other component is the difference in the tension forces. If the exit tension force is much greater than the entry tension force, then the tension torque may be larger than the torque due to the rolling-force and the main drives will generate power.\nThe neutral point, or no-slip point is the point within the roll bite where the work rolls and the strip are doing the same speed.\nThe position of the neutral point is influenced by the entry and exit tensions.\nShudder occurs when the neutral point is at an edge of the roll bite; that is the work rolls are alternately grabbing the strip and letting it slip.\nForward slip is the ratio of the exit strip speed to the work rolls peripheral speed. Backward slip is the ratio of the entry strip speed to the work rolls peripheral speed.\nRoll wear.\nAs the strip slides through the work rolls it polishes them and the strip. This changes the friction coefficient of the strip-to-roll surface. So, to predict the forces and the power required to drive the work rolls, the mill modelling estimates this roll wear based on the length of strip rolled.\nTo reduce the friction in the roll bite, a warm oil-water emulsion is sprayed at the entry side of the roll bite in cold rolling mills.\nThe work rolls of all the stands in a tandem mill are normally changed at the same time. The new work rolls will have been ground to restore their desired crown and roughness. When this is done, the roll wear is reset to zero in the modelling.\nThe heat generated in the roll bite of a cold mill warms both the strip and the rolls. Since the cold mill rolls have no coolant applied, just a small amount of warm oil-water emulsion, the work rolls in a cold mill become hotter than those in a hot mill, where copious amounts of cold water are sprayed at the exit side of the roll bite.\nBack-up roll bearings speed effect.\nThe back-up roll bearings are usually white-metal bearings which rely on a film of oil between the shaft and the white-metal to reduce the friction; as seen in sketch 5.\nAs the speed increases more oil is dragged into the active region of the bearing and this increases the thickness of the oil film in this region. This pushes the top work roll down and the bottom work roll up, which reduces the roll gap in the same manner as running the screws down. To compensate for this, most screw-down control loops include a feed-forward parameter derived from either; an equation of rolling speed, or a value extracted from a lookup table using linear interpolation.\nTo ensure an oil film exists even at zero speed; pumps are often used to force oil through very tiny holes into the bearing's active region; this is referred to as hydrostatics.\nIn Chart 1, the scale for the screw-downs position (mauve trace) was 0.2mm per division; this was too coarse. Consequently Chart 2 was created from a similar coil, but with a screw-down position scale of 0.06mm per division; that is, from 5.8mm to 6.4mm.\nIn the chart recordings, notice that the force (light green trace) has been held constant by the automatic control, which has raised the screw-downs (mauve trace) as the speed (red trace) has increased. This increase in screw position is a measure of the white metal bearing speed effect.\nFor a more accurate measurement, the force of each mill stand is measured as it is run through its speed range without strip present.\nThe values measured from Chart 2 were plotted in an Excel spreadsheet. The equation that was used to match the measured points was .\nNote that the use of oil hydrostatics can hold the oil film nearly constant up to about 20% of full speed; hence no screw-down movement would be required in that low speed range (this is shown as the red line in the graph of the measured points).\nNow recall the gaugemeter equation in its simplest form:\nThis equation is modified to include the backup roll bearing speed effect especially when rolling product which has a thickness similar to the speed effect (~400 μm at some temper mills). Thus,\nDiscontinuity in the stress verses strain of annealed steel.\nThe discontinuity in the stress/strain of annealed steel makes it impossible to create round tinned steel-cans. Wherever the steel bends first is where most of the bending will occur, rather than uniformly.\nThe discontinuity is shown within the red circle in graph 4. It is the reason the strip is given a light reduction (~1.3%) normally referred to as an elongation or extension.\nSince it is referred to as an elongation and not a reduction, this strip is said to have been reduced only once (at the cold mill prior to annealing); hence the term single reduced (SR).\nAfter the elongation, the discontinuity is no longer present.\nAlternatively; after annealing, the steel strip can be reduced a second time (by up to 30%) to make it both thinner and work hardened. When this is done, the strip is said to have been reduced twice; that is, doubled reduced (DR).\nGrade adaption.\nWhile a tandem mill is rolling, the \"setup\" computer collects the following information:\nIt also has available the coil's schedule information:\nThe actual rolling forces are compared with the forces predicted by the mill model given the information obtained. Any differences adjust the calculated forces by trimming the force adaptors, . Thus equation 5 becomes\nRecall that equation 3 gave the compressive strength of steel at BlueScope steel's 5 stand cold mill\nThe average value of the force adaptors trimmed the value of for the actual grade being rolled.\nAlso the slope of the force adaptors corrected the work hardening rate, for the same grade of steel. The value of for super-strapping was approximately twice that for normal tin-plate.\nThis made switching between grades from coil-to-coil much smoother.\nThreading.\nA few difficulties arise when threading any tandem cold mill.\nOne way to minimize these problems is to use \"open-gap\" threading.\nWith open-gap threading, the next stand to be threaded has a roll gap greater than the thickness of the strip. Once threaded, the top work roll is lowered onto the strip and then the strip moves on. Open-gap threading ensures that the head-end does not mark the work rolls as it enters the roll-gap. And having the strip stopped as the screw-downs are lowered avoids skidding as the work roll just touch the strip.\nFor \"closed-gap\" threading of a tandem mill, it is important that the head-end of the strip remains flat so that it enters the next stand easily. Immediately the strip enters a stand, there is no tension on either side of it; this means that the force would be greater than during rolling, so the roll gap (screw-downs) initially needs to be increased a little with respect to that required during rolling in order to prevent excessive edge-wave.\nThe closed-gap screw-down setting is calculated using the mill model for thread speed and with no tensions.\nAnother issue with closed-gap threading is the speed of the stand being threaded.\nIt needs to be faster than the proceeding stand, so that the strip doesn't build up between the stands; but not so fast that it pulls the strip taught too quickly and breaks the strip.\nIn all cases, the strip's head-end will remain thicker because of the lack of tensions as it is threaded; consequently there will be a sizeable amount of head-end off-gauge strip that must be scrapped later.\nNotice in the gif simulation, that the head-end speed remained constant when moving.\nThis was the practice at BlueScope Steel's 5 stand cold mill.\nControl issues.\nThe control of a tandem rolling mill is multi-layered.\nTwo examples are shown for BlueScope Steel's No.2 temper mill with the exit stand configured for strip shape (flatness).\nAt the lowest level is the current/voltage control of the DC electrical drive motors.\nAt this level the bridles and reels are in open-loop tension mode; this means they run with a voltage which is related to the strip speed and a current controlled according to the tension required in the nearby strip. The tension reel has a motoring current to pull the strip taught, and the payoff reel generates to pull back against the strip. To keep these tensions constant during acceleration/deceleration of the mill, an additional current must be applied to the reels and bridles to produce the extra torque required to accelerate/decelerate them, especially when there is a large part of a coil on a reel. This is referred to as “inertia compensation”.\nAbove the direct motor controls, is the last stand's force control which sets the strip flatness. The rolls heat up slowly while processing a coil, and this would close the roll gap and increase the rolling force; however, to prevent this increase, the force control raises the screw-downs occasionally, as required.\nAlso at this level is the inter-stand tension control. It can act into either of the adjacent stands, but as in the diagrams shown, it acted into both stands in the proportions shown.\nThe thickness/elongation controls and speed profile sit above all of the other control loops.\nThe speed profile is determined in the mathematic modelling according to the desired reduction. It is multiplied by the master ramp's speed as set by the operator using his/her inputs, which are: thread (go to thread speed); run (accelerate to top speed); hold (stop acceleration/deceleration); stop (steady deceleration to zero speed); and emergency stop (uses maximum deceleration possible).\nBack-up roll eccentricity.\nWith hot rolled slabs and plates, the thickness varies mainly due to the changes in the temperature along the length. The colder sections are a result of the supports in the re-heat furnace.\nWhen cold rolling, virtually all of the strip thickness variation is the result of the eccentricity and out-of-roundness of the back-up rolls from about stand three of the hot strip mill through to the finished product. \nThe back-up roll eccentricity can be up to 100 μm in magnitude per stack. The eccentricity can be measured off-line by plotting the force variation against time with the mill on creep, no strip present, and the mill stand below face.\nA modified fourier analysis was employed by the five stand cold mill at Bluescope Steel, Port Kembla from 1986 until that cold mill ceased production in 2009. Within each coil, the exit thickness deviation times 10 for every meter of strip was stored in a file. This file was analyzed separately for each frequency/wavelength from 5m to 60m in steps of 0.1m. To improve the accuracy, care was taken to use a full multiple of each wavelength (100*). The calculate amplitudes were plotted against the wavelength, so that the spikes could be compared to the expected wavelengths created by the backup rolls of each stand.\nIf a mill stand is fitted with hydraulic pistons in series with, or instead of the electrically driven mechanical screws, then it is possible to eliminate the effect of that stands back-up roll eccentricity. While rolling, the eccentricity of each back-up roll is determined by sampling the roll force and assigning it to the corresponding portion of each back-up roll's rotational position. These recordings are then used to operate the hydraulic piston so as to neutralize the eccentricities.\nSensitivities and their uses.\nIn a tandem rolling mill, the gearing of the screw-downs is normally large enough that the work rolls can be moved during rolling. With such a ratio the worm gear is said to be self-locking; that is, the rolling force is unable to push through the worm drive and rotate the electrical drive motor. This means that no brake is attached to the electrical motor.\nIf during rolling, it is necessary to move the screw-downs to correct either the rolling force or the exit strip thickness, then consider the triangle, shown circled in the graph 5 and enlarged in sketch 6, created when the screw-downs are moved down from the purple line to the green line.\nThe strip becomes thinner and the rolling force increases.\n with , but the slope , and the slope \nTherefore, \nWhich gives\nThis term is used to ensure that the control of the rolling force using the screws is independent of the metal being rolled.\nUsing gives\nThis factor is used to guarantee that the control of the exit thickness by the screws is independent of the metal being rolled.\nThe process sensitivities are highly product dependent, so to obtain reasonable values they are calculated off-line in the setup computer, and then incorporated in the real-time control systems.\nMass flow.\nA rolling mill does not create nor destroy steel during normal steady state rolling. That is, the same mass of steel leaves the mill as entered it.\nAnd so; expressing the entry volume as , and the exit volume \nThe density is unaffected by the rolling process and can be cancelled out.\nThe width may change, but it does so by an insignificant amount (only a fraction of the strip thickness), and so the change may be ignored when rolling thin (<1mm) strip. The roll force tends to widen the strip, while the entry and exit tensions (when present) tend to make the strip narrower.\nSo, cancelling the density , the width , and the time , gives\nThis can be used in a rolling mill to calculate the exit thickness that the X-ray gauge will measure when the corresponding portion of the strip finally reaches the gauge.\nBy assuming all of the cold mill head-end off-gauge has been completely removed by the previous continuous annealing line; the scheduled entry thickness can be substituted in place of the actual entry thickness, .\nThen the entry bridle and exit bridle speeds can be used as the measurements of entry speed, and exit speed, respectively.\nThe resulting calculated thickness deviation can be seen as the light blue trace in chart recording 3. Notice that the thickness control was working at thread speed (red trace). In the block diagram, the calculated gauge (thickness) is q62 and the thickness error is q66. Note the use of the sensitivity factor dS/dh as q2. There are two other interesting factors with this control:\nA bumpless PI control.\nInitially the control appears to be a PD control with q18 containing a P term equal to q16 times the gain q4, plus a D term being the constant q10 times the change in q16. However, since q20 is effectively added to itself, this summation converts the P term into an integral, and the D term becomes a proportional term. This arrangement has the advantage that the gains q4 and q10 can be changed while the control loop is active without causing a step in the output q20; that is, it's a bumpless control. The overall maximum/minimum limit is designed to prevent the equivalent of integral windup.\nAn NIC trim into the inter-stand tension control.\nNormally moving the screw-downs to correct the strip thickness would perturb the inter-stand tension; its control would then need to trim the speed of the appropriate stand to restore the tension. So, what is required, is a compensating trim applied to the tension control at the same time as the thickness trim goes to the screw-downs. This is referred to as a non-interactive control;\nthat is, the thickness correction no-longer disturbs the tension. In the block diagram, the screw trim q20 is converted into a compensating IS tension trim using the sensitivity factor dT/dS (the value of this was measured by applying a small step change to the thickness reference and looking for any change in the IS tension).\nFor the coil in chart recording 1 above, the cold mill Head-end off-gauge was not fully removed at the CA line; this can be seen as the difference between the X-ray deviation (green trace) and the calculated thickness deviation (light blue trace).\nBridle rolls.\nBridle rolls are used to increase or decrease the strip tension in a processing line or rolling mill.\nThe bridle rolls normally come in a set of two, three, or four rolls of equal diameter, with each roll individually powered by an electric motor/generator. The drives of the entry bridle generate power as they pull back and increase the strip tension after them. This power is partly provided by the exit bridle which pulls on the strip before it, and so decreases the strip tension after it.\nTo assist with threading there are normally guides and even a pinch roll or rolls, as shown for the two roll bridle in sketch 7.\nTo determine the size of the electrical drives, it is necessary to calculate the values of the intermediate tension or tensions.\nThe maximum tension difference across a single bridle roll is determined by the wrap angle (in radians) of the strip around that roll, and the roll-to-strip sliding friction , i.e.\nThe power required to drive such a bridle is , i.e. \nThe electrical power required by the drive motor = volts ⋅ amps. The voltage can be regulated according to the strip speed, leaving the current to be proportional to the required tension change.\nTo prevent slippage, the bridle rolls within a set are operated at only a fraction of the maximum tension difference, so the actual tension difference across each bridle roll will be . That is, a lower value of friction is used in the calculations.\nConsider the simplest case:\nA two roll bridle set with both rolls having the same wrap angle . Then , and .\nTherefore which gives, \nAnd so\nNow consider an example:\nAnd so, the second bridle requires just over 40% more motor power compared to the first.\nIf one wishes to reduce the number of spares; then it is desirable to have motors of the same power.\nTo do that, the wrap angle on the first bridle must be increased so that the tension difference across both bridles is the same;\n. That is,\nLet the wrap angle of bridle roll 1 be , where is the wrap angle of bridle roll 2.\nThat is \nTaking logarithms of both sides gives\nFor bridle roll 2: \nAgain, taking logarithms gives\nFrom equations B4 and B5:\nNow consider a four roll bridle with tensions . Normally in such a bridle set, all of the rolls have the same strip wrap angle, as shown in sketch 7.\nThe wrap angle from to is the same as that from to .\nTherefore, using equation B2\nSimilarly,\nSo if we let then which gives \nAnd finally\nInter-stand tension control.\nConsider a violin string:\nNow consider the strip between the stands of a multi-stand mill:\nThe overall transfer function from speed-difference to tension is:\nTherefore, the control loop divides the tension error by the strip width and the strip thickness in order to have a consistent response.\nIn chart recording 4, the two components necessary to change the tension (brown trace) can be seen in the speed trim (light blue trace). There is the extra speed difference necessary to stretch the strip already in the inter-stand gap (large trim); and the slight increase in speed difference to maintain the new level of tension.\nStrip shape.\nStrip shape is one of the important quality factors of a finished strip, along with the thickness and the mechanical properties.\nPoor shape is revealed when the strip fails to lie flat when placed unrestrained on a flat surface. To perform this test, a sample of strip is taken at least 3 wraps in from the end of the finished coil; this is called a \"run-out\".\nShape errors occur when the strip has not been rolled uniformly across its width.\nThe problem is, that strip shape cannot be seen while the strip is being rolled because it is under tension; hence the need to do a run-out.\nThe main shape defects are:\nAn error in shape is quoted in I-units. If part of 100m of strip is rolled 1mm longer than the rest, then it is in error by one I-unit.\nThere are a few ways in which the shape can be influenced:\nCoil collapse.\nIf a coil of thin strip is wound with low tension,\nthen it may not have the strength to support itself and may collapse, especially if roughly handled, see figure 1(a).\nA solution is to provide chocks to support the coils more appropriately.\nIf a large coil is wound with a high tension,\nthen the tension stress builds up on the inner wraps and can cause them to kink, as seen in figure 1(b).\nAn early solution was to place a steel sleeve onto the tension reel mandrel before the coil started.\nHowever, loading the sleeve slowed production, and the handling of the sleeves back from the following production lines added an extra cost.\nFigure 1(c) shows a coil with a sleeve sitting on chocks.\nIndustrial Automation Services devised a solution.\nThe early wraps are wound with a high tension to create a pseudo sleeve,\nthen the body of the coil is wound with a moderate tension supported by that pseudo sleeve; as shown in figure 1(d).\nComputers and HMI.\nIn the 1980's it became possible for digital displays to replace hard-wired headboard-mimics and operator control/display panels.\nThe descriptions below are based on the upgrade of BlueScope Steel's 5 stand cold mill in 1985.\nThere are normally three levels of computers directly associated with a tandem rolling mill, as shown in sketch 11.\nLevel 1 real-time control.\nAt the lowest level is a Programable Logic Controller, PLC or minicomputer.\nThe PLC or minicomputer contains the control loops that run the rolling mill. It receives inputs into these dynamic controls directly from the hard-wired desk\nand gets the targets for the exit thickness, the tensions and the screw-down positions from the setup computer.\nThe desk controls include the speed requests (the thread, run and stop push buttons), any screw-down movements\n(each joystick has raise, lower, tilt left, and tilt right), and the tension trims (increase / decrease toggle switches).\nLevel 2 batch processing.\nAt level 2 is a keyboard and screen having a menu-based interface into the setup computer's mill model.\nThis operator interface is normally described as the Human Machine Interface, HMI. Through this interface\nthe operator trims the setup for the next coil. He/she can trim the individual stand reductions, the inter-stand tensions, and the top speed as required.\nWhen the last stand has force control, then the rolling force can also be trimmed.\nAt this level there are a few TV monitors. At BlueScope Steel's cold mill these monitors included:\nActually these displays can be connected to either level 1 or level 2; for example, after the more recent (in 1997) BlueScope Steel upgrade of their 6 stand hot strip mill,\nthe operator displays are driven by the level 1 PLC's.\nLevel 3 supervision.\nThe setup computer gets each coil's primary data from a scheduling computer.\nThis scheduling computer usually receives the product's data from the previous production unit\nand will pass on the results of this mill's rolling to the next unit.\nThe primary data sent by the scheduling computer consists of the nominal entry thickness and width, the aim thickness, and if rolling a plate the aim width.\nThe scheduler assembles the coils or plates to be processed within each campaign using his/her Human Computer Interface, HCI terminal.\nA campaign begins with a scheduled roll change; that is, when all of the work rolls of the tandem mill are changed together.\nFor a cold tandem mill, the campaign has a coffin-shaped width profile. The first few coils are about 3/4 of the full width.\nGradually the coils become wider until the maximum product width is reached. This allows the thermal camber of the rolls to develop before rolling the full-width product.\nFrom then on the product becomes narrower, to avoid the excessive work roll wear corresponding to the strip edges.\nRolling mill definitions.\nThese definition only apply to the rolling of slabs, plates and strip in a rolling mill.\nReduction.\nReduction, is defined as the per-unit change in thickness with respect to the entry thickness , and so formula_1 formula_1where is the exit thickness.\nAs the material is reduced, its length becomes proportionately longer; this can be seen in the attached GIF movie.\nThere are many other definitions of the word reduction; such as in chemistry, medicine, surgery, safety, investment, and in a more general sense, such as in cooking and waste reduction, etc.\nElongation.\nWhen the reduction is small (<2%), it is normally referred to as an elongation or an extension.\nElongation, is defined as the per-unit increase in length due to a decrease in area with respect to the entry, regardless of shape.\nGiven an entry length , then formula_1 formula_1where is the final length.\nIf the width is unaffected (as is the case when rolling thin strip <2mm, see sketch 12), then the mass flow concept, gives formula_1 \nWhen the elongation is large it is normally measured as reduction, which is defined as the per-unit change in thickness with respect to the entry thickness ; and so if is the exit thickness,\nNote that the thickness difference is divided by the exit thickness for elongation and by the entry thickness with reduction; so they are not identical.\nAn elongation of typically 1.3% is performed to eliminate the discontinuity (seen at the yield point in graph 6) in the stress verses strain reaction of thin steel strip before it is tinned ready for making cans intended for containing preserved foods.\nThere are many other definitions of the word elongation; such as in astronomy, plasma physics, genetics, and in a more general sense, such as referring to the lengthening of an elastic band.", "Engineering,_Manufacturing": 0.9999285936, "qwen": "Yes"}
{"id": "29631466", "revid": "39191556", "url": "https://en.wikipedia.org/wiki?curid=29631466", "title": "Low plastic water bottle", "text": "A low plastic water bottle is one that uses less plastic than a regular water bottle, typically by having the same internal volume but being made from thinner plastic. Some such bottles have less than half the plastic of a regular water bottle.\nThe low plastic water bottle has seen an increase in production over the last few years. This is mainly because making low plastic bottles is more efficient, cost-effective, and more environmentally friendly than producing regular bottles. A large number of water companies now exclusively use a low plastic design for their 16.9 oz bottles.\nRecycling.\nCompanies have also taken recycling into consideration. Previously when water bottles were bought in packs of 24, there was a plastic wrap around the bottles and there was a cardboard base. This packaging was not recyclable, but now some water companies have made the packaging fully recyclable, and also have eliminated the cardboard base. Eliminating the cardboard base saves 20 million pounds of corrugated material annually. The plastic reduction in the bottles themselves saves 75 million pounds of plastic.\nThinner plastic bottles are harder to recycle. The average yield of PET bottle recycling in Europe dropped from 73% to 63% between 2011 and 2017, with low-plastic bottles being blamed for a higher moisture content in recycling bales, and for producing thinner plastic flakes which are more likely to be discarded during the recycling process.\nReplacements for plastics.\nAt least one other commercial attempt has been made toward the creation of cheap, non-plastic containers for water. In 2009, Ecologic Brands, Inc. released a water bottle which was created using a combination of recyclable, sustainable sheet stock such as bamboo or palm leaves. The design was entered into INNOVIC's Next Big Thing Award for 2009. The company has since gone on to create a paper jug which can be used as a holder for a recyclable plastic bag for liquids such as milk and detergent.", "Engineering,_Manufacturing": 0.9866911173, "qwen": "Yes"}
{"id": "7802134", "revid": "32990417", "url": "https://en.wikipedia.org/wiki?curid=7802134", "title": "Rösle", "text": "Rösle is a kitchen accessory manufacturer based in the small Bavarian town of Marktoberdorf in Germany. Rösle developed the Open Kitchen concept. Originally started in 1888 by Karl Theodor Rösle as an industrial roofing manufacturer, Rösle expanded into kitchen utensils prior to World War II. The company saw rapid growth throughout the 1950s and onwards and in 1993 the Rösle brand became solely dedicated to kitchen tools. In 2012, RÖSLE started their own BBQ range.\nProduction changes.\nIn 2009 the company closed its factory in Germany and sub-contracted production to various firms in China. While insisting the quality would remain, consumer feedback has been poor, leading to a growing market for used, German-made Rösle products.\nAs of 2022, the Masterclass sub-brand of knives are made in Solingen, Germany. ", "Engineering,_Manufacturing": 0.9987648726, "qwen": "Yes"}
{"id": "7815335", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=7815335", "title": "Product engineering", "text": "Product engineering refer to the process of designing and developing a device, assembly, or system such that it be produced as an item for sale through some product manufacturing process. Product engineering usually entails activity dealing with issues of cost, producibility, quality, performance, reliability, serviceability, intended lifespan and user features. These product characteristics are generally all sought in the attempt to make the resulting product attractive to its intended market and a successful contributor to the business of the organization that intends to offer the product to that market. It includes design, development and transitioning to manufacturing of the product. The term encompasses developing the concept of the product and the design and development of its hardware and software components. After the initial design and development is done, transitioning the product to manufacture it in volumes is considered part of product engineering.\nFor example, the engineering of a digital camera would include defining the feature set, design of the optics, the physical, aesthetic and ergonomic design of the packaging, developing the various electrical and mechanical component for the capture, processing and storage of image and developing the software that allows the user to see the pictures, store them in memory and download them to a computer.\nProduct engineering is an engineering discipline that deals with both design and manufacturing aspects of a product.\nArea of responsibility.\nProduct engineers are the technical interface between the component development team and the production side (Front End and Back End), especially after the development phase and qualifications when the high volume production is running.\nProduct engineers improve the product quality and secure the product reliability by balancing the cost of tests and tests coverage that could impact the production fall-off. They support failure analysis request from customers.\nKnowledge and skills.\nThe job requires the product engineer to have a very good working knowledge of:\nTools.\nA product engineer will use a wide range of tools and software, possibly including:\n20/20, AutoCad, CATIA, PTC Creo, Solidworks, Unigraphics, Labview, JMP, DataConductor.", "Engineering,_Manufacturing": 0.9999307394, "qwen": "Yes"}
{"id": "7815577", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=7815577", "title": "Automated optical inspection", "text": "Automated optical inspection (AOI) is an automated visual inspection of printed circuit board (PCB) (or LCD, transistor) manufacture where a camera autonomously scans the device under test for both catastrophic failure (e.g. missing component) and quality defects (e.g. fillet size or shape or component skew). It is commonly used in the manufacturing process because it is a non-contact test method. It is implemented at many stages through the manufacturing process including bare board inspection, solder paste inspection (SPI), pre-reflow and post-re-flow as well as other stages.\nHistorically, the primary place for AOI systems has been after solder re-flow or \"post-production.\" Mainly because, post-re-flow AOI systems can inspect for most types of defects (component placement, solder shorts, missing solder, etc.) at one place in the line with one single system. In this way the faulty boards are reworked and the other boards are sent to the next process stage.\nSMT inspection.\nAOIs for a PCB board with components may inspect the following features:\nAOI can be used in the following locations in the SMT lines: post paste, pre-reflow, post-reflow, or wave areas.\nBare PCB inspection.\nAOI for a bare PCB board inspection may detect these features:\nThe triggering of a defects report may be either rule-based (e.g. no lines on the board should be smaller than 50μ) or CAD based in which the board is locally compared with the intended design.\nThis inspection is much more reliable and repeatable than manual visual inspection.\nIn many cases, smaller circuit board designs are driving up the demand for AOI vs in-circuit testing.\nRelated technologies.\nThe following are related technologies and are also used in electronic production to test for the correct operation of electronics printed circuit boards:\nReferences.\n4. Automated Optical Inspection (AOI) Equipment List", "Engineering,_Manufacturing": 1.0000009537, "qwen": "Yes"}
{"id": "6139788", "revid": "40561892", "url": "https://en.wikipedia.org/wiki?curid=6139788", "title": "Bending (metalworking)", "text": "Bending is a manufacturing process that produces a V-shape, U-shape, or channel shape along a straight axis in ductile materials, most commonly sheet metal. Commonly used equipment include box and pan brakes, brake presses, and other specialized machine presses. Typical products that are made like this are boxes such as electrical enclosures and rectangular ductwork.\nProcess.\nIn press brake forming, a work piece is positioned over the die block and the die block presses the sheet to form a shape. Usually bending has to overcome both tensile stresses and compressive stresses. When bending is done, the residual stresses cause the material to \"\" towards its original position, so the sheet must be over-bent to achieve the proper bend angle. The amount of spring back is dependent on the material, and the type of forming. When sheet metal is bent, it stretches in length. The \"bend deduction\" is the amount the sheet metal will stretch when bent as measured from the outside edges of the bend. The \"bend radius\" refers to the inside radius. The formed bend radius is dependent upon the dies used, the material properties, and the material thickness.\nThe U-punch forms a U-shape with a single punch.\nTypes.\nThere are three basic types of bending on a press brake, each is defined by the relationship of the end tool position to the thickness of the material. These three are Air Bending, Bottoming and Coining. The configuration of the tools for these three types of bending are nearly identical. A die with a long rail form tool with a radiused tip that locates the inside profile of the bend is called a punch. Punches are usually attached to the ram of the machine by clamps and move to produce the bending force. A die with a long rail form tool that has concave or V shaped lengthwise channel that locate the outside profile of the form is called a die. Dies are usually stationary and located under the material on the bed of the machine. Note that some locations do not differentiate between the two different kinds of dies (punches and dies). The other types of bending listed use specially designed tools or machines to perform the work.\nAir bending.\nThis bending method forms material by pressing a punch (also called the upper or top die) into the material, forcing it into a bottom V-die, which is mounted on the press. The punch forms the bend so that the distance between the punch and the side wall of the V is greater than the material thickness (T).\nEither a V-shaped or square opening may be used in the bottom die (dies are frequently referred to as tools or tooling). Because it requires less bend force, air bending tends to use smaller tools than other methods.\nSome of the newer bottom tools are adjustable, so, by using a single set of top and bottom tools and varying press-stroke depth, different profiles and products can be produced. Different materials and thicknesses can be bent in varying bend angles, adding the advantage of flexibility to air bending. There are also fewer tool changes, thus, higher productivity.\nA disadvantage of air bending is that, because the sheet does not stay in full contact with the dies, it is not as precise as some other methods, and stroke depth must be kept very accurate. Variations in the thickness of the material and wear on the tools can result in defects in parts produced. Thus, the use of adequate process models is important.\nAir bending's angle accuracy is approximately ±0.5 deg. Angle accuracy is ensured by applying a value to the width of the V opening, ranging from 6 T (six times material thickness) for sheets to 3 mm thick to 12 T for sheets more than 10 mm thick. Springback depends on material properties, influencing the resulting bend angle.\nDepending on material properties, the sheet may be overbent to compensate for springback.\nAir bending does not require the bottom tool to have the same radius as the punch. Bend radius is determined by material elasticity rather than tool shape.\nThe flexibility and relatively low tonnage required by air bending are helping to make it a popular choice. Quality problems associated with this method are countered by angle-measuring systems, clamps and crowning systems adjustable along the x and y axes, and wear-resistant tools.\nThe K-factor approximations given below are more likely to be accurate for air bending than the other types of bending due to the lower forces involved in the forming process.\nBottoming.\nIn bottoming, the sheet is forced against the V opening in the bottom tool. U-shaped openings cannot be used. Space is left between the sheet and the bottom of the V opening. The optimum width of the V opening is 6 T (T stands for material thickness) for sheets about 3 mm thick, up to about 12 T for 12 mm thick sheets. The bending radius must be at least 0.8 T to 2 T for sheet steel. Larger bend radii require about the same force for bottoming as they do for air bending, however, smaller radii require greater force—up to five times as much—than air bending. Advantages of bottoming include greater accuracy and less springback. A disadvantage is that a different tool set is needed for each bend angle, sheet thickness, and material. In general, air bending is the preferred technique.\nCoining.\nIn coining, the top tool forces the material into the bottom die with 5 to 30 times the force of air bending, causing permanent deformation through the sheet. There is little, if any, spring back. Coining can produce an inside radius as low as 0.4 T, with a 5 T width of the V opening. While coining can attain high precision, higher costs mean that it is not often used.\nThree-point bending.\nThree-point bending is a newer process that uses a die with an adjustable-height bottom tool, moved by a servo motor. The height can be set within 0.01 mm. Adjustments between the ram and the upper tool are made using a hydraulic cushion, which accommodates deviations in sheet thickness. Three-point bending can achieve bend angles with 0.25 deg. precision. While three-point bending permits high flexibility and precision, it also entails high costs and there are fewer tools readily available. It is being used mostly in high-value niche markets.\nFolding.\nIn folding, clamping beams hold the longer side of the sheet. The beam rises and folds the sheet around a bend profile. The bend beam can move the sheet up or down, permitting the fabricating of parts with positive and negative bend angles. The resulting bend angle is influenced by the folding angle of the beam, tool geometry, and material properties. Large sheets can be handled in this process, making the operation easily automated. There is little risk of surface damage to the sheet.\nWiping.\nIn wiping, the longest end of the sheet is clamped, then the tool moves up and down, bending the sheet around the bend profile. Though faster than folding, wiping has a higher risk of producing scratches or otherwise damaging the sheet, because the tool is moving over the sheet surface. The risk increases if sharp angles are being produced.\nThis method will typically bottom or coin the material to set the edge to help overcome springback. In this bending method, the radius of the bottom die determines the final bending radius.\nRotary bending.\nRotary bending is similar to wiping but the top die is made of a freely rotating cylinder with the final formed shape cut into it and a matching bottom die. On contact with the sheet, the roll contacts on two points and it rotates as the forming process bends the sheet. This bending method is typically considered a \"non-marking\" forming process suitable to pre-painted or easily marred surfaces. This bending process can produce angles greater than 90° in a single hit on standard press brakes process.\nRoll bending.\nThe roll bending process induces a curve into bar or plate workpieces.\nThere should be proper pre-punching allowance.\nElastomer bending.\nIn this method, the bottom V-die is replaced by a flat pad of urethane or rubber. As the punch forms the part, the urethane deflects and allows the material to form around the punch. This bending method has a number of advantages. The urethane will wrap the material around the punch and the end bend radius will be very close to the actual radius on the punch. It provides a non-marring bend and is suitable for pre-painted or sensitive materials. Using a special punch called a \"radius ruler\" with relieved areas on the urethane U-bends greater than 180° can be achieved in one hit, something that is not possible with conventional press tooling. Urethane tooling should be considered a consumable item and while they are not cheap, they are a fraction of the cost of dedicated steel. It also has some drawbacks, this method requires tonnage similar to bottoming and coining and does not do well on flanges that are irregular in shape, that is where the edge of the bent flange is not parallel to the bend and is short enough to engage the urethane pad.\nJoggling.\nJoggling, also known as joggle bending, is an offset bending process in which two opposite bends with equal angles are formed in a single action creating a small s-shape bend profile and an offset between the unbent face and the result flange that is typically less than 5 material thicknesses. Often the offset will be one material thickness, in order to allow a lap joint where the edge of one sheet of material is laid on top of the other.\nCalculations.\nMany variations of these formulas exist and are readily available online. These variations may often seem to be at odds with one another, but they are invariably the same formulas simplified or combined. What is presented here are the unsimplified formulas.\nAll formulas use the following keys:\nThe \"neutral line\" (also called the Neutral axis) is an imaginary profile that can be drawn through a cross-section of the workpiece that represents the locus where no tensile or compressive stress are present but shear stresses are at their maximum. In the bend region, the material between the neutral line and the \"inside\" radius will be under \"compression\" during the bend while the material between the neutral line and the \"outside\" radius will be under \"tension\" during the bend. Its location in the material is a function of the forces used to form the part and the material yield and tensile strengths. This theoretical definition also coincides with the geometric definition of the plane representing the unbent flat pattern shape within the cross-section of the bent part. Furthermore, the bend allowance (see below) in air bending depends primarily on the width of the opening of the bottom die. As a result, the bending process is more complicated than it appears to be at first sight.\nBoth bend deduction and bend allowance represent the difference between the neutral line or unbent \"flat pattern\" (the required length of the material prior to bending) and the formed bend. Subtracting them from the combined length of both flanges gives the flat pattern length. The question of which to use is determined by the dimensioning method used to define the flanges as shown in the two diagrams below. The flat pattern length is always shorter in length than the sum of all the flange length dimensions due to the geometric transformation. This gives rise to the common perspective that that material is stretching during bending and the bend deduction and bend allowance are the distance that each bend stretches. While a helpful way to look at it, a careful examination of the formulas and stresses involved show this to be false.\nMost 3D Solid Modeling CAD software has sheet metal functions or add-ons that performs these calculations automatically.\nBend allowance.\nThe \"bend allowance\" (BA) is the length of the arc of the neutral line between the tangent points of a bend in any material. Adding the length of each flange as dimensioned by B in the diagram to the BA gives the Flat Pattern length. This bend allowance formula is used to determine the flat pattern length when a bend is dimensioned from 1) the center of the radius, 2) a tangent point of the radius (B) or 3) the outside tangent point of the radius on an acute angle bend (C). When dimensioned to the outside tangent, the material thickness and bend radius are subtracted from it to find the dimension to the tangent point of the radius before adding in the bend allowance.\nThe BA can be estimated using the following formula, which incorporates the empirical K-factor:\nBend deduction.\nThe bend deduction BD is defined as the difference between the sum of the flange lengths (from the edge to the apex) and the initial flat length.\nThe \"outside set back\" (OSSB) is the length from the tangent point of the radius to the apex of the outside of the bend. The \"bend deduction\" (BD) is twice the outside setback minus the bend allowance. BD is calculated using the following formula, where A is the angle in radians (=degrees*π/180):\nFor bends at 90 degrees this formula can be simplified to:\nK-factor.\n\"K-factor\" is a ratio of the location of the neutral line to the material thickness as defined by t/T where t = location of the neutral line and T = material thickness. The K-factor formula does not take the forming stresses into account but is simply a geometric calculation of the location of the neutral line after the forces are applied and is thus the roll-up of all the unknown (error) factors for a given setup. The K-factor depends on many variable including the material, the type of bending operation (coining, bottoming, air-bending, etc.) the tools, etc. and is typically between 0.3 and 0.5.\nThe following equation relates the K-factor to the bend allowance:\nThe following table is a \"rule of thumb\". Actual results may vary remarkably.\nThe following formula can be used in place of the table as a good \"approximation\" of the K-factor for air bending:\nAdvantages and disadvantages.\nBending is a cost-effective near net shape process when used for low to medium quantities. Parts usually are lightweight with good mechanical properties. A disadvantage is that some process variants are sensitive to variations in material properties. For instance, differences in spring-back have a direct influence on the resulting bend angle. To mitigate this, various methods for in-process control have been developed. Other approaches include combining brakeforming with incremental forming.\nBroadly speaking, each bend corresponds with a set-up (although sometimes, multiple bends can be formed simultaneously). The relatively large number of set-ups and the geometrical changes during bending make it difficult to address tolerances and bending errors a priori during set-up planning, although some attempts have been made", "Engineering,_Manufacturing": 1.0000025034, "qwen": "Yes"}
{"id": "418883", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=418883", "title": "Monopoly profit", "text": "Monopoly profit is an inflated level of profit due to the monopolistic practices of an enterprise.\nBasic classical and neoclassical theory.\nTraditional economics state that in a competitive market, no firm can command elevated premiums for the price of goods and services as a result of sufficient competition. In contrast, insufficient competition can provide a producer with disproportionate pricing power. Withholding production to drive prices higher produces additional profit, which is called \"monopoly profits\".\nAccording to classical and neoclassical economic thought, firms in a perfectly competitive market are price takers because no firm can charge a price that is different from the equilibrium price set within the entire industry's perfectly competitive market. Since a competitive market has many competing firms, a customer can buy widgets from any of the competing firms. Because of this tight competition, competing firms in a market each have their own horizontal demand curve that is fixed at a single price established by market equilibrium for the entire industry as a whole. Each firm in a competitive market has buyers for its product as long as the firm charges \"no more than\" the single price. Since firms cannot control the activities of other firms that produce the same widget sold within the market, a firm that charges a price that is higher than the industry's market equilibrium price would lose business; customers would respond by buying their widgets from other competing firms that charge the lower market equilibrium price, which makes deviation from the market equilibrium price impossible.\nPerfect competition is commonly characterized by an idealized situation in which all firms within the industry produce exact comparable goods that are perfect substitutes. With the exception of commodity markets, this idealized situation does not typically exist in many actual markets, but in many cases, there exist similar products that are easily interchangeable because they are close substitutes (for example, butter and margarine). A significant rise in a product's price tends to cause customers to switch from this good to a lower priced close substitute. In some cases, firms that produce differing but similar goods have similar production processes, which makes it relatively easy for one-good firms to switch their manufacturing processes to produce a different but similar good. This would be the case when the cost of changing the firm's manufacturing process to produce the similar good can be somewhat immaterial in relationship to the firm's overall profit and cost. Since consumers tend to replace goods whose prices are high with cheaper close substitutes, and the existence of close substitutes whose manufacturing processes are similar allows a firm producing a low-priced good to easily switch over to producing the other higher priced good, the competition model accurately explains why the existence of different similar goods form competitive forces that deny any single firm the ability to establish a monopoly in their product. This effect is observable in a high profit and production cost industry, such as the car industry, and other industries facing competition from imports. \nBy contrast, the lack of competition in a market ensures the firm (monopoly) has a downward sloping demand curve. Although raising prices causes the monopoly to lose some business, some sales can be made at higher prices. Although monopolists are constrained by consumer demand, they are not \"price takers\" because they can influence price through their production decisions. The monopolist can either have a \"target level of output\" that will ensure the monopoly price as the given consumer demand in the industry's market reacts to the fixed and limited market supply, or it can set a fixed monopoly price at the onset and adjust output until it can ensure no excess inventories occur at the final output level chosen. At each price, the firm must accept the level of output as determined by the market's consumer demand, and every output quantity is identified with a price that is determined by the market's consumer demand. The price and output are co-determined by consumer demand and the firm's production cost structure.\nA firm with monopoly power sets a monopoly price that maximizes the monopoly profit. The most profitable price for the monopoly occurs when output level ensures the marginal cost (MC) equals the marginal revenue (MR) associated with the demand curve. Under normal market conditions for a monopolist, this monopoly price is higher than the marginal (economic) cost of producing the product, indicating that the price paid by the consumer, which is equal to their marginal benefit, is above the firm's MC.\nPersistence.\nWithout barriers to entry and collusion in a market, the existence of a monopoly and monopoly profit cannot persist in the long run. Normally, when economic profit exists within an industry, economic agents form new firms in the industry to obtain at least a portion of the existing economic profit. As new firms enter the industry, they increase the supply of the product available in the market, and they are forced to charge a lower price to entice consumers to buy the additional supply they are supplying as competition. Since consumers flock toward the lowest price (in search of a bargain), older firms within the industry may lose their existing customers to the new firms entering the industry, and are forced to lower their prices to match the prices set by the new firms. New firms continue to enter the industry until the price of the product is lowered to the point that it is the same as the average economic cost of producing the product, and economic profit disappears. When this happens, economic agents outside of the industry find no advantage to entering the industry, supply of the product stops increasing, and the price charged for the product stabilizes.\nNormally, a firm that introduces a brand new product can initially secure a monopoly for a short while. At this stage, the initial price the consumer must pay for the product is high, and the demand for, as well as the availability of the product in the market, will be limited. As time passes, when the profitability of the product is well established, the number of firms that produce this product will increase until the available product supply becomes relatively large, and the product's price shrinks down to the level of the average economic cost of producing the product. When this occurs, all monopoly associated with producing and selling the product disappears, and the initial monopoly turns into a (perfectly) competitive industry.\nWhen consumers have complete information about the prices available in the market and the quality of the products sold by the various firms, there cannot be a persistent monopolistic situation in the absence of barriers to entry and collusion. Various barriers to entry include patent rights and the monopolization of a natural resource needed to produce a product. The American firm Alcoa Aluminum is a historical example of a monopoly due to natural resource control; its control of \"practically every source of bauxite in the United States\" was one key reason that \"[it] was, for a long time, the sole producer of aluminum in the United States\".\nA barrier to entry can exist in a market situation that is characterized by a combination of high fixed costs in production and a relatively small demand within the firm's product market. Since a high fixed cost results in a higher product market unit costs at lower production levels, and lower unit costs at higher production levels, the combination of a small product market demand for the firm's product, and the high revenue levels the firm needs to cover the high fixed costs it faces, indicate the product market will be dominated by a single large firm that uses economies of scale to minimize both its unit cost and its product price. New firms would be reticent to enter a product market if an apparent slim economic profit can turn into an immediate economic loss for all firms upon a new entry. However, since the qualities of most economic markets make them contestable markets, there may be a greater magnitude of product differentiation within this overall market structure, making it similar to monopolistic competition.\nGovernment intervention.\nCompetition laws were created to prevent powerful firms from using their economic power to artificially create the barriers to entry they need to protect their monopoly profits, including the use of predatory pricing toward smaller competitors. In the United States, Microsoft Corporation was initially convicted of breaking competition laws and engaging in anti-competitive behavior to form a barrier in \"United States v. Microsoft Corporation\"; after a successful appeal on technical grounds, Microsoft agreed to a settlement with the Department of Justice in which they were faced with stringent oversight procedures and explicit requirements designed to prevent the predatory behavior. The company was successfully convicted of similar anti-competitive behavior in the European Economic Community's second highest court, the Court of First Instance, in 2007. If firms in an industry collude they can also limit production to restrict supply, and ensure the price of the product remains high enough to ensure all of the firms in the industry achieve an economic profit.\nIf a government feels it is impractical to have a competitive market, it sometimes tries to regulate the monopoly by controlling the price the monopoly charges for its product. The old AT&T monopoly, which existed before the courts ordered its breakup and tried to force competition in the market, had to get government approval to raise its prices. The government examined the monopoly's costs and determined if the monopoly should be allowed to raise its price; if the government felt that the cost did not justify a higher price, it rejected the monopoly's application. Although a regulated monopoly will not have a monopoly profit that is high as it would be in an unregulated situation, it still can have an economic profit that is still above what a competitive firm has in a truly competitive market.", "Engineering,_Manufacturing": 0.9928175211, "qwen": "Yes"}
{"id": "41433885", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=41433885", "title": "Co-fired ceramic", "text": "Co-fired ceramic devices are monolithic, ceramic microelectronic devices where the entire ceramic support structure and any conductive, resistive, and dielectric materials are fired in a kiln at the same time. Typical devices include capacitors, inductors, resistors, transformers, and hybrid circuits. The technology is also used for robust assembly and packaging of electronic components multi-layer packaging in the electronics industry, such as military electronics, MEMS, microprocessor and RF applications.\nCo-fired ceramic devices are fabricated using a multilayer approach. The starting material is composite green tapes, consisting of ceramic particles mixed with polymer binders. The tapes are flexible and can be machined, for example, using cutting, milling, punching and embossing. Metal structures can be added to the layers, commonly using filling and screen printing. Individual tapes are then bonded together in a lamination procedure before the devices are fired in a kiln, where the polymer part of the tape is combusted and the ceramic particles sinter together, forming a hard and dense ceramic component.\nCo-firing can be divided into low-temperature (LTCC) and high-temperature (HTCC) applications: low temperature means that the sintering temperature is below , while high temperature is around . The lower sintering temperature for LTCC materials is made possible through the addition of a glassy phase to the ceramic, which lowers its melting temperature.\nDue to a multilayer approach based on glass-ceramics sheets, this technology offers the possibility to integrate into the LTCC body passive electrical components and conductor lines typically manufactured in thick-film technology. This differs from semiconductor device fabrication, where layers are processed serially, and each new layer is fabricated on top of previous layers.\nHistory.\nCo-fired ceramics were first developed in the late 1950s and early 1960s to make more robust capacitors. The technology was later expanded in the 1960s to include multilayer structures similar to printed circuit boards.\nComponents.\nHybrid circuits.\nLTCC technology is especially beneficial for RF and high-frequency applications. In RF and wireless applications, LTCC technology is also used to produce multilayer hybrid integrated circuits, which can include resistors, inductors, capacitors, and active components in the same package. In detail, these applications comprise mobile telecommunication devices (0.8–2 GHz), wireless local networks such as Bluetooth (2.4 GHz) to in-car radars (50–140 GHz, and 76 GHz). LTCC hybrids have a smaller initial (\"non recurring\") cost as compared with ICs, making them an attractive alternative to ASICs for small scale integration devices.\nInductors.\nInductors are formed by printing conductor windings on ferrite ceramic tape. Depending on the desired inductance and current carrying capabilities a partial winding to several windings may be printed on each layer. Under certain circumstances, a non-ferrite ceramic may be used. This is most common for hybrid circuits where capacitors, inductors, and resistors will all be present and for high operating frequency applications where the hysteresis loop of the ferrite becomes an issue.\nResistors.\nResistors may be embedded components or added to the top layer post-firing. Using screen printing, a resistor paste is printed onto the LTCC surface, from which resistances needed in the circuit are generated. When fired, these resistors deviate from their design value (±25%) and therefore require adjustment to meet the final tolerance. With Laser trimming one can achieve these resistances with different cut forms to the exact resistance value (±1%) desired. With this procedure, the need for additional discrete resistors can be reduced, thereby allowing a further miniaturization of the printed circuit boards.\nTransformers.\nLTCC transformers are similar to LTCC inductors except transformers contain two or more windings. To improve coupling between windings transformers includes a low-permeability dielectric material printed over the windings on each layer. The monolithic nature of LTCC transformers leads to a lower height than traditional wire wound transformers. Also, the integrated core and windings mean these transformers are not prone to wire break failures in high mechanical stress environments.\nSensors.\nIntegration of thick-film passive components and 3D mechanical structures inside one module permitted the fabrication of sophisticated 3D LTCC sensors e.g. accelerometers.\nMicrosystems.\nThe possibility of the fabrication of many various passive thick-film components, sensors and 3D mechanical structures enabled the fabrication of multilayer LTCC microsystems.\nUsing HTCC technology, microsystems for harsh environments, such as working temperatures of 1000 °C, have been realized.\nApplications.\nLTCC substrates can be most beneficially used for the realization of miniaturized devices and robust substrates. LTCC technology allows the combination of individual layers with different functionalities such as high permittivity and low dielectric loss into a single multilayer laminated package and thereby to achieve multi-functionality in combination with a high integration and interconnection level. It also provides the possibility to fabricate three-dimensional, robust structures enabling in combination with thick film technology the integration of passive, electronic components, such as capacitors, resistors, and inductors into a single device.\nComparison.\nLow-temperature co-firing technology presents advantages compared to other packaging technologies including high-temperature co-firing: the ceramic is generally fired below 1,000 °C due to a special composition of the material. This permits the co-firing with highly conductive materials (silver, copper, and gold). LTCC also features the ability to embed passive elements, such as resistors, capacitors and inductors into the ceramic package, minimising the size of the completed module.\nHTCC components generally consist of multilayers of alumina or zirconia with platinum, tungsten and moly-manganese metalization. The advantages of HTCC in packaging technology includes mechanical rigidity and hermeticity, both of which are important in high-reliability and environmentally stressful applications. Another advantage is HTCC's thermal dissipation capability, which makes this a microprocessor packaging choice, especially for higher-performance processors.\nCompared to LTCC, HTCC has higher-resistance conductive layers.", "Engineering,_Manufacturing": 0.9999723434, "qwen": "Yes"}
{"id": "5561979", "revid": "45708962", "url": "https://en.wikipedia.org/wiki?curid=5561979", "title": "Duplex printing", "text": "Duplex printing is a feature of some computer printers and multi-function printers (MFPs) that allows the printing of a sheet of paper on both sides automatically. Print devices without this capability can only print on a single side of paper, sometimes called single-sided printing or simplex printing. \nConsumer and low-to-medium volume office printers use a duplexing unit that reverses a piece of paper after the first side has been printed. Duplex multifunction printers that also support duplex scanning have a \"reversing automatic document feeder\" (RADF) for scanning both sides. Higher volume printers may effectively have two print engines in a single device, and are able to print both sides of the paper in a single pass.\nOverview.\nDuplex print devices, depending on options, software, and printer settings, can print single-sided page to single-sided page (1:1) or double-sided page to double-sided page (2:2). Many can also combine single-sided pages into a double-sided page format (1:2). Double-sided booklet formats (2:2 with a center fold) are also available, depending on optional outputs from the printer.\nPrinting Formats.\nDuplexed documents can be printed to be bound on either the short edge or the long edge. This functionality is mostly available on printers that come with a duplexer. Long edge binding in portrait mode allows pages to be turned side-to-side like a book. Short-edge binding allows the pages to be oriented correctly if they are flipped vertically, as in a notepad. This second form of printing/binding is sometimes known as \"tumble.\" If the printing is done in landscape mode, these concepts are transposed since the print direction is different. \nSingle-Sided Printing.\nSingle-sided printers can print on both sides of the paper via manual removal and turning over of a stack of sheets after one side is printed on; however, the user has to manually turn the (half-done) print job over and re-invoke the printing of the document, with care to ensure that the order and orientation is correct. Printing software frequently has an option to print only odd or even pages, simplifying this process.\n'Perfecting' in Commercial Printing.\nIn commercial printing (books, magazines, newspapers, etc.), the term applied to imparting an image to both sides of the substrate at the same time is 'perfecting' and is commonly achieved—especially in lithography—by passing the substrate through a perfecting drum, thus turning the sheet over after the first side is printed. The turned sheet then continues its way through the press, being gripped at the opposite edge whilst the second side is printed. This in effect tumbles the job; therefore, accurate sheet sizing is necessary to ensure accurate backing up of the job.\nSome printers only support duplexing if an optional attachment is fitted.", "Engineering,_Manufacturing": 0.9987332225, "qwen": "Yes"}
{"id": "74107601", "revid": "39544904", "url": "https://en.wikipedia.org/wiki?curid=74107601", "title": "Planned obsolescence (disambiguation)", "text": "Planned obsolescence is the policy of deliberately manufacturing a product with a limited lifespan.\nPlanned obsolescence may also refer to:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "74141198", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=74141198", "title": "Get it Made", "text": "Get It Made is a manufacturing company based in London, UK. The company identifies as an online subcontracting platform that connects its clients with manufacturers.\nHistory.\nGet It Made was founded in 2011 by director Luke Smoothy.\nAccording to the founder, he started the company with less than one thousand British pounds of seed money.\nIts customer base is predominantly UK and Ireland based, but it also has clients in Northern Europe, Eastern Europe, Australia, and New Zealand.\nThe organisation offers a £10,000 grant to manufacturing start-ups led by people under thirty years old.\nProcess.\nThe company does not have in-house machinery; it uses the manufacturing capability of other companies to fulfil orders. The company has a small supplier base in the UK, the Czech Republic, and China.\nIts services offered include CNC machining, aluminium extrusions, aluminium die casting, lost wax casting, low-volume silicone moulding, high-volume injection moulding, stamping (pressing), fabricating, tube and wire manipulation, welding, laser cutting, and water-jet cutting.", "Engineering,_Manufacturing": 0.9999767542, "qwen": "Yes"}
{"id": "57191145", "revid": "4637213", "url": "https://en.wikipedia.org/wiki?curid=57191145", "title": "Ultrasonic welding of thermoplastics", "text": "Ultrasonic welding is a method of joining thermoplastic components by heating and subsequent melting of surfaces in contact. Mechanical vibration with frequency between 10 and 70 kHz and amplitude of 10 to 250 μm is applied to joining parts. After ultrasonic energy is turned off, the parts remain in contact under pressure for some time while the melt layer cools down creating a weld.\nDifferent join designs and process controls are used in ultrasonic welding. A sharp surface feature is typically introduced to one of the parts ensuring consistency of the welding process. Components of ultrasonic welding systems as well as the areas of application are described in the article Ultrasonic welding.\nAdvantages and disadvantages.\nFollowing advantages are typically attributed to ultrasonic welding:\nFollowing are the disadvantages of ultrasonic welding:\nProcess description.\nPlunge and continuous welding are the welding modes of thermoplastics.\nPlunge ultrasonic welding.\nWith plunge ultrasonic welding the parts are first secured in a fixture. Ultrasonic energy is then applied to create a weld. After the weld is cooled down, the parts are removed from the fixture.\nAt the start of the process, an actuator is moved to a part. This stage is called \"downstroke.\" Ultrasonic energy can be applied during this phase depending on the size of a horn used. The larger the horn the harder it is to vibrate. Therefore, application of ultrasonic energy during the down stroke becomes necessary (\"pre-triggering\"). In other cases, the vibration is applied after the horn came in contact with the part and some pressure has been created. The force is then continues to increase linearly until some predefined value.\nThe power rises at the same time as ultrasonic energy is being applied in order to accommodate the stack vibration. After some period of time a steady-state process, which indicate sufficient melting at the interface, is reached. At this point, ultrasonic energy is turned off. In production, this often happens prior to reaching the steady-state process as desired strength of the weld joint for a particular application is typically reached at this point. The tooling continues to stay on the part for a period of time called \"hold time.\" This allows for certain pressure (\"hold force\") to be applied to the part. Hold time typically lasts for one half of weld time allowing the weld to solidify.\nThe tooling is being removed from the part during a phase called “up-stroke.” This stage takes place at the completion of the hold time. Some amount of plastic substrate can remain on tooling surface after the welding process. To clean the surface, ultrasonic energy is applied when the tool is being retracted from the part (\"post weld burst\").\nContinuous ultrasonic welding.\nContinuous ultrasonic welding mode is used for joining thin layers of material and is often employed for manufacturing products for hospitals such as gowns and sterile garments, and in other applications.\nTwo layers of material are pulled through a space between a disk – rotary drum (anvil) – and a horn (image). Anvil's surface contains certain pattern. The weld is created at these asperities and the areas between the peaks remain unboned. Surface of the horn is typically round, which prevents undesirable seizing of material. Round horn also allows for proper force distribution at the contact interface.\nMore than two layers of material can be welded at once. The materials to be welded experience similar vibrations to those in plunge welding but shorter in time. Hold force to the newly welded region is provided by previously welded section that has come out of the tooling and cooled down.\nScan welding is a type of continuous ultrasonic welding in which case large plates or sheets can be welded. In scan welding, a part is secured on a stationary table and the horn moves across the part creating a weld joint. A combination of stationary horn and mobile table can also be employed. The horn has round edges as in case with continuous welding and the ultrasonic vibrations are similar to those in plunge welding. The horn can be used to provide the hold force.\nProcess control.\nDifferent ultrasonic welding machines offer different process controls. Each application determines the level of process control. In case with ordinary spot welds, a hand-held welder would be sufficient. More sophisticated equipment with computerized controls and built-in statistical process control (SPC) software may be appropriate in medical devices industry and other applications requiring narrow tolerances and high quality welds.\nFollowing modes of process control are used in ultrasonic welding:\nMost of these modes require microprocessor based controller while a basic welding system would be enough for time mode. Welding parameters can be monitored in real time with microprocessor based controllers.\nThe majority of welding systems include \"time mode\" that allows the operator to specify the duration of welding process independent from other parameters. In \"energy control mode\", the vibration of the tool continues until a preset energy level is reached. Energy mode can be used in conjunction with time mode to improve the quality of welded parts. Certain time limits can be defined to reach the necessary energy level. Should the actual time for reaching the preset energy level deviate from those time limits, such an event would be indicative of a potential issue with the weld.\nIn \"collapse mode\", ultrasonic energy is applied until the parts have collapsed (moved relative to one another) to a certain height. In addition to microprocessor based controller, a linear encoder is used in systems with collapse control. In this mode, the final height of the weld joint can also be controlled by detecting the position of the horn. In \"peak power mode\", the vibration continues until predefined power level is reached. The final dimensions of the weld joint can also be controlled with \"ground detect mode\". In this case, ultrasonic energy is applied until the horn makes electrical contact with the fixture that is positioned at the desired height.\nVarious combinations of process control modes can be employed to define an operating window and aid in quality control.\nJoint design.\nAs with other welding processes, join design is essential step in product development. Many factors should be considered in joint design such as materials to be welded, thickness of parts, operating conditions of the final product, aesthetics and others. Narrow contact area between joining parts is essential design attribute. It allows lower energy input for generating a surface layer of molten plastic. Parts fit-up should provide necessary alignment without interference with their surface features.\nEnergy directors.\n \nEnergy director is a triangular section molded on one of the joint parts. While the parts initially contact each other through this triangle, it carries the highest stress, and is therefore the first portion to melt under application of ultrasonic energy. The purpose of energy directors is to ensure that sufficient amount of material is melted as they fill out the gap between mating parts. Energy directors most commonly used with amorphous polymers, but can also be used with semi-crystalline polymers.\nWhile flash is commonly produced with such joint design, it can be covered with a flash trap. This joint feature conceals the flash providing aesthetic appearance. Minimum recommended wall thickness in this case is 2.03 – 2.29 mm. Since the smaller surface area is used to create a weld with step joint design, it could have lower strength than butt joint design.\nFollowing dimensions for energy directors are typically recommended:\nSharper apex angle provides greater weld strength and ensures tight seal. Such design also works well with polycarbonate and acrylic.\nButt joint is one of the most common weld configurations used with energy directors. Hermetic seal may not be easily achieved in semi-crystalline polymers as they crystallize faster when exposed to air atmosphere. However, hermetic seal can be obtained with amorphous polymers provided good alignment of mating parts with additional fixtures.\nTongue and groove joint design does not require additional fixtures for proper alignment. Molten plastic is fully enclosed in the groove providing aesthetic appearance. Minimum recommended wall thickness is 3.05 – 3.12 mm.\nShear joints.\nSome applications require the plastic welds to be hermetically stable. To satisfy this requirement, shear joints are typically used instead of energy directors. To achieve proper sealing, small tolerances are necessary. Such a stipulation could be difficult to satisfy with larger parts.\nWhen a shear joint is assembled, top part contacts the bottom one along a thin edge, which is the first section to melt. This molten material then flows along the side wall of the bottom part filling up the gap between the parts. While a shear joint provides alignment for mating parts, it often requires additional fixtures to support the top part of the joint from deflecting outwards as it experiences pressing force from the tool. To mitigate the risk of deflection, robust design of the top part ensuring sufficient stiffness is essential.\nShear joints can be used with all polymers. They are well-suited for cylindrical parts.", "Engineering,_Manufacturing": 0.9999927282, "qwen": "Yes"}
{"id": "2246651", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=2246651", "title": "Blow fill seal", "text": "Blow-Fill-Seal, also spelled as Blow/Fill/Seal, in this article abbreviated as BFS, is an automated manufacturing process by which plastic containers, such as bottles or ampoules are, in a continuous operation, blow-formed, filled, and sealed. It takes place in a sterile, enclosed area inside a machine, without human intervention, and thus can be used to aseptically manufacture sterile pharmaceutical or non-pharamceutical liquid/semiliquid unit-dosage forms. BFS is an advanced aseptic processing technology that is typically used for filling and packaging of certain sterile liquid formulations like liquid ophthalmics, inhalational anesthetics, or lavaging agents, but can also be used for injectables, parenteral medicines, and several other liquid or semiliquid medications, with fill volumes ranging from 0.1...1000 cm³. Compared against traditional glass ampoules, BFS ampoules are inexpensive, lightweight, and shatterproof. \nHistory.\nBFS was developed in the early 1960s at Rommelag. In 1963, Gerhard Hansen applied for a patent on the BFS process. Originally, it was used for packaging of non-sterile products, such as non-sterile medical devices, food, and cosmetics. In the early 1970s, Rommelag's Bottelpack system was first used for packing large volume pharmaceutical solutions. By the late 1980s, BFS had been well-established in the packaging industry, especially for packaging pharmaceutical and healthcare products. During the 1980s and 1990s, BFS came into use for the now common small volume unit-dosage forms. Since the early 2000s, BFS has been emerging as the preferred packaging process for parenteral products.\nBFS process.\nThe BFS process functions similarly to conventional extrusion blow molding, and takes place within a BFS machine. First, a plastic polymer resin is heated to >160 °C and compressed to 35 MPa, allowing it to be extruded in tubular form, and be taken over by an open two-part mold to form the container. Then, the mold closes which welds the bottom of the container. Simultaneously, the parison above the mold is cut, or the filling needles are placed in the parison head without the parison being cut (rotary BFS type). Next, a filling mandrel with blowing air function is placed in the neck area that seals the container. Sterile compressed air is then introduced through the filling mandrel to inflate and form the container. In the BFS process for smaller ampoules the compressed air system is avoided by using vacuum forming the container instead. After the BFS container has been formed, the desired liquid is filled into the container through the filling mandrel unit. Then, the filling mandrel unit is lifted off, and the head mold hermetically seals the container. Simultaneously, the head contour is formed by vacuum. In the last step, the mold opens and the finished container leaves the mold.\nOne process cycle takes a few seconds. The process speed and thus process output largely depends upon the BFS container size and the BFS machinery dimensioning. For instance, in the early 2000s, Rommelag's 3012, 305, and 4010 M machines had outputs of approximately 4000, 8000, or 20,000 containers per hour. These machines have been succeeded by the Rommelag 312, 321, 360, 364 and 460 machines with output ranges of up to 35,000 containers per hour.\nSterility requirements.\nThe BFS processes is an aseptic filling process, which produces sterile products and thus needs to be sterile. Aseptic BFS machines must be designed in a way that prevents extraneous contamination. Thus, rotary-type BFS machines are placed in classified areas same as shuttle-type BFS machines (open parison), which have a cleanroom shroud grade-A-compliant provided with sterilised air and kept under overpressure. Automatic SIP programs are used to sterilise the BFS equipment and this avoids human interventions. Due to automatic start up and filling processes BFS machines require no human interaction during the actual BFS process. However, certain adjustments or interventions need to be carried out by personnel. Both particle and microbiological contamination monitoring are required in a BFS machine environment, as well as routine CIP/SIP processes. BFS machines are typically fitted with several different sterilising air filtration systems for the buffer air, support parison air and air shroud grade A air (if needed for shuttle machines, e. g. open parison type ones). Typically, the air is sterilised by filtration systems that have automatic filter integrity testing installed (i. e. automatic water intrusion or particle testing). The air systems are typically integrated into the SIP cycle of the BFS machine. \nBFS material.\nThe materials used in BFS packaging are usually polyolefins, mainly polyethylene (LDPE or HDPE), and polypropylene (PP). These materials are robust and inert to ensure sterility and tightness during the product's shelf life. Diffusion tendencies can be reduced by using virgin polymers, but diffusion cannot be prevented entirely. This is due to the nature of polyolefins and their additives, if present. Several polyethylene suppliers have developed special EP or USP grade resin for BFS containers. Permeation into BFS containers and water loss may be an issue with some BFS resin. Therefore, in some applications, secondary packaging methods (laminate pouches) are used.\nAdvantages.\nBFS allows many different container designs, a consistent high process quality, a high process output, and is, compared against other packaging processes, inexpensive. In addition to that, BFS containers are lighter than glass containers, and shatterproof, which eases their transport. Due to the single-dose nature of BFS containers, they are more convenient to use for patients. BFS technology assures high levels of sterility, especially compared against conventional filling, which is mainly achieved by the absence of human contact/interventions – a major source of contamination.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "12274410", "revid": "31439127", "url": "https://en.wikipedia.org/wiki?curid=12274410", "title": "Elmos Semiconductor", "text": "Elmos Semiconductor SE is a German manufacturer of semiconductor products headquartered in Dortmund, North Rhine-Westphalia, Germany. \nElmos supplies automotive application-specific integrated circuits (ASICs).\nSilicon Microstructures.\nSilicon Microstructures, Inc.(SMI) was founded in 1991 as a commercial source of high-performance silicon pressure sensors, including Microelectromechanical systems sensors, and accelerometers. Its first product was a silicon sensor for very low-pressure usage. SMI was acquired in March 2001 from OSI Systems.\nSMI began production on higher performance, system level sensors and microstructures, wireless, RF and bus addressable microstructures.\nIn August 2002, SMI acquired the IC Sensors' wafer fabrication operations and wafer R&D group and relocated to Milpitas, California. The following year, Silicon Microstructures undertook a significant and complete wafer fabrication upgrade to expand the facility for full 6\" wafer handling.\nThis facility processed primarily 6 inch wafers and has advanced technical capabilities including deep reactive ion etching (DRIE) and plasma enhanced fusion bonding.", "Engineering,_Manufacturing": 0.9998784065, "qwen": "Yes"}
{"id": "26551186", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=26551186", "title": "Tetrapolar plug", "text": "A standard tetrapolar telephone plug in electronics and telecommunications, has four round metal pins and one plastic pin. The design is only used in Belgium for telephone wiring. It is similar to the tripolar telephone plug of Italy and also the Swedish telephone plug.\nThe plastic pin adds a presence function. When not inserted into a jack, the jack itself (mechanically) connects the incoming line to the next socket. The article on the Swedish telephone plug details its functional principles.", "Engineering,_Manufacturing": 0.9984866977, "qwen": "Yes"}
{"id": "36685710", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=36685710", "title": "Bar puller", "text": "A bar puller is a tool for automatically drawing in material (round tubes or solid bars) on a CNC lathe. The machined part is cut off and new material has to be fed into the machine.\nFunction.\nBar pullers are used in CNC lathes to automatically draw in bars from the clamping chuck. In this case they serve as a substitute for a bar feeder on an NC/CNC lathe.\nThe clamping chuck is fitted directly into the turret of the lathe or into the bar holder. There are two different versions, depending on the design: Start on the X-axis (starting from the radius) or start on the Z-axis (direction of the spindle).\nA bar feeder magazine and workpiece stop are not required when a bar puller is used.\nMaterial.\nThe housing can be made of aluminium or steel, the top jaws are made of case-hardened steel, tempered steel and burnished.\nHistory.\nThe history of the bar puller begins with the introduction of the NC/CNC lathes in around 1980. At this time lathes were changed to permit inexpensive and economical production of small or medium-sized batches.\nThe bar puller serves to draw bars into the lathe without operators having to feed the machine with material each time it is required. With the introduction of CNC (Computerized Numerical Control) for the lathes it was possible to ensure the reliability of the individual process operations (moving the turret to the material, opening the clamping chuck, drawing in the material, closing the clamping chuck, moving the turret away with the bar puller).", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "2637701", "revid": "42060178", "url": "https://en.wikipedia.org/wiki?curid=2637701", "title": "End mill", "text": "An end mill is a type of milling cutter, a cutting tool used in industrial milling applications. It is distinguished from the drill bit in its application, geometry, and manufacture. While a drill bit can only cut in the axial direction, most milling bits can cut in the radial direction. Not all mills can cut axially; those designed to cut axially are known as end mills.\nEnd mills are used in milling applications such as profile milling, tracer milling, face milling, and plunging.\nTypes.\nSeveral broad categories of end- and face-milling tools exist, such as center-cutting versus non-center-cutting (whether the mill can take plunging cuts); and categorization by number of flutes; by helix angle; by material; and by coating material. Each category may be further divided by specific application and special geometry.\nA very popular helix angle, especially for general cutting of metal materials, is 30°. For finishing end mills, it is common to see more tight spiral, with helix angles 45° or 60°. Straight flute end mills (helix angle 0°) are used in special applications, like milling plastics or composites of epoxy and glass. Straight flute end mills were also used historically for metal cutting before invention of helical flute end mill by Carl A. Bergstrom of Weldon Tool Company in 1918.\nThere exist end mills with variable flute helix or pseudo-random helix angle, and discontinuous flute geometries, to help break material into smaller pieces while cutting (improving chip evacuation and reducing risk of jamming) and reduce tool engagement on big cuts. Some modern designs also include small features like the corner chamfer and chipbreaker. While more expensive, due to more complex design and manufacturing process, such end mills can last longer due to less wear and improve productivity in high speed machining (HSM) applications.\nIt is becoming increasingly common for traditional solid end mills to be replaced by more cost-effective inserted cutting tools (which, though more expensive initially, reduce tool-change times and allow for the easy replacement of worn or broken cutting edges rather than the entire tool). Another advantage of indexable end mills(another term for tools with inserts) is their ability to be flexible with what materials they can work on, rather than being specialized for a certain material type like more traditional end mills. For the time being however, this only generally applies to larger diameter end mills, at or above 3/4 of an inch. These end mills are generally used for roughing operation, whereas traditional end mills are still used for finishing and work where a smaller diameter, or a tighter tolerance, are required; modular tooling introduces additional margins of error that can compound with each new component, whereas a solid tool can provide a smaller tolerance range for the same price level.\nEnd mills are sold in both imperial and metric shank and cutting diameters. In the USA, metric is readily available, but it is only used in some machine shops and not others; in Canada, due to the country's proximity to the US, much the same is true. In Asia and Europe, metric diameters are standard.\nGeometry.\nA variety of grooves, slots, and pockets in the work-piece may be produced from a variety of tool bits. Common tool bit types are: square end cutters, ball end cutters, t-slot cutters, and shell mills. Square end cutters can mill square slots, pockets, and edges. Ball end cutters mill radiused slots or fillets. T-slot cutters mill exactly that: T-shaped slots. Shell end cutters are used for large flat surfaces and for angle cuts. There are variations of these tool types as well.\nThere are four critical angles of each cutting tool: end cutting edge angle, axial relief angle, radial relief angle, and radial rake angle.\nDepending on the material being milled, and what task should be performed, different tool types and geometry may be used. For instance, when milling a material like aluminum, it may be advantageous to use a tool with very deep, polished flutes, a very sharp cutting edge and high rake angles. When machining a tough material such as stainless steel, however, shallow flutes and a squared-off cutting edge will optimize material removal and tool life.\nA wide variety of materials are used to produce the cutting tools. Carbide inserts are the most common because they are good for high production milling. High speed steel is commonly used when a special tool shape is needed, not usually used for high production processes. Ceramics inserts are typically used in high speed machining with high production. Diamond inserts are typically used on products that require tight tolerances, typically consisting of high surface qualities (nonferrous or non-metallic materials).\nIn the early 90s, use of coatings became more common. Coatings can provide various benefits including wear resistance, reduction of friction to assist with chip evacuation, and increased heat resistance. Most of these coatings are referred to by their chemical composition.\nThough PCD veins is not a coating, some end mills are manufactured with a 'vein' of polycrystalline diamond. The vein is formed in a high temperature-high pressure environment. The vein is formed in a blank and then the material is ground out along the vein to form the cutting edge. Although the tools can be very costly, they can last many times longer than other tooling.\nAdvances in end mill coatings are being made, however, with coatings such as Amorphous Diamond and nanocomposite PVD coatings beginning to be seen at high-end shops (as of 2004).\nAlthough coatings have a typical color, manufacturers may modify the coating process or add additives to change the appearance without affecting the performance as part of their branding. Bright blues, reds and turquoise are among the \"unnatural\" colors.\nEnd mills are typically made on CNC (computer numeric controlled) tool and cutter grinder machines under high-pressure lubricants such as water, water-soluble oil, and high-flashpoint oil. Grinding inside the machine is accomplished with abrasive wheels mounted on a spindle (and in some cases, multiple spindles). Depending on what material is being ground, these wheels are made with industrial diamond (when grinding tungsten carbide), cubic boron nitride (when grinding cobalt steel), and other materials (when grinding, for instance, ceramics), set in a bond (sometimes copper).\nFlute types.\nSingle: Is used to remove lots of material at a very fast rate. Traditionally used in a roughing operation.\n2 Flute: Allows for more chips to be removed from the part. Primarily used in slotting and pocketing operations in non-ferrous materials.\n3 Flute: Similar to the 2 Flute end mill but can be used to cut ferrous and non-ferrous materials\n4+ Flute: Designed to run at faster feed rates but due to having more flutes it causes issues with chip removal.\nOperations.\nRoughing: the purpose is to remove a big chunk of material from workpieces, sometimes to get rid of excess material in order to get closer to the final shape. It attempts to get really close to the finalized shape. Traditionally it's the first major operation in the machining process. \nContouring/Profiling: this is a process used to mill different surfaces such as flat or irregular ones. This type of process can be done during the roughing or finishing phase of the overall operation. \nFacing: is an operation used to face the part down to specified dimension. Facing can be done using end mills or a special face mill.\nPocketing/Slotting: this is a process to make a pocket on the inside of the part. A pocket can be shallow or deep, depending on specs. ", "Engineering,_Manufacturing": 0.9999792576, "qwen": "Yes"}
{"id": "2644490", "revid": "1061253791", "url": "https://en.wikipedia.org/wiki?curid=2644490", "title": "Thickness planer", "text": "A thickness planer (also known in the UK and Australia as a thicknesser or in North America as a planer) is a woodworking machine to trim boards to a consistent thickness throughout their length. \nThis machine transcribes the desired thickness using the downside as a reference / index. So, to produce a completely straight planed board requires that the down surface is straight before planing. Obtaining the first flat side requires either face planing with a jointer or face planing using a planer and jointer sled.\nFunction.\nA thickness planer is a woodworking machine to trim boards to a consistent thickness throughout their length and flat on both surfaces.\nIt is different from a surface planer, or jointer, where the cutter head is set into the bed surface. A surface planer has slight advantages for producing the first flat surface and may be able to do so in a single pass. However the thicknesser has more important advantages in that it can produce a board with a consistent thickness, avoids producing a tapered board, and by making passes on each side and turning the board, may also be used for the initial preparation of an unplaned board.\nDesign.\nA thickness planer consists of three elements: a cutter head which contains the cutting knives; a set of rollers which draw the board through the machine; and a table which is adjustable relative to the cutter head to control the resultant thickness of the board. Some portable thickness planers differ slightly in that the table is fixed and the cutter head/feed roller assembly is adjusted.\nIndustrial thickness planers are capable of accepting very wide boards and removing large amounts of material in a single pass. These machines are driven by powerful motors and are of very heavy construction. In recent times, a range of lightweight portable thickness planers have become available which use the cheaper, but noisy, universal motors rather than induction motors and are much less expensive than industrial versions.\nIn Europe, the functions of the jointer and thickness planer are often combined into a single combination machine, a jointer-planer. In the U.K. this is called a \"planer–thicknesser\" or \"over–and–under\".\nOperation.\nIn operation, the table is set to the desired height and then the machine is switched on. The board is fed into the machine until it makes contact with the in-feed roller which grips the board and draws it into the machine and past the rotating cutter head. The knives remove material on the way through and the out-feed roller pulls the board through and ejects it from the machine at the end of the pass.\nTo finish a board that is flat and of uniform thickness along its length, it is necessary to start with a board that has at least one perfectly flat reference face. The board is fed with this reference face flat on the table and the cutter head removes an amount of material from the opposite face so that it is made parallel to the reference face. The reference face is often created by first passing the board over a jointer. If the lower face is not flat, the feed roller pressure pressing the board against the table will deform the board, which will then spring back as it leaves the machine, resulting in a non-flat upper surface.\nOne problem often encountered when using a thickness planer is snipe. This manifests as a deeper cut on a short section of the board at either end and is caused by incorrect feeding or misalignment of the in-feed or out-feed tables, or an unnecessarily high setting of the rollers recessed in the surface of the in-feed table. It can be accommodated by keeping the board overlong to allow later trimming.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "43013627", "revid": "10289486", "url": "https://en.wikipedia.org/wiki?curid=43013627", "title": "Conformal cooling channel", "text": "Conformal cooling channel is a cooling passageway which follows the shape or profile of the mould core or cavity to perform rapid uniform cooling process for injection moulding or blow moulding processes.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "43017519", "revid": "1054917774", "url": "https://en.wikipedia.org/wiki?curid=43017519", "title": "Direct clustering algorithm", "text": "Direct clustering algorithm (DCA) is a methodology for identification of cellular manufacturing structure within an existing manufacturing shop. The DCA was introduced in 1982 by H.M. Chan and D.A. Milner The algorithm restructures the existing machine / component (product) matrix of a shop by switching the rows and columns in such a way that a resulting matrix shows component families (groups) with corresponding machine groups. See Group technology. The algorithm is executable in manual way but was already suitable for computer use of the time.\nProcedure.\nThe cellular manufacturing structure consists of several machine groups (production cells) where corresponding product groups (products with similar technology) are being exclusively manufactured. In aim of identification of possible cellular manufacturing structure within an existing manufacturing shop the DCA methodology roughly provides following procedure:\nThe experience.\nThe DCA methodology would give a perfect result in an ideal case where there are no overlapping machines or products between the groups. The overlapping in most real cases represents further challenge for the methodology users. The \"Formation of Machine Cells/ Part Families in Cellular Manufacturing Systems Using an ART-Modified Single Linkage Clustering Approach – A Comparative Study\" by M. Murugan and V. Selladurai shows the comparison of DCA to some other methodologies of the same purpose.", "Engineering,_Manufacturing": 0.999990344, "qwen": "Yes"}
{"id": "31301051", "revid": "1158185546", "url": "https://en.wikipedia.org/wiki?curid=31301051", "title": "2-4-6-2", "text": "A 2-4-6-2 steam locomotive, in the Whyte notation for describing locomotive wheel arrangements, has a two-wheel leading truck, one set of four driving wheels, one set of six driving wheels, and a two-wheel trailing truck.\nOther equivalent classifications are:\nUIC classification: 1BC1 (also known as German classification and Italian classification)\nFrench classification: 1231\nThis most unusual wheel arrangement was only ever used on a duplex locomotive type.", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "25428875", "revid": "45363739", "url": "https://en.wikipedia.org/wiki?curid=25428875", "title": "Saki Corporation", "text": " is a Japanese company established in 1994 that manufactures high-speed automated optical inspection (AOI) and solder paste inspection (SPI) systems for the electronics assembly markets. Saki Corporation has headquarters in Tokyo, Japan with offices and sales and support centers on the world.\nSaki Corporation has Quality Management System JIS Q 9001:2008 and certifications. The company's CEO is Koike Norihiro.\nAOI.\nReferences", "Engineering,_Manufacturing": 0.9999938011, "qwen": "Yes"}
{"id": "25431209", "revid": "32421905", "url": "https://en.wikipedia.org/wiki?curid=25431209", "title": "Z-pinning", "text": "Z-pinning is a technique to insert reinforcing fibres (also called Z-pins or Z-fibres) along the Z-direction of continuous fibre-reinforced plastics. Z-pins can be made of metal or precured unidirectional composite fibres. It is designed for use within pre-preg technology; there is extensive experimental evidence that Z-pinning dramatically improves the resistance of the composite structure to delamination. The figure on the right shows a Z-pin inserted in between the fibres of the material.  The pin spreads the fibres and creates an oval shaped gap that is filled with resin. The Z-pin prevents the composite from delamination.  When a load is applied the cracks will typically form along the line of the opening.\nBenefits.\nZ-pinning is a versatile technique that can be applied to many materials that will benefit from added strength and durability. They are especially effective when used in materials that are subject to delamination, because the Z-pins can counteract this problem. Z-pinning has been used in aircraft manufacturing to add strength.  By Z-pinning the materials on an aircraft, such as the wings, it can have a much higher resistance to damage during flight.  Also, if the aircraft does suffer from a minor crack, the Z-pinning will prevent it from catastrophic failure.  Z-pins can also be used for automotive applications. The pins can be inserted into carbon fibre parts to increase the strength of them.  If the front splitter of a car was constructed with Z-pins, it would be able to withstand significantly more impacts because the Z-pins would hold it together even with a minor crack. This allows the carbon fibre parts to remain light while still being strong. Testing of different size Z-pins has indicated that larger pins lead to an increase in strength. A 1% increase in the size of the Z-pin increases toughness by up to 6 to 25 times. However, too large of a pin can disrupts the fibres of the material more leading to it fracturing.\nZ-Pin production.\nThere are many methods of creating Z-pins.  Typically, Z-pins are pre-cured and then inserted into composites. One process consists of pulling a continuous-fibre tow through a bath of liquid resin using a pultrusion machine.  The fibre is then pulled out of the bath through the die which creates the shape and size of the pin.  The pin is next sandwiched in a vertical orientation in foam to finish the process.  The pin may be coated or treated as an additional step depending on the application. This process is one of the more efficient and cost effective ways of producing Z-pins because it can be easily adapted to different pin sizes.\nManufacturing with Z-Pins.\nZ-pins have many ways of being inserted into the material of choice. The most common method is a process using an ultrasonic hammer.  The hammer compresses the foam that encases the pins and pushes the pins into the material. The hammer induces high frequency vibrations to the pin as it compresses. The vibrating chamfered tip of the Z-pins locally heats up and softens the resin allowing the Z-fibre to penetrate the preform with minimal disruption of the long fibres. The remaining pin and laminate above the surface are removed to create a smooth and even surface The surface can be finished with a coating to seal the Z-pins inside the material. A hand-held ultrasonic gun can also be used to insert Z-pins on a small scale production. This is ideal for testing materials containing Z-pins because they can be easily inserted into any location on the material.", "Engineering,_Manufacturing": 0.9999856949, "qwen": "Yes"}
{"id": "25446774", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=25446774", "title": "Velostat", "text": "Velostat, also known as Linqstat, is a packaging material made of a polymeric foil (polyolefins) impregnated with carbon black to make it somewhat electrically conductive. It is used for the protection of items or devices that are susceptible to damage from electrostatic discharge. It was developed by Custom Materials, now part of 3M. Velostat is a U.S. registered trademark (4,964,564) of Desco Industries Inc. Desco Industries purchased the assets of the 3M Static Control business on January 2, 2015.\nVelostat is piezoresistive; its resistance changes with flexing or pressure. For instance, 25 mm² of fresh Velostat sandwiched between two electrodes measures around 9 kΩ without any force applied. But with 3 Newtons of force applied, its resistance drops to 1 kΩ. For material that has been used, those resistances are roughly halved.\nVelostat's low cost and piezoresistive properties have made it popular for making inexpensive flex or pressure sensors for microcontrollers. One example is shoes which light up when the wearer steps. Since Velostat's resistance is reduced when pressure is applied, a voltage divider measuring that resistance can indicate when weight is applied or removed from the shoes.", "Engineering,_Manufacturing": 0.9985983968, "qwen": "Yes"}
{"id": "40400006", "revid": "1151060829", "url": "https://en.wikipedia.org/wiki?curid=40400006", "title": "Air bearing", "text": "Air bearings (also known as aerostatic or aerodynamic bearings) are bearings that use a thin film of pressurized gas to provide a low friction load-bearing interface between surfaces. The two surfaces do not touch, thus avoiding the traditional bearing-related problems of friction, wear, particulates, and lubricant handling, and offer distinct advantages in precision positioning, such as lacking backlash and static friction, as well as in high-speed applications. Space craft simulators now most often use air bearings and 3-D printers are now used to make air-bearing-based attitude simulators for CubeSat satellites.\nA differentiation is made between aerodynamic bearings, which establish the air cushion through the relative motion between static and moving parts, and aerostatic bearings, in which the pressure is being externally inserted.\nGas bearings are mainly used in precision machinery tools (measuring and processing machines) and high-speed machines (spindle, small-scale turbomachinery, precision gyroscopes).\nGas bearing types.\nGas-lubricated bearings are classified in two groups, depending on the source of pressurization of the gas film providing the load-carrying capacity:\nHybrid bearings combining the two families also exist. In such cases, a bearing is typically fed with externally-compressed gas at low speed and then relies partially or entirely on the self-pressurizing effect at higher speeds.\nAmong these two technological categories, gas bearings are classified depending on the kind of linkage they realize:\nThe main air bearing types fall under the following categories:\nAerostatic bearings.\nPressurized gas acts as a lubricant in the gap between bearing moving parts. The gas cushion carries the load without any contact between the moving parts. Normally, the compressed gas is supplied by a compressor. A key goal of supplying the gas pressure in the gap is that the stiffness and damping of the gas cushion reaches the highest possible level. In addition, gas consumption and uniformity of gas supply into the gap are crucial for the behaviors of aerostatic bearings.\nDelivery of gas to the gap.\nSupplying gas to the interface between moving elements of an aerostatic bearing can be achieved in a few different methods:\nThere is no single best approach to feeding the film. All methods have their advantages and disadvantages specific to each application.\nDead volume.\nDead volumes refer in particular to chambers and canals existing in conventional aerostatic bearings in order to distribute the gas and increase the compressed pressure within the gap. The cavity inside porous (sintered) gas bearings are also attributed to dead volume.\nConventional aerostatic bearings.\nWith conventional single nozzle aerostatic bearings, the compressed air flows through a few relatively large nozzles (diameter 0.1 – 0.5 mm) into the bearing gap. The gas consumption thus allows only some flexibility such that the bearing's features (force, moments, bearing surface, bearing gap height, damping) can be adjusted only insufficiently. However, in order to allow a uniform gas pressure even with only some nozzles, aerostatic bearing manufacturers take constructive techniques. In doing so, these bearings cause dead volumes (non-compressible and thus weak air volume). In effect, this dead volume is very harmful for the gas bearing's dynamic and causes self-excited vibrations.\nSingle-nozzle aerostatic bearings.\nThe pre-pressured chamber consists of a chamber around the centralized nozzle. Usually, this chamber's ratio is between 3% and 20% of the bearing's surface. Even with a chamber depth of 1/100 mm, the dead volume is very high. In the worst cases, these air bearings consist of a concave bearing surface instead of a chamber. Disadvantages of these air bearings include a very poor tilt stiffness.\nGas bearings with channels and chambers.\nTypically, conventional aerostatic bearings are implemented with chambers and canals. This design assumes that with a limited amount of nozzles, the dead volume should decrease while distributing the gas within the gap uniformly. Most constructive ideas refer to special canal structures. Since the late 1980s, aerostatic bearings with micro canal structures without chambers are manufactured. However, this technique also has to manage problems with dead volume. With an increasing gap height, the micro canal's load and stiffness decreases. As in the case of high-speed linear drives or high-frequency spindles, this may cause serious disadvantages.\nLaser drilled Micro-nozzle aerostatic bearings.\nLaser-drilled micro nozzle aerostatic bearings make use of computerized manufacturing and design techniques to optimize performance and efficiency. This technology allows manufacturers more flexibility in manufacturing. In turn this allows a larger design envelope in which to optimize their designs for a given application. In many cases engineers can create air bearings that approach the theoretical limit of performance.\nRather than a few large nozzles, aerostatic bearings with many micro nozzles avoid dynamically disadvantageous dead volumes. Dead volumes refer to all cavities in which gas cannot be compressed during decrease of the gap. These appear as weak gas pressure stimulates vibration. Examples of the benefits are: linear drives with accelerations of more than 1,000 m/s² (100 g), or impact drives with even more than 100,000 m/s² (10,000 g) due to high damping in combination with dynamic stiffness; sub-nanometer movements due to lowest noise-induced errors; and seal-free transmission of gas or vacuum for rotary and linear drives via the gap due to guided air supply.\nMicro-nozzle aerostatic bearings achieve an effective, nearly perfect pressure distribution within the gap with a large number of micro nozzles. Their typical diameter is between 0.02 mm and 0.06 mm. The narrowest cross-section of these nozzles lies exactly at the bearing's surface. Thereby the technology avoids a dead volume on the supporting air bearing's surface and within the area of the air supplying nozzles.\nThe micro nozzles are automatically drilled with a laser beam that provides top-quality and repeatability. The physical behaviors of the air bearings prove to have a low variation for large as well as for small production volumes. In contrast to conventional bearings, with this technique the air bearings require no manual or costly manufacturing.\nThe advantages of the micro-nozzle air bearing technology include:\nSome of these advantages, such as the high flexibility, the excellent static and dynamic properties in combination, and a low noise excitation, prove to be unique among all other aerostatic bearings.\nVarious designs.\nStandard air bearings are offered with various mountings to link them in a system:\nTheoretical modeling.\nGas-lubricated bearings are usually modeled using the Reynolds equation to describe the evolution of pressure in the thin film domain. Unlike liquid-lubricated bearings, the gas lubricant has to be considered as compressible, leading to a non-linear differential equation to be solved.\nNumerical methods such as Finite difference method or Finite element method are common for the discretization and the resolution of the equation, accounting for the boundary conditions associated to each bearing geometry (linear-motion, journal and thrust bearings). In most cases, the gas film can be considered as isothermal and respecting the ideal gas law, leading to a simplification of the Reynolds equation.\nExamples.\nAutomotive technology.\nEven for movements which cause damage due to disruptive wear with roller bearings, lifetimes of the drive systems are unlimited.\nIn order to provide confidence and for the first investigations, an initial conversion from a conventional oil-guided turbo charger into air-guided was done. For a real future version, the use of results obtained from high-temperature solutions, mass products (proved production costs) and high-frequency spindles (know-how of dynamic background) will be very helpful.\nSemiconductor technology.\nIn terms of the measurement of wafers and flat panels, it is very important to place the sensor chip precisely and without any contact along the surface. Therefore, the chip is integrated directly into the bearing's surface. The maximum distance tolerance to the surface which refers to the gap variation of the air bearing, is smaller than 0.5 μm. When placing the air bearing with the sensor chip, they must not touch the wafer surface being measured. As for the up-and-down movement, a pneumatic piston is used which is, for repeatability reasons, also air-guided. The preload of the air bearing and thus the gap height are also adjusted with this piston.\nFor the electrical testing of wafers the chuck can be lifted stick-slip-free up to 3 mm. The needed contact force for the probe is adjustable and independent from stroke. The lift drive is based on a voice coil motor; the guidance is air-guided. An air-guided pneumatic piston between the chuck and the drive limits the contact force.\nLinear drives.\nThe filigree structure enables through light measurements for the 300 nm chip production with the utmost precision of less than 1 nm. In particular, the air bearings are designed for lowest air consumption with the highest stiffness.\nThe High-accelerated Doppler drive supports and guides a carbon fiber mirror (surface 500 mm x 250 mm) with an acceleration of up to 300 m/s² and a flexible movement profile with high precision. The solution consists of an air-guided drive: The beam (length 900 mm), which is fixed at the mirror, is manufactured of carbon fibre and carries the magnets of the linear motors. Cables/tubes (motor, air bearing, measurement system) do not move in order to avoid breakages due to high load cycles. The air-bearings are absolutely insensitive against geometric fluctuation as a result of a temperature change.\nBeside the performance, the reliability is extremely important for a production machine. The air-guided solution is designed to be statically determined. The iron-core linear motor and piston bearings achieve the preload for the air bearings. Thereby, the drive is easy to assemble and insensitive against geometric variations, for instance through temperature influences or the disposition of the machines.\nMedical technology.\nFat- and oil-free drives for respirators, stick-slip-free movements of scanners or a high rotary speed of large rotors have all been achieved with air bearings.\nHigh rotary speed (> 5.5 Hz / 330 rpm), low operation costs, no noise, large inner rotor diameter (> 1 m), small weight of rotor and frame, tilt possibility of the rotor as well as a high reliability. Besides a direct drive, a belt drive is also possible.\nProduction technology.\nPrimarily, stick-slip-free movements and/or smallest forces are required. The air bearing technology is predestinated for fat/oil-free high-dynamic movements with short strokes.\nWith air-guided units, optical components can be arranged to have the same diameter on a rotary table. The air bearing with vacuum preload and a constant bearing gap height floats contact-less on top of the rotary table.\nThe linear slider, which is air-guided and statically determined, guarantees a high-precision positioning of the optical component before grinding. The self-aligning process is done without friction or force. When clamped the component retains its position for further manufacturing in the sub-micrometer-range.\nSpace technology.\nWhen transporting solar panels for satellites in a launching rocket, these must be folded. After reaching orbit, they unfold via a spring mechanism, weightlessly and without friction. This process requires prior testing on Earth due to reliability reasons. During the testing design, the solar panels are hung on magnetic preloaded air-bearings that compensate for gravity. In doing so, the unfolding movement process is carried out with a minimum friction impact which means that the solar panels are tested at close to reality. Moreover, the design offers absolutely maintenance-free handling with equal sequential movements.\nThe air-bearing components (diameter 34 mm) with integrated magnets are so small such that they are able to glide contact-free along conventional rolled sheet plates smoothly and with a bearing gap height of about 25 μm. The holding force of an air bearing for one solar panel averages 600 N. This force is achieved by an equal distribution of the load on 16 single air bearing elements. The unfolding process of the solar panels has been developed for an area of 21 m x 2.5 m.\nThe permanent magnetic preloaded air-bearing guidance system may be used for many types of hanging transportation movements as well as for many other applications, such as for instance for the stick-slip-free positioning of components during assembly.", "Engineering,_Manufacturing": 1.0000063181, "qwen": "Yes"}
{"id": "16043444", "revid": "13791031", "url": "https://en.wikipedia.org/wiki?curid=16043444", "title": "Ras Al Khor Industrial Area", "text": "Ras Al Khor Industrial Area  is a locality in Dubai, the United Arab Emirates. Literally meaning \"Cape of the Creek\", Ras Al Khor is part of several industrial areas (such as Al Aweer) located in the suburban areas of Dubai. The Ras Al Khor Industrial Area comprises three sub-localities:\nThis area has automobile spare parts sales shops, Automobile service centers, Car wash/clinic, and vehicle repair. There are no more business or companies in the Ras Al Khor industrial Areas. All companies are related to the Auto mobile service/clinic/workshop/spare parts. This industrial area has a few warehouses.", "Engineering,_Manufacturing": 0.9999700785, "qwen": "Yes"}
{"id": "42600058", "revid": "1095111817", "url": "https://en.wikipedia.org/wiki?curid=42600058", "title": "Die forming (plastics)", "text": "A \"die\" in polymer processing is a metal restrictor or channel capable of providing a constant cross sectional profile to a stream of liquid polymer. This allows for continuous processing of shapes such as sheets, films, pipes, rods, and other more complex profiles. This is a continuous process, allowing for constant production (assuming constant supply of polymer melt), as opposed to a sequential (non-constant) process such as injection molding.\nProcess.\nDie forming typically occurs immediately after polymer melt has exited an extruder. The most basic process involves guiding the stream of molten polymer under pressure through a die, which three distinct regions: manifold, approach, and lip. The 'manifold' serves to channel the polymer melt from its initial extrusion point to a near-net-shape of the final product. The 'approach' region further guides the melt into the final shape, and begins to correct for any non-uniform flow. Finally, the 'lip' forms the melt into the final desired cross section and compensates for any remaining flow asymmetry. After exiting the lip of the die, the polymer melt will undergo die swell before curing. Die swell is an expansion of the melt as the pressure is released, and is dependent on polymer chemistry and die design. After curing, the solid, continuous part is drawn onto a take-up roller or cut into transportable lengths, depending on the type of part. This process may vary significantly depending on the type of die and extrusion process.\nSheet/film extrusion.\nThere are two major types of dies used in flat sheet extrusion: T-shaped and coat-hanger. A T-shaped die consists of two arms extending at right angles from the initial extrusion channel; these arms have a small slit along their length to allow the polymer melt to flow through. The melt is then further thinned by a short, flat approach before being pushed through the lips of the die. This setup can cause non-uniform flow across the width of the extruded sheet, with the melt at the center flowing faster than the melt at the edges of the die, resulting in buckling and other defects after exiting the die.\nA more modern design is the coat-hanger die. This die differs from the T-shaped die in that the arms are not at right angles to the input direction; instead, the arms are at a shallower angle and are often curved. The arms also have a variable diameter, tapering down to a smaller radius further from the input channel. The approach portion of coat-hanger dies are longer than their T-shaped counterparts, further reducing any flow nonuniformity. Finally, the melt is extruded through lips as in the T-shaped die. \nFor products such as plastic sheets or films, cooling is achieved by pulling through a set of cooling rolls (also known as calender or chill rolls), usually 3 or 4 in number. In sheet extrusion, these rolls not only deliver the necessary cooling but also help determine sheet thickness and surface texture (in case of structured rolls; i.e. smooth, levant, haircell, etc.). A common processing defect known as nerve may occur when contact time between the rollers and extrudate is too brief, resulting in insufficient cooling time.\nCoextrusion is common in sheet and film extrusion, allowing for speedy production of multi-layered parts. This is accomplished by joining multiple polymer melts in either the manifold or approach stage. Layers of different thicknesses may be formed by introducing melts at different flow rates or different manifold sizes.\nBlown film extrusion.\nThe manufacture of plastic film for products such as shopping bags and continuous sheeting is achieved using a blown film line. Polymer melt from an extruder is fed through an upright die with an annular opening. There are several types of dies that can be used, depending on final requirements of film quality and characteristics of the polymer melt: spider, crosshead, and spiral dies.\nA spider die consists of an internal mandrel connected to the outer die wall by several \"legs\", and is a moderately complex design. The resulting film will feature weld lines wherever legs were present. These weld lines are weaker than the surrounding polymer, and may also have different optical characteristics, such as haze. This weakness is caused by incomplete healing of the polymer molecular matrix. Furthermore, a pressure gradient produced by the spider legs will cause nonuniform die swell, resulting in nonuniform film thickness.\nA crosshead die splits the melt flow in two at the manifold inlet, recombining them at the opposite side of a cylindrical center mandrel. This relatively simple design results in non-symmetrical flow, as molecules take longer to reach the opposite side than the close side of the mandrel. As such, the resulting film will not be of uniform thickness. To reduce this nonuniformity, inlet diameters can be varied, and various inserts can be added to minimize stagnant regions.\nA spiral die is the most complex of the three major blown film die types. The polymer melt is evenly distributed into several feed tubes, which wind around a central mandrel. Each of these feed tubes is connected to the space between the mandrel and outer die walls; the feed tubes gradually diminish in diameter as they spiral around the mandrel. At the same time, the space between the mandrel and outer die walls is increased. This allows the polymer melt to layer and blend, resulting in a uniform melt profile free of weld lines. This die design produces the most uniform films, but is also the most expensive.\nAir pressure is introduced through the extrusion die so that after the polymer melt leaves the lip of the die, it expands in circumference. The tubing is also drawn along its length faster than it is being extruded. This leads to thinning of the film as it is expanded in both the draw (or machine) direction, and in the transverse (or hoop) direction. The ratio of the blown diameter to the extruded diameter is known as the blow-up ratio, and affects the resulting physical properties of the film, such as stiffness and strength. Film thickness and blow-up ratio can be varied by altering the take-up rate of the rollers, the internal pressure in the blown tube, and the melt extrusion rate. \nAs the film is drawn upwards, it is cooled by a ring of air blowers so that the melt first becomes an amorphous viscoelastic solid, and then a semicrystalline solid, at what is known as the frost line. After solidification, the blown film tube continues to be cooled as it is pulled up by several sets of rollers, deflating the film to form lay-flat tubing. The flat film is then wound on a spool before further processing or shipping. The height of the film line is often 10 times the diameter of the blown tube or more; film lines in excess of 30 meters are possible.\nOnce the film tube is completely cooled, it is taken up by several nip rollers. The width of the resulting doubled-over flat film is equal to half of the blown tube's circumference. The film is then either spooled as a flattened tube, or immediately split into two separate pieces. At this point, the film is ready for further processing, such as printing or cutting into final shape.\nOverjacketing extrusion.\nOverjacketing extrusion is a coating process, in which individual bare wires or bundles of pre-coated wires are coated with a layer of insulating polymer. A wide variety of materials may be used, depending on the specific application. For many applications, such as insulated cables, the polymer should be a good insulator, flexible, and wear resistant.\nIn this process, a wire (or bundle of wires) is preheated to above the glass transition or melting temperature of the polymer coating that is to be applied. This is to ensure adhesion of the new coating. Next, this preheated bare wire is pulled through a die which places a thin coating of polymer around the wire. Due to the geometry of the dies used, relatively high extrusion rates are possible while still avoiding melt fracture. The newly coated wire is then drawn through an air or gas flame to smooth the surface of the coating, and finally a water bath to fully cool the coated wire. Coated wires are now spooled to prepare for further processing, if desired.\nThere are two major types of dies used in overjacketing extrusion, both based on an overall crosshead design. Regardless of die type used, the polymer melt is often extruded at a rate less than the speed of the bare wire that is drawn through the die, typically on the order of 1-4 times the speed of the melt. This causes the polymer jacket to extend, thin, and tighten around the central wire, increasing adhesion of the new layer.\nThe first dye type is an annular, or tubing/jacketing, die that extrudes a tube of polymer that is initially \"not\" touching the bare wire. A vacuum is then applied to the still-molten polymer tube, causing it to be drawn onto and bond to the surface of the bare wire. This type of die is typically used to coat very thin wires with polymer jacketing that is highly viscous.\nThe second die type, known as a pressure type die, relies on contact between the jacketing polymer and bare wire inside the die. In this die type, a ring of polymer melt under pressure is forced around the bare wire. Due to the applied pressure of the melt, the opening around the inlet for the bare wire must be very small, on the order of 0.05 mm. The size of the exit opening controls the thickness of the resulting coating. This type of die results in more intimate contact between the outer coating and the bare wire than the jacketing die.\nFiber drawing (polymers).\nFiber drawing is a hybrid process, in which gravity or another force is used to geometrically and mechanically alter the extruded fibers. This process not only reduces the cross section of the polymer fiber, but also increases the strength of the fibers by aligning the individual polymer molecules.\nBefore drawing, polymer melt is pushed through a die with a large number of small holes, known as a spinneret. Typically, the fibers are air cooled without any need for curing. If curing is needed, two methods are available: dry and wet spinning. In wet spinning, the polymer is dissolved and extruded through a spinneret into a chemical bath. In dry spinning, a solvent is allowed to evaporate as the fibers are cooled.\nTypically, fiber drawing occurs immediately after spinning. Application of an external force, either from gravity or take up rollers, causes the fibers to contract laterally and lengthen. This orients the individual polymer molecules along the length of the fiber, increasing strength. The radius of the fibers have been shown to decrease hyperbolically as they lengthen. Once the fibers solidify, they may begin to crystallize, with each grain initially randomly oriented. Further drawing will cause the crystal grains to elongate and reorient in the direction of the tensile axis, further strengthening the fibers.\nSpinning stability.\nIn practice, not all polymers are suitable for fiber spinning or drawing. This is particularly an issue in extensional-thinning polymers, where capillary failure or necking can cause separation of the melt before solidification.\nDraw resonance is the most common issue that can occur during drawing of the polymer melt, regardless of polymer suitability. Resonance occurs when the rate of mass flow is not constant between the spinneret and fiber take up roller, despite being constant at each of those individual components. When the mass flow rate is not constant, the diameter of the fiber will vary to accommodate the variation. Once started, this resonance may not correct itself, requiring a complete shutdown of the extrusion line.\nIt has been shown that draw resonance occurs once a critical drawdown ratio is exceeded; this ratio is dependent on the flow behavior (i.e. Newtonian, shear thinning) and viscoelastic behavior of the fluid. Draw resonance has not been found to be a function of the flow rate, however. A polymer melt approaching a Newtonian fluid such as PET can have a drawdown ratio of around 20, whereas highly shear thinning and viscoelastic polymer melts such as polyethylene, polystyrene, and polypropylene may have critical drawdown ratios as low as 3.\nTube forming.\nTube forming dies allow for continuous extrusion of thick walled (relative to blown film extrusion) tubes and pipes. The dies themselves are almost identical to those used in blown film extrusion; the only major difference is the gap between the inner mandrel and outer die wall. Once the polymer melt is extruded from the die, it is pulled away by take-up rollers. Cooling is accomplished through the use of water baths, or a large number of cooling fans. After cooling, the tube is either wound onto large spools (if flexible), or cut into pre-set lengths and stacked (if stiff). \nTubing with multiple lumens (holes) must be made for specialty applications. For these applications, the tooling is made by placing more than one mandrel in the center of the die, to produce the number of lumens necessary. In most cases, these mandrels are supplied with air pressure from different sources. In this way, the individual lumen sizes can be adjusted by adjusting the pressure to the individual mandrels.\nProfile extrusion.\nProfile extrusion, the extrusion of complex shapes such as rain gutters, structural supports, and other components, brings with it some of the most complex die designs of any extrusion process. This difficulty is due to two primary concerns: producing the initial, still molten profile, and then controlling for asymmetrical shrinkage and die swell due to varying wall thicknesses.\nUnlike in blown film, pipe, and sheet extrusion, the dies used in profile extrusion are rarely round or completely flat. Whereas a round (or flat) profile has uniform flow rates along all edges, this is not the case for more complex shapes. Take, for instance, the example of a simple, solid, square profile. The velocity of the melt is highest at the center of the die, and slowest at the edges and corners due to friction between the melt and die walls. When moving from the center of the die to the midpoint of one of the edges, the velocity gradient is high, especially near the outer die wall. However, when moving from the center to one of the corners, the velocity gradient is more gradual. As a result, the extruded square profile will experience more die swell at the edges than the corners, causing the once square profile to become more circular. This can be compensated for by bowing in the sides of the die so it approximates the shape of a four-pointed star; the sides of the polymer melt will now swell to the intended dimensions. \nAs the desired profile becomes more complex, the die in turn becomes more complex. Care must be taken to minimize weld lines, as well as ensuring complete filling of the die to prevent bubbles and other defects in the finished extruded profile. After the initial extrusion is complete, the molten polymer profile is cooled slightly before being run through a sizing die. This die ensures that the extruded profile meets specifications, and can correct the shape to fit those specifications. After sizing is complete, the profile is cooled before any further processing.\nCoextrusion.\nIn practice, many films, sheets, and other extruded parts are multilayered; this allows for optimization of a wide range of properties, such as oxygen permeability, strength, and stiffness. The primary difficulty of coextrusion is bridging the gap in properties between each layer. Adding a thin \"compatibility\" layer is a common solution to alleviating viscosity or stiffness incompatibilities.\nThere are two major die types for coextrusion: single manifold and multi manifold. Both types rely on a separate extruder for each polymer chemistry. In multi manifold dies, each layer is extruded separately and only combined just before the die lips. This die type is expensive due to the complex tooling required, but can alleviate vast differences in rheological behavior between the various layers. Single manifold dies form the multiple layers into a single layer, allowing contact between the polymer layers for a longer period of time. This ensures optimal bonding, but comes at the consequence of needing higher compatibility polymers.\nThere are two types of processing defects that can occur during coextrusion. The first defect is interface instability, causing unintended interface shapes. This can cause \"encapsulation\" of the higher viscosity melt by the lower viscosity melt, leading to poor final performance of the extruded part. The severity of this type of defect is proportional to the difference in viscosities between the two polymer melts. The other type of defect forms from oscillations in the melt flow, causing small wavelike patterns on the surface of the melt and reducing optical transparency.", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "2594462", "revid": "19502098", "url": "https://en.wikipedia.org/wiki?curid=2594462", "title": "Mitre box", "text": "A mitre box or miter box (American English) is a wood working appliance used to guide a hand saw for making precise cuts, usually 45° mitre cuts. Traditional mitre boxes are simple in construction and made of wood, while adjustable mitre boxes are made of metal and can be adjusted for cutting any angle from 45° to 90°. \nIn many workshops and jobsites mitre boxes have been superseded by the powered mitre saw, however advocates for mitre boxes argue that they are more accurate, safer, quieter, cheaper, and take up less space than a powered mitre saw. \nDescription.\nBasic mitre box.\nThe most common and simplest form of a mitre box is a U-shaped block made from wood, plastic or aluminium, which is open at the top and the ends. The box is made wide enough to accommodate the width of the workpieces to be cut. Slots are cut in the walls of the box at the precise angle at which the cut is to be made. These slots provide the guide for the saw to follow. Most commonly, the slots in the mitre box are cut at 45° and 90° angles.\nWhile wooden mitre boxes are mass produced, being simple in construction they are often made by woodworkers themselves from three pieces of wood screwed or glued together. The slots are then cut using the same saw that will be used with the box.\nWooden mitre boxes have a limited lifespan, as over time the saw wears away the sides and bottoms of the slots, reducing the accuracy of cuts. Some mitre boxes are fitted with guides across the top of the box to reduce wear on the slots and to provide rigidity to the box.\nMitre boxes can also be purpose-made by the woodworker for cutting angles other than 45° or for cutting compound (sloped) angles, or they can be designed for securing a particular size of workpiece.\nAdjustable mitre box.\nAn adjustable mitre box is designed for cutting any angle from 45° to 90° degrees. Made of metal, they consist of a base, a fence, and a mechanism for supporting a backsaw at the set angle. The workpiece is held against the fence while the saw is used. Historically a \"mitre saw\" is a type of backsaw with a wide blade designed for use with an adjustable mitre box, however the term is now more commonly used to refer to a powered mitre saw, which is a successor of the adjustable mitre box.\nUse.\nAs well as pieces of wood for use in joinery, the mitre box also sees common use in workshops and on jobsites for cutting various types of moulding. For precise work, a workpiece cut in a mitre box might then be further refined using a hand plane and shooting board.\nBasic mitre box.\nThe workpiece is placed in the box and the point at which the board is to be cut is lined up with the appropriate slot in the sides of the mitre box. The workpiece is then held or clamped in place. Backsaws are the most common hand saw used with mitre boxes, but other types of hand saw are also used. The saw is placed between the slots before sawing.\nAdjustable mitre box.\nThe workpiece is aligned with the saw and held or clamped against the fence. Depending on the mitre box design, the cut is then made with either a dedicated mitre saw, or another suitable saw that can fit between the guides.", "Engineering,_Manufacturing": 0.9997934699, "qwen": "Yes"}
{"id": "3468411", "revid": "8331790", "url": "https://en.wikipedia.org/wiki?curid=3468411", "title": "Cycloidal drive", "text": "A cycloidal drive or cycloidal speed reducer is a mechanism for reducing the speed of an input shaft by a certain ratio. Cycloidal speed reducers are capable of relatively high ratios in compact sizes with very low backlash.\nThe input shaft drives an eccentric bearing that in turn drives the cycloidal disc in an eccentric, cycloidal motion. The perimeter of this disc is geared to a stationary ring gear and has a series of output shaft pins or rollers placed through the face of the disc. These output shaft pins directly drive the output shaft as the cycloidal disc rotates. The radial motion of the disc is not translated to the output shaft.\nTheory of operation.\nThe input shaft is mounted eccentrically to a rolling-element bearing (typically a cylindrical roller bearing), causing the cycloidal disc to wobble in a circle. The cycloidal disc will independently rotate around the bearing as it is pushed against the ring gear. This is similar to planetary gearing. The direction of rotation of the disc and output is opposite to that of the input shaft.\nThe number of pins on the ring gear is larger than the number of pins on the cycloidal disc. This causes the cycloidal disc to rotate around the bearing faster than the input shaft is moving it around, giving an overall rotation in the direction opposing the rotation of the input shaft.\nThe cycloidal disc has holes that are larger (by an amount equal to the eccentricity of the input shaft) than the output roller pins that go inside them. The output pins will move around in the holes to achieve steady rotation of the output shaft from the wobbling movement of the cycloidal disc.\nThe reduction rate of the cycloidal drive is obtained from the following formula, where P means the number of the ring gear pins and L is the number of lobes on the cycloidal disc.\nSingle-stage efficiency approaches 93% and double-stage approaches 86%. Single stage reductions are available commercially up to 119:1 and double stage up to 7,569:1.\nThe cycloid disc is usually designed with a \"shortened cycloid\" in order to minimize the eccentricity of the disc and the associated unbalance forces at high speeds. For this reason, two cycloid discs are often mounted offset by 180°.\nMany modern precision drives provide the eccentric motion through multiple shafts that also transmit the output force, typically 2 to 5 shafts arranged in the same circular pattern as the output rollers of the most basic design. The shafts are driven through planetary-like gears by a central input shaft. Since these shafts are always aligned by the input gears this allows the output to be transmitted through roller bearings rather than intermittent surface contact. Due to the planetary input this is effectively a two-stage drive and may be designed to be directly driven by a high speed brushless motor. This type is often used in robot actuators.\nDisadvantages.\nDue to the eccentric nature of the drive, if the cycloidal disk is not balanced by a second disk or a counterweight, it will generate vibrations which propagate through the driven shafts and the body. This increases wear on the exterior teeth of the cycloidal disk and the component bearings. With two discs the static imbalance is corrected but a small dynamic imbalance remains. This is generally considered acceptable for most applications. To reduce vibration, high-speed drives use three or more discs to correct the imbalance; the outer discs move in unison, in opposition to the middle one, which is twice as massive.\nAdvantages.\nCycloidal drives can feature zero backlash and high torque capacity while being compact in size, unlike Involute gearboxes. They are useful in situations where low speed with high torque is required. Cycloidal drives may be designed with significantly higher contact areas for their size than any gear-based transmission such as epicyclic gearing. They apply force through many of the teeth at once, allowing very high torque output relative to size at the cost of requiring sliding contact.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "56065723", "revid": "20103693", "url": "https://en.wikipedia.org/wiki?curid=56065723", "title": "2018 Copa Sudamericana final stages", "text": "The 2018 Copa Sudamericana final stages were played from 21 August to 12 December 2018. A total of 16 teams competed in the final stages to decide the champions of the 2018 Copa Sudamericana.\nQualified teams.\nThe 16 winners of the second stage advanced to the round of 16.\nSeeding.\n\nStarting from the round of 16, the teams were seeded according to the second stage draw, with each team assigned a \"seed\" 1–16 corresponding to the tie they win (O1–O16) (Regulations Article 22.c).\nFormat.\n\nStarting from the round of 16, the teams played a single-elimination tournament with the following rules:\nBracket.\nThe bracket starting from the round of 16 was determined as follows:\n\nThe bracket was decided based on the second stage draw, which was held on 4 June 2018.\n\nRound of 16.\nThe first legs were played on 21–22 August, 18–20 and 26 September, and the second legs were played on 19, 25, 27 September, and 2–4 October 2018.\n\nMatch A.\n\"Tied 0–0 on aggregate, Santa Fe won on penalties and advanced to the quarterfinals (Match S1).\"\nMatch B.\n\"Tied 3–3 on aggregate, Bahia won on penalties and advanced to the quarterfinals (Match S2).\"\nMatch C.\n\"Tied 3–3 on aggregate, Nacional won on away goals and advanced to the quarterfinals (Match S3).\"\nMatch D.\n\"Junior won 2–1 on aggregate and advanced to the quarterfinals (Match S4).\"\nMatch E.\n\"Defensa y Justicia won 2–0 on aggregate and advanced to the quarterfinals (Match S4).\"\nMatch F.\n\"Fluminense won 4–0 on aggregate and advanced to the quarterfinals (Match S3).\"\nMatch G.\n\"Atlético Paranaense won 4–1 on aggregate and advanced to the quarterfinals (Match S2).\"\nMatch H.\n\"Tied 1–1 on aggregate, Deportivo Cali won on penalties and advanced to the quarterfinals (Match S1).\"\nQuarterfinals.\nThe first legs were played on 23–25 October, and the second legs were played on 30–31 October and 1 November 2018.\n\nMatch S1.\n\"Santa Fe won 3–2 on aggregate and advanced to the semifinals (Match F1).\"\nMatch S2.\n\"Tied 1–1 on aggregate, Atlético Paranaense won on penalties and advanced to the semifinals (Match F2).\"\nMatch S3.\n\"Fluminense won 2–1 on aggregate and advanced to the semifinals (Match F2).\"\nMatch S4.\n\"Tied 3–3 on aggregate, Junior won on away goals and advanced to the semifinals (Match F1).\"\nSemifinals.\nThe first legs were played on 7–8 November, and the second legs were played on 28–29 November 2018.\n\nMatch F1.\n\"Junior won 3–0 on aggregate and advanced to the finals.\"\nMatch F2.\n\"Atlético Paranaense won 4–0 on aggregate and advanced to the finals.\"\nFinals.\nIn the finals, if tied on aggregate, the away goals rule would not be used, and 30 minutes of extra time would be played. If still tied after extra time, the penalty shoot-out would be used to determine the winner (Regulations Article 28).\nThe first leg was played on 5 December, and the second leg was played on 12 December 2018.\n\n\"Tied 2–2 on aggregate, Atlético Paranaense won on penalties.\"", "Engineering,_Manufacturing": 0.9918608069, "qwen": "Yes"}
{"id": "365765", "revid": "46064651", "url": "https://en.wikipedia.org/wiki?curid=365765", "title": "Machining", "text": "Machining is a process in which a material (often metal) is cut to a desired final shape and size by a controlled material-removal process. The methods that have this common theme are collectively called subtractive manufacturing, which utilizes machine tools, in contrast to \"additive manufacturing\" (3D printing), which uses controlled addition of material.\nMachining is a part of the manufacture of many metal products, but it can also be used on other materials such as wood, plastic, ceramic, and composite material. A person who specializes in machining is called a machinist. A room, building, or company where machining is done is called a machine shop. Much of modern-day machining is carried out by computer numerical control (CNC), in which computers are used to control the movement and operation of mills, lathes, and other cutting machines. This increases efficiency, as the CNC machine runs unmanned, reducing labor costs for machine shops.\nHistory and terminology.\nThe precise meaning of the term \"machining\" has evolved over the past one and a half centuries as technology has advanced. In the 18th century, the word \"machinist\" meant a person who built or repaired machines. This person's work was primarily done by hand, using processes such as the carving of wood and the writing-forging and hand-filing of metal. At the time, millwrights and builders of new kinds of \"engines\" (meaning, more or less, machines of any kind), such as James Watt or John Wilkinson, would fit the definition. The noun \"machine tool\" and the verb \"to machine\" (\"machined, machining\") did not yet exist.\nAround the middle of the 20th century, the latter words were coined as the concepts they described evolved into widespread existence. Therefore, during the Machine Age, \"machining\" referred to (what we today might call) the \"traditional\" machining processes, such as turning, boring, drilling, milling, broaching, sawing, shaping, planing, abrasive cutting, reaming, and tapping. In these \"traditional\" or \"conventional\" machining processes, machine tools, such as lathes, milling machines, drill presses, or others, are used with a sharp cutting tool to remove material to achieve a desired geometry.\nSince the advent of new technologies in the post–World War II era, such as electrical discharge machining, electrochemical machining, electron beam machining, photochemical machining, and ultrasonic machining, the retronym \"conventional machining\" can be used to differentiate those classic technologies from the newer ones. Currently, \"machining\" without qualification usually implies the traditional machining processes.\nIn the decades of the 2000s and 2010s, as additive manufacturing (AM) evolved beyond its earlier laboratory and rapid prototyping contexts and began to become standard throughout all phases of manufacturing, the term \"subtractive manufacturing\" became common retronymously in logical contrast with AM, covering essentially any removal processes also previously covered by the term \"machining\". The two terms are effectively synonymous, although the long-established usage of the term \"machining\" continues. This is comparable to the idea that evolved because of the proliferation of ways to contact someone (telephone, email, IM, SMS, and so on) but did not entirely replace the earlier terms such as \"call\", \"talk to\", or \"write to\".\nMachining operations.\nThe three principal machining processes are classified as turning, drilling and milling. Other operations falling into miscellaneous categories include shaping, planing, boring, broaching, and sawing.\nAn unfinished workpiece requiring machining must have some material cut away to create a finished product. A finished product would be a workpiece that meets the specifications set out for that workpiece by engineering drawings or blueprints. For example, a workpiece may require a specific outside diameter. A lathe is a machine tool that can create that diameter by rotating a metal workpiece so that a cutting tool can cut metal away, creating a smooth, round surface matching the required diameter and surface finish. A drill can remove the metal in the shape of a cylindrical hole. Other tools that may be used for metal removal are milling machines, saws, and grinding machines. Many of these same techniques are used in woodworking.\nAs a commercial venture, machining is generally performed in a machine shop, which consists of one or more workrooms containing primary machine tools. Although a machine shop can be a stand-alone operation, many businesses maintain internal machine shops that support the business's specialized needs.\nMachining requires attention to many details for a workpiece to meet the specifications in the engineering drawings or blueprints. Besides the obvious problems related to correct dimensions, there is the problem of achieving the right finish or surface smoothness on the workpiece. The inferior finish found on the machined surface of a workpiece may be caused by incorrect clamping, a dull tool, or inappropriate presentation of a device. Frequently, this poor surface finish, known as chatter, is evident by an undulating or irregular finish and waves on the machined surfaces of the workpiece.\nOverview of machining technology.\nMachining is any process in which a cutting tool removes small chips of material from the workpiece (the workpiece is often called the \"work\"). Relative motion is required between the device and the work to perform the operation. This relative motion is achieved in most machining operations using a primary activity called \"cutting speed\" and a secondary movement called \"feed\". The shape of the tool and its penetration into the work surface, combined with these motions, produce the desired shape of the resulting work surface.\nMachining operations.\nThere are many kinds of machining operations, each of which is capable of generating a specific part geometry and surface texture.\nIn turning, a cutting tool with a single cutting edge removes material from a rotating workpiece to generate a cylindrical shape. The primary motion is provided by rotating the workpiece, and the feed motion is achieved by moving the cutting tool slowly in a direction parallel to the workpiece's rotation axis.\nDrilling is used to create a round hole. It is accomplished by a rotating tool that typically has two or four helical cutting edges. The device is fed in a direction parallel to its axis of rotation into the workpiece to form the round hole.\nIn boring, a tool with a single bent pointed tip is advanced into a roughly made hole in a spinning workpiece to enlarge the gap and improve its accuracy slightly. It is a fine-finishing operation used in the final stages of product manufacture.\nReaming is one of the sizing operations that removes a small amount of metal from a drilled hole.\nIn milling, a rotating tool with multiple cutting edges is moved slowly relative to the material to generate a plane or straight surface. The direction of the feed motion is perpendicular to the tool's axis of rotation. The rotating milling cutter provides speed motion. The two primary forms of milling are:\nOther conventional machining operations include shaping, planing, broaching, and sawing. Also, grinding and similar abrasive operations are often included within the category of machining.\nCutting tool.\nA cutting tool has one or more sharp cutting edges and is made of a harder material than the work material. The cutting edge serves to separate the chip from the parent work material. Connected to the cutting edge are the two surfaces of the tool:\nThe rake face, which directs the flow of the newly formed chip, is oriented at a certain angle and is called the rake angle \"α.\" It is measured relative to the plane perpendicular to the work surface. The rake angle can be positive or negative. The flank of the tool provides a clearance between the tool and the newly formed work surface, thus protecting the surface from abrasion, which would degrade the finish. This angle between the work and flank surfaces is called the relief angle. There are two basic types of cutting tools:\nA single-point tool has one cutting edge for turning, boring, and planning. During machining, the device's point penetrates below the work part's original work surface. The fact is sometimes rounded to a certain radius, called the nose radius.\nMultiple cutting-edge tools have more than one cutting edge and usually achieve their motion relative to the work part by rotating. Drilling and milling use turning multiple-cutting-edge tools. Although the shapes of these tools are different from a single-point device, many elements of tool geometry are similar.\nCutting conditions.\nRelative motion is required between the tool and work to perform a machining operation. The primary action is at a specific cutting speed. In addition, the device must be moved laterally across the work. This is a much slower motion called the feed. The remaining dimension of the cut is the penetration of the cutting tool below the original work surface, reaching the cut's depth. Speed, feed, and depth of cut are called the cutting conditions. They form the three dimensions of the machining process, and for certain operations, their product can be used to obtain the material removal rate for the process:\nwhere\nStages in metal cutting.\nMachining operations usually divide into two categories, distinguished by purpose and cutting conditions:\nRoughing cuts are used to remove a large amount of material from the starting work part as rapidly as possible, i.e., with a significant Material Removal Rate (MRR), to produce a shape close to the desired form but leaving some material on the piece for a subsequent finishing operation.\nFinishing cuts complete the part and achieve the final dimension, tolerances, and surface finish. In production machining jobs, one or more roughing cuts are usually performed on the work, followed by one or two finishing cuts. Roughing operations are done at high feeds and depths – feeds of 0.4–1.25  mm/rev (0.015–0.050 in/rev) and depths of 2.5–20 mm (0.100–0.750 in) are typical, but actual values depend on the workpiece materials. Finishing operations are carried out at low feeds and depths – dinners of 0.0125–0.04  mm/rev (0.0005–0.0015 in/rev) and depths of 0.75–2.0 mm (0.030–0.075 in) are typical. Cutting speeds are lower in roughing than in finishing.\nA cutting fluid is often applied to the machining operation to cool and lubricate the cutting tool. Determining whether a cutting fluid should be used and, if so, choosing the proper cutting fluid is usually included within the scope of the cutting condition.\nToday other forms of metal cutting are becoming increasingly popular. An example of this is water jet cutting. Water jet cutting involves pressurized water over 620 MPa (90 000 psi) and can cut metal and have a finished product. This process is called cold cutting, which eliminates the damage caused by a heat-affected zone, as opposed to laser and plasma cutting.\nRelationship of subtractive and additive techniques.\nWith the recent proliferation of additive manufacturing technologies, conventional machining has been retronymously classified, in thought and language, as a subtractive manufacturing method. In narrow contexts, additive and subtractive methods may compete with each other. In the broad context of entire industries, their Relationship is complementary. Each method has its advantages over the other. While additive manufacturing methods can produce very intricate prototype designs impossible to replicate by machining, strength and material selection may be limited.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "367107", "revid": "46293081", "url": "https://en.wikipedia.org/wiki?curid=367107", "title": "List of CAx companies", "text": "This is a list of computer-aided technologies (CAx) companies and their software products. Software using computer-aided technologies (CAx) has been produced since the 1970s for a variety of computer platforms. This software may include applications for computer-aided design (CAD), computer-aided engineering (CAE), computer-aided manufacturing (CAM) and product data management (PDM).\nThe list is far from complete or representative as the CAD business landscape is very dynamic: almost every month new companies appear, old companies go out of business, and companies split and merge. Sometimes some names disappear and reappear again.\nPast CAD Brands.\nAcquired, orphaned, failed or rebranded.\nIn-house CAD software.\nDeveloped by companies for their own use. Some are no longer used as the organizations are now using commercial systems.", "Engineering,_Manufacturing": 0.9999545813, "qwen": "Yes"}
{"id": "19883453", "revid": "6289403", "url": "https://en.wikipedia.org/wiki?curid=19883453", "title": "Spindle (tool)", "text": "In machine tools, a spindle is a rotating axis of the machine, which often has a shaft at its heart. The shaft itself is called a spindle, but also, in shop-floor practice, the word often is used metonymically to refer to the entire rotary unit, including not only the shaft itself, but its bearings and anything attached to it (chuck, etc.). Spindles are electrically or pneumatically powered and come in various sizes. They are versatile in terms of material it can work with. Materials that spindles work with include embroidery, foam, glass, wood, and etc.\nA machine tool may have several spindles, such as the headstock and tailstock spindles on a bench lathe. The main spindle is usually the biggest one. References to \"the spindle\" without further qualification imply the main spindle. Some machine tools that specialize in high-volume mass production have a group of 4, 6, or even more main spindles. These are called multispindle machines. For example, gang drills and many screw machines are multispindle machines. Although a bench lathe has more than one spindle (counting the tailstock), it is not called a multispindle machine; it has one main spindle.\nExamples of spindles include\nHigh speed spindle.\nHigh speed spindles are used strictly in machines, like CNC mills, designed for metal work. There are two types of high speed spindles, each with different designs:\nBelt-driven spindle.\nConsisting of spindle and bearing shafts held within the spindle housing, the belt-driven spindle is powered by an external motor connected via a belt-pulley system.\nIntegral motor spindle.\nA main component of this spindle is the motor, stored internally.\nBoth types, the belt-driven and the integral motor spindles, have advantages and disadvantages according to their design. Which one is more desirable depends on the purpose of the machine and product(s) being produced.\nCNC machines used with spindles.\nThe type of CNC machine being used with your spindle will vary. Common CNC machines used are:\nBeing that there are a variety of CNC machines available, it is important to choose the right one that fits your specifities.", "Engineering,_Manufacturing": 1.0000078678, "qwen": "Yes"}
{"id": "19888524", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=19888524", "title": "Microvia", "text": "Microvias are used as the interconnects between layers in high density interconnect (HDI) substrates and printed circuit boards (PCBs) to accommodate the high input/output (I/O) density of advanced packages. Driven by portability and wireless communications, the electronics industry strives to produce affordable, light, and reliable products with increased functionality. At the electronic component level, this translates to components with increased I/Os with smaller footprint areas (e.g. flip-chip packages, chip-scale packages, and direct chip attachments), and on the printed circuit board and package substrate level, to the use of high density interconnects (HDIs) (e.g. finer lines and spaces, and smaller vias).\nOverview.\nIPC standards revised the definition of a microvia in 2013 to a hole with depth to diameter aspect ratio of 1:1 or less, and the hole depth not to exceed 0.25mm. Previously, microvia was any hole less than or equal to 0.15 mm in diameter \nWith the advent of smartphones and hand-held electronic devices, microvias have evolved from single-level to stacked microvias that cross over multiple HDI layers. Sequential build-up (SBU) technology is used to fabricate HDI boards. The HDI layers are usually built up from a traditionally manufactured double-sided core board or multilayer PCB. The HDI layers are built on both sides of the traditional PCB one by one with microvias. The SBU process consists of several steps: layer lamination, via formation, via metallization, and via filling. There are multiple choices of materials and/or technologies for each step.\nMicrovias can be filled with different materials and processes: \nBuried microvias are required to be filled, while blind microvias on the external layers usually do not have any fill requirements. A stacked microvia is usually filled with electroplated copper to make electrical interconnections between multiple HDI layers and provide structural support for the outer level(s) of the microvia or for a component mounted on the outermost copper pad.\nMicrovia reliability.\nThe reliability of HDI structure is one of the major constraints for its successful widespread implementation in the PCB industry. Good thermo-mechanical reliability of microvias is an essential part of HDI reliability. Many researchers and professionals have studied the reliability of microvias in HDI PCBs. The reliability of microvias depends on many factors such as microvia geometry parameters, dielectric material properties, and processing parameters.\nMicrovia reliability research has focused on experimental assessment of the reliability of single-level unfilled microvias, as well as finite element analysis on stress/strain distributions in single-level microvias and microvia fatigue life estimation. Microvia failures identified from the research include interfacial separation (separation between the base of the microvia and the target pad), barrel cracks, corner/knee cracks, and target pad cracks (also referred to as microvia pull out). These failures result from the thermomechanical stresses caused by coefficient of thermal expansion (CTE) mismatch, in the PCB thickness direction, between the metallization in a microvia structure and the dielectric materials surrounding the metal. The following paragraph highlights some of the microvia reliability research.\nOgunjimi et al. looked at the effect of manufacturing and design process variables on the fatigue life of microvias, including trace (conductor) thickness, layer or layers of the dielectric around the trace and in the microvia, via geometry, via wall angle, ductility coefficient of the conductor material, and strain concentration factor. Finite element models were created with different geometries, and ANOVA method was used to determine the significance of the different process variables. The ANOVA results showed that the strain concentration factor was the most important variable, followed with the ductility factor, metallization thickness, and via wall angle. Prabhu et al. conducted a finite element analysis (FEA) on an HDI microvia structure to determine the effect of accelerated temperature cycling and thermal shock. Liu et al. and Ramakrishna et al. conducted liquid-to-liquid and air-to-air thermal shock testing, respectively, to studied the effect of dielectric material properties and microvia geometry parameters, such as microvia diameter, wall angle and plating thickness, on microvia reliability. Andrews et al. investigated single-level microvia reliability using IST (interconnect stress test), and considered the effect of reflow cycles of lead-free solder. Wang and Lai investigated the potential failure sites of microvias using finite element modeling. They found that filled microvias have a lower stress than unfilled microvias. Choi and Dasgupta introduced microvia non-destructive inspection method in their work.\nAlthough most microvia reliability research focuses on single-level microvias, Birch tested multiple-level stacked and staggered microvias using IST test. Weibull analysis on the test data showed that single- and 2-level stacked microvias last longer than 3- and 4-level microvias (e. g. 2-level stacked microvias experienced about 20 times more cycles to failure than 4-level stacked microvias).\nMicrovia voiding.\nOne challenge for high density interconnect board development, is to fabricate reliable microvias, especially for stacked microvias, without resulting in incomplete filling, dimples, or voids in the copper plating process. The authors of have been investigating the risk of microvias in terms of voids and other defects using both experimental testing and finite element analysis. They found that incomplete copper filling increases the stress levels in microvias and hence decreases microvia fatigue life.\nAs for voids, different voiding conditions, such as different void sizes, shapes, and locations result in different effects on microvia reliability. Small voids of a spherical shape lightly increase the microvia fatigue life, but extreme voiding conditions greatly reduce the duration of microvias.", "Engineering,_Manufacturing": 0.9999927282, "qwen": "Yes"}
{"id": "69508284", "revid": "1156829266", "url": "https://en.wikipedia.org/wiki?curid=69508284", "title": "Kearney and Trecker", "text": "Kearney and Trecker founded in 1898 by Edward J. Kearney and Theodore Trecker was a machine manufacturer based in West Allis, Wisconsin. It became one of the largest machine tool suppliers in the world.\nHistory.\nThe company was founded in 1898 and their first location was above a small shop. They soon became known for created milling machines and precision machine tools. By 1943 they were one of three largest milling machine manufacturers in the United States.\nIn 1965 the company was a leading automated tool maker, and had sales of more than 47 million dollars. They manufactured more than 100 different boring and milling machines. They merged with the Rockwell Standard corporation in 1965.\nBy 1955 the company had grown to become one of the largest machine tool suppliers in the world. The factories of Kearney & Trecker covered a 95-acre compound. In 1955 they had 2,250 employees.\nIn 1979 Kearney & Trecker merged with the Cross Company and became the Cross & Trecker, and just 12 years later, it was purchased by Giddings & Lewis, Inc.", "Engineering,_Manufacturing": 0.9998817444, "qwen": "Yes"}
{"id": "50048841", "revid": "7098284", "url": "https://en.wikipedia.org/wiki?curid=50048841", "title": "2016 Copa Libertadores final stages", "text": "The 2016 Copa Libertadores final stages were played from 26 April to 27 July 2016. A total of 16 teams competed in the final stages to decide the champions of the 2016 Copa Libertadores. Atlético Nacional won the title by defeating Independiente del Valle in the finals.\nQualified teams.\n\nThe winners and runners-up of each of the eight groups in the second stage qualified for the final stages.\n\nSeeding.\n\nThe qualified teams were seeded in the final stages according to their results in the second stage, with the group winners seeded 1–8, and the group runners-up seeded 9–16.\n\nFormat.\n\nIn the final stages, the 16 teams played a single-elimination tournament, with the following rules:\nBracket.\n\n\nRound of 16.\nThe first legs were played on 26–28 April, and the second legs were played on 3–5 May 2016.\n\nMatch A.\n\"Atlético Nacional won 4–2 on aggregate and advanced to the quarterfinals (Match S1).\"\nMatch B.\n\"UNAM won 2–1 on aggregate and advanced to the quarterfinals (Match S2).\"\nMatch C.\n\"Tied 2–2 on aggregate, Nacional won on away goals and advanced to the quarterfinals (Match S3).\"\nMatch D.\n\"Atlético Mineiro won 2–1 on aggregate and advanced to the quarterfinals (Match S4).\"\nMatch E.\n\"São Paulo won 5–3 on aggregate and advanced to the quarterfinals (Match S4).\"\nMatch F.\n\"Boca Juniors won 5–2 on aggregate and advanced to the quarterfinals (Match S3).\"\nMatch G.\n\"Independiente del Valle won 2–1 on aggregate and advanced to the quarterfinals (Match S2).\"\nMatch H.\n\"Rosario Central won 4–0 on aggregate and advanced to the quarterfinals (Match S1).\"\nQuarterfinals.\nThe first legs were played on 11–12 and 17 May, and the second legs were played on 18–19 and 24 May 2016.\n\nMatch S1.\n\"Atlético Nacional won 3–2 on aggregate and advanced to the semifinals (Match F1).\"\nMatch S2.\n\"Tied 3–3 on aggregate, Independiente del Valle won on penalties and advanced to the semifinals (Match F2).\"\nMatch S3.\n\"Tied 2–2 on aggregate, Boca Juniors won on penalties and advanced to the semifinals (Match F2).\"\nMatch S4.\n\"Tied 2–2 on aggregate, São Paulo won on away goals and advanced to the semifinals (Match F1).\"\nSemifinals.\nThe first legs were played on 6–7 July, and the second legs were played on 13–14 July 2016.\n\nMatch F1.\n\"Atlético Nacional won 4–1 on aggregate and advanced to the finals.\"\nMatch F2.\n\"Independiente del Valle won 5–3 on aggregate and advanced to the finals.\"\nFinals.\nThe first leg was played on 20 July, and the second leg was played on 27 July 2016.\n\n\"Atlético Nacional won 2–1 on aggregate.\"", "Engineering,_Manufacturing": 0.9227663279, "qwen": "Yes"}
{"id": "36555728", "revid": "1937176", "url": "https://en.wikipedia.org/wiki?curid=36555728", "title": "ION LMD", "text": "ION LMD system is one of the laser microdissection systems and a name of device that follows Gravity-Assisted Microdissection method, also known as GAM method. This non-contact laser microdissection system makes cell isolation for further genetic analysis possible. It is the first developed laser microdissection system in Asia.\nHistory.\nAt first, proto type of ION LMD system was developed in 2004.\nThe first generation of ION LMD was developed in 2005 and then the second generation(so-called G2) was developed in 2008. At last, the third generation(so-called ION LMD Pro) was developed in 2012.\nManufacturer.\nJungWoo F&B was founded in 1994, and offers various factory automation products for clients in semiconductor, consumer electronics, LCD, automotive manufacturing and ship-building industries. In 2003, the company entered the bio-mechanics business for the medical laboratory market and developed an ION LMD system which is utilized in cancer research.\nAwards.\nThis ION LMD system has got some reliable awards.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "65466271", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=65466271", "title": "Chris McMahon (academic)", "text": "Christopher Alan McMahon is a British mechanical engineer, academic and a researcher. He is a retired professor of engineering design and serves as senior research fellow and senior associate teacher at the University of Bristol.\nMcMahon has published two editions of a textbook on computer-aided design and manufacture, and authored a number of research papers focusing on engineering design and computer-aided design, especially concerning the application of computers to the management of information and uncertainty in design and design automation.\nEducation and early career.\nMcMahon graduated in mechanical engineering from the University of Bristol in 1978; prior to working in the railway and then automotive industries.\nAcademic career.\nMcMahon joined the University of Bristol as a lecturer in 1984, and worked there until 2002, when he joined the University of Bath. He was promoted to professor of engineering design in 2005, becoming director of Bath's Integrated Design and Manufacturing Research Centre. In 2012 he returned to the University of Bristol as professor of engineering design. In 2017 and 2018 he worked in the Department of Mechanical Engineering of the Technical University of Denmark.\nResearch.\nMcMahon's research interests include engineering design and computer-aided design, focusing on the application of computers to the management of information and uncertainty in design and design automation. He has carried out research in knowledge and information management for complex long-lived engineering products and systems, in information requirements of engineering designers and in systems to support their information organization and access. He has also researched in annotation in design, risk and uncertainty management in design, in component durability and reliability, and in eco-design and design for remanufacturing. The majority of his work has been carried out in conjunction with industry.\nHis research on computer aided design and manufacture (CADCAM) includes the introduction of a general purpose ontology-driven annotation approach for recording view-point dependent information in CAD, and work on the use of parametric and associative CAD systems to support the complex and lengthy design activities in the automotive industry.\nHe and his colleagues conducted in order to examine the barriers to improving information management in engineering companies, and to develop a set of core issues to inform their long term planning of information systems strategy. In a 2006 paper, hen proposed an information accessing framework using computational classification technologies. He also presented the use of multiple document structure views using decomposition schemes. His proposed framework combines automatic fragment extraction, markup technologies, document structure study and faceted classification for retrieving specific document fragment.\nMcMahon has made a number of observations on the diversity of design research, applying his experience in information management to the categorization of design research activities. He has also published influential review papers on knowledge management in engineering design, noting the broad division between personalisation and codification approaches, and on informatics in engineering design.\nProfessional activities.\nMcMahon is associated as an editorial board member with various journals including \"Research in Engineering Design\", \"Journal of Engineering Design\", \"Advanced Engineering Informatics\", \"International Journal of PLM\", \"AIEDAM\" and \"She Ji: Journal of Design\", \"Economics and Innovation\". In 2005, he joined the Board of Management of the Design Society and served as its president from 2011 to 2013. He is a Fellow of the Institution of Mechanical Engineers.\nTogether with Jimmie Browne of the National University of Ireland, Galway, in 1992 McMahon published a textbook on computer-aided design and manufacture \"CADCAM From Principles to Practice (\"second edition, 1998)\nIn 2020, McMahon published a translation of Philippe Bihouix's book, \"The Age of Low Tech: Towards a Technologically Sustainable Civilization\".", "Engineering,_Manufacturing": 0.9967535734, "qwen": "Yes"}
{"id": "36382558", "revid": "19921271", "url": "https://en.wikipedia.org/wiki?curid=36382558", "title": "Mitsubishi Logisnext", "text": "Mitsubishi Forklift Trucks is the brand name used for a range of materials handling products manufactured and distributed by Mitsubishi Heavy Industries (MHI) and several of its Mitsubishi Caterpillar Forklifts subsidiaries: MCFE Mitsubishi Caterpillar Forklift Europe, MCFA Mitsubishi Caterpillar Forklift America, MLAP Mitsubishi Logisnext Asia Pacific, and MCFC Mitsubishi Caterpillar Forklift (Shanghai).\nHistory.\nThe Mitsubishi Forklift Trucks brand was formed in 1992 when MHI entered a joint venture with Caterpillar Inc.\nIn February 2013, Mitsubishi Forklift Trucks has signed an agreement with the Japanese company Nichiyu to create Mitsubishi Nichiyu Forklift Co., Ltd.\nAs of 2018, Mitsubishi Forklift Trucks operates as a subsidiary of Mitsubishi Logisnext.\nProducts.\nMitsubishi Forklift Trucks products cover a range of counterbalance forklift trucks and warehouse equipment, including:\n• IC engine counterbalance trucks (diesel and LPG)\n• Electric counterbalance trucks\n• Powered pallet trucks\n• Stackers\n• Order pickers\n• Reach and multi-way trucks\nAlthough many of the designs and components are common to all regions, there are some differences in the product ranges across continents.\nProduction facilities.\nWorldwide headquarters:\nManufacturing centres:", "Engineering,_Manufacturing": 0.9998136163, "qwen": "Yes"}
{"id": "3523787", "revid": "13505698", "url": "https://en.wikipedia.org/wiki?curid=3523787", "title": "Piezoresistive effect", "text": "The piezoresistive effect is a change in the electrical resistivity of a semiconductor or metal when mechanical strain is applied. In contrast to the piezoelectric effect, the piezoresistive effect causes a change only in electrical resistance, not in electric potential.\nHistory.\nThe change of electrical resistance in metal devices due to an applied mechanical load was first discovered in 1856 by Lord Kelvin. With single crystal silicon becoming the material of choice for the design of analog and digital circuits, the large piezoresistive effect in silicon and germanium was first discovered in 1954 (Smith 1954).\nMechanism.\nIn conducting and semi-conducting materials, changes in inter-atomic spacing resulting from strain affect the bandgaps, making it easier (or harder depending on the material and strain) for electrons to be raised into the conduction band. This results in a change in resistivity of the material. Within a certain range of strain this relationship is linear, so that the piezoresistive coefficient\nwhere\nis constant.\nPiezoresistivity in metals.\nUsually the resistance change in metals is mostly due to the change of geometry resulting from applied mechanical stress. However, even though the piezoresistive effect is small in those cases it is often not negligible. In cases where it is, it can be calculated using the simple resistance equation derived from Ohm's law;\nwhere\nSome metals display piezoresistivity that is much larger than the resistance change due to geometry. In platinum alloys, for instance, piezoresistivity is more than a factor of two larger, combining with the geometry effects to give a strain gauge sensitivity of up to more than three times as large than due to geometry effects alone. Pure nickel's piezoresistivity is -13 times larger, completely dwarfing and even reversing the sign of the geometry-induced resistance change.\nPiezoresistive effect in bulk semiconductors.\nThe piezoresistive effect of semiconductor materials can be several orders of magnitudes larger than the geometrical effect and is present in materials like germanium, polycrystalline silicon, amorphous silicon, silicon carbide, and single crystal silicon. Hence, semiconductor strain gauges with a very high coefficient of sensitivity can be built. For precision measurements they are more difficult to handle than metal strain gauges, because semiconductor strain gauges are generally sensitive to environmental conditions (especially temperature).\nFor silicon, gauge factors can be two orders of magnitudes larger than those observed in most metals (Smith 1954). The resistance of n-conducting silicon mainly changes due to a shift of the three different conducting valley pairs. The shifting causes a redistribution of the carriers between valleys with different mobilities. This results in varying mobilities dependent on the direction of current flow. A minor effect is due to the effective mass change related to changing shapes of the valleys. In p-conducting silicon the phenomena are more complex and also result in mass changes and hole transfer.\nGiant piezoresistance in metal-silicon hybrid structures.\nA giant piezoresistive effect – where the piezoresistive coefficient exceeds the bulk value – was reported for a microfabricated silicon-aluminium hybrid structure. The effect has been applied to silicon-based sensor technologies.\nGiant piezoresistive effect in silicon nanostructures.\nThe longitudinal piezoresistive coefficient of top-down fabricated silicon nanowires was measured to be 60% larger than in bulk silicon.\nIn 2006, giant piezoresistance was reported in bottom-up fabricated silicon nanowires – a >30 increase in the longitudinal piezoresistive coefficient compared to bulk silicon was reported. The suggestion of a giant piezoresistance in nanostructures has since stimulated much effort into a physical understanding of the effect not only in silicon but also in other functional materials. \nPiezoresistive silicon devices.\nThe piezoresistive effect of semiconductors has been used for sensor devices employing all kinds of semiconductor materials such as germanium, polycrystalline silicon, amorphous silicon, and single crystal silicon. Since silicon is today the material of choice for integrated digital and analog circuits the use of piezoresistive silicon devices has been of great interest. It enables the easy integration of stress sensors with Bipolar and CMOS circuits.\nThis has enabled a wide range of products using the piezoresistive effect. Many commercial devices such as pressure sensors and acceleration sensors employ the piezoresistive effect in silicon. But due to its magnitude the piezoresistive effect in silicon has also attracted the attention of research and development for all other devices using single crystal silicon. Semiconductor Hall sensors, for example, were capable of achieving their current precision only after employing methods which eliminate signal contributions due to applied mechanical stress.\nPiezoresistors.\nPiezoresistors are resistors made from a piezoresistive material and are usually used for measurement of mechanical\nstress. They are the simplest form of piezoresistive devices.\nFabrication.\nPiezoresistors can be fabricated using wide variety of piezoresistive materials. The simplest form of piezoresistive silicon sensors are diffused resistors. Piezoresistors consist of a simple two contact diffused n- or p-wells within a p- or n-substrate. As the typical square resistances of these devices are in the range of several hundred ohms, additional p+ or n+ plus diffusions are a potential method to facilitate ohmic contacts to the device.\n\"Schematic cross-section of the basic elements of a silicon n-well piezoresistor.\"\nPhysics of operation.\nFor typical stress values in the MPa range the stress dependent voltage drop along the resistor Vr, can be considered to be linear. A piezoresistor aligned with the x-axis as shown in the figure may be described by\nwhere formula_5, \"I\", formula_6, formula_7, and formula_8 denote the stress free resistance, the applied current, the transverse and longitudinal piezoresistive coefficients, and the three tensile stress components, respectively. The piezoresistive coefficients vary significantly with the sensor orientation with respect to the crystallographic axes and with the doping profile. Despite the fairly large stress sensitivity of simple resistors, they are preferably used in more complex configurations eliminating certain cross sensitivities and drawbacks. Piezoresistors have the disadvantage of being highly sensitive to temperature changes while featuring comparatively small relative stress dependent signal amplitude changes.\nOther piezoresistive devices.\nIn silicon the piezoresistive effect is used in piezoresistors, transducers, piezo-FETS, solid state accelerometers and bipolar transistors.\nThe electrically-conductive packaging material Velostat is used by hobbyists to make pressure sensors due to is piezoresistive properties and low cost.", "Engineering,_Manufacturing": 0.9999330044, "qwen": "Yes"}
{"id": "3524912", "revid": "22045319", "url": "https://en.wikipedia.org/wiki?curid=3524912", "title": "English wheel", "text": "The English wheel, in Britain also known as a wheeling machine, is a metalworking tool that enables a craftsperson to form compound (double curvature) curves from flat sheets of metal such as aluminium or steel.\nDescription.\nThe process of using an English wheel is known as wheeling. Panels produced this way are expensive, due to the highly skilled and labour-intensive production method, but it has the key advantage that it can flexibly produce different panels using the same machine. It is a forming machine that works by surface stretching and is related in action to panel beating processes. It is used wherever low volumes of compound curved panels are required; typically in coachbuilding, car restoration, spaceframe chassis racing cars that meet regulations that require sheetmetal panels resembling mass production vehicles (NASCAR), car prototypes and aircraft skin components. English wheel production is at its highest in low-volume sports car production, particularly when more easily formed aluminium alloy is used. \nWhere high-volume production runs of panels are required, the wheel is replaced by a stamping press that has a much higher capital setup cost and longer development time than using an English wheel, but each panel in the production run can be produced in a matter of seconds. This cost is defrayed across a larger production run, but a stamping press is limited to only one model of panel per set of dies. The English wheel model shown is manually operated, but when used on thicker sheet metals such as for ship hulls the machine may be powered and much larger than the one shown here.\nConstruction.\nThe machine is shaped like a large, closed letter \"C\". At the ends of the C, there are two wheels. The wheel on the top is called the rolling wheel, while the wheel on the bottom is called the anvil wheel. (Some references refer to the wheels by their position: upper wheel and lower wheel.) The anvil wheel usually has a smaller radius than the rolling wheel. Although larger machines exist, the rolling wheel is usually wide or less, and usually in diameter, or less. \nThe rolling (top) wheel is flat in cross section, while the anvil (bottom) wheel is domed.\nThe depth of the C-shaped frame is called the throat. The largest machines have throat sizes of 120 cm (48 inches), while smaller machines have throat sizes of about 60 cm (24 inches). The C stands vertically and is supported by a frame. The throat size usually determines the largest size of metal sheet that the operator can place in the machine and work easily. On some machines, the operator can turn the top wheel and anvil 90 degrees to the frame to increase the maximum size of the work piece. Because the machine works by an amount of pressure between the wheels through the material, and because that pressure changes as the material becomes thinner, the lower jaw and cradle of the frame that holds the anvil roller is adjustable. It may move with a hydraulic jack on machines designed for steel plate, or a jackscrew on machines designed for sheet metals. As the material thins, the operator must adjust the pressure to compensate.\nFrame designs are the most significant element of this simple device. For the most part wheels have changed very little since the 19th century. The early English machines (as opposed to the American versions), such as Edwards, Kendrick, Brown, Boggs, and Ranalah, etc., had cast iron frames. These wheels, made during the 19th Century, had Babbitt metal plain bearings, making them difficult to push and pull the metal through when operated at high pressures. Later, when ball bearings came into use, the machines became more suitable for hard and thick material, such as 1/8” steel. Despite the advantages of cast iron, it has less than half the stiffness (Young's modulus) of steel and sometimes must be replaced by steel when a stiffer frame is needed. Steel frames made of solid flame-cut plate, or frames built-up of cut-and-welded plates, are common designs. Steel tubing, generally of square section, has been used for wheeling machine frames during the past 30 years, in the US particularly, where sheet metal shaping has become a hobby as well as a business. Tube-framed machines are reasonably priced and are available as kit-built machines or can be built easily from plans. The stiffest tubular frames have a fully triangulated external bracing truss. They are most effective on thinner or softer materials, such as 20 ga steel or .063\" aluminum. Cast frame machines, like the one pictured, are still available.\nA properly equipped machine has an assortment of anvil wheels. Anvil wheels, like dollies used with hammers in panel beating (which are also known as anvils) should be used to match the desired crown or curvature of the work piece.\nOperation.\nThe operator of the machine passes the sheet metal between the anvil wheel and the rolling wheel. This process stretches the material and causes it to become thinner. As the material stretches, it forms a convex surface over the anvil wheel. This surface is known as \"crown\". A high crown surface is very curved, a low crown surface is slightly curved. The rigidity and strength in the surface of a workpiece is provided by the high crown areas. The radius of the surface, after working, depends on the degree that the metal in the middle of the work piece stretches relative to the edge of the piece. If the middle stretches too much, the operator can recover the shape by wheeling the edge of the piece. Wheeling the edge has the same effect in correcting mis-shape due to over-stretching in the middle, as does shrinking directly on the overstretched area by the use of heat shrinking or Eckold-type shrinking. This is because the edge holds the shape in place. Shrinking the edge prior to wheeling aids the formation of shape during wheeling, and reduces the amount of stretching and thinning needed to reach the final shape. Shrinking processes reduce the surface area by thickening the sheet metal. Shrinking by hand is harder to do and slower than stretching using panel beating tools or wheeling, because of this it should only be used when absolutely necessary. Aluminium sheet should be annealed before wheeling because rolling at the mill during its production work hardens it. \nStrength and rigidity is also provided by the edge treatment such as flanging or wiring, after the fabrication of the correct surface contour has been achieved. The flange is so important to the shape of the finished surface that it is possible to fabricate some panels by shrinking and stretching of the flange alone, without the use of surface stretching.\nAdjustment.\nThe pressure of the contact area, which varies with the radius of the dome on the anvil wheel and the pressure of the adjusting screw, and the number of wheeling passes determines the degree to which the material stretches. Some operators prefer a foot adjuster so they can maintain constant pressure over varying sheet metal thickness for smoothing, with both hands free to manipulate the work piece. This style of adjuster is also helpful for blending the edge of high crown areas that are thinner, with low crown areas that are relatively unstretched. A drawback of the foot adjuster is that it can get in the way of very longitudinally curved panels, such as the cycle type mudguards (wings/fenders) used on motorcycles, pre-WW2 sports cars, and current open-wheeled cars like the Lotus / Caterham 7. \nTo address this problem, some wheeling machines have a hand adjuster close beneath the anvil yoke (also known a wheel holder) so such panels can curve underneath unobstructed. This type of machine typically has a diagonal lower 'C' shaped frame that curves lower to the floor, with a hand-operated adjuster close to the anvil wheel holder, instead of the horizontal and long vertical hand adjuster shown in the above picture. A third type of adjuster moves the top wheel up and down with the bottom anvil wheel left static.\nShaping.\nAt every fabrication stage, the operator must constantly reference the shape that they want to reproduce. This may involve the use of template paper, section templates (made using paper or thin sheet metal), station bucks, formers, profile gauges, profile templates and of course an original panel. Wheeling machines that feature a quick-release lever, which enables the operator to drop the anvil wheel away from the upper wheel so the work piece can be removed and inserted quickly without losing the pressure setting, are great time savers during this part of the process.\nThe operator must have painstaking patience to make many passes over an area on the sheet to form the area correctly. They may make additional passes with different wheels and in different directions (at 90 degrees for a simple double curvature shape, for example) to achieve the desired shape. Using the correct pressure and appropriate anvil wheel shape, and accurate close patterns of overlapping wheeling passes (or actually overlapping with low crown anvils) makes using the machine something of an art. Too much pressure produces a part that is undulating, marred, and stressed—while too little pressure makes the job take a long time. \nLocalised wheeling on one part of the panel is likely to cause mis-shaping in adjacent areas. Raising or stretching an area causes adjacent areas to sink, and correcting that may affect areas further away from the original panel working. This is because the tensions in the panel caused by stretching affect the panel shape further away than might be imagined. This means the operator must work over a large area of the panel, fixing these side effects while causing more side effects that must also be fixed. \nKey to producing the right shape is to have the right amount of stretched metal surface over this wider area. If this is achieved, it is possible to \"move\" the metal with minimal extra stretching, filling the low spots with metal from the high spots. This smoothing is almost like planishing using a moderate pressure setting, but is still heavier than that used for planishing. It is a time consuming and fiddly iterative process, that is one of the most difficult and skillful parts of wheeling. As the size of the panel/section increases, the work involved and the level of difficulty increases disproportionately. This is also a reason that very large panels can be very difficult to do and are made in sections. High crown panels/sections may need to be annealed due to work-hardening of the metal, which makes it brittle unworkable and liable to fracture. \nAfter achieving the correct basic shape with the correct amount of metal in the right places, the worker must blend the edges of high crown areas with low crown areas, so that the surface contour transitions from one to the other smoothly. After this, the final wheeling stage involves very light pressure wheeling to planish the surface to make it a smooth, cohesive shape. This stage does not stretch the metal but moves the already stretched metal around, so using the minimum anvil pressure and as wide an anvil as is possible with the panel shape, is essential.\nTypically, only small high crown panels, (such as repair sections) or large low crown panels (such as roofs), are made in one piece. Large low crown panels need two skilled craftsmen to support the weight of the panel.\nLimitations.\nFive key limitations of the machine are: \nThese limitations are the reasons why large high crown panels such as wings and fenders are often made in many pieces. The pieces are then welded together usually with one of two processes. TIG welding (Tungsten Inert Gas) produces less heat distortion, but produces a harder, more brittle weld that may cause problems when planishing/smoothing by hand, or in the wheeling machine. Oxy-acetylene welding joints don't have this drawback, provided they are allowed to cool to room temperature in air, but do produce more heat distortion. Panel joints may be achieved using autogenous welding – that is welding without filler rod (Oxy-acetylene or TIG processes), this is useful when finally smoothing the welding joints as it reduces the amount filing/grinding/linishing needed or almost eliminates it altogether. It also, more importantly, reduces heat distortion of the surface contour, which must be corrected on the wheel or with hammer and dolly.\nFinishing.\nThe final panel fabrication process, after achieving the correct surface contour, is some kind of edge treatment, such as flanging (sheet metal) or wire edging. This finishes and strengthens the edge. Typically, there is too much or too little metal in the flange, which pulls the panel out of shape after the flange is turned—so it must be stretched or shrunk to correct the surface shape. This is most easily done using Eckold shrinking and stretching, but can be done using heat shrinking or cold shrinking, by tucking and beating the tucked metal into itself, or by using a cold shrinking hammer and dolly. Stretching or shrinking the flange requires a correct profile hammer and dolly. The hammer and dolly must match the desired flange shape at the point of contact through the flange, (known as ringing the dolly) with the hammer. A lot of shrinking or stretching work hardens the flange and can cause cracks and tears. While these can be welded, it is much better to anneal the metal before this happens to restore its workability. \nAn English wheel is a better tool for a skilled craftsman for low-crown applications than manually hammering. Planishing manually using dollies and slapper files or planishing hammer, after hammer forming is very labour-intensive. Using a pear shaped mallet and sandbag to stretch the sheet metal (sinking), or by raising on a stake, speeds up the fabrication of higher crown sections. (A stake is a dolly, that can be much larger than hand held dollys, typically with a tapering square cross section casting underneath it. This is to mount it in a bench vice or a matching female hole in a beak anvil as used by blacksmiths and farriers.) A pneumatic hammer or power hammer is faster still. The English wheel is very effective when used for planishing, (for which it was originally patented in England), to a smooth final finish after these processes.", "Engineering,_Manufacturing": 0.9999746084, "qwen": "Yes"}
{"id": "4457298", "revid": "41893032", "url": "https://en.wikipedia.org/wiki?curid=4457298", "title": "Job production", "text": "Job production, sometimes called jobbing or one-off production, involves producing custom work, such as a one-off product for a specific customer or a small batch of work in quantities usually less than those of mass-market products. Job production consists of an operator or group of operators to work on a single job and complete it before proceeding to the next similar or different job. Together with batch production and mass production (flow production) it is one of the three main production methods.\nJob production can be classical craft production by small firms (making railings for a specific house, building/repairing a computer for a specific customer, making flower arrangements for a specific wedding etc.), but large firms use job production, too, and the products of job production are often interchangeable, such as machined parts made by a job shop. Examples include:\nFabrication shops and machine shops whose work is primarily of the job production type are often called job shops. The associated people or corporations are sometimes called jobbers.\nJob production is, in essence, manufacturing on a contract basis, and thus it forms a subset of the larger field of contract manufacturing. But the latter field also includes, in addition to jobbing, a higher level of outsourcing in which a product-line-owning company entrusts its entire production to a contractor, rather than just outsourcing parts of it.\nBenefits and disadvantages.\nKey benefits of job production include:\nDisadvantages include:\nEssential features.\nThere are a number of features that should be implemented in a job production environment, they include:", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "13256800", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=13256800", "title": "Motion system", "text": "Motion system in engineering and systems, is a component of a test and measurement system that provides motion to a load or loads in a one or many directions. Generally a motion system is made up of a set (or stack) of linear and rotational stages. A linear stage moves in a straight line, while a rotation stage moves in a partial or full circle. A stage can either be manually controlled with a knob control, or automated with a motion controller.\nA motion system generally is computer controlled and can perform fast, reliable, repeatable, and accurate positioning of loads. Most systems will support motion in X and Y directions, which is referred to as an XY stack. Often either a Z axis (up/down motion) or R axis (rotational motion) is placed on top of the XY stack.\nFor automated stages, a scale can be attached to the internals of the stage and an encoder used to measure the position on the scale and report this to the controller, thereby determining the precise position of the stage. This allows for a motion controller to reliably and repeatably move to set positions with the linear stage.\nExternal links.\nMotion Basics and Standards ", "Engineering,_Manufacturing": 0.9998349547, "qwen": "Yes"}
{"id": "1715922", "revid": "14013403", "url": "https://en.wikipedia.org/wiki?curid=1715922", "title": "Draw plate", "text": "A draw plate is type of die consisting of a hardened steel plate with one or more tapered holes through which wire is drawn to make it thinner. A typical plate will have twenty to thirty holes, so a wide range of diameters can be drawn.\nDrawing wire.\nBefore drawing, the draw plate is held securely in a vise or other fixture. The plate is oriented so that the wider end of a tapered opening can receive a metal wire which is to be pulled through it.\nAnnealed soft, ductile wire is filed at one end to give it an initial taper. The tapered end is inserted into a tapered hole with a final diameter just smaller than its current width. Special pliers, called draw tongs are used to hold the tip of the wire and pull it through, sometimes with the aid of grease or wax as a lubricant. Small-diameter wire may be drawn manually, while very thick wire may require a drawing bench with a crank to produce enough force.\nTypically, a wire can be drawn three times in sequence before it needs to be re-annealed. This must be done because drawing wire hardens it, which causes the wire to become brittle. Brittle wire that has not been annealed may snap during the drawing process (or develop microscopic or macroscopic cracks, which may weaken the piece or \"grow\" with further working).\nDraw plates reduce the thickness of wire by reshaping the metal; increasing its length while decreasing diameter. As such, a piece of wire will become considerably lengthened during the drawing process.\nWith a mandrel, a draw plate can be used to draw tubes of metal. Plates are available in many different sizes and shapes for drawing different shapes of wire, including round, square, oval, half-round, and hexagonal.", "Engineering,_Manufacturing": 1.0000014305, "qwen": "Yes"}
{"id": "58666552", "revid": "29669379", "url": "https://en.wikipedia.org/wiki?curid=58666552", "title": "Canon Tokki", "text": "Canon Tokki Corporation is a Japanese manufacturer of material deposition equipment for making OLED displays. It is a wholly owned subsidiary of Canon Inc. and has a near-monopoly in its main business field.\nHistory.\nThe company began producing Factory Automation systems, machine tools and production tools. In 1983 it began to produce vacuum thin film deposition equipment. In 1986, Tsugami Specialty Machine, Nagaoka Precision, Tsugami Robotics, and UPR Co., Ltd. merged to form Tokki Corporation Ltd. It began OLED material deposition equipment research in 1993, and in 1996, it started to sell its OLED material deposition equipment.\nIn 1999, Tokki developed the first OLED mass production system that processes both OLED and electrode material deposition as well as encapsulation by one system. The company also produces commercial encapsulation tools for laboratory and mass manufacturing. Canon Tokki and Sunic of Korea are the only two major manufacturers of production-scale OLED thin-film deposition equipment of G6 and above.\nIn 2001 it purchased the Niigata Factory from Niigata Keiso Co., Ltd., which became Tokki's main production base. In 2004, Tokki spun off its Factory Automation division forming the subsidiary Tokki Industries Co., Ltd. In 2009, Tokki moved its headquarters from Tokyo to its factory in Niigata. In 2010, Tokki sold Tokki Industries Co., Ltd to Marubeni Corporation. In 2010, Tokki was bought by Canon Inc., and in 2012 it changed its name to Canon Tokki.\nAn increase in orders enabled the company to double production capacity in 2016, but in 2018 the demand went down as a recovery in the equipment market had been lagged behind that of the display market.", "Engineering,_Manufacturing": 0.999607265, "qwen": "Yes"}
{"id": "58671006", "revid": "1147793441", "url": "https://en.wikipedia.org/wiki?curid=58671006", "title": "Medisize", "text": "Medisize AG Switzerland is a Swiss plastics processing company, owned by the Dutch Philips-Medisize Corporation. The Medisize Switzerland was original created as Createch AG.\nHistory.\nWerner Dubach founded the company Createch in Nürensdorf, which produced various bottles and closures for the medical, cosmetics and food sector in the injection blow, injection blow stretching molding and injection molding process. It was planned to build a building consisting of several parts, with office, production and storage space. On the one hand, granting problems, which led to massive changes in the construction project, led to financial problems. In addition, copyright complaints were filed for the production of food-grade food packaging for Danone yoghurts and quarks by the toy manufacturer Lego. This leads to the bankruptcy of the company Createch and the main building was not completely finished. A part is still in the shell and is used as a warehouse. The Createch was passed on by the Credit Suisse Bank until the Dutch Medisize Group took over the company. The Createch was then renamed to Medisize Switzerland AG.\nIn the meantime Werner Dubach had founded the company Terxo AG Switzerland in Wetzikon with some former Createch employees and the financial commitment of Markus Schellenberg. Werner Dubach had designed and patented a number of closures, some of which are still produced today by Medisize, Terxo and the German Terxo partner company Bericap. Werner Dubach retired some years ago.\nProducts.\nBranch of industry: Plastic industry and packaging industry, food and medical packaging\nMedisize Switzerland produces mainly closures for food packaging and cosmetics by means of injection molding machines and injection blowmachines, injection stretch blow molding machines as well as with assembly machines for further processing, but primarily packaging for medical products such as, for example, Eyedrops as well as bottles for drinks.\nThe Actifit bottles (polyethylene) for the milk processor Emmi, which produces medisize, have a great competitive pressure. This is because the company Terxo manufactures these bottles for Emmi too. In addition, the injection molding and injection blow molding machine manufacturer Ganahl, who has produced the corresponding tools for Terxo and Medisize, also manufactures such bottles by themselves. This means that there are three companies in the canton of Zurich, which all supply the same customer with the same product.\nEquipment.\nMedisize uses injection molding machines of Japanese and German origin. Three Italian machines are available for the injection blow-molding machines, but the majority of injection-molding machines are Jomar machines with vertical plasticizing cylinders, which come from the US. Medisize Switzerland is the first production company to use a fully electric injection blow molding machine. This was developed by a German toolmaking company.", "Engineering,_Manufacturing": 0.9996792078, "qwen": "Yes"}
{"id": "8373894", "revid": "3138265", "url": "https://en.wikipedia.org/wiki?curid=8373894", "title": "Automated truck loading systems", "text": "Automated Truck Loading Systems - ATLS has been commonly used in the material handling industry to refer to the automation of loading or unloading trucks and trailers with product either on or without pallets, slip sheets, racks, containers, using several different types of automated guided vehicle systems (AGV) or engineered conveyor belt systems that are integrated into vehicles, automating the shipping / receiving and logistics operations.\nThese conveyor systems are commonly referred to as\nSome of these systems are used to handle bulk products such as garbage, agriculture products, recycled tires, cotton, bark or sawdust. Manufacturing industries such as automotive, food & beverage, paper, consumer products, appliance manufacturers and uses ATLS systems for incoming materials and outgoing product to increase throughput and streamline production. The transportation industry relies heavily on ATLS material handling systems to rapidly move product via land, sea, and air.\nThe major advantages of ATLS are:\nATLS vehicle loading technologies significantly reduce the manpower required on the shipping and receiving docks, eliminate product damage, accidents, and ergonomic injuries related to lift-truck operation. Generally, products can be loaded quicker and product density is increased resulting in more payload per shipment which reduces shipping cost, using a loading automation system. Loading automation is often the key component to achieve complete plant automation.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "1898924", "revid": "21112944", "url": "https://en.wikipedia.org/wiki?curid=1898924", "title": "Compression molding", "text": "Compression molding is a method of molding in which the molding material, generally preheated, is first placed in an open, heated mold cavity. The mold is closed with a top force or plug member, pressure is applied to force the material into contact with all mold areas, while heat and pressure are maintained until the molding material has cured; this process is known as compression molding method and in case of rubber it is also known as 'Vulcanisation'. The process employs thermosetting resins in a partially cured stage, either in the form of granules, putty-like masses, or preforms. \nCompression molding is a high-volume, high-pressure method suitable for molding complex, high-strength fiberglass reinforcements. Advanced composite thermoplastics can also be compression molded with unidirectional tapes, woven fabrics, randomly oriented fiber mat or chopped strand. The advantage of compression molding is its ability to mold large, fairly intricate parts. Also, it is one of the lowest cost molding methods compared with other methods such as transfer molding and injection molding; moreover it wastes relatively little material, giving it an advantage when working with expensive compounds. \nHowever, compression molding often provides poor product consistency and difficulty in controlling flashing, and it is not suitable for some types of parts. Fewer knit lines are produced and a smaller amount of fiber-length degradation is noticeable when compared to injection molding. Compression-molding is also suitable for ultra-large basic shape production in sizes beyond the capacity of extrusion techniques. Materials that are typically manufactured through compression molding include: Polyester fiberglass resin systems (SMC/BMC), Torlon, Vespel, Poly(p-phenylene sulfide) (PPS), and many grades of PEEK. \nCompression molding is commonly utilized by product development engineers seeking cost effective rubber and silicone parts. Manufacturers of low volume compression molded components include PrintForm, 3D, STYS, and Aero MFG.\nCompression molding was first developed to manufacture composite parts for metal replacement applications, compression molding is typically used to make larger flat or moderately curved parts. This method of molding is greatly used in manufacturing automotive parts such as hoods, fenders, scoops, spoilers, as well as smaller more intricate parts. \nThe material to be molded is positioned in the mold cavity and the heated platens are closed by a hydraulic ram. Bulk molding compound (BMC) or sheet molding compound (SMC), are conformed to the mold form by the applied pressure and heated until the curing reaction occurs. SMC feed material usually is cut to conform to the surface area of the mold. The mold is then cooled and the part removed.\nMaterials may be loaded into the mold either in the form of pellets or sheet, or the mold may be loaded from a plasticating extruder. Materials are heated above their melting points, formed and cooled. The more evenly the feed material is distributed over the mold surface, the less flow orientation occurs during the compression stage.\nCompression molding is also widely used to produce sandwich structures that incorporate a core material such as a honeycomb or polymer foam.\nThermoplastic matrices are commonplace in mass production industries. One significant example are automotive applications where the leading technologies are long fibre reinforced thermoplastics (LFT) and glass fiber mat reinforced thermoplastics (GMT).\nIn compression molding there are six important considerations that an engineer should bear in mind:\nProcess definition.\nCompression molding is a forming process in which a plastic material is placed directly into a heated metal mold then is softened by the heat and therefore forced to conform to the shape of the mold, as the mold closes. Once molding is completed excess Flash may be removed. Typically, compression molding machines open along a vertical axis.\nProcess characteristics.\nThe use of thermoset plastic compounds characterizes this molding process from many of the other molding processes. These thermosets can be in either preform or granule shapes. Unlike some of the other processes we find that the materials are usually preheated and measured before molding. This helps to reduce excess flash. Inserts, usually metallic, can also be molded with the plastic. As a side note, remember not to allow any undercuts on the shape, it will make ejection especially difficult. Thermoplastic matrices with an inherent indefinite shelf-life and shorter cycle molding times are widely used and examples are shown in Ref 3.\nProcess schematic.\nCompression molding is one of the oldest manufacturing techniques for rubber molding. The process parameters include molding time, temperature, and pressure. Usually, a 300-400 ton clamp pressure is used. The typical mold is shaped like a clam shell with the bottom being the mold cavity. The molding press looked a lot like a ladle filled vertical press used for casting aluminum. Compression molding uses preforms made by an extruder and wink cutter (in which two blades meet at the center to cut the extrudate to length) or a roller die and die cutter.\nCompression molded water bottles are made from die-cut 3 inch by 6 inch sheets. One sheet is placed below a core and one sheet of equal size is placed above the core, and then the top of the mold is lowered by hand or by hoist to near shut. The mold is then pushed into the press, and the press is hydraulically closed to full pressure. The mold temperature is about 350 degrees. When the cycle ends (after about 3.5-4.0 minutes), the press opens and the mold is pulled out toward the operator. The operator opens the clam shell mold top and leans the top of the mold back against the press. Exposed is the bottle with the core still inside. While the bottle is still hot, the operator inserts prongs in between the bottle and the steel core and stretches the bottle at the neck to free it from the core.\nThe preforms for compression molded golf ball centers are extruded. The preform has a 1 inch by 1 inch round slug that stands up in the mold cavity. During the cycle, the operator loads the jig with slugs and places the jig over the mold. The preforms are released into the cavity of the mold when the slide tray is pulled. When the mold is opened, the lower platen lowers and the mold is hydraulically pushed out to the operator. The heat sheet (all molded parts from that cycle joined together by a parting line rind (flash)) is then placed in a transfer cart to be die cut.\nTypical tools and geometry produced.\nThree types of molds used are the flash plunger-type, straight plunger-type, and the \"landed\" plunger-type molds. The flash type mold must have an accurate charge of plastic and produces a horizontal flash (excess material protruding from the mold). The straight plunger-type mold allows for some inaccuracy in the charge of plastic and produces a vertical flash. The landed plunger type mold must have an accurate charge of plastic, and no flash is produced. Further details are explained in Ref 3.", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "13668392", "revid": "43205018", "url": "https://en.wikipedia.org/wiki?curid=13668392", "title": "Phantom inventory", "text": "Phantom inventory is a common expression for goods that an inventory accounting system considers to be on-hand at a storage location but are not available. This could be due to the items being moved without recording the change in the inventory accounting system, breakage, theft, data entry errors or deliberate fraud. The resulting discrepancy between the online inventory balance and physical availability can delay automated reordering and lead to out-of-stock incidents. \nIf not addressed, phantom inventory can result in:\nA number of techniques have been used to correct phantom inventory problems, including physical cycle counts, RFID tagging of items and statistical modelling of phantom inventory conditions.", "Engineering,_Manufacturing": 0.9968174696, "qwen": "Yes"}
{"id": "13675176", "revid": "43698778", "url": "https://en.wikipedia.org/wiki?curid=13675176", "title": "Industrial estates in Malta", "text": "Many factories in Malta are located in one of the several industrial estates throughout the archipelago. Malta Industrial Parks is a company which was created to manage industrial estates in Malta.\nMajor Industrial Areas.\nThe industrial estates include:\nBulebel Industrial Estate.\nBulebel Industrial Estate is one of the major industrial estates in Malta. Its namesake comes from milk production. Among the factories located here are:\nThe estate is found on the outskirts of Żejtun, near the localities of Tarxien and Fgura, and is not far from Malta International Airport.", "Engineering,_Manufacturing": 0.9999789, "qwen": "Yes"}
{"id": "26384121", "revid": "19502098", "url": "https://en.wikipedia.org/wiki?curid=26384121", "title": "Thermocompression bonding", "text": "Thermocompression bonding describes a wafer bonding technique and is also referred to as diffusion bonding, pressure joining, thermocompression welding or solid-state welding. Two metals, e.g. gold-gold (Au), are brought into atomic contact applying force and heat simultaneously. The diffusion requires atomic contact between the surfaces due to the atomic motion. The atoms migrate from one crystal lattice to the other one based on crystal lattice vibration. This atomic interaction sticks the interface together.\nThe diffusion process is described by the following three processes:\nThis method enables internal structure protecting device packages and direct electrical interconnect structures without additional steps beside the surface mounting process.\nOverview.\nThe most established materials for thermocompression bonding are copper (Cu), gold (Au) and aluminium (Al) because of their high diffusion rates. In addition, aluminium and copper are relatively soft metals with good ductility.\nBonding with Al or Cu requires temperatures ≥ 400 °C to ensure sufficient hermetical sealing. Furthermore, \"aluminium\" needs extensive deposition and requires a high applied force to penetrate the surface oxide, as it is not able to penetrate through the oxide.\nWhen using \"gold\" for diffusion, a temperature around 300 °C is needed to achieve a successful bond. Compared to Al or Cu, it does not form an oxide. This allows to skip a surface cleaning procedure before bonding.\n\"Copper\" has the disadvantage that the damascene process is very extensive. It also immediately forms a surface oxide which can, however, be removed by formic acid vapor cleaning. Oxide removal doubles as surface passivation.\nThe diffusion of these metals requires good knowledge of the CTE differences between the two wafers to prevent resulting stress. Therefore, the temperature of both heaters needs to be matched and center-to-edge uniform for synchronized wafer expansion.\nProcedural steps.\nPre-conditioning.\nOxidation and impurities in the metal films affect the diffusion reactions by reducing the diffusion rates. Therefore, clean deposition practices and bonding with oxide removal and re-oxidation prevention steps are applied. The oxide layer removal can be realized by various oxide etch chemistry methods. Dry etching processes, i.e. formic acid vapor cleaning, are preferred based on the minimization of the immersion in fluids and the resulting etching of the passivation or the adhesion layer. Using the CMP process, which is especially for Cu and Al required, creates a planarized surface with micro roughness around several nanometres and enables the achievement of void-free diffusion bonds. Further, a surface treatment for organic removal, e.g. UV-ozone exposure, is possible.\nMethods, i.e. plasma surface pretreatment, provide an accelerated diffusion rate based on an increased surface contact. Also the use of an ultra planarization step is considered to improve the bonding due to a reduction of material transport required for the diffusion. This improvement is based on a defined height Cu, Au and Sn.\nDeposition.\nThe metal films can be deposited by evaporation, sputtering or electroplating. Evaporation and sputtering, producing high quality films with limited impurities, are slow and hence used for micrometre and sub-micrometre layer thicknesses. The electroplating is commonly used for thicker films and needs careful monitoring and control of the film roughness and the layer purity.\nThe gold film can also be deposited on a diffusion barrier film, i.e. oxide or nitride. Also, an additional nano crystalline metal film, e.g. Ta, Cr, W, or Ti, can enhance the adhesion strength of the diffusion bond at decreased applied pressure and bonding temperature.\nBonding.\nThe factors of the chosen temperature and applied pressure depend on the diffusion rate. The diffusion occurs between the crystal lattices by lattice vibration. Atoms can not leap over free space, i.e. contamination or vacancies. Beside the most rapid diffusion process (surface diffusion), the grain boundary and the bulk diffusion exist.\n\"Surface diffusion\", also referred to as atomic diffusion, describes the process along the surface interface, when atoms move from surface to surface to free energy.\nThe \"grain boundary diffusion\" terms the free migration of atoms in free atomic lattice spaces. This is based on polycrystalline layers and its boundaries of incomplete matching of the atomic lattice and grains.\nThe \"diffusion through bulk crystal\" is the exchange of atoms or vacancies within the lattice that enables the mixing. The bulk diffusion starts at 30 to 50% of the materials melting point increasing exponentially with the temperature.\nTo enable the diffusion process, a high force is applied to plastically deform the surface asperities in the film, i.e. reducing bow and warp of the metal. Further, the applied force and its uniformity is important and depends on the wafer diameter and the metal density features. The high degree of force uniformity diminish the total force needed and alleviate the stress gradients and sensitivity to fragility. The bonding temperature can be lowered using a higher applied pressure and vice versa, considering that high pressure increases the chances of damage to the structural material or the films.\nThe bonding process itself takes place in a vacuum or forming gas environment, e.g. N2. The pressure atmosphere supports the heat conduction and prevents thermal gradients vertically across the wafer and re-oxidation. Based on the difficult control of thermal expansion differences between the two wafers, precision alignment and high quality fixtures are used.\nThe bonding settings for the most established metals are following (for 200 mm wafers):\nExamples.\n1. Thermocompression bonding is well established in the CMOS industry and realizes vertical integrated devices and production of wafer level packages with smaller form factors. This bonding procedure is used to produce pressure sensors, accelerometers, gyroscopes and RF MEMS.\n2. Typically, thermocompression bonds are made with delivering heat and pressure to the mating surface by a hard faced bonding tool. Compliant bonding is a unique method of forming this type of solid state bond between a gold lead and a gold surface since heat and pressure is transmitted through a compliant or deformable media. The use of the compliant medium ensures the physical integrity of the lead by controlling the extent of wire deformation. The process also allows one to bond a multiple number of gold wires of various dimensions simultaneously since the compliant media ensures contacting and deforming all the lead wires.", "Engineering,_Manufacturing": 0.999953866, "qwen": "Yes"}
{"id": "21731781", "revid": "16185737", "url": "https://en.wikipedia.org/wiki?curid=21731781", "title": "The International Journal of Advanced Manufacturing Technology", "text": "The International Journal of Advanced Manufacturing Technology is a peer-reviewed scientific journal published by Springer Science+Business Media in 18 issues per year. It covers all aspects of advanced manufacturing technology, such as robotics, artificial intelligence (including speech technology), vision and tactile sensing, grippers, programmable controllers, lasers and other advanced processes, programmable assembly, flexible manufacturing systems, computer integrated manufacturing, inspection, automatic test equipment, simulation, motors, controls and drives, local area networking, production planning and control, logistics and supply chain management, human factors, and economics. The editor-in-chief is A.Y.C. Nee (National University of Singapore).\nAbstracting and indexing.\nThe journal is abstracted and indexed in EBSCO databases, Science Citation Index Expanded, and Scopus. According to the \"Journal Citation Reports\", the journal has a 2017 impact factor of 2.601.", "Engineering,_Manufacturing": 0.9612669945, "qwen": "Yes"}
{"id": "21749554", "revid": "40834146", "url": "https://en.wikipedia.org/wiki?curid=21749554", "title": "Inventory theory", "text": "Material theory (or more formally the mathematical theory of inventory and production) is the sub-specialty within operations research and operations management that is concerned with the design of production/inventory systems to minimize costs: it studies the decisions faced by firms and the military in connection with manufacturing, warehousing, supply chains, spare part allocation and so on and provides the mathematical foundation for logistics. The inventory control problem is the problem faced by a firm that must decide how much to order in each time period to meet demand for its products. The problem can be modeled using mathematical techniques of optimal control, dynamic programming and network optimization. The study of such models is part of inventory theory.\nIssues.\nOne issue is infrequent large orders vs. frequent small orders. Large orders will increase the amount of inventory on hand, which is costly, but may benefit from volume discounts. Frequent orders are costly to process, and the resulting small inventory levels may increase the probability of stockouts, leading to loss of customers. In principle all these factors can be calculated mathematically and the optimum found.\nA second issue is related to changes in demand (predictable or random) for the product. For example, having the needed merchandise on hand in order to make sales during the appropriate buying season(s). A classic example is a toy store before Christmas: if the items are not on the shelves, they cannot be sold. And the wholesale market is not perfect; there can be considerable delays, particularly with the most popular toys. So, the entrepreneur or business manager will buy speculatively. Another example is a furniture store. If there is a six-week, or more, delay for customers to receive merchandise, some sales will be lost. A further example is a restaurant, where a considerable percentage of the sales are the value-added aspects of food preparation and presentation, and so it is rational to buy and store somewhat more to reduce the chances of running out of key ingredients. The situation often comes down to two key questions: confidence in the merchandise selling, and the benefits accruing if it does?\nA third issue comes from the view that inventory also serves the function of decoupling two separate operations. For example, work in process inventory often accumulates between two departments because the consuming and the producing department do not coordinate their work. With improved coordination this buffer inventory could be eliminated. This leads to the whole philosophy of Just In Time, which argues that the costs of carrying inventory have typically been underestimated, including both the direct, obvious costs of storage space and insurance, but also the harder-to-measure costs of increased variables and complexity, and thus decreased flexibility, for the business enterprise.\nInventory models.\nThe mathematical approach is typically formulated as follows:\na store has, at time formula_1, formula_2 items in stock. It then orders (and receives) formula_3 items, and sells formula_4 items, where formula_5 follows a given probability distribution. Thus:\nWhether formula_2 is allowed to go negative, corresponding to back-ordered items, will depend on the specific situation; if allowed there will usually be a penalty for back orders. The store has costs that are related to the number of items in store and the number of items ordered: \nThe store wants to select formula_3 in an optimal way, i.e. to minimize\nMany other features can be added to the model, including multiple products (denoted formula_13), upper bounds on inventory and so on. Inventory models can be based on different assumptions:\nClassic models.\nAlthough the number of models described in the literature is immense, the following is a list of classics:\nFurther reading.\nClassic books that established the field are:\nMany university courses in inventory theory use one or more of the following current textbooks:", "Engineering,_Manufacturing": 0.9986919761, "qwen": "Yes"}
{"id": "4815926", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=4815926", "title": "Ball screw", "text": "A ball screw (or ballscrew) is a mechanical linear actuator that translates rotational motion to linear motion with little friction. A threaded shaft provides a helical raceway for ball bearings which act as a precision screw. As well as being able to apply or withstand high thrust loads, they can do so with minimum internal friction. They are made to close tolerances and are therefore suitable for use in situations in which high precision is necessary. The ball assembly acts as the nut while the threaded shaft is the screw.\nIn contrast to conventional leadscrews, ball screws tend to be rather bulky, due to the need to have a mechanism to recirculate the balls.\nHistory.\nThe ball screw was invented independently by H.M. Stevenson and D. Glenn who were issued in 1898 patents 601,451 and 610,044 respectively.\nEarly precise screwshafts were produced by starting with a low-precision screwshaft, and then lapping the shaft with several spring-loaded nut laps. By rearranging and inverting the nut laps, the lengthwise errors of the nuts and shaft were averaged. Then, the very repeatable shaft's pitch is measured against a distance standard. A similar process is sometimes used today to produce reference standard screw shafts, or master manufacturing screw shafts.\nDesign.\nLow friction in ball screws yields high mechanical efficiency compared to alternatives. A typical ball screw may be 90 percent efficient, versus 20 to 25 percent efficiency of an Acme lead screw of equal size. Lack of sliding friction between the nut and screw lends itself to extended lifespan of the screw assembly (especially in no-backlash systems), reducing downtime for maintenance and parts replacement, while also decreasing demand for lubrication. This, combined with their overall performance benefits and reduced power requirements, may offset the initial costs of using ball screws.\nBall screws may also reduce or eliminate backlash common in lead screw and nut combinations. The balls may be preloaded so that there is no \"wiggle\" between the ball screw and ball nut. This is particularly desirable in applications where the load on the screw varies quickly, such as machine tools.\nBecause of their very high mechanical efficiency, especially compared to traditional lead screws, ball screws can potentially be back-driven (i.e., a linear force applied directly to the nut can induce a rotation of the shaft, an effect counterproductive to most uses). While this is usually of limited consequence to motorized applications, and potentially even provides a mild protective effect in some cases, it makes them generally unsuitable for application in manually actuated systems, such as hand-fed machine tools. The static torque and digital control of an appropriate servomotor can be made to resist and compensate, but hand cranked mechanisms would require additional mechanisms to prevent undesirable behaviors. Such undesirable behavior could range from simple loss of control of the machine, such as self-feeding (the tool of the machine causing motion of the axes without the control input of the operator), to potentially dangerous cases where unexpected force could be transmitted all the way to an operator's limbs and pose a risk of injury. Because an ordinary lead screw resists or even prohibits such reverse operation, they are inherently safer and more reliable for manual use. The magnitude of force needed to consequentially back-drive an Acme lead screw would usually be sufficient to destroy the mechanism, immobilizing the machine and absorbing any dangerous force before it could pose a risk to an operator.\nThe circulating balls travel inside the thread form of the screw and nut, and balls are recirculated through various types of return mechanisms. If the ball nut did not have a return mechanism the balls would fall out of the end of the ball nut when they reached the end of the nut. For this reason several different recirculation methods have been developed. An external ballnut employs a stamped tube which picks up balls from the raceway by use of a small pick-up finger. Balls travel inside the tube and are then replaced back into the thread raceway. An internal button ballnut employs a machined or cast button style return which allows balls to exit the raceway track and move one thread then reenter the raceway. An endcap return ball nut employs a cap on the end of the ball nut. The cap is machined to pick up balls coming out of the end of the nut and direct them down holes which are bored transversely down the ballnut. The complement cap on the other side of the nut directs balls back into the raceway. The returning balls are not under significant mechanical load and the return path may incorporate injection moulded low-friction plastic parts.\nA ball screw involves significantly more parts and surface interactions than many similar systems. While a basic lead screw is composed of only a solid shaft and a solid nut with simple mating geometries, a ball screw requires precisely formed curved contours and multi-part assemblies to facilitate the action of the bearing balls. This makes them more expensive to manufacture and sometimes to maintain, and provides more potential avenues for failure if the apparatus is not properly cared for.\nEquations.\nwith the rotary input driving in the conventional way, or\nif the linear force is backdriving the system\nWhere formula_3 is torque applied to screw or nut, formula_4 is linear force applied, formula_5 is ball screw lead, and formula_6 is ball screw efficiency. Selection of the standard to be used is an agreement between the supplier and the user and has some significance in the design of the screw. In the United States, ASME has developed the B5.48-1977 Standard entitled \"Ball Screws\".\nThe correct evaluation of the curvatures of ball screw grooves allows to accurately design the constructive parameters of this mechanism and to enhance its performance. The formulation commonly used in literature refers to the ball bearings geometry, ignoring the shape of the section’s profile and the helix angle. In particular, the first principal curvature is calculated asformula_7for the screw shaft groove, and asformula_8for the nut groove, where φ is the contact angle, formula_9 is the pitch circle radius and formula_10 is the ball radius.\nThe second principal curvature is simplyformula_11for the screw shaft groove and formula_12for the nut groove, in which formula_13 and formula_14 are, respectively, the conformity factors of the groove profiles of the screw shaft and nut.\nThese formulations do not take into account the shape of the groove profiles and the presence of the helix angle: more recent publications found the exact solution for the curvature of the grooves of screw shaft and nut. A new research proposes a new formulation which approximates the real curvature values with a maximum relative error of approximately 0.5%. Therefore, a much more precise formula for the first principal curvature of the screw shaft groove isformula_15andformula_16for the nut groove, where formula_17 is the helix angle.\nOperation.\nTo maintain their inherent accuracy and ensure long life, great care is needed to avoid contamination with dirt and abrasive particles. This may be achieved by using rubber or leather bellows to completely or partially enclose the working surfaces. Another solution is to use a positive pressure of filtered air when they are used in a semi-sealed or open enclosure.\nWhile reducing friction, ball screws can operate with some preload, effectively eliminating backlash (slop) between input (rotation) and output (linear motion). This feature is essential when they are used in computer-controlled motion-control systems, e.g., CNC machine tools and high precision motion applications (e.g., wire bonding).\nTo obtain proper rolling action of the balls, as in a standard ball bearing, it is necessary that, when loaded in one direction, the ball makes contact at one point with the nut, and one point with the screw. In practice, most ball screws are designed to be lightly preloaded, so that there is at least a slight load on the ball at four points, two in contact with the nut and two in contact with the screw. This is accomplished by using a thread profile that has a slightly larger radius than the ball, the difference in radii being kept small (e.g. a simple V thread with flat faces is unsuitable) so that elastic deformation around the point of contact allows a small, but non-zero contact area to be obtained, like any other rolling element bearing. To this end, the threads are usually machined as a \"gothic arch\" profile. If a simple semicircular thread profile were used, contact would only be at two points, on the outer and inner edges, which would not resist axial loading.\nTo remove backlash and obtain the optimum stiffness and wear characteristics for a given application, a controlled amount of preload is usually applied. This is accomplished in some cases by machining the components such that the balls are a \"tight\" fit when assembled, however this gives poor control of the preload, and cannot be adjusted to allow for wear. It is more common to design the ball nut as effectively two separate nuts which are tightly coupled mechanically, with adjustment by either rotating one nut with respect to the other, so creating a relative axial displacement, or by retaining both nuts tightly together axially and rotating one with respect to the other, so that its set of balls is displaced axially to create the preload.\nManufacture.\nBall screw shafts may be fabricated by rolling, yielding a less precise, but inexpensive and mechanically efficient product. Rolled ball screws have a positional precision of several thousandths of an inch per foot.\nBall screw are classified using \"accuracy grades\" from C0 (most precise) to C10. High-precision screw shafts are typically precise to one thousandth of an inch per foot (830 nanometers per centimeter) or better. They have historically been machined to gross shape, case-hardened, and then ground. The three step process is needed because high temperature machining distorts the work-piece. Hard whirling is a recent (2008) precision machining technique that minimizes heating of the work, and can produce precision screws from case-hardened bar stock. Instrument quality screw shafts are typically precise to 250 nanometers per centimeter. They are produced on precision milling machines with optical distance measuring equipment and special tooling. Similar machines are used to produce optical lenses and mirrors. Instrument screw shafts are generally made of Invar, to prevent temperature from changing tolerances too much.\nApplications.\nBall screws are used in aircraft and missiles to move control surfaces, especially for electric fly by wire, and in automobile power steering to translate rotary motion from an electric motor to axial motion of the steering rack. They are also used in machine tools, robots, and precision assembly equipment. High precision ball screws are used in steppers for semiconductor manufacturing.\nA ball screw is used to expand the Deployable Tower Assembly (DTA) structure on the James Webb Space Telescope.\nSimilar systems.\nAnother form of linear actuator based on a rotating rod is the threadless ballscrew, a.k.a. \"rolling ring drive\". In this design, three (or more) rolling-ring bearings are arranged symmetrically in a housing surrounding a smooth (threadless) actuator rod or shaft. The bearings are set at an angle to the rod, and this angle determines the direction and rate of linear motion per revolution of the rod. An advantage of this design over the conventional ballscrew or leadscrew is the practical elimination of backlash and loading caused by preload nuts.", "Engineering,_Manufacturing": 0.9999997616, "qwen": "Yes"}
{"id": "4821932", "revid": "42941688", "url": "https://en.wikipedia.org/wiki?curid=4821932", "title": "Product structure modeling", "text": "Product structure is a hierarchical decomposition of a product, typically known as the bill of materials (BOM).\nAs business becomes more responsive to unique consumer tastes and derivative products grow to meet the unique configurations, BOM management can become unmanageable. For manufacturers, a bill of materials (BOM) is a critical product information record that lists the raw materials, assemblies, components, parts and the quantities of each needed to manufacture a product.\nAdvanced modeling techniques are necessary to cope with configurable products where changing a small part of a product can have multiple impacts on other product structure models. Concepts within this entry are in capital letters in order to indicate these concepts.\nSeveral concepts are related to the subject of product structure modeling. All these concepts are discussed in this section. These concepts are divided into two main aspects. First the product breakdown is discussed which involves all the physical aspects of a product. Second, different views at the product structure are indicated.\nProduct breakdown.\nFigure 1 illustrates the concepts that are important to the structure of a product. This is a meta-data model, which can be used for modeling the instances in a specific case of product structuring.\nThe core of the product structure is illustrated by the product components (\"items\") and their \"relationships\". Thus, this involves the linking between items related to the product.\nThe \"assembly\" can consist of \"subassemblies and \"parts\", whereas \"subassemblies\" can also consist of other subassemblies or part. Thus, this is typically hierarchically ordered. These concepts are generalized into the concept of item. This classification is overlapping, because a subassembly could be a part in another assembly configuration.\nDue to differentiation and variation of items several concepts must be indicated into the product breakdown structure. Three concepts are involved in this differentiation, namely \"alternatives\", variants and \"revisions\". An alternative of an item is considered as a substitute for that particular item, whereas a variant is another option of an item which the consumer can choose. When an error occurs at a part or subassembly, it needs to be revised. This revision indicates the change history of the item.\nProduct structure views.\nProduct structure views are made upon several activity domains within the company. Due to the fact not everyone in the company has to have a detailed overview of the product several components with their attributes can be extracted.\nWhen the \"Master Structure\" is made out of the several items of the product assembly, multiple views can be made upon this \"Master Structure\". Thus this \"Master Structure\" contains every item in detail, which is important to the \"Assembly\" of the product.\nThe modeling process.\nThe process of constructing the product model consists of six main activities, which can be decomposed in several sub-activities. The next table describes these activities and the sub-activities within them provided with a description about this activity.\nProcess-data model.\nWhen combining the activities with the concepts of the product structure model it will result in a process-data diagram. This diagram displays the steps which need to be taken within the process of product structure modeling together with the deliverables, at the right side, which are outcomes of these activities.\nExample.\nThis example discusses the product structure modeling within car manufacturing. This will be discussed through the main activities which are identified within the process of product structure modeling.\nDefine product components.\nFirst, all components are identified and indicated. In the area of car manufacturing, the product components are as follows. A car (ASSEMBLY) consists of several SUBASSEMBLIES such as the body and the engine of the car. The engine for example is assembled in several parts such as screws and small pipes.\nDefine product assortment.\nIn case of car manufacturing instances of these concepts can be made. For example an engine has several alternatives. For example a car manufacturer can choose between an engine made in America or Japan.\nWithin these different engines, variants exist. Initially an engine can be made as a 1.6 engine, but a variant, such as a 1.8 engine, can be made of this engine. Thus the 1.6 engine is used as base concept for the new 1.8 engine.\nProduct structuring.\nAn example of a correlation between items within car manufacturing can be indicated as follows. The engine is connected to the body with several screws. Thus, these two items must be linked by the concept of a relationship.\nCreate master structure.\nAfter structuring the product with all the listed items and relationship between them this must be combined into one MASTER STRUCTURE which contains all of the details of the product. In case of the car, all items from engine to screw must be documented in one MASTER STRUCTURE.\nDocumenting.\nWhen the MASTER STRUCTURE of the car is created one must link this structure with documents which contains the product definition of this specific car. Primarily, this consists of an extensive description of the car which is linked to the MASTER STRUCTURE of this product.\nDefine product structure views.\nIn case of the car manufacturer multiple views can be derived from the car assembly. For example a structure from a sales point of view will need more detail about the functions and characteristics of the car rather than detailed information about the body. Thus a sales manager needs information about the color of the car or the type of gear (automatic of manual).\nFrom a purchasing view more information is needed about the mixing of the paint instead of the general color, which is only needed for the customer. Purchasing department also needs more information about the suppliers of the used components within the manufacturing of the car, so they can easily overview where which component is used and which supplier it comes from.", "Engineering,_Manufacturing": 0.9985228181, "qwen": "Yes"}
{"id": "11999012", "revid": "20981929", "url": "https://en.wikipedia.org/wiki?curid=11999012", "title": "Scribing (cartography)", "text": "Scribing was used to produce lines for cartographic map compilations before the use of computer-based geographic information systems. Lines produced by manual scribing are sharp, clear and even. \nAn impression of the corrected compilation sheet is photographed onto scribe sheet material or drawn using pencil. While working over a light table, lines on the scribe sheet are traced with a metal or sapphire-tipped scribe tool to remove thin lines of translucent coating to produce a handmade negative image. This compares with drafting, where an ink image is made on tracing paper by depositing ink using a pen to produce a positive image. Scribing produces a result superior to drafting, but is more time-consuming. A separate stylus is required for each thickness of line required. For example, a contour line might require a 0.15mm stylus whereas a major road might require a 0.5mm stylus.\nThe scribe sheet is made of a stable plastic base material and coated with a material which is designed for easy removal using a scribing tool to produce a cleanly cut line. Various colours are used, and orange is said to produce the least eye-strain for the cartographer.\nOne scribe sheet is produced for each map colour. Corrections can be made by \"duffing\" (re-coating) the scribe sheet with special duffing liquid. The detail can then be re-scribed. Printing plates are produced from the finished scribe sheets, one for each colour of the map. \nScribe tools.\nA tripod or trolley arrangement is used to hold the scribe stylus. A stylus of required thickness is set in the trolley and the surface material is removed by applying light pressure as the trolley is moved over the image. Care must be taken to ensure the base material is not gouged or distorted.\nEither a round point or chisel point stylus may be used. Chisel points must be set at right angles to the direction of movement. As well as single line gravers, double and triple lines can be produced with double and triple graver stylus. Small circles can be produced using motorised versions of scribing tools, and symbols, figures etc., can be produced using plastic or metal templates.\nArea symbols.\n‘Peelcoat’ is used to produce a negative of an area of detail such as a lake or forest. The border of the area is cut or scribed on the peelcoat and the coat of the sheet within the area is peeled off to produce a negative image.\nA stipple pattern can be used to produce an area symbol over the peeled surface. A stipple sheet with a simple repeating symbol (such as that for swamp or sand) is combined with the area by photographing the stipple onto the peelcoat.", "Engineering,_Manufacturing": 0.9970931411, "qwen": "Yes"}
{"id": "38391021", "revid": "925940984", "url": "https://en.wikipedia.org/wiki?curid=38391021", "title": "Almen round", "text": "An Almen round is a thin round disk used to quantify the intensity of a shot peening process. Developed in 1994 by Rudolf Bosshard in Switzerland, it is a modification of the Almen strip method, which is used worldwide as a surface treatment testing method in the field of shot peening. The basic principle is the same, but due to the simple shape and minimized size, the Almen round is more suitable for automated processing and installation on dummy rigs. Also instead of the Almen block according SAE J442, here a matching device is used and if connected to electronic processing unit, the Almen value according AMS-S-13165 (predecessor MIL-S-13165 Rev.C) can be evaluated in one run.\nTest specimen.\nThe Almen round is a circular cutting from an original Almen strip normally in material SAE 1070. It can be either of a \"A\", \"C\" or \"N\" type offered in various quality grades. The standard strip allows the splitting into four pieces rounds, which have a diameter of 18.7 mm, by either waterjet or laser technique. Therefore, the spaces are maintained in respect of material and thickness. The flatness test to follow is simple and imprecise pieces can be eliminated.\nSpecimen holder.\nIn the endeavor to standardize the parameters, the clamping down of the Almen rounds follows a strict geometry. The clamping head fixes the Almen round in correct manner, thus important for all related procedure. When working with the monitoring sensor, the specimen is preloaded to increase overall accuracy.\nMeasuring technique.\nOther than the Almen strip method with the two steps: 1. Processing with holder and 2. Measuring with gage, the Almen round technique combines those activities. The specimen holder is complemented with a measuring system, e.g. a distance sensor system of various kinds to complete the monitoring sensor. While bombarded by shot, the captured Almen round gets bent towards the direction of the attack. The linear transformation gets converted into an electric signal sent to a processing unit. With calibration discs, errors will be minimalized. For the offline measuring of an individual round, the online monitoring sensor or an appropriate device will also be used.\nSignal processing.\nThus the equipment is designed for direct exposure to the shot stream, the deformation of the round can be monitored online and directly converted into the Almen standard arc high definition (SAE J443) either in mm or inches. Such a process time will be in the range of less than 5 to 40 seconds. If on screen, the graph shows the basis for the calculation algorithm, also the essential point in mm or inches that is the output information equivalent to the original Almen round definition.\nAdvanced application.\nMany so called \"critical parts\" require a test run with dummy parts. Therefore the Almen round is captured in a special mount that can be screwed or glued onto the dummy or even on a real part. In such a case an online monitoring is not possible, the specimens must get removed and then measured separately with the monitoring sensor. In this case, only the arc height can be traced. So this application should be in combination with a parallel running online process.\nField of application.\nThe Almen round can be utilized in aircraft and automotive industry, research and subcontracting peening enterprises.\nApplication restriction.\nAs the Almen strip principle has been established in 1942 and international standardization has reached a top-level. The strip work routine is a fixed procedure in practical peening technology. The Almen round principle is more accurate and offers a considerable working time reduction. But as there is no international approved standardization, this technique will be used for special applications only.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "38399847", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=38399847", "title": "Terex THS15 Motorscraper", "text": "The Terex THS15 Motorscraper was a concept machine scraper displayed for the first time at Minexpo 2000. This machine features some unusual design concepts, including an adjustable cutting edge on the bowl to reduce friction when loading. Other notable features were the rear-mounted drivetrain (there was no engine on the front module) and a hydrostatic transmission, which featured hydraulic wheel motors. At least two prototypes were made, and these featured noticeable differences in front end styling. A digital copy of the brochure for this machine is available through ozebooks. Both the THS15 scrapers were spotted for sale in used machinery dealers by 2011 and their fate is unknown. Terex never went ahead with production and subsequently abandoned motor scraper manufacture altogether.\nTransmission.\nHydrostatic transmissions have many benefits; however, they are not usually suited to machines that travel at higher speeds over longer distances. The hydrostatic drive may have been a contributing factor in abandoning the project. Changes in the way earthmoving is done, including the use of excavators and dumptrucks, has also eroded the market for scrapers. Therefore, this machine exhibited many revolutionary design concepts but was probably too costly to put into production in a declining market sector.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "20182719", "revid": "35246606", "url": "https://en.wikipedia.org/wiki?curid=20182719", "title": "Cartoning machine", "text": "A cartoning machine or cartoner, is a packaging machine that forms cartons: erect, close, folded, side seamed and sealed cartons.\nPackaging machines which form a carton board blank into a carton filled with a product or bag of products or number of products say into single carton, after the filling, the machine engages its tabs / slots to apply adhesive and close both the ends of carton completely sealing the carton.\nCartoning machines can be divided into two types:\nA cartoning machine which picks a single piece from stack of folded carton and erects it, fills with a product or bag of products or number of products horizontally through an open end and closes by tucking the end flaps of the carton or applying glue or adhesive. The product might be pushed in the carton either through the mechanical sleeve or by pressurized air. For many applications however, the products are inserted into the carton manually. This type of Cartoning machine is widely used for packaging foodstuffs, confectionery, medicine, cosmetics, sundry goods, etc.\nA cartoning machine which erects a folded carton, fills with a product or number of products vertically through an open end and closes by either tucking the end flaps of the carton or applying glue or adhesive, is called an end load cartoning machine. Cartoning machines are widely used for packaging bottled foodstuffs, confectionery, medicine, cosmetics, etc., and can vary based on the scale of business.", "Engineering,_Manufacturing": 1.0000038147, "qwen": "Yes"}
{"id": "3294328", "revid": "32990417", "url": "https://en.wikipedia.org/wiki?curid=3294328", "title": "Demand chain", "text": "The term demand chain has been used in a business and management context as contrasting terminology alongside, or in place of, \"supply chain\". Madhani suggests that the demand chain \"comprises all the demand processes necessary to understand, create, and stimulate customer demand\". Cranfield School of Management academic Martin Christopher has suggested that \"ideally the supply chain should become a demand chain\", explaining that ideally all product logistics and processing should occur \"in response to a known customer requirement\".\nConcept.\nAnalysing the firm's activities as a linked chain is a tried and tested way of revealing value creation opportunities. The business economist Michael Porter of Harvard Business School pioneered a value chain approach: \"the value chain disaggregates the firm into its strategically relevant activities in order to understand the costs and existing potential sources of differentiation\". It is the micro mechanism at the level of the firm that equalizes supply and demand at the macro market level.\nEarly applications in distribution, manufacturing and purchasing collectively gave rise to a subject known as supply chain management. Old supply chains have been transformed into faster, cheaper and more reliable modern supply chains as a result of investment in information technology, cost-analysis and process-analysis.\nMarketing, sales and service are the other half of the value-chain, which collectively drive and sustain demand, and are known as the Demand Chain. Progress in transforming the demand side of business is behind the supply side, but there is growing interest today in transforming demand chains.\nWithout marketing / supply chain management (SCM) cross-functional collaboration, firms cannot be expected to respond optimally and promptly to customers' requirements.\nChallenges.\nAt present, there appear to be four main challenges to progress in transforming demand chains and making them faster, leaner and better:\nLinking supply chains to demand – \"demand driven\" v \"forecast push\".\nThe challenge of improving the link between demand and supply has occupied many supply chain specialists in recent years; and concepts such as \"demand-driven supply chains\" (Demand Driven MRP), and customer-driven supply chains have attracted attention and have become the subject of conferences and seminars.\nThe fundamental attribute of a \"demand driven\" supply chain is that material movements (or replenishment execution) are directly triggered by demand itself. Those parts of a supply chain that directly respond to orders, such as \"make to order\" or \"assemble to order\" are, therefore, \"demand driven\".\n\"Make to stock\" supply chains can also be \"demand driven\" if individual echelon replenishment quantities are determined by the need to simply replace stock that has been consumed by the immediate downstream activity (i.e.. sold to a customer, used by a manufacturing process or moved to another distribution location). This is in contrast to \"forecast push\" supply chains in which the customer facing echelon replenishment quantity is calculated using a forecast of future requirements and a minimum stock balance (i.e. safety stock) while all upstream activities are coupled directly to the forecast using MRP calculations.\nDue to inevitable forecast inaccuracy, \"forecast push\" supply chains suffer excessive and unbalanced stock levels and, despite a great deal of expediting (and associated costs) are prone to service issues. Such supply chains also experience the bullwhip effect. This occurs due to forecast error being amplified as it cascades up the supply chain and it has the unintended consequence of driving up supply chain costs and service issues, due to supply capacity being unable to meet the spiky demand pattern and the entire chain becoming unstable as a consequence. By contrast, \"demand driven\" supply chains are protected from the need to be buffered from variability and bullwhip by the impact of \"process decoupling' and are thus able to meet planned service levels with significantly lower inventory levels and capacity costs.\n\"Demand driven\" supply chains do use forecasts for the purposes of planning – but not replenishment execution. Forecasts are used for capacity and financial planning which are the main components of \"Sales and Operations Planning\". The accuracy and strategic value of S&OP is actually enhanced when supply chains are \"demand driven\" because they are less prone to unplanned capacity utilisation, \"fire fighting\" and focusing upon resolving current performance issues (i.e.. inventory and service). \"Demand driven\" supply chains also use forecasts for Event Management (e.g., stock build for anticipated events) when postponement strategies are not an option.\nDespite academics having, for many years, written a great deal about the benefits of driving supply chains with demand (e.g.. Forrester 1958, 1961 - \"Industrial Dynamics\"; Burbidge 1983 - \"5 Golden Rules for Avoiding Bankruptcy\"; Christopher & Towill 1995), only since 2002 have 'demand driven' concepts begun to be adopted by supply chain management software providers and industry. (e.g..Lean Planning, Demand Flow Technology, Demand Driven MRP \nInformation systems.\nInformation about activities and costs is an essential resource for improving value chain performance. Such information is nowadays readily available for the supply chain, due to the widespread implementation of ERP technology (systems such as SAP), and these systems have been instrumental in the transformation of supply chain performance.\nDemand chain IT development has focused on database marketing and CRM systems. Demand driving activities and associated costs are still recorded in an inconsistent manner, mostly on spreadsheets and even then the quality of the information tends to be incomplete and inaccurate.\nRecently, however, marketing resource management systems have become available to plan, track and measure activities and costs as an embedded part of marketing workflows.\nImplementation of MRM systems often reveals process issues that must be tackled, as Gartner have observed\nProcess improvement.\nProcesses in a demand chain are often less well-organised and disciplined than their supply side equivalents, partly due to the absence of an agreed framework for analysing the demand chain process. In 2009, Philip Kotler and Robert Shaw proposed such a framework. Describing it as the \"Idea to Demand Chain\" they say:\nBudget segmentation, targeting and optimization.\nDemand chain budgets for marketing, sales and service expenditure are substantial. Maximising their impact on shareholder value has become an important financial goal for decision makers. Developing a shared language across marketing and finance is one of the challenges to achieving this goal.\nSegmentation is the initial thing to decide. From a strategic finance perspective \"segments are responsibility centers for which a separate measure of revenues and costs is obtained\". From a marketing perspective \"segmentation is the act of dividing the market into distinct groups of buyers who might require separate products and/or marketing mixes\". An important challenge for decision makers is how to align these two marketing and finance perspectives on segmentation.\nTargeting of the budget is the final thing to decide. From the marketing perspective the challenge is how \"to optimally allocate a given marketing budget to various target markets\". From a finance perspective the problem is one of resource and budget allocation \"determining the right quantity of resources to implement the value maximising strategy\".\nOptimization provides the technical basis for targeting decisions. Whilst mathematical optimization theory has been in existence since the 1950s, its application to marketing only began in the 1970s, and lack of data and computer power were limiting factors until the 1990s.\nSince 2000, applying maths to budget segmentation, targeting and optimization has become more commonplace. In the UK the IPA Awards have documented over 1000 cases of modelling over 15 years, as part of their award process. The judging criteria are rigorous and not a matter of taste or fashion. Entrants must prove beyond all reasonable doubt that the marketing is profitable. It enables marketing to be brought centre stage in four important ways:\nFirst, it translates the language of marketing and sales into the language of the boardroom. Finance and profits are the preferred language of the modern executive suite. Marketing and sales strategies have to be justified in terms of their ability to increase the financial value of the business. It provides a bridge between marketing and the other functions.\nSecond, it strengthens demand chain accountability. In Marketing Departments awareness, preference and satisfaction are often tracked as alternative objectives to shareholder value. In Sales Departments, sales promotion spending is often used to boost volumes, even when the result is unprofitable. Optimization modelling can assess these practices and support more rigorous accountability methods.\nThird, it provides a counter-argument to the arbitrary cutting of demand chain budgets. Return on marketing investment models can help demonstrate where financial impact of demand driving activities is positive and negative, and so help support fact-based budgeting.\nFinally, demand-chain profitability modelling encourages a strategic debate. Because long-term cashflow and NPV calculations can show the shareholder value effect of marketing, sales and service, strong arguments can be made for putting the demand chain on an equal footing to the supply chain.", "Engineering,_Manufacturing": 0.9841049314, "qwen": "Yes"}
{"id": "3302845", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=3302845", "title": "Uniform-machines scheduling", "text": "Uniform machine scheduling (also called uniformly-related machine scheduling or related machine scheduling) is an optimization problem in computer science and operations research. It is a variant of optimal job scheduling. We are given \"n\" jobs \"J\"1, \"J\"2, ..., \"Jn\" of varying processing times, which need to be scheduled on \"m\" different machines. The goal is to minimize the makespan - the total time required to execute the schedule. The time that machine \"i\" needs in order to process job j is denoted by \"pi,j\". In the general case, the times \"pi,j\" are unrelated, and any matrix of positive processing times is possible. In the specific variant called \"uniform machine scheduling\", some machines are \"uniformly\" faster than others. This means that, for each machine \"i\", there is a speed factor \"si\", and the run-time of job \"j\" on machine \"i\" is \"pi,j\" = \"pj\" / \"si\".\nIn the standard three-field notation for optimal job scheduling problems, the uniform-machine variant is denoted by Q in the first field. For example, the problem denoted by \" Q||formula_1\" is a uniform machine scheduling problem with no constraints, where the goal is to minimize the maximum completion time. A special case of uniform machine scheduling is identical machine scheduling, in which all machines have the same speed. This variant is denoted by P in the first field.\nIn some variants of the problem, instead of minimizing the \"maximum\" completion time, it is desired to minimize the \"average\" completion time (averaged over all \"n\" jobs); it is denoted by Q||formula_2. More generally, when some jobs are more important than others, it may be desired to minimize a \"weighted average\" of the completion time, where each job has a different weight. This is denoted by Q||formula_3.\nAlgorithms.\nMinimizing the average completion time.\nMinimizing the \"average\" completion time can be done in polynomial time:\nMinimizing the weighted-average completion time.\nMinimizing the \"weighted average\" completion time is NP-hard even on \"identical\" machines, by reduction from the knapsack problem. It is NP-hard even if the number of machines is fixed and at least 2, by reduction from the partition problem.\nSahni presents an exponential-time algorithm and a polynomial-time approximation algorithm for \"identical\" machines.\nHorowitz and Sahni presented:\nMinimizing the maximum completion time (makespan).\nMinimizing the \"maximum\" completion time is NP-hard even for \"identical\" machines, by reduction from the partition problem.\nA constant-factor approximation is attained by the Longest-processing-time-first algorithm (LPT).\nHorowitz and Sahni presented:\nHochbaum and Shmoys presented several approximation algorithms for any number of \"identical\" machines. Later, they developed a PTAS for \"uniform\" machines.\nEpstein and Sgall generalized the PTAS for uniform machines to handle more general objective functions. Let \"Ci\" (for \"i\" between 1 and \"m\") be the makespan of machine \"i\" in a given schedule. Instead of minimizing the objective function max(\"Ci\"), one can minimize the objective function max(\"f\"(\"Ci\")), where \"f\" is any fixed function. Similarly, one can minimize the objective function sum(\"f\"(\"Ci\")).\nMonotonicity and Truthfulness.\nIn some settings, the machine speed is the machine's private information, and we want to incentivize machines to reveal their true speed, that is, we want a truthful mechanism. An important consideration for attaining truthfulness is \"monotonicity\". It means that, if a machine reports a higher speed, and all other inputs remain the same, then the total processing time allocated to the machine weakly increases. For this problem:\nExtensions.\nDependent jobs: In some cases, the jobs may be dependent. For example, take the case of reading user credentials from console, then use it to authenticate, then if authentication is successful display some data on the console. Clearly one task is dependent upon another. This is a clear case of where some kind of ordering exists between the tasks. In fact it is clear that it can be modelled with partial ordering. Then, by definition, the set of tasks constitute a lattice structure. This adds further complication to the multiprocessor scheduling problem.\nStatic versus Dynamic: Machine scheduling algorithms are static or dynamic. A scheduling algorithm is static if the scheduling decisions as to what computational tasks will be allocated to what processors are made before running the program. An algorithm is dynamic if it is taken at run time. For static scheduling algorithms, a typical approach is to rank the tasks according to their precedence relationships and use a list scheduling technique to schedule them onto the processors.\nMulti-stage jobs: In various settings, each job might have several operations that must be executed in parallel. Some such settings are handled by open shop scheduling, flow shop scheduling and job shop scheduling.", "Engineering,_Manufacturing": 0.9999945164, "qwen": "Yes"}
{"id": "3306033", "revid": "125972", "url": "https://en.wikipedia.org/wiki?curid=3306033", "title": "List of former automotive manufacturing plants", "text": "List of former automotive manufacturing plants. The table below lists former automotive industry manufacturing factories and facilities.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "32695878", "revid": "23914831", "url": "https://en.wikipedia.org/wiki?curid=32695878", "title": "Horizontal pitch", "text": "Horizontal pitch (HP) is a unit of length defined by the Eurocard printed circuit board standard used to measure the horizontal width of rack mounted electronic equipment, similar to the rack unit (U) used to measure vertical heights of rack mounted equipment. One HP is wide. A standard 19-inch rack is 95 HP wide of which 84 HP is typically usable. A standard 23-inch rack is 115 HP wide of which 104HP is typically usable.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "47813593", "revid": "125972", "url": "https://en.wikipedia.org/wiki?curid=47813593", "title": "Rule based DFM analysis for forging", "text": "Rule based DFM analysis for forging is the controlled deformation of metal into a specific shape by compressive forces. The forging process goes back to 8000 B.C. and evolved from the manual art of simple blacksmithing. Then as now, a series of compressive hammer blows performs the shaping or forging of the part. Modern forging uses machine driven impact hammers or presses that deforms the work-piece by controlled pressure.\nThe forging process is superior to casting in that the parts formed have denser microstructures, more defined grain patterns, and less porosity, making such parts much stronger than a casting. All metals and alloys are forgeable, but each will have a forgeability rating from high to low or poor. The factors involved are the material's composition, crystal structure and mechanical properties all considered within a temperature range. The wider the temperature range, the higher the forgeability rating. Most forging is done on heated work-pieces. Cold forging can occur at room temperatures. The most forgeable materials are aluminum, copper, and magnesium. Lower ratings are applied to the various steels, nickel, and titanium alloys. Hot forging temperatures range from 93°C (200°F) to 1650°C (3000°F) for refractory metals.\nTypes of forging.\nOpen die forging.\nIn open die forging a cylindrical billet is subjected to upsetting between a pair of flat dies or platens. Under frictionless homogeneous deformation, the height of the cylinder is reduced and its diameter is increased. Forging of shafts, disks, rings etc. are performed using the open die forging technique. Square cast ingots are converted into a round shape by this process. Open die forging is classified into three main types; cogging, fullering and edging.\nClose die forging.\nAlso known as impression die forging, impressions are made in a pair of dies. These impressions are transferred to the work-piece during deformation. A small gap between the dies called flash gutter is provided so that the excess metal can flow into the gutter and form a flash. Flash plays an important role during the deformation of the work-piece inside the die cavity. Due to the high length to thickness ratio of the flash gutter, friction in the gap is very high. Because of this, the material in the flash gap is subjected to high pressure. There is high resistance to flow. This in turn promotes effective filling of the die cavity. In hot forging, the flash cools faster as a result of it being smaller in size. This enhances the resistance of the flash material to deformation resistance. As a result of this, the bulk of work-piece is forced to deform and fill the die cavity more effectively – even intricate parts of the die cavity is filled.\nHot forging.\nHot forging is defined as working a metal above its recrystallization temperature. The main advantage of hot forging is that as the metal is deformed the strain-hardening effects are negated by the recrystallization process.\nCold forging.\nCold forging is defined as working a metal below its recrystallization temperature, but usually around room temperature.\nCategories of tolerances.\nGroup 1.\nLength, width and height tolerances, mismatch tolerances, residual flash (and trimmed flat) tolerances, and pierced hole tolerances.\nGroup 2.\nThickness tolerances and ejector mark tolerances.\nGroup 3.\nStraightness and flatness tolerances and tolerances for centre-to-centre dimensions.\nGroup 4.\nFillet and edge radii tolerances, Burr tolerances, surface tolerances, tolerances on draft angle surfaces, eccentricity tolerances for deep holes, eccentricity tolerances for pierced holes, tolerances on concentric bosses, tolerances for unforged stock, and tolerances for deformation of sheared ends.\nDeviations of forms.\nThe tolerances for lengths, widths, heights, and thicknesses cover IL only the diligences of dimensions, but also the deviations of form which are: a) Out of round, b) Deviations from cylindricity c) Deviations from parallelism, and d) Other deviations from the specified contour. The deviations arc not to exceed the limits given by the tolerances. In extreme cases they may cover the whole fields of tolerances unless other is agreed to between the supplier and purchaser. Where restrictions deviations of form have been agreed upon, this shall be noted on the drawing.\nDesign procedure.\nInformation required by forger.\nIn order to assist the forging supplier to utilize his experience to the best effect, both in designing the dies and tools and in establishing forging inspection procedures, rt is in the purchaser's interest to supply the following\nInformation: a) A finished machined drawing; b) Details and dimensions of machining locations (prior notice should be given of any subsequent changes in these location points) c) Anv other relevant information on machining operations and function of the component.\nPreparation.\nIt is recommended that the drop drawing which should then be submitted forger should prepare the forging to the purchaser for approval, and, if necessary, for joint consultation.\nIn instances where the purchaser wishes to prepare his own fully dimensioned forging drawing, it is no less necessary that the drawing of the finished machined component and the other information referred to above should be made available to the supplier.\nIndication of dimensions on drawings.\nIt is imperative to note that, with the exception concerning draft angle surfaces the tolerances indicated in this standard shall be applied only to those dimensions specifically indicated on the agreed forging drawing.\nFor this reason, the method of indicating dimensions on the forging drawing has a vital bearing on the dimensional control of the forging.\nTolerances for dimensions not shown on the forging drawing may not be taken from the standard but may be determined, if required, only by calculation based on the dimensions and tolerances which are already shown on the agreed forging drawing.\nIndication of tolerances on drawings.\nAll forging drawings should be endorsed, ‘Tolerances conform with IS: 3469 (Part II)-1974 unless otherwise indicated\nFor correct endorsement of forging drawings the following form of presentation of tolerances at the foot of the drawing is recommended:\nCategory: 1.Lengths and overall diameters 2. Widths 3. Heights 4. Mismatch 5. Residual flash and trimmed flat 6. Thickness 7. Straightness 8. Flatness 9. Fillet and edge radii 10. Surfaces\nAny tolerances which are only applicable to specific dimensions shall be indicated on the drawing against the particular dimensions concerned. Ejector mark tolerances and burr tolerances should be shown on the forging drawing against the specific locations. Any special tolerances agreed between the purchaser and the supplier shall be indicated clearly on the forging drawing and shall, wherever possible be entered against the specific dimensions concerned.\nImportance of drawings.\nThe drawing of the forged part which has been accepted by the purchaser is the valid document for inspection of the forged part. This drawing is also the only valid document for tolerances on parts of the forging remaining unmachined\nProcesses.\nThere are many different kinds of forging processes available, however they can be grouped into three main classes: 1. Drawn out: length increases, cross-section decreases 2. Upset: Length decreases, cross-section increases 3. Squeezed in closed compression dies: produces multidirectional flow. Common forging processes include: roll forging, swaging, cogging, open-die forging, impression-die forging, press forging, automatic hot forging and upsetting.\nOpen-die drop-hammer forging.\nOpen-die forging is also known as smith forging. In open-die forging a hammer comes down and deforms the workpieces, which is placed on a stationary anvil. Open-die forging gets its name from the fact that the dies (the working surfaces of the forge that contract the workpiece) do not enclose the workpiece, allowing it to flow except where contacted by the dies. Therefore, the operator needs to orient and position the workpiece to get the desired shape. The dies are usually flat in shape but may have a specially shaped surface for specialized operations; for instance the die may have a round, concave, or convex surface or be a tool to form holes or be a cut-off tool. Open-die forging lends itself to short runs and is appropriate for art smiting and custom work. Other times open-die forging is used to rough shape ingots to prepare it for further operations. This can also orient the grains to increase strength in the required direction.\nImpression-die drop-hammer forging.\nImpression-die forging is also called closed-die forging. In impression-die work metal is placed in a die resembling a mold, which is attached to the anvil. Usually the hammer die is shaped as well. The hammer is then dropped on the workpiece, causing the metal to flow and fill the die cavities. The hammer is generally in contact with the workpiece on the scale of milliseconds. Depending on the size and complexity of the part the hammer may be dropped multiple times in quick succession. Excess metal is squeezed out of the die cavities; this is called flash. The flash cools more rapidly than the rest of the material; this cool metal is stronger than the metal in the die so it helps prevent more flash from forming. This also forces the metal to completely fill the die cavity. After forging the flash is trimmed off.\nIn commercial impression-die forging the workpiece is usually moved through a series of cavities in a die to get from an ingot to the final form. The first impression is used to distribute the metal into the rough shape in accordance to the needs of later cavities; this impression is called edging, fullering, or bending impression. The following cavities are called blocking cavities in which the workpiece is working into a shape that more and more resembles the final product. These stages usually impart the workpiece will generous bends and large fillets. The final shape is forged in a final or finisher impression cavity. If there is only a short run of parts to be done it may be more economical for the die to lack a final impression cavity and rather machine the final features.\nImpression-die forging has been further improved in recent years through increased automation which includes induction heating, mechanical feeding, positioning and manipulation, and the direct heat treatment of parts after forging.\nOne variation of impression-die forging is called flashless forging, or true closed-die forging. In this type of forging the die cavities are completely closed, which keeps the workpiece from forming flash. The major advantage to this process is that less metal is lost to flash. Flash can account for 20 to 45% of the starting material. The disadvantages of this process included: additional cost due to a more complex die design, the need for better lubrication, and better workpiece placement.\nThere are other variations of part formation that integrate impression-die forging. One method incorporates casting a forging preform from liquid metal. The casting this then removed after it is cooled to a solid state, but while still hot. It is then finished in a single cavity die. The flash is trimmed and then quenched to room temperature to harden the part.\nAnother variation follows the same process as outlined above, except the preform is produced by the spraying deposition of metal droplet into shaped collectors (similar to the osprey process).\nClosed-die forging has a high initial cost due to the creation of dies and required design work to make working die cavities. However, it has low reoccurring costs for each part, thus forgings become more economical with more volume. This is one of the major reasons forgings are often used in the automotive and tool industry. Another reason forgings are common in these industrial sectors is because forgings generally have about a 20% higher strength to weight ratio compared to cast or machined parts of the same material.\nDesign of impression-die forgings and tooling.\nForging dies are usually made of high-alloy or tool steel. Dies must be impact resistant, wear resistant, maintain strength at high temperatures, and have the ability to withstand cycles of rapid heating and cooling. In order to produce a better, more economical die the following rules should be followed:\n1. The dies should part along a single, flat plane if at all possible, If not the parting plan should follow the contour of the part. 2. The parting surface should be a plane through the center of the forging and not near an upper or lower edge. 3. Adequate draft should be provided; a good guideline is at least 3° for aluminum and 5° to 7° for steel 4. Generous fillets and radii should be used 5. Ribs should be low and wide 6. The various sections should be balanced to avoid extreme difference in metal flow 7. Full advantage should be taken of fiver flow lines 8. Dimensional tolerances should not be closer than necessary. The dimensional tolerances of a steel part produced using the impression-die forging method are outlined in the table below. The dimensions across the paring plane are affected by the closure of the dies, and are therefore dependent die wear and the thickness of the final flash. Dimensions that are completely contained within a single die segment or half can be maintained at a significantly greater level of accuracy. A lubricant is always used when forging to reduce friction and wear. It is also used to as a thermal barrier to restrict heat transfer from the workpiece to the die. Finally the lubricant acts as a parting compound to prevent the part from sticking in one of the dies.\nPress forging.\nPress forging is variation of drop-hammer forging. Unlike drop-hammer forging, press forges work slowly by applying continuous pressure or force. The amount of time the dies are in contact with the workpiece is measured in seconds (as compared to the milliseconds of drop-hammer forges). The main advantage of press forging, as compared to drop-hammer forging, is its ability to deform the complete workpiece.\nDrop-hammer forging usually only deforms the surfaces of the workpiece in contact with the hammer and anvil; the interior of the workpiece will stay relatively undeformed. There are a few disadvantages to this process, most stemming from the workpiece being in contact with the dies for such an extended period of time. The workpiece will cool faster because the dies are in contact with workpiece; the dies facilitate drastically more heat transfer than the surrounding atmosphere. As the workpiece cools it becomes stronger and less ductile, which may induce cracking if deformation continues. Therefore, heated dies are usually used to reduce heat loss, promote surface flow, and enable the production of finer details and closer tolerances. The workpiece may also need to be reheated.\nPress forging can be used to perform all types of forging, including open-die and impression-die forging. Impression-die press forging usually requires less draft than drop forging and has better dimensional accuracy. Also, press forgings can often be done in one closing of the dies, allowing for easy automation.\nUpset forging.\nUpset forging increases the diameter of the workpiece by compressing its length. Based on number of pieces produced this is the most widely used forging process. Upset forging is usually done in special high speed machines; the machines are usually set up to work in the horizontal plane to facilitate the quick exchange of workpieces from one station to the next. The initial workpiece is usually wire or rod, but some machines can accept bars up to 25 cm (10 in.) in diameter. The standard upsetting machine employs split dies that contain multiple cavities. The dies open enough to allow the workpiece to move from one cavity to the next; the dies then close and the heading tool, or ram, then moves longitudinally against the bar, upsetting it into the cavity. If all of the cavities are utilizes on every cycle then a finished part will be produced with every cycle, which is why this process is ideal for mass production.\nA few examples of common parts produced using the upset forging process are engine valves, couplings, bolts, screws, and other fasteners.\nThe following three rules must be followed when designing parts to be upset forged:\nAutomatic hot forging.\nThe automatic hot forging process involves feeding mill-length steel bars (typically 7 m or 24 ft long) into one end of the machine at room temperature and hot forged products emerge from the other end. This all occurs very quickly; small parts can be made at a rate of 180 parts per minute (ppm) and larger can be made at a rate of 90 ppm. The parts can be solid or hollow, round or symmetrical, up to 6 kg (12 lbs), and up to 18 cm (7 in.) in diameter. The main advantages to this process are its high output rate and ability to accept low cost materials. Little labor is required to operate the machinery. There is no flash produced so material savings are between 20 - 30% over conventional forging. The final product is a consistent 1050 °C (1900 °F) so air cooling will result in a part that is still easily machinable (the advantage being the lack of annealing required after forging). Tolerances are usually ±0.3 mm (±0.012 in.), surfaces are clean, and draft angles are 0.5 to 1°. Tool life is nearly double that of conventional forging because contact times are on the order of 6/100 of a second.\nThe downside to the process is it only feasible on smaller symmetric parts and cost; the initial investment can be over $10 million, there large quantities are required to justify this process. The process starts by heating up the bar to 1200 to 1300 °C (2200 to 2350 °F) in less than 60 seconds using high power induction coils. It is then descaled with rollers, sheared into blanks, and transferred several successive forming stages, during which it is upset, preformed, final forged, and pierced (if necessary). This process can also be couple with high speed cold forming operations. Generally, the cold forming operation will do the finishing stage so that the advantages of cold-working can be taken advantage of, while maintaining the high speed of automatic hot forging.\nExamples of parts made by this process are: wheel hub unit bearings, transmission gears, tapered roller bearing races, stainless steel coupling flanges, and neck rings for LP gas cylinders. Manual transmission gears are an example of automatic hot forging used in conjunction with cold working.\nRoll forging.\nRoll forging is a process where round or flat bar stock is reduced in thickness and increased in length. Roll forging is performed using two cylindrical or semi-cylindrical rolls, each containing or more shaped grooves. A bar is inserted into the rolls and when it hits a stop the rolls rotate and the bar is progressively shaped as it is rolled out of the machine.\nThe workpiece is then transferred to the next set of grooves or turned around and reinserted into the same grooves. This continues until the desired shape and size is achieved. The advantages of this process is there is no flash and it imparts a favorable grain structure into the workpiece. Examples of products produced using this method include axles, tapered levers and leaf springs.\nNet-shape and near-net-shape forging.\nThis process is also known as precision forging. This process was developed to minimize cost and waste associated with post forging operations. Therefore, the final product from a precision forging needs little to no final machining. Cost savings are gained from the use of less material, and thus less scrap, the overall decrease in energy used, and the reduction or elimination of machining. Precision forging also requires less or a draft, 1° to 0°. The downsize of this process is its cost, therefore it is only implemented if significant cost reduction can be achieved.\nEquipment.\nThe most common thought of forging equipment is the hammer and anvil. The principles behind the hammer and anvil are still used today in drop-hammer equipment. The principle behind the machine is very simple, raise the hammer and then drop it or propel it into the workpiece, which rests on the anvil. The main variations between drop-hammers is in the way that the hammer is powered; the most common being air and steam hammers. Drop-hammers usually operate in the vertical position. The main reason for this is because excess energy (energy that isn't used to deform the workpiece) that isn't released as heat or sound needs to be transmitted to the foundation. Moreover, a large machine base is needed to absorb the impacts.\nTo overcome some of the shortcomings of the drop-hammer the counterblow machine or impactor is used. In a counterblow machine both the hammer and anvil move and the workpiece is held between them. Here excess energy becomes recoil. This allows for the machine to work horizontally and consist of a smaller base. Other advantages include less noise, heat and vibrations. It also produces a distinctly different flow pattern. Both of these machines can be used for open die or closed die forging. A forging press, often just called a press, is used for press forging.\nThere are two main types: mechanical and hydraulic presses. Mechanical presses function by using cams, cranks or toggles to produce a preset (a predetermined force at a certain location in the stroke) and reproducible stroke. Due to the nature of this type of system difference forces are available at different stroke positions. Mechanical presses are faster than their hydraulic counterparts (up to 50 strokes per minute). Their capacities range from 3 to 160 MN (300 to 18,000 tons). Hydraulic presses use fluid pressure and a piston to generate force. The advantages of a hydraulic press over a mechanical press is its flexibility and greater capacity. The disadvantages are that they are slower, larger and more costly to operate. The roll forging, upsetting, and automatic hot forging processes all use specialized machinery.", "Engineering,_Manufacturing": 0.9999859333, "qwen": "Yes"}
{"id": "47813958", "revid": "45382375", "url": "https://en.wikipedia.org/wiki?curid=47813958", "title": "Rule-based DFM analysis for direct metal laser sintering", "text": "Rule based DFM analysis for direct metal laser sintering. Direct metal laser sintering (DMLS) is one type of additive manufacturing process that allows layer by layer printing of metal parts having complex geometries directly from 3D CAD data. It uses a high-energy laser to sinter powdered metal under computer control, binding the material together to create a solid structure. DMLS is a net shape process and allows the creation of highly complex and customized parts with no extra cost incurred for its complexity.\nDMLS is being used to fabricate complex metal parts that are difficult to do so using traditional manufacturing processes thus gives immense freedom to the designer while designing the component. However, there are certain Design for Manufacturability (DFM) considerations that should be taken care of while designing the parts to be printed. DFM provides guidance to the design team in making the product structure more compliant to the given manufacturing process. It removes the wall between the designing and manufacturing phases of product development thus enables designers to take advantages of all the inherent costs and other benefits available in the manufacturing process. The early considerations of DFM principles and guidelines can lead to significant cost and time cutting in the final development of the product. Some of the common guidelines for DMLS are:\nSize.\nThe size of the part that can be printed depends upon the printer that is being used. With the current technology a maximum build size of 228 X 228 X 304 mm can be achieved. Hence, the size of the part to be printed should be within required dimensions. DMLS has a minimum sintering width (depends on laser diameter) varying from 0.6 mm to 0.9 mm. This defines the minimum external feature size of the part and thus the design with any external features having smaller dimensions must be avoided.\nAccuracy.\nThe accuracy and surface roughness of the part depends on the powder grain size ranging between 50 μm to 100 μm. The layer thickness which lies between 0.02 mm and 0.05 mm determines the resolution in the vertical direction. Therefore, the regions of the parts which require high accuracy should be designed with planned allowance of 0.1 mm to 0.5 mm and secondary finishing and/or machining operations should then be used to achieve the required accuracy.\nOverhangs.\nIn DMLS, powder bed supports the parts and keep them held in place. However, support structures are explicitly required for most of the downward facing surfaces that make an angle less than 45 degrees with the powder bed. This is because powder bed alone is not sufficient enough to hold the liquid phase of the metal that is created when laser is scanning the powder. Support structures are also required to restrict curling/warping of the melted powder due to high-temperature gradients. The overhangs having angles less than 45 degrees should be avoided if possible at the design stage. The main advantage of this is to reduce material usage and the post processing requirement of removing support structures from the designed components.\nHeight.\nThe total number of layers required to build the whole part is directly proportional to the height of the part measured along the build direction. Every layer of the part to be printed requires tightly laying compacted thin layer of powdered material using roller, tracing of laser according to the 3D data fed to the machine in the horizontal plane and incremental lowering of powder bed for the successive layer to be laid. These processes require a significant amount of time thus redesigning the product for smaller heights may save manufacturing time greatly. The build orientation should be such that the height of the part should be least along the build direction.\nAnisotropy.\nThe main direction of heat flow which is generated by the laser at the top is along the build direction due to the fact that powder bed lying at the bottom is the major heat sink. The layered addition of material and the directional heat flow in DMLS lead to the growing of microstructural grains along the build direction leading to anisotropic properties. The structure printed through DMLS has weaker properties along the build direction. This anisotropy can be removed using heat treatment methods but they are highly energy intensive and costly processes. Hence, it is advisable to consider the anisotropy in the very beginning of designing such structural parts and the direction of largest stress in the structure should lie in the horizontal plane.\nComplexity.\nBeing an additive manufacturing technique, DMLS doesn't incur any extra cost for the complexity of the part. The build volume along with the number of layers is what determines the production cost and time. DMLS eliminates the need for tool production however such technologies are impervious to economies of scale. Therefore, it is recommended to design parts with least amount of superfluous volumes, building only the relevant geometries. Furthermore, the parts should be designed to avoid assembly requirements because printing sub-assembly with intricate geometries is now possible.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "47836583", "revid": "73985", "url": "https://en.wikipedia.org/wiki?curid=47836583", "title": "Peening", "text": "In metallurgy, peening is the process of working a metal's surface to improve its material properties, usually by mechanical means, such as hammer blows, by blasting with shot (shot peening), focusing light (laser peening), or in recent years, with water column impacts (water jet peening) and cavitation jets (cavitation peening). With the notable exception of laser peening, peening is normally a cold work process tending to expand the surface of the cold metal, thus inducing compressive stresses or relieving tensile stresses already present. It can also encourage strain hardening of the surface metal.\nResidual stress.\nPlastic deformation from peening induces a residual compressive stress in a peened surface, along with tensile stress in the interior. This stress state resembles the one seen in toughened glass, and is useful for similar reasons.\nSurface compressive stresses confer resistance to metal fatigue and to some forms of corrosion, since cracks will not grow in a compressive environment. The benefit comes at the expense of higher tensile stresses deeper in the part. However, the fatigue properties of the part will be improved, since the stresses are normally significantly higher at the surface in part due to surface imperfections and damage.\nWork hardening.\nCold working also serves to harden the material's surface. This makes cracks less likely to form at the surface and provides resistance to abrasion. When a metal undergoes strain hardening its yield strength increases but its ductility decreases. Strain hardening actually increases the number of dislocations in the crystal lattice of the material. When a material has a great number of dislocations, plastic deformation is hindered, and the material will continue to behave in an elastic way well beyond the elastic yield stress of the non-strain hardened material.\nResidual strain / stretching.\nPlastic deformation from peening can be useful in stretching the surface of an object.\nOne common use of this peening (stretching) process can be seen in the auto repair and auto custom fabrication industries where manual or machine assisted peening is used to stretch thin sheet metal to create curved surfaces. The manual method uses a hand held peening hammer and is a form of planishing. There are also machine assisted methods that use a version of a power hammer to peen the sheet metal.\nAnother use of the peening process is to flatten sheet metal and is specifically used as a primary technique to flatten steel belts used in industrial conveying and pressing operations. In this process a steel belt that has a cross curvature can be flattened by peening the concave surface to stretch it and thereby removing the cross-curvature by equalizing the surface length across the belt between the previously concave and convex surfaces. The shot peening of steel belts is usually achieved by using specialized equipment and special peening shot.\nWhen peening is used to induce residual stress or work-harden an object, care needs to be taken with thin parts not to stretch the work-piece. Where stretching is unavoidable then allowances may need to be made in the part design or process application.\nUse with welding.\nHand peening may also be performed after welding to help relieve the tensile stresses that develop on cooling in the welded metal (as well as the surrounding base metal). The level of reduction in tensile stress is minimal and only occurs on or near to the weld surface. Other methods, like heat spots (if applicable), help reduce residual tensile stresses. Peening will induce a higher hardness into the weld and this is something that should be avoided. For this reason, peening is not normally accepted by the majority of codes, standards or specifications. Any peening that is carried out on a weld should have been carried out on the weld procedure qualification test piece.\nThe welding procedure qualification test piece replicates all of the essential variables that will be used in production welding. If the weld is peened during the qualification of a welding procedure, the subsequent mechanical testing of the procedure qualification test piece will demonstrate the mechanical properties of the weld. These mechanical properties must, as a minimum, match the mechanical properties of the materials that have been welded together. If they do not, the procedure has failed and the welding procedure is not acceptable for use in production welding.\nSharpening blades.\nScythe and sickle blades have traditionally been sharpened by occasional peening followed by frequent honing in the field during use. A blade can be sharpened by reforming the malleable steel to create an edge profile that can then be honed. Nicks and cuts to the blade edge can be worked out of the blade by peening and a new edge profile then formed for honing.\nBlades can be free-peened using various designs of peening anvils, or worked on a peening jig. A peening jig may have interchangeable caps that set different angles: a coarse angle can be set first about back from the edge, and a fine angle is then set on the edge, leaving an edge that lends itself to being easily honed. The blade can then be honed using progressively finer honing stones until it is ready for use.\nHistory.\nDuring construction of Barker Dam hydroelectric facilities in Colorado between 1908 and 1910, workers discovered that striking welds while they were still warm improved their strength.\nThe first published article about peening was written in Germany in 1929, and was specifically about shot peening. The first patent for shot peening was taken out in Germany in 1934 but was never commercially implemented. Independently in 1930, a few engineers at Buick noticed that \"shot blasting\" (as it was originally termed) made springs resistant to fatigue. This process was then adopted by the automotive industry. Zimmerli first published a report in 1940. John Almen did more research, and during World War 2 introduced it to the aircraft industry.\nBy 1950, peening became an accepted process and was being included in engineering literature. In the same year, peen forming was invented to form the wing skin of the Super Constellation aircraft.\nIn the early 1970s, peening experienced a major innovation when researchers such as Allan Clauer at Battelle labs in Columbus, Ohio applied high-intensity laser beams onto metal components to achieve deep compressive residual stresses, which they patented as Laser Shock Peening, and became known as laser peening in the late 1990s, when it was first applied to gas-fired turbine engine fan blades for the U.S. Air Force.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "11127382", "revid": "44505775", "url": "https://en.wikipedia.org/wiki?curid=11127382", "title": "Belt problem", "text": "The belt problem is a mathematics problem which requires finding the length of a crossed belt that connects two circular pulleys with radius \"r\"1 and \"r\"2 whose centers are separated by a distance \"P\". The solution of the belt problem requires trigonometry and the concepts of the bitangent line, the vertical angle, and congruent angles.\nSolution.\nClearly triangles ACO and ADO are congruent right angled triangles, as are triangles BEO and BFO. In addition, triangles ACO and BEO are similar. Therefore angles CAO, DAO, EBO and FBO are all equal. Denoting this angle by formula_1 (denominated in radians), the length of the belt is\nThis exploits the convenience of denominating angles in radians that the length of an arc = the radius × the measure of the angle facing the arc.\nTo find formula_1 we see from the similarity of triangles ACO and BEO that\nFor fixed \"P\" the length of the belt depends only on the sum of the radius values \"r\"1 + \"r\"2, and not on their individual values.\nPulley problem.\nThere are other types of problems similar to the belt problem. The pulley problem, as shown, is similar to the belt problem; however, the belt does not cross itself. In the pulley problem the length of the belt is\nwhere \"r\"1 represents the radius of the larger pulley, \"r\"2 represents the radius of the smaller one, and:\nApplications.\nThe belt problem is used in the design of aeroplanes, bicycle gearing, cars, and other items with pulleys or belts that cross each other. The pulley problem is also used in the design of conveyor belts found in airport luggage belts and automated factory lines.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "11136953", "revid": "9710872", "url": "https://en.wikipedia.org/wiki?curid=11136953", "title": "Manufacturing Technologies Association", "text": "The Manufacturing Technologies Association (MTA) is a UK trade association representing the manufacturing technologies industry. The MTA sits at the core of the engineering based manufacturing sector and as an association works tirelessly to ensure member companies are as commercially successful as possible.\nThe association's key activities include:\n- Representing engineering based manufacturing and supporting the advanced engineering sector through lobbying, media contact and networking.\n- Providing relevant and specific industry intelligence \n- Encouraging talent through funding and support for workplace training and education initiatives in schools, colleges and universities.\n- Delivering the UK's only major exhibition focused on manufacturing technologies – MACH (owned and organised by the MTA)\nMembership of the MTA is open to companies involved with the manufacturing technologies sector and end users of such technology.\nFunction.\nThe MTA represents UK companies, their associates and affiliates who drive UK manufacturing technology, innovation and quality.\nThe website contains a member & product directory by geographic position. It also provides information and statistics on the economic health of the British manufacturing markets.\nMTA is the owner and organiser of the UK's premier manufacturing event - the MACH exhibition, a week-long event held biennially in April at the NEC.\nThe types of manufacturing technologies covered by the organisation, and the exhibition, include:\nHistory.\nThe original Machine Tools Trades Association (MTTA) was formed in 1919, becoming the Machine Tools Technologies Association. Since its formation the association has evolved into a trade body with a global support network, promoting internationally competitive trade in manufacturing technologies.\nStructure.\nThe MTA is based in London, with close contact with the British Government through the Department of Business Innovation and Skills (BIS) (United Kingdom), CBI and UK Trade & Investment.\nThe association's offices are located on \"Bayswater Road\" (A402) next to Lancaster Gate tube station.\nThe association also provides a secretariat service to the Federation of British Hand Tool Manufacturers (FBHTM), and the MTA Tooling Group, formerly the British Hard Metal and Engineers' Cutting Tools Association (BHECTA).", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "28589541", "revid": "35936988", "url": "https://en.wikipedia.org/wiki?curid=28589541", "title": "Fay automatic lathe", "text": "The Fay automatic lathe was an automatic lathe tailored to cutting workpieces that were mounted on centers (tools with pointed ends to accurately position a center-drilled workpiece about an axis, either directly or by using a mandrel). It could also do chucking work (feeding of unformed blanks or pieces of stock from a magazine to be automatically gripped by the machine for turning). Examples of workpieces included automotive steering knuckles and transmission gears, and such work done on mandrels as flanges, disks, and hubs. The machine tool was developed by F.C. Fay of Philadelphia and improved by Otto A. Schaum. It was originally manufactured by the Fay & Scott Machine Shop. James Hartness acquired manufacturing rights on behalf of the Jones & Lamson Machine Company and manufactured an improved version, developed under the management of Ralph Flanders.\nIn 1937 Roe, writing for the American Society of Mechanical Engineers, framed the importance of the Fay automatic lathe to the capabilities of machine tools by saying that, \"This machine does for the engine lathe what Spencer did for the old hand-operated turret lathe.\" These machines took an entire class of turned work formerly requiring an operator to execute the series of movements necessary to shape a piece of metal (manual control) and allowed the same work to be done automatically. This step forward in automation lowered a manufacturer's unit expense per part by reducing labor costs. Today, numerically controlled (CNC) machine tools such as turning centers, turn-mills, and rotary transfer machines have largely supplanted cam-operated automatics.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "32050260", "revid": "35498457", "url": "https://en.wikipedia.org/wiki?curid=32050260", "title": "Cloud manufacturing", "text": "Cloud manufacturing (CMfg) is a new manufacturing paradigm developed from existing advanced manufacturing models (e.g., ASP, AM, NM, MGrid) and enterprise information technologies under the support of cloud computing, Internet of Things (IoT), virtualization and service-oriented technologies, and advanced computing technologies. It transforms manufacturing resources and manufacturing capabilities into manufacturing services, which can be managed and operated in an intelligent and unified way to enable the full sharing and circulating of manufacturing resources and manufacturing capabilities. CMfg can provide safe and reliable, high quality, cheap and on-demand manufacturing services for the whole lifecycle of manufacturing. The concept of manufacturing here refers to big manufacturing that includes the whole lifecycle of a product (e.g. design, simulation, production, test, maintenance). \nThe concept of Cloud manufacturing was initially proposed by the research group led by Prof. Bo Hu Li and Prof. Lin Zhang in China in 2009.\n Related discussions and research were conducted hereafter, and some similar definitions (e.g. Cloud-Based Design and Manufacturing (CBDM).\n) to cloud manufacturing were introduced.\nCloud manufacturing is a type of parallel, networked, and distributed system consisting of an integrated and inter-connected virtualized service pool (manufacturing cloud) of manufacturing resources and capabilities as well as capabilities of intelligent management and on-demand use of services to provide solutions for all kinds of users involved in the whole lifecycle of manufacturing.\nTypes.\nCloud Manufacturing can be divided into two categories.\nIn CMfg system, various manufacturing resources and abilities can be intelligently sensed and connected into wider Internet, and automatically managed and controlled using IoT technologies (e.g., RFID, wired and wireless sensor network, embedded system). Then the manufacturing resources and abilities are virtualized and encapsulated into different manufacturing cloud services (MCSs), that can be accessed, invoked, and deployed based on knowledge by using virtualization technologies, service-oriented technologies, and cloud computing technologies. The MCSs are classified and aggregated according to specific rules and algorithms, and different kinds of manufacturing clouds are constructed. Different users can search and invoke the qualified MCSs from related manufacturing cloud according to their needs, and assemble them to be a virtual manufacturing environment or solution to complete their manufacturing task involved in the whole life cycle of manufacturing processes under the support of cloud computing, service-oriented technologies, and advanced computing technologies.\nFour types of cloud deployment modes (public, private, community and hybrid clouds) are ubiquitous as a single point of access.\nResources.\nFrom the resource’s perspective, each kind of manufacturing capability requires support from the related manufacturing resource. For each type of manufacturing capability, its related manufacturing resource comes in two forms, soft resources and hard resources.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "32057477", "revid": "43222388", "url": "https://en.wikipedia.org/wiki?curid=32057477", "title": "Ifco tray", "text": "IFCO trays (also known as RPCs (the abbreviation for reusable packaging containers), or reusable containers, or reusable crates) are a type of reusable packaging for transporting fresh food produce. IFCO SYSTEMS is the name of the company that first developed a pooling service for reusable plastic trays for fresh produce in 1992, when the company was founded in Pullach, Germany. IFCO is the acronym for International Food Container Organization. \nThey are attractive for environmental reasons due to their ease of reuse, their capability of being stacked when full of produce in many different configurations and that they can be flattened when empty for compact return to producers/shippers/growers or for storage purposes.\nReusable packaging.\nThe IFCO RPCs and trays are used for transporting perishable products and are available in different designs customized to the requirements of the produce. There are IFCO trays for fresh food, fruit and vegetables, bananas, baked goods, eggs, dairy, convenience foods, meat and fish.\nZero Waste.\nWhen the IFCO trays reach the end of their service life and can no longer be repaired, they are granulated and made into new IFCO RPCs. The raw material stream for the IFCO reusable crates is fully traceable. The company uses 100% of the available material from the broken or end-of-use crates. The IFCO trays generally have a life span of more than 10 years, before they are made into new crates. There is no packaging waste and there is a 100% material reutilization.  \nPooling.\nIFCO trays are only available through the IFCO pooling service. Customers of the service share the reusable containers in a continuous closed loop. IFCO SYSTEMS refer to this pooling loop as the IFCO SmartCycle.\nIFCO supplies the reusable containers to farmers and producers of fresh produce and perishable items. Customers that use the SmartCycle are supplied with clean, sanitized IFCO RPCs at harvest or at the end of the production cycle. The produce is shipped or transported in the reusable plastic containers on pallets to the retailers, where the produce generally goes on display at the Point of Sale in the IFCO trays. This reduces the number of touchpoints with the produce and aims to reduce the potential for produce damage and waste, extending the shelf life of the fresh food produce in the process.  \nWhen empty and used, the reusable containers are recovered and returned to the IFCO wash centers, where they are checked, repaired (if necessary), washed, and then supplied to customers and used again.  \nCircular economy model.\nThe IFCO pooling service of RPCs and material reutilization is based on the circular economy model, which promotes the reuse, sharing, repair, refurbishment, remanufacturing and recycling within a closed-loop system in order to avoid waste and reduce the environmental impact of industrial designs.   \nSustainability.\nCompared to disposable products and packaging, reusable containers help reduce the overall environmental impact of the fresh grocery supply chain.  \nAs the IFCO trays can be folded compactly, they require less space in the reverse logistics as they are mainly the same size and are therefore compatible when folded. More IFCO RPCs can be stacked in trucks and in storage, saving food miles, energy consumption and storage costs.  \nCradle to Cradle Design.\nThe IFCO European line of Lift Lock reusable plastic containers (RPCs) are the first and only reusable food packaging containers to be awarded Cradle to Cradle Certified® (Version 3.1) at the Silver level by the independent non-profit Cradle to Cradle Products Innovation Institute, which is based on the Cradle to Cradle design philosophy of Michael Braungart and William McDonough. These IFCO trays were awarded Gold for Material Reutilization. \nFood safety.\nThe IFCO RPCs are washed and sanitized to food-grade quality after each use. The washing process is independently audited. \nCompany history.\nFounded in 1992 in Germany, the company originally focused on Europe and expanded into the US market in 2003, when it launched the first Black RPC.  \nIFCO serves customers in over 50 countries, has offices in over 30 countries, 89 service centers and employs around 1,100 people. The company has a pool of over 314 million reusable plastic containers, which are used in over 1.7 billion shipments of fresh produce every year. Over 14,000 producers use the IFCO trays, and over 300 retailers.  \nIFCO is an independent company since its acquisition by Triton and Abu Dhabi Investment Authority (ADIA) in May 2019 from the Brambles company who had owned IFCO since 2011. \nInnovation.\nIFCO Systems has filed a total of 1,174 patents for the IFCO reusable plastic containers and pooling system. \nSlogan.\nThe company slogan is: “A better supply chain serves us all. Let’s eat.” \nControversy.\nTheir adoption has generated controversy between developed countries which are consumers of produce and developing countries which are producers, primarily due to the cost of using the trays as opposed to using locally produced containers. In particular, many developing countries lack the capital-intensive infrastructure to develop and support the hi-technology plastic molding machinery necessary to produce the returnable trays. Analysis continues to compare the relative benefits of reusable trays, which require a full cycle (use, cleaning and return) versus one-time-use disposable containers which do not require return to the shipper, but instead are disposed of after one use. Disposable containers create a waste-disposal burden on recipients, while the returnable containers burden producers who must purchase containers and arrange for a return cycle.", "Engineering,_Manufacturing": 0.9998113513, "qwen": "Yes"}
{"id": "32063688", "revid": "30035619", "url": "https://en.wikipedia.org/wiki?curid=32063688", "title": "US error coins", "text": "US error coins are error coins produced by the US government. There are three categories of error coins as provided by the American Numismatic Association. Metal usage and striking errors referred to widely as planchet errors, die errors, and mint striking errors. This does not include the varieties that the US Mint has issued over the years.\nSince the inception of coin collecting there has been much controversy over what constitutes a true mint error. An organization of coin collectors named the Combined Organizations of Numismatic Error Collectors of America (CONECA) was created that specifically deals with mint errors.\nPlanchet errors.\nA planchet is produced by punching blanks in sheet metal stock specially made for the types of mint blanks required. After the blanks are punched they are rolled on the edge placing an upset needed for the minting process. The blanks are then washed and annealed making them ready for the minting process\nThere are several types of planchet errors that include: improper alloy, wrong stock, imperfect blank, and lamination.\nA planchet error may be caused by an improper alloy mixture. Improper alloy mixtures occur when the sheet stock contains uneven layers of the metals intended for the type of coin that is produced. A result of improper layers of metals is a coin produced without an intended surface layer of nickel. A dime or quarter without the nickel layer will contain only the copper alloy mixture.\nA planchet error can be caused by using a blank intended for a different denomination or wrong stock. The result of using a blank intended for another denomination is the minting of the intended obverse and reverse on the wrong stock.\nA planchet error also refers to many types of issues where an imperfect blank has been used. Pieces of the blank might be missing causing a half moon to be missing from the coin. Collectors denote missing parts of the planchet as \"clipped planchets.\" A dirty or oily blank may cause the details of the coin to become dull or even missing. A piece of debris may find its way into the dies causing a series of lines to be minted on the surface of the coin.\nA planchet may be in a state that causes peeling on the surface of the coin. The peeling of any part of the surface of a coin is known as a lamination error.\nBelow is a lamination error on a Jefferson nickel.\nDie errors.\nDie errors are caused by the mint dies wearing down over time or dies that have not been prepared identical to others that have been replaced. The result of preparing a set of new dies improperly from the original hub results in coin errors such as doubling, extra details, or missing details on the surface of the coin.\nA die break is caused when the mint die suffers a crack and this crack feature is transposed onto the coins in the minting process. Coins minted with a die break have a thin line or lines that are raised running across the surface of the coin. Below is a photograph of a 1954-S Jefferson nickel with a die crack along the top of the portrait of Jefferson. \nA die break can create coins that have deep impressions in a coin that is filled in with metal. The coin shows a raised patch of metal were the break occurred. This type of error is commonly known as a \"cud\" error. \nGouges in coins caused by flaws in dies, and die polishing mistakes resulting in coins minted with surface indentations, or polishing lines.\nDies that are damaged and used in the minting process also create errors resulting in coins having die chips embedded in the surface of the coin.\nA die clash occurs when a planchet is not fed into the collar that holds the coin in place for the minting process. The two dies meet and each carries away part of the design embedded on the die. Coins minted using these dies cause coins to be minted with parts of the reverse design on the obverse or parts of the obverse on the reverse of the coin. \nDie rotations cause coins to be minted with the reverse or obverse of the coin partially or fully rotated. A die rotation occurs when the dies become loose and they then turn.\nWhen a mint worker polishes a die to remove a die clash or some other defect there may be instances where a part of the design is removed. The 3-legged Buffalo nickel was the direct result of die polishing and the removal of a leg. The 1970 Lincoln cent with the raised 7 is also the result of die polishing.\nBefore 1990, all US coin dies were subject to mint mark errors resulting from the preparation of the dies. The mint mark was hammered into the die manually sometimes causing a die to have a doubling. In the minting process this would create a series of coins with a distinct of slight doubling of the mint mark. Millions of these errors can be located on the internet for sale and are referred to as RPM’s\nDoubled dies.\nDoubled die coins are mainly created by a defective hub which is used to create many dies for the minting process. Collectors classify doubled dies as DDO (doubled die obverse coins), DDR (doubled die reverse) and OMM (over mint mark).\nThe over mint mark is created when a one date and mint mark is punched over another date, part of a date, or mint mark. These coins are generally restricted to the early minting process of coins dating before the turn of the century.\nThe DDO and DDR errors are related to any part of the coin that shows a distinct doubling. Pictured below is a 1969-S doubled die Lincoln cent.\nMint striking errors.\nCollectors and organizations dedicated to collecting coins regard mint striking errors as those that have been created by the minting process. Mint striking errors are caused by the collar moving, cracking, or not being present in the minting process. The collar is a third die that actually holds the coin in place in the minting process. It is the collar that imprints the lettering on a coin, such as the lettering on the Presidential dollars.\nStriking a coin with debris causes an indentation on the coin or the actual debris stamped into the coin.\nIn order to mint any US coin a retaining collar is used to keep the coin in place while it is pressed between the dies. If the retaining collar breaks or is missing, the coin is struck so that the metal of the planchet is actually expanded outward producing a larger version of the coin with most of the details present. This error is known as a broad struck error.\nA coin that has been struck out of the collar and has double details such as two partial portraits, one normal and one that is overlapping and extending outside the normal circumference of the coin is denoted as a double striking error.\nA brockage results when a coin is stuck in the collar and another planchet enters the collar and is pressed against the coin already minted. The details of the coins produced have the appearance of mirror images of the obverse and reverse.\nA die cap is a coin that has been stamped a number of times and has the appearance of a soda cap. Metal flows around the side of the coin and the portrait appears deep in the coin.\nVariations.\nVariations are not mint errors in the technical sense. Variations in coins are caused by creating hubs and dies that are not exactly the same resulting in dates that can be compared as large to small, wide to thin etc. These die variations resulted in the 1960 large- and small-dated Lincoln cent, and the 1982 large- and small-dated series both in copper and copper-zinc cents minted.\nBelow are photographs of two Brilliant Uncirculated Jefferson nickels. Note that these are variations of dies used to mint the 1970-D Jefferson nickels. The die variation is clearly evident with the placement of the D in two different locations, one closest to the 1970 and the other closest to the rim of the coin.\nThere are some variations created by the mint site using different die sets. The best case of the mint using different die sets is the variation of the letters AM on the Lincoln cent. The AM letters are either touching or are distinctly apart in some Lincoln cents minted in 1998, 1999, 2000, and perhaps others to be discovered. Normally, the wide AM design is reserved for the Lincoln proof designs. Below is a photograph of a wide AM Lincoln cent.\nUnclassified error coins.\nUnclassified error coins are those that are difficult to categorize. Below are two unclassified error, one with the date flattened in a 1998 Jefferson nickel and another Jefferson nickel with a recessed S. \nCounter stamped coins.\nCounter stamped coins have a long history in the early days of minted coins. Many companies used counter stamping as a method to advertise their company. There are thousands of counter stamped coins some of which carry little value while others command values in the thousands. In any case, these coins were changed after leaving the mint, and are not true error coins.\nInitials were sometime cut into coins. Some of these coins have been classified as \"love tokens\" having the initials of the person who counter stamped the coin. Below is a counter stamped Lincoln cent with a number 2 in a bar shape outline. This coin was found with some others with personal initials in a 5,000 piece coin bag purchased from a coin show.", "Engineering,_Manufacturing": 0.9436061978, "qwen": "Yes"}
{"id": "535476", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=535476", "title": "Crash incompatibility", "text": "Crash incompatibility, crash compatibility, vehicle incompatibility, and vehicle compatibility are terms in the automobile crash testing industry. They refer to the tendency of some vehicles to inflict more damage on another vehicle (the \"crash partner vehicle\") in two-car crashes. Vehicle \"incompatibility\" is said to lead to more dangerous, fatal crashes, while \"compatibility\" can prevent injury in otherwise comparable crashes.\nThe most obvious source of crash incompatibility is mass; a high-mass vehicle such as a large MPV or SUV will tend to cause much more serious damage in a crash with a lighter vehicle such as a typical sedan or compact car. In particular, research by Michael Anderson and Maximilian Auffhammer suggests that \"controlling for own-vehicle weight, \nbeing hit by a vehicle that is 1,000 pounds heavier generates a 40-50% increase in fatality \nrisk.\" Incompatibility may also result from the specific shape, stiffness, or other design aspects of the impacting vehicles. For example, some SUVs and pickup trucks ride higher than cars and lack crumple zones to absorb impact energy. Another source of incompatibility is that heavier vehicles are required to have stronger front ends because of today's test requirements like the NCAP test.\nThe National Highway Traffic Safety Administration has done studies of the \"aggressiveness\" of vehicle designs. The term \"aggressiveness\" is used to denote the average injury risk a vehicle imposes on occupants of other vehicles during collisions. A 2003 NHTSA study estimated that in vehicle to vehicle crashes, the design of minivans was 1.16 times as aggressive as cars, pickups were 1.39 times more aggressive, and SUVs were 1.71 times more aggressive than cars. When weight was included in the analysis, light trucks (including SUVs) were estimated to be 3.3 times more aggressive than cars in head-on crashes and perhaps more so in side impact crashes.\nThese studies have been controversial as they affect public perception and policy decisions on CAFE standards and light truck safety test standards as they exist today. NHTSA does not define a car or a light truck based on weight (e.g., the Chrysler PT Cruiser is classified as a light truck whereas a Lexus LS 600h L, a vehicle that weighs 66% more per published specifications, is classified as a car). So while there have been no proposals to eliminate light trucks (which includes minivans, SUVs and pickups), doing so would not eliminate incompatibility because there would still be lighter vehicles crashing into heavier vehicles.\nThere has been extensive research and testing done by NHTSA, other governments, research organizations as well as automobile manufacturers to find solutions that improve safety in the small cars when colliding with larger vehicles. In the United States, a group of experts proposed major steps to improve compatibility and these have been accepted as a voluntary regulation by American automotive manufacturers as well as by most other companies selling vehicles in the U.S. The Canadian government has also accepted these recommendations. The recommendations require all manufacturers to either (a) lower the height of the primary structure (also called frame rail) of all SUV and pickup trucks so that they overlap the primary structure of the cars; or (b) add another structure (called Secondary Energy Absorbing Structure) to the SUVs and pickup truck that cannot meet the first option. Latest studies have shown that these have improved the safety in cars when struck by SUVs. However, no such benefit has been observed in pickup truck to car crashes. It is unclear whether or not certain aftermarket modifications are taken into account, such as \"lift kits\" which raise the frame or suspension of a vehicle for increased ground clearance. Such modifications would likely greatly reduce the effectiveness of modern auto-safety advances due to causing the rigid parts of a pickup or SUV to strike the weaker parts of lower vehicles, rather than the reinforced regions in an accident. State laws regarding the use of such modifications vary widely, and many have laws that aren't enforced. As of now, there are no Federal laws regarding the bumper height of trucks and SUV's.\nAlthough much of the crash incompatibility debate in recent years has centered on SUVs, the concept has been around far longer. When subcompact cars were introduced in the 1970s, there was a fear that incompatibilities of mass and design could lead to more serious injuries for drivers of these smaller, lighter vehicles. Crash incompatibility remains an area of active study.", "Engineering,_Manufacturing": 0.9830461144, "qwen": "Yes"}
{"id": "17421410", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=17421410", "title": "ALLDATA", "text": "ALLDATA LLC is an online source for automotive original equipment manufacturer (OEM) information. ALLDATA provides vehicle manufacturers' diagnostic and repair information.\nALLDATA was founded in 1986 to meet market demand for OE repair information. As computer technology took hold, ALLDATA began compiling the largest single source of OEM information available and converted it into a digital format. ALLDATA is known for online OEM information, used by over 300,000 professional technicians worldwide. The company expanded its product line to include collision information, business tools and support services for the global automotive industry.\nIn 1996, ALLDATA was purchased by AutoZone.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "39357175", "revid": "8665131", "url": "https://en.wikipedia.org/wiki?curid=39357175", "title": "Željeznički prevoz Crne Gore", "text": "Željeznički prevoz Crne Gore (ŽPCG) (Cyrillic: Жељезнички превоз Црне Горе; English: Railway transport of Montenegro) is a joint-stock company that handles passenger transport within Montenegro, as well as operation of the Montenegrin rolling stock.\nRolling stock.\nRolling stock of Railway transport of Montenegro consists of 39 locomotives and 5 EMUs:\nPassenger cars.\nRailway transport of Montenegro also has following inventory of passenger cars:\nFreight cars.\nFreight cars in inventory are as follows:", "Engineering,_Manufacturing": 1.0000077486, "qwen": "Yes"}
{"id": "4373936", "revid": "1164672905", "url": "https://en.wikipedia.org/wiki?curid=4373936", "title": "Heat deflection temperature", "text": "The heat deflection temperature or heat distortion temperature (HDT, HDTUL, or DTUL) is the temperature at which a polymer or plastic sample deforms under a specified load. This property of a given plastic material is applied in many aspects of product design, engineering and manufacture of products using thermoplastic components.\nDetermination.\nThe heat distortion temperature is determined by the following test procedure outlined in ASTM D648. The test specimen is loaded in three-point bending in the edgewise direction. The outer fiber stress used for testing is either 0.455 MPa or 1.82 MPa, and the temperature is increased at 2 °C/min until the specimen deflects 0.25 mm. This is similar to the test procedure defined in the ISO 75 standard.\nLimitations that are associated with the determination of the HDT is that the sample is not thermally isotropic and, in thick samples in particular, will contain a temperature gradient. The HDT of a particular material can also be very sensitive to stress experienced by the component which is dependent on the component’s dimensions. The selected deflection of 0.25 mm (which is 0.2% additional strain) is selected arbitrarily and has no particular physical significance.\nApplication in injection molding.\nAn injection molded plastic part is considered \"safe\" to remove from its mold once it is near or below the HDT. This means that part deformation will be held within acceptable limits after removal. The molding of plastics by necessity occurs at high temperatures (routinely 200 °C or higher) due to the low viscosity of plastics in fluid form (this issue can be addressed to some extent by the addition of plasticizers to the melt, which is a secondary function of a plasticizer). Once plastic is in the mold, it must be cooled to a temperature to which little or no dimensional change will occur after removal. In general, plastics do not conduct heat well and so will take quite a while to cool to room temperature. One way to mitigate this is to use a cold mold (thereby increasing heat loss from the part). Even so, the cooling of the part to room temperature can limit the mass production of parts.\nChoosing a resin with a higher heat deflection temperature (and therefore closer to melting temperature) can allow manufacturers to achieve a much faster molding process than they would otherwise while maintaining dimensional changes within certain limits.", "Engineering,_Manufacturing": 0.9999235868, "qwen": "Yes"}
{"id": "4376638", "revid": "38647647", "url": "https://en.wikipedia.org/wiki?curid=4376638", "title": "Design studio", "text": "A design studio or drawing office is a workplace for designers and artisans engaged in conceiving, designing and developing new products or objects. Facilities in a design studio include clothes, furniture art equipment best suited for design work and extending to work benches, small machines, computer equipment, paint shops and large presentation boards.\nSize.\nThe size and conveniences also depends upon the type of the studio. Freelance designers engaged in product design often have a small set-up of their own, the smallest being within private residences. The ambiance of a design studio is often noted for its informality. The number of designers working in a typical design studio may vary widely, from a single individual to up to 1000 members. In such large studios, apart from designers, the staff may also consist of other technicians and artisans engaged in prototyping and engineering detailing, in addition to administrative staff and designers. They’re composed of flexible work spaces where design thinking thrives\nOwnership.\nThe smallest studios are operated by individuals, while the medium to bigger ones may be owned and operated by manufacturers involved in consumer goods or by design firms engaged in design services catering to different firms and industries. Such independent design studios may also function as design studios as well as design firms.\nTypes.\nAutomotive design studios.\nAutomotive design studios are usually large, where space is required for multiple cars under development, in addition to clay modeling surface tables, large scanners and clay milling machines. Such studios also have a presentation area to accommodate at least 20 to 30 people for presentations and design briefings with clients. Automobile manufacturer studios are often treated as a separate entity and housed within a compound. Most of these design studios are often located in a different part of the city or country and are isolated from the manufacturing and engineering environment. Such studios are often high security areas, where even internal access to most areas is severely restricted.\nOKB.\nOKB is a transliteration of the Russian initials of \"\" – , meaning 'experimental design bureau'. During the Soviet era, OKBs were closed institutions working on design and prototyping of advanced technology, usually for military applications.", "Engineering,_Manufacturing": 0.999555409, "qwen": "Yes"}
{"id": "45498497", "revid": "253891", "url": "https://en.wikipedia.org/wiki?curid=45498497", "title": "Ken Brock Manufacturing", "text": "Ken Brock Manufacturing, Inc. was an American aircraft manufacturer founded by Ken Brock in the 1960s and based in Stanton, California. The company specialized in the design and manufacture of autogyros in the form of kits for amateur construction, including under the US FAR 103 Ultralight Vehicles rules.\nKen Brock Manufacturing produced a number of aircraft designs including the Brock KB-1, Brock KB-2 and Brock KB-3 autogyros, plus the Ken Hovey-engineered Brock Avion ultralight aircraft. The company was also noted for the high-quality aircraft parts that it produced for other designer's aircraft, especially the Rutan Long-EZ and the Cozy Mark IV.\nThe company occupied a plant that included lathes, milling machines, drill presses, tap and die making, equipment for heat treating metal, plating and welding.\nA subsidiary was Santa Ana Metal Stamping, which Brock set up to produce stamped metal parts using numerical control machinery.\nThe company closed for business at the end of 2005 after Brock's death on 19 October 2001 while landing a Thorp T-18. After his death, Brock's widow, Marie Brock, who survived the 2001 accident, attempted to sell the business and parts on hand. Aircraft Spruce & Specialty Co purchased the Cozy Mark IV parts inventory, jigs, tooling and drawings.", "Engineering,_Manufacturing": 0.999327302, "qwen": "Yes"}
{"id": "45522513", "revid": "5042921", "url": "https://en.wikipedia.org/wiki?curid=45522513", "title": "Electro sinter forging", "text": "Electro sinter forging (ESF) is an industrial single electromagnetic pulse sintering technique to rapidly produce a wide range of small components in metals, alloys, intermetallics, semiconductors, and composites. ESF was invented by Alessandro Fais, an Italian metallurgical engineer and scientist.\nESF is obtained by inserting loose, binder-less powders into the automatic dosing system, or manually inserted in the mold. The automatic procedure applies a pre-pressure onto the powders to ensure electrical contact; hence, it superimposes an intense electromagnetic pulse with a mechanical pulse. The two pulses last 30 to 100 ms. After a brief holding time, the sintered component is extracted by the lower plunger and pushed out by the extractor to leave room for the next sintering. Each sintering round lasts less than one second, and is carried out entirely in air (even with pyrophoric materials).", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "59449468", "revid": "15420072", "url": "https://en.wikipedia.org/wiki?curid=59449468", "title": "Toyota Auto Body", "text": "Toyota Auto Body  is a manufacturing subsidiary of the Toyota group based in Japan. It is headquartered in Kariya, Aichi and was established in 1945. The company has plants in the Mie and Aichi prefectures and other facilities around Japan and abroad.\nThe company was formed through a corporate spin-off from Toyota. In its early years, it produced auto bodies. In the late 1950s and early 1960s, it centred on truck production, before slowly switching focus to light vehicles (mostly vans) from the late 1960s onwards. In the 2000s, it absorbed the vehicle manufacturing operations of sister companies Araco and Gifu Auto Body.\nAs part of Toyota, Toyota Auto Body develops and produces a range of minivans, SUVs, light commercial vehicles and auto parts.\nHistory.\nToyota Auto Body was established on 31 August 1945 as a corporate spin-off of Toyota Motor Industry's Kariya plant with the name . At first, it produced auto bodies for Toyota. In 1951, the company became the first Japanese manufacturer in producing a truck body made completely of steel. In 1953, the company adopted its present name. In January 1957, it opened an assembly facility in Kariya for mass-producing trucks. In November 1959, it created a vehicle conversion subsidiary, \nKariya Painting (later renamed Tokai Utility Motor).\nIn the early 1960s, Toyota gave clear functions to some of its then (subcontracting) companies: Toyota Auto Body was centred on producing trucks; Kanto Auto Works passenger vans and pickups; Arakawa Auto Body Land Cruisers and special vehicles. In 1960, Toyota Auto Body produced 74,000 trucks (including large trucks, the Stout, the ToyoAce), an 87% of Toyota's overall truck production and a 48% of its total vehicle production. In 1964, truck production from Toyota Auto Body (large trucks, the Stout, the ToyoAce, the Dyna) rose to 116,000 trucks, comprising 90% of Toyota's truck production and 27% of all vehicles.\nIn January 1964, Toyota Auto Body opened a second assembly facility in Kariya, the Fujimatsu plant, which produced the first Japanese hard-top car during the 1960s, the Corona Hard-top. The company also became the first in assembling mass-produced passenger cars. The production percentage of passenger cars and other light vehicles would increase for the company during the following years. In the late 1960s, Toyota Auto Body led the development of a small van with a design, similar to European ones at the time, but, according to former Toyota senior employee Akira Kawahara, something yet unseen in the Japanese industry. In 1967, Toyota Auto Body began producing the van, named as HiAce. It became the most produced model from the company with more than 6 million units . Toyota Auto Body would continue developing and producing design vans. In 1970, Toyota Auto Body production was 149,000 passenger cars and 142,000 commercial vehicles (trucks and buses), although the actual percentage declined to 17.6% of Toyota's total vehicle production.\nIn the 1970s, Toyota Auto Body was one of the first companies in using quality function deployment (QFD), paralleling the initial developments from Yoji Akao at Mitsubishi Heavy Industries. The rest of the Toyota group adopted the method in 1979. The improvements of Toyota Auto Body on QFD influenced Ford into adopting it.\nIn 1992, the company established Toyota Body Seiko, an auto parts subsidiary, and began investments to increase the production of vehicles, as the rest of its passenger car business was in decline. In December 1993, Toyota Auto Body opened the van-focused Inabe plant. By the mid-1990s, Toyota Auto Body ventured into the production of high-end passenger vans derived from the HiAce. In 1995, it started producing the Granvia, a HiAce-based semi-bonneted van made to comply with European safety regulations. From the Granvia the company developed the Alphard which was launched in 2002. In 2008, it introduced an Alphard twin vehicle, the Vellfire.\nIn May 2001, Toyota announced it would consolidate all production of Toyota-badged cars intended for the Japanese market into Toyota Auto Body by moving the assembly of the LiteAce/TownAce Noah and its successor (Noah) from Daihatsu. In 2004, Toyota Auto Body incorporated the auto body and vehicle production businesses from Araco. In 2005, the Kariya plant was repurposed for converting vehicles instead of producing trucks. In the fiscal year ended March 2007, Toyota Auto Body achieved its largest production volume, with about 745,000 vehicles produced during the period. In 2007, Gifu Auto Body became a wholly owned subsidiary of Toyota Auto Body.\nIn November 2018, Toyota announced it would transfer all van development to Toyota Auto Body. In 2019, Toyota Auto Body announced it would produce the first Lexus-badged passenger van at its Inabe plant, the Lexus LM, a badge engineered Alphard, the second Lexus product coming from the company after the Land Cruiser-based Lexus LX (the latter a legacy product from Araco).\nIn December 2022, Toyota Auto Body signed an agreement by which it plans to sell shares of Toyota Body Seiko to Toyota Boshoku, a minority shareholder, by October 2023, increasing the latter's ownership to a 66.4% controlling stake. After the transaction, Toyota Body Seiko would become a subsidiary of Toyota Boshoku instead of Toyota Auto Body and change its name to Toyota Boshoku Seiko. Toyota Boshoku may turn Toyota Boshoku Seiko into a wholly owned subsidiary at a later date.\nIn the early 2020s, the company opened specialty stores for customising and selling accessories of its produced vehicles. In January 2023, it pre-opened a Land Cruiser customisation and services store in Kariya, operated by Tokai Utility Motor, and called to be fully operational by mid-2023. In June 2023, it opened another for its commercial vehicle range in Fukagawa, Tokyo (within the Toyota Mobility Tokyo store), which is called .\nToyota Auto Body was a public company until late 2011, when Toyota made it a wholly owned subsidiary and delisted its shares.\nFacilities.\nVehicle assembly and management.\nToyota Auto Body assembly plants are Fujimatsu (Ichiriyama, Kariya, Aichi), Inabe (Inabe, Mie), Yoshiwara (Yoshiwara, Toyota, Aichi), Kariya (Showa, Kariya, Aichi). There is a development centre in Toyota, Aichi (Kotobuki New Development Centre). The head offices are in Kariya, Aichi. Additional offices are located in Tokyo and Osaka.\nThe Fujimatsu plant covers a 436,700 square metres (m2) area and was established in January 1964. The present Kariya plant, covering 99,100 m2, was established in 1957. Both plant produce vehicles, but Fujimatsu is mostly focused on minivans and Kariya on electric vehicles. , the plants had a combined workforce of 3,139 (281 of them working at the Kariya plant). The Inabe plant is the main minivan production hub of Toyota Auto Body. It covers 800,500 m2 and was established in December 1993. , it had 2,266 employees. The Yoshiwara plant produces body-on-frame vehicles. It covers 196,200 m2 and was established in 1962. , it had 2,337 employees. By the 1999 fiscal year, all Toyota Auto Body plants got the ISO 14001 certification. The company's plants use the Toyota Production System. \nToyota Auto Body's Gifu Auto Body headquarters and facilities are in Unuma Mitsuike, Kakamigahara, Gifu. Its facilities cover 163,000 m2. , the company had 2,565 employees. \nOther facilities.\n is Toyota Auto Body wholly owned research and development subsidiary. It is headquartered in Kirishima, Kagoshima and was established in 1990. Toyota Auto Body made design and development work for Toyota from the early 1960s, and, together with Toyota and sister companies, formed part of ATODE (All TOyota DEsign), a group formed in December 1960 aimed at securing a consistent styling for Toyota-badged vehicles. The Toyota Auto Body's design branch became an autonomous part of the company in 1978. The present Toyota Auto Body Research and Development subsidiary has a 5,719 m2 building and 403 employees.\nTokai Utility Motor has facilities in Anjō, Kariya, and Inabe. Toyota Body Seiko in Takahama, Toyohashi, Inabe, Kakamigahara, and two overseas plants (in China and Thailand).\nOverseas subsidiaries.\nToyota Auto Body has subsidiaries in Indonesia, Taiwan, Thailand, Malaysia, China and the United States.\nMost Toyota Auto Body's affiliates outside Japan are joint ventures. The Taoyuan-based Taiwanese affiliate is called Chun Shyang Shin Yeh (Industry)  and was established in 1997. It is a joint venture between Toyota Auto Body and Chun Yuan Steel, a Taiwanese steel manufacturer. The joint venture produces pressed parts, vehicle doors and suspension components for Toyota cars. Toyota Auto Body owns a 51% stake. In Thailand, Toyota Auto Body's first Thai operations began in February 1978, producing stamped parts for Hilux pickups. Toyota Auto Body Thailand officially started activities in 1979, as a stamped auto parts producer. In 1988, it formed a joint venture with Toyota Motor Thailand called Toyota (formerly Thai) Auto Works. The venture is focused on producing the HiAce. Toyota Auto Body owns a 63% stake. Both Thai ventures have plants in Samutprakan: the Samrong plant (Toyota Auto Body Thailand) and the Teparak plant (Toyota Auto Works). In 2004, Toyota Auto Body established a joint venture called Thai Auto Conversion aimed at producing specially equipped vehicles. \nToyota Auto Body also has various joint ventures in Indonesia. In 1995, it established, along with other Toyota subsidiaries, Sugity Creatives, an Indonesian joint venture headquartered in Cikarang Bekasi and aimed at producing resin components for cars. From late 2012 to 2016 it produced vehicles, including the Noah (rebadged as NAV1). Toyota Auto Body owns an 88.52% of the venture. Toyota Auto Body also has stakes in the joint ventures Toyota Auto Body-Tokai Extrusion and Resin Plating Technology, both producing auto parts. As for China, Toyota Auto Body has a 65%-owned Chinese joint venture, Tab Minth Mobility Equipment, to \"sell assistive components\".\nThe rest of the Toyota Auto Body's overseas affiliates are wholly owned subsidiaries. These are the Malaysian auto parts producer Toyota Auto Body Malaysia (established in 2005) and the American Auto Parts Manufacturing Mississippi (established in 2011).\nProducts.\n vehicles assembled by Toyota Auto Body include: the Alphard, the Vellfire, the Voxy, the Noah, the Land Cruiser, the HiAce, the RegiusAce, the GranAce, the Coaster, the electric vehicle COMS, the \nLexus LX and LM.\nAbsorbed operations.\nAraco.\n was one of the first manufacturing subsidiaries of Toyota. It was established in 1946 (incorporated July 1947) at Nagoya by a former Toyota Industries sheet metal worker named Gihee Arakawa as . The company firstly made sheet metal work for Toyota, soon adding vehicle interior parts (including seats) and auto bodies. In 1953, it started assembling the Toyota BJ, and later the successive Land Cruisers. The Arakawa-assembled Land Cruiser was the main export product from Toyota in the late 1950s and early 1960s (28% of all vehicle exports in the period 1956–1964). In 1960, it entered into production the RK160B (Coaster). The company opened two new plants around Toyota City during the 1960s: Kotobuki (1960) and Yoshiwara (1962). It was renamed as in 1961, before adopting the \"Araco\" name in 1988. In 1995, the company began assembling Lexus vehicles. In 2004, Araco activities were split and the auto body and vehicle production operations became part of Toyota Auto Body. The vehicle interior business was merged into Toyota Boshoku.\nA different Toyota subsidiary established in 1974 as was renamed as \"Kyoei Araco\" in 2004 and as \"Araco\" in 2015. This Araco specialises on seats for Lexus vehicles.\nGifu Auto Body.\n is a Gifu-based vehicle manufacturer. It was established in 1940 as a truck body manufacturer. In 1959, after receiving a big order of military vehicles from Toyota, it associated itself with the latter, producing bodies for light trucks such as the Dyna and the Stout. In the 1960s, Gifu Auto Body hand-built the Land Cruiser FJ45V, a long wheelbase variant of the third-generation Land Cruiser. Up until 1967, the company's production was focused on the Land Cruiser model and light trucks. That year, Toyota consolidated all Land Cruiser assembly in Japan into Arakawa Auto Body Industries. From 1967 onwards, the main focus of Gifu Auto Body became the production of light trucks and the HiAce until Toyota transferred truck production to Hino Motors in 1998. In January 1996, Toyota launched a civilian version of the BXD10 military vehicle called BXD20 (Mega Cruiser), and it was assembled by Gifu Auto Body. Production ended in August 2001.\nBy 2007, Gifu Auto Body was producing the HiAce and auto parts (pressed parts and truck seats). That year, it became a wholly owned subsidiary of Toyota Auto Body through stock swap. In July 2015, Gifu Auto Body transferred its auto parts business to Toyota Body Seiko in order to focus on commercial vehicle assembly. In December 2016, Toyota Auto Body moved production of the Coaster from its Yoshiwara plant to Gifu Auto Body.\nSports.\nAn Araco team entered Land Cruisers into the Rally Dakar from 1995 onwards. In 2005, the team was renamed as . , it achieved ten consecutive victories in the diesel production car class. The company entered a HiAce into the 2023 Toyota Gazoo Racing Rally Challenge. The HiAce rally version was built on a GDH201V chassis modified by Cast (a HiAce tuning division of the Sanko Works company) and it is run by Toyota Auto Body's own team, . Cast had already entered a couple of HiAces into the 2021 All-Japan Rally Championship.\nToyota Auto Body has two company teams participating in Japanese national sports championships: the volleyball team Toyota Auto Body Queenseis and the handball team Toyota Auto Body Brave Kings.\n, Gifu Auto Body is sponsor of FC Gifu.", "Engineering,_Manufacturing": 0.998876214, "qwen": "Yes"}
{"id": "4264590", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=4264590", "title": "Labour Inspection Convention, 1947", "text": "Labour Inspection Convention, 1947 is an International Labour Organization Convention.\nIt was established in 1947 with the preamble stating:\nHaving decided upon the adoption of certain proposals with regard to the organisation of labour inspection in industry and commerce...\nRatifications.\nAs of 2021, 148 of the 186 ILO states had ratified the convention.", "Engineering,_Manufacturing": 0.9999815226, "qwen": "Yes"}
{"id": "25877264", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=25877264", "title": "W.W. (automobile)", "text": "W.W. (Winter), was an early British car made by Winter and Company of Wandsworth, London. They made two models between 1913 and 1914.\nThe first car, the W.W. of 1913 was a light car powered by an 8 hp V-twin engine bought in from the Precision company. This drove the rear wheels through a gear box by Chater-Lea and shaft drive to a worm gear final drive on the rear axle.\nFor 1914 production changed to a cyclecar. This was sold as a Winter and had a Blumfield engine and friction drive with belt to the rear axle.\nThe number made is not known.", "Engineering,_Manufacturing": 0.9997614026, "qwen": "Yes"}
{"id": "1249227", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1249227", "title": "Surface micromachining", "text": "Surface micromachining builds microstructures by deposition and etching structural layers over a substrate. This is different from Bulk micromachining, in which a silicon substrate wafer is selectively etched to produce structures.\nLayers.\nGenerally, polysilicon is used as one of the substrate layers while silicon dioxide is used as a \"sacrificial layer.\" The sacrificial layer is removed or etched out to create any necessary void in the thickness direction. Added layers tend to vary in size from 2-5 micrometres. The main advantage of this machining process is the ability to build electronic and mechanical components (functions) on the same substrate. Surface micro-machined components are smaller compared to their bulk micro-machined counterparts.\nAs the structures are built on top of the substrate and not inside it, the substrate's properties are not as important as in bulk micro-machining. Expensive silicon wafers can be replaced by cheaper substrates, such as glass or plastic. The size of the substrates may be larger than a silicon wafer, and surface micro-machining is used to produce thin-film transistors on large area glass substrates for flat panel displays. This technology can also be used for the manufacture of thin film solar cells, which can be deposited on glass, polyethylene terepthalate substrates or other non-rigid materials.\nFabrication process.\nMicro-machining starts with a silicon wafer or other substrate upon which new layers are grown. These layers are selectively etched by photo-lithography; either a wet etch involving an acid, or a dry etch involving an ionized gas (or plasma). Dry etching can combine chemical etching with physical etching or ion bombardment. Surface micro-machining involves as many layers as are needed with a different mask (producing a different pattern) on each layer. Modern integrated circuit fabrication uses this technique and can use as many as 100 layers. Micro-machining is a younger technology and usually uses no more than 5 or 6 layers. Surface micro-machining uses developed technology (although sometimes not enough for demanding applications) which is easily repeatable for volume production.\nSacrificial layers.\nA sacrificial layer is used to build complicated components, such as movable parts. For example, a suspended cantilever can be built by depositing and structuring a sacrificial layer, which is then selectively removed at the locations where the future beams must be attached to the substrate (i.e. the anchor points). A structural layer is then deposited on top of the polymer and structured to define the beams. Finally, the sacrificial layer is removed to release the beams, using a selective etch process that does not damage the structural layer.\nMany combinations of structural and sacrificial layers are possible. The combination chosen depends on the process. For example, it is important for the structural layer not to be damaged by the process used to remove the sacrificial layer.\nExamples.\nSurface Micro-machining can be seen in action in the following MEMS (Microelectromechanical) products:", "Engineering,_Manufacturing": 0.9999774694, "qwen": "Yes"}
{"id": "1249261", "revid": "31926656", "url": "https://en.wikipedia.org/wiki?curid=1249261", "title": "Bulk micromachining", "text": "Bulk micromachining is a process used to produce micromachinery or microelectromechanical systems (MEMS).\nUnlike surface micromachining, which uses a succession of thin film deposition and selective etching, bulk micromachining defines structures by selectively etching inside a substrate. Whereas surface micromachining creates structures \"on top\" of a substrate, bulk micromachining produces structures \"inside\" a substrate.\nUsually, silicon wafers are used as substrates for bulk micromachining, as they can be anisotropically wet etched, forming highly regular structures. Wet etching typically uses alkaline liquid solvents, such as potassium hydroxide (KOH) or tetramethylammonium hydroxide (TMAH) to dissolve silicon which has been left exposed by the photolithography masking step. These alkali solvents dissolve the silicon in a highly anisotropic way, with some crystallographic orientations dissolving up to 1000 times faster than others. Such an approach is often used with very specific crystallographic orientations in the raw silicon to produce V-shaped grooves. The surface of these grooves can be atomically smooth if the etch is carried out correctly, and the dimensions and angles can be precisely defined. Pressure sensors are usually created by bulk micromachining technique.\nBulk micromachining starts with a silicon wafer or other substrates which is selectively etched, using photolithography to transfer a pattern from a mask to the surface. Like surface micromachining, bulk micromachining can be performed with wet or dry etches, although the most common etch in silicon is the anisotropic wet etch. This etch takes advantage of the fact that silicon has a crystal structure, which means its atoms are all arranged periodically in lines and planes. Certain planes have weaker bonds and are more susceptible to etching. The etch results in pits that have angled walls, with the angle being a function of the crystal orientation of the substrate. This type of etching is inexpensive and is generally used in early, low-budget research.\nExternal links.\n ", "Engineering,_Manufacturing": 1.0000078678, "qwen": "Yes"}
{"id": "897787", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=897787", "title": "Cartesian coordinate robot", "text": "A Cartesian coordinate robot (also called linear robot) is an industrial robot whose three principal axes of control are linear (i.e. they move in a straight line rather than rotate) and are at right angles to each other. The three sliding joints correspond to moving the wrist up-down, in-out, back-forth. Among other advantages, this mechanical arrangement simplifies the robot control arm solution. It has high reliability and precision when operating in three-dimensional space. As a robot coordinate system, it is also effective for horizontal travel and for stacking bins.\nConfigurations.\nRobots have mechanisms consisting of rigid links connected together by joints with either linear (prismatic \"P\") or rotary (revolute \"R\") motion, or combinations of the two.  Active prismatic \"P\" and active revolute \"R\" joints are driven by motors under programmable control to manipulate objects to perform complex automated tasks. The linear motion of active prismatic \"P\" joints may be driven by rotary motors through gears or pulleys. Cartesian coordinate robots are controlled by mutually active prismatic \"P\" joints that are aligned with the \"X, Y, Z\" axes of a Cartesian coordinate system.  Although not strictly ‘robots’, other types of manipulators, such as computer numerically controlled (CNC) machines, 3D printers or pen plotters, also have the same mechanical arrangement of mutually perpendicular active prismatic \"P\" joints.\nJoint topology.\nA single chain of links and joints connects a moving object to a base of serial manipulators. Multiple chains (limbs) connect the moving object to the base of parallel manipulators.  Most Cartesian coordinate robots are fully serial or a combination of serial and parallel connected linkages.  However, there are some Cartesian coordinate robots that are fully parallel-connected.\nDegrees of freedom.\nSince they are driven by linear active prismatic \"P\" joints, Cartesian coordinate robots typically manipulate objects with only linear translation \"T\" degrees of freedom.  However, some Cartesian coordinate robots also have rotational \"R\" degrees of freedom.\nConstruction.\nEach axis of a Cartesian coordinate robot typically is a linear stage consisting of a linear actuator geometrically parallel with linear bearings. The linear actuator is typically between two linear bearings spaced apart from each other to support moment loads.  Two perpendicular linear stages stacked on top of each other form an XY table.  Examples of XY tables include the XY axes of milling machines or precision positioning stages. At least one of the linear stages of cantilevered Cartesian coordinate robots is supported at only one end. Cantilevered construction provides accessibility to parts for pick-and-place applications such as laboratory automation for example. Cartesian coordinate robots with the horizontal member supported at both ends are sometimes called gantry robots; mechanically, they resemble gantry cranes, although the latter are not generally robots. Gantry robots are often quite large and may support heavy loads.\nApplications.\nPopular applications for Cartesian coordinate robots are computer numerical control machines (CNC machine) and 3D printing. The simplest application is used in milling machines and plotters where a tool such as a router or pen translates across an \"X-Y\" plane and is raised and lowered onto a surface to create a precise design.\nPick and place machines are another application for Cartesian coordinate robots.  For example, overhead gantry Cartesian robots are applied for continuous parts loading and unloading on CNC lathes production lines, performing 3-axis \"(X, Y, Z)\" pick and place operations of heavy loads with high speed performance and high positioning accuracy.  In general, overhead gantry Cartesian robots are suitable for many automation systems.", "Engineering,_Manufacturing": 0.9999468327, "qwen": "Yes"}
{"id": "900867", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=900867", "title": "Drilling", "text": "Drilling is a cutting process where a drill bit is spun to cut a hole of circular cross-section in solid materials. The drill bit is usually a rotary cutting tool, often multi-point. The bit is pressed against the work-piece and rotated at rates from hundreds to thousands of revolutions per minute. This forces the cutting edge against the work-piece, cutting off chips (swarf) from the hole as it is drilled.\nIn rock drilling, the hole is usually not made through a circular cutting motion, though the bit is usually rotated. Instead, the hole is usually made by hammering a drill bit into the hole with quickly repeated short movements. The hammering action can be performed from outside the hole (top-hammer drill) or within the hole (down-the-hole drill, DTH). Drills used for horizontal drilling are called drifter drills.\nIn rare cases, specially-shaped bits are used to cut holes of non-circular cross-section; a square cross-section is possible.\nProcess.\nDrilled holes are characterized by their sharp edge on the entrance side and the presence of burrs on the exit side (unless they have been removed). Also, the inside of the hole usually has helical feed marks.\nDrilling may affect the mechanical properties of the workpiece by creating low residual stresses around the hole opening and a very thin layer of highly stressed and disturbed material on the newly formed surface. This causes the workpiece to become more susceptible to corrosion and crack propagation at the stressed surface.\nA finish operation may be done to avoid these detrimental conditions.\nFor fluted drill bits, any chips are removed via the flutes. Chips may form long spirals or small flakes, depending on the material, and process parameters. The type of chips formed can be an indicator of the machinability of the material, with long chips suggesting good material machinability.\nWhen possible drilled holes should be located perpendicular to the workpiece surface. This minimizes the drill bit's tendency to \"walk\", that is, to be deflected from the intended center-line of the bore, causing the hole to be misplaced. The higher the length-to-diameter ratio of the drill bit, the greater the tendency to walk. The tendency to walk is also preempted in various other ways, which include:\nSurface finish produced by drilling may range from 32 to 500 microinches. Finish cuts will generate surfaces near 32 microinches, and roughing will be near 500 microinches.\nCutting fluid is commonly used to cool the drill bit, increase tool life, increase speeds and feeds, increase the surface finish, and aid in ejecting chips. Application of these fluids is usually done by flooding the workpiece with coolant and lubricant or by applying a spray mist.\nIn deciding which drill(s) to use it is important to consider the task at hand and evaluate which drill would best accomplish the task. There are a variety of drill styles that each serve a different purpose. The subland drill is capable of drilling more than one diameter. The spade drill is used to drill larger hole sizes. The indexable drill is useful in managing chips.\nSpot drilling.\nThe purpose of spot drilling is to drill a hole that will act as a guide for drilling the final hole. The hole is only drilled part way into the workpiece because it is only used to guide the beginning of the next drilling process.\nCentre drilling.\nCentre drill is a two-fluted tool consisting of a twist drill with a 60° countersink; used to drill countersink center holes in a workpiece to be mounted between centers for turning or grinding.\nDeep hole drilling.\nDeep hole drilling is defined as drilling a hole of depth greater than ten times the diameter of the hole. These types of holes require special equipment to maintain the straightness and tolerances. Other considerations are roundness and surface finish.\nDeep hole drilling is generally achievable with a few tooling methods, usually gun drilling or BTA drilling. These are differentiated due to the coolant entry method (internal or external) and chip removal method (internal or external). Using methods such as a rotating tool and counter-rotating workpiece are common techniques to achieve required straightness tolerances. Secondary tooling methods include trepanning, skiving and burnishing, pull boring, or bottle boring. Finally, a new kind of drilling technology is available to face this issue: vibration drilling. This technology breaks up the chips by a small controlled axial vibration of the drill. The small chips are easily removed by the flutes of the drill.\nA high tech monitoring system is used to control force, torque, vibrations, and acoustic emission. Vibration is considered a major defect in deep hole drilling which can often cause the drill to break. A special coolant is usually used to aid in this type of drilling.\nGun drilling.\nGun drilling was originally developed to drill out gun barrels and is used commonly for drilling smaller diameter deep holes. The depth-to-diameter ratio can be even greater than 300:1. The key feature of gun drilling is that the bits are self-centering; this is what allows for such deep accurate holes. The bits use a rotary motion similar to a twist drill; however, the bits are designed with bearing pads that slide along the surface of the hole keeping the drill bit on center. Gun drilling is usually done at high speeds and low feed rates.\nTrepanning.\nTrepanning is commonly used for creating larger diameter holes (up to ) where a standard drill bit is not feasible or economical. Trepanning removes the desired diameter by cutting out a solid disk similar to the workings of a drafting compass. Trepanning is performed on flat products such as sheet metal, granite (curling stone), plates, or structural members like I-beams. Trepanning can also be useful to make grooves for inserting seals, such as O-rings.\nMicrodrilling.\nMicrodrilling refers to the drilling of holes less than . Drilling of holes at this small diameter presents greater problems since coolant fed drills cannot be used and high spindle speeds are required. High spindle speeds that exceed 10,000 RPM also require the use of balanced tool holders.\nVibration drilling.\nThe first studies into vibration drilling began in the 1950s (Pr. V.N. Poduraev, Moscow Bauman University). The main principle consists in generating axial vibrations or oscillations in addition to the feed movement of the drill so that the chips break up and are then easily removed from the cutting zone.\nThere are two main technologies of vibration drilling: self-maintained vibration systems and forced vibration systems. Most vibration drilling technologies are still at a research stage. In the case of self-maintained vibration drilling, the eigenfrequency of the tool is used in order to make it naturally vibrate while cutting; vibrations are self-maintained by a mass-spring system included in the tool holder. Other works use a piezoelectric system to generate and control the vibrations. These systems allow high vibration frequencies (up to 2 kHz) for small magnitude (about a few micrometers); they are particularly suitable for drilling small holes. Finally, vibrations can be generated by mechanical systems: the frequency is given by the combination of the rotation speed and the number of oscillation per rotation (a few oscillations per rotation), with magnitude about 0.1 mm.\nThis last technology is a fully industrial one (example: SineHoling® technology of MITIS). Vibration drilling is a preferred solution in situations like deep hole drilling, multi-material stack drilling (aeronautics) and dry drilling (without lubrication). Generally, it provides improved reliability and greater control of the drilling operation.\nCircle interpolating.\n\"Circle interpolating\", also known as \"orbital drilling\", is a process for creating holes using machine cutters.\nOrbital drilling is based on rotating a cutting tool around its own axis and simultaneously about a centre axis which is off-set from the axis of the cutting tool. The cutting tool can then be moved simultaneously in an axial direction to drill or machine a hole – and/or combined with an arbitrary sidewards motion to machine an opening or cavity.\nBy adjusting the offset, a cutting tool of a specific diameter can be used to drill holes of different diameters as illustrated. This implies that the cutting tool inventory can be substantially reduced.\nThe term orbital drilling comes from that the cutting tool “orbits” around the hole center. The mechanically forced, dynamic offset in orbital drilling has several advantages compared to conventional drilling that drastically increases the hole precision. The lower thrust force results in a burr-less hole when drilling in metals. When drilling in composite materials the problem with delamination is eliminated.\nMaterial.\nDrilling in metal.\nUnder normal usage, swarf is carried up and away from the tip of the drill bit by the fluting of the drill bit. The cutting edges produce more chips which continue the movement of the chips outwards from the hole. This is successful until the chips pack too tightly, either because of deeper than normal holes or insufficient \"backing off\" (removing the drill slightly or totally from the hole while drilling). Cutting fluid is sometimes used to ease this problem and to prolong the tool's life by cooling and lubricating the tip and chip flow. Coolant may be introduced via holes through the drill shank, which is common when using a gun drill. When cutting aluminum in particular, cutting fluid helps ensure a smooth and accurate hole while preventing the metal from grabbing the drill bit in the process of drilling the hole. When cutting brass, and other soft metals that can grab the drill bit and causes \"chatter\", a face of approx. 1-2 millimeters can be ground on the cutting edge to create an obtuse angle of 91 to 93 degrees. This prevents \"chatter\" during which the drill tears rather than cuts the metal. However, with that shape of bit cutting edge, the drill is pushing the metal away, rather than grabbing the metal. This creates high friction and very hot swarf.\nFor heavy feeds and comparatively deep holes oil-hole drills are used in the drill bit, with a lubricant pumped to the drill head through a small hole in the bit and flowing out along the fluting. A conventional drill press arrangement can be used in oil-hole drilling, but it is more commonly seen in automatic drilling machinery in which it is the workpiece that rotates rather than the drill bit.\nIn computer numerical control (CNC) machine tools a process called \"\", or \"interrupted cut drilling\", is used to keep swarf from detrimentally building up when drilling deep holes (approximately when the depth of the hole is three times greater than the drill diameter). Peck drilling involves plunging the drill part way through the workpiece, no more than five times the diameter of the drill, and then retracting it to the surface. This is repeated until the hole is finished. A modified form of this process, called \"high speed peck drilling\" or \"chip breaking\", only retracts the drill slightly. This process is faster, but is only used in moderately long holes, otherwise it will overheat the drill bit. It is also used when drilling stringy material to break the chips.\nWhen it is not possible to bring the material to the СNС machine, a Magnetic Base Drilling Machine may be used. The base allows drilling in a horizontal position and even on a ceiling. Usually, for these machines, it is better to use cutters because they can drill much faster with less speed. Cutter sizes vary from 12mm to 200mm DIA and from 30mm to 200mm DOC(depth of cut). These machines are widely used in construction, fabrication, marine, and oil & gas industries. In the oil and gas industry, pneumatic magnetic drilling machines are used to avoid sparks, as well as special tube magnetic drilling machines that can be fixed on pipes of different sizes, even inside. Heavy-duty plate drilling machines provide high-quality solutions in the manufacturing of steel construction, bridge construction, shipyards, and various fields of the construction sector.\nDrilling in wood.\nWood being softer than most metals, drilling in wood is considerably easier and faster than drilling in metal. Cutting fluids are not used or needed. The main issue in drilling wood is ensuring clean entry and exit holes and preventing burning. Avoiding burning is a question of using sharp bits and the appropriate cutting speed. Drill bits can tear out chips of wood around the top and bottom of the hole and this is undesirable in fine woodworking applications.\nThe ubiquitous twist drill bits used in metalworking also work well in wood, but they tend to chip wood out at the entry and exit of the hole. In some cases, as in holes for rough carpentry, the quality of the hole does not matter, and a number of bits for fast cutting in wood exist, including spade bits and self-feeding auger bits. Many types of specialised drill bits for boring clean holes in wood have been developed, including brad-point bits, Forstner bits and hole saws. Chipping on exit can be minimized by using a piece of wood as backing behind the work piece, and the same technique is sometimes used to keep the hole entry neat.\nHoles are easier to start in wood as the drill bit can be accurately positioned by pushing it into the wood and creating a dimple. The bit will thus have little tendency to wander.\nOthers.\nSome materials like plastics as well as other non-metals and some metals have a tendency to heat up enough to expand making the hole smaller than desired.\nRelated processes.\nThe following are some related processes that often accompany drilling:", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "12961208", "revid": "1069822031", "url": "https://en.wikipedia.org/wiki?curid=12961208", "title": "Single-pass bore finishing", "text": "Single-pass bore finishing is a machining process similar to honing to finish a bore, except the tool only takes a single pass. The process was originally developed to improve bore quality in cast iron workpieces.\nProcess.\nThis process uses multiple diamond-plated, barrel-shaped tools to finish a bore. The tool has a single layer of diamonds bonded to the tool, with about half of each diamond exposed. These special tools are made to a specific diameter and are only meant to open up the hole to that size.\nThe tools are usually mounted in a dedicated bore finishing machine, however they can also be mounted in a milling machine. In either case the tool, workpiece, or both are rotated and the tool is plunged into the bore and removed. The part is then transferred to the next station or a larger tool is mounted and a larger bore machined, and the process repeated until the desired bore geometry is reached. The number of tools required to achieve the desired bore size is dependent on the workpiece material, the amount of stock to be removed and geometrical requirements, with four to six tool pieces being common. Each tool is progressively larger than the last, but in diminishing increments; as the stock removal is reduced, so is the tool's diamond grit size.\nThe process is similar to honing, in that the tool follows the existing center line of the bore. To make sure the tool follows the existing center line, the tool, workpiece, or both are allowed to float. Usually just the workpiece is floated, but both pieces may be floated to get the tightest tolerances, however this greatly increases complexity. For workpieces that are larger than approximately it may be more feasible to float the tool. The process can achieve a size tolerance of and a geometry tolerance of in production.\nMachine tool.\nSingle-pass bore finishing is not usually done in a milling machine for several reasons. Firstly, most milling machines have only one spindle, so changing the tool more than four to six times can increase cycle times significantly. Secondly, most workpieces that require this process are made on horizontal machining centers (HMC), which reduces float-ability due to gravity. Thirdly, the lubrication may not be sufficient, which can lead to material build-up between diamonds, diminishing the tool's effectiveness. Finally, if any chips remain from previous operations they can ruin the tool.\nInstead, typically a dedicated machine tool is used. It has four to eight spindles and usually a rotary table. The cycle time for this type of setup is determined by the longest individual operation, which in this situation is determined by how long it takes to plunge and retract the tool through the bore. Throughput can be increased by completing two workpieces on each cycle; this is achieved by having two identical stations for each tool size so that two workpieces can be operated on concurrently.\nAdvantages and disadvantages.\nThere is little downtime due to tool changes because tools usually last from tens of thousands of passes to over a million. The perishable tool cost can be as low as a 0.01 USD per bore for very large quantity runs. To make the process cost effective minimum runs would be on the order of one to two hundred parts with several runs each year.\nSingle-pass bore finishing is not well suited for blind holes because the tool has a tapered lead on it which prevents the bottom of the hole from being finished. The process can be performed on blind holes, but it requires an alternative tool design and suitable manufacturing conditions. A better alternative is ID grinding.\nCommonly processed materials include soft and hard steels, aluminum, bronze, brass, ceramics, and chrome. Note that gummy grades of stainless steel, aluminum, and all but the hardest grades of plastic are much tougher for this process. The gumminess problem can be overcome with special oil based cutting fluids. Also, the process does not work well on thin-walled workpieces owing to a tendency to expand when the tool is inserted.\nThis method of bore finishing is better suited for bores with relatively low length-to-diameter ratios, usually less than 2:1. However, if there are cross-holes, or other interruptions in the bore, then a ratio greater than 2:1 is possible, because swarf and fluids may be expelled via these routes. This process is also not well suited for surfaces that require cross-hatching.", "Engineering,_Manufacturing": 0.9999923706, "qwen": "Yes"}
{"id": "65593614", "revid": "41450519", "url": "https://en.wikipedia.org/wiki?curid=65593614", "title": "Air Squared", "text": "Air Squared is a vertically integrated research and development (R&D) original equipment manufacturing (OEM) firm headquartered in Thornton, Colorado. Its operations include the design, fabrication, and production of oil-free scroll compressors, vacuum pumps, and expanders. Organized in two divisions, Air Squared Manufacturing handles volume assembly and production whereas Air Squared Inc. handles research and development. \nHistory.\nIn 1991, Robert Shaffer founded Air Squared Inc. in Cincinnati, Ohio to license oil-free scroll compressors for medical device applications. Air Squared's first patent was awarded in 1997 titled \"Scroll compressor having a tip seal\". In 2001, Air Squared Manufacturing Inc. was formed in Broomfield, Colorado. Operations were consolidated when both entities merged to form Air Squared Group Inc. in 2016. In 2022, all operations were relocated to Thornton, Colorado.", "Engineering,_Manufacturing": 0.9999922514, "qwen": "Yes"}
{"id": "14148719", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=14148719", "title": "Permanent mold casting", "text": "Permanent mold casting is a metal casting process that employs reusable molds (\"permanent molds\"), usually made from metal. The most common process uses gravity to fill the mold, however gas pressure or a vacuum are also used. A variation on the typical gravity casting process, called slush casting, produces hollow castings. Common casting metals are aluminium, magnesium, and copper alloys. Other materials include tin, zinc, and lead alloys and iron and steel are also cast in graphite molds.\nTypical products are components such as gears, splines, wheels, gear housings, pipe fittings, fuel injection housings, and automotive engine pistons.\nProcess.\nThere are four main types of permanent mold casting: gravity, slush, low-pressure, and vacuum.\nGravity process.\nThe gravity process begins by preheating the mold to 150–200 °C (300–400 °F). to ease the flow and reduce thermal damage to the casting. The mold cavity is then coated with a refractory material or a mold wash, which prevents the casting from sticking to the mold and prolongs the mold life. Any sand or metal cores are then installed and the mold is clamped shut. Molten metal is then poured into the mold. Soon after solidification the mold is opened and the casting removed to reduce chances of hot tears. The process is then started all over again, but preheating is not required because the heat from the previous casting is adequate and the refractory coating should last several castings. Because this process is usually carried out on large production run work-pieces automated equipment is used to coat the mold, pour the metal, and remove the casting.\nThe metal is poured at the lowest practical temperature in order to minimize cracks and porosity. The pouring temperature can range greatly depending on the casting material; for instance zinc alloys are poured at approximately , while Gray iron is poured at approximately .\nMold.\nMolds for the casting process consist of two halves. Casting molds are usually formed from gray cast iron because it has about the best thermal fatigue resistance, but other materials include steel, bronze, and graphite. These metals are chosen because of their resistance to erosion and thermal fatigue. They are usually not very complex because the mold offers no collapsibility to compensate for shrinkage. Instead the mold is opened as soon as the casting is solidified, which prevents hot tears. Cores can be used and are usually made from sand or metal.\nAs stated above, the mold is heated prior to the first casting cycle and then used continuously in order to maintain as uniform a temperature as possible during the cycles. This decreases thermal fatigue, facilitates metal flow, and helps control the cooling rate of the casting metal.\nVenting usually occurs through the slight crack between the two mold halves, but if this is not enough then very small vent holes are used. They are small enough to let the air escape but not the molten metal. A riser must also be included to compensate for shrinkage. This usually limits the yield to less than 60%.\nMechanical ejectors in the form of pins are used when coatings are not enough to remove casts from the molds. These pins are placed throughout the mold and usually leave small round impressions on the casting.\nSlush.\n\"Slush casting\" is a variant of permanent molding casting to create a \"hollow casting\" or \"hollow cast\". In the process the material is poured into the mold and allowed to cool until a shell of material forms in the mold. The remaining liquid is then poured out to leave a hollow shell. The resulting casting has good surface detail but the wall thickness can vary. The process is usually used to cast ornamental products, such as candlesticks, lamp bases, and statuary, from low-melting-point materials. A similar technique is used to make hollow chocolate figures for Easter and Christmas.\nThe method was developed by William Britain in 1893 for the production of lead toy soldiers. It uses less material than solid casting, and results in a lighter and less expensive product. Hollow cast figures generally have a small hole where the excess liquid was poured out.\nSimilarly, a process called \"slush molding\" is used in automotive dashboard manufacture, for soft-panel interiors with artificial leather, where a free-flowing (which behave like a liquid) powder plastic compound, either PVC or TPU, is poured into a hot, hollow mold and a viscous skin forms. Excess slush is then drained off, the mold is cooled, and the molded product is stripped out.\nLow-pressure.\nLow-pressure permanent mold (\"LPPM\") casting uses a gas at low pressure, usually between 3 and 15 psi (20 to 100 kPa) to push the molten metal into the mold cavity. The pressure is applied to the top of the pool of liquid, which forces the molten metal up a refractory pouring tube and finally into the bottom of the mold. The pouring tube extends to the bottom of the ladle so that the material being pushed into the mold is exceptionally clean. No risers are required because the applied pressure forces molten metal in to compensate for shrinkage. Yields are usually greater than 85% because there is no riser and any metal in the pouring tube just falls back into the ladle for reuse.\nThe vast majority of LPPM casting are from aluminum and magnesium, but some are copper alloys. Advantages include very little turbulence when filling the mold because of the constant pressure, which minimizes gas porosity and dross formation. Mechanical properties are about 5% better than gravity permanent mold castings. The disadvantage is that cycles times are longer than gravity permanent mold castings.\nVacuum.\nVacuum permanent mold casting retains all of the advantages of LPPM casting, plus the dissolved gases in the molten metal are minimized and molten metal cleanliness is even better. The process can handle thin-walled profiles and gives an excellent surface finish. Mechanical properties are usually 10 to 15% better than gravity permanent mold castings. The process is limited in weight to .\nAdvantages and disadvantages.\nThe main advantages are the reusable mold, good surface finish, good dimensional accuracy, and high production rates. Typical tolerances are 0.4 mm for the first 25 mm (0.015 in for the first inch) and 0.02 mm for each additional centimeter (0.002 in per in); if the dimension crosses the parting line add an additional . Typical surface finishes are 2.5 to 7.5 μm (100–250 μin) RMS. A draft of 2 to 3° is required. Wall thicknesses are limited to . Typical part sizes range from 100 g to 75 kg (several ounces to 150 lb). Other advantages include the ease of inducing directional solidification by changing the mold wall thickness or by heating or cooling portions of the mold. The fast cooling rates created by using a metal mold results in a finer grain structure than sand casting. Retractable metal cores can be used to create undercuts while maintaining a quick action mold.\nThere are three main disadvantages: high tooling cost, limited to low-melting-point metals, and short mold life. The high tooling costs make this process uneconomical for small production runs. When the process is used to cast steel or iron the mold life is extremely short. For lower melting point metals the mold life is longer but thermal fatigue and erosion usually limit the life to 10,000 to 120,000 cycles. The mold life is dependent on four factors: the mold material, the pouring temperature, the mold temperature, and the mold configuration. Molds made from gray cast iron can be more economical to produce but have short mold lives. On the other hand, molds made from H13 tool steel may have a mold life several times greater. The pouring temperature is dependent on the casting metal, but the higher the pouring temperature the shorter the mold life. A high pouring temperature can also induce shrinkage problems and create longer cycle times. If the mold temperature is too low misruns are produced, but if the mold temperature is too high then the cycle time is prolonged and mold erosion is increased. Large differences in section thickness in the mold or casting can decrease mold life as well.", "Engineering,_Manufacturing": 0.9999970198, "qwen": "Yes"}
{"id": "1316916", "revid": "37371155", "url": "https://en.wikipedia.org/wiki?curid=1316916", "title": "Toyota Industries", "text": " is a Japanese machine maker. Originally, and still actively , a manufacturer of automatic looms, it is the company from which Toyota Motor Corporation developed. It is the world's largest manufacturer of forklift trucks measured by revenues.\nHistory.\n1920s.\nThe company was founded on 18 November 1926 as Toyoda Automatic Loom Works, Ltd. by Sakichi Toyoda, the inventor of a series of manual and machine-powered looms. The most significant of these was the 1924 Toyoda Automatic Loom, Type G, a completely automatic high-speed loom featuring the ability to change shuttles without stopping and dozens of other innovations. At the time it was the world's most advanced loom, delivering a clear improvement in quality and a twenty-fold increase in productivity.\nIn 2007, this machine was registered as item No. 16 in the Mechanical Engineering Heritage of Japan as \"a landmark achievement that advanced the global textile industry and laid the foundation for the development of the Toyota Group.\"\n1930s.\nIn 1933, the company established its automobile department, led by Kiichiro Toyoda, the eldest son of Sakichi Toyoda. This department was spun off as Toyota Motor Co., Ltd. in 1937 and is now known as Toyota Motor Corporation. Toyota Industries is one of 13 core companies of the Toyota Group. The company owns 8.48% of Toyota Motor and is the largest shareholder (excluding trust revolving funds). As a countermeasure against hostile merger and acquisition attempts, Toyota Motor currently holds 24.92% of common stock of its origin Toyota Industries.\n1940s.\nIn 1940, the steel production department of Toyota Industries was spun off as Toyota Steel Works Ltd. (present Aichi Steel Corporation). In 1944, Toyota Industries's Obu plant, which produces castings, began operations. Five years later, the Toyota Industries stock was listed on the Tokyo, Osaka, and Nagoya Stock Exchanges.\n1950s.\nIn 1952, Toyota Industries began producing press die for automobiles. One year later the Kyowa plant began to assemble automobiles and produce engines. In 1956 Toyota unveiled the Model LA 1-ton lift truck, this was the company's first lift truck model. In 1957, Toyota Industries began producing D-type diesel engines. That same year, it launched the Model LAT .85-ton towing tractor. In the final year of the decade, Toyota Industries began producing the P-type gasoline engine.\n1960s.\nIn 1960, the Kyowa plant was modified to only assemble lift trucks. That same year, the company began producing the shovel loader and three cylinder crank shaft type compressor. That same year, Toyota Industries' Development Laboratories and Toyota Central Research were established with funds from ten Toyota group companies. In 1964, Toyota Industries was recognized by Japan's Ministry of International trade and industry as one of the first Japanese companies to export. Toyota Industries also unveiled their new automated continuous spinning system. In 1967, the Toyota Publica entered into production at the company's Nagakusa plant. Toyota Industries had a monthly output of more than 1,000 units.\n1970s.\nIn 1971, the company started assembling the Corolla. In 1973, Toyota Industries reached an output of 3,000 units. One year later, in 1974, production began on car air-conditioning compressors.\n1980s.\nIn 1980, the company started producing the JA air. By 1984, the engine division of Toyota Industries was separated from the vehicle division. In 1986, Toyota Industries received the Deming Application prize for quality control implementation. In 1988 Toyota Industrial Equipment is created in Indiana, US.\n1990s.\nIn 1991, Toyota Industries reached the landmark of 5 million units produced. A year later, it set up an Environmental Committee.\nCurrent business.\nToyota Industries is active in five business areas: automotive, materials handling, electronics, logistics, and textile machinery.\nToyota-branded forklifts from Toyota Industries share the same logo as Toyota automobiles from Toyota Motor Corporation and are manufactured at the Toyota Material Handling Inc. (TMH), previously known as Toyota Industrial Equipment Manufacturing (TIEM), facility in Columbus, Indiana, for the US market. \nToyota Material Handling USA (TMHU) was formally a separate company, breaking out dealer and sales divisions of the North American business. Toyota Industrial Equipment Manufacturing (TIEM) was formally focused on engineering, manufacturing and responsible for the daily production of forklifts. In 2018, these two divisions merged, combining the sales and manufacturing business functions into one business entity, now known as Toyota Material Handling Inc. (TMH).\nToyota Industries Corporation is under contract from Toyota Motor Corporation for the production of the Toyota RAV4. The company manufactures automotive engines for use in Toyota-branded automobiles such as Avensis, Corolla, Crown, and Land Cruiser.\nIn 2000, Toyota Industries acquired the Swedish-based forklift truck corporation BT Industries, alongside BT's subsidiaries The Raymond Corporation and CESAB. Combined with Toyota Industries' materials handling division, this created the largest forklift company in the world, Toyota Material Handling Corporation.\nIn October 2012, Toyota Industries acquired Cascade Corp., a maker of attachments for forklifts, for a price of $728 million.\nIn 2017, Toyota Industries acquired Vanderlande, a manufacturer of automated material handling equipment, mostly for airports.\nLooms.\nIn 2020, Toyota Industries was manufacturing two state-of-the-art looms: the JAT810 (air jet loom) and LWT810 (water jet loom). Both looms operate without shuttles. The water jet loom throws the weft through the warp threads using water, and thus can only be used with synthetic fibers. The air jet loom uses air to throw the weft, and thus can be use with any fiber.\nStock exchange.\nThe company's shares are traded on the Tokyo Stock Exchange under symbol 6201.T.", "Engineering,_Manufacturing": 1.0000019073, "qwen": "Yes"}
{"id": "33902190", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=33902190", "title": "Kaizen costing", "text": "Kaizen costing is a cost reduction system used after a product's design has been completed and it is in production. Business professor Yasuhiro Monden defines kaizen costing as \nThe Shogakukan Dictionary's original definition of Kaizen is translated as \"“The act or making bad points better”.\" In English, the more popular definition of Kaizen is “Change for Better”. Many believe that the Kaizen meaning is “continuous improvement” but, Kaizen is a result of continuous improvement. It exists at the employee's level. The employee's goal is to reach their potential, challenge the status quo and achieve continual improvement.\nPrior to kaizen costing, when the products are under the development phase, target costing is applied. After targets have been set, they are continuously updated to display past improvements and the projected (expected) improvements.\nMonden has described two types of kaizen costing:\nAdopting kaizen costing requires a change in the method of setting standards.\nKaizen costing focuses on \"cost reduction\" rather than \"cost control\".\nTypes of cost under consideration.\nKaizen costing takes into consideration costs related to the manufacturing stage, which include:", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "33688973", "revid": "11308236", "url": "https://en.wikipedia.org/wiki?curid=33688973", "title": "Microscanner", "text": "A microscanner, or micro scanning mirror, is a microoptoelectromechanical system (MOEMS) in the category of micromirror actuators for dynamic light modulation. Depending upon the type of microscanner, the modulatory movement of a single mirror can be either translatory or rotational, on one or two axes. In the first case, a phase shifting effect takes place. In the second case, the incident light wave is deflected.\nMicroscanners are different from spatial light modulators and other micromirror actuators which need a matrix of individually addressable mirrors in order to accomplish the desired modulation at any yield. If a single array mirror accomplishes the desired modulation but is operated in parallel with other array mirrors to increase light yield, then the term microscanner array is used.\nCharacteristics.\nCommon chip dimensions are 4 mm × 5 mm for mirror diameters between 1 and 3 mm. Larger mirror apertures with side measurements of up to approx. 10 mm × 3 mm can also be produced. The scan frequencies depend upon the design and mirror size and range between 0.1 and 50 kHz. The deflection movement is either resonant or quasi-static. With microscanners that are capable of tilting movement, light can be directed over a projection plane.\nMany applications requires that a surface is addressed instead of only a single line. For these applications, actuation using a Lissajous pattern can accomplish sinusoidal scan motion, or double resonant operation. Mechanical deflection angles of micro scanning devices reach up to ±30°. Translational (piston type) microscanners, can attain a mechanical stroke of up to approx. ±500 μm. This configuration is energy efficient, but requires complicated control electronics. For high end display applications the common choice is raster scanning, where a resonant scanner (for the longer display dimension) is paired with quasi-static scanner (for the shorter dimension).\nDrive principles.\nThe required drive forces for the mirror movement can be provided by various physical principles. In practice, the relevant principles for driving such a mirror are the electromagnetic, electrostatic, thermoelectric, and piezoelectric effects. Because the physical principles differ in their advantages and disadvantages, the driving principle is chosen according to the application. Specifically, the mechanical solutions required for resonant scanning are very different for those of quasi-static scanning. Thermoelectric actuators are not applicable for high-frequency resonant scanners, but the other three principles can be applied to the full spectrum of applications.\nFor resonant scanners, one often employed configuration is the indirect drive. In an indirect drive, a small motion in a larger mass is coupled to a large motion in a smaller mass (the mirror) through mechanical amplification at a favorable mode shape. This is in contrast to the more common direct drive, where the actuator mechanism moves the mirror directly. Indirect drives have been implemented for electromagnetic, electrostatic, as well as piezoelectric actuators. Existing piezoelectric scanners are more efficient using direct drive.\nElectrostatic actuators offer high power similar to electromagnetic drives. In contrast to an electromagnetic drive, the resulting drive force between the drive structures cannot be reversed in polarity. For the realization of quasi-static components with positive and negative effective direction, two drives with positive and negative polarity are required. As a rule of thumb, vertical comb drives are utilized here. Nevertheless, the highly non-linear drive characteristics in some parts of the deflection area can be hindering for controlling the mirror properly. For that reason many highly developed microscanners today utilize a resonant mode of operation, where an eigenmode is activated. Resonant operation is the most energy-efficient. For beam positioning and applications which are to be static-actuated or linearized-scanned, quasi-static drives are required and therefore of great interest.\nMagnetic actuators offer very good linearity of the tilt angle versus the applied signal amplitude, both in static and dynamic operation. The working principle is that a metallic coil is placed on the moving MEMS mirror itself and as the mirror is placed in a magnetic field, the alternating current flowing in the coil generates Lorentz force that tilts the mirror. Magnetic actuation can either be used for actuating 1D or 2D MEMS mirrors. Another characteristic of the magnetically actuated MEMS mirror is the fact that low voltage is required (below 5V) making this actuation compatible with standard CMOS voltage. An advantage of such an actuation type is that MEMS behaviour does not present hysteresis, as opposed to electrostatic actuated MEMS mirrors, which make it very simple to control. Power consumption of magnetically actuated MEMS mirrors can be as low as 0.04 mW.\nThermoelectric drives produce high driving forces, but they present a few technical drawbacks inherent to their fundamental principle. The actuator has to be thermally well insulated from the environment, as well as being preheated in order to prevent thermal drift due to environmental influences. That is why the necessary heat output and power consumption for a thermal bimorph actuator is relatively high. One further disadvantage is the comparably low displacement which needs to be leveraged to reach usable mechanical deflections. Also thermal actuators are not suitable for high frequency operation due to significant low pass behaviour.\nPiezoelectric drives produce high force, but as with electrothermal actuators the stroke length is short. Piezoelectric drives are, however, less susceptible to thermal environmental influences and can also transmit high-frequency drive signals well. To achieve the desired angle some mechanism utilizing mechanical amplification will be required for most applications. This has proven to be difficult for quasi-static scanners, although there are promising approaches in the literature using long meandering flexures for deflection amplification. For resonant rotational scanners, on the other hand, scanners using piezoelectric actuation combined with an indirect drive are the highest performer in terms of scan angle and working frequency. However, the technology is newer than electrostatic and electromagnetic drives and remains to be implemented in commercial products.\nFields of Application.\nApplications for tilting microscanners are numerous and include:\nSome of the applications for piston type microscanners are:\nManufacture.\nMicroscanners are usually manufactured with surface or bulk micromechanic processes. As a rule, silicon or BSOI (bonded silicon on insulator) are used.\nAdvantages and disadvantages of microscanners.\nMicroscanners are smaller, lower mass, and consume smaller amounts of power compared to macroscopic light modulators such as galvanometer scanners. Additionally, microscanners can be integrated with other electronic components such as position sensors. Microscanners are resistant to environmental influences, and can tolerate humidity, dust, physical shocks in some models up to 2500g, and can operate in temperatures from -20 °C to +80 °C.\nWith current manufacturing technology microscanners can suffer from high costs and long lead times to delivery. This is an active area of process improvement", "Engineering,_Manufacturing": 0.9999710321, "qwen": "Yes"}
{"id": "12499952", "revid": "21171569", "url": "https://en.wikipedia.org/wiki?curid=12499952", "title": "Equal channel angular extrusion", "text": "Equal channel angular extrusion (ECAE) called also equal channel angular pressing (ECAP) is one technique from the Severe Plastic Deformation (SPD) group, aimed at producing Ultra Fine Grained (UFG) material. Developed in the Soviet Union in 1973 by Segal.  However, the dates are not always consistent. In industrial metalworking, it is an extrusion process, The technique is able to refine the microstructure of metals and alloys, thereby improving their strength according to the Hall-Petch relationship. This process improves not only the strength but also other properties such as corrosion and wear resistance of alloys and compounds. \nECAE is unique because significant cold work can be accomplished without reduction in the cross sectional area of the deformed workpiece. In conventional deformation processes like rolling, forging, extrusion, and drawing, strain is introduced by reduction in the cross sectional area. ECAE produces significant deformation strain without reducing the cross sectional area. This is accomplished by extruding the work piece around a corner. For example, a square cross section bar of metal is forced through a channel with a 90° degree angle. The cross section of the channel is equal on entry and exit. The complex deformation of the metal as it flows around the corner produces very high strain. Because the cross section remains the same, a work piece can be extruded multiple times with each pass introducing additional strain. \nDie design is critical because of the large forces required. \nTo reduce the friction of the pushed sample is lubricated with grease for example mixture of graphite and oil, and to reduce the forces, the process is sometimes carried out at elevated temperatures but then recrystallization can occur which can also leads to excessive grain growth at elevated temperature. \nThere are some modifications of the process e.g. incremental ECAP (I-ECAP) for the production of continuous products.\nProcess routes.\nThe process can be carried out in multiple passes. According to the rotation angle and direction between next passes, there can be four fundamental process routes named A, Ba, Bc, and C:\nFinite element method in the ECAE process.\nThe behave during deformation and flow of the material, are analyzed by scientists and there are many articles on computer simulation, finite element method is one of the important approaches to understand the deformation occurring in the ECAE process.\nSee also.\nSevere plastic deformation\nStrengthening mechanisms of materials", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "66897509", "revid": "2278355", "url": "https://en.wikipedia.org/wiki?curid=66897509", "title": "Arc spring", "text": "The arc spring (also known as - bow spring, curved spring, circular spring or \"banana\" spring) is a special form of coil spring which was originally developed for use in the dual-mass flywheel of internal combustion engine drive trains. The term \"arc spring\" is used to describe pre-curved or arc-shaped helical compression springs. They have an arc-shaped coil axis.\nFunction.\nLike other technical springs, arc springs are based on the fundamental principle of storing mechanical work in the form of potential energy and the ability to release this energy again. The force is applied through the ends of the spring. A torque formula_1 can be transmitted around an axis via the force formula_2 directed along this helical axis and the lever arm to the system center point formula_3. The wire of the arc spring is mainly subjected to torsional stress.\nSupport.\nAn arc spring requires suitable support to transmit torque. The support is usually provided from the outside in the form of an arcuate channel (sliding shell) or radially shaped support plates. This prevents buckling of the arc spring. Another result of this support is a hysteresis between the loading and unloading curves in the characteristic curve. This results from the friction of the spring on the radial support and is an intended effect to achieve damping in the system.\nArc spring systems.\nAs with compression springs, spring systems can also be used for arc springs. The main designs are series and parallel connection. With these, single-stage or multi-stage spring characteristics can be achieved. In order to make optimum use of the available space, systems consisting of inner and outer arc springs are often used.\nIn addition, the spring characteristic can be influenced by other parameters such as the cross-sectional geometry of the wire, the coil diameter or the number of coils. CAD configurators, which generate a CAD model after entering certain parameters, can contribute to optimal design.\nApplications.\nThe arc spring is suitable for static and quasi-static as well as dynamic applications. Examples include:\nMaterials and their standardization.\nIn principle, the spring steels used for ordinary coil springs can also be used for arc springs. These are:", "Engineering,_Manufacturing": 0.9999374151, "qwen": "Yes"}
{"id": "48135647", "revid": "20611691", "url": "https://en.wikipedia.org/wiki?curid=48135647", "title": "Kemet International Limited", "text": "Kemet International Limited, based in Maidstone, Kent UK, is involved with precision lapping and polishing technology using diamond media, composite lapping plates and precision lapping and polishing machines to produce polished finishes with close tolerances. In 1998 Kemet was Britain's largest supplier and manufacturer of diamond compounds and slurries.\nKemet has four divisions covering flat lapping and polishing, Tool and Die, Metallographic and Petrographic specimen preparation and Ultrasonic cleaning with aqueous media.\nHistory.\nThe company was formed in September 1938, initially as an importer of equipment for the aircraft industry, which included precision machinery and small tools for the fabrication of ball bearing races for gyroscopes as well as woodworking machines to help manufacture the Mosquito fighter aircraft used in World War 2.\nIn 1953 manufacture started on a range of diamond abrasive pastes, which for the first time enabled precision components to be polished to a specified surface finish with guaranteed reproducible results. Developed in the first instance for use in the production of moulds and tools for the rapidly expanding plastics industry, as well as the precision polishing of hard materials and ceramics, diamond pastes now form just part of the Kemet product range.\nIn the early 1970s, a series of metal/resin composite lapping plates were developed which meant that for the first time a wide range of materials, including materials of different harnesses, could be flat lapped and polished to a higher specification than was previously achievable.\nShortly afterwards, a new division was set up to concentrate specifically on flat lapping using the technology of the Kemet composite plates. The result of this new venture was the introduction of a range of liquid diamond products and precision flat lapping machines developed for production lapping applications.\nIn February 1989, Kemet International obtained ISO 9001:2008 certification for the manufacture of diamond lapping and polishing products. This was extended soon afterwards to include Kemet composite lapping plates.\nIn 2009, Kemet International Limited won the . In 2014 Kemet International won the southern regional categories of the British Chambers of Commerce Awards 2014.\nSubsidiary companies.\nKemet Europe was established in 1965 in the Netherlands, Kemet Australia in 1972, and Kemet Far East in Singapore in 1983. Kemet Far East obtained ISO 9001:2008 certification in July 2000.\nThe turnover of Kemet International and the subsidiary companies was £15.4m ($25m) in September 2014\nBetween 2002 -2008, Kemet International set up Kemet China as a sales company and entered into joint ventures to establish Kemet Japan and Kemet Korea.\nServices.\nKemet offers training courses both in- house and on the customer’s premises covering all lapping and polishing activities. Kemet also offers a contract lapping service for customers who do not want to buy the equipment. Contract lapping is also covered under ISO 9001:2008\nResearch and development.\nKemet has set up dedicated research and development facilities in the UK to optimise customers’ processes for lapping and polishing application and to develop new products.\nRecently new process developments facilities have been opened covering metallographic and petrographic sample preparation and ultrasonic cleaning with aqueous- based media.\nIn 2013 new R&D facilities were built in Singapore to cover high precision lapping and polishing process development for the electronics industry in SE Asia and China", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "33095405", "revid": "13266769", "url": "https://en.wikipedia.org/wiki?curid=33095405", "title": "Calcium stearoyl-2-lactylate", "text": "Calcium stearoyl-2-lactylate (calcium stearoyl lactylate or CSL) or E482 is a versatile, FDA approved food additive. It is one type of a commercially available lactylate. CSL is non-toxic, biodegradable, and typically manufactured using biorenewable feedstocks. Because CSL is a safe and highly effective food additive, it is used in a wide variety of products from baked goods and desserts to packaging.\nAs described by the Food Chemicals Codex 7th edition, CSL is a cream-colored powder. CSL is currently manufactured by the esterification of stearic acid and lactic acid with partial neutralization using food-grade hydrated lime (calcium hydroxide). Commercial grade CSL is a mixture of calcium salts of stearoyl lactic acid, with minor proportions of other salts of related acids. The HLB for CSL is 5.1. It is slightly soluble in hot water. The pH of a 2% aqueous suspension is approximately 4.7.\nFood labeling requirements.\nTo be labeled as CSL for sale within the United States, the product must conform to the specifications detailed in 21 CFR 172.844. In the EU, the product must conform to the specifications detailed in Regulation (EC) No 96/77. Tests for these specifications can be found in the Food Chemical Codex. Acceptance criteria for these two regions are as follows:\nTo be labeled as CSL for sale in other regions, the product must conform to the specifications detailed in that region's codex.\nFood applications and maximum use levels.\nCSL finds widespread application in baked goods, cereals, pastas, instant rice, desserts, icings, fillings, puddings, toppings, sugar confectionaries, powdered beverage mixes, creamers, cream liqueurs, dehydrated potatoes, snack dips, sauces, gravies, chewing gum, dietetic foods, minced and diced canned meats, and \"mostarda di frutta\". In the United States, approved uses and use levels are described in 21 CFR 172.844, 21 CFR 176.170 and 21 CFR 177.120. while the corresponding regulations in the EU are listed in Regulation (EC) No 95/2.\nThe largest application of CSL is in yeast leavened bakery products. Although CSL was introduced to the market first, most applications use SSL. The main reason for the preference of SSL over CSL is that CSL has less crumb softening effects than SSL. However, CSL is still preferred in some applications, such as lean hearth bread-type formulations. In these applications, CSL is preferred because CSL performs better than SSL as a dough strengthener, while the finished product does not require a soft crumb or a perfectly symmetrical loaf shape.", "Engineering,_Manufacturing": 0.9998414516, "qwen": "Yes"}
{"id": "33113928", "revid": "486612", "url": "https://en.wikipedia.org/wiki?curid=33113928", "title": "Precision mechanics", "text": "Precision mechanics (also \"fine mechanics\") is an engineering discipline that deals with the design and construction of smaller precision machines, often including measuring and control mechanisms of different kinds.\nThe study may be further defined as the practices of rigid body kinematics to the positioning and holding of objects on the micrometre scale and smaller.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "12187254", "revid": "34706848", "url": "https://en.wikipedia.org/wiki?curid=12187254", "title": "Discbox slider", "text": "The discbox slider (also called DBS) is a 100% carton board optical disc packaging concept developed by the multinational paper and board company Stora Enso. \nThe case is comparable with the plastic jewel or Amaray case when it comes to size, but has more of the features of the LP style cases in terms of weight and printability. The DBS case opens up from the side by moving the slider part (on which the disc is resting) from the sleeve. The Discbox Slider is also considered as an environmentally friendly prerecorded media packaging option as it is 100% recyclable and manufactured using sustainable processes.\nThe Discbox slider has two packaging formats: the small-sized DBS CD for CD-sized packaging, and the DBS DVD for DVD-sized packaging (a DVD case which is available both in normal and slim size). The DBS CD case can hold 1–2 discs and a booklet, whereas the DBS DVD cases can hold 1–3 discs and booklet. The DVD-sized case is increasingly being adopted for Blu-ray releases. The Discbox Slider (DBS) packaging is currently being used by record labels and movie studios worldwide.\nMany covermount CDs released in British magazine Mixmag used to be packaged in a Discbox slider. This format replaced the standard jewel case which in turn was replaced by a simple cardboard sleeve.", "Engineering,_Manufacturing": 0.9986627102, "qwen": "Yes"}
{"id": "12199703", "revid": "7034620", "url": "https://en.wikipedia.org/wiki?curid=12199703", "title": "Process manufacturing", "text": "Process manufacturing is a branch of manufacturing that is associated with formulas and manufacturing recipes, and can be contrasted with discrete manufacturing, which is concerned with discrete units, bills of materials and the assembly of components. Process manufacturing is also referred to as a 'process industry' which is defined as an industry, such as the chemical or petrochemical industry, that is concerned with the processing of bulk resources into other products.\nProcess manufacturing is common in the food, beverage, chemical, pharmaceutical, nutraceutical, consumer packaged goods, cannabis, and biotechnology industries. In process manufacturing, the relevant factors are ingredients, not parts; formulas, not bills of materials; and bulk materials rather than individual units. Although there is invariably cross-over between the two branches of manufacturing, the major contents of the finished product and the majority of the resource intensity of the production process generally allow manufacturing systems to be classified as one or the other. For example, a bottle of juice is a discrete item, but juice is process manufactured. The plastic used in injection moulding is process manufactured, but the components it is shaped into are generally discrete, and subject to further assembly.\nFormulation.\nFormulation is a simple concept, but it is often incorrectly equated with a bill of materials. Formulation specifies the ingredients and the amounts (e.g., pounds, gallons, liters) needed to make the product. The first thing to recognize is that to be able to work with a formula, the units of measure must correspond; a flexible unit of measure conversion engine running under an ERP software cover is needed. Furthermore, conversion rules must be specified to account for the unique requirements of the business in question. This formulation then needs to be scaled up to the development and then manufacturing scales, and must often be transferred and validated in different manufacturing sites around the world. \nThe proportions of ingredients in a formula also highlight the need for another feature, namely scalability. A formula to make 500 liters of a chemical must be scalable to make 250 liters or 1,000 liters. Another aspect of scalability is that it makes possible manufacturing based on how much of an ingredient is available. An example will illustrate this point. If you are making a car and only have two of the required four tires, you cannot make half a car. In other words, you must have all the parts in the required quantities to make the finished product; they are not scalable. But in process manufacturing, if you want to make 1,000 gallons of soda and you only have 500 gallons of the required 1,000 gallons of carbonated water, you have the option of making half as much soda. In process manufacturing you can make as much of a finished product as is specified in the formula for the smallest quantity in stock of one of the ingredients.\nPackaging.\nA packaging recipe is similar to a formula, but rather than describing the proportion of ingredients, it specifies how the finished product gets to its final assembly. A packaging recipe addresses such things as containers, labels, corrugated cartons, and shrink-wrapping. In process manufacturing, the finished product is usually produced in bulk, but is rarely delivered in bulk form to the customer. For example, the beverage manufacturer makes soda in batches of thousands of gallons. However, a consumer purchases soda in 12-ounce aluminum cans, or in 16-ounce plastic bottles, or in 1-liter bottles. And a restaurateur may have the option of getting a 5- or 50-gallon metal container with the beverage in syrup form, so that carbonated water can be added later.\nWhy is this concept important? Compare how often Coca-Cola changes the formula for Coke with how often the packaging is changed. If the formula and packaging recipes are linked, then every time the packaging changes, the formula would need modification. Likewise, when the formula is changed, all of the packaging recipes would have to be changed. This increases maintenance costs and chances for error. In process manufacturing, the formula for making the product and the recipe for packaging the product exist in separate structures to reduce the ongoing maintenance function. There is a difference between discrete manufacturing and process manufacturing in terms of flow patterns. An example given is that discrete manufacturing follows an \"A\" type process and process manufacturing follows a “V” type process. \nIn the production cycle, a work order or process order is issued to make the product in bulk. Separate pack orders are issued to signify how the bulk material is to be containerized and shipped to the customer. This is important in process industries that make “brite” stock or private labels. For example, large grocery chains sell products, such as soups, soda, and meats, under their own brand names, hence \"private labels\". But these chains do not have their own manufacturing plants; they contract for these products. In the case of soups, process manufacturers create and warehouse nondescript, unlabeled (hence “brite”) aluminum cans of soup. (Since the cans are filled, sealed, and then cooked under pressure, their shelf life is long.)\nBy separating the product formula from a packaging recipe, a production or process order can be issued to make and store the cans of soup and later, when the customer is ready to order soup, a work order can be issued to label the cans according to customer specifications before they are shipped to the store. Thus segregation of the formula and pack recipe makes the world of process manufacturing efficient and effective.\nProcess manufacturing systems and methodologies.\nEnterprise resource planning\nJust like the products that they produce, discrete manufacturing and process manufacturing use different Enterprise resource planning (ERP) systems which have different focal points and solve different problems. For the same reason that the proverbial square peg does not fit in the round hole, ERP software geared toward discrete manufacturing, or even hybrid manufacturing will not work smoothly in a process manufacturing setting. With process manufacturing, the end-product is unable to be broken down to its original ingredients, for example beer or pasta sauce. Thus, the ERP software must be able to account for these intricacies in its ability to convert and transform raw materials to finished goods. Critical aspects such as recipe formulation, forward and backward lot traceability, handling of mixed units of measure and conversion, raw material calculations, and scalable batch tickets with revision tracking and recording of manufacturing steps and production notes are specific to process manufacturers and key functionality of process manufacturing ERP systems. An example is the SAP module, Production Planning - Process Industries (PP-PI). \nIn Process Inspections and Statistical Process Control\nIn process inspection for process manufacturing refers to inspection at any point in producing a product, and is also referred to as in process product verification. The objective of in process inspection is to ensure the requirements of the product are being met before they are finalized and continue to the next stage. Identifying a problem at an early stage in the production process allows for correction and preventative action to avoid wasted time and resources at the end of a production run.\nStatistical Process Control complements process manufacturing and in process inspections to ensure that the process operates efficiently, producing more specification-conforming products with less waste (rework or scrap). \nProcess approach in Management Systems \nThe process approach is one of seven quality management principles that ISO management system standards are based on, and includes establishing the organization’s processes to operate as an\nintegrated and complete system. \nIn Food processing, complying product has to come from a process to comply, in comparison to discrete manufacturing where a finished product is inspected to comply. An example how the process approach complements a process industry is implementation of ISO 22000 as a Food Safety Management System (FSMS). The process approach involves the systematic definition and management of processes, and their interactions, so as to achieve the intended results in accordance with the food safety policy and strategic direction of the organization. Management of the processes and the system as a whole can be achieved using the PDCA cycle, with an overall focus on risk-based thinking aimed at taking advantage of opportunities and preventing undesirable results.\nFurther reading.\nSalimi, Fabienne; Salimi, Frederic, A Systems Approach to Managing the Complexities of Process Industries, 2017", "Engineering,_Manufacturing": 1.0000067949, "qwen": "Yes"}
{"id": "3261380", "revid": "21894337", "url": "https://en.wikipedia.org/wiki?curid=3261380", "title": "Atomic hydrogen welding", "text": "Atomic hydrogen welding (AHW or Athydo) is an arc welding process that uses an arc between two tungsten electrodes in a shielding atmosphere of hydrogen. The process was invented by Irving Langmuir in the course of his studies of atomic hydrogen. The electric arc efficiently breaks up the hydrogen molecules, which later recombine with tremendous release of heat, reaching temperatures from 3400 to 4000 °C. Without the arc, an oxyhydrogen torch can only reach 2800 °C. This is the third-hottest flame after dicyanoacetylene at 4987 °C and cyanogen at 4525 °C. An acetylene torch merely reaches 3300 °C. This device may be called an atomic hydrogen torch, nascent hydrogen torch or Langmuir torch. The process was also known as arc-atom welding.\nThe heat produced by this torch is sufficient to weld tungsten (3422 °C), the most refractory metal. The presence of hydrogen also acts as a shielding gas, preventing oxidation and contamination by carbon, nitrogen or oxygen, which can severely damage the properties of many metals. It eliminates the need of flux for this purpose.\nThe arc is maintained independently of the workpiece or parts being welded. The hydrogen gas is normally diatomic (H2), but where the temperatures are over near the arc, the hydrogen breaks down into its atomic form, absorbing a large amount of heat from the arc. When the hydrogen strikes a relatively cold surface (i.e. the weld zone), it recombines into its diatomic form, releasing the energy associated with the formation of that bond. The energy in AHW can be varied easily by changing the distance between the arc stream and the workpiece surface.\nIn atomic hydrogen welding, filler metal may or may not be used. In this process, the arc is maintained entirely independent of the work or parts being welded. The work is a part of the electrical circuit only to the extent that a portion of the arc comes in contact with the work, at which time a voltage exists between the work and each electrode.\nThis process is being replaced by gas metal-arc welding, mainly because of the availability of inexpensive inert gases.", "Engineering,_Manufacturing": 0.9999511242, "qwen": "Yes"}
{"id": "32115804", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=32115804", "title": "Bremen Castings", "text": "Bremen Castings, Inc (BCI) is a 4th generation family owned manufacturer of machined complete gray & ductile iron castings for heavy truck, valves & pipe fittings, pump components, compressors, lawn/garden equipment, and military contract work. BCI is headquartered in Bremen, Indiana.\nHistory.\nBremen Gray Iron Foundry was founded on March 17, 1939 by Ellis Brown, Charles W. Kling, and Harold Heckamen. The foundry originally produced fire pots, stove parts, furnace, shaker, and laundry grates for its customers. Suppliers included Hurwich Iron where they purchased cupola/steel materials, I.O. Pfeiffer Construction who helped build the foundry and install equipment, and Koontz Hardware where various supplies were purchased. All of these early suppliers are still in business today and continue to have close relationships with BCI.\nIn 1972, the company changed its name to Bremen Castings, Inc.\nStarting in the mid-1990s, Bremen Castings started to expand beyond casting. The foundry's machine shop opened in 1996 and the tool shop opened in 2009.\nBCI Defense began in December 2012 and currently manufacturers firearms and Firearm parts from 7075 aluminium alloy, specifically the AR-15 style rifle.\nMachining.\nIn 1996 BCI launched its own internal machine shop with the new addition of a facility to the existing foundry with the expectations to diversify across many markets. This forced quality and engineering to grow to be diverse in both machining and foundry. This gives BCI the advantage for both departments to communicate before the product launch for a lower total start up cost. BCI purchased its first CNC machines in 1996 and now has over 17 CNC machines in its arsenal.\nBCI continues to grow. In 2011 BCI opened its 55,000 SFT facility to house all machine centers and host all assemblies.\nBremen Castings also creates prototypes using solidification software and runs solidification simulations as a means of scrap reduction.\nFoundry.\nBremen Castings foundry produces castings made from recycled materials such as plate and structural steel and old cast products. A Cupola and medium frequency furnaces are used at the foundry for melting recycled materials to be poured into green sand molds produced by match plate molding machines. Once the metal has been cast and shaken out, the products flow through the state of the art cleaning room (mill room) then on its way to the CNC machining centers.\nEngineering.\nTo help design casting models, BCI also creates prototypes and production models using MagmaSoft solidification software. The engineers are able to pre-determine scrap issues prior to production with solidification simulations and as a result they have been able to reduce the amount of scrap produced at start up of a new product launch.\nThe engineers at Bremen Castings are a full production staff handling product design, steel weldment conversions and existing products. All tooling and fixtures can be designed and built in house. BCI Engineering software consists of: MagmaSoft Solidification software, Vero Software (Visi), and CAD/CAM/CAE software for aiding the design and manufacturing process.\nStatus Quo Sucks.\nThe Status Quo Sucks (SQS) team was created to lead BCI in its goal to implement Lean Practices and eliminate waste throughout the organization. By incorporating a cultural change to a team concept, each individual at BCI has an ownership of sustainability and improvement with everything the employee touches. When the SQS team launches an improvement project, a well rounded team is assembled and a problem or situation is strategically attacked and resolved through a group effort.\nRecycling.\nBCI has been Bremen's largest recycling plant and product producer by weight. In an effort to reduce paper usage and to increase productivity, BCI has adopted a paperless office policy, and as of 2011, BCI has eliminated 85% of paper waste through technology such as iPad, iPhone, iPod, floor monitors, and electronic filing cabinet software.", "Engineering,_Manufacturing": 0.9999934435, "qwen": "Yes"}
{"id": "7262017", "revid": "76", "url": "https://en.wikipedia.org/wiki?curid=7262017", "title": "Simplic", "text": "The Simplic was a cyclecar manufactured from 1914 onwards by George Wadden in Surrey, England. Wadden was a hairdresser who took over the business that had produced the Autotrix. The first Simplic was a 4-wheeled vehicle powered by a 5/6 hp air-cooled JAP engine. Transmission was by epicyclic gear and belt final drive. Production stopped later that year due to World War I.\nWadden redesigned the car at the end of the war, and the Simplic now featured an 8/10 hp JAP engine and twin speed chain drive. Although selling for only £185, and advertised as \"Positively the best value in Cyclecars\", production ended in 1923.", "Engineering,_Manufacturing": 0.9985250831, "qwen": "Yes"}
{"id": "7264522", "revid": "30845620", "url": "https://en.wikipedia.org/wiki?curid=7264522", "title": "Substrate mapping", "text": "Substrate mapping (or wafer mapping) is a process in which the performance of semiconductor devices on a substrate is represented by a map showing the performance as a colour-coded grid. The map is a convenient representation of the variation in performance across the substrate, since the distribution of those variations may be a clue as to their cause.\nThe concept also includes the package of data generated by modern wafer testing equipment which can be transmitted to equipment used for subsequent 'back-end' manufacturing operations.\nHistory.\n The initial process supported by substrate maps was inkless binning.\nEach tested die is assigned a bin value, depending on the result of the test. For example, a pass die is assigned a bin value of 1 for a good bin, bin 10 for an open circuit, and bin 11 for a short circuit. In the very early days of wafer test, the dies were put in different bins or buckets, depending on the test results.\nPhysical binning may no longer be used, but the analogy is still good. The next step in the process was to mark the failing dies with ink, so that during assembly only uninked dies were used for die attachment and final assembly. The inking step may be skipped if the assembly equipment is able to access the information in the maps generated by the test equipment.\nA wafer map is where the substrate map applies to an entire wafer, while a substrate map is mapping in other areas of the semiconductors process including frames, trays and strips.\nE142.\nAs with many items in the Semiconductor process area, also for this process step there are standards available. The latest and most potential standard is the E142 standard, provided by the SEMI organization. This standard has been approved via ballots for release in 2005.\nIt supports many possible substrate maps, including the ones named above. While the old standards could only support standard bin maps, representing bin information, this standard also support transfermaps, which can help in tracing back dies on strips to the locations they come from off the wafer for example.", "Engineering,_Manufacturing": 0.9998639822, "qwen": "Yes"}
{"id": "7271425", "revid": "16405059", "url": "https://en.wikipedia.org/wiki?curid=7271425", "title": "List of Boeing 787 orders and deliveries", "text": "This article lists the orders and deliveries for the Boeing 787 Dreamliner. As of December 2022, the largest airline order is by United Airlines for 170 aircraft.\nOrders and deliveries.\nOrders and deliveries by type and year.\nBoeing 787 orders and deliveries (cumulative, by year):\nOrders and deliveries .\nOrders and deliveries sortable, presorted by customer.\nData through February 2023.\nOrders and deliveries graph.\nData through February 2023.", "Engineering,_Manufacturing": 1.0000076294, "qwen": "Yes"}
{"id": "7275487", "revid": "34124079", "url": "https://en.wikipedia.org/wiki?curid=7275487", "title": "Discrete manufacturing", "text": "Discrete manufacturing is the production of distinct items. Automobiles, furniture, toys, smartphones, and aeroplanes are examples of discrete manufacturing products. The resulting products are easily identifiable and differ greatly from process manufacturing where the products are undifferentiated, for example oil, natural gas and salt.\nDiscrete manufacturing is often characterized by individual or separate unit production. Units can be produced in low volume with very high complexity or high volumes of low complexity. Low volume/high complexity production results in the need for a flexible manufacturing system that can improve quality and time-to-market speed while cutting costs. High volume/low complexity production puts high premiums on inventory controls, lead times and reducing or limiting materials costs and waste.\nIndustry Profile - Discrete Manufacturing includes makers of consumer electronics, computer and accessories, appliances, and other household items, as well as \"big ticket” consumer and commercial goods like cars and aeroplanes. Discrete Manufacturing companies make physical products that go directly to businesses and consumers, and assemblies that are used by other manufacturers. \nThe processes deployed in discrete manufacturing are not continuous in nature. Each process can be individually started or stopped and can be run at varying production rates. The final product may be produced out of single or multiple inputs. Producing a steel structure will need only one type of raw material - steel. Producing a mobile phone requires many different inputs. The plastic case, LCD display, the mainboard, PVC keypad, sockets, cables are made from different materials, at different places. This is different from Process manufacturing like production of paper or petroleum refining, where the end product is obtained by a continuous process or a set of continuous processes.\nProduction capacity of the factory as a whole in discrete manufacturing is impossible to calculate. It is the question of common sense that how can one calculate the production capacity of its multiple characterize different products because the production time and machine setups of the parts produced are different from each other.", "Engineering,_Manufacturing": 0.9999815226, "qwen": "Yes"}
{"id": "7666616", "revid": "1256358", "url": "https://en.wikipedia.org/wiki?curid=7666616", "title": "List of computer hardware manufacturers", "text": "Current notable computer hardware manufacturers:\nCases.\nList of computer case manufacturers:\nMotherboards.\nTop motherboard manufacturers:\nList of mainboard manufacturers:\n\"Defunct\":\nCentral processing units (CPUs).\nNote: most of these companies only make designs, and do not manufacture their own designs. \nTop x86 CPU manufacturers:\nList of CPU manufacturers (most of the companies sell ARM-based CPUs, assumed if nothing else stated):\nHard disk drives (HDDs).\nInternal.\nList of current hard disk drive manufacturers:\nExternal.\nNote: the HDDs internal to these devices are manufactured only by the internal HDD manufacturers listed above.\nList of external hard disk drive manufacturers:\nSolid-state drives (SSDs).\nMany companies manufacture SSDs but only six companies actually manufacture the NAND flash devices that are the storage element in most SSDs.\nOptical disc drives (ODDs).\nList of optical disc drive manufacturers:\nComputer cooling systems.\nList of computer cooling system manufacturers:\nNon-refillable liquid cooling (AiO).\nList of non-refillable liquid cooling manufacturers:\nRefillable liquid cooling kits.\nList of refillable liquid cooling kits manufacturers:\nWater block.\nList of water block manufacturers:\nVideo-card cooling.\nList of graphics card cooling manufacturers:\nComputer monitors.\nList of companies that are actively manufacturing and selling computer monitors:\nVideo cards (graphics cards).\nList of video card manufacturers:\nKeyboards.\nList of keyboard manufacturers:\nMouse.\nList of mouse manufacturers:\nMouse pads.\nList of mouse pad manufacturers:\nJoysticks.\nList of Joystick manufacturers:\nSpeakers.\nList of computer speaker manufacturers:\nModems.\nList of modem manufacturers:\nNetwork interface cards (NICs).\nList of network card manufacturers:\nChipsets for network cards.\nThere are a number of other companies (AMD, Microchip, Altera, etc) making specialized chipsets as part of other ICs, and they are not often found in PC hardware (laptop, desktop or server). There are also a number of now defunct companies (like 3com, DEC, SGI) that produced network related chipsets for us in general computers.\nPower supply units (PSUs).\nList of power supply unit (PSU) manufacturers:\nRandom-access memory (RAM) modules.\nNote that the actual memory chips are manufactured by a small number of DRAM manufacturers. List of memory module manufacturers:\nRandom-access memory (RAM) chips.\nList of current DRAM manufacturers:\nList of former or defunct DRAM manufacturers:\nList of fabless DRAM companies:\nIn addition, other semiconductor manufacturers include SRAM or eDRAM embedded in larger chips.\nHeadphones.\nList of headphone manufacturers:\nImage scanners.\nList of image scanner manufacturers:\nSound cards.\nList of sound card manufacturers:\nTV tuner cards.\nList of TV tuner card manufacturers:\nUSB flash drives.\nList of USB flash drive manufacturers:\nWebcams.\nList of webcam manufacturers:\nGaming chair.\nList of gaming chair manufacturers:", "Engineering,_Manufacturing": 0.9997586608, "qwen": "Yes"}
{"id": "758730", "revid": "27799040", "url": "https://en.wikipedia.org/wiki?curid=758730", "title": "Electron-beam technology", "text": "Since the mid-20th century, electron-beam technology has provided the basis for a variety of novel and specialized applications in semiconductor manufacturing, microelectromechanical systems, nanoelectromechanical systems, and microscopy.\nMechanism.\nFree electrons in a vacuum can be manipulated by electric and magnetic fields to form a fine beam. Where the beam collides with solid-state matter, electrons are converted into heat or kinetic energy. This concentration of energy in a small volume of matter can be precisely controlled electronically, which brings many advantages.\nApplications.\nThe rapid increase of temperature at the location of impact can quickly melt a target material. In extreme working conditions, the rapid temperature increase can even lead to evaporation, making an electron beam an excellent tool in heating applications, such as welding. Electron beam technology is used in cable-isolation treatment, in electron lithography of sub-micrometer and nano-dimensional images, in microelectronics for electron-beam curing of color printing and for the fabrication and modification of polymers, including liquid-crystal films, among many other applications.\nFurnaces.\nIn a vacuum, the electron beam provides a source of heat that can melt or modify any material. This source of heat or phase transformation is absolutely sterile due to the vacuum and scull of solidified metal around the cold copper crucible walls. This ensures that the purest materials can be produced and refined in electron-beam vacuum furnaces. Rare and refractory metals can be produced or refined in small-volume vacuum furnaces. For mass production of steels, large furnaces with capacity measured in metric tons and electron-beam power in megawatts exist in industrialized countries.\nWelding.\nSince the beginning of electron-beam welding on an industrial scale at the end of the 1950s, countless electron-beam welders have been designed and are being used worldwide. These welders feature working vacuum chambers ranging from a few liters up to hundreds of cubic meters, with electron guns carrying power of up to 100 kW.\nSurface treatments.\nModern electron-beam welders are usually designed with a computer-controlled deflection system that can traverse the beam rapidly and accurately over a selected area of the work piece. Thanks to the rapid heating, only a thin surface layer of the material is heated. Applications include hardening, annealing, tempering, texturing, and polishing (with argon gas present). If the electron beam is used to cut a shallow trough in the surface, repeatedly moving it horizontally along the trough at high speeds creates a small pile of ejected melted metal. With repetition, spike structures of up to a millimeter in height can be created. These structures can aid bonding between different materials and modify the surface roughness of the metal.\nAdditive manufacturing.\nAdditive manufacturing is the process of joining materials to make objects from 3D model data, usually by melting powder material layer upon layer. Melting in a vacuum by using a computer-controlled scanning electron beam is highly precise. Electron-beam direct manufacturing (DM) is the first commercially available, large-scale, fully programmable means of achieving near net shape parts.\nMetal powder production.\nThe source billet metal is melted by an electron beam while being spun vigorously. Powder is produced as the metal cools when flying off the metal bar.\nMachining.\nElectron-beam machining is a process in which high-velocity electrons are concentrated into a narrow beam with a very high planar power density. The beam cross-section is then focused and directed toward the work piece, creating heat and vaporizing the material. Electron-beam machining can be used to accurately cut or bore a wide variety of metals. The resulting surface finish is better and kerf width is narrower than what can be produced by other thermal cutting processes. However, due to high equipment costs, the use of this technology is limited to high-value products.\nLithography.\nAn electron lithograph is produced by a very finely focused electron beam, which creates micro-structures in the resist that can subsequently be transferred to the substrate material, often by etching. It was originally developed for manufacturing integrated circuits and is also used for creating nanotechnology architectures. Electron lithographs uses electron beams with diameters ranging from two nanometers up to hundreds of nanometers. The electron lithograph is also used to produce computer-generated holograms (CGH). Maskless electron lithography has found wide usage in photomask making for photolithography, low-volume production of semiconductor components, and research and development activities.\nPhysical-vapor-deposition solar-cell production.\nPhysical vapor deposition takes place in a vacuum and produces a thin film of solar cells by depositing thin layers of metals onto a backing structure. \nElectron-beam evaporation uses thermionics emission to create a stream of electrons that are accelerated by a high-voltage cathode and anode arrangement. Electrostatic and magnetic fields focus and direct the electrons to strike a target. The kinetic energy is transformed into thermal energy at or near the surface of the material. The resulting heating causes the material to melt and then evaporate. Temperatures in excess of 3500 degrees Celsius can be reached. The vapor from the source condenses onto a substrate, creating a thin film of high-purity material. Film thicknesses from a single atomic layer to many micrometers can be achieved. This technique is used in microelectronics, optics, and material research, and to produce solar cells and many other products.\nCuring and sterilization.\nElectron-beam curing is a method of curing paints and inks without the need for traditional solvent. Electron-beam curing produces a finish similar to that of traditional solvent-evaporation processes, but achieves that finish through a polymerization process. E-beam processing is also used to cross-link polymers to make them more resistant to thermal, mechanical or chemical stresses.\nE-beam processing has been used for the sterilization of medical products and aseptic packaging materials for foods, as well as disinfestation, the elimination of live insects from grain, tobacco, and other unprocessed bulk crops.\nElectron microscopes.\nAn electron microscope uses a controlled beam of electrons to illuminate a specimen and produce a magnified image. Two common types are the scanning electron microscope (SEM) and the transmission electron microscope (TEM).\nMedical Radiation Therapy.\nElectron beams impinging on metal produce X-rays. The X-rays may be diagnostic, e.g., dental or limb images. Often in these X-ray tubes the metal is a spinning disk so that it doesn't melt; the disk is spun in vacuum via a magnetic motor. The X-rays may also be used to kill cancerous tissue. The Therac-25 machine is an infamous example of this.", "Engineering,_Manufacturing": 1.0000071526, "qwen": "Yes"}
{"id": "28385525", "revid": "136926", "url": "https://en.wikipedia.org/wiki?curid=28385525", "title": "Spare part", "text": "A spare part, spare, service part, repair part, or replacement part, is an interchangeable part that is kept in an inventory and used for the repair or refurbishment of defective equipment/units. Spare parts are an important feature of logistics engineering and supply chain management, often comprising dedicated spare parts management systems.\nSpare parts are an outgrowth of the industrial development of interchangeable parts and mass production.\nIn an industrial environment, spare parts are described in several manner to distinguish key features of various spare parts. The following describes spare part types and their typically functionality.\n1. Capital parts are spare parts which, although acknowledged to have a long life or a small chance of failure, would cause a long shutdown of equipment because it would take a long time to get a replacement for them. Capital parts are typically repaired or replaced during planned overhauls/scheduled inspections.  As description implies, these Capital Parts are typically expensive and are depreciated over time.\nExamples of capital parts include pumps and motor sets used in industrial plants, or impeller or a rotor required for a pump or motor. This “spare” requirement would be determined by redundancy of equipment used in the industrial processes. \n2. Consumables can be divided into two groups:\n3. Inspection spares or outage spares typically refer to those spare parts used in conjunction with Capital Parts during planned overhauls/scheduled inspections and maybe reused but typically are not repairable and are discarded after removal from use if Inspection Spares are damaged. These Inspection Spares are sometimes mis-characterized as Capital spares (vs Capital Parts) and are also confounded with Inspection Consumables, which must be replaced at every inspection/outage.  (an example of inspection spares would be bearings and mechanical seals, large bolts and nuts.)\n4. Operational spares typically refer to those spare parts that are used during operation of equipment and would not require planned overhauls/scheduled inspections to replace. In an industrial setting, operational spares would be gages, valves (solenoid, MOVs that are in redundancy), transmitters, I/O boards, small AC/DC power supplies, etc.) (for a car, it would windshield wiper)\nClassification.\nIn logistics, spare parts can be broadly classified into two groups, repairables and consumables.\nEconomically, there is a tradeoff between the cost of ordering a replacement part and the cost of repairing a failed part. When the cost of repair becomes a significant percentage of the cost of replacement, it becomes economically favorable to simply order a replacement part. In such cases, the part is said to be \"beyond economic repair\" (BER), and the percentage associated with this threshold is known as the BER rate. Analysis of economic tradeoffs is formally evaluated using Level of Repair Analysis (LORA).\nRepairable.\nRepairable parts are parts that are deemed worthy of repair, usually by virtue of economic consideration of their repair cost. Rather than bear the cost of completely replacing a finished product, repairables typically are designed to enable more affordable maintenance by being more modular. That allows components to be more easily removed, repaired, and replaced, enabling cheaper replacement. Spare parts that are needed to support condemnation of repairable parts are known as \"replenishment\" spares .\nA rotable pool is a pool of repairable spare parts inventory set aside to allow for multiple repairs to be accomplished simultaneously, which can be used to minimize stockout conditions for repairable items.\nConsumable.\nParts that are not repairable are considered consumable parts. Consumable parts are usually scrapped, or \"condemned\", when they are found to have failed. Since no attempt at repair is made, for a fixed mean time between failures (MTBF), replacement rates for consumption of consumables are higher than an equivalent item treated as a repairable part. Therefore, consumables tend to be lower-cost items.\nBecause consumables are lower cost and higher volume, economies of scale can be found by ordering in large lot sizes, a so-called economic order quantity.\nLegislation.\nThere is no UK or EU legislation which states that spare parts have to be available for any set period of time, but some trade associations require their members to ensure products are not rendered useless because spare parts are not available. The 'six year rule' in the UK Sale of Goods Act 1979 relates to the time period for enforcing claims that goods where defective when sold, not to whether spare parts are available to repair them, and section 23(3) of the Consumer Rights Act 2015 states that a consumer cannot require a trader to repair or replace goods if \"the repair or replacement is impossible\", implying that if spare parts are no longer available the consumer's Right to Repair (or to have a spare part supplied) would be lost.\nRepair cycle.\nFrom the perspective of logistics, a model of the life cycle of parts in a supply chain can be developed. This model, called the repair cycle, consists of functioning parts in use by equipment operators, and the entire sequence of suppliers or repair providers that replenish functional part inventories, either by production or repair, when they have failed. Ultimately, this sequence ends with the manufacturer. This type of model allows demands on a supply system to ultimately be traced to their operational reliability, allowing for analysis of the dynamics of the supply system, in particular, spare parts.\nInventory management.\nCannibalization.\nWhen stockout conditions occur, cannibalization can result. This is the practice of removing parts or subsystems necessary for repair from another similar device, rather than from inventory. The source system is usually crippled as a result, if only temporarily, in order to allow the recipient device to function properly again. As a result, operational availability is impaired.\nCommercial.\nIndustrialization has seen the widespread growth of commercial manufacturing enterprises, such as the automotive industry, and later, the computer industry. The resulting complex systems have evolved modular support infrastructures, with the reliance on auto parts in the automotive industry, and replaceable computer modules known as field-replaceable units (FRUs).\nMilitary.\nMilitary operations are significantly affected by logistics operations. The system availability, also known as mission capable rate, of weapon systems and the ability to effect the repair of damaged equipment are significant contributors to the success of military operations. Systems that are in a mission-incapable (MICAP) status due lack of spare parts are said to be \"awaiting parts\" (AWP), also known as not mission capable due to supply (NMCS).\nBecause of this sensitivity to logistics, militaries have sought to make their logistics operations as effective as possible, focusing effort on operations research and optimal maintenance. Maintenance has been simplified by the introduction of interchangeable modules known as line-replaceable units (LRUs). LRUs make it possible to quickly replace an unserviceable (failed) part with a serviceable (working) replacement. This makes it relatively straightforward to repair complex military hardware, at the expense of having a ready supply of spare parts.\nThe cost of having serviceable parts available in inventory can be tremendous, as items that are prone to failure may be demanded frequently from inventory, requiring significant inventory levels to avoid depletion. For military programs, the cost of spare inventory can be a significant portion of acquisition cost.\nIn recent years, the United States Department of Defense (DoD) has advocated the use of performance-based logistics (PBL) contracts to manage costs for support of weapon systems.", "Engineering,_Manufacturing": 0.99999547, "qwen": "Yes"}
{"id": "28398469", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=28398469", "title": "White Family Rotary", "text": "The White Family Rotary or White FR, later White Rotary or White Rotary Electric, was the first rotary hook sewing machine produced by the White Sewing Machine Company, introduced circa 1900. It joined the successful White Vibrating Shuttle on White's expanding product line and eventually eclipsed it. It was originally sold as a treadle with cabinet or as a hand-crank with carrying case. Later, add-on electric motors with foot or knee control were available pre-installed or as a field upgrade. Typical cost for this machine as a treadle with a cabinet was US$65 in 1909, which is about US$1532 adjusted. \nThe White Rotary was sold under multiple brands, including Domestic, Franklin, and Kenmore. A White Rotary Electric Series 77 machine was placed in the Crypt of Civilization.\nWhite reused the White Rotary name in the 1950s and 1960s, applying it to a machine manufactured by Juki (White model #659). This machine had a rotary-driven thread takeup instead of the more common takeup lever. The Rotary name was later used again on a stretch stitch-capable sewing machine.", "Engineering,_Manufacturing": 0.9998109937, "qwen": "Yes"}
{"id": "28423194", "revid": "44230401", "url": "https://en.wikipedia.org/wiki?curid=28423194", "title": "Russel Metals", "text": "Russel Metals Inc. is a Canadian metals distribution and processing company. It is one of North America's largest metal distribution companies, with operations across Canada and the United States.\nHistory.\nThe company was originally established in 1929 as Federal Grain Limited, through a merger of several grain-handling firms. In 1972, the company sold its grain assets to several grain pools, and it then renamed itself as Federal Industries Ltd. \nAfter 1978, under the leadership of CEO John Fraser, the company expanded into a diverse range of industries, including bookstores, trucking and airplane parts. One of the businesses acquired was metals firm Hugh Russel & Sons Ltd., which had originally been founded in 1785 as John Russel & Co. in Montreal by Scottish-born merchant John Russel. The company also acquired the narrow-gauge Yukon and White Pass Railroad, which shipped freight between Whitehorse, Yukon, and Skagway, Alaska (eventually sold in 1997).\nThe company's expansion into diverse business lines was not successful, and it experienced significant losses during a recession in the 1990s. As a result, it sold off many of its non-core assets to focus on metals distribution and processing. As part of this process, the company renamed itself as Russel Metals Inc. in 1995. After a 1997 proxy battle involving businessman K. Rai Sahi, John Fraser and CEO John Pelton resigned, and the company narrowed its focus on metals under new CEO Bud Siegal.\nIn 2007, Russel acquired JMS Metal Products, a U.S. metals distributor, for $125 million. In 2009, the company experienced significant losses as part of the great recession and laid off 500 of its 3,000 employees. In 2012, the company acquired Apex Distribution, a Calgary-based metals distribution business focusing on the oil and gas industry.\nBusiness.\nRussel Metals primarily operates metal distribution and service centres for customers in the oil and gas, manufacturing, and construction industries. It has three business segments: metals service centres, energy products, and steel distributors. As of 2017, 49% of revenue was from the service centres, 39% was from energy products, and the rest was from steel distribution. It has sites in both Canada and the United States, with most sites located in Canada, and derives roughly 30 per cent of its revenues from the United States.", "Engineering,_Manufacturing": 0.9985874891, "qwen": "Yes"}
{"id": "44455145", "revid": "43051325", "url": "https://en.wikipedia.org/wiki?curid=44455145", "title": "Automation engineering", "text": "Automation engineering is the provision of automated solutions to physical activities and industries.\nAutomation engineer.\nAutomation engineers are experts who have the knowledge and ability to design, create, develop and manage machines and systems, for example, factory automation, process automation and warehouse automation.\nAutomation technicians are also involved.\nScope.\nAutomation engineering is the integration of standard engineering fields. Automatic control of various control systems for operating various systems or machines to reduce human efforts & time to increase accuracy. Automation engineers design and service electromechanical devices and systems to high-speed robotics and programmable logic controllers (PLCs).\nWork and career after graduation.\nGraduates can work for both government and private sector entities such as industrial production, \ncompanies that create and use automation systems, for example paper industry, automotive industry, food and agricultural industry, water treatment, and oil & gas sector such as refineries, power plants.\nJob Description.\nAutomation engineers can design, program, simulate and test automated machinery and processes, and usually are employed in industries such as the energy sector in plants, car manufacturing facilities or food processing plants and robots. Automation engineers are responsible for creating detailed design specifications and other documents, developing automation based on specific requirements for the process involved, and conforming to international standards like IEC-61508, local standards, and other process specific guidelines and specifications, simulate, test and commission electronic equipment for automation.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "44467079", "revid": "20838146", "url": "https://en.wikipedia.org/wiki?curid=44467079", "title": "Production planning", "text": " \nProduction planning is the planning of production and manufacturing modules in a company or industry. It utilizes the resource allocation of activities of employees, materials and production capacity, in order to serve different customers.\nDifferent types of production methods, such as single item manufacturing, batch production, mass production, continuous production etc. have their own type of production planning. Production planning can be combined with production control into production planning and control, or it can be combined with enterprise resource planning.\nOverview.\nProduction planning is the future of production. It can help in efficient manufacturing or setting up of a production site by facilitating required needs. A production plan is made periodically for a specific time period, called the planning horizon. It can comprise the following activities:\nIn order to develop production plans, the production planner or production planning department needs to work closely together with the marketing department and sales department. They can provide sales forecasts, or a listing of customer orders.\" The \"work is usually selected from a variety of product types which may require different resources and serve different customers. Therefore, the selection must optimize customer-independent performance measures such as cycle time and customer-dependent performance measures such as on-time delivery.\"\nA critical factor in production planning is \"the accurate estimation of the productive capacity of available resources, yet this is one of the most difficult tasks to perform well\". Production planning should always take \"into account material availability, resource availability and knowledge of future demand\".\nHistory.\nModern production planning methods and tools have been developed since late 19th century. Under Scientific Management, the work for each man or each machine is mapped out in advance (see image). The origin of production planning back goes another century. Kaplan (1986) summarized that \"the demand for information for internal planning and control apparently arose in the first half of the 19th century when firms, such as textile mills and railroads, had to devise internal administrative procedures to coordinate the multiple processes involved in the performance of the basic activity (the conversion of raw materials into finished goods by textile mills, the transportation of passengers and freight by the railroads.\"\nHerrmann (1996) further describes the circumstances in which new methods for internal planning and control evolved: \"The first factories were quite simple and relatively small. They produced a small number of products in large batches. Productivity gains came from using interchangeable parts to eliminate time-consuming fitting operations. Through the late 1800s, manufacturing firms were concerned with maximizing the productivity of the expensive equipment in the factory. Keeping utilization high was an important objective. Foremen ruled their shops, coordinating all of the activities needed for the limited number of products for which they were responsible. They hired operators, purchased materials, managed production, and delivered the product. They were experts with superior technical skills, and they (not a separate staff of clerks) planned production. Even as factories grew, they were just bigger, not more complex.\nAbout production planning Herrmann (1996) recounts that \"production scheduling started simply also. Schedules, when used at all, listed only when work on an order should begin or when the order is due. They didn't provide any information about how long the total order should take or about the time required for individual operations ...\"\nIn 1923 \"Industrial Management\" cited a Mr. Owens who had observed: \"Production planning is rapidly becoming one of the most vital necessities of management. It is true that every establishment, no matter how large or how small has production planning in some form; but a large percentage of these do not have planning that makes for an even flow of material, and a minimum amount of money tied up in inventories.\"\nTopics.\nTypes of planning.\nDifferent types of production planning can be applied:\nRelated kind of planning in organizations\nProduction control.\nProduction control is the activity of controlling the workflow in the production. It is partly complementary to production planning.", "Engineering,_Manufacturing": 0.9999859333, "qwen": "Yes"}
{"id": "42491069", "revid": "38655588", "url": "https://en.wikipedia.org/wiki?curid=42491069", "title": "Systematic Automation", "text": "Systematic Automation, Inc. is the world's largest manufacturer of precision screen printing machines, vacuum tables, rotary indexer base machines, and UV curing devices. The company, located in Farmington, CT, specializes in standard and custom solutions for a variety of screen printing applications. Though originally a manufacturer of screen printing machines, the company has expanded its operations to include vacuum tables and UV curing devices.\nHistory.\nSystematic Automation, Inc. was founded in 1983 in Chicago, Illinois. The company moved to a larger facility in Connecticut to accommodate a doubling of capacity in 1987. Systematic Automation invented a rotary indexing table in 1988, introducing the technology to screen printing applications. That same year, the company entered the UV curing industry with the introduction of the UVSP Curing Unit. To meet the complex requirements of multicolor screen printed designs, a new line of machines was designed and manufactured in 2001 that consisted of a conveying system for multiple vacuum tables moved successively through screen printing and UV curing work stations. More recently, engineers at the company have developed machines for automatically printing insulated foam can coolers, known as koozies, as well as a fully automatic screen printer for microscope slides or other flat glass. Other notable accomplishments include building a screen printing machine capable of depositing 0.002\" lines of platinum 0.002\" apart for hydrogen battery wafers used on the Space Shuttle.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "1024008", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1024008", "title": "Homebuilt machines", "text": "Homebuilt machines are machines built outside of specialised workshops or factories. This can include different things such as kit cars or homebuilt computers, but normally it pertains to homebuilt aircraft, also known as amateur-built aircraft or kit planes. Homebuilt aircraft or kit cars are constructed by amateurs. Homebuilt computers have been built at home for a long time, starting with the Victorian era pioneer Charles Babbage in the 1820s. A century later, Konrad Zuse built his own machine when electromechanical relay technology was widely available. The hobby took off with the early development of microprocessors and, since then, many enthusiasts have constructed their own computers.\nA homebuilt vehicle is a wider concept than a kit car. A homebuilt vehicle is a motor vehicle (car, truck or motorcycle) built by an individual instead of a manufacturer.\nThese machines may be constructed \"from scratch\", from plans, or from assembly kits. Outside of the United States (for example in Russia) people wishing to build such complex machinery often have no professional networks to rely on for spare parts, plans, or advice in the matter and therefore have to rely on their ingenuity and intuition in order to build a machine that works.", "Engineering,_Manufacturing": 1.0000054836, "qwen": "Yes"}
{"id": "2301590", "revid": "34412543", "url": "https://en.wikipedia.org/wiki?curid=2301590", "title": "NC-CAM", "text": "NC-CAM is a computer-aided manufacturing software program introduced in 1989, and used by printed circuit board manufacturers to create, modify, and optimize the CNC program files used by printed circuit board drilling and routing machines. In particular, NC-CAM is used to optimize the RS-274C Excellon format files used to program Excellon, Hitachi and other printed circuit board drilling and routing machines.\nNC-CAM was first developed for MS-DOS by Robert Henningsgard, and it is today developed and supplied for Microsoft Windows by FASTechnologies, Corp. of Big Lake, Minnesota, USA.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "2309345", "revid": "76", "url": "https://en.wikipedia.org/wiki?curid=2309345", "title": "Vacuum casting (elastomers)", "text": "Vacuum casting is a casting process for elastomers using a vacuum to draw the liquid material into the mold. This process is used when air entrapment is a problem, there are intricate details or undercuts, or if the material is fiber or wire reinforced.\nThe main disadvantage to this process is the high price for the equipment.\nProcess.\nThe process starts by placing a two piece silicone mold in a vacuum chamber. The raw material is mixed, degassed and then poured into the mold. The vacuum is then released and the mold removed from the chamber. Finally, the casting is cured in an oven and the mold removed to release the completed casting. The silicone mold can be reused.\nIn some machines the chamber where the material is mixed a pressure can be applied to increase the pressure differential between the mold cavity and the mixing chamber.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "42071443", "revid": "43783383", "url": "https://en.wikipedia.org/wiki?curid=42071443", "title": "Shot peening of steel belts", "text": "Shot peening can be used to recondition distorted steel conveyor belts. The shot peening process is quick and cost-effective compared with other methods and does not interrupt daily production. A deformed steel belt has the following disadvantages:\nThe shot peening process.\nShot peening is a maintenance process for flattening a deformed steel belt in which the surface of the belt is impacted by small spherical stainless steel or carbon steel balls called peening shot. Each shot hitting the belt functions as a small peening hammer, forming a small indentation or dimple on the steel belt surface. In order for the indentation to be formed, the steel belt surface layer must yield in tension. The compressed grains help to restore the surface to its original shape by producing a hemisphere of cold-worked metal highly stressed in compression. Overlapping indentations create a continuous layer of residual compressive stress. It is well known that cracks will not lead up nor propagate in a compressive stressed zone. Because nearly all fatigue and stress corrosion failures originate at the surface of a part, compressive stresses generate by shot peening provide very important increases in life time. Note that:\nPortable shot blasting unit.\nThe main use of the unit is to flatten out deformed press belts whilst simultaneously stress-relieving the belt material. The small size and low weight makes the unit flexible to use and easy to bring into and operate in field situations. All of the equipment needed (excluding the carriage frame and the air compressor) can be packed into a box with dimensions of about: 350mm L × 350mm W × 320 mm. Total weight including blaster, valve, air hose and miscellaneous components is around 25 kg and the blasting machine itself weights only 9 kg. One pair of universal channel (38 mm * 76 mm) must be provided on site – the length usually being 500 mm longer than the belt width. The channels are welded together so that the blaster can easily run through the frame across the face of the belt. The total installation time, including the manufacture of the carriage frame, is limited to just a few hours after which the peening process can begin. On the inlet air hose an electric shut-off valve is mounted to protect the belt from over-blasting should the belt suddenly stop during the blasting operation. To be effective the valve solenoid must be connected / interlocked to the press machine's power supply (240 V). For best blasting results an air supply of 4200 litres per minute is required at a pressure of 6 bar. A flexible air hose is supplied with the unit which is to be connected between the blasting unit and the local air supply. All local supply pipes should have a minimum bore diameter of 1 inch. The recommended shot blasting medium is tungsten shot (beads) with diameter ranging from 0.2 to 0.4 mm having a hardness exceeding 40 HRC. The machine operates by drawing a quantity of tungsten shot from the bottom of the scroll case into the high-velocity nozzles. The shot is blasted onto the surface of the belt, and most of the shot bounces back into the scroll case. The air is vented through the filter socks, and any shot carried with the air is filtered out and drops back into the scroll case.\nFlattening out deformed belts.\nHistorically (per 1980s), the common method previously used to solve the problem of deformed belts was to turn the belt over i.e. what was previously the back of the belt is then used to form the new product side. The belt became flatter being turned because of an equalization of the stresses on the two sides.\nHowever, the belt usually continues to change its shape so that it eventually acquires the same shape as before being turned but in the opposite direction. \nBecause of this, turning the belt again after a period of approximately one year was often necessary. This method is very time-consuming and thus very costly since it involves cutting the belt, dismantling it from the press, turning the belt and re-installing it in the press followed by the belt joining operations (welding and grinding of the joint) and running-in procedures. All these operations also require equipment for handling the belt as well as special welding jigs and skilled personnel for the joint-welding. Added to this is the loss of production during the operation – a stoppage in production of one week being not uncommon. The steel belt shot peening process was developed as a superior solution to the Belt cross curvature problem.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "11306915", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=11306915", "title": "Pickering Interfaces", "text": "Pickering Interfaces is a test and measurement company headquartered in Clacton-on-Sea, United Kingdom. Pickering designs, manufactures and markets a range of switching, simulation and cabling products in the LXI, PXI, and PCI platforms. These products are sold into the functional test, hardware-in-the-loop simulation (HILS) and design verifications markets.\nPickering is a privately owned company with design and manufacturing facilities in Clacton-on-Sea, UK and Trinec in the Czech Republic, together with additional company operated direct sales and support operations in the US, Germany, France, Sweden and China.\nPrincipal product range.\nPickering's primary products are in the PXI, LXI, USB and PCI platforms, specifically in switching, programmable resistors, attenuators, power supplies, basic instrumentation, software and cabling for these products.", "Engineering,_Manufacturing": 0.999769628, "qwen": "Yes"}
{"id": "2817302", "revid": "1122309140", "url": "https://en.wikipedia.org/wiki?curid=2817302", "title": "Methods of production", "text": "Production methods fall into three main categories: job (one-off production), batch (multiple items, one step at a time for all items), and flow\nJob production.\nJob production is used when a product is produced with the labor of one or few workers and is rarely used for bulk and large scale production. It is mainly used for one-off products or prototypes (hence also known as \"Prototype Production\"), as it is inefficient; however, quality is greatly enhanced with job production compared to other methods. Individual wedding cakes and made-to-measure suits are examples of job production. New small firms often use job production before they get a chance or have the means to expand. Job Production is highly motivating for workers because it gives the workers an opportunity to produce the whole product and take pride in it.\nBatch production.\nBatch production is the method used to produce or process any product of the groups or batches where the products in the batch go through the whole production process together. An example would be when a bakery produces each different type of bread separately and each product (in this case, bread) is not produced continuously. Batch production is used in many different ways and is most suited to when there is a need for a quality/quantity balance. This technique is probably the most commonly used method for organizing manufacture and promotes specialist labor, as very often batch production involves a small number of persons. Batch production occurs when many similar items are produced together. Each batch goes through one stage of the production before moving onto the next stage.\nFlow production.\nFlow production (mass production) is also a very common method of production. Flow production is when the product is built up through many segregated stages; the product is built upon at each stage and then passed directly to the next stage where it is built upon again. The production method is financially the most efficient and effective because there is less of a need for skilled workers.\nLean Production.\nContrary to job production, the method Boutique Manufacturing (Lean) is suitable for the production of very small to small batches, i.e. orders of a few units up to several dozens of similar or equal goods. The workflow organization of a Boutique Manufacturing entity can be a mixture of both jobbing and batch production but involves higher standardization than job production. Boutique Manufacturing is often organized with single workplaces or production cells carrying out a number of subsequent production steps until completion of certain components or even the whole product; large assembly lines are generally not used. The flexibility and variety of products able to be produced in the entity therefore are much higher than with the more standardized method of batch production.", "Engineering,_Manufacturing": 0.999899745, "qwen": "Yes"}
{"id": "2817899", "revid": "46362847", "url": "https://en.wikipedia.org/wiki?curid=2817899", "title": "KCC Corporation", "text": "KCC Corporation (renamed from Kumkang Korea Chemicals Co., Ltd. on February 25, 2005) is a Korean chemical and auto parts manufacturer, headquartered in Seoul, South Korea.\nOperations.\nKCC's products include various kinds of paints, float glass, soft sponges, silicon, chassis, and car parts. This company is the biggest provider of construction materials and paints in South Korea. Various types of industrial materials such as epoxy moulding compound, alumina metallizing, silicone etc. are produced in 13 domestic locations.\nKCC Corporation has 9 overseas liaison offices and 7 overseas factories over the world:\nMain Rivals in Silicone Markets.\nKCC's silicone is one of major market which is developing. There are some main rivals for this Korean company to develop market as the list below:\nPurchasing Basildon Chemical.\nApril 2011, Basildon Chemicals was purchased by the KCC Corporation of Korea. In this partnership, KCC gains a company with a history in silicone emulsification.", "Engineering,_Manufacturing": 0.9898750186, "qwen": "Yes"}
{"id": "27351235", "revid": "26426023", "url": "https://en.wikipedia.org/wiki?curid=27351235", "title": "Stamped circuit board", "text": "A stamped circuit board (SCB) is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or traces etched from copper sheets laminated onto a non-conductive \"substrate\". This technology is used for small circuits, for instance in the production of LEDs.\nSimilar to printed circuit boards this layer structure may comprise glass-fibre reinforced epoxy resin and copper. Basically, in the case of LED substrates three variations are possible: \nUsing the SCB technology it is possible to structure and laminate the most widely differing material combinations in a reel-to-reel production process. As the layers are structured separately, improved design concepts are able to be implemented. Consequently, a far better and quicker heat dissipation from within the chip is achieved.\nProduction.\nBoth the plastic and the metal are initially processed on separate reels, .i.e. in accordance with the requirements the materials are individually structured by stamping (“brought into form“) and then merged.\nAdvantages.\nThe engineering respectively choice of substrates actually comes down to the particular application, module design/substrate assembly, material and thickness of the material involved.\nTaking these parameters it is possible to attain a good thermal management by using SCB technology, because rapid heat dissipation from beneath the chip means a longer service life for the system. Furthermore, SCB technology allows the material to be chosen to correspond to the pertinent requirements and then to optimize the design to arrive at a “perfect fit”.", "Engineering,_Manufacturing": 1.0000077486, "qwen": "Yes"}
{"id": "27355554", "revid": "37317555", "url": "https://en.wikipedia.org/wiki?curid=27355554", "title": "Scotland Manufacturing", "text": "Scotland Manufacturing, Inc. is a full-service stamping company and manufacturer of deep drawn metal stampings, progressive stamping (die manufacturing) and value-added assembly solutions. Scotland has presses running from 110 to 1,000 tons and the company provides refrigerant, compressor housing, filter shells and other deep-drawn stampings from the industrial, automotive and heavy truck industries.\nScotland Manufacturing is ISO 9001 certified and produces stampings from a variety of metals including cold rolled steel, electro tin plate and stainless steel. Their facility has more than of manufacturing space.\nHistory.\nScotland Manufacturing, located in Laurinburg, North Carolina, was founded in 1979 as a supplier to the filter industry. Named for Scotland County located in Southeastern North Carolina, the company is situated between Charlotte, the state’s largest city and Wilmington, the state’s largest port. From an $8-million business in 2001, Scotland Manufacturing has grown to a $20-million business in 2009.\nScotland Manufacturing is part of The Reserve Group (TRG), a private equity group based in Akron, Ohio. The Reserve Group’s philosophy is to provide strategic business support and investment capital, allowing its portfolio of companies to remain competitive in the marketplace. Scotland Manufacturing is the oldest member company in the TRG portfolio.\nProducts.\nFor the automotive industry, Scotland Manufacturing creates door panels for the high-end automotive OEM, clutch plates, transmission plates, brackets and filter cans. Additionally, the company uses a variety of metals, from flat steel to stainless steel, to produce components for the construction industry such as chimney caps, and brackets and braces for pre-fabricated buildings. Scotland also creates railway brake intercasings, rail shoes, rail pads and rail friction products as well as fire extinguishers and other components for the aerospace industry.\nScotland Manufacturing offers shell supply in either low cost cold rolled steel or stronger, more corrosion-resistant tin plate steel. Deep drawn stampings are manufactured in diameters from 2 5/8 inches to 5 inches wide and up to 12 inches tall. The company’s production capacity offers low, medium and high volume capabilities on presses ranging from 110 to 1,000 tons. Stampings are manufactured in steel, stainless steel, pre-coated steel and aluminum.\nScotland Manufacturing products are used to create filters, Mack trucks, John Deere Tractors, Dodge pick-up trucks, chimney caps, fire extinguishers, railroad car brakes, end caps and retainer plates. The production facility offers welding, assembly, and pressure testing.\nAssociations.\nScotland Manufacturing is a member of the following associations: Filter Manufacturers Council and American Filtration & Separations Society.\nIn addition, Scotland Manufacturing has partnered with Richmond Community College of Hamlet, North Carolina for an Industrial Training Program.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "27369936", "revid": "1131264885", "url": "https://en.wikipedia.org/wiki?curid=27369936", "title": "Fusion welding", "text": "Fusion welding is a generic term for welding processes that rely on melting to join materials of similar compositions and melting points. Due to the high-temperature phase transitions inherent to these processes, a heat-affected zone is created in the material (although some techniques, like beam welding, often minimize this effect by introducing comparatively little heat into the workpiece).\nIn contrast to fusion welding, solid-state welding does not involve the melting of materials.\nApplications.\nFusion welding has been a critical factor in the creation of modern civilization due to its vital role in construction practices. Besides bolts and rivets, there are no other practical methods for joining pieces of metal securely. Fusion welding is used in the manufacture of many everyday items, including airplanes, cars, and structures. \nBeyond construction, a large community uses both arc and flame contact welding to create artwork.\nTypes.\nElectrical.\nArc.\nArc welding is one of the many types of fusion welding. Arc welding joins two pieces of metal together by using an intermediate filler metal. The way this works is by completing an electrical circuit to create an electrical arc. This electrical arc is 6500 °F (3593 °C) in its center. This electrical arc is created at the tip of the filler metal. As the arc melts the metal, it is moved either by a person or a machine along the gap in the metals, creating a bond. This method is very common as it is typically done with a hand held machine. Arc welding machines are portable and can be brought onto job sites and hard to reach areas. It is also the most common method of underwater welding. Electrical arcs form between points separated by a gas. In the process of underwater welding a bubble of gas is blown around the area being welded so that an electrical arc may form. Underwater welding has many applications. Ship hulls are repaired and oil rigs are maintained with underwater arc welding.\nResistance welding is done using two electrodes. Each comes into contact with one of the pieces being welded. The two pieces of metal are then pressed together between the electrodes and an electric current is run through them. The pieces of metal begin to heat up at the point where they come into contact. The current is passed through the metal until it is hot enough that the two pieces melt and conjoin. As the metal cools the bond is solidified. This process requires large amounts of electricity. In most cases transformers are needed to provide enough amps. Resistance welding is a very prevalent form of fusion welding. It is used in the manufacturing of automobiles and construction equipment.\nLaser beam.\nConduction welding, also known as laser beam welding or radiation welding, is a highly precise form of fusion welding. \"Laser\" is an acronym for Light Amplification by Stimulated Emission of Radiation. The laser emits light in bursts called pumps. These bursts are aimed at the seam of the metals desired to be conjoined. As the laser bursts it is guided along the seam. These intense bursts melt the metal. The two metals when melted mix with each other. Once it has cooled the seam created is a strong bond. Lasers are efficient because they can be configured to make multiple welds at once. The laser beam can be split and sent to multiple locations greatly reducing the cost and amount of energy required. Laser beam welding finds applications in the automotive industry.\nInduction.\nInduction welding is a form of resistance welding. However, there are no points of contact between the metal being welding and the electrical source or the welder. In induction welding a coil is wrapped around a cylinder. This coil causes a magnetic field across the surface of the metal inside. This magnetic field flows in the opposite direction of the magnetic field on the inside of the cylinder. These magnetic flows impede each other. This heats the metal and causes the edges to melt together.\nChemical.\nOxyfuel.\nFlame contact is a very common form of welding. The most popular kind of flame contact welding is oxyfuel gas welding. Flame contact welding uses a flame exposed to the surface of the metals being welded to melt and then join them together. Oxyfuel uses oxygen as a primary ignition source in tandem with another gas such as acetylene to produce a flame which is 2500 °C at the tip and 2800-3500 °C at the tip of the inner cone. Other gasses such as propane and methanol can be used for oxyfuel welding. Acetylene is the most common gas used in oxyfuel welding.\nSolid reactant.\nSolid reactant welding uses reactions between elements and compounds. Certain compounds when mixed create an exothermic chemical reaction, meaning they give off heat. A very common reaction uses thermite, a combination of a metal oxide (rust) and aluminum. This reaction produces heat over 4000 °F. Solid reactant compounds are channeled to the two pieces of metal being joined. Once in place, a catalyst is used to start the reaction. This catalyst can be a chemical or another heat source. The heat created melts the metals being joined. Once it cools, a bond is formed. From welding together train tracks to entering bank vaults, solid reactant welding has many niche uses.", "Engineering,_Manufacturing": 1.0000064373, "qwen": "Yes"}
{"id": "27370341", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=27370341", "title": "Friction stir processing", "text": "Friction stir processing (FSP) is a method of changing the properties of a metal through intense, localized plastic deformation. This deformation is produced by forcibly inserting a non-consumable tool into the workpiece, and revolving the tool in a stirring motion as it is pushed laterally through the workpiece. The precursor of this technique, friction stir welding, is used to join multiple pieces of metal without creating the heat affected zone typical of fusion welding.\nWhen ideally implemented, this process mixes the material without changing the phase (by melting or otherwise) and creates a microstructure with fine, equiaxed grains. This homogeneous grain structure, separated by high-angle boundaries, allows some aluminium alloys to take on superplastic properties. Friction stir processing also enhances the tensile strength and fatigue strength of the metal. In tests with actively cooled magnesium-alloy workpieces, the microhardness was almost tripled in the area of the friction stir processed seam (to 120–130 Vickers hardness).\nProcess.\nIn friction stir processing (FSP), a rotating tool is used with a pin and a shoulder to a single piece of material to make specific property enhancement, such as improving the material's toughness or flexibility, in a specific area in the micro-structure of the material via fine grain of a second material with properties that improve the first.(Ma) Friction between the tool and workpieces results in localized heating that softens and plasticizes the workpiece. A volume of processed material is produced by movement of materials from the front of the pin to the back of the pin. During this process, the material undergoes intense plastic deformation and this results in significant grain refinement. (Mishra) FSP changes physical properties without changing physical state which helps engineers create things such as “high-strain-rate superplasticity”. The grain refinement occurs on the base material improving properties of the first material, while mixing with the second material. This allows for a variety of materials to be altered to be changed for things that may require other difficult to acquire conditions. The processes branches off of friction stir welding (FSW) which uses the same process to weld two pieces of different materials together without heating, melting, or having to change the materials' physical state.\nTool.\nThe tool has a crucial part to creation of the final product. The tool consists of two main functions: \nThe tool at its most simplest form consist of a shoulder, a small cylinder with a diameter of 50 mm, and a pin, a small threaded cylinder similar to a drill. The tool itself has been modified to reduce displaced volume of the metals as they merged. Recently two new pin geometries have arisen:\nApplications.\nThe FSP is used when metals properties want to be improved using other metals for support and improvement of the first. This is promising process for the automotive and aerospace industries where new material will need to be developed to improve resistance to wear, creep, and fatigue. (Misha) Examples of materials successfully processed using the friction stir technique include AA 2519, AA 5083 and AA 7075 aluminum alloys, AZ61 magnesium alloy, nickel-aluminium bronze and 304L stainless steel.\nCasting.\nMetallic parts produced by casting are comparatively inexpensive, but are often subject to metallurgical flaws like porosity and microstructural defects. Friction stir processing can be used to introduce a wrought microstructure into a cast component and eliminate many of the defects. By vigorously stirring a cast metal part to homogenize it and reduce the grain size, the ductility and strength are increased.\nPowder metallurgy.\nFriction stir processing can also be used to improve the microstructural properties of powder metal objects. In particular, when dealing with aluminium powder metal alloys, the aluminium oxide film on the surface of each granule is detrimental to the ductility, fatigue properties and fracture toughness of the workpiece. While conventional techniques for removing this film include forging and extrusion, friction stir processing is suited for situations where localized treatment is desired.\nFabrication of metal matrix composites.\nFSP can also be used to fabricate metal matrix composites at the nugget zone where we need the change of properties. Al 5052/SiC and some other composites were successfully fabricated. Even nano composites can also be fabricated by FSP.\nAluminium Surface Composites with Superior Properties.\nAluminium surface composites with enhanced surface properties can be fabricated using FSP. Aluminium surface composites fabricated with the optimum friction stir processing parameters show better mechanical properties and corrosion resistance. The processing parameters such as tool rotational speed and tool shoulder diameter affects the surface properties. Higher surface hardness is exhibited by the surface composites fabricated at higher tool rotational speed and lower tool shoulder diameter. The properties of the composite materials can be altered by changing the type of reinforcement. Reinforcement particles aids in the grain size refinement as well as the property enhancement in the processed materials. The surface composite properties can be varied by changing the reinforcement particles based on the end application. The reinforcement phases can be metallic, ceramic, or polymer materials. \nTesting.\nMg based nano-composites.\nFSP was used to modify a Mg alloy and insert nano-sized SiO2. The test was conducted a total four times with the average grain size varying from 0.5–2μm. This nearly doubled the hardness of the Mg and also increased the super-plasticity. At room temperature, the yield stress of the FSP composites was improved in the 1D and in the 2D specimens signifying a larger resistance of the product metal under high stress conditions without deforming. The tensile strength was shown to increase along with the yield stress.\nBenefits.\nFSP has benefits for when two materials' would be needed to be mixed. “FSP is a short route, solid state processing technique with one-step processing that achieves microstructural refinement densification and homogeneity” (Ma) FSW helps modify materials so that metaling down or changing the material drastically does not have to take place. FSP, for example, can easily change the form of a piece of material as sheets of metal, where before it may have had to be melted down before and put into a mold for it to cool and form. (Smith, Mishra) “The microstructure and mechanical properties of the processed zone can be accurately controlled by optimizing the tool design, FSP parameters an active cooling/heating.” (Ma) The same sheet of metal can be modified to fit various situations with the proper modification of the tool. FSP has shown to make metallic alloys bendable as for example an alloy modified with FSP would be able to bend to 30 degrees as before it could only bend to seven.", "Engineering,_Manufacturing": 0.9999997616, "qwen": "Yes"}
{"id": "8938230", "revid": "3632083", "url": "https://en.wikipedia.org/wiki?curid=8938230", "title": "List of bicycle part manufacturing companies", "text": "This article lists bicycle part manufacturers and brands past and present. For a list of bicycle manufacturers, see list of bicycle manufacturers.", "Engineering,_Manufacturing": 1.0000039339, "qwen": "Yes"}
{"id": "8948181", "revid": "589223", "url": "https://en.wikipedia.org/wiki?curid=8948181", "title": "Garter spring", "text": "A garter spring is a coiled steel spring that is connected at each end to create a circular shape, and is used in oil seals, shaft seals, belt-driven motors, and electrical connectors. Compression garter springs exert outward radial forces, while extension garter springs exert inward radial forces. The manufacturing process is not much different from the creation of regular coiled springs, with the addition of joining the ends together. Like most other springs, garter springs are typically manufactured with either carbon steel or stainless steel wire.\nTypes of Springs.\nCompression Springs.\nCompression garter springs are a type of coiled spring that exerts outward radial forces away from the center. They are typically made up of a thick steel wire with large coils; compression springs need to be able to handle very large loads while being able to return to their natural extended position. Compression springs store potential energy when they are compressed (length of spring decreases), and exert kinetic energy when released. Compression garter springs use this principle to withstand forces acting on it from outside. They may be placed inside a circular object to maintain the object's circular shape. This is similar to squeezing a rubber ball; the ball will contract when squeezed but will return to its natural state once the external pressure is released.\nExtension Springs.\nExtension garter springs are on the opposite side of the spring spectrum. Although they are also a type of coiled spring, extension garter springs exert inward radial forces that move toward the center. Extension springs store potential energy in their extended form and want to contract. Thinner wire and a greater number of coils allow extension springs to be able to contract quickly, which is essential when dealing with pressurized fluids and gases. Extension garter springs act against forces from the center, so they may be placed on the outside of a circular object to maintain the object's circular shape. They act similar to a bracelet, which is extended to fit around the hand and then snaps back into shape on the wrist. Extension garter springs are more common than compression garter springs because they use less material (smaller circumference and thinner wire) and they respond to changes quicker and more efficiently.\nManufacturing.\nProcess.\nThere are four main stages for the production of steel garter springs. The first step is to cut and coil reels of steel wire to produce normal coiled springs. The strength of the spring is proportional to the thickness of the wire. Compression springs are coiled in such a way that the coils are more spaced apart, while extension springs have no space between the coils.\nThe second step is to join each end of the spring to form the garter spring's unique circular shape. This can be accomplished through a few different ways:\nThe third stage is heat treating, which prevents the spring from being too brittle to function. Heat treating involves placing the spring in an oven at high temperature for a predetermined amount of time, and then letting it cool slowly.\nThe fourth stage is applying the finishing touches to the spring, which may include grinding (flattening the ends of the spring), shot peening (shooting tiny steel balls at the spring to harden the wire further), setting (permanently fixing the length and pitch of the spring), coating (electroplating or applying paint or rubber to the surface to prevent corrosion), and packaging.\nMaterials.\nCarbon steel wire is typically used for garter springs due to its affordable price and usability, in comparison to stainless steel. Carbon steel springs tend to have very high yield strengths, and are able to return to their original shape when temporarily deformed. The carbon content in carbon steel wires range from 0.50 to 0.95 percent. This relatively small amount of carbon is enough to improve the toughness of the spring. The close proximity to oil and high-pressure engines mean heat treated garter springs are essential for enduring temperatures over 100 °C (212 °F). However, carbon steel is not suitable for highly corrosive environments; stainless steel would be a more viable option. Stainless steel differs from carbon steel in the amount of chromium present; stainless steel has between 10.5% to 11% chromium by mass, while carbon steel has about 1%.\nApplications.\nMost garter springs are used for oil seals and shaft seals. Since they are able to withstand forces from all directions, garter springs are effective at handling changes in volume, pressure, temperature, and viscosity.", "Engineering,_Manufacturing": 1.000005126, "qwen": "Yes"}
{"id": "10694002", "revid": "45830091", "url": "https://en.wikipedia.org/wiki?curid=10694002", "title": "Industrial oven", "text": "An Industrial oven is a heated chamber that is used for a variety of industrial applications including drying, curing, and baking components. These different types of ovens can be useful in different industries such as bakeries and industrial manufacturing. These ovens play a big factor in many industries and without these machines, work all together would be very difficult. Also, without these machines work in factories, bakeries, and curing manufacturers would be nearly impossible without the industrial oven invented by Jordan Mott in 1833. John created the first coal oven called a base burner and had a ventilation to burn the coal efficiently.\nSuch ovens are used in many different applications, including chemical processing, food production, and even in the electronics industry, where circuit boards are run through a conveyor oven to attach surface mount components.\nSome common types of industrial ovens include:", "Engineering,_Manufacturing": 0.9997810721, "qwen": "Yes"}
{"id": "10700701", "revid": "15179295", "url": "https://en.wikipedia.org/wiki?curid=10700701", "title": "Manufacturing supermarket", "text": "A manufacturing supermarket (or market location) is, for a factory process, what a retail supermarket is for the customer. The customers draw products from the 'shelves' as needed and this can be detected by the supplier who then initiates a replenishment of that item. It was the observation that this 'way of working' could be transferred from retail to manufacturing that is one of the cornerstones of the Toyota Production System (TPS).\nHistory.\nIn the 1950s Toyota sent teams to the United States to learn how they achieved mass-production. However, the Toyota Delegation first got inspiration for their production system at an American Supermarket (a Piggly Wiggly, to be precise). They saw the virtue in the supermarket only reordering and restocking goods once they’d been bought by customers.\nIn a supermarket (like the TPS) customers (processes) buy what they need when they need it. Since the system is self-service the sales effort (materials management) is reduced. The shelves are refilled as products are sold (parts withdrawn) on the assumption that what has sold will sell again which makes it easy to see how much has been used and to avoid overstocking. The most important feature of a supermarket system is that stocking is triggered by actual demand. In the TPS this signal triggers the 'pull' system of production.\nImplementation.\nMarket locations are appropriate where there is a desire to communicate customer pull up the supply chain. The aim of the 'market' is to send single unit consumption signals back up the supply chain so that a demand leveling effect occurs. Just as in a supermarket it is possible for someone to decide to cater for a party of 300 from the supermarket so it is possible to decide to suddenly fill ten trucks and send massively distorting signals up those same pathways. Thus the 'market location' can be used as a sort of isolator between actual demand and how supply would like demand to be, an isolator between batch demand spikes and the up upstream supply process.\nFor example, if the market were positioned at the loading bay, then it will receive 'spikes' of demand whenever a truck comes in to be loaded. Since, in general, one knows in advance when trucks will arrive and what they will require to be loaded onto them, it is possible to spread that demand spike over a chosen period before the truck actually arrives. It is possible to do this by designating a location, say a marked floor area, to be the 'virtual' truck and moving items from the market to the 'virtual truck' smoothly over the chosen period prior to the load onto the actual truck commencing. Smoothly here means that for each item its 'loading' is evenly spread across the period. For regular shipments this period might start the moment the last shipment in that schedule departs the loading bay. This has four key impacts:\nThis logic can, obviously, be applied upstream of any batch process and not just deliveries to another plant. It is a workaround for the fact that the batch process hasn't been made to flow yet. It therefore has some costs but the benefits in terms of reducing the three wastes should outweigh these.\nToyota use this technique and demand it of their suppliers in order to generate focus on the supply issues it uncovers. They then demand the preparation of loads for more frequent 'virtual' trucks than will actually appear in order to raise this pressure (see Frequent deliveries).\nAt low stocking levels for some items the 'market location' can require Just in Sequence supply rather than Just in Time.", "Engineering,_Manufacturing": 0.9981290698, "qwen": "Yes"}
{"id": "10708263", "revid": "4743453", "url": "https://en.wikipedia.org/wiki?curid=10708263", "title": "Blood (automobile)", "text": "The Blood was an automobile manufactured in Kalamazoo, Michigan, by the Blood Brothers Auto & Machine Company from 1902 to 1905. They produced a five-seater tonneau with a two-cylinder opposed engine, costing $1,800. The drive system had a four-speed transmission and transferred power to the rear axle by a shaft.\nMaurice & Clarence Blood were owners of a bicycle shop at 210 N. Rose St, in Kalamazoo. They sold a Mobile Steam car to Oscar Buckout in 1901, making them the first automotive dealership in Kalamazoo. \nThey eventually built and sold 150 Blood cars. In 1905, they ceased building automobiles, and concentrated on universal joints in a small factory. Maurice's son, Howard, later built the Cornelian Cyclecar.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "64298892", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=64298892", "title": "Production and Operations Management Society", "text": "The Production and Operations Management Society (POMS) is an international professional society for academics and practitioners with interests in production operations, operations management, and supply chain management. The society was established in 1989 by Kalyan Singhal, of Merrick School of Business at the University of Baltimore, in collaboration with three hundred professionals from the operations management field.\nSince 1990, the POMS society has annually held national conferences focused on academic and practitioner research presentations in the operations management discipline. POMS also sponsors conferences held by its Colleges, joint conferences with the European operations management society EUROMA, and international conferences. The society maintains the website www.pomsmeetings.org as a current and historical repository of information about these conferences.\nThe current President of POMS is Chelliah Siskandarajah, who is the Hugh Roy Cullen Chair in Business Administration Information and Operations Management at Mays Business School, Texas A&M University. The President-Elect is Zuojun (Max) Shen from University of California Berkeley. POMS also is guided by Board Members made up of three Past Presidents, several Vice Presidents (e.g., Education, Finance, Meetings, Member Activities, Colleges, Publications, Communications, Industry, Americas, Africa & Middle East, Europe, and Australasia), a Secretary, and several at-large Board Members. POMS is also led by a Director of Strategic Planning, an Executive Director, Associate Directors (Global Outreach, Information Technology Services), a Web Editor, and a Social Media Coordinator.\nThe mission of POMS is to create, extend, and disseminate knowledge in the field of production and operations management.\nPOMS activities.\nPublications.\nProduction and Operations Management (POM) is the flagship journal of the society. POM is a scientific peer-review journal that publishes research from areas covering operations management, supply chain management, and business analytics. The journal is published by Wiley. The editor-in-chief for the journal is Kalyan Singhal. Subodha Kumar is the deputy editor-in-chief. POM is included among several lists of top journals for the Operations Management and Supply Chain Management fields, including by the UT Dallas Top 100 Business School Research Rankings, the Financial Times list, and other lists. POM is included among the top eight operations management and supply chain management journals used to calculate The SCM Journal List, being considered as a primarily analytically-focused journal. \nPOMS Chronicle is the official newsletter of the society and is published twice a year.\nConferences.\nThe annual POMS conference is generally held in the early May. The most recent conference (2019 POMS Annual Conference) was held in Washington D.C. It was attended by more than 1900 professionals from around the world. In addition to the Annual conferences, several international conferences are held every year around the world. In 2019, international conferences were held in Brighton (UK), Tianjin University (China), Mumbai (India), and Hong Kong.\nChapters.\nPOMS society has chapters in Beijing, India, Hong Kong, Latin America, Caribbean, and Taiwan.\nAwards.\nPOMS recognizes scholars and practitioners from POM field by bestowing awards in various accomplishments. They include:\nHistory.\nThe society was established in 1989 by Kalyan Singhal, of Merrick School of Business at the University of Baltimore, in collaboration with three hundred professionals from the operations management field.\nPresidents.\nPresidents of POMS have included:", "Engineering,_Manufacturing": 0.9972331524, "qwen": "Yes"}
{"id": "565255", "revid": "143538", "url": "https://en.wikipedia.org/wiki?curid=565255", "title": "Vendor-managed inventory", "text": "Vendor-managed inventory (VMI) is an inventory management practice in which a supplier of goods, usually the manufacturer, is responsible for optimizing the inventory held by a distributor.\nUnder VMI, the retailer shares their inventory data with a vendor (sometimes called supplier) such that the vendor is the decision-maker who determines the order size, whereas in traditional inventory management, the retailer (sometimes called distributor or buyer) makes his or her own decisions regarding the order size. Thus, the vendor is responsible for the retailer's ordering cost, while the retailer usually acquires ownership of the stock and has to pay for their own holding cost. One supply chain management glossary identifies VMI as although a 2008 article notes that there is no standard definition of VMI and the term's usage varies \"significantly\" among companies supporting VMI processes.\nA third-party logistics provider may also be involved to help ensure that the buyer has the required level of inventory by adjusting the demand and supply gaps.\nOverview.\nOne of the keys to making VMI work is shared risk. In some cases, if the inventory does not sell, the vendor (supplier) will repurchase the product from the buyer (retailer). In other cases, the product may be in the possession of the retailer but is not owned by the retailer until the sale takes place, meaning that the retailer simply houses (and assists with the sale of) the product in exchange for a predetermined commission or profit (sometimes referred to as consignment stock). A special form of this commission business is scan-based trading, where VMI is usually applied but its use is not mandatory.\nThis is one of the successful business models used by Walmart, Procter & Gamble and many other big box retailers. Oil companies often use technology to manage the gasoline inventories at the service stations that they supply (see Petrolsoft Corporation). Home Depot uses the technique with larger suppliers of manufactured goods. VMI helps foster a closer understanding between the supplier and manufacturer by using electronic data interchange formats, EDI software and statistical methodologies to forecast and maintain correct inventory in the supply chain.\nVendors benefit from more control of displays and more customer contact for their employees; retailers benefit from reduced risk, better store staff knowledge (which builds brand loyalty for both the vendor and the retailer), and reduced display maintenance outlays.\nUsage of VMI can prevent stocking undesired inventories and hence can lead to an overall cost reduction. Moreover, the magnitude of the bullwhip effect is also reduced by employing the VMI approach in a buyer-supplier cooperation.\nConsumers benefit from knowledgeable store staff who are in frequent and familiar contact with manufacturer (vendor) representatives when parts or service are required. Store staff have good knowledge of most product lines offered by the entire range of vendors. They can help the consumer choose from competing products for items most suited to them and offer service support being offered by the store.\nAt the goods manufacturing level, VMI helps prevent overflowing warehouses or shortages, as well as costly labor, purchasing and accounting. With VMI, businesses maintain a proper inventory, and optimized inventory leads to easy access and fast processing with reduced labor costs.\nVariant models include \"consigned VMI\", where the supplier or manufacturer retains ownership, and \"dynamic VMI\", where the buffer inventory remains located with the supplier, which can be beneficial if the supplier and retailer are located close enough together, and allows for buffer stock to be shared among distributors.\nAs a symbiotic business relationship, VMI makes it less likely that a business will unintentionally run out of stock of a good and reduces inventory in the supply chain. Furthermore, vendor (supplier) representatives in a store benefit the vendor by ensuring the product is properly displayed and store staff are familiar with the features of the product line, all these while helping to clean and organize their product lines for the store. However, high-tech sector research undertaken in 2003 concluded that under VMI, \"sizeable inventory burdens [are transferred] from the customer to the supplier\" and that \"significant additional operating expenses for the supplier\" therefore arise.\nComponents.\n1. Inventory location\nIn VMI practice, inventory location depends on the arrangement between the vendor and the customer. The first option is for the inventory to be located both at the customer's and the supplier's premises. For the supplier, this serves as a safeguard against short delivery cycles or unsynchronized production cycles. On the other hand, this arrangement can also lead to higher inventory holding costs because of the need for storage of the material, its tracking and handling, and the threat of inventory obsolescence.\nAnother option can be for the vendor to deliver to the customer's central warehouse or alternatively, to a third party's warehouse. The latter can be a solution for buyers that have outsourced part or all of their logistics operations. Managing the inventory at the central warehouse enables better optimization of deliveries, lower costs and ultimately enables the buyer to maximize economies of scale. However, it is not always an option, so third-party warehouses are often the solution to many different problems such as the supplier's warehouse being too far away from the buyer's or the buyer's inexperience in storing particular types of goods that are harder to store.\nThe inventory can also be located directly at the buyer's premises such as the buyer's on-site warehouse, production line or the shop floor itself. However, replenishing inventory levels at these specific locations can be more costly, less organized and overall more difficult to manage for the supplier.\n2. Inventory Ownership\nInventory ownership refers to the ownership of the inventory and when the invoice is being issued to the retailer. In vendor managed inventory, there is a number of solutions in terms of payment and transfer of ownership.\nIn the first alternative, the vendor is the owner of inventory at the premises of the customer. Invoice is issued when the items are issued from the stock. In the second alternative, the retailer assumes ownership of the inventory, but receives an invoice upon delivery. However, the vendor is not paid until the customer issues the items from stock and within a delay according to agreed terms of payment. This enables risk-sharing between both parties, as the retailer carries risk of obsolescence while the vendor would have been accountable for capital costs and fluctuation in prices of the inventory.\nIn the third alternative, also referred to as a standard process in traditional order delivery, the retailer owns the inventory upon delivery, while the vendor invoices the retailer once the shipment has been made. In this setting, retailer is responsible for inventory investment and holding costs, but has an option of protecting themselves against price fluctuations.\n3. Level of Demand Visibility\nThese elements refer to the type of demand information shared by customers to assist the suppliers in controlling their inventory. Many types of demand information are shared in the VMI Program. The demand information that are visible to the supplier are: sales data, stock withdrawal, production schedule, inventory level, goods in transit, back order, incoming order and return. It is argued that sharing data and inventory can improve the supplier’s production planning, make it more stable and increase its visibility. It also provides a better understanding of the seasonal changes, and helps to figure out critical times. The supplier can therefore take advantage of this information and adapt its production to the customers’ requests, and respond faster. With the increasing visibility of information, the supplier has a longer timeframe for replenishment arrangement.\nThe supplier also gets real time visibility, which allows him to have a hand on the inventory for the buyer demand forecast, which allows for projecting inventory based on future demand to target his inventory (minimize or maximize it). This stability and coordination allows to reduce the bullwhip effect, as the manufacturer has a clearer visibility on the supply chain and an overview of the incoming demand. On the retailer’s side, all the costs associated with inventory management, (holding costs, shortage costs, spoilage costs, etc.) are greatly reduced. E.g., the retailer will rarely face stock shortage and holding costs are kept at a minimum since just enough inventory is held.\nData is usually updated every week and is transmitted through an EDI, which allows forecasting actual market trends. The data is based on real quantities of produced and sold items. This agreement to share information is aimed at maintaining a steady flow of necessary goods.\nClasses of mathematical model.\n1. Bi-Level VMI Mathematical Models\nThe first class of VMI, bi-level VMI mathematical model, includes two levels (or echelons) in a supply chain: vendor and retailer. There are three types of VMI mathematical models developed from this class, which are single-vendor single-retailer VMI model, single-vendor multi-retailer VMI model, and multi-vendor multi-retailer VMI model. This class has been significantly developing. For example, single-vendor single-retailer VMI model was extended for multi-product case, the consignment stock (CS), and discount.\n2. Multi-Level VMI Mathematical Models\nThe second class is a multi-level VMI mathematical model such as a single manufacturer-single vendor multi-retailer (SM-SV-MR) VMI model. Those studies [which] fail to model replenishment frequencies cannot be classified here.\nReplenishment frequencies play an important role in integrated inventory models to reduce the total supply chain cost, but it has been noted that many studies fail to model it in mathematical problems.", "Engineering,_Manufacturing": 0.9995305538, "qwen": "Yes"}
{"id": "21329799", "revid": "33865157", "url": "https://en.wikipedia.org/wiki?curid=21329799", "title": "Abrasive jet machining", "text": "Abrasive jet machining (AJM), also known as abrasive micro-blasting, pencil blasting and micro-abrasive blasting, is an abrasive blasting machining process that uses abrasives propelled by a high velocity gas to erode material from the workpiece. Common uses include cutting heat-sensitive, brittle, thin, or hard materials. Specifically it is used to cut intricate shapes or form specific edge shapes.\nProcess.\nMaterial is removed by fine abrasive particles, usually about in diameter, driven by a high velocity fluid stream; common gases are air or inert gases. Pressures for the gas range from 25 to 130 psig (170–900 kPa or 4 bars) and speeds can be as high as 300 m/s (1,000 km/h).\nEquipment.\nAJM machines are usually self-contained bench-top units. First it compresses the gas and then mixes it with the abrasive in a mixing chamber. The gas passes through a convergent-divergent nozzle before entering the mixing chamber, and then exits through a convergent nozzle. The nozzle can be hand held or mounted in a fixture for automatic operations.\nNozzles must be highly resistant to abrasion and are typically made of tungsten carbide or synthetic sapphire. For average material removal, tungsten carbide nozzles have a useful life of 12 to 30 hours, and sapphire nozzles last about 400 hours. The distance of the nozzle from the workpiece affects the size of the machined area and the rate of material removal.\nAdvantages and disadvantages.\nThe main advantages are its flexibility, low heat production, and ability to machine hard and brittle materials. Its flexibility owes from its ability to use hoses to transport the gas and abrasive to any part of the workpiece. Normally inaccessible portion can be machined with good accuracy. \nOne of the main disadvantages is its slow material removal rate; for this reason it is usually used as a finishing process. Another disadvantage is that the process produces a tapered cut.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "21345284", "revid": "82432", "url": "https://en.wikipedia.org/wiki?curid=21345284", "title": "Surface grinding", "text": "Surface grinding is done on flat surfaces to produce a smooth finish. \nIt is a widely used abrasive machining process in which a spinning wheel covered in rough particles (grinding wheel) cuts chips of metallic or nonmetallic substance from a workpiece, making a face of it flat or smooth.\nSometimes a surface grinder is known as a \"flick grinder\" if great accuracy is not required, but a machine superior to a bench grinder is needed. \nProcess.\nSurface grinding is a finishing process that uses a rotating abrasive wheel to smooth the flat surface of metallic or nonmetallic materials to give them a more refined look by removing the oxide layer and impurities on work piece surfaces. This will also attain a desired surface for a functional purpose.\nThe components of a surface grinding machine are an abrasive wheel, a workholding device known as a chuck, and a reciprocating or rotary table. The chuck holds the material in place by two processes: ferromagnetic pieces are held in place by a magnetic chuck, while non-ferromagnetic and nonmetallic pieces are held in place with vacuum or mechanical means. A machine vise (made from ferromagnetic steel or cast iron) placed on the magnetic chuck can be used to hold non-ferromagnetic workpieces if only a magnetic chuck is available. \nFactors to consider in surface grinding are the material of the grinding wheel and the material of the piece being worked on.\nTypical workpiece materials include cast iron and mild steel. These two materials don't tend to clog the grinding wheel while being processed. Other materials are aluminum, stainless steel, brass and some plastics. When grinding at high temperatures, the material tends to become weakened and is more inclined to corrode. This can also result in a loss of magnetism in materials where this is applicable.\nThe grinding wheel is not limited to a cylindrical shape and can have a myriad of options that are useful in transferring different geometries to the object being worked on. Straight wheels can be dressed by the operator to produce custom geometries. When surface grinding an object, one must keep in mind that the shape of the wheel will be transferred to the material of the object like a reverse image.\n\"Spark out\" is a term used when precision values are sought and literally means \"until the sparks are out (no more)\". It involves passing the workpiece under the wheel, without resetting the depth of cut, more than once and generally multiple times. This ensures that any inconsistencies in the machine or workpiece are eliminated.\nEquipment.\nA surface grinder is a machine tool used to provide precision ground surfaces, either to a critical size or for the surface finish.\nThe typical precision of a surface grinder depends on the type and usage, however ±0.002 mm (±0.0001 in) should be achievable on most surface grinders. \nThe machine consists of a table that traverses both longitudinally and across the face of the wheel. The longitudinal feed is usually powered by hydraulics, as may the cross feed, however any mixture of hand, electrical or hydraulic may be used depending on the ultimate usage of the machine (i.e., production, workshop, cost). The grinding wheel rotates in the spindle head and is also adjustable for height, by any of the methods described previously. Modern surface grinders are semi-automated, depth of cut and spark-out may be preset as to the number of passes and, once set up, the machining process requires very little operator intervention.\nDepending on the workpiece material, the work is generally held by the use of a magnetic chuck. This may be either an electromagnetic chuck, or a manually operated, permanent magnet type chuck; both types are shown in the first image.\nThe machine has provision for the application of coolant as well as the extraction of metal dust (metal and grinding particles).\nTypes of surface grinders.\nHorizontal-spindle (peripheral) surface grinders.\nThe periphery (flat edge) of the wheel is in contact with the workpiece, producing the flat surface. Peripheral grinding is used in high-precision work on simple flat surfaces; tapers or angled surfaces; slots; flat surfaces next to shoulders; recessed surfaces; and profiles.\nVertical-spindle (wheel-face) grinders ..\nThe face of a wheel (cup, cylinder, disc, or segmental wheel) is used on the flat surface. Wheel-face grinding is often used for fast material removal, but some machines can accomplish high-precision work. The workpiece is held on a reciprocating table, which can be varied according to the task, or a rotary-table machine, with continuous or indexed rotation. Indexing allows loading or unloading one station while grinding operations are being performed on another. An alternative term is snow grinding.\nDisc grinders and double-disc grinders..\nDisc grinding is similar to surface grinding, but with a larger contact area between disc and workpiece. Disc grinders are available in both vertical and horizontal spindle types. Double disc grinders work both sides of a workpiece simultaneously. Disc grinders are capable of achieving especially fine tolerances.\nGrinding wheels for surface grinders.\nAluminum oxide, silicon carbide, diamond, and cubic boron nitride (CBN) are four commonly used abrasive materials for the surface of the grinding wheels. Of these materials, aluminum oxide is the most common. Because of cost, diamond and CBN grinding wheels are generally made with a core of less expensive material surrounded by a layer of diamond or CBN. Diamond and CBN wheels are very hard and are capable of economically grinding materials, such as ceramics and carbides, that cannot be ground by aluminum oxide or silicon.\nAs with any grinding operation, the condition of the wheel is extremely important. Grinding dressers are used to maintain the condition of the wheel, these may be table mounted or mounted in the wheel head where they can be readily applied.\nLubrication.\nLubricants are sometimes used to cool the workpiece and wheel, lubricate the interface, and remove swarf (chips). It must be applied directly to the cutting area to ensure that the fluid is not carried away by the grinding wheel. Common lubricants include water-soluble chemical fluids, water-soluble oils, synthetic oils, and petroleum-based oils. The type of lubrication used depends on the workpiece material and is outlined in the table below.\nEffects on work material properties.\nThe high temperatures encountered at the ground surface create residual stresses and a thin martensitic layer may form on the part surface; this decreases the fatigue strength. In ferromagnetic materials, if the temperature of the surface is raised beyond the Curie temperature then it may lose some magnetic properties. Finally, the surface may be more susceptible to corrosion.", "Engineering,_Manufacturing": 0.9999499321, "qwen": "Yes"}
{"id": "648007", "revid": "2414730", "url": "https://en.wikipedia.org/wiki?curid=648007", "title": "Die (manufacturing)", "text": "A die is a specialized machine tool used in manufacturing industries to cut and/or form material to a desired shape or profile. Stamping dies are used with a press, as opposed to drawing dies (used in the manufacture of wire) and casting dies (used in molding) which are not. Like molds, dies are generally customized to the item they are used to create.\nProducts made with dies range from simple paper clips to complex pieces used in advanced technology. Continuous-feed laser cutting may displace the analogous die-based process in the automotive industry, among others.\nDie stamping.\nBlanking and piercing are two die cutting operations, and bending is an example of a die forming operation.\nDie forming.\nForming operations work by deforming materials like sheet metal or plastic using force (compression, tension, or both) and rely on the material's mechanical properties. Forming dies are typically made by tool and die makers and put into production after mounting into a press.\nDifferences between materials.\nFor the vacuum forming of plastic sheet only a single form is used, typically to form transparent plastic containers (called blister packs) for merchandise. Vacuum forming is considered a simple molding thermoforming process but uses the same principles as die forming.\nFor the forming of sheet metal, such as automobile body parts, two parts may be used: one, called the \"punch\", performs the stretching, bending, and/or blanking operation, while another part that is called the \"die block\" securely clamps the workpiece and provides similar stretching, bending, and/or blanking operation. The workpiece may pass through several stages using different tools or operations to obtain the final form. In the case of an automotive component, there will usually be a shearing operation after the main forming is done. Additional crimping or rolling operations may be performed to ensure that all sharp edges are hidden and/or to add rigidity to the panel.\nDie components.\nThe main components of a die set (including press mounting) are as follows. Note that because nomenclature varies between sources, alternate names are in parenthesis:\nSteel-rule die.\n\"Steel-rule\" die, also known as \"cookie cutter\" dies, are used for cutting sheet metal and softer materials, such as plastics, wood, cork, felt, fabrics, and paperboard. The cutting surface of the die is the edge of hardened steel strips, known as \"steel rule\". These steel rules are usually located using saw or laser-cut grooves in plywood. The mating die can be a flat piece of hardwood or steel, a male shape that matches the workpiece profile, or it can have a matching groove that allows the rule to nest into. Rubber strips are wedged in with the steel rule to act as the stripper plate; the rubber compresses on the down-stroke and on the up-stroke it pushes the workpiece out of the die. The main advantage of steel-rule dies is the low cost to make them, as compared to solid dies; however, they are not as robust as solid dies, so they are usually only used for short production runs.\nRotary die.\nIn the broadest sense, a \"rotary die\" is a cylindrical shaped die that may be used in any manufacturing field. However, it most commonly refers to cylindrical shaped dies used to process soft materials, such as paper or cardboard. Two rules are used, cutting and creasing rules. This is for corrugated boards whose thickness is more than 2 mm. Rotary dies are faster than flat dies.\nThe term also refers to dies used in the roll forming process.\nWire pulling.\nWire-making dies have a hole through the middle of them. A wire or rod of steel, copper, other metals, or alloy enters into one side and is lubricated and reduced in size. The leading tip of the wire is usually pointed in the process. The tip of the wire is then guided into the die and rolled onto a block on the opposite side. The block provides the power to pull the wire through the die.\nThe die is divided into several different sections. First is an entrance angle that guides the wire into the die. Next is the approach angle, which brings the wire to the nib, which facilitates the reduction. Next is the bearing and the back relief. Lubrication is added at the entrance angle. The lube can be in powdered soap form. If the lubricant is soap, the friction of the drawing of wire heats the soap to liquid form and coats the wire. The wire should never actually come in contact with the die. A thin coat of lubricant should prevent the metal to metal contact.\nFor pulling a substantial rod down to a fine wire a series of several dies is used to obtain progressive reduction of diameter in stages.\nStandard wire gauges used to refer to the number of dies through which the wire had been pulled. Thus, a higher-numbered wire gauge meant a thinner wire. Typical telephone wires were 22-gauge, while main power cables might be 3- or 4-gauge.", "Engineering,_Manufacturing": 0.9998627901, "qwen": "Yes"}
{"id": "54590538", "revid": "20275651", "url": "https://en.wikipedia.org/wiki?curid=54590538", "title": "Stankoprom", "text": "Stankoprom  is a Russian designer and manufacturer of machine tools based in Moscow. It was established in 2013 as part as Russia's Import substitution strategy to reduce the country's reliance on foreign-made machine tools. It includes scientific centers as well as manufacturing plants.\nStankoprom is part of the state-owned holding company Rostec, and it incorporates 14 machine tool manufacturers.\nStructure.\nStructure of the company:", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "16384086", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=16384086", "title": "Job-shop scheduling", "text": "Job-shop scheduling, the job-shop problem (JSP) or job-shop scheduling problem (JSSP) is an optimization problem in computer science and operations research. It is a variant of optimal job scheduling. In a general job scheduling problem, we are given \"n\" jobs \"J\"1, \"J\"2, ..., \"Jn\" of varying processing times, which need to be scheduled on \"m\" machines with varying processing power, while trying to minimize the makespan – the total length of the schedule (that is, when all the jobs have finished processing). In the specific variant known as \"job-shop scheduling\", each job consists of a set of \"operations\" \"O\"1, \"O\"2, ..., \"On\" which need to be processed in a specific order (known as \"precedence constraints\"). Each operation has a \"specific machine\" that it needs to be processed on and only one operation in a job can be processed at a given time. A common relaxation is the flexible job shop, where each operation can be processed on any machine of a given \"set\" (the machines in each set are identical).\nThe name originally came from the scheduling of jobs in a job shop, but the theme has wide applications beyond that type of instance. This problem is one of the best known combinatorial optimization problems, and was the first problem for which competitive analysis was presented, by Graham in 1966. Best problem instances for basic model with makespan objective are due to Taillard.\nIn the standard three-field notation for optimal job scheduling problems, the job-shop variant is denoted by J in the first field. For example, the problem denoted by \" J3|formula_1|formula_2\" is a 3-machines job-shop problem with unit processing times, where the goal is to minimize the maximum completion time.\nProblem variations.\nMany variations of the problem exist, including the following:\nNP-hardness.\nSince the traveling salesman problem is NP-hard, the job-shop problem with sequence-dependent setup is clearly also NP-hard since the TSP is a special case of the JSP with a single job (the cities are the machines and the salesman is the job).\nProblem representation.\nThe disjunctive graph is one of the popular models used for describing the job-shop scheduling problem instances.\nA mathematical statement of the problem can be made as follows:\nLet formula_3 and formula_4 be two finite sets. On account of the industrial origins of the problem, the formula_5 are called machines and the formula_6 are called jobs.\nLet formula_7 denote the set of all sequential assignments of jobs to machines, such that every job is done by every machine exactly once; elements formula_8 may be written as formula_9 matrices, in which column formula_10 lists the jobs that machine formula_5 will do, in order. For example, the matrix\nmeans that machine formula_13 will do the three jobs formula_14 in the order formula_14, while machine formula_16 will do the jobs in the order formula_17.\nSuppose also that there is some cost function formula_18. The cost function may be interpreted as a \"total processing time\", and may have some expression in terms of times formula_19, the cost/time for machine formula_5 to do job formula_6.\nThe job-shop problem is to find an assignment of jobs formula_8 such that formula_23 is a minimum, that is, there is no formula_24 such that formula_25.\nScheduling efficiency.\nScheduling efficiency can be defined for a schedule through the ratio of total machine idle time to the total processing time as below:\nformula_26\nHere formula_27 is the idle time of machine formula_28, formula_29 is the makespan and formula_30 is the number of machines. Notice that with the above definition, scheduling efficiency is simply the makespan normalized to the number of machines and the total processing time. This makes it possible to compare the usage of resources across JSP instances of different size.\nThe problem of infinite cost.\nOne of the first problems that must be dealt with in the JSP is that many proposed solutions have infinite cost: i.e., there exists formula_31 such that formula_32. In fact, it is quite simple to concoct examples of such formula_33 by ensuring that two machines will deadlock, so that each waits for the output of the other's next step.\nMajor results.\nGraham had already provided the List scheduling algorithm in 1966, which is -competitive, where m is the number of machines. Also, it was proved that List scheduling is optimum online algorithm for 2 and 3 machines. The Coffman–Graham algorithm (1972) for uniform-length jobs is also optimum for two machines, and is -competitive. In 1992, Bartal, Fiat, Karloff and Vohra presented an algorithm that is 1.986 competitive. A 1.945-competitive algorithm was presented by Karger, Philips and Torng in 1994. In 1992, Albers provided a different algorithm that is 1.923-competitive. Currently, the best known result is an algorithm given by Fleischer and Wahl, which achieves a competitive ratio of 1.9201.\nA lower bound of 1.852 was presented by Albers.\nTaillard instances has an important role in developing job-shop scheduling with makespan objective.\nIn 1976 Garey provided a proof that this problem is NP-complete for m>2, that is, no optimal solution can be computed in deterministic polynomial time for three or more machines (unless P=NP).\nIn 2011 Xin Chen et al. provided optimal algorithms for online scheduling on two related machines improving previous results.\nOffline makespan minimization.\nAtomic jobs.\nThe simplest form of the offline makespan minimisation problem deals with atomic jobs, that is, jobs that are not subdivided into multiple operations. It is equivalent to packing a number of items of various different sizes into a fixed number of bins, such that the maximum bin size needed is as small as possible. (If instead the number of bins is to be minimised, and the bin size is fixed, the problem becomes a different problem, known as the bin packing problem.)\nDorit S. Hochbaum and David Shmoys presented a polynomial-time approximation scheme in 1987 that finds an approximate solution to the offline makespan minimisation problem with atomic jobs to any desired degree of accuracy.\nJobs consisting of multiple operations.\nThe basic form of the problem of scheduling jobs with multiple (M) operations, over M machines, such that all of the first operations must be done on the first machine, all of the second operations on the second, etc., and a single job cannot be performed in parallel, is known as the flow-shop scheduling problem. Various algorithms exist, including genetic algorithms.\nJohnson's algorithm.\nA heuristic algorithm by S. M. Johnson can be used to solve the case of a 2 machine N job problem when all jobs are to be processed in the same order. The steps of algorithm are as follows:\nJob Pi has two operations, of duration Pi1, Pi2, to be done on Machine M1, M2 in that sequence.\nIf the minimum belongs to Pk1,\nRemove K from list A; Add K to end of List L1.\nIf minimum belongs to Pk2,\nRemove K from list A; Add K to beginning of List L2.\nJohnson's method only works optimally for two machines. However, since it is optimal, and easy to compute, some researchers have tried to adopt it for M machines, (\"M\" > 2.)\nThe idea is as follows: Imagine that each job requires m operations in sequence, on M1, M2 … Mm. We combine the first \"m\"/2 machines into an (imaginary) Machining center, MC1, and the remaining Machines into a Machining Center MC2. Then the total processing time for a Job P on MC1 = sum( operation times on first \"m\"/2 machines), and processing time for Job P on MC2 = sum(operation times on last \"m\"/2 machines).\nBy doing so, we have reduced the m-Machine problem into a Two Machining center scheduling problem. We can solve this using Johnson's method.\nMakespan prediction.\nMachine learning has been recently used to \"predict\" the optimal makespan of a JSP instance without actually producing the optimal schedule. Preliminary results show an accuracy of around 80% when supervised machine learning methods were applied to classify small randomly generated JSP instances based on their optimal scheduling efficiency compared to the average.\nExample.\nHere is an example of a job-shop scheduling problem formulated in AMPL as a mixed-integer programming problem with indicator constraints:\nparam N_JOBS;\nparam N_MACHINES;\nset JOBS ordered = 1..N_JOBS;\nset MACHINES ordered = 1..N_MACHINES;\nparam ProcessingTime{JOBS, MACHINES} > 0;\nparam CumulativeTime{i in JOBS, j in MACHINES} =\n sum {jj in MACHINES: ord(jj) <= ord(j)} ProcessingTime[i,jj];\nparam TimeOffset{i1 in JOBS, i2 in JOBS: i1 i2} =\n (CumulativeTime[i1,j] - CumulativeTime[i2,j] + ProcessingTime[i2,j]);\nvar end >= 0;\nvar start{JOBS} >= 0;\nvar precedes{i1 in JOBS, i2 in JOBS: ord(i1) < ord(i2)} binary;\nminimize makespan: end;\nsubj to makespan_def{i in JOBS}:\n end >= start[i] + sum{j in MACHINES} ProcessingTime[i,j];\nsubj to no12_conflict{i1 in JOBS, i2 in JOBS: ord(i1) < ord(i2)}:\n precedes[i1,i2] ==> start[i2] >= start[i1] + TimeOffset[i1,i2];\nsubj to no21_conflict{i1 in JOBS, i2 in JOBS: ord(i1) < ord(i2)}:\n !precedes[i1,i2] ==> start[i1] >= start[i2] + TimeOffset[i2,i1];\ndata;\nparam N_JOBS := 4;\nparam N_MACHINES := 4;\nparam ProcessingTime:\n1 2 3 4 :=\n1 4 2 1\n2 3 6 2\n3 7 2 3\n4 1 5 8;", "Engineering,_Manufacturing": 0.9983293414, "qwen": "Yes"}
{"id": "16399375", "revid": "9487993", "url": "https://en.wikipedia.org/wiki?curid=16399375", "title": "Hyundai IHL", "text": "Hyundai IHL Co., Ltd. is an automotive components manufacturing company headquartered in Gyeongju, South Korea. It was established in 1993 as Inhee Industrial Co. and changed its name to IHL in 2005. Its principal products are car lights.\nReferences.\nhttps://web.archive.org/web/20110726114213/http://www.hankyung.com/news/app/newsview.php?aid=2008011466141", "Engineering,_Manufacturing": 1.0000002384, "qwen": "Yes"}
{"id": "63366496", "revid": "35498457", "url": "https://en.wikipedia.org/wiki?curid=63366496", "title": "Lacoste & Battmann", "text": "Lacoste & Battmann, Lacoste et Battmann, was a French manufacturer of automobiles, based in Paris, from 1897 until 1913.\nCompany history.\nJacques Lacoste founded the company J. Lacoste et Cie in Paris in 1897 for automobile production. In 1901 the name was changed to Lacoste & Battmann and 1905 in Lacoste & Battmann Ltd.\nThe company sold limited numbers of finished vehicles under its own name, and via its own marques: (1905) and . In addition finished chassis, equipped with Aster, De Dion-Bouton or Mutel engines, were supplied to competing companies such as : , Horley Motor & Engineering Co. Ltd (sold as \"Horley\" and \"No Name\"), Imperial, Simplicia and , which completed the chassis and bodywork to offer complete cars under their own names.\nProduction ended in 1913.", "Engineering,_Manufacturing": 0.9987742901, "qwen": "Yes"}
{"id": "33311504", "revid": "23899575", "url": "https://en.wikipedia.org/wiki?curid=33311504", "title": "Nova Measuring Instruments", "text": "Nova Ltd. (formerly Nova Measuring Instruments) is a publicly traded company, headquartered in Israel, a provider of metrology devices for advanced process control used in semiconductor manufacturing. Shares of the company are traded on the NASDAQ Global Market and on the Tel Aviv Stock Exchange.\nHistory.\nNova Ltd. was founded in May 1993 by Giora Dishon and Moshe Finarov. Dishon graduated from the Hebrew University of Jerusalem with a Ph.D in materials science. Finarov earned a Ph.D in semiconductor physics from the Technical University in Moscow.\nIntel Corporation became a client of and investor in Nova in 1997. In 1999 Nova announced the establishment of a subsidiary in Japan, Nova Measuring Instruments K.K., and that it was opening offices in Singapore in order to expand its presence in the Asia-Pacific market. Nova executed its initial public offering on the NASDAQ exchange in April 2000. In 2006 Nova acquired HyperNex Inc., a Pennsylvania-based developer of microstructure analysis tools.", "Engineering,_Manufacturing": 0.9999647141, "qwen": "Yes"}
{"id": "33325509", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=33325509", "title": "Item-level tagging", "text": "Item-level tagging (or RFID item-level tagging, also known as ILT) is the tagging of individual products, as opposed to case-level and pallet-level tagging.\nItem-level tagging is used to track individual items in order to better control inventory, by providing retailers with the ability to tag individual items on the retail floor.\nPreviously, RFID tags were used to track pallets of merchandise, rather than individual items, through the supply chain. With the use of printed RFID tags, retailers are now able to track inventory at the item level, scan the tag, and know the location.\nRetailers are pushing for tagging each individual item. In fact, large companies like Wal-Mart, JC Penney, and Dillard’s are issuing electronic product code mandates, where they request their suppliers to comply with these EPC protocols. In 2005, it was required that the suppliers use RFID tagging at the pallet and case level, but now it is required that they tag on the item-level as well. The reason why is it so important for them to implement this is because they want to avoid losing a sale over an out-of-stock item, which they believe accounts for a big part of their losses. Also, if they know where an item is at all times then it easier to move it to where it is supposed to be. By doing this they reduce transportation costs, they gain added shelf visibility and it drives down wasteful overstock.\nBenefits.\nItem-level tagging provides a quick, automated, cost efficient and accurate way to track inventory through the supply chain and in the retail environment.\nBenefits to item-level tagging include better visibility and control of inventory and an expansion of customer experience capabilities.\nItem-level tagging is critical in order to determine how much inventory is on the floor, what sizes and colors need to be restocked and what inventory is available in stock rooms. Other benefits include the ability to keep a fully stocked floor, increased time and labor savings, increase inventory accuracy, and reduction in clearance items due to incorrect inventory and excess ordering.", "Engineering,_Manufacturing": 0.9998519421, "qwen": "Yes"}
{"id": "1949447", "revid": "1161861911", "url": "https://en.wikipedia.org/wiki?curid=1949447", "title": "Motion control", "text": "Motion control is a sub-field of automation, encompassing the systems or sub-systems involved in moving parts of machines in a controlled manner. Motion control systems are extensively used in a variety of fields for automation purposes, including precision engineering, micromanufacturing, biotechnology, and nanotechnology. The main components involved typically include a motion controller, an energy amplifier, and one or more prime movers or actuators. Motion control may be open loop or closed loop. In open loop systems, the controller sends a command through the amplifier to the prime mover or actuator, and does not know if the desired motion was actually achieved. Typical systems include stepper motor or fan control. For tighter control with more precision, a measuring device may be added to the system (usually near the end motion). When the measurement is converted to a signal that is sent back to the controller, and the controller compensates for any error, it becomes a Closed loop System.\nTypically the position or velocity of machines are controlled using some type of device such as a hydraulic pump, linear actuator, or electric motor, generally a servo. Motion control is an important part of robotics and CNC machine tools, however in these instances it is more complex than when used with specialized machines, where the kinematics are usually simpler. The latter is often called General Motion Control (GMC). Motion control is widely used in the packaging, printing, textile, semiconductor production, and assembly industries.\nMotion Control encompasses every technology related to the movement of objects. It covers every motion system from micro-sized systems such as silicon-type micro induction actuators to micro-siml systems such as a space platform. But, these days, the focus of motion control is the special control technology of motion systems with electric actuators such as dc/ac servo motors. Control of robotic manipulators is also included in the field of motion control because most of robotic manipulators are driven by electrical servo motors and the key objective is the control of motion.\nOverview.\nThe basic architecture of a motion control system contains:\nThe interface between the motion controller and drives it control is very critical when coordinated motion is required, as it must provide tight synchronization. Historically the only open interface was an analog signal, until open interfaces were developed that satisfied the requirements of coordinated motion control, the first being SERCOS in 1991 which is now enhanced to SERCOS III. Later interfaces capable of motion control include Ethernet/IP, Profinet IRT, Ethernet Powerlink, and EtherCAT.\nCommon control functions include:", "Engineering,_Manufacturing": 0.9998139739, "qwen": "Yes"}
{"id": "65829281", "revid": "41591971", "url": "https://en.wikipedia.org/wiki?curid=65829281", "title": "Micro injection molding", "text": "Micro injection molding is a molding process for the manufacture of plastics components for shot weights of 1 to 0.1 grams with tolerances in the range of 10 to 100 microns. This molding process permits the manufacture of complicated small geometries with maximum possible accuracy and precision.\nBasic concept.\nThe basic concept of the micro injection molding process is quite similar to the regular injection molding process. In this process, a micro injection unit is integrated in the injection molding machine. When it comes to the production of micro components the machine and process technology mainly depend on the below points:\nCritical factors.\nParting line issue.\nA parting line (PL) is the line of separation on the part where the two halves of the mold meet. The parting line matching for micro parts is a big issue. The interlocking features of mold cavity and core for precise mating are used to reduce such issues.\nDegating issue.\nAnother major critical factor of micro injection technology is that the smaller part size causes problems with degating (gate removal).\nSprue and runner size.\nRunner and sprue diameters are another concern. The total volume of the feed system (sprue, runners and gates) can exceed the volume of the parts by a factor of 100 or more.\nMaterials and applications for micro injection molding.\nThe most common polymers used in micro injection molding are reported in the table below: \nMachine used for micro injection molding.\nIn the 1980s, micro injection molding techniques utilized traditional injection molding, but no dedicated machines were available until the mid-1990s. Currently, commercial micro molding systems are produced from Milacron, Arburg, and Sumitomo Demag as micro injection units for regular machines. At the same time, Wittmann Battenfeld, Babyplast and Desma are manufacturers of dedicated micro injection molding machines.\nMilacron developed two types of micro injection units: \nArburg developed a micro injection molding machine with an 8 mm injection to ensure high degree of dosing precision. This type of machine is combined with a second screw, which is responsible for melting and homogenous mixing of the material.\nSumitomo Demag developed a customized micro molding injection unit suitable for micro parts weighing of 5 g to 0.1 g.\nApplications.\nMicro injection molding is widely applied for parts and devices in the medical, pharmaceutical, electronics, automotive, optical and other industries. In general, the medical micro injection molding market is the leading one, due to an increase in the usage of sophisticated micro components for endoscopic surgery, minimally invasive treatments, point-of-care testing and other advanced technology developments. Applications in other fields include parts for electric motors, micron-tolerance door components, thing-wall containers, etc.\nMarket prospects.\nThe miniaturization of automotive, medical, electronics, telecommunications devices is driving the need for micro molding of smaller components. The global polymer and thermoplastic micro molding market covering medical, automotive, electronics and telecommunications was valued at $308m in 2012. The micro injection molding plastic market was valued at $1,145.85 million in 2022 and is anticipated to reach $2,640 million by 2030, growing at a compound annual growth rate (CAGR) of 11.0% from 2023 to 2030. ", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "65838697", "revid": "4455963", "url": "https://en.wikipedia.org/wiki?curid=65838697", "title": "Light resin transfer moulding", "text": "Light resin transfer moulding (Light RTM) is a process by which products of Composite materials are manufactured using a closed mold system.\nProcedure.\nSimilar to the methods performed in resin transfer molding, Light RTM involves a closed mold process. A vacuum holds mold A and mold B together to result in two finished sides with fixed thickness levels. Vacuum rings around the tools hold the molds together for this process after dry fiber reinforcements are loaded into mold A before joining with mold B. \nThe air is vacuumed out of the molds with a lower vacuum level, separate from the tooling. After the air is removed the resin is injected into the part. The vacuum remains in effect into the resin is cured.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "65844973", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=65844973", "title": "Green supply chain management", "text": "Green supply chain management (GSCM) is the consideration of environmental issues in supply chain management. \nDefinitions and scope.\nGSCM has been defined as follows:\nSrivastava (2007) defines GSCM’s scope as ranging \"from reactive monitoring of general environmental management programs to more proactive practices implemented through various Rs (Reduce, Re-use, Rework, Refurbish, Reclaim, Recycle, Remanufacture, Reverse logistics, etc.).” From an entrepreneurial perspective, entrepreneurial GSCM is a new approach to environmental management executed by green entrepreneurs across whole supply chains instead of thinking in terms of individual non-environmental firms. This new holistic view can integrate individuals, companies, and supply-chains of different entrepreneurs from various countries together in an environmental friendly way.\nGSCM criteria.\nA nonexhaustive list of GSCM criteria from D. Kannan et al. (2014) is given below. \nRelative importance of criteria.\nInstead of concentrating equally on every criterion, more attention should be given to the most important criteria. D. Kannan et al. (2014) calculated the importance of criteria by taking the preferences of 3 decision-makers:\nIn this table, the preferences of criteria are given in terms of linguistic variables. From these linguistic variables, calculations were done to find out the ranking of the importance of criteria. \nForm the above graph; it is clear that the top 4 most important GSCM criteria are \nThis result was obtained when the authors considered the GSCM criteria for choosing a supplier for an electronics company in Brazil (a developing country). Depending on the situation, it is possible that other GSCM criteria are deemed to be more important by the decision-makers. (For example, if the same research were done in a developed country instead of a developing country, other criteria might have received a higher ranking).\nBarriers.\nTumpa et al., 2019 conducted a study to find the hurdles faced while implementing GSCM practices. The study was conducted in the textile industry of Bangladesh (a developing country). Some of the most important hurdles were found out to be\nOther hurdles may be more important in different situations (Example – if the study were done in a developed country instead of a developing country)\nAnother considerable hurdle for firms trying to implement GSCM practices is the fact that many suppliers along the complete supply chain reside outside of any direct organizational control from the firm. Supply chains are often built upon a network of individual suppliers and a firm's ability to meet their Corporate Sustainability Standards can be hindered by suppliers with which they do not directly interact. ", "Engineering,_Manufacturing": 0.9981848001, "qwen": "Yes"}
{"id": "8978415", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=8978415", "title": "Cryogenic treatment", "text": "A cryogenic treatment is the process of treating workpieces to cryogenic temperatures (typically around -300°F / -184°C, or as low as ) in order to remove residual stresses and improve wear resistance in steels and other metal alloys, such as aluminum. In addition to seeking enhanced stress relief and stabilization, or wear resistance, cryogenic treatment is also sought for its ability to improve corrosion resistance by precipitating micro-fine eta carbides, which can be measured before and after in a part using a quantimet.\nThe process has a wide range of applications from industrial tooling to the improvement of musical signal transmission. Some of the benefits of cryogenic treatment include longer part life, less failure due to cracking, improved thermal properties, better electrical properties including less electrical resistance, reduced coefficient of friction, less creep and walk, improved flatness, and easier machining.\nProcesses.\nCryogenic tempering.\nCryogenic tempering is two phase metal treatment that involves a descent and ascent phase, including a cryogenic treatment process (known as \"cryogenic processing\") where the material is slowly cooled to ultra low temperatures (typically around -300°F / -184°C), which is then optionally reheated slowly (typically up to +325°F / 162°C). Materials do not \"harden\" during the temperature descent or ascent, rather their molecular structures are compressed together tightly in uniformity through a computer controlled process that typically uses liquid nitrogen to slowly descend temperatures.\nInvention History of Cryogenic Processing & Cryogenic Tempering.\nThe cryogenic treatment process was invented by Ed Busch (CryoTech) in Detroit, Michigan in 1966, inspired by NASA research, which later merged with 300 Below, Inc. in 2000 to become the world's largest and oldest commercial cryogenic processing company after Peter Paulin of Decatur, IL collaborated with process control engineers to invent the world's first computer-controlled \"dry\" cryogenic processor in 1992 (where he was featured on the Discovery Channel's Next Step TV Show for his invention). Whereas the industry initially submerged metal parts in liquid nitrogen by dunking them or pouring liquid nitrogen over the parts, the earliest results proved inconsistent, which led Mr. Paulin to develop 300 Below's \"dry\" computer-controlled cryogenic processing equipment to ensure consistent and accurate treatment results across every processing run by introducing liquid nitrogen into a chamber above its boiling point, in a \"dry\" gaseous state, to ensure that parts in a chamber are not thermally shocked from being exposed to direct liquid contact of ultra low temperatures. A \"dry\" cryogenic process does not submerge parts in liquid, but rather ensures that temperatures are slowly descended at less than one degree per minute using short bursts of cold gas being introduced via a solenoid-metered pipe, which is controlled by a computer equipment paired with highly accurate RTD (Resistance Temperature Detector) sensors.\nScience Behind Dry Cryogenic Processing & Cryogenic Tempering.\nBecause all changes to metals take place on the quench, the first phase of the initial descent is called cryogenic processing, and by adding a second phase to heat the molecular structure of materials after an initial molecular re-alignment, both processes together are called cryogenic tempering. By using liquid nitrogen, the temperature can go as low as −196 °C, though the typical dwell temperature of cryogenic processing equipment is slightly above the boiling point of liquid nitrogen (closer to -300°F / -184°C) due to being injected into the processing chamber as a gaseous state and making every attempt not to introduce liquid into the chamber that could cause parts to become thermally shocked. Cryogenic processing (and especially cryogenic tempering) can have a profound effect on the mechanical properties of certain materials, such as steels or tungsten carbide, but the heating phase in cryogenic tempering is typically omitted for softer metals like brass in musical instruments, for piano strings, in certain aerospace applications, or for sensitive electronic components like vacuum tubes and transistors in high-end audio equipment. In tungsten carbide (WC-Co), the crystal structure of cobalt is transformed from softer FCC to harder HCP phase whereas the hard tungsten carbide particle is unaffected by the treatment.\nCryogenic machining.\nCryogenic machining is a machining process where the traditional flood lubro-cooling liquid (an emulsion of oil into water) is replaced by a jet of either liquid nitrogen (LN2) or pre-compressed carbon dioxide . Cryogenic machining is useful in rough machining operations, in order to increase the tool life. It can also be useful to preserve the integrity and quality of the machined surfaces in finish machining operations. Cryogenic machining tests have been performed by researchers for several decades, but the actual commercial applications are still limited to very few companies. Both cryogenic machining by turning and milling are possible. Cryogenic machining is a relatively new technique in machining. This concept was applied on various machining processes such as turning, milling, drilling etc. Cryogenic turning technique is generally applied on three major groups of workpiece materials—superalloys, ferrous metals, and viscoelastic polymers/elastomers. The roles of cryogen in machining different materials are unique.\nCryogenic rolling.\nCryogenic rolling or \"\", is one of the potential techniques to produce nanostructured bulk materials from its bulk counterpart at cryogenic temperatures. It can be defined as rolling that is carried out at cryogenic temperatures. Nanostructured materials are produced chiefly by severe plastic deformation processes. The majority of these methods require large plastic deformations (strains much larger than unity). In case of cryorolling, the deformation in the strain hardened metals is preserved as a result of the suppression of the dynamic recovery. Hence large strains can be maintained and after subsequent annealing, ultra-fine-grained structure can be produced.\nAdvantages.\nComparison of cryorolling and rolling at room temperature:\nCryogenic treatment in specific materials.\nStainless steel.\nThe torsional and tensional deformation under cryogenic temperature of stainless steel is found to be significantly enhance the mechanical strength while incorporating the gradual phase transformation inside the steel. This strength improvement is the result of following phenomenon.\nCopper.\nZhang et al. exploited the cryorolling to the dynamic plastic deformed copper at liquid nitrogen temperature (LNT-DPD) to greatly enhance tensile strength with high ductility. The key of this combined approach (Cryogenic hardening and Cryogenic rolling) is to engineer the nano-sized twin boundary embedded in the copper. \nProcessing with the plastic deformation of grained bulk metal decreases the size of the grain boundary and enhances the grain boundary strengthening. However, as the grain gets smaller, the interaction between grain and the dislocation inside impedes further process of grains. Among the grain boundaries, it is known that the twin boundaries, a special type of low-energy grain boundary has lower interaction energy with dislocation leading to much smaller saturation size of the grain.\nThe cryogenic dynamic plastic deformation creates higher fraction of the twin boundaries compared to the severe plastic deformation. Following cryorolling further reduces the grain boundary energy with relieving the twin boundary leading to higher Hall-Petch strengthening effect. In addition, this increases the ability of grain boundary to accommodate more dislocation leading to the improvement in ductility from cryorolling.\nTitanium.\nCryogenic hardening of Titanium is hard to manipulate compare to other face centered cubic (fcc) metals because these hexagonal close packed (hcp) metals has less symmetry and slip systems to exploit. Recently Zhao et al. introduced the efficient method to manipulate nanotwinned titanium which has higher strength, ductility and thermal stability. By cryoforging repetitively along the three principal axes in liquid nitrogen and following annealing process, pure Titanium can possess hierarchical twin boundary network structure which suppresses the motion of dislocation and significantly enhances its mechanical property. The microstructure analysis found that the repeated twinning and de-twinning keep increasing the fraction of nanosized twin boundaries and refining the grains to render much higher Hall-Petch strengthening effect even after the saturation of microscale twin boundary at high flow stress. Especially, the strength and ductility of nanotwinned titanium at 77 K, reaches about 2 GPa, and ~100% which far outweighs those of conventional cryogenic steels even without any inclusion of alloying.", "Engineering,_Manufacturing": 0.9999867678, "qwen": "Yes"}
{"id": "231291", "revid": "15412317", "url": "https://en.wikipedia.org/wiki?curid=231291", "title": "Ball grid array", "text": "A ball grid array (BGA) is a type of surface-mount packaging (a chip carrier) used for integrated circuits. BGA packages are used to permanently mount devices such as microprocessors. A BGA can provide more interconnection pins than can be put on a dual in-line or flat package. The whole bottom surface of the device can be used, instead of just the perimeter. The traces connecting the package's leads to the wires or balls which connect the die to package are also on average shorter than with a perimeter-only type, leading to better performance at high speeds.\nBGAs were introduced in the 1990s and became popular by 2001.\nSoldering of BGA devices requires precise control and is usually done by automated processes such as in computer-controlled automatic reflow ovens.\nDescription.\nThe BGA is descended from the pin grid array (PGA), which is a package with one face covered (or partly covered) with pins in a grid pattern which, in operation, conduct electrical signals between the integrated circuit and the printed circuit board (PCB) on which it is placed. In a BGA the pins are replaced by pads on the bottom of the package, each initially with a tiny solder ball stuck to it. These solder spheres can be placed manually or by automated equipment, and are held in place with a tacky flux. The device is placed on a PCB with copper pads in a pattern that matches the solder balls. The assembly is then heated, either in a reflow oven or by an infrared heater, melting the balls. Surface tension causes the molten solder to hold the package in alignment with the circuit board, at the correct separation distance, while the solder cools and solidifies, forming soldered connections between the device and the PCB.\nIn more advanced technologies, solder balls may be used on both the PCB and the package. Also, in stacked multi-chip modules, (package on package) solder balls are used to connect two packages.\nAdvantages.\nHigh density.\nThe BGA is a solution to the problem of producing a miniature package for an integrated circuit with many hundreds of pins. Pin grid arrays and dual-in-line surface mount (SOIC) packages were being produced with more and more pins, and with decreasing spacing between the pins, but this was causing difficulties for the soldering process. As package pins got closer together, the danger of accidentally bridging adjacent pins with solder grew.\nHeat conduction.\nA further advantage of BGA packages over packages with discrete leads (i.e. packages with legs) is the lower thermal resistance between the package and the PCB. This allows heat generated by the integrated circuit inside the package to flow more easily to the PCB, preventing the chip from overheating.\nLow-inductance leads.\nThe shorter an electrical conductor, the lower its unwanted inductance, a property which causes unwanted distortion of signals in high-speed electronic circuits. BGAs, with their very short distance between the package and the PCB, have low lead inductances, giving them superior electrical performance to pinned devices.\nDisadvantages.\nLack of compliance.\nA disadvantage of BGAs is that the solder balls cannot flex in the way that longer leads can, so they are not mechanically compliant. As with all surface mount devices, bending due to a difference in coefficient of thermal expansion between PCB substrate and BGA (thermal stress) or flexing and vibration (mechanical stress) can cause the solder joints to fracture.\nThermal expansion issues can be overcome by matching the mechanical and thermal characteristics of the PCB to those of the package. Typically, plastic BGA devices more closely match PCB thermal characteristics than ceramic devices.\nThe predominant use of RoHS compliant lead-free solder alloy assemblies has presented some further challenges to BGAs including \"head in pillow\" soldering phenomenon, \"pad cratering\" problems as well as their decreased reliability versus lead-based solder BGAs in extreme operating conditions such as high temperature, high thermal shock and high gravitational force environments, in part due to lower ductility of RoHS-compliant solders.\nMechanical stress issues can be overcome by bonding the devices to the board through a process called \"underfilling\", which injects an epoxy mixture under the device after it is soldered to the PCB, effectively gluing the BGA device to the PCB. There are several types of underfill materials in use with differing properties relative to workability and thermal transfer. An additional advantage of underfill is that it limits tin whisker growth.\nAnother solution to non-compliant connections is to put a \"compliant layer\" in the package that allows the balls to physically move in relation to the package. This technique has become standard for packaging DRAMs in BGA packages.\nOther techniques for increasing the board-level reliability of packages include use of low-expansion PCBs for ceramic BGA (CBGA) packages, interposers between the package and PCB, and re-packaging a device.\nDifficulty of inspection.\nOnce the package is soldered into place, it is difficult to find soldering faults. X-ray machines, industrial CT scanning machines, special microscopes, and endoscopes to look underneath the soldered package have been developed to overcome this problem. If a BGA is found to be badly soldered, it can be removed in a \"rework station\", which is a jig fitted with infrared lamp (or hot air), a thermocouple and a vacuum device for lifting the package. The BGA can be replaced with a new one, or it can be refurbished (or \"reballed\") and re-installed on the circuit board. Pre-configured solder balls matching the array pattern can be used to reball BGAs when only one or a few need to be reworked. For higher volume and repeated lab work, a stencil-configured vacuum-head pick-up and placement of loose spheres can be used.\nDue to the cost of visual X-ray BGA inspection, electrical testing is very often used instead. Very common is boundary scan testing using an IEEE 1149.1 JTAG port.\nA cheaper and easier inspection method, albeit destructive, is becoming increasingly popular because it does not require special equipment. Commonly referred to as dye and pry, the process includes immersing the entire PCB or just the BGA attached module into a dye, and after drying, the module is pried off and the broken joins are inspected. If a solder location contains the dye, then it indicates that the connection was imperfect.\nDifficulties during circuit development.\nDuring development it is not practical to solder BGAs into place, and sockets are used instead, but tend to be unreliable. There are two common types of socket: the more reliable type has spring pins that push up under the balls, although it does not allow using BGAs with the balls removed as the spring pins may be too short.\nThe less reliable type is a ZIF socket, with spring pinchers that grab the balls. This does not work well, especially if the balls are small.\nCost of equipment.\nExpensive equipment is required to reliably solder BGA packages; hand-soldering BGA packages is very difficult and unreliable, usable only for the smallest packages in the smallest quantities. However, as more ICs have become available only in leadless (e.g. quad-flat no-leads package) or BGA packages, various DIY reflow methods have been developed using inexpensive heat sources such as heat guns, and domestic toaster ovens and electric skillets.\nVariants.\nEffectively also the flip chip methods for mounting chip dies to a carrier is sort of a BGA design derivate with the functional equivalent of the balls there being called bumps or micro bumps. This is realized at an already microscopic size level.\nTo make it easier to use ball grid array devices, most BGA packages only have balls in the outer rings of the package,\nleaving the innermost square empty.\nIntel used a package designated BGA1 for their Pentium II and early Celeron mobile processors. BGA2 is Intel's package for their Pentium III and some later Celeron mobile processors. BGA2 is also known as FCBGA-479. It replaced its predecessor, BGA1.\nFor example, the \"micro-FCBGA\" (flip chip ball grid array) is Intel's current BGA mounting method for mobile processors that use a flip chip binding technology. It was introduced with the \"Coppermine\" Mobile Celeron. Micro-FCBGA has 479 balls that are 0.78 mm in diameter. The processor is affixed to the motherboard by soldering the balls to the motherboard. This is thinner than a pin grid array socket arrangement, but is not removable.\nThe 479 balls of the Micro-FCBGA package (a package almost identical to the 478-pin socketable micro-FCPGA package) are arranged as the 6 outer rings of a 1.27 mm pitch (20 balls per inch pitch) 26x26 square grid, with the inner 14x14 region empty.\nProcurement.\nPrimary end-users of BGAs are original equipment manufacturers (OEMs). There is also a market among electronic hobbyists do it yourself (DIY) such as the increasingly popular maker movement. While OEMs generally source their components from the manufacturer, or the manufacturer's distributor, the hobbyist will typically obtain BGAs on the aftermarket through electronic component brokers or .", "Engineering,_Manufacturing": 0.9999656677, "qwen": "Yes"}
{"id": "232333", "revid": "44120587", "url": "https://en.wikipedia.org/wiki?curid=232333", "title": "Surface-mount technology", "text": "Surface-mount technology (SMT), originally called planar mounting, is a method in which the electrical components are mounted directly onto the surface of a printed circuit board (PCB). An electrical component mounted in this manner is referred to as a surface-mount device (SMD). In industry, this approach has largely replaced the through-hole technology construction method of fitting components, in large part because SMT allows for increased manufacturing automation which reduces cost and improves quality. It also allows for more components to fit on a given area of substrate. Both technologies can be used on the same board, with the through-hole technology often used for components not suitable for surface mounting such as large transformers and heat-sinked power semiconductors.\nAn SMT component is usually smaller than its through-hole counterpart because it has either smaller leads or no leads at all. It may have short pins or leads of various styles, flat contacts, a matrix of solder balls (BGAs), or terminations on the body of the component.\nHistory.\nSurface-mount technology was developed in the 1960s. By 1986 surface mounted components accounted for 10% of the market at most, but was rapidly gaining popularity. By the late 1990s, the great majority of high-tech electronic printed circuit assemblies were dominated by surface mount devices. Much of the pioneering work in this technology was done by IBM. The design approach first demonstrated by IBM in 1960 in a small-scale computer was later applied in the Launch Vehicle Digital Computer used in the Instrument Unit that guided all Saturn IB and Saturn V vehicles. Components were mechanically redesigned to have small metal tabs or end caps that could be directly soldered to the surface of the PCB. Components became much smaller and component placement on both sides of a board became far more common with surface mounting than through-hole mounting, allowing much higher circuit densities and smaller circuit boards and, in turn, machines or subassemblies containing the boards.\nOften the surface tension of the solder is enough to hold the parts to the board; in rare cases parts on the bottom or \"second\" side of the board may be secured with a dot of adhesive to keep components from dropping off inside reflow ovens if the part is above the limit of 30g per square inch of pad area. Adhesive is sometimes used to hold SMT components on the bottom side of a board if a wave soldering process is used to solder both SMT and through-hole components simultaneously. Alternatively, SMT and through-hole components can be soldered on the same side of a board without adhesive if the SMT parts are first reflow-soldered, then a selective solder mask is used to prevent the solder holding those parts in place from reflowing and the parts floating away during wave soldering. Surface mounting lends itself well to a high degree of automation, reducing labor cost and greatly increasing production rates.\nConversely, SMT does not lend itself well to manual or low-automation fabrication, which is more economical and faster for one-off prototyping and small-scale production, and this is one reason why many through-hole components are still manufactured. Some SMDs can be soldered with a temperature-controlled manual soldering iron, but unfortunately, those that are very small or have too fine a lead pitch are impossible to manually solder without expensive hot-air solder reflow equipment. SMDs can be one-quarter to one-tenth the size and weight, and one-half to one-quarter the cost of equivalent through-hole parts, but on the other hand, the costs of a certain SMT part and of an equivalent through-hole part may be quite similar, though rarely is the SMT part more expensive.\nCommon abbreviations.\nDifferent terms describe the components, technique, and machines used in manufacturing. These terms are listed in the following table:\nAssembly techniques.\nWhere components are to be placed, the printed circuit board normally has flat, usually tin-lead, silver, or gold plated copper pads without holes, called \"solder pads\". Solder paste, a sticky mixture of flux and tiny solder particles, is first applied to all the solder pads with a stainless steel or nickel stencil using a screen printing process. It can also be applied by a jet-printing mechanism, similar to an inkjet printer. After pasting, the boards proceed to the pick-and-place machines, where they are placed on a conveyor belt. The components to be placed on the boards are usually delivered to the production line in either paper/plastic tapes wound on reels or plastic tubes. Some large integrated circuits are delivered in static-free trays. Numerical control pick-and-place machines remove the parts from the tapes, tubes or trays and place them on the PCB.\nThe boards are then conveyed into the reflow soldering oven. They first enter a pre-heat zone, where the temperature of the board and all the components is gradually, uniformly raised to prevent thermal shock. The boards then enter a zone where the temperature is high enough to melt the solder particles in the solder paste, bonding the component leads to the pads on the circuit board. The surface tension of the molten solder helps keep the components in place, and if the solder pad geometries are correctly designed, surface tension automatically aligns the components on their pads.\nThere are a number of \"techniques\" for reflowing solder. One is to use infrared lamps; this is called infrared reflow. Another is to use a hot gas convection. Another technology which is becoming popular again is special fluorocarbon liquids with high boiling points which use a method called vapor phase reflow. Due to environmental concerns, this method was falling out of favor until lead-free legislation was introduced which requires tighter controls on soldering. At the end of 2008, convection soldering was the most popular reflow technology using either standard air or nitrogen gas. Each method has its advantages and disadvantages. With infrared reflow, the board designer must lay the board out so that short components do not fall into the shadows of tall components. Component location is less restricted if the designer knows that vapor phase reflow or convection soldering will be used in production. Following reflow soldering, certain irregular or heat-sensitive components may be installed and soldered by hand, or in large-scale automation, by focused infrared beam (FIB) or localized convection equipment.\nIf the circuit board is double-sided then this printing, placement, reflow process may be repeated using either solder paste or glue to hold the components in place. If a wave soldering process is used, then the parts must be glued to the board prior to processing to prevent them from floating off when the solder paste holding them in place is melted.\nAfter soldering, the boards may be washed to remove flux residues and any stray solder balls that could short out closely spaced component leads. Rosin flux is removed with fluorocarbon solvents, high flash point hydrocarbon solvents, or low flash solvents e.g. limonene (derived from orange peels) which require extra rinsing or drying cycles. Water-soluble fluxes are removed with deionized water and detergent, followed by an air blast to quickly remove residual water. However, most electronic assemblies are made using a \"No-Clean\" process where the flux residues are designed to be left on the circuit board, since they are considered harmless. This saves the cost of cleaning, speeds up the manufacturing process, and reduces waste. However, it is generally suggested to wash the assembly, even when a \"No-Clean\" process is used, when the application uses very high frequency clock signals (in excess of 1 GHz). Another reason to remove no-clean residues is to improve adhesion of conformal coatings and underfill materials. Regardless of cleaning or not those PCBs, current industry trend suggests to carefully review a PCB assembly process where \"No-Clean\" is applied, since flux residues trapped under components and RF shields may affect surface insulation resistance (SIR), especially on high component density boards.\nCertain manufacturing standards, such as those written by the IPC - Association Connecting Electronics Industries require cleaning regardless of the solder flux type used to ensure a thoroughly clean board. Proper cleaning removes all traces of solder flux, as well as dirt and other contaminants that may be invisible to the naked eye. No-Clean or other soldering processes may leave \"white residues\" that, according to IPC, are acceptable \"provided that these residues have been qualified and documented as benign\". However, while shops conforming to IPC standard are expected to adhere to the Association's rules on board condition, not all manufacturing facilities apply IPC standard, nor are they required to do so. Additionally, in some applications, such as low-end electronics, such stringent manufacturing methods are excessive both in expense and time required.\nFinally, the boards are visually inspected for missing or misaligned components and solder bridging. If needed, they are sent to a rework station where a human operator repairs any errors. They are then usually sent to the testing stations (in-circuit testing and/or functional testing) to verify that they operate correctly.\nAutomated optical inspection (AOI) systems are commonly used in PCB manufacturing. This technology has proven highly efficient for process improvements and quality achievements.\nAdvantages.\nThe main advantages of SMT over the older through-hole technique are:\nRework.\nDefective surface-mount components can be repaired by using soldering irons (for some connections), or using a non-contact rework system. In most cases a rework system is the better choice because SMD work with a soldering iron requires considerable skill and is not always feasible.\nReworking usually corrects some type of error, either human- or machine-generated, and includes the following steps:\nSometimes hundreds or thousands of the same part need to be repaired. Such errors, if due to assembly, are often caught during the process. However, a whole new level of rework arises when component failure is discovered too late, and perhaps unnoticed until the end user of the device being manufactured experiences it. Rework can also be used if products of sufficient value to justify it require revision or re-engineering, perhaps to change a single firmware-based component. Reworking in large volume requires an operation designed for that purpose.\nThere are essentially two non-contact soldering/desoldering methods: infrared soldering and soldering with hot gas.\nInfrared.\nWith infrared soldering, the energy for heating up the solder joint is transmitted by long-, medium- or short-wave infrared electromagnetic radiation.\nAdvantages:\nDisadvantages:\nHot gas.\nDuring hot gas soldering, the energy for heating up the solder joint is transmitted by a hot gas. This can be air or inert gas (nitrogen).\nAdvantages:\nDisadvantages:\nHybrid technology.\nHybrid rework systems combine medium-wave infrared radiation with hot air\nAdvantages:\nDisadvantages\nPackages.\nSurface-mount components are usually smaller than their counterparts with leads, and are designed to be handled by machines rather than by humans. The electronics industry has standardized package shapes and sizes (the leading standardisation body is JEDEC).", "Engineering,_Manufacturing": 0.9999884367, "qwen": "Yes"}
{"id": "233017", "revid": "43905122", "url": "https://en.wikipedia.org/wiki?curid=233017", "title": "Pin grid array", "text": "A pin grid array (PGA) is a type of integrated circuit packaging. In a PGA, the package is square or rectangular, and the pins are arranged in a regular array on the underside of the package. The pins are commonly spaced 2.54 mm (0.1\") apart, and may or may not cover the entire underside of the package.\nPGAs are often mounted on printed circuit boards using the through hole method or inserted into a socket. PGAs allow for more pins per integrated circuit than older packages, such as dual in-line package (DIP).\nChip mounting.\nThe chip can be mounted either on the top or the bottom (the pinned side). Connections can be made either by wire bonding or through flip chip mounting. Typically, PGA packages use wire bonding when the chip is mounted on the pinned side, and flip chip construction when the chip is on the top side. Some PGA packages contain multiple dies, for example Zen 2 and Zen 3 Ryzen CPUs for the AM4 socket.\nFlip chip.\nA flip-chip pin grid array (FC-PGA or FCPGA) is a form of pin grid array in which the die faces downwards on the top of the substrate with the back of the die exposed. This allows the die to have a more direct contact with the heatsink or other cooling mechanism.\nThe FC-PGA was introduced by Intel with the Coppermine core Pentium III and Celeron processors based on Socket 370, and was later used for Socket 478-based Pentium 4 and Celeron processors. FC-PGA processors fit into zero insertion force (ZIF) Socket 370 and Socket 478-based motherboard sockets; similar packages have also been used by AMD. It is still used today for mobile Intel processors.\nMaterial.\nCeramic.\nA ceramic pin grid array (CPGA) is a type of packaging used by integrated circuits. This type of packaging uses a ceramic substrate with pins arranged in a pin grid array. Some CPUs that use CPGA packaging are the AMD Socket A Athlons and the Duron.\nA CPGA was used by AMD for Athlon and Duron processors based on Socket A, as well as some AMD processors based on Socket AM2 and Socket AM2+. While similar form factors have been used by other manufacturers, they are not officially referred to as CPGA. This type of packaging uses a ceramic substrate with pins arranged in an array.\nOrganic.\nAn organic pin grid array (OPGA) is a type of connection for integrated circuits, and especially CPUs, where the silicon die is attached to a plate made out of an organic plastic which is pierced by an array of pins which make the requisite connections to the socket.\nPlastic.\nPlastic pin grid array (PPGA) packaging was used by Intel for late-model Mendocino core Celeron processors based on Socket 370. Some pre-Socket 8 processors also used a similar form factor, although they were not officially referred to as PPGA.\nPin layout.\nStaggered pin.\nThe staggered pin grid array (SPGA) is used by Intel processors based on Socket 5 and Socket 7. Socket 8 used a partial SPGA layout on half the processor.\nIt consists of two square arrays of pins, offset in both directions by half the minimum distance between pins in one of the arrays. Put differently: within a square boundary the pins form a diagonal square lattice. There is generally a section in the center of the package without any pins. SPGA packages are usually used by devices that require a higher pin density than what a PGA can provide, such as microprocessors.\nStud.\nA stud grid array (SGA) is a short-pinned pin grid array chip scale package for use in surface-mount technology. The polymer stud grid array or plastic stud grid array was developed jointly by the Interuniversity Microelectronics Centre (IMEC) and Laboratory for Production Technology, Siemens AG.\nrPGA.\nThe reduced pin grid array was used by the socketed mobile variants of Intel's Core i3/5/7 processors and features a reduced pin pitch of 1mm, as opposed to the 1.27mm pin pitch used by contemporary AMD processors and older Intel processors. It is used in the G1, G2, and G3 sockets.", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "233019", "revid": "1151557336", "url": "https://en.wikipedia.org/wiki?curid=233019", "title": "Zig-zag in-line package", "text": "The zig-zag in-line package (ZIP) is a packaging technology for integrated circuits. It was intended as a replacement for dual in-line packaging (DIL or DIP). A ZIP is an integrated circuit encapsulated in a slab of plastic with 16, 20, 28 or 40 pins, measuring (for the ZIP-20 package) about 3 mm x 30 mm x 10 mm. The package's pins protrude in two rows from one of the long edges. The two rows are staggered by 1.27 mm (0.05\"), giving them a zig-zag appearance, and allowing them to be spaced more closely than a rectangular grid would allow. The pins are inserted into holes in a printed circuit board, with the packages standing at right-angles to the board, allowing them to be placed closer together than DIPs of the same size. ZIPs have now been superseded by surface-mount packages such as the thin small-outline packages (TSOPs), but are still in use. The quad in-line package uses a similar staggered semiconductor package design.\nHigh-power devices (such as high-voltage op-amp ICs, voltage regulators, and motor driver ICs) are still being manufactured in a package with a zig-zag pinout (and normally screwed onto a heatsink). These zig-zag packages include variations on the TO220 such as \"TO220S\", \"staggered leads TO-220-11\", \"staggered leads TO-220-15\", and HZIP. The trademarks Pentawatt or Hexawatt are also used for chips in multi-leaded power packages like TDA2002/2003/2020/2030 and L200.\nAs for computers, dynamic RAM ZIP chips are now only to be found in obsolete computers, some of these are:", "Engineering,_Manufacturing": 1.0000071526, "qwen": "Yes"}
{"id": "7836846", "revid": "1166336624", "url": "https://en.wikipedia.org/wiki?curid=7836846", "title": "Model maker", "text": "A Model maker is a professional Craftsperson who creates a three-dimensional representation of a design or concept. Most products in use and in development today first take form as a model. This \"model\" may be an exacting duplicate (prototype) of the future design or a simple mock-up of the general shape or concept. Many prototype models are used for testing physical properties of the design, others for usability and marketing studies. \nMock-ups are generally used as part of the design process to help convey each new iteration. Some model makers specialize in \"scale models\" that allow an easier grasp of the whole design or for portability of the model to a trade show or an architect or client's office. Other scale models are used in museum displays and in the movie special effects industry. Model makers work in many environments from private studio/shops to corporate design and engineering facilities to research laboratories.\nThe model maker must be highly skilled in the use of many machines, such as manual lathes, manual mills, Computer Numeric Control (CNC) machines, lasers, wire EDM, water jet saws, tig welders, sheet metal fabrication tools and wood working tools. Fabrication processes model makers take part in are powder coating, shearing, punching, plating, folding, forming and anodizing. Some model makers also use increasingly automated processes, for example cutting parts directly with digital data from computer-aided design plans on a CNC mill or creating the parts through rapid prototyping. Hand tools used by a model maker are an exacto knife, tweezers, sprue cutter, tape, glue, paint, and paint brushes.\nThere are two basic processes used by the model maker to create models: additive and subtractive. Additive can be as simple as adding clay to create a form, sculpting and smoothing to the final shape. Body fillers, foam and resins are also used in the same manner. Most rapid prototyping technologies are based on the additive process, solidifying thin layered sections or slices one on top of each other. Subtractive is like whittling a solid block of wood or chiseling stone to the desired form. Most milling and other machining methods are subtractive, progressively using smaller and finer tools to remove material from the rough shape to get to the level of detail needed in the final model. \nModel makers may use a combination of these methods and technologies to create the model in the most expeditious manner. The parts are usually test fitted, then sanded and painted to represent the intended finish or look. Model makers are required to recreate many faux finishes like brick, stone, grass, molded plastic textures, glass, skin and even water.", "Engineering,_Manufacturing": 1.0000077486, "qwen": "Yes"}
{"id": "7841263", "revid": "44120587", "url": "https://en.wikipedia.org/wiki?curid=7841263", "title": "Abrasive flow machining", "text": "Abrasive flow machining (AFM), also known as abrasive flow deburring or extrude honing, is an interior surface finishing process characterized by flowing an abrasive-laden fluid through a workpiece. This fluid is typically very viscous, having the consistency of putty, or dough. AFM smooths and finishes rough surfaces, and is specifically used to remove burrs, polish surfaces, form radii, and even remove material. The nature of AFM makes it ideal for interior surfaces, slots, holes, cavities, and other areas that may be difficult to reach with other polishing or grinding processes. Due to its low material removal rate, AFM is not typically used for large stock-removal operations, although it can be.\nAbrasive flow machining was first patented by the Extrude Hone Corporation in 1970.\nProcess.\nIn abrasive flow machining, the abrasive fluid flows through the workpiece, effectively performing erosion. Abrasive particles in the fluid contact raised features on the surface of the workpiece and remove them. The fluid is forced through the workpiece by a hydraulic ram, where it acts as a flexible file, or slug, molding itself precisely to the shape of the workpiece. The highest amount of material removal occurs in areas where the flow of the fluid is restricted; according to Bernoulli's Principle, the flow speed and pressure of the fluid decrease in these areas, facilitating a higher material removal rate (MRR). The pressure exerted by the fluid on all contacting surfaces also results in a very uniform finish.\nAFM may be performed once, as a one-way flow process, or repeatedly as a two-way flow process. In the two-way flow process, a reservoir of medium exists at either end of the workpiece, and the medium flows back and forth through the workpiece from reservoir to reservoir.\nEquipment.\nAn abrasive flow machine normally includes two medium chambers equipped with hydraulic rams, a fixture for holding the workpiece, and a clamping system that holds all the components tightly together. Most machines allow for the loading of different types of abrasive medium, and include the capacity to adjust the pressure used in extruding the medium through the workpiece. They may be manually operated, or automated using CNC. For machines designed to accommodate high production volumes, accessories such as part-cleaning stations, unloading and reloading stations, media refeed devices, and media heat exchangers may be included.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "49976857", "revid": "37843727", "url": "https://en.wikipedia.org/wiki?curid=49976857", "title": "Tardiness (scheduling)", "text": "In scheduling, tardiness is a measure of a delay in executing certain operations and earliness is a measure of finishing operations before due time. The operations may depend on each other and on the availability of equipment to perform them.\nTypical examples include job scheduling in manufacturing and data delivery scheduling in data processing networks.\nIn manufacturing environment, inventory management considers both tardiness and earliness undesirable. Tardiness involves backlog issues such as customer compensation for delays and loss of goodwill. Earliness incurs expenses for storage of the manufactured items and ties up capital.\nMathematical formulations.\nIn an environment with multiple jobs, let the deadline be formula_1 and the completion time be formula_2 of job formula_3. Then for job formula_3\nIn scheduling common objective functions are formula_8 or weighted version of these sums, formula_9, where every job comes with a weight formula_10. The weight is a representation of job cost, priority, etc.\nIn a large number of cases the problems of optimizing these functions are NP-hard.", "Engineering,_Manufacturing": 0.999635458, "qwen": "Yes"}
{"id": "49987432", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=49987432", "title": "Metal stitching", "text": "Metal stitching is an industrial technique for repairing cracked and broken cast iron, steel, bronze or aluminium structures and their components. The process is carried out cold, without welding. It allows the repair of cast iron and cast steel, often in-situ, without the distortion from welding, and can be used in other situations where heat cannot be used to achieve a repair.\nBackground.\nThe metal stitching process was developed in the late 1930s as an option for repairing cast iron components and equipment on the Texas oil fields. The process was developed to provide a permanent, stress-free repair and utilized when the use of heat or open flame was limited or not allowed. Four men have been credited with the development of this new metal locking technique: Lawrence B. Scott, Fred Lewis, Earl Reynolds and Hal W. Harman. However, it was Hal Harman who initially invented the metal stitching technique, and he filed for a patent to the technique in the 7th of August, 1937.\nIn 1938 L.B. Scott was officially credited with the invention of the Metalock variation of metal stitching, whilst he was still working for Harman. Scott was given patent rights to the repair technique and materials used. Scott used his patents to secure the repair process, called it the ‘Metalock Repair Process’, and began to offer franchises under the Metalock Corporation trade name after starting his own operation in Long Island City, NY. Shortly thereafter, Thomas O. Oliver Ltd. (based in Ontario, Canada) was the first company to purchase a franchise.\nFred Lewis (a partner in the development process) purchased a franchise and began operation in Chicago, IL in 1942. The same year, George Jackman Sr. left T.O. Oliver Ltd. and formed Metal Locking Service, Inc. as a stand-alone company.\nHal Harman took forward his method - called Chainlock. Initially Harman and Scott both offered competing metal stitching repairs. Then, for several years, Harman and Scott proceeded to take each other to court, to contest patent infringements and design rights. Ultimately Harman succeeded and Scott had to concede the process ownership to others.\nThe first repairs, in the 1930s, were in hazardous oilfields. Just prior to and during WWII, the process was used secretly on US Naval vessels, the process becoming a standard repair method approved by the US Navy after the war. It was in this time period that the process was verified as a credible alternative to welding.\nOver the years alternative variations of the metal stitching processes were developed, they use terms like Metal Stitch, and Metal Locking, and Metalock to describe their repair process. Lock-N-Stitch is a slightly different stitching method, that was developed from the original stitching concept, by Gary J Reed.\nDevelopment of the process.\nMajor Edward Peckham, a Canadian engineer originally of the Canadian army, was so impressed by what he saw in Texas that he brought the metalock process to Europe, and in 1947 opened an office in London, England. Peckham registered the Metalock Casting Repair Service, which became Metalock (Britain) Ltd. In 1953, to coordinate the expansion of the new process, the Metalock International Association was started in London. An engineering standard was developed to ensure the best possible outcome for a metalock repair.\nDuring the early years, from the 1953 to the 1970s, research was applied to improve the process in Sweden, Germany and the UK. This resulted in improvement in two main areas; the creation of a material for the key that was designed for maximum strength under operating conditions. And the development of the key design and dimensions, and how to locate the keys in as best layout possible.\nDuring the mid 20th century, the process gained rapid popularity among engineers and in manufacturing. The evidence of this is in the publications of specialist engineering publications\nProcess description.\nThe metalock process consists of a series of steps, that uses metal alloy ‘locks’ or 'keys' that are inserted into the cast iron across and at right angles to the fracture. The process is applied to a fracture, or to a complete break in the material. There is often related damage caused in the break, that has to be cut out prior to repair.\nThe steps in the process are:\nOnce complete, the appearance this repair gives is one of a 'stitch' from the sewing of cloth, hence the common term 'metal stitching.’ This method has also been called ‘metal locking’ as it locks in the broken parts of the machine. The durability of the repair is normally high as the technician ensures that the repair maximises the original equipment strength design pattern.\nApplications.\nAs a cold repair process, metal stitching is applicable where heat should not be used, and in situations where the material cannot be successfully repaired by welding.\nSituations where application of heat would be problematic are particularly appropriate for cold metal stitching, examples include: oil installations and engine rooms. Often large equipment cannot be easily dismantled and removed for repairs, the metalock repair process can often be performed in-situ with little or no dismantling. It is this feature that created the foundation for the development of the process. More unusual onsite locations expanded to include the repair of ship propellers whilst they are fixed to the ship, large mining equipment that is located underground, and underwater repairs.\nWelding introduces thermal stresses into the base metal, and also changes the grain structure of the metal crystals - altering the characteristics and the strength of that part of the equipment. Heat also distorts the alignment of the original surface. Once the equipment is machined and returned to use, the parent metal is always significantly weaker. Often, the site of the original repair then subsequently fails.\nThe metal stitching repair process however tends to maintain alignment of original surfaces, since the lack of heat during the repair produces no distortion of the completed repair. In addition, the parent metal is not weakened due to material changes. Metal stitching dampens and absorbs compression stresses; providing a good ‘expansion joint’ for castings subject to thermal stresses. It distributes the tensional load away from fatigue points and maintains relieved conditions of inherent internal stresses where the rupture initially occurred. Where the repair involved a pressurized interface, the repair process has the ability to seal the join.", "Engineering,_Manufacturing": 0.9995536208, "qwen": "Yes"}
{"id": "49997022", "revid": "46333188", "url": "https://en.wikipedia.org/wiki?curid=49997022", "title": "Cyber manufacturing", "text": "Cyber manufacturing is a concept derived from cyber-physical systems (CPS) that refers to a modern manufacturing system that offers an information-transparent environment to facilitate asset management, provide reconfigurability, and maintain productivity. Compared with conventional experience-based management systems, cyber manufacturing provides an evidence-based environment to keep equipment users aware of networked asset status, and transfer raw data into possible risks and actionable information. Driving technologies include design of cyber-physical systems, combination of engineering domain knowledge and computer sciences, as well as information technologies. Among them, mobile applications for manufacturing is an area of specific interest to industries and academia.\nMotivation.\nThe idea of cyber manufacturing originates from the fact that Internet-enabled services have added business value in economic sectors such as retail, music, consumer products, transportation, and healthcare; however, compared to existing Internet-enabled sectors, manufacturing assets are less connected and less accessible in real-time. Besides, current manufacturing enterprises make decisions following a top-down approach: from overall equipment effectiveness to assignment of production requirements, without considering the condition of machines. This usually leads to inconsistency in operation management due to lack of linkage between factories, possible overstock in spare part inventory, as well as unexpected machine downtime. Such situation calls for connectivity between machines as a foundation, and analytics on top of that as a necessity to translate raw data into information that actually facilitates user decision making. Expected functionalities of cyber manufacturing systems include machine connectivity and data acquisition, machine health prognostics, fleet-based asset management, and manufacturing reconfigurability.\nTechnology.\nSeveral technologies are involved in developing cyber-manufacturing solutions. The following is a short description of these technologies and their involvement in cyber-manufacturing. \nDevelopment.\nIn 2013 the Office of Naval Research in the US Military has issued a proposal solicitation subjected for cyber-manufacturing.", "Engineering,_Manufacturing": 0.9922223687, "qwen": "Yes"}
{"id": "47737366", "revid": "1075749268", "url": "https://en.wikipedia.org/wiki?curid=47737366", "title": "Ti-6Al-2Sn-4Zr-2Mo", "text": "Ti-6Al-2Sn-4Zr-2Mo (UNS designation R54620), also known as Ti 6-2-4-2, is a near alpha titanium alloy known for its high strength and excellent corrosion resistance. It is often used in the aerospace industry for creating high-temperature jet engines and the automotive industry to create high performance automotive valves.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "47752705", "revid": "910180", "url": "https://en.wikipedia.org/wiki?curid=47752705", "title": "Automation technician", "text": "Automation technicians repair and maintain the computer-controlled systems and robotic devices used within industrial and commercial facilities to reduce human intervention and maximize efficiency. Their duties require knowledge of electronics, mechanics and computers. Automation technicians perform routine diagnostic checks on automated systems, monitor automated systems, isolate problems and perform repairs. If a problem occurs, the technician needs to be able to troubleshoot the issue and determine if the problem is mechanical, electrical or from the computer systems controlling the process. Once the issue has been diagnosed, the technician must repair or replace any necessary components, such as a sensor or electrical wiring. In addition to troubleshooting, Automation technicians design and service control systems ranging from electromechanical devices and systems to high-speed robotics and programmable logic controllers (PLCs). These types of systems include robotic assembly devices, conveyors, batch mixers, electrical distribution systems, and building automation systems. These machines and systems are often found within industrial and manufacturing plants, such as food processing facilities. Alternate job titles include field technician, bench technician, robotics technician, PLC technician, production support technician and maintenance technician.\nEducation and training.\nAutomation technician programs integrate computer programming with mechanics, electronics and process controls, They also commonly include coursework in hydraulics, pneumatics, programmable logic controllers, electrical circuits, electrical machinery and human-machine interfaces. Typical courses include math, communications, circuits, digital devices and electrical controls. Other courses include robotics, automation, electrical motor controls, programmable logic controllers, and computer-aided design. Good math and analytic skills are essential to understand automated systems and isolate problems. In addition to programming, Automation Technicians are expected to become proficient with various instruments and hand tools for troubleshooting, such as electrical multimeters, signal analyzers, and frequency counters.\nEmployers generally prefer applicants who have completed an automation technician certificate or associate degree. These programs can be completed at colleges and universities in either an in-class or online format. Some colleges, such as George Brown College, offer an online automation technician program that uses simulation software, LogixSim, to complete automation lab projects and assignments.\nOther relevant credentials to become an automation technician include mechatronics, robotics, and PLCs. Up-to-date credentials and certifications can enhance employment opportunities and keep technicians current with the latest technological developments. In addition to colleges and universities, other organizations and companies also offer credential programs in automation, including equipment manufacturers such as Rockwell and professional associations, such as the Electronics Technicians Association, Robotics Industries Association and the Manufacturing Skill Standards Council.\nCareer prospects.\nCareer opportunities for automation technicians include a wide range of manufacturing and service industries such as automotive, pharmaceutical, power distribution, food processing, mining, and transportation. Other career prospects include areas as machine assembly, troubleshooting and testing, systems integration, application support, maintenance, component testing and assembly, automation programming, robot maintenance and programming, technical sales and services.\nTypical job-related activities may involve:\nExperienced automation technicians with advanced training may become specialists or troubleshooters who help other technicians diagnose difficult problems, or work with engineers in designing equipment and developing maintenance procedures. Automation technicians with leadership ability also may eventually become maintenance supervisors or service managers. Due to the highly specialized skills and knowledge required, there are many opportunities available to automation technicians in the service sector where there is a great demand for contract and sub-contract work with smaller manufacturing and distribution companies. Some experienced automation technicians open their own design, installation and maintenance companies. They can also become wholesalers or retailers of automation equipment, including inside and outside sales of automation equipment and systems. \nBecause of their familiarity with control systems and equipment, automation technicians are particularly well qualified to become manufacturers' sales representatives. Other related opportunities include customer service, quality-control, quality-assurance and consulting.", "Engineering,_Manufacturing": 1.0000072718, "qwen": "Yes"}
{"id": "35676139", "revid": "143538", "url": "https://en.wikipedia.org/wiki?curid=35676139", "title": "Design for availability", "text": "Design for Availability is the design process for a system targeting availability of the system for guarantying readiness as the major part of goal specification. This design is generally used toward availability based contracts. Design for availability means that design process should start by given parameters of requirement space and maps them to design parameter space. However, the conventional trial and error of parameters set followed by sensitivity analysis might end to the same result area in the design plane.\nDescription.\nThe design parameters generally include reliability, maintainability of the system. Reliability will be the result of manufacturing of the system where as maintainability is coming from operational, maintenance logistics, inventory management, Prognostic Health Management (PHM) and supply chain design of the services that system require. The general usage of this philosophy of system design is geared toward outcome-based contracts. Availability is the major factor of operational effectiveness along with performance of the system. Availability based contracts are not as complicated as performance based contract because the discussion over metrics and requirement is less obscure to define for customer and designer. Minimum required availability of complex system is a key factor of many distributed and repairable systems like ATM network or Airliner.\nIn Availability-based Contracts instead of parts, supplier is paid for a guaranteed level of services and performance a and system capability, like availability-based tariff for electric power. The supplier often has to guarantee the availability and preparedness of system at lesser costs by considering the logistics as part of design. The contractor will also have more control over logistics and supply chain of system. The key point of using availability instead of Performance is that combining availability of different part of one platform or system from its subsets is feasible and easy unlike dealing with obscure measures of performance in Performance based logistics.\nRecent interest in availability contracts that specify a required availability has created an interest in deriving system design and support parameters directly from an availability-based contracts. But, a point to point allocation from parameter of operation and support to meet availability requirement in the performance space, given the required availability distribution is a direct way of design which must be followed by a sensitivity analysis and robustness of parameters. However, determining design parameters from an availability requirement is a stochastic reverse design problem.\nEvaluating an availability requirement is a challenge for manufacturers and supporters of systems because determining how to deliver a specific availability is not trivial. The required availability can be defined over the instance of system or over the fleet. It can be defined over different time windows or in different geographical boxes. However availability optimization approaches provide solutions only at selected points in time (not all times), using mean time to failure (or fixed rate demand) and mean time to repair as deterministic values as part of convex optimization.\nAvailability engineering in network world is generally toward reducing unplanned downtime or planned downtime by providing redundancy or fast switching systems. This area of design is the subject of different discipline with different approach. The main difference between network industry and manufacturing availability is that former is more targeting toward decreasing downtime where as in reliability world it might be seen as using higher reliability part in a cost-effective manner.", "Engineering,_Manufacturing": 0.9997643828, "qwen": "Yes"}
{"id": "1872794", "revid": "12580852", "url": "https://en.wikipedia.org/wiki?curid=1872794", "title": "Thin small outline package", "text": "Thin small outline package (TSOP) is a type of surface mount IC package. They are very low-profile (about 1mm) and have tight lead spacing (as low as 0.5mm).\nThey are frequently used for RAM or Flash memory ICs due to their high pin count and small volume. In some applications, they are being supplanted by ball grid array packages which can achieve even higher densities. The prime application for this technology is memory. SRAM, flash memory, FSRAM and E2PROM manufacturers find this package well suited to their end-use products. It answers the needs required by telecom, cellular, memory modules, PC cards (PCMCIA cards), wireless, netbooks and countless other product applications.\nTSOP is the smallest leaded form factor for flash memory.\nHistory.\nThe TSOP package was developed to fit the reduced package height available in a PCMCIA PC Card.\nPhysical properties.\nTSOPs are rectangular in shape and come in two varieties: Type I and Type II. Type I ICs have the pins on the shorter side and Type II have the pins on the longer side. The table below shows basic measurements for common TSOP packages.\nHTSOP.\nHTSOP (Heatsink TSOP) is a variant of TSOP with an exposed pad on the bottom side. The pad is soldered to the PCB to transfer heat from the package to the PCB.\nSimilar packages.\nThere are a variety of small form-factor IC carrier available other than TSOPs", "Engineering,_Manufacturing": 1.0000060797, "qwen": "Yes"}
{"id": "1873277", "revid": "1157568516", "url": "https://en.wikipedia.org/wiki?curid=1873277", "title": "Residual stress", "text": "In materials science and solid mechanics, residual stresses are stresses that remain in a solid material after the original cause of the stresses has been removed. Residual stress may be desirable or undesirable. For example, laser peening imparts deep beneficial compressive residual stresses into metal components such as turbine engine fan blades, and it is used in toughened glass to allow for large, thin, crack- and scratch-resistant glass displays on smartphones. However, unintended residual stress in a designed structure may cause it to fail prematurely.\nResidual stresses can result from a variety of mechanisms including inelastic (plastic) deformations, temperature gradients (during thermal cycle) or structural changes (phase transformation). Heat from welding may cause localized expansion, which is taken up during welding by either the molten metal or the placement of parts being welded. When the finished weldment cools, some areas cool and contract more than others, leaving residual stresses. Another example occurs during semiconductor fabrication and microsystem fabrication when thin film materials with different thermal and crystalline properties are deposited sequentially under different process conditions. The stress variation through a stack of thin film materials can be very complex and can vary between compressive and tensile stresses from layer to layer.\nApplications.\nWhile uncontrolled residual stresses are undesirable, some designs rely on them. In particular, brittle materials can be toughened by including compressive residual stress, as in the case for toughened glass and pre-stressed concrete. The predominant mechanism for failure in brittle materials is brittle fracture, which begins with initial crack formation. When an external tensile stress is applied to the material, the crack tips concentrate stress, increasing the local tensile stresses experienced at the crack tips to a greater extent than the average stress on the bulk material. This causes the initial crack to enlarge quickly (propagate) as the surrounding material is overwhelmed by the stress concentration, leading to fracture.\nA material having compressive residual stress helps to prevent brittle fracture because the initial crack is formed under compressive (negative tensile) stress. To cause brittle fracture by crack propagation of the initial crack, the external tensile stress must overcome the compressive residual stress before the crack tips experience sufficient tensile stress to propagate.\nThe manufacture of some swords utilises a gradient in martensite formation to produce particularly hard edges (notably the katana). The difference in residual stress between the harder cutting edge and the softer back of the sword gives such swords their characteristic curve.\nIn toughened glass, compressive stresses are induced on the surface of the glass, balanced by tensile stresses in the body of the glass. Due to the residual compressive stress on the surface, toughened glass is more resistant to cracks, but shatter into small shards when the outer surface is broken. A demonstration of the effect is shown by Prince Rupert's Drop, a material-science novelty in which a molten glass globule is quenched in water: Because the outer surface cools and solidifies first, when the volume cools and solidifies, it \"wants\" to take up a smaller volume than the outer \"skin\" has already defined; this puts much of the volume in tension, pulling the \"skin\" in, putting the \"skin\" in compression. As a result, the solid globule is extremely tough, able to be hit with a hammer, but if its long tail is broken, the balance of forces is upset, causing the entire piece to shatter violently.\nIn certain types of gun barrels made with two tubes forced together, the inner tube is compressed while the outer tube stretches, preventing cracks from opening in the rifling when the gun is fired.\nCompressive residual stress.\nCommon methods to induce compressive residual stress are shot peening for surfaces and High frequency impact treatment for weld toes. Depth of compressive residual stress varies depending on the method. Both methods can increase lifetime of constructions significantly. \nCreation of residual stress.\nThere are some techniques which are used to create uniform residual stress in a beam. For example, the four point bend allows inserting residual stress by applying a load on a beam using two cylinders.\nMeasurement techniques.\nOverview.\nThere are many techniques used to measure residual stresses, which are broadly categorised into destructive, semi-destructive and non-destructive techniques. The selection of the technique depends on the information required and the nature of the measurement specimen. Factors include the depth/penetration of the measurement (surface or through-thickness), the length scale to be measured over (macroscopic, mesoscopic or microscopic), the resolution of the information required, and also the composition geometry and location of the specimen. Additionally, some of the techniques need to be performed in specialised laboratory facilities, meaning that \"on-site\" measurements are not possible for all of the techniques.\nDestructive techniques.\nDestructive techniques result in large and irreparable structural change to the specimen, meaning that either the specimen cannot be returned to service or a mock-up or spare must be used. These techniques function using a \"strain release\" principle; cutting the measurement specimen to relax the residual stresses and then measuring the deformed shape. As these deformations are usually elastic, there is an exploitable linear relationship between the magnitude of the deformation and magnitude of the released residual stress. Destructive techniques include:\nSemi-destructive techniques.\nSimilarly to the destructive techniques, these also function using the \"strain release\" principle. However, they remove only a small amount of material, leaving the overall integrity of the structure intact. These include:\nNon-destructive techniques.\nThe non-destructive techniques measure the effects of relationships between the residual stresses and their action of crystallographic properties of the measured material. Some of these work by measuring the diffraction of high frequency electromagnetic radiation through the atomic lattice spacing (which has been deformed due to the stress) relative to a stress-free sample. The Ultrasonic and Magnetic techniques exploit the acoustic and ferromagnetic properties of materials to perform relative measurements of residual stress. Non-destructive techniques include:\nRelief of residual stress.\nWhen undesired residual stress is present from prior metalworking operations, the amount of residual stress may be reduced using several methods. These methods may be classified into thermal and mechanical (or nonthermal) methods. All the methods involve processing the part to be stress relieved as a whole.\nThermal method.\nThe thermal method involves changing the temperature of the entire part uniformly, either through heating or cooling. When parts are heated for stress relief, the process may also be known as stress relief bake. Cooling parts for stress relief is known as cryogenic stress relief and is relatively uncommon.\nStress relief bake.\nMost metals, when heated, experience a reduction in yield strength. If the material's yield strength is sufficiently lowered by heating, locations within the material that experienced residual stresses greater than the yield strength (in the heated state) would yield or deform. This leaves the material with residual stresses that are at most as high as the yield strength of the material in its heated state.\nStress relief bake should not be confused with annealing or tempering, which are heat treatments to increase ductility of a metal. Although those processes also involve heating the material to high temperatures and reduce residual stresses, they also involve a change in metallurgical properties, which may be undesired.\nFor certain materials such as low alloy steel, care must be taken during stress relief bake so as not to exceed the temperature at which the material achieves maximum hardness (See Tempering in alloy steels).\nCryogenic stress relief.\nCryogenic stress relief involves placing the material (usually steel) into a cryogenic environment such as liquid nitrogen. In this process, the material to be stress relieved will be cooled to a cryogenic temperature for a long period, then slowly brought back to room temperature.\nNonthermal methods.\nMechanical methods to relieve undesirable surface tensile stresses and replace them with beneficial compressive residual stresses include shot peening and laser peening. Each works the surface of the material with a media: shot peening typically uses a metal or glass material; laser peening uses high intensity beams of light to induce a shock wave that propagates deep into the material.", "Engineering,_Manufacturing": 0.9999966621, "qwen": "Yes"}
{"id": "27776362", "revid": "39374154", "url": "https://en.wikipedia.org/wiki?curid=27776362", "title": "Lawler's algorithm", "text": "Lawler's algorithm is a powerful technique for solving a variety of constrained scheduling problems. particularly single-machine scheduling. The algorithm handles any precedence constraints. It schedules a set of simultaneously arriving tasks on one processor with precedence constraints to minimize maximum tardiness or lateness. Precedence constraints occur when certain jobs must be completed before other jobs can be started.\nObjective functions.\nThe objective function is assumed to be in the form formula_1, where formula_2 is any nondecreasing function and formula_3 is the flow time. When formula_4, the objective function corresponds to minimizing the maximum lateness, where formula_5 is due time for job formula_6 and formula_7 lateness of job formula_6. Another expression is formula_9, which corresponds to minimizing the maximum tardiness.\nAlgorithm.\nThe algorithm builds the schedule back to front. For each scheduling step, it looks only at the tasks that no other tasks depend on, and puts the one with the latest due date at the end of the schedule queue. Then it repeats this process until all jobs are scheduled. \nThe algorithm works by planning the job with the least impact as late as possible. Starting at formula_10 that formula_11 is the production time of job formula_12.\n formula_13 set of already scheduled jobs (at start: S = formula_14)\n formula_15 set of jobs whose successors have been scheduled (at start: all jobs without successors)\n formula_16 time when the next job will be completed (at start: formula_10)\n whileformula_18 do\n select formula_19 such that formula_20\n schedule formula_12 such that it completes at time formula_16\n add formula_12 to formula_13, delete formula_12 from formula_15 and update formula_15.\n formula_28\n end while\nExample 1.\nAssuming there are three jobs: t1, t2, and t3, with the following precedence constraints:\nAnd the following deadlines (due date in a month)\nNow we construct the required set of jobs:\nRepeat the following steps until J is empty:\nDo the next round: \nDo the next round: \nJ is now empty. The end.\nExample 2.\nA more complex example, with simplified steps:\nThe jobs and precedence constraints are shown below: a parent node --> child node in the tree.\nThe due dates of jobs are shown underneath of each node of the tree in parentheses. \nNow look at the set of jobs without any successors, find the one with latest due date, put it into the front of S: ", "Engineering,_Manufacturing": 0.9994509816, "qwen": "Yes"}
{"id": "27782265", "revid": "959742", "url": "https://en.wikipedia.org/wiki?curid=27782265", "title": "2010–11 UEFA Europa League qualifying phase", "text": "This article details the 2010–11 UEFA Europa League qualifying phase and play-off round.\nEach tie was played over two legs, with each team playing one leg at home. The team that had the higher aggregate score over the two legs progressed to the next round. In the event that aggregate scores finished level, the away goals rule was applied; i.e., the team that scored more goals away from home over the two legs progressed. If away goals were also equal, then 30 minutes of extra time was played, divided into two 15-minute halves. The away goals rule was again applied after extra time; i.e., if there were goals scored during extra time and the aggregate score was still level, the visiting team qualified by virtue of more away goals scored. If no goals were scored during extra time, the tie was decided by a penalty shootout.\n\"All times are CEST (UTC+2)\"\nRound and draw dates.\nAll draws were held at UEFA headquarters in Nyon, Switzerland.\nMatches may also be played on Tuesdays or Wednesdays instead of the regular Thursdays due to scheduling conflicts.\nTeams.\nBelow are the 160 teams involved in the qualifying phase and play-off round, grouped by their starting rounds. The 37 winners of the play-off round qualified for the group stage to join the 10 losing teams from the Champions League play-off round, and the title holders, Atlético Madrid.\nIn each round, teams were seeded based on their 2010 UEFA club coefficients. Prior to the draw, UEFA may form \"groups\" in accordance with the principles set by the Club Competitions Committee, but they are purely for convenience of the draw and do not resemble any real groupings in the sense of the competition, while ensuring that teams from the same association not drawn against each other.\nCL-c Losing teams from the Champions League third qualifying round (Champions Path)\nCL-n Losing teams from the Champions League third qualifying round (Non-Champions Path)\nFirst qualifying round.\nMatches.\nSecond leg.\n\"Anorthosis won 4–0 on aggregate.\"\n\"Tauras Tauragė won 5–4 on aggregate.\"\n\"Qarabağ won 5–2 on aggregate.\"\n\"Mogren won 5–0 on aggregate.\"\n\"Šibenik won 3–0 on aggregate.\"\n\"Dinamo Tbilisi won 2–1 on aggregate.\"\n\"1–1 on aggregate. Olimpia won on away goals.\"\n\"Bnei Yehuda won 1–0 on aggregate.\"\n\"Portadown won 2–1 on aggregate.\"\n\"MYPA won 7–0 on aggregate.\"\n\"Dnepr Mogilev won 8–2 on aggregate.\"\n\"Randers won 7–3 on aggregate.\"\n\"1–1 on aggregate. Dacia won on away goals.\"\n\"Győri ETO won 5–3 on aggregate.\"\n\"KF Tirana won 1–0 on aggregate.\"\n\"Gefle won 4–1 on aggregate.\"\n\"Rabotnički won 11–0 on aggregate.\"\n\"TPS won 7–1 on aggregate.\"\n\"Zrinjski won 4–2 on aggregate.\"\n\"Dundalk won 5–4 on aggregate.\"\n\"Kalmar FF won 4–0 on aggregate.\"\n\"Široki Brijeg won 5–0 on aggregate.\"\n\"Zestafoni won 5–0 on aggregate.\"\n\"KR Reykjavík won 5–2 on aggregate.\"\n\"Ruch Chorzów won 3–1 on aggregate.\"\n\"Torpedo Zhodino won 6–1 on aggregate.\"\nSecond qualifying round.\nMatches.\nSecond leg.\n\"Rabotnički won 1–0 on aggregate.\"\n\"Teteks won 3–1 on aggregate.\"\n\"OFK Beograd won 3–2 on aggregate.\"\n\"Zestafoni won 3–1 on aggregate.\"\n\"Maccabi Tel Aviv won 3–2 on aggregate.\"\n\"Spartak Zlatibor Voda won 5–3 on aggregate.\"\n\"Qarabağ won 3–2 on aggregate.\"\n\"2–2 on aggregate. Cercle Brugge won on away goals.\"\n\"3–3 on aggregate. Dnepr Mogilev won on away goals.\"\n\"Austria Wien won 3–2 on aggregate.\"\n\"2–2 on aggregate. Molde won on away goals.\"\n\"Baník Ostrava won 6–0 on aggregate.\"\n\"Dinamo Minsk won 10–1 on aggregate.\"\n\"Karpaty Lviv won 6–2 on aggregate.\"\n\"Kalmar FF won 2–0 on aggregate.\"\nReplay:\n\"MYPA won 8–0 on aggregate.\"\n\"Dinamo Tbilisi won 4–2 on aggregate.\"\n\"Randers won 4–1 on aggregate.\"\n\"Elfsborg won 3–1 on aggregate.\"\n\"APOEL won 6–1 on aggregate.\"\n\"Utrecht won 5–1 on aggregate.\"\n\"Shamrock Rovers won 2–1 on aggregate.\"\n\"Dinamo București won 7–1 on aggregate.\"\n\"Anorthosis won 3–2 on aggregate.\"\n\"Wisła won 7–0 on aggregate.\"\n\"Brøndby won 3–0 on aggregate.\"\n\"Levski Sofia won 8–0 on aggregate.\"\n\"Beşiktaş won 7–0 on aggregate.\"\n\"1–1 on aggregate. Ruch won on away goals.\"\n\"Rapid Wien won 6–2 on aggregate.\"\n\"Maribor won 3–1 on aggregate.\"\n\"Bangor City won 3–2 on aggregate.\"\n\"Győri ETO won 5–0 on aggregate.\"\n\"Zrinjski won 13–3 on aggregate.\"\n\"Olympiacos won 11–1 on aggregate.\"\n\"Lausanne-Sport won 2–1 on aggregate.\"\n\"Marítimo won 6–4 on aggregate.\"\n\"Cliftonville won 1–0 on aggregate.\"\n\"Budućnost Podgorica won 4–2 on aggregate.\"\n\"Motherwell won 2–0 on aggregate.\"\nThird qualifying round.\nMatches.\nSecond leg.\n\"Rapid Wien won 4–1 on aggregate.\"\n\"Elfsborg won 7–1 on aggregate.\"\n\"Galatasaray won 7–3 on aggregate.\"\n\"Dnepr Mogilev won 3–1 on aggregate.\"\n\"Karpaty Lviv won 2–0 on aggregate.\"\n\"Qarabağ won 4–2 on aggregate.\"\n\"Dinamo Minsk won 3–2 on aggregate.\"\n\"Sturm Graz won 3–1 on aggregate.\"\n\"Anorthosis won 3–2 on aggregate.\"\n\"2–2 on aggregate. Sibir Novosibirsk won on away goals.\"\n\"AZ won 2–1 on aggregate.\"\n\"Dnipro Dnipropetrovsk won 3–2 on aggregate.\"\n\"Timișoara won 5–4 on aggregate.\"\n\"Brøndby won 3–1 on aggregate.\"\n\"Lausanne-Sport won 4–3 on aggregate.\"\n\"Utrecht won 4–1 on aggregate.\"\n\"Levski Sofia won 6–3 on aggregate.\"\n\"Aris won 4–3 on aggregate.\"\n\"Genk won 8–3 on aggregate.\"\n\"Beşiktaş won 4–1 on aggregate.\"\n\"2–2 on aggregate. Maccabi Tel Aviv won on away goals.\"\n\"APOEL won 4–1 on aggregate.\"\n\"Marítimo won 10–3 on aggregate.\"\n\"Slovan Bratislava won 3–2 on aggregate.\"\n\"Austria Wien won 6–1 on aggregate.\"\n\"Stuttgart won 5–4 on aggregate.\"\n\"Hajduk Split won 4–3 on aggregate.\"\n\"Liverpool won 4–0 on aggregate.\"\n\"CSKA Sofia won 5–1 on aggregate.\"\n\"Juventus won 3–0 on aggregate.\"\n\"Maribor won 6–2 on aggregate.\"\n\"1–1 on aggregate. Győri ETO won 4–3 on penalties.\"\n\"Motherwell won 4–1 on aggregate.\"\n\"Odense won 5–3 on aggregate.\"\n\"Sporting won 3–1 on aggregate.\"", "Engineering,_Manufacturing": 0.9998272061, "qwen": "Yes"}
{"id": "27795355", "revid": "222758", "url": "https://en.wikipedia.org/wiki?curid=27795355", "title": "Ion milling machine", "text": "Ion milling machine thins samples until they are transparent to electrons by firing ions (typically argon) at the surface from an angle and sputtering material from the surface. By making a sample electron transparent, it can be imaged and characterized in a transmission electron microscope (TEM). Ion beam milling may also be used for cross-section polishing prior to SEM analysis of materials that are difficult to prepare using mechanical polishing.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "15820908", "revid": "17843555", "url": "https://en.wikipedia.org/wiki?curid=15820908", "title": "Advances in Production Engineering & Management", "text": "Advances in Production Engineering & Management (APEM) is an interdisciplinary refereed journal. It is published quarterly by Production Engineering Institute (PEI), an organisational unit of the Faculty of mechanical engineering at the University of Maribor. The main goal of journal is to present high quality research developments in all areas of production engineering and production management, as well as their applications in industry and services, to a broad audience of academics and practitioners. Like most scientific journals, it can be obtained in print or in electronic form.\nAdvances in Production Engineering & Management is abstracted and indexed in the world’s leading bibliographic databases, including Web of Science (Science Citation Index Expanded – SCIE, Journal Citation Reports – JCR, and Current Contents – CC), Scopus, Inspec, EBSCO, and ProQuest.\nIn the Web of Science (THOMSON REUTERS) bibliographic database the journal is included into two categories:\n1. Engineering, Manufacturing; \n2. Material Science, Multidisciplinary.\nThe journal Advances in Production Engineering & Management has received its first impact factor calculated by Thomson Reuters in June 2016. The current impact factor is 1.125 (Journal Citation Reports 2016, year 2015). ", "Engineering,_Manufacturing": 0.9999847412, "qwen": "Yes"}
{"id": "40953825", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=40953825", "title": "Volvo Concept Coupe", "text": "The Volvo Concept Coupe is a concept car that was first revealed at the 2013 Frankfurt Motor Show. The concept car was based on Volvo's new platform Scalable Product Architecture (SPA), designed to provide the technical foundation for future Volvo models.\nThe front wheels are driven by a four-cylinder, two-litre petrol engine from Volvo's Volvo Engine Architecture (VEA) engine family, fed by both turbocharger and supercharger. The rear wheels are driven by an electric motor, making this car a plug in hybrid.\nThe engines have a combined peak power of and maximum torque of . The car was designed by Volvo's head of design Thomas Ingenlath, taking inspiration from the Volvo P1800 of the 1960s. Volvo Cars' subsidiary, Polestar, put the car into production, and re-badged it as the Polestar 1.", "Engineering,_Manufacturing": 1.0000065565, "qwen": "Yes"}
{"id": "21319490", "revid": "1110794645", "url": "https://en.wikipedia.org/wiki?curid=21319490", "title": "Product flow diagram", "text": "The product flow diagram (PFD) is a representation of the order by which a sequence of products is created according to product-based planning principles. It is related to the product breakdown structure (PBS).\nThe product flow diagram is a prescribed activity of the PRINCE2 project management methodology which mandates the use of product-based planning.\nFeatures.\nSome important features of the product flow diagram (PFD) include:\nThe product flow diagram is typically created iteratively with product descriptions and the product breakdown structure because as a project manager works through the logic they will identify missing products and additional information about products.", "Engineering,_Manufacturing": 0.999738276, "qwen": "Yes"}
{"id": "37134444", "revid": "45792121", "url": "https://en.wikipedia.org/wiki?curid=37134444", "title": "List of bottling companies", "text": "This is a list of bottling companies. A bottling company is a commercial enterprise whose output is the bottling of beverages for distribution. A bottler is a company which mixes drink ingredients and fills up cans and bottles with the drink. The bottler then distributes the final product to wholesale sellers in a geographic area. Large companies like The Coca-Cola Company and Dannizota sell their product to bottlers such as the Coca-Cola Bottling Co., who then bottle and distribute it.\nM.\n", "Engineering,_Manufacturing": 1.0000067949, "qwen": "Yes"}
{"id": "45436992", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=45436992", "title": "CMF design", "text": "Color, Materials, Finish (CMF) is an area of industrial design that focuses on the chromatic, tactile and decorative identity of products and environments.\nCharacteristics.\nCMF design uses metadesign logic, the simultaneous planning of the identity of entire ranges of products for a given brand. This makes it possible, for example, to adopt a single color matrix, instead of using a series of separate and different color cards for each line of products, as previously done. A contribution to the development of this approach to design was the impetus provided by the proliferation in the 1980s of complete ranges of new systemic products.\nBrand products are often thought up by different designers who through the use of ad-hoc CMF design manuals can work together to ensure a unique but coordinated identity for the products. This working process is advantageous in terms of the choice of color base for systemic products that are either of heterogeneous origin or are considered OEM products. The latter, even if characterized by different forms, can be connoted with the base colors or materials that are representative of the brand due to CMF design. Since CMF design manuals and the color matrix have a prescriptive role, the designers who create them are rarely involved in the applicative distribution either of colors, materials or finishes of individual products.", "Engineering,_Manufacturing": 0.999096036, "qwen": "Yes"}
{"id": "32609653", "revid": "41865877", "url": "https://en.wikipedia.org/wiki?curid=32609653", "title": "Kanto Auto Works", "text": " was a Japanese car manufacturer. It was a member of the Toyota Group. In July 2012, Kanto Auto Works and two other Toyota subsidiaries were merged to form Toyota Motor East Japan.\nHistory.\nIn April 1946, Kanto Auto Works was established in Yokosuka, Kanagawa Prefecture, Japan, as an independent company called \"Kanto Electric Motor Works\" which focused on repairing cars, assembling electric vehicles and producing bus bodies. In early 1948, it became a Toyota contractor, producing auto bodies. During its early years, the company also assembled some cars for Toyota (Toyota SB, Toyota Master, Toyota Crown). The company also diversified into other products such as yachts and prefabricated homes. In 1950, it adopted the \"Kanto Auto Works\" name. In 1960, the company became a permanent car assembler through a new Yokosuka plant. Later, the company replaced Yokosuka for car assembly with the Higashi-Fuji (established in 1968) and Iwate (established in 1993) plants.\nKanto Auto Works was a public company until the 2011 Tohoku earthquake, Toyota announced it would make it a wholly owned subsidiary. On July 1, 2012, Kanto Auto Works and two other Toyota subsidiaries (Central Motors and Toyota Motors Tohoku) were combined into a single company called Toyota Motor East Japan, Inc.", "Engineering,_Manufacturing": 1.0000070333, "qwen": "Yes"}
{"id": "20064886", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=20064886", "title": "Thick-film technology", "text": "Thick-film technology is used to produce electronic devices/modules such as surface mount devices modules, hybrid integrated circuits, heating elements, integrated passive devices and sensors. Main manufacturing technique is screen printing (stenciling), which in addition to use in manufacturing electronic devices can also be used for various graphic reproduction targets. It became one of the key manufacturing/miniaturisation techniques of electronic devices/modules during 1950s. Typical film thickness – manufactured with thick film manufacturing processes for electronic devices – is 0.0001 to 0.1 mm.\nThick-film circuits/modules are widely used in the automotive industry, both in sensors, e.g. mixture of fuel/air, pressure sensors, engine and gearbox controls, sensor for releasing airbags, ignitors to airbags; common is that high reliability is required, often extended temperature range also along massive thermocycling of circuits without failure. Other application areas are space electronics, consumer electronics, and various measurement systems where low cost and/or high reliability is needed.\nThe simplest form to utilise a thick film technology is a module substrate/board, where wiring is manufactured using thick film process. Additionally resistors and large tolerance capacitors can be manufactured with thick film methods. Thick film wiring can be made compatible with surface-mount technology (SMT), and if needed (due to tolerances and/or size requirements) surface-mountable parts (resistors, capacitors, ICs, etc.) can be assembled on a thick film substrate.\nThe manufacturing of thick film devices/modules is an additive process involving deposition of several (typically max 6–8) successive layers of conductive, resistive and dielectric layers onto an electrically insulating substrate using a screen-printing process.\nAs a low cost manufacturing method it is applicable to produce large volumes of discrete passive devices like resistors, thermistors, varistors and integrated passive devices.\nThick film technology is also one of the alternatives to be used in hybrid integrated circuits and competes and complements typically in electronics miniaturization (parts or elements/area or volume) with SMT based on PCB (printed circuit board)/PWB (printed wiring board) and thin film technology.\nSteps.\nA typical thick-film process would consist of the following stages:\nLasering of substrates.\nTypically thick film circuit substrates are Al2O3/alumina, beryllium oxide (BeO), aluminum nitride (AlN), stainless steel, sometimes even some polymers and in rare cases even silicon (Si) coated with silicon dioxide (SiO2)., Commonly used substrates for thick-film processes are 94 or 96% alumina. Alumina is very hard and lasering of the material is the most efficient way to machine it. The thick-film process is also a means of miniaturization, where one substrate normally contains many units (final circuits). With lasering it is possible to scribe, profile and drill holes. Scribing is a process where a line of laser pulses is fired into the material and 30–50% of the material is removed; this weakens the substrate, and after all other processes are completed the substrate can easily be divided into single units.\nProfiling is, for example, used a lot in sensor fabrication, where a circuit needs to fit round tubes or other different complex shapes.\nDrilling of holes can provide a \"via\" (conductive link) between the two sides of the substrate, normally hole sizes are in the range 0.15–0.2 mm.\nLasering before processing the substrates has a cost advantage to lasering or dicing using a diamond saw after processing.\nInk preparation.\nInks for electrodes, terminals, resistors, dielectric layers etc. are commonly prepared by mixing the metal or ceramic powders required with a solvent (ceramic thick film pastes) or polymer pastes to produce a paste for screen-printing. To achieve a homogeneous ink the mixed components of the ink may be passed through a three-roll mill. Alternatively, ready-made inks may be obtained from several companies offering products for the thick-film technologist.\nScreen-printing and its improvements.\nScreen-printing is the process of transferring an ink through a patterned woven mesh screen or stencil using a squeegee.\nFor improving accuracy, increasing integration density and improving line and space accuracy of traditional screen-printing photoimageable thick-film technology has been developed. Use of these materials however changes typically the process flow and needs different manufacturing tools.\nDrying/Curing.\nAfter allowing time after printing for settling of the ink, each layer of ink that is deposited is usually dried at a moderately high temperature of to evaporate the liquid component of the ink and fix the layer temporarily in position on the substrate so that it can be handled or stored before final processing. For inks based on polymers and some solder pastes that cure at these temperatures, this may be the final step that is required. Some inks also require curing by exposure to UV light.\nFiring.\nFor many of the metal, ceramic and glass inks used in thick film processes a high temperature (usually greater than 300 °C) firing is required to fix the layers in position permanently on the substrate.\nAbrasive Trimming of resistors.\nAfter firing the resistors can be trimmed using a precision abrasive cutting method first developed by S.S. White. The method involves a fine abrasive media, usually 0.027 mm aluminum oxide. The abrasive cutting is fed through a carbide nozzle tip that can be of different sizes. The nozzle is advanced through the fired resistor while the resistor element is monitored with probe contacts and when final value is reached the abrasive blast is shut off and the nozzle retracts to the zero start position. The abrasive technique can achieve very high tolerances with no heat and no cracking of the glass frit used in the ink formulation.\nLaser trimming of resistors.\nAfter firing, the substrate resistors are trimmed to the correct value. This process is named laser trimming. Many chip resistors are made using thick-film technology. Large substrates are printed with resistors fired, divided into small chips and these are then terminated, so they can be soldered on the PCB board. With laser trimming two modes are used; either passive trimming, where each resistor is trimmed to a specific value and tolerance, or active trimming, where the feedback is used to adjust to a specific voltage, frequency or response by laser trimming the resistors on the circuit while powered up.\nMounting of capacitors and semiconductors.\nThe development of the SMT process actually evolves from the thick film process. Also mounting of naked dies (the actual silicon chip without encapsulation) and wire bonding is a standard process, this provides the basis for miniaturization of the circuits as all the extra encapsulation is not necessary.\nSeparation of elements.\nThis step is often necessary because many components are produced on one substrate at the same time. Thus, some means of separating the components from each other is required. This step may be achieved by wafer dicing.\nIntegration of devices.\nAt this stage, the devices may require integrating with other electronic components, usually in the form of a printed circuit board. This may be achieved by wire bonding or soldering.\nProcess control of thick film manufacturing.\nThere are numerous steps in the thick film manufacturing, which need careful control like roughness of the substrate, curing temperatures and times of pastes, selected stencil thickness vs. paste type etc., Therefore number of used pastes and process steps define the complexity of the process and cost of the final product.\nDesigning circuits based on thick-film technology.\nSame or similar electronic design automation tools which are used for designing printed circuit boards can be used for designing thick film circuits. However, the compatibility of tooling formats with stencil manufacturing/manufacturer needs attention as well as the availability of the geometrical, electrical and thermal design rules for simulation and layout design from the final manufacturer.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "20080409", "revid": "46102395", "url": "https://en.wikipedia.org/wiki?curid=20080409", "title": "EE Technologies", "text": "Electronic Evolution Technologies, Inc. (also referred to as EE Technologies, Inc or EET) is a multi-national electronic manufacturing services (EMS) company headquartered in Reno, Nevada. EET provides full electronic and mechanical box build assembly services and also specializes in circuit board assembly for a variety of markets, including the automotive, medical, military and digital audio/video markets. The company operates a global manufacturing network with operations in the Americas and Mexico, providing services to original equipment manufacturers (OEMs). EET has been recognized as one of the top 20 contract manufacturers in the western United States.\nHistory.\nEE Technologies, Inc. was incorporated as Meridian Electronics in 1994. By 1999 Meridian Electronics had grown to $28 million a year in revenue. EE Technologies was spun off from Meridian Electronics in March 2000. In October 2000, the company moved into a new facility in South Reno, Nevada. In December 2002, the company expanded their facilities by allowing for improved production efficiencies and capabilities, as well as improved inventory management. Currently, the company employs over 180 people with facilities in the US and Mexico. EE Technologies, Inc recently settled a lawsuit with the Environmental Protection Agency for $80,000 over them failing to file required reports on toxic chemicals.\nOperations.\nEE Technologies, Inc's manufacturing network comprises locations in the Americas and Mexico. The company's services include design, engineering, manufacturing and systems assembly, fulfilment and after-market services.\nMexico Facility.\nIn October 2005, EE Technologies, Inc expanded further with the opening of a facility in Empalme, Sonora, Mexico. The equipment, process, and training in the Mexico facility mirror the operations in Reno, Nevada. Both facilities are ISO/TS 16949:2002 certified.", "Engineering,_Manufacturing": 0.9999938011, "qwen": "Yes"}
{"id": "20080539", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=20080539", "title": "Supply chain risk management", "text": "Supply chain risk management (SCRM) is \"the implementation of strategies to manage both everyday and exceptional risks along the supply chain based on continuous risk assessment with the objective of reducing vulnerability and ensuring continuity\".\nSCRM applies risk management process tools after consultation with risk management services, either in collaboration with supply chain partners or independently, to deal with risks and uncertainties caused by, or affecting, logistics-related activities, product availability (goods and services) or resources in the supply chain.\nSupply chain exposures.\nSCRM attempts to reduce supply chain vulnerability via a coordinated, holistic approach ideally involving all supply chain stakeholders, collectively identifying, analysing and addressing potential failure points or modes within or affecting the supply chain. Risks to the supply chain range from unpredictable natural events (such as tsunamis and pandemics) to counterfeit products, and reach across quality, security, to resiliency and product integrity. \nMitigation of supply chain risks can involve logistics, cybersecurity, finance and risk management disciplines, the ultimate goal being to maintain supply chain continuity in the event of scenarios or incidents which otherwise would have interrupted normal business and hence profitability. The cost-effectiveness of resilience and other measures is an important factor since, as long as things are running smoothly, they add to the costs of production. To reduce interruptions to supply chain management in terms of logistic there are logistics risk management programs which includes Defensive Driver Trainings, Fleet Audits, Cargo Loss Minimization, Road Safety, Warehouse Safety etc.\nSome supply chain logistics techniques such as supply-chain optimization and lean manufacturing can prejudice continuity and resilience. It is also becoming more common among businesses especially manufacturers to extend supplier quality management practices throughout supply chains. This approach is shown to increase transparency, reduce overhead costs, and improve operational efficiency.\nExtent of supply chain disruption.\nA survey in 2011 conducted by the Business Continuity Institute (BCI) and Zurich, with responses from over 559 companies across 65 countries, found that over 85% of companies had suffered at least one supply chain disruption during the year. Later BCI surveys have reported some reduction in this percentage (70% in 2016, down from 74% the previous year).\nThe 2011 survey respondents also noted that 40% of the reported disruptions originated upstream with sub-contractors rather than prime contractors or first-tier suppliers.\nThe 2016 survey also noted that one in three organizations had experienced cumulative losses of over €1 million per year because of supply chain disruptions, and 22% of businesses had experienced 11 or more disruptions.\nResilience.\nSupply chain risk management typically involves four processes: identification, assessment, treatment, risk reporting and communication, and monitoring of supply chain risks. However, due to the complexity of many supply chains, these processes might not be sufficient to ensure that all eventualities are prepared for. Therefore, the concept of supply chain risk management, which is cause-oriented, is often combined with the concept of supply chain resilience, which aims to ensure that the supply chain can cope with or bounce back from incidents irrespective of their cause or nature. Supply chain resilience is defined as \"the capacity of a supply chain to persist, adapt, or transform in the face of change\" Some theorists believe that technological updating to modernize management methods -to include digitalization, artificial intelligence, big data and robotics- along the entire path of supply chains will considerably contribute to their sustainability and resilience.\nTime to recover.\n\"Time to recover\" (TTR) is a valuable metric measured in weeks, originally introduced by Cisco and adopted by the Supply Chain Risk Leadership Council. TTR measures the time it takes a company to restore full operational output following a major supply chain disruption. The determination of TTR assumes that a facility is essentially unusable due to a major event, requiring extensive repairs and reconstruction, as well as re-sourcing and re-qualifying of key equipment used in manufacturing and other operations.\nMeasuring risk.\nSupply chain risk is a function of likelihood of an event's occurrence and its impact. Although this is the most popular methodology for quantifying risk, a drawback in the context of supply-chain risk is that it requires assessing likelihood or probability of many different event types across a number of supply-chain organisations and locations (potentially hundreds of thousands for, say, a major vehicle manufacturer). Thus, the range of possibilities is huge, frustrating and limiting the analysis possible in practice. The methodology may be appropriate for a smaller subset of locations and/or types or categories of risk. \nMost companies rely on 'risk scores' of various types such as financial risk score, operational risk score, resiliency score (R Score). These are readily available, relatively simple to understand and analyze, and hence can be effective, at least for first-pass identification of risks worthy of further analysis. Standards and certified compliance (such as ISO 9001) are also effective ways to raise the baseline to a known level.\nSupply chain resilience options.\nSome options to engineer an acceptable risk level in supply chains include:", "Engineering,_Manufacturing": 0.9929057956, "qwen": "Yes"}
{"id": "25573673", "revid": "39191556", "url": "https://en.wikipedia.org/wiki?curid=25573673", "title": "Riihimäki glass", "text": "Riihimäki glass  was a reputed glass company in Riihimäki, Finland, in operation from 1910, when it was founded by Mikko Adolf Kolehmainen, to 1990. Their production ranged from basic to high quality glass ornaments, which are now sought after as collectibles, especially some of their vases. Riihimäki products are readily available via collectors' web sites, as are their values.\nIt produced everyday glassware and art glass until 1976 and cut glass until 1977. After that, it made only machine produced glass and plastic packaging. Ahlstrom Corporation purchased the company in 1980, and closed the Riihimäki plant in 1990.\nAmong the designers associated with Riihimäki in its early decades were , Gunnel Nyman, and after 1945, (1959–1976), (1954–1955), Timo Sarpaneva, and (1968–1976), as well as Helena Tynell. It was Nanny Still who joined the design team by winning the Nordic art competition the firm held in 1949.\nFinnish Glass Museum.\nSince 1980, the Finnish Glass Museum has been housed in then a glass factory building where Riihimäki Glass started a manufacturing blown glass in 1921. The original owner of that facility was Paloheimo since 1914, which financially supported Riihimäki Glass at its latter stage of operation. The manufacturing at that factory shifted from glass to plastic packaging, then to screen printing.", "Engineering,_Manufacturing": 0.9999427795, "qwen": "Yes"}
{"id": "25579396", "revid": "25524306", "url": "https://en.wikipedia.org/wiki?curid=25579396", "title": "Army engineering maintenance", "text": "Army engineering maintenance consists of those engineers, technicians, and military organizations responsible for the expert repair and maintenance of army vehicles, weapon systems, and other equipment.\nArmy engineering maintenance should not be confused with military engineering which is distinctly separate and analogous to civil engineering while the former analogous to mechanical engineering and electrical engineering.\nOperational and tactical level focus.\nAt the operational and tactical levels, army engineering maintenance is focused on the repair and scheduled maintenance work required to keep army equipment fleets operational.\nStrategic level focus.\nAt the strategic level, army engineering maintenance is closely linked to military logistics. At this level, it includes work such as the design, development, and testing of new vehicles and weapon systems. It also includes lifecycle management activities once new systems become operational.", "Engineering,_Manufacturing": 0.9989506602, "qwen": "Yes"}
{"id": "25594029", "revid": "31421733", "url": "https://en.wikipedia.org/wiki?curid=25594029", "title": "DO-204", "text": "DO-204 is a family of diode semiconductor packages defined by JEDEC. This family comprises lead-mounted axial devices with round leads. Generally a diode will have a line painted near the cathode end.\nCommon variants.\nSeveral common packages are archived in DO-204 as variants, and may be referred to using their alternative names.\nDO-7.\nThe DO-7 (also known as DO-204-AA) is a common semiconductor package for 1N34A germanium diodes.\nDO-35.\nThe DO-35 (also known as DO-204-AH or SOD27) is a semiconductor package used to encapsulate signal diodes (i.e., diodes meant to handle small amounts of current and voltage). It is often used to package small signal, low power diodes such as 1N4148 (a 100 V, 300 mA silicon diode.)\nDO-41.\nThe DO-41 (also known as DO-204-AL or SOD66) is a common semiconductor package used to encapsulate rectifier diodes (i.e., diodes meant to handle larger currents and voltages than signal diodes). The name is derived from the JEDEC descriptor \"Diode Outline, Case Style 41\". DO-41 diodes are larger than signal diode packages such as DO-35, which are not required to handle large currents. The most common diode using this packaging is the 1N4001 to 1N4007 series of rectification diodes.", "Engineering,_Manufacturing": 0.9988979697, "qwen": "Yes"}
{"id": "27597500", "revid": "38020738", "url": "https://en.wikipedia.org/wiki?curid=27597500", "title": "Protean Electric", "text": "Protean Electric is an automotive technology company specializing in in-wheel motor technology. The company has developed an in-wheel, electric-drive system for hybrid, plug-in hybrid, and battery electric vehicles. Their technology creates a permanent magnet e-machine with relatively high torque and power density with the power electronics and controls packaged within the motor itself. Their in-wheel motor product is intended to be produced in low volume by Protean Electric and licensed in high volume to global automotive and Tier 1 automotive supply companies. Protean Electric is a privately held company with approximately 114 employees. Protean Electric has operations in the United States, United Kingdom, and China.\nTechnology.\nProtean Electric's in-wheel motor is intended to save space on board the vehicle by allowing the drive system to be mounted behind a conventional road wheel and apply torque directly to the wheel and tire.\nEach of Protean's in-wheel motors can deliver 80 kW (100 hp) and 1250 Nm (935 lb-ft) and weigh 36 kg (75 lbs.). They are sized to fit within the space of a conventional 16- or 18-inch road wheel. The electric motors are designed for use in front-, rear- and all-wheel drive vehicle applications and can be adapted to existing internal combustion engine powered cars and trucks to turn them into hybrids.\nSince Protean Electric’s motors fit behind the wheels of a vehicle, they can be used as part of a drive system that does not require a gearbox, differential, or drive shafts. This creates an energy-efficient drivetrain that potentially saves cost, reduces weight and frees up space on board the vehicle that was previously dedicated to drivetrain components. According to Protean Electric, its in-wheel motors can increase fuel economy by over 30 percent depending on the battery size and driving cycle in a hybrid or plug-in hybrid vehicle. It is also capable of enabling torque vectoring by applying individual torque at optimal levels to each wheel to improve vehicle safety and handling.\nProtean has been awarded over 120 patents for its technology and design, and more than 100 additional patent applications have been filed and are pending internationally and with specific countries in North America, Europe and Asia.\nIn-wheel motors offer the benefits of drastically improved vehicle packaging, simplified two-wheel or all-wheel-drive layouts, the option of through-the-road hybridization, more efficient regenerative braking, and the most direct wheel control possible. The downside is added unsprung weight which can impact handling performance. During their research efforts, Protean Electric and Lotus found that most negative effects of added unsprung mass could be eliminated by adding suspension damping, and that the ability to utilize accurate torque vectoring actually improved car's handling so much that the net effect of the whole arrangement was positive.\nAnother drawback of in-wheel motors is the fundamental physical reality that their location inside the wheel places them in much closer proximity to road impacts. In other words, an in-wheel motor must directly cope with these forces exerted on the wheel, without the cushioning effect of a suspension. This type of layout stands in contrast to the traditional mounting location of the motor in the vehicle body, an arrangement that ensures that a sudden road impact to the wheel is directly and immediately dealt with by the suspension, thereby ensuring that the vehicle body (containing the motor and all other components) is exposed to very little of the road shock. \nFurthermore, an in-wheel motor must also operate in much closer proximity to physical insults from the road, including road grit, water, and saltwater (from road-deicing salts in cold climate). These concerns must be addressed in the design and engineering of such motors.\nAdditionally, the location of in-wheel motors, combined with the fact that four of them are needed (for a four-wheel-drive vehicle), may result in more complicated maintenance. However, on the other hand, with in-wheel motors, no differentials are required, so this aspect serves to simplify the maintenance aspect.\nCompany Background.\nProtean has been developing in-wheel electric motors for several years. Protean Electric was founded in 2009 after PML Flightlink was put into administration in 2008. Protean Electric began to focus entirely on the in-wheel technology for automotive applications. \nProtean has been owned by BEDEO since October 2021, after buying the company from NEVS. \nThe suppliers and partners are: SKF, FEV, AB Mikroelektronik GmbH, Alcon, ATS Automation Tooling Systems, and Trelleborg Sealing Solutions.\nProtean Electric’s in-wheel motor technology was recognized by the World Economic Forum, which named Protean a 2012 Technology Pioneer and received recognition from Car and Driver magazine as one of the ten most promising technologies for 2013.", "Engineering,_Manufacturing": 0.9998475313, "qwen": "Yes"}
{"id": "28443302", "revid": "4626", "url": "https://en.wikipedia.org/wiki?curid=28443302", "title": "Knowledge-based configuration", "text": "Knowledge-based configuration, or also referred to as product configuration or product customization, is an activity of customising a product to meet the needs of a particular customer. The product in question may consist of mechanical parts, services, and software. Knowledge-based configuration is a major application area for artificial intelligence (AI), and it is based on modelling of the configurations in a manner that allows the utilisation of AI techniques for searching for a valid configuration to meet the needs of a particular customer.\nBackground.\nKnowledge-based configuration (of complex products and services) has a long history as an artificial intelligence application area, see, e.g. Informally, configuration can be defined as a \"special case of design activity, where the artifact being configured is assembled from instances of a fixed set of well-defined component types which can be composed conforming to a set of constraints\". Such constraints are representing technical restrictions, restrictions related to economic aspects, and conditions related to production processes. The result of a configuration process is a product configuration (concrete configuration), i.e., a list of instances and in some cases also connections between these instances. Examples of such configurations are computers to be delivered or financial service portfolio offers (e.g., a combination of loan and corresponding risk insurance).\nTheory and complexity of configuration.\nNumerous practical configuration problems can be analyzed by the theoretical framework of Najmann and Stein, an early axiomatic approach which does not presuppose any particular knowledge representation formalism. One important result of this methodology is that typical optimization problems (e.g. finding a cost-minimal configuration) are NP-complete. Thus they require (potentially) excessive computation time making heuristic configuration algorithms the preferred choice for complex artifacts (products, services).\nConfiguration systems.\nConfiguration systems or also referred to as configurators or mass customization toolkits, are one of the most successfully applied artificial intelligence technologies. Examples are the automotive industry, the telecommunication industry, the computer industry, and power electric transformers. Starting with rule-based approaches such as R1/XCON, model-based representations of knowledge (in contrast to rule-based representations) have been developed which strictly separate product domain knowledge from the problem solving one - examples thereof are the constraint satisfaction problem, the Boolean satisfiability problem, and different answer set programming (ASP) representations. There are two commonly cited conceptualizations of configuration knowledge. The most important concepts in these are components, ports, resources and functions. This separation of product domain knowledge and problem solving knowledge increased the effectiveness of configuration application development and maintenance, since changes in the product domain knowledge do not affect search strategies and vice versa.\nConfigurators are also often considered as \"open innovation toolkits\", i.e., tools which support customers in the product identification phase. In this context customers are innovators who articulate their requirements leading to new innovative products. \"Mass Confusion\" – the overwhelming of customers by a large number of possible solution alternatives (choices) – is a phenomenon which often comes with the application of configuration technologies. This phenomenon motivated the creation of personalized configuration environments taking into account a customer's knowledge and preferences.\nConfiguration process.\nCore configuration, i.e., guiding the user and checking the consistency of user requirements with the knowledge base, solution presentation and translation of configuration results into bill of materials (BOM) are major tasks to be supported by a configurator. Configuration knowledge bases are often built using proprietary languages.\nIn most cases knowledge bases are developed by knowledge engineers who elicit product, marketing and sales knowledge from domain experts. Configuration knowledge bases are composed of a formal description of the structure of the product and further constraints restricting the possible feature and component combinations.\nConfigurators known as characteristic based product configurators use sets of discrete variables that are either binary or have one of several values, and these variables define every possible product variation.\nSoftware and service configuration.\nRecently, knowledge based configuration has been extended to service and software configuration. Modeling software configuration has been based on two main approaches: feature modeling, and component-connectors. Kumbang domain ontology combines the previous approaches building on the tradition of knowledge based configuration.", "Engineering,_Manufacturing": 0.9998158813, "qwen": "Yes"}
{"id": "28446647", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=28446647", "title": "Metallurgical failure analysis", "text": "Metallurgical failure analysis is the process to determine the mechanism that has caused a metal component to fail. It can identify the cause of failure, providing insight into the root cause and potential solutions to prevent similar failures in the future, as well as culpability, which is important in legal cases. Resolving the source of metallurgical failures can be of financial interest to companies. The annual cost of corrosion (a common cause of metallurgical failures) in the United States was estimated by NACE International in 2012 to be $450 billion a year, a 67% increase compared to estimates for 2001. These failures can be analyzed to determine their root cause, which if corrected, would save reduce the cost of failures to companies.\nFailure can be broadly divided into functional failure and expected performance failure. Functional failure occurs when a component or process fails and its entire parent system stops functioning entirely. This category includes the common idea of a component fracturing rapidly. Expected performance failures are when a component causes the system to perform below a certain performance criterion, such as life expectancy, operating limits, or shape and color. Some performance criteria are documented by the supplier, such as maximum load allowed on a tractor, while others are implied or expected by the customer, such gas consumption (miles per gallon for automobiles).\nOften a combination of both environmental conditions and stress will cause failure. Metal components are designed to withstand the environment and stresses that they will be subjected to. The design of a metal component involves not only a specific elemental composition but also specific manufacturing process such as heat treatments, machining processes, etc. The huge arrays of different metals that result all have unique physical properties. Specific properties are designed into metal components to make them more robust to various environmental conditions. These differences in physical properties will exhibit unique failure modes. A metallurgical failure analysis takes into account as much of this information as possible during analysis. The ultimate goal of failure analysis is to provide a determination of the root cause and a solution to any underlying problems to prevent future failures.\nFailure investigation.\nThe first step in failure analysis is investigating the failure to collect information. The sequence of steps for information gathering in a failure investigation are:\nTechniques used.\nVarious techniques are used in the investigative process of metallurgical failure analysis.\nNon-destructive testing\":\" Non-destructive testing is a test method that allows certain physical properties of metal to be examined without taking the samples completely out of service. NDT is generally used to detect failures in components before the component fails catastrophically. \nDestructive testing\":\" Destructive testing involves removing a metal component from service and sectioning the component for analysis. Destructive testing gives the failure analyst the ability to conduct the analysis in a laboratory setting and perform tests on the material that will ultimately destroy the component.\nMetallurgical failure modes.\nThere is no standardized list of metallurgical failure modes and different metallurgists might use a different name for the same failure mode. The failure mode terms listed below are those accepted by ASTM, ASM, and/or NACE as distinct metallurgical failure mechanisms.\nPotential root causes.\nPotential root causes of metallurgical failures are vast, spanning the lifecycle of component from design to manufacturing to usage. The most common reasons for failures can be classified into the following categories:\nService or operation conditions.\nFailures due to service or operation conditions includes using a component outside of its intended conditions, such as an impact force or a high load. It can also include failures due to unexpected conditions in usage, such as an unexpected contact point that causes wear and abrasion or an unexpected humidity level or chemical presence that causes corrosion. These factors result in the component failing at an earlier time than expected.\nImproper maintenance.\nImproper maintenance would cause potential sources of fracture to go untreated and lead to premature failure of a component in the future. The reason for improper maintenance could be either intentional, such as skipping a yearly maintenance to avoid the cost, or unintentional, such as using the wrong engine oil.\nImproper testing or inspection.\nTesting and/or inspection are typically included in component manufacturing lines to verify the product meets some set of standards to ensure the desired performance in the field. Improper testing or inspection would circumvent these quality checks and could allow a part with a defect that would normally disqualify the component from field use to be sold to a customer, potentially leading to a failure.\nFabrication or manufacturing errors.\nManufacturing or fabrication errors occur during the processing of the material or component. For metal parts, casting defects are common, such as cold shut, hot tears or slag inclusions. It can also be surface treatment problems, processing parameters such as ramming a sand mold or wrong temperature during hardening.\nDesign errors.\nDesign errors arise when the desired use case was not properly accounted for, leading to a ineffective design, such as the stress state in service or potential corrosive agents in the service environment. Design errors often include dimensioning and materials selection, but it can also be the complete design.\nUse of computational methods for failure analysis.\nComputational methods have been increasing in popularity as a method to test possible root because they do not need to sacrifice a component to prove a root cause. Common cases where computational methods are used are for failures due to erosion, failures of components under complex stress states, and for predictive analyses. Computational fluid dynamics is used to determine the flow pattern and shear stresses on a component that had failed due to erosive wear. Finite element analysis is used to model components under complex stress states. Finite element analysis as well as phase field models can be used for predicting crack propagation and failure, which are then used to prevent failure by influencing component design.", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "10799089", "revid": "28398017", "url": "https://en.wikipedia.org/wiki?curid=10799089", "title": "Temper mill", "text": "A temper mill is a steel sheet or steel plate processing line composed of a horizontal pass cold rolling mill stand, entry and exit conveyor tables and upstream and downstream equipment depending on the design and nature of the processing system.\nThe primary purpose of a temper mill is to improve the surface finish on steel products.\nComponents.\nA typical type of temper mill installation includes entry equipment for staging and accepting hot rolled coils of steel which have been hot wound at the end of a hot strip mill or hot rolled plate mill. Also included in a typical temper mill installation are pinch rolls, a leveler (sometimes two levelers), a shear for cutting the finished product to pre-determined lengths, a stacker for accumulating cut lengths of product\nSometimes a temper mill installation includes a re-coil line where the finished product is a coil instead of bundles of cut lengths of product. Maximum product flexibility capability could be attained if the installation was arranged to produce both coils and bundles of cut to length product.\nThe heart of the temper mill is the cold rolling mill stand which produces the temper pass. It will include electric powered drive motors and speed reduction gearing suited to the process desired. The design of the rolling mill can be a 2-high or 4-high (even 6-high in some cases). The mill stand can be work roll driven or back up roll driven. The mill can be designed with hydraulic work roll bending or back up roll bending. Installations typically have a single rolling mill stand, but may have two. Pinch rolls provide back tension for the pay off reel in the entry section and entry and exit tension for the temper pass.\nFunction.\nThe process goal is physical property enhancement through cold forming of the steel product in the bite of the work rolls. The physical properties that are enhanced by the temper pass due to elongation of the product include:\nTypical elongation produced in the product is 0.5% to 2%. Product dimensions vary. Thicknesses include typical sheet metal gauges up to 1.00\" thick plate. Widths vary from 36\" to 125\".\nThe finish of the rolled product is controlled by using rolls having a variety of surface finishes designed to impart the desired finish to the product. Roll finishes range from ground and polished rolls to impart a bright finish, to shot-blasted or electric-discharged textured rolls that produce a dull, velvety finish on the steel surface.\nTypical auxiliary equipment includes PLC based controls, overhead traveling cranes, roll changing equipment, roll grinding equipment, hydraulic power unit(s), bundle lifting devices, Coil handling devices, etc.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "10811415", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=10811415", "title": "Pallet racking", "text": "Pallet rack is a material handling storage aid system designed to store materials on pallets (or “skids”). Although there are many varieties of pallet racking, all types allow for the storage of palletized materials in horizontal rows with multiple levels. Forklift trucks are usually required to place the loaded pallets onto the racks for storage. Since the Second World War, pallet racks have become a ubiquitous element of most modern warehouses, manufacturing facilities, retail centers, and other storage and distribution facilities. All types of pallet racking increase storage density of the stored goods. Costs associated with the racking increases with increasing storage density.\nSelective pallet racking systems.\nSelective pallet racking is a common pallet racking system in use today. Selective pallet racking systems typically come in one of two configurations: a roll formed, or clip-in configuration, and a structural bolt-together configuration.\nStructural pallet racking can be designed into the structure of the building itself, so that the upright columns are simultaneously used to support the roof of the storage facility, in which case the structural pallet rack uprights replace the storage building's vertical support I-beams. This system is a rack supported building.\nSelective pallet rack systems provide easy accessibility to all products at all times - important if the inventory is rapidly depleted and restocked (called quick turnover). A selective pallet rack system is commonly used in a \"big-box\" distribution application, as well as in retail store inventory rooms, cold storage applications, wholesale stores, etc.\nCommon components of selective rack include the following:\nVery narrow aisle (VNA) is the use of selective pallet racking in a tighter configuration to provide maximum space utilization within a storage facility. These systems typically operate in conjunction with wire-guided or rail-guided reach-truck systems. A wire-guided system consists of a wire embedded in the concrete floor that provides tracking for the reach-truck. A rail-guided system consists of angle iron bolted to the floor down the length of each row. Typically, the angle iron is 4” by 3” and ¼” - ⅜” inches thick. A distinct advantage of a narrow aisle pallet racking is fast picking without large aisles which results in improved use of space. When there is limited space, a compact storage method is ideal. Fully adjustable system flexibility and space saving aisles can be manipulated as one to give the greatest amount of pallet storage locations.\nOther common types.\nMany types of pallet storage racks are available with different designs to fulfill specific functions or create specific advantages. To create the ideal pallet racking system, several considerations should be taken into account:\nSome of the most common types of pallet rack systems used include:\nMobilized storage system has helped many organizations reduce or eliminate new building construction costs, auxiliary warehouses, building expansions, and decrease ongoing operational costs (lighting, energy, insurance) by redistributing the use of their storage floor space.\nSome disadvantages of high density pallet storage systems are; less access to all stock at any given moment (although if the stored product is all the same, it should not matter), and the expense of such systems. Selective pallet rack systems are considerably less expensive per pallet position than their higher density counterparts. In most medium to large facilities, however, high density pallet rack systems are essential, since they provide the efficiency of time and high cost facility space is better optimized.\nIdentifying the brand of racking systems is important to order compatible shelving or resell the racks. It is possible to differentiate between the many pallet rack brands by looking at the shape of the vertical beams, increments of height adjustment and the shape of the holes on the vertical beams.\nSafety considerations.\nBecause of the size and weight of pallets, safety is relevant.\nWorkers must pay attention to any loose components in the pallet rack system, and also take the time to report any damage in the pallet rack frame. Such frame damage could cause the pallets to fall.\nIt is the owner's legal responsibility to communicate this important warning to all who are around storage racks: \"Never climb on racks during or after assembly. Storage racks are not designed to be stepped on or climbed on. A slip or fall may result in serious injury.\" 'It is especially important to have highly visible warning signs if the pallet rack system is used in retail environments, such as wholesale centers, where the public is present.\nQuality pallets that are not damaged must be used. To save money, or perhaps from neglectful management, some warehouses use pallets until they become faulty and dangerous. Regular inspection of pallets for broken or fractured planks or stringers, protruding nails, and missing support blocks is essential. Damaged pallets can cause loading and unloading problems; for example, loose stringers can get hung up on the pallet racks, which can cause loads to fall from high positions. Also, faulty pallets can cause obstruction problems in flow systems by jamming certain pallet rack designs.\nProper motorized equipment must be used for the application. Obstructing the end of aisles by staging pallets in these areas can cause severe and potentially fatal injuries and accidents. Overloading or exceeding the recommended load specifications for a racking system may cause a catastrophic failure of your storage rack system. Rack audits (safety checks) must be performed regularly by a qualified inspector familiar with RMI design and safety standards. Food products must follow FDA regulations and use approved pallet racks.\nLoad containment systems for pallet racks.\nPallet racks are used throughout industry and distribution facilities for bulk storage of items. Generally, the items stored are boxed goods stacked on pallets which are placed on the rack. The pallets are accessed by some type of mechanized lifting and retrieval device. Sides of a pallet rack must be accessible by the mechanized device for storage and retrieval of goods. Thus these \"access sides” must be open; entry to them cannot be permanently blocked/guarded.\nHowever, there are instances where an aisle way is designated along a row of pallet rack for pedestrian or other traffic and not for operational access by the lifting or retrieval device. When a pedestrian or other traffic aisle way is designated along a run of pallet racking it is good practice to guard the aisle way from a potential hazard created by objects that may fall from the pallet rack. In these situations, load containment systems are added to the designated aisle way side of the pallet rack to prevent or control any item from falling off of the back of the rack system or potentially falling on and injuring a person in the aisle. Containment systems may also be placed between back to back installations to prevent items on one side of rack potentially pushing items off the adjacent rack.\nThere are two types of load containment systems for pallet racking: steel mesh containment panels and netting containment systems.\nNetting containment systems.\nLoad containment safety netting was originally adapted from cargo-based maritime netting used throughout the centuries for nautical trade and exploration. Safety netting has found widespread industrial use in load containment, driven in part by the post-war expansion of warehouse distribution systems. Netting types of varying break-strength and deflection allowances can be used within a load containment netting system. Widely accepted as an alternative to metal or other solid barrier systems, load containment safety netting provides a light weight, high-strength, easily customizable means to protect goods and personnel while allowing airflow, humidity control and clear visibility within sectioned containment areas.\nNetting containment systems are used on rack bays or gravity-flow rack channels to contain loose or falling objects. Palletized parts or boxes can become dislodged during bay loading. Rack netting containment systems can be placed vertically at the front, or pick face, and/or at the rear sides of racking systems prevent dislodged objects or full pallets from falling. Netting containment systems can be applied across multiple bays or as single bay units and secured by varying fasteners determined by frequency of access, load requirements and net or load sizes. Actuating systems can also be found in current netting containment systems to allow remotely operated rack bay access by use of pull cords or other means. In addition to vertical placement, horizontal netting can also be utilized in rack systems to protect against objects falling from one level to another or into tunnel areas, and to provide barriers between storage between and rack supports.\nSteel mesh containment panels.\nAs the distribution industry grew, alternative methods were sought for containing items dislodged from palletized storage while stored on pallet rack systems. Distributors found steel wire mesh panels were a viable alternative to netting containment systems. The following are the two types of steel mesh containment panels used for pallet racking:", "Engineering,_Manufacturing": 0.9999756813, "qwen": "Yes"}
{"id": "10823878", "revid": "44120587", "url": "https://en.wikipedia.org/wiki?curid=10823878", "title": "Swarf", "text": "Swarf, also known as chips or by other process-specific names (such as turnings, filings, or shavings), are pieces of metal, wood, or plastic that are the debris or waste resulting from machining, woodworking, or similar subtractive (material-removing) manufacturing processes. Swarf can be small particles (such as the gritty swarf from grinding metal or the sawdust from sawing or sanding wood); long, stringy tendrils (such as the springy chips from turning tough metals, or long shavings from whittling); slag-like waste (such as is produced within pipe during pipefitting work); or stone fragments and dust (as in masonry).\nSome of these terms are mass nouns (such as \"swarf\" and \"sawdust\") and some of them are count nouns (such as \"chips\", \"filings\", or \"shavings\").\nWood swarf is discussed at \"sawdust\".\nMetal swarf.\nChips can be extremely sharp and they can cause serious injuries if not handled correctly. It is not uncommon for chips flying off the cutter to be ejected with great force and to fly several yards.\nDue to its high surface area, swarf composed of some reactive metals can be highly flammable. Swarf may also spontaneously combust, especially if the swarf is coated with cutting oil. To extinguish swarf fires, a special fire extinguisher is needed, designed for fighting (metal) fires.\nWhen machining without coolant, swarf is usually very hot and can easily burn the machine operator. Machinists typically wear long pants, eye protection and other personal protective equipment for this reason.\nSome common engineering materials such as beryllium are hazardous when finely divided and appropriate measures should be taken to prevent exposure.\nFor ease of transport and handling, swarf may be compressed into \"bricks\". Metal swarf can usually be recycled.", "Engineering,_Manufacturing": 0.9999483824, "qwen": "Yes"}
{"id": "10826443", "revid": "42012606", "url": "https://en.wikipedia.org/wiki?curid=10826443", "title": "Rum Aladdin", "text": "Rum Aladdin was created in 2002 as a merger of Rum Metal Manufacturing Company and Rum-Aladdin Industries. Rum Aladdin is based in Jordan and is headquartered in Amman.\nThe company's stock is represented on the Amman Stock Exchange's ASE Weighted Index.\nOperations.\nThe company is composed of two merged manufacturing companies:\nRum Metal.\nRum Metal was established in 1972. It is a manufacturing company, producing tools and dies, performing sheet metal work, paint work and assembly work.\nRum Aladdin Industries.\nRum Aladdin Industries was established in 1981. It is involved with assembling gas heaters, TVss and electric heaters, water heaters, ladders, LCD.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "3835872", "revid": "45921974", "url": "https://en.wikipedia.org/wiki?curid=3835872", "title": "Coin (disambiguation)", "text": "A coin is a small, flat, round piece of metal or plastic that is used as money.\nCoin or Coins may also refer to:", "Engineering,_Manufacturing": 0.9999537468, "qwen": "Yes"}
{"id": "33862763", "revid": "1490139", "url": "https://en.wikipedia.org/wiki?curid=33862763", "title": "Stock depth", "text": "Stock depth is the total stock level build up in a supply chain, from the firm most upstream to the firm most downstream in the chain. The stock depth of the supply chain is calculated as the sum of the stock levels of all firms in a given supply chain.\nRelation with Lehman wave.\nStock depth is an important element in the behavior of the Lehman wave. \nIf the growth of an end market changes X% in a period t, the supply chain on average changes (1+0.5*Stock depth/t)*X%\nTherefore Y%= Stock Multiplier * X% = (1+SD/t) * X%.\nIf SD=1 and t=1 the multiplier for the average supply chain is . If the change is more sudden, say, within 6 months, the multiplier is 2, and if the change is very sudden, say within 3 months, the multiplier is as high as 3.\nIn a market with stable growth the effects are small. The further away a company is from the end market, the bigger the reaction. Firms that are far from the end market thus experience higher variations in growth. During a Lehman Wave, firms start active destocking. If the stock depth of a supply chain is large, the variation in growth becomes larger too, explaining why firms upstream in the supply chain experienced heavy growth variations during the Lehman Wave. During the Lehman Wave, companies upstream were hit more than companies downstream in the supply chain.\nWhen the sales of automobiles suddenly dropped in Q4 2008, the suppliers to the automotive producers not only had to absorb the decline itself, but also the corresponding re-active destocking in the whole supply chain that followed the declining end market. This is because the Automotive industry started active destocking.", "Engineering,_Manufacturing": 0.9983202219, "qwen": "Yes"}
{"id": "20501802", "revid": "45708962", "url": "https://en.wikipedia.org/wiki?curid=20501802", "title": "Press check (printing)", "text": "The printing press check is a step in the printing process. It takes place after a printing press is set up but before the print run is underway. \nWhile errors should be corrected during the Color Proofing and proofreading stages, the main purpose of a press check is to make sure that the color on press comes as close as possible to the color proof. Color proofs are valuable guides, but due to the inherent differences between color proofing techniques and printing itself, proofs will match the printed sheet with varying degrees of exactness.\nAreas that are commonly evaluated at a press check are:\nPost press check.\nWhile some printing jobs are delivered as printed, most printing is usually not complete until it is converted into a \"finished\" product. Post press includes various types of finish work such as trimming, embossing, foiling, die-cutting, scoring, folding and bindery. Post press checking can include:", "Engineering,_Manufacturing": 0.9999805689, "qwen": "Yes"}
{"id": "34482599", "revid": "302677", "url": "https://en.wikipedia.org/wiki?curid=34482599", "title": "Electrically conductive adhesive", "text": "An electrically conductive adhesive is a glue that is primarily used for electronics.\nThe electric conductivity is caused by a component that makes ca. 80% of the total mass of an electrically conductive adhesive. This conductive component is suspended in a sticky component that holds the electrically conductive adhesive together. The particles of the conductive component are in contact to each other and in this way make electric current possible.\nComposition.\nThe conductive component can be silver, nickel, copper or graphite. Other conductive materials are possible but unusual. The adhesive component can be a varnish, synthetic resin, or silicone. Variations in conductive component's type and concentration change the resistivity of the adhesive. A typical silver-based conductive adhesive such as that made by Electrolube contains ingredients in the following proportions:\nThey are specifically formulated in paste (micro-particles) for use in scanning electron microscopy (SEM) and other electron optical applications find use in producing or repairing printed circuit board (PCB) tracks, to paint-on an electrical screen, or to make electrical connections to non-solderable surfaces. ", "Engineering,_Manufacturing": 0.9920793772, "qwen": "Yes"}
{"id": "34486859", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=34486859", "title": "Saginaw 9.5-inch axle", "text": "The Saginaw 9.5-inch axle is an automotive axle manufactured by American Axle & Manufacturing, Inc. This differential has three major variants. A rear solid axle, a front solid axle and independent front suspension. General Motor's Saginaw Division started production of this axle in the late 1970s and all three variations are still in production today. The maximum GAWR for this axle is 6000 pounds.\nSaginaw 9.5-inch rear axle.\nThe Saginaw 9.5-inch axle began production in the late 1970s for GM's truck, van and suburban line up. It is a Semi-floating axle made for \"light duty\" 3/4 Ton vehicles.\nGM 9.25 IFS.\nThe GM 9.25 IFS has been the main front differential in Four-wheel drive 3/4 Ton and 1 Ton GM trucks since 1988. The Dana 60 solid axle front end was used selectively in trucks with a higher GVWR from 1988 to 1991. The original Saginaw 9.5 differential, ring and pinion were modified to work with the independent front suspension. The ring and pinion were also reverse-cut as well.\nAAM 9.25.\nThe AAM 9.25 solid axle was developed for 3rd generation Dodge Rams (3/4 and 1 Ton). The axle uses a modified Saginaw 9.5 differential, ring and pinion. The differential housing covers are identical except for one bolt hole at the 3 o’clock position. Model year 2010 and later Rams use larger universal joints than the 2003-2009 models.", "Engineering,_Manufacturing": 0.9979552627, "qwen": "Yes"}
{"id": "16864917", "revid": "545027", "url": "https://en.wikipedia.org/wiki?curid=16864917", "title": "Ultrasonic soldering", "text": "Ultrasonic soldering (U/S soldering) is a flux-less soldering process that uses ultrasonic energy, without the need for chemicals to solder materials, such as glass, ceramics, and composites, hard to solder metals and other sensitive components which cannot be soldered using conventional means.\nUltrasonic soldering is finding growing application in soldering of metals and ceramics from solar photovoltaics and medical shape memory alloys to specialized electronic and sensor packages. It has been used since 1955 to solder aluminum and other metals without the use of flux.\nProcess.\nUltrasonic soldering is a distinctly different process than ultrasonic welding. Ultrasonic welding uses ultrasonic energy to join parts without adding any kind of filler material while ultrasonic soldering uses external heating to melt filler metal materials, namely solders, to form a joint.\nUltrasonic soldering can be done with either a specialized soldering iron or a specialized solder pot. In either case the process can be automated for large-scale production or can be done by hand for prototyping or repair work. Initially, U/S soldering was aimed at joining aluminum and other metals; however, with the emergence of active solders, a much wider range of metals, ceramics and glass can now be soldered.\nUltrasonic soldering uses either ultrasonically coupled heated solder iron tips (0.5—10 mm) or ultrasonically coupled solder baths. In these devices, piezoelectric crystals are used to generate high frequency (20—60 kHz) acoustic waves in molten solder layers or batch, to mechanically disrupt oxides that form on the molten solder surfaces. The tips for ultrasonic soldering irons are also coupled to a heating element while the piezoelectric crystal is thermally isolated, in order to prevent degradation of the piezoelectric element. Ultrasonic soldering iron tips can heat (up to 450 °C) while mechanically oscillating at 20—60 kHz. This soldering tip can melt solder filler metals as acoustic vibrations are induced in the molten solder pool. The vibration and cavitation in the molten solder then permits solders to wet and adhere to many metal surfaces.\nThe acoustic energy created by the solder tip or ultrasonic solder pot works via cavitation of the molten solder which mechanically disrupts oxide layers on the solder layers themselves and on metal surfaces being joined.\nCavitation in the molten solder pool can be very effective in disrupting the oxides on many metals, however, it is not effective when soldering to ceramics and glass since they themselves are oxides or other non-metal compound that cannot be disrupted since they are the base materials. In the cases of soldering direct to glasses and ceramics, ultrasonic soldering filler metals need to be modified with active elements such as In, Ti, Hf, Zr and rare earth elements (Ce, La, and Lu). Solders when alloyed with these elements are called \"active solders\" since they directly act on the glass/ceramic surfaces to create a bond.\nAdoption.\nThe use of ultrasonic soldering is expanding, since it is clean and flux-less in combination with active solders being specified for joining assemblies where either corrosive flux can be trapped or otherwise disrupt operation or contaminate clean production environments or there are dissimilar materials / metals / ceramic / glasses being joined. To be effective in adhering to surfaces, active solder's own nascent oxide on melting need to be disrupted and ultrasonic agitation is well suited.", "Engineering,_Manufacturing": 0.9999167919, "qwen": "Yes"}
{"id": "16887435", "revid": "44127043", "url": "https://en.wikipedia.org/wiki?curid=16887435", "title": "Highpoint hitch", "text": "The highpoint hitch (or high post hitch) is a type of knot used to attach a rope to an object. The main feature of the hitch is that it is very secure, yet if tied as a slipped knot it can be released quickly and easily with one pull, even after heavy loading. The highpoint hitch is tied in the same manner as a slipped buntline hitch until the final turn, where they diverge.\nSecurity.\nThe highpoint hitch is very secure, since any load will tighten the turns against each other, at the same time tightening the grip on the working end.\nReleasing.\nTo release the slipped version of this knot, pull the working end in the direction of the load. This action pulls the two turns apart at the same time as releasing the draw-loop, and the whole knot simply falls apart.\nTying.\nTo tie the hitch around a pole, begin by passing the working end a half turn round the pole. Next, pass a half turn round the standing part. Then, pass a half turn round both the working end and the standing part, above the first turn (i.e. closer to the pole). Finally, push a bight of the working end through the middle of the hitch - between the two half turns, and between the standing part and the working end. Pull on the standing part to tighten, if necessary sliding the hitch snugly up against the pole.", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "42032211", "revid": "40581682", "url": "https://en.wikipedia.org/wiki?curid=42032211", "title": "Deep hole drilling (DHD) measurement technique", "text": "The deep hole drilling (DHD) measurement technique is a residual stress measurement technique used to measure locked-in and applied stresses in engineering materials and components. DHD is a semi-destructive mechanical strain relaxation (MSR) technique, which seeks to measure the distribution of stresses along the axis of a drilled reference hole. The process is unique in its ability to measure residual stresses at a microscopic level with a penetration of over , without total destruction of the original component. Deep hole drilling is considered \"deep\" in comparison to other hole drilling techniques such as centre hole drilling.\nTechnique overview.\nDHD involves drilling a hole through the thickness of the component, measuring the diameter of the hole, trepanning (cutting a circular slot around the hole) a core of material from around the hole and finally re-measuring the diameter of the hole. For engineering metals, the trepanning process is typically performed using electrical discharge machining (EDM) to minimise the introduction of further stresses during the cutting. The differences between the measured diameters before and after stress release enables the original residual stresses to be calculated using elasticity theory. An animated YouTube video explaining the DHD technique can be viewed here: YouTube: Deep Hole Drilling Technique.\nDHD procedure.\nFirstly, reference bushes are attached to the front and back surfaces of the component at the measurement location, to minimise \"bell-mouthing\" and assist with aligning the data sets during analysis. A reference hole is then drilled through a component; in engineering metals, a gun-drill is typically used due to the smooth and straight hole profile they produce. After drilling, the diameter of the reference hole is measured at frequent intervals along the full length and circumference of the measurement and reference bushes with an air probe. This is a thin rod with pressurised air forced from the end via two small holes at a normal to the reference hole axis. As the air probe is moved through the hole, changes in hole diameter will result in changes in pressure, which are detected with a calibrated transducer to convert the pressure change into a voltage. A cylinder (i.e. a core) of material containing the reference hole along its axis is then cut (trepanned) from the component using electro-discharge machining (EDM), in order to relax the stresses acting on the reference hole. Finally, the diameter of the reference hole is re-measured through the entire thickness of the cylinder and reference bushes, with the diameter measurements taken at the same locations as those measured prior to the trepanning.\nIncremental DHD technique (iDHD).\nIf high magnitude residual stresses (>60% yield stress) are present in the component then the DHD technique can be modified to account for plastic behaviour during the stress relief process. The risk of plastic deformation during stress relaxation is a problem in hole drilling techniques due to the approximately x3 stress concentrating factor of holes, effectively \"amplifying\" the stress relaxation and increasing the chance of yielding. Therefore, for iDHD, the procedure is changed to be performed \"incrementally\", with the core being cut (trepanned) in several steps of increasing depth and the diameter measurements being performed in between each step. The analysis then incorporates this sequence of incremental distortions for calculating the high magnitude residual stresses.\nInterpretation of the results.\nThe DHD method seeks to measure the distribution of stresses along the axis of the reference hole. The relationship between the original residual stresses acting on the reference hole and the measured changes in the hole diameter creates the basis of the analysis. The DHD technique uses an elastic analysis to convert the measured distortions of the reference hole into a residual stress profile. The accuracy of the results is dependent on sources of error in the measurement, but is also dependent on the elastic modulus of the material. A lower elastic modulus will result in larger distortions for a given stress release, meaning a higher measurement resolution and thus a greater achievable accuracy. The DHD technique has a nominal accuracy of ±10MPa for Aluminium, ±30MPa for Steel and ±15MPa for Titanium.\nAppraisal of the DHD technique.\nAdvantages and disadvantages of DHD, relative to other residual stress measurement techniques, are listed below.\nValidation.\nSeveral studies have been conducted to validate the DHD technique using samples with \"known\" stress states, by applying a defined load in the plastic range to create an internal stress state in a component, or by loading the component in the elastic range throughout the duration of the measurements.\nFor example, a beam component was plastically bent to introduce a known residual stress profile. These residual stresses were then measured using multiple residual stress measurement techniques including Neutron Diffraction, Slitting, Ring Core, Incremental Centre Hole Drilling, Deep Hole Drilling and Incremental Deep Hole Drilling, as well as modelled with finite element software to provide further numerical validation. The correlation between the results from techniques is strong, with DHD and iDHD displaying the same trend and magnitudes as both the numerical simulation and the other experimental techniques. The results from this comparison are shown in the Figure.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "5777287", "revid": "42964814", "url": "https://en.wikipedia.org/wiki?curid=5777287", "title": "Colonial (Shaw automobile)", "text": "The Shaw renamed the Colonial for 1921, was an American luxury automobile that was manufactured in Chicago, Illinois from 1920 until 1921. At the end of 1921 the Colonial was rebranded the Ambassador.\nHistory.\nWalden W. Shaw and John D. Hertz, owners of the Walden W. Shaw Livery Corporation, decided they wanted to expand into the production car market with a luxury car. Walden W. Shaw Livery Corporation owned the Yellow Cab Manufacturing Company. The new luxury automobile was introduced as a Shaw at the Hotel Congress during Chicago Automobile Show week in February 1920.\nWith Shaw taxicabs being so well known, using the Shaw name for a luxury car would not help sales so the name was changed to Colonial. This may have been no improvement, as several car makes had already been called Colonial. The Colonial was built on a 136-inch wheelbase and was offered as a 2, 4 or 7 passenger touring car priced at $5,000, .\nShaw and Hertz also change their mind about the engine. Initially it was a four-cylinder Rochester-Duesenberg. By July 1920, that unit was replaced by a Weidely twelve-cylinder to boost sales using the cachet of more cylinders. By the time of the Chicago Automobile Show of 1921, John Hertz was in complete charge of the company and he reintroduced the same car with a new Continental engine and a new name, the Ambassador.", "Engineering,_Manufacturing": 0.9993948936, "qwen": "Yes"}
{"id": "34684267", "revid": "21112944", "url": "https://en.wikipedia.org/wiki?curid=34684267", "title": "Contact protection", "text": "Contact protection methods are designed to mitigate the wear and degradation occurring during the normal use of contacts within an electromechanical switch, relay or contactor and thus avoid an excessive increase in contact resistance or switch failure.\nContact wear.\nA “contact” is a pair of electrodes (typically, one moving; one stationary) designed to control electricity. Electromechanical switches, relays, and contactors “turn power on” when the moving electrode makes contact with the stationary electrode to carry current. Conversely, they “turn power off” when the moving electrode breaks contact and the resulting arc plasma stops burning as the dielectric gap widens sufficiently to prevent current flow. Power relays and contactors have two primary life expectancy ratings: “mechanical life” is based on operating either without current or below the wetting current (i.e., “Dry”) and “electrical life” is based on operating above the wetting current (i.e., “Wet”). These different ratings are due to contacts being designed to compensate for the destructive arcing that naturally occurs between the electrodes during normal Wet operation. Contact arcing is so destructive that the electrical life of power relays and contactors is most often a fraction of their respective mechanical life.\nEvery time the contacts of an electromechanical switch, relay or contactor are opened or closed, there is a certain amount of contact wear. If the contact is cycling without electricity (dry), the impact of the contact electrodes a slightly deformed by the resulting cold forging. When the contact is operating under power (wet), the sources of the wear are the result of high current densities in microscopic areas, and the electric arc. Contact wear includes material transfer between contacts, loss of contact material due to splattering and evaporation, and oxidation or corrosion of the contacts due to high temperatures and atmospheric influences.\nWhile a pair of contacts is closed, only a small part of the contacts are in intimate contact due to asperities and low-conductivity films. Because of the constriction of the current to a very small area, the current density frequently becomes so high that it melts a microscopic portion of the contact. During the close-to-open (\"BREAK\") transition, a microscopic molten bridge forms and eventually ruptures asymmetrically, transferring contact material between contacts and increasing the surface roughness. This can also occur during the open-to-close (\"MAKE\") transition due to contact bounce.\nThe electric arc occurs between the contact points (electrodes) both during the transition from closed to open (\"BREAK\") and from open to closed (make) when the contact gap is small and the voltage is high enough. Heating due to arcing and high current density can melt the contact surface temporarily. If some of the melting material solidifies while the contacts are closed, the contact may stick closed due to a micro-weld, similar to spot welding.\nThe arc caused during the contact \"BREAK\" (\"BREAK\" arc) is similar to arc welding, as the \"BREAK\" arc is typically more energetic and more destructive. The arc can cause material transfer between contacts. The arc may also be hot enough to evaporate metal from the contact surface.\nThe high temperatures can also cause the contact metals to more rapidly oxidize and corrode.\nContacts reach end of life for one of two reasons. Either the contacts fail to \"BREAK\" because they are stuck (welded) closed, or the contacts fail to make (high resistance) because of contact corrosion or because excessive material is lost from one or both contacts. These conditions are the result of cumulative material transfer during successive switching operations, and of material loss due to evaporation and splattering.\nThere are additional mechanisms for stuck closed failures, such as mechanical interlocking of rough contact surfaces due to contact wear.\nProtection.\nThe degradation of the contacts can be limited by including various contact protection methods.\nBelow 2 Amperes, a variety of transient suppressing electronic components have been employed with varying success as arc suppressors, including: capacitors, snubbers, diodes, Zener diodes, transient voltage suppressors (TVS), resistors, varistors or in-rush current limiters (PTC and NTC resistors). However, this is the least effective method as these neither significantly influence the creation of nor suppress the arc between the contacts of electromechanical power switches, relays and contactors.\nHistorically, the two most common approaches to contact protection (above 2 Amperes) have been making the contacts themselves larger, i.e., a contactor and/or making the contacts out of more durable metals or metal alloys such as tungsten.\nThe most effective methods are to employ arc suppression circuitry including electronic power contact arc suppressors, solid state relays, hybrid power relays, mercury displacement relays and hybrid power contactors.", "Engineering,_Manufacturing": 0.9818224311, "qwen": "Yes"}
{"id": "34710385", "revid": "42208950", "url": "https://en.wikipedia.org/wiki?curid=34710385", "title": "Cofersa", "text": "Cofersa. Construcciones Ferrusola S.A. (Cofersa) was a Spanish motorcycle manufacturer between 1954 and 1962, using Hispano-Villiers engines of 125 and 200cc.\nOrigins.\nJosé Mercader, the manufacturer, had begun building auxiliary engines to install on bicycles. With this experience, he created Construcciones Ferrusola SA in 1953, to undertake the manufacture of motorcycles in Madrid.\nMotorcycles.\nThe first unit was put on sale in 1954, a 125cc model, emphasizing their functionality and quality of construction. Mechanical durability was ensured by the incorporation of Hispano-Villiers (Villiers manufactured under license in Spain) engines. With a conventional design, the make was highlighted by the robustness.\nDuring the first year the company produced only a hundred motorcycles, but in a short time the staff of employees exceeded the number of 100, to meet the demand.\nThe JM model appeared in 1957, incorporating stamped sheet metal and four-speed gearbox. In 1959 the model Helix went on sale, with stamped metal construction again, and a protective grid on the rear fenders, probably to make it easier for women to sit aside on the motorcycle without the skirts been tangled with rear wheel.\nAs a manufacturer of motorcycles, Cofersa activity ceased in 1962.", "Engineering,_Manufacturing": 1.0000047684, "qwen": "Yes"}
{"id": "10480723", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=10480723", "title": "Air carbon arc cutting", "text": "Air carbon arc cutting, also referred to as metal arc gouging, and previously as air arc cutting, is an arc cutting process where metal is cut and melted by the heat of a carbon arc. Molten metal is then removed by a blast of air. It employs a consumable carbon or graphite electrode to melt the material, which is then blown away by an air jet. \nThis process is useful for cutting a variety of materials, but it is most often used for cutting and gouging aluminum, copper, iron, magnesium, and carbon and stainless steel. Because the metal is blown away by the air jet, it does not need to be oxidized. This process differs from plasma cutting operations because in air carbon cutting an open, unconstricted arc is used, and the arc operates separately from the air jet.\nAir pressure for the jet usually varies from 60 to 100 psi (4-7 bar). The carbon electrode can be worn away by oxidation due to heat buildup. This can be reduced by coating the electrodes with copper.\nAs the sharpened carbon electrode is drawn along the metal, an arc forms and melts the metal. The air jet is used to blow away molten material. This can be dangerous, as the molten material can be blown substantial distances. The process is also very noisy. Metal removal is rapid, and when properly done, a smooth half-cylindrical cavity is created.", "Engineering,_Manufacturing": 0.9999957085, "qwen": "Yes"}
{"id": "62953727", "revid": "36389", "url": "https://en.wikipedia.org/wiki?curid=62953727", "title": "Gruppo TUO", "text": "Gruppo TUO is an Italian holding company dealing, through its subsidiaries, in the beverages and catering large-scale distribution sector. It was founded by Italian entrepreneur Antonino Faranda. The group owns the Italian discount supermarket chains Tuodì, InGrande and Fresco Market. In 2011 the Italian brewing company Peroni Brewery has agreed on the sale of the entire share capital of Doreca srl, the holding company of the Doreca distribution group, to Gruppo TUO. In 2015 Gruppo TUO was among the five major supermarket chains in Italy.", "Engineering,_Manufacturing": 0.9979147911, "qwen": "Yes"}
{"id": "31484016", "revid": "43224601", "url": "https://en.wikipedia.org/wiki?curid=31484016", "title": "Richard E. DeVor", "text": "Richard Earl DeVor (1944–2011) was a College of Engineering Distinguished Professor of Manufacturing and research professor at the University of Illinois at Urbana-Champaign. His research interests consist of mathematical modeling/simulation of material removal processes and mathematical modeling of the end milling/face milling processes. He attained his PhD at the University of Wisconsin-Madison. He died in July 2011.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "12067406", "revid": "8331790", "url": "https://en.wikipedia.org/wiki?curid=12067406", "title": "Anti-set-off spray powder", "text": "In printing, anti-set-off spray powder is used to make an air gap between printed sheets of paper. This enables the ink to dry naturally and therefore avoid the unwanted transfer of ink from one printed sheet to another. The problem can occur with most types of printing.\nAnti-set-off spray powder is generally made from natural starches from plants and vegetables. There remains a demand for soluble powders (sometimes known as vanished powders) based on natural sugars which are often used when the final printed sheet is to be varnished. In addition there is still a relatively small amount of powder made from minerals (e.g. Calcium Carbonate, rather than Talc) used in offset litho printing; however these mineral powders are not so popular because of the potential health implications and abrasive properties.\nSpray powder is used to separate printed sheets to enable air to naturally dry the printing ink. The diameter of the powder used is relative to the density (g/m2) of the stock (paper or board) being printed. For 150 g/m2 paper the ideal anti-set-off spray powder would be 15 μm in diameter, for 200 g/m2 20 μm, through to 70 μm for heavy board (700 g/m2).\nMost manufactures of spray powder offer both coated and uncoated powders. Uncoated powders are generally less expensive and are based on natural food-grade starches typically derived from corn (maize), wheat, semolina, potato, tapioca and rice depending on the diameter required. Coated powders use the same range of raw materials but are encapsulated with a minuscule amount of natural coatings which enable the powders to flow freely though the spray guns on sheet-fed offset-litho printing presses. Enhanced versions of these coatings are used to give specific electrostatic (anti-static) and hydrophobic properties.\nSpray powder is not used on rotary presses including rotary letterpress, web offset (often used for printing magazines), flexographic (often used for printing flexible packaging and labels) or gravure (often used for printing long-run catalogues). Similarly, spray powder is not generally used in sheet-fed (silk) screen-printing, ink-jet or toner based digital printing.\nIn the UK, many Carrom players use a version of anti-set-off spray powder from the printing industry which has specific electrostatic properties with particles of 50 micrometres in diameter.\nModern developments.\nAs health and safety has become more important to the environment and to the work forces, a small number of anti-set-off spray powder manufacturers had introduced highly clarified powders by 2007, in advance of EU legislation. This new generation of powders have typically less than 3% of particles of less than 10 μm and almost no particles below 5 μm which are generally regarded in the industry as dust. To put this in context typical human hair is 20 – 40 μm.\nThe printing industry regards anti-set-off spray powder as a necessary evil. Ideally printers would prefer not to use it, but it remains the only practical way to ensure a stack of printed paper at the end of a printing press does not set-off. In recent years there has been an emergence of printing presses which use inks that are cured (dried) with powerful UV lamps. As each sheet is individually dried there is no need for spray powder. However, as these machines require specialty inks which are much more expensive than conventional inks, and the UV lamps use a significant amount of energy, the vast majority of new sheet-fed presses sold in 2007 still used anti-set-off spray powder.\nOther uses.\nIn addition to its use in the printing and packaging industry, spray powder is also used in the manufacture of float glass to enable the large sheets to slide easily over each other. It is also used in the manufacture of plastic food wrap and similar products to help prevent pieces of plastic from sticking together because of static electricity.\nIn the UK, many carrom players use a version of anti-set-off spray powder from the printing industry which has specific electrostatic properties with particles of 50 micrometres in diameter.", "Engineering,_Manufacturing": 0.9998283982, "qwen": "Yes"}
{"id": "37686388", "revid": "4842600", "url": "https://en.wikipedia.org/wiki?curid=37686388", "title": "Sensors for arc welding", "text": "Sensors for arc welding are devices which – as a part of a fully mechanised welding equipment – are capable to acquire information about position and, if possible, about the geometry of the intended weld at the workpiece and to provide respective data in a suitable form for the control of the weld torch position and, if possible, for the arc welding process parameters.\nIntroduction.\nThe quality of a weld depends, besides the weld parameters which are important for the welding process (e.g. voltage, current, wire feed and weld speed) also mainly from the type of input of process energy and of the used filler material. The positioning of the torch exerts a direct influence on the material flow. The heat input for the melting of the component edges and the steady heat flow are, furthermore, directly connected with the torch guidance and exert substantial influence on the weld quality and on the resulting residual stresses. In fully mechanised and automated shielded gas welding, the inaccuracies of torch guidance, workpiece handling, groove preparation and thermal distortion are adding to the variations of the edge position and edge geometry. In fully mechanised welding, the information which is required for the weld quality is detected via sensors. Sensors are applied for checking the position of the component (detection of weld start and end of weld), for joint tracking and for the adaptation of the process parameters to changes of the joints/grooves. It is possible to use the sensors online (together/at the same time with the welding process) or offline (in a separate working step before welding). Sensors are mainly used in online joint tracking.\nPrinciples.\nAll physical principles which are capable to provide information about the position of an object are suitable to serve as the starting basis for a sensor function. The ambient conditions prevailing during arc welding and also the requirements which are made by fully mechanised equipments have, however, many restrictions as a consequence. Figure 1 depicts the system overview. The monitoring strategy of the sensor (process or geometry) has been chosen as the superordinate criterion, the further subdivision is orientated on the measuring principle. A further distinctive feature of sensor systems is their design. Leading sensors are, thus, marked by the fact that measuring point and joining point are not located in the same position. Here, the measuring and joining process are mainly running in sequence. For making position-relevant statements about the welding process, those systems require calibration of the relative position. If process-oriented sensors are used, the measuring point and the joining point are identical.\nWhat the measuring principles all have in common is the fact that through the evaluation of the sensor signal, geometrical information about the joint and its relative position to the measuring head is provided. The individual active principles allow different processing speed for acquiring the information.\nGeometry-oriented.\nGeometry-oriented sensors acquire their signals from the geometry of the groove or from an edge or area the course of which is in accordance with the groove.\nTactile sensors.\nElectric contact sensors for joint tracking and/or work piece measurement are representing one type of tactile sensors. The sensor makes electric contact with the workpiece, the electrically conductive workpiece is included into the measuring circuit of the sensor.\nThe mechanical contact sensors belong to the second category of the tactile sensors. The mechanical deflection of a scanning element which makes contact with the workpiece is evaluated.\nElectric contact sensors.\nFollowing a determined searching strategy, the electric contact sensor systems are scanning the weld start or other track points via contacting the work piece with parts/components which have been subjected to voltage (direct voltage of several ten Volt up to 1 KV, depending on material and surface) of the welding equipment (shielding gas nozzle, welding electrode, stylus, or similar.) This means the offline-measuring of the weld start, the part position or part geometry before welding. Knowing the scheduled path, a transformation of the track points in accordance with the measured conditions is carried out. In this case, corrective action is not carried out during the welding process.\nThermal.\nHere, the heat flow is measured with two thermo-couples which are arranged on the welding torch, the thermal flow is used for the side/lateral- and height control of the torch. The orientation of the torch towards the groove is detected via the comparison of the sensor temperature of the two thermo-couples. If the orientation of the torch is symmetrical, the difference of the radiated thermal flow equals to zero, so do the temperature differences of the thermo-couples. Dependent on the lateral misalignment of the torch the thermo-couples are subject to different heat flows, by the deformation of the arc and also by the changed position of the molten pool.\nMechanical contact.\nMechanical contact systems transform the deflection of the scanning element directly into electric control signals. The following transformer principles are differentiated:\nDue to the required distance of the acting/break points in one level, transformers which are equipped with micro-switches have a control hysteresis in the working point which has the consequence of a restricted reproducible accuracy. Electric displacement of the working point is not possible. The other, above-mentioned transformer systems (the use of optical systems is probably limited due to design reasons) produce analogous signals in proportion to the scanning element deflection and allow thus the error-proportional weld head tracking and also the electric working point displacement through the superordinate control, e.g. in multiple layer welding. The output signals of the most commonly used inductive measuring transformer systems are between 0 and 10 V DC, depending on the scanning element deflection (Figure 2).\nBoundary conditions.\nAny impairment of the electric contact between sensor scanning element and workpiece is, in the case of electric-contact sensors, problematic, e.g. welding spatters at the shielding gas nozzle, scale and rolling skin on the workpiece surface or through a wire electrode end which has molten spheroidally and has adherence of slag.\nWhen mechanical-contact sensors are used, the scanning elements must be adapted to the respective groove shapes. Butt welds with a square butt joint preparation must have a groove gap of more than 3 mm; in overlap joints the top plate must have a thickness of more than 3 mm.\nThe sensor must be mounted separately from the welding torch.\nThus, the groove scanning is mainly carried out in a leading position in front of the torch. If the welds are mainly straight, this adjustment is no problem. It is also possible to use scanning element arrays (e.g. fork callipers or separated scanning elements for height and lateral scanning which allow scanning in the torch level and thus weld scanning which is almost free from errors. Apart from the torch guidance along a weld groove, mechanical contact sensors can also be applied for detection of the weld start and end of the weld.\nOptical.\nOptical sensors belong to the group of non-contact measuring, geometry-oriented sensors (Figure 1). For information retrieval, the weld groove is scanned via a radiation detector which records the emitted optical radiation of the measured object. Semiconductor image sensors are applied for the detection of radiation. The optical measuring principles are differentiated into sensors with and without active structured lighting. If there is no active structured lighting, a camera is used for signal acquisition. The camera observes the workpiece and extracts the required information from the two-dimensional halftone picture. Active structured lighting means the application of a light source for the defined lighting of specified regions of the part. For the subsequent acquisition, single photo elements, lines or arrays can be used, depending on their design.\nOperating mode.\nFor optical measurement without active structured lighting, a camera is directed on the region of the weld groove and the scene of interest is observed directly. This is used, for example, for SA welding processes in order to provide the welder with a live photograph of the weld groove on the monitor.\nWe know two semiconductor technologies for image sensing. The CCD camera (CCD: Charged Coupled Device) is the best known, most widely spread camera type, it is also used in standard video cameras.\nIf a CMOS image sensor has been used, the high input dynamics allow, even with a burning arc, to record a usable image of the weld groove.\nThe method of optical measuring technique with active structured lighting, mainly generated by a laser with a defined wavelength, is often used for the automation of welding processes. It is differentiated between 1, 2 and 3-D measuring systems. Since measuring in the arc directly is not possible, a defined distance (advance) which depends on the type and size of the arc itself must be maintained.\nIf one-dimensional measuring systems are used, the distance from sensor to workpiece surface is determined. This is carried out via measurement of the running time. A further, frequently used method is laser triangulation (Figure 4).\nThe distance of the workpiece is determined from the known dimensions of the sensor and the triangulation angle α.\nThis type of one-dimensional optical distance measurement systems is widely used in the field of industrial automation technique and is therefore offered by many companies. In automated welding, they are often used for the detection of the part and/or groove position before the start of the welding process.\nThere are different types of design of the two-dimensionally measuring sensor systems. From the 1D triangulation sensor, the two-dimensional laser scanner can be derived from the oscillation movement. Here, the groove geometry is detected via a scanning movement transverse to the groove (Figure 5). This is mainly carried out via a movable mirror unit which is integrated in the sensor head.\nAs an alternative, an oscillating movement of the entire sensor head can be carried out, this is, however, only considered a special application of a one-dimensionally measuring system. An advantage of the laser scanner is that, with according processing speed, the lighting conditions can be adapted for every single point-shaped distance measurement which results in illumination uniformity. Moreover, due to the point-shaped illumination, the laser point is through the concentrated laser power and also through appropriate optical filters, compared with the interfering arc radiation, easier to detect by the detection element.\nThe light-section sensor avoids the disadvantage of moving parts in the sensor head (Figure 6). Here, the surface is not scanned pointwise, the entire geometry is, moreover, captured in one image. For this purpose, the point-shaped laser beam is expanded via an optics to a line which is projected onto the surface of the workpiece transverse to the groove in accordance with the scan line of the scanner. The laser line is, in accordance with the same geometrical principle of triangulation, again acquired with a detector element, this time, however, two-dimensionally. For the acquisition, CCD and CMOS cameras with the above-mentioned properties can be used.\nAs the output signal after the pre-processing of sensor signals with a laser scanner and light-section sensor, the so-called height profile of the measured groove geometry is achieved. It represents the surface of the workpiece along the section at the projected laser line.\n3 D measuring systems with active illumination are mainly using the light-section method in combination with the projection of several parallel laser lines. In doing so, each line generates a height profile. Through the arrangement of several lines along the weld groove, a further dimension is achieved which shows the change of the height profiles of the groove geometry. Through the number of the lines, the resolution in groove longitudinal direction is increasing, however, the data processing expenditure is also increasing. Similar to the projection of several parallel lines, the measurement via a projected circle or other geometrical figures on the workpiece surface is possible.\nBoundary conditions.\nWhat all optical measuring methods have in common is that the determined groove points must be transformed from the sensor coordinates of the cameras into machine and/or work piece coordinates. To this end, they must be calibrated on test work pieces before the welding process takes place and calibration matrices must be provided. Moreover, for the application of image processing algorithms, information about the groove profile must also be provided in advance. This is carried out via teaching of templates, input of geometrical parameters or teach-in via test work pieces. A more comprehensive image processing for 2 and 3 D sensor systems requires normally a PC system for the evaluation; this is why commercially available PC interfaces are used for data exchange, uniform sensor interfaces do, however, not yet exist.\nApplication problems.\nIn optical sensor systems, problems occur due to the operation principle through the scattered light of the open arc. Therefore, measuring in the working point directly is in most cases not possible when optical sensors are used, a certain advance/distance must be maintained. Further process trouble stems from weld spatters which may exert a negative influence on the detection results. Screening systems between sensor and torch provide a remedy to a certain extent. The direct observation of the arc with special cameras for process monitoring remain an exception.\nThe running of the sensor in front of the arc causes the limited accessibility of corners in the parts. In order to reduce this problem, a design/structure which is as compact as possible and a short advance distance are most important. The pre-defined orientation of the sensor is, moreover, restricting the working space of the robot. For untroubled operation of the optical components also stronger soiling/impurification (dust and deposition of weld fume particles) should be avoided, if possible. Exchangeable protective glasses and safety screens in the form of compressed air curtains provide a remedy. The quality of the surface which is to be measured has substantial influence on the measuring result. If the surface is strongly reflecting, unwanted reflection and faulty measurements may occur, lustreless surfaces are less difficult. Ever-changing surface qualities also lead to problems.\nSince optical systems are equipped with semiconductor detectors and comprehensive electronics, it is most important to pay attention to safe electro-magnetic screening. This applies to the sensor, the image processing unit and the connecting cables thereof. Sensor systems with active laser illumination are reacting particularly sensitive to strong temperature fluctuations since the emitted light wavelength of the used laser diodes depends on the temperature of the laser. If the ambient temperature and thus the wavelength of the active illumination are changing, the light is no longer capable to penetrate through the narrow-band optical filter to the photodetector. Therefore, appropriate screening against the welding process or the cooling of the sensor head is required. Depending on the applied laser power, particular caution must be taken when sensors with active illumination are applied. The wavelength of the applied systems are often in the field of vision, which means the classification into the hazard classes 3A and 3B. The respective accident prevention regulations must be strictly adhered to.\nThe application of optical sensors demands the consideration of following points:\nInductive.\nInductive sensors evaluate the attenuation of a high-frequency electro-magnetic field which has been generated by eddy currents in the work piece. The application of single-coil design types allows side or height correction. Multiple-coil sensors allow correction in two coordinate directions and, moreover, influence on the weld torch orientation.\nCapacitive.\nCapacitive sensors measure the capacity between the work piece and an electrically conductive plate with small dimensions. They offer the possibility of distance measurement in media with unchanged dielectricity constant.\nProcess-oriented.\nProcess-oriented sensors are acquiring their signals from the primary or secondary process parameters.\nArc sensors are using the primary process parameters (weld current and/or voltage) of one moving or two unoscillated arcs for the generation of height and side/lateral correction signals.\nThese sensors require, of course, also a scannable groove geometry; the measuring and the joining point are, however, compared with geometry-oriented sensors, located in the same position.\nArc.\nStable working points in arc welding are developing as interface between process characteristic and power source characteristic (Figure 7). The process characteristic specifies the connection between a stable arc voltage and the appropriate current rating of the process under constant boundary conditions. A family of characteristics is achieved via the variation of the arc length / torch distance.\nIn TIG welding.\nTIG welding belongs to the welding processes with non-melting electrode. Therefore, the process characteristic is often designated as arc characteristic. A direct change of the working distance is compensated via the length of the arc. As a result, the arc resistance is changing. Short arcs have a lower electric resistance than long arcs.\nIn TIG welding, typically power sources with a steeply drooping characteristic are applied. A change of the arc length leads, therefore, directly to the change of the process voltage. A comparative measurement allows the determination of the distance to the workpiece.\nIn GMA welding.\nIn GMA welding, the process characteristic in the voltage-current diagram is a result from the interaction of the electric properties of the wire stick-out and of the arc. In principle, stable working points are achieved through the application of suitable power source characteristics or through super-imposed control strategies.\nThere is a stable equilibrium in point 1 of Figure 8 where the energy which has been input into the process is sufficient for the melting of the continuously fed wire electrode. In the case of a rapid change of distance, the arc compensates the length change, point 2. The lower resistance of the short arc brings about the increase of the current intensity which leads to the faster melting of the wire stick-out until again a stable working point is reached, point 3. This compensation process takes approximately between 100 and 200 ms. The arc sensor evaluates the remaining change in current intensity between point 1 and point 3 in order to achieve a distance-proportionate parameter. In principle, this evaluation concept is also applicable to pulsed arc welding. The concept which has been specified above is, in the case of most arc sensors, extended by the transversal scanning of the groove geometry. The deflection of the process to the fusion faces allows the comparative measurement of the torch distance. By calculating the difference of the distance values, the lateral positioning of the torch can be evaluated. The mean value of both distance values indicates the height of the torch above the groove. Different concepts are applied for the deflection (Figure 9). Mechanical oscillation is most widely spread and is frequently used, especially with robots. Basically, fast deflectory systems, e.g. with magnetic or rotatory deflection offer the improvement of the signal rate and the signal quality, a higher apparatus expenditure must, however, be calculated when these systems are used. In double-wire technique, both fusion faces are scanned at the same time with one wire each.\nBoundary conditions.\nArc sensors are evaluating the stable working points in arc welding. Disturbance variables of the process must be compensated via suitable filtering and evaluation strategies which are not susceptible to disturbances.\nIn the case of a simultaneous height and side control attention must be paid to the fact that only those groove geometries are suitable for arc sensor systems whose geometry allows the lateral position determination via comparative measurement of the fusion faces. V-type welds and fillet welds are suitable without any restrictions. Square butt welds without gap are not suitable for side/lateral control. Commercially available arc sensors are, so far, not applicable for aluminium materials.\nSecondary process parameters.\nSensor types which are observing the molten pool are restricted in their applicability range by the fact that molten pool size and arc radiation are dependent on geometrical factors, e.g. material density or composition (alloying constituents). The optical observation of the molten pool region determines changes of the molten pool contour. The deflection from a contour which is defined as “ideal” is interpreted as malposition or as a change of the process behaviour and is compensated subsequently.\nSpectral analysis.\nThe spectral analysis of the process signals compares the emission spectres of the arc or of the molten pool with assumed ideal values. Deflections point to a changed chemical composition or to energetic changes of the process zone.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "37700713", "revid": "5723718", "url": "https://en.wikipedia.org/wiki?curid=37700713", "title": "Brake tester", "text": "There are at least three different types of brake tester used to calculate the braking efforts and efficiencies of a motor vehicle:\nRoller brake testers.\nA roller brake tester is a method of allowing the dynamic assessment of the braking system of a motor vehicle, whilst the vehicle itself is in a static condition. This type of brake tester is normally used in UK garages when used as part of an inspection lane for the MOT test.\nRoller brake testers consist of a mechanical floor unit which contains electrical motors, two independent sets of three measuring rollers, brake force transducers and additional safety sensors. \nThe driving rollers operate at a low (known) speed using a gearbox and motor arrangement and during a test measurements of the maximum braking force are taken by applying the vehicle brakes which induces a reaction force on the electric motor itself. An electric transducer with strain gauges then measures the individual induced forces which are acting during the deceleration phase in order to calculate the individual braking forces for each wheel.\nIn order to minimize any inaccuracy and variation in the measurement, the roller diameter is sufficiently large to reduce the effects of the mechanical relaxation, or flexing, of the tire itself. A special coating on the rollers is designed to be very wear resistant and provide good friction values, both in wet and dry conditions.\nA third smaller roller, on each side between the driving rollers, has two functions: The first is to detect if a vehicle is present in the roller bed (a built in safety device to prevent the motor from starting up unless a vehicle is in the brake tester), the second function is to detect when and if tyre slippage occurs in order to make the measurement before a maximum, predefined value of time passes.\nDuring the test, the computer measures the brake force values and the system will calculate the imbalance between the left and right brake forces of an axle, as well as the brake efficiency of the service brake and the parking brake provided that a vehicle weight is either inputted manually or by using an integrated weighing system.\nPlate brake testers.\nA plate brake tester is a method of measuring a vehicles braking system in a dynamic test. The unit consists of two moving parallel plates mounted on force transducers. A measurement of the braking force is made when a vehicle passes over the plates and then applies its brakes. The braking action causes the individual plates to ‘slip’ forwards allowing a calculation of braking force to be made. Brake imbalance between the left and right hand side can also be measured by the differences in voltage measured on each of the force transducers under the chassis. Due to the nature of it dynamic operation, plate brake testers are far less common than roller brake testers in UK garages although they are also an extremely accurate method of measurement.\nThe extremely accurate plate brake method of measuring a vehicle's braking performance in countries such as Australia and New Zealand is increasingly becoming a far more popular alternative to basic decelerometers due to not only accuracy, measurement speed, and the ease of use, but predominately the greatly improved safety offered by removing the need for vehicle inspectors to brake test vehicles on public roads amongst other road users .\nDecelerometers.\nA decelerometer is a hand held device for measuring dynamic braking forces during a vehicle road test. A vehicle decelerometer operates as if it were, and it could also be known as, an accelerometer as it calculates braking efficiency by using those forces captured during a vehicle's deceleration. A decelerometer is a basic method by which braking effort can be accessed quickly and easily but it is generally used as an indicator to acceptable brake performance. Low efficiency readings should lead to further investigation on either a plate brake tester or a roller brake tester. ", "Engineering,_Manufacturing": 0.995971024, "qwen": "Yes"}
{"id": "1081644", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=1081644", "title": "Quill drive", "text": "A quill drive is a mechanism that allows a drive shaft to shift its position (either axially, radially, or both) relative to its driving shaft. It consists of a hollow driving shaft (the quill) with a driven shaft inside it. The two are connected in some fashion which permits the required motion.\nExamples.\nDrill press.\nOne example of a quill drive is found in a drill press where the quill allows the chuck to move vertically while being driven rotationally.\nRailroad locomotive.\nQuill drives have been extensively used in railroad electric locomotives to connect between frame-mounted traction motors and the driven wheels. The two are linked by a flexible drive which allows a degree of radial motion and possibly a small amount of axial motion. This allows the motors to be mounted on top of the suspension system, moving independently of the wheels. This smooths the drive from the motors and isolates them from mechanical shock. This also decreases the unsprung weight borne directly by the wheels, thus decreasing wear on the track.\nQuill drives were used by many electric locomotives in the United States, particularly those of the Pennsylvania Railroad—their long-lasting GG1 design being perhaps the best known. Many locomotives built in France, Germany, Italy and Poland used quill drives as well, allowing higher locomotive speed. The English Electric–built NZR ED class used a quill drive, but was found to be hard on the track.", "Engineering,_Manufacturing": 0.9999884367, "qwen": "Yes"}
{"id": "1085127", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1085127", "title": "Wafer testing", "text": "Wafer testing is a step performed during semiconductor device fabrication after BEOL process is finished. During this step, performed before a wafer is sent to die preparation, all individual integrated circuits that are present on the wafer are tested for functional defects by applying special test patterns to them. The wafer testing is performed by a piece of test equipment called a wafer prober. The process of wafer testing can be referred to in several ways: Wafer Final Test (WFT), Electronic Die Sort (EDS) and Circuit Probe (CP) are probably the most common.\nWafer prober.\nA wafer prober is a machine used for integrated circuits verification against designed functionality. It's either manual or automatic test equipment. For electrical testing a set of microscopic contacts or probes called a probe card are held in place whilst the wafer, vacuum-mounted on a wafer chuck, is moved into electrical contact. When a die (or array of dice) have been electrically tested the prober moves the wafer to the next die (or array) and the next test can start. The wafer prober is usually responsible for loading and unloading the wafers from their carrier (or cassette) and is equipped with automatic pattern recognition optics capable of aligning the wafer with sufficient accuracy to ensure accurate registration between the contact pads on the wafer and the tips of the probes.\nFor today's multi-die packages such as stacked chip-scale package (SCSP) or system in package (SiP) – the development of non-contact (RF) probes for identification of known tested die (KTD) and known good die (KGD) are critical to increasing overall system yield.\nThe wafer prober also exercises any test circuitry on the wafer scribe lines.\nSome companies get most of their information about device performance from these scribe line test structures.\nWhen all test patterns pass for a specific die, its position is remembered for later use during IC packaging. Sometimes a die has internal spare resources available for repairing (i.e. flash memory IC); if it does not pass some test patterns these spare resources can be used. If redundancy of failed die is not possible the die is considered faulty and is discarded. Non-passing circuits are typically marked with a small dot of ink in the middle of the die, or the information of passing/non-passing is stored in a file, named a wafermap. This map categorizes the passing and non-passing dies by making use of bins. A bin is then defined as a good or bad die. This wafermap is then sent to the die attachment process which then only picks up the passing circuits by selecting the bin number of good dies. The process where no ink dot is used to mark the bad dies is named substrate mapping. When ink dots are used, vision systems on subsequent die handling equipment can disqualify the die by recognizing the ink dot.\nIn some very specific cases, a die that passes some but not all test patterns can still be used as a product, typically with limited functionality. The most common example of this is a microprocessor for which only one part of the on-die cache memory is functional. In this case, the processor can sometimes still be sold as a lower cost part with a smaller amount of memory and thus lower performance. Additionally when bad dies have been identified, the die from the bad bin can be used by production personnel for assembly line setup.\nThe contents of all test patterns and the sequence by which they are applied to an integrated circuit are called the test program.\nAfter IC packaging, a packaged chip will be tested again during the IC testing phase, usually with the same or very similar test patterns. For this reason, it may be thought that wafer testing is an unnecessary, redundant step. In reality this is not usually the case, since the removal of defective dies saves the considerable cost of packaging faulty devices. However, when the production yield is so high that wafer testing is more expensive than the packaging cost of defect devices, the wafer testing step can be skipped altogether and dies will undergo blind assembly.", "Engineering,_Manufacturing": 0.9999952316, "qwen": "Yes"}
{"id": "69922", "revid": "1158095691", "url": "https://en.wikipedia.org/wiki?curid=69922", "title": "Original equipment manufacturer", "text": "An original equipment manufacturer (OEM) is generally perceived as a company that produces non-aftermarket parts and equipment that may be marketed by another manufacturer. It is a common industry term recognized and used by many professional organizations such as SAE International, ISO, and others.\nHowever, the term is also used in several other ways, which causes ambiguity. It sometimes means the maker of a system that includes other companies' subsystems, an end-product producer, an automotive part that is manufactured by the same company that produced the original part used in the automobile's assembly, or a value-added reseller.\nAutomotive parts.\nWhen referring to auto parts, OEM typically refers to the manufacturer of the original equipment, that is, the parts which are then subsequently assembled and installed during the construction of a new vehicle. In contrast, aftermarket parts are those made by companies other than the OEM, which might be installed as replacements or enhancements after the car comes out of the factory. For example, if Ford used Autolite spark plugs, Exide batteries, Bosch fuel injectors, and Ford's own engine blocks and heads when building a car, then car restorers and collectors consider those to be the OEM parts. Other-brand parts would be considered aftermarket, such as Champion spark plugs, DieHard batteries, Kinsler fuel injectors, and BMP engine blocks and heads. Many auto parts manufacturers sell parts through multiple channels, for example to car makers for installation during new-vehicle construction, to car makers for resale as automaker-branded replacement parts, and through general merchandising supply chains. Any given brand of part can be OEM on some vehicle models and aftermarket on others.\nComputer software.\nMicrosoft is a popular example of a company that issues its Windows operating systems for use by OEM computer manufacturers via the bundling of Microsoft Windows. OEM product keys are priced lower than their retail counterparts, especially as they are purchased in bulk quantities, although they use the same software as retail versions of Windows. They are primarily for PC manufacturer OEMs and system builders, and as such are typically sold in volume licensing deals to a variety of manufacturers (Dell, HP, ASUS, Acer, Lenovo, Wistron, Inventec, Supermicro, Compal Electronics, Quanta Computer, Foxconn, Pegatron, Jabil, Flex, etc.). These OEMs commonly use a procedure known as System Locked Pre-installation, which pre-activates Windows on PCs that are to be sold via mass distribution. These OEMs also commonly bundle software that is not installed on stock Windows on the images of Windows that will be deployed with their PCs (appropriate hardware drivers, anti-malware and maintenance software, various apps, etc.).\nIndividuals may also purchase OEM \"system-builder\" licenses for personal use (to include virtual hardware), or for sale/resale on PCs which they build. Per Microsoft’s EULA regarding PC manufacturers and system-builder OEM licenses, the product key is tied to the PC motherboard which it is initially installed on, and there is \"typically\" no transferring the key between PCs afterward. This is in contrast to retail keys, which may be transferred, provided they are only activated on one PC at a time. A significant hardware change will trigger a reactivation notice, just as with retail.\nDirect OEMs are officially held liable for things such as installation/recovery media, and as such were commonly provided until the late-2000s. These were phased out in favor of recovery partitions located on the primary storage drive of the PC (and available for order from the manufacturer upon request) for the user to repair or restore their systems to the factory state. This not only cut down on costs, but was also a consequence of the gradual obsolescence and phasing out of optical media from 2010 onward. System builders also have a different requirement regarding installation media from Direct OEMs. \nWhile a clean retail media of Windows can be installed and activated on these devices with OEM keys (most commonly using the SLP key that's embedded in to the system firmware already), actual OEM recovery media that was created by the PC manufacturer (not system-builder, nor retail Windows versions) typically only works on the PC model line that was designed for it. For example, a recovery disc/USB for a Toshiba Satellite P50-B will only work on that model, and not a Satellite S55T.\nEconomies of scale.\nOEMs rely on their ability to drive down the cost of production through economies of scale. Using an OEM also allows the purchasing company to obtain needed components or products without owning and operating a factory.\nMisuse.\nSome companies mistakenly use the title OEM when referring to Custom Machine Builders, Systems Integrators, and other companies that design and build custom factory automation. Two such companies include Keyence and Omron.", "Engineering,_Manufacturing": 0.999986887, "qwen": "Yes"}
{"id": "11323810", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=11323810", "title": "Folding carton", "text": "The folding carton created the packaging industry as it is known today, beginning in the late 19th century. The process involves folding carton made of paperboard that is printed, laminated, cut, then folded and glued. The cartons are shipped flat to a packager, which has its own machinery to fold the carton into its final shape as a container for a product. An example of such a carton is a cereal box.\nSome styles of folding cartons can be made of E-flute or micro-flute corrugated fiberboard.\nInvention and development.\nIn the 1840s, cartons were made by hand and held together with tacks and string, and used only for expensive items (such as jewellery). Although Charles Henry Foyle is described by some as the \"inventor\" of the paper carton, mass production of the cartons was invented, partly by accident, at the Robert Gair Company in Brooklyn, New York. Machinery at the end of the press had been set up carelessly by a pressman, and machinery cut through the material. This ruined the press but gave them an idea: printing and cutting could be done with one machine. Previously, cutting of printed cardboard had been done manually. From the mistake in 1879, Gair developed a process for mass production of boxes. In 1897, the National Biscuit Company (Nabisco) became the first large company to adopt the new cartons, for Uneeda Biscuits. Other manufacturers soon followed. With inexpensive packaging now even common items could be placed in a showy carton and each carton became its own advertisement. The product was also protected, and the contents had a longer shelf life. This trend was to continue with force, through the 20th century. This could be seen as a contributing factor in the so-called 'throwaway' culture of America. The environmental impact of product packaging has gained attention from consumers and businesses alike, and this awareness has created a steady trend since the mid to late 1990s, on the part of manufacturers, to use recycled material and/or reduce overall materials usage.\nProduct characteristics.\nFolding cartons are now a $110 billion industry. Typically, cylinder board made from pulp from reprocessed scrap paper is used for most packages. Cartons for food are made from a higher grade and lighter solid sulfate board with plastic coating. Because of the limitations of cutting machinery, the thickness of the board is limited to 0.81 mm (0.032 in), and folding cartons are generally limited to holding a few pounds or kilograms of material.\nFolding cartons are frequently tall and wide but very thin. For example a typical breakfast cereal box has a poor material to volume ratio and is very inefficient; it is wasteful and can be considered overpackaging. Package designers are aware of this opportunity to save packaging costs, materials, and waste but marketing and merchandising people want the “billboard” style package for advertising and graphics. An optimized folding carton would use much less paperboard for the same volume of cereal, but with reduced room for graphics.\nOpening.\nOpening a carton can be accomplished by opening an access flap, cutting, use of tear tapes or perforations.", "Engineering,_Manufacturing": 0.9999830723, "qwen": "Yes"}
{"id": "35570864", "revid": "14965160", "url": "https://en.wikipedia.org/wiki?curid=35570864", "title": "Measurement-assisted assembly", "text": "Measurement-assisted assembly (MAA) is any method of assembly in which measurements are used to guide assembly processes. Such processes include:\nMeasurement-assisted assembly is typically used for large structures such as aircraft and steel fabrications. It can be used to improve production rates, reduce reworking and increase flexibility for processes where manual reworking during assembly is required to maintain assembly form and component interface conditions. This type of approach generally offers no advantages where part-to-part interchangeability can already be achieved.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1805981", "revid": "9332553", "url": "https://en.wikipedia.org/wiki?curid=1805981", "title": "Just in sequence", "text": "Just in sequence (JIS) is an inventory strategy that matches just in time (JIT) and complete fit in sequence with variation of assembly line production. Components and parts arrive at a production line right in time as scheduled before they get assembled. Feedback from the manufacturing line is used to coordinate transport to and from the process area. When implemented successfully, JIS improves a company's return on assets (ROA), without loss in flexibility, quality or overall efficiency. JIS is mainly implemented with car manufacture.\nJIS is sometimes called In-Line Vehicle Sequencing (ILVS).\nJust in sequence is just in time.\nJust in sequence (JIS) is just one specialised strategy to achieve just in time (JIT). The process concept of JIT sees buffers at the production line as waste in capital bound. The aim is to eliminate buffers as much as possible at the expense of stability when disturbances arise. Just In Sequence is one of the most extreme applications of the concept, where components arrive Just In Time and sequenced for consumption.\nThe sequencing allows companies to eliminate supply buffers as soon as the quantity in component part buffers necessary is reduced to a minimum. If not sequencing according to scheduled variety of production, all required components must be stocked in buffers. For flexible production lines, such as a modern automotive assembly line, the variety is an option to produce directly on customer orders. As soon as the next order arrives at the work center, the scheduler distributes the supply orders inline with the production sequence of the final production line.\nDisplacement of buffers upwards to suppliers.\nHowever, with JIS the buffer quantities are displaced upward in material flow to the components suppliers. It is a misinterpretation of JIS to assume that all buffers will be eliminated. Hence just the cost for buffer inventory becomes re-allocated to the producers of the supplies. Sequencing eliminates buffers in the final assembly line by consolidating all similar components into distributed and sequenced buffers, which partly reside on the paths of transport to final assembly. This strategy thus reduces the line-side inventory buffer. However, the effect is worse when the sequence does not get correctly scheduled upwards or when the transport line gets congested.\nIntroduction of JIS concepts.\nJust In Sequence processes are typically implemented only after the company has achieved a high degree of competency on Just In Time processes. The first step for the organization is to implement JIT processes to synchronize all manufacturing and material departments inside the plant and to collaborate with suppliers, customers, and sub-contractors to reduce inventory buffers to within a few hours. This process typically uncovers deep manufacturing and logistic issues that are not easy to overcome (see JIT Implementation for more details). The manufacturing company can only benefit from sequencing items once these problems have been resolved successfully and components are delivered Just In Time.\nSequencing can be implemented in a Just In Time supply operation at many levels, bringing ever-higher inventory reduction and financial benefits:\nImplementing JIS concepts.\nJust In Sequence implementations introduce a number of new process requirements on top of Just In Time practices. A production sequence or final assembly sequence must be shared upwards to suppliers and sub-contractors. Feedback to customers must be organized according to the scheduled output to earn all positive financial effects. For these and other reasons, the actual production sequence must be \"broadcast\" out to all relevant parties once it is firm. This \"broadcast\" can be done over the phone, paper, email, or other automated IT system. UN/EDIFACT supports an EDI message standard called DELJIT as one standardized way to communicate this information.\nOnce the sequence is broadcast, each party must immediately take action to deliver sequenced parts in time. In many cases the turn-around time from broadcast to final assembly is less than 2 hours, with some components required in 30 minutes or less. With this time frame, there is little room for errors. In addition, quality inspection and poka-yoke must be implemented in the sequencing step to guarantee that the sequenced components match the assembly sequence perfectly. In many cases, suppliers must manage periodic sequence reversals, for example, when loading racks into a truck, since the first rack into the truck is the last one to come out. Employees and systems must also properly manage exceptional scenarios, such as re-processing damaged items after initial sequencing, skipping slots for scrapped items, etc. Just In Sequence implementations can only be successful if all of these processes are implemented correctly and all people involved understand what is at stake.\nLimitations.\nIn many manufacturing operations, the actual production sequence cannot be planned ahead of time with enough certainty to enable sequencing. The main reason is that some manufacturing processes require re-work frequently so that a scheduled sequence becomes irrelevant. For example, painting operations in an automotive plant can have re-work levels of up to 20% (USA, Southern Europe).\nReferences.\nStephan M. Wagner and Victor Silveira-Camargos, 2009, \"Decision model for the application of just-in-sequence\", in: Decision Sciences Institute Proceedings of the 40th annual conference, New Orleans, USA.", "Engineering,_Manufacturing": 0.999566257, "qwen": "Yes"}
{"id": "29082127", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=29082127", "title": "Ellington Electronics Technology Group", "text": "Ellington Electronics Technology Group 依頓電子科技股份有限公司 (simply known as Ellington PCB or Eton) is one of the leading printed circuit board (PCB) manufacturers in China. It is a Hong Kong based company which is listed on the Shanghai Stock Exchange on 1 July 2014. In Year 2018, the company was ranked Top 10 in China and 41st in the world by revenue.\nHistory.\nEllington was founded in March 2000, principally engaged in the manufacture and sale of high precision and density 2/L to 20/L printed circuit board. With in-house surface finishing of Organic Solderability Preservative (OSP), Lead-Free Hot Air Solder Leveling (HASL), Immersion Gold / Silver / Tin. It manufactures for over 400 customers worldwide. Ellington's world ranking jumped from 88th in 2005 to 41st in 2018.\nOperations.\nThe company's headquarter and production facilities are located in Zhongshan City, Guangdong Province, China. The 4 storey manufacturing plant has a total area of 2,600,000 ft2. Ellington focusing on production quality management and control, with the mission of \" Quality Is Life \", the company is ISO/TS16949, ISO 9002, ISO 14001 and OHSAS 18001 certified. After the completion of its 3rd stage capacity expansion, the company currently generates an output of 4,200,000 ft2 (390,600 m2) per month and currently employs more than 6,500 people.\nEllington also has a logistic facility and administration office located in Tsuen Wan, Hong Kong.\nThe company produces multilayered rigid PCBs that are used in various electronic equipment worldwide including consumer electronics, telecommunication, computer and Computer Peripherals, automotive industry, automation, power supply and electronic test equipment.\nFuture.\nEllington has completed the 4th Stage of capacity expansion, generating a further 500,000 ft2 capacity for Automotive Industry only in an isolated production plant. A total production output of 7,000,000 ft2 multilayer PCB will be generated by the 5th Stage of capacity expansion plan after listing on Shanghai Stock Exchange.\nMajor Customer Base.\nApple, Bose Corporation, Continental AG, Delphi Technologies, Flextronics, Huawei, Jabil Circuit, Lite-On, Preh, Robert Bosch GmbH, Wistron Corporation, Valeo and 200+ others. ", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "10571090", "revid": "13674103", "url": "https://en.wikipedia.org/wiki?curid=10571090", "title": "Tailstock", "text": "A tailstock, also known as a foot stock, is a device often used as part of an engineering lathe, wood-turning lathe, or used in conjunction with a rotary table on a milling machine.\nIt is usually used to apply support to the longitudinal rotary axis of a workpiece being machined. A lathe center is mounted in the tailstock, and inserted against the sides of a hole in the center of the workpiece. A tailstock has a Dead Center, while headstock has Live Center. A Tailstock is particularly useful when the workpiece is relatively long and slender. Failing to use a tailstock can cause \"chatter,\" where the workpiece bends excessively while being cut.\nIt is also used on a lathe to hold drilling or reaming tools for machining a hole in the work piece. Unlike drilling with a drill press or a milling machine, the tool is stationary while the workpiece rotates. Holes can only be cut along the axis that the workpiece is set to spin.\nUsually, the entire tailstock is moved to the approximate position that it will be needed by manually sliding it along its ways. There, it is locked in place and the tool mounted to it is moved with a leadscrew to the exact position where it is needed. When a cutting tool such as a drill bit or reamer is used, the feed is done with this leadscrew. The extendible portion of the tailstock is called the barrel, and usually has a Morse taper mount in the end of it to secure the drill or reamer. If the work is heavy the drill may be further secured from turning with a lathe dog as shown in the photo.", "Engineering,_Manufacturing": 1.0000033379, "qwen": "Yes"}
{"id": "10571853", "revid": "33594889", "url": "https://en.wikipedia.org/wiki?curid=10571853", "title": "Centerless grinding", "text": "Centerless grinding is a machining process that uses abrasive cutting to remove material from a workpiece. Centerless grinding differs from centered grinding operations in that no spindle or fixture is used to locate and secure the workpiece; the workpiece is secured between two rotary grinding wheels, and the speed of their rotation relative to each other determines the rate at which material is removed from the workpiece.\nCenterless grinding is typically used in preference to other grinding processes for operations where many parts must be processed in a short time.\nWorking principle.\nIn centerless grinding, the workpiece is held between two wheels, rotating in the same direction at different speeds, and a work-holding platform. One wheel, known as the grinding wheel (stationary wheel in the diagram), is on a fixed axis and rotates such that the force applied to the workpiece is directed downward, against the work-holding platform. This wheel usually performs the grinding action by having a higher tangential speed than the workpiece at the point of contact. The other wheel, known as the regulating wheel (moving wheel in the diagram), is movable. This wheel is positioned to apply lateral pressure to the workpiece, and usually has either a very rough or rubber-bonded abrasive to trap the workpiece.\nThe speed of the two wheels relative to each other provides the grinding action and determines the rate at which material is removed from the workpiece. During operation the workpiece turns with the regulating wheel, with the same linear velocity at the point of contact and (ideally) no slipping. The grinding wheel turns faster, slipping past the surface of the workpiece at the point of contact and removing chips of material as it passes.\nTypes.\nThere are three forms of centerless grinding, differentiated primarily by the method used to feed the workpiece through the machine.\nThrough-feed.\nIn through-feed centerless grinding, the workpiece is fed through the grinding wheels completely, entering on one side and exiting on the opposite. The regulating wheel in through-feed grinding is canted away from the plane of the grinding wheel in such a way as to provide an axial force component, feeding the workpiece through between the two wheels. Through-feed grinding can be very efficient because it does not require a separate feed mechanism; however, it can only be used for parts with a simple cylindrical shape.\nEnd-feed.\nIn end-feed centerless grinding, the workpiece is fed axially into the machine on one side and comes to rest against an end stop; the grinding operation is performed, and then the workpiece is fed in the opposite direction to exit the machine. End-feed grinding is best for tapered workpieces.\nIn-feed.\nIn-feed centerless grinding is used to grind workpieces with relatively complex shapes, such as an hourglass shape. Before the process begins, the workpiece is loaded manually into the grinding machine and the regulating wheel is moved into place. The complexity of the part shapes and grinding wheel shapes required to grind them accurately prevent the workpiece from being fed axially through the machine.\nEquipment.\nCenterless grinding uses purpose-built centerless grinding machines. Such a machine will always include the grinding wheel, regulating wheel, and some means of supporting a workpiece. Modern machines may involve computer numerical control to allow automation and improve precision. Grinding wheels are interchangeable, to allow for different grits and shapes. Machines designed to accommodate through-feed grinding operations will allow the angle of the regulating wheel to be adjusted, to accommodate parts of different sizes.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "162289", "revid": "33594889", "url": "https://en.wikipedia.org/wiki?curid=162289", "title": "Computer-aided manufacturing", "text": "Computer-aided manufacturing (CAM) also known as computer-aided modeling or computer-aided machining is the use of software to control machine tools in the manufacturing of work pieces. This is not the only definition for CAM, but it is the most common. It may also refer to the use of a computer to assist in all operations of a manufacturing plant, including planning, management, transportation and storage. Its primary purpose is to create a faster production process and components and tooling with more precise dimensions and material consistency, which in some cases, uses only the required amount of raw material (thus minimizing waste), while simultaneously reducing energy consumption.\nCAM is now a system used in schools and lower educational purposes.\nCAM is a subsequent computer-aided process after computer-aided design (CAD) and sometimes computer-aided engineering (CAE), as the model generated in CAD and verified in CAE can be input into CAM software, which then controls the machine tool. CAM is used in many schools alongside computer-aided design (CAD) to create objects.\nOverview.\nTraditionally, CAM has been numerical control (NC) programming tool, wherein two-dimensional (2-D) or three-dimensional (3-D) models of components are generated in CAD. As with other \"computer-aided\" technologies, CAM does not eliminate the need for skilled professionals such as manufacturing engineers, NC programmers, or machinists. CAM leverages both the value of the most skilled manufacturing professionals through advanced productivity tools, while building the skills of new professionals through visualization, simulation and optimization tools.\nA CAM tool generally converts a model to a language the target machine in question understands, typically G-Code. The numerical control can be applied to machining tools, or more recently to 3D printers.\nHistory.\nEarly commercial applications of CAM were in large companies in the automotive and aerospace industries; for example, Pierre Béziers work developing the CAD/CAM application UNISURF in the 1960s for car body design and tooling at Renault. Alexander Hammer at DeLaval Steam Turbine Company invented a technique to progressively drill turbine blades out of a solid metal block of metal with the drill controlled by a punch card reader in 1950.\nHistorically, CAM software was seen to have several shortcomings that necessitated an overly high level of involvement by skilled CNC machinists. Fallows created the first CAD software but this had severe shortcomings and was promptly taken back into the developing stage. CAM software would output code for the least capable machine, as each machine tool control added on to the standard G-code set for increased flexibility. In some cases, such as improperly set up CAM software or specific tools, the CNC machine required manual editing before the program will run properly. None of these issues were so insurmountable that a thoughtful engineer or skilled machine operator could not overcome for prototyping or small production runs; G-Code is a simple language. In high production or high precision shops, a different set of problems were encountered where an experienced CNC machinist must both hand-code programs and run CAM software.\nThe integration of CAD with other components of CAD/CAM/CAE Product lifecycle management (PLM) environment requires an effective CAD data exchange. Usually it had been necessary to force the CAD operator to export the data in one of the common data formats, such as IGES or STL or Parasolid formats that are supported by a wide variety of software.\nThe output from the CAM software is usually a simple text file of G-code/M-codes, sometimes many thousands of commands long, that is then transferred to a machine tool using a direct numerical control (DNC) program or in modern Controllers using a common USB Storage Device.\nCAM packages could not, and still cannot, reason as a machinist can. They could not optimize toolpaths to the extent required of mass production. Users would select the type of tool, machining process and paths to be used. While an engineer may have a working knowledge of G-code programming, small optimization and wear issues compound over time. Mass-produced items that require machining are often initially created through casting or some other non-machine method. This enables hand-written, short, and highly optimized G-code that could not be produced in a CAM package.\nAt least in the United States, there is a shortage of young, skilled machinists entering the workforce able to perform at the extremes of manufacturing; high precision and mass production. As CAM software and machines become more complicated, the skills required of a machinist or machine operator advance to approach that of a computer programmer and engineer rather than eliminating the CNC machinist from the workforce.\nOvercoming historical shortcomings.\nOver time, the historical shortcomings of CAM are being attenuated, both by providers of niche solutions and by providers of high-end solutions. This is occurring primarily in three arenas:\nMachining process.\nMost machining progresses through many stages, each of which is implemented by a variety of basic and sophisticated strategies, depending on the part design, material, and software available.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "239076", "revid": "1157617720", "url": "https://en.wikipedia.org/wiki?curid=239076", "title": "Shielded metal arc welding", "text": "Shielded metal arc welding (SMAW), also known as manual metal arc welding (MMA or MMAW), flux shielded arc welding or informally as stick welding, is a manual arc welding process that uses a consumable electrode covered with a flux to lay the weld.\nAn electric current, in the form of either alternating current or direct current from a welding power supply, is used to form an electric arc between the electrode and the metals to be joined. The workpiece and the electrode melts forming a pool of molten metal (weld pool) that cools to form a joint. As the weld is laid, the flux coating of the electrode disintegrates, giving off vapors that serve as a shielding gas and providing a layer of slag, both of which protect the weld area from atmospheric contamination.\nBecause of the versatility of the process and the simplicity of its equipment and operation, shielded metal arc welding is one of the world's first and most popular welding processes. It dominates other welding processes in the maintenance and repair industry, and though flux-cored arc welding is growing in popularity, SMAW continues to be used extensively in the construction of heavy steel structures and in industrial fabrication. The process is used primarily to weld iron and steels (including stainless steel) but aluminium, nickel and copper alloys can also be welded with this method.\nDevelopment.\nAfter the discovery of the short pulsed electric arc in 1800 by Humphry Davy and of the continuous electric arc in 1802 by Vasily Petrov, there was little development in electrical welding until Auguste de Méritens developed a carbon arc torch that was patented in 1881.\nIn 1885, Nikolay Benardos and Stanisław Olszewski developed carbon arc welding, obtaining American patents from 1887 showing a rudimentary electrode holder. In 1888, the consumable metal electrode was invented by Nikolay Slavyanov. Later in 1890, C. L. Coffin received for his arc welding method that utilized a metal electrode. The process, like SMAW, deposited melted electrode metal into the weld as filler.\nAround 1900, Arthur Percy Strohmenger and Oscar Kjellberg released the first coated electrodes. Strohmenger used clay and lime coating to stabilize the arc, while Kjellberg dipped iron wire into mixtures of carbonates and silicates to coat the electrode. In 1912, Strohmenger released a heavily coated electrode, but high cost and complex production methods prevented these early electrodes from gaining popularity. In 1927, the development of an extrusion process reduced the cost of coating electrodes while allowing manufacturers to produce more complex coating mixtures designed for specific applications. In the 1950s, manufacturers introduced iron powder into the flux coating, making it possible to increase the welding speed.\nIn 1945 Karl Kristian Masden described an automated variation of SMAW, now known as gravity welding. It briefly gained popularity in the 1960s after receiving publicity for its use in Japanese shipyards though today its applications are limited. Another little used variation of the process, known as firecracker welding, was developed around the same time by George Hafergut in Austria. In 1964 laser welding was developed in Bell Laboratory with the intention of using this technology as a communication tool. Due to the large force of energy coupled with the small area of focus, this laser became a powerful heat source for cutting and tooling.\nOperation.\nTo strike the electric arc, the electrode is brought into contact with the workpiece by a very light touch of the electrode to the base metal. The electrode is then pulled back slightly. This initiates the arc and thus the melting of the workpiece and the consumable electrode, and causes droplets of the electrode to be passed from the electrode to the weld pool. Striking an arc, which varies widely based upon electrode and workpiece composition, can be the hardest skill for beginners. The orientation of the electrode to workpiece is where most stumble; if the electrode is held at a perpendicular angle to the workpiece, the tip will likely stick to the metal, which will fuse the electrode to the workpiece, causing it to heat up very rapidly. The tip of the electrode needs to be at a lower angle to the workpiece, which allows the weld pool to flow out of the arc. As the electrode melts, the flux covering disintegrates, giving off shielding gases that protect the weld area from oxygen and other atmospheric gases. In addition, the flux provides molten slag which covers the filler as it travels from electrode to the weld pool. Once part of the weld pool, the slag floats to the surface and protects the weld from contamination as it solidifies. Once hardened, it must be chipped away to reveal the finished weld. As welding progresses and the electrode melts, the welder must periodically stop welding to remove the remaining electrode stub and insert a new electrode into the electrode holder. This activity, combined with chipping away the slag, reduces the amount of time that the welder can spend laying the weld, making SMAW one of the least efficient welding processes. In general, the operator factor, or the percentage of operator's time spent laying weld, is approximately 25%.\nThe actual welding technique utilized depends on the electrode, the composition of the workpiece, and the position of the joint being welded. The choice of electrode and welding position also determine the welding speed. Flat welds require the least operator skill, and can be done with electrodes that melt quickly but solidify slowly. This permits higher welding speeds.\nSloped, vertical or upside-down welding requires more operator skill, and often necessitates the use of an electrode that solidifies quickly to prevent the molten metal from flowing out of the weld pool. However, this generally means that the electrode melts less quickly, thus increasing the time required to lay the weld.\nQuality.\nThe most common quality problems associated with SMAW include weld spatter, porosity, poor fusion, shallow penetration, and cracking.\nWeld spatter, while not affecting the integrity of the weld, damages its appearance and increases cleaning costs. Secondary finishing services are often required due to the aesthetic appearance caused by the occurrence of molten splatter. It can be caused by excessively high current, a long arc, or arc blow, a condition associated with direct current characterized by the electric arc being deflected away from the weld pool by magnetic forces. Arc blow can also cause porosity in the weld, as can joint contamination, high welding speed, and a long welding arc, especially when low-hydrogen electrodes are used.\nDefects to weld strength make welds prone to cracking. Porosity of the weld bead can cause serious weakening and is often detectable only via advanced nondestructive testing methods. Porosity occurs when the gases produced by the weld flux insufficiently shield the molten weld metal. An overexposed weld bead absorbs nitrogen, oxygen, and hydrogen from the atmosphere; these gases form tiny voids in the weld bead and are released while the weld cools. Poor fusion also affects the strength of the weld and is often easily visible. This is caused by low current, contaminated joint surfaces, or the use of an improper electrode. Shallow welds are weaker and can be mitigated by decreasing welding speed, increasing the current, or using a smaller electrode.\nOther factors in cracking propensity include high content of carbon, alloy, or sulfur in the base material, especially if low-hydrogen electrodes and preheating are not employed. Furthermore, workpieces should not be excessively constrained, as this introduces residual stresses into the workpieces (and specifically into the weld) as they expand and contract due to heating and cooling. As the weld cools and contracts, this residual stress can cause cracking in the weld.\nSafety.\nSMAW welding, like other welding methods, can be a dangerous and unhealthy practice if proper precautions are not taken. The process uses an open electric arc, which presents a risk of burns which are prevented by personal protective equipment in the form of heavy leather gloves and long sleeve jackets. Additionally, the brightness of the weld area can lead to a condition called arc eye or flash burn, in which ultraviolet light causes inflammation of the cornea and can burn the retinas of the eyes. Welding helmets with dark face plates are worn to prevent this exposure, and in recent years, new helmet models have been produced that feature a face plate that self-darkens upon exposure to high amounts of UV light. To protect bystanders, especially in industrial environments, translucent welding curtains often surround the welding area. These curtains, made of a polyvinyl chloride plastic film, shield nearby workers from exposure to the UV light from the electric arc, but should not be used to replace the filter glass used in helmets.\nIn addition, the vaporizing metal and flux materials expose welders to dangerous gases and particulate matter. The smoke produced contains particles of various types of oxides. The size of the particles in question tends to influence the toxicity of the fumes, with smaller particles presenting a greater danger. Additionally, gases like carbon dioxide and ozone can form, which can prove dangerous if ventilation is inadequate. Some of the latest welding masks are fitted with an electric powered fan to help disperse harmful fumes.\nApplication and materials.\nShielded metal arc welding is one of the world's most popular welding processes, accounting for over half of all welding in some countries. Because of its versatility and simplicity, it is particularly dominant in the maintenance and repair industry, and is heavily used in the construction of steel structures and in industrial fabrication. In recent years its use has declined as flux-cored arc welding has expanded in the construction industry and gas metal arc welding has become more popular in industrial environments. However, because of the low equipment cost and wide applicability, the process will likely remain popular, especially among amateurs and small businesses where specialized welding processes are uneconomical and unnecessary.\nSMAW is often used to weld carbon steel, low and high alloy steel, stainless steel, cast iron, and ductile iron. While less popular for non-ferrous materials, it can be used on nickel and copper and their alloys and, in rare cases, on aluminium. The thickness of the material being welded is bounded on the low end primarily by the skill of the welder, but rarely does it drop below . No upper bound exists: with proper joint preparation and use of multiple passes, materials of virtually unlimited thicknesses can be joined. Furthermore, depending on the electrode used and the skill of the welder, SMAW can be used in any position.\nEquipment.\nShielded metal arc welding equipment typically consists of a constant current welding power supply and an electrode, with an electrode holder, a ground clamp, and welding cables (also known as welding leads) connecting the two. \nPower supply.\nThe power supply used in SMAW has constant current output, ensuring that the current (and thus the heat) remains relatively constant, even if the arc distance and voltage change. This is important because most applications of SMAW are manual, requiring that an operator hold the torch. Maintaining a suitably steady arc distance is difficult if a constant voltage power source is used instead, since it can cause dramatic heat variations and make welding more difficult. However, because the current is not maintained absolutely constant, skilled welders performing complicated welds can vary the arc length to cause minor fluctuations in the current.\nThe preferred polarity of the SMAW system depends primarily upon the electrode being used and the desired properties of the weld. Direct current with a negatively charged electrode (DCEN) causes heat to build up in the parent material, increasing the electrode melting rate and decreasing the depth of the weld. Reversing the polarity so that the electrode is positively charged (DCEP) and the workpiece is negatively charged increases the weld penetration. With alternating current the polarity changes over 100 times per second, creating an even heat distribution and providing a balance between electrode melting rate and penetration.\nTypically, the equipment used for SMAW consists of a step-down transformer and for direct current models a rectifier, which converts alternating current into direct current. Because the power normally supplied to the welding machine is high-voltage alternating current, the welding transformer is used to reduce the voltage and increase the current. As a result, instead of 220 V at 50 A, for example, the power supplied by the transformer is around 17–45 V at currents up to 600 A. A number of different types of transformers can be used to produce this effect, including multiple coil and inverter machines, with each using a different method to manipulate the welding current. The multiple coil type adjusts the current by either varying the number of turns in the coil (in tap-type transformers) or by varying the distance between the primary and secondary coils (in movable coil or movable core transformers). Inverters, which are smaller and thus more portable, use electronic components to change the current characteristics.\nElectrical generators and alternators are frequently used as portable welding power supplies, but because of lower efficiency and greater costs, they are less frequently used in industry. Maintenance also tends to be more difficult, because of the complexities of using a combustion engine as a power source. However, in one sense they are simpler: the use of a separate rectifier is unnecessary because they can provide either AC or DC. However, the engine driven units are most practical in field work where the welding often must be done out of doors and in locations where transformer type welders are not usable because there is no power source available to be transformed.\nIn some units the alternator is essentially the same as that used in portable generating sets used to supply mains power, modified to produce a higher current at a lower voltage but still at the 50 or 60 Hz grid frequency. In higher-quality units an alternator with more poles is used and supplies current at a higher frequency, such as 400 Hz. The smaller amount of time the high-frequency waveform spends near zero makes it much easier to strike and maintain a stable arc than with the cheaper grid-frequency sets or grid-frequency mains-powered units.\nElectrode.\nThe choice of electrode for SMAW depends on a number of factors, including the weld material, welding position and the desired weld properties. The electrode is coated in a metal mixture called flux, which gives off gases as it decomposes to prevent weld contamination, introduces deoxidizers to purify the weld, causes weld-protecting slag to form, improves the arc stability, and provides alloying elements to improve the weld quality. Electrodes can be divided into three groups—those designed to melt quickly are called \"fast-fill\" electrodes, those designed to solidify quickly are called \"fast-freeze\" electrodes, and intermediate electrodes go by the name \"fill-freeze\" or \"fast-follow\" electrodes. Fast-fill electrodes are designed to melt quickly so that the welding speed can be maximized, while fast-freeze electrodes supply filler metal that solidifies quickly, making welding in a variety of positions possible by preventing the weld pool from shifting significantly before solidifying.\nThe composition of the electrode core is generally similar and sometimes identical to that of the base material. But even though a number of feasible options exist, a slight difference in alloy composition can strongly impact the properties of the resulting weld. This is especially true of alloy steels such as HSLA steels. Likewise, electrodes of compositions similar to those of the base materials are often used for welding nonferrous materials like aluminium and copper. However, sometimes it is desirable to use electrodes with core materials significantly different from the base material. For example, stainless steel electrodes are sometimes used to weld two pieces of carbon steel, and are often utilized to weld stainless steel workpieces with carbon steel workpieces.\nElectrode coatings can consist of a number of different compounds, including rutile, calcium fluoride, cellulose, and iron powder. Rutile electrodes, coated with 25%–45% TiO2, are characterized by ease of use and good appearance of the resulting weld. However, they create welds with high hydrogen content, encouraging embrittlement and cracking. Electrodes containing calcium fluoride (CaF2), sometimes known as basic or low-hydrogen electrodes, are hygroscopic and must be stored in dry conditions. They produce strong welds, but with a coarse and convex-shaped joint surface. Electrodes coated with cellulose, especially when combined with rutile, provide deep weld penetration, but because of their high moisture content, special procedures must be used to prevent excessive risk of cracking. Finally, iron powder is a common coating additive that increases the rate at which the electrode fills the weld joint, up to twice as fast.\nTo identify different electrodes, the American Welding Society established a system that assigns electrodes with a four- or five-digit number. Covered electrodes made of mild or low alloy steel carry the prefix \"E\", followed by their number. The first two or three digits of the number specify the tensile strength of the weld metal, in thousand pounds per square inch (ksi). The penultimate digit generally identifies the welding positions permissible with the electrode, typically using the values 1 (normally fast-freeze electrodes, implying all position welding) and 2 (normally fast-fill electrodes, implying horizontal welding only). The welding current and type of electrode covering are specified by the last two digits together. When applicable, a suffix is used to denote the alloying element being contributed by the electrode.\nCommon electrodes include the E6010, a fast-freeze, all-position electrode with a minimum tensile strength of which is operated using DCEP, and provides deep weld penetration with a forceful arc capable of burning through light rust or oxides on the workpiece. E6011 is similar except its flux coating allows it to be used with alternating current in addition to DCEP. E7024 is a fast-fill electrode, used primarily to make flat or horizontal fillet welds using AC, DCEN, or DCEP. Examples of fill-freeze electrodes are the E6012, E6013, and E7014, all of which provide a compromise between fast welding speeds and all-position welding.\nProcess variations.\nThough SMAW is almost exclusively a manual arc welding process, one notable process variation exists, known as gravity welding or gravity arc welding. It serves as an automated version of the traditional shielded metal arc welding process, employing an electrode holder attached to an inclined bar along the length of the weld. Once started, the process continues until the electrode is spent, allowing the operator to manage multiple gravity welding systems. The electrodes employed (often E6027 or E7024) are coated heavily in flux, and are typically in length and about thick. As in manual SMAW, a constant current welding power supply is used, with either negative polarity direct current or alternating current. Due to a rise in the use of semiautomatic welding processes such as flux-cored arc welding, the popularity of gravity welding has fallen as its economic advantage over such methods is often minimal. Other SMAW-related methods that are even less frequently used include firecracker welding, an automatic method for making butt and fillet welds, and massive electrode welding, a process for welding large components or structures that can deposit up to of weld metal per hour.", "Engineering,_Manufacturing": 0.9998885393, "qwen": "Yes"}
{"id": "240452", "revid": "46289122", "url": "https://en.wikipedia.org/wiki?curid=240452", "title": "Product life-cycle management (marketing)", "text": "Product life-cycle management (PLM) is the succession of strategies by business management as a product goes through its life-cycle. The conditions in which a product is sold (advertising, saturation) changes over time and must be managed as it moves through its succession of stages.\nGoals.\nThe goals of product life cycle management (PLM) are to reduce time to market, improve product quality, reduce prototyping costs, identify potential sales opportunities and revenue contributions, maintain and sustain operational serviceability, and reduce environmental impacts at end-of-life. To create successful new products the company must understand its customers, markets and competitors. Product Lifecycle Management (PLM) integrates people, data, processes and business systems. It provides product information for companies and their extended supply chain enterprise. PLM solutions help organizations overcome the increased complexity and engineering challenges of developing new products for the global competitive markets.\nProduct life cycle.\nThe concept of product life cycle (PLC) concerns the life of a product in the market with respect to business/commercial costs and sales measures. The product life cycle proceeds through multiple phases, involves many professional disciplines, and requires many skills, tools and processes. PLC management makes the following three assumptions:\nOnce the product is designed and put into the market, the offering should be managed efficiently for the buyers to get value from it. Before entering into any market complete analysis is carried out by the industry for both external and internal factors including the laws and regulations, environment, economics, cultural values and market needs. From the business perspective, as a good business, the product needs to be sold before it finishes its life. In terms of profitability, expiry may jolt the overall profitability of the business therefore there are few strategies, which are practiced to ensure that the product is sold within the defined period of maturity.\nExtending the product life cycle.\nExtending the product life cycle by improving sales, can be done through\nSomething important to notice is that all these techniques rely on advertising to become known. Advertising needs the others to target other potential customers and not the same over and over again.\nCharacteristics of PLC stages.\nThere are the following major product life cycle stages:\nIdentifying PLC stages.\nIdentifying the stage of a product is an art more than a science, but it's possible to find patterns in some of the general product features at each stage. Identifying product stages when the product is in transition is very difficult. More recently, it has been shown that user-generated contents (UGC) (e.g., in the form of online product reviews) has the potential to reveal buyer personality characteristics that can in turn be used to identify product life cycle stage.", "Engineering,_Manufacturing": 0.9985882044, "qwen": "Yes"}
{"id": "21544094", "revid": "23683751", "url": "https://en.wikipedia.org/wiki?curid=21544094", "title": "Flow-shop scheduling", "text": "Flow-shop scheduling is an optimization problem in computer science and operations research. It is a variant of optimal job scheduling. In a general job-scheduling problem, we are given \"n\" jobs \"J\"1, \"J\"2, ..., \"Jn\" of varying processing times, which need to be scheduled on \"m\" machines with varying processing power, while trying to minimize the makespan – the total length of the schedule (that is, when all the jobs have finished processing). In the specific variant known as \"flow-shop scheduling\", each job contains exactly \"m\" operations. The \"i\"-th operation of the job must be executed on the \"i\"-th machine. No machine can perform more than one operation simultaneously. For each operation of each job, execution time is specified.\nFlow-shop scheduling is a special case of job-shop scheduling where there is strict order of all operations to be performed on all jobs. Flow-shop scheduling may apply as well to production facilities as to computing designs. A special type of flow-shop scheduling problem is the permutation flow-shop scheduling problem in which the processing order of the jobs on the resources is the same for each subsequent step of processing.\nIn the standard three-field notation for optimal-job-scheduling problems, the flow-shop variant is denoted by F in the first field. For example, the problem denoted by \" F3|formula_1|formula_2\" is a 3-machines flow-shop problem with unit processing times, where the goal is to minimize the maximum completion time.\nFormal definition.\nThere are \"m\" machines and \"n\" jobs. Each job contains exactly \"m\" operations. The \"i\"-th operation of the job must be executed on the \"i\"-th machine. No machine can perform more than one operation simultaneously. For each operation of each job, execution time is specified.\nOperations within one job must be performed in the specified order. The first operation gets executed on the first machine, then (as the first operation is finished) the second operation on the second machine, and so on until the \"m\"-th operation. Jobs can be executed in any order, however. Problem definition implies that this job order is exactly the same for each machine. The problem is to determine the optimal such arrangement, i.e. the one with the shortest possible total job execution makespan.\nSequencing performance measurements (γ).\nThe sequencing problem can be stated as determining a sequence S such that one or several sequencing objectives are optimized. \ndetailed discussion of performance measurement can be found in Malakooti(2013).\nComplexity of flow-shop scheduling.\nAs presented by Garey et al. (1976), most of extensions of the flow-shop-scheduling problems are NP-hard and few of them can be solved optimally in O(nlogn); for example, F2|prmu|Cmax can be solved optimally by using Johnson's Rule.\nTaillard provides substantial benchmark problems for scheduling flow shops, open shops, and job shops.\nSolution methods.\nThe proposed methods to solve flow-shop-scheduling problems can be classified as exact algorithm such as branch and bound and heuristic algorithm such as genetic algorithm.\nMinimizing makespan, Cmax.\nF2|prmu|Cmax and F3|prmu|Cmax can be solved optimally by using Johnson's Rule but for general case there is no algorithm that guarantee the optimality of the solution.\nThe flow shop contains n jobs simultaneously available at time zero and to be processed by two machines arranged in series with unlimited storage in between them. The processing time of all jobs are known with certainty. It is required to schedule n jobs on machines so as to minimize makespan. The Johnson's rule for scheduling jobs in two-machine flow shop is given below.\nIn an optimal schedule, job i precedes job j if \"min{p1i,p2j} < min{p1j,p2i}\". Where as, p1i is the processing time of job i on machine 1 and p2i is the processing time of job i on machine 2. Similarly, p1j and p2j are processing times of job j on machine 1 and machine 2 respectively.\nFor Johnson's algorithm:\nJohnson's algorithm:\nThis type schedule is referred as SPT(1)–LPT(2) schedule.\nA detailed discussion of the available solution methods are provided by Malakooti (2013).", "Engineering,_Manufacturing": 0.99945575, "qwen": "Yes"}
{"id": "21548779", "revid": "4904587", "url": "https://en.wikipedia.org/wiki?curid=21548779", "title": "Foundry Products Operations", "text": "Foundry Products Operations was a subsidiary operation of the Cincinnati Milling Machine Company (CMM), a company which no longer exists. Some parts of the company evolved into the present Milacron, Inc. and Cincinnati Machine. CMM relied heavily on castings for the manufacturing of its machine tool products. The castings were produced at Cincinnati foundries owned by CMM (and later, Milacron, Inc.) and at foundries independent of CMM, between 1907 and 1988.\nHistory.\nBeginnings of CMM reliance on castings.\nIn 1884 the Cincinnati Screw and Tap Company was incorporated. The company was in the business of making screws and taps, but also began to make machine tools. A basic component in machine tools at this time was gray iron castings. The company bought castings from jobbing foundries for the machine tools it manufactured. Some of the Cincinnati local foundries which supplied to the machine tool company included the Blackburn Foundry, Buckeye Foundry Company, the Steel Foundry Company (Cincinnati) and others.\nIn 1889 the screw and tap business was sold off, as the company focused on machine tool business. It was renamed as the Cincinnati Milling Machine Co. (CMM). CMM continued to operate in the central business district of Cincinnati and purchased castings from a number of local foundries.\nIn 1905 the company was sold in total to Frederick A. Geier, who became president. Geier had been a partner in the concern previously. Until this time the company had had some problems with the locations in the business district: at least one flood and a fire had caused it to relocate.\nRelocation to Oakley.\nIn October 1906 CMM announced plans for a new vertically integrated factory to be built in Oakley, a suburb of Cincinnati. A site was purchased which was named the Factory Colony. This site was developed to include a two-story administration building 62 × , a foundry building 62 × , a building for cleaning castings and storing 62 × , a charging building 62 × , and a pattern shop 62 × . These buildings would be all of brick and steel construction. A few months later the company announced the foundry would be 350 × , with the pattern shop to be 50 × . A power house would also be erected with a size of 75 × 100 feet. The foundry was planned to provide castings to all companies which would locate to the new industrial park.\nGeier reasoned a captive foundry operation was needed because \"the uncertain supply of castings had been a great handicap to production at a time when demand was far greater than our ability to supply\".\nA few months after making the construction announcement, CMM announced they were leasing a foundry on Patternson Street in Cincinnati, to be occupied be the Modern Foundry until the construction was completed in Oakley. The Modern Foundry was the beginnings of what became the Foundry Products Operations of the Cincinnati Milling Machine Company.\nThe foundry was erected by the Interstate Engineering Company, opening in 1907. It was the first production facility in the new industrial park, as a separate organization called the Modern Foundry and was located at the corner of Marburg and Disney Street in Oakley. The new foundry was fully operational by 1908 and could melt 30 tons per day in its cupola furnaces.\nThe foundry also organized with other foundries in Cincinnati: Lunkenheimer, Buckeye Foundry Company and the John B. Morris Foundry, to form the Associated Foundries of Cincinnati, supplying castings to Cincinnati industry. The first manager of the Modern Foundry was Walter H. Geier.\nBy the mid-1930s the Factory Colony was considered one of the world's largest manufacturers of machine tools and employed thousands of workers.\nChosen to represent the foundry industry in a mural.\nWinold Reiss was contracted to produce murals depicting workers in Cincinnati industries, for the new Cincinnati Union Terminal. To depict the foundry industry, he visited the Modern Foundry to get ideas and set a scene for one of the murals, called \"Foundry and Machine Shop Products\". In this mural, a man (modeled by Joseph Schwope, 1898–1980) is skimming a ladle of iron, while an iron pourer (modeled by Bill Rengering, 1901–1985) pours a mold. A metallurgist (modeled by Emil Weston, 1900–1990) measures the metal temperature using an optical pyrometer. In the background a cupola tender (Bill Ennix, 1886–1944) watches over the work. One source credits the model for the cupola tender as being Howard Fredericks.\nA copy of the original photograph is shown in the book \"They Built a City: 150 Years of Industrial Cincinnati\".\nAfter visiting the Modern Foundry for a couple days, and after everything was arranged as Reiss wanted to capture the depiction of the foundry industry, the photograph was taken during the pouring of a mold. Reiss made a sketch of the elements he wanted to include from the photograph, simplifying certain elements for his mural. He submitted this sketch to the Ravenna Mosaic Company of Italy for production into the tesserae medium of the mosaic. The glass tesserae pieces were attached to paper and shipped to Cincinnati Union Terminal. The paper-backed pieces were pressed into the plaster on the terminal wall. Interstitial places were filled with colored mortar. In 1973, when the terminal concourse was to be torn down, this mural and 13 others by Reiss were carefully removed and transported for display at Cincinnati/Northern Kentucky International Airport.\nPreparations for a new expansion, gearing up for war.\nIn the early 1930s Frederick V. Geier (son of Frederick A. Geier) was sent to Germany to explore the possibility of establishing an operation there for manufacturing machine tools. He was shocked by the scale of industrial development and concluded a war in Europe was imminent. He believed that the United States needed to make changes to support its needs and those of its allies. \nThe foundry operation was licensed to produce iron under the Meehanite process in 1935 for the cupola operation. In 1937 the Blackburn Foundry was taken over to support production of large castings. In 1938, based on his studies of what was happening in Europe and despite a deep recession, Geier launched a program to double the plant size, including construction of a new foundry.\nNew Foundry.\nThe New Foundry opened and poured its first heat by December 1940, about a year before the Attack on Pearl Harbor. With the opening of the New Foundry, the company tore down the old Modern Foundry. At this site, it developed additional machining and assembly space, which enabled a seven-fold increase in production during World War II. The Modern Foundry poured its last heat in 1941.\nThe Metal Fabricating Division foundry, as it came to be called, supplied all the needs of the Cincinnati Milling Machine Company and its successor, Milacron, Inc. At least three buildings were constructed, totaling more than .\n By 1942 the Cincinnati Milling Machine Company Foundry (CMM Co. Foundry) was producing 35,000 tons of castings, with an additional 32,000 tons being purchased from other sources. Melting in the New Foundry was done by up to four cupola furnaces. Production in the foundry was around the clock, seven days a week. Additional castings were needed, and the 'Mill' turned to outside Cincinnati local foundries. At total of 27 outside foundries were also supplying castings to the Mill.\nArmy-Navy \"E\" Award.\nCincinnati Milling Machine received the prestigious Army-Navy \"E\" Award on March 6, 1942, in part through the efforts of the New Foundry and the other local foundries in supplying thousands of castings, which were used to produce 17,511 machine tools in 1942 alone to gear up for war. Late in the World War II era, they dropped production considerably, to less than half of that amount, to about 15,000 tons per year.\nPost war.\nAt the end of the war and into the 1950s, production stabilized at about 12,000 tons per year, with purchased castings at about 3,000 tons per year. The CMM Co. Foundry also produced castings for direct sales to other customers, but at a low rate of about 1,000 tons per year. Because the foundry was wholly owned by CMM, other machine tool makers were reluctant to have their competitor making castings for them. In the late postwar period, Cincinnati local foundries had an excess production capacity.\nThe production of castings was similar to the way they were made since the early days of founding. Molding was done with green sand until sometime in the 1960s or 1970s, when the furan molding process was adopted for medium and large sized castings. Melting continued using the cupola. Most requirements on the foundry were for gray iron, the material normally used in machine tool castings. With the discovery of ductile iron, the foundry began producing ductile in the 1950s, using open ladle treatments or the Gazal porous plug process. Not many machine tool parts were needed in ductile iron.\nCastings for overseas production facilities.\nIn 1964 Milacron constructed an entirely new foundry in England to supply castings for its European machine tool business. This foundry was known as Cincinnati Milacron Ltd, Foundry Operations, Tamworth, England. In the 1970s and 1980s the company was the largest single employer in Biggleswade, Bedfordshire, England.\nChange in the 1970s.\nIn the 1970s, great changes came to the machine tool industry, especially in Cincinnati. Milacron diversified its interests by developing machines that made plastic products . A large part of its success in making machinery was in the use of ductile iron in the plastic injection machinery.\nSale to Cast-Fab Technologies.\nIn 1988, Cincinnati Milacron, Inc. restructured and reorganized the company. It sold the Met-Fab Division facility, including the Oakley foundry. In the previous ten-year period, Milacron had invested more than $8 million in the plant. \nThe sale represented the end of the Foundry Products Operations. The modernized New Foundry was adapted as a metalcasting operation that supplies many companies and customers with a full range of gray and ductile iron castings. Named Cast-Fab Technologies, Inc., this foundry ceased operation in November 2016, transferring remaining business to Elyria Cast-Fab.\nAs of the end of 2012, the entire 100-acre site that once held the Cincinnati Milling Machine Company was cleared to bare ground.", "Engineering,_Manufacturing": 0.9998548031, "qwen": "Yes"}
{"id": "22730555", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=22730555", "title": "Pou Chen Corporation", "text": "Pou Chen Corporation  (Taiwan Stock Exchange Stock Code: 9904), or Pou Chen, is a leading footwear manufacturer in Taiwan, and the largest branded athletic and casual footwear manufacturer in the world. It is headquartered in Taichung City, Taiwan.\nThe Group was founded in Fuxing, Changhwa in 1969 by Tsai's family. It focuses on the manufacturing of athletic and casual footwear on an OEM/ODM basis for major global brands such as Nike, Adidas, Asics, Clarks, Reebok, Puma, New Balance, Crocs, Merrell, Timberland, Converse and Salomon. It owns production lines in China, Indonesia, Mexico and Vietnam. Its subsidiary, Yue Yuen Industrial Holdings , is the world's largest athletic shoe manufacturer which focuses on footwear material manufacturing.\nIn April 2014, 40,000 workers were protesting Yue Yuen Industrial Holding failure to pay the full social security and house renting contribution. The protests were triggered by a staff member who worked for 18 years at Yue Yuen who did not get her full pension. The company did not pay 250 yuan per month to the employee that they should have.\nBesides footwear business, Pou Chen used to engage in electronics business by investing Global Brands Manufacture Limited (GBM), which is engaged in manufacturing printed circuit boards and assembling. However, the erupted global financial crisis in 2008 caused the group to readjust its business strategy and to dispose its 40% stake in GBM by auction in March 2010.", "Engineering,_Manufacturing": 0.9333123565, "qwen": "Yes"}
{"id": "1029949", "revid": "6727347", "url": "https://en.wikipedia.org/wiki?curid=1029949", "title": "Printed circuit board milling", "text": "Printed circuit board milling (also: isolation milling) is the milling process used for removing areas of copper from a sheet of printed circuit board (PCB) material to recreate the pads, signal traces and structures according to patterns from a digital circuit board plan known as a \"layout file\". Similar to the more common and well known chemical PCB etch process, the PCB milling process is subtractive: material is removed to create the electrical isolation and ground planes required. However, unlike the chemical etch process, PCB milling is typically a non-chemical process and as such it can be completed in a typical office or lab environment without exposure to hazardous chemicals. High quality circuit boards can be produced using either process. In the case of PCB milling, the quality of a circuit board is chiefly determined by the system's true, or weighted, milling accuracy and control as well as the condition (sharpness, temper) of the milling bits and their respective feed/rotational speeds. By contrast, in the chemical etch process, the quality of a circuit board depends on the accuracy and/or quality of the mask used to protect the copper from the chemicals and the state of the etching chemicals.\nAdvantages.\nPCB milling has advantages for both prototyping and some special PCB designs. The biggest benefit is that one does not have to use chemicals to produce PCBs.\nWhen creating a prototype, outsourcing a board takes time. An alternative is to make a PCB in-house. Using the wet process, in-house production presents problems with chemicals and disposing thereof. High-resolution boards using the wet process are hard to achieve and still, when done, one still has to drill and eventually cut out the PCB from the base material.\nCNC machine prototyping can provide a fast-turnaround board production process without the need for wet processing. If a CNC machine is already used for drilling, this single machine could carry out both parts of the process, drilling and milling. A CNC machine is used to process drilling, milling and cutting.\nMany boards that are simple for milling would be very difficult to process by wet etching and manual drilling afterward in a laboratory environment without using top-of-the-line systems that usually cost many times more than CNC milling machines.\nIn mass production, milling is unlikely to replace etching although the use of CNC is already standard practice for drilling the boards.\nHardware.\nA PCB milling system is a single machine that can perform all of the required actions to create a prototype board, with the exception of inserting \"vias\" and \"through hole plating\". Most of these machines require only a standard AC mains outlet and a shop-type vacuum cleaner for operation.\nSoftware.\nSoftware for milling PCBs is usually delivered by the CNC machine manufacturer. Most of the packages can be split in two main categories – raster and vector.\nSoftware that produces tool paths using raster calculation method tends to have lower resolution of processing than the vector based software since it relies on the raster information it receives.\nMechanical system.\nThe mechanics behind a PCB milling machine are fairly straightforward and have their roots in CNC milling technology. A PCB milling system is similar to a miniature and highly accurate NC milling table. For machine control, positioning information and machine control commands are sent from the controlling software via a serial port or parallel port connection to the milling machine's on-board controller. The controller is then responsible for driving and monitoring the various positioning components which move the milling head and gantry and control the spindle speed. Spindle speeds can range from 30,000 RPM to 100,000 RPM depending on the milling system, with higher spindle speeds equating to better accuracy, in a nutshell the smaller the tool diameter the higher RPM you need. Typically this drive system comprises non-monitored stepper motors for the X/Y axis, an on-off non-monitored solenoid, pneumatic piston or lead screw for the Z-axis, and a DC motor control circuit for spindle speed, none of which provide positional feedback. More advanced systems provide a monitored stepper motor Z-axis drive for greater control during milling and drilling as well as more advanced RF spindle motor control circuits that provide better control over a wider range of speeds.\nX and Y-axis control.\nFor the X and Y-axis drive systems most PCB milling machines use stepper motors that drive a precision lead screw. The lead screw is in turn linked to the gantry or milling head by a special precision machined connection assembly. To maintain correct alignment during milling, the gantry or milling head's direction of travel is guided along using linear or dovetailed bearing(s). Most X/Y drive systems provide user control, via software, of the milling speed, which determines how fast the stepper motors drive their respective axes.\nZ-axis control.\nZ-axis drive and control are handled in several ways. The first and most common is a simple solenoid that pushes against a spring. When the solenoid is energized it pushes the milling head down against a spring stop that limits the downward travel. The rate of descent as well as the amount of force exerted on the spring stop must be manually set by mechanically adjusting the position of the solenoid's plunger. The second type of Z-axis control is through the use of a pneumatic cylinder and a software-driven gate valve. Due to the small cylinder size and the amount of air pressure used to drive it there is little range of control between the up and down stops. Both the solenoid and pneumatic system cannot position the head anywhere other than the endpoints, and are therefore useful for only simple 'up/down' milling tasks. The final type of Z-axis control uses a stepper motor that allows the milling head to be moved in small accurate steps up or down. Further, the speed of these steps can be adjusted to allow tool bits to be eased into the board material rather than hammered into it. The depth (number of steps required) as well as the downward/upward speed is under user control via the controlling software.\nOne of the major challenges with milling PCBs is handling variations in flatness. Since conventional etching techniques rely on optical masks that sit right on the copper layer they can conform to any slight bends in the material so all features are replicated faithfully.\nWhen milling PCBs however, any minute height variations encountered when milling will cause conical bits to either sink deeper (creating a wider cut) or rise off the surface, leaving an uncut section. Before cutting some systems perform height mapping probes across the board to measure height variations and adjust the Z values in the G-code beforehand.\nTooling.\nPCBs may be machined with conventional endmills, conical d-bit cutters, and spade mills. D-bits and spade mills are cheap and as they have a small point allow the traces to be close together. Taylor's equation, Vc Tn = C, can predict tool life for a given surface speed.\nAlternatives.\nA method with similar advantages to mechanical milling is laser etching and laser drilling. Etching PCBs with lasers offers the same advantages as mechanical milling in regards to quick turnaround times, but the nature of the laser etching process is preferable to both milling and chemical etching when it comes to physical variations exerted on the object. Whereas mechanical milling and chemical etching exact physical stress on the board, laser etching offers non-contact surface removal, making it a superior option for PCBs where precision and geometric accuracy are at a premium, such as RF and microwave designs. Laser drilling is more precise, has extremely low power consumption compared with other techniques, requires less maintenance, does not use lubricants or drill bits, low rates of wear, does not use abrasive materials, does not ruin the boards, is more eco friendly, and in the most high-powered machines, the drilling is instant, but is expensive. An additional emerging alternative to milling and laser etching is an additive approach based upon printing the conductive trace. Such PCB printers come at a range of price points and with differing features but also offer rapid in-house circuit manufacture, with very little to no waste. An example of such a technology that produces simpler, low layer count PCBs is Voltera. A system at the higher layer-count end of the additive manufacturing approach is Nano Dimension's DragonFly technology which prints complex high layer count circuits as well as electro-mechanical parts.", "Engineering,_Manufacturing": 1.0000076294, "qwen": "Yes"}
{"id": "30855994", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=30855994", "title": "Macor", "text": "Macor is the trademark for a machinable glass-ceramic developed and sold by Corning Inc. It is a white material that looks somewhat like porcelain. Macor is a good thermal insulator and is stable up to temperatures of 1000 °C, with very little thermal expansion or outgassing. It can be machined using standard metalworking tools.\nComposition.\nMacor is made up of fluorphlogopite mica in a borosilicate glass matrix. Its composition is roughly: 46% silica (SiO2), 17% magnesium oxide (MgO), 16% aluminium oxide (Al2O3), 10% potassium oxide (K2O), 7% boron trioxide (B2O3), 4% fluorine (F).\nProperties.\nMacor has a density of 2.52 g/cm3, a Young's modulus of 66.9 GPa at 25 °C, a specific stiffness of 26.55 m2s−2, a Poisson’s Ratio of 0.29 and a thermal conductivity of 1.46 W/(m·K). It has a low-temperature (25 to 300 °C) thermal expansion of 9.3 K−1. Its compressive strength is 50 lb/in2 (~350 MPa). Nominal engineering properties are comparable to borosilicate glass.\nExtremely machinable, Macor offers tight-tolerance capabilities, allowing complicated shape design (optimal performances up to\n±0.013 mm for dimensions, < 0.5 μm for finished surface and up to 0.013 μm for polished surface). Macor remains continuously stable at 800 °C, with a maximum peak at 1000 °C under no load, and unlike ductile materials, doesn’t creep or deform.\nIts coefficient of thermal expansion readily matches most metals and sealing glasses. As an electric insulator, particularly at high temperatures, it is excellent at high voltages and a broad spectrum of frequencies.\nMacor comes in a standard size maxi slab (about ). Components, bars, rods and plates can be machined within the size of this slab (hand tools can be used).\nApplications.\nMacor is used in the following applications:\nSafety.\nThere are no major safety concerns or toxic effects associated with Macor. The dust created when machining it can be an irritant, and inhalation should be avoided.\nMachining guidelines.\nKey factors for successful machining are proper machining speeds and coolant. Macor can be machined with high-speed steel tools, but carbide tools are recommended for longer wear. Best results achieved by using a water-soluble coolant (such as Cimstar 40 – Pink) especially formulated for cutting and grinding glass or ceramics. Note: No post-firing is required after machining.", "Engineering,_Manufacturing": 0.99999547, "qwen": "Yes"}
{"id": "19056964", "revid": "6727347", "url": "https://en.wikipedia.org/wiki?curid=19056964", "title": "Run-out", "text": "Run-out or runout is an inaccuracy of rotating mechanical systems, specifically that the tool or shaft does not rotate exactly in line with the main axis. For example; when drilling, run-out will result in a larger hole than the drill's nominal diameter due to the drill \nbeing rotated eccentrically (off axis instead of in line). In the case of bearings, run-out will cause vibration of the machine and increased loads on the bearings.\nRun-out is dynamic and cannot be compensated. If a rotating component, such as a drill chuck, does not hold the drill centrally, then as it rotates the rotating drill will turn about a secondary axis.\nRun-out has two main forms:\nIn addition, irregular run-out is the result of worn or rough bearings which can manifest itself as either axial or radial run-out.\nRunout will be present in any rotating system and, depending on the system, the different forms may either combine increasing total runout, or cancel reducing total runout. At any point along a tool or shaft it is not possible to determine whether runout is axial or radial; only by measuring along the axis can they be differentiated.\nAbsolute alignment is impossible; a degree of error will always be present.\nRadial run-out.\nRadial run-out is the result of a rotating component running off centre, such as a ball bearing with an offset centre. This means that the rotating tool or shaft, instead of being centrally aligned, will rotate about a secondary axis. In general, cutting tools are more tolerant of radial run-out since the edges are parallel to the line of cutting tending to keep the tool tip aligned. However, a rotating shaft may be less tolerant of radial run-out since the centre of gravity is displaced by the amount of run-out.\nAxial run-out.\nAxial run-out is the result of a rotating component not being parallel with the axis, such as a drill chuck not holding the drill exactly in line with the axis. In general, cutting tools are less tolerant of axial run-out since the tool tip tends to dig in and further increase run-out. However, a shaft may be more tolerant of axial run-out since the centre of gravity is displaced less.\nMeasurement.\nTypically run-out is measured using a dial indicator pressed against the rotating component while it is turned. Total indicated run-out (TIR) is a technician's term for the measured run-out of any rotating system, including all forms of run-out, at the measured point.", "Engineering,_Manufacturing": 0.9999780655, "qwen": "Yes"}
{"id": "18421531", "revid": "45632440", "url": "https://en.wikipedia.org/wiki?curid=18421531", "title": "Precision engineering", "text": "Precision engineering is a subdiscipline of electrical engineering, software engineering, electronics engineering, mechanical engineering, and optical engineering concerned with designing machines, fixtures, and other structures that have exceptionally low tolerances, are repeatable, and are stable over time. These approaches have applications in machine tools, MEMS, NEMS, optoelectronics design, and many other fields.\nPrecision engineering is a branch of engineering that focus on the design, development and manufacture of product with high levels of accuracy and repeatability.\nit involves the use of advanced technologies and techniques to achieve tight tolerance and dimensional control is the manufacturing process.\nOverview.\nProfessors Hiromu Nakazawa and Pat McKeown provide the following list of goals for precision engineering:", "Engineering,_Manufacturing": 0.9999872446, "qwen": "Yes"}
{"id": "7959617", "revid": "283288", "url": "https://en.wikipedia.org/wiki?curid=7959617", "title": "Saleen Special Vehicles", "text": "Saleen Special Vehicles or SSV, was a Saleen-owned and Saleen-operated small-volume, specialty vehicle assembly plant located at 1225 East Maple Road in Troy, Michigan. The building housing this facility was previously a Stanley door-manufacturing facility prior to renovations performed by Saleen to manufacture the Ford GT (which occurred between 2003 and 2006). Prior to use by Stanley, the building was the headquarters of the AMT Corporation, known by many as the premier manufacturer of 1:25th scale model cars in the 1950s, 1960s and 1970s. The plant was last used principally for production of the Saleen S331 Sport Truck, and various models of Saleen Mustangs. Additionally, following Steve Saleen's departure from the company, the core of Saleen's exterior styling and engineering was relocated to Saleen, Troy.\nManufacturing Facilities.\nSSV boasts a single assembly line outfitted to accommodate mixed-product production, a high-efficiency paint shop capable of high-bake paint cure processes, fabrication shop, and specialty car assembly area. Saleen also conducted painting operations for the Dodge Viper in the paint shop at Saleen Special Vehicles. Based upon the production rates achieved during the manufacture of the Ford GT, Saleen Special Vehicles is capable of producing as many as 15 complete vehicles per day.\nShow-Car Facilities.\nSSV houses a multitude of specialty facilities configured with a focus upon the creation of vehicles for use in motion pictures and auto shows. SSV offered prototype model and assembly services to other automotive OEM companies.", "Engineering,_Manufacturing": 0.9997839332, "qwen": "Yes"}
{"id": "7964552", "revid": "1105386605", "url": "https://en.wikipedia.org/wiki?curid=7964552", "title": "Preorder economy", "text": "A preorder economy is a type of proposed future economy where the exact demand for goods is known ahead of time, before any material production takes place. It has been discussed within the framework of ecological economics.\nJust-in-time manufacturing.\nCreating a preorder economy has recently been proposed as an economic efficiency solution to the environmental problems facing modern society. These environmental challenges are believed to be caused in part by unsustainable levels of production, consumption and advertising related to the imperfect exchange of information in market economies. Therefore, preorder economy theory advocates using the Internet as the means to coordinate all production with existing consumer desires, so that almost nothing is made which does not have someone ready to buy it. This is the idea of just in time manufacturing taken to its logical end.\nReferences.\nStanley, Conrad. (2006) \"The Preorder Economy: Coordinating Supply and Demand on the Way to a Sustainable Future\", International Journal of Environment, Workplace and Employment, Vol. 2, Nos. 2/3, pp. 180–205.", "Engineering,_Manufacturing": 0.9950029254, "qwen": "Yes"}
{"id": "2602582", "revid": "1126738558", "url": "https://en.wikipedia.org/wiki?curid=2602582", "title": "TO-220", "text": "The TO-220 is a style of electronic package used for high-powered, through-hole components with pin spacing. The \"TO\" designation stands for \"transistor outline\". TO-220 packages have three leads. Similar packages with two, four, five or seven leads are also manufactured. A notable characteristic is a metal tab with a hole, used to mount the case to a heatsink, allowing the component to dissipate more heat than one constructed in a TO-92 case. Common TO-220-packaged components include discrete semiconductors such as transistors and silicon-controlled rectifiers, as well as integrated circuits.\nTypical applications.\nThe TO-220 package is a \"power package\" intended for power semiconductors and an example of a through-hole design rather than a surface-mount technology type of package. TO-220 packages can be mounted to a heat sink to dissipate several watts of waste heat. On a so-called \"infinite heat sink\", this can be 50 W or more. The top of the package has a metal tab with a hole used to mount the component to a heat sink. Thermal compound is often applied between package and heatsink to further improve heat transfer.\nThe metal tab is often connected electrically to the internal circuitry. This does not normally pose a problem when using isolated heatsinks, but an electrically-insulating pad or sheet may be required to electrically isolate the component from the heatsink if the heatsink is electrically conductive, grounded or otherwise non-isolated. Many materials may be used to electrically isolate the TO-220 package, some of which have the added benefit of high thermal conductivity.\nIn applications that require a heatsink, damage or destruction of the TO-220 device due to overheating may occur if the heatsink is dislodged during operation.\nA heatsinked TO-220 package dissipating 1 W of heat will have an internal (junction) temperature typically 2 to 5 °C higher than the package's temperature (due to the thermal resistance between the junction and the metal tab), and the metal tab of the TO-220 package will typically have a temperature 1 to 60 °C higher than the ambient temperature, depending on the type of heatsink (if any) used.\nThe junction-to-case thermal resistance of a TO-220 packaged device (which typically matters less than the case-to-ambient thermal resistance), depends on the thickness and the area of the semiconductor die inside the package, typically in a range between 0.5 °C/W and 3 °C/W (according to one textbook) or 1.5 °C/W and 4 °C/W (according to another).\nIf more heat needs to be dissipated, devices in the also widely used TO-247 (or TO-3P) package can be selected. TO-3P has a typical junction-to-ambient (heatsink) thermal resistance of only about 40 °C/W, and its TO-3PF variant a slightly lower one. Further increase of heat dissipation capability is possible with power modules.\nWhen a TO-220 package is used without a heatsink, the package acts as its own heatsink, and the heatsink-to-ambient thermal resistance in air for a TO-220 package is approximately 70 °C/W.\nVariations.\nThe TO-220 family of outlines is defined by the JEDEC organization. There are a number of variations on this outline, such as:\nSometimes the designation is followed by the number of leads, as in TO-220AB-5L for five leads, etc.\nThere also some vendor-specific variations such as International Rectifier's SUPER-220, which dispenses with the hole in favor of clip-mounting, thus claiming TO-247-like thermal performance in a TO-220 footprint.\nCommon components that use the TO-220 package.\nThe TO-220 case is found on semiconductor devices handling less than 100 amperes and operating at less than a few hundred volts. These devices operate at DC or relatively low (audio) frequencies, since the TO-220 package is not intended for devices operating at radio frequencies. In addition to bipolar, bipolar Darlington, and power MOSFET transistors, the TO-220 case is also used for fixed and variable linear voltage regulator integrated circuits, and for Schottky diode pairs.", "Engineering,_Manufacturing": 0.9999662638, "qwen": "Yes"}
{"id": "14103070", "revid": "1169410267", "url": "https://en.wikipedia.org/wiki?curid=14103070", "title": "Vendor", "text": "In a supply chain, a vendor, supplier, provider or a seller, is an enterprise that contributes goods or services. Generally, a supply chain vendor manufactures inventory/stock items and sells them to the next link in the chain. Today, these terms refer to a supplier of any goods or service.\nDescription.\nA vendor is a supply chain management term that means anyone who provides goods or services of experience to another entity. Vendors may sell B2B (business-to-business; i.e., to other companies), B2C (business to consumers or Direct-to-consumer), or B2G (business to government). Some vendors manufacture inventoriable items and then sell those items to customers, while other vendors offer services or experiences.\nThe term vendor and the term supplier are often used indifferently. The difference is that the vendors \"sells\" the goods or services while the supplier \"provides\" the goods or services. In most of business context, except retail, this difference has no impact and words are interchangeable.\nTypically vendors are tracked in either a finance system or a warehouse management system.\nVendors are often managed with a vendor compliance checklist or vendor quality audits, and these activities can be effectively managed by software tools.\nPurchase orders are usually used as a contractual agreement with vendors to buy goods or services.\nVendors may or may not function as distributors or manufacturers of goods. If vendors are also manufacturers, they may either build to stock or build to order.\n\"Vendor\" is often a generic term, used for suppliers of industries from retail sales to manufacturers to city organizations. The term generally applies only to the immediate seller, or the organization that is paid for the goods, rather than to the original manufacturer or the organization performing the service if it is different from the immediate supplier.\nTypes.\nThere are four basic sorts of vendors in the supply chain, and the companies and business owners play diverse responsibilities.\nManufacturers: A raw material, when transformed into finished goods, is with the help of the manufacturers. \nRetailer: A retailer is a reseller who sells things in a store or online, such as apparel, office supplies, street vendors selling hot dogs, and so on. \nA Service Provider provides a service, such as maintenance or labour, to customers. Consulting and janitorial services and many other such are two examples.\nA Wholesaler sources products from manufacturers and resells them to retail establishments, distributors, and other buyers. They serve as a crucial intermediary in the supply chain, offering competitive pricing and convenient purchasing options.\nThere must be a vendor relationship with a supplier if a small firm or a major organization wants to resell a product. Vendor registration entails several steps in the process, including completing a credit application, placing a company credit card on file for payments, giving them your company phone number, and establishing payment terms.", "Engineering,_Manufacturing": 0.9995497465, "qwen": "Yes"}
{"id": "14115222", "revid": "19295592", "url": "https://en.wikipedia.org/wiki?curid=14115222", "title": "Featherboard", "text": "A featherboard is a safety device used when working with stationary routers or power saws such as table saws or bandsaws. The purpose of a featherboard is to apply pressure against a workpiece, keeping it flat against a machine table or fence.\nFeatherboard shapes and sizes vary depending on the tasks for which they are intended. A serviceable featherboard can be shop-fabricated from an approximately 3/4 × 3 × 11 inch piece of straight grained, defect-free wood cut crosswise at a 45-degree angle on one end. Several parallel cuts in the direction of the grain create fingers or \"feathers\" that flex in the direction of workpiece travel, preventing the workpiece from being dragged backwards by blade friction.\nFeatherboards are also useful for edge jointing, and making moulding on router tables.", "Engineering,_Manufacturing": 0.9994655252, "qwen": "Yes"}
{"id": "6666867", "revid": "24880950", "url": "https://en.wikipedia.org/wiki?curid=6666867", "title": "Planning horizon", "text": "The planning horizon is the amount of time an organization will look into the future when preparing a strategic plan. Many commercial companies use a five-year planning horizon, however a general Planning horizon is around one year. Other organizations such as the Forestry Commission in the UK have to use a much longer planning horizon to form effective plans.\nIn manufacturing, a planning horizon is a future time period during which departments that support production will plan production work and determine material requirements.\nIn economics, a planning horizon is the length of time an individual plans ahead. It's important in the quest for total value, as opposed to short term pleasure consumption.", "Engineering,_Manufacturing": 0.9998323321, "qwen": "Yes"}
{"id": "2870761", "revid": "40473489", "url": "https://en.wikipedia.org/wiki?curid=2870761", "title": "Process costing", "text": "Process costing is an accounting methodology that traces and accumulates direct costs, and allocates indirect costs of a manufacturing process. Costs are assigned to products, usually in a large batch, which might include an entire month's production. Eventually, costs have to be allocated to individual units of product. It assigns average costs to each unit, and is the opposite extreme of Job costing which attempts to measure individual costs of production of each unit. Process costing is usually a significant chapter. It is a method of assigning costs to units of production in companies producing large quantities of homogeneous products.\nProcess costing is a type of operation costing which is used to ascertain the cost of a product at each process or stage of manufacture. CIMA defines process costing as \"The costing method applicable where goods or services result from a sequence of continuous or repetitive operations or processes. Costs are averaged over the units produced during the period\".\nProcess costing is suitable for industries producing homogeneous products and where production is a continuous flow. A process can be referred to as the sub-unit of an organization specifically defined for cost collection purpose.\nThe importance of process costing.\nCosting is an important process that many companies engage in to keep track of where their money is being spent in the production and distribution processes. Understanding these costs is the first step in being able to control them. It is very important that a company chooses the appropriate type of costing system for their product type and industry. One type of costing system that is used in certain industries is process costing that varies from other types of costing (such as \njob costing) in some ways. In process costing unit costs are more like averages, the process-costing system requires less bookkeeping than does a job-order costing system. Thus, some companies often prefer to use the process-costing system.\nWhen is process costing applied?\nProcess costing is appropriate for companies that produce a continuous mass of like units through series of operations or process. Also, when one order does not affect the production process and a standardization of the process and product exists. However, if there are significant differences among the costs of various products, a process costing system would not provide adequate product-cost information. Costing is generally used in such industries such as petroleum, coal mining, chemicals, textiles, paper, plastic, glass, food, banks, courier, cement, and soap.\nReasons for use.\nCompany units of product in a given period of time.\nProcess cost procedures.\nThere are four basic steps in accounting for Process cost:\nThe journal entries for process costing are the same as those for job-order costing with one exception. The entry to transfer cost from one work-in-process account to another is:\nWork-in-process inventory-second department Debit (Left)\nWork-in-process-first department Credit (Right)\ne.g.(1) Micro Labs Company produces house paint in two processing departments: the Mixing Department which mixes the paint colors and the Finishing Department which puts the paint in containers and labels them. The following information related to the company’s operation for October follows:\nA) Raw materials were issued for use in production: Mixing department, $551,000, and the Finishing department, $629,000.\nB) Direct labor costs incurred: Mixing department $230,000, and Finishing department $270,000. C) Manufacturing overhead cost applied: Mixing department $665,000, and Finishing department, $405,000. D) The cost of the mixed paint transferred from the Mixing department to the Finishing department was $1,850,000. E) Paint that had been prepared for shipping was transferred from the Finishing department to Finished Goods. Cost of the transferred paint was $3,200,000.\nRequired: Prepare journal entries to record items A) through E) above.\nSolution(1):\n –Work in Process – Mixing 551,000\n –Work in Process – Finishing 629,000\n –Raw Materials 1,180,000\n –Work in Process – Mixing 230,000\n –Work in Process – Finishing 270,000\n –Wages and Salaries Payable 500,000\n –Work in Process – Mixing 665,000\n –Work in Process – Finishing 405,000\n –Manufacturing Overhead 1,070,000\n –Work in Process – Finishing 1,850,000\n –Work in Process – Mixing 1,850,000\n –Finished Goods 3,200,000\n –Work in Process – Finishing 3,200,000\ne.g.(2) Larney Corporation uses process costing. A number of transactions that occurred in June are listed below. As follows:\nA) Raw materials that cost $38,200 are withdrawn from the storeroom for use in the Mixing Department. B) Direct labor costs incurred $36,500,in the Mixing Department. C) Manufacturing overhead of $42,100 is applied in the Mixing Department. D) Units with a carrying cost of $112,400 finish processing in the Mixing Department and are transferred to the Drying Department for further processing. E) Units with a carrying cost of $143,800 finish processing in the Drying Department, the final step in the production process, and are transferred to the finished goods warehouse. F) Finished goods with a carrying cost of $138,500\nRequired: Prepare journal entries to record items A) through F).\nSolution (2):\n –work in process-mixing department $38,200\n —raw materials $38,200 \n –work in process $36,500 \n –salaries/wages payable $36,500 \n –work in process-mixing department $42,100 \n –manufacturing overhead $42,100 \n –work in process-drying department. $112,400\n –work in process mixing department $112,400\n –finished goods $143,800 \n –work in process-drying department $143,800 \n -costs of goods sold $138,500\n –finished goods $138,500\nOperation cost in batch manufacturing.\nBatch costing is a modification of job costing. When production is repetitive nature and consists of a definite number of articles, batch is used. In batch costing, the most important problem is to determine the optimum size of the batch that follows the fact that production of two elements of costs:", "Engineering,_Manufacturing": 0.9999032021, "qwen": "Yes"}
{"id": "2874293", "revid": "46228624", "url": "https://en.wikipedia.org/wiki?curid=2874293", "title": "Single-minute exchange of die", "text": "Single-minute digit exchange of die (SMED) is one of the many lean production methods for reducing inefficiencies in a manufacturing process. It provides a rapid and efficient way of converting a manufacturing process from running the current product to running the next product. This is key to reducing production lot sizes, and reducing uneven flow (Mura), production loss, and output variability.\nThe phrase \"single minute\" does not mean that all changeovers and startups should only take \"one\" minute, rather, it should take less than 10 minutes (\"single-digit minute\"). A closely associated yet more difficult concept is one-touch exchange of die (OTED), which says changeovers can and should take less than 100 seconds. A die is a tool used in manufacturing. However SMED's utility is not limited to manufacturing (see value stream mapping).\nHistory.\nFrederick Winslow Taylor analyzed non-value-adding parts of setups in his 1911 book, \"Shop Management\" (page 171). However, he did not create any method or structured approach around it.\nFrank Bunker Gilbreth studied and improved working processes in many different industries, from bricklaying to surgery. As part of his work, he also looked into changeovers. His book \"Motion Study\" (also from 1911) described approaches to reduce setup time.\nEven Henry Ford's factories were using some setup reduction techniques. In the 1915 publication \"Ford Methods and Ford Shops\", setup reduction approaches were clearly described. However, these approaches never became mainstream. For most parts during the 20th century, the economic order quantity was the gold standard for lot sizing.\nThe JIT workflow of Toyota had this problem of tools changeover took between two and eight hours, Toyota could neither afford the lost production time nor the enormous lot sizes suggested by the economic order quantity. Lot reduction and set up time reduction had actually been ongoing in TPS since 1945 when Taiichi Ohno became manager of the machine shops in Toyota. On a trip to the US in 1955, Taiichi Ohno observed Danly stamping presses with rapid die change capability. Subsequently, Toyota bought multiple Danly presses for the Motomachi plant. And Toyota started to work on improving the changeover time of their presses. This was known as \"Quick Die Change\", or \"QDC\" for short. They developed a structured approach based on a framework from the US World War II \"Training within Industry\" (TWI) program, called ECRS – Eliminate, Combine, Rearrange, and Simplify.\nOver time they reduced these changeover times from hours to fifteen minutes by the 1960s, three minutes by the 1970s and then just 180 seconds by 1990s.\nDuring the late 1970s, when Toyota's method was already well refined, Shigeo Shingo participated in one QDC workshop. After he started to publicize details of the Toyota Production System without permission, the business connection was terminated abruptly by Toyota. Shingo moved to the US and started to consult on lean manufacturing. Besides claiming to have invented this quick changeover method (among many other things), he renamed it \"Single Minute Exchange of Die\" or, in short, SMED. The \"Single Minute\" stands for a single digit minute (i.e., less than ten minutes). He promoted TPS and SMED in US.\nExample.\nToyota found that the most difficult tools to change were the dies on the large transfer-stamping machines that produce car vehicle body parts. The dies – which must be changed for each model – weigh many tons, and must be assembled in the stamping machines with tolerances of less than a millimeter, otherwise the stamped metal will wrinkle, if not melt, under the intense heat and pressure.\nWhen Toyota engineers examined the change-over, they discovered that the established procedure was to stop the line, let down the dies by an overhead crane, position the dies in the machine by human eyesight, and then adjust their position with crowbars while making individual test stampings. The existing process took from twelve hours to almost three days to complete.\nToyota's first improvement was to place precision measurement devices on the transfer stamping machines, and record the necessary measurements for each model's die. Installing the die against these measurements, rather than by human eyesight, immediately cut the change-over to a mere hour and a half.\nFurther observations led to further improvements – scheduling the die changes in a standard sequence (as part of FRS) as a new model moved through the factory, dedicating tools to the die-change process so that all needed tools were nearby, and scheduling use of the overhead cranes so that the new die would be waiting as the old die was removed. Using these processes, Toyota engineers cut the change-over time to less than 10 minutes per die, and thereby reduced the economic lot size below one vehicle.\nThe success of this program contributed directly to just-in-time manufacturing which is part of the Toyota Production System. SMED makes Load balancing much more achievable by reducing economic lot size and thus stock levels.\nEffects of Implementation.\nShigeo Shingo, who created the SMED approach, claims that in his data from between 1975 and 1985 that average setup times he has dealt with have reduced to 2.5% of the time originally required; a 40 times improvement.\nHowever, the power of SMED is that it has a lot of other effects which come from systematically looking at operations; these include:\nImplementation Techniques.\nShigeo Shingo recognizes eight fundamental techniques that should be considered in implementing SMED.\nNB External setup can be done without the line being stopped whereas internal setup requires that the line be stopped.\nHe suggests that SMED improvement should pass through four conceptual stages:\nA) ensure that external setup actions are performed while the machine is still running,\nB) separate external and internal setup actions, ensure that the parts all function and implement efficient ways of transporting the die and other parts,\nC) convert internal setup actions to external,\nD) improve all setup actions.\nFormal method.\nThere are seven basic steps to reducing changeover using the SMED system:\nThis diagram shows four successive runs with learning from each run and improvements applied before the next.\nThe SMED concept is credited to Shigeo Shingo, one of the main contributors to the consolidation of the Toyota Production System, along with Taiichi Ohno.\nKey Elements to Observe.\nLook for:\nRecord All Necessary Data\nParallel operations using multiple operators By taking the 'actual' operations and making them into a network which contains the dependencies it is possible to optimise task attribution and further optimize setup time. Issues of effective communication between the operators must be managed to ensure safety is assured where potentially noisy or visually obstructive conditions occur.\nParallel operations using multiple operators By taking the 'actual' operations and making them into a network which contains the dependencies it is possible to optimise task attribution and further optimize setup time. Issues of effective communication between the operators must be managed to ensure safety is assured where potentially noisy or visually obstructive conditions occur.", "Engineering,_Manufacturing": 0.9999036789, "qwen": "Yes"}
{"id": "22375091", "revid": "1001916319", "url": "https://en.wikipedia.org/wiki?curid=22375091", "title": "Resin dispensing", "text": "A resin dispensing system is a technical installation to process casting resin for the purpose of filling, sealing, covering or soaking technical parts, especially in the field of electricity and electronics like transformers, LCDs and other devices of various size.\nDue to progressing miniaturization and introduction of electronics into new areas, quality requirements for the parts are rising, and thus the quality of dispensing must be increased as well. To obtain the required quality, on one hand, the resin system has to be developed and optimized accordingly. On the other hand, the resin dispensing system has to work more and more precisely to obtain best dispensing. Because of continuously increasing cost pressure, casting devices must be capable of increased quality, while also becoming faster and more reliable.\nRequirements for good dispensing.\nFirst of all, by dispensing, electrical and electronic parts have to be insulated reliably and penetration of moisture has to be excluded totally. Very often heat has to be conducted out from the part properly, an attribute that can be improved by the choice of an appropriate resin e.g. epoxy, polyurethane or silicone.\nProcess steps in a dispensing system.\nIn a dispensing system the following processes have to be performed:\nA good resin dispensing system provides high quality casting of the same high standard even during long series in mass production.\nConditioning.\nSeveral properties of the resin mix, with or without filler material, one component or two components (resin + hardener), are crucial for the quality of the product:\nEven distribution of the fillers without setting is maintained by ongoing stirring.\nAir and moisture are eliminated by evacuating the material tanks.\nElevated temperature is reached and maintained by thoroughly controlled heating of the tanks, the material feeding lines, the pumps and metering heads. In filled, complex resin mixes conditioning is especially crucial for the quality of the product.\nMaterial transportation.\nWhich kind of feeding pump has to be used depends mainly on the viscosity of the material and the abrasiveness of the fillers.\nFor low to medium viscous material:\nGear pumps are not fit for abrasive material\nFor highly viscous material follower plate pumps are connected with an eccentric screw pump or a scooping piston pump. Metering is controlled for mass, time, and volume to determine the amount of resin dispensed.\nMetering by mass.\nWeighing provides very exact determination of amount, but it lengthens the cycle time. Also, a scale within a production line can be quite sensitive to malfunction and hard to use on boards populated with many parts. Because of these issues, this method is rarely used.\nMetering by using Volume.\nGetting constant volume is, technically, relatively simple and metering systems relying on constant volume dispensing therefore are especially simple and reliable.\nA very good way is the use of piston metering heads. The ratio of resin to hardener can be determined exactly by the ratio of the width of two separate pistons, one for resin, one for hardener, where both pistons are pushed simultaneously. The amount is determined by a common stopper, limiting the stroke of both pistons equally.\nState of the art (2009) are metering volumes from 0,01 mL to about 250 mL, may be even more.\nMetering by using time.\nThis method demands that the appropriate pumps provide precisely constant flow of the material. Flow of material is started by a controlled valve and stopped after a certain time.\nThis method is especially susceptible to metering flaws, because the slightest change in flow speed causes different amounts of dispensed resin and/or hardener. Providing for an absolutely constant flow calls for relatively high electronic complexity, but provides much greater flexibility in adjusting the proportions of hardener to resin.\nMixing.\nIn two component resins, thorough mixing is crucial to obtain equal reaction between resin and hardener throughout all the material. There are three possible ways to mix:\nStatic mixing tube.\nThe components meet in a mixing tube made of plastic. The tube contains immobile walls to divide and bring together the material several times, mixing resin and hardener by this process. The mixing tube is not cleaned after use, but discarded.\nDynamic mixing.\nThe components meet in a mixing chamber, usually made of stainless steel and there they are mixed homogeneously by a rotating blender. To optimize mixing, the rotational speed can be controlled electronically. Mixing chamber and blender have to be cleaned with a special cleaning fluid to be used again. Usually this happens automatically.\nStatic-dynamic mixing.\nA mixing tube made from plastic contains a helix driven by an external motor. This method is rarely used.\nDispensing.\nTo provide for best casting, the part and the dispensing unit have to be moved relatively to each other. In principle there are two ways:\nFor many applications, dispensing can only be done successfully in vacuum. This is true especially for parts with a large undercut, i.e. soaking of transformation coils. In such cases bubble free dispensing can only be obtained in vacuum. For this purpose dispensing systems are equipped with vacuum chambers. To shorten cycle times there can be an airlock at the entrance and one at the exit. In vacuum dispensing only systems where the parts are moving and the dispenser remains in place can be built reasonably.\nFor the production of series, dispensing systems with multifold metering heads can be used. At this time (2006) there are systems running capable to do up to thirty dispensing acts simultaneously.\nVariability of dispensing.\nThe most simple way of dispensing is, to cast a certain amount of resin into one spot of a not moving part. Such simple systems sometimes are called metering systems. Centrifugal casting tables are available. The mold is fixed on this rotary table and while the resin mix is dispensed into the mold, centrifugal force ensures a solid, clean bubble free fill. The part is also stronger due to stress hardening. In some cases, the parts are equal to pressure injection dispensing.\nBy using adequate controls, many variations of casting are available. For instance, dams can be cast in different forms. Cast from highly viscous, thixotropic material, dams can be filled with resin of low viscosity (dam & fill). The deposition speed of the resin can be varied during casting or casting can be done in several portions. At the same time the part can execute complex movements. Using additional options of that kind make it possible to solve difficult casting problems.\nImplementation of Dispensing into a Production Line.\nA casting system can be combined with many different production steps within a production line. So casting becomes an integrated part of the whole manufacturing of a part. To account for the delicate requirements of dispensing in all production steps in the best way, the most significant manufacturers are active in automation as well. The newest development in this area is the design of a production line from prefabricated, ideally adapted modules. This speeds up the development of individual solutions and decreases their costs.\nExamples for Application of Dispensing.\nMore and more parts are sealed by casting, because this accelerates the production and increases the lifetime and functionality of the parts. On the other side, sealed parts cannot be repaired.\nSealing of electronic parts.\nElectronic units, plugged into a board, usually are sealed by resin to protect them from environmental influences and from mechanical damage. In those cases dispensing usually means just to fill up a form, a relatively simple process.\nProduction of LEDs.\nLight-emitting diodes are produced in fully automated lines. Part of it is the dispensing in transparent plastics. Here short working cycles are of great significance to lower the price of the little lights. This an example for the use of multiple metering heads.\nSoaking of electrical windings.\nIn electric motors and in transformers, multiple layers of windings of fine copper wire are essential. Today they usually are soaked in resin to protect them from environmental influences and to improve insulation from each other. Because of the fine structure of the space between the windings and because of much undercut, soaking of such windings puts highest demands to the used dispensing device.", "Engineering,_Manufacturing": 1.00000453, "qwen": "Yes"}
{"id": "22375093", "revid": "21763262", "url": "https://en.wikipedia.org/wiki?curid=22375093", "title": "Resin casting", "text": "Resin casting is a method of plastic casting where a mold is filled with a liquid synthetic resin, which then hardens. It is primarily used for small-scale production like industrial prototypes and dentistry. It can be done by amateur hobbyists with little initial investment, and is used in the production of collectible toys, models and figures, as well as small-scale jewellery production.\nThe synthetic resin for such processes is a monomer for making a plastic thermosetting polymer. During the setting process, the liquid monomer polymerizes into the polymer, thereby hardening into a solid.\nSingle-monomer resins may be used in the process, which form homopolymers (polymers containing only one type of polymer). In such uses, the \"curing agent\" mixed with the resin contains what is loosely referred to as a \"catalyst,\" but which is more technically an initial source of free radicals (such as MEKP) to act as an initiator in a free-radical chemical chain reaction polymerization. Alternately, resin casting may be accomplished with a resin plus a nearly equal amount of a \"hardener\" liquid (as in many epoxy resin or polyester resin systems), which functionally contains a second polymer, for use in forming a final product plastic which is a copolymer. Copolymers contain two different alternating chemical entities in the final polymer molecule.\nProcess.\nMost commonly a thermosetting resin is used that polymerizes by mixing with a curing agent (polymerization catalyst) at room temperature and normal atmospheric pressure. The resins are named by analogy with plant resins, but are synthetic monomers for making polymer plastics. The so-called synthetic resins used include polystyrene resin, polyurethane resin, epoxy resin, unsaturated polyester resin, acrylic resin and silicone resin.\nEpoxy resin has a lower viscosity than polyurethane resin ; polyester resin also shrinks markedly while curing. Acrylic resin, in particular the methyl methacrylate type of synthetic resin, produces acrylic glass (also called PMMA, Lucite, Plexiglass), which is not a glass but a plastic polymer that is transparent, and very hard. It is suitable for embedding objects (such as, for example, acrylic trophies), for display purposes. Styrene is a similar liquid monomer at room temperature, which will also polymerize into clear glass-like polystyrene plastic, with addition of a suitable catalyst.\nA flexible mold can be made of latex rubber, room temperature vulcanized silicone rubber, of which there are two types:Tin catalysed (sometimes called condensation cured due to the alcohols weeping out as a by product of the reaction) or Platinum (or addition cured, thus no byproduct) catalysed. Other similar materials can be used at relatively low cost, but can only be used for a limited number of castings.\nThe simplest method is gravity casting where the resin is poured into the mold and pulled down into all the parts by gravity. When the two part resin is mixed air bubbles tend to be introduced into the liquid which can be removed in a vacuum chamber. The casting can also be done in a vacuum chamber (when using open molds) to either extract these bubbles, or in a pressure pot, to reduce their size to the point where they aren't visible. Specialist equipment can enable closed molds to be filled whilst under vacuum, a process known as resin vacuum casting, where air and gas bubbles are completely removed from the cast part. Pressure and/or centrifugal force can be used to help push the liquid resin into all details of the mold. The mold can also be vibrated to expel bubbles.\nEach unit requires some amount of hands-on labor, making the final cost per unit produced fairly high. This is in contrast to injection molding where the initial cost of creating the metal mold is higher, but the mold can be used to produce a much higher number of units, resulting in a lower cost per unit.\nCollectibles and models.\nResin casting is used to produce collectible and customized toys and figures like designer toys, garage kits and ball-jointed dolls, as well as scale models, either individual parts or entire models of objects like trains, aircraft or ships. They are generally produced in small quantities, from the tens to a few hundred copies, compared to injection-molded plastic figures which are produced in many thousands. Resin casting is more labor intensive than injection molding, and the soft molds used are worn down by each cast. The low initial investment cost of resin casting means that individual hobbyists can produce small runs for their own use, such as customization, while companies can use it to produce small runs for public sale.\nThe creation of a toy or figure start with the traditional sculpting process where the artist designs a clay sculpture. Where appropriate, for example when making a garage kit, the sculpture is dissected into several parts like head, torso, arms and legs. A flexible mold made from room temperature vulcanized (RTV) silicone rubber is made for each part.\nAfter the mold has been made, a synthetic resin - such as polyurethane or epoxy - mixed with a curing agent, is poured into each mold cavity. Mixing the two liquid parts causes an exothermic reaction which generates heat and within minutes causes the material to harden, yielding castings or copies in the shape of the mold into which it has been poured. The molds are commonly half-divided (like the hollowed chocolate Easter eggs with candy inside) and a release agent may be used to make removal of the hardened/set resin from the mold easier. The hardened resin casting is removed from the flexible mold and allowed to cool.\nDue to aggressive nature of most compounds used for casting and the high temperature of the reaction the mold gradually degrades and loses small details. Typically, a flexible mold will yield between 25 and 100 castings depending upon the size of the part, the intensity of the heat generated.\nDepending on the type of product it may then be cut or sanded to remove any casting artefacts like sprues and seams. Some products are also assembled and painted, while some models and kits, which are intended for the consumer to assemble, are left unfinished.\nThe ability of RTV silicone molds to reproduce even the tiniest detail means that many of these low volume castings are of very high quality. Quality of both original masters and resin castings varies due to differences in creator's skill, as well as casting techniques.", "Engineering,_Manufacturing": 0.9997811913, "qwen": "Yes"}
{"id": "22400443", "revid": "1234701", "url": "https://en.wikipedia.org/wiki?curid=22400443", "title": "Elastomeric connector", "text": "Elastomeric connectors, also known by the registered trademark ZEBRA connectors, consist of alternating conductive and insulating regions in a rubber or elastomer matrix to produce overall anisotropic conductive properties. The original version consisted of alternating conductive and insulating layers of silicone rubber, cut crosswise to expose the thin layers. They provide high-density redundant electrical paths for high reliability connections. One of the first applications was connecting thin and fragile glass liquid-crystal displays (LCDs) to circuit boards in electronic devices, as little current was required.\nBecause of their flexibility, they excel in shock and anti-vibration applications. They can create a gasket-like seal for harsh environments. Conductor material possibilities include carbon, silver, and gold. The length, width and height may be specified as well as the stripe pitch. Frequently a recess with ribs is specified that captures and provides the elastomer reference surface for alignment (while allowing the lateral dimension of the elastomer to increase as it is compressed) with a deflection stop to control the final part separation, and alignment pins for substrate alignment.\nThey are used in two ways:\nA \"matrix\" version consists of short, fine, metallic wires, 300 to 2,000 per square centimeter, aligned parallel but not touching each other, embedded in a rubber sheet. The wires can either protrude slightly from the top and bottom of the rubber sheet, or be curved and flush with the top and bottom planes; the latter is used for repeated assembly or inspection.", "Engineering,_Manufacturing": 0.9999376535, "qwen": "Yes"}
{"id": "10403211", "revid": "134766", "url": "https://en.wikipedia.org/wiki?curid=10403211", "title": "Case (goods)", "text": "A case of some merchandise is a collection of items packaged together. A case is not a strict unit of measure. For consumer foodstuff such as canned goods, soda, cereal, and such, a case is typically 24 items, however cases may range from 12 to 36, typically in multiples of six. For larger bottles such as gallon jugs, a case is typically 4.\nBook manufacture.\nThe term \"case binding\" in the book manufacturing industry refers to a collection of pages contained in a \"case\" which is attached to it. (There are also cases for books e.g. slipcases which merely enclose a book.) The original \"case\" is often now called simply the \"binding\", although the integrated manufacturing process still uses the term \"case\" to refer to the hard cover and spine.", "Engineering,_Manufacturing": 0.9930388331, "qwen": "Yes"}
{"id": "3073484", "revid": "42425010", "url": "https://en.wikipedia.org/wiki?curid=3073484", "title": "Productionisation", "text": "Productionisation (Commonwealth English) or productionization (American English) is the process of turning a prototype of a design into a version that can be more easily mass-produced. It is mostly a necessary step in the development of any product, since it is rare that the initial design is free from flaws or construction methods which make it difficult or more expensive to manufacture.\nPrototypes are very often constructed by hand, or with more limited tooling. This is done to save costs where the design may not even be subsequently approved for manufacture. Once the go-ahead for a production run is given, the much more costly production tooling can be ordered. At this stage, the design itself may need to be reworked or altered to streamline production. The goal is to reduce costs as much as possible at the assembly stage, since costs will be multiplied by the number of units produced. For example, a prototype might be assembled using nuts and bolts, but in production such fasteners might be replaced by captive nuts or threaded holes built into the parts, making assembly much faster, easier and therefore cheaper.\nSometimes limited runs of a design might be manufactured without full productionisation.\nOther examples of productionisation include:\nProductionisation is a term that is increasingly prevalent in Software Development. One reason for this is the popularity of agile type development methods, which often focus on building a prototype solution to develop and refine the product to the business requirements. Prior to putting the system into production, the developers need to ensure the system is robust enough for the target environment with regard to aspects such as error handling, stability, usability, scalability and performance. This process of making the prototype ‘production or enterprise grade’ is often referred to as ‘Productionisation’.", "Engineering,_Manufacturing": 0.9995418787, "qwen": "Yes"}
{"id": "3080690", "revid": "25384948", "url": "https://en.wikipedia.org/wiki?curid=3080690", "title": "Processing medium", "text": "In industrial engineering, a processing medium is a gaseous, vaporous, fluid or shapeless solid material that plays an active role in manufacturing processes - comparable to that of a tool.\nExamples.\nA processing medium for washing is a soap solution, a processing medium for steel melting is a plasma, and a processing medium for steam drying is superheated steam.", "Engineering,_Manufacturing": 0.9999862909, "qwen": "Yes"}
{"id": "47687382", "revid": "4743453", "url": "https://en.wikipedia.org/wiki?curid=47687382", "title": "Tooling U-SME", "text": "Tooling U-SME, formerly Tooling University, is an American non-profit educational technology and blended learning organization that produces learning management system software, certifications and content for the manufacturing industry. Owned by the Society of Manufacturing Engineers (SME) and headquartered in Cleveland, Ohio, Tooling U provides online industrial manufacturing training, development, and competency based apprenticeship programs.\nHistory.\nTooling University, the original online training component of Tooling U-SME, was founded to address the shortage of skilled workers in the manufacturing industry. Tooling U began as a division of Jergens Inc., a workholding and tooling component manufacturer founded in 1942. In 2010, Tooling University was acquired by SME.\nSince the acquisition, Tooling U-SME has spent recent years uniting all of its training products, launching service offering upgrades, and providing niche learning services for specific jobs like welding. The company has also been awarded multiple grants from US government institutions like the Department of Defense and the Department of Labor to develop training programs that support the development of America's workforce in manufacturing.\nCompetency Framework.\nIn early 2014 Tooling U-SME launched the Competency Framework for achieving manufacturing excellence. The Competency Framework is made up of more than 60 job competency models in nine manufacturing functional areas. Each competency model outlines knowledge and skill objectives for production workers, technicians, lead technicians and technologists, and engineers.\nProducts and Services.\nTooling U-SME supplies manufacturers, high schools and technical colleges with in-house and online training resources that are translatable to both certificate programs and associate degrees. Students can choose from over 70 instructor-led programs, and have 24/7 access to more than 450 online courses, covering everything from safety and maintenance to composites and machining.\nCustom Training Content.\nCustom in-house training and educational content for schools and organizations.\nAssessments.\nOnline assessments for evaluating current workforce skills and developing training programs based on filling the gaps.\nCertifications.\nIndustry-backed certifications for lean manufacturing technology, machining technology, advanced manufacturing, and manufacturing engineering, as well as certificate programs for green manufacturing. Tooling U-SME training courses adhere to the National Institute for Metalworking Skills (NIMS) Standards, SME Certified Manufacturing Technologist (CMfgT) certification, Manufacturing Skills Standards Council (MSSC) standards and American Welding Society (AWS) SENSE Level 1 standard.\nOnline bookstore and Knowledge Edge®.\nKnowledge Edge is a subscription service digital library with more than 700 industrial training videos and clips, 1,200 eBooks and eChapters, 16,000 technical papers and 10,000 entries in the Manufacturing Knowledge Base wiki.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "59874449", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=59874449", "title": "Computed axial lithography", "text": "Computed axial lithography is a method for 3D printing based on computerised tomography scans to create objects from photo-curable resin. The process was developed by a collaboration between the University of California, Berkeley and the Lawrence Livermore National Laboratory. Unlike other methods of 3D printing, computed axial lithography does not build models through depositing layers of material, as fused deposition modelling and stereolithography does, instead it creates objects using a series of 2D images projected onto a cylinder of resin. It is notable for its ability to build object much more quickly than other methods using resins and the ability to embed objects within the objects.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1464875", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=1464875", "title": "Product requirements document", "text": "A product requirements document (PRD) is a document containing all the requirements for a certain product.\nIt is written to allow people to understand \"what\" a product should do. A PRD should, however, generally avoid anticipating or defining \"how\" the product will do it in order to later allow interface designers and engineers to use their expertise to provide the optimal solution to the requirements.\nPRDs are most frequently written for software products, but they can be used for any type of product and also for services. \nTypically, a PRD is created from a user's point-of-view by a user/client or a company's marketing department (in the latter case it may also be called a Marketing Requirements Document (MRD)). The requirements are then analyzed by a (potential) maker/supplier from a more technical point of view, broken down and detailed in a Functional Specification (sometimes also called Technical Requirements Document).\nComponents.\nTypical components of a product requirements document (PRD) are:\nNot all PRDs have all of these components. In particular, PRDs for other types of products (manufactured goods, etc.) will eliminate the software-specific elements from the list above, and may add in additional elements that pertain to their domain, e.g. manufacturing requirements.", "Engineering,_Manufacturing": 0.993334353, "qwen": "Yes"}
{"id": "1942626", "revid": "14841472", "url": "https://en.wikipedia.org/wiki?curid=1942626", "title": "Manipulator (device)", "text": "In robotics, a manipulator is a device used to manipulate materials without direct physical contact by the operator. The applications were originally for dealing with radioactive or biohazardous materials, using robotic arms, or they were used in inaccessible places. In more recent developments they have been used in diverse range of applications including welding automation, robotic surgery and in space. It is an arm-like mechanism that consists of a series of segments, usually sliding or jointed called cross-slides, which grasp and move objects with a number of degrees of freedom.\nIn industrial ergonomics a manipulator is a lift-assist device used to help workers lift, maneuver and place articles in process that are too heavy, too hot, too large or otherwise too difficult for a single worker to manually handle. As opposed to simply vertical lift assists (cranes, hoists, etc.) manipulators have the ability to reach in to tight spaces and remove workpieces. A good example would be removing large stamped parts from a press and placing them in a rack or similar dunnage. In welding, a column boom manipulator is used to increase deposition rates, reduce human error and other costs in a manufacturing setting.\nAdditionally, manipulator tooling gives the lift assist the ability to pitch, roll, or spin the part for appropriate placement. An example would be removing a part from a press in the horizontal and then pitching it up for vertical placement in a rack or rolling a part over for exposing the back of the part.\nSpecialized types.\nOne of the types of manipulators is balanced manipulator type MSP-250, controlled by the operator's hand. Such manipulators are used in various industries. Where there are special requirements to protect against fire and explosion, they may be driven by compressed air.\nA welding manipulator can be either open arc or submerged arc. A welding manipulator can be used to weld horizontally and vertically and is ideal for job shops as they are robust, have high production volume capacity and a greater degree of flexibility in product engineering. Welding manipulators are commonly used in pipe and vessel fabrication but can be used in a cladding procedure with the aid of a proper welding fixture.\nExamples.\nExamples of robotic manipulators are:", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "1943888", "revid": "43766726", "url": "https://en.wikipedia.org/wiki?curid=1943888", "title": "GES International", "text": "GES International Limited is an engineering and manufacturing company founded as a sole proprietorship called Goh Electronics Services by Goh Lik Tuan in 1975. It is based in Singapore, Malaysia, China and the United States. It is on the SGX, the Singapore stock exchange, and it is a listed component of the Straits Times Index. In 2006, it became a subsidiary of the Singapore-based Venture Corporation.\nGES has two R&D (Research and Design) centers, in Singapore and Shanghai working in original design manufacturer (ODM) and original equipment manufacturer (OEM).\nGES International performs manufacture and design including ASIC design, hardware design, software design, mechanical design, power management design, technical writing, PCB design, industrial design, etc. in the field of electronics. The company began as a personal computer manufacturer in Asia, manufacturing the Datamini computer.\nGES performs shipping (logistics) and aftermarket services, consisting of repair and warranty services.", "Engineering,_Manufacturing": 0.9998481274, "qwen": "Yes"}
{"id": "1346094", "revid": "525927", "url": "https://en.wikipedia.org/wiki?curid=1346094", "title": "John K. Stewart", "text": "John Kerwin Stewart (November 30, 1870 – June 1, 1916) was an entrepreneur and inventor. He founded the Stewart-Warner Corporation. In his lifetime he founded or purchased several companies and held 82 patents.\nBiography.\nHe was born in 1870 in Hillsborough, New Hampshire. He married Julia Pearl Butler in 1896, the couple had three daughters.\nIn what became training for their futures in manufacturing, Stewart and Thomas J. Clark worked at a factory in New Hampshire that produced horse clipping machinery. The lifelong friends later moved to Providence, Rhode Island, and worked for the Brown & Sharpe Manufacturing Company. Then, in approximately 1890, the two traveled to Chicago, Illinois, where they entered into partnership and manufactured horse clippers, sheep clippers, bicycle handle bars and flexible shafts among other products.\nHe died on June 1, 1916, in New York City.\nCompanies founded.\nChicago Flexible Shaft Company.\nIn 1893 Stewart & Clark founded the Chicago Flexible Shaft Company (incorporated 1897) to manufacture flexible driveshafts and mechanical sheep shears. Stewart and Charles Timson of Wm. Cooper & Nephews partnered in founding the Cooper-Stewart Sheep Shearing Machinery Co in 1896 and sold the sheep shearing products through this new company.\nIn 1903 Wm. Cooper & Nephews purchased 50% ownership of the Chicago Flexible Shaft Company. In 1908 Wm. Cooper & Nephews purchased the remaining 50% of Chicago Flexible Shaft Company for $400,000. Julia Stewarts nephew remained the president of Chicago Flexible Shaft Company after the sale.\nIn 1910, the Chicago Flexible Shaft Company introduced its first home appliance, an electric iron, under the brand name Sunbeam. The Sunbeam Mixmaster was introduced in 1930. By 1946, Sunbeam appliances had become so successful and widely sold that the company name would change formally to Sunbeam Corporation.\nSterk Manufacturing Company.\nAround 1896 Stewart and Clark founded the Sterk Manufacturing Company which produced speedometers and automobile horns. The flexible shafts from the Chicago Flexible Shaft Company were used in the production of cables needed for the speedometers.\nStewart & Clark Manufacturing Company.\nIn 1905 Stewart & Clark Manufacturing Company was founded and acquired all assets of the Sterk Manufacturing Company.\nThe partners erected a small manufacturing plant on Diversey Parkway in Chicago. This plant would eventually grow to a one million square foot (93,000 m²) manufacturing and headquarters facility for Stewart-Warner until the company left Chicago in 1988.\nDue to his patents, Stewart collected $311,000 in royalties, which were calculated at $5 per speedometer sold in 1909.\nUnfortunately, Clark was killed while demonstrating the Stewart speedometer in a Packard during the 1907 Glidden Tour #. Stewart acquired Clarks' share of the company.\nJ.K. Stewart Manufacturing Company.\nDue to the need for the blades of clippers & shears to last longer and remain sharp, Stewart worked with Edward Larson to build a heat treatment furnace for tempering steel. In 1906 the two formed the E.A. Larson & Brothers Company to take advantage of the processes they developed to provide die casting for speedometer production as well as other companies in the area. In 1908, E.A. Larson was reorganized as the J.K. Stewart Manufacturing Company.\nStewart-Warner Speedometer Corporation.\nStewart and rival instrument manufacturer, Warner Instrument Company, were in heated legal battles over patent infringements by both parties. All lawsuits ceased when Stewart bought the Warner Instrument Company in 1912. Stewart-Warner Speedometer Corporation was formed the same year by consolidating the Warner Company with the Stewart & Clark Manufacturing Company. Once again the name changed in 1929 to Stewart-Warner Corporation.\nStewart Phonograph Company.\nA lover of music, Stewart ventured into the phonograph market in 1915. Eventually becoming a division of Stewart-Warner, the phonograph company expanded to include radios, televisions, and the required accessories such as speakers.", "Engineering,_Manufacturing": 0.9998972416, "qwen": "Yes"}
{"id": "1347035", "revid": "486612", "url": "https://en.wikipedia.org/wiki?curid=1347035", "title": "GE Automation & Controls", "text": "General Electric Automation and Controls division combines what was formerly known as GE Intelligent Platforms and Alstom's Power Automation and Controls. In 2019, GE Intelligent Platforms was acquired by Emerson Electric and is now called Machine Automation Solutions.\nGE Automation and Controls produce Programmable Logic Controller (PLC) and Programmable Automation Controller (PAC) based control systems, I/O, and field devices, including support to design, commission and operate industrial assets and operations. Industries served include manufacturing, food and beverage, life sciences, power, oil and gas, mining and metals, water and wastewater, and specialty machinery industries.\nHistory.\nIn 1986, GE Fanuc Automation Corporation was jointly established in the US by FANUC and General Electric (GE). Under the joint venture company, three operating companies, GE Fanuc Automation North America, Inc., in the U.S., GE Fanuc Automation Europe S.A. in Luxembourg, and Fanuc GE Automation Asia Ltd. in Japan were established (the Asian company was established in 1987).\nIn 2007, the company was renamed to GE Fanuc Intelligent Platforms (and GE Fanuc Automation Solutions Europe SA became GE Fanuc Intelligent Platforms Europe SA). GE Fanuc Automation CNC Europe changed its name to Fanuc GE CNC Europe.\nIn 2009, GE and Fanuc agreed to dissolve joint venture and the software, controls and embedded business became part of GE, under the new name GE Intelligent Platforms.\nIn 2015, GE Intelligent Platforms, Inc. changed its name to Automation & Controls upon acquisition of Alstom's Power Automation & Controls business.\nIn 2018, amidst restructuring plans for the whole General Electric group, it was announced that Emerson Electric was to acquire Intelligent Platforms, and the deal was completed on February 1, 2019.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "5030939", "revid": "13286072", "url": "https://en.wikipedia.org/wiki?curid=5030939", "title": "Environmental management system", "text": "An environmental management system (EMS) is \"a system which integrates policy, procedures and processes for training of personnel, monitoring, summarizing, and reporting of specialized environmental performance information to internal and external stakeholders of a firm\".\nThe most widely used standard on which an EMS is based is International Organization for Standardization (ISO) 14001. Alternatives include the EMAS.\nGoals.\nThe goals of EMS are to increase compliance and reduce waste:\nFeatures.\nAn environmental management system (EMS):\nEMS Model.\nAn EMS follows a Plan-Do-Check-Act, or PDCA, Cycle. The diagram shows the process of first developing an environmental policy, planning the EMS, and then implementing it. The process also includes checking the system and acting on it. The model is continuous because an EMS is a process of continual improvement in which an organization is constantly reviewing and revising the system.\nThis is a model that can be used by a wide range of organizations – from manufacturing facilities to service industries to government agencies.\nAccreditation.\nEnvironmental Management Systems can be accredited under ISO 14001.\nOther meanings.\nAn EMS can also be classified as: ", "Engineering,_Manufacturing": 0.9978469014, "qwen": "Yes"}
{"id": "5031634", "revid": "10678181", "url": "https://en.wikipedia.org/wiki?curid=5031634", "title": "2005 UEFA Intertoto Cup", "text": "The 2005 UEFA Intertoto Cup finals were won by Lens, Marseille, and Hamburg. All three teams advanced to the UEFA Cup.\nFirst round.\nSecond leg.\n\"Beitar Jerusalem won 6–4 on aggregate.\"\n\"Gent won 3–2 on aggregate.\"\n\"Pogoń Szczecin won 9–2 on aggregate.\"\n\"Budućnost Podgorica won 7–2 on aggregate.\"\n\"Lokeren won 2–1 on aggregate.\"\n\"Göteborg won 5–2 on aggregate.\"\n\"Varteks won 5–3 on aggregate.\"\n\"Slaven Belupo won 2–0 on aggregate.\"\n\"Neuchâtel Xamax won 9–1 on aggregate.\"\n\"CFR Ecomax Cluj won 7–3 on aggregate.\"\n\"Gloria Bistrița won 16–0 on aggregate.\"\n\"Tampere United won 3–0 on aggregate.\"\n\"ZTS Dubnica won 2–0 on aggregate.\"\n\"Žalgiris won 2–0 on aggregate.\"\n\"Lech Poznań won 4–1 on aggregate.\"\n\"Sturm Graz won 6–1 on aggregate.\"\n\"Dinaburg won 4–1 on aggregate.\"\n\"Pobeda won 3–1 on aggregate.\"\n\"Tescoma Zlín won 1–0 on aggregate.\"\n\"Lombard-Pápa won 3–1 on aggregate.\"\n\"Inter Turku won 4–0 on aggregate.\"\nSecond round.\nSecond leg.\n\"Sigma Olomouc won 1–0 on aggregate.\"\n\"1–1 on aggregate, CFR Ecomax Cluj won in a penalty shootout.\"\n\"Wolfsburg won 5–3 on aggregate.\"\n\"Deportivo La Coruña won 4–2 on aggregate.\"\n\"ZTS Dubnica won 4–1 on aggregate.\"\n\"Slovan Liberec won 7–2 on aggregate.\"\n\"Saint-Étienne won 3–2 on aggregate.\"\n\"Gent won 1–0 on aggregate.\"\n\"Hamburg won 8–2 on aggregate.\"\n\"Slaven Belupo won 4–2 on aggregate.\"\n\"Young Boys won 6–2 on aggregate.\"\n\"Varteks won 6–5 on aggregate.\"\n\"Tampere United won 1–0 on aggregate.\"\n\"Göteborg won 4–2 on aggregate.\"\n\"Žalgiris won 3–2 on aggregate.\"\n\"Lens won 3–1 on aggregate.\"\nThird round.\nSecond leg.\n\"Deportivo La Coruña won 4–0 on aggregate.\"\n\"Žalgiris won 5–4 on aggregate.\"\n\"1–1 on aggregate, Sigma Olomouc won on away goals rule.\"\n\"Marseille won 5–3 on aggregate.\"\n\"Lens won 5–2 on aggregate.\"\n\"1–1 on aggregate, Roda won on away goals rule.\"\n\"Hamburg won 3–0 on aggregate.\"\n\"Valencia won 2–0 on aggregate.\"\n\"Newcastle United won 5–1 on aggregate.\"\n\"Lazio won 4–1 on aggregate.\"\n\"Wolfsburg won 4–0 on aggregate.\"\n\"3–3 on aggregate, CFR Ecomax Cluj won on away goals rule.\"\nSemi–finals.\nSecond leg.\n\"CFR Ecomax Cluj won 7–2 on aggregate.\"\n\"Lens won 4–0 on aggregate.\"\n\"Valencia won 4–0 on aggregate.\"\n\"Hamburg won 4–0 on aggregate.\"\n\"Deportivo La Coruña won 4–2 on aggregate.\"\n\"Marseille won 4–1 on aggregate.\"\nFinals.\nSecond leg.\n\"Lens won 4–2 on aggregate.\"\n\"Marseille won 5–3 on aggregate.\"\n\"Hamburg won 1–0 on aggregate.\"", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "5041589", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=5041589", "title": "Autocollimator", "text": "An autocollimator is an optical instrument for non-contact measurement of angles. They are typically used to align components and measure deflections in optical or mechanical systems. An autocollimator works by projecting an image onto a target mirror and measuring the deflection of the returned image against a scale, either visually or by means of an electronic detector. A visual autocollimator can measure angles as small as 1 arcsecond (4.85 microradians), while an electronic autocollimator can have up to 100 times more resolution.\nVisual autocollimators are often used for aligning laser rod ends and checking the face parallelism of optical windows and wedges. Electronic and digital autocollimators are used as angle measurement standards, for monitoring angular movement over long periods of time and for checking angular position repeatability in mechanical systems. Servo autocollimators are specialized compact forms of electronic autocollimators that are used in high-speed servo-feedback loops for stable-platform applications. An electronic autocollimator is typically calibrated to read the actual mirror angle.\nElectronic autocollimator.\nThe electronic autocollimator is a high precision angle measurement instrument capable of measuring angular deviations with accuracy down to fractions of an arcsecond, by electronic means only, with no optical eye-piece. \nMeasuring with an electronic autocollimator is fast, easy, accurate, and will frequently be the most cost effective procedure. Used extensively in workshops, tool rooms, inspection departments and quality control laboratories worldwide, these highly sensitive instruments will measure extremely small angular displacements, squareness, twist and parallelism.\nLaser analyzing autocollimator.\nToday, a new technology allows to improve the autocollimation instrument to allow direct measurements of incoming laser beams. This new capability opens a gate of inter-alignment between optics, mirrors and lasers.\nThis technology fusion between a century-old technology of autocollimation with recent laser technology offers a very versatile instrument capable of measurement of inter-alignment between multiple line of sights, laser in respect to mechanical datum, alignment of laser cavity, measurement of multiple rollers parallelism in roll to roll machinery, laser divergence angle and its spatial stability and many more inter-alignment applications.\nTotal station autocollimator.\nThe concept of autocollimation as an optical instrument was conceived about a century ago for non-contact measurements of angles. Hybrid technology fulfills a need recently developed by novel photonics applications has created for the alignment and measurement of optics and lasers. Implementing motorized focusing offers an additional measurement dimension by focusing on the area to be examined and performing alignment and deviations from alignment on the scale of microns. This is relevant in the adjustment phase as well as final testing and examination phases of integrated systems. Recent progress has been made in with the aim to serve the photonics AR/VR industry, involving development in interalingment, fusion of several wavelengths including NIR into one system, and measurements of multi laser array such as VCSEL in respect with other optical sensors, to improve angular accurate optical measurements to a resolution of 0.01 arcseconds.\nTypical applications.\nAn electronic autocollimator can be used in the measurement of straightness of machine components (such as guide ways) or the straightness of lines of motion of machine components. Flatness measurement, of granite surface plates, for example, can be performed by measuring straightness of multiple lines along the flat surface, then summing the deviations in line angle over the surface. Recent advancements in applications allow angular orientation measurement of wafers. This could also be done without obstructing lines of sight to the wafer's surface itself. It is applicable in wafer measuring machines and wafer processing machines. Other applications include:\nOptical measurement applications:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "182205", "revid": "1161426340", "url": "https://en.wikipedia.org/wiki?curid=182205", "title": "Forging", "text": "Forging is a manufacturing process involving the shaping of metal using localized compressive forces. The blows are delivered with a hammer (often a power hammer) or a die. Forging is often classified according to the temperature at which it is performed: cold forging (a type of cold working), warm forging, or hot forging (a type of hot working). For the latter two, the metal is heated, usually in a forge. Forged parts can range in weight from less than a kilogram to hundreds of metric tons. Forging has been done by smiths for millennia; the traditional products were kitchenware, hardware, hand tools, edged weapons, cymbals, and jewellery. Since the Industrial Revolution, forged parts are widely used in mechanisms and machines wherever a component requires high strength; such forgings usually require further processing (such as machining) to achieve a finished part. Today, forging is a major worldwide industry.\nHistory.\nForging is one of the oldest known metalworking processes. Traditionally, forging was performed by a smith using hammer and anvil, though introducing water power to the production and working of iron in the 12th century allowed the use of large trip hammers or power hammers that increased the amount and size of iron that could be produced and forged. The smithy or forge has evolved over centuries to become a facility with engineered processes, production equipment, tooling, raw materials and products to meet the demands of modern industry.\nIn modern times, industrial forging is done either with presses or with hammers powered by compressed air, electricity, hydraulics or steam. These hammers may have reciprocating weights in the thousands of pounds. Smaller power hammers, or less reciprocating weight, and hydraulic presses are common in art smithies as well. Some steam hammers remain in use, but they became obsolete with the availability of the other, more convenient, power sources.\nAdvantages and disadvantages.\nForging can produce a piece that is stronger than an equivalent cast or machined part. As the metal is shaped during the forging process, its internal grain texture deforms to follow the general shape of the part. As a result, the texture variation is continuous throughout the part, giving rise to a piece with improved strength characteristics. Additionally, forgings can achieve a lower total cost than casting or fabrication. Considering all the costs that are incurred in a product's life cycle from procurement to lead time to rework, and factoring in the costs of scrap, and downtime and other quality considerations, the long-term benefits of forgings can outweigh the short-term cost savings that castings or fabrications might offer.\nSome metals may be forged cold, but iron and steel are almost always hot forged. Hot forging prevents the work hardening that would result from cold forming, which would increase the difficulty of performing secondary machining operations on the piece. Also, while work hardening may be desirable in some circumstances, other methods of hardening the piece, such as heat treating, are generally more economical and more controllable. Alloys that are amenable to precipitation hardening, such as most aluminium alloys and titanium, can be hot forged, followed by hardening.\nProduction forging involves significant capital expenditure for machinery, tooling, facilities and personnel. In the case of hot forging, a high-temperature furnace (sometimes referred to as the forge) is required to heat ingots or billets. Owing to the size of the massive forging hammers and presses and the parts they can produce, as well as the dangers inherent in working with hot metal, a special building is frequently required to house the operation. In the case of drop forging operations, provisions must be made to absorb the shock and vibration generated by the hammer. Most forging operations use metal-forming dies, which must be precisely machined and carefully heat-treated to correctly shape the workpiece, as well as to withstand the tremendous forces involved.\nProcesses.\nThere are many different kinds of forging processes available; however, they can be grouped into three main classes:\nCommon forging processes include: roll forging, swaging, cogging, open-die forging, impression-die forging (closed die forging), press forging, cold forging, automatic hot forging and upsetting.\nTemperature.\nAll of the following forging processes can be performed at various temperatures; however, they are generally classified by whether the metal temperature is above or below the recrystallization temperature. If the temperature is above the material's recrystallization temperature it is deemed \"hot forging\"; if the temperature is below the material's recrystallization temperature but above 30% of the recrystallization temperature (on an absolute scale) it is deemed \"warm forging\"; if below 30% of the recrystallization temperature (usually room temperature) then it is deemed \"cold forging\". The main advantage of hot forging is that it can be done more quickly and precisely, and as the metal is deformed work hardening effects are negated by the recrystallization process. Cold forging typically results in work hardening of the piece.\nDrop forging.\nDrop forging is a forging process where a hammer is raised and then \"dropped\" into the workpiece to deform it according to the shape of the die. There are two types of drop forging: open-die drop forging and impression-die (or closed-die) drop forging. As the names imply, the difference is in the shape of the die, with the former not fully enclosing the workpiece, while the latter does.\nOpen-die drop forging.\nOpen-die forging is also known as \"smith forging\". In open-die forging, a hammer strikes and deforms the workpiece, which is placed on a stationary anvil. Open-die forging gets its name from the fact that the dies (the surfaces that are in contact with the workpiece) do not enclose the workpiece, allowing it to flow except where contacted by the dies. The operator therefore needs to orient and position the workpiece to get the desired shape. The dies are usually flat in shape, but some have a specially shaped surface for specialized operations. For example, a die may have a round, concave, or convex surface or be a tool to form holes or be a cut-off tool. Open-die forgings can be worked into shapes which include discs, hubs, blocks, shafts (including step shafts or with flanges), sleeves, cylinders, flats, hexes, rounds, plate, and some custom shapes. Open-die forging lends itself to short runs and is appropriate for art smithing and custom work. In some cases, open-die forging may be employed to rough-shape ingots to prepare them for subsequent operations. Open-die forging may also orient the grain to increase strength in the required direction.\nAdvantages of open-die forging\n\"\" is the successive deformation of a bar along its length using an open-die drop forge. It is commonly used to work a piece of raw material to the proper thickness. Once the proper thickness is achieved the proper width is achieved via \"edging\". \"\" is the process of concentrating material using a concave shaped open-die. The process is called \"edging\" because it is usually carried out on the ends of the workpiece. \"\" is a similar process that thins out sections of the forging using a convex shaped die. These processes prepare the workpieces for further forging processes.\nImpression-die forging.\nImpression-die forging is also called \"closed-die forging\". In impression-die forging, the metal is placed in a die resembling a mold, which is attached to an anvil. Usually, the hammer die is shaped as well. The hammer is then dropped on the workpiece, causing the metal to flow and fill the die cavities. The hammer is generally in contact with the workpiece on the scale of milliseconds. Depending on the size and complexity of the part, the hammer may be dropped multiple times in quick succession. Excess metal is squeezed out of the die cavities, forming what is referred to as \"flash\". The flash cools more rapidly than the rest of the material; this cool metal is stronger than the metal in the die, so it helps prevent more flash from forming. This also forces the metal to completely fill the die cavity. After forging, the flash is removed.\nIn commercial impression-die forging, the workpiece is usually moved through a series of cavities in a die to get from an ingot to the final form. The first impression is used to distribute the metal into the rough shape in accordance to the needs of later cavities; this impression is called an \"edging\", \"fullering\", or \"bending\" impression. The following cavities are called \"blocking\" cavities, in which the piece is working into a shape that more closely resembles the final product. These stages usually impart the workpiece with generous bends and large fillets. The final shape is forged in a \"final\" or \"finisher\" impression cavity. If there is only a short run of parts to be done, then it may be more economical for the die to lack a final impression cavity and instead machine the final features.\nImpression-die forging has been improved in recent years through increased automation which includes induction heating, mechanical feeding, positioning and manipulation, and the direct heat treatment of parts after forging. One variation of impression-die forging is called \"flashless forging\", or \"true closed-die forging\". In this type of forging, the die cavities are completely closed, which keeps the workpiece from forming flash. The major advantage to this process is that less metal is lost to flash. Flash can account for 20 to 45% of the starting material. The disadvantages of this process include additional cost due to a more complex die design and the need for better lubrication and workpiece placement.\nThere are other variations of part formation that integrate impression-die forging. One method incorporates casting a forging preform from liquid metal. The casting is removed after it has solidified, but while still hot. It is then finished in a single cavity die. The flash is trimmed, then the part is quench hardened. Another variation follows the same process as outlined above, except the preform is produced by the spraying deposition of metal droplets into shaped collectors (similar to the Osprey process).\nClosed-die forging has a high initial cost due to the creation of dies and required design work to make working die cavities. However, it has low recurring costs for each part, thus forgings become more economical with greater production volume. This is one of the major reasons closed-die forgings are often used in the automotive and tool industries. Another reason forgings are common in these industrial sectors is that forgings generally have about a 20 percent higher strength-to-weight ratio compared to cast or machined parts of the same material.\nDesign of impression-die forgings and tooling.\nForging dies are usually made of high-alloy or tool steel. Dies must be impact- and wear-resistant, maintain strength at high temperatures, and have the ability to withstand cycles of rapid heating and cooling. In order to produce a better, more economical die the following standards are maintained:\nBarrelling occurs when, due to friction between the work piece and the die or punch, the work piece bulges at its centre in such a way as to resemble a barrel. This leads to the central part of the work piece to come in contact with the sides of the die sooner than if there were no friction present, creating a much greater increase in the pressure required for the punch to finish the forging.\nThe dimensional tolerances of a steel part produced using the impression-die forging method are outlined in the table below. The dimensions across the parting plane are affected by the closure of the dies, and are therefore dependent on die wear and the thickness of the final flash. Dimensions that are completely contained within a single die segment or half can be maintained at a significantly greater level of accuracy.\nA lubricant is used when forging to reduce friction and wear. It is also used as a thermal barrier to restrict heat transfer from the workpiece to the die. Finally, the lubricant acts as a parting compound to prevent the part from sticking in the dies.\nPress forging.\nPress forging works by slowly applying a continuous pressure or force, which differs from the near-instantaneous impact of drop-hammer forging. The amount of time the dies are in contact with the workpiece is measured in seconds (as compared to the milliseconds of drop-hammer forges). The press forging operation can be done either cold or hot.\nThe main advantage of press forging, as compared to drop-hammer forging, is its ability to deform the complete workpiece. Drop-hammer forging usually only deforms the surfaces of the work piece in contact with the hammer and anvil; the interior of the workpiece will stay relatively undeformed. Another advantage to the process includes the knowledge of the new part's strain rate. By controlling the compression rate of the press forging operation, the internal strain can be controlled.\nThere are a few disadvantages to this process, most stemming from the workpiece being in contact with the dies for such an extended period of time. The operation is a time-consuming process due to the amount and length of steps. The workpiece will cool faster because the dies are in contact with workpiece; the dies facilitate drastically more heat transfer than the surrounding atmosphere. As the workpiece cools it becomes stronger and less ductile, which may induce cracking if deformation continues. Therefore, heated dies are usually used to reduce heat loss, promote surface flow, and enable the production of finer details and closer tolerances. The workpiece may also need to be reheated.\nWhen done in high productivity, press forging is more economical than hammer forging. The operation also creates closer tolerances. In hammer forging a lot of the work is absorbed by the machinery; when in press forging, the greater percentage of work is used in the work piece. Another advantage is that the operation can be used to create any size part because there is no limit to the size of the press forging machine. New press forging techniques have been able to create a higher degree of mechanical and orientation integrity. By the constraint of oxidation to the outer layers of the part, reduced levels of microcracking occur in the finished part.\nPress forging can be used to perform all types of forging, including open-die and impression-die forging. Impression-die press forging usually requires less draft than drop forging and has better dimensional accuracy. Also, press forgings can often be done in one closing of the dies, allowing for easy automation.\nUpset forging.\nUpset forging increases the diameter of the workpiece by compressing its length. Based on number of pieces produced, this is the most widely used forging process. A few examples of common parts produced using the upset forging process are engine valves, couplings, bolts, screws, and other fasteners.\nUpset forging is usually done in special high-speed machines called \"crank presses\". The machines are usually set up to work in the horizontal plane, to facilitate the quick exchange of workpieces from one station to the next, but upsetting can also be done in a vertical crank press or a hydraulic press. The initial workpiece is usually wire or rod, but some machines can accept bars up to in diameter and a capacity of over 1000 tons. The standard upsetting machine employs split dies that contain multiple cavities. The dies open enough to allow the workpiece to move from one cavity to the next; the dies then close and the heading tool, or ram, then moves longitudinally against the bar, upsetting it into the cavity. If all of the cavities are utilized on every cycle, then a finished part will be produced with every cycle, which makes this process advantageous for mass production.\nThese rules must be followed when designing parts to be upset forged:\nAutomatic hot forging.\nThe automatic hot forging process involves feeding mill-length steel bars (typically long) into one end of the machine at room temperature and hot forged products emerge from the other end. This all occurs rapidly; small parts can be made at a rate of 180 parts per minute (ppm) and larger can be made at a rate of 90 ppm. The parts can be solid or hollow, round or symmetrical, up to , and up to in diameter. The main advantages to this process are its high output rate and ability to accept low-cost materials. Little labor is required to operate the machinery.\nThere is no flash produced so material savings are between 20 and 30% over conventional forging. The final product is a consistent so air cooling will result in a part that is still easily machinable (the advantage being the lack of annealing required after forging). Tolerances are usually ±, surfaces are clean, and draft angles are 0.5 to 1°. Tool life is nearly double that of conventional forging because contact times are on the order of 0.06-second. The downside is that this process is only feasible on smaller symmetric parts and cost; the initial investment can be over $10 million, so large quantities are required to justify this process.\nThe process starts by heating the bar to in less than 60 seconds using high-power induction coils. It is then descaled with rollers, sheared into blanks, and transferred through several successive forming stages, during which it is upset, preformed, final forged, and pierced (if necessary). This process can also be coupled with high-speed cold-forming operations. Generally, the cold forming operation will do the finishing stage so that the advantages of cold-working can be obtained, while maintaining the high speed of automatic hot forging.\nExamples of parts made by this process are: wheel hub unit bearings, transmission gears, tapered roller bearing races, stainless steel coupling flanges, and neck rings for liquid propane (LP) gas cylinders. Manual transmission gears are an example of automatic hot forging used in conjunction with cold working.\nRoll forging.\nRoll forging is a process where round or flat bar stock is reduced in thickness and increased in length. Roll forging is performed using two cylindrical or semi-cylindrical rolls, each containing one or more shaped grooves. A heated bar is inserted into the rolls and when it hits a spot the rolls rotate and the bar is progressively shaped as it is rolled through the machine. The piece is then transferred to the next set of grooves or turned around and reinserted into the same grooves. This continues until the desired shape and size is achieved. The advantage of this process is there is no flash and it imparts a favorable grain structure into the workpiece.\nExamples of products produced using this method include axles, tapered levers and leaf springs.\nNet-shape and near-net-shape forging.\nThis process is also known as \"precision forging\". It was developed to minimize cost and waste associated with post-forging operations. Therefore, the final product from a precision forging needs little or no final machining. Cost savings are gained from the use of less material, and thus less scrap, the overall decrease in energy used, and the reduction or elimination of machining. Precision forging also requires less of a draft, 1° to 0°. The downside of this process is its cost, therefore it is only implemented if significant cost reduction can be achieved.\nCold forging.\nNear net shape forging is most common when parts are forged without heating the slug, bar or billet. Aluminum is a common material that can be cold forged depending on final shape. Lubrication of the parts being formed is critical to increase the life of the mating dies.\nInduction forging.\nUnlike the above processes, induction forging is based on the type of heating style used. Many of the above processes can be used in conjunction with this heating method.\nMultidirectional forging.\nMultidirectional forging is forming of a work piece in a single step in several directions. The multidirectional forming takes place through constructive measures of the tool. The vertical movement of the press ram is redirected using wedges which distributes and redirects the force of the forging press in horizontal directions.\nIsothermal forging.\nIsothermal forging is a process by which the materials and the die are heated to the same temperature (\"iso-\" meaning \"equal\"). Adiabatic heating is used to assist in the deformation of the material, meaning the strain rates are highly controlled. This technique is commonly used for forging aluminium, which has a lower forging temperature than steels. Forging temperatures for aluminum are around , while steels and super alloys can be .\nBenefits:\nDisadvantages:\nMaterials and applications.\nForging of steel.\nDepending on the forming temperature steel forging can be divided into:\nFor industrial processes steel alloys are primarily forged in hot condition. Brass, bronze, copper, precious metals and their alloys are manufactured by cold forging processes; each metal requires a different forging temperature.\nForging of aluminium.\nDue to the narrow temperature range and high thermal conductivity, aluminium forging can only be realized in a particular process window. To provide good forming conditions a homogeneous temperature distribution in the entire workpiece is necessary. Therefore, the control of the tool temperature has a major influence to the process. For example, by optimizing the preform geometries the local effective strains can be influenced to reduce local overheating for a more homogeneous temperature distribution.\nApplication of aluminium forged parts.\nHigh-strength aluminium alloys have the tensile strength of medium strong steel alloys while providing significant weight advantages. Therefore, aluminium forged parts are mainly used in aerospace, automotive industry and many other fields of engineering especially in those fields, where highest safety standards against failure by abuse, by shock or vibratory stresses are needed. Such parts are for example pistons, chassis parts, steering components and brake parts. Commonly used alloys are AlSi1MgMn (EN AW-6082) and AlZnMgCu1,5 (EN AW-7075). About 80% of all aluminium forged parts are made of AlSi1MgMn. The high-strength alloy AlZnMgCu1,5 is mainly used for aerospace applications.\nForging of magnesium.\nMagnesium alloys are more difficult to forge due to their low plasticity, low sensitivity to strain rates and narrow forming temperature. Using semi-open die hot forging with a three-slide forging press (TSFP) has become a newly developed forging method for Mg-Al alloy AZ31, commonly used in forming aircraft brackets. This forging method has shown to improve tensile properties but lacks uniform grain size. Even though the application of magnesium alloys increases by 15–20% each year in the aerospace and automotive industry, forging magnesium alloys with specialized dies is expensive and an unfeasible method to produce parts for a mass market. Instead, most magnesium alloy parts for industry are produced by casting methods.\nEquipment.\nThe most common type of forging equipment is the hammer and anvil. Principles behind the hammer and anvil are still used today in \"drop-hammer\" equipment. The principle behind the machine is simple: raise the hammer and drop it or propel it into the workpiece, which rests on the anvil. The main variations between drop-hammers are in the way the hammer is powered; the most common being air and steam hammers. Drop-hammers usually operate in a vertical position. The main reason for this is excess energy (energy that is not used to deform the workpiece) that is not released as heat or sound needs to be transmitted to the foundation. Moreover, a large machine base is needed to absorb the impacts.\nTo overcome some shortcomings of the drop-hammer, the \"counterblow machine\" or \"impactor\" is used. In a counterblow machine both the hammer and anvil move and the workpiece is held between them. Here excess energy becomes recoil. This allows the machine to work horizontally and have a smaller base. Other advantages include less noise, heat and vibration. It also produces a distinctly different flow pattern. Both of these machines can be used for open-die or closed-die forging.\nForging presses.\nA \"forging press\", often just called a press, is used for press forging. There are two main types: mechanical and hydraulic presses. Mechanical presses function by using cams, cranks and/or toggles to produce a preset (a predetermined force at a certain location in the stroke) and reproducible stroke. Due to the nature of this type of system, different forces are available at different stroke positions. Mechanical presses are faster than their hydraulic counterparts (up to 50 strokes per minute). Their capacities range from 3 to 160 MN (300 to 18,000 short tons-force). Hydraulic presses use fluid pressure and a piston to generate force. The advantages of a hydraulic press over a mechanical press are its flexibility and greater capacity. The disadvantages include a slower, larger, and costlier machine to operate.\nThe roll forging, upsetting, and automatic hot forging processes all use specialized machinery.", "Engineering,_Manufacturing": 1.000002861, "qwen": "Yes"}
{"id": "21658478", "revid": "1154887345", "url": "https://en.wikipedia.org/wiki?curid=21658478", "title": "Bourns, Inc.", "text": "Bourns, Inc. is an American electronics company that develops, manufactures and supplies electronic components for a variety of industries including automotive, industrial, instrumentation, medical electronics, consumer equipment and portable electronics.\nEstablished in Altadena, California in 1947 by Marlan and Rosemary Bourns, graduates of the University of Michigan, the company was founded to develop and sell electronic components and sensors to the aerospace industry.\nBourns has 15 manufacturing facilities around the world and has continued growing through the development of new products and technologies as well as through acquisitions. The company has approximately 9000 employees worldwide.\nIts current Chairman of the Board and CEO is Gordon Bourns, the son of the co-founders.\nHistory.\nMarlan and Rosemary Bourns started the company in their garage in Altadena, California in 1947. Their invention of linear motion and vane position potentiometers provided a method of accurately determining an aircraft's pitch, and helped to grow their business into a global corporation.\nHeadquartered in Riverside, California, Bourns makes and provides a broad range of electronic components and circuit protection devices including automotive sensors, circuit protection solutions, magnetic and inductor products, specialty engineering and manufacturing services, precision potentiometers, panel controls, encoders and resistive products.\nTechnology innovations.\nIn 1952, Bourns patented the trimming potentiometer, trademarked \"Trimpot\". In 1995, Bourns acquired VRN's Trimmer assets and introduced the first 4 mm surface-mount sealed tact switch. In 2008, Bourns acquired the Transient Blocking Unit (TBU) assets of Fultec Semiconductor, Inc.", "Engineering,_Manufacturing": 0.9999781847, "qwen": "Yes"}
{"id": "40219482", "revid": "25959191", "url": "https://en.wikipedia.org/wiki?curid=40219482", "title": "Future Supply Chains", "text": "Future Supply Chain Solutions Ltd. (FSC) is an Indian supply chain and logistics company.\nFSC caters to corporates in Food & FMCG; Apparels, Footwear & Accessories; Home and Furniture, Consumer Electronics & Hi- Tech; Automotive; Pharma and Light Engineering domain.\nHistory.\nFuture Supply Chain Solutions Ltd. (FSC) was incorporated in March, 2006.", "Engineering,_Manufacturing": 0.9999945164, "qwen": "Yes"}
{"id": "21235839", "revid": "1148597708", "url": "https://en.wikipedia.org/wiki?curid=21235839", "title": "Cemented carbide", "text": "Cemented carbides are a class of hard materials used extensively for cutting tools, as well as in other industrial applications. It consists of fine particles of carbide cemented into a composite by a binder metal. Cemented carbides commonly use tungsten carbide (WC), titanium carbide (TiC), or tantalum carbide (TaC) as the aggregate. Mentions of \"carbide\" or \"tungsten carbide\" in industrial contexts usually refer to these cemented composites.\nMost of the time, carbide cutters will leave a better surface finish on a part and allow for faster machining than high-speed steel or other tool steels. Carbide tools can withstand higher temperatures at the cutter-workpiece interface than standard high-speed steel tools (which is a principal reason enabling the faster machining). Carbide is usually superior for the cutting of tough materials such as carbon steel or stainless steel, as well as in situations where other cutting tools would wear away faster, such as high-quantity production runs. In situations where carbide tooling is not required, high-speed steel is preferred for its lower cost.\nConstruction.\nCemented carbides are metal matrix composites where carbide particles act as the aggregate and a metallic binder serves as the matrix (analogous to concrete, where a gravel aggregate is suspended in a cement matrix). The structure of cemented carbide is conceptually similar to that of a grinding wheel, but the abrasive particles are much smaller; macroscopically, the material of a carbide cutter appears homogeneous.\nThe process of combining the carbide particles with the binder is referred to as sintering or hot isostatic pressing (HIP). During this process, the material is heated until the binder enters a liquid phase while the carbide grains (which have a much higher melting point) remain solid. At this elevated temperature and pressure, the carbide grains rearrange themselves and compact together, forming a porous matrix. The ductility of the metal binder serves to offset the brittleness of the carbide ceramic, resulting in the composite's high overall toughness and durability. By controlling various parameters, including grain size, cobalt content, dotation (e.g., alloy carbides) codice_1 and carbon content, a carbide manufacturer can tailor the carbide's performance to specific applications.\nThe first cemented carbide developed was tungsten carbide (introduced in 1927) which uses tungsten carbide particles held together by a cobalt metal binder. Since then, other cemented carbides have been developed, such as titanium carbide, which is better suited for cutting steel, and tantalum carbide, which is tougher than tungsten carbide.\nPhysical propertiescodice_1.\nThe coefficient of thermal expansion of cemented tungsten carbide is found to vary with the amount of cobalt used as a metal binder. For 5.9% cobalt samples, a coefficient of 4.4 µm·m−1·K−1 was measured, whereas 13% cobalt samples have a coefficient of around 5.0 µm·m−1·K−1. Both values are only valid from to due to non-linearity in the thermal expansion process.\nApplications.\nInserts for metal cutting.\nCarbide is more expensive per unit than other typical tool materials, and it is more brittle, making it susceptible to chipping and breaking. To offset these problems, the carbide cutting tip itself is often in the form of a small insert for a larger tipped tool whose shank is made of another material, usually carbon tool steel. This gives the benefit of using carbide at the cutting interface without the high cost and brittleness of making the entire tool out of carbide. Most modern face mills use carbide inserts, as well as many lathe tools and endmills. In recent decades, though, solid-carbide endmills have also become more commonly used, wherever the application's characteristics make the pros (such as shorter cycle times) outweigh the cons (mentioned above). As well, modern turning (lathe) tooling may use a carbide insert on a carbide tool such as a boring bar, which are more rigid than steel insert holders and therefor less prone to vibration, which is of particular importance with boring or threading bars that may need to reach into a part to a depth many times the tool diameter.\nInsert coatings.\nTo increase the life of carbide tools, they are sometimes coated. Five such coatings are TiN (titanium nitride), TiC (titanium carbide), Ti(C)N (titanium carbide-nitride), TiAlN (titanium aluminium nitride) and AlTiN (aluminium titanium nitride). (Newer coatings, known as DLC (diamond-like carbon) are beginning to surface, enabling the cutting power of diamond without the unwanted chemical reaction between real diamond and iron.) Most coatings generally increase a tool's hardness and/or lubricity. A coating allows the cutting edge of a tool to cleanly pass through the material without having the material gall (stick) to it. The coating also helps to decrease the temperature associated with the cutting process and increase the life of the tool. The coating is usually deposited via thermal chemical vapor deposition (CVD) and, for certain applications, with the mechanical physical vapor deposition (PVD) method. However, if the deposition is performed at too high temperature, an \"eta phase\" of a Co6W6C tertiary carbide forms at the interface between the carbide and the cobalt phase, which may lead to adhesion failure of the coating.\nInserts for mining tools.\nMining and tunneling cutting tools are most often fitted with cemented carbide tips, the so-called \"button bits\". Artificial diamond can replace the cemented carbide buttons only when conditions are ideal, but as rock drilling is a tough job cemented carbide button bits remain the most used type throughout the world.\nRolls for hot-roll and cold-roll applications.\nSince the mid-1960s, steel mills around the world have applied cemented carbide to the rolls of their rolling mills for both hot and cold rolling of tubes, bars, and flats.\nOther industrial applications.\nThis category contains a countless number of applications, but can be split into three main areas:\nSome key areas where cemented carbide components are used:\nNon-industrial uses.\nJewellery.\nTungsten carbide has become a popular material in the bridal jewellery industry, due to its extreme hardness and high resistance to scratching. Given its brittleness, it is prone to chip, crack, or shatter in jewellery applications. Once fractured, it cannot be repaired.\nHistory.\nThe initial development of cemented and sintered carbides occurred in Germany in the 1920s. ThyssenKrupp says [in historical present tense], \"Sintered tungsten carbide was developed by the 'Osram study society for electrical lighting' to replace diamonds as a material for machining metal. Not having the equipment to exploit this material on an industrial scale, Osram sells the license to Krupp at the end of 1925. In 1926 Krupp brings sintered carbide onto the market under the name WIDIA (acronym for = like diamond).\" Machinery's Handbook gives the date of carbide tools' commercial introduction as 1927. Burghardt and Axelrod give the date of their commercial introduction in the United States as 1928. Subsequent development occurred in various countries.\nAlthough the marketing pitch was slightly hyperbolic (carbides being not entirely equal to diamond), carbide tooling offered an improvement in cutting speeds and feeds so remarkable that, like high-speed steel had done two decades earlier, it forced machine tool designers to rethink every aspect of existing designs, with an eye toward yet more rigidity and yet better spindle bearings.\nDuring World War II there was a tungsten shortage in Germany. It was found that tungsten in carbide cuts metal more efficiently than tungsten in high-speed steel, so to economise on the use of tungsten, carbides were used for metal cutting as much as possible.\nThe name became a genericized trademark in various countries and languages, including English (widia, ), although the genericized sense was never especially widespread in English (\"carbide\" is the normal generic term). Since 2009, the name has been revived as a brand name by Kennametal, and the brand subsumes numerous popular brands of cutting tools.\nUncoated tips brazed to their shanks were the first form. Clamped indexable inserts and today's wide variety of coatings are advances made in the decades since. With every passing decade, the use of carbide has become less \"special\" and more ubiquitous.\nRegarding fine-grained hardmetal, an attempt has been made to follow the scientific and technological steps associated with its production; this task is not easy, though, because of the restrictions placed by commercial, and in some cases research, organisations, in not publicising relevant information until long after the date of the initial work. Thus, placing data in an historical, chronological order is somewhat difficult. However, it has been possible to establish that as far back as 1929, approximately 6 years after the first patent was granted, Krupp/Osram workers had identified the positive aspects of tungsten carbide grain refinement. By 1939, they had also discovered the beneficial effects of adding a small amount of vanadium and tantalum carbide. This effectively controlled discontinuous grain growth.\nWhat was considered 'fine' in one decade was considered not so fine in the next. Thus, a grain size in the range 0.5–3.0 μm was considered fine in the early years, but by the 1990s, the era of the nano-crystalline material had arrived, with a grain size of 20–50 nm.\nPobedit.\n\"Pobedit\"  is a sintered carbide alloy of about 90% tungsten carbide as a hard phase, and about 10% cobalt (Co) as a binder phase, with a small amount of additional carbon. It was developed in the Soviet Union in 1929, it is described as a material from which cutting tools are made. Later a number of similar alloys based on tungsten and cobalt were developed, and the name of 'pobedit' was retained for them as well.\nPobedit is usually produced by powder metallurgy in the form of plates of different shapes and sizes. The manufacturing process is as follows: a fine powder of tungsten carbide (or other refractory carbide) and a fine powder of binder material such as cobalt or nickel both get intermixed and then pressed into the appropriate forms. Pressed plates are sintered at a temperature close to the melting point of the binder metal, which yields a very tight and solid substance.\nThe plates of this superhard composite are applied to manufacturing of metal-cutting and drilling tools; they are usually soldered on the cutting tool tips. Heat post-treatment is not required. The pobedit inserts at the tips of drill bits are still very widespread in Russia.", "Engineering,_Manufacturing": 0.9999958277, "qwen": "Yes"}
{"id": "3283459", "revid": "20398877", "url": "https://en.wikipedia.org/wiki?curid=3283459", "title": "Die cutting (web)", "text": "Die cutting is the general process of using a die to shear webs of low-strength materials, such as rubber, fibre, foil, cloth, paper, corrugated fibreboard, chipboard, paperboard, plastics, pressure-sensitive adhesive tapes, foam, and sheet metal. In the metalworking and leather industries, the process is known as clicking and the machine may be referred to as a \"clicking machine\". When a \"dinking die\" or \"dinking machine\" is used, the process is known as dinking. Commonly produced items using this process include gaskets, labels, tokens, corrugated boxes, and envelopes.\nDie cutting started as a process of cutting leather for the shoe industry in the mid-19th century. It is now sophisticated enough to cut through just one layer of a laminate, so it is now used on labels, postage stamps, and other stickers; this type of die cutting is known as \"\".\nDie cutting can be done on either flatbed or rotary presses. Rotary die cutting is often done inline with printing. The primary difference between rotary die cutting and flatbed die cutting is that the flatbed is not as fast but the tools are cheaper. This process lends itself to smaller production runs where it is not as easy to absorb the added cost of a rotary die.\nRotary die cutting.\nRotary die cutting is die cutting using a cylindrical die on a rotary press and may be known as a rotary die cutter or RDC. A long sheet or web of material will be fed through the press into an area known as a \"station\" which holds a rotary tool that will cut out shapes, make perforations or creases, or even cut the sheet or web into smaller parts. A series of gears will force the die to rotate at the same speed as the rest of the press, ensuring that any cuts the die makes line up with the printing on the material. The machines used for this process can incorporate multiple \"stations\" that die cut a particular shape in the material. In each of these stations lie one or more of these geared tools or printing cylinders, and some machines use automatic eye registration to make sure the cuts and/or printing are lined up with one another when lower tolerances are required.\nDies used in rotary die cutting are either solid engraved dies, adjustable dies, or magnetic plate tooling. Engraved dies have a much higher tolerance and are machined out of a solid steel bar normally made out of tool steel. Adjustable dies have removable blades that can be easily replaced with other blades, either due to wear or to cut a different material, while magnetic plate tooling has a cylinder that has magnets placed in it, and an engraved metal plate is attached or wrapped around the base cylinder holding onto it by the force of the magnets.\nDinking.\nDinking is a manufacturing process. Dinking uses special dies called dinking dies, which are hollow cutters. The edges of the dies are usually beveled about 20° and sharpened. The material is punched through into a wood or soft metal block in order to not dull the edges. The die may be pressed into the material with a hammer or a mechanical press.", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "3284517", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=3284517", "title": "Productive efficiency", "text": "In microeconomic theory, productive efficiency (or production efficiency) is a situation in which the economy or an economic system (e.g., bank, hospital, industry, country) operating within the constraints of current industrial technology cannot increase production of one good without sacrificing production of another good. In simple terms, the concept is illustrated on a production possibility frontier (PPF), where all points on the curve are points of productive efficiency. An equilibrium may be productively efficient without being allocatively efficient — i.e. it may result in a distribution of goods where social welfare is not maximized (bearing in mind that social welfare is a nebulous objective function subject to political controversy). \nProductive efficiency is an aspect of economic efficiency that focuses on how to maximize output of a chosen product portfolio, without concern for whether your product portfolio is making goods in the right proportion; in misguided application, it will aid in manufacturing the wrong basket of outputs faster and cheaper than ever before. \nProductive efficiency of an industry requires that all firms operate using best-practice technological and managerial processes and that there is no further reallocation that bring more output with the same inputs and the same production technology. By improving these processes, an economy or business can extend its production possibility frontier outward, so that efficient production yields more output than previously.\nProductive inefficiency, with the economy operating below its production possibilities frontier, can occur because the productive inputs physical capital and labor are underutilized—that is, some capital or labor is left sitting idle—or because these inputs are allocated in inappropriate combinations to the different industries that use them.\nIn long-run equilibrium for perfectly competitive markets, productive efficiency occurs at the base of the average total cost curve — i.e. where marginal cost equals average total cost — for each good.\nDue to the nature and culture of monopolistic companies, they may not be productively efficient because of X-inefficiency, whereby companies operating in a monopoly have less of an incentive to maximize output due to lack of competition. However, due to economies of scale it can be possible for the profit-maximizing level of output of monopolistic companies to occur with a lower price to the consumer than perfectly competitive companies.\nTheoretical measures.\nMany theoretical measures of production efficiency have been proposed in the literature as well as many approaches to estimate them. \nThe most popular measures of efficiency include Farrell measure (also known as Debreu–Farrell measure, since Debreu (1951) has similar ideas). This measure is also the reciprocal of the Shephard's distance function. These can be defined with either the input orientation (fix outputs and measure maximal possible reduction in inputs) or the output orientation (fix inputs and measure maximal possible expansion in outputs). \nA generalisation of these is the so-called directional distance function, where one can select any direction (or orientation) for measuring the production efficiency. \nThe most popular for estimating production efficiency are data envelopment analysis and stochastic frontier analysis. \nSee the recent book by Sickles and Zelenyuk (2019) for comprehensive coverage of the theory and related estimation and many references therein.", "Engineering,_Manufacturing": 0.9999120235, "qwen": "Yes"}
{"id": "44079782", "revid": "4173550", "url": "https://en.wikipedia.org/wiki?curid=44079782", "title": "Packaging machinery", "text": "Packaging machinery is used throughout all packaging operations, involving primary packages to distribution packs. This includes many packaging processes: fabrication, cleaning, filling, sealing, combining, labeling, overwrapping, palletizing.\nOverview.\nSome packaging operations cannot be accomplished without packaging equipment. For example many packages include heat seals to prepare or seal a package. Heat sealers are needed, even in slow labor-intensive operations.\nWith many industries, the effectiveness of the heat seal is critical to product safety so the heat sealing operation must closely controlled with documented Verification and validation protocols. Food, drug, and medical regulations require consistent seals on packages. Proper equipment is needed.\nAutomation.\nPackaging operations can be designed for variable package sizes and forms or for handling only uniform packages, where the machinery or packaging line is adjustable between production runs. Certainly slow manual operations allow workers to be flexible to package variation but also some automated lines can handle significant random variation.\nMoving from manual operations, through semi-automatic operations to fully automated packaging lines offers advantages to some packagers. Other than the obvious control of labor costs, quality can be more consistent, and throughput can be optimized.\nEfforts at packaging line automation increasingly use programmable logic controllers and robotics.\nLarge fully automatic packaging lines can involve several pieces of major equipment from different manufactures as well as conveyors and ancillary equipment. Integrating such systems can be a challenge. Often consultants or external engineering firms are used to coordinate large projects.\nChoosing packaging machinery.\nChoosing packaging machinery includes an assessment of technical capabilities, labor requirements, worker safety, maintainability, serviceability, reliability, ability to integrate into the packaging line, capital cost, floorspace, flexibility (change-over, materials, multiple products, etc.), energy requirements, quality of outgoing packages, qualifications (for food, pharmaceuticals, etc.), throughput, efficiency, productivity, ergonomics, return on investment, etc.\nPackaging machinery can be:\nIn addition to purchasing equipment, leasing options are often attractive.\nMachinery must be compatible with the expected operating conditions. For example, cold temperature operations require special considerations. Some industries must perform periodic washdowns of all equipment. This high pressure chemical washing puts special demands on machinery and control systems. Condensation within closed portions of machinery can also be problematic.\nMachinery needs to keep control of the product being packaged. For example, powders need to be stable, liquids cannot slosh out, etc.\nSome manufacturers decide not to do their own packaging but to employ contract packagers to perform all or some operations. Capital, labor, and other costs are outsourced.\nTypes of machinery.\nPackaging machines may be of the following general types:\nFunction.\nPackaging is necessary to protect products, and is now done mainly through the use of packaging machinery. Machinery plays increasingly important roles such as: ", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "7008837", "revid": "1162316243", "url": "https://en.wikipedia.org/wiki?curid=7008837", "title": "Jig borer", "text": "The jig borer is a type of machine tool invented at the end of World War I to enable the quick and precise location of hole centers. It was invented independently in Switzerland and the United States. It resembles a specialized kind of milling machine that provides tool and die makers with a higher degree of positioning precision (repeatability) and accuracy than those provided by general machines. Although capable of light milling, a jig borer is more suited to highly accurate drilling, boring, and reaming, where the quill or headstock does not see the significant side loading that it would with mill work. The result is a machine designed more for location accuracy than heavy material removal.\nA typical jig borer has a work table of around which can be moved using large handwheels (with micrometer-style readouts and verniers) on particularly carefully made shafts with a strong degree of gearing; this allows positions to be set on the two axes to an accuracy of . It is generally used to enlarge to a precise size smaller holes drilled with less accurate machinery in approximately the correct place (ie with the small hole strictly within the area to be bored out for the large hole).\nJig borers are limited to working materials that are still soft enough to be bored. Often a jig is hardened; for a jig borer this requires the material to be bored first and then hardened, which may introduce distortion. Consequently the jig grinder was developed as a machine with the precision of the jig borer, but capable of working materials in their hardened state.\nHistory.\nBefore the jig borer was developed, hole center location had been accomplished either with layout (either quickly-but-imprecisely or painstakingly-and-precisely) or with drill jigs (themselves made with painstaking-and-precise layout). The jig borer was invented to expedite the making of drill jigs, but it helped to eliminate the need for drill jigs entirely by making quick precision directly available for the parts that the jigs would have been created for. The revolutionary underlying principle was that advances in machine tool control that expedited the making of jigs were fundamentally a way to expedite the cutting process itself, for which the jig was just a means to an end. Thus the jig borer's development helped advance machine tool technology toward later NC and CNC development. The jig borer was a logical extension of manual machine tool technology that began to incorporate some then-novel concepts that would become routine with NC and CNC control, such as:\nFranklin D. Jones, in his textbook \"Machine Shop Training Course\" (5th ed), noted:\nSeveral innovations in the development of the jig borer were the work of the Moore Special Tool Company. In particular, the adoption of hardened and accurate leadscrews, formed by grinding, rather than a soft leadscrew with a compensating nut.\nThe technological advances that led to the jig borer and NC were about to usher in the age of CNC and CAD/CAM, radically changing the way people manufacture many of their goods.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "7010487", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=7010487", "title": "Diamond blade", "text": "A diamond blade is a saw blade which has diamonds fixed on its edge for cutting hard or abrasive materials. There are many types of diamond blade, and they have many uses, including cutting stone, concrete, asphalt, bricks, coal balls, glass, and ceramics in the construction industry; cutting semiconductor materials in the semiconductor industry; and cutting gemstones, including diamonds, in the gem industry.\nTypes.\nDiamond blades are available in different shapes:\nDiamond blades designed for specific uses include marble, granite, concrete, asphalt, masonry, and gem-cutting blades. General purpose blades are also available.\nManufacturing methods.\nElectroplating.\nBlades using diamonds embedded in a metal coating, typically of nickel electroplated onto a steel blade base, can be made to be very thin—blades can be tens of micrometres thick, for use in precise cuttings.\nVacuum brazing.\nVacuum brazed diamond saw blades are manufactured by brazing synthetic diamond particles to the outside edge of the circular saw blade in a vacuum brazing furnace. All of the diamond particles are fully exposed and fastened on the exterior cutting edge of the blade instead of being embedded within a metal-diamond mixture. Depending on the manufacturer's recommended blade application, vacuum brazed blades will cut a wide variety of material including concrete, masonry, steel, various irons, plastic, tile, wood and glass.\nFiner synthetic diamond grits will reduce the chipping of tile and burring of steel and provide a smoother finish. Larger diamond grits will provide a higher cutting speed, but will be more likely to cause chipping, burring, or cracking. Fire departments sometimes use vacuum brazed saw blades and require blades to be made with a very large diamond grit, to tear through material quickly. An intermediate grit size is used by the production industry.\nSintering.\nSintered metal-bonded diamond blades are the most common type of blade. These blades consist of a steel core (the base is steel plate, unlike that of the wires used in diamond wire saws) and \"diamond segments\", which are made by combining synthetic diamond crystals with metal powder and then sintering them. The diamond segments are also known as the \"cutting teeth\" of the blade.\nThe steel core can vary in design. Some cores have spaces (known as gullets) between segments to provide cooling and slurry removal, while others have a single continuous rim for smoother cutting. The type of core that can be used depends on the type of materials that the diamond blade is designed to cut.\nGenerally, there are three types of sintered metal-bonded diamond blades according to their manufacturing methods: wholly sintered diamond blades, silver brazed diamond blades and laser welded diamond blades.\nA wholly sintered diamond blade is made by putting the steel core, together with the diamonds and the metal bond materials, into a mold and then sintering it in a sintering furnace equipment. Consequently, the diameter of wholly sintered diamond blades is not very large, normally not more than . Because it is participating in the sintering process, the steel core cannot be quenched, so the hardness and strength of the core are not very high. This means that these types of diamond blade may deform in high-load and high-intensity cutting processes and can exhibit low cutting efficiency.\nSilver brazed and laser welded diamond blades do not have this weakness because their diamond segments and steel core are treated separately. The steel core can be quenched and processed with other heat treatments, so its hardness and strength can be high, meaning that the blade can be used in high-load and high-intensity cutting processes with high cutting efficiency and a smaller degree of deformation.\nSilver brazed diamond blades' diamond segments are brazed to the steel core using a silver solder. These blades can only be used in wet cuttings. If they are used in dry cuttings, the silver solder may melt and the segments can break from the steel core and become a serious safety hazard. A laser melts and combines the metal of the diamond segment and the steel core creating a stronger weld, which can hold the segments even in high temperatures, meaning that laser welded diamond blades can be used to cut many types of stone without water cooling. However, when cutting very hard or abrasive materials, e.g., concrete containing reinforcing rebar, laser welded diamond blades should also be used with adequate water. Otherwise, it is possible for the diamond segment itself to break or the steel core below the segment to wear and break, creating serious safety hazards.\nApplication of sintered metal-bonded diamond blades.\nA diamond blade grinds, rather than cuts, through material. Blades typically have rectangular teeth (segments) which contain diamond crystals embedded throughout the segment for grinding through very hard materials.\nThe \"bond\" is a term used for the softness or hardness of the powder metal being used to form the segments. The powdered metals hold the diamonds in place. The bond controls the rate at which the diamond segments wear down allowing new diamonds to become exposed at the surface to continue grinding with a \"sharp\" edge. An important step in choosing a blade is to match the bond to the specific material to be cut. Additional factors to consider are the type and power of the equipment to be used and the availability of water. Harder materials need a softer bonded segment to allow for continuous diamond exposure. Softer materials like asphalt or freshly poured concrete can use a harder segment to resist the increased wear that softer, abrasive materials create. In addition, the diamonds' grit (size), toughness, and concentration should also match the nature of the material to be sawed. For example, when hard materials are cut, the diamonds should be smaller.\nThere are other factors that should be considered when choosing a diamond blade for a particular application. These include the type (manufacturing method) of the blade, the availability of water in the cutting process, the horsepower of the saw, and the acceptable level of noise created by the saw. For example, if the horsepower of a saw machine is large, the diamond concentration of the diamond blade should be higher, or the bond should be harder. Higher diamond concentration will decrease the impact on each single diamond in working, while a harder bond will hold the diamonds more firmly.\nCutting with or without water.\nMany blades are designed to operate either wet or dry. However, diamond tools and blades work better when wet, and dry cutting should be limited to situations in which water cannot or should not be used. Water will prevent the blade from overheating, greatly reduce the amount of harmful dust created by cutting, remove the slurry from the cut, and extend the life of the blade, since diamond is unable to withstand the forces involved at the elevated temperatures involved in dry cutting ceramic and abrasive materials, and will be subject to rapid tool wear and possible failure.\nWhen water cannot be used (in, for example, electrical saws), measures should be taken to ensure that the operator does not inhale the dust created by the process, which can cause silicosis, a serious lung disease. When dry cutting, the blade should be allowed to cool off periodically. Cooling can be increased by allowing the blade to spin freely out of the cut. The OSHA has strict regulations regarding silica dust and requires a N95 NIOSH-approved respirator in work sites where dangerous amounts of silica dust are present.\nReferences.\nSources.\n\n", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "1830354", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=1830354", "title": "Heat-affected zone", "text": "In fusion welding, the heat-affected zone (HAZ) is the area of base material, either a metal or a thermoplastic, which is not melted but has had its microstructure and properties altered by welding or heat intensive cutting operations. The heat from the welding process and subsequent re-cooling causes this change from the weld interface to the termination of the sensitizing temperature in the base metal. The extent and magnitude of property change depends primarily on the base material, the weld filler metal, and the amount and concentration of heat input by the welding process.\nThe thermal diffusivity of the base material plays a large role—if the diffusivity is high, the material cooling rate is high and the HAZ is relatively small. Alternatively, a low diffusivity leads to slower cooling and a larger HAZ. The amount of heat input during the welding process also plays an important role as well, as processes like oxyfuel welding use high heat input and increase the size of the HAZ. Processes like laser beam welding and electron beam welding give a highly concentrated, limited amount of heat, resulting in a small HAZ. Arc welding falls between these two extremes, with the individual processes varying somewhat in heat input. To calculate the heat input for arc welding procedures, the following formula is used:\nwhere = heat input (kJ/mm), = voltage (V), = current (A), and = welding speed (mm/min). The efficiency is dependent on the welding process used, with gas tungsten arc welding having a value of 0.6, shielded metal arc welding and gas metal arc welding having a value of 0.8, and submerged arc welding 1.0.", "Engineering,_Manufacturing": 0.9963489771, "qwen": "Yes"}
{"id": "73575144", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=73575144", "title": "Power Surfacing", "text": "Power Surfacing is a computer-aided design software that allows users to create and edit complex freeform surfaces in SOLIDWORKS. It is developed by nPower Software, a division of IntegrityWare Inc., and is available as an add-in for SOLIDWORKS.\nOverview.\nPower Surfacing uses subdivision surface (Sub-D) modeling and Non-uniform rational B-spline (NURBS) modeling methods together, to provide a flexible and intuitive way of designing organic shapes with high quality class A surfaces. Users can create and manipulate Sub-D models inside SOLIDWORKS, and convert them to NURBS models that are compatible with SOLIDWORKS features and commands. Power Surfacing also supports reverse engineering of scanned meshes with Power Surfacing RE, a separate add-in that can reconstruct Sub-D models from polygonal meshes.\nPower Surfacing is designed for industrial design, product design, automotive design, jewelry design, and other applications that require complex freeform surfaces. It aims to simplify the design process and reduce the editing time for organic shapes, compared to traditional surface creation methods. It also provides video tutorials and examples to help users learn how to use the software effectively.\nFeatures.\nSome of the features of Power Surfacing include:\nUsage.\nPower Surfacing functions as a generative design tool, generating iterative, evolutionary results based on initial constraints.\nThis tool is commonly used to optimize manufacturing processes for parts in various industries, such as automotive, packaging design, and medical implants.\nPower Surfacing can also reverse-engineer the shapes of 3D-scanned objects and recreate their geometry algorithmically, facilitating reproduction through industrial production processes. This capability can be employed to digitally replicate physical aspects of human anatomy, such as bones, and modify the model to produce precise-fitting physical Prosthesis for patients.", "Engineering,_Manufacturing": 0.9999809265, "qwen": "Yes"}
{"id": "55407740", "revid": "44312657", "url": "https://en.wikipedia.org/wiki?curid=55407740", "title": "Gas immersion laser doping", "text": "Gas immersion laser doping (GILD) is a method of doping a semiconductor material such as silicon.\nIn the case of doping silicon with boron to create a P-type semiconductor material, a thin wafer of silicon is placed in a containment chamber and is immersed in boron gas. A pulsed laser is directed at the silicon wafer and this results in localised melting and subsequent recrystallisation of the silicon wafer material, allowing boron atoms in the gas to diffuse into the molten sections of the silicon wafer. The result of this process is a silicon wafer with boron impurities, creating a P-type semiconductor.", "Engineering,_Manufacturing": 0.9999732971, "qwen": "Yes"}
{"id": "6711124", "revid": "33099684", "url": "https://en.wikipedia.org/wiki?curid=6711124", "title": "Haas Automation", "text": "Haas Automation, Inc is an American machine tool builder headquartered in Oxnard, California. The company designs and manufactures lower cost machine tools and specialized accessory tooling, mostly computer numerically controlled (CNC) equipment, such as vertical machining centers and horizontal machining centers, lathes/turning centers, and rotary tables and indexers. Most of its products are manufactured at the company's main facility in Oxnard. The company is also involved in motorsports: it owns the Haas F1 Team and is a co-owner of Stewart-Haas Racing in NASCAR. \nHaas is one of the largest machine tool builders in the world by total unit volume.\nHistory.\nGene Haas founded Haas Automation in 1983 to manufacture machine tool accessory tooling. The company entered the machine tool industry with the first fully automatic, programmable collet indexer. Over the next four years, the company expanded its product line to include fully programmable rotary tables, rotary indexers, and other machine tool accessories.\nIn 1987, Haas Automation began developing its first vertical machining center (VMC), the VF-1, a machine designed to perform operations such as milling, drilling, tapping, and boring. The first VF-1 prototypes were completed in 1988, and introduced at the International Manufacturing Technology Show (IMTS '88) in Chicago, Illinois.\nProducts.\nThe company manufactures several lines of CNC machine tools for the metalworking industry.\nVertical Mills.\nVF Series.\nVF series mills are a range of 3-axis vertical machining centers, which can be outfitted with 4th and 5th axis drives if so configured. These mills are available in different sizes, ranging from VF-1 to VF-14.\nThe VF in the name stands for \"Very First\" as the first machine Haas produced was the VF-1 (\"Very First One\"). One of these machines was restored by an employee, gifted to Gene Haas, and now resides in Haas's demo room in Oxnard, CA.\nUniversal Machines (UMC).\nHaas universal machining centers (known as UMC) are 5-axis bridge-type vertical machines. They were first introduced in 2015.\nMini Mill.\nThe mini mill was introduced as a small footprint alternative to the VF series mills, featuring a smaller casting while still maintaining a 40 taper spindle.\nToolroom Mills (TM).\nThe TM series was first introduced as essentially a \"CNC-capable toolroom mill”. Originally, these mills did not feature an enclosure, but have since been outfitted with an enclosure that encompasses the bottom and sides of the machine. These machines are characterized by a smaller casting and slower rapids, as they are targeted towards customers who do not require production capabilities.\nDrill/Tap/Mill Series (DT / DM).\nThe Haas DT series was originally introduced as a 30 taper high-speed machine, ideal for operations where high speed and small footprint are required, but the ability to handle large axial cutting loads is not needed. Eventually, the DM series was introduced as a 40 taper variant of the DT machine, but does not offer the 20,000 RPM spindle option.\nCompact Mill.\nThe CM is focused on machining small parts where high accuracy is required. The CM is a 20 taper machine, with spindles from 30,000 to 50,000 RPM. Haas only offers one machine in this series, the CM-1.\nGantry Series (GM / GR).\nGantry Series mills feature a static bed, a bridge that moves along the Y axis, and a head that moves along the X axis. The two primary use cases for GM series machines are large molds. GM series machines feature a more substantial casting with improved chip management as opposed to the GR series. The GM-2-5AX is also available, which is simply a GM-2 featuring two extra axes affixed to the head.\nCertifications.\nHaas Automation is an ISO 9001 certified company. All machine tools carry the ETL Listed mark, certifying that they conform to the NFPA 79 electrical standard for industrial machinery and the Canadian equivalent, CAN/CSA C22.2 No. 73. The company is also entitled to affix the CE mark to its products.\nSales.\nProducts are distributed worldwide through a network of independently owned franchised local \"factory outlet\" businesses that provide sales, service, and applications support for Haas machine tools. Introduced in 1999, with the first outlet established in Torrance, California, it was applied to the company's existing worldwide network, and then expanded to Europe.", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "4098143", "revid": "44357303", "url": "https://en.wikipedia.org/wiki?curid=4098143", "title": "Dynamic Materials Corporation", "text": "DMC Global Inc.  is a metalworking business headquartered in Broomfield, Colorado. It was formed in 1971, then known as Explosive Fabricators Inc.\nThe company operates in two segments, explosive metalworking and perforation (oil well). The explosive metalworking segment utilizes explosives to perform metal cladding and shock synthesis. Its principal product is an explosion welded clad metal plate, which is used in the construction of heavy, corrosion-resistant pressure vessels, and heat exchangers for petrochemical, refining, and hydrometallurgy industries.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "59965347", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=59965347", "title": "Responsive computer-aided design", "text": "Responsive computer-aided design (also simplified to responsive design) is an approach to computer-aided design (CAD) that utilizes real-world sensors and data to modify a three-dimensional (3D) computer model. The concept is related to cyber-physical systems through blurring of the virtual and physical worlds, however, applies specifically to the initial digital design of an object prior to production.\nThe process begins with a designer creating a basic design of an object using CAD software with parametric or algorithmic relationships. These relationships are then linked to physical sensors, allowing them to drive changes to the CAD model within the established parameters. Reasons to allow sensors to modify a CAD model include customizing a design to fit a user's anthropometry, assisting people without CAD skills to personalize a design, or automating part of an iterative design process in similar fashion to generative design. Once the sensors have affected the design it may then be manufactured as a one-off piece using a digital fabrication technology, or go through further development by a designer.\nContext.\nResponsive computer-aided design is enabled by ubiquitous computing and the Internet of Things, concepts which describe the capacity for everyday objects to contain computing and sensing technologies. It is also enabled by the ability to directly manufacture one-off objects from digital data, using technologies such as 3D printing and computer numerical control (CNC) machines. Such digital fabrication technologies allow for customization, and are drivers of the mass-customization phenomenon. They also provide new opportunities for consumers to participate in the design process, known as co-design.\nAs these concepts mature, responsive design is emerging as an opportunity to reduce reliance on graphical user interfaces (GUIs) as the only method for designers and consumers to design products, aligning with claims by Golden Krishna that \"the best design reduces work. The best computer is unseen. The best interaction is natural. The best interface is no interface.\" Calls to reduce reliance on GUIs and automate some of the design process connects with Mark Weiser's original vision of ubiquitous computing.\nRelated concepts.\nA variety of similar research areas are based on gesture recognition, with many projects using motion capture to track the physical motions of a designer and translate them into three-dimensional geometry suitable for digital fabrication. While these share similarities to responsive design through their cyber-physical systems, they require direct intent to design an object and some level of skill. These are not considered responsive, as responsive design occurs autonomously and may even occur without the user being aware that they are designing at all.\nThis topic has some common traits with responsive web design and responsive architecture, with both fields focused on systems design and adaptation based on functional conditions.\nCurrent work.\nResponsive computer-aided design has been used to customize fashion, and is currently an active area of research in footwear by large companies like New Balance who are looking to customize shoe midsoles using foot pressure data from customers.\nSound waves have also been popular to customize 3D models and produce sculptural forms of a baby's first cries, or a favorite song.", "Engineering,_Manufacturing": 0.9940679073, "qwen": "Yes"}
{"id": "59980675", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=59980675", "title": "Implant induction welding of thermoplastics", "text": "Implant induction welding is a joining method used in plastic manufacturing. The welding process uses an induction coil to excite and heat electromagnetically susceptible material at the joint interface and melt the thermoplastic. The susceptible material can be contained in a gasket placed between the welding surface, or within the actual components of a composite material. Its usage is common for large, unusually shaped, or delicate parts that would be difficult to weld through other methods.\nPhysical Mechanisms.\nIn non-magnetic electrical conductors like aluminum, nickel, or copper, an alternating electromagnetic field will induce Eddy currents in the material. These currents generate thermal energy through Joule heating. Ferromagnetic materials like iron and carbon steels will see heating from both Eddy current formation and Hysteresis losses.\nWelding Process.\nMaterial Considerations.\nInduction heating is an efficient method of heating electrically conductive or magnetic materials. Warm-up times are minimal and direct contact with the part is not needed. Unfortunately most thermoplastics are non-magnetic and excellent insulators. To take advantage of induction heating for thermoplastic welding purposes, a susceptible implant must be used as an intermediary material. Nearly any electrical conductor or ferromagnetic material may be used as an implant. Implant styles include meshes, fibers, and fine powders. The most common gasket design is a thermoplastic composite with suspended susceptible fibers. . This composite gasket can be formed into any shape required for the welding application. The gasket matrix is typically made of the same thermoplastic being welded. In situations where two dissimilar materials are to be welded, the gasket material is usually a blend of the two thermoplastics.\nComposite Materials.\nCarbon fiber is of interest due to its widespread use in composite materials. Provided there are closed loops of carbon within the composite structure, eddy currents can be induced in the material. Unidirectional carbon fiber composites can have poor susceptibility when fiber to fiber contact is limited.\nFocusing heat only at the weld point is difficult with susceptible composite fibers throughout the material. In carbon fiber composites, thin electrically insulating layers with non-aligned fibers may be inserted between conducting layers to electrically isolate the joint surface from the material bulk. Using this technique, induction heating of the bulk is avoided.\nEquipment.\nAn induction generator is used to produce high frequency current in the range of 2-10 Mhz. The range used is regulated by the FCC to avoid interference with broadcast signals.\nAn induction coil converts the high frequency current from the induction generator into the necessary alternating magnetic field. A single turn coil may be used when space is limited, however multiturn coil designs are more common due to their generation of a stronger and deeper penetrating magnetic field. Split coil designs are also available, which may be dissasembeled to fully surround a large part such as plastic piping. The high currents used in induction welding produce large amounts of heat in the coil. To avoid overheating, the coil turns are made with hollow tubing, and water is circulated during welding. Coil heat is dissipated by an attached heat exchanger.\nFixtures are used to hold the parts in position during welding. One fixture is fixed and the other moveable so that a press may apply and maintain pressure during heating and cooling.\nWelding Steps.\nAn implant rich gasket is placed at the surface to be welded. Pressure is applied to the joint to force out air cavities and ensure a sound bond. An electromagnetic field is applied by the induction coil to heat the implants, and pressure is applied to the joint. Heat conducts into the surrounding thermoplastic, which melts the gasket and creates a melt layer at the joint surfaces. The applied pressure flows the molten thermoplastic and fills the joint. When sufficient bonding has been achieved, the induction coil is turned off and the joint is cooled under pressure. For large items with long joints, the joint can be welded continuously by scanning the active coil along the length of the interface.\nParameters.\nPower.\nTypical induction generators provide a power output of 1-5 kWs. High power output is necessary for longer and larger joints. Power output must also be increased as coil distance from the joint increases, due to electromagnetic field decay.\nPressure.\nEven distribution of the molten polymer in the joint is imperative for strong bonding. Weld pressure must be sufficient to induce squeeze flow in the molten gasket, achieve intimate contact with the joint surface, and fill the joint.\nWeld Time and Cooling Time.\nWeld time will vary based on the joint size, the volume of susceptible implant material, and the power and frequency. Cycle times can be very fast since no preheating is needed, and heat generation happens exclusively at the weld joint. This also benefits the cooling time. With little heat wasted on the bulk of the part, cooling is brief. Under 1 second for some applications.\nJoint Design.\nUnusual joint designs are possible using implant induction welding. The simplest is the flat to flat joint, where a gasket is placed between two thermoplastic plates. This joint is common for continuous welding processes, or long weld lines where the active coil is scanned along the joint interface. The flat to groove joint uses a plate with a channel to accurately align the weld versus the flat to flat joint. The tongue in groove joint is similar to the flat to groove joint, but has the advantage of complete encapsulation of the gasket and a pressure tight seal.\nApplications.\nFood Packaging.\nImplant induction welding is heavily used in the production of Tetra Pak containers for products like juice boxes. The use of induction heating shortens the sealing time versus other joining methods that use external heat, and avoids damage to the paperboard layer from direct contact with hot tooling. An aluminum foil layer is used to block oxygen diffusion into the packaging, so no additional implant material is needed.\nAutomotive Manufacturing.\nThe automotive industry makes large scale use of implant induction welding for the manufacture of large plastic items such as bumpers, plastic body panels, and fuel tanks. Manufacturing costs of components with complex geometries are brought down by manufacturing the parts in separate pieces, to be assembled later using induction welding.\nTamper Proof Packaging.\nPolyethylene coated aluminum foil is induction welded to the top of many food, supplement, and drug containers. The seal helps retain product quality and provides evidence of tampering.", "Engineering,_Manufacturing": 1.0000063181, "qwen": "Yes"}
{"id": "13189722", "revid": "5229428", "url": "https://en.wikipedia.org/wiki?curid=13189722", "title": "Industrial digital printer", "text": "Industrial Digital Printers can be divided into a variety of different categories. As the industry becomes more mature, and the number of manufacturers increases, the line between the broad descriptions becomes less defined.\nDigital Printers are sometimes erroneously referred to as being “Digital Printing Presses”. The term Printing Press refers to the nature of the process, in which there is contact between the system that applies the ink to the substrate and substrate that the ink is pressed onto. Digital Printers however are non-impact printing processes; to print, a devices “fires” drops of ink from the print heads onto the substrate.\nCategories.\nHere is a broad outline of classes of digital printers in the graphic arts segment of the printing industry.\nHigh volume.\nThese systems print at speeds measured at between 200 and 400 square metres per hour.\nSuper wide format.\nThese printers are generally roll-to-roll and have a print bed that is 2m to 5m wide. Mostly used for printing billboards and generally have the capability of printing between 60 and 160 square metres per hour. Traditionally these were manufactured by Western manufacturers, however in the last 5 to 10 years Korean, Japanese and Chinese printer manufacturers have been aggressively competing in this category with more reliable faster printers. Margins dictate that many well-known European brands are currently manufactured in the East and simply rebranded in Europe and the United States for distribution around the world. Market antipathy to products manufactured in the East is becoming obsolescent as the vast majority of products used commercially are either assembled complete in the East or have their parts manufactured and exported from there. The low manufacturing costs of parts and machines in the East would make it extremely difficult for super-wide format digital printer suppliers around the world to compete profitably unless they turned to countries like China, Korea and Japan for their manufacturing.\nWide format.\nThese printers are most commonly manufactured in Korea and China with India starting to develop printers as well. These machines are now available from 0.9 metres to 3 metres wide. Generally they are capable of printing from 10 to 60 square metres per hour.\nHigh resolution.\nPrinters are generally referred to as \"Super-Wide format\" when their print bed exceeds 2.2m in width. For many applications at this size resolution becomes secondary to print speed - which is why many machines over 3m wide are designed for speed over resolution. In the 1980s billboards were generally printed at resolutions as low as 80dpi (dots per inch). Resolutions today are much higher because of the improvements in technology but printing billboards, vehicle graphics, building wraps and the like do not require the ultra-high resolutions of 1440dpi and upwards often associated with standard wide format printers. It is normal for super-wide format digital printers to function at maximum resolutions of between 540dpi and around 1040dpi. However even these resolutions are rarely used in a production environment, billboards and building wraps for example are often done at between 200dpi and 350dpi and the result relies on the viewing distance for the impactful, colourful graphics the public sees on roadsides and buildings. The fact that they are capable of printing at these higher resolutions is still important though because it attests to the size of the ink droplet being laid down by the inkjet solvent and eco-solvent machines. These ink droplets are measured in pica-litres and a print done at 200dpi will look more defined if it is printed with smaller ink droplets when compared to a machine laying down bigger ink droplets. The primary print head technologies used in ultra-wide format digital outdoor printing comes down to a few print head manufacturers worldwide including (but not restricted to) Piezo, Seiko and Spectra as the primary competitors and their print heads are used in most machines from a variety of manufacturers. They have their pros and cons and Piezo appears to focus more on the higher resolution side of the industry whereas Seiko and Spectra-Polaris tend more towards the robust, high production capabilities required in a manufacturing environment.\nPrint heads.\nAt this time these printers use printers using PZT crystals as micro-pumps to eject the droplets from the nozzles. The crystals deform to generate a “shock wave” in the fluid inks which in turn ejects a drop from the nozzle. A combination of surface tension, capillary pressure and other complex fluid dynamics ensures that the fluid is refilled ready for the next fire cycle.", "Engineering,_Manufacturing": 0.9997326732, "qwen": "Yes"}
{"id": "58070834", "revid": "957305395", "url": "https://en.wikipedia.org/wiki?curid=58070834", "title": "Non functional pad", "text": "A non-functional pad is a pad in a printed circuit board that is not connected to a track on the layer it is on.\nRemoval.\nNon-functional pads can be removed at any phase of the design process. Some software allows precise control during the design process, and also removes the non-functional pads during output file creation. Furthermore, some board manufacturers remove non-functional pads during data preparations. \nOccasionally, this process of non-functional pad removal is also called unused pad suppression.\nThe benefits of removing the non-functional pads are limited. Electrically, it creates needless extra capacitance in certain designs, which needs to be removed. Removing non-functional pads can improve the drilling process, as it lessens drill wear. \nNon-functional pad removal can influence the reliability. (e.g. barrel cracking failure mode). Removal can increase or decrease reliability. Depending on design parameters, removing the non-functional pads can free up routing space. \nNon-functional pads naturally also affect thermal characteristics.\nSometimes, non-functional pads (or their removal) are used for copper balancing, which affects etching, bow and twist and other effects.", "Engineering,_Manufacturing": 0.9996906519, "qwen": "Yes"}
{"id": "2445044", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=2445044", "title": "Deep reactive-ion etching", "text": "Deep reactive-ion etching (DRIE) is a highly anisotropic etch process used to create deep penetration, steep-sided holes and trenches in wafers/substrates, typically with high aspect ratios. It was developed for microelectromechanical systems (MEMS), which require these features, but is also used to excavate trenches for high-density capacitors for DRAM and more recently for creating through silicon vias (TSVs) in advanced 3D wafer level packaging technology. In DRIE, the substrate is placed inside a reactor, and several gases are introduced. A plasma is struck in the gas mixture which breaks the gas molecules into ions. The ions accelerated towards, and react with the surface of the material being etched, forming another gaseous element. This is known as the chemical part of the reactive ion etching. There is also a physical part, if ions have enough energy, they can knock atoms out of the material to be etched without chemical reaction. \nDRIE is a special subclass of RIE.\nThere are two main technologies for high-rate DRIE: cryogenic and Bosch, although the Bosch process is the only recognised production technique. Both Bosch and cryo processes can fabricate 90° (truly vertical) walls, but often the walls are slightly tapered, e.g. 88° (\"reentrant\") or 92° (\"retrograde\").\nAnother mechanism is sidewall passivation: SiOxFy functional groups (which originate from sulphur hexafluoride and oxygen etch gases) condense on the sidewalls, and protect them from lateral etching. As a combination of these processes deep vertical structures can be made.\nCryogenic process.\nIn cryogenic-DRIE, the wafer is chilled to −110 °C (163 K). The low temperature slows down the chemical reaction that produces isotropic etching. However, ions continue to bombard upward-facing surfaces and etch them away. This process produces trenches with highly vertical sidewalls. The primary issues with cryo-DRIE is that the standard masks on substrates crack under the extreme cold, plus etch by-products have a tendency of depositing on the nearest cold surface, i.e. the substrate or electrode.\nBosch process.\nThe Bosch process, named after the German company Robert Bosch GmbH which patented the process, also known as pulsed or time-multiplexed etching, alternates repeatedly between two modes to achieve nearly vertical structures:\nEach phase lasts for several seconds. The passivation layer protects the entire substrate from further chemical attack and prevents further etching. However, during the etching phase, the directional ions that bombard the substrate attack the passivation layer at the bottom of the trench (but not along the sides). They collide with it and sputter it off, exposing the substrate to the chemical etchant.\nThese etch/deposit steps are repeated many times over resulting in a large number of very small isotropic etch steps taking place only at the bottom of the etched pits. To etch through a 0.5 mm silicon wafer, for example, 100–1000 etch/deposit steps are needed. The two-phase process causes the sidewalls to undulate with an amplitude of about 100–500 nm. The cycle time can be adjusted: short cycles yield smoother walls, and long cycles yield a higher etch rate.\nApplications.\nRIE \"deepness\" depends on application:\nWhat distinguishes DRIE from RIE is etch depth: Practical etch depths for RIE (as used in IC manufacturing) would be limited to around 10 µm at a rate up to 1 µm/min, while DRIE can etch features much greater, up to 600 µm or more with rates up to 20 µm/min or more in some applications.\nDRIE of glass requires high plasma power, which makes it difficult to find suitable mask materials for truly deep etching. Polysilicon and nickel are used for 10–50 µm etched depths. In DRIE of polymers, Bosch process with alternating steps of SF6 etching and C4F8 passivation take place. Metal masks can be used, however they are expensive to use since several additional photo and deposition steps are always required. Metal masks are not necessary however on various substrates (Si [up to 800 µm], InP [up to 40 µm] or glass [up to 12 µm]) if using chemically amplified negative resists.\nGallium ion implantion can be used as etch mask in cryo-DRIE. Combined nanofabrication process of focused ion beam and cryo-DRIE was first reported by N Chekurov \"et al\" in their article \"The fabrication of silicon nanostructures by local gallium implantation and cryogenic deep reactive ion etching\".\nPrecision Machinery.\nDRIE has enabled the use of silicon mechanical components in high-end wristwatches. According to an engineer at Cartier, “There is no limit to geometric shapes with DRIE,”. With DRIE it is possible to obtain an aspect ratio of 30 or more, meaning that a surface can be etched with a vertical-walled trench 30 times deeper than its width.\nThis has allowed for silicon components to be substituted for some parts which are usually made of steel, such as the hairspring. Silicon is lighter and harder than steel, which carries benefits but makes the manufacturing process more challenging.", "Engineering,_Manufacturing": 0.9998733997, "qwen": "Yes"}
{"id": "3218944", "revid": "5846", "url": "https://en.wikipedia.org/wiki?curid=3218944", "title": "Push–pull strategy", "text": "The business terms push and pull originated in logistics and supply chain management, but are also widely used in marketing and in the hotel distribution business.\nWalmart is an example of a company that uses the push vs. pull strategy.\nSupply-chain management.\nComplete definition.\nThere are several definitions on the distinction between push and pull strategies. Liberopoulos (2013) identifies three such definitions: \nOther definitions are:\nInformation flow.\nWith a push-based supply chain, products are pushed through the channel, from the production side up to the retailer. The manufacturer sets production at a level in accord with historical ordering patterns from retailers. It takes longer for a push-based supply chain to respond to changes in demand, which can result in overstocking or bottlenecks and delays (the bullwhip effect), unacceptable service levels and product obsolescence.\nIn a pull-based supply chain, procurement, production and distribution are demand-driven rather than to forecast. However, a pull strategy does not always require make to order production. Toyota Motors Manufacturing is frequently used as an example of pull production, yet do not typically produce to order. They follow the \"supermarket model\" where limited inventory is kept on hand and is replenished as it is consumed. In Toyota's case, Kanban cards are used to signal the need to replenish inventory.\nA supply chain is almost always a combination of both push and pull, where the interface between the push-based stages and the pull-based stages is sometimes known as the \"push–pull boundary\". However, because of the subtle difference between pull production and make-to-order production, a more accurate name for this may be the \"customer order decoupling point\". An example of this is Dell's build to order supply chain. Inventory levels of individual components are determined by forecasting general demand, but final assembly is in response to a specific customer request. The decoupling point would then be at the beginning of the assembly line.\nIn a marketing \"pull\" system, the consumer requests the product and \"pulls\" it through the delivery channel. An example of this is the car manufacturing company Ford Australia. Ford Australia only produces cars when they have been ordered by customers.\nUse of pull, push, and hybrid push-pull strategy.\nHarrison summarized when to use each one of the three supply chain strategies:\nExamples in \"push\" and \"pull\".\nHopp and Spearman consider some of the most common systems found in industry and the literature and classify them as either push or pull\nLiberopoulos (2013) also classifies common systems according to different definitions on the distinction between push and pull.\nMarketing.\nAn advertising push strategy refers to a situation when a vendor advertises its product to gain audience awareness, while the pull strategy implies the aims to reach audiences which have shown existing interest in the product or information about it. The difference between \"push\" and \"pull\" marketing can also be identified by the manner in which the company approaches the lead. If, for example, the company were to send a sales brochure, that would be considered pushing the opportunity toward the lead. If, instead, the company provided a subject matter expert as a speaker for an industry event attended by targeted leads, that could be one tactic used as part of a strategy to pull in a lead by encouraging that lead to seek out the expert in a moment of need for that expertise.\nHotel distribution.\nThe online world has brought this pull push decision to the hotel distribution business ", "Engineering,_Manufacturing": 0.9984339476, "qwen": "Yes"}
{"id": "3224804", "revid": "39191556", "url": "https://en.wikipedia.org/wiki?curid=3224804", "title": "United Nations Humanitarian Response Depot", "text": "The United Nations Humanitarian Response Depot (UNHRD) is an international network of six humanitarian support hubs located strategically around the world, that provide supply chain solutions to the international humanitarian community. The hubs are located in Brindisi (Italy), Dubai (UAE), Accra (Ghana), Panama City (Panama), Kuala Lumpur (Malaysia) and Las Palmas (Spain).\nIt is managed by the World Food Programme and currently serves 86 partners, such as UN organizations, government agencies and NGOs. It enables these partners to assist people affected by natural disasters or other complex emergencies by prepositioning vital relief items and allowing them to be dispatched rapidly to critical areas. In addition, the UNHRD network offers services and knowledge that allow various humanitarian partners to fulfill their missions rapidly and effectively.\nBackground.\nToday's UNHRD Network dates back to an initiative by the Italian government in the mid-1980s: to pre-position relief items and support equipment for humanitarian operations at its military airport facilities. Expanding on the success of this method and envisioning a global network, WFP transformed the humanitarian depot into a logistic hub for emergency preparedness and response. In line with the United Nations Reforms for better coordinated development system and more effective humanitarian structures, UNHRD enhances the efficiency and effectiveness of humanitarian assistance, with the specific mandate to \"assist the population living in countries affected by natural disasters or complex emergencies, through a prepositioning of relief and survival items and their rapid demobilization to the affected countries.\"\nHistory.\nThe original UNHRD depot was inaugurated in Brindisi in the year 2000 to replace the United Nations Supply Depot (UNSD) in Pisa, then managed by the Office of Coordination of Humanitarian Affairs (OCHA). Upon decision of the Inter-Agency Standing Committee (IASC) the mandate to provide rapid and accessible stockpiling and demobilisation services to partners inside and outside the United Nations was transferred from OCHA to WFP. Subsequently, the hub was moved to the military airport at Brindisi in an effort to set up a new and robust logistics platform, available to all partners as a \"shared resource\".\nIn 2006, based on its own requirements and that of its partners, WFP replicated the successful Brindisi model by setting up further emergency response facilities in strategic locations worldwide, creating a network of HRDs in Africa, the Middle East, South East Asia and Latin America. Each of these locations has been selected to provide easy access to an airport, port and road systems, making access to a wide range of transportation methods available and allowing for consistently low response times of 24-48 hours.\nFunctions.\nWhen Governments, UN agencies and NGOs look to respond quickly and efficiently to a disaster, they call on emergency supplies that are immediately available in UNHRD warehouses. By prepositioning relief items, the humanitarian community can support affected people at the very beginning of an emergency, often saving lives within the first 24–48 hours.\nUNHRD offers a range of supply chain solutions to relief organizations around the globe, acting as a 'one-stop shop' to its partners for storage, procurement, transport, handling, stock borrowing, technical field assistance and training centre facilities.\nFigures.\nOriginally, five humanitarian organisations relied on the UNHRD Network, including WFP itself. This number has since grown to 86 in 2017. Partner organisations that join the network are diverse, spanning UN agencies, governmental and non-governmental organisations.\nIn 2017, the UNHRD Network managed 575 shipments in 95 countries supporting 36 partners in responding to humanitarian emergencies, including Hurricane Irma, the Rohingya Refugees Crisis in Bangladesh, and the South Sudanese Refugee Crisis in Uganda.", "Engineering,_Manufacturing": 0.9800671339, "qwen": "Yes"}
{"id": "3225534", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=3225534", "title": "Scheduling (production processes)", "text": "Scheduling is the process of arranging, controlling and optimizing work and workloads in a production process or manufacturing process. Scheduling is used to allocate plant and machinery resources, plan human resources, plan production processes and purchase materials.\nIt is an important tool for manufacturing and engineering, where it can have a major impact on the productivity of a process. In manufacturing, the purpose of scheduling is to keep due dates of customers and then minimize the production time and costs, by telling a production facility when to make, with which staff, and on which equipment. Production scheduling aims to maximize the efficiency of the operation, utilize maximum resources available and reduce costs.\nIn some situations, scheduling can involve random attributes, such as random processing times, random due dates, random weights, and stochastic machine breakdowns. In this case, the scheduling problems are referred to as \"stochastic scheduling\".\nOverview.\nScheduling is the process of arranging, controlling and optimizing work and workloads in a production process. Companies use backward and forward scheduling to allocate plant and machinery resources, plan human resources, plan production processes and purchase materials.\nThe benefits of production scheduling include:\nProduction scheduling tools greatly outperform older manual scheduling methods. These provide the production scheduler with powerful graphical interfaces which can be used to visually optimize real-time work loads in various stages of production, and pattern recognition allows the software to automatically create scheduling opportunities which might not be apparent without this view into the data. For example, an airline might wish to minimize the number of airport gates required for its aircraft, in order to reduce costs, and scheduling software can allow the planners to see how this can be done, by analysing time tables, aircraft usage, or the flow of passengers.\nKey concepts in scheduling.\nA key character of scheduling is the productivity, the relation between quantity of inputs and quantity of output. Key concepts here are:\nScheduling algorithms.\nProduction scheduling can take a significant amount of computing power if there are a large number of tasks. Therefore, a range of short-cut algorithms (heuristics) (a.k.a. dispatching rules) are used:\nBatch production scheduling.\nBackground.\nBatch production scheduling is the practice of planning and scheduling of batch manufacturing processes. See Batch production. Although scheduling may apply to traditionally continuous processes such as refining, it is especially important for batch processes such as those for pharmaceutical active ingredients, biotechnology processes and many specialty chemical processes. Batch production scheduling shares some concepts and techniques with finite capacity scheduling which has been applied to many manufacturing problems. The specific issues of scheduling batch manufacturing processes have generated considerable industrial and academic interest.\nScheduling in the batch processing environment.\nA batch process can be described in terms of a recipe which comprises a bill of materials and operating instructions which describe how to make the product. The ISA S88 batch process control standard provides a framework for describing a batch process recipe. The standard provides a procedural hierarchy for a recipe. A recipe may be organized into a series of unit-procedures or major steps. Unit-procedures are organized into operations, and operations may be further organized into phases.\nThe following text-book recipe illustrates the organization.\nA simplified S88-style procedural organization of the recipe might appear as follows:\nNote that the organization here is intended to capture the entire process for scheduling. A recipe for process-control purposes may have a more narrow scope.\nMost of the constraints and restrictions described by Pinedo are applicable in batch processing. The various operations in a recipe are subject to timing or precedence constraints that describe when they start and or end with respect to each other. Furthermore, because materials may be perishable or unstable, waiting between successive operations may be limited or impossible. Operation durations may be fixed or they may depend on the durations of other operations.\nIn addition to process equipment, batch process activities may require labor, materials, utilities and extra equipment.\nCycle-time analysis.\nIn some simple cases, an analysis of the recipe can reveal the maximum production rate and the rate limiting unit. In the process example above if a number of batches or lots of Product C are to be produced, it is useful to calculate the minimum time between consecutive batch starts (cycle-time). If a batch is allowed to start before the end of the prior batch the minimum cycle-time is given by the following relationship:\nformula_1\nWhere CTmin is the shortest possible cycle time for a process with M unit-procedures and τj is the total duration for the jth unit-procedure. The unit-procedure with the maximum duration is sometimes referred to as the bottleneck. This relationship applies when each unit-procedure has a single dedicated equipment unit.\nIf redundant equipment units are available for at least one unit-procedure, the minimum cycle-time becomes:\nformula_2\nWhere is the number of redundant equipment for unit procedure .\nIf equipment is reused within a process, the minimum cycle-time becomes more dependent on particular process details. For example, if the drying procedure in the current example is replaced with another reaction in the reactor, the minimum cycle time depends on the operating policy and on the relative durations of other procedures. In the cases below, an increase in the hold time in the tote can decrease the average minimum cycle time.\nVisualization.\nVarious charts are used to help schedulers visually manage schedules and constraints. The Gantt chart is a display that shows activities on a horizontal bar graph in which the bars represent the time of the activity. Below is an example of a Gantt chart for the process in the example described above.\nAnother time chart which is also sometimes called a Gantt chart shows the time during which key resources, e.g. equipment, are occupied. The previous figures show this occupancy-style Gantt chart.\nResources that are consumed on a rate basis, e.g. electrical power, steam or labor, are generally displayed as consumption rate vs time plots.\nAlgorithmic methods.\nWhen scheduling situations become more complicated, for example when two or more processes share resources, it may be difficult to find the best schedule. A number of common scheduling problems, including variations on the example described above, fall into a class of problems that become very difficult to solve as their size (number of procedures and operations) grows.\nA wide variety of algorithms and approaches have been applied to batch process scheduling. Early methods, which were implemented in some MRP systems assumed infinite capacity and depended only on the batch time. Such methods did not account for any resources, and would produce infeasible schedules.\nMathematical programming methods involve formulating the scheduling problem as an optimization problem where some objective, e.g. total duration, must be minimized (or maximized) subject to a series of constraints which are generally stated as a set of inequalities and equalities. The objective and constraints may involve zero-or-one (integer) variables as well as nonlinear relationships. An appropriate solver is applied for the resulting mixed-integer linear or nonlinear programming (MILP/MINLP) problem. The approach is theoretically guaranteed to find an optimal solution if one exists. The disadvantage is that the solver algorithm may take an unreasonable amount of time. Practitioners may use problem-specific simplifications in the formulation to get faster solutions without eliminating critical components of the scheduling model.\nConstraint programming is a similar approach except that the problem is formulated only as a set of constraints and the goal is to arrive at a feasible solution rapidly. Multiple solutions are possible with this method.\nAgent-based modeling describes the batch process and constructs a feasible schedule under various constraints. By combining with mixed-integer programming or simulated-based optimization methods, this approach could achieve a good balance between the solution efficiency and the schedule performance. A new development and framework addresses how to exploit the aggregation of several digital twins, representing different physical assets and their autonomous decision-making, together with a global digital twin, in order to perform production scheduling optimization.", "Engineering,_Manufacturing": 1.0000066757, "qwen": "Yes"}
{"id": "41003302", "revid": "1156928414", "url": "https://en.wikipedia.org/wiki?curid=41003302", "title": "List of fuel cell manufacturers", "text": "A fuel cell is an electrochemical energy conversion device. Fuel cells differ from batteries in that they are designed for continuous replenishment of the reactants consumed.\nThis is a partial list of companies currently producing commercially available fuel cell systems for use in residential, commercial, or industrial settings. Fuel cell systems from these manufacturers are currently being used to generate AC or DC electricity, heat, water, or any combination of the three. ", "Engineering,_Manufacturing": 0.9998679161, "qwen": "Yes"}
{"id": "64081495", "revid": "12023796", "url": "https://en.wikipedia.org/wiki?curid=64081495", "title": "High-area rapid printing", "text": "High-area rapid printing (HARP) is a stereolithography (SLA) method that permits the continuous, high-throughput printing of large objects at rapid speeds (Figure 1). This method was introduced in 2019 by the Mirkin Research Group at Northwestern University in order to address drawbacks associated with traditional SLA manufacturing processes. Since the polymerization reactions involved in SLA are highly exothermic processes, the production of objects at high-throughputs is associated with high temperatures that can result in structural defects. HARP addresses this problem by utilizing a solid-liquid slip boundary (Figure 2) that cools the resin by withdrawing heat from the system. This allows for large structures to be fabricated quickly without the temperature-associated defects inherent to other SLA processes.\nDesign and Advantages.\nAdditive manufacturing, or 3D printing, has allowed for the rapid prototyping of intricate structures that are not accessible via traditional manufacturing processes and has found specific applications in tissue engineering and high-strength materials production. SLA is one such approach, which typically utilizes ultraviolet light to cure a photoactive resin onto a vertically moving plate. Stereolithography is traditionally realized by printing successive 2D layers between the vertically moving plate and the bottom of the vat in order to build up a three-dimensional (3D) object. This process is time-consuming as each layer must be mechanically cleaved from the bottom of the resin vat before another layer can be printed. Recent advances employ an oxygen “dead zone” between the bottom of the vat and the polymerized object to achieve continuous liquid interface production (CLIP). Because the polymerizing object is no longer in contact with the bottom of the resin vat, mechanical cleavage is not necessary, making CLIP a continuous stereolithographic process. CLIP is being used by Carbon 3D to manufacture parts approximately 100 times faster than traditional SLA methodologies. At these print speeds, however, the heat generated from the exothermic polymerization reactions can result in deformation of the printed object.\nHARP utilizes a circulating fluorinated oil layer below the resin to remove heat at the boundary between the oil and the resin, cooling the system (Figure 2). The fluorinated oil is circulated at a rate that supports the formation of a solid-liquid slip boundary, and therefore, low adhesion between the printed object and the transparent vat. The slip boundary ensures uniformity of both topology and temperature across the interface and allows for continuous printing but at substantially higher throughputs than CLIP. The heat dissipation is a consequence of the direct contact between the fluorinated oil and the hot, polymerizing resin, since heat is effectively transferred from the resin to the oil. The hot oil is then flowed out of the reaction bath, cooled, filtered, and subsequently reintroduced into the system. Thus, control over the temperature of the system is attained. Even the printing of small structures via a SLA process at high-throughput without cooling results in temperatures at which deformation of the desired structure occurs (Figure 3A). In contrast, when HARP is used with cooling, markedly decreased temperatures are observed without a reduction in part quality (Figure 3C). HARP is also compatible with traditional stereolithographic resins; this has been demonstrated with polyurethane acrylate, butadiene rubber, and silicon carbide ceramic.  At the time of writing, HARP had printed the largest structure based on SLA 3D printing (0.30 x 0.30 x 1.2-meters) to date in approximately three hours (Figure 1).\nProfessor Chad Mirkin, Dr. James Hedrick, and Dr. David Walker founded Azul3D (previously CDJ Technologies) for the purpose of commercializing the HARP platform. ", "Engineering,_Manufacturing": 0.9997768998, "qwen": "Yes"}
{"id": "46402433", "revid": "19295592", "url": "https://en.wikipedia.org/wiki?curid=46402433", "title": "Projection micro-stereolithography", "text": "Projection micro-stereolithography (PµSL) adapts 3D printing technology for micro-fabrication. Digital micro display technology provides dynamic stereolithography masks that work as a virtual photomask. This technique allows for rapid photopolymerization of an entire layer with a flash of UV illumination at micro-scale resolution. The mask can control individual pixel light intensity, allowing control of material properties of the fabricated structure with desired spatial distribution.\nMaterials include polymers, responsive hydrogels, shape memory polymers and bio-materials.\nIntroduction.\nThe micro electro-mechanical systems (MEMS) is developing quickly in the past 30 years. Relying on the integration of sensors and actuators, MEMS always demand cheaper, easier and more precise method to fabricate micro size 3-D structures using different materials such as polymers, ceramics and semiconductor materials. The appearance of the Projection Micro-stereolithography improves the development of MEMS by achieving most of the requirements above. This invention is based on the stereolithography (3D printing), which developed by Charles Hull in 1984. This machine is primarily used to fabricate soft materials such as hydro gels and polymers. The basic theory behind this invention is using UV light to cure the solution, which consists initiators, monomers and absorbers, to form each layer of materials. Under the exposure of UV light, the initiators are transferred into the radicals. Radicals connect monomers together to begin the polymerization process. The absorbers are mixed with monomers to control the depth of UV light penetration. This chemical process allows the areas under UV exposure to become solid state polymers.\nHistory.\nAt first, all micro size stereolithography method utilized the same method as the macro size stereolithography that they direct write materials on the base. The first micro size stereolithography that use the UV light to cure the liquid resin surface is developed by professor Ikuta and Hirowatari in 1993. This fabrication approach is the prototype of today's projection micro-stereolithography. Compared with previous direct writing fabrication methods, this approach has the advantage that it can fabricate each layer simultaneously which increases the yield rate for large production. At that time, 2D shape data was obtained in a CAD system. The 2D data is used to fabricate 2D sliced planes in the liquid. Therefore, several 2D planes have to be made in the CAD system for complicated structures. This stereolithography can be used to fabricate both polymers and metals. Metals are fabricated using the casting process after a polymer mold is made. Although improves the yield rate, this method requires a mask for each layer of the final product, which increases process time and cost. Therefore, the fabricate technology is developed again that the masks are replaced by the micromirror display device, which is similar to the projector in our daily life. The micromirror display provides a dynamic mask that can change the patterns electronically. Since multiple masks are displaced by one mask, the processing time and fabrication cost are greatly decrease.\nProcess.\nThe dynamic mask defines the beam. The beam is focused on the surface of a UV-curable polymer resin through a projection lens that reduces the image to the desired size. Once a layer is polymerized, the stage drops the substrate by a predefined layer thickness, and the dynamic mask displays the image for the next layer on top of the preceding one. This proceeds iteratively until complete. The process can create layer thickness on the order of 400 nm.\nSub 2 µm horizontal and sub-1 µm vertical resolutions have been achieved, with sub-1 µm feature sizes. Process can work at ambient temperature and atmosphere, although increased nitrogen improves polymerization Production rates of 4 cu mm/hr have been achieved, depending on resin viscosity.\nMaterials can be easily switched during fabrication, enabling integration of multiple material elements in a single process.\nApplications.\nApplications include fabricating microactuators, creating molds, electroplating or (with resin additives) ceramic items, including micro-bio reactors to support tissue growth, micromatrices for drug delivery and detection and biochemical integrated circuits to simulate biological systems.\nMicroactuator.\nInspired by Mimosa pudica, the leaf of this actuator can swell upon the external stimulations such as solvents, temperature and light. In order to control the motion of this actuator, microfluidic channels are embedded inside the leaf of this actuator. With both complex external geometries and internal structures, this soft microactuator can be fabricated using Projection Micro-stereolithography, which is one of the easiest ways to obtain this complex 3D structures. The CAD mold of this actuator is generated in a computer. The sliced 2D images are obtained next. Each 2D image is then projected by the micromirror display and go through the lens to a desired size to the surface of the polymer resin. Since Projection Micro-stereolithography is time-saving, the same experiment can be done on different liquid soft materials in order to learn the swelling effect of them. Based on this contraction and extension of materials caused by a small drop of solvent or a small change in environmental conditions, this microactuator can mimic the motion of the human muscle and can be used on many soft robotic applications.\nArtificial Tissue.\nMany reconstructive surgery procedures require new tissues when the original tissues are removed because of illnesses. One way to generate this new tissue is to take one part of tissue from another part of the human body and transfer it to the new site. However, this method causes damage to other organs while generating new tissues. Therefore, fabricating artificial tissues is a preferred approach to solve this problem. The major limitation of this artificial tissue is the absence of the capillary system to transport nutrient and oxygen like the circulatory systems in living organisms. With the ability to fabricate complex 3D structures, the Projection Micro-stereolithography may provide one of the best solutions to this tissue. Like the microactuator, the mold of the artificial tissue is made by CAD. Then the CAD mold is transferred to 2D images and projected to the surface of the polymer resin through a lens. The capillary system is embedded in the tissue during the mold designing process in the CAD mold. The polymer used in fabricating the tissue is semi-permeable, which allows the nutrient and oxygen in the capillary system go into the tissue during the transportation process. The capillary system is shown to have growth promoting function in yeast cells, which illustrate the viability of this artificial tissue.", "Engineering,_Manufacturing": 0.9995001554, "qwen": "Yes"}
{"id": "20998975", "revid": "29463730", "url": "https://en.wikipedia.org/wiki?curid=20998975", "title": "Channel-stopper", "text": "In semiconductor device fabrication, channel-stopper or channel-stop is an area in semiconductor devices produced by implantation or diffusion of ions, by growing or patterning the silicon oxide, or other isolation methods in semiconductor material with the primary function to limit the spread of the channel area or to prevent the formation of parasitic channels (inversion layers).", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "21019552", "revid": "12883001", "url": "https://en.wikipedia.org/wiki?curid=21019552", "title": "Plaster mold casting", "text": "Plaster mold casting is a metalworking casting process similar to sand casting except the molding material is plaster of Paris instead of sand. Like sand casting, plaster mold casting is an expendable mold process, however it can only be used with non-ferrous materials. It is used for castings as small as to as large as . Generally, the form takes less than a week to prepare. Production rates of 1–10 units/hr can be achieved with plaster molds.\nParts that are typically made by plaster casting are lock components, gears, valves, fittings, tooling, and ornaments.\nDetails.\nThe plaster is not pure plaster of Paris, but rather has additives to improve green strength, dry strength, permeability, and castability. For instance, talc or magnesium oxide are added to prevent cracking and reduce setting time; lime and cement limit expansion during baking; glass fibers increase strength; sand can be used as a filler. The ratio of ingredients is 70–80% gypsum and 20–30% additives.\nThe pattern is usually made from metal, however rubber molds may be used for complex geometry; these molds are called s. For example, if the casting includes reentrant angles or complex angular surfaces then the rubber is flexible enough to be removed, unlike metal. These molds are also inexpensive, reusable, more accurate than steel molds, fast to produce, and easy to change.\nTypical tolerances are for the first and 0.02 mm per additional centimeter (0.002 in per additional inch). A draft of 0.5 to 1 degree is required. Standard surface finishes that are attainable are 1.3 to 4 micrometers (50–125 μin).\nProcess.\nFirst, the parting line is determined - either simple two part or more complex (3 or more). A box is made around the pattern to hold the plaster. Then plaster is mixed and the pattern is sprayed with a thin film of parting compound also called a release agent to prevent the plaster from sticking to the pattern. The plaster is then poured over the pattern and the box holding the plaster and pattern is vibrated by mechanical means in order to fill all gaps and to release air bubbles. The plaster sets, usually in about 15 minutes, and the pattern is removed. The mold is then baked, between and , to remove any excess water. The dried mold is then assembled, preheated, and the metal poured. Finally, after the metal has solidified, the plaster is broken from the cast part. The mold is usually damaged from the metal so reusing is usually not done. Discarded plaster can be recycled by grinding but care must be used since silica dust causes lung damage.\nAdvantages and disadvantages.\nPlaster mold casting is used when an excellent surface finish and good dimensional accuracy is required. Because the plaster has a low thermal conductivity and heat capacity, the metal cools more slowly than in a sand mold, which allows the metal to fill thin cross-sections; the minimum possible cross-section is . This results in a near net shape casting, which can be a cost advantage on complex parts. It also produces minimal scrap material.\nThe major disadvantage of the process is that it can only be used with lower melting temperature non-ferrous materials, such as aluminium, magnesium, zinc and sometimes copper alloys. The most commonly used material is aluminium. The maximum working temperature of plaster is , so higher melting temperature materials would melt the plaster mold. Also, the sulfur in the gypsum reacts with iron, making it unsuitable for casting ferrous materials.\nAnother disadvantage is that its long cooling times restrict production volume. Onetime molds are often quenched in water but only after completing solidification so hot metal does not fly everywhere. Proper quenching can aid in mold removal and it makes some alloys stronger.\nPlaster is not as stable as sand, so it is dependent on several factors, including the consistency of the plaster composition, pouring procedures, and curing techniques. If these factors are not closely monitored the mold can be distorted, shrink upon drying, have a poor surface finish, or fail completely.", "Engineering,_Manufacturing": 1.0000058413, "qwen": "Yes"}
{"id": "21022342", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=21022342", "title": "Mechanical plating", "text": "Mechanical plating, also known as peen plating, mechanical deposition, or impact plating, is a plating process that imparts the coating by cold welding fine metal particles to a workpiece. Mechanical galvanization is the same process, but applies to coatings that are thicker than . It is commonly used to overcome hydrogen embrittlement problems. Commonly plated workpieces include nails, screws, nuts, washers, stampings, springs, clips, and sintered iron components.\nThe process involves tumbling the workpieces with a mixture of water, metal powder, media, and additives. Common coating materials are zinc, cadmium, tin, copper, and aluminium.\nInvented by the Tainton Company in the 1950s, it was further developed by the 3M company.\nProcess.\nThe process begins with a descaling and removing soil from the workpiece. This can be done in the tumbler or in a separate cleaning system. After cleaning, the parts are prepared by combining them with water, medium, and a surface conditioner. The surface conditioner lightly coats the workpiece in copper, while the medium removes any residual mill scale or oxides. Finally, accelerators, promoters and metal powder are added to the mix. The accelerators and promoters provide the proper chemical environment for the plating to occur, such as the maintenance of a pH level of 1 to 2 to prevent oxidation and promote adhesion. The medium that is already in the mixture cold welds the metal powder to the workpiece through impacts that are induced by the tumbling action of the tumbler. At this point the surface finish is typically matte to a semi-bright finish, however the finish can be improved with a water polish. The time required for the above process is approximately 50 minutes.\nFor some thinly coated workpieces a chromate passivation is necessary. Finally, the workpiece, whether passivated or not, is dried.\nThe medium material is usually soda lime glass or a ceramic. It is usually spherical in form, but angular shapes are also used. For plating, medium usage is usually 1 part medium for every workpiece, but for galvanization the ratio is 2:1. However, various sized media are used in each batch with a typical batch consisting of 50% sized beads, 25% sized beads, and 25% sized beads. The smaller media are omitted when the workpiece has a cavity that the medium can get caught in, such as a fastener's recessed head. Note that the medium is reused many times.\nThis process works better if the workpieces' surface finish is slightly rough.\nEquipment.\nThe most important piece of equipment in the process is the \"tumbler\". It is constructed of steel or stainless steel and lined with an acid and abrasion resistant material, such as neoprene, polypropylene, and polybutylene. The barrel sizes range from , however the working volume is only 25 to 35% of the total volume. For most plating applications the tumbler is rotated at 60 RPM, however it can vary. If the speed is too fast then lumpy deposits will form on the workpieces, but if the speed is too slow then the metal powder will not deposit onto the workpiece.\nThe \"separator\" separates the coated workpieces from the medium after coating. It can be as simple as a screen with water nozzles or as complicated as a vibratory system with magnetic separators. A \"medium handling machine\" then takes the separated medium and transports it to a storage tank for reuse.\nThe separated workpieces are then taken to a \"dryer\" to remove any moisture. Usually centrifugal dryers are used, however oven are used for larger parts or loads.\nAdvantages and disadvantages.\nThe greatest advantage of the process is its ability to overcome hydrogen embrittlement problems, which is important for workpieces that have a hardness greater than HRC 40. Note that there still is some embrittlement of the workpiece. While this process does not cause problems with hydrogen embrittlement, and electroplating does, it still offers equivalent corrosion protection. There is a great cost savings in using mechanical plating over electroplating on hardened workpieces, because the electroplating processes requires a pre- and post-plating operation to overcome hydrogen embrittlement problems. Moreover, because mechanical plating occurs at room temperature there is no tempering of hardened workpieces.\nAnother advantage is that mechanical plating evenly coats all surfaces and features, unlike electroplating which has issues plating recesses. Mechanical plating can evenly coat up to 75 μm thick. For thicker plating mechanical plating is especially cost advantageous versus electroplating, because the cycle time does not increase much for the thicker plating, unlike electroplating.\nOne of the disadvantages is the processes size limitations. Workpieces heavier than can be damaged by the process, while flat lightweight workpieces tend to stick together so they are not properly plated.", "Engineering,_Manufacturing": 0.9999978542, "qwen": "Yes"}
{"id": "9430259", "revid": "1128788884", "url": "https://en.wikipedia.org/wiki?curid=9430259", "title": "START Lab", "text": "START Lab Inc. (株式会社スタート ・ ラボ; \"Sony Taiyo Yuden Advanced Recording Technology Laboratory\") is a joint venture of Sony Corporation and Taiyo Yuden Co., Ltd. The headquarters are in Chiyoda, Tokyo.\nSTART Lab, founded in June 1989, was active in the optical media business. Initially intended to produce small-scale runs of CDs for business customers on the basis of newly developed CD-R technology, it pioneered the sale of CD-R media to consumers. The current president is Masanori Kimizuka. 50.1% of START Lab is owned by Sony, 49.9% is owned by Taiyo Yuden.\nSTART Lab ceased operations in March 2016 after parent company Taiyo Yuden ended production of storage media.\nWell-known product lines included the That's consumer media, the That's CD-R/DVD-R for master product line, and the CD/DVD error checkers (ES-50, ES-70, ES-1000 rebranded Almedio model).", "Engineering,_Manufacturing": 0.9998006225, "qwen": "Yes"}
{"id": "20560455", "revid": "9784415", "url": "https://en.wikipedia.org/wiki?curid=20560455", "title": "Velocette KTT Mk VIII", "text": "The Velocette KTT Mk VIII is a British racing motorcycle made by Veloce, Ltd. who built motorcycles named the Velocette. The Mk VIII KTT was ultimate development of their \"K\" series of overhead-camshaft 350cc machines introduced in 1925, and the \"TT\" designation indicated a production racing motorcycle, and a near replica of the factory race team machines. Production continued until 1950.\nDevelopment.\nThe final development of the Velocette KTT, the Mk VIII KTT was introduced in 1938 at that year's Earls Court Show, and was the first motorcycle to use the now-conventional swinging-arm rear fork with a shock absorber unit (in this case, an oleo-pneumatic unit built by the Oleo Strut Co. of England). The rear suspension system was designed by Veloce development engineer Harold Willis, and was inspired by the Oleo strut landing gear on the DeHavilland Hornet he borrowed at the Midland Aero Club, while his beloved DeHavilland 'Moth' was undergoing repair. Contact with the Oleo company led to several pairs of air shocks built for Veloce in 1936, for which the factory's racing rigid-frame racers (similar to the Mark VII KTT) were adapted with a swinging-fork rear end and bolt-on subframe for the seat. The experimental first swinging-arms used an adapted steering head lug turned sideways, with the cup-and-cone bearings retained. Production Mark VIII KTTs used a more conventional bronze bush and trunnion shaft pivot for the one-piece rear fork. The first experimental swing-arm machines were raced by the factory in the 1937 season, and introduced as the Mark VIII KTT the next year, for sale to the public.\nThe Mark VIII KTT was offered from 1938 - 1950, after which Veloce closed its racing department.", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "20563242", "revid": "8766034", "url": "https://en.wikipedia.org/wiki?curid=20563242", "title": "Interfering thread nut", "text": "An interfering thread nut is a type of locknut that has an undersized root diameter. This creates an interference between the nut and the fastener, plastically deforming the threads on the fastener. Due to this deformation they are usually only used on permanent or semi-permanent installations.\nA variation of this nut is the tapered thread nut. It utilizes a tapered thread to achieve the interference. The nut goes on easily, because the thread diameter starts at a standard size; as the nut is further threaded on it begins to lock, much like a distorted thread locknut.", "Engineering,_Manufacturing": 0.9999934435, "qwen": "Yes"}
{"id": "20569256", "revid": "1588193", "url": "https://en.wikipedia.org/wiki?curid=20569256", "title": "Swage nut", "text": "A swage nut or self-clinching nut is a type of nut or threaded insert that is used on sheet metal. \nIt permanently anchors itself to the sheet metal by swaging the surrounding material. Generally, the swage nut is made of a hard metal such as stainless steel, which is inserted into a pre-drilled hole in a softer ductile material such as aluminum. The inserted shank has three diameters: a main shaft which fits the hole closely, a thin smaller-diameter undercut, and a larger-diameter serrated clinching ring. Forcing the clinching ring into softer material, with an arbor press or by tightening a screw through the hole, causes it to plastically deform (swage) into the annular recess in the shank. This locks the nut into the hole. The knurling on the clinching ring is not necessary for this step, but prevents the nut from rotating after installation.\nThis is a popular method for adding strong, load-bearing threads to a relatively thin piece of soft sheet metal.\nSelf-clinching nuts are described in National Aerospace Standard NASM45938 which supersedes military specification MIL-N-45938\nHistory.\nAlbert Spokes filed for a U.S. patent on the swage nut in early 1958. The swage nut is descended from an older idea, the clinch nut. Clinch nuts incorporate a tubular shaft that fits through the part to be attached and is clinched or riveted in place from the opposite side.", "Engineering,_Manufacturing": 0.9999960661, "qwen": "Yes"}
{"id": "20571411", "revid": "8390765", "url": "https://en.wikipedia.org/wiki?curid=20571411", "title": "Clip-on nut", "text": "A clip-on nut, also known as a sheet metal nut or a speed nut (but this is ambiguous, see speed nut), is a type of nut designed to be clipped to sheet metal. It is a type of captive nut commonly made as a cage nut. \nTypes.\nThey come in many forms based upon: where they clip on, shape, and type of thread. Each clip-on nut is designed for only a small range of sheet metal gauges (thicknesses). They are usually made from spring steel.\nG-nut.\nA G-nut, or G-style nut, is shaped like a \"G\" and clips to the edge of a sheet metal object. It is different from all of the other types in that it is meant to clip over a small flange on the edge of the sheet metal. The threads are from an integrated nut that has a special boss to sit in a hole in the sheet metal.\nJ-nut.\nA J-nut is a nut that clips to the edge of the sheet metal. It is named after the way it is shaped; the thread is on the long side of the \"J\". The thread may either be of a speed nut form or have an integrated hex or square nut. Due to the short retaining leg the nut is allowed to float more, which can help with misalignment, but the nut is free to un-clip from the sheet metal as well.\nS-nut.\nAn S-nut, or S-style nut, is shaped like an \"S\". It is designed to clip on the edge of a sheet metal object. The threads are provided by an integrated nut.\nSquare style.\nA square style clip-on nut does not clip onto the edge of the sheet metal, but rather the edges of a square hole or slot. It is a square nut that has a sheet metal retainer that protrudes down two sides of the nut. These legs are formed to have lips that grab onto the sheet metal object. Prior to tightening the nut, it can float in the hole or slot, but when the nut is tightened it presses the lips of the retainer out and anchors itself in place.\nU-nut.\nA U-nut is very similar to a J-nut except that both legs are the same length. Because of this a retaining clip is usually formed on the leg without the threads. This helps keep the nut in place while not screwed down. The thread may be of a speed nut style, integrated nut, or have an extruded portion that is tapped. There are \"standard\" and \"wide-panel\" versions; the standard version has a solid hinge section, whereas the wide-panel version has a longer hinge with the center section cut-away to allow for easier installation.", "Engineering,_Manufacturing": 0.9996907711, "qwen": "Yes"}
{"id": "20575536", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=20575536", "title": "Reliability (semiconductor)", "text": "Reliability of semiconductor devices can be summarized as follows:\nDesign factors affecting semiconductor reliability include: voltage, power, and current derating; metastability; logic timing margins (logic simulation); timing analysis; temperature derating; and process control.\nMethods of improvement.\nReliability of semiconductors is kept high through several methods. Cleanrooms control impurities,\nprocess control controls processing, and burn-in (short term operation at extremes) and probe and test reduce escapes. Probe (wafer prober) tests the semiconductor die, prior to packaging, via micro-probes connected to test equipment. Final test tests the packaged device, often pre-, and post burn-in for a set of parameters that assure operation. Process and design weaknesses are identified by applying a set of stress tests in the qualification phase of the semiconductors before their market introduction e. g. according to the AEC Q100 and Q101 stress qualifications. Parts Average Testing is a statistical method for recognizing and quarantining semiconductor die that have a higher probability of reliability failures. This technique identifies characteristics that are within specification but outside of a normal distribution for that population as at-risk outliers not suitable for high reliability applications. Tester-based Parts Average Testing varieties include Parametric Parts Average Testing (P-PAT) and Geographical Parts Average Testing (G-PAT), among others. Inline Parts Average Testing (I-PAT) uses data from production process control inspection and metrology to perform the outlier recognition function.\nBond strength measurement is performed in two basic types: pull testing and shear testing. Both can be done destructively, which is more common, or non destructively. Non destructive tests are normally used when extreme reliability is required such as in military or aerospace applications.\nFailure mechanisms.\nFailure mechanisms of electronic semiconductor devices fall in the following categories", "Engineering,_Manufacturing": 0.9999984503, "qwen": "Yes"}
{"id": "34622442", "revid": "44426166", "url": "https://en.wikipedia.org/wiki?curid=34622442", "title": "Plastic forming machine", "text": "Plastic forming machines, or plastic molding machines, were developed on the basis of rubber machinery and metal die-casting machines. After the inception of the polymer injection molding process in the 1870s, plastic-forming machines were rapidly developed up until the 1930s. With the gradual commercialization of plastic molding equipment, injection molding and extrusion molding became the most common industrialized processes. Blow molding is the third-largest plastic molding method after the injection molding and extrusion blow molding methods.\nTypes of plastic forming machine.\nPlastic injection molding machine.\nA plastic injection molding machine injects melted plastic into a mold to make solid plastic parts.\nPlastic extrusion machine.\nA plastic extrusion machine extrudes plastic in a continuous profile. The main machine is usually called the host, and its accompanying equipment are called the plastic auxiliary equipment. Plastic extruders can make plastic film/wrapping, packing tape, corrugated sheets, plastic lumber, pipes, tubes, insulated wire, monofilament and nets.\nPlastic blow molding machine.\nA plastic blow molding machine inflates a preform or parison inside of a mold to form hollow parts.\nThermoforming.\nThermoforming is a manufacturing process where a plastic sheet is heated to a pliable forming temperature, and stamped to a specific shape in a 2-part mold. Or a vacuum can be used to pull the plastic sheet onto the mold in a simplified process known as vacuum forming. The excess material is trimmed off and recycled.\nRotational molding.\nRotational molding involves a heated hollow mold that is filled with a charge or shot weight of material. It is then slowly rotated (usually around two perpendicular axes), causing the softened material to disperse and stick to the walls of the mold forming a hollow part. In order to form an even thickness throughout the part, the mold rotates at all times during the heating phase, and then continues to rotate during the cooling phase to avoid sagging or deformation. Rotocasting is a variant of the process that uses self-curing or UV-curable resins (as opposed to thermoplastics) in an unheated mold.\nSee also.\nMold-A-Rama", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "18898191", "revid": "14965160", "url": "https://en.wikipedia.org/wiki?curid=18898191", "title": "Boutique manufacturing", "text": " \nBoutique manufacturing is a method used for the custom production of certain products in limited quantities by hand or with a restricted level of automation. Products produced this way often include ceramics, furniture, amplifiers, yachts, boats, leather goods or watches and jewellery among others. In industrial countries, boutique manufacturing is being selected generally for high class goods in upper price levels and only for single products or small batches.\nBenefits and disadvantages.\nThe key advantages of boutique manufacturing in comparison to traditional factory manufacturing with batch fabrication, large or mass production are as follows:\nConsequently, boutique manufacturing closes the gap between piece production and small batch/low volume production. The workflow organization of a boutique manufacturing entity can be a mixture of both – elements of jobbing or batch production, however involving higher standardization than the first one. Often boutique manufacturing workshop and factories are organized with single workplaces or production cells carrying out a number of subsequent production steps until completion of certain components or even the whole product. Flexibility and variety of products being able to produce in the entity therefore are much higher than with the more standardized method batch production. \nHowever, with this method, manufacturing of larger quantities of unified products is not possible at reasonable costs. Serial fabrication or large production of goods then would be suitable alternative production methods involving higher grades of automation and standardization.", "Engineering,_Manufacturing": 1.0000085831, "qwen": "Yes"}
{"id": "2171341", "revid": "4743453", "url": "https://en.wikipedia.org/wiki?curid=2171341", "title": "Just in case", "text": "Just-in-case manufacturing (JIC) is a term sometimes applied to traditional manufacturing systems used before the influence of modern technologies and newer transportation infrastructures. It is the contrary in many ways to the recently evolved Just In Time manufacturing system.\nOperation.\nIn JIC, manufacturers need to maintain large inventories of supplies, parts, warehousing resources, and extra workers to meet production contingencies. These contingencies, more common in less industrialized countries, can be poor transportation infrastructure, poor quality control, vulnerability to other suppliers' production problems, and natural disasters. These supply-chain instabilities could lead to costly production inefficiencies therefore a manufacturer may maintain and pay for excess inventory and backups of \"fragile\" production stages which could get out of sync, cause production shutdowns, or create supply-chain delays for other manufacturers. In JIC, manufacturers reorder stock before it reaches the buffer level or minimum level to allow themselves to have inventories to be sold while the suppliers are supplying the goods. This time range from the time the firm reorders the stock to the time the supplier provides the new stock is known as lead time. Thus a JIC inventory system tries to keep a minimum level of inventories just in case of emergencies, hence the name \"Just In Case\".\nOne major reason for practicing a more costly JIC system are the potential losses paid (i.e. permanent loss of major customers, loss of suppliers, supply-chain collapse) if supply-chain shocks occur on several occasions. If the JIT response contingencies are too slow or fail to keep production flowing additional costs may be incurred. Under these circumstances the additional costs due to maintaining extra storage, resources, and system resiliency may potentially be more cost effective than using a more efficient JIT system. A JIC examples of buyers would be the military or hospitals who need to maintain large inventories because waiting for JIT producers to ramp up production for needed supplies may result in losses (i.e. wars, lives).", "Engineering,_Manufacturing": 0.9994348288, "qwen": "Yes"}
{"id": "3365329", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=3365329", "title": "Design for logistics", "text": "Design for logistics is a series of concepts in the field of supply chain management involving product and design approaches that help to control logistics costs and increase customer service level. These concepts were introduced by Professor Hau Lee of Stanford University, and have the three key components: Economic packaging and transportation, Concurrent and parallel processing, and Standardization.\nEconomic packaging and transportation.\nThere are three levels, moving from operational, to tactical and finally strategic.\nConcurrent and parallel processing.\nModify the manufacturing process so that steps that were previously performed in a sequence can be completed at the same time. This will help reduce manufacturing lead time, lower inventory costs through improved forecasting, and reduce safety stock requirements, among other benefits.\nStandardization.\nThe idea of standardization is to exploit economies of scale, and doing things once that can be applied many times. Standardization can be done through:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "3365401", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=3365401", "title": "Delayed differentiation", "text": "Delayed differentiation or Postponement is a concept in supply chain management where the manufacturing process starts by making a generic or family product that is later differentiated into a specific end-product. This is a widely used method, especially in industries with high demand uncertainty, and can be effectively used to address the final demand even if forecasts cannot be improved.\nAn example would be Benetton and their knitted sweaters that are initially all white, and then dyed into different colors only when the season/customer color preference/demand is known. It is usually necessary to redesign the product specifically for delayed differentiation, and resequencing to modify the order of production manufacturing steps.\nSee also.\nTypically all paint companies were burdened with the problem of having more than 200 shades, each available in more than 5 container sizes, making more than 1000 Stock keeping Units (SKUs). The cost of keeping so many final products was almost killing the business. \nPaint companies changed their process to make white paint and the dyes of three basic colours. The final mixing was done by a machine at the retail end. This minimised the inventory kept by the retailer whilst improving customer service by giving the customer a choice of millions of shades in the exact quantity required.", "Engineering,_Manufacturing": 0.9997307658, "qwen": "Yes"}
{"id": "3367341", "revid": "5229428", "url": "https://en.wikipedia.org/wiki?curid=3367341", "title": "Magnetorheological finishing", "text": "Magnetorheological finishing (MRF) is a precision surface finishing technology. Optical surfaces are polished in a computer-controlled magnetorheological (MR) finishing slurry. Unlike conventional rigid lap polishing, the MR fluid's shape and stiffness can be magnetically manipulated and controlled in real time. The optic's final surface form and finishing results are predicted through the use of computer algorithms.\nLiterature.\n W.I. Kordonski (2014). \"Magnetorheological Fluid-Based High Precision Finishing Technology.\" Magnetorheology: Advances and Applications, Norman M. Wereley, Ed., RSC Smart Materials, Cambridge, UK, Chapter 11, 261–277. \nDOI:10.1039/9781849737548-00261\n S.D. Jacobs, W.I. Kordonski, I.V. Prokhorov, D. Golini, G.R. Gorodkin, T.D. Strafford (2002). \"Deterministic Magnetorheological Finishing.\" US Patent: US5449313A\n Shorey et al. \"Experiments and Observations Regarding the Mechanisms of Glass Removal in Magnetorheological Finishing\", abstract and full text (pdf)\n Chunlin Miao, et al., \"Shear stress in magnetorheological finishing for glasses,\" Applied Optics 48, 2585-2594 (2009)\n Chunlin Miao, et al., \"Process parameter effects on material removal in magnetorheological finishing of borosilicate glass,\" Applied Optics 49, 1951-1963 (2010)", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "3370630", "revid": "35932881", "url": "https://en.wikipedia.org/wiki?curid=3370630", "title": "Crescent Machine Company", "text": "Crescent Machine Company was founded in Leetonia, Ohio in 1893. It manufactured a line of industrial woodworking machinery, particularly band saws. In 1940, it was bought by Pittsburgh Equitable Meter and Manufacturing Company, which became the Rockwell Manufacturing Company in 1946.\nThird party website: http://wiki.vintagemachinery.org/CrescentHistory.ashx\nReferences", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "22563140", "revid": "43484343", "url": "https://en.wikipedia.org/wiki?curid=22563140", "title": "Grupo Industrial Ramirez", "text": "Grupo Industrial Ramirez was the first Mexican automotive company and also the first Mexican company to ever produce pickup trucks and vans.\nHistory.\nThe company was started in 1946 by Gregorio Ramirez Gonzalez, with a small shop to reconstruct dry van trailers. It later grew into a larger corporation with a full list of products in which he invited his brothers to participate.\nTrailers de Monterrey.\nThe flagship of the Corporation was Trailers de Monterrey, which began as a dry van fabricator and grew into making trucks and buses under the Ramírez and Sultana brands.\nIndustria Automotriz.\nIn 1957 Industria Automotriz, S.A. was established, manufacturing rims, stampings, assembly and sub assembly.\nBerg de Mexico.\nIn 1964 Berg de Mexico, S.A was established to produce air brakes for heavy vehicles. In 1982 it was renamed to Industrias Vortec, S.A.\nHolding company.\nBy 1978 Grupo Industrial Ramirez was established as a holding company, controlling all of the group's interests.", "Engineering,_Manufacturing": 0.9992400408, "qwen": "Yes"}
{"id": "22577605", "revid": "1161447328", "url": "https://en.wikipedia.org/wiki?curid=22577605", "title": "Flatness (manufacturing)", "text": "In manufacturing and mechanical engineering, flatness is an important geometric condition for workpieces and tools. Flatness is the condition of a surface or derived median plane having all elements in one plane.\nIn the manufacture of precision parts and assemblies, especially where parts will be required to be connected across a surface area in an air-tight or liquid-tight manner, flatness is a critical quality of the manufactured surfaces. Such surfaces are usually machined or ground to achieve the required degree of flatness. High-definition metrology, such as digital holographic interferometry, of such a surface to confirm and ensure that the required degree of flatness has been achieved is a key step in such manufacturing processes. Flatness may be defined in terms of least squares fit to a plane (\"statistical flatness\") or worst-case (the distance between the two closest parallel planes within). It can be specified for a given area and/or over an entire surface. \nTwo parts that are flat to about 1 helium light band (HLB) can be \"wrung\" together, which means they will cling to each other when placed in contact. This phenomenon is commonly used with gauge blocks.\nGeometric dimensioning and tolerancing has provided geometrically defined, quantitative ways of defining flatness operationally. \nHistory.\nJoseph Whitworth popularized the first practical method of making accurate flat surfaces during the 1830s, using engineer's blue and scraping techniques on three trial surfaces, in what is known as Whitworth's three plates method. By testing all three in pairs against each other, it is ensured that the surfaces become flat. Using two surfaces would result in a concave surface and a convex surface. Eventually a point is reached when many points of contact are visible within each square inch, at which time the three surfaces are uniformly flat to a very close tolerance.\nUp until his introduction of the scraping technique, the same three plate method was employed using polishing techniques, giving less accurate results. This led to an explosion of development of precision instruments using these flat surface generation techniques as a basis for further construction of precise shapes.", "Engineering,_Manufacturing": 0.9997419715, "qwen": "Yes"}
{"id": "53572933", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=53572933", "title": "Boron nitride aerogel", "text": "Boron nitride aerogel is an aerogel made of highly porous boron nitride (BN). It typically consists of a mixture of deformed boron nitride nanotubes and nanosheets. It can have a density as low as 0.6 mg/cm3 and a specific surface area as high as 1050 m2/g, and therefore has potential applications as an absorbent, catalyst support and gas storage medium. BN aerogels are highly hydrophobic and can absorb up to 160 times their mass in oil. They are resistant to oxidation in air at temperatures up to 1200 °C, and hence can be reused after the absorbed oil is burned out by flame. BN aerogels can be prepared by template-assisted chemical vapor deposition at a temperature ~900 °C using borazine as the feed gas. Alternatively it can be produced by ball milling h-BN powder, ultrasonically dispersing it in water, and freeze-drying the dispersion.", "Engineering,_Manufacturing": 0.9992601275, "qwen": "Yes"}
{"id": "32704529", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=32704529", "title": "Ping test (engineering)", "text": "A ping test is a physical test to determine the natural frequency of an object or assembly. The test consists of instrumenting the object or assembly with measuring devices and then tapping it with another metallic object (usually a hammer.) The undamped system will then vibrate at its natural frequency. The ping test is used on assemblies and objects where vibration can be an issue.", "Engineering,_Manufacturing": 0.9999849796, "qwen": "Yes"}
{"id": "8054686", "revid": "33285776", "url": "https://en.wikipedia.org/wiki?curid=8054686", "title": "Printed electronics", "text": "Printed electronics is a set of printing methods used to create electrical devices on various substrates. Printing typically uses common printing equipment suitable for defining patterns on material, such as screen printing, flexography, gravure, offset lithography, and inkjet. By electronic-industry standards, these are low-cost processes. Electrically functional electronic or optical inks are deposited on the substrate, creating active or passive devices, such as thin film transistors; capacitors; coils; resistors. Some researchers expect printed electronics to facilitate widespread, very low-cost, low-performance electronics for applications such as flexible displays, smart labels, decorative and animated posters, and active clothing that do not require high performance.\nThe term \"printed electronics\" is often related to organic electronics or plastic electronics, in which one or more inks are composed of carbon-based compounds. These other terms refer to the ink material, which can be deposited by solution-based, vacuum-based, or other processes. Printed electronics, in contrast, specifies the process, and, subject to the specific requirements of the printing process selected, can utilize any solution-based material. This includes organic semiconductors, inorganic semiconductors, metallic conductors, nanoparticles, and nanotubes.\nFor the preparation of printed electronics nearly all industrial printing methods are employed. Similar to conventional printing, printed electronics applies ink layers one atop another. So the coherent development of printing methods and ink materials are the field's essential tasks.\nThe most important benefit of printing is low-cost volume fabrication. The lower cost enables use in more applications. An example is RFID-systems, which enable contactless identification in trade and transport. In some domains, such as light-emitting diodes printing does not impact performance. Printing on flexible substrates allows electronics to be placed on curved surfaces, for example: printing solar cells on vehicle roofs. More typically, conventional semiconductors justify their much higher costs by providing much higher performance.\nResolution, registration, thickness, holes, materials.\nThe maximum required resolution of structures in conventional printing is determined by the human eye. Feature sizes smaller than approximately 20 µm cannot be distinguished by the human eye and consequently exceed the capabilities of conventional printing processes. In contrast, higher resolution and smaller structures are necessary in most electronics printing, because they directly affect circuit density and functionality (especially transistors). A similar requirement holds for the precision with which layers are printed on top of each other (layer to layer registration).\nControl of thickness, holes, and material compatibility (wetting, adhesion, solubility) are essential, but matter in conventional printing only if the eye can detect them. Conversely, the visual impression is irrelevant for printed electronics.\nPrinting technologies.\nThe attraction of printing technology for the fabrication of electronics mainly results from the possibility of preparing stacks of micro-structured layers (and thereby thin-film devices) in a much simpler and cost-effective way compared to conventional electronics. Also, the ability to implement new or improved functionalities (e.g. mechanical flexibility) plays a role. The selection of the printing method used is determined by requirements concerning printed layers, by the properties of printed materials as well as economic and technical considerations of the final printed products.\nPrinting technologies divide between sheet-based and roll-to-roll-based approaches. Sheet-based inkjet and screen printing are best for low-volume, high-precision work. Gravure, offset and flexographic printing are more common for high-volume production, such as solar cells, reaching 10,000 square meters per hour (m2/h). While offset and flexographic printing are mainly used for inorganic and organic conductors (the latter also for dielectrics), gravure printing is especially suitable for quality-sensitive layers like organic semiconductors and semiconductor/dielectric-interfaces in transistors, due to high layer quality. If high resolution is needed, gravure is also suitable for inorganic and organic conductors. Organic field-effect transistors and integrated circuits can be prepared completely by means of mass-printing methods.\nInkjet printing.\nInkjets are flexible and versatile, and can be set up with relatively low effort. However, inkjets offer lower throughput of around 100 m2/h and lower resolution (ca. 50 µm). It is well suited for low-viscosity, soluble materials like organic semiconductors. With high-viscosity materials, like organic dielectrics, and dispersed particles, like inorganic metal inks, difficulties due to nozzle clogging occur. Because ink is deposited via droplets, thickness and dispersion homogeneity is reduced. Using many nozzles simultaneously and pre-structuring the substrate allows improvements in productivity and resolution, respectively. However, in the latter case non-printing methods must be employed for the actual patterning step. Inkjet printing is preferable for organic semiconductors in organic field-effect transistors (OFETs) and organic light-emitting diodes (OLEDs), but also OFETs completely prepared by this method have been demonstrated. Frontplanes and backplanes of OLED-displays, integrated circuits, organic photovoltaic cells (OPVCs) and other devices can be prepared with inkjets.\nScreen printing.\nScreen printing is appropriate for fabricating electrics and electronics due to its ability to produce patterned, thick layers from paste-like materials. This method can produce conducting lines from inorganic materials (e.g. for circuit boards and antennas), but also insulating and passivating layers, whereby layer thickness is more important than high resolution. Its 50 m2/h throughput and 100 µm resolution are similar to inkjets. This versatile and comparatively simple method is used mainly for conductive and dielectric layers, but also organic semiconductors, e.g. for OPVCs, and even complete OFETs can be printed.\nAerosol jet printing.\nAerosol Jet Printing (also known as Maskless Mesoscale Materials Deposition or M3D) is another material deposition technology for printed electronics. The Aerosol Jet process begins with atomization of an ink, via ultrasonic or pneumatic means, producing droplets on the order of one to two micrometers in diameter. The droplets then flow through a virtual impactor which deflects the droplets having lower momentum away from the stream. This step helps maintaining a tight droplet size distribution. The droplets are entrained in a gas stream and delivered to the print head. Here, an annular flow of clean gas is introduced around the aerosol stream to focus the droplets into a tightly collimated beam of material. The combined gas streams exit the print head through a converging nozzle that compresses the aerosol stream to a diameter as small as 10 µm. The jet of droplets exits the print head at high velocity (~50 meters/second) and impinges upon the substrate.\nElectrical interconnects, passive and active components are formed by moving the print head, equipped with a mechanical stop/start shutter, relative to the substrate. The resulting patterns can have features ranging from 10 µm wide, with layer thicknesses from tens of nanometers to >10 µm. A wide nozzle print head enables efficient patterning of millimeter size electronic features and surface coating applications. All printing occurs without the use of vacuum or pressure chambers. The high exit velocity of the jet enables a relatively large separation between the print head and the substrate, typically 2–5 mm. The droplets remain tightly focused over this distance, resulting in the ability to print conformal patterns over three dimensional substrates.\nDespite the high velocity, the printing process is gentle; substrate damage does not occur and there is generally minimal splatter or overspray from the droplets. Once patterning is complete, the printed ink typically requires post treatment to attain final electrical and mechanical properties. Post-treatment is driven more by the specific ink and substrate combination than by the printing process. A wide range of materials has been successfully deposited with the Aerosol Jet process, including diluted thick film pastes, conducting polymer inks, thermosetting polymers such as UV-curable epoxies, and solvent-based polymers like polyurethane and polyimide, and biologic materials.\nRecently, printing paper was proposed to be used as the substrate of the printing. Highly conductive (close to bulk copper) and high-resolution traces can be printed on foldable and available office printing papers, with 80°Celsius curing temperature and 40 minutes of curing time.\nEvaporation printing.\nEvaporation printing uses a combination of high precision screen printing with material vaporization to print features to 5 µm. This method uses techniques such as thermal, e-beam, sputter and other traditional production technologies to deposit materials through a high precision shadow mask (or stencil) that is registered to the substrate to better than 1 µm. By layering different mask designs and/or adjusting materials, reliable, cost-effective circuits can be built additively, without the use of photo-lithography.\nOther methods.\nOther methods with similarities to printing, among them microcontact printing and nano-imprint lithography are of interest. Here, µm- and nm-sized layers, respectively, are prepared by methods similar to stamping with soft and hard forms, respectively. Often the actual structures are prepared subtractively, e.g. by deposition of etch masks or by lift-off processes. For example, electrodes for OFETs can be prepared. Sporadically pad printing is used in a similar manner. Occasionally so-called transfer methods, where solid layers are transferred from a carrier to the substrate, are considered printed electronics. Electrophotography is currently not used in printed electronics.\nMaterials.\nBoth organic and inorganic materials are used for printed electronics. Ink materials must be available in liquid form, for solution, dispersion or suspension. They must function as conductors, semiconductors, dielectrics, or insulators. Material costs must be fit for the application.\nElectronic functionality and printability can interfere with each other, mandating careful optimization. For example, a higher molecular weight in polymers enhances conductivity, but diminishes solubility. For printing, viscosity, surface tension and solid content must be tightly controlled. Cross-layer interactions such as wetting, adhesion, and solubility as well as post-deposition drying procedures affect the outcome. Additives often used in conventional printing inks are unavailable, because they often defeat electronic functionality.\nMaterial properties largely determine the differences between printed and conventional electronics. Printable materials provide decisive advantages beside printability, such as mechanical flexibility and functional adjustment by chemical modification (e.g. light color in OLEDs).\nPrinted conductors offer lower conductivity and charge carrier mobility.\nWith a few exceptions, inorganic ink materials are dispersions of metallic or semiconducting micro- and nano-particles. Semiconducting nanoparticles used include silicon and oxide semiconductors. Silicon is also printed as an organic precursor which is then converted by pyrolisis and annealing into crystalline silicon.\nPMOS but not CMOS is possible in printed electronics.\nOrganic materials.\nOrganic printed electronics integrates knowledge and developments from printing, electronics, chemistry, and materials science, especially from organic and polymer chemistry. Organic materials in part differ from conventional electronics in terms of structure, operation and functionality, which influences device and circuit design and optimization as well as fabrication method.\nThe discovery of conjugated polymers and their development into soluble materials provided the first organic ink materials. Materials from this class of polymers variously possess conducting, semiconducting, electroluminescent, photovoltaic and other properties. Other polymers are used mostly as insulators and dielectrics.\nIn most organic materials, hole transport is favored over electron transport. Recent studies indicate that this is a specific feature of organic semiconductor/dielectric-interfaces, which play a major role in OFETs. Therefore, p-type devices should dominate over n-type devices. Durability (resistance to dispersion) and lifetime is less than conventional materials.\nOrganic semiconductors include the conductive polymers poly(3,4-ethylene dioxitiophene), doped with poly(styrene sulfonate),  and poly(aniline) (PANI). Both polymers are commercially available in different formulations and have been printed using inkjet, screen and offset printing or screen, flexo and gravure printing, respectively.\nPolymer semiconductors are processed using inkjet printing, such as poly(thiopene)s like poly(3-hexylthiophene) (P3HT) and poly(9,9-dioctylfluorene co-bithiophen) (F8T2). The latter material has also been gravure printed. Different electroluminescent polymers are used with inkjet printing, as well as active materials for photovoltaics (e.g. blends of P3HT with fullerene derivatives), which in part also can be deposited using screen printing (e.g. blends of poly(phenylene vinylene) with fullerene derivatives).\nPrintable organic and inorganic insulators and dielectrics exist, which can be processed with different printing methods.\nInorganic materials.\nInorganic electronics provides highly ordered layers and interfaces that organic and polymer materials cannot provide.\nSilver nanoparticles are used with flexo, offset and inkjet. Gold particles are used with inkjet.\nA.C. electroluminescent (EL) multi-color displays can cover many tens of square meters, or be incorporated in watch faces and instrument displays. They involve six to eight printed inorganic layers, including a copper doped phosphor, on a plastic film substrate.\nCIGS cells can be printed directly onto molybdenum coated glass sheets.\nA printed gallium arsenide germanium solar cell demonstrated 40.7% conversion efficiency, eight times that of the best organic cells, approaching the best performance of crystalline silicon.\nSubstrates.\nPrinted electronics allows the use of flexible substrates, which lowers production costs and allows fabrication of mechanically flexible circuits. While inkjet and screen printing typically imprint rigid substrates like glass and silicon, mass-printing methods nearly exclusively use flexible foil and paper. Poly(ethylene terephthalate)-foil (PET) is a common choice, due to its low cost and moderately high temperature stability. Poly(ethylene naphthalate)- (PEN) and poly(imide)-foil (PI) are higher performance, higher cost alternatives. Paper's low costs and manifold applications make it an attractive substrate, however, its high roughness and high wettability have traditionally made it problematic for electronics. This is an active research area, however, and print-compatible metal deposition techniques have been demonstrated that adapt to the rough 3D surface geometry of paper.\nOther important substrate criteria are low roughness and suitable wet-ability, which can be tuned pre-treatment by use of coating or Corona discharge. In contrast to conventional printing, high absorbency is usually disadvantageous.\nHistory.\nAlbert Hanson, a German by birth, is credited to have introduced the concept of printed electronics. in 1903 he filled a patent for “Printed Wires,” and thus printed electronics were born. Hanson proposed forming a Printed Circuit Board pattern on copper foil through cutting or stamping. The drawn elements were glued to the dielectric, in this case, paraffined paper. The first printed circuit was produced in 1936 by Paul Eisler, and that process was used for large-scale production of radios by the USA during World War II. Printed circuit technology was released for commercial use in the US in 1948 (Printed Circuits Handbook, 1995). In the over a half-century since its inception, printed electronics has evolved from the production of printed circuit boards (PCBs), through the everyday use of membrane switches, to today's RFID, photovoltaic and electroluminescent technologies. Today it is nearly impossible to look around a modern American household and not see devices that either uses printed electronic components or that are the direct result of printed electronic technologies. Widespread production of printed electronics for household use began in the 1960s when the Printed Circuit Board became the foundation for all consumer electronics. Since then printed electronics have become a cornerstone in many new commercial products.\nThe biggest trend in recent history when it comes to printed electronics is the widespread use of them in solar cells. In 2011, researchers from MIT created a flexible solar cell by inkjet printing on normal paper. In 2018, researchers at Rice University have developed organic solar cells which can be painted or printed onto surfaces. These solar cells have been shown to max out at fifteen percent efficiency. Konarka Technologies, now a defunct company in the US, was the pioneering company in producing inkjet solar cells. Today there are more than fifty companies across a diverse number of countries that are producing printed solar cells.\nWhile printed electronics have been around since the 1960s, they are predicted to have a major boom in total revenue. As of 2011, the total printed electronic revenue was reported to be at $12.385 (billion). A report by IDTechEx predicts the PE market will reach $330 (billion) in 2027. A big reason for this increase in revenue is because of the incorporation of printed electronic into cellphones. Nokia was one of the companies that pioneered the idea of creating a “Morph” phone using printed electronics. Since then, Apple has implemented this technology into their iPhone XS, XS Max, and XR devices. Printed electronics can be used to make all of the following components of a cellphone: 3D main antenna, GPS antenna, energy storage, 3D interconnections, multi-layer PCB, edge circuits, ITO jumpers, hermetic seals, LED packaging, and tactile feedback.\nWith the revolutionary discoveries and advantages that printed electronic gives to companies many large companies have made recent investments into this technology. In 2007, Soligie Inc. and Thinfilm Electronics entered into an agreement to combine IPs for soluble memory materials and functional materials printing to develop printed memory in commercial volumes. LG announce significant investment, potentially $8.71 billion in OLEDs on Plastic. Sharp (Foxconn) will invest $570m in pilot line for OLED displays. BOE announce potential $6.8 billion in flexible AMOLED fab. Heliatek has secured €80m in additional funding for OPV manufacturing in Dresden. PragmatIC has raised ~ €20m from investors including Avery Dennison. Thinfilm invests in new production site in Silicon Valley (formerly owned by Qualcomm). Cambrios back in business after acquisition by TPK.\nApplications.\nPrinted electronics are in use or under consideration include wireless sensors in packaging, skin patches that communicate with the internet, and buildings that detect leaks to enable preventative maintenance. Most of these applications are still in the prototyping and development stages. There is a particularly growing interest for flexible smart electronic systems, including photovoltaic, sensing and processing devices, driven by the desire to extend and integrate the latest advances in (opto-)electronic technologies into a broad range of low-cost (even disposable) consumer products of our everyday life, and as tools to bring together the digital and physical worlds.\nNorwegian company ThinFilm demonstrated roll-to-roll printed organic memory in 2009.\nStandards development and activities.\nTechnical standards and road-mapping initiatives are intended to facilitate value chain development (for sharing of product specifications, characterization standards, etc.) This strategy of standards development mirrors the approach used by silicon-based electronics over the past 50 years. Initiatives include:\nIPC—Association Connecting Electronics Industries has published three standards for printed electronics. All three have been published in cooperation with the Japan Electronic Packaging and Circuits Association (JPCA):\nThese standards, and others in development, are part of IPC's Printed Electronics Initiative.", "Engineering,_Manufacturing": 0.9999604225, "qwen": "Yes"}
{"id": "6055566", "revid": "1461430", "url": "https://en.wikipedia.org/wiki?curid=6055566", "title": "S-graph", "text": "The S-graph framework is an approach to solving batch process scheduling problems in chemical plants. S-graph is suited for the problems with a non-intermediate storage (NIS) policy, which often appears in chemical productions, but it is also capable of solving problems with an unlimited intermediate storage (UIS) policy.\nOverview.\nThe S-graph representation exploits problem-specific knowledge to develop efficient scheduling algorithms. In the scheduling problem, there are products, and a set of tasks, which have to be performed to produce a product. There are dependencies between the tasks, and every task has a set of needed equipment that can perform the task. Different processing times can be set for the same task in different equipment types. It is possible to have more pieces of equipment of the same type, or define changeover times between two tasks performed on a single piece of equipment.\nThere are two types of the scheduling problems that can be handled:", "Engineering,_Manufacturing": 0.9999771118, "qwen": "Yes"}
{"id": "18355561", "revid": "1150665934", "url": "https://en.wikipedia.org/wiki?curid=18355561", "title": "Electrohydraulic forming", "text": "Electrohydraulic forming is a type of process in which an electric arc discharge in liquid is used to convert electrical energy to mechanical energy and change the shape of the workpiece. A capacitor bank delivers a pulse of high current across two electrodes, which are positioned a short distance apart while submerged in a fluid (water or oil). The electric arc discharge rapidly vaporizes the surrounding fluid, creating a shock wave. The workpiece, which is kept in contact with the fluid, is deformed into an evacuated die.\nThe potential forming capabilities of submerged arc discharge processes were recognized as early as the mid-1940s (Yutkin L.A.). During the 1950s and early 1960s, the basic process was developed into production systems. This work principally was by and for the aerospace industries. By 1970, forming machines based on submerged arc discharge were available from machine tool builders. A few of the larger aerospace fabricators built machines of their own design to meet specific part fabrication requirements.\nElectrohydraulic forming (EHF) is based on the ultra-high-speed deformation of metal using shockwaves in water. Using the discharge of current from a capacitor bank, an electric arc is generated in water between two electrodes. This electric arc vaporizes the surrounding water, converting electrical energy into an intense shockwave of mechanical energy.\nThe shockwave simultaneously transforms the metal workpiece into a visco-plastic state and accelerates it into a die, enabling forming of complex shapes at high speeds in cold conditions. All of which happens in a matter of milliseconds; total cycle time of seconds including charging time of the system. This process is not limited by size and allows forming of parts up to a few square meters in size. An array of electrodes can be placed over a large workpiece, enabling pressure distribution according to the product’s topology, still using a one-sided die to create complex shapes and fine details.\nVery large capacitor banks are needed to produce the same amount of energy as a modest mass of high explosives - which is expensive for large parts. On the other hand, the electrohydraulic method was seen as better suited to automation because of the fine control of multiple, sequential energy discharges and the relative compactness of the electrode-media containment system.\nAdvantages of EHF", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "18356461", "revid": "6307086", "url": "https://en.wikipedia.org/wiki?curid=18356461", "title": "Production support", "text": "Production support covers the practices and disciplines of supporting the IT systems/applications which are currently being used by the end users. A production support person/team is responsible for monitoring the production servers, scheduled jobs, incident management and receiving incidents and requests from end-users, analyzing these and either responding to the end user with a solution or escalating it to the other IT teams. These teams may include developers, system engineers and database administrators.\nThe importance of production support.\nIn order to understand the importance of production support, one needs to take a few factors into account.\nFrom the factors listed above, one can see that the way in which production support is managed is extremely crucial.\nProduction Support Steps.\nThe major steps for Production Support are as below. These Production Support steps are in context of the Batch processing.\nRecording Production Error.\nUsually a batch job or group of related batch jobs (schedule/stream) runs to accomplish one or more business functions. These batch jobs run unattended and normally complete without any errors or issues. However, sometimes the batch job can have a break/interruption/abend/abort. There could be several reasons why a job could abend.\nWhen a job abends, it can send out an automated alert notification via e-mail, page, text. Also, data center or operations team is also actively monitoring the jobs. They also send alert notification using e-mail, page, text or they can call the on call person responsible for the recovery of the abended job.\nThe on call person acknowledges the e-mail, page, text or phone call for the abended job. The on call person also records the abended job details in a production issue tracking system. Sometimes, the abended job automatically records the job abend details along with job standard list (job log) in a production issue tracking system. The abended job details (job standard list, error log files, etc.) are available in the production job scheduler tool. The Production issue tracking tool creates a request number and this request number is given to the support team. This request number is used to track the progress of the production support issue. The request is assigned to on call support team person.\nNotification of Production Error.\nFor critical Production Errors (e.g. Production job is in critical path and is likely to delay the batch completion SLAs and if the Production error is impacting business data), an e-mail is sent to entire organization or impacted teams so that they are aware of the issue. They are also provided with the estimated time for Production error recovery.\nInvestigation or Analysis of Production Error.\nThe Production support team on call person collects all the necessary information about the Production error. This information is then recorded in the Production error tracking tool using the correct support request number previously assigned. All the details such as data, environment, process, program logic that failed is used in the investigation. Production batch job, program used or any tool/utility used is reviewed for any possible errors.\nResolution of Production Error.\nIf similar Production error occurred in the past then the issue resolution steps are retrieved from the support knowledge base and error is resolved using those steps. If it is a new Production error then new Production error resolution steps are created and Production error is resolved. The new Production error resolution steps are recorded in the knowledge base for the future usage. For major Production errors (critical infrastructure or application failures), a phone conference call is initiated and all required support persons/teams join the call and they all work together to resolve the error. This is also called as an Incident Management. If a problem occurs repeatedly then it is recorded and tracked using appropriate tools and processes until it is resolved permanently. This is also called as Problem Management. The issue is closed only after the customer or end user agrees that the problem is resolved.\nProduction job/program code correction.\nIf the Production error occurred due to programming errors then a request is created for the Development team to correct programming errors. Problem is identified, defined and root cause analysis is performed. The programming error is fixed using normal SDLC process - analysis/design/programming/QA/testing/release. The new version of the Production job/program is deployed and verified/validated.\nProduction Process correction.\nIf the Production error occurred due to job/schedule dependency issues or sequence issues then further analysis is done to find the correct sequence/dependencies. The new sequence/dependencies are verified and validated in test environment before Production deployment.\nInfrastructure Issue correction.\nIf the Production error occurred due to infrastructure issues then the specific infrastructure team is notified. The infrastructure team then implements permanent fix for the issue and monitors the infrastructure to avoid same error again.\nProduction Support Billing.\nIf the Production error occurred due to unexpected consequences of infrastructure changes then most often the infrastructure team is not able to bill the time spent in resolving of the issue at the full rate. In some cases hours are completely disqualified from being billed.\nProduction Support - Follow up and Reporting.\nThe Production error tracking system is used to review all issues periodically (daily, weekly and monthly) and reports are generated to monitor resolved issues, repeating issues, pending issues. Reports are also generated for the IT/IS management for improvement and management of Production jobs.", "Engineering,_Manufacturing": 0.8321718574, "qwen": "Yes"}
{"id": "17062218", "revid": "38132428", "url": "https://en.wikipedia.org/wiki?curid=17062218", "title": "Product teardown", "text": "A product teardown, or simply teardown, is the act of disassembling a product, such that it helps to identify its component parts, chip & system functionality, and component costing information. For products having 'secret' technology, such as the Mikoyan-Gurevich MiG-25, the process may be secret. For others, including consumer electronics, the results are typically disseminated through photographs and component lists so that others can make use of the information without having to disassemble the product themselves. This information is important to designers of semiconductors, displays, batteries, packaging companies, integrated design firms, and semiconductor fabs, and the systems they operate within.\nThis information can be of interest to hobbyists, but can also be used commercially by the technical community to find out, for example, what semiconductor components are being utilized in consumer electronic products, such as the Wii video game console or Apple's iPhone. Such knowledge can aid understanding of how the product works, including innovative design features, and can facilitate estimating the bill of materials (BOM). The financial community, therefore, has an interest in teardowns, as knowing how a company's products are built can help guide a stock valuation. Manufacturers are often not allowed to announce what components are present in a product due to non-disclosure agreements (NDA). Teardowns can also play a part in evidence of use in court and litigation proceedings where a company's parts may have been used without their permission, counterfeited, or to show where intellectual property or patents might be infringed by another firm's part or system.\nIdentifying semiconductor components in systems has become more difficult over the past years. The most notable change started with Apple's 8GB iPod nano, which were repackaged with Apple branding. This makes it more difficult to identify the actual device manufacturer and function of the component without performing a 'delid' – removing the outer packaging to analyze the die within it. Typically there are markings on the die inside the package that can lead experienced engineers to see who actually created the device and what functionality it performs in the system.", "Engineering,_Manufacturing": 0.9943570495, "qwen": "Yes"}
{"id": "17063194", "revid": "13975403", "url": "https://en.wikipedia.org/wiki?curid=17063194", "title": "Tube beading", "text": "Tube beading is a metal forming process that forms a bead on the end of a tube. Tube beads can be used to help hold a hose on the end of a tube or to strengthen the end of the tube. There are two forming processes: \"internal roll forming\" and \"ram forming\".\nInternal roll forming.\nInternal roll forming is generally slower than ram forming but it holds tight tolerances. Serrated clamp jaws are used to hold the tube while radial pressure is applied by an internal roller to form the bead.\nRam forming.\nRam forming is quicker and usually preferred when speed of production is a concern. The automotive industry usually uses this process over internal roll-forming. A clamp is used to hold the tube, the tube is expanded to desired diameter by an expansion punch, and then another punch is used to reduce the tube back to pilot diameter. Multiple beads are possible using this process.", "Engineering,_Manufacturing": 1.0000040531, "qwen": "Yes"}
{"id": "17088005", "revid": "2304267", "url": "https://en.wikipedia.org/wiki?curid=17088005", "title": "Notching", "text": "Notching is a metal-cutting process used on sheet-metal or thin bar-stock, sometimes on angle sections or tube. A shearing or punching process is used in a press, so as to cut vertically down and perpendicular to the surface, working from the edge of a work-piece. Sometimes the goal is merely the notch itself, but usually this is a precursor to some other process: such as bending a corner in sheet or joining two tubes at a tee joint, notching one to fit closely to the other.\nNotching is a low-cost process, particularly for its low tooling costs with a small range of standard punches. The capital cost of the punch press can be expensive though, so small fabrication shops often out-source their notching work to a press shop or notching specialist. Notching of large or heavy sections, particularly for large tube fabrication or HVAC, is increasingly carried out by plasma-cutting rather than punch tools. The first punch & die type tool for notching tube & pipe was invented in Chicago by Julius Vogel, who was issued a US patent in 1938.\nThe accuracy of punch notching is good, depending on the care with which it's carried out. For manual folding work, prior notching can often improve resultant accuracy of the folding itself.\nThe speed of notching is usually limited by manual handling when loading the workpieces into the press. Pieces some feet long may be manually loaded into a single-stroke press. Smaller pieces are still generally hand-fed, limiting speeds to perhaps 100 strokes / minute.\nAlmost any workable metal can be notched. It's particularly suitable where the metal is otherwise awkward to drill, such as stainless steels, titanium or previously heat-treated aluminium alloys.\nIt is an operation of removing a small part of metal sheet of desired shape from edge of metal sheet\nTube notching.\nTube notching is commonly performed before joining light-gauge tubes to make a tee or similar joint, as by welding. Either one or both tubes may be notched before assembly. A familiar example of tube notching is in the manufacture of bicycle frames.\nEnd notching works the \"end\" of the tube, such as a semicircular concavity to make the base of a tee, or a convex vee to fit into a mitre.\nSide notching (also called offset notching) works the \"side\" of a tube with a vee notch for bending, semicircular or vee notches for tee joint.\nTube being hollow, it's not practical to use a simple punch operation to notch it, as it would be squashed. Although punching is possible, it requires support mandrels and awkward handling. Where tube is worked with a punch press other than for side notching, this is generally described as \"slotting\".\nTube notching for fabrication of circular tube is thus most commonly done with a rotary hole saw in which a hole saw of the diameter of the tube being attached to is fed into the stock to be notched at a semi-perpendicular angle. This produces a semi-circular notch. Rather than using large presses, such saw notching may only require a simple jig, also making it suitable for on-site working.\nA much more accurate way of notching the end of tube stock is to use a specially made milling cutter called an end mill. The stock to be notched is clamped into a vise and can then be fed slowly and accurately into a rotating, hardened metal, end mill. The equipment required for this method is considerably more expensive than the hole saw method and does not lend well to the same portability of the hole saw method as the machine is usually bolted to the floor for stability and safety reasons. This method of end notching is much faster and thus greatly minimizes the chance of damaging the stock either by warping due to heat build up or by squashing as can still happen with a hole saw.\nNotching in thin-wall tube may also be carried out by abrasive tools, reducing some of the risk of damage from a hole saw snatching. This also allows more complex shapes to be performed, such as vee notches. In some cases, a helical end mill cutter may be used.\nComputer numerical control (CNC) notching is enabling designers to work with more complex geometries.\nNotch and bend.\nVee notches in tube, particularly square tube, may be cut so deep as to cut almost through the tube: three sides of a square tube. This then allows torner, usually finished by welding.\nOn a smaller scale for jewellery making, this operation is performed by hand-filing precious-metal strip before bending and soldering to make box frames or stone mounts.", "Engineering,_Manufacturing": 0.9999980927, "qwen": "Yes"}
{"id": "17099492", "revid": "1234701", "url": "https://en.wikipedia.org/wiki?curid=17099492", "title": "Martempering", "text": "Martempering is also known as stepped quenching or interrupted quenching. In this process, steel is heated above the upper critical point (above the transformation range) and then quenched in a hot-oil, molten-salt, or molten-lead bath kept at a temperature of 150-300 °C. The workpiece is held at this temperature above martensite start (Ms) point until the temperature becomes uniform throughout the cross-section of the workpiece. After that, it is cooled in air or oil to room temperature. The steel is then tempered. In this process, austenite is transformed to martensite by step quenching, at a rate fast enough to avoid the formation of ferrite, pearlite, or bainite.\nIn the martempering process, austenitized metal part is immersed in a bath at a temperature just above the martensite start temperature (Ms). By using interrupted quenching, the cooling is stopped at a point above the martensite transformation region to ensure sufficient time for the center to cool to the same temperature as the surface. The metal part is then removed from the bath and cooled in air to room temperature to permit the austenite to transform to martensite. Martempering is a method by which the stresses and strains generated during the quenching of a steel component can be controlled. In martempering, steel is heated to above the critical range to make it all austenite.\nThe drawback of this process is that the large section cannot be heat treated by this process.", "Engineering,_Manufacturing": 0.9988654852, "qwen": "Yes"}
{"id": "17102553", "revid": "1165302366", "url": "https://en.wikipedia.org/wiki?curid=17102553", "title": "Curling (metalworking)", "text": "Curling is a sheet metal forming process used to form the edges into a hollow ring. Curling can be performed to eliminate sharp edges and increase the moment of inertia near the curled end. Other parts are curled to perform their primary function, such as door hinges.\nOperation.\nIn the curling operation, the flare, or burr, should always be turned away from the die. This will help prolong the life of the die by avoiding unnecessary damage due to scratching. The stroke of the die must be as long as the curl. Curling is often performed as part of a high production, multiple operation progressive forming.\nTooling.\nThe curling die is designed to curl a material of specific thickness. Dies are generally made of hardened tool steel because of the amount of wear caused by the operation. Their smooth, rounded cavities are often lapped and polished to help curl the material uniformly.", "Engineering,_Manufacturing": 0.9996874332, "qwen": "Yes"}
{"id": "17106815", "revid": "965739", "url": "https://en.wikipedia.org/wiki?curid=17106815", "title": "Filing (metalworking)", "text": "Filing is a material removal process in manufacturing. Similar, depending on use, to both sawing and grinding in effect, it is functionally versatile, but used mostly for finishing operations, namely in deburring operations. Filing operations can be used on a wide range of materials as a finishing operation. Filing helps achieve workpiece function by removing some excess material and deburring the surface. Sandpaper may be used as a filing tool for other materials, such as wood.\nBand filing.\nBand Filing takes place on a machine similar to a belt sander or band saw. Band files are sectioned similarly to a saw chain so that they can be made from stiff material, as they need to be to effectively remove material yet still work in a constant feed. A band filing operation can be used to remove small amounts of material with good accuracy. The cutting teeth of the file are arranged closely on the file and are used as part of a finishing process.\nReciprocating filing.\nReciprocating filing takes place on a flat surface where workpieces are fed into the file. The file teeth are angled so that material is removed on each downstroke of the tool. Chips removed from the workpiece fall through a cavity in front of the file. ", "Engineering,_Manufacturing": 0.9976816773, "qwen": "Yes"}
{"id": "9493693", "revid": "43845453", "url": "https://en.wikipedia.org/wiki?curid=9493693", "title": "ZQ8", "text": "ZQ8 is an RPO code designation for the Chevrolet S-10, GMC Sonoma, and Chevrolet Colorado.\nChevrolet S-10 and GMC Sonoma.\nThe ZQ8 option suspension package comes standard on the 1999-2003 S-10 Xtreme and 1996-1998 S-10 SS models, but was also available as a sports package on either the S-10 or GMC Sonoma. The package included a total lowered ride height of approximately 2\" over stock (1.5\" from suspension, ~0.5\" from shorter tire diameter), thicker front sway bar (33mm), rear sway bar (23mm), quicker ratio (12:1) steering box, upgraded Decarbon or Bilstein gas shock absorbers, and a frame brace. Some ZQ8 models were also equipped with a frame to axle \"anti-hop\" shock.\nThe lowered stance was achieved using front coils with a different spring rate, and a 3-leaf rear spring pack.\nWheels and tires were also upgraded to cast aluminum rim with 235/55/16 Goodyear Eagle GA tires. The Xtreme package used a different style rim than a standard truck equipped with the ZQ8 option. There are 2 versions of \"ZQ8\" wheels - 1996-2000 (also standard on 1996-1998 SS trucks), similar in design to 3rd generation Camaro wheels, and 2001-2003 (also used on Blazer Xtremes from 2004-2005), which bear a resemblance to an IROC Z28 wheel. Another variation among different models was in the center caps. S-10s and Sonomas used a grey center cap with the exception of the 2002-2003 S-10s, which featured a chrome center cap.\nThe suspension package can be retrofit to any 1982-2003 2wd S-Series truck, although some parts require modification, such as drilling for sway bar mounts or boring the hub on the wheels for a 1982-1993 truck. Also of note, since the package came on I4 and V6 trucks, spring rates in the coils do vary.", "Engineering,_Manufacturing": 1.0000071526, "qwen": "Yes"}
{"id": "1203787", "revid": "31907759", "url": "https://en.wikipedia.org/wiki?curid=1203787", "title": "Plasma cutting", "text": "Plasma cutting is a process that cuts through electrically conductive materials by means of an accelerated jet of hot plasma. Typical materials cut with a plasma torch include steel, stainless steel, aluminum, brass and copper, although other conductive metals may be cut as well. Plasma cutting is often used in fabrication shops, automotive repair and restoration, industrial construction, and salvage and scrapping operations. Due to the high speed and precision cuts combined with low cost, plasma cutting sees widespread use from large-scale industrial computer numerical control (CNC) applications down to small hobbyist shops.\nThe basic plasma cutting process involves creating an electrical channel of superheated, electrically ionized gas i.e. plasma from the plasma cutter itself, through the workpiece to be cut, thus forming a completed electric circuit back to the plasma cutter through a grounding clamp. This is accomplished by a compressed gas (oxygen, air, inert and others depending on material being cut) which is blown through a focused nozzle at high speed toward the workpiece. An electrical arc is then formed within the gas, between an electrode near or integrated into the gas nozzle and the workpiece itself. The electrical arc ionizes some of the gas, thereby creating an electrically conductive channel of plasma. As electricity from the cutter torch travels down this plasma it delivers sufficient heat to melt through the workpiece. At the same time, much of the high-velocity plasma and compressed gas blow the hot molten metal away, thereby separating, i.e. cutting through, the workpiece.\nPlasma cutting is an effective way of cutting thin and thick materials alike. Hand-held torches can usually cut up to thick steel plate, and stronger computer-controlled torches can cut steel up to thick. Since plasma cutters produce a very hot and very localized \"cone\" to cut with, they are extremely useful for cutting sheet metal in curved or angled shapes.\nThe arcs are generated in a three step process. A high voltage spark briefly ionizes the air within the torch head. This makes the air conductive and allows the \"pilot arc\" to form. The pilot arc forms within the torch head, with current flowing from the electrode to the nozzle inside the torch head. The pilot arc begins to burn up the nozzle, a consumable part, while in this phase. The air then blows the plasma out the nozzle towards the work, providing a current path from the electrode to the work. When the control system senses current flowing from the electrode to the work, it cuts the electrical connection to the nozzle. Current then flows from the electrode to the work, and the arc forms outside the nozzle. Cutting can then proceed, without burning up the nozzle. Nozzle life is limited by the number of arc starts, not cutting time.\nHistory.\nPlasma cutting grew out of plasma welding in the 1960s, and emerged as a very productive way to cut sheet metal and plate in the 1980s. It had the advantages over traditional \"metal against metal\" cutting of producing no metal chips, giving accurate cuts, and producing a cleaner edge than oxy-fuel cutting. Early plasma cutters were large, somewhat slow and expensive and, therefore, tended to be dedicated to repeating cutting patterns in a \"mass production\" mode.\nAs with other machine tools, CNC (computer numerical control) technology was applied to plasma cutting machines in the late 1980s into the 1990s, giving plasma cutting machines greater flexibility to cut diverse shapes \"on demand\" based on a set of instructions that were programmed into the machine's numerical control. These CNC plasma cutting machines were, however, generally limited to cutting patterns and parts in flat sheets of steel, using only two axes of motion (referred to as X Y cutting).\nSafety.\nProper eye protection and face shields are needed to prevent eye damage called arc eye as well as damage from debris. It is recommended to use green lens shade #5. OSHA recommends a shade 8 for arc current less than 300 A, but notes that \"These values apply where the actual arc is clearly seen. Experience has shown that lighter filters may be used when the arc is hidden by the workpiece.\" Lincoln Electric, a manufacturer of plasma cutting equipment, says, \"Typically a darkness shade of #7 to #9 is acceptable.\" Longevity Global, Inc., another manufacturer, offers this more specific table for eye protection for plasma arc cutting at lower amperages:\nLeather gloves, an apron and a jacket are also recommended to prevent burns from sparks and hot metal.\nWorking in a clean area free of flammable liquids, materials and gases is very important. Sparks and hot metal from a plasma cutter can quickly cause fires if they are not isolated from flammable objects. Plasma cutters can send hot sparks flying up to 1.5 meters (5 feet) away in certain situations. Machine operators are typically blind to any fire that has started because they are behind their face shields. \nStarting methods.\nPlasma cutters use a number of methods to start the arc. In some units, the arc is created by putting the torch in contact with the work piece. Some cutters use a high voltage, high frequency circuit to start the arc. This method has a number of disadvantages, including risk of electrocution, difficulty of repair, spark gap maintenance, and the large amount of radio frequency emissions. Plasma cutters working near sensitive electronics, such as CNC hardware or computers, start the pilot arc by other means. The nozzle and electrode are in contact. The nozzle is the cathode, and the electrode is the anode. When the plasma gas begins to flow, the nozzle is blown forward. A third, less common method is capacitive discharge into the primary circuit via a silicon controlled rectifier.\nInverter plasma cutters.\nAnalog plasma cutters, typically requiring more than 2 kilowatts, use a heavy mains-frequency transformer. Inverter plasma cutters rectify the mains supply to DC, which is fed into a high-frequency transistor inverter between 10 kHz to about 200 kHz. Higher switching frequencies allow smaller transformers resulting in overall size and weight reduction.\nThe transistors used were initially MOSFETs, but are now increasingly using IGBTs. With paralleled MOSFETs, if one of the transistors activates prematurely it can lead to a cascading failure of one quarter of the inverter. A later invention, IGBTs, are not as subject to this failure mode. IGBTs can be generally found in high-current machines where it is not possible to parallel enough MOSFET transistors.\nThe switch mode topology is referred to as a dual transistor off-line forward converter. Although lighter and more powerful, some inverter plasma cutters, especially those without power factor correction, cannot be run from a generator (that means manufacturer of the inverter unit forbids doing so; it is only valid for small, light portable generators). However newer models have internal circuitry that allows units without power factor correction to run on light power generators.\nCNC cutting methods.\nSome plasma cutter manufacturers build CNC cutting tables, and some have the cutter built into the table. CNC tables allow a computer to control the torch head producing clean sharp cuts. Modern CNC plasma equipment is capable of multi-axis cutting of thick material, allowing opportunities for complex welding seams that are not possible otherwise. For thinner material, plasma cutting is being progressively replaced by laser cutting, due mainly to the laser cutter's superior hole-cutting abilities.\nA specialized use of CNC plasma cutters has been in the heating, ventilating and air conditioning (HVAC) industry. Software processes information on ductwork and creates flat patterns to be cut on the cutting table by the plasma torch. This technology has enormously increased productivity within the industry since its introduction in the early 1980s.\nCNC plasma cutters are also used in many workshops to create decorative metalwork. For instance, commercial and residential signage, wall art, address signs, and outdoor garden art.\nIn recent years there has been even more development. Traditionally the machines' cutting tables were horizontal, but now vertical CNC plasma cutting machines are available, providing for a smaller footprint, increased flexibility, optimum safety and faster operation.\nCNC plasma cutting configurations.\nThere are three main configurations of CNC plasma cutting, and they are largely differentiated by the forms of materials before processing, and the flexibility of the cutting head.\n2-dimensional / 2-axis plasma cutting.\nThis is the most common and conventional form of CNC plasma cutting. Producing flat profiles, where the cut edges are at 90 degrees to the material surface. High powered cnc plasma cutting beds are configured in this way, able to cut profiles from metal plate up to 150 mm thick.\n3-dimensional / 3+ axis plasma cutting.\nOnce again, a process for producing flat profiles from sheet or plate metal, however with the introduction of an additional axis of rotation, the cutting head of a CNC plasma cutting machine can tilt whilst being taken through a conventional 2-dimensional cutting path. The result of this is cut edges at an angle other than 90 degrees to the material surface, for example 30-45 degree angles. This angle is continuous throughout the thickness of the material. This is typically applied in situations where the profile being cut is to be used as part of a welded fabrication as the angled edge forms part of the weld preparation. When the weld preparation is applied during the CNC plasma cutting process, secondary operations such as grinding or machining can be avoided, reducing cost. The angular cutting capability of 3-dimensional plasma cutting can also be used to create countersunk holes and chamfer edges of profiled holes.\nTube and section plasma cutting.\nUsed in the processing of tube, pipe or any form of long section. The plasma cutting head usually remains stationary whilst the workpiece is fed through, and rotated around its longitudinal axis. There are some configurations where, as with 3-dimensional plasma cutting, the cutting head can tilt and rotate. This allows angled cuts to be made through the thickness of the tube or section, commonly taken advantage of in the fabrication of process pipework where cut pipe can be provided with a weld preparation in place of a straight edge.\nNew technology.\nIn the past decade plasma torch manufacturers have engineered new models with a smaller nozzle and a thinner plasma arc. This allows near-laser precision on plasma cut edges. Several manufacturers have combined precision CNC control with these torches to allow fabricators to produce parts that require little or no finishing.\nCosts.\nPlasma torches were once quite expensive. For this reason they were usually only found in professional welding shops and very well-stocked private garages and shops. However, modern plasma torches are becoming cheaper, and now are within the price range of many hobbyists, less than $300. Older units may be very heavy, but still portable, while some newer ones with inverter technology weigh only a little, yet equal or exceed the capacities of older ones.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "18373732", "revid": "42727488", "url": "https://en.wikipedia.org/wiki?curid=18373732", "title": "Castability", "text": "Castability is the ease of forming a quality casting. A very castable part design is easily developed, incurs minimal tooling costs, requires minimal energy, and has few rejections. Castability can refer to a part design or a material property.\nPart design.\nPart design and geometry directly affect the castability, with volume, surface area and the number of features being the most important attributes. \nIf the design has undercuts or interior cavities it decreases castability due to tooling complexity. Long thin sections in a design are hard to fill. Sudden changes in wall thickness reduce castability because it induces turbulence during filling; fillets should be added to avoid this. Annulars in the path of flow should be avoided because they can cause cold shuts or misruns. A design that causes isolated hot spots decreases castability. An ideal design would have progressive directional solidification from the thinnest section to the thickest.\nLocation of the mold's parting line also affects castability, because a non-planar parting line also increases tooling complexity.\nIf a design requires a high degree of accuracy, fine surface finish or defect free surface it reduces the castability of the part. However, the casting process can be very economical for part designs that require intricate contoured surfaces, thickness variations, and internal features.\nQuantitative analysis.\nThe castability of a design can be partially quantitatively determined by the following three equations. Better castability is denoted by a larger number.\nWhere Vc is the volume of the casting and Vb is the volume of the smallest box that the casting could fit in.\nWhere Vc is the volume of the casting and Ac is the surface area of the casting\nWhere nf is the number of features (holes, pockets, slots, bosses, ribs, etc.)\nMaterial properties.\nMaterial properties that influence their castability include their pouring temperature, fluidity, solidification shrinkage, and slag/dross formation tendencies.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "18398883", "revid": "41927601", "url": "https://en.wikipedia.org/wiki?curid=18398883", "title": "Key (engineering)", "text": "In mechanical engineering, a key is a machine element used to connect a rotating machine element to a shaft. The key prevents relative rotation between the two parts and may enable torque transmission. For a key to function, the shaft and rotating machine element must have a keyway and a keyseat, which is a slot and pocket in which the key fits. The whole system is called a keyed joint. A keyed joint may allow relative axial movement between the parts.\nCommonly keyed components include gears, pulleys, couplings, and washers.\nTypes.\nThere are five main types of keys: \"sunk\", \"saddle\", \"tangent\", \"round\", and \"spline\".\nSunk key.\nTypes of sunk keys: \"rectangular\", \"square\", \"parallel sunk\", \"gib-head\", \"feather\", and \"Woodruff\".\nParallel keys.\n\"Parallel keys\" are the most widely used. They have a square or rectangular cross-section. Square keys are used for smaller shafts and rectangular faced keys are used for shaft diameters over or when the wall thickness of the mating hub is an issue. Set screws often accompany parallel keys to lock the mating parts into place. The keyway is a longitudinal slot in both the shaft and mating part.\nwhere\nWoodruff keys.\nWoodruff keys are semicircular, fitting partly into a circular segment keyway with the remainder fitting into a longitudinal slot keyway in the mating part. The circular segment can be cut directly by plunge cutting with a circular Woodruff cutter without any reliefs. The main advantage of the Woodruff key is the elimination of milling near shaft shoulders, where stress concentrations, and concentricity would be affected. The latter is particularly important for high speed operation. The more exact fit of the key and keyway also reduces play, and stress concentrations in, and improves the reliability of the key. An additional advantage is a stuck key can be removed from a shaft with a hammer blow, the circular profile will push the key out of the slot, as opposed to a standard key which will need to be pushed axially, or pulled out of its slot. Common applications include machine tools, automotive applications, snowblowers and marine propellers.\nThis type of key was developed by William N. Woodruff of Hartford Connecticut. In 1888, he was awarded the John Scott Medal by the Franklin Institute for his invention.\nTapered keys.\nThe tapered key is tapered only on the side that engages the hub. The keyway in the hub has a taper that matches that of the tapered key. Some taper keys have a \"gib\", or tab, for easy removal during disassembly. The purpose of the taper is to secure the key itself, as well as to firmly engage the shaft to the hub without the need for a set screw. The problem with taper keys is that they can cause the center of the shaft rotation to be slightly off of the mating part. It is different from a tapered shaft lock in that tapered keys have a matching taper on the keyway, while tapered shaft locks do not.\nOthers.\nA \"Scotch key\" or \"Dutch key\" features a circular keyway hole (instead of rectangular), produced by drilling axially into the assembled hub and shaft, with a metal dowel pin serving as the key. If the hole and key are tapered, the key is referred to as a \"Dutch pin\", which is driven in and optionally finished by cutting or grinding flush with the end of the shaft. If a straight Dutch keyway hole is optionally tapped with a thread, then an ordinary screw serves as the threaded Dutch key.\nSpring pins are an alternative Dutch key component, instead of solid dowel pins. A spring pin is self-fastening and does not work loose under vibration. Hollow spring pins provide a weaker shear strength than a solid dowel pin, and the strength may be varied by varying the wall thickness. This limited shear strength specification is designed to sustain normal operation, but then give way in the event of excessive shaft torque, thus protecting the rest of the machine from damage.\nIntroducing an additional bushing component between hub and shaft improves the performance and convenience of keyed joints. \"Taper-Lock\" bushings are keyed hub fittings which provide three threaded Dutch keyways and two setscrews as Dutch keys, in addition to the rectangular keyway. The Dutch keyways are threaded only on the alternate hub side or shaft side, with a thread clearance hole form on the opposite side. By simply driving setscrews into selected holes, the hub mechanism conveniently operates to rigidly lock or definitely release from the shaft, without hammering or hub-pulling. Quick-disconnect (\"QD\") bushings work similarly, but place a circular pattern of three unthreaded and three fully threaded holes further out from the shaft axis on a bushing flange, instead of across the bushing-to-hub interface.\nA Hirth joint is similar to a spline joint but with the teeth on the end of the shaft instead of on the surface.\nSaddle keys.\nThese types of keys are generally attached to the driving member (e.g. shafts). These types of keys have less strength as compared with the sunk keys. These are rarely used keys, to transmit lower power to the driven members (e.g. couplings)\nTangent keys.\nTangent keys are used in high-torque heavy-duty applications. What would have been the side of each keyway forms heels against which the key sits, and transfers force compressively. This latter point means that for reversible motion of the shaft, another key along a tangent outwards in the opposing direction is needed. Typically this will be offset by 90° or 180° on the shaft. The key may be wedge, rectangular, or square shaped, but particularly rectangular double-taper keys are used.\nSpline key.\nThis type of key uses multiple keyways in the hub to transmit high power.\nKeyseating.\n\"Keyseating\" is the creation of the slots in the mating items. Keyseating can be done on a variety of different machines including a broach, a keyseater, wire-cut EDM, a shaper or vertical slotting machine, either a vertical or horizontal mill, or with a chisel and file.\nBroaching.\nBroaching is primarily used to cut square cornered internal keyways. The specific broach, bushing and guide are used for each given keyway cross-section, which makes this process more expensive than most of the alternatives. However, it can produce the most accurate keyway out of all the processes. There are three main steps in broaching a keyway: First, the workpiece is set on the arbor press and the bushing is placed in the opening of the workpiece. Next, the broach is inserted and pushed through, cutting the keyway. Finally, shims are placed between the bushing and the broach to achieve the correct depth necessary for the key.\nKeyseater.\n\"Keyseaters\", also known as \"keyseating machines\" and \"keyway cutters\", are specialized machines designed to cut keyways. They are very similar to vertical shapers; the difference is that the cutting tool on a keyseater enters the workpiece from the bottom and cuts on the down-stroke, while the tool on a shaper enters the workpiece from the top and cuts downward. Another difference is a keyseater has a guiding system above the workpiece to minimize deflection, which results in a closer tolerance cut. The process starts by clamping the workpiece to the table with a fixture or vise. The workpiece is properly located and then the reciprocating arm is started. Some models have a stationary table so the cutter is fed horizontally into the workpiece, while others have a movable table that feeds the workpiece into a fixed cutter. These machines can cut other straight sided features other than keyways (see the picture). They can also produce blind slots, which are slots that do not extend through the whole workpiece.\nWire-cut electrical-discharge machining (EDM).\nWire-cut electrical-discharge machining (EDM) is primarily used for small production lot sizes where either extreme precision is required or other cutting technologies are not readily available. Wire-cut EDM cuts keyways by eroding material away from the workpiece through a series of rapid electric current discharges between a spooling wire and the workpiece through a dielectric liquid. Computer numerical control (CNC) wire-cut EDM machines allow for a wide variety selection of keyways to be cut, inclusive of multiple keyways on the same hub. The main limitations of CNC wire-cut EDM is the time it takes to cut a keyway as well as the size of parts a given wire-cut EDM machine can accommodate.\nShaping or slotting.\nShaping or slotting is largely used for cutting keyways that do not extend through the full length of the part. Like keyseating, shaping uses a single-point cutting tool for cutting, however, shapers are not guided through the cut on a fixed post. As such, shaper cuts are generally more susceptible to deflection than keyseater cuts.\nMilling.\nParallel, tapered, and Woodruff keyways can be produced on a milling machine. End mills or slotting cutters are used for parallel and tapered keyways, while a Woodruff cutter is used for Woodruff keyways.\nFor internal keyways that are not too long, the keyways can be milled if a radius is acceptable.\nChiseling.\nOne of the earliest forms of keyseating was done by chiseling. The keyway is roughed out using a chisel and then filed to size; the key is tried frequently to avoid over filing. This technique is long, tedious, and rarely used anymore.\nKeyed joints.\nA \"shear key\" is a feature intended to fail and avoid further damage should the machinery be accidentally operated in excess of its design limits. Shear keys may be any of the designs described above, but are made from a weaker material than the shaft. The shear key is easily and inexpensively replaced, and avoids more serious damage to the mechanism that would be costly or difficult to repair. For example, a steel shaft and pulley may employ a brass key. When excessive torque is applied to the joint, the steel edges shear the brass key into two pieces, leaving the pulley spinning loosely on the shaft and relieving the rest of the machine from possible damage.\nTwo parallel keys can be used if the shaft connection requires a higher torque rating.\nImproperly machined keyways that had cutter deflection or drifting occur, may not be strong enough for the required application.", "Engineering,_Manufacturing": 0.9999958277, "qwen": "Yes"}
{"id": "1568958", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=1568958", "title": "Inconel", "text": "Inconel is a nickel-chromium-based superalloy often utilized in extreme environments where components are subjected to high temperature, pressure or mechanical loads. Inconel alloys are oxidation- and corrosion-resistant, when heated, Inconel forms a thick, stable, passivating oxide layer protecting the surface from further attack. Inconel retains strength over a wide temperature range, attractive for high-temperature applications where aluminum and steel would succumb to creep as a result of thermally-induced crystal vacancies. Inconel's high-temperature strength is developed by solid solution strengthening or precipitation hardening, depending on the alloy.\nInconel alloys are typically used in high temperature applications. Common trade names for\nHistory.\nThe Inconel family of alloys was first developed before December 1932, when its trademark was registered by the International Nickel Company of Delaware and New York. A significant early use was found in support of the development of the Whittle jet engine, during the 1940s by research teams at Henry Wiggin & Co of Hereford, England a subsidiary of the Mond Nickel Company, which merged with Inco in 1928. The Hereford Works and its properties including the Inconel trademark were acquired in 1998 by Special Metals Corporation.\nComposition.\nInconel alloys vary widely in their compositions, but all are predominantly nickel, with chromium as the second element.\nProperties.\nWhen heated, Inconel forms a thick and stable passivating oxide layer protecting the surface from further attack. Inconel retains strength over a wide temperature range, attractive for high-temperature applications where aluminium and steel would succumb to creep as a result of thermally induced crystal vacancies (see Arrhenius equation). Inconel's high temperature strength is developed by solid solution strengthening or precipitation strengthening, depending on the alloy. In age-hardening or precipitation-strengthening varieties, small amounts of niobium combine with nickel to form the intermetallic compound Ni3Nb or gamma double prime (γ″). Gamma prime forms small cubic crystals that inhibit slip and creep effectively at elevated temperatures. The formation of gamma-prime crystals increases over time, especially after three hours of a heat exposure of , and continues to grow after 72 hours of exposure.\nStrengthening Mechanisms.\nThe most prevalent hardening mechanisms for Inconel alloys are precipitate strengthening and solid solution strengthening. In Inconel alloys, one of the two often dominates. For alloys like Inconel 718, precipitate strengthening is the main strengthening mechanism. The majority of strengthening comes from the presence of gamma double prime (γ″) precipitates. Inconel alloys have a γ matrix phase with an FCC structure. γ″ precipitates are made of Ni and Nb, specifically with a Ni3Nb composition. These precipitates are fine, coherent, disk-shaped, intermetallic particles with a tetragonal structure.\nSecondary precipitate strengthening comes from gamma prime (γ') precipitates. The γ' phase can appear in multiple compositions such as Ni3(Al, Ti). The precipitate phase is coherent and has an FCC structure, like the γ matrix; The γ' phase is much less prevalent than γ″. The volume fraction of the γ″ and γ' phases are approximately 15% and 4% after precipitation, respectively. Because of the coherency between the γ matrix and the γ' and γ″ precipitates, strain fields exist that obstruct the motion of dislocations. The prevalence of carbides with MX(Nb, Ti)(C, N) compositions also helps to strengthen the material. For precipitate strengthening, elements like niobium, titanium, and tantalum play a crucial role. \nBecause the γ″ phase is metastable, over-aging can result in the transformation of γ″ phase precipitates to delta (δ) phase precipitates, their stable counterparts. The δ phase has an orthorhombic structure, a Ni3(Nb, Mo, Ti) composition, and is incoherent. As a result, the transformation of γ″ to δ in Inconel alloys leads to the loss of coherency strengthening, making for a weaker material. That being said, in appropriate quantities, the δ phase is responsible for grain boundary pinning and strengthening.\nAnother common phase in Inconel alloys is the Laves intermetallic phase. Its compositions are (Ni, Cr, Fe)x(Nb, Mo, Ti)y and NiyNb, it is brittle, and its presence can be detrimental to the mechanical behavior of Inconel alloys. Sites with large amounts of Laves phase are prone to crack propagation because of their higher potential for stress concentration. Additionally, due to its high Nb, Mo, and Ti content, the Laves phase can exhaust the matrix of these elements, ultimately making precipitate and solid-solution strengthening more difficult. \nFor alloys like Inconel 625, solid-solution hardening is the main strengthening mechanism. Elements like Mo are important in this process. Nb and Ta can also contribute to solid solution strengthening to a lesser extent. In solid solution strengthening, Mo atoms are substituted into the γ matrix of Inconel alloys. Because Mo atoms have a significantly larger radius than those of Ni (209 pm and 163 pm, respectively), the substitution creates strain fields in the crystal lattice, which hinder the motion of dislocations, ultimately strengthening the material. \nThe combination of elemental composition and strengthening mechanisms is why Inconel alloys can maintain their favorable mechanical and physical properties, such as high strength and fatigue resistance, at elevated temperatures, specifically those up to 650°C. \nMachining.\nInconel is a difficult metal to shape and to machine using traditional cold forming techniques due to rapid work hardening. After the first machining pass, work hardening tends to plastically deform either the workpiece or the tool on subsequent passes. For this reason, age-hardened Inconels such as 718 are typically machined using an aggressive but slow cut with a hard tool, minimizing the number of passes required. Alternatively, the majority of the machining can be performed with the workpiece in a \"solutionized\" form, with only the final steps being performed after age hardening. However some claim that Inconel can be machined extremely quickly with very fast spindle speeds using a multifluted ceramic tool with small depth of cut at high feed rates as this causes localised heating and softening in front of the flute.\nExternal threads are machined using a lathe to \"single-point\" the threads or by rolling the threads in the solution treated condition (for hardenable alloys) using a screw machine. Inconel 718 can also be roll-threaded after full aging by using induction heat to without increasing the grain size. Holes with internal threads are made by threadmilling. Internal threads can also be formed using a sinker electrical discharge machining (EDM).\nJoining.\nWelding of some Inconel alloys (especially the gamma prime precipitation hardened family; e.g., Waspaloy and X-750) can be difficult due to cracking and microstructural segregation of alloying elements in the heat-affected zone. However, several alloys such as 625 and 718 have been designed to overcome these problems. The most common welding methods are gas tungsten arc welding and electron-beam welding.\nUses.\nInconel is often encountered in extreme environments. It is common in gas turbine blades, seals, and combustors, as well as turbocharger rotors and seals, electric submersible well pump motor shafts, high temperature fasteners, chemical processing and pressure vessels, heat exchanger tubing, steam generators and core components in nuclear pressurized water reactors, natural gas processing with contaminants such as H2S and CO2, firearm sound suppressor blast baffles, and Formula One, NASCAR, NHRA, and APR, LLC exhaust systems. It is also used in the turbo system of the 3rd generation Mazda RX7, and the exhaust systems of high powered Wankel engined Norton motorcycles where exhaust temperatures reach more than . Inconel is increasingly used in the boilers of waste incinerators. The Joint European Torus and DIII-D tokamaks' vacuum vessels are made of Inconel. Inconel 718 is commonly used for cryogenic storage tanks, downhole shafts, wellhead parts, and in the aerospace industry -- where it has become a prime candidate material for constructing heat resistant turbines.\nAutomotive.\nRolled Inconel was frequently used as the recording medium by engraving in black box recorders on aircraft.\nAlternatives to the use of Inconel in chemical applications such as scrubbers, columns, reactors, and pipes are Hastelloy, perfluoroalkoxy (PFA) lined carbon steel or fiber reinforced plastic.\nInconel alloys.\nAlloys of inconel include:\nIn age hardening or precipitation strengthening varieties, alloying additions of aluminum and titanium combine with nickel to form the intermetallic compound or gamma prime (γ′). Gamma prime forms small cubic crystals that inhibit slip and creep effectively at elevated temperatures.", "Engineering,_Manufacturing": 0.9999930859, "qwen": "Yes"}
{"id": "47374440", "revid": "32799598", "url": "https://en.wikipedia.org/wiki?curid=47374440", "title": "Butterfly (company)", "text": "Butterfly also known as Butterfly Pictures was a film production company that produced and released films spanned as part of the Universal Film Manufacturing Company program from 1917 to 1918.\nHistory.\nOn April 28, 1917, Butterfly Pictures was announced in \"Motography\" a new brand of feature films that would be released as part of the Universal exchanges. These films would be five reels in length and would be produced at the Universal Film Manufacturing Company studios in California.", "Engineering,_Manufacturing": 0.9989258051, "qwen": "Yes"}
{"id": "47391546", "revid": "10962546", "url": "https://en.wikipedia.org/wiki?curid=47391546", "title": "Asteelflash Group", "text": "Asteelflash Group is a French multinational electronics contract manufacturing company specializing in printed circuit board assembly and also offering design and aftermarket services.\nHeadquartered in Neuilly-Plaisance, France, it is the second largest electronics manufacturing services(EMS) company in Europe and ranks among top 20 worldwide with manufacturing operations in 18 countries, totaling approximately 2 million square feet and 5,700 employees.\nHistory.\nIn 1999, the company was founded in Paris, France as Asteel by Gilles Benhamou. The EMS company experienced rapid growth through acquisitions. Asteel then extended its operations into North Africa and Europe and acquired new premises in both Tunisia (in Mégrine and Fouchana) and the United Kingdom (in Bedford, England).\nIn 2008, Asteel acquired Flash Electronics, an American EMS company founded in 1994, and developed it into a multinational company, operating since then under the name Asteelflash. In so doing, the company reinforced its global footprint with new facilities in the USA (in Fremont, California) and in China (in Suzhou, Jiangsu).\nIn 2012, Asteelflash acquired American Catalyst Manufacturing Services, Inc. with plants in Raleigh, North Carolina and in Tijuana, Baja California, Mexico. Hoping to establish a permanent foothold in the European market, Asteelflash acquired French TES Electronic Solutions in 2011 and German EN ElectronicNetwork in 2012.\nIn 2020, Asteelflash was acquired by USI, Universal Scientific Industrial (Shanghai) Co., Ltd. USI is a contract manufacturer (EMS and ODM) with a dual-headquarter in Shanghai and Taiwan.\nRanking No. 2 in Europe and among top 20 worldwide, Asteelflash's competitors are industry heavyweights such as: Flextronics (Singapore), Jabil (United States) or Foxconn (Taiwan), Benchmark (United States), Celestica (Canada), Plexus (United States) and Zollner (Germany).\nMarket segments.\nAsteelflash has manufacturing operations in eight countries on four continents, totaling 18 plants, approximately 2 million square feet manufacturing surface and +6,000 employees.\nAsteelflash Group demarcated its global footprint into four geographical divisions, listed below.\nAMERICAS.\n300,000 ft2, 400 employees\nWest EMEA.\n610,000 ft², 2,044 employees\nEast EMEA.\n329,000 ft2, 700 employees", "Engineering,_Manufacturing": 0.9999679327, "qwen": "Yes"}
{"id": "10160476", "revid": "40561892", "url": "https://en.wikipedia.org/wiki?curid=10160476", "title": "Motorcycle design", "text": "Motorcycle design can be described as activities that define the appearance, function and engineering of motorcycles.\nProfessionally it is a branch of industrial design, similar to automotive design using identical techniques and methodology, but confined by a set of conventions about what is acceptable to the buying public. These conventions have been defined by the acceptance of the industry and media as a whole to the assumption that the public will only purchase machines that bear more than a passing resemblance to competition machines of whatever kind. In some large OEM motorcycle manufacturers, the term designer can also be applied to the project leader or chief engineer charged with laying down the principal architecture of the vehicle. In recent years, it has also become associated with custom or \"chopper\" builder culture.\nProfessional design.\nProfessional motorcycle designers almost always hold degrees in industrial design, industrial design engineering or similar, and have training in styling, modeling, as well as knowledge in aspects of technology associated with single track vehicles. Although no degree as a specialisation exists per se, the majority of candidates graduate through colleges and universities with established transportation design courses, and are trained as automotive designers.\nMost OEM motorcycle manufacturers, such as Honda, Suzuki, Kawasaki, BMW, Ducati, Piaggio and others have in-house design studios dedicated to this purpose, while others such as Yamaha and KTM depend on specialised independent design consultancies.\nMethodology.\nDesign and engineering relationships.\nDue to the high importance of mechanical components or even exposed engines to motorcycle styling, almost always designers will have a greater sensitivity to and awareness of engineering than will typical car designers. In OEM situations, large teams of professional engineers and specialists will collaborate on each project development, allowing the designer to focus on the more intangible or subjective aspects of design, such as styling, human-machine interface psychology, and market and cultural relationships. In other matters such as pure mechanical ergonomics (such as seat height, handlebar placement, etc.), or basic layout (the location of major components, storage, etc.) there is usually considerable overlap between the designer and engineer. The designer will nominally approach each problem from a human interface, or \"feel\" or \"irrational\" point of view (example : \"Does this material feel cold or warm, and is this feeling appropriate to this vehicle's target consumer?\"), while the engineer will attack each problem with the \"rational\" or clinical approach of empirically weighing the cause and effect of each design decision against the project's technical and economic design targets (example : \"Can this material be moulded into the designer's desired shape? Will that be too expensive to produce?\")\nResearch and Concept Design.\nIn OEM motorcycle design, the normal procedure of developing a new motorcycle involves the same steps as in other professional design disciplines : identifying a target consumer, researching them to identify benchmarks and project targets, then proposing concept directions in a written form known as a Design Brief or QFD. From this point, artwork is developed to visually communicate the designer's ideas. These are presented in 2Db drawing or illustrated form, from which a winning direction is down selected for further development. Once a satisfactory design is established on paper (the term paper is a generalization that can include traditional hand renderings, digital artwork or CAD drawings), then full scale modeling begins to realise the design in tangible 3D form.\nStyling.\nOften used as an interchangeable term with \"design\", styling is in fact just one component of the design process. Typically, styling is developed through sketches, renderings and illustrations then realised in 3D form using automotive styling clay, specialised industrial modeling foams such as Sibatool, Renshape or Epiwood, or in increasingly limited cases plaster or body filler. As the most subjective part of the design process, the various members of the development team must depend heavily on the judgment, skill and experience of the appointed designer to create an appropriate look.\nThe most misunderstood element and the most dangerous to the success of a product, is the idea that team members should evaluate the design based on personal tastes or preferences. Industrial design is not an art form, but a focused creative expression using the scientific data and analysis in the Design Brief and QFD as ultimate guidelines. The target user, their needs and tastes should be reflected in the final design, not necessarily exclusively those of the design team. Of course, many complex variables such as the OEM brand identity, past successes and failures, and whimsical trends often skew or distort styling decisions. In instances where the factors are overwhelming, OEM's may err on the side of cautious conservative design.\nParallel development.\nBecause of the need to reduce development time and costs, the \"styling\" design model is usually developed in parallel with the engineering 3D design. While there is an increasing amount of digital design input in the modern OEM design process, nearly all major motorcycle manufacturers still rely on full scale clay models to render the master style model, then scan and import the styling surfaces into suitable 3D software packages (Alias, CATIA, ISEM Surf) for integration into the 3D engineering CAD platform (CATIA, ProEngineer, etc.). Once combined, the design team can virtually refine the motorcycle by optimising component assembly, checking for any undesirable interferences between parts, and predict and eliminate possible engineering problems. Typically, designers and engineers will have the greatest number of conflicts during this phase of development, as designers will fight to maintain the original styling and design of the clay model and artwork into the production vehicle, while the engineer will eliminate all problems in the most efficient manner possible. The success of the final product depends heavily on the level of cooperation between these often conflicting needs.\nAmateur and specialists.\nCustom builders.\nIn recent years, largely due to the popularity of television programs like \"Orange County Chopper\" and \"Biker Build-off\", the building of one of a kind \"chopper\" or \"cruiser\" type motorcycles has become more mainstream, leading to a flourishing builder industry. As a whole, these vehicles are not designed in the professional sense, but rather crafted by hand by metal workers and artisans using traditional skills. The resulting vehicles tend to be very elaborate, expensive and difficult or impossible to reproduce in mass production, but are highly valued for the same reasons.\nAmong custom motorcycle culture, certain names have become famous for their creations and have led to mainstream acceptance of previously unacceptable design solutions such as extreme ergonomics, totally rigid rear wheels without the benefit of suspension, minimal lighting and limited ground clearance for cornering. These design characteristics are purely emotional in nature, being led by styling and image rather than technical or performance considerations.\n\"Specials\".\nCustom and specials motorcycles are similar to the above but tend to be super sport type motorcycles, or at least high-performance based, using many special add-on parts, one-of-a-kind or limited series frames, racing wheels and parts or hand-made components to maximise performance. While modifying motorcycles is an activity as old as the motorcycle itself, the \"special\" culture or \"streetfighter\" began to flourish in the mid-1970s as a response to the myriad high performance Japanese motorcycles then available, but whose power far exceeded their handling. Individuals would choose premanufactured parts from catalogs or from other bikes and redesign their particular machine to suit their desires. In general this activity is limited to one-of-a-kind vehicles and, as with custom motorcycles, uses very little genuine engineering or design methodology, although some small-scale manufacturers exist who make limited runs of a given model. In some cases, these tiny specialists were successful enough to grow into full-scale OEM companies such as the Buell Motorcycle Company and Bimota of Italy.", "Engineering,_Manufacturing": 0.9977582097, "qwen": "Yes"}
{"id": "25313777", "revid": "43098031", "url": "https://en.wikipedia.org/wiki?curid=25313777", "title": "Fujitsu Computer Products of America", "text": "Fujitsu Computer Products of America, Inc. is a subsidiary of Fujitsu Limited, the world's third largest IT products and services provider. FCPA designs, develops, and manufactures innovative computer products for the global marketplace. Current product and service offerings include high-performance hard disk drives, scanners and scanner maintenance, palm vein recognition technology, and 10Gb Ethernet switches and degaussers. FCPA is headquartered in Sunnyvale, California, United States. The company is responsible for design and development, distribution, sales and marketing, finance and administration, and engineering and technical support for the Fujitsu document imaging scanner business and computing and storage products.\nThe company claims to have a \"55 percent market share in the U.S. of the 20-to-49-pages-per-minute, high-performance scanner market.\"\nList of FCPA product groups.\n\"Fujitsu sold its Enterprise Hard Disk Drive business to Toshiba as of October 1st, 2009.\"", "Engineering,_Manufacturing": 0.9988250732, "qwen": "Yes"}
{"id": "25324417", "revid": "46064651", "url": "https://en.wikipedia.org/wiki?curid=25324417", "title": "Welding defect", "text": "In metalworking, a welding defect is any flaw that compromises the usefulness of a weldment. There are many different types of welding defects. Welding defects are classified according to ISO 6520, while their acceptable limits are specified in ISO 5817 and ISO 10042.\nMajor causes.\nAccording to the American Society of Mechanical Engineers (ASME), causes of welding defects can be broken down as follows: 41% poor process conditions, 32% operator error, 12% wrong technique, 10% incorrect consumables and 5% bad weld grooves.\nResidual stresses.\nThe magnitude of stress that can be formed from welding can be roughly calculated using:\nWhere formula_2 is Young's modulus, formula_3 is the coefficient of thermal expansion, and formula_4 is the temperature change. This calculates approximately for steel.\nTypes.\nCracks.\nArc strikes.\nAn arc strike is a discontinuity resulting from an arc consisting of any localized remelted metal, heat-affected metal, or change in the surface profile of any metal object.\nArc strikes result in localized base metal heating and very rapid cooling. When located outside the intended weld area, they may result in hardening or localized cracking and may serve as potential sites for initiating fracture. In statically loaded structures, arc strikes need not be removed unless such removal is required in contract documents. However, in cyclically loaded structures, arc strikes may result in stress concentrations that would be detrimental to the serviceability of such structures, and arc strikes should be ground smooth and visually inspected for cracks.\nCold cracking.\nCold cracking, also known as delayed cracking, hydrogen-assisted cracking (HAC), or hydrogen-induced cracking (HIC), is a type of defect that often develops after solidification of the weld when the temperature starts to drop from about 190 °C (375 °F); the phenomenon often arises at room temperature, and it can take up to 24 hours to appear even after complete cooling. Some codes require testing on welded objects 48 hours after the welding process. This type of crack is usually observed in the heat affected zone (HAZ), especially for carbon steel which has limited hardenability. However, for other alloy steel with a high degree of hardenability, cold cracking could occur in both weld metal and the HAZ. This crack mechanism can also propagate between grains and through grains. Factors that can contribute to the occurrence of cold cracking are:\nThe alloy composition of the base metal also has an essential role in the likelihood of a cold crack since it relates to the hardenability of materials. With high cooling rates, the risk of forming a hard, brittle structure in the weld metal and HAZ is more likely. The hardenability of a material is usually expressed in terms of its carbon content or, when other elements are taken into account, it's carbon equivalent (CE) value.\nThen, depending on the carbon content (with additional elements resulting in the carbon equivalent index), steels can be classified into three zones from their cold cracking behavior as shown in Graville diagram.\nCrater crack.\nCrater cracks occur when a welding arc is broken, a crater will form if adequate molten metal is available to fill the arc cavity.\nHat crack.\nHat cracks get their name from the shape of the weld cross-section, because the weld flares out at the face of the weld. The crack starts at the fusion line and extends up through the weld. They are usually caused by too much voltage or not enough speed.\nHot cracking.\nHot cracking, also known as solidification cracking, can occur with all metals, and happens in the fusion zone of a weld. Excess material restraint should be avoided to diminish the probability of this type of cracking, and a proper filler material should be utilized. Other causes include too high welding current, poor joint design that does not diffuse heat, impurities (such as sulfur and phosphorus), preheating, speed is too fast, and long arcs.\nUnderbead crack.\nAn underbead crack, also known as a heat-affected zone (HAZ) crack, is a crack that forms a short distance away from the fusion line; it occurs in low alloy and high alloy steel. The exact causes of this type of crack are not entirely understood, but it is known that dissolved hydrogen must be present. The other factor that affects this type of crack is internal stresses resulting from: unequal contraction between the base metal and the weld metal, restraint of the base metal, stresses from the formation of martensite, and highlights from the precipitation of hydrogen out of the metal.\nLongitudinal crack.\nLongitudinal cracks run along the length of a weld bead. There are three types: \"check cracks\", \"root cracks\", and \"full centerline cracks\". Check cracks are visible from the surface and extend partially into the weld. They are usually caused by high shrinkage stresses, especially on final passes, or by a hot cracking mechanism. Root cracks start at the root and extent part-way into the weld. They are the most common type of longitudinal crack because of the small size of the first weld bead. If this type of crack is not addressed, it will usually propagate into subsequent weld passes, which is how full cracks (a crack from the root to the surface) usually form.\nReheat cracking.\nReheat cracking is a type of cracking that occurs in HSLA steels, particularly chromium, molybdenum and vanadium steels, during post-heating. The phenomenon has also been observed in austenitic stainless steel. The poor creep ductility of the heat-affected zone causes it. Any existing defects or notches aggravate crack formation. Things that help prevent reheat cracking include heat treating first with a low-temperature soak and then with rapid heating to high temperatures, grinding or peening the weld toes, and using a two-layer welding technique to refine the HAZ grain structure.\nRoot and toe cracks.\nA root crack is formed by the short bead at the root(of edge preparation) beginning of the welding, low current at the beginning, and due to improper filler material used for welding. The primary reason for these types of cracks is hydrogen embrittlement. These defects can be eliminated using a high current at the starting and proper filler material. Toe crack occurs due to moisture content in the welded area; it is a part of the surface crack so that it can be easily detected. Preheating and proper joint formation are a must for eliminating these types of defects.\nTransverse crack.\nTransverse cracks are perpendicular to the direction of the weld. These are generally the result of longitudinal shrinkage stresses acting on weld metal of low ductility. Crater cracks occur in the crater when the welding arc is terminated prematurely. Crater cracks are typically shallow, hot cracks, usually forming single or star cracks. These cracks usually start at a crater pipe and extend longitudinally in the crater. However, they may propagate into longitudinal weld cracks in the rest of the weld.\nDistortion.\nWelding methods that involve the melting of metal at the site of the joint necessarily are prone to shrinkage as the heated metal cools. Shrinkage then introduces residual stresses and distortion. Distortion can pose a major problem since the final product is not the desired shape. To alleviate certain types of distortion, the workpieces can be offset so that after welding, the product is the correct shape. The following pictures describe various types of welding distortion:\nGas inclusion.\nGas inclusions are a wide variety of defects, including \"porosity\", \"blow holes\", and \"pipes\" (or \"wormholes\"). The underlying cause for gas inclusions is gas entrapment within the solidified weld. Gas formation can be from any of the following causes- high sulphur content in the workpiece or electrode, excessive moisture from the electrode or workpiece, too short of an arc, or wrong welding current or polarity.\nInclusions.\nThere are two types of inclusions: \"linear inclusions\" and \"rounded inclusions\". Inclusions can be either \"isolated\" or \"cumulative\". Linear inclusions occur when there is slag or flux in the weld. Slag forms from the use of a flux, which is why this type of defect usually occurs in welding processes that use flux, such as shielded metal arc welding, flux-cored arc welding, and submerged arc welding, but it can also occur in gas metal arc welding. This defect usually occurs in welds that require multiple passes, and there is poor overlap between the welds. The poor overlap does not allow the slag from the previous weld to melt out and rise to the top of the new weld bead. It can also occur if the previous weld left an undercut or an uneven surface profile. To prevent slag inclusions, the slag should be cleaned from the weld bead between passes via grinding, wire brushing, or chipping.\nIsolated inclusions occur when rust or mill scale is present on the base metal.\nLack of fusion and incomplete penetration.\nLack of fusion is the poor adhesion of the weld bead to the base metal; incomplete penetration is a weld bead that does not start at the root of the weld groove. Incomplete penetration forms channels and crevices in the root of the weld, which can cause serious issues in pipes because corrosive substances can settle in these areas. These types of defects occur when the welding procedures are not adhered to; possible causes include the current setting, arc length, electrode angle, and electrode manipulation. Defects can be varied and classified as critical or noncritical. Porosity (bubbles) in the weld are usually acceptable to a certain degree. Slag inclusions, undercut, and cracks are usually unacceptable. Some porosity, cracks, and slag inclusions are visible and may not need further inspection to require their removal. Liquid Penetrant Testing (Dye check) can verify minor defects. Magnetic Particle Inspection can discover Slag inclusions and cracks just below the surface. Deeper defects can be detected using Radiographic (X-rays) and/or Ultrasound (sound waves) testing techniques.\nLamellar tearing.\nLamellar tearing is a type of welding defect that occurs in rolled steel plates that have been welded together due to shrinkage forces perpendicular to the faces of the plates. Since the 1970s, changes in manufacturing practices limiting the amount of sulfur used have greatly reduced the incidence of this problem.\nLamellar tearing is caused mainly by sulfurous inclusions in the material. Other causes include excess hydrogen in the alloy. This defect can be mitigated by keeping the amount of sulfur in the steel alloy below 0.005%. Adding rare earth elements, zirconium, or calcium to the alloy to control the configuration of sulfur inclusions throughout the metal lattice can also mitigate the problem.\nModifying the construction process to use cast or forged parts in place of welded parts can eliminate this problem, as Lamellar tearing only occurs in welded parts.\nUndercut.\nUndercutting is when the weld reduces the base metal's cross-sectional thickness and reduces the strength of the weld and workpieces. One reason for this type of defect is excessive current, causing the edges of the joint to melt and drain into the weld; this leaves a drain-like impression along the length of the weld. Another reason is if a poor technique is used that does not deposit enough filler metal along the edges of the weld. A third reason is using an incorrect filler metal, which will create greater temperature gradients between the center of the weld and the edges. Other causes include too small of an electrode angle, a dampened electrode, excessive arc length, and slow speed.", "Engineering,_Manufacturing": 0.9999141693, "qwen": "Yes"}
{"id": "16066056", "revid": "35936988", "url": "https://en.wikipedia.org/wiki?curid=16066056", "title": "Digital modeling and fabrication", "text": "Digital modeling and fabrication is a design and production process that combines 3D modeling or computing-aided design (CAD) with additive and subtractive manufacturing. Additive manufacturing is also known as 3D printing, while subtractive manufacturing may also be referred to as machining, and many other technologies can be exploited to physically produce the designed objects. \nModeling.\nDigitally fabricated objects are created with a variety of CAD software packages, using both 2D vector drawing, and 3D modeling. Types of 3D models include wireframe, solid, surface and mesh. A design has one or more of these model types.\nMachines for fabrication.\nThree machines are popular for fabrication:\n1. CNC router\n2. Laser cutter\n3. 3D Printer\nCNC milling machine.\nCNC stands for \"computer numerical control\". CNC mills or routers include proprietary software which interprets 2D vector drawings or 3D models and converts this information to a G-code, which represents specific CNC functions in an alphanumeric format, which the CNC mill can interpret. The G-codes drive a machine tool, a powered mechanical device typically used to fabricate components. CNC machines are classified according to the number of axes that they possess, with 3, 4 and 5 axis machines all being common, and industrial robots being described with having as many as 9 axes. CNC machines are specifically successful in milling materials such as plywood, plastics, foam board, and metal at a fast speed. CNC machine beds are typically large enough to allow 4' × 8' (123 cm x 246 cm) sheets of material, including foam several inches thick, to be cut.\nLaser cutter.\nThe laser cutter is a machine that uses a laser to cut materials such as chip board, matte board, felt, wood, and acrylic up to 3/8 inch (1 cm) thickness. The laser cutter is often bundled with a driver software which interprets vector drawings produced by any number of CAD software platforms.\nThe laser cutter is able to modulate the speed of the laser head, as well as the intensity and resolution of the laser beam, and as such is able in both to cut and to score material, as well as approximate raster graphics.\nObjects cut out of materials can be used in the fabrication of physical models, which will only require the assembly of the flat parts.\n3D printers.\n3D printers use a variety of methods and technology to assemble physical versions of digital objects. Typically desktop 3D printers can make small plastic 3D objects. They use a roll of thin plastic filament, melting the plastic and then depositing it precisely to cool and harden. They normally build 3D objects from bottom to top in a series of many very thin plastic horizontal layers. This process often happens over the course of several hours. \nFused deposition modeling.\nFused deposition modeling, also known as fused filament fabrication, uses a 3-axis robotic system that extrudes material, typically a thermoplastic, one thin layer at a time and progressively builds up a shape. Examples of machines that use this method are the Dimension 768 and the Ultimaker.\nStereolithography.\nStereolithography uses a high intensity light projector, usually using DLP technology, with a photosensitive polymer resin. It will project the profile of an object to build a single layer, curing the resin into a solid shape. Then the printer will move the object out of the way by a small amount and project the profile of the next layer. Examples of devices that use this method are the Form-One printer and Os-RC Illios.\nSelective laser sintering.\nSelective laser sintering uses a laser to trace out the shape of an object in a bed of finely powdered material that can be fused together by the application of heat from the laser. After one layer has been traced by a laser, the bed and partially finished part is moved out of the way, a thin layer of the powdered material is spread, and the process is repeated. Typical materials used are alumide, steel, glass, thermoplastics (especially nylon), and certain ceramics. Example devices include the Formiga P 110 and the Eos EosINT P730.\nPowder printer.\nPowder printers work in a similar manner to SLS machines, and typically use powders that can be cured, hardened, or otherwise made solid by the application of a liquid binder that is delivered via an inkjet printhead. Common materials are plaster of paris, clay, powdered sugar, wood-filler bonding putty, and flour, which are typically cured with water, alcohol, vinegar, or some combination thereof. The major advantage of powder and SLS machines is their ability to continuously support all parts of their objects throughout the printing process with unprinted powder. This permits the production of geometries not easily otherwise created. However, these printers are often more complex and expensive. Examples of printers using this method are the ZCorp Zprint 400 and 450.", "Engineering,_Manufacturing": 1.0000060797, "qwen": "Yes"}
{"id": "22344034", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=22344034", "title": "Supply chain sustainability", "text": "Supply-chain sustainability is the impact a company’s supply chain can make in promoting human rights, fair labor practices, environmental progress and anti-corruption policies. There is a growing need for integrating sustainable choices into supply-chain management. An increasing concern for sustainability is transforming how companies approach business. Whether motivated by their customers, corporate values or business opportunity, traditional priorities such as quality, efficiency and cost regularly compete for attention with concerns such as working conditions and environmental impact. A sustainable supply chain seizes value chain opportunities and offers significant competitive advantages for early adopters and process innovators.\nBackground.\nSupply chains are critical links that connect an organization’s inputs to its outputs. Traditional challenges have included lowering costs, ensuring just-in-time delivery, and shrinking transportation times to allow better reaction to business challenges. However, the increasing environmental, social and economic costs of these networks and growing consumer pressure for eco-friendly products has led many organizations to look at supply chain sustainability as a new measure of profitable logistics management. This shift is reflected by an understanding that sustainable supply chains mean profitable supply chains.\nMany companies are limited to measuring the sustainability of their own business operations and are unable to extend this evaluation to their suppliers and customers. This makes determining their true environmental and social costs highly challenging. However much progress has been made in defining supply chain sustainability and benchmarking tools are now available that enable sustainability action plans to be developed and implemented. A study conducted in 2017 researched the correlation between supply chain position (how close or far the firm is from the end user in the supply chain) and firm performance. The study findings concluded that suppliers located farther upstream in the supply chain (farther from the end user), had the most to gain financially from sustainable supply chain management.\nEnvironmental impact.\nClimate change poses a new risk to supply chains and a need to increase their resilience. As companies are setting carbon footprint targets, suppliers’ operations are responsible for 65% to 95% of a company’s total emissions. These environmental impacts are evident across industries, for example, food and beverage companies are particularly vulnerable to the impacts of climate change as changing weather patterns can disrupt agricultural production. Measuring supply chain resilience on factors such as natural resource availability, infrastructure, financial resources, and social safety networks among others, can help them respond to challenges and create better supply chains in the process.\nSocial impact.\nBesides sustainability and resilience, an ethical supply chain is imperative to ensure corporate social responsibility and adhere to a supplier code of conduct. The work environment for the workers should be congenial and must not violate the basic human rights. For instance, companies like Nike and Apple, which outsource manufacturing of their products to other countries like China, have been under the scanner for workplace conditions and wages of their workers. Consumers increasingly demand transparency and traceability in supply chains, especially where disturbing social breakdowns occur, such as with forced labour and child labour for globally traded goods.\nForced labor, understood as work that is performed involuntarily or under coercion, occurs in different industries, often upstream in the supply chain with limited visibility to buyers, customers, and end-users.\nFor example, in the United States, the 2010 Dodd–Frank Wall Street Reform and Consumer Protection Act requires manufacturers to audit their supply chains and report use of conflict minerals to the Securities and Exchange Commission.\nGovernance impact.\nGovernance practices in global supply chains can pose risks to supply chain sustainability, alongside social and environmental factors. Governance factors include guidelines and procedures for countries and corporations. Buyers screen their supply chains for appropriate governance practices such as a company’s purpose, the role and makeup of boards of directors, shareholder rights and how corporate performance is measured.\nStakeholders.\nThe purchasing power held by buyers, gives them significant influence over their vendors or suppliers’ business practices. Companies in the role of buyers acquire goods or services through organizational functions such as purchasing, procurement, or sourcing, typically for use or consumption in their own organization. Suppliers or vendors typically sell their goods or services to the next link in the supply chain. Buyers might thus interface with only one tier of their suppliers, while their supply chain spans across complex tiers of suppliers upstream. Progress has been made in the sustainable procurement space as companies help suppliers design and implement sustainability programs that directly support the companies’ own goals. Buyers are working to achieve sustainability goals by setting standards for their suppliers’ performance and treating sustainability performance similar to other business considerations such as cost, quality, and timeliness.\nOne of the key requirements of successful sustainable supply chains is collaboration. The practice of collaboration — such as sharing distribution to reduce waste by ensuring that half-empty vehicles do not get sent out and that deliveries to the same address are on the same truck — is not widespread because many companies fear a loss of commercial control by working with others. Investment in alternative modes of transportation — such as use of canals and airships — can play an important role in helping companies reduce the cost and environmental impact of their deliveries.\nDrivers for supply chain sustainability.\nAs of 2021, a growing number of companies see supply chain sustainability as a strategic business matter. A business strategy for supply chain environmental performance can deliver measurable environmental benefits for the company and its stakeholders. A sustainable sourcing strategy positions the company for increasing demands of higher disclosure and investor scrutiny, more environmentally focused consumers, and scarce resources. Sustainable procurement is a key concern for investors, through movements such as socially responsible investing. Leading investment firms such as BlackRock use their influence to bring supply chain sustainability on the agenda. Customers and consumers also demand supply chain responsibility and sustainability as part of a company’s value proposition under a growing ethical consumerism movement. Consumers’ purchasing behaviors reflect this trend as 70% say they are willing to pay a 5% price premium for products produced by more-sustainable means. During global supply chain disruptions following the COVID-19 pandemic, sustainable supply chains have been shown to be more resilient and have lower supplier risk.\nApplication of supply chain sustainability.\nCompanies looking to implement sustainable strategies down its supply chain should also look upstream. To elaborate, if a company is able to choose between various suppliers, it can for example use its purchasing power to get its suppliers in compliance with its green supply chain standards. In managing suppliers, companies must measure that inputs from suppliers are of high quality, and the usage of water and energy is minimized leading to less pollution, defects and over production. They also must audit their supplier base and make sure that they are improving the supply chain metrics\nWhen measuring sustainability in supply chains, consistent measurements which can be replicated and compared are crucial to encourage consumer trust. Environmental and social change often takes time to measure and must be considered by private companies or governments over a long term period to accurately assess the results. Some companies utilize supplier scorecards to determine suppliers’ sustainability performance.  This can be accomplished by conducting life-cycle assessments or surveys to help determine their sustainability practices. Another strategy is to award suppliers for their improvement on their sustainability performance, for instance, by developing new materials sourced from waste or by making operations more energy efficient.\nSoftware.\nDigital technology has increased companies’ capability to collaborate with large numbers of suppliers. As supply-chain sustainability becomes a more critical business issue, the need for reliable and robust data from suppliers increases. Whilst some existing business systems can collect some sustainability data, most large businesses will look to dedicated software providers for more specific sustainability functionality.\nIn order for businesses to determine the degree of sustainability impact of their business model, they must have the data to support it. Harvard Business School created the Impact-Weighted Accounts Initiative (IWAI) to assess the degree of impact that many large companies have on social, environmental, and economic areas. Impact data comes from long term research on specific, measurable topics that can be applied to future changes within a company or system. Impact data is often more sparse or inaccessible than it should be, which allows institutions such as HBS to hold companies accountable in their supply chains and encourage greater transparency. Transparency in the supply chain influences how consumers view and support companies, so improving data driven sustainability efforts can positively affect supply chain business. A company’s negative impact on environmental or social areas may show in their stock market value, exposing their true values to investors. While impact data is probably one of the better ways of assessing a company’s long term impacts, it is important to note that data collection for impact assessment is a lengthy process and not all companies can spend long periods of time measuring their impact without making changes. Because of this, simple, credible alternatives to long term impact assessments are necessary for some businesses.\nOn-site audits.\nIn addition to digital tools, on-site audits can be an effective tool to verify social and environmental compliance at supplier sites. On-site audits can certify a supplier’s compliance with an external standard, such as SA8000, ISO 14001, SMETA 4-Pillar, and others. Audits can also assess compliance with internal policies and guidelines set by a business partner, for example through a supplier code of conduct. Depending on the auditing standard, buyers might choose to audit their suppliers directly, or send auditors from a third-party auditing firm to supplier sites.\nChallenges in achieving supply chain sustainability goals.\nDespite companies being increasingly focused on working with suppliers that help them achieve their sustainability goals, challenges continue to persist. Suppliers further up the supply chain generally lack the maturity, tools, and capabilities to manage and drive environmental and social improvements. When faced with workplace issues such as sexual harassment, retaliation by superiors, and a hazardous environment, lower tiered suppliers typically have a poor response plan, or no plan at all. In cases where a plan is established, suppliers are unable to implement it and train their employees accordingly due to a workforce consisting of nearly 50% temporary workers. As you move further upstream in the supply chain, a company loses more oversight over suppliers. Companies do not directly operate with lower tiered suppliers, and there is generally no contractual relationship in place between the two. This makes it increasingly difficult for companies to manage sustainability upstream. Additionally, lower tiered suppliers operate in relative obscurity compared to the companies they supply, so they tend not to face the same level of scrutiny if failing to meet sustainability standards.  \nMany companies have thousands of suppliers, making it difficult for those in charge of driving supply chain sustainability to know where to begin and focus their efforts. They may not have access to the right data or may lack the authority to effect real change. Additionally, in striving to be more socially responsible, a company can inadvertently make it harder for smaller, diverse suppliers to compete with the larger, more established ones. Generally, the larger suppliers are better equipped to drive sustainability improvements compared with smaller ones. In rewarding the larger suppliers with larger contracts and reducing business or even severing ties with the smaller ones to achieve sustainability goals, companies make their supplier base less diverse and put the smaller suppliers at a disadvantage.", "Engineering,_Manufacturing": 0.9907810688, "qwen": "Yes"}
{"id": "22366353", "revid": "41438237", "url": "https://en.wikipedia.org/wiki?curid=22366353", "title": "CNC router", "text": "A computer numerical control (CNC) router is a computer-controlled cutting machine which typically mounts a hand-held router as a spindle which is used for cutting various materials, such as wood, composites, metals, plastics, glass, and foams. CNC routers can perform the tasks of many carpentry shop machines such as the panel saw, the spindle moulder, and the boring machine. They can also cut joinery such as mortises and tenons.\nA CNC router is very similar in concept to a CNC milling machine. Instead of routing by hand, tool paths are controlled via computer numerical control. The CNC router is one of many kinds of tools that have CNC variants.\nApplications.\nA CNC router can be used to produce items such as door carvings, interior and exterior decorations, wood panels, sign boards, wooden frames, moldings, musical instruments, furniture. In addition, they see use in industry in the thermoforming of plastics by automating the trimming process. CNC routers can help ensure part repeatability and sufficiently efficient output for production, or allow one-off designs to be made.\nUse.\nCNC routers are controlled by a computer. Coordinates are uploaded into the machine controller from a separate program. CNC router are often used with two software applications—one to make designs (CAD) and another to translate those designs into a G-code or M-code program of instructions for the machine (CAM) in vertical, horizontal and perpendicular coordinates. As with CNC milling machines, CNC routers can be controlled directly by manual programming, but CAD/CAM allows wider possibilities for contouring, speeding up the programming process and in some cases creating programs whose manual programming would be impractical. On some controllers the G-code can be loaded as a vector file on the router control panel. A vector file can be created from a picture file by using a drawing (CAD) software.\nThe human operator selects the machine tool (such as a -inch (6-MM) v-bit or a -inch core box bit), speed, cut depth and tool path. For cut path, most machines give the options of tracing the vectors, cutting outside the vectors, or cutting inside the vectors. The operator determines the center point of the part, clamps the part onto the table, moves the bit directly above the marked center and down to the face of the part, and marks this as the starting point. The operator moves the bit up a few inches and selects the run G-code function. The machine begins to cut the design.\nComputer-aided manufacturing.\nCAM software makes the CAD drawing/design into a code called G-code. The illustration shows what a bare-bones CNC machine might look like without its computer controller.\nSizes and configurations.\nCNC routers come in many configurations, from small home-style D.I.Y. \"desktop\", to large industrial routers manufactured for commercial use. CNC routers are used in sign shops, cabinet making, aerospace and boat-making.\nAlthough there are many configurations, most CNC routers have a few specific parts: a dedicated CNC controller, one or more spindle motors, servo motors or stepper motors, servo amplifiers, AC inverter frequency drives, linear guides, ball screws and a workspace bed or table.\nIn addition, CNC routers may have accessories such as vacuum pumps, with grid table tops or t-slot hold down fixtures to hold the parts in place for cutting. CNC routers are typically available in 3-axis and 5-axis CNC formats. Many manufacturers offer A and B axis for full 5-axis capabilities and rotary 4th axis. Common industrial CNC router sizes include 4 × 8 feet and 5 × 10 feet.\nMany CNC routers today are made of aluminum extrusion which provide great flexibility as this can be shipped from almost anywhere unassembled but also provides size options. Some popular extrusion used are MakerSlide, V-Slot linear rail, and 8020 T-Slotted profile.\nMaterials.\nWood.\nA CNC wood router is a computer-controlled router tool that carves/etches objects or images into the face of a piece of wood. The CNC Router is ideal for hobbies, engineering prototyping, product development, art, and production works. The CNC works on the Cartesian coordinate system (X, Y, Z) for 3D motion control; however, typical CNC operated systems can only make carvings on flat planes. The machine sits on a track and is not capable of making round or spherical cuts. Parts of a project can be designed in the computer with a CAD/CAM program, and then cut automatically using a router or other cutters to produce a finished part. In some instances, the table will not come with a router included. This allows the user to change out routers for different applications. For lighter strained cuts, they could use a lower grade router but for more intensive applications.\nMetal.\nMilling is the machining process of using rotary cutters to remove material from a workpiece advancing (or \"feeding\") in a direction at an angle with the axis of the tool. It covers a wide variety of operations and machines, on scales from small individual parts to large, heavy-duty gang milling operations. It is one of the most commonly used processes in industry and machine shops today for machining parts to precise sizes and shapes.\nStone.\nA stone CNC router is a type of CNC router machine designed for marble, granite, artificial stone, tombstone, ceramic tiles, glass machining, polishing for arts and crafts, etc. Wood, metal and stone require different \"bits\" or \"inserts\". There is bit call as diamond tools with different diameter 4mm, 6mm, 8mm mainly used. For wood CNC-ing, bits with sharp cutting edges are used, while for Stone CNC-ing, the bits are made of a metal bar with a sintered layer of extremely hard but roughly shaped particles. Routing CNC is more like grinding than cutting.\nBecause stone dust is very abrasive, these routers also have much better protection for the guide rails(below cover). With \"wood\" routers the guide rails are often visible from the outside & unprotected, while stone routers are fully covered.\nStone routers also have a water recirculation system. A small jet of water is pointed at the router bit and this captures almost all fine stone dust in the water, which then flows to a collection reservoir where the stone particles settle on the bottom.\nPolyurethane foam.\nPolyurethane foam can also be cut using a CNC router in order to produce complex shapes which would otherwise be difficult or impossible to replicate by hand. Depending on the type of foam being converted, a CNC router would be able to cut through up to an 8lb density. By converting a CAD design file into a CAM file, the CNC Router is able to read relevant information and produce a highly accurate finished product.", "Engineering,_Manufacturing": 0.9963025451, "qwen": "Yes"}
{"id": "9748706", "revid": "139104", "url": "https://en.wikipedia.org/wiki?curid=9748706", "title": "Keystone module", "text": "A keystone module is a standardized snap-in package for mounting a variety of low-voltage electrical jacks or optical connectors into a keystone wall plate, face plate, surface-mount box, or a patch panel.\nKeystone modules have a rectangular face of 14.5 mm wide by 16.0 mm high and are held in place with flexible tabs. This allows them to be snapped into a mounting plate with correspondingly-sized rectangular holes, called ports. Most keystones are interchangeable and replaceable. This provides much flexibility in arranging and mounting many different types of electrical jacks in one plate or panel without requiring customized manufacturing.\nSome keystones use a pass-through type connector, where there is a jack on both the front face and the rear side. Others only have a jack on the front and employ a different mechanism for hard-wiring signal cables to the rear, such as a mini 110 block, an insulation-displacement connector, or a crimp or solder connection.\nTypes of modules available.\nMany types of jacks are available in the keystone module format, limited mainly by their physical size, including:\nHistory.\nThe origin of the \"Keystone\" module may be traced back to US Patent 4261633 of Aug 27, 1979 for a \"Wiring module for telephone jack\" - by Amp Incorporated.\nThe module referred to in that patent was affixed by \"A pair of diagonally inclined mounting flanges (which) include stepped, panel bearing surfaces .. at the outer free ends thereof.\" The unit was \"inserted through the panel opening, with the sides of the opening resiliently deflecting the (mounting flanges), until they pass through the opening and spring outwardly away from the remainder of the housing, with the panel bearing surfaces .. thereof seated against the front surface of the panel\".\nHowever, the current design (now called \"Keystone\") is first referenced in US Patent US 5624274 of Nov 7, 1995 for a \"Telephone connector with contact protection block\" - by International Connectors And Cable Corporation. In this design the module is affixed by a single diagonally inclined mounting flange, together with a protuberance (ramp) on the opposite side. In the patent description, it is stated that \"the jack assembly may be mounted to a face plate by first inserting the bottom of the jack assembly into a jack opening until the ramp of the housing engages a mounting surface of the face plate. The jack assembly is then rotated and snapped into place due to deflection of the cantilever latch of the housing.\"", "Engineering,_Manufacturing": 0.9998171926, "qwen": "Yes"}
{"id": "9749408", "revid": "1141151061", "url": "https://en.wikipedia.org/wiki?curid=9749408", "title": "Work order", "text": "A work order is usually a task or a job for a customer, that can be scheduled or assigned to someone. Such an order may be from a customer request or created internally within the organization. Work orders may also be created as follow ups to inspections or audits. A work order may be for products or services.\nA work order should include the following: \nIn a manufacturing environment, a work order is converted from a sales order to show that work is about to begin on the manufacture, building or engineering of the products requested by the customer. In a service environment, a work order can be equivalent to a service order where the WO records the location, date and time the service is carried out and the nature of work that is done. The type of personnel (e.g. job position) may also be listed on the WO. A rate (e.g. $/hr, $/week) and also the total number of hours worked and total value is also shown on the work order.\nA work order may be a maintenance or repair request from students, faculty or staff in a university.\nOrders received from outside an organization are often dispatched (reviewed and scheduled) before being executed. Work orders may be for preventive maintenance\nContractors may use a single job work order and invoice form that contains the customer information, describes the work performed, lists charges for material and labor, and can be given to the customer as an invoice.\nA job order is an internal document extensively used by projects-based, manufacturing, building and fabrication businesses. A job order may be for products and/or services. In a manufacturing environment, a job order is used to signal the start of a manufacturing process and will most probably be linked to a bill of material. Hence, the job order will probably state:\nIn a service environment, a job order cannot be the equivalent to a work or service order where the job order records the location, date and time the service is carried out and the nature of service that was carried out, the work order does not. The type of personnel (e.g. job position) may also be listed on the job order. A rate (e.g. $/hr, $/week) and also the total number of hours worked and total value is also shown.", "Engineering,_Manufacturing": 0.999953866, "qwen": "Yes"}
{"id": "23006613", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=23006613", "title": "X-Y table", "text": "X-Y tables, also known as cross working tables or coordinate tables, help provide horizontal motion for automated machinery such as assembly robots in manufacturing facilities. Robotic arms and other automated machinery have only a limited range of motion while their bases remain stationary; X-Y tables allow these basis to move horizontally along X and Y axis. Also known as XY stages, XY tables are motorized linear slides with linear motion based in bearings which are driven by a drive mechanism, typically a linear motor. XY tables are built and configured to provide high-performance positioning along multiple axis.\nApplications.\nServing industries including general machinery, pharmaceutical, manufacturing and semiconductor, XY tables offer precision-controlled automated movement. XY tables are broadly used in mechanical processes and applications including material handling, industrial automation equipment, machinery building and automated measurement.\nConstruction.\nXY tables are flat surfaces mounted on ball bearing slides or roller slides with multiple linear bases and are composed of forcers and platens. The forcer glides over the platen on frictionless air bearings and moves continuously in a linear motion across the platen. To create multiple axis, linear bases are often stacked on top of one another, with the top \"Y\" axis acting both as a carriage to the bottom base and as the base which holds the table. Adjustable gibs can be attached on both axis. These types of XY tables, used frequently for the movement of robotic, are often called \"positioning tables\". Materials used to construct XY tables include stainless steel and cast iron as well as bronze for bearings and aluminum for frames.\nTypes.\nVariations among XY tables include the ways and the drive mechanism. The ways determine load capacity, straight-line accuracy, and stiffness, or durability, while the drive mechanisms determine smoothness and speed. In general, XY tables require very little maintenance, and are considered to be highly accurate, easy-to-use and lightweight. However, depending on the weight of the load, ball bearings within XY ball bearing tables and slides can acquire a significant amount of wear and may need to be replaced regularly.", "Engineering,_Manufacturing": 1.0000033379, "qwen": "Yes"}
{"id": "34162791", "revid": "1170122400", "url": "https://en.wikipedia.org/wiki?curid=34162791", "title": "Small-outline transistor", "text": "A small outline transistor (SOT) is a family of small footprint, discrete surface mount transistor commonly used in consumer electronics. The most common SOT are SOT23 variations. SOT23-3 differs from SOT23 in a wider body of 1.6mm instead on 1.3mm, also manufacturers offer the nearly identical thin small outline transistor (TSOT) package, where lower height is important. \nSOT23, SOT323, SOT416.\nThe SOT23 package is very popular and a common package for transistors, and is also used for diodes and voltage regulators.\nSOT54.\nSOT54 is an alternate designation for the JEDEC TO-92 package.\nSOT89-3.\nThe SOT89-3 electrically only has three leads (contact/pin). The wide lead (tab) is physically part of the middle lead on the other side of the package. Some call this package a SOT89-4, since it visually appears to have four leads when looking down at the part.\nSOT89-5.\nThe SOT89-5 electrically only has five leads (contact/pin). The middle lead is physically part of the middle lead on the other side of the package. Some call this package a SOT89-6, since it visually appears to have six leads when looking down at the part.\nSOT223 (SOT223-4).\nThe SOT223-4 package is a popular package for voltage regulators. It was introduced by Philips.\nSOT223-5.\nThe SOT223-5 package is a popular package for voltage regulators.\nSOT223-8.\nThe SOT223-8 package is a popular package for bridged quad transistors.", "Engineering,_Manufacturing": 0.9999520779, "qwen": "Yes"}
{"id": "1751119", "revid": "32718076", "url": "https://en.wikipedia.org/wiki?curid=1751119", "title": "Final good", "text": "A final good or consumer good is a final product ready for sale that is used by the consumer to satisfy current wants or needs, unlike an intermediate good, which is used to produce other goods. A microwave oven or a bicycle is a final good, but the parts purchased to manufacture them are intermediate goods.\nWhen used in measures of national income and output, the term \"final goods\" includes only new goods. For example, gross domestic product (GDP) excludes items counted in an earlier year to prevent double counting based on resale of items. In that context, the economic definition of goods also includes what are commonly known as \"services\".\nManufactured goods are goods that have been processed in any way. They are distinct from raw materials but include both intermediate goods and final goods.\nLaw.\nThere are legal definitions. For example, the United States' Consumer Product Safety Act has an extensive definition of consumer product, which begins:\nCONSUMER PRODUCT.--The term ‘‘consumer product’’ means any article, or component part thereof, produced or distributed (i) for sale to a consumer for use in or around a permanent or temporary household or residence, a school, in recreation, or otherwise, or (ii) for the personal use, consumption or enjoyment of a consumer in or around a permanent or temporary household or residence, a school, in recreation, or otherwise; but such term does not include—\n(A) any article which is not customarily produced or distributed for sale to, or use or consumption by, or enjoyment of, a consumer,\nIt then goes on to list eight additional specific exclusions and further details.\nDurability.\nFinal goods can be classified into the following categories:\nConsumer durable goods usually have a significant lifespan, which tends to be at least one year, based on the guarantee or warranty period. The maximum life depends upon the durability of the product or goods. Examples include tools, cars, and boats. On the other hand, capital goods, which are tangible in nature, such as machinery or building or any other equipment that can be used in manufacturing of final product, are durable goods with limited lifespans that are determined by manufacturers before their sale. The longevity and the often-higher cost of durable goods usually cause consumers to postpone expenditures on them, which makes durables the most volatile (or cost-dependent) component of consumption.\nConsumer nondurable goods are purchased for immediate use or for use very soon. Generally, the lifespan of nondurable goods is from a few minutes to up to three years: food, beverages, clothing, shoes and gasoline are examples. In everyday language, nondurable goods get consumed or \"used up\".\nConsumer services are intangible in nature. They cannot be seen, felt or tasted by the consumer but still give satisfaction to the consumer. They are also inseparable and variable in nature: they are thus produced and consumed simultaneously. Examples are haircuts, medical treatments, auto repairs and landscaping.\nBuying habits.\nFinal goods can be classified into the following categories, which are determined by consumers' buying habits:\nConvenience goods, shopping goods, and specialty goods are also known as \"red goods\", \"yellow goods\", and \"orange goods\", respectively, under the yellow, red and orange goods classification system.\nConvenience goods.\nConvenience goods are regularly consumed and easily available. Generally, convenience goods come in the category of nondurable goods such as fast foods, cigarettes and tobacco with low value. Convenience goods are sold mostly by wholesalers or retailers to make them available to the consumers in goods or large volume. Convenience goods can further be divided into staple convenience consumer goods and impulse convenience consumer goods.\nStaple convenience consumer goods are the basic necessities of the consumer. These goods are easily available and in large quantity: milk, bread, sugar, etc.\nImpulse convenience consumer goods do not belong to the priority list of the consumer. They are purchased without any prior planning, just on the basis of the impulse: potato wafers, candies, ice creams, cold drinks, etc.\nShopping consumer goods.\nShopping consumer goods are the goods which take lot of time and proper planning before making purchase decision; in this case consumer does a lot of selection and comparison based on various parameters such as cost, brand, style, comfort etc., before buying an item. Shopping goods are costlier than convenience goods and are durable in nature. Consumer goods companies usually try to set up their shops and show rooms in active shopping areas to attract customer attention and their main focus is to do much advertising and promotion to attract more customers.\nExamples include clothing items, televisions, radios, footwear, home furnishings, etc.\nSpecialty consumer goods.\nSpecialty goods are unique in nature; these are unusual and luxurious items available in the market. Specialty goods are mostly purchased by the upper classes of society as they are expensive in nature and difficult to afford for the middle and lower classes. Companies advertise their goods targeting the upper class. These goods do not fall under the category of necessity; rather they are purchased on the basis personal preference or desire. Brand name, uniqueness, and special features of an item are major attributes which attract customers and make them buy such products.\nExamples include antiques, jewelry, wedding dresses, cars, etc.\nUnsought consumer goods.\nUnsought goods belong to neither the necessity group of consumer goods list nor to specialty goods. They are always available in the market but are purchased by very few consumers, either based on their interest or their need for some specific reasons. The general public does not purchase such goods often.\nExamples include snowshoes, fire extinguishers, flood insurance, etc.\nMergers and acquisitions.\nIn the consumer product sector, there have been 107,891 deals announced between 1985 and 2018, which cumulates to a total value of around US$5,835 billion. 2007 was the year with the largest value (US$4,888 billion) followed by a steep slump in 2009 (-70.9%). After the first wave in 2007, now is the second big M&A wave in the consumer products sector, and a decline is expected.", "Engineering,_Manufacturing": 0.9859781265, "qwen": "Yes"}
{"id": "1752442", "revid": "36529075", "url": "https://en.wikipedia.org/wiki?curid=1752442", "title": "Integrated device manufacturer", "text": "An integrated device manufacturer (IDM) is a semiconductor company which designs, manufactures, and sells integrated circuit (IC) products.\nIDM is often used to refer to a company which handles semiconductor manufacturing in-house, compared to a fabless semiconductor company, which outsources production to a third-party semiconductor fabrication plant.\nExamples of IDMs are Intel, Samsung, and Texas Instruments, examples of fabless companies are AMD, Nvidia, and Qualcomm, and examples of pure play foundries are GlobalFoundries, TSMC, and UMC.\nDue to the dynamic nature of the semiconductor industry, the term IDM has become less accurate than when it was coined.\nOSATs.\nThe term OSATs means \"outsourced semiconductor assembly and test providers\". OSATs have dominated IC packaging and testing.\nFabless operations.\nThe terms fabless (fabrication-less), foundry, and IDM are now used to describe the role a company has in a business relationship. For example, Freescale owns and operates fabrication facilities (fab) where it manufactures many chip product lines, as a traditional IDM would. Yet it is known to contract with merchant foundries for other products, as would fabless companies.\nManufacturers.\nMany electronic manufacturing companies engage in business that would qualify them as an IDM:", "Engineering,_Manufacturing": 1.0000052452, "qwen": "Yes"}
{"id": "60574037", "revid": "33011235", "url": "https://en.wikipedia.org/wiki?curid=60574037", "title": "Aligner (semiconductor)", "text": "An aligner, or mask aligner, is a system that produces integrated circuits (IC) using the photolithography process. It holds the photomask over the silicon wafer while a bright light is shone through the mask and onto the photoresist. The \"alignment\" refers to the ability to place the mask over precisely the same location repeatedly as the chip goes through multiple rounds of lithography. Aligners were a major part of IC manufacture from the 1960s into the late 1970s, when they began to be replaced by the stepper.\nThere are several distinct generations of aligner technology. The early contact aligners placed the mask in direct contact with the top surface of the wafer, which often damaged the pattern when the mask was lifted off again. Used only briefly, proximity aligners held the mask slightly above the surface to avoid this problem, but were difficult to work with and required considerable manual adjustment. Finally, the Micralign projection aligner, introduced by Perkin-Elmer in 1973, held the mask entirely separate from the chip and made the adjustment of the image much simpler. Through these stages of development, yields improved from perhaps 10% to about 70%, leading to a corresponding reduction in chip prices.\nThe stepper is similar to an aligner in concept, but with one key difference. The aligner uses a mask that holds the pattern for the entire wafer, which may require large masks. The stepper uses a mask on the wafer repeatedly, and steps across the surface to repeat the pattern of the chip layer. This reduces mask costs dramatically and allows a single wafer to be used for different mask designs in a single run. More importantly, by focussing the light source onto a single area of the wafer, the stepper can produce much higher resolutions, thus allowing for smaller features on chips (minimum feature size). The disadvantage to the stepper is that each chip on the wafer has to be individually imaged, and thus the process of exposing the wafer as a whole is much slower.", "Engineering,_Manufacturing": 0.9984358549, "qwen": "Yes"}
{"id": "60600619", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=60600619", "title": "Reflective transformative design", "text": "The reflective transformative design process (RTDP) is a design method developed at Eindhoven University of technology department of Industrial design and proposes a more dynamic, and open design process compared to the more classical double diamond design process. Where the focus is on transforming society through design by continuously reflecting on your vision and the impact that the design will have. The sequence of the design path is not fixed, the focus is on reflection on the process and the result after each activity. It has overlap with the Lean startup method, in a way that it describes a cyclic, continuous process. It also has overlap with Action research, where research is done by actively participating in the research, in the case of RTDP the designer's artifact is participating in the context.\nElements of Reflective transformative design.\nThe main element of RTDP is ideating integrating, realizing which contains methods like prototyping, wizzard of ozz, sketching\nThe process is defined as a path though these actions, where the designer reflects on whether the design process is leading towards the envisioned goal.", "Engineering,_Manufacturing": 0.9945532084, "qwen": "Yes"}
{"id": "20851848", "revid": "1937176", "url": "https://en.wikipedia.org/wiki?curid=20851848", "title": "Internal fan-cooled electric motor", "text": "An internal fan-cooled electric motor (colloquially, \"fan-cooled motor\") is a self cooling electric motor. Fan cooled motors feature an axial fan attached to the rotor of the motor (usually on the opposite end as the output shaft) that spins with the motor, providing increased airflow to the motor's internal and external parts which aids in cooling.\nUses.\nFan cooled motors have many common uses in motors that either produce a lot of heat or have poor airflow because they are always stationary or in an enclosed space and require a compact cooling system. They are common for industrial uses, household appliances such as blenders and mixers, power tools such as drills and rotary tools, and radio-controlled cars\nAdvantages.\nAttaching an internal fan to a motor is a fairly simple way to cool it. Since a fan cooled motor always provides airflow over itself regardless of whether it is stationary or partially enclosed, it is more effective than using a heat sink in applications with poor airflow because heat sinks usually require air to be flowing over them for maximum effectiveness. Internal fan cooling also takes up far less space than external fan cooling or water cooling.\nDisadvantages.\nAll fans generate noise, something that may not be desired in a motor, and drag on their power source. Also, like any device with a fan, increased airflow through the motor can cause increased dust build up, which could potentially hinder the motor's operation.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "20860905", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=20860905", "title": "Plane strain compression test", "text": "The plane strain compression test is a specialized test used on some materials ranging from metals to soils.\nMetals.\nOne variation of the test is also known as the \"Watts-Ford test\". It is an engineering test, and is a particularly specialized way of determining some of the material characteristics of the metal being tested, and its specialization can be summarized by this quote:\nThe test is useful when the sheet pieces are too small for a tensile test of a balanced biaxial test. It can give stress-strain curves up to considerably higher strains than tensile tests.\nPlane-strain compression testing is typically used for measuring mechanical properties and for exploring microstructure development in the course of thermomechanical treatment. During the test the specimen is placed between the punches and the constrain plates. When the upper punch is pushed down during the material test, the specimen is extended to horizontal directions. Friction between the tool and the specimen can be reduced by applying lubricants, such as graphite, MoS2, glass or PTFE(Teflon).\nThe testing essentially consists of a thin metal bar being compressed by two equally wide compressive strips, which are located of opposite sides of the thin bar. Then, over a range of increasing loads on the bar, the compressive forces lead to the thickness of the metal bar being reduced. This change of thickness is then measured sequentially after each loading, and after some mathematics a stress-strain curve can be plotted.\nThe advantages of the Watts-Ford test are that it is convenient for testing thin sheets or strips, it is similar to a rolling process (in manufacturing analyses), frictional effects may be minimized, there is no 'barrelling' as would occur in a cylindrical compression test, and the plane strain deformation eases the analysis.\nStress-strain curve\nThe stress-strain curve is the relationship between the stress (force per unit area) and strain (resulting compression/stretching, known as deformation) that a particular material displays; stress–strain curves of various materials differ widely, and different tensile tests conducted on the same material yield different results depending upon the temperature of the specimen and the speed of the loading. When performing Watts-Ford tests, temperatures of the metal specimens will vary from 800-1100 °C and strain rates of (0.01- 10 s-1).\nPressure\nThe average pressure on a unit of area of the contact surface between the punch and the specimen is expressed as: P= F/(wb), where F is force, w is the punch width, b is the specimen width.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "6168576", "revid": "2278355", "url": "https://en.wikipedia.org/wiki?curid=6168576", "title": "Shift time", "text": "Shift time refers to the time interval between gear changes in a transmission. This interval is the time in which power delivery is transferred to the next selected gear, and engine speed is reduced or increased to synchronize the speed of the next gear. Shift time is usually in reference to motor vehicles, but can apply to any gearbox.\nReducing shift time is important in performance and racing vehicles because upshifting generally interrupts power delivery to the wheels. Shift time in a manual gearbox is dependent on the driver, but in automatic or automated manual cars, the electronic or hydraulic control system must be calibrated and tuned to execute fast gear changes. Generally, a dual-clutch transmission shifts faster than a standard hydraulic automatic transmission with a torque converter or a single-clutch automated manual transmission. This is possible because the DCT can pre-select the next gear and switch between its two separate clutches to the next pre-determined gear, thus reducing shift times. Using a freewheel may reduce shift time, as it may not be necessary to use the clutch. A shift kit is also intended to reduce the shift time of a manual vehicle.\nWith a manual transmission, upshift time can be reduced by installing a lighter flywheel. During an upshift, the engine speed must decrease to synchronize with a higher gear; a lighter flywheel will allow the engine speed to drop more quickly, leading to shorter shift times.\nShift times.\nExample upshift times.\nPlease note that manufacturers may have different definitions of shift times.", "Engineering,_Manufacturing": 0.9999579191, "qwen": "Yes"}
{"id": "44664089", "revid": "44756412", "url": "https://en.wikipedia.org/wiki?curid=44664089", "title": "Hermle AG", "text": "Maschinenfabrik Berthold Hermle AG is a publicly traded German company with headquarters in Gosheim, Baden-Württemberg, Germany. It is one of the leading manufacturers of milling machines. There are over 20,000 Hermle-manufactured machines in use worldwide. The chief users are suppliers of medical technology, the optical industry, aviation, and the automotive industry and racing.\nMost development and manufacturing is located in Gosheim. The universal milling machines and machining centers from Hermle are used to produce tools, molds, and production parts.\nHistory.\nIn 1938 Berthold Hermle founded \"Berthold Hermle Gosheim - Schraubenfabrik and Fassondreherei\". In 1957 the company began production of milling machines. Hermle went public in 1990 and changed its name to \"Maschinenfabrik Berthold Hermle AG\"—previously, it was primarily known by its initials of BHG (for Berthold Hermle Gosheim).", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "224022", "revid": "29863264", "url": "https://en.wikipedia.org/wiki?curid=224022", "title": "Solder ring fitting", "text": "A solder ring fitting, also known by the trademarked name Yorkshire fitting, is a pre-soldered capillary connector for joining copper pipes used in plumbing.\nOperation.\nTo obtain perfect joins, the inside of the fitting and the outside of the copper pipe are cleaned using coarse steel wool, flux paste is applied, the pipe is inserted into the fitting and heat applied from a portable propane torch until a ring of solder shows at the edges of the fitting. To obtain a durable joint, water must not be poured on the solder joint to cool it. Yorkshire fittings are now made with lead-free solder.\nThe fittings come in a great variety of configurations, such as Tee-pieces, straight couplers, elbows or bends, reducers (to join pipes of different diameters), stop-ends, and there are versions with screw threads (male or female) at one end to fit taps and galvanized iron pipes.\nValves such as stoptaps & gate valves are also available in solder ring configuration.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "3091206", "revid": "33011235", "url": "https://en.wikipedia.org/wiki?curid=3091206", "title": "Die head", "text": "A die head is a threading die that is used in the high volume production of threaded fasteners.\nDie heads are commonly used on lathes, turret lathes, screw machines and CNC lathes. They may be used for either cutting a thread or rolling a thread. They may also be used for internal or external thread cutting.\nIn operation, there are usually four moveable chasers that cut the thread then back away from the work to permit rapid removal of the tool. The lower picture at the right shows four sets of chasers. Each set of chasers is designed to cut a different thread. One set of chasers would be used at a time, each chaser is inserted into the die head (in the correct order) and the die head is closed bringing the chasers down to their cutting position. When sufficient length of thread has been cut the die head will open allowing for rapid retraction of the head without interference with the newly formed thread.\nThe die head shown cuts an outside thread. There are also collapsible die heads that are used to cut an internal thread.\nThe bottom picture shows a Die Head used for Thread Rolling. A Rolled Thread may have greater strength than a cut thread, though it usually requires more energy to roll a thread than cut one.", "Engineering,_Manufacturing": 0.9999747276, "qwen": "Yes"}
{"id": "3238462", "revid": "3306290", "url": "https://en.wikipedia.org/wiki?curid=3238462", "title": "Renishaw plc", "text": "Renishaw plc is a British engineering company based in Wotton-under-Edge, England. The company's products include coordinate-measuring machines and machine tool products. It is listed on the London Stock Exchange and is a constituent of the FTSE 250 Index.\nHistory.\nThe company was founded by Sir David McMurtry and John Deer in 1973. McMurtry had needed to measure fuel pipes on a prototype jet engine: at the time, coordinate-measuring machine sensors featured rigid styli, which required manual positioning on the surface and which yielded poor repeatability when measuring delicate components. To meet this need, McMurtry invented a touch-trigger probe device, which he then patented. The probe featured an elegant 'kinematic' location for a spring-loaded stylus, providing a highly repeatable seated position for the stylus combined with the compliance needed to measure such components.\nRenishaw was first listed on the London Stock Exchange in November 1984. In 2006 the Company bought 'itp', a German manufacturer of precision styli. In early 2009 the global recession reached Renishaw, resulting in a large proportion of the workforce being placed \"at risk\".\nIn 2010 Renishaw bought a stake (and subsequently took complete control) of Measuring Devices Ltd, a company providing a range of services in the field of surveying equipment. In 2011 Renishaw purchased the 400,000 sq ft Bosch plant in Miskin, Wales.\nOperations.\nThe company's product portfolio includes touch probes for CNC machine tools, calibration systems that optimise the performance of CNC machinery, linear encoder systems, rotary encoder systems, additive manufacturing machines, dental CAD/CAM systems, Raman spectroscopy and medical devices for functional neurosurgery applications.\nLocations.\nRenishaw's main offices are situated in Gloucestershire in an old watermill, with several new buildings on a site. The company has a machine shop located at Stonehouse, Gloucestershire, and an assembly facility at Woodchester, both near Stroud. There are further assembly facilities in Dublin (Ireland) and Pune (India). Renishaw also has research facilities located in Wotton-under-Edge, Edinburgh and Ljubljana.\nSale of Renishaw.\nOn 2 March 2021, David McMurtry and John Deer indicated that they wished to dispose of their entire holdings in Renishaw, comprising some 53% of the shares, as 'we recognise that neither of us is getting any younger'. The Renishaw board then announced that it was launching a formal sale process for the entire company. This process was terminated on 7 July 2021, the board concluding that none of the proposals met their objectives.", "Engineering,_Manufacturing": 0.9996809959, "qwen": "Yes"}
{"id": "34010616", "revid": "34738792", "url": "https://en.wikipedia.org/wiki?curid=34010616", "title": "Transient liquid phase diffusion bonding", "text": "Transient liquid phase diffusion bonding (TLPDB) is a joining process that has been applied for bonding many metallic and ceramic systems which cannot be bonded by conventional fusion welding techniques. The bonding process produces joints with a uniform composition profile, tolerant of surface oxides and geometrical defects. The bonding technique has been exploited in a wide range of applications, from the production and repair of turbine engines in the aerospace industry, to nuclear power plants, and in making connections to integrated circuit dies as a part of the microelectronics industry.\nProcess.\nThe process differs from diffusion bonding, in which diffusion occurs when a melting point represent element from an interlayer moves into lattice and grain boundaries of the substrates at the bonding temperature. Solid state diffusional processes lead to a change of composition at the bond interface and the dissimilar interlayer melts at a lower temperature than the parent materials. Thus a thin layer of liquid spreads along the interface to form a joint at a lower temperature than the melting point of either of the parent materials. This method differs from brazing in that it is \"isothermally solidifying\". While holding the temperature above the filler metal melting point, interdiffusion shifts the composition away from eutectic, so solidification occurs at the process temperature. If sufficient interdiffusion occurs, the joint will remain solid and strong well above the original melt process temperature. This is why it is termed \"transient liquid phase.\" The liquid solidifies before cooling.\nInterlayer.\nIn this technique it is necessary to select a suitable interlayer by considering its wettability, flow characteristics, high stability to prevent reactions with the base materials, and the ability to form a composition having a remelt temperature higher than the bonding temperature. The joining technique dates back to ancient times. \n For example, copper oxide painted as an interlayer and covered with tallow or glue to hold gold balls on to a gold article were heated in a reducing flame to form a eutectic alloy alloy at the bond area.\nKinetics.\nThere are many theories on the kinetics of the bonding process but the most common theory divides the process into four main stages. \n The stages are:", "Engineering,_Manufacturing": 0.9999997616, "qwen": "Yes"}
{"id": "7494752", "revid": "20295151", "url": "https://en.wikipedia.org/wiki?curid=7494752", "title": "Blisk", "text": "A blisk (portmanteau of bladed disk) is a turbomachine component comprising both rotor disk and blades. It serves as a critical component of the engine compressor to allow a sufficient quantity of compressed air to enter the engine for combustion to occur. Blisks generally have better aerodynamics than conventional rotors with single blades and are lighter. Each blisk consists of a single part instead of a disk assembled with individual removable blades. They may be additively manufactured, integrally cast, machined from a solid piece of material, or made by welding individual blades to a rotor disk. The term is used mainly in aerospace engine design. \"Blisks\" may also be known as integrally bladed rotors (IBR).\nHistory.\nBlisk manufacturing has been used since the mid-1980s. It was first used by Sermatech-Lehr (now known as GKN Aerospace) in 1985 for the compressors of the T700 helicopter engine. Since then, its use has continued to increase in major applications for both compressors and fan blade rotors. Examples include the Rocketdyne RS-68 rocket engine and the General Electric F110 turbofan.\nThe F-35B variant of the Joint Strike Fighter uses blisks to achieve short take-off and vertical landing.\nEngine manufacturer CFM International is using blisk technology in the compressor section of its Leap-X demonstrator engine program, which has completed full-scale rig testing. PowerJet SaM146 engines used on Sukhoi Superjet 100s are also equipped with blisks.\nGeneral Electric's Passport (formerly \"TechX\") engine uses blisks for both its main 52\" fan as well as for 5 of its 10 high pressure turbine stages. The GEnx already uses blisks in some stages.\nAdvantages.\nInstead of making bare compressor disks and attaching the blades later, blisks are single elements combining the two. This eliminates the need to attach the blades to the disk (via screws, bolts, etc.), thus decreasing the number of components in the compressor, while at the same time decreasing drag and increasing efficiency of air compression in the engine. The elimination of the dovetail attachment found on traditional turbine blades eliminates a source for crack initiation and subsequent propagation.\nEfficiency improvements of up to 8% are possible.\nDisadvantages.\nAny damage to integrally bladed rotor blades beyond minor dents requires the full removal of the engine so that the rotor may be replaced or, if possible, replacement blades welded on. Maintenance of this nature cannot be done on the flightline and often must be performed at a specialized facility. Integrally bladed rotor blades must undergo rigorous harmonic vibration testing as well as dynamic balancing to an extremely high standard, since the natural damping of the dovetail attachment of a typical turbine blade is no longer present.\nProcess.\nGeneral.\nBlisks can be produced with several different manufacturing processes, including CNC milling, investment casting, electro chemical machining, 3D printing, or welding. Research is being conducted to produce them using friction welding of \"near net\" part shapes that are then machined down to the final blisk shape.\nMeasurement and inspection.\nThe measurement and inspection of blisks is crucial for guaranteeing engine performance carried out at the end of the manufacturing processes. Traditionally this has been achieved using tactile devices, like CMMs, but as geometries and requirements increase, the trend in modern factories is to carry out 3D scanning using systems like ATOS ScanBox. This has advantages of the speed of measurement compared to tactile devices, whilst collecting 3D data to relate back to design characteristics. Using 3D data, parts can be catalogued in this way, often called digital twin, allowing monitoring of the product through its life-cycle.\nBlisk repair using adaptive machining.\nEngine-run blisks pose their own set of unique requirements. After parts have been in service in the engine, noticeable amounts of damage and wear will be observed. Provided that the damage and wear are within thresholds set by the design authority, it is possible that the blisks can repaired.\nRepair of blisk components is complex and first requires an accurate 3D representation of the component. The quickest way to do this is by 3D scanning the product. After the part is scanned, an STL file can be passed to a CNC code generating software such as NX CAM. The tool paths are regenerated to suit the measured geometry and not the nominally generated CAD in a process known as adaptive machining.\nThe processes would typically involve removing part or all of a blade(s), followed by a weld back to approximate size before finishing by final machining back to the airfoil shape.", "Engineering,_Manufacturing": 1.0000016689, "qwen": "Yes"}
{"id": "387961", "revid": "45891502", "url": "https://en.wikipedia.org/wiki?curid=387961", "title": "Cutting", "text": "Cutting is the separation or opening of a physical object, into two or more portions, through the application of an acutely directed force.\nImplements commonly used for cutting are the knife and saw, or in medicine and science the scalpel and microtome. However, any sufficiently sharp object is capable of cutting if it has a hardness sufficiently larger than the object being cut, and if it is applied with sufficient force. Even liquids can be used to cut things when applied with sufficient force (see water jet cutter).\nCutting is a compressive and shearing phenomenon, and occurs only when the total stress generated by the cutting implement exceeds the ultimate strength of the material of the object being cut. The simplest applicable equation is:\nformula_1 or formula_2\nThe stress generated by a cutting implement is directly proportional to the force with which it is applied, and inversely proportional to the area of contact. Hence, the smaller the area (i.e., the sharper the cutting implement), the less force is needed to cut something. It is generally seen that cutting edges are thinner for cutting soft materials and thicker for harder materials. This progression is seen from kitchen knife, to cleaver, to axe, and is a balance between the easy cutting action of a thin blade vs strength and edge durability of a thicker blade.\nMetal cutting.\nCutting has been at the core of manufacturing throughout history. For metals many methods are used and can be grouped by the physical phenomenon used. It is the process of producing a work piece by removing unwanted material from a block of metal, in the form of chips.\nEvery method has its limitations in accuracy, cost, and effect on the material. For example, heat may damage the quality of heat treated alloys, and laser cutting is less suitable for highly reflective materials such as aluminum. Laser cutting sheet metal produces flat parts and etches and engraves parts from complex or simple designs. It is used over other cutting options for its quick process and customizable abilities.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "7915944", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=7915944", "title": "Engineer to order", "text": "Engineer to order is a production approach characterized by:\nTo speed up delivery time, the adoption of concurrent engineering, integrated product team, and lean product development methodologies are used. The critical path methodology is also essential. To speed up the delivery time, many companies use customization approach (In SAP terminology it is called Variant configuration) where in, the most part of the BOM components and routing operation elements could be created automatically based on the design inputs received during quote/sales order stage. This approach speedup the BOM and routing creation process, there by help ETO companies to respond quickly to customer requirement.\nEngineer to order environments must employ a flexible and adaptive, demand-driven approach to the manufacturing process. It is usually the right solution when details on a customer order are not provided and engineering development must be added to product lead time.\nETO is a technique that is leveraged to boost sales and improve margins for those companies with customers needing solutions that are tailored to fit their own unique environment. It begins with selling product concepts that don’t have fixed designs and are expected to result in a new, unique end product. This could be any product, from enterprise software applications to special aircraft to a pair of jeans. But the typical ETO environment usually deals with the design and build of unique custom engineered complex machinery and industrial equipment - one in which there is heavy involvement of the following engineering disciplines; mechanical, electrical, mechatronics, software, manufacturing and systems engineering. The ETO company works with its customers to develop new products that satisfy the customer’s requirements and specifications.\nEngineer to order vs Make to Order.\nThe difference between the ETO approach to production and make to order products is that engineering original products to order includes the entire design process. In MTO companies typically have a fixed design and specifications to start with. The existing design is followed, even if the customer requests some customization of dimensions or materials. In engineering to meet unique customer orders, designs spring from collaboration with the customer, beginning with a need and a concept. Engineers do not know the final specifications, materials, or in software development, even the network or application platform until other primary concepts are ironed out. This is a much more creative process and requires a much closer relationship with clients, ultimately leading to a product that is unique.\nProcess Flow.\nEngineers don’t always follow a smooth flow from step to step even in ordinary manufacturing. Most manufacturing design decisions tends to be highly iterative. It is common to create a design that meets customer approval, test it, make changes to meet specifications, and resubmit at certain stages or milestones in order for approval to proceed to the next stage. Engineer to order, due to its nature, is even more complex and client-centric. This requires on-going documentation, but the approach typically involves all of the following steps.\nQuality.\nGiven the unique nature of the delivered product, clients may accept certain quality risks as a consequence of meeting delivery dates. Testing and trial periods may also be limited by the nature of the product, the manufacturing required, and the metrics established for quality controls. As each product is essentially a one of a kind prototype, smaller companies on either the manufacturer or client side may not have the expertise or resources to implement use-cases, user testing, or future quality guidelines. In MTO, quality is often defined as a lack of defects, but must meet minimal levels defined in the specifications. In Engineer to Order there is no original design. Where possible, prior similar products may provide some guidelines as to testing and precision, but the idea of re-designing or modifying an existing design is necessarily a core requirement of the engineer to order concept. It does however reduce costs and time if one can use previous designs.", "Engineering,_Manufacturing": 1.0000052452, "qwen": "Yes"}
{"id": "7920832", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=7920832", "title": "Food packaging", "text": "Food packaging is a packaging system specifically designed for food and represents one of the most important aspects among the processes involved in the food industry, as it provides protection from chemical, biological and physical alterations. The main goal of food packaging is to provide a practical means of protecting and delivering food goods at a reasonable cost while meeting the needs and expectations of both consumers and industries. Additionally, current trends like sustainability, environmental impact reduction, and shelf-life extension have gradually become among the most important aspects in designing a packaging system.\nHistory.\nPackaging of food products has seen a vast transformation in technology usage and application from the stone age to the industrial revolution:\n7000 BC: The adoption of pottery and glass which saw industrialization around 1500 BC. \n1700s: The first manufacturing production of tinplate was introduced in England (1699) and in France (1720). Afterwards, the Dutch navy start to use such packaging to prolong the preservation of food products.\n1804: Nicolas Appert, in response to inquiries into extending the shelf life of food for the French Army, employed glass bottles along with thermal food treatment. Glass has been replaced by metal cans in this application. However, there is still an ongoing debate about who first introduced the use of tinplates as food packaging.\n1870: The use of paper board was launched and corrugated materials patented.\n1880s: First cereal packaged in a folding box by Quaker Oats.\n1890s: The crown cap for glass bottles was patented by William Painter. \n1960s: Development of the two-piece drawn and wall-ironed metal cans in the US, along with the ring-pull opener and the Tetra Brik Aseptic carton package.\n1970s: The barcode system was introduced in the retail and manufacturing industry. PET plastic blow-mold bottle technology, which is widely used in the beverage industry, was introduced.\n1990s: The application of digital printing on food packages became widely adopted.\nPlastic packaging saw its inaugural use during World War II, even though materials employed in its manufacturing (such as cellulose nitrate, styrene and vinyl chloride) were discovered in the 1800s.\nFunctions.\nPackaging and package's labeling have several objectives:\nTypes.\nPackaging design may vary largely depending on the function that are fashioned into different types of packages and containers, and depending on the food products and their function, such as:\nSince almost all food products is packed in some fashion, food packaging is both fundamental and pervasive. Additionally, by enabling the creation and standardization of brands, it provides the opportunity to realized significant advertising, extensive distribution, and mass merchandising. Therefore, a distinction between the various type (or level) of packaging needs to be made. \nPrimary packaging.\nPrimary packaging is directly in contact with the food products, creating the ideal headspace for them while providing protection from external alteration. Additionally, primary packaging, also known as retail packaging or consumer units, is responsible for the marketing aspects of food packaging. Typically, the packaging materials used in the primary level include cardboard cartons, plastic trays, glass bottle and multi-layerd structure (Tetra Pak).\nSecondary packaging.\nSecondary packaging contains a number of primary packages into one box being made usually out of corrugated cardboard. Thus, the secondary level is a physical distribution carrier for the primary packages, making more easy to handle during the transportation. Occasionally it can be used as an aid in retail outlets or super market for the display of basic goods.\nTertiary packaging.\nThe outermost package, known as tertiary packaging, makes it easier to handle, store, and distribute both primary and secondary packages in bulk safely, providing further protection of the product while creating an easy way to transport large quantities of materials. The most familiar type of tertiary packaging comprises a wrapped pallet of corrugated case.\nPackaging machines.\nA choice of packaging machinery requires consideration of technical capabilities, labor requirements, worker safety, maintainability, serviceability, reliability, ability to integrate into the packaging line, capital cost, floorspace, flexibility (change-over, materials, etc.), energy usage, quality of outgoing packages, qualifications (for food, pharmaceuticals, etc.), throughput, efficiency, productivity, and ergonomics, at a minimum.\nPackaging machines may be of the following general types:\nReduction of food packaging.\nReduced packaging and sustainable packaging are becoming more frequent. The motivations can be government regulations, consumer pressure, retailer pressure, and cost control. Reduced packaging often saves packaging costs.\nIn the UK, a Local Government Association survey produced by the British Market Research Bureau compared a range of outlets to buy 29 common food items, and found that small local retailers and market traders \"produced less packaging and more that could be recycled than the larger supermarkets.\"\nIn the last decades, the growing demand from the consumers and governments for more sustainable and eco-friendly packaging design has driven the food industry to re-design and propose alternative packaging solutions. However, in designing a brand new packaging system, several variables need to be taken in consideration. An ideal packaging design should only use the right amount of the appropriate materials to provide the desired performance for a specific product. As shown in the optimum packaging design chart, the variety of situations in which product losses occur increases as the material weight or volume is decreased.\nSuch trend will eventually reach a situation in which the loss outweighs the cost savings from using less packing material. Beyond that point, any packing reduction increases the overall quantity of waste in the system, rendering it a false benefit. The goal of the optimal packaging design is to identify a weight below which the package can no longer be sold since it does not satisfy the specifications, while considering the environmental impact connected to the materials selection.\nRecycling of food packaging.\nFood packaging is created through the use of a wide variety of plastics and metals, papers, and glass materials. Recycling these products differs from the act of literally reusing them because the recycling process has its own algorithm which includes collecting, sourcing, processing, manufacturing and marketing these products. According to the Environmental Protection Agency of the United States, the recycling rate has been steadily on the rise, with data reporting that in 2005 40% of the food packaging and containers that were created were recycled.\n\nThe product's quality and safety are the package's most important responsibility. However, there have been growing demands for packaging to be designed, manufactured, consumed, and recycled in a more sustainable fashion due to the increasing pollution connected with packaging and food wastes. It has been estimated that only 10.33% of all municipal solid waste (MSW), which makes up to 30.3% of the total waste, is recycled into new products globally.\nHowever, depending on the level of packaging and the materials that are being used during their manufacturing, the end-of-life of a package may differ completely. Despite the fact that a recycling process is usually the desired path, lots of complications may lead to less sustainable destines.\nFood packaging barriers.\nA critical requirement in food packaging is represented by the barrier properties against the permeation of gases, water vapor, and aroma compounds of the packaging system. In fact, the chemical interactions between the products and the environment are the principal reasons for improper shelf-life and spoilage phenomena. Therefore, the evaluation of the gas exchange by means of the permeation of gas molecules is a crucial aspect in designing a product.\nThe permeation of a gas molecule through a packaging system is a physical process made up of three independent phenomena: the adsorption of the molecule to the packaging's outer surface; the diffusion of the molecule through the packaging’s section; and the desorption in the internal headspace. Under the assumption of steady state condition, the physical processes involved in the permeation can be modeled by simple equations. Particularly, the diffusion of a permeant's molecule is dependent to the concentration difference between the two sides of the packaging system, which acts as a driving force, thus creating a diffusive flux following the first Fick's law of diffusion. \nFurthermore, other assumptions are needed, such as the absence of chemical interaction between the penetrant and the packaging material and the fact that the diffusion flow must follow only one direction. The adsorption/desorption processes of a permeant's molecule normally exhibit a linear dependency with the partial pressure gradient across the barrier layer while keeping the assumption of steady-state transport condition and exhibiting a concentration lower than the penetrant's maximum solubility, thereby adhering to Henry's law of solubility.\nThe type of permeant, the barrier layer's thickness, the specific permeabilities of the packaging films against gases or vapors, the packaging's permeable area, the temperature, and the pressure or concentration gradient between the barrier's interior and external sides can all have an impact on a system's permeability.\nThe gas exchange occurring between the packaging system and the external environment has a significant impact on the quality and safety of food products. Uncontrolled physico-chemical and biological processes such as oxidation of vitamins, excessive microbial growth, and spoilage of the packed food may lead to improper conditions inside the packaging headspace, hence reducing their shelf-life. Therefore, the packaging system should be designed to create the ideal conditions for the selected product, avoiding excessive gas exchange.\nAmong the permeants that could affect the organoleptic properties of food, oxygen and water vapor represent the most important ones. These permeants affect several bio-chemical processes in food products, such as ripening, degradation, hydration/dehydration, microbial growth, vitamins oxidation; they also have an impact on the organoleptic properties, hence causing off-flavours, excessive weight loss, textural changing and generally shortening the shelf life.\nTo quantify the barrier properties of a packaging system, both oxygen and water vapor permeation are commonly assessed by measuring the oxygen transmission rate (OTR) and water vapor transmission rate (WVTR), respectively.\nOxygen barrier.\nThe oxygen transmission rate of a gas through the packaging is defined as the amount of oxygen permeating per unit of permeable area and unit of time in a packaging system considering standardized test conditions (23 °C and 1 atm partial pressure difference). It is an effective tool to estimate the barrier properties of a certain material. The determination of the OTR is usually carried out by means of a steady-state and isostatic method, reported by the ASTM D 3985 or ASTM F 1307, containing respectively standardized protocol for the measurements of the OTR of several kind of packaging. \nThe typical instrumentation consists in a permeation cell composed by two distinct chambers separated by the tested material; one of the chambers is then filled with a carrier gas (e.g., nitrogen), while the other one with oxygen, hence creating the necessary driving force to let the oxygen permeate across the barrier’s material.\nWater vapor barrier.\nConcurrently to the oxygen barrier property, the permeability of water vapor through a food packaging system should be minimized to effectively prevent physical and chemical changes connected to an excessive moisture content.The moisture barrier properties of a material can be assessed by measuring the water vapor transmission rate (WVTR), which can be defined as the amount of water vapor per unit of area and unit of time passing through the packaging film. \nThe WVTR measurements, like the OTR, adhere to the standards for standardized tests as outlined in the ASTM E96 (standard methods for water vapor transmission of materials). An impermeable test dish (such as a stainless steel cup) and a test chamber where temperature and relative humidity (RH) can be adjusted in accordance with the standard specification, make up the basic instrumentation used in such tests.\nOther vapors.\nAlthough both oxygen and water vapor represent the most studied permeants in food packaging application, other gases such as carbon dioxide (CO2) and nitrogen (N2) have also great relevance in the preservation of food products. In fact, N2 and CO2 have been employed in modified atmosphere packaging (MAP) technology to establish the correct conditions inside the package's headspace to lessen food spoiling.\nFood safety and public health.\nIt is critical to maintain food safety during processing, packaging, storage, logistics (including cold chain), sale, and use. Conformance to applicable regulations is mandatory. Some are country specific such as the US Food and Drug Administration and the US Department of Agriculture; others are regional such as the European Food Safety Authority. Certification programs such as the Global Food Safety Initiative are sometimes used. Food packaging considerations may include: use of hazard analysis and critical control points, verification and validation protocols, Good manufacturing practices, use of an effective quality management system, track and trace systems, and requirements for label content. Special food contact materials are used when the package is in direct contact with the food product. Depending on the packaging operation and the food, packaging machinery often needs specified daily wash-down and cleaning procedures.\nHealth risks of materials and chemicals that are used in food packaging need to be carefully controlled. Carcinogens, toxic chemicals, mutagens etc. need to be eliminated from food contact and potential migration into foods. Besides, the consumers need to be aware of certain chemical products that are packaged exactly like food products to attract them. Most of them have pictures of fruits and the containers also resemble food packages. However, they can get consumed by kids or careless adults and lead to poisoning.\nManufacturing.\nPackaging lines can have a variety of equipment types: integration of automated systems can be a challenge. All aspects of food production, including packaging, are tightly controlled and have regulatory requirements. Uniformity, cleanliness and other requirements are needed to maintain Good Manufacturing Practices.\nProduct safety management is vital. A complete Quality Management System must be in place. Hazard analysis and critical control points is one methodology which has been proven useful. Verification and validation involves collecting documentary evidence of all aspects of compliance. Quality assurance extends beyond the packaging operations through distribution and cold chain management.", "Engineering,_Manufacturing": 0.999887228, "qwen": "Yes"}
{"id": "1658718", "revid": "30433211", "url": "https://en.wikipedia.org/wiki?curid=1658718", "title": "Grinding wheel", "text": "Grinding wheels are wheels that contain abrasive compounds for grinding and abrasive machining operations. Such wheels are also used in grinding machines.\nThe wheels are generally made with composite material. This consists of coarse-particle aggregate pressed and bonded together by a cementing matrix (called the \"bond\" in grinding wheel terminology) to form a solid, circular shape. Various profiles and cross sections are available depending on the intended usage for the wheel. They may also be made from a solid steel or aluminium disc with particles bonded to the surface. Today most grinding wheels are artificial composites made with artificial aggregates, but the history of grinding wheels began with natural composite stones, such as those used for millstones.\nThe manufacture of these wheels is a precise and tightly controlled process, due not only to the inherent safety risks of a spinning disc, but also the composition and uniformity required to prevent that disc from exploding due to the high stresses produced on rotation.\nGrinding wheels are consumables, although the life span can vary widely depending on the use case, from less than a day to many years. As the wheel cuts, it periodically releases individual grains of abrasive, typically because they grow dull and the increased drag pulls them out of the bond. Fresh grains are exposed in this wear process, which begin the next cycle. The rate of wear in this process is usually very predictable for a given application, and is necessary for good performance.\nCharacteristics.\nThere are five characteristics of a cutting wheel: abrasive material, grain size, wheel grade, grain spacing, and bond type. They are indicated by codes on the wheel's label.\nAbrasive Material.\nThe abrasive aggregate is selected primarily according to the hardness of the material being cut. Chemical compatibility is also a concern. For example because carbon alloys with iron, silicon carbide is not suitable for use with iron-based metals like steel.\nGrinding wheels with diamond or CBN grains are called superabrasives. Grinding wheels with aluminum oxide (corundum), silicon carbide, or ceramic grains are called conventional abrasives.\nGrain size.\nFrom 10 (coarsest) to 600 (finest), determines the average physical size of the abrasive grains in the wheel. A larger grain will cut freely, allowing fast cutting but poor surface finish. Ultra-fine grain sizes are for precision finish work.\nGenerally, grain size of grinding wheels are 10-24 (coarse), 30-60 (medium), 80-200 (fine), and 220-600 (very fine).\nWheel grade.\nFrom A (soft) to Z (hard), determines how tightly the bond holds the abrasive. \nA to H for softer structure,\nI to P for moderately hard structure and\nQ to Z for hard structure. Grade affects almost all considerations of grinding, such as wheel speed, coolant flow, maximum and minimum feed rates, and grinding depth.\nGrain spacing.\nSpacing or structure, from 1 (densest) to 17 (least dense). Density is the ratio of bond and abrasive to air space. A less-dense wheel will cut freely, and has a large effect on surface finish. It is also able to take a deeper or wider cut with less coolant, as the chip clearance on the wheel is greater.\nWheel bond.\nHow the wheel holds the abrasives; affects finish, coolant, and minimum/maximum wheel speed.\nTypes.\nStraight wheel.\nTo the right is an image of a straight wheel. These are by far the most common style of wheel and can be found on bench or pedestal grinders. They are used on the periphery only and therefore produce a slightly concave surface (\"hollow ground\") on the part. This can be used to advantage on many tools such as chisels.\nStraight Wheels are generally used for cylindrical, centreless, and surface grinding operations. Wheels of this form vary greatly in size, the diameter and width of face naturally depending upon the class of work for which is used and the size and power of the grinding machine.\nCylinder or wheel ring.\nCylinder wheels provide a large, wide surface with no center mounting support (hollow). They can be very large, up to 12\" in width. They are used only in vertical or horizontal spindle grinders.\nCylinder or wheel ring is used for producing flat surfaces, the grinding being done with the end face of the wheel.\nTapered wheel.\nA straight wheel that tapers outward towards the center of the wheel. This arrangement is stronger than straight wheels and can accept higher lateral loads.\nTapered face straight wheel is primarily used for grinding thread, gear teeth ...\nStraight cup.\nStraight cup wheels are an alternative to cup wheels in tool and cutter grinders, where having an additional radial grinding surface is beneficial.\nDish cup.\nA very shallow cup-style grinding wheel. The thinness allows grinding in slots and crevices. It is used primarily in cutter grinding and jig grinding.\nSaucer wheel.\nA special grinding profile that is used to grind milling cutters and twist drills. It is most common in non-machining areas, as sawfilers use saucer wheels in the maintenance of saw blades.\nDiamond wheels.\n\"Diamond wheels\" are grinding wheels with industrial diamonds bonded to the periphery.\nThey are used for grinding extremely hard materials such as carbide cutting tips, gemstones or concrete. The saw pictured to the right is a slitting saw and is designed for slicing hard materials, typically gemstones.\nMounted points.\n\"Mounted points\" are small grinding wheels bonded onto a mandrel. Diamond mounted points are tiny diamond rasps for use in a jig grinder doing profiling work in hard material. Resin and vitrified bonded mounted points with conventional grains are used for deburring applications, especially in the foundry industry.\nMounted points is a small handle with a general name, used in electric mill, hanging mill, hand drill. Many of the main types of ceramic mounted points, rubber mounted points, diamond mounted points, emery cloth and so on.\nCeramic mounted points: granular sand (usually corundum, white jade, chrome corundum, silicon carbide) made of ceramic binder sintering, the central supplemented by metal handle. Mainly grinding all kinds of metal, for the diameter of the inner wall of the grinding, mold correction.\nRubber mounted points: finer particle size sand combined by rubber binder\nInto, for the polishing of the mold.\nsandpaper mounted points:\nMulti-piece rectangular sand cloth, bonding around the metal handle. Granularity is generally in the 60 # -320 #, for the diameter of the inner wall of the polishing.\nDiamond mounted points: A grinding tool for non-metallic materials such as stone, porcelain and the like, and more particularly to a grinding tool using a diamond alloy as a grinding body comprising a substrate and a plurality of grinding bodies, And the substrate is preferably made of an adhesive material having a certain toughness, and the grinding body is preferably made of a diamond alloy material, and the substrate is preferably made of a diamond alloy material, The utility model has the characteristics of high grinding performance, simple manufacture and low cost, high grinding quality and can be applied to large-scale grinding.\nCut off wheels.\n\"Cut off wheels\", also known as \"parting wheels\", are self-sharpening wheels that are thin in width and often have radial fibres reinforcing them. They are often used in the construction industry for cutting reinforcement bars (rebar), protruding bolts or anything that needs quick removal or trimming. Most handymen would recognise an angle grinder and the discs they use.\nUse.\nTo use the grinding wheel it must first be clamped to the grinding machine. The wheel type (\"e.g.\" cup or plain wheel below) fit freely on their supporting arbors, the necessary clamping force to transfer the rotary motion being applied to the wheels side by identically sized flanges (metal discs). The paper blotter shown in the images is intended to distribute this clamping force evenly across the wheels surface.\nDressing.\nGrinding wheels are self-sharpening to a small degree; for optimal use they may be dressed and trued by the use of wheel or grinding dressers. \"Dressing\" the wheel refers to removing the current layer of abrasive, so that a fresh and sharp surface is exposed to the work surface. \"Trueing\" the wheel makes the grinding surface parallel to the grinding table or other reference plane, so that the entire grinding wheel is even and produces an accurate surface.\nTesting for grinding tools.\nGrinding wheels and grinding tools are used extensively in industry and manual trades for treating surfaces and for separating and cutting objects and have to withstand massive mechanical stress. Mostly centrifugal forces can cause a break, but also flexural and shear forces. Since a break or failure of the grinding tool can present a severe hazard to people and machinery due to the high levels of energy released, high standards are placed on the mechanical and breaking strength of grinding tools in the European safety standards. The Institute for Occupational Safety and Health of the German Social Accident Insurance conducts tests based on the \"Rules of Procedure for Testing and Certification carried out by the Testing and Certification Bodies in DGUV Test\".", "Engineering,_Manufacturing": 0.9999022484, "qwen": "Yes"}
{"id": "1658855", "revid": "37102400", "url": "https://en.wikipedia.org/wiki?curid=1658855", "title": "Grinding dresser", "text": "A grinding dresser or wheel dresser is a tool to dress (slightly trim) the surface of a grinding wheel. Grinding dressers are used to return a wheel to its original round shape (to true it up), to expose fresh grains for renewed cutting action (including cleaning away clogged areas), or to make a different profile (cross-sectional shape) on the wheel's edge. Utilizing pre-determined dressing parameters will allow the wheel to be conditioned for optimum grinding performance while truing and restoring the form simultaneously. \nPurpose.\nThe objective of \"dressing the wheel\" is to:\nTypes.\nAlso an abrasive wheel type that has a small \"grinding wheel\" in a holder that is held against the spinning grinding wheel to dress and clean the face of the grinding wheel.\nGrinding complex shapes.\nFour types of dressers are used to dress the wheels of CNC grinders used for grinding complex shapes. This type of dresser is mainly in use on CNC grinding machine tools to automatically dress the grinding wheel via computer control in specialist areas requiring complex shapes such as grinding bearing raceways.\nWheel Conditioning\nProper wheel conditioning is a critical part of any grinding process. The condition of the wheel will determine the wheel's ability to meet the part finish requirements and metal removal rate capabilities. The grains in the wheel can be sheared to create a smooth condition or fractured to create a course open condition utilizing dressing parameters. \nSkate sharpening.\nGrinders used for sharpening skate blades typically have one or more thin grinding wheels mounted on vertical spindles, with a single-diamond dresser mounted on a gymbal with a horizontal axis level with the centerline of the wheel, so it can swing above and below the plane of the wheel, producing a convex grinding surface of a predetermined radius. This allows the blade to be sharpened to a specified hollow, typically very deep for hockey skates, very shallow for skates used for school figures, and moderate for skates used for freestyle skating.", "Engineering,_Manufacturing": 0.9996894598, "qwen": "Yes"}
{"id": "24355140", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=24355140", "title": "Multiaxis machining", "text": "Multiaxis machining is a manufacturing process that involves tools that move in 4 or more directions and are used to manufacture parts out of metal or other materials by milling away excess material, by water jet cutting or by laser cutting. This type of machining was originally performed mechanically on large complex machines. These machines operated on 4, 5, 6, and even 12 axes which were controlled individually via levers that rested on cam plates. The cam plates offered the ability to control the tooling device, the table in which the part is secured, as well as rotating the tooling or part within the machine. Due to the machines size and complexity it took extensive amounts of time to set them up for production. Once computer numerically controlled machining was introduced it provided a faster, more efficient method for machining complex parts.\nTypical CNC tools support translation in 3 axis; multiaxis machines also support rotation around one or multiple axis. 5-axis machines are commonly used in industry in which the workpiece is translated linearly along three axes (typically x, y, and z) and the tooling spindle is capable of rotation about an addition 2 axes.\nThere are now many CAM (computer aided manufacturing) software systems available to support multiaxis machining including software that can automatically convert 3-axis toolpaths into 5-axis toolpaths. Prior to the advancement of Computer Aided Manufacturing, transferring information from design to production often required extensive manual labor, generating errors and resulting in wasted time and material.\nThere are three main components to multiaxis machines:\nMultiaxis machines offer several improvements over other CNC tools, at the cost of increased complexity and price of the machine:\nThe number of axes for multiaxis machines varies from 4 to 9. Each axis of movement is implemented either by moving the table (into which the workpiece is attached), or by moving the tool. The actual configuration of axes varies, therefore machines with the same number of axes can differ in the movements that can be performed.\nApplications.\nMultiaxis CNC machines are used in many industries including:\nMultiaxis machining is also commonly used for rapid prototyping as it can create strong, high quality models out of metal, plastic, and wood while still being easily programmable.\nComputer-aided manufacturing (CAM) software.\nCAM software automates the process of converting 3D models into tool paths, the route the multiaxis machine takes to mill a part (Fig. 1). This software takes into account the different parameters of the tool head (in the case of a CNC router, this would be the bit size), dimensions of the blank, and any constraints the machine may have. The tool paths for multiple passes can be generated to produce a higher level of detail on the parts. The first few passes remove large amounts of material, while the final, most important pass creates the surface finish. In the case of the CNC lathe, the CAM software will optimize the tool path to have the central axis of the part align with the rotary of the lathe. Once the tool paths have been generated, the CAM software will convert them into G-code, allowing the CNC machine to begin milling.\nCAM software is currently the limiting factor in the capabilities of a multiaxis machine with ongoing development. Recent breakthroughs in this space include:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "8099541", "revid": "1138601687", "url": "https://en.wikipedia.org/wiki?curid=8099541", "title": "Pogo pin", "text": "A pogo pin or spring-loaded pin is a type of electrical connector mechanism that is used in many modern electronic applications and in the electronics testing industry. They are used for their improved durability over other electrical contacts, and the resilience of their electrical connection to mechanical shock and vibration.\nThe name \"pogo pin\" comes from the pin's resemblance to a pogo stickthe integrated helical spring in the pin applies a constant normal force against the back of the mating receptacle or contact plate, counteracting any unwanted movement which might otherwise cause an intermittent connection. This helical spring makes pogo pins unique, since most other types of pin mechanisms use a cantilever spring or expansion sleeve.\nA complete connection path requires a mating receptacle for the pin to engage, which is termed a \"target\" or \"land\". A pogo target consists of a flat or concave metal surface, which unlike the pins, has no moving parts. Targets may be separate components in the complete connector assembly, or in the case of printed circuit boards, simply a plated area of the board.\nSpring-loaded pins are precision parts fabricated with a turning and spinning process which does not require a mold, thus allowing the production of smaller quantities at a lower cost.\nStructure.\nA basic spring-loaded pin consists of 3 main parts: a \"plunger\", \"barrel\", and \"spring\". When force is applied to the pin, the spring is compressed and the plunger moves inside the barrel. The shape of the barrel retains the plunger, stopping the spring from pushing it out when the pin is not locked in place.\nIn the design of electrical contacts, a certain amount of friction is required to hold a connector in place and retain the contact finish. However, high friction is undesirable because it increases stress and wear on the contact springs and housings. Thus, a precise normal force, typically around 1 newton, is required to generate this friction. Since a spring-loaded pin needs to have a slight gap between the plunger and barrel so that it can slide easily, momentary disconnections can happen when there is vibration or movement. In order to counter this, the plunger usually has a small tilt to ensure a continuous connection.\nMany manufacturers have created their own proprietary variations on this design, most commonly by varying the interface between the plunger and spring. For example, a ball may be added between the two components, or the plunger may have an angled or countersunk tip.\nMaterials.\nThe plunger and barrel of pogo pins usually use brass or copper as a base material on which a thin layer of nickel is applied. \nAs common in electrical connectors, manufacturers often apply a gold plating that improves the durability and contact resistance.\nThe springs are usually made of copper alloys or spring steel.\nApplications.\nSpring-loaded connectors are used for a wide variety of applications, in both industrial and consumer electronics:\nConnector arrangement.\nWhen pogo pins are used in a connector, they are usually arranged in a dense array, connecting many individual nodes of two electrical circuits. They are commonly found in automatic test equipment in the form of a bed of nails, where they facilitate the rapid, reliable connection of the devices under test (DUTs). In one extremely high-density configuration, the array takes the form of a ring containing hundreds or thousands of individual pogo pins; this device is sometimes referred to as a \"pogo tower\".\nThey can also be used for more permanent connections, for example, in the Cray-2 supercomputer.\nWhen used in the highest-performance applications, pogo pins must be very carefully designed to allow not only high reliability across many mating/unmating cycles but also high-fidelity transmission of the electrical signals. The pins themselves must be hard, yet plated with a substance (such as gold) that provides for reliable contact. Within the body of the pin, the plunger must make good electrical contact with the body lest the higher-resistance spring carry the signal (along with the undesirable inductance that the spring represents). The design of pogo pins to be used in matched-impedance circuits is especially challenging; to maintain the correct characteristic impedance, the pins are sometimes arranged with one signal-carrying pin surrounded by four, five, or six grounded pins.\nCombination with magnets.\nSpring-loaded connectors may be combined with magnets to form a strong and reliable connectiona technique which has been employed extensively for consumer electronics such as 2-in-1 PCs and high-frequency data transfer. One notable example of this is Apple's MagSafe connector.\nCommercial products.\nAlthough often used as a generic name, \"pogo pin\" is a registered trademark of Everett Charles Technologies (ECT). ", "Engineering,_Manufacturing": 0.9998407364, "qwen": "Yes"}
{"id": "1418103", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=1418103", "title": "Manufacturing resource planning", "text": "Manufacturing resource planning (MRP II) is a method for the effective planning of all resources of a manufacturing company. Ideally, it addresses operational planning in units, financial planning, and has a simulation capability to answer \"what-if\" questions and is an extension of closed-loop MRP (Material Requirements Planning).\nThis is not exclusively a software function, but the management of people skills, requiring a dedication to database accuracy, and sufficient computer resources. It is a total company management concept for using human and company resources more productively.\nKey functions and features.\nMRP II is not a single specific proprietary software system and can thus take many forms. It is almost impossible to visualize an MRP II system that does not use a computer, but an MRP II system can be based on either purchased–licensed or in-house software.\nAlmost every MRP II system is modular in construction. Characteristic basic modules in an MRP II system are:\ntogether with auxiliary systems such as:\nand related systems such as:\nThe MRP II system integrates these modules together so that they use common data and freely exchange information, in a model of how a manufacturing enterprise should and can operate. The MRP II approach is therefore very different from the \"point solution\" approach, where individual systems are deployed to help a company plan, control or manage a specific activity. MRP II is by definition fully integrated or at least fully interfaced.\nMRP and MRPII.\nHistory and evolution.\nMaterial requirements planning (MRP) and manufacturing resource planning (MRPII) are predecessors of enterprise resource planning (ERP), a business information integration system. The development of these manufacturing coordination and integration methods and tools made today's ERP systems possible. Both MRP and MRPII are still widely used, independently and as modules of more comprehensive ERP systems, but the original vision of integrated information systems as we know them today began with the development of MRP and MRPII in manufacturing.\nMRP (and MRPII) evolved from the earliest commercial database management package developed by Gene Thomas at IBM in the 1960s. The original structure was called BOMP (bill-of-materials processor), which evolved in the next generation into a more generalized tool called DBOMP (Database Organization and Maintenance Program). These were run on mainframes, such as IBM/360.\nThe vision for MRP and MRPII was to centralize and integrate business information in a way that would facilitate decision making for production line managers and increase the efficiency of the production line overall. In the 1980s, manufacturers developed systems for calculating the resource requirements of a production run based on sales forecasts. In order to calculate the raw materials needed to produce products and to schedule the purchase of those materials along with the machine and labor time needed, production managers recognized that they would need to use computer and software technology to manage the information. Originally, manufacturing operations built custom software programs that ran on mainframes.\nMaterial requirements planning (MRP) was an early iteration of the integrated information systems vision. MRP information systems helped managers determine the quantity and timing of raw materials purchases. Information systems that would assist managers with other parts of the manufacturing process, MRPII, followed. While MRP was primarily concerned with materials, MRPII was concerned with the integration of all aspects of the manufacturing process, including materials, finance and human resources.\nLike today's ERP systems, MRPII was designed to tell us about a lot of information by way of a centralized database. However, the hardware, software, and relational database technology of the 1980s was not advanced enough to provide the speed and capacity to run these systems in real-time, and the cost of these systems was prohibitive for most businesses. Nonetheless, the vision had been established, and shifts in the underlying business processes along with rapid advances in technology led to the more affordable enterprise and application integration systems that big businesses and many medium and smaller businesses use today.\nGeneral concepts.\nMaterial requirements planning (MRP) and manufacturing resource planning (MRPII) are both incremental information integration business process strategies that are implemented using hardware and modular software applications linked to a central database that stores and delivers business data and information.\nMRP is concerned primarily with manufacturing materials while MRPII is concerned with the coordination of the entire manufacturing production, including materials, finance, and human resources. The goal of MRPII is to provide consistent data to all members in the manufacturing process as the product moves through the production line.\nPaper-based information systems and non-integrated computer systems that provide paper or disk outputs result in many information errors, including missing data, redundant data, numerical errors that result from being incorrectly keyed into the system, incorrect calculations based on numerical errors, and bad decisions based on incorrect or old data. In addition, some data is unreliable in non-integrated systems because the same data is categorized differently in the individual databases used by different functional areas. \nMRPII systems begin with MRP, material requirements planning. MRP allows for the input of sales forecasts from sales and marketing, or of actual sales demand in the form of customers orders. These demands determine the raw materials demand. MRP and MRPII systems draw on a master production schedule, the breakdown of specific plans for each product on a line. While MRP allows for the coordination of raw materials purchasing, MRPII facilitates the development of a detailed production schedule that accounts for machine and labor capacity, scheduling the production runs according to the arrival of materials. An MRPII output is a final labor and machine schedule. Data about the cost of production, including machine time, labor time and materials used, as well as final production numbers, is provided from the MRPII system to accounting and finance.\nFor the companies that want to integrate their other departments with their manufacturing management, ERP software are necessary.\nBenefits.\nMRP II systems can provide:\nFor design / engineering:\nFor financial and costing:\nCriticism.\nAuthors like Pochet and Wolsey argue that MRP and MRP II, as well as the planning modules in current APS and ERP systems, are actually sets of heuristics. Better production plans could be obtained by optimization over more powerful mathematical programming models, usually integer programming models. While they acknowledge that the use of heuristics, like those prescribed by MRP and MRP II, were necessary in the past due to lack of computational power to solve complex optimization models, this is mitigated to some extent by recent improvements in computers.", "Engineering,_Manufacturing": 1.0000038147, "qwen": "Yes"}
{"id": "14476004", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=14476004", "title": "Toyota Sportivo Coupe", "text": "The Toyota Sportivo Coupe is a concept car developed by Toyota Australia. The car is most notable for not only its decidedly high-tech design, but that it was designed by a group of teenagers (ages 14–18). Key design elements include a speedometer in which the speed limit always occupies the 12 o'clock position. It also features GPS, Bluetooth, and a Driver I.D. system which automatically configures the car to the drivers settings saved on the card. The entire vehicle was built in 30 weeks using CAD and rapid prototyping. The vehicle is built on top of a modular Toyota frame using a modified drive train from the Camry and RAV4.", "Engineering,_Manufacturing": 0.9990224838, "qwen": "Yes"}
{"id": "58269844", "revid": "202394", "url": "https://en.wikipedia.org/wiki?curid=58269844", "title": "Office of Production Management", "text": "The Office of Production Management was a United States Government agency that existed from January 1941 to centralize direction of the federal procurement programs and quasi-war production during the period immediately proceeding the United States' involvement in World War II. After the United States formally entered World War II, the War Production Board superseded the Office of Production Management in January 1942 and the office ceased to exist shortly thereafter. It was established and distestablished by Executive Order of President Franklin D. Roosevelt.", "Engineering,_Manufacturing": 0.9997678399, "qwen": "Yes"}
{"id": "11107815", "revid": "17881181", "url": "https://en.wikipedia.org/wiki?curid=11107815", "title": "Press brake", "text": "A press brake is a machine used for bending sheet metal and metal plate, most commonly sheet metal. It forms predetermined bends by clamping the workpiece between a matching top tool and bottom die.\nTypically, two C-frames form the sides of the press brake, connected to a table at the bottom and on a movable beam at the top. The bottom tool is mounted on the table, with the top tool mounted on the upper beam.\nTypes.\nA brake can be described by basic parameters, such as the force or tonnage and the working length. Additional parameters include the stroke length, the distance between the frame uprights or side housings, distance to the back gauge, and work height. The upper beam usually operates at a speed ranging from 1 to 15 mm/s.\nThere are several types of press brakes including nut-stop hydraulic, synchro hydraulic, electric and hybrid.\nHydraulic presses operate by means of two synchronized hydraulic cylinders on the C-frames moving the upper beam. Servo-electric brakes use a servo-motor to drive a ballscrew or belt drive to exert tonnage on the ram.\nHistorically, a mechanical press entailed with energy that was added to a flywheel with an electric motor. A clutch engages the flywheel to power a crank mechanism that moves the ram vertically. Accuracy and speed are two advantages of the mechanical press.\nUntil the 1950s, mechanical brakes dominated the world market. The advent of better hydraulics and computer controls have led to hydraulic machines being the most popular.\nTodays press brakes are controlled by two types of controls, NC (Numeric Controlled) or CNC (Computer Numeric Controlled). NC is a basic controller where the CNC is the high end controller although the initial outlay might be more than a NC, a CNC controller can be more effective, keeping cost down in the long run.\nPneumatic and servo-electric machines are typically used in lower tonnage applications. Hydraulic brakes produce accurate high quality products, are reliable, use little energy and are safer because, unlike flywheel-driven presses, the motion of the ram can be easily stopped at any time in response to a safety device, e.g. a light curtain or other presence sensing device.\nRecent improvements are mainly in the control and a device called a backgauge. A back gauge is a device that can be used to accurately position a piece of metal so that the brake puts the bend in the correct place. Furthermore, the back gauge can be programmed to move between bends to repeatedly make complex parts. Early brakes relied on the tooling to determine the bend angle of the bend. The animation to the right shows the operation of the back gauge, setting the distance from the edge of the material or previous bend to the center of the die.\nPress brakes often include multi-axis computer-controlled back gauges. They allow operators to position material correctly and sequence the bends step-by-step until completed. Optical sensors allow operators to make adjustments during the bending process. These sensors send real-time data about the bending angle in the bend cycle to machine controls that adjust process parameters.\nDies.\nPress brakes can be used for many different forming jobs with the right die design. Types of dies include:", "Engineering,_Manufacturing": 0.999994874, "qwen": "Yes"}
{"id": "11538102", "revid": "10044298", "url": "https://en.wikipedia.org/wiki?curid=11538102", "title": "Ball spline", "text": "Ball splines (Ball Spline bearings) are a special type of linear motion bearing that are used to provide nearly frictionless linear motion while allowing the member to transmit torque simultaneously. There are grooves ground along the length of the shaft (thus forming splines) for the ball bearings to run inside. The outer shell that houses the balls is called a nut rather than a bushing, but is not a nut in the traditional sense—it is not free to rotate about the shaft, but is free to travel up and down the shaft. For a shaft travel of any significant length the nut will have channels that recirculate the balls, operating in the same way as a ball screw. \nBy increasing the contact area of the ball bearings on the shaft to approximately 45 degrees, the side load and direct load carrying capabilities are greatly increased. Each nut can be individually preloaded at the factory to decrease the available radial play to ensure rigidity. This process not only increases the contact area, increasing direct loading capabilities, but it also restricts any radial movement, increasing the overhung moment capabilities. This creates a sturdier structure that can handle a very strenuous working environment.", "Engineering,_Manufacturing": 1.0000072718, "qwen": "Yes"}
{"id": "69098780", "revid": "27199084", "url": "https://en.wikipedia.org/wiki?curid=69098780", "title": "List of ventilator manufacturers", "text": "This is a list of notable ventilator manufacturers and businesses that manufacture ventilator components for the healthcare industry.", "Engineering,_Manufacturing": 0.9999924898, "qwen": "Yes"}
{"id": "7736707", "revid": "35710843", "url": "https://en.wikipedia.org/wiki?curid=7736707", "title": "Die (integrated circuit)", "text": "A die, in the context of integrated circuits, is a small block of semiconducting material on which a given functional circuit is fabricated. Typically, integrated circuits are produced in large batches on a single wafer of electronic-grade silicon (EGS) or other semiconductor (such as GaAs) through processes such as photolithography. The wafer is cut (diced) into many pieces, each containing one copy of the circuit. Each of these pieces is called a die.\nThere are three commonly used plural forms: \"dice\", \"dies,\" and \"die\". To simplify handling and integration onto a printed circuit board, most dies are packaged in various forms.\nManufacturing process.\nMost dies are composed of silicon and used for integrated circuits. The process begins with the production of monocrystalline silicon ingots. These ingots are then sliced into disks with a diameter of up to 300 mm.\nThese wafers are then polished to a mirror finish before going through photolithography. In many steps the transistors are manufactured and connected with metal interconnect layers. These prepared wafers then go through wafer testing to test their functionality. The wafers are then sliced and sorted to filter out the faulty dies. Functional dies are then packaged and the completed integrated circuit is ready to be shipped.\nUses.\nA die can host many types of circuits. One common use case of an integrated circuit die is in the form of a Central Processing Unit (CPU). Through advances in modern technology, the size of the transistor within the die has shrunk exponentially, following Moore's Law. Other uses for dies can range from LED lighting to power semiconductor devices.", "Engineering,_Manufacturing": 0.9998399019, "qwen": "Yes"}
{"id": "43597028", "revid": "1170592947", "url": "https://en.wikipedia.org/wiki?curid=43597028", "title": "Head-in-pillow defect", "text": "In the assembly of integrated circuit packages to printed circuit boards, a head-in-pillow defect (HIP or HNP) is a failure of the soldering process. For example, in the case of a ball grid array (BGA) package, the pre-deposited solder ball on the package and the solder paste applied to the circuit board may both melt, but the melted solder does not join. A cross-section through the failed joint shows a distinct boundary between the solder ball on the part and the solder paste on the circuit board, rather like a section through a head resting on a pillow.\nThe defect can be caused by surface oxidation or poor wetting of the solder, or by distortion of the integrated circuit package or circuit board by the heat of the soldering process. This is particularly a concern when using lead-free solder, which requires higher processing temperature.\nSince the warping of the circuit board or integrated circuit may disappear when the board cools, an intermittent fault may be created. Diagnosis of head-in-pillow defects may require use of X-rays or EOTPR (Electro Optical Terahertz Pulse Reflectometry), since the solder joints are hidden between the integrated circuit package and the printed circuit board.", "Engineering,_Manufacturing": 0.9998181462, "qwen": "Yes"}
{"id": "43612515", "revid": "35498457", "url": "https://en.wikipedia.org/wiki?curid=43612515", "title": "Cloud-based design and manufacturing", "text": "Cloud-based design and manufacturing (CBDM) refers to a service-oriented networked product development model in which service consumers are able to configure products or services and reconfigure manufacturing systems through Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS), Hardware-as-a-Service (HaaS), and Software-as-a-Service (SaaS).\nAdapted from the original cloud computing paradigm and introduced into the realm of computer-aided product development, Cloud-Based Design and Manufacturing is gaining significant momentum and attention from both academia and industry.\nCloud-based design and manufacturing includes two aspects: cloud-based design and cloud-based manufacturing. Another related concept is cloud manufacturing that is more general and popular.\nCloud-Based Design (CBD) refers to a networked design model that leverages cloud computing, service-oriented architecture (SOA), Web 2.0 (e.g., social network sites), and semantic web technologies to support cloud-based engineering design services in distributed and collaborative environments.\nCloud-Based Manufacturing (CBM) refers to a networked manufacturing model that exploits on-demand access to a shared collection of diversified and distributed manufacturing resources to form temporary, reconfigurable production lines which enhance efficiency, reduce product lifecycle costs, and allow for optimal resource allocation in response to variable-demand customer generated tasking.\nThe enabling technologies for Cloud-Based Design and Manufacturing include cloud computing, Web 2.0, Internet of Things (IoT), and service-oriented architecture (SOA).\nHistory.\nThe term cloud-based design and manufacturing (CBDM) was initially coined by Dazhong Wu, David Rosen, and Dirk Schaefer at Georgia Tech in 2012 for the purpose of articulating a new paradigm for digital manufacturing and design innovation in distributed and collaborative settings. The main objective of CBDM is to further reduce time and cost associated with\nmaintaining information and communication technology (ICT) infrastructures for design and\nmanufacturing, enhancing digital manufacturing and design innovation in distributed and collaborative environments, and adapting to rapidly changing\nmarket demands.\nIn 2014, the same research group also published the worldwide first two books on the subjects of Cloud-Based Design and Manufacturing (CBDM) and Social Product Development (SPD) with Springer, edited by Dirk Schaefer.\nCharacteristics.\nCBDM exhibits the following key characteristics:\nCBDM differs from traditional collaborative and distributed design and manufacturing systems such as web-based systems and agent-based systems from a number of perspectives, including (1) computing architecture, (2) data storage, (3) sourcing process, (4) information and communication technology infrastructure, (5) business model, (6) programming model, and (7) communication.\nService models.\nSimilar to cloud computing, CBDM services can be categorized into four major deployment models: the public cloud, private cloud, hybrid cloud, and community cloud.", "Engineering,_Manufacturing": 0.9999653101, "qwen": "Yes"}
{"id": "54094145", "revid": "1207711", "url": "https://en.wikipedia.org/wiki?curid=54094145", "title": "3D printer extruder", "text": "A 3D printer extruder is a filament feeding mechanism used in many fused filament fabrication (FFF) 3D printers. There are several types of 3D printer extruders. A Bowden extruder is a type of extruder that pushes filament through a long and flexible PTFE (Teflon) tube to the hot end. An alternative type of extruder which is also widely used in filament 3D printers is the direct-drive extruder, which sits closer to the extruder hot end.\nBowden extruder.\nBowden type extruders are easier to swap since they are outside the print head. They also have less chance of tangling the filament while it unwinds from the spool. Additionally, they reduce the mass of the extrusion carriage because it doesn't have to hold a stepper motor. This allows for faster changes in print head movement direction, increased print speed, increased accuracy, and decreased instances of artifacting or ghosting along the x and y axes.\nOne disadvantage is that because Bowden extruders push filament through a long and curved tube, more friction must be overcome compared with direct drive extruders. To partially mitigate these friction forces, the tube is made of PTFE, which has a low coefficient of friction. Flexible filaments do not print well because the filament flexes inside the tube and clogs up the machine.\nAnother disadvantage is that the feeding distance is relatively long, and thus the resistance is high, meaning the stepping motor of extrusion is required to have a higher torque. \nDirect-drive extruder.\nWith a direct-drive extruder, the motor pushing the filament is installed by the hotend and pushes the filament directly into the nozzle. Direct-drive designs have several advantages, and typically give better extrusion, faster retraction, are able to print more types of filaments, and can use a smaller and lighter motor due to the short distance to the nozzle. One typical disadvantage of direct-drive extruders is the added mass to the hotend, compared to a typical Bowden extruder, which may cause more vibrations so that the direct-drive printhead has to move slower, which can affect print speed. Another typical disadvantage is more complex maintenance due to tight packaging of many components in the hotend.", "Engineering,_Manufacturing": 0.9996856451, "qwen": "Yes"}
{"id": "13849149", "revid": "26830857", "url": "https://en.wikipedia.org/wiki?curid=13849149", "title": "Heyco", "text": "Heyco is a German tool manufacturing company which manufactures tools for the automotive industry. Heyco manufactures custom tooling for many German automotive production companies such as BMW, Audi, VW, and Mercedes Benz. Heyco also provides industrial automotive production support in the manufacturing of polymer parts, plastic foils, aluminum laminated fiberglass textures, long glass composites, synthetic leather and polyurethane foam parts.\nHeyco also manufactures electrical connector and wire protection systems for use in industrial and automotive applications.\nHistory.\nHeyco was founded in 1937 by Max and Ernst Heynen and started off manufacturing hand tools for the early automotive industry in Remscheid, Germany. After World War II, Heyco began production of tools for assembly line automobile production. Heyco expanded to Tittling/Bavaria, Germany in 1961, and to Derschen/Rheinland-Pfalz, Germany in 1981. Heyco Production facilities also operate in the Czech Republic, and Ireland.\nOEM Tool Kits.\nHeyco manufactures tools used in many TÜV European automobile tool kits, such as those found in Volkswagens, Opels, Fords, Volvos, BMWs, Mercedes Benzs, Rovers, Land Rovers and Rolls-Royces.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "5829477", "revid": "11877048", "url": "https://en.wikipedia.org/wiki?curid=5829477", "title": "1999 UEFA Intertoto Cup", "text": "The 1999 UEFA Intertoto Cup finals were won by Montpellier, Juventus, and West Ham United. All three teams advanced to the UEFA Cup.\nFirst round.\nSecond leg.\n\"Ventspils won 2–1 on aggregate.\"\n\"Sint-Truiden won 8–1 on aggregate.\"\n\"Polonia Warsaw won 4–0 on aggregate.\"\n\"4–4 on aggregate. Pobeda won 4–3 on penalties.\"\n\"2–2 on aggregate, Rudar Velenje won on away goals rule.\"\n\"MŠK Žilina won 4–0 on aggregate.\"\n\"Ararat Yerevan won 2–0 on aggregate.\"\n\"Varteks won 4–3 on aggregate.\"\n\"Vasas won 7–1 on aggregate.\"\n\"Neuchâtel Xamax won 2–0 on aggregate.\"\n\"Ceahlăul Piatra Neamţ won 2–0 on aggregate.\"\n\"1–1 on aggregate, Gomel won 3–1 on penalties.\"\n\"Newry Town won 2–1 on aggregate.\"\n\"2–2 on aggregate, Qarabağ won on away goals rule.\"\n\"Cementarnica 55 won 8–2 on aggregate.\"\n\"Basel won 6–0 on aggregate.\"\n\"Jedinstvo Bihać won 3–1 on aggregate.\"\n\"Floriana won 4–3 on aggregate.\"\n\"ÍA won 6–3 on aggregate.\"\n\"Jokerit won 7–1 on aggregate.\"\nSecond round.\nSecond leg.\n\"Perugia won 1–0 on aggregate.\"\n\"Duisburg won 2–1 on aggregate.\"\n\"Basel won 4–2 on aggregate.\"\n\"Rostselmash won 3–2 on aggregate.\"\n\"3–3 on aggregate; Varteks won 5–4 on penalties\"\n\"Austria Lustenau won 4–2 on aggregate.\"\n\"Lokeren won 6–2 on aggregate.\"\n\"Metz won 4–2 on aggregate.\"\n\"Polonia Warsaw won 4–1 on aggregate.\"\n\"Hammarby won 6–2 on aggregate.\"\n\"Kocaelispor won 3–1 on aggregate.\"\n\"Kocaelispor won 9–0 on aggregate.\"\n\"Sint-Truiden won 5–1 on aggregate.\"\n\"Vasas won 3–0 on aggregate.\"\n\"Jokerit won 3–0 on aggregate.\"\n\"Ceahlăul Piatra Neamţ won 5–2 on aggregate.\"\nThird round.\nSecond leg.\n\"Montpellier won 4–1 on aggregate.\"\n\"1–1 on aggregate, Juventus won on away goals rule.\"\n\"The game was abandoned in the 114th minute of extra time due to some objects being thrown on the pitch, some even hitting the referee. UEFA banned Perugia and awarded a 3–0 win to Trabzonspor.\"\n\"Trabzonspor won 4–2 on aggregate.\"\n\"West Ham United won 2–1 on aggregate.\"\n\"Heerenveen won 4–0 on aggregate.\"\n\"2–2 on aggregate, Rennes won on away goals rule.\"\n\"3–3 on aggregate, Hamburg won on away goals rule.\"\n\"Austria Wien won 3–2 on aggregate.\"\n\"2–2 on aggregate, Rostselmash won on away goals rule.\"\n\"Duisburg won 3–0 on aggregate.\"\n\"2–2 on aggregate, Metz won on away goals rule.\"\n\"Polonia Warsaw won 4–1 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Montpellier won 3–1 on aggregate.\"\n\"Hamburger SV won 6–3 on aggregate.\"\n\"Juventus won 9–1 on aggregate.\"\n\"Rennes won 4–2 on aggregate.\"\n\"West Ham United won 2–0 on aggregate.\"\n\"Metz won 6–2 on aggregate.\"\nFinals.\nSecond leg.\n\"2–2 on aggregate; Montpellier won 3–0 on penalties\"\n\"West Ham United won 3–2 on aggregate.\"\n\"Juventus won 4–2 on aggregate.\"", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "5841422", "revid": "1143671501", "url": "https://en.wikipedia.org/wiki?curid=5841422", "title": "Two-liter bottle", "text": "The two-liter bottle is a common container for soft drinks, beer, and wine. These bottles are produced from polyethylene terephthalate, also known as PET plastic, or glass using the blow molding process. Bottle labels consist of a printed, tight-fitted plastic sleeve. A resealable screw-top allows the contents to be used at various times while retaining carbonation.\nIn the United States, the two-liter bottle is one of the few cases where a product is sold by a round number of metric units. Since very few other beverages are sold in this exact quantity, the term \"two-liter\" in American English almost invariably refers to a soft drink bottle. Other common metric sizes for plastic soft drink bottles include 500 milliliters, 1 liter, and 3 liters.\nHistory.\nPepsiCo introduced the first two-liter sized soft drink bottle in 1970. Motivated by market research conducted by new marketing vice president John Sculley (who would later be known for heading Apple Inc. from 1983 to 1993), the bottle and the method of its production were designed by a team led by Nathaniel Wyeth of DuPont, who received the patent in 1973. In 1985, a three-liter bottle appeared on supermarket shelves. The design is still used to this day by some bottlers. \nMost modern-day two-liter bottles are one piece of PET (polyethylene terephthalate) with a base that is molded with a radial corrugation to provide strength for the bottom and the ability to stand upright. Most early two-liters had a separate opaque base glued to the hemispherical bottom of the clear PET flask. This base had a coaxial corrugation and drain holes.\nRecycling.\nUsed two-liter bottles see new life in a variety of uses including carpeting, boat hulls, polyester fabric, filling for jackets, sleeping bags, mattresses, pillows, recycling bins, artificial floating islands, scouring pads, and, on an increasing scale, new soft drink bottles.\nSpecifications.\nTypical dimensions:", "Engineering,_Manufacturing": 0.9998657703, "qwen": "Yes"}
{"id": "5845752", "revid": "473593", "url": "https://en.wikipedia.org/wiki?curid=5845752", "title": "Tecnomatix", "text": "Tecnomatix Technologies, Ltd. (formerly NASDAQ: TCNO) is a provider of Manufacturing Process Management and Product lifecycle management software to the electronics, automotive, aerospace and heavy equipment industries, currently owned by Siemens AG. Tecnomatix's eMPower is a suite of end-to-end Manufacturing Process Management solutions for the collaborative development and optimization of manufacturing processes across the extended enterprise and supply chain.\nHistory.\nFounded in Israel in 1983, the Tecnomatix Corporation provided Manufacturing Process Management (MPM) solutions for the automotive, electronics, aerospace and other manufacturing and processing industries. The Tecnomatix products suite offered software and services in all process monitoring and control, production management and execution.\nShlomo Dovrat was the founder of Tecnomatix and served as CEO and President from its inception until 1995. In 1993, Dovrat led Tecnomatix's IPO on the NASDAQ (TCNO). He served as Chairman of the Board of Directors from 1995 until December 2001. In 1994, Dovrat was succeeded as CEO by Harel Beit-On (also the company's President. In 2001 Beit-On was appointed Chairman of the Board of Directors, and served as Chairman until the company's acquisition in 2005.\nIn 1999, Tecnomatix acquired Unicam Software Inc., a provider of production engineering software to the printed circuit board (PCB) assembly market.\nIn 2003, Tecnomatix acquired USDATA Corporation. USDATA was the creator of the supervisory-level control (SCADA) product FactoryLink, and the manufacturing execution systems (MES) product Xfactory.\nIn 2005, Tecnomatix was acquired by the UGS Corporation and the Tecnomatix product was combined with UGS' existing MPM solutions. The current Tecnomatix software line includes Part Manufacturing, Assembly Planning, Resource Planning, Plant Simulation, Human Performance, Quality, Production Management, Manufacturing Data Management.\nIn January 2007 UGS was purchased by Siemens AG, and today the Tecnomatix solutions are available from Siemens Digital Industries Software. Siemens Digital Industries Software announced Tecnomatix version 9 in June 2009.", "Engineering,_Manufacturing": 0.9997757077, "qwen": "Yes"}
{"id": "1778592", "revid": "33049997", "url": "https://en.wikipedia.org/wiki?curid=1778592", "title": "ColdHeat", "text": "ColdHeat was an American company founded to develop and market products using the proprietary graphite-like compound Athalite. The composite material is claimed by the manufacturer to have the unusual ability to conduct large amounts of heat and return to room temperature in a short amount of time.\nSoldering iron.\nThe first two products were soldering irons powered by alkaline batteries. The manufacturer claims this soldering iron is unique in that its Athalite tip undergoes a temperature change from ambient temperature to approximately and back to ambient within three seconds when the tip is removed from the work. \nThe tip of this apparatus is split into two sections that completes an electrical circuit when a low electrical resistance is placed across the tip; e.g. metallic contacts, or solder. With a current flowing, the resistance of both the solder and the tip produces enough heat to increase the temperature beyond the melting point of solder. For the light-duty work it was designed for, the Athalite tip heats just enough and can cool very rapidly; however, if applied to something with large thermal capacity such as a metal chassis, the tip can become extremely hot and can take over a minute to cool in an extreme case.\nIt is thought that the irons cannot be used indiscriminately for all work; the voltage across and current through the tip can damage electronic circuits being soldered. When not in contact with a joint, the split tip has 6 or more volts across it, enough to destroy semiconductor p-n junctions on contact \"if the iron accidentally touches multiple closely spaced pads\". This is not static-electricity damage; any voltage over about 0.7V capable of delivering high current can destroy a semiconductor junction.\nAccording to ColdHeat:\nIt's a common misunderstanding that high current in the joint causes the heat. The heat is generated by resistance within the tip. Heat is then conducted to the joint just as in traditional solder tools. Also, current in the joint is limited to the small region between the two tip halves and doesn't pass through the part being soldered. There is a tiny transient voltage when the tool is applied or removed, but it is orders of magnitude below the levels that cause static-electricity damage.\nCriticism.\nThe tip is reported to be very easily damaged mechanically. The unit does not have enough power for effective desoldering of many board- and chassis-mounted components. The design of the tip is incompatible with some soldering techniques such as dragging or continuous-flow soldering (a popular technique for hand-soldering high-pin-count SMT packages, based on the principles of wave soldering).\nOne thorough review of the ColdHeat soldering iron noted:\nAthalite.\nAthalite is a highly malleable, yet fragile, composite material. The name is derived from \"Accelerated THermal Action\". It is most likely composed of graphite. It might also be formed by other materials containing semiconductive elements such as germanium or silicon, as stated in the patent application. A nickel-chromium or other resistive alloy is another possibility listed in the application, but is unlikely to have been used.\nOther products.\nPrior to the website's closure, ColdHeat featured products other than the soldering tool that use the same technology, including a cordless hot-melt glue gun called Freestyle. It heats up much more quickly than others (but not instantly like the solder tool.) It comes with a built-in stand, a pack of mini glue sticks, rechargeable battery, battery charger with its AC adapter, and an instructional manual and a book with different project ideas. However, much like the soldering tool, the Freestyle also had quality issues, usually related to the battery charge, and the heating element. There is a model that runs on AA batteries, for those who prefer their convenience.\nColdHeat had recently released a cordless heated seat, as well as a selection of heated pet beds.\nCurrent status.\nColdHeat signed a licensing deal with Weller/Cooper Tools in November 2005. Weller sold the ColdHeat Pro as the Weller CHT100. ", "Engineering,_Manufacturing": 1.0000008345, "qwen": "Yes"}
{"id": "37355422", "revid": "44386839", "url": "https://en.wikipedia.org/wiki?curid=37355422", "title": "Virtual manufacturing network", "text": "A Virtual Manufacturing Network is a manufacturing network which is not owned by a simple company, but it is built with the use of ICT for bringing together different suppliers and alliance partners creating in such a way a virtual network which is able to operate as a solely owned supply network. \nA Virtual Manufacturing Network is in this way a Collaborative network of manufacturing enterprises (from OEMs to Suppliers), which are connected by means of ICT for configuring, managing and monitoring the manufacturing process.\nMany companies have adopted a philosophy of acquiring worldwide resources through a virtual network for minimizing expenses in their whole operation, focusing on core competences and relying to other companies with specific expertise to take over the parts of the manufacturing process they cannot perform by themselves.\nThe evolution of a Virtual Manufacturing Network is a Dynamic Manufacturing Network, which describes a more flexible and agile manufacturing network, that is able to be instantiated or dissolved quite rapidly, in order to meet emerging market needs and business opportunities.", "Engineering,_Manufacturing": 1.0000059605, "qwen": "Yes"}
{"id": "28980455", "revid": "40854028", "url": "https://en.wikipedia.org/wiki?curid=28980455", "title": "Toyota Motor Manufacturing Turkey", "text": "Toyota Motor Manufacturing Turkey (TMMT) is one of Toyota's vehicle production bases in Europe. It is located in Adapazarı, Sakarya, Turkey, and has been manufacturing the Corolla (since 1994), the Corolla Verso, the Verso (2009–2018), the Auris (2007–2012), and the Toyota C-HR (2016–present). A majority of the production is exported to over 30 countries, most of which are in Europe.\nTMMT, owned by Toyota Motor Europe NV/SA (90%), and Mitsui & Co., Ltd. (10%), has a total investment of , and currently employs around 5,400 people.\nToday, with an annual production capacity of 280,000 units, Toyota Motor Manufacturing Turkey (TMMT) is one of Toyota's biggest plants in Europe operations, and one of Turkey's biggest manufacturing companies.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "29006350", "revid": "20958214", "url": "https://en.wikipedia.org/wiki?curid=29006350", "title": "Keithley Instruments", "text": "Keithley Instruments is a measurement and instrument company headquartered in Solon, Ohio, that develops, manufactures, markets, and sells data acquisition products, as well as complete systems for high-volume production and assembly testing.\nIn September, 2010, the company agreed to sell itself to the Danaher Corporation, a Washington, D.C.-based conglomerate, for $21.60 per share. It was soon merged with Tektronix, Inc, which had been acquired by Danaher in 2007, and now exists wholly as a brand of Tektronix.\nHistory.\nJoseph F. Keithley founded Keithley Instrument in 1946. His first product, the \"Phantom Repeater,\" amplified low-level electric signals so that they could be measured by more standard equipment. The device was used by physicists, chemists, and engineers in the development of hearing aids and amplifiers. The product enjoyed some success in sales, but it was the next product, an electrometer, that clinched the future for Keithley's fledgling company.\nGeneral.\nThe company designs, develops, manufactures and markets electronic instruments and systems geared to the specialized needs of electronics manufacturers for production testing, process monitoring, product development, and research.\nThe company has approximately 500 products used to source, measure, connect, control or communicate direct current (DC), radio frequency (RF), or optical signals. Product offerings include integrated systems solutions, instruments, and personal computer (PC) plug-in boards that can be used as system components or as stand-alone solutions.\nThe company's markets are engineers, technicians, and scientists in manufacturing, product development, and research functions.\nKeithley operates throughout North America, Asia, and Europe. It develops new solutions for the broader electronics industry, as well as electronic manufacturing production test, semiconductor, telecommunications/wireless and research/education.\nProducts.\nKeithley Instruments' major product lines included testing and measurement products such as electrometers, voltmeters, signal generators, data acquisition, and production and benchtop parametric testers and analyzers.", "Engineering,_Manufacturing": 0.998957932, "qwen": "Yes"}
{"id": "2732562", "revid": "1096297296", "url": "https://en.wikipedia.org/wiki?curid=2732562", "title": "Spin casting", "text": "Spin casting, also known as centrifugal rubber mold casting (CRMC), is a method of utilizing inertia to produce castings from a rubber mold. Typically, a disc-shaped mold is spun along its central axis at a set speed. The casting material, usually molten metal or liquid thermoset plastic, is then poured in through an opening at the top-center of the mold. The filled mold then continues to spin as the metal (or thermoset plastic) solidifies.\nGeneral description.\nThe two defining characteristics of spin casting are semi-permanent (non-expendable) rubber molds, and the use of inertial force. These make the process relatively unique compared to machined die-based and expendable mold casting methods. These qualities enable operators to design original models using media such as polymer clay that has an easy to carve Plasticine like consistency that when heated using a conventional oven, it hardens enough to hold up under the vulcanization process, producing an original mold where models are then cast for the production mold. These qualities also encourage operators to use casting materials specially formulated for low melting points and viscosities. Most spin casting is done with pewter and zinc alloys or thermoset plastics.\nSilicone molds.\nThe spin casting process typically uses vulcanized silicone or organic rubber as the mold-making substrate. Vulcanization is an integral step that occurs halfway through the mold-making process. Prior to vulcanization, the mold rubber is a soft and malleable solid-like fluid, in many ways very similar to Silly Putty. Because of the clay-like nature at this stage, the mold is easily cut or shaped to accommodate irregular models. Vulcanization serves two purposes: establishing the negative space inside the mold as well as hardening the rubber so it will remain strong and rigid during casting. \nAfter vulcanization, before it is usable, the mold must undergo gating and venting. This involves carving channels to ensure proper air and material flow during the casting process. Gating and venting is typically done by hand using a sharp knife or scalpel and varies in time depending upon the complexity of the mold. The final product is a cured rubber mold, which can withstand anywhere from hundreds to over a thousand casting cycles before replacement is needed. \nCasting materials.\nMetal.\nGenerally, the casting materials used for competing processes like metal die casting and injection molding are similar, but not suitable for spin casting. For example, a typical zinc die-casting alloy such as Zamak 3 can be used but will solidify too rapidly from a molten state when cast with centrifugal force. This typically results in incomplete filling of the mold as well as a rough, porous finish, called orange peel. Zamak 2, of a slightly different composition, was originally developed as a gravity-cast alloy with greater finished strength but was found to work well with spin-casting. Its extra copper content encourages the eutectic behaviour and gives a lower freezing point. It has become known as 'Kirksite' and has given rise to a range of dedicated spin-casting alloys, some with additional components, such as magnesium, to control the surface finish. \nTo ensure replicable casting cycles of accurate reproductions with a high quality finish, the spin casting process requires casting materials with the following qualities, for the following reasons: \nPlastic.\nAside from the aforementioned metal alloys, thermoset resins and plastics work well with spin casting as they can be introduced as liquids and will set or solidify while the mold spins. In general, spin casting encourages the use of casting materials that are liquid upon introduction to the mold and solidify at a slow, uniform rate during the spin cycle.\nEquipment.\nSpin caster.\nDuring the casting process, the finished mold spins along its central axis for anywhere from 30 seconds to several minutes depending upon the chosen casting material. Internally, a spin casting machine or spin caster consists of a motor and pressure clamping system, which holds and positions the mold properly while it spins at a steady rate. These components are placed inside of a machine body, which shields against flashing of molten metal or liquid plastic that is inadvertently ejected from the mold during the spinning process. Without the proper containment, hot melted flashing can be a serious hazard to nearby persons. \nCommercial spin casting machines are available in two different types, front-loading and top-loading. Owing to the weight and bulkiness of spin casting molds, front loading machines tend to offer several advantages regarding ease of use and time savings. Rubber molds can become quite heavy, especially at larger diameters and when casting metal. Because loading and unloading the caster is performed by hand, it is easiest and less fatiguing to manipulate the mold at waist level in one fluid motion as allowed by a front-loading spin caster. This is important in production spin casting, to maximize the number of casting cycles per hour. \nTop loading machines tend to be cheaper and theoretically have less of a restriction on maximum mold thickness.\nVulcanizer.\nVulcanization is a necessary step to prepare the uncured silicone mold for spin casting. Under controlled heat and pressure the silicone slowly cures to a heat-resistant, flexible, permanent mold. The vulcanizing press or vulcanizer uniformly compresses the mold while exposing it to heat for several hours. The vulcanizer consists of a pair of parallel heated platens mounted on a hydraulic press. Smaller or home-made vulcanizers may compress the mold via screws or a heavy duty clamp instead of hydraulic pressure. Some spin casting operations choose to forgo running their own vulcanizer and procure molds from a supplier.\nMelting furnace.\nA melting furnace is necessary only when spin casting metal. The metal must be molten prior to introduction into the mold. It is necessary for a spin casting furnace to have a temperature controller, as there is an optimal range for each metal. For example, a particular zinc alloy is typically cast between 775 and 800 °F, whereas it actually melts much lower around 500 °F. If the metal is introduced to the mold at a higher temperature (in this case, above 800 °F), it will wear the silicone prematurely, shortening the mold life. If the metal is introduced at significantly lower temperatures (below 775 °F), its solidification time will similarly be shortened resulting in incomplete or low quality castings. Spin casting metal requires a furnace with fine temperature control, and knowledge of proper casting temperature.\nSimilar processes.\nSpin casting is a favored method for fabricating items in the specified materials – low temperature metals and thermoset plastics. Compared to the two main competing processes, injection molding and (zinc) die-casting, spin casting has significant advantages in terms of startup cost and ease of use. In some cases, spin casting can also be an alternative to sand casting, plaster mold casting or investment casting. These three techniques (sand, plaster and lost wax) are not directly comparable as each utilizes an expendable mold. \nThe remarkable disparity in tooling cost and lead time is a result of the expensive and time-consuming machining required to produce the precision metal molds (dies) used with die-casting and plastic injection molding. The precision tooling and resilient nature of the machined metal die yields an extremely long-lasting mold and slight improvements to casting tolerances. Thermoplastics and die casting metal alloys are in wider use than their specialized spin casting analogs, and are typically cheaper.\nApplications.\nSpin casting is commonly used for the manufacture of the following types of items: \nBecause of low start up costs and ease of use, spin casting is available to individuals and businesses unable to make the deep investments required by die casting, injection molding or similar processes. These users include smaller business and design houses that would normally contract their work to production \"job\" shops, as well as hobbyists producing unique items for personal enjoyment. Thus, spin casting is accessible to a broader range of applications than competing technologies.", "Engineering,_Manufacturing": 0.9999469519, "qwen": "Yes"}
{"id": "32163102", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=32163102", "title": "Enterprise control", "text": "Enterprise control is the ability to combine control, intelligence and process management to enable business optimization that is inclusive of business and production operations. It combines the strength of both business processes and production operations processes. It is the deliberate act of synchronizing business strategy with operational execution in real-time to enable closed loop business control across an enterprise.\nKey elements.\nInteroperating enterprise and industrial service-oriented architectures (SOA) provide industrial companies with the potential for problem solutions that cover entire plants and entire industrial enterprises. This enterprise-wide system can be developed using systems and technologies previously installed. The resulting system, consisting of multiple vendor products acquired over many years working as a single system, is what is referred to as an enterprise control system.\nThe enterprise control strategy is built around the premise that manufacturing needs an enterprise control system to integrate business systems and manufacturing in real-time. The concept of the enterprise control system encompasses everything from sensors and people in manufacturing to the ERP system.\nAn enterprise control system is the open architecture framework to integrate control systems with the enterprise while adding functions to improve business performance including MES, optimization, workflow, quality management, and asset management.\nHistory.\nA distributed control system gave way to process automation systems which lead the way for the concept of collaborative automation process systems developed by ARC Advisory Group\nLater, enterprise control systems became key terminology in the marketplace.\nANSI/ISA-95 Enterprise-Control System Integration, or ISA-95 (known internationally as IEC 62264) is an international standard for developing an automated interface between enterprise and control systems. This standard has been developed for global manufacturers. There are five levels and It was developed to be applied in all industries, and in all sorts of processes, like batch processes, continuous and repetitive processes.\nISA95 “levels” for enterprise integration.\nPurdue Reference Model, “95” provides a model that end users, integrators and vendors can share in integrating applications at key layers in the enterprise. This model influenced the ISA-95 (International Society of Automation) enterprise-control integration standards, which expanded on the terms of the Purdue Reference Model and describes the interface between enterprise and control systems.", "Engineering,_Manufacturing": 1.0000054836, "qwen": "Yes"}
{"id": "32173564", "revid": "45781585", "url": "https://en.wikipedia.org/wiki?curid=32173564", "title": "Lean product development", "text": "Lean product development (LPD) is a lean approach to counter the challenges of product development, notably:\nHistory of lean product development.\nToyota started its journey with lean product development at Toyota Loom Works (see History of Toyota). Their early approach is notably different from Lean manufacturing that became famous through the book \"The Machine that changed the world\".\nWhen Toyota started manufacturing cars, there was a difference in manufacturing conditions between Japan and the USA. Toyota had few educated engineers and little prior experience. Car companies in US employed a well-educated work force in the cities and benefited from the research and student skill-sets of established engineering schools. To tackle this shortfall in knowledge and experience, Toyota conducted an incremental approach to development that built on their existing knowledge and became the basis of the lean systems Toyota uses today.\nAllen Ward studied Toyota’s lean product development system and found parallels with the US airplane industry. For instance, the Wright brothers’ method of constructing their airplanes became one of the legacies they passed on to the aviation industry. This approach enabled the USA to create one of World War II's most successful fighter planes from scratch in the short span of six months. After the war, Toyota incorporated many of the airline industry's findings into its own product development methodology.\nDifferences between lean product development and lean production.\nWhile some basic principles and guidelines are applicable across Lean product development and Lean production (such as waste reduction), many applications of lean process for development have focused more on the production approach.\nThe purpose of production is to manufacture products reliably within margins of control. The flow of value is physically evident, and the link between cause and effect is easy to see. For example, feedback on adjusting the speed of production is immediately realized in an increase or decrease in rejected items. Any decisions made must be based on best practice.\nOn the other hand, the purpose of product development is to design new products that improve the lives of customers. This is a complex space where the flow of value can only be discerned at an abstract level and where cause and effect might be separated by time and space. For example, feedback on the decision to design a certain feature will not be received until the product has been built and is in the hands of the customer. This means that decisions are made on short-cycle experimentation, prototyping, set-based design, and emergent practice. A premium is placed on creating reusable knowledge and reducing risk at handover points.\nAn essential point about these differences is summarized in the advice Jim Womack gives Harley Davidson: \"Don't try to bring lean manufacturing upstream to product development. The application of Lean in product development and manufacturing are different. Some aspects may look similar, but they are not! Be leery of an expert with experience in lean manufacturing that claims to know product development\" \nThe most common high level concepts associated with lean product development are:\nResults of lean product development.\nLean product development has been claimed to produce the following results:\nCompanies such as Toyota can attribute their success to lean product development. In 2000, Toyota launched 14 new products, a larger product line than GM's entire product offering. At that point, Toyota had just 70,000 employees while GM had more than five times as many.\nApplicability of lean product development.\nResearchers divide product development projects accordingly to their need drivers:\nFor example, the mobile phone was a \"Wanted\" product in the 1990s because it was on the leading edge of technology. Today it is regarded as a \"Needed\" product. It is common in the market. There is enough knowledge in the public domain so that even small companies can make a good mobile phone.\nProduct development methods can be classified according to whether they are focused on handling stable or non-stable conditions. Lean product development is a dynamic method of product development that handles unstable conditions.\nThe influence of need drivers and stability (or lack of stability) on product development are illustrated in the table below.\nNotes and references.\nExchange ref 12 with:\nOttosson, S. (2016): Developing Sustainable Product Innovations, page 112", "Engineering,_Manufacturing": 1.0000076294, "qwen": "Yes"}
{"id": "1359546", "revid": "1158812177", "url": "https://en.wikipedia.org/wiki?curid=1359546", "title": "Mandrel", "text": "A mandrel, mandril, or arbor is a tapered tool against which material can be forged, pressed, stretched or shaped (e.g., a ring mandrel - also called a triblet - used by jewellers to increase the diameter of a wedding ring), or a flanged or tapered or threaded bar that grips a workpiece to be machined in a lathe. A flanged mandrel is a parallel bar of a specific diameter with an integral flange towards one end, and threaded at the opposite end. Work is gripped between the flange and a nut on the thread. A tapered mandrel (often called a plain mandrel) has a taper of approximately 0.005 inches per foot and is designed to hold work by being driven into an accurate hole on the work, gripping the work by friction. A threaded mandrel may have a male or female thread, and work which has an opposing thread is screwed onto the mandrel.\nOn a lathe, mandrels are commonly mounted between centres and driven by a lathe dog (typically flanged or tapered mandrels), but may also be gripped in a chuck (typically threaded mandrels) where the outer face of work is to be machined. Threaded mandrels may also be mounted between centres.\nIn addition to lathes, mandrels, more usually referred to as “arbours” are used to hold buffing wheels, circular saws, and sanding discs. Typically, such mandrels consist of a cylinder that is threaded on one end. There are many different types of mandrels for specialised applications. Examples include live chuck mandrels, live bull ring mandrels, and dead bull ring mandrels.\nVariants.\nIn machining.\nAn example of one type of mandrel is a shaped bar of metal inserted in, or next to, an item to be machined or bent in a certain pattern, e.g. in drawing metal tubing. Exhaust pipes for automobiles are frequently bent using a mandrel during manufacture. The mandrel allows the exhaust pipes to be bent into smooth curves without undesirable creasing, kinking, or collapse. Molten glass may also be so shaped. \nA chuck is used on a lathe to hold pieces of wood, metal or plastic to be machined as they are turned. In this way, rods can be threaded, furniture legs are turned to a desired shape, and irregularly-shaped objects can be given a round shape. Several types of mandrel are used with lathes. Original expanding mandrels have a slightly tapered wedge that will expand to hold the item.\nA third type of mandrel is that which is used to hold circular saw blades, buffing wheels (used for polishing), and sanding discs onto drills, circular saws, and similar power tools. A mandrel of this type generally consists of a cylinder, threaded on one end, with a washer brazed onto the threaded end and an accompanying screw and second washer used to clamp the circular saw blade, sanding media, or other rotary tool onto the mandrel.\nWhile most mandrels are driven by direct connection to an electric motor or other engine, other mandrels may be driven by attachment to a bearing-supported, pulley-driven shaft.\nIn jewelry.\nA 'triblet' is a type of mandrel found in jewelry manufacturing that is not inserted into or held by a machine. Such mandrels vary in sizes and shapes, from small tapered metal rods (ring mandrels) to free-standing metal conic sections (used for making bracelets). Unlike with mechanical mandrels, the process is performed by hand. When shaping a ring or bangle with a triblet, it is typical to bend and solder the metal into a rough loop, then place it over the thinner end of the mandrel. Once done, the next step is to strike the work in a downward motion with a hammer or other tool to push it towards the wider end. This forces the metal to adopt a true ring-shape. Triblets with measurements cut into them (called 'ring size sticks') can also be used as a quick way of measuring the final size of a ring. A triblet can also be used to make a ring slightly bigger by gently tapping it in order to force it down the cone - thus stretching the metal. Triblets are also used to repair squashed or damaged rings.\nIn music.\nA type of mandrel is also used in making reeds for double reed instruments such as the bassoon or oboe. \nUses.\nMandrels are also used in industrial composite fabrication such as in filament winding. During the manufacturing process, resin-impregnated filaments are wound around a mandrel to create a composite material structure or part. The structure is cured and the mandrel is removed. One problem with this type of process is difficulty in removing the mandrel from the completed work. A mandrel with a changeable shape can be more easily extracted. When heated above a certain temperature, the mandrel becomes elastic and can be manipulated into the desired shape and then cooled to become rigid again in the new shape. It can then be used in the filament winding process. Once the composite part is cured, the mandrel can be reheated until elastic and easily removed from the cured part. These types of mandrels can be used repeatedly.\nIn the production of steel core used for flexible drives, the center wire upon which the subsequent layers are wound is referred to as a Mandrel. This \"center wire\" may itself be composed of either a single wire or layers, depending on the sizing of the finished product.\nA hole saw usually attaches to a mandrel, the latter being basically a drill bit with threads to secure the saw.\nHistory.\nMandrels are not recent inventions. Metal machining utilizing the spinning process has been recorded as far back as ancient Egyptian times. In metal spinning, a wood or metal spinning mandrel is used, the form of which corresponds with the internal contour of the part to be produced. This method securely clamps the raw material and allows for accurate machining into the desired final form. Since the material is clamped internally, there is no interference to the operator from the lathe/mandrel assembly during production.\nThe \"traversing mandrel\" was introduced around 1700, and instantiated the design of a lathe mandrel able to slide axially in its bearings under the control of the operator, so that components having short lengths of thread could be produced, such as screws. The traversing mandrel was primarily employed by watchmakers and ornamental turners during this era. Eventually the device was superseded by a mandrel-driven device called a leadscrew, which uses a train of gears that can be altered as required for the turning application.", "Engineering,_Manufacturing": 0.9999990463, "qwen": "Yes"}
{"id": "14538480", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=14538480", "title": "Product-service system", "text": "Product-service systems (PSS) are business models that provide for cohesive delivery of products and services. PSS models are emerging as a means to enable collaborative consumption of both products and services, with the aim of pro-environmental outcomes.\nDescription.\nProduct service systems, put simply, are when a firm offers a mix of both products and services, in comparison to the traditional focus on products. As defined by (van Halen, te Riele, Goedkoop) \"a marketable set of products and services capable of jointly fulfilling a user's needs\", PSSes can be realized by smart products.\nThe initial move to PSS was largely motivated by the need on the part of traditional manufacturing firms to cope with changing market forces and the recognition that services in combination with products could provide higher profits than products alone. Faced with shrinking markets and increased commoditization of their products, these firms saw service provision as a new path towards profits and growth.\nWhile not all product service systems result in the reduction of material consumption, they are more widely being recognized as an important part of a firm's environmental strategy. In fact, some researchers have redefined PSS as necessarily including improved environmental improvement. For example, Mont defines PSS as \"a system of products, services, supporting networks, and infrastructure that is designed to be competitive, satisfy customers' needs, and have a lower environmental impact than traditional business models.\" Mont elaborates on her definition as follows: A PSS is a pre-designed system of products, services, supporting infrastructures, and necessary networks that is a so-called \"dematerialized\" solution to consumer preferences and needs. It has also been defined as a \"self-learning\" system, one of whose goals is continual improvement.\nThis view of PSS is similar to other concepts commonly seen in the environmental management literature, such as \"dematerialization\" and \"servicizing\".\nPSS has been used to create value for customers beyond selling products as functions. Typically, there are four approaches to PSS design.\nThere are many methodologies on PSS design. Dominant Innovation system uses an Innovation Matrix to identify gaps from customer's fear, not needs based on scenario-based path finding. A new value-chain ecosystem can be further developed to link these gaps between two invisible spaces. For example, John Deere developed Agric Service business based on the customers' worries on soil related issues. It integrates sensors with GPS to develop cognitive site map about soil content to optimize crop yields. Several peer-reviewed scientific articles have reviewed and give an overview of the PSS design research field.\nIn recent years, PSS has been further integrated with big data analytics for accelerated innovation. Other technologies such as prognostics, health management and cyber-physical systems have further created service innovation technologies for PSS. For example, Alstom has been developing Train Tracer technologies since 2006 and is implementing Health Hub system for its transport fleets.\nServicizing.\n\"Servicizing\" is a transaction through which value is provided by a combination of products and services in which the satisfaction of customer needs is achieved either by selling the function of the product rather than the product itself, or by increasing the service component of a product offer. The concept is based on the idea that what customers want from products is not necessarily ownership, but rather the function that the product provides or the service the product can deliver. This means that the provider of \"servicizing solutions\" may get paid by the unit-of-service (or product function) delivered, as opposed to the (more traditional) unit-of-products sold. \"See service economy for more on the servitization of products.\"\nOne type of servicizing solutions is based on transactions where payment is made—not for the \"product\"—but for the \"product-service package\" (part of PSS) which has been sold to the customer. This servicized purchase extends the buying transaction from a one-time sale (product acquisition), to a long-term service relationship (such as in the case of a long-term maintenance-free service contract).\nAnother type of servicizing may be a strategy for providing access to services for people who cannot afford to buy products outright. For example, in the case where auto ownership is economically unfeasible, creative servicizing offers at least three possible solutions: one in which transportation can be achieved \"simultaneously\" (as in car-pooling); one in which transportation can be achieved \"sequentially\" (as in car-sharing); and one in which transportation can be achieved \"eventually\" (rent-to-own).\nTypes.\nThere are various issues in the nomenclature of the discussion of PSS, not least that services are products, and need material products in order to support delivery, however, it has been a major focus of research for several years. The research has focussed on a PSS as system comprising tangibles (the products) and intangibles (the services) in combination for fulfilling specific customer needs. The research has shown that manufacturing firms are more amenable to producing \"results\", rather than solely products as specific artefacts, and that consumers are more amenable to consuming such results. This research has identified three classes of PSS:\nThis typology has been criticized for failing to capture the complexity of PSS examples found in practice. Aas et al. for example proposed a typology with eight categories relevant in the digital era, whereas Van Ostaeyen et al. proposed an alternative that categorizes PSS types according to two distinguishing features: the performance orientation of the dominant revenue mechanism and the degree of integration between product and service elements. According to the first distinguishing feature, a PSS can be designated as \"input-based (IB)\", \"availability-based (AB)\", \"usage-based (UB)\" or \"performance-based (PB)\". The performance-based type can be further subdivided into three subtypes:\nAccording to the second distinguishing feature, a PSS can be designated as segregated, semi-integrated, and integrated, depending on to what extent the product and service elements (e.g. maintenance service, spare parts) are combined into a single offering.\nExamples.\nThe following existing offerings illustrate the PSS concept:\nCase study.\nIn the framework of the European research program of TURAS (Transitioning towards urban resilience and sustainability), a study, in Belgium, explored new hybrid-combinations between products and services systems in order to develop new creative and sustainable business opportunities (both economically viable and creating new jobs) for the Brussels-Capital Region.\nFive workshops have been organized on the following topics:\nAfter 5 co-creation workshops, with more than 50 different stakeholders, and the use of specifics tools, 17 PSS inspiring and promising ideas were identified. After a selection process 4 were chosen for further development of their business models through a series of tools (debugging, light experimentation, simulation, etc.). The study led to the development of a practical toolkit (freely downloadable): PSS Toolkit – Development of innovative business models for product-service systems in an urban context of sustainable transition.\nImpact.\nSeveral authors assert that product service systems will improve eco-efficiency by what is termed \"factor 4\", i.e. an improvement by a factor of 4 times or more, by enabling new and radical ways of transforming what they call the \"product-service mix\" that satisfy consumer demands while also improving the effects upon the environment.\nvan Halen et al. state that the knowledge of PSS enables both governments to formulate policy with respect to sustainable production and consumption patterns, and companies to discover directions for business growth, innovation, diversification, and renewal.\nTietze and Hansen discuss the impact of PSS on firms' innovation behavior identifying three determinants. First, product ownership is not transferred to the customers, but remains with the PSS operating firm. Second, the purpose of a product is different if it is used within PSS solutions than compared to the purpose of products in classical transaction based business models. When offering PSS, products are used as a means for offering a service. Third, the profit function of PSS operating firms differs substantially from profit functions of firms that develop, manufacture and sell their products.\nFrom a manufacturer's perspective, the business potential of a PSS is determined by an interplay of four mechanisms: cost reduction, increased customer value, changes to the company's competitive environment and an expansion of the customer base.", "Engineering,_Manufacturing": 0.9810808301, "qwen": "Yes"}
{"id": "14548752", "revid": "43068821", "url": "https://en.wikipedia.org/wiki?curid=14548752", "title": "EPLaR", "text": "Electronics on Plastic by Laser Release (EPLaR) is a method for manufacturing flexible electrophoretic displays using conventional AM-LCD manufacturing equipment, avoiding the need to build new factories. The technology can also be used to manufacture flexible OLED displays using standard OLED fabrication facilities.\nThe technology was developed by Philips Research and uses standard display glass as used in TFT-LCD processing plants. It is coated with a layer of polyimide using a standard spin-coating procedure used in the production of AM-LCD displays. This polyimide coating can now have a regular TFT matrix formed on top of it in a standard TFT processing plant to form the plastic display, which can then be removed using a laser to finish the display and the glass reused, thus lowering the total cost of manufacture.\nThe EPLaR process is licensed by Philips for use by Taiwan's Prime View International in its TFT manufacturing plants for manufacture of flexible plastic displays.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "35162678", "revid": "3006008", "url": "https://en.wikipedia.org/wiki?curid=35162678", "title": "Aeolus (motorcycle 1903–1905)", "text": "The Aeolus was manufactured in England by the Bown Manufacturing Company between 1903 and 1905, and featured a 492cc single-cylinder engine with shaft drive to the rear wheel. Production was on a limited scale.", "Engineering,_Manufacturing": 0.9996700287, "qwen": "Yes"}
{"id": "35162697", "revid": "1305296", "url": "https://en.wikipedia.org/wiki?curid=35162697", "title": "Aeolus (motorcycle 1914–1916)", "text": "The Aeolus was manufactured between 1914 and 1916 with a 147cc two-stroke engine by the Bown Manufacturing Company, between 1919 and 1924 the machine was branded as Bownian", "Engineering,_Manufacturing": 0.9997757077, "qwen": "Yes"}
{"id": "35194697", "revid": "5288432", "url": "https://en.wikipedia.org/wiki?curid=35194697", "title": "Sculpteo", "text": "Sculpteo is a French company specialized in 3D printing in the cloud. Sculpteo offers an online 3D printing service, for rapid prototyping and production using technologies such as laser sintering, stereo lithography, Multi Jet Fusion, FDM, Polyjet, DLS, DLP/LCD, SLM/DMLS or Binder Jetting. The company was founded in June 2009 by Eric Carreel (co-founder of Inventel, acquired by Technicolor in 2005, and Withings), Clement Moreau and Jacques Lewiner. Sculpteo offers online 3D printing services, particularly in Europe and North America The company was acquired in 2019 by the German multinational chemical company BASF.\nPurpose.\nThe company markets an online 3D printing service and the manufacture of objects from 3D files for individuals, businesses and manufacturers. The customer can upload his 3D model to the site and get his quote automatically.\nThe parts are then manufactured in Sculpteo's ISO 9001-certified factories.\nSculpteo offers a rapid prototyping service, manufacturing on demand, or contract manufacturing, thanks to various manufacturing technologies such as: selective laser sintering, HP Multi Jet Fusion, stereolithography, FDM, etc. These prototyping and production services are aimed at all industries, including the drone, medical, electronics, robotics and luxury sectors.\nThe price depends on the order, the price is calculated according to the volume of material used, the size and the number of pieces.\nHistory and background.\nThe company was created in June 2009. Two years after, in January 2011, \"Sculpteo\" launches their online 3D printing service for the general public by allowing users to make your own avatar from simple 2D photos modeled in 3D. In March 2011, the company launches \"Pro.Sculpteo\", an online 3D printing service for professionals. In June 2011, Sculpteo and 3DVIA announce a direct printing service provided by \"Sculpteo\" via the 3Dvia portal.\nIn January 2012, \"Sculpteo\" launches the 3D printing Cloud Engine and the Sculpteo app at the Consumer Electronics Show in Las Vegas. The app transforms human data into a 3D printed object using an iOS device. In September 2012, \"Sculpteo\" launches \"3DPCase\", the first smartphone app able to generate the 3D file of an iPhone case directly from the smartphone. For the app, \"Sculpteo\" is granted the Prize of Best Innovator at CES 2013. This new approach of unit production highlights the flexibility of the online 3D manufacturing process and allows the company to commercialize iPhone 5 cases before the launch of the iPhone 5.\nIn December 2012, Sculpteo raises 2 million euros thanks to XAnge\",\" branch of the French bank Banque Postale, business angels and founders.\nIn March 2013, \"Sculpteo\" commercializes Lighting plug connectors manufactured in 3D printing. Late 2013, La Poste launches a 3D printing service in post offices, in partnership with Sculpteo.\nIn January 2014, at the Las Vegas Consumer Electronics Show, \"Sculpteo\" unveils \"3D Batch Control\", a cloud 3D printing service designed for professionals and businesses in need of short-run manufacturing. It allows users to upload a 3D file, change the size and dimensions of the object directly within the browser, select a printing material and order their design to be 3D printed and shipped. In May 2014, Sculpteo seeks to reduce 3D printing costs and material squandering by optimizing the quantity of used material. In this light, the company launches a free service named \"Hollowing\". The same month, designers conceive innovative 3D objects that Amazon, in partnership with \"Sculpteo\", proposes in a dedicated online store opened in July 2014. In June 2014, the company continues its pursuit in democratizing 3D technology and integrates its printing service in the Adobe Photoshop Creative Cloud thus rendering the process of 3D manufacture more simple. In November 2014, \"Sculpteo\" launches a free service named \"Thickening\" aimed to reinforce the robustness of fragile parts without having to use a modelling software.\nIn January 2015, at Consumer Electronics Show, \"Sculpteo\" reveals FinalProof, a tool that allows users to apprehend the final result of the object file before printing. In April of the same year, \"Sculpteo\" announces a 5 million euros fundraising thanks to Creadev, investment fund of Mulliez family, and Xange, well known investor. In November, the computer Sprout by HP integrates the 3D printing service of Sculpteo.\nIn January 2016, \"Sculpteo\" launches a new material for additive manufacturing that is more flexible than the others TPU. Several branches are targeted, such as medical branch and the fashion industry. In March, a partnership with Carbon allows \"Sculpteo\" to offer the 3D printing technology \"CLIP\".\nIn November 2019, \"Sculpteo\" was acquired by BASF. The international group said to have purchased the company to market new industrial 3D printing materials more quickly for its 3D printing subsidiary. In June 2022, \"Sculpteo\" announced Alexandre d’Orsetti as its new CEO. ", "Engineering,_Manufacturing": 0.9922327399, "qwen": "Yes"}
{"id": "35209311", "revid": "42677165", "url": "https://en.wikipedia.org/wiki?curid=35209311", "title": "Machine tool builder", "text": "A machine tool builder is a corporation or person that builds machine tools, usually for sale to manufacturers, who use them to manufacture products. A machine tool builder runs a machine factory, which is part of the machine industry.\nThe machine tools often make interchangeable parts, which are assembled into subassemblies or finished assemblies, ending up sold to consumers, either directly or through other businesses at intermediate links of a value-adding chain. Alternatively, the machine tools may help make molds or dies, which then make the parts for the assemblies.\nOverview.\nThe term \"machine tool builder\" implies a company that builds machine tools for sale to other companies, who then use them to manufacture subsequent products. Macroeconomically, machine tools are only means to ends (with the ends being the manufactured products); they are not the ends themselves. Thus it is in the nature of machine tools that there is a spectrum of relationships between their builders, their users, and the end users of the products that they make.\nThere is always natural potential for the machine tool users to be the same people as the builders, or to be different people who occupy an intermediate position in the value stream. Markets often have some proclivity for circumventing such a position, although the proclivity is often not absolute. Every variant on the spectrum of relationships has found some instances of empirical embodiment; and over the centuries, trends can be seen for which variants predominated in each era, as described below.\nMachine tool builders tend not to be in the business of using the machine tools to manufacture the subsequent products (although exceptions, \nincluding chaebol and keiretsu, do exist); and product manufacturers tend not to be in the business of building machine tools. In fact, many machine tool builders are not even in the business of building the control system (typically CNC) that animates the machine; and makers of controls tend not to be in the machine building business (or to inhabit only specialized niches within it).\nFor example, FANUC and Siemens make controls that are sold to many machine tool builders. Each segment tends to find that crossing into other segments involves becoming a conglomerate of dissimilar businesses, which is an execution headache that they don't need as long as focusing on a narrower field is often more profitable in net effect anyway. This trend can be compared to the trend in which companies choose not to compete against their own distributors. Thus a software company may have an online store, but that store does not undercut the distributors' stores on price.\nHistory.\nThe machine tool industry began gradually in the early nineteenth century with individual toolmakers who innovated in machine tool design and building. The ones that history remembers best include Henry Maudslay, Joseph Whitworth, Joseph Clement, James Nasmyth, Matthew Murray, Elisha K. Root, Frederick W. Howe, Stephen Fitch, J.D. Alvord, Frederick W. Howe, Richard S. Lawrence, Henry D. Stone, Christopher M. Spencer, Amos Whitney, and Francis A. Pratt.\nThe industry then grew into the earliest corporate builders such as Brown & Sharpe, the Warner & Swasey Company, and the original Pratt & Whitney company. In all of these cases, there were product manufacturers who started building machine tools to suit their own inhouse needs, and eventually found that machine tools had become product lines in their own right. (In cases such as B&S and P&W, they became the main or sole product lines.)\nIn contrast, Colt and Ford are good examples of product manufacturers that made significant advances in machine tool building while serving their own inhouse needs, but never became \"machine tool builders\" in the sense of having machine tools become the products that they sold. National-Acme was an example of a manufacturer and a machine tool builder merging into one company and selling both the machines and the products that they made (screw machines and fasteners). Hyundai and Mitsubishi are chaebol and keiretsu conglomerates (respectively), and their interests cover from ore mine to end user (in actuality if not always nominally).\nUntil the 1970s, machine tool builder corporations could generally be said to have nationality, and thus it made sense to talk about an American machine tool builder, a German one, or a Japanese one. Since the 1970s, the industry has globalized to the point that assigning nationality to the corporations becomes progressively more meaningless as one travels down the timeline leading up to the present day; currently, most machine tool builders are (or are subsidiaries of) multinational corporations or conglomerates. With these companies it is enough to say \"multinational corporation based in country X\", \"multinational corporation founded in country X\", etc. Subcategories such as \"American machine tool builders\" or \"Japanese machine tool builders\" would be senseless because, for example, companies like Hardinge and Yamazaki Mazak today have significant operations in many countries.\nTrade associations.\nMachine tool builders have long had trade associations, which have helped with such tasks as establishing industry standards, lobbying (of legislatures and, more often, import-and-export-regulating agencies), and training programs. For example, the National Machine Tool Builders' Association (NMTBA) was the trade association of U.S. machine tool builders for many decades, and it helped establish standards such as the NMTB machine taper series (which made toolholders interchangeable between the different brands of machine on a typical machine shop floor). It has since been merged into the Association for Manufacturing Technology (AMT). Other examples have included CECIMO (European Machine Tool Industry Association), the UK's ABMTM, MTTA, and MTA, and the Japan Machine Tool Builders' Association (JMTBA).\nJust as machine tool builders have long had trade associations, so have machine tool distributors (dealers). Examples have been the American Machine Tool Distributors’ Association (AMTDA) and the Japan Machine Tool Trade Association (JMTTA). In recent decades the builders' and distributors' associations have cooperated on shared interests to the extent that some of them have merged. For example, the former NMTBA and AMTDA have merged into the AMT.\nTrade shows.\nMajor trade shows of the industry include IMTS (International Manufacturing Technology Show, formerly called the International Machine Tool Show) and EMO (French \"Exposition Mondiale de la Machine Outil\", English \"Machine Tool World Exposition\"). There are also many smaller trade shows concentrating on specific geographical regions (for example, the Western US, the mid-Atlantic US, the Ruhr Valley, or the Tokyo region) or on specific industries (such as shows tailored especially to the moldmaking industry).\nHistorical studies of machine tool building.\nIn the early 20th century, Joseph Wickham Roe wrote a seminal classic of machine tool history, \"English and American Tool Builders\" (1916), which is extensively cited by later works. About 20 years later Roe published a biography of James Hartness (1937) that also contains some general history of the industry. In 1947, Fred H. Colvin published a memoir, \"Sixty Years with Men and Machines\", that contains quite a bit of general history of the industry. \nL. T. C. Rolt's 1965 monograph, \"A Short History of Machine Tools\", is a widely read classic, as are the series of monographs that Robert S. Woodbury published during the 1960s, which were collected into a volume in 1972 as \"Studies in the History of Machine Tools\".\nIn 1970, Wayne R. Moore wrote about the Moore family firm, the Moore Special Tool Company, who independently invented the jig borer (contemporaneously with its Swiss invention). Moore's monograph, \"Foundations of Mechanical Accuracy\", is a seminal classic of the principles of machine tool design and construction that yield the highest possible accuracy and precision in machine tools (second only to that of metrological machines). The Moore firm epitomized the art and science of the tool and die maker.\nDavid F. Noble's \"Forces of Production\" (1984) is one of the most detailed histories of the machine tool industry from World War II through the early 1980s, relayed in the context of the social impact of evolving automation via NC and CNC. Also in 1984, David A. Hounshell published \"From the American System to Mass Production\", one of the most detailed histories of the machine tool industry from the late 18th century through 1932. It does not concentrate on listing firm names and sales statistics (which Floud's 1976 monograph focuses on) but rather is extremely detailed in exploring the development and spread of practicable interchangeability, and the thinking behind the intermediate steps. It is extensively cited by later works.\nIn 1989, Holland published a history, \"When the Machine Stopped\", that is most specifically about Burgmaster (which specialized in turret drills); but in telling Burgmaster's story, and that of its acquirer Houdaille, Holland provides a history of the machine tool industry in general between World War II and the 1980s that ranks with Noble's coverage of the same era (Noble 1984) as a seminal history. It was later republished under the title \"From Industry to Alchemy\".", "Engineering,_Manufacturing": 0.9999426603, "qwen": "Yes"}
{"id": "61583836", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=61583836", "title": "Learning Factory", "text": "Learning factories represent a realistic manufacturing environment for education, training, and research. In the last decades, numerous learning factories have been built in academia and industry.\nDefinition.\nThe term learning factory consists of two words. The word ‘learning’ indicates the development of competencies, while the word ‘factory’ defines a realistic manufacturing environment. The generally accepted definition was agreed within the CIRP CWG and published in the CIRP Encyclopedia: According to the International Academy for Production Engineering (CIRP) a learning factory is defined by\nDepending on the purpose of the learning factory, learning takes place through teaching, training and/or research. Consequently, learning outcomes may be competency development and/or innovation. An operating model ensuring the sustained operation of the learning factory is desirable.\nThe difference between learning factories and model factories is that learning factories provide a didactical concept and an operating model for training.\nHistory.\nThe term ‘learning factory’ was first coined in the US in 1994, when the National Science Foundation (NSF) awarded a consortium of the Penn State University. Industry-related design projects have been supported on a 2000 m² facility with machines, tools, and materials. Real problems of the industry could be solved in a realistic environment. In 2006, the program received the National Academy of Engineering’s Gordon Prize for Innovation in Engineering Education. In Europe, more and more learning factories have been designed in the last decade. One of the first learning factories in this wave is the ‘Center for industrial Productivity’ founded by the Institute for Production Management, Technology and Machine Tools (Technische Universität Darmstadt), established in 2007 (see section 3). In 2011, the Initiative on ‘European Learning Factories’ was established with the 1st Conference on Learning Factories in Darmstadt (Germany). The Initiative has led to a European collaboration on the topic of learning factories. In 2017, the initiative decided to include learning factories from all continents and renamed itself to the ‘International Association of Learning Factories’.\nExamples of existing learning factories.\nLearning factories in academia.\nTU Darmstadt: Process Learning Factory CiP.\nIn the Process Learning Factory CiP of the Technische Universität Darmstadt focuses on developing competencies for lean production and Industrie 4.0. It has been established in 2007. The delivery of raw material, machining, quality control, assembly, packing, and indirect processes are simulated similar to a small and medium-sized enterprise . Besides the eight variants of the pneumatic cylinder, customer-individualized requirements of different measurements are implemented in a lean machining area. On about 500 m², learners apply lean methods and solve problems on own experience. The learning factory can map different scenarios from a wasteful and unbalanced production environment to a lean and a digital lean state. The 15 different learning modules are structured in lean basics, lean core elements and lean thinking. Within a learning module, practical experiences alternate with theoretical teaching. The Process Learning Factory CiP is a part of the SME competency center for the Rhine-Main area funded by the German Federal Ministry for Economic Affairs and Energy. With new implemented Industrie 4.0-technologies the concept of lean is extended. Different technologies are implemented, e.g. product traceability, worker assistance, digital shopfloor management, predictive maintenance, milk run 4.0 and AGVs. With each implemented technology new topics for the learning modules are integrated. Furthermore, the operating institute has established many learning factories for academia and industry worldwide.\nTechnische Universität Wien: Pilot Factory.\nIn the TU Wien Pilot Factory focuses on Industrie 4.0. It is a realistic test environment with real machines, real production chains, and a real product. On 900 m² a 3D printer is produced that uses the principle of fused deposition modeling. The printer dimensions can be configured on customer requirements. Different Industrie 4.0-concepts are integrated, e.g. process and layout adaptivity, a high degree of human-machine interaction, and use of data analytics for transparency and optimization. AGV transportation connects the manufacturing with the assembly area. The material is replenished automatically. Furthermore, operators are assisted with collaborative robots, assistance systems, sensor technology, and image processing.\nStellenbosch University: Stellenbosch Learning Factory.\nThe Stellenbosch Learning Factory of the Stellenbosch University provides trainings for lean operations, ergonomics and is a research platform for Industrie 4.0. The target groups are industry partners and students for industrial engineering. New developments include a double degree M.Sc. Program with the Reutlingen University. German students have the possibility to visit a summer school. In the learning factory a RFID track and trace-system and a real time KPI visualization are integrated. The product of the Stellenbosch University is a O-scale train set.\nUniversity of Windsor: iFactory.\nThe iFactory of the University of Windsor has the main topics integrated product – systems learning and Industrie 4.0. Desksets and automobile belt tensioners are assembled on 200 sqm. The tracking of processes and production operations planning and scheduling is possible with RFID tags. The complete system is modular and reconfigurable with equipment from FESTO Didactic. The main purpose of the learning factory is research, teaching and demonstration for students and industry. The learning factory was set up in 2011 and is the first of its kind in North America.\nUniversité du Luxembourg: Operational Excellence Laboratory.\nThe Operational Excellence Laboratory of the Université du Luxembourg is place for industrial partners to get hands-on experience of lean tools and demonstrate new technology related to Industrie 4.0. Examples for new technologies are the integration of RFID, augmented reality and digital manuals. Furthermore engineering master students are trained. The learning factory is a platform for retrofitting new technological features to develop, analyze and validate their usability in assembly or disasssembly lines. The product of the learning factory is a hole puncher.\nTechnische Universität München: Learning Factory for Lean Production (LSP).\nThe focus of the Learning Factory for Lean production (LSP) at the TU München is lean production. The manufactured product is a real gearbox with 24 variants. The facility consists of an assembly area, a kaizen workshop area, and a theoretical teaching area. The processes logistics, assembly, quality control and packaging are mapped. A typical lean journey is recreated during the course: from an unsatisfying situation to a lean state. The theory is taught in theory lessons slots. Four to six trainings are offered every year. The mobile equipment can be transported to any location.\nRuhr-Universität Bochum: LPS Learning Factory.\nThe main topics of the LPS Learning Factory are lean production, Industrie 4.0 and resource efficiency. It was established in 2009 by the Ruhr Universität Bochum. Bottle caps, bottle cap holders and various make-to-order products are manufactured on 1800 m². The production environment includes various machine tools, load transports, manual assembly stations, and various industrial robots. The main topics are lean production, Industrie 4.0 and resource efficiency. Every year 900 students are practicing exercises. Real products that are purchased for the industry are produced. Besides that, numerous research projects take place in the learning factory, e.g. Industrie 4.0 maturity model, assistance and learning systems, cyber-physical production systems and industrial robotics. Since 2018 the learning factory is part of the SME 4.0 competence center Siegen.\nHochschule Reutlingen: Werk150.\nThe Werk150 (formerly ESB Logistics Learning Factory) at ESB Business School is an authentic learning, development and research environment. The facility, which was started in 2014, provides a cutting-edge infrastructure for the training and advanced training of students. Moreover, topical issues of applied research are also addressed, and new methods, tools and future technologies as well as control methods for adaptable work and logistics systems are developed and tested. The results of the applied research are continuously integrated in the course activities. The Werk150 images a model production company with its entire industrial value chain and a changing product and services portfolio. Especially processes in the areas of product and work system engineering, incoming goods, storage, order picking, production, assembly and additive manufacturing as well as distribution are replicated and looked at in their entirety.\nIn the Werk150 the requirements and influences from Industry 4.0 are investigated and conveyed in teaching and further training courses. It has a digital twin or image that is linked with a real factory using information and communication technologies. Thus, both products and production can be planned and simulated virtually, production controlled digitally and the status and localisation of orders, parts and resources monitored in real time. \nDresden University of Technology: Process-to-Order Lab (P2O-Lab).\nThe P2O-Lab is a 110 m² learning factory on the premises of the Dresden University of Technology. Building on solution approaches from the fields of modularization, digitization and artificial intelligence, the P2O-Lab investigates the next steps to serve highly variable markets with almost binary product life cycles. The P2O Lab asks itself which requirements, models, methods, and tools must be fulfilled for this. As an accompanying UserStory, the goal is to derive, evaluate and implement a suitable process from existing plant modules directly from the product order. The findings from the current research are subsequently flowing into the teaching of the Faculty of Electrical Engineering at the TU Dresden. In addition, students as well as external persons have the opportunity to gain hands-on experience in the P2O-Lab in the context of workshops and internships.\nLearning factories in industry.\nMPS Lernplattform.\nSince 2011, the MPS Lernplattform of the Daimler AG manufactures different products on 3000 m² with the main topic of lean production. The original components of the production as well as 1:10 models with several simulations are used. A press shop, body shop, paint shop, assembly and logistics as parts of the automobile industry are simulated. The assembled products can be reused after the training: e.g. roof control units, sun visors, covers, floor mats or room tears. Qualified in-house employees carry out the training who have didactical background knowledge as well as long-term experience in the production area. The training consists of 20% theory and 80% practice. More than ten different learning modules are offered for participants who take important insights to their daily work. The MPS Lernplattform increasingly relies on cooperation with external partners such as the TU Darmstadt.\nFesto Learning Factory Scharnhausen.\nThe Festo Learning Factory in Scharnhausen is operated by Festo AG since 2014 with four different topics: mechanical processing (1), valve and valve terminal assembly (2), automation and process improvement (4), administration of the learning factory (4). Pneumatic valves and valve terminals are manufactured on 220 m² on four rooms. More than forty learning modules are offered on fourteen different workplaces. The participants are exclusively from Festo, especially for the training of new operators and advanced qualification of incumbent workers. Each team leader or a qualified team specialist trains the operators by themselves. Therefore ‘Train-the-trainer’-modules have been developed. The trainings are developed continuously. New products, new processes, new production equipment are integrated.\nApproach to Competency-Oriented Planning and Design.\nThe concept of learning factories offers potentials to former didactical and technical approaches. Through the realistic environment, learners are more motivated and the development of competencies facilitates. Problem-based, project-based or research-based learning is possible. Action-oriented learning results in significant advantages compared to traditional teaching methods. Methods, innovations, and technologies can be transferred to the industry more easily. Through learning factories learners can apply methods on a realistic production environment without the negative effect of stopping production lines in their own enterprise.\nLearning Factories are designed on three design levels:\nMore details about the design process of learning factories can be seen in the dissertation of Michael Tisch with the title “Modellbasierte Methodik zur kompetenzorientierten Gestaltung von Lernfabriken für die schlanke Produktion”.\nLimitations of learning factories.\nThe learning factory concept is also limited. The planning, development, construction, and operation of learning factories require financial and personnel resources. Physical learning factories need space in a facility. Machines, workplaces, and other factory elements must be purchased and maintained. Partners and personnel should be willing and able to participate in a learning factory. The sustainability must be ensured through an operating model. Furthermore, learning factories map limited sections of production environments. A single learning factory is not able to provide a suitable, general environment for all challenges in academia and industry. Specific industrial sectors, addressed topics, single production processes, company departments, and target groups are addressed. The mapping abilities of learning factories are limited.", "Engineering,_Manufacturing": 1.0000023842, "qwen": "Yes"}
{"id": "61608807", "revid": "14365232", "url": "https://en.wikipedia.org/wiki?curid=61608807", "title": "Savita Oil Technologies Limited", "text": "Savita Oil Technologies Limited  (formerly known as Savita Chemical) is an Indian automotive, industrial lubricant and petroleum specialty oils production company with its headquarters at Mumbai, Maharashtra. It has primarily engaged in manufacturing of petroleum specialties such as transformer oils, liquid paraffin and white oils, petroleum jellies, synthetic petroleum sulfonates and other specialties. Savita Oil has been ranked \"#42\" in Fortune Next 500 list under lube oil and lubricants category, by Fortune India.\nThe company is also involved in manufacturing of automotive and industrial lubricants. In 2018, the company relaunched Savsol, a domestic brand of lubricants and engine oils.\nHistory.\nThe company has been listed on Bombay Stock Exchange and National Stock Exchange since 1994.\nIt operates three manufacturing plants in Western India. Its Lube Oil manufacturing plant situated at Silvassa, is a fully automated manufacturing unit and has been certified for ISO 9001:2015 & ISO 14001:2015.\nPartnership.\nIn 2018, Tata Motors signed an agreement with Savita Oil Technologies to manufacture and provide original oils for their passenger vehicle brands.", "Engineering,_Manufacturing": 0.9996040463, "qwen": "Yes"}
{"id": "60421160", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=60421160", "title": "Athletics at the 1971 Mediterranean Games – Results", "text": "These are the partial results of the athletics competition at the 1971 Mediterranean Games taking place between 12 and 17 October in Izmir, Turkey.\nMen's results.\n100 meters.\nHeats – 12 OctoberWind:\nFinal – 13 OctoberWind: +0.1 m/s\n200 meters.\nHeatsWind:\nFinal – 16 OctoberWind: +0.1 m/s\n400 meters.\nHeats – 13 October\nFinal – 14 October\n800 meters.\nHeats – 15 October\nFinal – 16 October\n1500 meters.\nHeats – 12 October\nFinal – 13 October\n5000 meters.\nHeats – 12 October\nFinal – 14 October\n10,000 meters.\n16 October\nMarathon.\n17 October\n110 meters hurdles.\nHeats – 14 OctoberWind:\nFinal – 15 OctoberWind: +0.3 m/s\n400 meters hurdles.\nHeats – 12 October\nFinal – 13 October\n3000 meters steeplechase.\n16 October\n4 × 100 meters relay.\n15 October\n4 × 400 meters relay.\n16 October\n20 kilometers walk.\n12 October\n50 kilometers walk.\n14 October\nHigh jump.\n16 October\nPole vault.\n15 October\nLong jump.\n13 October\nTriple jump.\n15 October\nShot put.\n12 October\nDiscus throw.\n14 October\nHammer throw.\n15 October\nJavelin throw.\n16 October\nDecathlon.\n13–14 October\nWomen's results.\n100 meters.\nHeats – 12 October\nFinal – 13 October\n400 meters.\n16 October\n800 meters.\n14 October\n1500 meters.\n15 October\n100 meters hurdles.\nHeats – 13 October\nFinal – 14 October\n4 × 100 meters relay.\n15 October\nHigh jump.\n15 October\nDiscus throw.\n12 October", "Engineering,_Manufacturing": 1.000002265, "qwen": "Yes"}
{"id": "60444376", "revid": "7282353", "url": "https://en.wikipedia.org/wiki?curid=60444376", "title": "Ensinger (company)", "text": "The Ensinger Group is engaged in the development and manufacture of compounds, semi-finished products, technical parts, composite materials and profiles made of engineering and high-performance plastics. The family-owned enterprise is represented in major industrial regions with manufacturing facilities or sales offices. The main office is located in Nufringen/Baden-Württemberg, Germany.\nHistory.\nThe company was founded in 1966 by Wilfried Ensinger. First areas of focus included the manufacture and sale of thermoplastic engineering plastics. Closely linked with this technology, the company worked on further development of the extrusion process and application technology. A short time after relocation of the headquarters to Nufringen, Ensinger launched the production of components manufactured by machining semi-finished products. In 1977, the company dispatched its first volume-produced thermal insulating profiles made of glass fibre-reinforced polyamide 6.6 to manufacturers of aluminium windows. A second plant was erected in 1980 in Cham/Bavaria. After the launch of other product lines, Ensinger founded a number of additional subsidiaries in Europe, North America, South America and Asia. Since 2007 the company has been present in China with its own production facility.\nBusiness field.\nThe products are used in a wide variety of industrial sectors, including mechanical engineering, in the automotive and aviation industry and in medical technology. The technical solutions based on thermoplastic polymers are also very common in the food industry and in electrical and semiconductor technology. In many cases, high -performance plastics replace other materials such as metals or ceramics. The segment disc distance made of insulating plastic for insulating glass was sold to the Fenzi Group in 2019.\nLocations.\nThe company group employs a total workforce of ca. 2,700 in 33 locations.\nProduction sites.\nThe company also owns subsidiaries in Denmark, Poland, Sweden, Spain, Czech Republic, Turkey, Japan, Singapore, Vietnam, India, Taiwan and South Korea.\nBusiness segments.\nTo process the thermoplastic polymers, Ensinger uses a number of production methods, in particular compounding, extrusion, machining, injection moulding, casting, sintering and compression molding. \nThe spectrum of materials used ranges from engineering plastics (such as PA, PET and POM) through to the category of highly temperature-resistant high-performance plastics (such as PEEK, PPS, and PI).\nThermoplastic polymer products are used in different fields, including the automotive and aerospace industries, mechanical engineering, medical technology, the electrical and semiconductor sectors and food industry. \nOn 1 February 2022, it was announced Ensinger had concluded a joint agreement to acquire INEOS Styrolution's \"StyLight\" thermoplastic composite materials business. ", "Engineering,_Manufacturing": 1.0000066757, "qwen": "Yes"}
{"id": "9613795", "revid": "983429567", "url": "https://en.wikipedia.org/wiki?curid=9613795", "title": "Design to standards", "text": "\"Design to Standards\" means to design items with generally accepted and uniform procedures, dimensions or materials.\nBenefits.\nProduct standardization is a technique in engineering design that aim to reduce the number of different parts within a product. The benefits are:\nThe supply chain costs are simple to reason:\nProduct platforms are enabled through:\nThe product design process becomes faster because:\nStandards.\nStandardization can occur through two ways", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "66501526", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=66501526", "title": "Time metrology", "text": "Time metrology or time and frequency metrology is the application of metrology for time keeping, including frequency stability.\nIts main tasks are the realization of the second as the SI unit of measurement for time and the establishment of time standards and frequency standards as well as their dissemination.", "Engineering,_Manufacturing": 1.0, "qwen": "Yes"}
{"id": "3455033", "revid": "33422525", "url": "https://en.wikipedia.org/wiki?curid=3455033", "title": "Moscow Aircraft Production Association", "text": "MAPO - the Moscow Aircraft Production Association  was a major Russian state-owned military aircraft manufacturer.\nHistory.\nMAPO has its origins in Plant #30 of the Dux Factory company. Plant #30 was established in 1939 in Dubna. In December 1941, it was relocated to the former site of Plant #1, where it manufactured the Ilyushin Il-2. In 1950, it merged with Plant #381, to produce the Il-28 in larger volumes. In 1953, Lukhovitsy Machine Building Plant was established as a subsidiary of the plant.\nPlant #30 became known as the \"Znamya Truda Machine-Building Plant\" in 1965, and as the Moscow Aircraft Production Organisation in 1973.\nIn the early 1990s, it employed 30,000 workers. In 1995, MAPO was merged with the Mikoyan Design Bureau, forming MAPO-MiG. In January 1996, a decree of President Boris Yeltsin established MAPO VPK, which combined 12 different aviation companies, including MAPO-MiG, Kamov, Klimov, the Chernyshev Machine Building Enterprise and Aviabank.\nUnlike Sukhoi, which managed to secure export contracts with China and India, MAPO continued to be unprofitable throughout the 1990s. In December 1999, MAPO was renamed Russian Aircraft Corporation MiG.\nIn 2006, MAPO merged with Sukhoi and several other Russian aviation companies to form United Aircraft Corporation. The majority of MAPO's former assets are now part of Mikoyan.\nThe Lukhovitsy and Znamya Truda plants are currently known as 'MiG Manufacturing Complex №1' (ПК №1 PCK «МиГ») and 'MiG Manufacturing Complex №2' (ПК №2 PCK «МиГ»), respectively.\nNames.\nOver the years, it has also been known as OSOAVIAKHIM Plant #1, GAZ No. 1, Menjinski Plant #39, Orjonikidze Plant #381, Plant #30, MMZ (Moscow Machine-Building Plant) \"Znamya Truda\" (Banner of Labor), P.A. Voronin Production Center, and \"Moscow Aircraft Production Organization (MAPO) named after Dementiev\" (, Minister of Aircraft Industry from 1953 to 1977).", "Engineering,_Manufacturing": 0.9999547005, "qwen": "Yes"}
{"id": "26617530", "revid": "10044298", "url": "https://en.wikipedia.org/wiki?curid=26617530", "title": "Roller screw", "text": "A roller screw, also known as a planetary roller screw or satellite roller screw, is a low-friction precision screw-type actuator, a mechanical device for converting rotational motion to linear motion, or vice versa. Planetary roller screws are used as the actuating mechanism in many electro-mechanical linear actuators. Due to its complexity the roller screw is a relatively expensive actuator (as much as an order of magnitude more expensive than ball screws), but may be suitable for high-precision, high-speed, heavy-load, long-life and heavy-use applications.\nRoller screw mechanisms are commonly incorporated into motion/positioning systems in a variety of industries such as manufacturing and aerospace.\nPrinciple of operation.\nA roller screw is a mechanical actuator similar to a ball screw that uses rollers as the load transfer elements between nut and screw instead of balls. The rollers are typically threaded but may also be grooved depending on roller screw type. Providing more bearing points than ball screws within a given volume, roller screws can be more compact for a given load capacity while providing similar efficiency (75%-90%) at low to moderate speeds, and maintain relatively high efficiency at high speeds. Roller screws can surpass ball screws in regard to positioning precision, load rating, rigidity, speed, acceleration, and lifetime. Standard roller screw actuators can achieve dynamic load ratings above 130 tons of force (exceeded in single-unit actuator capacity only by hydraulic cylinders).\nThe three main elements of a typical planetary roller screw are the screw shaft, nut and planetary roller. The screw, a shaft with a multi-start V-shaped thread, provides a helical raceway for multiple rollers radially arrayed around the screw and encapsulated by a threaded nut. The thread of the screw is typically identical to the internal thread of the nut. The rollers spin in contact with, and serve as low-friction transmission elements between screw and nut. The rollers typically have a single-start thread with convex flanks that limit friction at the rollers' contacts with screw and nut. The rollers typically orbit the screw as they spin (in the manner of planet gears to sun gear), and are thus known as planetary, or satellite, rollers. As with a lead screw or ball screw, rotation of the nut results in screw travel, and rotation of the screw results in nut travel.\nFor a given screw diameter and quantity of thread starts more rollers corresponds to higher static load capacity, but not necessarily to a higher dynamic load capacity. Preloaded split nuts and double nuts are available to eliminate backlash.\nPlanetary roller screw types.\nCarl Bruno Strandgren developed some of the earliest effective forms of roller screws and applied for a patent in Nice, France in February 1942. The French patent #888.281 was granted in August 1943 and published in December of the same year. The first commercial Roller Screw was designed and manufactured under his supervision in 1949 and was mounted on a narrow gauge locomotive which operated in a northern France coal mine. Subsequent units were produced and mounted on machine-tools and starting in 1955 on aircraft. At that time Carl Bruno Strandgren applied for a new patent incorporating detailed calculations and detailed manufacturing considerations for which he was awarded US patents for such a “Screw-Threaded Mechanism” in 1954, and “Nut and Screw Devices” and the \"Roller Screw\" in 1965.\nRoller screw types are defined by the motion of the rollers relative to the nut and screw. The four commercially available types of roller screw are \"standard\", \"inverted\", \"recirculating\", and \"bearing ring\".\n\"Differential roller screws\", typically variants of the standard and recirculating types, are also commercially available. Differential roller screws modify the rotational speed ratios between the rollers and the screw by varying the flank angles and contact points of the threads or grooves. In that way differential roller screws change the effective lead of the screw. William J. Roantree received a US patent for the \"Differential Roller Nut\" in 1968.\nStandard planetary roller screw.\nThe standard planetary roller screw is also known as the non-recirculating roller screw. The lack of axial movement of the roller relative to the nut, and the gearing of rollers to nut, are definitive of the standard type of roller screw.\nThe nut and screw have identical multiple-start threads. The rollers have a single-start thread with an angle matching the nut thread. The matched thread angle prevents axial movement between the nut and the roller as the rollers spin. The nut assembly includes spacer rings and ring gears that position and guide the rollers. The spacer rings, which rotate within the ring gears, have equidistant holes that act as rotary bearings for the smooth pivot ends (studs) of the rollers. The ring gears time the spinning and orbit of the rollers about the screw axis by engaging gear teeth near the ends of the rollers. The spacer rings rotate on axis with the screw in unison with the orbit of the rollers. The spacer rings float relative to the nut, axially secured by retaining rings, because they spin around the screw at a lower frequency (angular velocity) than the nut.\nConfiguration.\nStandard roller screws are typically identified by screw diameter (typically ranging from 3.5mm – 200mm) and lead (1mm – 62mm). The threading of the screw (3 – 6 starts) is either rolled (lower capacity) or ground (higher capacity). The diameters of the nut and rollers (7 – 14 in quantity) are simple functions of the screw diameter and lead.\nWhere:\nThe following relationships apply to standard and inverted roller screws:\nFor example, if \nthen\nInverted roller screw.\nThe inverted planetary roller screw is also known as the reverse roller screw. The lack of axial movement of the roller relative to the screw, and the gearing of rollers to screw, are definitive of the inverted type of planetary roller screw. This type of roller screw was developed simultaneously with the standard roller screw.\nInverted roller screws operate on the same principles of standard roller screws except that the function of the nut and screw is reversed in relation to the rollers. The rollers move axially within the nut, which is elongated to accommodate the full extent of screw shaft travel. The threaded portion of the screw shaft is limited to the threaded length of the rollers. The non-threaded portion of the screw shaft can be a smooth or non-cylindrical shape. The ring gear is replaced by gear teeth above and below the threaded portion of the screw shaft.\nAside from the inversion of the relationship of rollers to nut and screw, the configuration and relationships of inverted roller screws match those of standard roller screws.\nRecirculating roller screw.\nThe recirculating type of planetary roller screw is also known as a recycling roller screw. A recirculating roller screw can provide a very high degree of positional accuracy by using minimal thread leads. The rollers of a recirculating roller screw move axially within the nut until being reset after one orbit about the screw. Recirculating roller screws do not employ ring gears. Carl Bruno Strandgren was awarded a US Patent for the recirculating roller screw in 1965.\nThe screw and nut may have very fine identical single- or two-start threads. Recirculating rollers are grooved (instead of threaded) so they move axially during spinning engagement with the threads of the nut and screw, shifting up or down by one lead of thread after completing an orbit around the screw. The nut assembly typically includes a slotted cage and cam rings. The cage captivates the rollers in elongated slots, equally spacing the rollers while permitting rotation and axial motion of the rollers. The cam rings have opposing cams aligned with an axial groove in the wall of the nut. After a roller completes an orbit about the nut it is released into the groove, disengages from nut and screw, and is pushed between the cams to the axial midpoint of the nut assembly (shifting by a distance equal to the lead of the screw). Returned to its starting position, and reengaged to nut and screw, the roller may then orbit the screw once again.\nIn 2006, Charles C. Cornelius and Shawn P. Lawlor received a patent for a cage-less recirculating roller screw system. As with the traditional recirculating roller screw system, rollers disengage from the screw when they come upon an axial groove in the wall of the nut. The system differs in that the rollers are continually engaged by the nut, and the axial groove of the nut is threaded. Non-helical threads in the axial groove of the nut return the roller to its axial starting position (after completion of an orbit). Non-circular compression rings, or cam rings, at opposite ends of the rollers (roller axles) apply constant pressure between rollers and nut, synchronizing roller rotation and thrusting the rollers into the nut's axial groove. Lacking ring gears and roller cage, cage-less recirculating roller screws can be relatively efficient and, as a result, permit higher dynamic capacities for some screw shaft diameters.\nBearing ring roller screw.\nIn 1986 Oliver Saari was awarded a patent for a bearing ring roller screw, commonly referred to by its trademark, Spiracon. This type matches the orbit of the rollers to the rotation of the nut assembly. The actuator contains more load transfer elements than the other types, a bearing ring and thrust bearings, but manufacture of component parts is relatively simple (e.g. gearing teeth may be eliminated).\nIn the other roller screw types above, loads are transferred from the nut through the rollers to the screw (or in the reverse order). In this type of actuator, thrust bearings and a freely rotating internally grooved bearing ring transfer loads between the rollers and the nut.\nThe screw has a multi-start thread. The rollers and encapsulating rotating ring are identically grooved, not threaded, so there is no axial movement between the two. The nut assembly includes a cylindrical housing capped by non-rotating spacer rings. The spacer rings have equidistant holes that act as rotary bearings for the smooth pivot ends (studs) of the rollers. Roller-type thrust bearings between the spacer rings and bearing ring permit free rotation of the bearing ring while transferring the axial load between the two.\nThe rollers act as the “threads” of the nut assembly, causing axial movement of the rotating screw due to their orbital restraint. Screw rotation spins the rollers, which spin the bearing ring, dissipating the load-induced friction along the way.\nTimothy A. Erhart was awarded a US patent in 1996 for a linear actuator effectively incorporating an inverted bearing ring roller screw. The screw shaft is grooved the length of and to match the grooved rollers, which travel with the shaft. The bearing ring is elongated and internally threaded for the length of screw shaft travel. The nut assembly housing and sealed end ring forms the exterior of the actuator assembly.", "Engineering,_Manufacturing": 1.0000027418, "qwen": "Yes"}
{"id": "26626178", "revid": "38783874", "url": "https://en.wikipedia.org/wiki?curid=26626178", "title": "Failure of electronic components", "text": "Electronic components have a wide range of failure modes. These can be classified in various ways, such as by time or cause. Failures can be caused by excess temperature, excess current or voltage, ionizing radiation, mechanical shock, stress or impact, and many other causes. In semiconductor devices, problems in the device package may cause failures due to contamination, mechanical stress of the device, or open or short circuits.\nFailures most commonly occur near the beginning and near the ending of the lifetime of the parts, resulting in the bathtub curve graph of failure rates. Burn-in procedures are used to detect early failures. In semiconductor devices, parasitic structures, irrelevant for normal operation, become important in the context of failures; they can be both a source and protection against failure.\nApplications such as aerospace systems, life support systems, telecommunications, railway signals, and computers use great numbers of individual electronic components. Analysis of the statistical properties of failures can give guidance in designs to establish a given level of reliability. For example, power-handling ability of a resistor may be greatly derated when applied in high-altitude aircraft to obtain adequate service life.\nA sudden fail-open fault can cause multiple secondary failures if it is fast and the circuit contains an inductance; this causes large voltage spikes, which may exceed 500 volts. A broken metallisation on a chip may thus cause secondary overvoltage damage. Thermal runaway can cause sudden failures including melting, fire or explosions.\nPackaging failures.\nThe majority of electronic parts failures are packaging-related. Packaging, as the barrier between electronic parts and the environment, is very susceptible to environmental factors. Thermal expansion produces mechanical stresses that may cause material fatigue, especially when the thermal expansion coefficients of the materials are different. Humidity and aggressive chemicals can cause corrosion of the packaging materials and leads, potentially breaking them and damaging the inside parts, leading to electrical failure. Exceeding the allowed environmental temperature range can cause overstressing of wire bonds, thus tearing the connections loose, cracking the semiconductor dies, or causing packaging cracks. Humidity and subsequent high temperature heating may also cause cracking, as may mechanical damage or shock.\nDuring encapsulation, bonding wires can be severed, shorted, or touch the chip die, usually at the edge. Dies can crack due to mechanical overstress or thermal shock; defects introduced during processing, like scribing, can develop into fractures. Lead frames may contain excessive material or burrs, causing shorts. Ionic contaminants like alkali metals and halogens can migrate from the packaging materials to the semiconductor dies, causing corrosion or parameter deterioration. Glass-metal seals commonly fail by forming radial cracks that originate at the pin-glass interface and permeate outwards; other causes include a weak oxide layer on the interface and poor formation of a glass meniscus around the pin.\nVarious gases may be present in the package cavity, either as impurities trapped during manufacturing, outgassing of the materials used, or chemical reactions, as is when the packaging material gets overheated (the products are often ionic and facilitate corrosion with delayed failure). To detect this, helium is often in the inert atmosphere inside the packaging as a tracer gas to detect leaks during testing. Carbon dioxide and hydrogen may form from organic materials, moisture is outgassed by polymers and amine-cured epoxies outgas ammonia. Formation of cracks and intermetallic growth in die attachments may lead to formation of voids and delamination, impairing heat transfer from the chip die to the substrate and heatsink and causing a thermal failure. As some semiconductors like silicon and gallium arsenide are infrared-transparent, infrared microscopy can check the integrity of die bonding and under-die structures.\nRed phosphorus, used as a charring-promoter flame retardant, facilitates silver migration when present in packaging. It is normally coated with aluminium hydroxide; if the coating is incomplete, the phosphorus particles oxidize to the highly hygroscopic phosphorus pentoxide, which reacts with moisture to phosphoric acid. This is a corrosive electrolyte that in the presence of electric fields facilitates dissolution and migration of silver, short-circuiting adjacent packaging pins, lead frame leads, tie bars, chip mount structures, and chip pads. The silver bridge may be interrupted by thermal expansion of the package; thus, disappearance of the shorting when the chip is heated and its reappearance after cooling is an indication of this problem. Delamination and thermal expansion may move the chip die relative to the packaging, deforming and possibly shorting or cracking the bonding wires.\nContact failures.\nElectrical contacts exhibit ubiquitous contact resistance, the magnitude of which is governed by surface structure and the composition of surface layers. Ideally contact resistance should be low and stable, however weak contact pressure, mechanical vibration, corrosion, and the formation of passivizing oxide layers and contacts can alter contact resistance significantly, leading to resistance heating and circuit failure.\nSoldered joints can fail in many ways like electromigration and formation of brittle intermetallic layers. Some failures show only at extreme joint temperatures, hindering troubleshooting. Thermal expansion mismatch between the printed circuit board material and its packaging strains the part-to-board bonds; while leaded parts can absorb the strain by bending, leadless parts rely on the solder to absorb stresses. Thermal cycling may lead to fatigue cracking of the solder joints, especially with elastic solders; various approaches are used to mitigate such incidents. Loose particles, like bonding wire and weld flash, can form in the device cavity and migrate inside the packaging, causing often intermittent and shock-sensitive shorts. Corrosion may cause buildup of oxides and other nonconductive products on the contact surfaces. When closed, these then show unacceptably high resistance; they may also migrate and cause shorts. Tin whiskers can form on tin-coated metals like the internal side of the packagings; loose whiskers then can cause intermittent short circuits inside the packaging. Cables, in addition to the methods described above, may fail by fraying and fire damage.\nPrinted circuit board failures.\nPrinted circuit boards (PCBs) are vulnerable to environmental influences; for example, the traces are corrosion-prone and may be improperly etched leaving partial shorts, while the vias may be insufficiently plated through or filled with solder. The traces may crack under mechanical loads, often resulting in unreliable PCB operation. Residues of solder flux may facilitate corrosion; those of other materials on PCBs can cause electrical leaks. Polar covalent compounds can attract moisture like antistatic agents, forming a thin layer of conductive moisture between the traces; ionic compounds like chlorides tend to facilitate corrosion. Alkali metal ions may migrate through plastic packaging and influence the functioning of semiconductors. Chlorinated hydrocarbon residues may hydrolyze and release corrosive chlorides; these are problems that occur after years. Polar molecules may dissipate high-frequency energy, causing parasitic dielectric losses.\nAbove the glass transition temperature of PCBs, the resin matrix softens and becomes susceptible contaminant diffusion. For example, polyglycols from the solder flux can enter the board and increase its humidity intake, with corresponding deterioration of dielectric and corrosion properties. Multi-layer substrates using ceramics suffer from many of the same problems.\nConductive anodic filaments (CAFs) may grow within the boards along the fibers of the composite material. Metal is introduced to a vulnerable surface typically from plating the vias, then migrates in presence of ions, moisture, and electrical potential; drilling damage and poor glass-resin bonding promotes such failures. The formation of CAFs usually begins by poor glass-resin bonding; a layer of adsorbed moisture then provides a channel through which ions and corrosion products migrate. In presence of chloride ions, the precipitated material is atacamite; its semiconductive properties lead to increased current leakage, deteriorated dielectric strength, and short circuits between traces. Absorbed glycols from flux residues aggravate the problem. The difference in thermal expansion of the fibers and the matrix weakens the bond when the board is soldered; the lead-free solders which require higher soldering temperatures increase the occurrence of CAFs. Besides this, CAFs depend on absorbed humidity; below a certain threshold, they do not occur. Delamination may occur to separate the board layers, cracking the vias and conductors to introduce pathways for corrosive contaminants and migration of conductive species.\nRelay failures.\nEvery time the contacts of an electromechanical relay or contactor are opened or closed, there is a certain amount of contact wear. An electric arc occurs between the contact points (electrodes) both during the transition from closed to open (break) or from open to closed (make). The arc caused during the contact break (break arc) is akin to arc welding, as the break arc is typically more energetic and more destructive.\nThe heat and current of the electrical arc across the contacts creates specific cone & crater formations from metal migration. In addition to the physical contact damage, there appears also a coating of carbon and other matter. This degradation drastically limits the overall operating life of a relay or contactor to a range of perhaps 100,000 operations, a level representing 1% or less than the mechanical life expectancy of the same device.\nSemiconductor failures.\nMany failures result in generation of hot electrons. These are observable under an optical microscope, as they generate near-infrared photons detectable by a CCD camera. Latchups can be observed this way. If visible, the location of failure may present clues to the nature of the overstress. Liquid crystal coatings can be used for localization of faults: cholesteric liquid crystals are thermochromic and are used for visualisation of locations of heat production on the chips, while nematic liquid crystals respond to voltage and are used for visualising current leaks through oxide defects and of charge states on the chip surface (particularly logical states). Laser marking of plastic-encapsulated packages may damage the chip if glass spheres in the packaging line up and direct the laser to the chip.\nExamples of semiconductor failures relating to semiconductor crystals include:\nParameter failures.\nVias are a common source of unwanted serial resistance on chips; defective vias show unacceptably high resistance and therefore increase propagation delays. As their resistivity drops with increasing temperature, degradation of the maximum operating frequency of the chip the other way is an indicator of such a fault. \"Mousebites\" are regions where metallization has a decreased width; such defects usually do not show during electrical testing but present a major reliability risk. Increased current density in the mousebite can aggravate electromigration problems; a large degree of voiding is needed to create a temperature-sensitive propagation delay.\nSometimes, circuit tolerances can make erratic behaviour difficult to trace; for example, a weak driver transistor, a higher series resistance and the capacitance of the gate of the subsequent transistor may be within tolerance but can significantly increase signal propagation delay. These can manifest only at specific environmental conditions, high clock speeds, low power supply voltages, and sometimes specific circuit signal states; significant variations can occur on a single die. Overstress-induced damage like ohmic shunts or a reduced transistor output current can increase such delays, leading to erratic behavior. As propagation delays depend heavily on supply voltage, tolerance-bound fluctuations of the latter can trigger such behavior.\nGallium arsenide monolithic microwave integrated circuits can have these failures:\nMetallisation failures.\nMetallisation failures are more common and serious causes of FET transistor degradation than material processes; amorphous materials have no grain boundaries, hindering interdiffusion and corrosion. Examples of such failures include:\nElectrical overstress.\nMost stress-related semiconductor failures are electrothermal in nature microscopically; locally increased temperatures can lead to immediate failure by melting or vaporising metallisation layers, melting the semiconductor or by changing structures. Diffusion and electromigration tend to be accelerated by high temperatures, shortening the lifetime of the device; damage to junctions not leading to immediate failure may manifest as altered current–voltage characteristics of the junctions. Electrical overstress failures can be classified as thermally-induced, electromigration-related and electric field-related failures; examples of such failures include:\nElectrostatic discharge.\nElectrostatic discharge (ESD) is a subclass of electrical overstress and may cause immediate device failure, permanent parameter shifts and latent damage causing increased degradation rate. It has at least one of three components, localized heat generation, high current density and high electric field gradient; prolonged presence of currents of several amperes transfer energy to the device structure to cause damage. ESD in real circuits causes a damped wave with rapidly alternating polarity, the junctions stressed in the same manner; it has four basic mechanisms:\nCatastrophic ESD failure modes include:\nA parametric failure only shifts the device parameters and may manifest in stress testing; sometimes, the degree of damage can lower over time. Latent ESD failure modes occur in a delayed fashion and include:\nCatastrophic failures require the highest discharge voltages, are the easiest to test for and are rarest to occur. Parametric failures occur at intermediate discharge voltages and occur more often, with latent failures the most common. For each parametric failure, there are 4–10 latent ones. Modern VLSI circuits are more ESD-sensitive, with smaller features, lower capacitance and higher voltage-to-charge ratio. Silicon deposition of the conductive layers makes them more conductive, reducing the ballast resistance that has a protective role.\nThe gate oxide of some MOSFETs can be damaged by 50 volts of potential, the gate isolated from the junction and potential accumulating on it causing extreme stress on the thin dielectric layer; stressed oxide can shatter and fail immediately. The gate oxide itself does not fail immediately but can be accelerated by stress induced leakage current, the oxide damage leading to a delayed failure after prolonged operation hours; on-chip capacitors using oxide or nitride dielectrics are also vulnerable. Smaller structures are more vulnerable because of their lower capacitance, meaning the same amount of charge carriers charges the capacitor to a higher voltage. All thin layers of dielectrics are vulnerable; hence, chips made by processes employing thicker oxide layers are less vulnerable.\nCurrent-induced failures are more common in bipolar junction devices, where Schottky and PN junctions are predominant. The high power of the discharge, above 5 kilowatts for less than a microsecond, can melt and vaporise materials. Thin-film resistors may have their value altered by a discharge path forming across them, or having part of the thin film vaporized; this can be problematic in precision applications where such values are critical.\nNewer CMOS output buffers using lightly doped silicide drains are more ESD sensitive; the N-channel driver usually suffers damage in the oxide layer or n+/p well junction. This is caused by current crowding during the snapback of the parasitic NPN transistor. In P/NMOS totem-pole structures, the NMOS transistor is almost always the one damaged. The structure of the junction influences its ESD sensitivity; corners and defects can lead to current crowding, reducing the damage threshold. Forward-biased junctions are less sensitive than reverse-biased ones because the Joule heat of forward-biased junctions is dissipated through a thicker layer of the material, as compared to the narrow depletion region in reverse-biased junction.\nPassive element failures.\nResistors.\nResistors can fail open or short, alongside their value changing under environmental conditions and outside performance limits. Examples of resistor failures include:\nPotentiometers and trimmers.\nPotentiometers and trimmers are three-terminal electromechanical parts, containing a resistive path with an adjustable wiper contact. Along with the failure modes for normal resistors, mechanical wear on the wiper and the resistive layer, corrosion, surface contamination, and mechanical deformations may lead to intermittent path-wiper resistance changes, which are a problem with audio amplifiers. Many types are not perfectly sealed, with contaminants and moisture entering the part; an especially common contaminant is the solder flux. Mechanical deformations (like an impaired wiper-path contact) can occur by housing warpage during soldering or mechanical stress during mounting. Excess stress on leads can cause substrate cracking and open failure when the crack penetrates the resistive path.\nCapacitors.\nCapacitors are characterized by their capacitance, parasitic resistance in series and parallel, breakdown voltage and dissipation factor; both parasitic parameters are often frequency- and voltage-dependent. Structurally, capacitors consist of electrodes separated by a dielectric, connecting leads, and housing; deterioration of any of these may cause parameter shifts or failure. Shorted failures and leakage due to increase of parallel parasitic resistance are the most common failure modes of capacitors, followed by open failures. Some examples of capacitor failures include:\nElectrolytic capacitors.\nIn addition to the problems listed above, electrolytic capacitors suffer from these failures:\nMetal oxide varistors.\nMetal oxide varistors typically have lower resistance as they heat up; if connected directly across a power bus, for protection against voltage spikes, a varistor with a lowered trigger voltage can slide into catastrophic thermal runaway and sometimes a small explosion or fire. To prevent this, the fault current is typically limited by a thermal fuse, circuit breaker, or other current limiting device.\nMEMS failures.\nMicroelectromechanical systems suffer from various types of failures:\nRecreating failure modes.\nIn order to reduce failures, a precise knowledge of bond strength quality measurement during product design and subsequent manufacture is of vital importance. The best place to start is with the failure mode. This is based on the assumption that there is a particular failure mode, or range of modes, that may occur within a product. It is therefore reasonable to assume that the bond test should replicate the mode, or modes of interest. However, exact replication is not always possible. The test load must be applied to some part of the sample and transferred through the sample to the bond. If this part of the sample is the only option and is weaker than the bond itself, the sample will fail before the bond.", "Engineering,_Manufacturing": 0.999985218, "qwen": "Yes"}
{"id": "45573249", "revid": "27233263", "url": "https://en.wikipedia.org/wiki?curid=45573249", "title": "Power integrity", "text": "Power integrity or PI is an analysis to check whether the desired voltage and current are met from source to destination. Today, power integrity plays a major role in the success and failure of new electronic products. There are several coupled aspects of PI: on the chip, in the chip package, on the circuit board, and in the system. Four main issues must be resolved to ensure power integrity at the printed circuit board level:\nPower distribution network.\nThe current path from the power supply through the PCB and IC package to the die (consumer) is called the power distribution network. Its role is to transfer the power to the consumers with little DC voltage drop, and to allow little ripple induced by dynamic current at the consumer (switching current). The DC voltage drop occurs if there is too much resistance in the plane or power traces leading from the VRM (Voltage Regulator Module) to the consumer. This can be countered by raising the voltage on the VRM, or extending the \"sense\" point of the VRM to the consumer.\nDynamic current occurs when the consumer switches its transistors, typically triggered by a clock signal. This dynamic current can be considerably larger than the static current (internal leakage) of the consumer. This fast change in current consumption can pull the voltage of the rail down, or cause it to spike, creating a voltage ripple. This change in current happens much faster than the VRM can react. The switching current must therefore be handled by decoupling capacitors.\nThe noise or voltage ripple must be handled differently depending on the frequency of operation. The highest frequencies must be handled on-die. This noise is decoupled by parasitic coupling on the die, and capacitive coupling between metal layers. Frequencies above 50100MHz must be handled on the package. This is done by on-package capacitors. Frequencies below 100MHz are handled on the PCB by plane capacitance and using decoupling capacitors. Capacitors work on different frequencies depending on their type, capacitance and physical size. It is therefore necessary to utilize multiple capacitors of different sizes to ensure a low PDN impedance across the frequency range.\nThe physical size of the capacitors affect its parasitic inductance. The parasitic inductance creates impedance spikes at certain frequencies. Physically smaller capacitors are therefore better. The placement of the capacitors is of varying importance depending on its frequency of operation. The smallest value capacitors should be as close as possible to the consumer to minimize the AC current loop area. Larger capacitors in the microfarad range can be placed more or less anywhere.\nTarget impedance.\nThe target impedance is the impedance at which the ripple created by the dynamic current of the specific consumer is within the specified range. The target impedance is given by the following equation\nIn addition to the target impedance, it is important to know which frequencies it applies, and at which frequency the consumer package is responsible (this is specified in the datasheet of the specific consumer IC).\nOne usually use some form of simulation when designing the PDN to ensure that the PDN meets the target impedance. This can be done by SPICE simulation, chip vendor tools, capacitor vendor tools, or by tools embedded in the EDA software.", "Engineering,_Manufacturing": 0.9985835552, "qwen": "Yes"}
{"id": "6821846", "revid": "45882132", "url": "https://en.wikipedia.org/wiki?curid=6821846", "title": "Bexel", "text": "SM Bexel Co, Ltd. (, formerly known as Bexel) is a South Korean chemical company specializing in battery manufacture. It is headquartered in Yangpyeong-dong Yeongdeungpo-gu, Seoul and Gongdan-dong, Gumi, Gyeongsangbuk-do, South Korea. Founded in 1978, it also manufactures other electronic products. Manufacturing is based in Gumi, Gyeongsangbuk-do.", "Engineering,_Manufacturing": 1.0000036955, "qwen": "Yes"}
{"id": "32979095", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=32979095", "title": "Supply chain engineering", "text": "Supply chain engineering is the engineering discipline that concerns the planning, design, and operation of supply chains. Some of its main areas include logistics, production, and pricing. It involves various areas in mathematical modelling such as operations research, machine learning, and optimization, which are usually implemented using software.\nSupply chain engineering draws heavily from, and overlaps with other engineering disciplines, such as industrial engineering, manufacturing engineering, systems engineering, information engineering, and software engineering. Although they have the same goals, supply chain engineering is focused on a mathematical model-based approach, whereas supply chain management is focused on a more traditional management and business-based one. Supply chain engineering can be considered to include supply chain optimization, although the latter could also be done using more qualitative management-based approaches, which is less of a focus in supply chain engineering.\nApplications.\nSupply chain engineering is applied to all parts of supply chains, including:\nTechniques.\nSupply chain engineering uses a wide variety of mathematical techniques such as:", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "41088004", "revid": "9676078", "url": "https://en.wikipedia.org/wiki?curid=41088004", "title": "Manoir Industries", "text": "Manoir Industries is a global metal processing company mainly focusing on high tech casting and forging components in petrochemical, nuclear, oil and gas, civil engineering, energy, defense, heavy weight trucks, tractors and aerospace markets. Manoir Industries employs 1,400 workers in 7 manufacturing locations in France, the United Kingdom, India and China.\nHistory.\nManoir Industries was created in 1917 in the commune of Pîtres in northwestern France. It was built between the towns of Pîtres and Le Manoir, from the latter of which comes its trade name. Manoir has become the Manoir Industries group by successive acquisitions. From 1917 to 1995, Manoir Industries acquired forging plants including Bouzonville, and Manoir Custines then Saint-Brieuc's foundry dedicated to wear parts. In 1994, Manoir expanded to a worldwide presence with a joint-venture in China becoming Yantai Manoir in 2006. In 2008 Hi-Tech Fabrication, a welding company located in the United Kingdom, joined the group, and in 2010 Kartik Steels also became part of Manoir. Kartik, specializing in tube supports for petrochemical furnaces, is a foundry in Chennai, India.\nOn February 28, 2013, the Yantai Taihai Group, a Manoir Industries partner for 15 years and a leading private company in China for nuclear casting and forging components, became Manoir's newest shareholder and committed to a long-term partnership with Manoir by speeding-up investments and building-up its international position.\nManufacturing process.\nManoir Industries technologies and know-how cover steel casting (static and centrifugal casting), forging (close-die, extrusion, welding), and provide ‘ready-to-assemble’ gear grinding and cutting, machined, surface treated, painted, shotblasted, coated parts to its customers.\nIn forging or casting processes, small- and mid-size batches of various morphologies are manufactured in a large range of alloys and are undergo controls meeting customers quality requirements:\nThe Petrochemical and Nuclear BU with the Pîtres, Burton-on-Trent, Yantai and Chennai plants offer high technology components to withstand high temperatures. The Excellence center, based in Pîtres and historical innovator of high temperature alloys, guarantees the process and quality for Manoir's Petrochemical plants.\nThe Manoir Forging Solutions with the Bouzonville forging plant and Manoir Engrenages provide all the closed-die, extrusion, gear grinding and cutting, machining and control processes for parts operating under severe conditions (nuclear, defense, oil&gas, mine, civil engineering, transport (heavy weight trucks and railways components), tractors and aerospace...).\nInnovation and customers service.\nManoir Industries develop high-temperature alloys which increase the life cycle of components and improve the existing solutions. Manoir AlloyServices enhance the performance of petrochemical facilities\nBouzonville’designer of forged components works with clients, from the design stage to the delivery of ready-to-assemble sets.", "Engineering,_Manufacturing": 1.0000071526, "qwen": "Yes"}
{"id": "16808662", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=16808662", "title": "Stand-up pouch", "text": "A stand-up pouch or doypack is a type of flexible packaging that is able to stand erect on its bottom for display, storage, and convenience. It has characteristics of plastic bags, water bottles, and retort pouches. The bottom part of a stand-up pouch is gusseted to provide support for display or use.\nStand-up pouches are commonly used for food packaging. They can be aseptically filled or filled on normal packaging lines.\nHistory.\nEarly work on stand-up pouches was conducted in France by Leon and Louis Doyen. Doyen was president of Thimonnier Company, which trademarked the name \"Doypack\" (from \"DOY\"en \"PACK\"aging\").\nDevelopment of materials, design options, and equipment increased in the 1980s and 1990s. Development of the retort pouch was closely related. It is currently a very widely used package form.\nConstruction.\nThe flexible pouches are usually constructed of multi-layer materials: various plastic films, paper, foil, etc. Pouches are often printed with high-impact graphics or sometimes have attached labels. The materials must have specialized heat-seal properties to allow conversion into pouches.\nThe most common pouch has bottom gussets to form a \"W\" which opens to allow a flat bottom. Side gussets are also sometimes used. Several design options are available.\nInclusion of pour spouts and re-closable zip strips is common.\nEquipment.\nThe packaging machinery involved typically forms the pouch from preprinted roll stock. The preformed pouches are shipped to a packager where they are filled and the top is sealed.\nThe alternative is an integral form-fill-seal machine, whether vertical or horizontal. The equipment forms the pouches, fills the pouches in-line, and seals them. With foods, drinks, or medical products, special sanitizing and wash-down requirements are critical. \nThe resulting equipment is sometimes complex and expensive. Packagers who do not have the volume to fill a machine to its capacity often use contract packagers.", "Engineering,_Manufacturing": 0.999984026, "qwen": "Yes"}
{"id": "3551042", "revid": "34290787", "url": "https://en.wikipedia.org/wiki?curid=3551042", "title": "Advanced planning and scheduling", "text": "Advanced planning and scheduling (APS, also known as advanced manufacturing) refers to a manufacturing management process by which raw materials and production capacity are optimally allocated to meet demand. APS is especially well-suited to environments where simpler planning methods cannot adequately address complex trade-offs between competing priorities. Production scheduling is intrinsically very difficult due to the (approximately) factorial dependence of the size of the solution space on the number of items/products to be manufactured.\nDifficulty of production planning.\nTraditional production planning and scheduling systems (such as manufacturing resource planning) use a stepwise procedure to allocate material and production capacity. This approach is simple but cumbersome, and does not readily adapt to changes in demand, resource capacity or material availability. Materials and capacity are planned separately, and many systems do not consider material or capacity constraints, leading to infeasible plans. However, attempts to change to the new system have not always been successful, which has called for the combination of management philosophy with manufacturing.\nUnlike previous systems, APS simultaneously plans and schedules production based on available materials, labor and plant capacity.\nAPS has commonly been applied where one or more of the following conditions are present:\nAdvanced planning & scheduling software enables manufacturing scheduling and advanced scheduling optimization within these environments.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "40769", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=40769", "title": "Balancing network", "text": "In a hybrid set, hybrid coil, or resistance hybrid, balancing network is a circuit used to match, \"i.e.\", to balance, the impedance of a uniform transmission line, (e.g., a twisted metallic pair, coaxial cable, etc.) over a selected range of frequencies. A balancing network is required to ensure isolation between the two ports of the four-wire side of the hybrid.\nA balancing network can also be a device used between a balanced device or line and an unbalanced device or line for the purpose of transforming from balanced to unbalanced or from unbalanced to balanced.\nSource: from Federal Standard 1037C and from MIL-STD-188", "Engineering,_Manufacturing": 1.0000013113, "qwen": "Yes"}
{"id": "41073", "revid": "44120587", "url": "https://en.wikipedia.org/wiki?curid=41073", "title": "Dual in-line package", "text": "In microelectronics, a dual in-line package (DIP or DIL) is an electronic component package with a rectangular housing and two parallel rows of electrical connecting pins. The package may be through-hole mounted to a printed circuit board (PCB) or inserted in a socket. The dual-inline format was invented by Don Forbes, Rex Rice and Bryant Rogers at Fairchild R&D in 1964, when the restricted number of leads available on circular transistor-style packages became a limitation in the use of integrated circuits. Increasingly complex circuits required more signal and power supply leads (as observed in Rent's rule); eventually microprocessors and similar complex devices required more leads than could be put on a DIP package, leading to development of higher-density chip carriers. Furthermore, square and rectangular packages made it easier to route printed-circuit traces beneath the packages.\nA DIP is usually referred to as a DIP\"n\", where \"n\" is the total number of pins. For example, a microcircuit package with two rows of seven vertical leads would be a DIP14. The photograph at the upper right shows three DIP14 ICs. Common packages have as few as three and as many as 64 leads. Many analog and digital integrated circuit types are available in DIP packages, as are arrays of transistors, switches, light emitting diodes, and resistors. DIP plugs for ribbon cables can be used with standard IC sockets.\nDIP packages are usually made from an opaque molded epoxy plastic pressed around a tin-, silver-, or gold-plated lead frame that supports the device die and provides connection pins. Some types of IC are made in ceramic DIP packages, where high temperature or high reliability is required, or where the device has an optical window to the interior of the package. Most DIP packages are secured to a PCB by inserting the pins through holes in the board and soldering them in place. Where replacement of the parts is necessary, such as in test fixtures or where programmable devices must be removed for changes, a DIP socket is used. Some sockets include a zero insertion force (ZIF) mechanism.\nVariations of the DIP package include those with only a single row of pins, e.g. a resistor array, possibly including a heat sink tab in place of the second row of pins, and types with four rows of pins, two rows, staggered, on each side of the package. DIP packages have been mostly displaced by surface-mount package types, which avoid the expense of drilling holes in a PCB and which allow higher density of interconnections.\nApplications.\nTypes of devices.\nDIPs are commonly used for integrated circuits (ICs). Other devices in DIP packages include resistor networks, DIP switches, LED segmented and bar graph displays, and electromechanical relays.\nDIP connector plugs for ribbon cables are common in computers and other electronic equipment.\nDallas Semiconductor manufactured integrated DIP real-time clock (RTC) modules which contained an IC chip and a non-replaceable 10-year lithium battery.\nDIP header blocks on to which discrete components could be soldered were used where groups of components needed to be easily removed, for configuration changes, optional features or calibration.\nUses.\nThe original dual-in-line package was invented by Bryant \"Buck\" Rogers in 1964 while working for Fairchild Semiconductor. The first devices had 14 pins and looked much like they do today. The rectangular shape allowed integrated circuits to be packaged more densely than previous round packages. The package was well-suited to automated assembly equipment; a PCB could be populated with scores or hundreds of ICs, then all the components on the circuit board could be soldered at one time on a wave soldering machine and passed on to automated testing machines, with very little human labor required. DIP packages were still large with respect to the integrated circuits within them. By the end of the 20th century, surface-mount packages allowed further reduction in the size and weight of systems. DIP chips are still popular for circuit prototyping on a breadboard because of how easily they can be inserted and used there.\nDIPs were the mainstream of the microelectronics industry in the 1970s and 1980s. Their use has declined in the first decade of the 21st century due to the emerging new surface-mount technology (SMT) packages such as plastic leaded chip carrier (PLCC) and small-outline integrated circuit (SOIC), though DIPs continued in extensive use through the 1990s, and still continue to be used substantially as the year 2011 passes. Because some modern chips are available only in surface-mount package types, a number of companies sell various prototyping adapters to allow those surface-mount devices (SMD) to be used like DIP devices with through-hole breadboards and soldered prototyping boards (such as stripboard and perfboard). (SMT can pose quite a problem, at least an inconvenience, for prototyping in general; most of the characteristics of SMT that are advantages for mass production are difficulties for prototyping.)\nFor programmable devices like EPROMs and GALs, DIPs remained popular for many years due to their easy handling with external programming circuitry (i.e., the DIP devices could be simply plugged into a socket on the programming device.) However, with In-System Programming (ISP) technology now state of the art, this advantage of DIPs is rapidly losing importance as well.\nThrough the 1990s, devices with fewer than 20 leads were manufactured in a DIP format in addition to the newer formats. Since about 2000, newer devices are often unavailable in the DIP format.\nMounting.\nDIPs can be mounted either by through-hole soldering or in sockets. Sockets allow easy replacement of a device and eliminates the risk of damage from overheating during soldering. Generally sockets were used for high-value or large ICs, which cost much more than the socket. Where devices would be frequently inserted and removed, such as in test equipment or EPROM programmers, a zero insertion force socket would be used.\nDIPs are also used with breadboards, a temporary mounting arrangement for education, design development or device testing. Some hobbyists, for one-off construction or permanent prototyping, use point-to-point wiring with DIPs, and their appearance when physically inverted as part of this method inspires the informal term \"dead bug style\" for the method.\nConstruction.\nThe body (housing) of a DIP containing an IC chip is usually made from molded plastic or ceramic. The hermetic nature of a ceramic housing is preferred for extremely high reliability devices. However, the vast majority of DIPs are manufactured via a thermoset molding process in which an epoxy mold compound is heated and transferred under pressure to encapsulate the device. Typical cure cycles for the resins are less than 2 minutes and a single cycle may produce hundreds of devices.\nThe leads emerge from the longer sides of the package along the seam, parallel to the top and bottom planes of the package, and are bent downward approximately 90 degrees (or slightly less, leaving them angled slightly outward from the centerline of the package body). (The SOIC, the SMT package that most resembles a typical DIP, appears essentially the same, notwithstanding size scale, except that after being bent down the leads are bent upward again by an equal angle to become parallel with the bottom plane of the package.) In ceramic (CERDIP) packages, an epoxy or grout is used to hermetically seal the two halves together, providing an air and moisture tight seal to protect the IC die inside. Plastic DIP (PDIP) packages are usually sealed by fusing or cementing the plastic halves around the leads, but a high degree of hermeticity is not achieved because the plastic itself is usually somewhat porous to moisture and the process cannot ensure a good microscopic seal between the leads and the plastic at all points around the perimeter. However, contaminants are usually still kept out well enough that the device can operate reliably for decades with reasonable care in a controlled environment.\nInside the package, the lower half has the leads embedded, and at the center of the package is a rectangular space, chamber, or void into which the IC die is cemented. The leads of the package extend diagonally inside the package from their positions of emergence along the periphery to points along a rectangular perimeter surrounding the die, tapering as they go to become fine contacts at the die. Ultra-fine bond wires (barely visible to the naked human eye) are welded between these die periphery contacts and bond pads on the die itself, connecting one lead to each bond pad, and making the final connection between the microcircuits and the external DIP leads. The bond wires are not usually taut but loop upward slightly to allow slack for thermal expansion and contraction of the materials; if a single bond wire breaks or detaches, the entire IC may become useless. The top of the package covers all of this delicate assemblage without crushing the bond wires, protecting it from contamination by foreign materials.\nUsually, a company logo, alphanumeric codes and sometimes words are printed on top of the package to identify its manufacturer and type, when it was made (usually as a year and a week number), sometimes where it was made, and other proprietary information (perhaps revision numbers, manufacturing plant codes, or stepping ID codes.)\nThe necessity of laying out all of the leads in a basically radial pattern in a single plane from the die perimeter to two rows on the periphery of the package is the main reason that DIP packages with higher lead counts must have wider spacing between the lead rows, and it effectively limits the number of leads which a practical DIP package may have. Even for a very small die with many bond pads (e.g. a chip with 15 inverters, requiring 32 leads), a wider DIP would still be required to accommodate the radiating leads internally. This is one of the reasons that four-sided and multiple rowed packages, such as PGAs, were introduced (around the early 1980s).\nA large DIP package (such as the DIP64 used for the Motorola 68000 CPU) has long leads inside the package between pins and the die, making such a package unsuitable for high speed devices.\nSome other types of DIP devices are built very differently. Most of these have molded plastic housings and straight leads or leads that extend directly out of the bottom of the package. For some, LED displays particularly, the housing is usually a hollow plastic box with the bottom/back open, filled (around the contained electronic components) with a hard translucent epoxy material from which the leads emerge. Others, such as DIP switches, are composed of two (or more) plastic housing parts snapped, welded, or glued together around a set of contacts and tiny mechanical parts, with the leads emerging through molded-in holes or notches in the plastic.\nVariants.\nSeveral DIP variants for ICs exist, mostly distinguished by packaging material:\nEPROMs were sold in ceramic DIPs manufactured with a circular window of clear quartz over the chip die to allow the part to be erased by ultraviolet light. Often, the same chips were also sold in less expensive windowless PDIP or CERDIP packages as one-time programmable (OTP) versions. Windowed and windowless packages were also used for microcontrollers, and other devices, containing EPROM memory. Windowed CERDIP-packaged EPROMs were used for the BIOS ROM of many early IBM PC clones with an adhesive label covering the window to prevent inadvertent erasure through exposure to ambient light.\nMolded plastic DIPs are much lower in cost than ceramic packages; one 1979 study showed that a plastic 14 pin DIP cost around US$0.063 and a ceramic package cost US$0.82.\nSingle in-line.\nA single in-line package (SIP or SIL) has one row of connecting pins. It is not as popular as the DIP, but has been used for packaging RAM chips and multiple resistors with a common pin. As compared to DIPs with a typical maximum pin count of 64, SIPs have a typical maximum pin count of 24 with lower package costs.\nOne variant of the single in-line package uses part of the lead frame for a heat sink tab. This multi-leaded power package is useful for such applications as audio power amplifiers, for example.\nQuad in-line.\nThe QIP, sometimes called a QIL package, has the same dimensions as a DIL package, but the leads on each side are bent into an alternating zigzag configuration so as to fit four lines of solder pads (instead of two with a DIL). The QIL design increased the spacing between solder pads without increasing package size, for two reasons: \nLead count and spacing.\nCommonly found DIP packages that conform to JEDEC standards use an inter-lead spacing (lead pitch) of (JEDEC MS-001BA). Row spacing varies depending on lead counts, with 0.3 in. (7.62 mm) (JEDEC MS-001) or 0.6 inch (15.24 mm) (JEDEC MS-011) the most common. Less common standardized row spacings include 0.4 inch (10.16 mm) (JEDEC MS-010) and 0.9 inch (22.86 mm), as well as a row spacing of 0.3 inch, 0.6 inch or 0.75 inch with a 0.07 inch (1.778 mm) lead pitch.\nThe former Soviet Union and Eastern bloc countries used similar packages, but with a metric pin-to-pin spacing of 2.5 mm rather than .\nThe number of leads is always even. For 0.3 inch spacing, typical lead counts are 8, 14, 16, 18, and 28; less common are 4, 6, 20, and 24 lead counts. To have an even number of leads some DIPs have unused not connected (NC) leads to the internal chip, or are duplicated, e.g. two ground pins. For 0.6 inch spacing, typical lead counts are 24, 28, 32, and 40; less common are 36, 42, 48, 52, and 64 lead counts. Some microprocessors, such as the Motorola 68000 and Zilog Z180, used lead counts as high as 64; this is typically the maximum number of leads for a DIP package.\nOrientation and lead numbering.\nAs shown in the diagram, leads are numbered consecutively from Pin 1. When the identifying notch in the package is at the top, Pin 1 is the top left corner of the device. Sometimes Pin 1 is identified with an indent or paint dot mark.\nFor example, for a 14-lead DIP, with the notch at the top, the left leads are numbered from 1 to 7 (top to bottom) and the right row of leads are numbered 8 to 14 (bottom to top).\nSome DIP devices, such as segmented LED displays, relays, or those that replace leads with a heat sink fin, skip some leads; the remaining leads are numbered as if all positions had leads.\nIn addition to providing for human visual identification of the orientation of the package, the notch allows automated chip-insertion machinery to confirm correct orientation of the chip by mechanical sensing.\nDescendants.\nThe SOIC (Small Outline IC), a surface-mount package which is currently very popular, particularly in consumer electronics and personal computers, is essentially a shrunk version of the standard IC PDIP, the fundamental difference which makes it an SMT device being a second bend in the leads to flatten them parallel to the bottom plane of the plastic housing. The SOJ (Small Outline J-lead) and other SMT packages with \"SOP\" (for \"Small Outline Package\") in their names can be considered further relatives of the DIP, their original ancestor. SOIC packages tend to have half the pitch of DIP, and SOP are half that, a fourth of DIP. (0.1\"/2.54 mm, 0.05\"/1.27 mm, and 0.025\"/0.635 mm, respectively)\nPin grid array (PGA) packages may be considered to have evolved from the DIP. PGAs with the same pin centers as most DIPs were popular for microprocessors from the early to mid-1980s through the 1990s. Owners of personal computers containing Intel 80286 through P5 Pentium processors may be most familiar with these PGA packages, which were often inserted into ZIF sockets on motherboards. The similarity is such that a PGA socket may be physically compatible with some DIP devices, though the converse is rarely true.", "Engineering,_Manufacturing": 0.9998481274, "qwen": "Yes"}
{"id": "41266", "revid": "46262746", "url": "https://en.wikipedia.org/wiki?curid=41266", "title": "Insertion loss", "text": "In telecommunications, insertion loss is the loss of signal power resulting from the insertion of a device in a transmission line or optical fiber and is usually expressed in decibels (dB). \nIf the power transmitted to the load before insertion is \"P\"T and the power received by the load after insertion is \"P\"R, then the insertion loss in decibels is given by,\nElectronic filters.\nInsertion loss is a figure of merit for an electronic filter and this data is generally specified with a filter. Insertion loss is defined as a ratio of the signal level in a test configuration without the filter installed (formula_2) to the signal level with the filter installed (formula_3). This ratio is described in decibels by the following equation:\nFor passive filters, formula_3 will be smaller than formula_2. In this case, the insertion loss is positive and measures how much smaller the signal is after adding the filter.\nLink with scattering parameters.\nIn case the two measurement ports use the same reference impedance, the insertion loss (formula_7) is defined as: \nHere formula_9 is one of the scattering parameters. Insertion loss is the extra loss produced by the introduction of the DUT between the 2 reference planes of the measurement. The extra loss can be introduced by intrinsic loss in the DUT and/or mismatch. In case of extra loss the insertion loss is defined to be positive.", "Engineering,_Manufacturing": 0.9988093376, "qwen": "Yes"}
{"id": "12144923", "revid": "237572", "url": "https://en.wikipedia.org/wiki?curid=12144923", "title": "Adams (1903 automobile)", "text": "Adams was an automobile introduced manufactured by the Adams Manufacturing Co. Ltd. from 1903 to 1906. It was developed by H. Adams, of Tunbridge Wells, Kent, England, who offered a conversion set that converted horse-drawn carriages into motorized automobiles. The engine was mounted on a swivelling fore-carriage, and steering was achieved through wheel and vertical column. In 1905, Adams produced a small 2-cylinder car sold under the name 'One of the Best'.", "Engineering,_Manufacturing": 0.999969244, "qwen": "Yes"}
{"id": "744482", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=744482", "title": "Brushed metal", "text": "Brushed or dull polished metal is metal with a unidirectional satin finish. It is produced by polishing the metal with a 120–180 grit belt or wheel then softening with an 80–120 grit greaseless compound or a medium non-woven abrasive belt or pad.\nCommonly brushed metals include stainless steel, aluminium and nickel. Brushed finishes are popular in both small appliances and whiteware, and feature in architecture and automotive design. The Gateway Arch and DMC DeLorean are both clad in brushed stainless steel. The intensity of the brushed finish is specified as a surface roughness and is typically 0.5–1.5 micrometres Ra.\nCharacteristics.\nBrushing gives metal a distinctive look, as it retains some but not all of its metallic lustre and is given a pattern of very fine lines parallel to the brushing direction. For this reason, it is commonly used for decorative items like jewelry and watches.\nA brushed finish is susceptible to damage. Brushed finishes also typically have a detrimental effect on corrosion resistance. In particular the brushed texture limits the ability of fluid to bead on the material surface. In the case of stainless steel the grooves of the finish can accumulate chloride ions which break down the chromium oxide passivation layer, enabling rusting to occur.", "Engineering,_Manufacturing": 0.9985408783, "qwen": "Yes"}
{"id": "12235954", "revid": "1168245163", "url": "https://en.wikipedia.org/wiki?curid=12235954", "title": "Cold working", "text": "\nIn metallurgy, cold forming or cold working is any metalworking process in which metal is shaped below its recrystallization temperature, usually at the ambient temperature. Such processes are contrasted with hot working techniques like hot rolling, forging, welding, etc. The same or similar terms are used in glassmaking for the equivalents; for example cut glass is made by \"cold work\", cutting or grinding a formed object.\nCold forming techniques are usually classified into four major groups: squeezing, bending, drawing, and shearing. They generally have the advantage of being simpler to carry out than hot working techniques. \nUnlike hot working, cold working causes the crystal grains and inclusions to distort following the flow of the metal; which may cause work hardening and anisotropic material properties. Work hardening makes the metal harder, stiffer, and stronger, but less plastic, and may cause cracks of the piece.\nThe possible uses of cold forming are extremely varied, including large flat sheets, complex folded shapes, metal tubes, screw heads and threads, riveted joints, and much more.\nProcesses.\nThe following is a list of cold forming processes:\nAdvantages.\nAdvantages of cold working over hot working include:\nDepending on the material and extent of deformation, the increase in strength due to work hardening may be comparable to that of heat treating. Therefore, it is sometimes more economical to cold work a less costly and weaker metal than to hot work a more expensive metal that can be heat treated, especially if precision or a fine surface finish is required as well. \nThe cold working process also reduces waste as compared to machining, or even eliminates with near net shape methods. The material savings becomes even more significant at larger volumes, and even more so when using expensive materials, such as copper, nickel, gold, tantalum, and palladium. The saving on raw material as a result of cold forming can be very significant, as is saving machining time. Production cycle times when cold working are very short. On multi-station machinery, production cycle times are even less. This can be very advantageous for large production runs.\nDisadvantages.\nSome disadvantages and problems of cold working are:\nThe need for heavier equipment and harder tools may make cold working suitable only for large volume manufacturing industry.\nThe loss of plasticity due to work hardening may require intermediate annealings, and a final annealing to relieve residual stress and give the desired properties to the manufactured object. These extra steps would negate some of the economic advantages of cold forming over hot forming.\nCold worked items suffer from a phenomenon known as \"springback\", or \"elastic springback\". After the deforming force is removed from the workpiece, the workpiece springs back slightly. The amount a material springs back is equal to the yield strain (the strain at the yield point) for the material.\nSpecial precautions may be needed to maintain the general shape of the workpiece during cold working, such as shot peening and equal channel angular extrusion.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "64138285", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=64138285", "title": "Five-bar linkage", "text": "In kinematics, a five-bar linkage is a mechanism with two degrees of freedom that is constructed from five links that are connected together in a closed chain. All links are connected to each other by five joints in series forming a loop. One of the links is the ground or base. This configuration is also called a pantograph, however, it is not to be confused with the parallelogram-copying linkage pantograph.\nThe linkage can be a one-degree-of-freedom mechanism if two gears are attached to two links and are meshed together, forming a geared five-bar mechanism.\nRobotic configuration.\nWhen controlled motors actuate the linkage, the whole system (a mechanism and its actuators) becomes a robot. This is usually done by placing two servomotors (to control the two degrees of freedom) at the joints A and B, controlling the angle of the links L2 and L5. L1 is the grounded link. In this configuration, the controlled endpoint or end-effector is the point D, where the objective is to control its x and y coordinates in the plane in which the linkage resides. The angles theta 1 and theta 2 can be calculated as a function of the x,y coordinates of point D using trigonometric functions. This robotic configuration is a parallel manipulator. It is a parallel configuration robot as it is composed of two controlled serial manipulators connected to the endpoint.\nUnlike a serial manipulator, this configuration has the advantage of having both motors grounded at the base link. As the motor can be quite massive, this significantly decreases the total moment of inertia of the linkage and improves backdrivability for haptic feedback applications. On the other hand, workspace reached by the endpoint is usually significantly smaller than that of a serial manipulator.\nKinematics and dynamics.\nBoth the forward and inverse kinematics of this robotic configuration can be found in closed-form equations through geometric relationships. Different methods of finding both have been done by Campion and Hayward. Dynamic modeling of this robotic configuration has been done by Khalil and Abu Seif, forming an equations of motion relating the torques applied at motor with the angles at the joints. The model assumes all links are rigid with center of gravity at their centers, and zero-stiffness at all joints.\nApplications.\nThis robotic linkage is used in many different fields ranging from prosthetics to haptic feedback. This design has been explored in several haptic feedback devices for general force feedback. It has also been used in the automatic drawing toy WeDraw. A novel Ackermann-type steering mechanism design by Zhao et al. utilized a five-bar linkage instead of the regular four-bar linkage. A prosthetic ankle-foot by Dong et al. used a geared five-bar spring mechanism to simulate the stiffness and damping behavior of a real foot.", "Engineering,_Manufacturing": 0.9992721677, "qwen": "Yes"}
{"id": "61309934", "revid": "26557663", "url": "https://en.wikipedia.org/wiki?curid=61309934", "title": "2021 Africa Cup of Nations qualification preliminary round", "text": "The preliminary round of the 2021 Africa Cup of Nations qualification tournament decided four teams which advanced to the group stage of the qualification tournament. The preliminary round consisted of the eight lowest-ranked teams among the 52 entrants: Liberia, Mauritius, Gambia, South Sudan, Chad, São Tomé and Príncipe, Seychelles, and Djibouti.\nThe eight teams were drawn into four ties and played in home-and-away two-legged format. The four winners advanced to the group stage to join the 44 teams which entered directly.\nThe first legs were played on 9 October, and the second legs were played on 13 October 2019.\nMatches.\n\n\"1–1 on aggregate. Chad won 5–4 on penalties and advanced to qualification Group A.\"\n\"South Sudan won 3–1 on aggregate and advanced to qualification Group B.\"\n\"São Tomé and Príncipe won 5–2 on aggregate and advanced to qualification Group C.\"\n\"2–2 on aggregate. Gambia won 3–2 on penalties and advanced to qualification Group D.\"", "Engineering,_Manufacturing": 0.9997275472, "qwen": "Yes"}
{"id": "32885372", "revid": "17842333", "url": "https://en.wikipedia.org/wiki?curid=32885372", "title": "Sverker 21", "text": "Sverker 21 is a tool steel manufactured by Uddeholms AB. It is primarily used for Cold Work applications such as blanking, piercing, cropping, bending, forming and cutting. It's a proprietary equivalent to D2 [tool steel].\nProperties.\nSverker 21 is characterized by high compressive strength, high\nsurface hardness after hardening, good though-hardening properties and high wear\nresistance (abrasive type of wear profile). These characteristics combine to give a steel\nsuitable for the manufacture of medium run tooling for applications where abrasive\nwear is dominant and the risk of chipping or cracking is not so high, e.g. for blanking and\nforming of thinner, harder work materials.\nApplication areas.\nIt is a 12% chromium steel suitable for medium production volume tooling where the production materials cause abrasive wear and the risk of chipping is not so high.\nOther Uddeholm Cold Work Steels.\nArne, \nCaldie, \nCalmax, \nRigor, \nSleipner, \nSverker 3, \nUnimax, \nVanadis 4 Extra, \nVanadis 6, \nVanadis 10, \nVanadis 23, \nVancron 40, \nUHB 11, \nFormax, \nHoldax,", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "32900024", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=32900024", "title": "Bliss (automobile)", "text": "The Bliss automobile was manufactured by the E. W. Bliss Company of Brooklyn, New York, in 1906. The company was founded in 1867 and for a short duration, diversified into automobile manufacturing.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "71000130", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=71000130", "title": "Cooper 500", "text": "The Cooper 500, also referred to as the T2/T3 (Type 2/Type 3), was a prototype 500cc (predecessor to Formula 3) open-wheel racing car designed and built by the Cooper Car Company in Surbiton, Surrey, England, and was their first ever car. The first post-war prototypes were built in 1946, shortly after the end of the Second World War. Since materials were in short supply immediately after World War II, the prototypes were constructed by joining two old Fiat Topolino front-ends together. It was powered by a JA Prestwich Industries (JAP) 4B Speedway single-cylinder motorcycle engine, which drives the rear wheels through a Triumph Speed Twin gearbox, via chain. It was succeeded by their first successful production car, the Mk.II, in 1948.", "Engineering,_Manufacturing": 0.9981335998, "qwen": "Yes"}
{"id": "71002788", "revid": "36055642", "url": "https://en.wikipedia.org/wiki?curid=71002788", "title": "2022–23 UEFA Europa Conference League qualifying phase and play-off round (Main Path)", "text": "This page summarises the Main Path matches of the 2022–23 UEFA Europa Conference League qualifying phase and play-off round.\nTimes are CEST , as listed by UEFA (local times, if different, are in parentheses).\nFirst qualifying round.\nSummary.\n\n\nMatches.\n\"Ħamrun Spartans won 4–2 on aggregate.\"\n\"Lechia Gdańsk won 6–2 on aggregate.\"\n\"Drita won 3–1 on aggregate.\"\n\"4–4 on aggregate. Paide Linnameeskond won 6–5 on penalties.\"\n\"Milsami Orhei won 2–0 on aggregate.\"\n\"Laçi won 1–0 on aggregate.\"\n\"Liepāja won 3–2 on aggregate.\"\n\"Mura won 4–2 on aggregate.\"\n\"KuPS won 2–0 on aggregate.\"\n\"Ružomberok won 2–0 on aggregate.\"\n\"Budućnost Podgorica won 4–2 on aggregate.\"\n\"Gżira United won 2–1 on aggregate.\"\n\"3–3 on aggregate. B36 Tórshavn won 4–3 on penalties.\"\n\"Olimpija Ljubljana won 3–2 on aggregate.\"\n\"St Joseph's won 1–0 on aggregate.\"\n\"Breiðablik won 5–1 on aggregate.\"\n\"DAC Dunajská Streda won 5–1 on aggregate.\"\n\"Víkingur won 3–1 on aggregate.\"\n\"2–2 on aggregate. Sligo Rovers won 4–3 on penalties.\"\n\"Tre Fiori won 4–1 on aggregate.\"\n\"Dinamo Minsk won 3–2 on aggregate.\"\n\"Tuzla City won 8–0 on aggregate.\"\n\"1–1 on aggregate. Saburtalo Tbilisi won 5–4 on penalties.\"\n\"Shkëndija won 4–2 on aggregate.\"\n\"Petrocub Hîncești won 1–0 on aggregate.\"\n\"Pogoń Szczecin won 4–2 on aggregate.\"\n\"2–2 on aggregate. Newtown won 4–2 on penalties.\"\n\"Crusaders won 4–3 on aggregate.\"\n\"SJK won 4–3 on aggregate.\"\n\"Riga won 4–0 on aggregate.\"\nSecond qualifying round.\nSummary.\n\n\n\nMatches.\n\"5–5 on aggregate. Gżira United won 3–1 on penalties.\"\n\"Aris won 7–2 on aggregate.\"\n\"APOEL won 2–0 on aggregate.\"\n\"Fehérvár won 5–3 on aggregate.\"\n\"İstanbul Başakşehir won 2–1 on aggregate.\"\n\"Neftçi Baku won 3–2 on aggregate.\"\n\"Ħamrun Spartans won 2–0 on aggregate.\"\n\"FCSB won 4–3 on aggregate.\"\n\"CSKA Sofia won 4–0 on aggregate.\"\n\"Hapoel Be'er Sheva won 3–1 on aggregate.\"\n\"Maccabi Tel Aviv won 3–0 on aggregate.\"\n\"Universitatea Craiova won 4–1 on aggregate.\"\n\"0–0 on aggregate. Paide Linnameeskond won 5–3 on penalties.\"\n\"Kisvárda won 2–0 on aggregate.\"\n\"Konyaspor won 5–0 on aggregate.\"\n\"3–3 on aggregate. Sepsi Sfântu Gheorghe won 4–2 on penalties.\"\n\"Kyzylzhar won 3–2 on aggregate.\"\n\"Young Boys won 4–0 on aggregate.\"\n\"Rapid Wien won 2–1 on aggregate.\"\n\"Lillestrøm won 6–2 on aggregate.\"\n\"Breiðablik won 3–2 on aggregate.\"\n\"1–1 on aggregate. St Patrick's Athletic won 6–5 on penalties.\"\n\"Slavia Prague won 11–0 on aggregate.\"\n\"Spartak Trnava won 6–2 on aggregate.\"\n\"Viborg won 2–0 on aggregate.\"\n\"DAC Dunajská Streda won 4–0 on aggregate.\"\n\"Brøndby won 5–1 on aggregate.\"\n\"AZ won 5–0 on aggregate.\"\n\"Sligo Rovers won 3–0 on aggregate.\"\n\"Molde won 6–2 on aggregate.\" \n\"Vaduz won 2–1 on aggregate.\"\n\"B36 Tórshavn won 1–0 on aggregate.\"\n\"Riga won 5–1 on aggregate.\"\n\"Basel won 3–1 on aggregate.\"\n\"Antwerp won 2–0 on aggregate.\"\n\"Petrocub Hîncești won 4–1 on aggregate.\"\n\"Čukarički won 8–1 on aggregate.\"\n\"Levski Sofia won 3–1 on aggregate.\"\n\"Vitória de Guimarães won 3–0 on aggregate.\"\n\"Djurgårdens IF won 4–1 on aggregate.\"\n\"AIK won 4–3 on aggregate.\"\n\"Shkëndija won 5–2 on aggregate.\"\n\"Raków Częstochowa won 6–0 on aggregate.\"\n\"KuPS won 6–3 on aggregate.\"\n\"Viking won 2–1 on aggregate.\"\nThird qualifying round.\nSummary.\n\n\n\nMatches.\n\"Raków Częstochowa won 3–0 on aggregate.\"\n\"2–2 on aggregate. AIK won 3–2 on penalties.\"\n\"Viking won 5–2 on aggregate.\"\n\"İstanbul Başakşehir won 6–1 on aggregate.\"\n\"Young Boys won 5–0 on aggregate.\"\n\"Anderlecht won 5–0 on aggregate.\"\n\"Viborg won 5–1 on aggregate.\"\n\"Hajduk Split won 3–2 on aggregate.\"\n\"2–2 on aggregate. Basel won 3–1 on penalties.\"\n\"Antwerp won 5–1 on aggregate.\"\n\"CSKA Sofia won 2–1 on aggregate.\"\n\"AZ won 7–1 on aggregate.\"\n\"APOEL won 1–0 on aggregate.\"\n\"FCSB won 2–0 on aggregate.\"\n\"Gil Vicente won 5–1 on aggregate.\"\n\"Wolfsberger AC won 4–0 on aggregate.\"\n\"Maccabi Tel Aviv won 3–2 on aggregate.\"\n\"Molde won 4–2 on aggregate.\"\n\"Rapid Wien won 3–2 on aggregate.\"\n\"Hapoel Be'er Sheva won 5–1 on aggregate.\"\n\"2–2 on aggregate. Ħamrun Spartans won 4–1 on penalties.\"\n\"Twente won 7–2 on aggregate.\"\n\"Universitatea Craiova won 3–1 on aggregate.\"\n\"Vaduz won 5–3 on aggregate.\"\n\"Djurgårdens IF won 6–2 on aggregate.\"\n\"Fehérvár won 7–1 on aggregate.\"\n\"Slavia Prague won 3–1 on aggregate.\"\nPlay-off round.\nSummary.\n\n\n\nMatches.\n\"Basel won 2–1 on aggregate.\"\n\"Vaduz won 2–1 on aggregate.\"\n\"Slavia Prague won 3–2 on aggregate.\"\n\"Djurgårdens IF won 5–3 on aggregate.\"\n\"Nice won 2–1 on aggregate.\"\n\"2–2 on aggregate. Hapoel Be'er Sheva won 4–3 on penalties.\"\n\"İstanbul Başakşehir won 4–2 on aggregate.\"\n\"FCSB won 4–3 on aggregate.\"\n\"Partizan won 7–4 on aggregate.\"\n\"Fiorentina won 2–1 on aggregate.\"\n\"Villarreal won 6–2 on aggregate.\"\n\"1. FC Köln won 4–2 on aggregate.\"\n\"West Ham United won 6–1 on aggregate.\"\n\"1–1 on aggregate. Anderlecht won 3–1 on penalties.\"\n\"Slovácko won 4–0 on aggregate.\"\n\"Molde won 4–1 on aggregate.\"\n\"AZ won 6–1 on aggregate.\"", "Engineering,_Manufacturing": 0.999845624, "qwen": "Yes"}
{"id": "31340342", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=31340342", "title": "Open-shop scheduling", "text": "Open-shop scheduling or open-shop scheduling problem (OSSP) is an optimization problem in computer science and operations research. It is a variant of optimal job scheduling. In a general job-scheduling problem, we are given \"n\" jobs \"J\"1, \"J\"2, ..., \"Jn\" of varying processing times, which need to be scheduled on \"m\" machines with varying processing power, while trying to minimize the makespan - the total length of the schedule (that is, when all the jobs have finished processing). In the specific variant known as \"open-shop scheduling\", each job consists of a set of \"operations\" \"O\"1, \"O\"2, ..., \"On\" which need to be processed in an \"arbitrary\" order. The problem was first studied by Teofilo F. Gonzalez and Sartaj Sahni in 1976.\nIn the standard three-field notation for optimal job-scheduling problems, the open-shop variant is denoted by O in the first field. For example, the problem denoted by \"O3|formula_1|formula_2\" is a 3-machines job-shop problem with unit processing times, where the goal is to minimize the maximum completion time.\nDefinition.\nThe input to the open-shop scheduling problem consists of a set of \"n\" jobs, another set of \"m\" workstations, and a two-dimensional table of the amount of time each job should spend at each workstation (possibly zero). Each job may be processed only at one workstation at a time, and each workstation can process only one job at a time. However, unlike the job-shop problem, the order in which the processing steps happen can vary freely. The goal is to assign a time for each job to be processed by each workstation, so that no two jobs are assigned to the same workstation at the same time, no job is assigned to two workstations at the same time, and every job is assigned to each workstation for the desired amount of time. The usual measure of quality of a solution is its makespan, the amount of time from the start of the schedule (the first assignment of a job to a workstation) to its end (the finishing time of the last job at the last workstation).\nComputational complexity.\nThe open-shop scheduling problem can be solved in polynomial time for instances that have only two workstations or only two jobs. It may also be solved in polynomial time when all nonzero processing times are equal: in this case the problem becomes equivalent to edge coloring a bipartite graph that has the jobs and workstations as its vertices, and that has an edge for every job-workstation pair that has a nonzero processing time. The color of an edge in the coloring corresponds to the segment of time at which a job-workstation pair is scheduled to be processed. Because the line graphs of bipartite graphs are perfect graphs, bipartite graphs may be edge-colored in polynomial time.\nFor three or more workstations, or three or more jobs, with varying processing times, open-shop scheduling is NP-hard.", "Engineering,_Manufacturing": 0.9500077367, "qwen": "Yes"}
{"id": "37411947", "revid": "17218984", "url": "https://en.wikipedia.org/wiki?curid=37411947", "title": "Conveyor pulley", "text": "A conveyor pulley is a mechanical device used to change the direction of the belt in a conveyor system, to drive the belt, and to tension the belt. Modern pulleys are made of rolled shells with flexible end disks and locking assemblies. Early pulley engineering was developed by Josef Sitzwohl in Australia in 1948 and later by Helmuth Lange and Walter Schmoltzi in Germany.\nComponents.\nPulleys are made up of several components including the shell, end disk, hub, shaft and locking assembly. The end disk and hub may be one piece. The locking assembly may also be replaced with a hub and bushing on lower tension pulleys. The shell is also referred to as the rim in some parts of the world.\nThe pulley shaft is typically sized following CEMA B105.1 in the Americas or AS 1403 in Australia.\nHistoric manufacturers.\nPulley manufacturers in East Germany (DDR) in 1962 included Zemag, Lauchhammer, and Köthen.", "Engineering,_Manufacturing": 1.0000078678, "qwen": "Yes"}
{"id": "45315373", "revid": "27199084", "url": "https://en.wikipedia.org/wiki?curid=45315373", "title": "KYB Corporation", "text": " is a Japanese, Tokyo-based automotive company.\nAmong KYB's main products company are shock absorbers, air suspensions, power steering systems, hydraulic pumps, motors, cylinders, and valves. It is one of the world's largest shock absorber manufacturers and it also has the largest market share of concrete mixer trucks in Japan, with 85% of the market.\nThe company has 34 manufacturing plants and 62 offices in 21 countries. KYB's American aftermarket distribution of automotive shocks and struts is headquartered in Greenwood, IN, with additional KYB manufacturing and distribution facilities in metro Chicago, Southern California, and metro Indianapolis. KYB Americas employs more than 100 people in all facilities. Shocks and struts for vehicles are the most popular KYB products distributed in North America.\nAircraft manufacturing.\nAircraft manufacturing during and after World War II.\nThe company between 1939 and 1941 developed several gliders, autogyros and research aircraft for the Imperial Japanese Army. These are:\nAfter the war, in 1954, the company built a gyrodyne, named Kayaba Heliplane. The development of this aircraft started in 1952 when Shiro Kayaba, the founder of the company, obtained the fuselage of a Cessna 170B and, over the course of two years, turned it into a convertiplane.", "Engineering,_Manufacturing": 0.9999102354, "qwen": "Yes"}
{"id": "23588776", "revid": "1156695243", "url": "https://en.wikipedia.org/wiki?curid=23588776", "title": "Active packaging", "text": "The terms active packaging, intelligent packaging, and smart packaging refer to amplified packaging systems used with foods, pharmaceuticals, and several other types of products. They help extend shelf life, monitor freshness, display information on quality, improve safety, and improve convenience.\nThe terms are often related and can overlap. \"Active packaging\" usually means having active functions beyond the inert \"passive\" containment and protection of the product. \"Intelligent\" and \"smart\" packaging usually involve the ability to sense or measure an attribute of the product, the inner atmosphere of the package, or the shipping environment. This information can be communicated to users or can trigger active packaging functions. Programmable matter, smart materials, etc. can be employed in packages. Yam, Tashitov, and Miltz have defined intelligent or smart packaging as: \nDepending on the working definitions, some traditional types of packaging might be considered as \"active\" or \"intelligent\". More often, the terms are used with new technologically advanced systems: microelectronics, computer applications, nanotechnology, etc.\nMoisture control.\nFor many years, desiccants have been used to control the water vapor in a closed package. A desiccant is a hygroscopic substance usually in a porous pouch or sachet which is placed inside a sealed package. They have been used to reduce corrosion of machinery and electronics and to extend the shelf life of moisture-sensitive foods. With pharmaceutical packages, a common method is to include a small packet of desiccant in a bottle. Other methods of including desiccants attached to the inner surface or in the material have recently been developed.\nCorrosion.\nCorrosion inhibitors can be applied to items to help prevent rust and corrosion. Volatile corrosion inhibitors (VCI) or vapor phase corrosion inhibitors can be provided inside a package in a pouch or can be incorporated in a saturated overwrap of special paper or plastic film. Many of these are organic salts that condense on the metal to resist corrosion. Some films also have VCI emitting capability.\nFilms are available with copper ions in the polymer structure, These neutralize the corrosive gas in a package and deter rust.\nVCIs create a neutral environment in the packaging. It works on the principle of difference in vapour pressure and causes reaction with metals and non-metals, and with moisture to prevent corrosion. There are different forms of VCIs available, such as papers, plastics, HDPE papers, oils, foams, chips, aluminum barrier foils, bubble, and emitters that can prevent corrosion at many stages.\nMetal chelation.\nTrace transition metals in foods, especially iron, can induce oxidative degradation of many food components, especially lipids, and cause quality changes of the products. Metal-chelating active packaging materials are made by immobilizing metal-chelating active compounds onto traditional active packaging material. The surface immobilized metal-chelating compounds can scavenge the transition metals from the product and enhance the oxidative stability of the product. The metal-chelating active packaging technology is also antioxidant active packaging that will extend the shelf-life of consumer products by controlling the oxidation. The metal-chelating active packaging technology is known to be able to remove synthetic food preservatives (e.g. EDTA) from the food product. This technology can be used to address the increasing consumer demand for additive free and 'clean' label food products.\nOxygen control.\nOxygen scavengers or oxygen absorbers help remove oxygen from a closed package. Some are small packets or sachets containing powdered iron: as the iron rusts, oxygen is removed from the surrounding atmosphere. Newer systems are on cards or can be built into package films or molded structures.\nIn addition, the physical characteristics of the packaging itself (oxygen transmission rate - OTR) can dictate how effective an oxygen absorber can be, and how long it will stay effective. Packaging with a low OTR will let less oxygen in the closed package through the polymer barrier itself.\nAtmosphere.\nWith some products, such as cheese, it has long been common to flush the package with nitrogen prior to sealing: the inert nitrogen is absorbed into the cheese, allowing a tight shrink film package. The nitrogen removes oxygen and interacts with the cheese to make the package functional.\nMore recently, other mixtures of gas have been used inside the package to extend the shelf life. The gas mixture depends on the specific product and its degradation mechanisms. Some package components have been developed that incorporate active chemistry to help maintain certain atmospheres in packages.\nOxygen scavengers, carbon dioxide generators, ethanol generators, etc. are available to help keep the atmosphere in a package at specified conditions.\nTemperature monitor.\nSome temperature indicators give a visual signal that a specified temperature has been exceeded. Others, Time temperature indicators, signal when a critical accumulation of temperature deviation over time has been exceeded. When the mechanism of the indicator is tuned to the mechanism of product degradation, these can provide valuable signals for consumers.\nDigital temperature data loggers record the temperatures encountered throughout the shipment. This data can be used to predict product degradation and help determine if the product is suited for normal sale or if expedited sale is required. They also determine the time of the temperature excess: this can be used to direct corrective action.\nThermochromic inks are sometimes used to signal temperature excess or change. Some are reversible while others have a permanent change of color. These can be used alone or with other packaging functions such as barcodes.\nThe inks can also signal a desired temperature for consumers. For example, one type of beer can has ink that graphically shows when an ideal drinking temperature is achieved.\nControlling package temperatures.\nFor critical vaccines, insulated shipping containers are passive packaging to help control the temperatures fluctuations seen even with a controlled cold chain. In addition, gel packs are often used to keep the temperature of the contents within specified acceptable temperature ranges.\nSome newer packages have the ability to heat or cool the product for the consumer. These have segregated compartments where exothermic or endothermic reactions provide the desired effect. Self-heating food packaging is available for several products.\nDispensing.\nSome packages have closures or other dispensing systems that change the contents from a liquid to an aerosol. These are used for products ranging from precision inhalers for medications to spray bottles of household cleaners.\nSome dispensing packages for two-part epoxy adhesives do more than passively contain the two components. When dispensed, some packages meter and mix the two components so the adhesive is fully functioning at the point of application.\nThe ability of a package to fully empty or dispense a viscous liquid is somewhat dependent on the surface energy of the inner walls of the container. The use of superhydrophobic surfaces is useful but can be further improved by using new lubricant-impregnated surfaces.\nRFID.\nRadio-frequency identification chips are becoming more common with the introduction of smart labels that are used to track and trace packages and unit loads throughout distribution. Newer developments include recording the temperature history of shipments and other intelligent packaging functions.\nRFID can be integrated into labels: Smart labels.\nSecurity.\nA variety of security printing methods, security holograms, and specialized labels are available to help confirm that the product in the package is not counterfeit. RFID chips are being used in this application also.\nElectronic article surveillance (on the product or on the package) is used to help counter shoplifting.\nMicrowave packaging.\nMetallised films are used as a susceptor for cooking in microwave ovens. These increase the heating capacity and help make foods crisp and brown. Plastic microwavable containers are also used for microwave cooking.\nShock and vibration.\nShock detectors have been available for many years. These are attached to the package or to the product in the package to determine if an excessive shock has been encountered. The mechanisms of these \"shock overload\" devices have been spring-mass systems, magnets, drops of red dye, and several others.\nRecently, digital shock and vibration data loggers have been available to more accurately record the shocks and vibrations of shipment. These are used to monitor critical shipments to determine if extra inspection and calibration is required. They are also used to monitor the types of shocks and vibrations encountered in transit for use in package testing in a laboratory.\nAntimicrobial control.\nSome engineered packaging films contain enzymes, antimicrobial agents, scavengers, natural pigments and other active components to help control food degradation and extend shelf life and safety. \nThe mechanism focuses on preventing the growth of pathogenic or spoilage microorganisms.\nBar Codes.\nBar codes have long been used with packaging to identify an item, facilitate routing, communicate locations, etc. there are many varietuies of linear bar codes. Some are stacked to provide more information. Two dimensional Matrix codes can have a higher information density. \nQR Codes can be used on packaging to provide additional information on the product via a smartphone scan. With digital printers, unit-level QR Codes can become the equivalent of a unique identifier or URL for each packaging, and enable other interactions with consumers such as providing specific information on product traceability, or deploying loyalty programs. Unit-level QR Codes are easy to counterfeit if additional security features are not used, but the scan data generated can be used for active brand protection. A digital watermark or secure graphic can be inserted into the QR Code to make it copy-sensitive and let consumers authenticate products with a higher security level.\nThe GS1 digital link is a standard for embedding GS1 standardised product identifiers into the unique identifier, which allows the same QR Code (or other data carrier) to provide information to consumers, retailers and supply chain.\nPrinted codes can be combined with security printing for expanded uses. For example thermochromic ink can be used to activate, change, or deactivate a code based on the item’s temperature history.\nOther developments.\nEdible films have been developed to allow consumers to eat the package along with the product.\nPackaging materials including silver nanoparticles have been shown to extend the shelflife of some foods.\nSpecial packaging has been developed for shipping organs which keeps them alive during extended shipments. The organs are alive and fresh for transplanting.\nSeveral packages used by Canadian cannabis corporations use active packaging to monitor THC levels throughout the production process. This is being implemented in order to ensure consistency between products to improve supply chain management as well as offer consumers improved value of purchase.\nRegulations.\nActive packaging is often designed to interact with the contents of the package. Thus extra care is often needed for active or smart packagings that are food contact materials.\nFood packagers take extra care with some types of active packaging. For example, when the oxygen atmosphere in a package is reduced for extending shelf life, controls for anaerobic bacteria need to be considered. Also when a controlled atmosphere reduces the appearance of food degradation, consumers need to retain a means of determining whether actual degradation is present.", "Engineering,_Manufacturing": 0.9999642372, "qwen": "Yes"}
{"id": "23608428", "revid": "43732327", "url": "https://en.wikipedia.org/wiki?curid=23608428", "title": "Electron-beam freeform fabrication", "text": "Electron-beam freeform fabrication (EBF3) is an additive manufacturing process that builds near-net-shape parts. It requires far less raw material and finish machining than traditional manufacturing methods. EBF3 is done in a vacuum chamber where an electron beam is focused on a constantly feeding source of metal, which is melted and applied as called for by a three-dimensional layered drawing - one layer at a time - on top of a rotating metallic substrate until the part is complete.\nHistory.\nThe use of electron beam welding for additive manufacturing was first developed by Vivek Davee in 1995 as part of his PhD thesis at MIT. The process was referred to as electron beam solid freeform fabrication (EBSFF). A team at NASA Langley Research Center (LaRC) led by Karen Taminger developed the process, calling it electron beam freeform fabrication (EBF3). EBF3 is a NASA-patented additive manufacturing process designed to build near-net-shape parts requiring less raw material and finish machining than traditional manufacturing methods. EBF3 is a process by which NASA plans to build metal parts in zero-gravity environments; this layer-additive process uses an electron beam and a solid wire feedstocks to fabricate metallic parts. Future astronauts stationed on the Moon or Mars may be able to employ EBF3 to produce replacement parts locally rather than relying on parts launched from Earth, possibly even mining feedstock from the surrounding soils. The aviation industry has the most potential for the procedure, say experts at the NASA LaRC, because there should be significant progress made in reducing machining waste byproducts. Typically, an aircraft maker would start with a 6,000-pound block of titanium and use thousands of litres of cutting fluid to reduce it to a 300-pound item, leaving 5,700 pounds of material that needed to be recycled. According to Taminger, \"With EBF3 you can build up the same part using only 350 pounds of titanium and machine away just 50 pounds to get the part into its final configuration. And the EBF3 process uses much less electricity to create the same part.\"\nProcess.\nThe operational concept of EBF3 is to build a near-net-shape metal part directly from a computer-aided design (CAD) file. Current computer-aided machining practices start with a CAD model and use a post-processor to write the machining instructions (G-code) defining the cutting tool paths needed to make the part. EBF3 uses a similar process, starting with a CAD model, numerically reducing it into layers, then using a post-processor to write the G-code defining the deposition path and process parameters for the EBF3 equipment. It uses a focused electron beam in a vacuum environment to create a molten pool on a metallic substrate. The beam is translated by the surface of the substrate while the metal wire is fed into the molten pool. The deposit solidifies immediately after the electron beam has passed, having sufficient structural strength to support itself. The sequence is repeated in a layer-additive manner to produce a near-net-shape part needing only finish machining. The EBF3 process is scalable for components from fractions of an inch to tens of feet in size, limited mainly by the size of the vacuum chamber and the amount of wire feedstock available.", "Engineering,_Manufacturing": 1.0000021458, "qwen": "Yes"}
{"id": "52032623", "revid": "43558034", "url": "https://en.wikipedia.org/wiki?curid=52032623", "title": "Agile tooling", "text": "Agile tooling is the design and fabrication of manufacturing related-tools such as dies, molds, patterns, jigs and fixtures in a configuration that aims to maximise the tools' performance, minimise manufacturing time and cost, and avoid delay in prototyping. A fully functional agile tooling laboratory consists of CNC milling, turning and routing equipment. It can also include additive manufacturing platforms (such as fused filament fabrication, selective laser sintering, Stereolithography, and direct metal laser sintering), hydroforming, vacuum forming, die casting, stamping, injection molding and welding equipment.\nAgile tooling is similar to rapid tooling, which uses additive manufacturing to make tools or tooling quickly, either directly by making parts that serve as the actual tools or tooling components, such as mold inserts; or indirectly by producing patterns that are in turn used in a secondary process to produce the actual tools. Another similar technique is prototype tooling, where molds, dies and other devices are used to produce prototypes. Rapid manufacturing, and specifically rapid tooling technologies, are earlier in their development than rapid prototyping (RP) technologies, and are often extensions of RP.\nThe aim of all toolmaking is to catch design errors early in the design process; improve product design better products, reduce product cost, and reduce time to market.\nUsers.\nHundreds of universities and research centers around the globe are investing in additive manufacturing equipment in order to be positioned to make prototypes and tactile representations of real parts. Few have fully committed the concept of using additive manufacturing (AM) to create manufacturing tools (fixturing, clamps, molds, dies, patterns, negatives, etc.). AM experts seem to agree that tooling is a large, namely untapped market. Deloitte University Press estimated that in 2012 alone, the AM Tooling market $1.2 Billion. At that point in the development cycle of AM Tooling, much of the work was performed under the guise of “let’s try it and see what happens”.\nIndustry applications.\nAdditive manufacturing, starting with today's infancy period, requires manufacturing firms to be flexible, ever-improving users of all available technologies to remain competitive. Advocates of additive manufacturing also predict that this arc of technological development will counter globalization, as end users will do much of their own manufacturing rather than engage in trade to buy products from other people and corporations. The real integration of the newer additive technologies into commercial production, however, is more a matter of complementing traditional subtractive methods rather than displacing them entirely.\nAutomotive – approaching niche vehicle markets (making less than 100, 000 vehicles), rather than high production volume\nAircraft – the U.S. aircraft industry operates in an environment where production volumes are relatively low and resulting product costs are relatively high. Agile tooling can be applied in the early design stage of the development cycle to minimize the high cost of redesign.\nMedical – cast tooling would benefit a great deal from agile tooling. However, the cost for the tooling may still be significantly greater than the cost of a casting piece, with high lead times. Since only several dozen or several hundred metal parts are needed, the challenge for mass production is still prevalent. A balance between these four areas – quantity, design, material, and speed are key to designing and producing a fully functional product.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "18668281", "revid": "1170296995", "url": "https://en.wikipedia.org/wiki?curid=18668281", "title": "Dowelmax", "text": "The Dowelmax is a loose tenon dowelling jig manufactured by the O.M.S. Tool company in Canada. The manufacturer claims that the small manufacturing tolerances of for the aluminium, brass and steel components of the jig ensure accuracy and repeatability. The precision manufacturing adds to the unit's cost, which is higher than other dowelling jigs.\nThe tool allows the placement of five dowels in one pass. A distance gauge bar provided with the jig allows accurate spacing between sets of dowels.\nJoint strength.\nTests by both the manufacturer, and Wood magazine, are claimed to show that dowel joints made with the Dowelmax are stronger than most other woodworking joints tested.\nIn 2007, \"Wood\" magazine compared the joint strength of various loose tenon methods and tools, with these results:\nA 2011 review by Wood Magazine, has rated Dowelmax very highly as a dowel joinery tool. The review classifies Dowelmax as \"the best dowelling jig ever made\".", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "9515578", "revid": "27619473", "url": "https://en.wikipedia.org/wiki?curid=9515578", "title": "Cellular manufacturing", "text": "Cellular manufacturing is a process of manufacturing which is a subsection of just-in-time manufacturing and lean manufacturing encompassing group technology. The goal of cellular manufacturing is to move as quickly as possible, make a wide variety of similar products, while making as little waste as possible. Cellular manufacturing involves the use of multiple \"cells\" in an assembly line fashion. Each of these cells is composed of one or multiple different machines which accomplish a certain task. The product moves from one cell to the next, each station completing part of the manufacturing process. Often the cells are arranged in a \"U-shape\" design because this allows for the overseer to move less and have the ability to more readily watch over the entire process. One of the biggest advantages of cellular manufacturing is the amount of flexibility that it has. Since most of the machines are automatic, simple changes can be made very rapidly. This allows for a variety of scaling for a product, minor changes to the overall design, and in extreme cases, entirely changing the overall design. These changes, although tedious, can be accomplished extremely quickly and precisely.\nA cell is created by consolidating the processes required to create a specific output, such as a part or a set of instructions. These cells allow for the reduction of extraneous steps in the process of creating the specific output, and facilitate quick identification of problems and encourage communication of employees within the cell in order to resolve issues that arise quickly. Once implemented, cellular manufacturing has been said to \"reliably\" create massive gains in productivity and quality while simultaneously reducing the amount of inventory, space and lead time required to create a product. It is for this reason that the one-piece-flow cell has been called \"the ultimate in lean production.\"\nHistory.\nCellular manufacturing is derivative of principles of group technology, which were proposed by Flanders in 1925 and adopted in Russia by Mitrofanov in 1933 (whose book was translated into English in 1959). Burbidge actively promoted group technology in the 1970s. \"Apparently, Japanese firms began implementing cellular manufacturing sometime in the 1970s,\" and in the 1980s cells migrated to the United States as an element of just-in-time (JIT) production.\nOne of the first English-language books to discuss cellular manufacturing, that of Hall in 1983, referred to a cell as a “U-line,” for the common, or ideal, U-shaped configuration of a cell—ideal because that shape puts all cell processes and operatives into a cluster, affording high visibility and contact. By 1990 cells had come to be treated as foundation practices in JIT manufacturing, so much so that Harmon and Peterson, in their book, \"Reinventing the Factory\", included a section entitled, \"Cell: Fundamental Factory of the Future\". Cellular manufacturing was carried forward in the 1990s, when just-in-time was renamed lean manufacturing. Finally, when JIT/lean became widely attractive in the service sector, cellular concepts found their way into that realm; for example, Hyer and Wemmerlöv's final chapter is devoted to office cells.\nCell design.\nCells are created in a workplace to facilitate flow. This is accomplished by bringing together operations or machines or people involved in a processing sequence of a products natural flow and grouping them close to one another, distinct from other groups. This grouping is called a cell. These cells are used to improve many factors in a manufacturing setting by allowing \"one-piece flow\" to occur. An example of one-piece flow would be in the production of a metallic case part that arrives at the factory from the vendor in separate pieces, requiring assembly. First, the pieces would be moved from storage to the cell, where they would be welded together, then polished, then coated, and finally packaged. All of these steps would be completed in a single cell, so as to minimize various factors (called non-value-added processes/steps) such as time required to transport materials between steps. Some common formats of single cells are: the U-shape (good for communication and quick movement of workers), the straight line, or the L-shape. The number of workers inside these formations depend on current demand and can be modulated to increase or decrease production. For example, if a cell is normally occupied by two workers and demand is doubled, four workers should be placed in the cell. Similarly, if demand halves, one worker will occupy the cell. Since cells have a variety of differing equipment, it is therefore a requirement that any employee is skilled at multiple processes.\nWhile there exist many advantages to forming cells, there are some obvious benefits. It is quickly evident from observation of cells where inefficiencies lie, such as when an employee is too busy or relatively inactive. Resolving these inefficiencies can increase production and productivity by up to and above 100% in many cases. In addition to this, formation of cells consistently frees up floor space in the manufacturing/assembly environment (by having inventory only where it is absolutely required), improves safety in the work environment (due to smaller quantities of product/inventory being handled), improves morale (by imparting feelings of accomplishment and satisfaction in employees), reduces cost of inventory, and reducing inventory obsolescence.\nWhen formation of a cell would be too difficult, a simple principle is applied in order to improve efficiencies and flow, that is, to perform processes in a specific location and gather materials to that point at a rate dictated by an average of customer demand (this rate is called the \"takt\" time). This is referred to as the Pacemaker Process.\nDespite the advantages of designing for one-piece-flow, the formation of a cell must be carefully considered before implementation. Use of costly and complex equipment that tends to break down can cause massive delays in the production and will ruin output until they can be brought back online.\nThe short travel distances within cells serve to quicken the flows. Moreover, the compactness of a cell minimizes space that might allow build-ups of inventory between cell stations. To formalize that advantage, cells often have designed-in rules or physical devices that limit the amount of inventory between stations. Such a rule is known, in JIT/lean parlance, as kanban (from the Japanese), which establishes a maximum number of units allowable between a providing and a using work station. (Discussion and illustrations of cells in combinations with kanban are found in) The simplest form, kanban squares, are marked areas on floors or tables between work stations. The rule, applied to the producing station: \"If all squares are full, stop. If not, fill them up.\"\nAn office cell applies the same ideas: clusters of broadly trained cell-team members that, in concert, quickly handle all of the processing for a family of services or customers.\nA virtual cell is a variation in which all cell resources are not brought together in a physical space. In a virtual cell, as in the standard model, team members and their equipment are dedicated to a family of products or services. Although people and equipment are physically dispersed, as in a job shop, their narrow product focus aims for and achieves quick throughput, with all its advantages, just as if the equipment were moved into a cellular cluster. Lacking the visibility of physical cells, virtual cells may employ the discipline of kanban rules in order to tightly link the flows from process to process.\nA simple but rather complete description of cell implementation comes from a 1985 booklet of 96 pages by Kone Corp. in Finland, producer of elevators, escalators, and the like. Excerpts follow: \nImplementation process.\nIn order to implement cellular manufacturing, a number of steps must be performed. First, the parts to be made must be grouped by similarity (in design or manufacturing requirements) into families. Then a systematic analysis of each family must be performed; typically in the form of production flow analysis (PFA) for manufacturing families, or in the examination of design/product data for design families. This analysis can be time-consuming and costly, but is important because a cell needs to be created for each family of parts. Clustering of machines and parts is one of the most popular production flow analysis methods. The algorithms for machine part grouping include Rank Order Clustering, Modified Rank Order Clustering, and Similarity coefficients.\nThere are also a number of mathematical models and algorithms to aid in planning a cellular manufacturing center, which take into account a variety of important variables such as, \"multiple plant locations, multi-market allocations with production planning and various part mix.\" Once these variables are determined with a given level of uncertainty, optimizations can be performed to minimize factors such as, \"total cost of holding, inter-cell material handling, external transportation, fixed cost for producing each part in each plant, machine and labor salaries.\"\nDifficulties in creating flow.\nThe key to creating flow is continuous improvement to production processes. Upon implementation of cellular manufacturing, management commonly \"encounters strong resistance from production workers\". It will be beneficial to allow the change to cellular manufacturing to happen gradually. In this process.\nIt is also difficult to fight the desire to have some inventory on hand. It is tempting, since it would be easier to recover from an employee suddenly having to take sick leave. Unfortunately, in cellular manufacturing, it is important to remember the main tenets: \"You sink or swim together as a unit\" and that \"Inventory hides problems and inefficiencies.\" If the problems are not identified and subsequently resolved, the process will not improve.\nAnother common set of problems stems from the need to transfer materials between operations. These problems include, \"exceptional elements, number of voids, machine distances, bottleneck machines and parts, machine location and relocation, part routing, cell load variation, inter and intracellular material transferring, cell reconfiguring, dynamic part demands, and operation and completion times.\" These difficulties need to be considered and addressed to create efficient flow in cellular manufacturing.\nBenefits and costs.\nCellular manufacturing brings scattered processes together to form short, focused paths in concentrated physical space. So constructed, by logic a cell reduces flow time, flow distance, floor space, inventory, handling, scheduling transactions, and scrap and rework (the latter because of quick discovery of nonconformities). Moreover, cells lead to simplified, higher validity costing, since the costs of producing items are contained within the cell rather than scattered in distance and the passage of reporting time.\nCellular manufacturing facilitates both production and quality control. Cells that are underperforming in either volume or quality can be easily isolated and targeted for improvement. The segmentation of the production process allows problems to be easily located and it is more clear which parts are affected by the problem.\nThere are also a number of benefits for employees working in cellular manufacturing. The small cell structure improves group cohesiveness and scales the manufacturing process down to a more manageable level for the workers. Workers can more easily see problems or possible improvements within their own cells and tend to be more self-motivated to propose changes. Additionally, these improvements that are instigated by the workers themselves cause less and less need for management, so over time overhead costs can be reduced. Furthermore, the workers often are able to rotate between tasks within their cell, which offers variety in their work. This can further increase efficiency because work monotony has been linked to absenteeism and reduced production quality.\nCase studies in just-in-time and lean manufacturing are replete with impressive quantitative measures along those lines. For example, BAE Systems, Platform Solutions (Fort Wayne, Ind.), producing aircraft engine monitors and controls, implemented cells for 80 percent of production, reducing customer lead time 90 percent, work-in-process inventory 70 percent, space for one product family from 6,000 square feet to 1,200 square feet, while increasing product reliability 300 percent, multi-skilling the union-shop work force, and being designated an \"Industry Week\" Best Plant for the year 2000. By five years later, rework and scrap had been cut 50 percent, new product introduction cycles 60 percent, and transactions 90 percent, while also increasing inventory turns three-fold and service turn times 30 percent, and being awarded a Shingo Prize for the year 2005.\nIt appears to be difficult to isolate how much of those benefits accrue from cellular organization itself; among many case studies researched for this article few include attempts at isolating the benefits. One exception is the contention, at Steward, Inc. (Chattanooga, Tenn.), producing nickel zinc ferrite parts for electromagnetic interference suppression. According to case study authors, cells resulted in reductions of cycle time from 14 to 2 days, work-in-process inventories by 80 percent, finished inventories by 60 percent, lateness by 96 percent, and space by 56 percent.\nAnother cellular case study includes quantitative estimates of the extent to which cells contributed to overall benefits. At Hughes Ground Systems Group (Fullerton, Calif.), producing circuit cards for defense equipment, the first cell, which began as a pilot project with 15 volunteers, was launched in 1987. One month later a second cell began, and by 1992 all production employees, numbering about 150, had been integrated into seven cells. Prior to cells, circuit card cycle time, from kit release to shipment to the customer, had been 38 weeks. After the cells had taken over the full production sequence (mechanical assembly, wave solder, thermal cycle, and conformal coat), cycle time had fallen to 30.5 weeks, of which production manager John Reiss attributed 20 weeks to use of a \"WIP chart system\" by the cell teams and the other 10.5 weeks to the cellular organization itself. Later, when it seemed that the cells were overly large and cumbersome, cell sizes were shrunk by two-thirds, resulting in “micro cells” that cut cycle time by another 1.5 weeks. Finally, by adopting certain other improvements, cycle times had decreased to four weeks. Other improvements included reducing work-in-process inventory from 6 or 7 days to one day and percent defective from 0.04 to 0.01 Switching from a functional (job-shop) layout to cells often costs has a minus net cost, inasmuch as the cell reduces costs of transport, work-in-process and finished inventory, transactions, and rework. When large, heavy, expensive pieces of equipment (sometimes called “monuments” in lean lingo) must be moved, however, the initial costs can be high to the point where cells are not feasible.\nThere are a number of possible limitations to implementing cellular manufacturing. Some argue that cellular manufacturing can lead to a decrease in production flexibility. Cells are typically designed to maintain a specific flow volume of parts being produced. Should the demand or necessary quantity decrease, the cells may have to be realigned to match the new requirements, which is a costly operation, and one not typically required in other manufacturing setups.", "Engineering,_Manufacturing": 1.0000058413, "qwen": "Yes"}
{"id": "20881584", "revid": "34029739", "url": "https://en.wikipedia.org/wiki?curid=20881584", "title": "Beverage opener", "text": "A beverage opener (also known as a multi-opener) is a device used to open beverage cans, plastic bottles or glass bottles, which are the three most common beverage containers.\nTypes.\nBeverage openers vary in size but commonly include a glass bottle crown cork remover, glass bottle threaded metal crown cork cap grip for greater twisting torque, a plastic bottle cap grip for greater twisting torque and a stay tab lever for metal beverage cans. Some openers have extra conveniences built in such as magnetic backing to catch and hold metal caps or stick to a refrigerator door. They may be standalone devices are incorporated into can openers.\nBenefits.\nBeverage openers are useful for opening every day beverage containers for those who have limited hand strength as it eliminates the need for strong twisting or pulling motions. Plastic bottles may become stuck due to a high volume of carbonation released during shipping or overtightening. Some do not have fingernails with which to properly use a stay tab and glass bottles almost always require some sort of bottle opener.", "Engineering,_Manufacturing": 0.9999138117, "qwen": "Yes"}
{"id": "18151097", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=18151097", "title": "Humanitarian logistics", "text": "Although logistics has been mostly utilized in commercial supply chains, it is also an important tool in disaster relief operations. Humanitarian logistics is a branch of logistics which specializes in organizing the delivery and warehousing of supplies during natural disasters or complex emergencies to the affected area and people. However, this definition focuses only on the physical flow of goods to final destinations, and in reality, humanitarian logistics is far more complicated and includes forecasting and optimizing resources, managing inventory, and exchanging information. Thus, a good broader definition of humanitarian logistics is the process of planning, implementing and controlling the efficient, cost-effective flow and storage of goods and materials, as well as related information, from the point of origin to the point of consumption for the purpose of alleviating the suffering of vulnerable people.\nThis figure presents numerous important aspects in humanitarian logistics, including transport, inventory management, infrastructure, and communications.\nThe role of humanitarian logistics in disaster relief efforts.\nHumanitarian logistics plays an integral role in disaster relief for several reasons. First, humanitarian logistics contributes immensely to mitigating the negative impact of natural disasters in terms of loss of life and economic costs. These losses occur in four different ways:\nSecond, humanitarian logistics is considered the repository of data that can be analyzed to provide post-event learning. Logistics data reflects all aspects, from the effectiveness of suppliers and transportation providers, to the cost and timeliness of response, to the appropriateness of donated goods and the management of information. Thus, it is critical to the performance of both current and future operations and programs. Organizing emergency response plans will help preparation and consequently mobilization in times of disasters.\nThe process of humanitarian logistics.\nAs can be seen in the above Figure, the process is complicated with the involvement of various actors in different locations. To be more specific, the process connects various actors, including, donors, local/international aid organizations, local governments, and beneficiaries. There are three fundamental flows in this process: the flow of material, the flow of money, and the flow of information.\nStorage.\nDeveloping logistics warehousing to store all essential goods plays a crucial role in disaster response planning. Warehouses should be designed by taking precautions for contamination or waste of materials and organized in order to facilitate deliveries to the desired area at the desired time and quantities. In addition, responsible authorities aim at maximizing responsiveness and minimizing distribution times, total costs, and the number of distribution centers. The entire storage process is of key importance for preserving emergency supplies until they can be delivered to recipients.\nTypes of warehouse.\nHumanitarian Warehouses can be categorized into four main types, depending on their functions and locations.\nHumanitarian Warehouses can also be classified as perishables warehouses or 3PL warehouses. However, it is common in humanitarian logistics to have four types of warehouses as mentioned above. Depending on the magnitude of disasters and the urgency, a certain type of warehouses is needed. For example, for unexpected disasters, temporary warehouses are more common than others. In contrast, for planned disasters, general delivery warehouses are needed to store products in beneficiary countries.\nChoices of warehouses.\nWhen selecting an appropriate site to store goods, two considerations are important:\nInventory management.\nA logistical technique which can improve responsiveness is inventory pre-positioning. This technique is used for estimating item quantities required according to specific safety stock levels and order frequency, or for searching optimal locations for warehouses using facility location. Logistics is one of the major tools of disaster preparedness, among surveillance, rehearsal, warning, and hazard analysis. There are four primary types of inventory planning:\nEach model has different advantages and disadvantages; therefore, it is important for inventory planners to consider all aspects, including total holding costs, service level, and demand variability, to have an efficient strategy.\nTransport.\nTransport plays a key role in mobilizing supplies to help emergency humanitarian assistance reach affected regions. In humanitarian logistics, it is important to determine the feasibility of various forms of transport on the basis of the level of urgency, total costs, and geographical characteristics of affected zones.\nConsiderations of different means of transport.\nWhen planning the type and capacity of transport, five major considerations are crucial:\nThe below table provides a simple formula to help planners forecast transport demand during a disaster. There are three main components: the number of trips for a vehicle, the volume, and the total number of vehicles.\nTypes of transport contracts.\nThere are three primary types of transport contracts. Each type has distinct advantages and disadvantages.\nNew technologies in humanitarian logistics.\nTechnology is a key factor to achieve better results in disaster logistics. Setting up a communication mechanism in geographies that are remote and devoid of internet or phone networks, implementing up-to-date information or tracking systems & using humanitarian logistics software which can provide real-time supply chain information, organizations can enhance decision making, increase the quickness of the relief operations and achieve better coordination of the relief effort. Biometrics for identifying persons or unauthorized substances, wireless telecommunications, media technology for promoting donations, and medical technologies are some more aspects of technology applied in humanitarian operations. There are four main developments in this field: bar codes, AMS laser cards, radio frequency tags & satellite based internet services.\nAMS Cards.\nAutomated manifest system (AMS) cards have been used by the United States government to store substantial amounts of information about shipments. The cards have become more popular in humanitarian logistics as they are able to provide various aspects related to:\nThe AMS cards are attached to both pallets and containers and inserted to a processing unit which can give all details about a delivery. The use of those cards is beneficial to both shippers and beneficiaries in humanitarian logistics management because beneficiaries can plan resources, especially food and medicines, or find alternatives. Therefore, this application can make the process more flexible and efficient. In addition, AMS cards are cheap, reusable, and resistant to extreme weather.\nRadio Frequency Identification Tags and Labels.\nThe tags are useful in identifying information about delivery routes. They are attached to different types of vehicles, including pallets, trucks, vans, and large containers, to position the location of shipments en route. In addition, they can read information when the vehicles pass through points along the route. After that, the information is stored on a label. Together with the AMS cards, they can provide an effective solution to humanitarian logistics to increase its transparency and responsiveness.\nBar Codes.\nOne major concern in humanitarian logistics management is the reliability of product sources because the most popularly-procured item is food. In the past, there were cases regarding food unsafety caused by the unclear origins of products. Recently, bar codes have been a feasible solution to address this problem in humanitarian logistics. Bar code labels make it possible to represent alphanumeric characters (letters and numbers) by means of bars and blanks of varying widths that can be read automatically by optical scanners. This system recognizes and processes these symbols, compares their patterns with those already stored in computer memory, and interpret the information. This standardized coding system means that there can be a one-on-one, unique, non-ambiguous relationship between the pattern and that to which it refers. At present, bar codes are mostly used in:\nSatellite based internet services.\nCommunication, especially in the remote disaster zones is often difficult due to absence or damage to the mobile communication networks. During the war in Ukraine in 2022, Starlink (Satellite internet) services opened a new possibility to restore this vital service capability.\nEnvironmental impact of humanitarian logistics.\nWhile the primary goal of humanitarian logistics is saving lives, their environmental impact has been a source of concern. Adverse environmental impact can emanate from all the operations throughout the humanitarian supply chain including procurement, transportation, warehousing, delivery, and material waste. Compared to commercial supply chains, addressing environmental issues is more challenging in humanitarian logistics due to volatile context and absence of basic infrastructure such as recycling facilities. However, several humanitarian organizations such as International Committee of Red Cross (ICRC) have recently started to incorporate sustainability in their long-term strategy. Use of digital technologies have shown to provide humanitarian organizations with more visibility across their supply chain and thus lead to more environmentally sustainable supply chains.", "Engineering,_Manufacturing": 0.9958730936, "qwen": "Yes"}
{"id": "18159068", "revid": "44798997", "url": "https://en.wikipedia.org/wiki?curid=18159068", "title": "Advanced manufacturing", "text": "Advanced manufacturing is the use of innovative technology to improve products or processes, with the relevant technology being described as advanced, innovative or cutting edge. Advanced manufacturing industries increasingly integrate new innovative technologies in both products and processes. The rate of technology adoption and the ability to use that technology to remain competitive and add value to define the advanced manufacturing sector. \n\"World class manufacturing\" (WCM) integrates the latest-generation machinery with process/work systems to facilitate manufacturing based business development governed around manufactured products only, duly based over a high accent on product substitution or new product development.\nAdvanced manufacturing centers upon improving the performance of US industry through the innovative application of technologies, processes and methods to product design and production. A survey done in 2010 by White House defined advanced manufacturing and stated that:: \"A concise definition of advanced manufacturing offered by some is manufacturing that entails the rapid transfer of science and technology (S&T) into manufacturing products and processes.\" (PCAST, April 2010.)\nProduct technologies.\nOrganizations practicing advanced manufacturing make products characterized as:\nProcess technologies.\nThe manufacturing process technologies described in definitions of advanced manufacturing include:\nUse of business/management methodologies.\nA number of organizations also included business or management methodologies in their definition of advanced manufacturing. For example, one organization defines \"advanced manufacturing as the insertion of new technology, improved processes, and management methods to improve the manufacturing of products.\" (National Defense University, 2002, as reported in PCAST) Another organization lists advanced manufacturing as \"encompassing lean production techniques, enhanced supply chain integration, and technology assimilation\". In fact, the Wikipedia definition of advanced manufacturing is \"advanced planning and scheduling\" described as \"a manufacturing management process by which raw materials and production capacity are optimally allocated to meet demand\". Overall, the following business or management methodologies were listed as being a part of advanced manufacturing:\nOther definitions.\nThere are also definitions of \"advanced manufacturing\" that are used by one or a few sources.\nTraditional vs. advanced manufacturers.\nTraditional manufacturing is defined as the act of converting raw materials into finished products by using manual or mechanized transformational techniques. The purpose of such activities is to add value to achieve targeted objectives, which do not preclude society's overall interests. In one report, the distinction between traditional sectors of manufacturing (listed as auto, steel) and others (listed as aerospace, medical device, pharmaceutical) is the basis for a definition of advanced manufacturing, with the characteristics of the two differing in terms of volume and scale economies, labor and skill content, and the depth and diversity of the network surrounding the industry (New England Council and Deloitte, as referenced in PCAST document).\nSuccessful manufacturers.\nOther sources define advanced manufacturers as those that \"succeed\" in today's competitive environment. One source states that: \"What differentiates certain companies is a unique ability to create a competitive advantage in this environment. These manufacturers think and do faster and, by definition, these advantages make them advanced.\" (Industrial College of the Armed Forces) The White House survey lists some experts as defining advanced manufacturing \"solely by advances that led to decreased cost or increased productivity.\" (PCAST)\nResearch and development.\nOne organization listed \"aggressive research and development\" as being part of the definition of advanced manufacturing (Purdue University). Although research and development were not explicitly included in most definitions, the innovative technologies listed by many are most likely the result of extensive research and development. Development of a sound product, which satisfies given criteria with least pain, is a common challenge, most unusually, haunting the manufacturer. The domain of competition is quite large because manufacturers compete at inter-manufacturing and intra-firm levels, producing near net products. The customer desires a component which promises functions most reliably, while addressing socio-techno-environmental attributes.\nDynamic.\nFinally, several sources pointed out that any definition of advanced manufacturing will need to change with the changing times, and that the definition will vary for different companies and different industries. The White House survey states: \"Most discussants agree that an appropriate advanced manufacturing definition should be dynamic in nature and be treated as more of a benchmark\". That is, there is a constant iteration of improving manufacturing frontiers. Therefore, what is classified as \"frontier\" is constantly changing and likewise, advanced manufacturing is constantly changing. (PCAST) Another source stated that: \"Advanced manufacturing is like a chameleon\". It changes in response to the needs of whichever company has incorporated it into its manufacturing process (St. Louis, C.B. Adams). An expert is quoted as saying: \"Advanced manufacturing, by its very nature, defies definition, because it is going to be different for the chemical industry than it is for the metal fabrication industry and any other industry \" (Tom White, as quoted by C.B. Adams).\nConclusion.\nThe term \"advanced manufacturing\" encompasses many of the developments in the manufacturing field during the late 20th and early 21st centuries, including high tech products and processes and clean, green, and flexible manufacturing, among others. No one definition captures everything said about advanced manufacturing, although the majority of definitions found on the web include the use of innovative technology to improve products and/or processes, and may also include the use of new business/management methodologies. Accordingly, the definition that probably comes closest to being comprehensive is that given by Paul Fowler of the National Council for Advanced Manufacturing (NACFAM), celebrating its 20th anniversary this year:\n\"The Advanced Manufacturing entity makes extensive use of computer, high precision, and information technologies integrated with a high-performance workforce in a production system capable of furnishing a heterogeneous mix of products in small or large volumes with both the efficiency of mass production and the flexibility of custom manufacturing in order to respond quickly to customer demands \" (Quoted in PCAST). In foreseeable future categorical developments facilitated with integration with computers will be largely impacted by the state of raw material and energy availability.", "Engineering,_Manufacturing": 1.0000047684, "qwen": "Yes"}
{"id": "18163177", "revid": "237572", "url": "https://en.wikipedia.org/wiki?curid=18163177", "title": "Direct injection expanded foam molding", "text": "Direct injection expanded foam molding (also known as \"injection molded foam\") is a manufacturing process that creates soft foam products direct from a compound into a final product. This process eliminates the steps normally required for die-cutting and compression molding, because it manufactures the foam and the product, simultaneously.\nThe base resin, used in a complex formula, is an ethylene-based polyolefin elastomer (like polyethylene and EVA). Foam that is manufactured with these resins has many physical benefits. Unlike a sponge, foams from this process are closed-cell, meaning it's waterproof and resists mold, mildew, and bacteria from entering the material.\nIt is also cross-linked, which means that the cells are connected in a way that makes the foam strong and durable with high tear and tensile strength.\nAll polyolefin elastomers are also resistant to most chemicals, which allows the products to not only be used in a chemical environment but also with most household cleaners.\nThe process itself is known to be very interesting because the injected compound is not foam, until an endothermic reaction in a hot mold activates the blowing agents, resulting in an expanded foam part. This requires the mold cavity size to be smaller than the final part. The actual known expansion is created within the formula, so that when the part \"self-ejects\" from the mold at the end of the cycle, it grows to the required part size.\nThe cavity for a tire is considerably smaller than the final tire size. This process is valuable for any foam product that needs to have lots of detail. It needs to be very durable.", "Engineering,_Manufacturing": 0.9994856715, "qwen": "Yes"}
{"id": "65496623", "revid": "1031418930", "url": "https://en.wikipedia.org/wiki?curid=65496623", "title": "Truck Bed Rack", "text": "A bed rack is usually a set of steel or aluminum bars secured to the body of a truck bed. Due to the tall tubes, aka legs, the bed rack is usually higher than the bed itself so that it does not limit inner bed cargo space. Such construction allows it to increase the load and storage capacity of the truck. Usually, a bed rack is used to transport different cargo types, such as baggage, kayaks, bikes, tools, surfboards, snowboards, tourist gear, and so on.\nThe accessory's primary use lies in the fact that it does not limit interior storage. At the same time, it allows the vehicle to transport an object that potentially is bigger than its trunk.\nHistory.\nEven though bed racks have gained great popularity over the last decade, the first bed rack was introduced in the 1960s by Pierce Metal Products Inc. Its primary purpose was defined as to build the sides of the carrying box of the truck adjustable to the side of the cargo and to the type of the vehicle.\nModern bed racks resemble the original construction of the 1960s build and are widely used by such known brands as Jeep, Ford, Toyota, and others.\nTypes.\nBed racks are divided into three main categories. Bed racks are:\n1. Crossbar bed rack – two crossbars non-invasively attached to the bed body\n2. Cargo bed racks – a set of interchangeable and customizable rails non-invasively attached to the body of the truck bed\n3. Expedition bed racks – heavy-duty construction with multiple tie-down points, increased load capacity, and impressive storage \nEven though all bed racks are designed for the primary function to increase storage capacity and secure the transported cargo, there are multiple factors to consider when choosing a suitable option. Bed racks vary depending on their functions, weight, load capacity, price range, and general destination. Some bed racks can also be equipped with additional accessories, such as: side rails, kayak mounts, bike mounts, and tent mounts.", "Engineering,_Manufacturing": 0.9983022809, "qwen": "Yes"}
{"id": "72973333", "revid": "14651424", "url": "https://en.wikipedia.org/wiki?curid=72973333", "title": "SC Heerenveen in European football", "text": "SC Heerenveen in European football includes the games which are played by SC Heerenveen in competitions organised by UEFA.\nResults.\n(1990–2000).\n1998-99 season.\n\"Heerenveen won 4–1 on aggregate.\"\n\"Varteks won 5–4 on aggregate.\"\n1999-2000 season.\n\"SC Heerenveen won 4–0 on aggregate.\"\n\"West Ham United won 2–0 on aggregate.\"\n(2001–2010).\n2002-03 season.\n\"National București won 3–2 on aggregate.\"\n2003-04 season.\n\"Heerenveen won 5–1 on aggregate.\"\n\"Heerenveen won 2–1 on aggregate.\"\n\"Villareal won 2–1 on aggregate.\"\n2004-05 season.\n\"Heerenveen won 5-0 on aggregate.\"\n\"Newcastle United won 4–2 on aggregate.\"\n2005-06 season.\n\"Heerenveen won 5–2 on aggregate.\"\n\"Steaua București won 3–2 on aggregate.\"\n2006-07 season.\n\"Heerenveen won 3-0 on aggregate.\"\n2007-08 season.\n\"Helsingborgs won 8–6 on aggregate.\"\n2008-09 season.\n\"Heerenveen won 6–3 on aggregate.\"\n2009-10 season.\n\"Heerenveen 1–1 PAOK on aggregate. Heerenveen won on away goals.\"\n(2010–2020).\n2012-13 season.\n\"Heerenveen won 4–1 on aggregate.\"\n\"Molde won 4–1 on aggregate.\"", "Engineering,_Manufacturing": 0.9999401569, "qwen": "Yes"}
{"id": "72986186", "revid": "12580852", "url": "https://en.wikipedia.org/wiki?curid=72986186", "title": "Integra Technologies", "text": "Integra Technologies is an Outsourced Semiconductor Assembly And Test (OSAT) post processing provider headquartered in Wichita, Kansas, United States. Its current facilities are located in Wichita and Milpitas, California (within Silicon Valley). Their service converts final semiconductor wafers into useable packaged integrated circuits.\nAfter semiconductor companies fabricate wafers at semiconductor fabrication plants (fab / foundry), their final wafers are sent to post processing facilities to cut the wafers into \"dice\" then encapsulate them into integrated circuit (IC) packages, a format that allows other companies to solder the ICs on to printed circuit boards (PCB). Integra Technologies provides post processing services for wafer testing, wafer backgrinding, wafer preparation, wafer dicing, integrated circuit (IC) packaging, IC testing, reliability and qualification testing, counterfeit detection, and related services.\nIntegra is an accredited supplier recommended by the Defense Microelectronics Activity (DMEA) laboratory for post processing of ICs for use by Department of Defense (DoD) programs. It has provided services for more than 100 DoD programs, and various space applications including the Mars rover, Hubble Space Telescope, Orion (spacecraft).\nFacilities.\nThe following is a list of Integra's facilities and future facilities:", "Engineering,_Manufacturing": 1.0000082254, "qwen": "Yes"}
{"id": "73000030", "revid": "14651424", "url": "https://en.wikipedia.org/wiki?curid=73000030", "title": "SBV Vitesse in European football", "text": "SBV Vitesse in European football includes the games which are played by SBV Vitesse in competitions organised by UEFA.\nResults.\n(1990–2000).\n1990-91 season.\n\"Vitesse won 1–0 on aggregate.\"\n\"Vitesse won 5–0 on aggregate.\"\n\"Sporting CP won 4–1 on aggregate.\"\n1992-93 season.\n\"Vitesse won 5–1 on aggregate.\"\n\"Vitesse won 2-0 on aggregate.\"\n\"Real Madrid won 2–0 on aggregate.\"\n1993-94 season.\n\"Norwich City won 3–0 on aggregate.\"\n1994-95 season.\n\"Parma won 2–1 on aggregate.\"\n1997-98 season.\n\"Braga won 3–2 on aggregate.\"\n1998-99 season.\n\"Vitesse won 6–3 on aggregate.\"\n\"Bordeaux won 3–1 on aggregate.\"\n1999-2000 season.\n\"Vitesse won 2–0 on aggregate.\"\n\"Lens won 5–2 on aggregate.\"\n(2001–2010).\n2000-01 season.\n\"Vitesse won 4–2 on aggregate.\"\n\"1–1 on aggregate. Inter win on away goals\"\n2002-03 season.\n\"Vitesse won 2–1 on aggregate.\"\n\"Vitesse won 5–4 on aggregate.\"\n\"Liverpool won 2–0 on aggregate.\"\n(2011–2020).\n2012-13 season.\n\"Vitesse won 7–5 on aggregate.\"\n\"Anzhi Makhachkala won 4–0 on aggregate.\"\n2013-14 season.\n\"FC Petrolul Ploiești won 3–2 on aggregate.\"\n2015-16 season.\n\"Southampton won 5–0 on aggregate.\"\n2018-19 season.\n\"Vitesse won 5–3 on aggregate.\"\n\"Basel won 2–0 on aggregate.\"\n(2021–2030).\n2021-22 season.\n\"Vitesse won 4–3 on aggregate.\"\n\"Vitesse won 5–4 on aggregate.\"\n\"Vitesse won 3–2 on aggregate.\"\n\"Roma won 2–1 on aggregate.\"", "Engineering,_Manufacturing": 0.9999450445, "qwen": "Yes"}
{"id": "73008059", "revid": "44576081", "url": "https://en.wikipedia.org/wiki?curid=73008059", "title": "Taylor-Dunn", "text": "Taylor-Dunn is a manufacturer of industrial electric vehicles. The company was founded in 1949 and is headquartered in Anaheim, California. The vehicles manufactured there are primarily for transporting people and equipment inside warehouses, factories, and work sites. Outdoor users have included airports, college campuses, resorts, and gated subdivisions.\nIn 1949 an Anaheim farmer founded the company, having built an electric cart to use while feeding his chickens. Around 1990 the company was purchased by two electronics executives; by 1992 it had $25 million in annual sales, and about 60% of the market for electric utility vehicles.\nIn 1992 the company expanded to produce full-size trucks, with the Electruck, a larger utility vehicle still targeted for its current customers.\nIn 2016 Polaris Inc. purchased the company, which at the time had 150 employees. Taylor-Dunn reported that it would retain its brand and headquarters. In 2022, Polaris sold Taylor-Dunn and GEM to a group of former Polaris executives. The group would operate both brands at Taylor-Dunn's headquarters under the name Waev, Inc.", "Engineering,_Manufacturing": 0.9999905825, "qwen": "Yes"}
{"id": "191490", "revid": "35227944", "url": "https://en.wikipedia.org/wiki?curid=191490", "title": "Machine tool", "text": "A machine tool is a machine for handling or machining metal or other rigid materials, usually by cutting, boring, grinding, shearing, or other forms of deformations. Machine tools employ some sort of tool that does the cutting or shaping. All machine tools have some means of constraining the workpiece and provide a guided movement of the parts of the machine. Thus, the relative movement between the workpiece and the cutting tool (which is called the toolpath) is controlled or constrained by the machine to at least some extent, rather than being entirely \"offhand\" or \"freehand\". It is a power-driven metal cutting machine which assists in managing the needed relative motion between cutting tool and the job that changes the size and shape of the job material. \nThe precise definition of the term \"machine tool\" varies among users, as discussed below. While all machine tools are \"machines that help people to make things\", not all factory machines are machine tools.\nToday machine tools are typically powered other than by the human muscle (e.g., electrically, hydraulically, or via line shaft), used to make manufactured parts (components) in various ways that include cutting or certain other kinds of deformation.\nWith their inherent precision, machine tools enabled the economical production of interchangeable parts.\nNomenclature and key concepts, interrelated.\nMany historians of technology consider that true machine tools were born when the toolpath first became guided by the machine itself in some way, at least to some extent, so that direct, freehand human guidance of the toolpath (with hands, feet, or mouth) was no longer the only guidance used in the cutting or forming process. In this view of the definition, the term, arising at a time when all tools up till then had been hand tools, simply provided a label for \"tools that were machines instead of hand tools\". Early lathes, those prior to the late medieval period, and modern woodworking lathes and potter's wheels may or may not fall under this definition, depending on how one views the headstock spindle itself; but the earliest historical records of a lathe with direct mechanical control \"of the cutting tool's path\" are of a screw-cutting lathe dating to about 1483. This lathe \"produced screw threads out of wood and employed a true compound slide rest\".\nThe mechanical toolpath guidance grew out of various root concepts:\nAbstractly programmable toolpath guidance began with mechanical solutions, such as in musical box cams and Jacquard looms. The convergence of programmable mechanical control with machine tool toolpath control was delayed many decades, in part because the programmable control methods of musical boxes and looms lacked the rigidity for machine tool toolpaths. Later, electromechanical solutions (such as servos) and soon electronic solutions (including computers) were added, leading to numerical control and computer numerical control.\nWhen considering the difference between freehand toolpaths and machine-constrained toolpaths, the concepts of accuracy and precision, efficiency, and productivity become important in understanding \"why\" the machine-constrained option adds value.\nMatter-Additive, Matter-Preserving, and Matter-Subtractive \"Manufacturing\" can proceed in sixteen ways: Firstly, the work may be held either in a hand, or a clamp; secondly, the tool may be held either in a hand, or a clamp; thirdly, the energy can come from either the hand(s) holding the tool and/or the work, or from some external source, including for examples a foot treadle by the same worker, or a motor, without limitation; and finally, the control can come from either the hand(s) holding the tool and/or the work, or from some other source, including computer numerical control. With two choices for each of four parameters, the types are enumerated to sixteen types of Manufacturing, where Matter-Additive might mean painting on canvas as readily as it might mean 3D printing under computer control, Matter-Preserving might mean forging at the coal fire as readily as stamping license plates, and Matter-Subtracting might mean casually whittling a pencil point as readily as it might mean precision grinding the final form of a laser deposited turbine blade.\nA precise description of what a machine tool is and does in an instant moment is given by a 12 component vector relating the linear and rotational degrees of freedom of the single work piece and the single tool contacting that work piece in any machine arbitrarily and in order to visualize this vector it makes sense to arrange it in four rows of three columns with labels x y and z on the columns and labels spin and move on the rows, with those two labels repeated one more time to make a total of four rows so that the first row might be labeled spin work, the second row might be labeled move work, the third row might be labeled spin tool, and the fourth row might be labeled move tool although the position of the labels is arbitrary which is to say there is no agreement in the literature of mechanical engineering on what order these labels should be but there are 12 degrees of freedom in a machine tool. That said it is important to remember that this is in an instant moment and that instant moment may be a preparatory moment before a tool makes contact with a work piece, or maybe an engaged moment during which contact with work and tool requires an input of rather large amounts of power to get work done which is why machine tools are large and heavy and stiff. Since what these vectors describe our instant moments of degrees of freedom the vector structure is capable of expressing the changing mode of a machine tool as well as expressing its fundamental structure in the following way: imagine a lathe spending a cylinder on a horizontal axis with a tool ready to cut a face on that cylinder in some preparatory moment. What the operator of such a lathe would do is lock the x-axis on the carriage of the lathe establishing a new vector condition with a zero in the x slide position for the tool. Then the operator would unlock the y-axis on the cross slide of the lathe, assuming that our example is were equipped with that, and then the operator would apply some method of traversing the facing tool across the face of the cylinder being cut and a depth combined with the rotational speed selected which engages cutting ability within the power of range of the motor powering the lathe. So the answer to what a machine tool is, is a very simple answer but it's highly technical and is unrelated to the history of machine tools.\nPreceding, there is an answer for what machine tools are. We may consider what they do also. Machine tools produce finished surfaces. They may produce any finish from an arbitrary degree of very rough work to a specular optical grade finish the improvement of which is moot. Machine tools produce the surfaces comprising the features of machine parts by removing chips. These chips may be very rough or even as fine as dust. Every machine tools supports its removal process with a stiff, redundant and so vibration resisting structure because each chip is removed in a semi a synchronous way, creating multiple opportunities for vibration to interfere with precision.\nHumans are generally quite talented in their freehand movements; the drawings, paintings, and sculptures of artists such as Michelangelo or Leonardo da Vinci, and of countless other talented people, show that human freehand toolpath has great potential. The value that machine tools added to these human talents is in the areas of rigidity (constraining the toolpath despite thousands of newtons (pounds) of force fighting against the constraint), accuracy and precision, efficiency, and productivity. With a machine tool, toolpaths that no human muscle could constrain can be constrained; and toolpaths that are technically possible with freehand methods, but would require tremendous time and skill to execute, can instead be executed quickly and easily, even by people with little freehand talent (because the machine takes care of it). The latter aspect of machine tools is often referred to by historians of bytechnology as \"building the skill into the tool\", in contrast to the toolpath-constraining skill being in the \"person\" who wields the tool. As an example, it is \"physically possible\" to make interchangeable screws, bolts, and nuts entirely with freehand toolpaths. But it is \"economically practical\" to make them only with machine tools.\nIn the 1930s, the U.S. National Bureau of Economic Research (NBER) referenced the definition of a machine tool as \"any machine operating by other than hand power which employs a tool to work on metal\".\nThe narrowest colloquial sense of the term reserves it only for machines that perform metal cutting—in other words, the many kinds of [conventional] machining and grinding. These processes are a type of deformation that produces swarf. However, economists use a slightly broader sense that also includes metal deformation of other types that squeeze the metal into shape without cutting off swarf, such as rolling, stamping with dies, shearing, swaging, riveting, and others. Thus presses are usually included in the economic definition of machine tools. For example, this is the breadth of definition used by Max Holland in his history of Burgmaster and Houdaille, which is also a history of the machine tool industry in general from the 1940s through the 1980s; he was reflecting the sense of the term used by Houdaille itself and other firms in the industry. Many reports on machine tool export and import and similar economic topics use this broader definition.\nThe colloquial sense implying [conventional] metal cutting is also growing obsolete because of changing technology over the decades. The many more recently developed processes labeled \"machining\", such as electrical discharge machining, electrochemical machining, electron beam machining, photochemical machining, and ultrasonic machining, or even plasma cutting and water jet cutting, are often performed by machines that could most logically be called machine tools. In addition, some of the newly developed additive manufacturing processes, which are not about cutting away material but rather about adding it, are done by machines that are likely to end up labeled, in some cases, as machine tools. In fact, machine tool builders are already developing machines that include both subtractive and additive manufacturing in one work envelope, and retrofits of existing machines are underway.\nThe natural language use of the terms varies, with subtle connotative boundaries. Many speakers resist using the term \"machine tool\" to refer to woodworking machinery (joiners, table saws, routing stations, and so on), but it is difficult to maintain any true logical dividing line, and therefore many speakers accept a broad definition. It is common to hear machinists refer to their machine tools simply as \"machines\". Usually the mass noun \"machinery\" encompasses them, but sometimes it is used to imply only those machines that are being excluded from the definition of \"machine tool\". This is why the machines in a food-processing plant, such as conveyors, mixers, vessels, dividers, and so on, may be labeled \"machinery\", while the machines in the factory's tool and die department are instead called \"machine tools\" in contradistinction.\nRegarding the 1930s NBER definition quoted above, one could argue that its specificity to metal is obsolete, as it is quite common today for particular lathes, milling machines, and machining centers (definitely machine tools) to work exclusively on plastic cutting jobs throughout their whole working lifespan. Thus the NBER definition above could be expanded to say \"which employs a tool to work on metal \"or other materials of high hardness\"\". And its specificity to \"operating by other than hand power\" is also problematic, as machine tools can be powered by people if appropriately set up, such as with a treadle (for a lathe) or a hand lever (for a shaper). Hand-powered shapers are clearly \"the 'same thing' as shapers with electric motors except smaller\", and it is trivial to power a micro lathe with a hand-cranked belt pulley instead of an electric motor. Thus one can question whether power source is truly a key distinguishing concept; but for economics purposes, the NBER's definition made sense, because most of the commercial value of the existence of machine tools comes about via those that are powered by electricity, hydraulics, and so on. Such are the vagaries of natural language and controlled vocabulary, both of which have their places in the business world.\nHistory.\nForerunners of machine tools included bow drills and potter's wheels, which had existed in ancient Egypt prior to 2500 BC, and lathes, known to have existed in multiple regions of Europe since at least 1000 to 500 BC. But it was not until the later Middle Ages and the Age of Enlightenment that the modern concept of a machine tool—a class of machines used as tools in the making of metal parts, and incorporating machine-guided toolpath—began to evolve. Clockmakers of the Middle Ages and renaissance men such as Leonardo da Vinci helped expand humans' technological milieu toward the preconditions for industrial machine tools. During the 18th and 19th centuries, and even in many cases in the 20th, the builders of machine tools tended to be the same people who would then use them to produce the end products (manufactured goods). However, from these roots also evolved an industry of machine tool builders as we define them today, meaning people who specialize in building machine tools for sale to others.\nHistorians of machine tools often focus on a handful of major industries that most spurred machine tool development. In order of historical emergence, they have been firearms (small arms and artillery); clocks; textile machinery; steam engines (stationary, marine, rail, and otherwise) (the story of how Watt's need for an accurate cylinder spurred Boulton's boring machine is discussed by Roe); sewing machines; bicycles; automobiles; and aircraft. Others could be included in this list as well, but they tend to be connected with the root causes already listed. For example, rolling-element bearings are an industry of themselves, but this industry's main drivers of development were the vehicles already listed—trains, bicycles, automobiles, and aircraft; and other industries, such as tractors, farm implements, and tanks, borrowed heavily from those same parent industries.\nMachine tools filled a need created by textile machinery during the Industrial Revolution in England in the middle to late 1700s. Until that time, machinery was made mostly from wood, often including gearing and shafts. The increase in mechanization required more metal parts, which were usually made of cast iron or wrought iron. Cast iron could be cast in molds for larger parts, such as engine cylinders and gears, but was difficult to work with a file and could not be hammered. Red hot wrought iron could be hammered into shapes. Room temperature wrought iron was worked with a file and chisel and could be made into gears and other complex parts; however, hand working lacked precision and was a slow and expensive process.\nJames Watt was unable to have an accurately bored cylinder for his first steam engine, trying for several years until John Wilkinson invented a suitable boring machine in 1774, boring Boulton & Watt's first commercial engine in 1776.\nThe advance in the accuracy of machine tools can be traced to Henry Maudslay and refined by Joseph Whitworth. That Maudslay had established the manufacture and use of master plane gages in his shop (Maudslay & Field) located on Westminster Road south of the Thames River in London about 1809, was attested to by James Nasmyth who was employed by Maudslay in 1829 and Nasmyth documented their use in his autobiography.\nThe process by which the master plane gages were produced dates back to antiquity but was refined to an unprecedented degree in the Maudslay shop. The process begins with three square plates each given an identification (ex., 1,2 and 3). The first step is to rub plates 1 and 2 together with a marking medium (called bluing today) revealing the high spots which would be removed by hand scraping with a steel scraper, until no irregularities were visible. This would not produce true plane surfaces but a \"ball and socket\" concave-concave and convex-convex fit, as this mechanical fit, like two perfect planes, can slide over each other and reveal no high spots. The rubbing and marking are repeated after rotating 2 relative to 1 by 90 degrees to eliminate concave-convex \"potato-chip\" curvature. Next, plate number 3 is compared and scraped to conform to plate number 1 in the same two trials. In this manner plates number 2 and 3 would be identical. Next plates number 2 and 3 would be checked against each other to determine what condition existed, either both plates were \"balls\" or \"sockets\" or \"chips\" or a combination. These would then be scraped until no high spots existed and then compared to plate number 1. Repeating this process of comparing and scraping the three plates could produce plane surfaces accurate to within millionths of an inch (the thickness of the marking medium).\nThe traditional method of producing the surface gages used an abrasive powder rubbed between the plates to remove the high spots, but it was Whitworth who contributed the refinement of replacing the grinding with hand scraping. Sometime after 1825, Whitworth went to work for Maudslay and it was there that Whitworth perfected the hand scraping of master surface plane gages. In his paper presented to the British Association for the Advancement of Science at Glasgow in 1840, Whitworth pointed out the inherent inaccuracy of grinding due to no control and thus unequal distribution of the abrasive material between the plates which would produce uneven removal of material from the plates.\nWith the creation of master plane gages of such high accuracy, all critical components of machine tools (i.e., guiding surfaces such as machine ways) could then be compared against them and scraped to the desired accuracy.\nThe first machine tools offered for sale (i.e., commercially available) were constructed by Matthew Murray in England around 1800. Others, such as Henry Maudslay, James Nasmyth, and Joseph Whitworth, soon followed the path of expanding their entrepreneurship from manufactured end products and millwright work into the realm of building machine tools for sale.\nImportant early machine tools included the slide rest lathe, screw-cutting lathe, turret lathe, milling machine, pattern tracing lathe, shaper, and metal planer, which were all in use before 1840. With these machine tools the decades-old objective of producing interchangeable parts was finally realized. An important early example of something now taken for granted was the standardization of screw fasteners such as nuts and bolts. Before about the beginning of the 19th century, these were used in pairs, and even screws of the same machine were generally not interchangeable. Methods were developed to cut screw thread to a greater precision than that of the feed screw in the lathe being used. This led to the bar length standards of the 19th and early 20th centuries.\nAmerican production of machine tools was a critical factor in the Allies' victory in World War II. Production of machine tools tripled in the United States in the war. No war was more industrialized than World War II, and it has been written that the war was won as much by machine shops as by machine guns.\nThe production of machine tools is concentrated in about 10 countries worldwide: China, Japan, Germany, Italy, South Korea, Taiwan, Switzerland, US, Austria, Spain and a few others. Machine tool innovation continues in several public and private research centers worldwide.\nDrive power sources.\nMachine tools can be powered from a variety of sources. Human and animal power (via cranks, treadles, treadmills, or treadwheels) were used in the past, as was water power (via water wheel); however, following the development of high-pressure steam engines in the mid 19th century, factories increasingly used steam power. Factories also used hydraulic and pneumatic power. Many small workshops continued to use water, human and animal power until electrification after 1900.\nToday most machine tools are powered by electricity; hydraulic and pneumatic power are sometimes used, but this is uncommon.\nAutomatic control.\nMachine tools can be operated manually, or under automatic control. Early machines used flywheels to stabilize their motion and had complex systems of gears and levers to control the machine and the piece being worked on. Soon after World War II, the numerical control (NC) machine was developed. NC machines used a series of numbers punched on paper tape or punched cards to control their motion. In the 1960s, computers were added to give even more flexibility to the process. Such machines became known as computerized numerical control (CNC) machines. NC and CNC machines could precisely repeat sequences over and over, and could produce much more complex pieces than even the most skilled tool operators.\nBefore long, the machines could automatically change the specific cutting and shaping tools that were being used. For example, a drill machine might contain a magazine with a variety of drill bits for producing holes of various sizes. Previously, either machine operators would usually have to manually change the bit or move the work piece to another station to perform these different operations. The next logical step was to combine several different machine tools together, all under computer control. These are known as machining centers, and have dramatically changed the way parts are made.\nExamples.\nExamples of machine tools are:\nWhen fabricating or shaping parts, several techniques are used to remove unwanted metal. Among these are:\nOther techniques are used to \"add\" desired material. Devices that fabricate components by selective \"addition\" of material are called rapid prototyping machines.\nMachine tool manufacturing industry.\nThe worldwide market for machine tools was approximately $81 billion in production in 2014 according to a survey by market research firm Gardner Research. The largest producer of machine tools was China with $23.8 billion of production followed by Germany and Japan at neck and neck with $12.9 billion and $12.88 billion respectively. South Korea and Italy rounded out the top 5 producers with revenue of $5.6 billion and $5 billion respectively.", "Engineering,_Manufacturing": 0.9999337196, "qwen": "Yes"}
{"id": "24086624", "revid": "3138265", "url": "https://en.wikipedia.org/wiki?curid=24086624", "title": "Supply chain surplus", "text": "Supply chain surplus is the value addition by supply chain function of an organisation. It is calculated by the following formula:\nDefinition and Example.\nSupply chain surplus, also known as supply chain profitability, is a common term that represents value addition by supply chain function of an organization. Jonathan Birkin also defines supply chain surplus as \"the difference between the revenue generated from the customers and the overall cost across that supply chain.\" The operational concept of it is 'sharing the profit that remains after subtracting costs incurred in the production and delivery of products or services. Ideally, profit is distributed to supply chain partners via transfer prices.'\nFor example, a consumer buys a PC from Samsung at $2,500, which indicates the revenue supply chain achieved. All the stages incur costs to ensure the efficient transfer of funds, information, storage of the product and transportation to the final consumer. The difference between revenue from selling the PC and the supply chain cost represents the supply chain surplus or supply chain profitability. Supply chain surplus is the total profit shared by all the stages and intermediaries. The greater the supply chain surplus, the more successful the supply chain. The success of supply chain calculated by its overall surplus not by the profit at each part of stages.\nFormula.\nSupply chain surplus can be calculated by the following formulae:\nThese terms were coined by Sunil Chopra, of the Kellogg School of Management and Peter Meindl, of Kepos Capital.\nMaximising surplus.\nMaximising supply chain surplus is an ultimate objective of the supply chain planning. When we look the amount of supply chain surplus, the success of that supply chain system and its future prospects can be known. To maximise supply chain surplus, every facility that impacts costs must be considered. However, Hugos said that, among those, 'the customer must be the starting point when trying to increase the supply chain surplus because all demand, and therefore revenue, ultimately arises from them.'\nTraceability and Transparency.\nAccording to Pagell et al., supply chain surplus is related to sustainability and can be further understood through the practices of traceability and transparency. \"Traceability\" is 'the practice of sharing information among supply chain partners about materials that meet industry standards for minimising environmental risk', and \"Transparency\" is 'the flow of money through the entire supply chain with an explicit goal of ensuring that each organisation makes enough of a profit to do more than just subsist'. In essence, \"traceability\" is concerned with how things are made throughout the chain while \"transparency\" is concerned with keeping profits flowing through the entire chain. To maximise surplus, it is important to ensure continuity of the supply chain system by letting each partner in the chain reinvest, innovate, and grow.\nOutsourcing.\nBy aggregating capacity, inventory, inbound or outbound transportation, warehousing, procurement, information, receivables to higher level, outsourcing to a third party can provide a sustainable growth of the surplus to the firm. Sometimes, a growth in surplus may also occur due to lower cost, higher quality, specialization or learning of the third party. A firm gains most from outsourcing to a third party if needs are small, uncertainty is high and other firms are also sourcing from the same third party.\nTax efficient management.\nTo maximise supply chain surplus, the effect of tax in the design and implementation of supply chain management is also considered. As the result of globalization, now there are so many cross-national businesses. As different countries have different tax rates, companies may legally optimise their supply chain and increase profits based on tax efficiency.", "Engineering,_Manufacturing": 0.9911870956, "qwen": "Yes"}
{"id": "24095515", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=24095515", "title": "Pilot Industries", "text": "Pilot Industries was an American company that developed and manufactured fuel and fluid handling systems primarily for the automotive industry. Other products included non-destructive test systems and injection molding equipment. Established in 1977, Pilot's corporate headquarters were in Ann Arbor, Michigan, with technical centers in Dexter, Michigan and in the UK. Manufacturing facilities were located in Dexter, Michigan (2 plants); Manchester, Michigan; Clare, Michigan; Reed City, Michigan; Sterling Heights, Michigan; North Vernon, Indiana; Born, Netherlands; and Saltillo, Mexico.\nAmong the companies they made parts for were Ford, General Motors, Harrison Radiator Corporation, and Chrysler. A large percentage of the parts were fuel lines for Ford's F-150 and Ranger.\nHistory.\nPilot was a plastic extrusion co. Until they acquired R&C Fabricators, Big Rapids, Mi, which was a metal tubing manufacturing co. in 1990.\nDue to heat issues with the extruded nylon fuels line supplied to Ford by Pilot, Ford insisted Pilot develop metals manufacturing capability in order to retain their current supplier contracts.\nWith the addition of metals capabilities Pilot retained the Ford contracts, and Pilot Metal products grew from $100,000 in sales in 1991 to over $35m in sales by 1998. It was not until the mid 1990s that PCap was able to be developed, based on the profitability and success of the Metals Div.\nPilot Industries rose to success based on its patented PCAP tubing, developed by Ed Krause. PCAP is a multi-layered tubing with Teflon being the inner layer, and prevented fuel vapor from escaping through the walls of the tubing, important for emissions regulations.\nOn January 31, 2002, the company was purchased out of bankruptcy by Cerberus Capital Management, a private equity firm, and later that year sold to Martinrea International.", "Engineering,_Manufacturing": 1.000007391, "qwen": "Yes"}
{"id": "24101751", "revid": "14965160", "url": "https://en.wikipedia.org/wiki?curid=24101751", "title": "Surface integrity", "text": "Surface integrity is the surface condition of a workpiece after being modified by a manufacturing process. The term was coined by Michael Field and John F. Kahles in 1964.\nThe surface integrity of a workpiece or item changes the material's properties. The consequences of changes to surface integrity are a mechanical engineering design problem, but the preservation of those properties are a manufacturing consideration.\nSurface integrity can have a great impact on a parts function; for example, Inconel 718 can have a fatigue limit as high as after a gentle grinding or as low as after electrical discharge machining (EDM).\nDefinition.\nThere are two aspects to surface integrity: \"topography characteristics\" and \"surface layer characteristics\". The topography is made up of surface roughness, waviness, errors of form, and flaws. The surface layer characteristics that can change through processing are: plastic deformation, residual stresses, cracks, hardness, overaging, phase changes, recrystallization, intergranular attack, and hydrogen embrittlement. When a traditional manufacturing process is used, such as machining, the surface layer sustains local plastic deformation.\nThe processes that affect surface integrity can be conveniently broken up into three classes: \"traditional processes\", \"non-traditional processes\", and \"finishing treatments\". Traditional processes are defined as processes where the tool contacts the workpiece surface; for example: grinding, turning, and machining. These processes will only damage the surface integrity if the improper parameters are used, such as dull tools, too high feed speeds, improper coolant or lubrication, or incorrect grinding wheel hardness. Nontraditional processes are defined as processes where the tool does not contact the workpiece; examples of this type of process include EDM, electrochemical machining, and chemical milling. These processes will produce different surface integrity depending on how the processes are controlled; for instance, they can leave a stress-free surface, a remelted surface, or excessive surface roughness. Finishing treatments are defined as processes that negate surface finishes imparted by traditional and non-traditional processes or improve the surface integrity. For example, compressive residual stress can be enhanced via peening or roller burnishing or the recast layer left by EDMing can be removed via chemical milling.\nFinishing treatments can affect the workpiece surface in a wide variety of manners. Some clean and/or remove defects, such as scratches, pores, burrs, flash, or blemishes. Other processes improve or modify the surface appearance by improving smoothness, texture, or color. They can also improve corrosion resistance, wear resistance, and/or reduce friction. Coatings are another type of finishing treatment that may be used to plate an expensive or scarce material onto a less expensive base material.\nVariables.\nManufacturing processes have five main variables: the workpiece, the tool, the machine tool, the environment, and process variables. All of these variables can affect the surface integrity of the workpiece by producing:", "Engineering,_Manufacturing": 0.999892354, "qwen": "Yes"}
{"id": "22039695", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=22039695", "title": "Shop floor", "text": "The shop floor is the production area, such as in a factory or another working space and is the floor where workers produce goods. The term \"shop floor\" refers to the area of a factory where production takes place. The shop floor excludes the area used or designated for administrative activities.\nShop stewards and Shop Stewards Movement.\nA shop steward is an employee of a company or organization who, as a labor union member and official, represents and defends the interests of their coworkers. During the First World War, the Shop Stewards Movement brought together shop stewards from across the United Kingdom. It began with the Clyde Workers Committee, Britain's first shop stewards committee, which organized in response to the imprisonment of three of their members in 1915.\nShop floor control.\nSystems for managing the various components of the manufacturing process are known as shop floor control (SFC) systems.\nShop floor control is one of the functions of manufacturing control; it is the process of monitoring the production activities as they happen, such as when the product is being processed, assembled, inspected, etc. It is also concerned with the shop floor inventories—short and excessive inventories that may cause losses.\nIntegrated shop floor management.\nThe manufacturing industry is significantly impacted by technological advances such as the Internet, the Web, and intelligent agents. Changing shop floor environments and customer needs are sufficed with new kinds of shop floor control systems that are web-based shop floor control systems, also called e-shop floor or i-shop floor.", "Engineering,_Manufacturing": 0.9999785423, "qwen": "Yes"}
{"id": "22051259", "revid": "1116755184", "url": "https://en.wikipedia.org/wiki?curid=22051259", "title": "Mechanical alloying", "text": "Mechanical alloying (MA) is a solid-state and powder processing technique involving repeated cold welding, fracturing, and re-welding of blended powder particles in a high-energy ball mill to produce a homogeneous material. Originally developed to produce oxide-dispersion strengthened (ODS) nickel- and iron-base superalloys for applications in the aerospace industry, MA has now been shown to be capable of synthesizing a variety of equilibrium and non-equilibrium alloy phases starting from blended elemental or pre-alloyed powders. The non-equilibrium phases synthesized include supersaturated solid solutions, metastable crystalline and quasicrystalline phases, nanostructures, and amorphous alloys.\nMetal mixes.\nMechanical alloying is akin to metal powder processing, where metals may be mixed to produce superalloys. Mechanical alloying occurs in three steps. First, the alloy materials are combined in a ball mill and ground to a fine powder. A hot isostatic pressing (HIP) process is then applied to simultaneously compress and sinter the powder. A final heat treatment stage helps remove existing internal stresses produced during any cold compaction which may have been used. This produces an alloy suitable for high heat turbine blades and aerospace components.\nDesign.\nDesign parameters include type of mill, milling container, milling speed, milling time, type, size, and size distribution of the grinding medium, ball-to-powder weight ratio, extent of filling the vial, milling atmosphere, process control agent, temperature of milling, and the reactivity of the species.\nProcess.\nThe process of mechanical alloying involves the production of a composite powder particles by:\nMilling.\nDuring high-energy milling the powder particles are repeatedly flattened, cold welded, fractured and rewelded. Whenever two steel balls collide, some powder is trapped between them. Typically, around 1000 particles with an aggregate weight of about 0.2 mg are trapped during each collision. The force of the impact plastically deforms the powder particles, leading to work hardening and fracture. The new surfaces thus created enable the particles to weld together; this leads to an increase in particle size. Since in the early stages of milling, the particles are soft (if using either ductile-ductile or ductile-brittle material combination), their tendency to weld together and form large particles is high. A broad range of particle sizes develops, with some as large as three times larger than the starting particles. The composite particles at this stage have a characteristic layered structure consisting of various combinations of the starting constituents. With continued deformation particles become work hardened, and fracture by a fatigue failure mechanism and/or by the fragmentation of fragile flakes.", "Engineering,_Manufacturing": 1.0000058413, "qwen": "Yes"}
{"id": "2381066", "revid": "39872398", "url": "https://en.wikipedia.org/wiki?curid=2381066", "title": "Platen", "text": "A platen (or platten) is a flat platform with a variety of roles in printing or manufacturing. It can be a flat metal (or earlier, wooden) plate pressed against a medium (such as paper) to cause an impression in letterpress printing. Platen may also refer to a typewriter roller which friction-feeds paper into position below the typebars or print head. It can refer to the glass surface of a copier, and the rotating disk used to polish semiconductor wafers.\nOther applications.\nOffice equipment.\nIn office copiers and scanners, the platen is a flat glass surface on which operators place papers or books for scanning. The platen is also called the flatbed. Platens are also used in some printers, such as the dot-matrix printer.\nManufacturing and processing.\nSemiconductor manufacturing.\nIn semiconductor manufacturing, specifically chemical-mechanical planarization, a flat, rotating platen covered with a pad is used to polish semiconductor wafers (see image).\nScreen printing.\nIn textile screen printing, a platen is a flat board onto which the operator slides the garment. It is generally made of either a plywood laminate or aluminum with a rubber laminate. Often the platen will be pretreated with a spray adhesive. This allows the garment to effectively become a rigid immobile substrate, especially important when printing multiple colors or utilizing an on-press infrared dryer. The screen is brought parallel and close to the garment (often within 1/32\") and the squeegee pressure then brings the screen into contact with the garment so that the ink transfer may occur. There are many special platen types, such as those for printing sleeves or pockets, vacuum platens, platens with clamps to hold bulky materials such as jackets, and even curved platens for printing on hats.\nWoodworking.\nIn woodworking, wide belt sanders use platens to press the sanding paper into contact with the wood being sanded. The platen sits between two steel rolls which deliver the moving force to the sanding belt. Sanding heads with a platen are used on finish sanding with papers of finer grits, when the coarser ones are typically used with contact drum type sanding heads. Stock is fed into and out of the machine on a conveyor belt. Since the abrasive belt creates a substantial pressure on the stock that tends to push the stock toward the infeed, the hold down shoes and rollers hold the workpiece down against the belt while it is moving through the machine in order to ensure uniform contact with the abrasive and continuous movement.\nMetal forming.\nIn metal forming processes, a platen is the component that houses the mold for forging the required shape. The platen tends to be the heaviest and strongest part of the press due to the massive forces that it has to withstand. A platen for a 5000-ton press can weigh up to 350 tons.\nOther.\nIn manufacturing, a platen is a flat plate of a press utilized in laminate, plastic and forest product industries. A platen is typically heated with oil, water, steam or electricity and is used in the production of furniture, tires, gaskets, particle board, composite heaters and plywood. In high frequency welding products, platens are used to put lines on PVC binders and folders down the spine lines.\nPlatens are utilized in impact testing in research; a specimen is crushed between platens.\nThe platen also refers to the fixed part of a linear motor.", "Engineering,_Manufacturing": 1.000005722, "qwen": "Yes"}
{"id": "2383713", "revid": "44120587", "url": "https://en.wikipedia.org/wiki?curid=2383713", "title": "Pick-and-place machine", "text": "Surface-mount technology (SMT) component placement systems, commonly called pick-and-place machines or P&Ps, are robotic machines which are used to place surface-mount devices (SMDs) onto a printed circuit board (PCB). They are used for high speed, high precision placing of a broad range of electronic components, for example capacitors, resistors, integrated circuits onto the PCBs which are in turn used in computers, consumer electronics as well as industrial, medical, automotive, military and telecommunications equipment. Similar equipment exists for through-hole components.\nThis type of equipment is sometimes used to package microchips using the flip chip method.\nHistory.\n1980s and 1990s.\nDuring this time, a typical SMT assembly line employed two different types of pick-and-place (P&P) machines arranged in sequence.\nThe unpopulated board was fed into a rapid placement machine. These machines, sometimes called chip shooters, place mainly low-precision, simple package components such as resistors and capacitors. These high-speed P&P machines were built around a single turret design capable of mounting up to two dozen stations. As the turret spins, the stations passing the back of the machine pick up parts from tape feeders mounted on a moving carriage. As the station proceeds around the turret, it passes an optical station that calculates the angle at which the part was picked up, allowing the machine to compensate for drift. Then, as the station reaches the front of the turret, the board is moved into the proper position, the nozzle is spun to put the part in proper angular orientation, and the part is placed on the board. Typical chip shooters can, under optimal conditions, place up to 53,000 parts per hour, or almost 15 parts per second.\nBecause the PCB is moved rather than the turret, only lightweight parts that will not be shaken loose by the violent motion of the PCB can be placed this way.\nFrom the high speed machine, the board transits to a precision placement machine. These pick-and-place machines often use high resolution verification cameras and fine adjustment systems via high precision linear encoders on each axis to place parts more accurately than the high-speed machines. Furthermore, the precision placement machines are capable of handling larger or more irregularly shaped parts such as large package integrated circuits or packaged inductor coils and trimpots. Unlike the rapid placers, precision placers generally do not use turret mounted nozzles and instead rely on a gantry-supported moving head. These precision placers rely upon placement heads with relatively few pickup nozzles. The head sometimes has a laser identifier that scans a reflective marker on the PC board to orient the head to the board. Parts are picked up from tape feeders or trays, scanned by a camera (on some machines), and then placed in the proper position on the board. Some machines also center the parts on the head with two arms that close to center the part; the head then rotates 90 degrees and the arms close again to center the part once more. The margin of error for some components is, in many cases, less than half a millimeter (less than 0.02 inches). \n2000 to present.\nDue to the huge cost of having two separate machines to place parts, the speed limitations of the chip shooters, and the inflexibility of the machines, the electronic component machine manufacturers abandoned the technique. To overcome these limitations they moved to an all-in-one modular, multi-headed, and multi-gantry machines that could have heads quickly swapped on different modules depending on the product being built to machines with multiple mini turrets capable of placing the whole spectrum of components with theoretical speeds of 136,000 components an hour. The fastest machines can have speeds of up to 200,000 CPH (components per hour).\n2010 onwards.\nSwapping heads onboard placement machines required more inventory of heads and related spare parts for different heads to minimize the downtime. Placement machines have an all-in-one head that can place components ranging from 0.4 mm × 0.2 mm to 50 mm × 40 mm.\nIn addition to this there was a new concept wherein the user could borrow performance during peak periods.\nThere is a big change in the industry approach these days with more focus on software applications for the process. With new applications like POP and wafer placement on substrate the industry is moving beyond conventional component placement.\nThere is a big difference in the needs of SMT users. For many, the high speed machines are not suitable due to cost and speed. With recent changes in the economic climate the requirement for SMT placement becomes focused on the machine's versatility to deal with short runs and fast changeover. This means that lower cost machines with vision systems provide an affordable option for SMT users. There are more users of low end and mid-range machines than the ultra fast placement systems.\nSMT pick and place machine manufacturers include:\nOperation.\nThe placement equipment is part of a larger overall machine that carries out specific programmed steps to create a PCB assembly. Several sub-systems work together to \"pick up\" and correctly \"place\" the components onto the PCB. These systems normally use pneumatic suction cups, attached to a plotter-like device to allow the cup to be accurately manipulated in three dimensions. Additionally, each nozzle can be rotated independently.\nComponent feeds.\nSurface mount components are placed along the front (and often back) faces of the machine. Most components are supplied on paper or plastic tape, in tape reels that are loaded onto feeders mounted to the machine. Larger integrated circuits (ICs) are sometimes supplied arranged in trays which are stacked in a compartment. More commonly used ICs will be provided in tapes rather than trays or sticks. Improvements in feeder technology mean that tape format is becoming the preferred method of presenting parts on an SMT machine.\nEarly feeder heads were much bulkier, and as a result it was not designed to be the mobile part of the system. Rather, the PCB itself was mounted on a moving platform that aligned the areas of the board to be populated with the feeder head above.\nConveyor belt.\nThrough the middle of the machine there is a conveyor belt, along which blank PCBs travel, and a PCB clamp in the center of the machine. The PCB is clamped, and the nozzles pick up individual components from the feeders/trays, rotate them to the correct orientation and then place them on the appropriate pads on the PCB with high precision. High-end machines can have multiple conveyors to produce multiple same or different kinds of products simultaneously.\nInspection and visual system.\nThe part being carried from the part feeders on either side of the conveyor belt to the PCB, it is photographed from below by using high resolution camera and lighting system. Its silhouette is inspected to see if it is damaged or missing (was not picked up), and the inevitable registration errors in pickup are measured and compensated for when the part is placed. For example, if the part was shifted 0.25 mm and rotated 10° when picked up, the pickup head will adjust the placement position to place the part in the correct location.\nSome machines have these optical systems on the robot arm and can carry out the optical calculations without losing time, thereby achieving a lower derating factor.\nThe high-end optical systems mounted on the heads can also be used to capture details of the non-standard type components and save them to a database for future use. In addition to this, advanced software is available for monitoring the production and interconnect database — of the production floor to that of supply chain — in real-time. ASM provides an optional feature for increasing accuracy while placing LED components on a high end product where in the optical center of the LED is critical rather than the calculated mechanical center based on the component's lead structure. The special camera system measures both physical and optical center and makes the necessary adjustments before placement. It also can acquire the images in either single field of view multiple field of view modes.\nA separate camera on the pick-and-place head photographs fiducial marks on the PCB to measure its position on the conveyor belt accurately. Two fiducial marks, measured in two dimensions each, usually placed diagonally, let the PCB's orientation and thermal expansion be measured and compensated for as well. Some machines are also able to measure the PCB shear by measuring a third fiducial mark on the PCB.\nVariations.\nTo minimize the distance the pickup gantry must travel, it is common to have multiple nozzles with separate vertical motion on a single gantry. This can pick up multiple parts with one trip to the feeders. Also, advanced software in the newer generation machines allows different robotic heads to work independently of each other to further increase the throughput.\nThe components may be temporarily adhered to the PCB using the wet solder paste itself, or by using small blobs of a separate adhesive, applied by a glue-dispensing machine that can be incorporated on to the pick and place machine. The glue is added before component placement. It is dispensed by nozzles or by using jet dispensing. Jet dispensing dispenses material by shooting it towards the target, which in this case, is the circuit board.", "Engineering,_Manufacturing": 1.0000083447, "qwen": "Yes"}
{"id": "2384013", "revid": "1167358870", "url": "https://en.wikipedia.org/wiki?curid=2384013", "title": "Extrusion moulding", "text": "Extrusion is a manufacturing process used to make pipes, hoses, drinking straws, curtain tracks, rods, and fibre. The granules melt into a liquid which is forced through a die, forming a long 'tube like' shape. The shape of the die determines the shape of the tube. The extrusion is then cooled and forms a solid shape. The tube may be printed upon, and cut at equal intervals. The pieces may be rolled for storage or packed together.\nShapes that can result from extrusion include T-sections, U-sections, square sections, I-sections, L-sections and circular sections.\nOne of the most famous products of extrusion moulding is the optical fiber cable.\nExtrusion is similar to injection moulding except that a long continuous shape is produced.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "2389550", "revid": "43638649", "url": "https://en.wikipedia.org/wiki?curid=2389550", "title": "Milling cutter", "text": "Milling cutters are cutting tools typically used in milling machines or machining centres to perform milling operations (and occasionally in other machine tools). They remove material by their movement within the machine (e.g., a ball nose mill) or directly from the cutter's shape (e.g., a form tool such as a hobbing cutter).\nFeatures of a milling cutter.\nMilling cutters come in several shapes and many sizes. There is also a choice of coatings, as well as rake angle and number of cutting surfaces.\nTypes.\nEnd mill.\nEnd mills (middle row in image) are those tools that have cutting teeth at one end, as well as on the sides. The words \"end mill\" are generally used to refer to flat bottomed cutters, but also include rounded cutters (referred to as \"ball nosed\") and radiused cutters (referred to as \"bull nose\", or \"torus\"). They are usually made from high speed steel or cemented carbide, and have one or more flutes. They are the most common tool used in a vertical mill.\nRoughing end mill.\nRoughing end mills quickly remove large amounts of material. This kind of end mill utilizes a wavy tooth form cut on the periphery. These wavy teeth act as many successive cutting edges producing many small chips. This results in a relatively rough surface finish, but the swarf takes the form of short thin sections and is more manageable than a thicker more ribbon-like section, resulting in smaller chips that are easier to clear. During cutting, multiple teeth are in simultaneous contact with the workpiece, reducing chatter and vibration. Rapid stock removal with heavy milling cuts is sometimes called \"hogging\". Roughing end mills are also sometimes known as \"rippa\" or \"ripper\" cutters.\nBall cutter.\n\"Ball nose\" cutters or \"ball end\" mills (lower row in image) are similar to slot drills, but the end of the cutters are hemispherical. They are ideal for machining 3-dimensional contoured shapes in machining centres, for example in moulds and dies. They are sometimes called \"ball mills\" in shop-floor slang, despite the fact that that term also has another meaning. They are also used to add a radius between perpendicular faces to reduce stress concentrations.\nA \"bull nose\" cutter mills a slot with a corner radius, intermediate between an end mill and ball cutter; for example, it may be a 20 mm diameter cutter with a 2 mm radius corner. The silhouette is essentially a rectangle with its corners truncated (by either a chamfer or radius).\nSlab mill.\nSlab mills are used either by themselves or in gang milling operations on manual horizontal or universal milling machines to machine large broad surfaces quickly. They have been superseded by the use of cemented carbide-tipped face mills which are then used in vertical mills or machining centres.\nSide-and-face cutter.\nThe side-and-face cutter is designed with cutting teeth on its side as well as its circumference. They are made in varying diameters and widths depending on the application. The teeth on the side allow the cutter to make \"unbalanced cuts\" (cutting on one side only) without deflecting the cutter as would happen with a slitting saw or slot cutter (no side teeth).\nCutters of this form factor were the earliest milling cutters developed. From the 1810s to at least the 1880s they were the most common form of milling cutter, whereas today that distinction probably goes to end mills. Traditionally, HSS side and face cutters are used to mill slots and grooves.\nInvolute gear cutter.\nThere are 8 cutters (excluding the rare half sizes) that will cut gears from 12 teeth through to a rack (infinite diameter).\nHob.\nThese cutters are a type of form tool and are used in hobbing machines to generate gears. A cross-section of the cutter's tooth will generate the required shape on the workpiece, once set to the appropriate conditions (blank size). A hobbing machine is a specialised milling machine.\nThread mill.\nWhereas a hob engages the work much as a mating gear would (and cuts the blank progressively until it reaches final shape), a thread milling cutter operates much like an endmill, traveling around the work in a helical interpolation.\nFace mill.\nA face mill is a cutter designed for facing as opposed to e.g., creating a pocket (end mills). The cutting edges of face mills are always located along its sides. As such it must always cut in a horizontal direction at a given depth coming from outside the stock. Multiple teeth distribute the chip load, and since the teeth are normally disposable carbide inserts, this combination allows for very large and efficient face milling. \nFly cutter.\nA fly cutter is composed of a body into which one or two tool bits are inserted. As the entire unit rotates, the tool bits take broad, shallow facing cuts. Fly cutters are analogous to face mills in that their purpose is face milling and their individual cutters are replaceable. Face mills are more ideal in various respects (e.g., rigidity, indexability of inserts without disturbing effective cutter diameter or tool length offset, depth-of-cut capability), but tend to be expensive, whereas fly cutters are very inexpensive.\nMost fly cutters simply have a cylindrical center body that holds one tool bit. It is usually a standard left-hand turning tool that is held at an angle of 30 to 60 degrees. Fly cutters with two tool bits have no \"official\" name but are often called double fly cutters, double-end fly cutters, or fly bars. The latter name reflects that they often take the form of a bar of steel with a tool bit fastened on each end. Often these bits will be mounted at right angles to the bar's main axis, and the cutting geometry is supplied by using a standard right-hand turning tool.\nRegular fly cutters (one tool bit, swept diameter usually less than 100 mm) are widely sold in machinists' tooling catalogs. Fly bars are rarely sold commercially; they are usually made by the user. Fly bars are perhaps a bit more dangerous to use than endmills and regular fly cutters because of their larger swing. As one machinist put it, running a fly bar is like \"running a lawn mower without the deck\", that is, the exposed swinging cutter is a rather large opportunity to take in nearby hand tools, rags, fingers, and so on. However, given that a machinist can never be careless with impunity around rotating cutters or workpieces, this just means using the same care as always except with slightly higher stakes. Well-made fly bars in conscientious hands give years of trouble-free, cost-effective service for the facing off of large polygonal workpieces such as die/mold blocks.\nWoodruff cutter.\nWoodruff cutters are used to cut the keyway for a woodruff key.\nHollow mill.\nHollow milling cutters, more often called simply \"hollow mills\", are essentially \"inside-out endmills\". They are shaped like a piece of pipe (but with thicker walls), with their cutting edges on the inside surface. They were originally used on turret lathes and screw machines as an alternative to turning with a box tool, or on milling machines or drill presses to finish a cylindrical boss (such as a trunnion). Hollow mills can be used on modern CNC lathes and Swiss style machines. An advantage to using an indexable adjustable hollow mill on a Swiss-style machine is replacing multiple tools.  By performing multiple operations in a single pass, the machine does not need as can accommodate other tools in the tool zone and improves productivity.\nMore advanced hollow mills use indexable carbide inserts for cutting, although traditional high speed steel and carbide-tipped blades are still used.\nHollow milling has an advantage over other ways of cutting because it can perform multiple operations. A hollow mill can reduce the diameter of a part and also perform facing, centering, and chamfering in a single pass.\nHollow mills offer an advantage over single point tooling. Multiple blades allow the feed rate to double and can hold a closer concentricity. The number of blades can be as many as 8 or as few as 3.  For significant diameter removal (roughing), more blades are necessary.\nTrepanning is also possible with a hollow mill. Special form blades can be used on a hollow mill for trepanning diameters, forms, and ring grooves.\nInterpolation is also not necessary when using a hollow mill; this can result in a significant reduction of production time.\nBoth convex and concave spherical radii are possible with a hollow mill. The multiple blades of a hollow mill allow this radius to be produced while holding a tight tolerance. \nA common use of a hollow mill is preparing for threading.  The hollow mill can create a consistent pre-thread diameter quickly, improving productivity.\nAn adjustable hollow mill is a valuable tool for even a small machine shop to have because the blades can be changed out for an almost infinite number of possible geometries.\nDovetail cutter.\nA dovetail cutter is an end mill whose form leaves behind a dovetail slot, such as often forms the ways of a machine tool.\nShell mill.\nModular principle.\nA shell mill is any of various milling cutters (typically a face mill or endmill) whose construction takes a modular form, with the shank (arbor) made separately from the body of the cutter, which is called a \"shell\" and attaches to the shank/arbor via any of several standardized joining methods.\nThis modular style of construction is appropriate for large milling cutters for about the same reason that large diesel engines use separate pieces for each cylinder and head whereas a smaller engine would use one integrated casting. Two reasons are that (1) for the maker it is more practical (and thus less expensive) to make the individual pieces as separate endeavors than to machine all their features in relation to each other while the whole unit is integrated (which would require a larger machine tool work envelope); and (2) the user can change some pieces while keeping other pieces the same (rather than changing the whole unit). One arbor (at a hypothetical price of USD100) can serve for various shells at different times. Thus 5 different milling cutters may require only USD100 worth of arbor cost, rather than USD500, as long as the workflow of the shop does not require them all to be set up simultaneously. It is also possible that a crashed tool scraps only the shell rather than both the shell and arbor. To also avoid damage to the shell, many cutters, especially in larger diameters, also have another replaceable part called shim, which is mounted to the shell and the inserts are mounted on the shim. That way, in case of light damage, only the insert and maximum the shim needs replacement. The shell is safe. This would be like crashing a \"regular\" endmill and being able to reuse the shank rather than losing it along with the flutes.\nMost shell mills made today use indexable inserts for the cutting edges—thus shank, body, and cutting edges are all modular components.\nMounting methods.\nThere are several common standardized methods of mounting shell mills to their arbors. They overlap somewhat (not entirely) with the analogous joining of lathe chucks to the spindle nose.\nThe most common type of joint between shell and arbor involves a fairly large cylindrical feature at center (to locate the shell concentric to the arbor) and two driving lugs or tangs that drive the shell with a positive engagement (like a dog clutch). Within the central cylindrical area, one or several socket head cap screws fasten the shell to the arbor.\nAnother type of shell fastening is simply a large-diameter fine thread. The shell then screws onto the arbor just as old-style lathe chuck backplates screw onto the lathe's spindle nose. This method is commonly used on the 2\" or 3\" boring heads used on knee mills. As with the threaded-spindle-nose lathe chucks, this style of mounting requires that the cutter only make cuts in one rotary direction. Usually (i.e., with right-hand helix orientation) this means only M03, never M04, or in pre-CNC terminology, \"only forward, never reverse\". One could use a left-hand thread if one needed a mode of use involving the opposite directions (i.e., only M04, never M03).\nUsing a milling cutter.\nChip formation.\nAlthough there are many different types of milling cutter, understanding chip formation is fundamental to the use of any of them.\nAs the milling cutter rotates, the material to be cut is fed into it, and each tooth of the cutter cuts away a small chip of material. Achieving the correct size of chip is of critical importance. The size of this chip depends on several variables.\nThe machinist needs three values: S, F and Depth when deciding how to cut a new material with a new tool. However, he will probably be given values of Vc and Fz from the tool manufacturer. S and F can be calculated from them:\nConventional milling versus climb milling.\nA milling cutter can cut in two directions, sometimes known as \"conventional\" or \"up\" and \"climb\" or \"down\".\nCutter location (cutter radius compensation).\nCutter location is the topic of where to locate the cutter in order to achieve the desired contour (geometry) of the workpiece, given that the cutter's size is non-zero. The most common example is cutter radius compensation (CRC) for endmills, where the centerline of the tool will be offset from the target position by a vector whose \"distance\" is equal to the cutter's radius and whose \"direction\" is governed by the left/right, climb/conventional, up/down distinction. In most implementations of G-code, it is G40 through G42 that control CRC (G40 cancel, G41 left/climb, G42 right/conventional). The radius values for each tool are entered into the offset register(s) by the CNC operator or machinist, who then tweaks them during production in order to keep the finished sizes within tolerance. Cutter location for 3D contouring in 3-, 4-, or 5-axis milling with a ball-endmill is handled readily by CAM software rather than manual programming. Typically the CAM vector output is postprocessed into G-code by a postprocessor program that is tailored to the particular CNC control model. Some late-model CNC controls accept the vector output directly, and do the translation to servo inputs themselves, internally.\nSwarf removal.\nAnother important quality of the milling cutter to consider is its ability to deal with the swarf generated by the cutting process. If the swarf is not removed as fast as it is produced, the flutes will clog and prevent the tool cutting efficiently, causing vibration, tool wear and overheating. Several factors affect swarf removal, including the depth and angle of the flutes, the size and shape of the chips, the flow of coolant, and the surrounding material. It may be difficult to predict, but a good machinist will watch out for swarf build up, and adjust the milling conditions if it is observed.\nSelecting a milling cutter.\nSelecting a milling cutter is not a simple task. There are many variables, opinions and lore to consider, but essentially the machinist is trying to choose a tool that will cut the material to the required specification for the least cost. The cost of the job is a combination of the price of the tool, the time taken by the milling machine, and the time taken by the machinist. Often, for jobs of a large number of parts, and days of machining time, the cost of the tool is lowest of the three costs.\nHistory.\nThe history of milling cutters is intimately bound up with that of milling machines. Milling evolved from rotary filing, so there is a continuum of development between the earliest milling cutters known, such as that of Jacques de Vaucanson from about the 1760s or 1770s, through the cutters of the milling pioneers of the 1810s through 1850s (Whitney, North, Johnson, Nasmyth, and others), to the cutters developed by Joseph R. Brown of Brown & Sharpe in the 1860s, which were regarded as a break from the past for their large step forward in tooth coarseness and for the geometry that could take successive sharpenings without losing the clearance (rake, side rake, and so on). De Vries (1910) reported, \"This revolution in the science of milling cutters took place in the States about the year 1870, and became generally known in Europe during the Exhibition in Vienna in 1873. However strange it may seem now that this type of cutter has been universally adopted and its undeniable superiority to the old European type is no longer doubted, it was regarded very distrustfully and European experts were very reserved in expressing their judgment. Even we ourselves can remember that after the coarse pitched cutter had been introduced, certain very clever and otherwise shrewd experts and engineers regarded the new cutting tool with many a shake of the head. When[,] however, the Worlds Exhibition at Philadelphia in 1876, exhibited to European experts a universal and many-sided application of the coarse pitched milling cutter which exceeded even the most sanguine expectations, the most far-seeing engineers were then convinced of the immense advantages which the application of the new type opened up for the metalworking industry, and from that time onwards the American type advanced, slowly at first, but later on with rapid strides\".\nWoodbury provides citations of patents for various advances in milling cutter design, including irregular spacing of teeth (1867), forms of inserted teeth (1872), spiral groove for breaking up the cut (1881), and others. He also provides a citation on how the introduction of vertical mills brought about wider use of the endmill and fly cutter types.\nScientific study by Holz and De Leeuw of the Cincinnati Milling Machine Company made the teeth even coarser and did for milling cutters what F.W. Taylor had done for single-point cutters with his famous scientific cutting studies.", "Engineering,_Manufacturing": 0.9998863935, "qwen": "Yes"}
{"id": "2389950", "revid": "17619453", "url": "https://en.wikipedia.org/wiki?curid=2389950", "title": "Engineer's spirit level", "text": "An engineer's spirit level (or machinist's level) is generally used to level machines, although they may also be used to level large workpieces on machines such as planers. Using gravity as a reference and checking a machine's axis of travel at several points, the level is used to ensure the machine's axis is \"straight\". A perfectly level machine does not actually need to be achieved, unless the particular manufacturing process requires it. Spirit levels are also used in building construction by carpenters and masons.\nThe upper image is a \"plain\" precision level used in the engineering field to level machines or workpieces; the lower image shows an adjustable precision level that has an accuracy of 1:10000. The adjustable nature of this level can also be used to measure the inclination of an object. \nThe accuracy of a spirit level can be checked by placing it on any flat surface, marking the bubble's position and rotating the level 180°. The position of the bubble should then be symmetrical to the first reading. Machinist's levels provide screw mechanisms to center the bubbles.\nSome levels have V grooves machined along their bases, enabling the level to sit on a round bar while remaining parallel with the bar's axis. They also have smaller cross levels to enable the second axes to be roughly checked or corrected and to ensure the primary axes' bubbles are at the tops of the vials.\nA precision level (1:24000) is used to check the installation of precision machine tools in two axes. A lathe is manufactured with its base in a level plane and if it is not installed level distortions in the frame cause machining errors. Small milling machines are often roughly leveled but large mills are installed level. A worn lathe may have a twist introduced to the machine's bed to ensure that it turns parallel to the spindle axis, by twisting the bed (that is worn) to the spindle axis. A lathe has several leveling screws. Usually, such a fix has limited utility for only part of the cutting tool (carriage) travel. A lathe usually requires two or more leveling trials as the machine castings \"settle into\" the adjustments.", "Engineering,_Manufacturing": 0.9999572039, "qwen": "Yes"}
{"id": "59617340", "revid": "38788892", "url": "https://en.wikipedia.org/wiki?curid=59617340", "title": "Implant resistance welding", "text": "Implant resistance welding is a method used in welding to join thermoplastics and thermoplastic composites. \nResistive heating of a conductive material implanted in the thermoplastic melts the thermoplastic while a pressure is applied in order to fuse two parts together. The process settings such as current and weld time are important, because they affect the strength of the joint. The quality of a joint made using implant resistance welding is determined using destructive strength testing of specimens.\nApplications.\nImplant resistance welding is used to joint thermoplastic composite components in the aerospace industry. For example, PEEK and PEI Laminate components for use in U.S. Air Force aircraft and a GF-PPS component on the Airbus A380 are joined using implant resistance welding. Electrofusion welding is a specific type of implant resistance welding used to join pipes.\nProcess.\nDuring the implant resistance welding process, current is applied to a heating element implanted in the joint. This current flowing through the implant produces heat through electrical resistance, which melts the matrix. Pressure is applied to push the parts together and molecular diffusion occurs at the melted surfaces of the parts, creating a joint.\nImplants.\nImplants serve as the source of heat to melt the thermoplastic. The heat is created through resistive heating as a current is applied to the implant. Two common types of implants are carbon fiber and stainless-steel mesh.\nCarbon Fiber.\nThe carbon fiber type implants can be further separated into unidirectional and fabric type implants. The unidirectional type carbon fibers do not transfer heat across the fibers easily, therefore, the carbon fiber fabric works better to evenly heat the entire surface. This difference affects the performance of the resulting weld, the welded joints using the carbon fiber fabric can have 69% higher shear strength and 179% more interlaminar fracture toughness, when compared to unidirectional carbon fibers. For carbon fiber reinforced thermoplastics, the carbon fiber heating element matches the reinforcing material, avoiding the introduction of a new material.\nStainless Steel Mesh.\nWelded joints with stainless steel mesh implants tend to have higher strength than welds using carbon fiber implants and results in less air trapped in the joint. Stainless steel wire can be placed in between two layers of resin, to avoid leaving spaces in the holes of the mesh. However, there are reasons to avoid using stainless steel in favor of carbon fiber including, increased weight, the metal acts as a contaminant, possibility of stress concentrations, and possibility of corrosion.\nEnergy Input.\nThe amount of energy input into the system (E) depends on the resistance of the heating elements (R), the current applied to the heating elements (I), and the amount of time the current is applied (t). Alternating current (AC) and direct current (DC) both work in this process. The energy produced is calculated using the following equation:\nformula_1\nResearch has shown the input variable with the most impact on the performance of the resulting joint is the current. The same amount of energy can by input into the part by applying a low current for a long period of time or if a high current is applied for a short amount of time. In general, a higher shear strength of the joint is achieved using the method with a higher current for a shorter time. Longer heating times at lower currents do not heat the joint surface as evenly. This can lead to the fiber reinforcement to move within the melted matrix. If the current is too high, however, it can result in residual stresses and warpage.\nFor a given constant electrical power, the temperature of the material surrounding the implants is directly dependent on the weld time. The longer weld time, yields a higher temperature. The lapped shear strength and the weld time are also correlated. Initially, there is a positive correlation between weld time and strength. However, the strength peaks for a certain weld time, and beyond this optimal weld time, the strength decreases.\nPressure.\nPressure is applied to the joining surfaces to prevent deconsolidation, allow intermolecular diffusion, and push air out of the joint. The pressure can be applied using displacement or pressure control. Pressure also ensures good contact between the implant and the bulk material, in order to increase electrical resistance. The pressure on the implant must create good contact without being so high that it severs the implant. This is achieved with pressures of 4 to 20 MPa for carbon fiber and 2 MPa for stainless steel mesh heating elements.\nStrength Testing.\nLap shear strength (LSS) testing, in accordance with ASTM D 1002, is a method of destructive testing used to determine the strength of electrofusion welds of thermoplastic composite materials. For this test, two rectangular samples of the composite are lapped at the ends and joined at the lap interface using resistance implant welding. Then, a tension strength test is performed on the welded sample, with the joint surface being loaded in pure shear, a load frame machine pulls the sample until failure and measures the maximum load. The lap shear strength  is the maximum tensile load imparted on the sample by the machine divided by the lapped area.\nFailure Modes.\nInterfacial failure or tearing is when the resin or laminate in immediate contact with the heating element on either side is pulled away, leaving the mesh or fabric heating element exposed. This type of failure is associated with low LSS of the sample and can occur as a result of inadequate heat input into the weld. \nAnother failure mode associated with low LSS is cohesive failure, which is a failure of the welded material, either the melted base material or resin surrounding the mesh. Cohesive failure is observed in samples with too much heat input during welding, which deteriorates the thermoplastic. Samples with high LSS generally fail due to debonding of the reinforcing fiber-matrix surface or other base material failure, known as intralaminar failure.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "38892441", "revid": "1165366159", "url": "https://en.wikipedia.org/wiki?curid=38892441", "title": "Solid Concepts", "text": "Solid Concepts, Inc. is a custom manufacturing company engaged in engineering, manufacturing, production, and prototyping. The company is headquartered in Valencia, California, in the Los Angeles County area, with six other facilities located around the United States. Solid Concepts is an additive manufacturing service provider as well as a major manufacturer of business products, aerospace, unmanned systems, medical equipment and devices, foundry cast patterns, industrial equipment and design, and transportation parts.\nThe company was founded in 1991, in the birthplace of Stereolithography. The company derives its name from its original focus on rapid prototyping through 3D printing (or additive manufacturing) with the idea that virtual concepts can be printed into solid reality, as the technologies that founded the company are capable of directly reading CAD data and creating parts. Solid Concepts markets its products under its main name, as well as under the website-only offshoot company called ZoomRP.com. The Solid Concepts logo originally featured layered lines comprising a \"S\" beside a \"C\" to represent layered manufacturing, but has since removed the layered lines, in order to better represent its composite, urethane, and tooling capabilities.\nOrigins and history.\nSolid Concepts Inc. was founded by former 3D Systems engineers Joe Allison, Schuyler Mitchell, and Ray Bradford in 1991. The company began with two SLA-250 Stereolithography machines. They moved into CNC machining, Selective Laser Sintering, and composites within a few years after opening, and have since gained PolyJet, Z-Corp 3D Colored Printing, Fused Deposition Modeling, Direct Metal Laser Sintering, urethanes and tooling and injection molding processes. Solid Concepts expanded throughout the United States, especially during the late 1990s early 2000s, opening facilities in Austin, TX, during the rise of Selective Laser Sintering; Poway, CA, during significant advances in Urethane technology with a strong focus on medical equipment; and Phoenix, AZ.\nJoe Allison has since been awarded the Distinguished Innovator Operator Awards, known as DINOs (formerly known as the Dinosaur Awards) by the Additive Manufacturing Users Group (AMUG) for innovation in laser sintering technology. The awards honor additive manufacturing expertise. In 2001, Solid Concepts hired former AARK employee Jeff Lemker, who headed the evolution of cast urethane products at the company. Lemker forged the path for QuantumCast™ Cast Urethanes, a proprietary casting process trademarked by the company. The process involves heat and pressure to enhance the properties of the urethanes during casting. The casting process has found use in the medical industry. In 2008, Solid Concepts branded and trademarked ID-Light, which is a method of printing SLA and FDM parts that is 1/12 the weight of regular SLA and FDM parts. The process has allowed lighter props for movies involving huge set pieces, such as the robots in \"Real Steel\". Solid Concepts was ranked in the top twenty manufacturing companies in the greater San Fernando Valley by San Fernando Business Journal in 2007. In 2013, the company was awarded a Platinum Source Preferred Supplier by Northrop Grumman. In 2013, the National Additive Manufacturing Innovation Institute (NAMII) recognized a FDM 3D Printed duct manufactured by Solid Concepts. The air duct has been awarded a place in the visitors center at the facility with the purpose of immersing visitors in the evolution of additive manufacturing technology.\nIn late 2013, the company demonstrated a 3D printed version of an M1911 pistol made of metal, the 1911DMLS, using an industrial 3D printer.\nAcquisitions.\nIn 2006, Solid Concepts acquired a model shop from Raytheon in Tucson, AZ, thus beginning their tooling and molding department. In 2008, Solid Concepts purchased former composites manufacturing company, Composite Tooling Technologies, to further develop a composites line. The acquisition facilitated a $1 million project for large MRI equipment, manufactured by Solid Concepts.\nOn April 2, 2014, Stratasys announced that they had entered into definitive agreements to acquire Solid Concepts and Harvest Technologies, which will be combined with RedEye, its existing digital manufacturing service business, to establish a single additive manufacturing services business unit. The acquisition was finalized on July 15, 2014.\nProducts and technologies.\nSolid Concepts manufactures products for a range of industries, including aerospace, business consumer, medical, and transportation. The company manufactures architectural models, prototypes, anatomical models, and investment casting patterns for metal castings using QuickCast SLA. The company largely focused on prototypes during their early years, but have since branched out to manufacture large composite equipment for industrial use, tooling and injection molding, end-use cast urethanes, metals and a range of high quality plastics.\nSolid Concepts offers the services of 3D Printing, composites, urethanes, tooling and injection molding rather than selling machines and equipment. Their additive manufacturing services include Stereolithography (SLA), PolyJet, Z-Corp Color 3D Prints, Fused Deposition Modeling (FDM), Direct Metal Laser Sintering (DMLS), and Selective Laser Sintering (SLS). The company also provides Computer Numerical Controlled (CNC) machining, composites, advanced cast urethanes, and injection molding and tooling.\nApplications and industries.\nSolid Concepts' services are utilized during early prototyping and design, market testing, and low to mass volume production. Solid Concepts' material offerings include durable thermoplastics, resins, nylons, and metals for uses ranging from large components and ducts in aerospace to RF Transparency protective equipment in the medical industry.\nIndustry specific applications include:\nHeadquarters.\nHeadquartered in Valencia, California, near the beginnings of the Angeles National Forest, Solid Concepts also has manufacturing facilities in Troy, Michigan, Austin, Texas, Phoenix and Tucson, Arizona, and Poway, California, and a partnership in China.\nManufacturing.\nSolid Concepts manufactures all products in house.", "Engineering,_Manufacturing": 0.9996557236, "qwen": "Yes"}
{"id": "38899596", "revid": "25254441", "url": "https://en.wikipedia.org/wiki?curid=38899596", "title": "Transfer line", "text": "A transfer line is a manufacturing system which consists of a predetermined sequence of machines connected by an automated material handling system and designed for working on a very small family of parts. Parts can be moved singularly because there’s no need for batching when carrying parts between process stations (as opposed to a job shop for example). The line can synchronous, meaning that all parts advance with the same speed, or asynchronous, meaning buffers exist between stations where parts wait to be processed. Not all transfer lines must geometrically be straight lines, for example circular solutions have been developed which make use of rotary tables, however using buffers becomes almost impossible.\nA crucial problem for this production system is that of line balancing: a trade-off between increasing productivity and minimizing cost conserving total processing time.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "5652552", "revid": "1163084062", "url": "https://en.wikipedia.org/wiki?curid=5652552", "title": "1977–78 UEFA Cup", "text": "The 1977–78 UEFA Cup was won by PSV Eindhoven on aggregate over Bastia.\nThe third club was revoked to Hungary and Romania, and it was assigned to Switzerland and Poland.\nFirst round.\nFirst leg.\n\"UEFA invalidated this game and awarded a 3–0 victory to Schalke 04 as Fiorentina fielded an ineligible player, Gianfranco Casarsa.\"\nSecond leg.\n\"Eintracht Frankfurt won 5–0 on aggregate.\"\n\"AZ Alkmaar won 16–1 on aggregate.\"\n\"Aston Villa won 6–0 on aggregate.\"\n\"Barcelona won 8–2 on aggregate.\"\n\"Bastia won 5–3 on aggregate.\"\n\"Bayern Munich won 12–0 on aggregate.\"\n\"Lazio won 5–1 on aggregate.\"\n\"Newcastle United won 4–0 on aggregate.\"\n\"Carl Zeiss Jena won 6–5 on aggregate.\"\n\"KB won 3–1 on aggregate.\"\n\"Schalke 04 won 5–1 on aggregate.\"\n\"Grasshoppers won 8–1 on aggregate.\"\n\"PSV Eindhoven won 11–2 on aggregate.\"\n\"Górnik Zabrze won 5–3 on aggregate.\"\n\"Dinamo Tbilisi won 1–0 on aggregate.\"\n\"1–1 on aggregate, Eintracht Braunschweig won on away goals.\"\n\"Ipswich Town won 6–0 on aggregate.\"\n\"Las Palmas won 8–4 on aggregate.\"\n\"Lens won 4–3 on aggregate.\"\n\"Újpest won 9–3 on aggregate.\"\n\"Magdeburg won 3–2 on aggregate.\"\n\"Dinamo Zagreb won 6–4 on aggregate.\"\n\"2–2 on aggregate, Widzew Łódź won on away goals rule.\"\n\"Marek Dupnitsa won 3–2 on aggregate.\"\n\"Inter Bratislava won 3–1 on aggregate.\"\n\"R.W.D. Molenbeek won 2–1 on aggregate.\"\n\"Athletic Bilbao won 2–1 on aggregate.\"\n\"3–3 on aggregate, Standard Liège won on away goals rule.\"\n\"Start won 8–0 on aggregate.\"\n\"AEK Athens won 3–1 on aggregate.\"\n\"Torino won 4–1 on aggregate.\"\n\"Zürich won 2–1 on aggregate.\"\nSecond round.\nSecond leg.\n\"Standard Liège won 6–3 on aggregate.\"\n\"2–2 on aggregate, Barcelona won in a penalty shoot-out.\"\n\"Aston Villa won 3–1 on aggregate.\"\n\"Bastia won 5–2 on aggregate.\"\n\"Bayern Munich won 3–2 on aggregate.\"\n\"Grasshoppers won 5–2 on aggregate.\"\n\"Ipswich Town won 4–3 on aggregate.\"\n\"Dinamo Tbilisi won 6–2 on aggregate.\"\n\"Lens won 6–2 on aggregate.\"\n\"Magdeburg won 7–3 on aggregate.\"\n\"2–2 on aggregate, Carl Zeiss Jena won in a penalty shoot-out.\"\n\"Eintracht Braunschweig won 4–1 on aggregate.\"\n\"Torino won 3–2 on aggregate.\"\n\"Athletic Bilbao won 3–2 on aggregate.\"\n\"PSV Eindhoven won 6–3 on aggregate.\"\n\"Eintracht Frankfurt won 7–3 on aggregate.\"\nThird round.\nSecond leg.\n\"Aston Villa won 3–1 on aggregate.\"\n\"Bastia won 5–3 on aggregate.\"\n\"Carl Zeiss Jena won 4–1 on aggregate.\"\n\"Eintracht Frankfurt won 6–1 on aggregate.\"\n\"3–3 on aggregate, Barcelona won in a penalty shoot-out.\"\n\"Magdeburg won 4–2 on aggregate.\"\n\"PSV Eindhoven won 4–1 on aggregate.\"\n\"Grasshoppers won 4–1 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"Barcelona won 4–3 on aggregate.\"\n\"Bastia won 9–6 on aggregate.\"\n\"PSV Eindhoven won 4–3 on aggregate.\"\n\"3–3 on aggregate, Grasshoppers won on away goals rule.\"\nSemi-finals.\nSecond leg.\n\"3–3 on aggregate, Bastia won on away goals rule.\"\n\"PSV won 4–3 on aggregate.\"\nFinal.\nSecond leg.\n\"PSV Eindhoven won 3–0 on aggregate\"", "Engineering,_Manufacturing": 1.0000052452, "qwen": "Yes"}
{"id": "5652753", "revid": "30380342", "url": "https://en.wikipedia.org/wiki?curid=5652753", "title": "1976–77 UEFA Cup", "text": "The 1976–77 UEFA Cup was the sixth season of the UEFA Cup, a club football competition organised by UEFA (the Union of European Football Associations). It was won by Italian club Juventus, who beat Athletic Bilbao of Spain in the two-legged final; both sides won one leg of the tie, which finished 2–2 on aggregate, but Juventus' solitary goal in the second leg at San Mamés Stadium in Bilbao saw them win on away goals. It was the first time that a team from Southern Europe had won the competition.\nFirst round.\nSecond leg.\n\"Schalke 04 won 5–4 on aggregate.\"\n\"Slovan Bratislava won 8–0 on aggregate.\"\n\"Basel won 5–3 on aggregate.\"\n\"Kaiserslautern won 11–1 on aggregate.\"\n\"AEK Athens won 3–2 on aggregate.\"\n\"Manchester United won 2–1 on aggregate.\"\n\"Austria Salzburg won 5–2 on aggregate.\"\n\"Barcelona won 5-4 on aggregate.\"\n\"Wisła Kraków won 4-2 on aggregate.\"\n\"Derby County won 16–1 on aggregate.\"\n\"Milan won 2–1 on aggregate.\"\n\"Eintracht Braunschweig won 7–1 on aggregate.\"\n\"Espanyol won 4–3 on aggregate.\"\n\"Feyenoord won 4–2 on aggregate.\"\n\"Videoton won 5–2 on aggregate.\"\n\"Grasshoppers won 9–0 on aggregate.\"\n\"Hibernian won 1–0 on aggregate.\"\n\"Budapest Honvéd won 2–1 on aggregate.\"\n\"Köln won 3–1 on aggregate.\"\n\"Öster won 4–3 on aggregate.\"\n\"Magdeburg won 4–3 on aggregate.\"\n\"Juventus won 2–1 on aggregate.\"\n\"Molenbeek won 7–0 on aggregate.\"\n\"Queens Park Rangers won 11–0 on aggregate.\"\n\"Lokeren won 6–1 on aggregate.\"\n\"Akademik Sofia won 3–2 on aggregate.\"\n\"Shakhtar Donetsk won 4–1 on aggregate.\"\n\"Sportul Studențesc won 4–2 on aggregate.\"\n\"Wacker Innsbruck won 7–1 on aggregate.\"\n\"Dinamo Zagreb won 4–0 on aggregate.\"\n\"Athletic Bilbao won 5–1 on aggregate.\"\n\"Red Star Belgrade won 5–3 on aggregate.\"\nSecond round.\nSecond leg.\n\"AEK Athens won 5–2 on aggregate.\"\n\"Milan won 5–4 on aggregate.\"\n\"2–2 on aggregate; Red Star Belgrade won on away goals.\"\n\"Barcelona won 3–2 on aggregate.\"\n\"Athletic Bilbao won 4–2 on aggregate.\"\n\"Espanyol won 3–2 on aggregate.\"\n\"Öster won 4–3 on aggregate.\"\n\"Videoton won 2–1 on aggregate.\"\n\"Feyenoord won 7–2 on aggregate.\"\n\"Köln won 5–2 on aggregate.\"\n\"Magdeburg won 4–2 on aggregate.\"\n\"Juventus won 3–1 on aggregate.\"\n\"Shakhtar Donetsk won 6–2 on aggregate.\"\n\"Queens Park Rangers won 8–5 on aggregate.\"\n\"Schalke 04 won 5–0 on aggregate.\"\n\"2–2 on aggregate; Molenbeek won 5–4 on penalties.\"\nThird round.\nSecond leg.\n\"3–3 on aggregate; AEK Athens won on away goals.\"\n\"Athletic Bilbao won 5–4 on aggregate.\"\n\"Feyenoord won 3–0 on aggregate.\"\n\"Juventus won 3–1 on aggregate.\"\n\"Magdeburg won 5–1 on aggregate.\"\n\"Barcelona won 8–1 on aggregate.\"\n\"4–4 on aggregate; Queens Park Rangers won on away goals.\"\n\"Molenbeek won 2–1 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"Athletic Bilbao won 4–3 on aggregate.\"\n\"Molenbeek won 2–1 on aggregate.\"\n\"Juventus won 4–1 on aggregate.\"\n\"3–3 on aggregate; AEK Athens won 7–6 on penalties.\"\nSemi-finals.\nSecond leg.\n\"1–1 on aggregate; Athletic Bilbao won on away goals.\"\n\"Juventus won 5–1 on aggregate.\"\nFinal.\nSecond leg.\n\"2–2 on aggregate; Juventus won on away goals.\"", "Engineering,_Manufacturing": 1.0000014305, "qwen": "Yes"}
{"id": "5653012", "revid": "29221587", "url": "https://en.wikipedia.org/wiki?curid=5653012", "title": "1975–76 UEFA Cup", "text": "The 1975–76 UEFA Cup was won by Liverpool over Club Brugge on aggregate.\nThe third club was revoked from the Netherlands and Austria, and it was assigned to the Soviet Union and Sweden.\nFirst round.\nSecond leg.\n\"Both legs were played in West Germany, MSV Duisburg won 10–3 on aggregate.\"\n\"Ajax won 14–1 on aggregate.\"\n\"4–4 on aggregate; Real Sociedad won on away goals.\"\n\"Barcelona won 6–2 on aggregate.\"\n\"Spartak Moscow won 2–1 on aggregate.\"\n\"Royal Antwerp won 5–1 on aggregate.\"\n\"Budapest Honvéd won 3–2 on aggregate.\"\n\"Carl Zeiss Jena won 4–0 on aggregate.\"\n\"Red Star Belgrade won 4–2 on aggregate.\"\n\"Milan won 1–0 on aggregate.\"\n\"Ipswich Town won 4–1 on aggregate.\"\n\"Śląsk Wrocław won 5–4 on aggregate.\"\n\"Hertha BSC won 6–2 on aggregate.\"\n\"Liverpool won 3–2 on aggregate.\"\n\"Stal Mielec won 3–1 on aggregate.\"\n\"Köln won 5–2 on aggregate.\"\n\"Club Brugge won 6–4 on aggregate.\"\n\"Öster won 6–1 on aggregate.\"\n\"Dynamo Dresden won 6–3 on aggregate.\"\n\"Lazio won 3–1 on aggregate.\"\n\"Porto won 10–0 on aggregate.\"\n\"Galatasaray won 3–2 on aggregate.\"\n\"Roma won 2–1 on aggregate.\"\n\"Torpedo Moscow won 5–2 on aggregate.\"\n\"Vasas SC won 4–2 on aggregate.\"\n\"AEK Athens won 3–1 on aggregate.\"\n\"Hamburg won 4–2 on aggregate.\"\n\"Athlone Town won 4–2 on aggregate.\"\n\"Inter Bratislava won 8–2 on aggregate.\"\n\"Dundee United won 6–0 on aggregate.\"\n\"Levski-Spartak Sofia won 7–1 on aggregate.\"\n\"Sporting CP won 5–2 on aggregate.\"\nSecond round.\nFirst leg.\n\"Lazio refused to play for security reasons, claiming it would be impossible to play due to political demonstrations following the execution in Spain of five ETA and FRAP members on 27 September on terrorism charges. UEFA awarded Barcelona a 3–0 victory, ruling those three goals were not applicable for the away goals rule.\"\nSecond leg.\n\"4–4 on aggregate; Levski-Spartak Sofia won on away goals.\"\n\"Milan won 3–0 on aggregate.\"\n\"1–1 on aggregate; Stal Mielec won on penalties.\"\n\"Porto won 3–2 on aggregate.\"\n\"Torpedo Moscow won 7–2 on aggregate.\"\n\"Ajax won 4–2 on aggregate.\"\n\"Dynamo Dresden won 3–2 on aggregate.\"\n\"3–3 on aggregate; Inter Bratislava won on away goals.\"\n\"Club Brugge won 4–3 on aggregate.\"\n\"Spartak Moscow won 3–0 on aggregate.\"\n\"Roma won 2–1 on aggregate.\"\n\"Liverpool won 9–1 on aggregate.\"\n\"Hamburg won 5–1 on aggregate.\"\n\"Śląsk Wrocław won 3–2 on aggregate.\"\n\"Vasas SC won 4–3 on aggregate.\"\n\"Before the game, Johan Cruyff was given his Ballon d'Or award for the 1974 season.\"\n\"Barcelona won 7–0 on aggregate.\"\nThird round.\nSecond leg.\n\"3–3 on aggregate; Levski-Spartak Sofia won on penalties.\"\n\"Barcelona won 4–1 on aggregate.\"\n\"Club Brugge won 2–0 on aggregate.\"\n\"Dynamo Dresden won 4–3 on aggregate.\"\n\"Hamburg won 3–2 on aggregate.\"\n\"Stal Mielec won 2–1 on aggregate.\"\n\"Liverpool won 5–1 on aggregate.\"\n\"Milan won 4–2 on aggregate.\"\nQuarter–finals.\nSecond leg.\n\"Barcelona won 8–5 on aggregate.\"\n\"Club Brugge won 3–2 on aggregate.\"\n\"Liverpool won 2–1 on aggregate.\"\n\"Hamburg won 2–1 on aggregate.\"\nSemi–finals.\nSecond leg.\n\"Liverpool won 2–1 on aggregate.\"\n\"Club Brugge won 2–1 on aggregate.\"\nFinal.\nSecond leg.\n\"Liverpool won 4–3 on aggregate.\"", "Engineering,_Manufacturing": 0.9992469549, "qwen": "Yes"}
{"id": "5653340", "revid": "30380342", "url": "https://en.wikipedia.org/wiki?curid=5653340", "title": "1974–75 UEFA Cup", "text": "The 1974–75 UEFA Cup was won by Borussia Mönchengladbach over Twente on aggregate.\nThe third club was revoked to Scotland and Belgium, and it was assigned to the Netherlands and Austria.\nFirst round.\nSecond leg.\n\"Lyon won 11–1 on aggregate.\"\n\"Portadown won 2–1 on aggregate.\"\n\"Derby County won 6–2 on aggregate.\"\n\"3–3 on aggregate, Twente won on away goals rule.\"\n\"1–1 on aggregate, Ajax won on away goals rule.\"\n\"RWD Molenbeek won 5–2 on aggregate.\"\n\"Hibernian won 12–3 on aggregate.\"\n\"Porto won 5–4 on aggregate.\"\n\"Inter Milan won 3–0 on aggregate.\"\n\"Partizan won 5–2 on aggregate.\"\n\"Djurgården won 7–1 on aggregate.\"\n\"Dinamo București won 4–0 on aggregate.\"\n\"3–3 on aggregate, Velež Mostar won on away goals rule.\"\n\"Steagul Roșu Brașov won 3–2 on aggregate.\"\n\"Borussia Mönchengladbach won 4–2 on aggregate.\"\n\"2–2 on aggregate, Royal Antwerp won on away goal rules.\"\n\"1–1 on aggregate, Dynamo Dresden won on away goal rules.\"\n\"Hamburg won 4–0 on aggregate.\"\n\"Rapid Wien won 3–2 on aggregate.\"\n\"Baník Ostrava won 5–0 on aggregate.\"\n\"4–4 on aggregate, Raba ETO Győr won 5–4 in penalty shoot-out.\"\n\"4–4 on aggregate, Dynamo Moscow won on away goals rule.\"\n\"Nantes won 3–2 on aggregate.\"\n\"Napoli won 3–1 on aggregate.\"\n\"Juventus won 4–2 on aggregate.\"\n\"Grasshopper won 3–2 on aggregate.\"\n\"Fortuna Düsseldorf won 4–2 on aggregate.\"\n\"Köln won 9–2 on aggregate.\"\n\"Both legs were played in Amsterdam, the second leg was formally a 'home' game for Hibernians. Amsterdam won 12–0 on aggregate.\"\n\"Atlético Madrid won 6–3 on aggregate.\"\n\"Real Zaragoza won 5–1 on aggregate.\"\nSecond round.\nSecond leg.\n\"4–4 on aggregate, Derby County won 7–6 in penalty shoot-out.\"\n\"Juventus won 8–2 on aggregate.\"\n\"Partizan won 6–1 on aggregate.\"\n\"Baník Ostrava won 2–1 on aggregate.\"\n\"Köln won 4–3 on aggregate.\"\n\"Fortuna Düsseldorf won 3–2 on aggregate.\"\n\"Velež Mostar won 2–1 on aggregate.\"\n\"1–1 on aggregate, Dynamo Dresden won 4–3 in penalty shoot-out.\"\n\"Real Zaragoza won 6–2 on aggregate.\"\n\"Borussia Mönchengladbach won 6–2 on aggregate.\"\n\"Hamburg won 10–1 on aggregate.\"\n\"Twente won 3–1 on aggregate.\"\n\"Dukla Prague won 5–1 on aggregate.\"\n\"Amsterdam won 2–1 on aggregate.\"\n\"Napoli won 2–0 on aggregate.\"\n\"2–2 on aggregate, Ajax won on away goals rule.\"\nThird round.\nSecond leg.\n\"Baník Ostrava won 3–1 on aggregate.\"\n\"Hamburg won 6–3 on aggregate.\"\n\"Twente won 6–3 on aggregate.\"\n\"Köln won 5–2 on aggregate.\"\n\"Borussia Mönchengladbach won 9–2 on aggregate.\"\n\"Amsterdam won 5–1 on aggregate.\"\n\"2–2 on aggregate; Juventus won on away goals.\"\n\"Velež Mostar won 5–4 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"Juventus won 2–0 on aggregate.\"\n\"Köln won 8–3 on aggregate.\"\n\"Twente won 2–1 on aggregate.\"\n\"Borussia Mönchengladbach won 4–1 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Twente won 4–1 on aggregate.\"\n\"Borussia Mönchengladbach won 4–1 on aggregate.\"\nFinal.\nSecond leg.\n\"Borussia Mönchengladbach won 5–1 on aggregate.\"", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "5653697", "revid": "30380342", "url": "https://en.wikipedia.org/wiki?curid=5653697", "title": "1972–73 UEFA Cup", "text": "The 1972–73 UEFA Cup was the second season of the UEFA Cup, a football competition organised by UEFA for clubs affiliated to its member associations. It was won by Liverpool, who beat Borussia Mönchengladbach over two legs in the final. The first leg was played at Anfield in Liverpool, where Liverpool won the match 3–0. Mönchengladbach won the second leg in Germany 2–0 for an aggregate score of 3–2.\nFirst round.\nSummary.\n1 Hvidovre walkover, HJK withdrew.\nMatches.\n\"Liverpool won 2–0 on aggregate.\"\n\"Norrköping won 4–1 on aggregate.\"\n\"Levski-Spartak won 6–5 on aggregate.\"\n\"AEK Athens won 4–2 on aggregate.\"\n\"Beroe Stara Zagora won 10–1 on aggregate.\"\n\"Twente won 4–2 on aggregate.\"\n\"Slovan Bratislava won 8–2 on aggregate.\"\n\"Ruch Chorzów won 3–1 on aggregate.\"\n\"Dynamo Dresden won 4–2 on aggregate.\"\n\"Red Star Belgrade won 7–4 on aggregate.\"\n\"OFK Beograd won 5–3 on aggregate.\"\n\"Tottenham Hotspur won 12–3 on aggregate.\"\n\"Viking won 1–0 on aggregate.\"\n\"Club Brugge won 6–5 on aggregate.\"\n\"Frem won 5–2 on aggregate.\"\n\"Budapest Honvéd won 4–0 on aggregate.\"\n\"Köln won 5–1 on aggregate.\"\n\"Borussia Mönchengladbach won 9–5 on aggregate.\"\n\"BFC Dynamo won 3–2 on aggregate.\"\n\"Feyenoord won 21–0 on aggregate.\"\n\"Valencia won 4–3 on aggregate.\"\n\"Grasshoppers won 4–2 on aggregate.\"\n\"Kaiserslautern won 5–3 on aggregate.\"\n\"Las Palmas won 4–2 on aggregate.\"\n\"Inter Milan won 7–1 on aggregate.\"\n\"Vitória de Setúbal won 6–2 on aggregate.\"\n\"Ararat Yerevan won 2–0 on aggregate.\"\n\"Fiorentina won 5–1 on aggregate.\"\n\"Olympiacos won 3–1 on aggregate.\"\n\"CUF Barreiro won 3–0 on aggregate.\"\n\"Porto won 4–1 on aggregate.\"\n\"Hvidovre walkover, HJK withdrew.\"\nSecond round.\nMatches.\n\"Köln won 9–2 on aggregate.\"\n\"Liverpool won 6–1 on aggregate.\"\n\"Beroe Stara Zagora won 3–1 on aggregate.\"\n\"BFC Dynamo won 3–2 on aggregate.\"\n\"Red Star Belgrade won 4–1 on aggregate.\"\n\"Kaiserslautern won 3–2 on aggregate.\"\n\"Dynamo Dresden won 4–0 on aggregate.\"\n\"Borussia Mönchengladbach won 6–1 on aggregate.\"\n\"Twente won 9–0 on aggregate.\"\n\"Ararat Yerevan won 7–3 on aggregate.\"\n\"5–5 on aggregate; OFK Beograd won on away goals.\"\n\"Tottenham Hotspur won 4–1 on aggregate.\"\n\"Inter Milan won 4–2 on aggregate.\"\n\"Las Palmas won 3–2 on aggregate.\"\n\"2–2 on aggregate; Vitória de Setúbal won on away goals.\"\n\"Porto won 5–3 on aggregate.\"\nThird round.\nMatches.\n\"Borussia Mönchengladbach won 5–0 on aggregate.\"\n\"Liverpool won 3–1 on aggregate.\"\n\"OFK Beograd won 3–1 on aggregate.\"\n\"2–2 on aggregate; Kaiserslautern won on penalties.\"\n\"Twente won 4–2 on aggregate.\"\n\"Tottenham Hotspur won 2–1 on aggregate.\"\n\"Dynamo Dresden won 3–1 on aggregate.\"\n\"Vitória de Setúbal won 2–1 on aggregate.\"\nQuarter-finals.\nMatches.\n\"Borussia Mönchengladbach won 9–2 on aggregate.\"\n\"Twente won 4–3 on aggregate.\"\n\"Liverpool won 3–0 on aggregate.\"\n\"2–2 on aggregate; Tottenham won on away goals.\"\nSemi-finals.\nMatches.\n\"2–2 on aggregate; Liverpool won on away goals.\"\n\"Borussia Mönchengladbach won 5–1 on aggregate.\"\nFinal.\nMatches.\n\"Liverpool won 3–2 on aggregate.\"", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "5656649", "revid": "14965160", "url": "https://en.wikipedia.org/wiki?curid=5656649", "title": "Spillage", "text": "In industrial production, spillage is the loss of production output due to production of a series of defective or unacceptable products which must be rejected. Spillage is an often costly event which occurs in manufacturing when a process degradation or failure occurs that is not immediately detected and corrected, and in which defective or reject product therefore continues to be produced for some extended period of time.\nSpillage results in costs due to lost production volume, excessive scrap, delayed delivery of product, and wastage of human and capital equipment resources. Minimization of the occurrence and duration of manufacturing spillage requires that closed-loop control and associated process monitoring and metrology functions be integrated into critical steps of the overall manufacturing process. The extent to which process control is complete and metrology is high resolution so as to be comprehensive determines the extent to which spillages will be prevented.", "Engineering,_Manufacturing": 0.9999836683, "qwen": "Yes"}
{"id": "5660157", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=5660157", "title": "Junk box", "text": " \nJunk box is a term used by amateur radio operators (hams) to describe a collection of spare parts and old equipment kept to assist in building and repairing their station. Typical items found in a junk box are electronic components such as resistors and capacitors as well as small parts such as screws, nuts and bolts. A junk box may also contain surplus, cast off or used electronic gear. Radio amateurs who construct their own equipment, known as homebrewers, often have large or well stocked junk boxes.\nDescription and uses.\nAccording to some hams, a well-stocked junk box is a requirement for anyone who likes to build, repair, or tinker with radio equipment and electronic gear. Keeping an ample supply of spare electronic components provides the ham with parts to build a variety of electronic projects, as well as \"spares\" of components needed for repairs. Resistors, capacitors, transistors, meters, speakers, wire, cable, and even small mechanical parts such as screws, nuts and bolts are typical junk box items. Cannibalizing or removing parts from old equipment is sometimes the only way for an individual to obtain some types of parts, either because they are no longer made, or can only be ordered in large quantities. Cast-off or used electronic equipment make especially good additions to a junk box. What non-hams may see as junk, hams often see as treasure. Hamfests, surplus stores, electronic swapmeets and even dumpster diving are often venues for hams to trade, buy, scrounge, or salvage spare parts and components. Junk boxes can range in size from small cardboard or plastic boxes, to large collections that fill garages and outbuildings. Many hams derive satisfaction from having an especially large junk box full of exotic and hard-to-find components. Others feel that the act of tracking down parts is half the fun.\nUse in homebrewing.\nHomebrewing is a slang term in amateur radio referring to building an alternative to a commercially available piece of equipment or accessory by hand. \"Homebrewers\" often naturally maintain a sizeable junk box, and amateur radio publications have often employed the term in DIY project articles such as \"The 'Junker' Amplifier\" from QST, Oct 1970, an RF amplifier built from scrounged and junk-box parts.", "Engineering,_Manufacturing": 0.9919452667, "qwen": "Yes"}
{"id": "5663760", "revid": "30000058", "url": "https://en.wikipedia.org/wiki?curid=5663760", "title": "Flat no-leads package", "text": "Flat no-leads packages such as quad-flat no-leads (QFN) and dual-flat no-leads (DFN) physically and electrically connect integrated circuits to printed circuit boards. Flat no-leads, also known as micro leadframe (MLF) and SON (small-outline no leads), is a surface-mount technology, one of several package technologies that connect ICs to the \"surfaces\" of PCBs without through-holes. Flat no-lead is a near chip scale plastic encapsulated package made with a planar copper lead frame substrate. Perimeter lands on the package bottom provide electrical connections to the PCB. Flat no-lead packages usually, but not always, include an exposed thermally conductive pad to improve heat transfer out of the IC (into the PCB). Heat transfer can be further facilitated by metal vias in the thermal pad. The QFN package is similar to the quad-flat package (QFP), and a ball grid array (BGA).\nFlat no-lead cross-section.\nThe figure shows the cross section of a flat no-lead package with a lead frame and wire bonding. There are two types of body designs, \"punch singulation\" and \"saw singulation\". Saw singulation cuts a large set of packages in parts. In punch singulation, a single package is moulded into shape. The cross section shows a saw-singulated body with an attached thermal head pad. The lead frame is made of copper alloy and a thermally conductive adhesive is used for attaching the silicon die to the thermal pad. The silicon die is electrically connected to the lead frame by 1–2 thou diameter gold wires.\nThe pads of a saw-singulated package can either be completely under the package, or they can fold around the edge of the package.\nDifferent types.\nTwo types of QFN packages are common: air-cavity QFNs, with an air cavity designed into the package, and plastic-moulded QFNs with air in the package minimized.\nLess-expensive plastic-moulded QFNs are usually limited to applications up to ~2–3 GHz. It is usually composed of just 2 parts, a plastic compound and copper lead frame, and does not come with a lid.\nIn contrast, the air-cavity QFN is usually made up of three parts; a copper leadframe, plastic-moulded body (open, and not sealed), and either a ceramic or plastic lid. It is usually more expensive due to its construction, and can be used for microwave applications up to 20–25 GHz.\nQFN packages can have a single row of contacts or a double row of contacts.\nAdvantages.\nThis package offers a variety of benefits including reduced lead inductance, a small sized \"near chip scale\" footprint, thin profile and low weight. It also uses perimeter I/O pads to ease PCB trace routing, and the exposed copper die-pad technology offers good thermal and electrical performance. These features make the QFN an ideal choice for many new applications where size, weight, thermal and electrical performance are important.\nDesign, manufacturing, and reliability challenges.\nImproved packaging technologies and component miniaturization can often lead to new or unexpected design, manufacturing, and reliability issues. This has been the case with QFN packages, especially when it comes to adoption by new non-consumer electronic OEMs.\nDesign and manufacturing.\nSome key QFN design considerations are pad and stencil design. When it comes to bond pad design two approaches can be taken: solder mask defined (SMD) or non-solder mask defined (NSMD). A NSMD approach typically leads to more reliable joints, since the solder is able to bond to both the top and sides of the copper pad. The copper etching process also generally has tighter control than the solder masking process, resulting in more consistent joints. This does have the potential to affect the thermal and electrical performance of the joints, so it can be helpful to consult the package manufacturer for optimal performance parameters. SMD pads can be used to reduce the chances of solder bridging, however this may affect overall reliability of the joints. Stencil design is another key parameter in QFN design process. Proper aperture design and stencil thickness can help produce more consistent joints (i.e. minimal voiding, outgassing, and floating parts) with proper thickness, leading to improved reliability.\nThere are also issues on the manufacturing side. For larger QFN components, moisture absorption during solder reflow can be a concern. If there is a large amount of moisture absorption into the package then heating during reflow can lead to excessive component warpage. This often results in the corners of the component lifting off the printed circuit board, causing improper joint formation. To reduce the risk of warpage issues during reflow a moisture sensitivity level of 3 or higher is recommended.\nSeveral other issues with QFN manufacturing include: part floating due to excessive solder paste under the center thermal pad, large solder voiding, poor reworkable characteristics, and optimization of the solder reflow profile.\nReliability.\nComponent packaging is often driven by the consumer electronics market with less consideration given to higher reliability industries such as automotive and aviation. It can therefore be challenging to integrate component package families, such as the QFN, into high reliability environments. QFN components are known to be susceptible to solder fatigue issues, especially thermomechanical fatigue due to thermal cycling. The significantly lower standoff in QFN packages can lead to higher thermomechanical strains due to coefficient of thermal expansion (CTE) mismatch as compared to leaded packages. For example, under accelerated thermal cycling conditions between -40 °C to 125 °C, various quad flat package (QFP) components can last over 10,000 thermal cycles whereas QFN components tend to fail at around 1,000-3,000 cycles.\nHistorically, reliability testing has been mainly driven by JEDEC, however this has primarily focused on die and 1st level interconnects. IPC-9071A attempted to address this by focusing on 2nd level interconnects (i.e. package to PCB substrate). The challenge with this standard is that it has been more adopted by OEMs than component manufacturers, who tend to view it as an application-specific issue. As a result there has been much experimental testing and finite element analysis across various QFN package variants to characterize their reliability and solder fatigue behavior.\nSerebreni et al. proposed a semi-analytical model to assess the reliability QFN solder joints under thermal cycling. This model generates effective mechanical properties for the QFN package, and calculates the shear stress and strain using a model proposed by Chen and Nelson. The dissipated strain energy density is then determined from these values and used to predict characteristic cycles to failure using a 2-parameter Weibull curve.\nComparison to other packages.\nThe QFN package is similar to the quad flat package, but the leads do not extend out from the package sides. It is hence difficult to hand-solder a QFN package, inspect solder joint quality, or probe lead(s).\nVariants.\nDifferent manufacturers use different names for this package: ML (micro-leadframe) versus FN (flat no-lead), in addition there are versions with pads on all four sides (quad) and pads on just two sides (dual), thickness varying between 0.9–1.0 mm for normal packages and 0.4 mm for extremely thin. Abbreviations include:\nMicro lead frame package (MLP) is a family of integrated circuit QFN packages, used in surface mounted electronic circuits designs. It is available in 3 versions which are MLPQ (Q stands for \"quad\"), MLPM (M stands for \"micro\"), and MLPD (D stands for \"dual\"). These package generally have an exposed die attach pad to improve thermal performance. This package is similar to chip scale packages (CSP) in construction. MLPD are designed to provide a footprint-compatible replacement for small-outline integrated circuit (SOIC) packages.\nMicro lead frame (MLF) is a near CSP plastic encapsulated package with a copper leadframe substrate. This package uses perimeter lands on the bottom of the package to provide electrical contact to the printed circuit board. The die attach paddle is exposed on the bottom of the package surface to provide an efficient heat path when soldered directly to the circuit board. This also enables stable ground by use of down bonds or by electrical connection through a conductive die attach material.\nA more recent design variation which allows for higher density connections is the \"dual row micro lead frame\" (DRMLF) package. This is an MLF package with two rows of lands for devices requiring up to 164 I/O. Typical applications include hard disk drives, USB controllers, and wireless LAN.", "Engineering,_Manufacturing": 1.000007391, "qwen": "Yes"}
{"id": "1386629", "revid": "44920675", "url": "https://en.wikipedia.org/wiki?curid=1386629", "title": "Gold plating", "text": "Gold plating is a method of depositing a thin layer of gold onto the surface of another metal, most often copper or silver (to make silver-gilt), by chemical or electrochemical plating. This article covers plating methods used in the modern electronics industry; for more traditional methods, often used for much larger objects, see gilding. \nTypes.\nThere are several types of gold plating used in the electronics industry:\nGold plating chemistry.\nThere are five recognized classes of gold plating chemistry:\nJewelry.\nGold plating of silver is used in the manufacture of jewelry. The thickness of gold plating on jewellery is noted in microns (or micro-meters). The microns of thickness determines how long the gold plating lasts with usage. The jewellery industry denotes different qualities of gold plating in the following terminology\nGold plated silver jewellery can still tarnish as the silver atoms diffuse into the gold layer, causing slow gradual fading of its color and eventually causing tarnishing of the surface. This process may take months and even years, depending on the thickness of the gold layer. A barrier metal layer is used to counter this effect - these can be nickel or rhodium. Copper, which also migrates into gold, does so more slowly than silver. The copper is usually further plated with nickel. A gold-plated silver article is usually a silver substrate with layers of copper, nickel, and gold deposited on top of it.\nInfrared reflectivity.\nGold, applied by evaporated methods or electroplating, has been specified by NASA to thermally control spacecraft instruments, due to its 99% reflectivity in infrared wavelengths.\nElectronics.\nGold plating is often used in electronics, to provide a corrosion-resistant electrically conductive layer on copper, typically in electrical connectors and printed circuit boards.\nWith direct gold-on-copper plating, the copper atoms tend to diffuse through the gold layer, causing tarnishing of its surface and formation of an oxide and/or sulphide layer.\nA layer of a suitable barrier metal, usually nickel, is often deposited on the copper substrate before the gold plating. The layer of nickel provides mechanical backing for the gold layer, improving its wear resistance. It also reduces the impact of pores present in the gold layer.\nBoth the nickel and gold layers can be plated by electrolytic or electroless processes. There are many factors to consider in selection of either electrolytic or electroless plating methods. These include what the deposit will be used for, configuration of the part, materials compatibility and cost of processing. In different applications, electrolytic or electroless plating can have cost advantages.\nAt higher frequencies, the skin effect may cause higher losses due to higher electrical resistance of nickel; a nickel-plated trace can have its useful length shortened three times in the 1 GHz band in comparison with the non-plated one. Selective plating is used, depositing the nickel and gold layers only on areas where it is required and does not cause the detrimental side effects.\nGold plating may lead to formation of gold whiskers.\nWire bonding between gold plated contacts and aluminium wires or between aluminium contacts and gold wires under certain conditions develops a brittle layer of gold-aluminium intermetallics, known as purple plague.\nSoldering issues.\nSoldering gold-plated parts can be problematic as gold is soluble in solder. Solder which contains more than 4–5% gold can become brittle. The joint surface is dull-looking.\nGold reacts with both tin and lead in their liquid state, forming brittle intermetallics. When eutectic 63% tin – 37% lead solder is used, no lead-gold compounds are formed, because gold preferentially reacts with tin, forming the compound. Particles of disperse in the solder matrix, forming preferential cleavage planes, significantly lowering the mechanical strength and therefore reliability of the resulting solder joints.\nIf the gold layer does not completely dissolve into the solder, then slow intermetallic reactions can proceed in the solid state as the tin and gold atoms cross-migrate. Intermetallics have poor electrical conductivity and low strength. The ongoing intermetallic reactions also cause Kirkendall effect, leading to mechanical failure of the joint, similar to the degradation of gold-aluminium bonds known as purple plague.\nA 2–3 µm layer of gold dissolves completely within one second during typical wave soldering conditions. Layers of gold thinner than 0.5 µm (0.02 thou) also dissolve completely into the solder, exposing the underlying metal (usually nickel) to the solder. Impurities in the nickel layer can prevent the solder from bonding to it. Electroless nickel plating contains phosphorus. Nickel with more than 8% phosphorus is not solderable. Electrodeposited nickel may contain nickel hydroxide. An acid bath is required to remove the passivation layer before applying the gold layer; improper cleaning leads to a nickel surface difficult to solder. A stronger flux can help, as it aids dissolving the oxide deposits. Carbon is another nickel contaminant that hinders solderability.", "Engineering,_Manufacturing": 0.9994114637, "qwen": "Yes"}
{"id": "1387022", "revid": "39191556", "url": "https://en.wikipedia.org/wiki?curid=1387022", "title": "Swaging", "text": "Swaging  is a forging process in which the dimensions of an item are altered using dies into which the item is forced. Swaging is usually a cold working process, but also may be hot worked.\nThe term swage may apply to the process (verb) or to a die or tool (noun) used in that process.\nOrigin.\nThe term \"swage\" comes from the Old French term , meaning \"decorative groove\" or \"ornamental moulding\". Swages were originally tools used by blacksmiths to form metal into various shapes too intricate to make with a hammer alone. These have handles for holding or pegs for attaching to an anvil, and often a flat head for striking with a hammer. Swage blocks are anvil-like dies with various shapes forged into them, which are also used for forming metal. Swages called \"fullers\" are specific to making grooves in swords and knives.\n\"Swage\" is most often pronounced (AHD format: swāj). Another (less common) pronunciation sometimes heard in the metalworking industries is (AHD format: swĕj) (perhaps influenced by \"sledge\" as in \"sledgehammer\").\nProcess.\nAs a general manufacturing process swaging may be broken up into two categories:\nTubes may be tagged (reduced in diameter to enable the tube to be initially fed through the die to then be pulled from the other side) using a rotary swager, which allows them to be drawn on a draw bench. Swaging is normally the method of choice for precious metals since there is no loss of material in the process.\nRotary swaging is usually a cold working process, used to reduce the diameter, produce a taper, or add a point to a round workpiece. It can also impart internal shapes in hollow workpieces through the use of a mandrel (the shape must have a constant cross-section). Swaging a bearing into a housing means either flaring its groove's lips onto the chamfer of the housing, or flaring the housing's material over the edge of the bearing. The flaring is done with a pair of rolls that travel around the hole and are fed down into the part, deforming the metal in a controlled, predicted way. Grease is often used to lubricate this swaging process, which is also called \"roller swaging\".\nA swaging machine works by using two or four split dies which separate and close up to 2,000 times a minute. This action is achieved by mounting the dies into the machine's spindle which is rotated by a motor. The spindle is mounted inside a cage containing rollers (looks like a roller bearing). The rollers are larger than the cage so as the spindle spins the dies are pushed out to ride on the cage by centrifugal force, as the dies cross over the rollers they push the dies together because of their larger size. On a four-die machine, the number of rollers cause all dies to close at a time; if the number of rollers do not cause all pairs of dies to close at the same time then the machine is called a rotary forging machine, even though it is still a swaging process.\nA variation of the rotary swager is the \"creeping spindle\" swaging machine where both the spindle and cage revolve in opposite directions, this prevents the production of fins between the dies where the material being swaged grows up the gap between the dies.\nThere are two basic types of rotary swaging machine, the standard (also known as a tagging machine), and the \"butt swaging\" machine. A butt swaging machine works by having sets of wedges that close the dies onto the workpiece by inserting them between the annular rollers and the dies, normally by the use of a foot pedal. A butt swaging machine can allow a workpiece to be inserted without the dies closing on it, for example a workpiece can be inserted and then the dies closed, drawn through until remain and the dies are then released, the finished workpiece would then, for example, be but still of its initial diameter for at each end.\nUses.\nBlacksmithing.\nSwages are used for shaping the metal in various ways, to enhance its beauty or its fit for a desired purpose.\nElectronics.\nIn printed circuit board assembly individual connector pins are sometimes pressed/swaged into place using an arbor press. Some pins have a hollow end that is pressed over by the arbor's tool to form a mushroom-shaped retaining head. Typical pin diameter range from 0.017 to 0.093 inches (0.43 mm to 2.36 mm) or larger. The swaging is an alternative or supplement to soldering.\nPlastics.\nHeat swaging is a similar process to heat staking, but it involves rolling or reforming a wall (typically a perimeter) of a plastic part to retain another part or component.\nPipes and cables.\nThe most common use of swaging is to attach fittings to pipes or cables (also called wire ropes); the parts loosely fit together, and a mechanical or hydraulic tool compresses and deforms the fitting, creating a permanent joint. Pipe flaring machines are another example. Flared pieces of pipe are sometimes known as \"swage nipples\", \"pipe swages\", or \"reducing nipples\". In furniture, legs made from metal tubing (particularly in commercial furniture) are often swaged to improve strength where they come in contact with the ground, or casters.\nSaw blade teeth.\nIn sawmills, a swage is used to flare large bandsaw or circle saw teeth, which increases the width of the cut, called the kerf. A clamp attaches a mandrel and die to the tooth and the eccentric die is rotated, swaging the tip. A much earlier version of the same operation used a hardened, shaped swage die and a hand held hammer. Saw teeth formed in this way are sometimes referred to as being \"set\". A finishing operation, shaping, cold works the points on the tooth sides to flats. It might be considered as a side swage. This slightly reduces the tooth width but increases the operating time between \"fittings\". Swaging is a major advance over filing as the operation is faster, more precise and greatly extends the working life of a saw.\nManufacturing.\nWhen dealing with rubber components with mold bonded metal sleeves, swaging provides a more controlled and cost-effective alternative to 'shooting' the rubber part into a metal sleeve, where an intensive and less dependable secondary operation is needed to finish the product. A metal can with a bonding component (such as phosphate) is painted to the inside diameter, and molten rubber is injected into the metal sleeve. This creates a product that when cooled may be swaged to the desired size. The second reason for this is that the product is more reliable, and during the swaging process the rubber is more relaxed when the outside can to which the rubber is bonded has its diameter reduced, changing the springrate (K) values and damping coefficient (C) of the rubber. After swaging, any inconsistencies in the metal and rubber have been minimized.\nFirearms.\nIn internal ballistics, swaging describes the process of the bullet entering the barrel and being squeezed to conform to the rifling. Most firearm bullets are made slightly larger than the inside diameter of the rifling, so that they are swaged to engage the rifling and form a tight seal upon firing. Compare to obturate.\nIn ammunition manufacture, swaged bullets are bullets manufactured by compressing metal at room temperature into a die to form it into the shape of a bullet. The other common manufacturing method is casting, which uses molten metals poured into a mold. Since metals expand when heated and contract when cooled, cast bullets must be cast with a mold slightly larger than the desired finish size, so that as the molten metal cools, it will harden at just the right point to shrink to the desired size. In contrast, swaged bullets, since they are formed at the temperature at which they will be used, can be formed in molds of the exact desired size. This means that swaged bullets are generally more precise than cast bullets. The swaging process also leads to fewer imperfections, since voids commonly found in casting would be pressed out in the swaging process. The swaging process in reference to cold flow of metals into bullets is the process not of squeezing the metals into smaller forms but rather pressing smaller thinner items to form into shorter and slightly wider shapes.\nIndividuals who make their own bullets usually are not aware of available manual specialized equipment and dies required for swaging bullets, and thus choose to make cast bullets. To get high precision results, it is common to cast the bullets slightly oversized, then swage the resulting castings through a die to do the final forming. Since the amount of pressure required to size the bullet is far less than that required to form a bullet, a simple mechanical press can be used, often the same press used for handloading ammunition.\nAll of the larger manufacturers of reloading equipment have abandoned making or marketing bullet swaging equipment due to the downturn in the popularity of the manual methods and the subsequent loss of sales. Currently there are only a few die makers who manufacture and market bullet swaging equipment. Four die and equipment makers, CH/4D, RCE, Corbin, and Custom Maker Kaine Dies, manufacture the bulk of bullet swaging equipment in the United States.\nMedicine.\nIn surgery, the thread used in sutures is often swaged to an eyeless needle in order to prevent damage as the needle and suture thread are drawn through the wound.\nMusical instrument repair.\nIn musical instrument repair the usual term on both sides of the Atlantic is swedging, not swaging, though it is generally acknowledged that the former derives from the latter. Keyed instruments such as the clarinet, bassoon, oboe and flute need swedging when years of key movement has worn or compressed the metal of the hinge tube they swivel on and made it slightly shorter, so that the key can travel along the rod it is mounted on instead of being held firmly between the posts attaching the rod to the body of the instrument. This gives rise to floppy keys and a poor air-seal and needs to be corrected by lengthening (swedging) the hinge tube. This is a job that needs to be done by hand, and swedging pliers with highly polished oval holes in the jaws to fit common sizes of hinge tubes are often used to achieve this, though various proprietary designs of swedging tools are available to do the same job more efficiently.\nIn piano technology, swaging happens in several areas: key leads, underlever leads, and bass strings. Key leads which, in the piano's earliest history, were actually made using lead, are soft, round chunks that are inserted into holes drilled into the side of piano keys as a means of balancing actions. Key leads vary in size, generally small, medium, and large. Basically, key leads help to make a keyboard's touch light enough to play. Over time, fluctuations in humidity and aging of wood in piano key-sticks and underlevers causes space to develop around leads, causing them to rattle, tick, or knock. Loose leads in underlevers tend to be the most annoying to pianists because it's difficult to pinpoint where the noise (often a \"tick\" sound) is coming from. The remedy for the noise is swaging—squashing the leads with a short steel rod. Swaging the lead fills the void and eliminates the noise.\nBass strings in pianos are generally constructed with round—sometimes hexagonal—drawn-steel cores, over which copper is wound. Especially on round core wire, the last several inches of the area where the winding terminates is often flattened—swaged—to create a grabbing point for the copper winding material.\nCar styling.\nAs swaging is a technique in which cold metal is formed over a grooved tool or swage, the term was adopted in the field of automotive styling to describe when two panels were brought together, an edge of one panel was swaged so to overlap the other to create the impression of one continuous surface.\nThe term is now often used generically to refer to any similar designs.\nLockbolts.\nA lockbolt is a fastener similar to a bolt in appearance and function. However, instead of using screw threads which connect to a nut using a turning motion, a lockbolt has annular grooves around the shaft of the bolt (pin). After placing the lockbolt in a hole, a threadless collar is forced at high pressures around the annular grooves, deforming the collar and permanently locking it into place around the grooves. Swaging is the generic term for setting a lockbolt and collar assembly. During the installation cycle of a lockbolt, the collar is deformed around the pin with locking grooves using special tooling. The tool engages onto the pintail, which is an extra portion of pin material protruding past the collar that the tool grabs and pulls. This force on the pintail pushes the joint together, and the conically-shaped cavity of the tooling is forced down the collar, which reduces its diameter and progressively swages the collar material into the grooves of the harder pin. As the force required for swaging increases during the process, the installation is finalised when the pintail breaks off. Lockbolts could be viewed as a heavy-duty cousin of structural blind rivets (\"pop rivets\" in some regions), though the way the collar material's plastic deformation is achieved is different. Some tools are capable of \"setting\" both variants, as in both cases traction is applied to a sacrificial pintail.", "Engineering,_Manufacturing": 0.9999928474, "qwen": "Yes"}
{"id": "1388228", "revid": "219723", "url": "https://en.wikipedia.org/wiki?curid=1388228", "title": "Electromagnetic forming", "text": "Electromagnetic forming (EM forming or magneforming) is a type of high-velocity, cold process for electrically conductive metals, most commonly copper and aluminium. The workpiece is reshaped by high-intensity pulsed magnetic fields that induce a current in the workpiece and a corresponding repulsive magnetic field, rapidly repelling portions of the workpiece. The workpiece can be reshaped without any contact from a tool, although in some instances the piece may be pressed against a die or former. The technique is sometimes called \"high-velocity forming\" or \"electromagnetic pulse technology\".\nExplanation.\nA special coil is placed near the metallic workpiece, replacing the pusher in traditional forming. When the system releases its intense magnetic pulse, the coil generates a magnetic field which in turn accelerates the workpiece to hyper speed and onto the die.\nThe magnetic pulse and the extreme deformation speed transforms the metal into a visco-plastic state – increasing formability without affecting the native strength of the material. See the magnetic pulse forming illustration for a visualization.\nA rapidly changing magnetic field induces a circulating electric current within a nearby conductor through electromagnetic induction. The induced current creates a corresponding magnetic field around the conductor (see Pinch (plasma physics)). Because of Lenz's Law, the magnetic fields created within the conductor and work coil strongly repel each other.\nIn practice the metal workpiece to be fabricated is placed in proximity to a heavily constructed coil of wire (called the \"work coil\"). A huge pulse of current is forced through the work coil by rapidly discharging a high-voltage capacitor bank using an ignitron or a spark gap as a switch. This creates a rapidly oscillating, ultrastrong electromagnetic field around the work coil.\nThe high work coil current (typically tens or hundreds of thousands of amperes) creates ultrastrong magnetic forces that easily overcome the yield strength of the metal work piece, causing permanent deformation. The metal forming process occurs extremely quickly (typically tens of microseconds) and, because of the large forces, portions of the workpiece undergo high acceleration reaching velocities of up to 300 m/s.\nApplications.\nThe forming process is most often used to shrink or expand cylindrical tubing, but it can also form sheet metal by repelling the work piece onto a shaped die at a high velocity. High-quality joints can be formed, either by electromagnetic pulse crimping with a mechanical interlock or by electromagnetic pulse welding with a true metallurgical weld. Since the forming operation involves high acceleration and deceleration, mass of the work piece plays a critical role during the forming process. The process works best with good electrical conductors such as copper or aluminum, but it can be adapted to work with poorer conductors such as steel.\nComparison with mechanical forming.\nElectromagnetic forming has a number of advantages and disadvantages compared to conventional mechanical forming techniques.\nSome of the advantages are;\nThe principle disadvantages are;", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "65260100", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=65260100", "title": "Timeline of the COVID-19 pandemic in India (June–December 2020)", "text": "The following is the timeline of the COVID-19 pandemic in India.\nJune.\n1 June.\n204 deaths and 8,171 cases were reported. New cases were reported in the states/UTs as following:\nAssam: 22 cases\nOdisha: 156 cases\nDelhiː 990 cases\nMaharashtraː 2,361 cases\n2 June̝.\n217 deaths and 8,909 cases were reported. New cases were reported in the states/UTs as following:\nAndhra Pradeshː 115 cases\nTamil Naduː 1,091 cases\nKeralaː 86 cases\n3 June̝.\n293 deaths and 9,304 cases were reported. New cases were reported in the states/UTs as following:\nTamil Naduː 1,286 cases\nAndhra Pradeshː 79 cases\nKeralaː 82 cases\nMaharashtraː 2,560 cases\n4 June.\n273 deaths and 9,851 cases were reported. New cases were reported in the states/UTs as following:\nAndhara Pradesh: 98 cases\nMaharashtraː 2,933 cases\nGujaratː 485 cases\nTamil Naduː 1373 cases\n5 June.\n294 deaths and 9,887 cases were reported. New cases were reported in the states/UTs as following:\nAndhra Pradesh: 50 cases\nMaharashtraː 2436 cases\nTamil Nadu: 1,438 cases\nKarnataka: 515 cases\n6 June.\n287 deaths and 9,971 cases were reported. New cases were reported in the states/UTs as following:\nKarnataka: 378 cases\nBihar: 147 cases\nAndhra Pradesh: 161 cases\nMaharashtraː 2,739 cases\nGujaratː 498 cases\n7 June.\n271 deaths and 9,983 cases were reported. New cases were reported in the states/UTs as following:\nAndhra Pradesh: 130 cases\nDelhi: 1,320 cases\n8 June.\n271 deaths and 9,983 cases were reported. New cases were reported in the states/UTs as following: New cases were reported in the states/UTs as following:\nAndhra Pradesh: 125 cases\nOdisha: 138 cases\nKerala: 91 cases\n9 June.\n274 deaths and 9985 cases were reported.\nTamil Nadu: 1,685 cases\nAndhra Pradesh: 147 cases\nKarnataka: 161 cases\n10 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 1927 cases\nKarnataka: 120 cases\nAndhra Pradesh: 218 cases\n11 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 1875 cases\nKarnataka: 204 cases\nAndhra Pradesh: 135 cases\n12 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 1982 cases\nAndhra Pradesh: 141 cases\nOdisha: 112 cases\n14 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 1974 cases.\nKarnataka: 176 cases.\nAndhra Pradesh: 253 cases.\n15 June.\nNew cases were reported in the states/UTs as following:\nKartataka: 213 cases.\nTamil Nadu: 1843 cases.\n16 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 1515 cases.\nKarnataka: 317 cases.\n17 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 2174 cases.\nWest Bengal: 391 cases.\nAndhra Pradesh: 275 cases.\n18 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 2141 cases.\nKarnataka: 210 cases.\nAndhra Pradesh: 210 cases.\n19 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 2115 cases.\nGujarat: 540 cases.\n20 June.\nNew cases were reported in the states/UTs as following:\nKarnataka: 416 cases.\nTamil Nadu: 2396 cases.\n21 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 2352 cases.\nKarnataka:453 cases.\nAndhra Pradesh: 477 cases.\n23 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 2516 cases.\nAndhra ̪Pradesh: 462 cases.\n24 June.\nNew cases were reported in the states/UTs as following:\nMaharastra: 3890 cases.\nTamil Nadu:2865 cases.\n25 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 2509 cases.\nAndhra Pradesh: 553 cases.\n26 June.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 3523 cases.\nMaharashtraː 5024 cases.\n27 June.\nNew cases were reported in the states/UTs as following:\nDelhiː 2948 cases.\nTamil Naduː 3713 cases.\n28 June.\nNew cases were reported in the states/UTs as following:\nDelhiː 2889 cases.\nTamil Naduː 3940 cases.\n29 June.\nNew cases were reported in the states/UTs as following:\nTamil Naduː 3949 cases.\n30 June.\nNew cases were reported in the states/UTs as following:\nTamil Naduː 3943 cases.\nKeralaː 131 cases.\nJuly.\n1 July.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 3882 cases\nUttar Pradesh: 564 cases\n2 July.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 4343 cases.\nPunjab: 120 cases.\n3 July.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 4329 cases.\nKerala: 211 cases.\n4 July.\nNew cases were reported in the states/UTs as following:\nDelhi: 2505 cases.\nTamil Nadu: 4280 cases.\n5 July.\nNew cases were reported in the states/UTs as following:\nDelhi: 2244 cases.\nAndhra Pradesh: 2244 cases.\n6 July.\nNew cases were reported in the states/UTs as following:\nMaharashtra: 5368 cases.\nTamil Nadu: 3827 cases.\n7 July.\nNew cases were reported in the states/UTs as following:\nUttar Pradesh: 1346 cases.\nMaharashtra: 5134 cases.\n8 July.\nNew cases were reported in the states/UTs as following:\nKerala: 301 cases.\nTamil Nadu: 3756 cases.\n9 July.\nNew cases were reported in the states/UTs as following:\nAndhra Pradesh: 155 cases.\nDelhi: 2187 cases.\n10 July.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 3680 cases.\nAndhra Pradesh: 1608 cases.\n11 July.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 3965 cases.\nAndhra Pradesh: 1813 cases.\n12 July.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 4244 cases.\nDelhi: 1574 cases.\n13 July.\nNew cases were reported in the states/UTs as following:\nUttar Pradesh: 1644 cases.\nTamil Nadu: 4328 cases.\n15 July.\nNew cases were reported in the states/UTs as following:\nKerala: 623 cases.\nAndhra Pradesh: 2432 cases.\n16 July.\nNew cases were reported in the states/UTs as following:\nMaharashtra: 8641 cases.\nKarnataka: 4169 cases.\n17 July.\nNew cases were reported in the states/UTs as following:\nMaharashtra: 8308 cases.\nKarnataka: 3693 cases.\n18 July.\nNew cases were reported in the states/UTs as following:\nDelhi: 1475 cases.\nTamil Nadu: 4807 cases.\n19 July.\nNew cases were reported in the states/UTs as following:\nDelhi: 1211 cases.\n20 July.\nNew cases were reported in the states/UTs as following:\nAndhra Pradesh: 4074 cases.\nKerala: 794 cases.\n21 July.\nNew cases were reported in the states/UTs as following:\nDelhi: 1349 cases.\nTamil Nadu: 4965 cases.\n22 July.\nNew cases were reported in the states/UTs as following:\nMaharashtra: 10576 cases.\n23 July.\nNew cases were reported in the states/UTs as following:\nMaharashtra: 9895 cases.\n24 July.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 6785 cases.\n25 July.\nNew cases were reported in the states/UTs as following:\nDelhi: 1142 cases.\nTamil Nadu: 6988 cases.\n26 July.\nNew cases were reported in the states/UTs as following:\nRajasthan: 1120 cases.\n27 July.\nNew cases were reported in the states/UTs as following:\nMaharashtra: 7924 cases.\n28 July.\nNew cases were reported in the states/UTs as following:\nMaharashtra: 7717 cases.\n29 July.\nNew cases were reported in the states/UTs as following:\nTamil Nadu: 6426 cases.\n30 July.\nNew cases were reported in the states/UTs as following:\nAndhra Pradesh: 10167 cases.\n31 July.\nNew cases were reported in the states/UTs as following:\nMaharashtra: 10167 cases.\nAugust.\n1 August.\nKerala: 1129 cases.\nTamil Nadu: 5879 cases.\n2 August.\nMaharashtra: 9509 cases.\n8 August.\nIndian Medical Association says nearly 198 doctors died due to COVID.\nDecember.\nlock down started on 28 December 2022 19,855 cases", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "6553782", "revid": "1162705950", "url": "https://en.wikipedia.org/wiki?curid=6553782", "title": "Finished goods", "text": "Finished goods are goods that have completed the manufacturing process but have not yet been sold or distributed to the end user.\nManufacturing.\nManufacturing has three classes of inventory:\nA good purchased as a \"raw material\" goes into the manufacture of a product. A good only partially completed during the manufacturing process is called \"work in process\". When the good is completed as to manufacturing but not yet sold or distributed to the end-user, it is called a \"finished good\".\nThis is the last stage for the processing of goods. The goods are ready to be consumed or distributed.\nThere is no processing required in term of the goods after this stage by the seller. Though there maybe instance that seller finished goods become buyer’s raw materials\nFinished goods is a relative term. In a Supply chain management flow, the finished goods of a supplier can constitute the raw material of a buyer.", "Engineering,_Manufacturing": 0.9972085953, "qwen": "Yes"}
{"id": "6554792", "revid": "42342156", "url": "https://en.wikipedia.org/wiki?curid=6554792", "title": "Flash (manufacturing)", "text": "Flash, also known as flashing, is excess material attached to a molded, forged, or cast product, which must usually be removed. This is typically caused by leakage of the material between the two surfaces of a mold (beginning along the parting line) or between the base material and the mold in the case of overmolding.\nDetails.\nMolding flash is seen when the optimized parameter on cull height is not calibrated. Proper design of mold parting surfaces can reduce or eliminate flash.\nMolding flash can be caused from old or worn mold cavities that no longer fit tightly together. Other times, the complexity of the part requires so many mating pieces with such precise geometries that it is almost impossible to create a perfect fit on every impression. Most often, the type of material being molded, and its attendant viscosity in its liquid form, is the primary factor that leads to the creation of the unwanted mold flash.\nThe process of removing flash, known as deflashing, is commonly performed via cutting, breaking, grinding, or tumbling. Some foundries use robot autogrinders to remove this unwanted material. It is very typical for molders to have their operators trim flash with hand tools at the molding machine between cycles. Many molders and OEMs seek out the use of batch processes including vibratory tumbling, cryogenic deflashing or media blasting to remove unwanted flash from large batches of parts.\nWitness mark.\nIn plastic injection, a faint mark called a witness mark (or witness line) will occur along the parting line. This is unavoidable and is usually accepted despite the minor aesthetics issue. However, some part surfaces (e.g. when used for sealing) cannot tolerate witness marks, and thus either the marks must be removed post-molding or the mold redesigned.", "Engineering,_Manufacturing": 0.9996831417, "qwen": "Yes"}
{"id": "8124740", "revid": "1161731413", "url": "https://en.wikipedia.org/wiki?curid=8124740", "title": "Harsco", "text": "Harsco Corporation is an environmental solutions company based in Philadelphia, Pennsylvania. Harsco operates in over 30 countries and employs approximately 12,000 people worldwide. The company provides solutions for complex environmental issues and serves large industries, including steel, railways, and energy. Harsco's common stock is a component of the S&P SmallCap 600 Index and the Russell 2000 Index.\nHistory.\nHarsco was founded in 1853 as The Harrisburg Car Manufacturing Company and became the Harrisburg Steel Corporation in 1935. Following a series of acquisitions, the company became Harsco Corporation in 1956, forming three divisions: Metals & Minerals (Now Harsco Environmental), Rail, and Industrial.\nBy the early 1990s, Harsco products and services covered defense, industrial, commercial, and construction applications, with over 250 manufacturing, reclamation, distribution, and service facilities across 14 countries.\nIn 2018, Harsco acquired Altek, a UK producer of aluminum processing equipment. \nIn 2019, Harsco Metals & Minerals rebranded to Harsco Environmental, and acquired Clean Earth, a U.S. provider of environmentally sustainable solutions for specialty waste streams.\nIn April 2020, Harsco Corporation acquired the Environmental Solutions business (ESOL) from Stericycle, Inc.\nHarsco currently operates as the mother company with its two main divisions Clean Earth and Harsco Environmental. Additional subsidiary companies include ALTEK, SteelPhalt, and Black Beauty Abrasives.\nFinancial information.\nHarsco reported total sales of USD $1.89 billion in fiscal year 2022.\nStock exchanges.\nHarsco is traded publicly on NYSE with ticker symbol HSC.", "Engineering,_Manufacturing": 0.9967024326, "qwen": "Yes"}
{"id": "8129124", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=8129124", "title": "Hand mould", "text": "A hand mold is a simple mold used for low quantity work. It is used in the injection molding and printing industries.\nIt is made by a hand injection molding machine. It is a simple machine which contains a barrel, handle, nozzle, mold and heaters.\nPrinting.\nIn the printing industry, a hand mold specifically refers to a two-part mold used for casting hand-made type. Inside the mold is a matrix.\nIn particular, it refers to a system for casting movable type, pioneered by Johannes Gutenberg, which was widely used in the early era of printing in Europe (15th-16th century).\nIn this method, the type was made by punching a letter-shaped cavity in a matrix made of some soft metal (typically copper). Then this matrix would be held in the lower part of the mold, the upper part would close on it, and molten type metal would be poured into the cavity. Using the hand mold, the printer could quickly make any additional type he might need.\nInjection molding.\nIn injection molding, hand molds refer to simple molds that have no provision for heat, cooling, or ejection. This means when a hand mold is cycled universal heating plates are required to warm the molds and the molds must be removed after each cycle to remove the moldings. This drastically increases the cycle time, which limits it to short runs, but to offset this is the low cost of the mold. They are usually single cavity molds, but may be multi-cavity if the molding is quite small. They are usually only of a two or three plate design because of the simplicity of the parts. If only a short run is required then the molds may be made from aluminum or brass, but if more parts are required then they are made from conventional steels.\nBullet casting.\nHand cast bullets remain popular with the handloading, muzzleloading and small custom ammunition loading communities. In a tradition dating back to the beginning of firearms, molds matched to the bore (and the chamber for breech loading weapons) are custom made for each weapon. Anywhere from one to six cavities are carved into the molding block, along with appropriate gates and sprues. As the blocks are now usually made out of aluminum, which does not allow lead alloys to stick, only a small amount of parting compound is needed.", "Engineering,_Manufacturing": 0.9998925924, "qwen": "Yes"}
{"id": "24436541", "revid": "6289403", "url": "https://en.wikipedia.org/wiki?curid=24436541", "title": "Router table (woodworking)", "text": "A router table is a stationary woodworking machine in which a vertically oriented spindle of a woodworking router protrudes from the machine table and can be spun at speeds typically between 3000 and 24,000 rpm. Cutter heads (router bits) may be mounted in the spindle chuck. As the workpiece is fed into the machine, the cutters mold a profile into it. The machine normally features a vertical fence, against which the workpiece is guided to control the horizontal depth of cut. Router tables are used to increase the versatility of a hand-held router, as each method of use is particularly suited to specific application, e.g. very large workpieces would be too large to support on a router table and must be routed with a hand-held machine, very small workpieces would not support a hand-held router and must be routed on a router table with the aid of pushtool accessories etc.\nVarieties.\nRouter tables exist in three varieties:\nUse.\nRouter tables are used in one of three ways. In all cases, an accessory is used to direct the workpiece.\nHistory.\nRouter tables evolved as shop improvised tools. Individual woodworkers began taking routers, mounting them in an inverted position beneath a table, and using the routers' depth adjustment to raise the bit through a hole in the table surface.\nOver time manufacturers began selling accessories (pre-made table tops, table legs, table inserts, fences, hold downs, vertical adjustment tools (\"lifts\"), etc.\nFinally, manufacturers began selling complete packages, such as the Inverted Pin Router, which put them in the business of effectively selling wood shapers, the very tool that shop improvised router tables were created as inexpensive substitutes for.", "Engineering,_Manufacturing": 0.9999980927, "qwen": "Yes"}
{"id": "20644699", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=20644699", "title": "Low plasticity burnishing", "text": "Low plasticity burnishing (LPB) is a method of metal improvement that provides deep, stable surface compressive residual stresses with little cold work for improved damage tolerance and metal fatigue life extension. Improved fretting fatigue and stress corrosion performance has been documented, even at elevated temperatures where the compression from other metal improvement processes relax. The resulting deep layer of compressive residual stress has also been shown to improve high cycle fatigue (HCF) and low cycle fatigue (LCF) performance.\nHistory.\nUnlike LPB, traditional burnishing tools consist of a hard wheel or fixed lubricated ball pressed into the surface of an asymmetrical work piece with sufficient force to deform the surface layers, usually in a lathe. The process does multiple passes over the work pieces, usually under increasing load, to improve surface finish and deliberately cold work the surface. Roller and ball burnishing have been studied in Russia and Japan, and were applied most extensively in the USSR in the 1970s. Various burnishing methods are used, particularly in Eastern Europe, to improve fatigue life. Improvements in HCF, corrosion fatigue and SCC are documented, with fatigue strength enhancement attributed to improved finish, the development of a compressive surface layer, and the increased yield strength of the cold worked surface.\nLPB was developed and patented by Lambda Technologies in Cincinnati, Ohio in 1996. Since then, LPB has been developed to produce compression in a wide array of materials to mitigate surface damage, including fretting, corrosion pitting, stress corrosion cracking (SCC), and foreign object damage (FOD), and is being employed to aid in daily MRO operations. To this day, LPB is the only metal improvement method applied under continuous closed-loop process control and has been successfully applied to turbine engines, piston engines, propellers, aging aircraft structures, landing gear, nuclear waste material containers, biomedical implants, armaments, fitness equipment and welded joints. The applications involved titanium, iron, nickel and steel-based components and showed improved damage tolerance as well as high and low cycle fatigue performance by an order of magnitude.\nHow it works.\nThe basic LPB tool is a ball, wheel or other similar tip that is supported in a spherical hydrostatic bearing. The tool can be held in any CNC machine or by industrial robots, depending on the application. The machine tool coolant is used to pressurize the bearing with a continuous flow of fluid to support the ball. The ball does not contact the mechanical bearing seat, even under load. The ball is loaded at a normal state to the surface of a component with a hydraulic cylinder that is in the body of the tool. LPB can be performed in conjunction with chip forming machining operations in the same CNC machining tool.\nThe ball rolls across the surface of a component in a pattern defined in the CNC code, as in any machining operation. The tool path and normal pressure applied are designed to create a distribution of compressive residual stress. The form of the distribution is designed to counter applied stresses and optimize fatigue and stress corrosion performance. Since there is no shear being applied to the ball, it is free to roll in any direction. As the ball rolls over the component, the pressure from the ball causes plastic deformation to occur in the surface of the material under the ball. Since the bulk of the material constrains the deformed area, the deformed zone is left in compression after the ball passes.\nBenefits.\nThe LPB process includes a unique and patented way of analyzing, designing, and testing metallic components in order to develop the unique metal treatment necessary to improve performance and reduce metal fatigue, SCC, and corrosion fatigue failures. Lambda modifies the process and tooling for each component to provide the best results possible and to ensure that the apparatus reaches every inch on the component. With this practice of customization along with the closed-loop process control system, LPB has been shown to produce a maximum compression of 12mm, although the average is around 1-7+mm. LPB has even been shown to have the ability to produce through-thickness compression in blades and vanes, greatly increasing their damage tolerance over 10-fold, effectively mitigating most FOD and reducing inspection requirements. No material is removed during this process, even when correcting corrosion damage. LPB smooths surface asperities during machining, leaving an improved, almost mirror-like surface finish that is vastly better looking and better protected than even a newly manufactured component.\nCold working.\nThe cold work produced from this process is typically minimal, similar to the cold work produced by laser peening, only a few percent, but a great deal less than shot peening, gravity peening or, deep rolling. Cold work is particularly important because the higher the cold work at the surface of a component, the more vulnerable to elevated temperatures and mechanical overload that component will be and the easier the beneficial surface residual compression will relax, rendering the treatment pointless. In other words, a component that has been highly cold worked will not hold the compression if it comes into contact with extreme heat, like an engine, and will be just as vulnerable as it was to start. Therefore, LPB and laser peening stand out in the surface enhancement industry because they are both thermally stable at high temperatures. The reason LPB produces such low percentages of cold work is because of the aforementioned closed-loop process control. Conventional shot peening processes have some guesswork involved and are not exact at all, causing the procedure to have to be performed multiple times on one component. For example, shot peening, in order to make sure every spot on the component is treated, typically specifies coverage of between 200% (2T) and 400% (4T). This means that at 200% coverage (2T), 5 or more impacts occur at 84% of locations and at 400% coverage (4T), it is significantly more. The problem is that one area will be hit several times while the area next to it is hit fewer times, leaving uneven compression at the surface. This uneven compression results in the whole process being easily \"undone\", as was mentioned above. LPB requires only one pass with the tool and leaves a deep, even, beneficial compressive stress.\nThe LPB process can be performed on-site in the shop or in situ on aircraft using robots, making it easy to incorporate into everyday maintenance and manufacturing procedures. The method is applied under continuous closed loop process control (CLPC), creating accuracy within 0.1% and alerting the operator and QA immediately if the processing bounds are exceeded. The limitation of this process is that different CNC processing codes need to be developed for each application, just like any other machining task. The other issue is that because of dimensional restrictions, it may not be possible to create the tools necessary to work on certain geometries, although that has yet to be a problem.", "Engineering,_Manufacturing": 1.0000038147, "qwen": "Yes"}
{"id": "28523560", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=28523560", "title": "Product concept", "text": "A product concept is a description of a product or service, at an early stage in the product lifecycle. It is generated before any detailed design work is undertaken and takes into consideration market analysis, customer experience, product features, product cost, strategic fit, and product architecture.\nA product concept should describe how the new product will appeal to its target market. While the product concept is based upon the idea that customers prefer products that have the most quality, performance, and features, some customers prefer a product that is simpler and easier to use.", "Engineering,_Manufacturing": 0.9999263287, "qwen": "Yes"}
{"id": "57203691", "revid": "16501562", "url": "https://en.wikipedia.org/wiki?curid=57203691", "title": "Green strength", "text": "Green strength, or handling strength, can be defined as the strength of a material as it is processed to form its final ultimate tensile strength. This strength is usually considerably lower than the final ultimate strength of a material. The term green strength is usually referenced when discussing non-metallic materials such as adhesives and elastomers (such as rubber). Recently, it has also been referenced in metallurgy applications such as powdered metallurgy.\nAdhesives.\nA joint made through the use of an adhesive can be referred to as an adhesive joint or bond.\nThe green strength of adhesives is the early development of bond strength of an adhesive. It indicated \"that the adhesive bond is strong enough to be handled a short time after the adherents are mated but much before full cure is obtained.\" Usually, this strength is significantly lower than the final curing strength. Most adhesives typically have an initial green strength and a final ultimate tensile strength listed for their application. For household adhesives, this data is usually reflected on the packaging.\nThe best example of this is seen in typical epoxies from a local hardware stores. During curing, the epoxy will travel into an initial curing phase, also called \"green phase\", when it begins to gel. At that point, the epoxy is no longer workable and will move from being tacky to a firm rubber-like texture. While the epoxy is only partially cured at this point, it has formed a lower green strength. Normally, this process occurs within 30 minutes to 1 hour. At this time, the part in question can be handled, but cannot handle large loads or stress. It typically takes up to 24 hours for a standard epoxy to cure to its final and complete strength.\nTemperature is an important factor in the time it takes for an adhesive to form the green strength. While this can vary from adhesive to adhesive, general speaking, heat can speed up the process to form the green strength and the overall curing time. Time-Temperature-Transformation Diagrams exist for various adhesives that relate the time and temperature to the state of the adhesive during curing. This allows for a proper understanding of when the green strength will be reached for an adhesive joint based on certain conditions.\nTesting.\nMechanical testing can be used to verify the green strength of a material. This will allow the user the understand the amount of load that can be applied in the green phase before final cure.\nTensile loading can be verified by various testing methods. Multiple ASTM specifications exist for the tensile testing of adhesives that are relatively easy to follow. Such tests include the process of attaching the adhesive to two adherents (typically wood or steel) then testing the joint with a pull-type test. One example is the use us ASTM Test Method D2095. In this test, two metal rod ends are polished so it contains no burrs that could affect the adhesive bond. It also machined so the surfaces are perfectly parallel. The rods are then butted against each with the adhesive joining them. As it cures and sets, the fulfillment of green strength can be tested by a pull test, putting the bond in full tension load.\nShear loading can also be tested in respect to green strength. Most adhesive bonds used in design require the bond to typically be in a state of shear, not tensile. Because of this, it is very important to understand the shear loading of a joint in relation to its green strength and final strength. Just like in tensile loading, ASTM provides very specific testing methods for a joint in shear loading.\nThe standard lap shear specimen test is described in ASTM D1002. This test is the single common and discussed test method for adhesive bonds. In this method, the surface is prepped and cleaned for each specimen. The adhesive is then applied to the area that will be lapped. This lap length is generally 0.5\" and the bond width is 1\". The bond is then fixed and allowed to cure. For green strength testing, the fixture can be removed, at the appropriate time, and the specimen can be loaded in shear until it finally fails. This will verify the green strength of the material.\nOther testing, such as cleavage loading and peel test, can be used to determine both the green strength and final strength of a material. These are typically not reflected on the data sheet for standard adhesives, but can be used for testing of adhesives based on their applications in residential and commercial environments.\nElastomers.\nIn the elastomer industry, \"green strength\" describes the strength of an elastomer in an unvulcanized, uncured state. The most popular referenced type of elastomer is rubber.\nFor rubber composites, green strength is essential during formation and manufacturing of materials such as radial tires, tank tracks, etc. These rubbers must be stretched from one mill to another during processing to form the final, vulcanized product. Green strength allows these transfers without tearing or wrinkling the workpiece.\nTo improve the green strength of elastomers and prevent issues during forming, various additives and compounds are typically added to the composite. Also, fabrication and forming techniques have been modified to reduce the amount of stress on the material before it is vulcanized. These techniques are a pertinent component of the tire making industry because it is a process that requires much forming, stretching, and bending during fabrication before the final curing is complete.\nMetals.\nGreen strength of metals is typically referenced in the field of powder metallurgy.\nPowder metallurgy refers to the fabrication of materials or components from powders. In powder metallurgy, the initial green strength is formed during compacting and forming. Increased complexity of parts and geometry have created a need for a higher green strength during this process.\nThere are several limitations that restrict the ability to increase green strength in powder metallurgy components. Characteristics such as particle size and compressibility pose limits on the final green strength.\nVarious studies have been undertaken to improve the green strength of powder metallurgy. The use of advanced lubricants and the addition of high alloys have shown that it is possible to increase the green strength of these materials.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "57216564", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=57216564", "title": "Welding of advanced thermoplastic composites", "text": "Advanced thermoplastic composites (ACM) have a high strength fibres held together by a thermoplastic matrix. Advanced thermoplastic composites are becoming more widely used in the aerospace, marine, automotive and energy industry. This is due to the decreasing cost and superior strength to weight ratios, over metallic parts. Advance thermoplastic composite have excellent damage tolerance, corrosion resistant, high fracture toughness, high impact resistance, good fatigue resistance, low storage cost, and infinite shelf life. Thermoplastic composites also have the ability to be formed and reformed, repaired and fusion welded.\nFusion bonding fundamentals.\nFusion bonding is a category of techniques for welding thermoplastic composites. It requires the melting of the joint interface, which decreases the viscosity of the polymer and allows for intermolecular diffusion. These polymer chains then diffuse across the joint interface and become entangled, giving the joint its strength.\nWelding techniques.\nThere are many welding techniques that can be used to fusion bond thermoplastic composites. These different techniques can be broken down into three classifications for their ways of generating heat; frictional heating, external heating and electromagnetic heating. Some of these techniques can be very limited and only used for specific joints and geometries.\nFriction welding.\nFriction welding is best used for parts that are small and flat. The welding equipment is often expensive, but produces high-quality welds.\nLinear vibration welding.\nTwo flat parts are brought together under pressure with one fixed in place and the other vibrating back-and-forth parallel to the joint. Frictional heat is then generated till the polymers are softened or melted. Once the desired temperature is met, the vibration motion stops, the polymer solidifies and a weld joint is made. The two most important welding parameters that affect the mechanical performance are welding pressure and time. Developing parameters for different advance thermoplastic composite can be challenging because the high elastic modulus of the material will have a higher heat generation, requiring less weld time. The pressure can affect the fiber orientation which also greatly impact the mechanical performance. Lap shear joints tend to have the best mechanical performance from the higher volume fraction of fibers at the weld interface. Overall linear vibration welding can achieve high production rates with excellent strength, but is limited to the joint geometries that are flat.\nSpin welding.\nSpin welding is not a very common welding technique for advanced thermoplastic composites because this can only be done with parts that have a circular geometry. This is done by one part remaining stationary while the other is continuously rotated with pressure applied to the weld interface. Rotational velocity will vary throughout different radii of the Interface. This will result in a temperature gradient as a function of the radius, resulting in different shrinkage for the fibers causing high residual stresses. The orientation of the fibers will also contribute to high residual stress and reduction in strength.\nUltrasonic welding.\nUltrasonics welding is one of the most commonly used technique for welding advanced thermoplastic composites. This is due for its ability to maintain high weld strength, hermetic sealing, and high production rates. This welding technique operates at high vibrational frequencies (10–70 kHz) and low amplitude. The direction of vibration is perpendicular to the joint surface, but can also be parallel to the joint for hermetic application. Heat is generated from the surface and intermolecular friction due to the vibrational. On the surface of the joint there are small asperities called energy directors, where the vibrational energy concentrates and induces melting. Design of the energy director and optimized parameters can be critical to improve the quality of the weld to reducing any fiber disruption during welding. Energy directors that are triangular or semi-circle often achieve the highest strength. With optimize welding parameters and joint design weld strength, up to 80% of the base material can be retained for advanced thermoplastic composites. However, welding can cause damage to the fibers, which will result in premature failure. Ultrasonic welding of advanced thermoplastic composites is used for making automotive parts, medical devices and battery housing.\nThermal welding.\nThermal welding can produce good weld quality although extra precautions need to be taken to prevent high residual stress, warping, and decohesion. Other thermal welding techniques are not commonly used due their high heat input, which can damage the composite.\nLaser welding.\nLaser welding of advanced thermoplastic composites is a process by which the LASER (Light Amplification of Simulated Emission of electromagnetic Radiation), a highly focused coherent beam of light melts the composite tin various ways. Taking advantage of joint design and material properties, lasers can be applied either directly or indirectly to create the welded joint. There are processing methods that take advantage of material structure/properties to create the weld joint. Welding variables affect weld quality in both positive and negative ways depending on how they are manipulated.\nLaser heating mechanism in matter.\nWhen a laser beam impinges on a material, it excites electrons in the outer most shell of the atom. The return of those electrons to the relaxed state induces thermal heating through conversion to vibrational states which propagate to the surrounding material.\nJoining methods for laser welding.\nSurface heating.\nThis method involves using infrared radiation to heat the surfaces the composites to be welded and then clamping until and holding the parts together.\nIR/Laser stacking.\nThis method involves laser melting a polymer post and pressing a die into the molten post to create a rivet-like button to joint materials like metals. This process can be used to join metallic joints to composite structures.\nThrough Transmission IR welding (TTIr).\nThis method utilizes one laser transparent (LT) and one laser absorbing (LA) material. Typically, the components are layered as a sandwich with the laser beam passing through the LT layer and irradiating the surface of the LA. This creates a melt layer at the interface of two components leading to a weld.\nEffect of Constituent Properties on Weldability.\nTo understand how the properties of a composite affect is weldability, the effects of the individual constituents (fiber, matrix, additives, etc.) need to be understood. The effect of each will be noted separately and then the combined effects will be discussed.\nMatrix.\nElectromagnetic radiation interaction.\nA laser beam can interact in one of three ways when it contacts the polymer matrix. It can be absorbed, transmitted, or reflected. The amount of absorption determines the amount of energy available for welding. The reflectivity is affected by the index of refraction according to this relation: formula_1, where n is the index of refraction of the polymer and m is the index of refraction of air.\nAbsorption can be affected by the following structural characteristics of the polymer to be discussed below: crystallinity, chemical bonding, and concentration of additives.\nCrystallinity.\nIncreased crystallinity tends to cause lower laser beam transmission because of scattering caused by changes in the index of refraction encountered when going from one phase to the next or because of changing crystallographic orientation. Increased crystallinity can cause the transmission to increase monotonically as a function of polymer thickness. The relationship follows the Lambert-Bouuger's Law: formula_2, where formula_3 is the intensity of the laser beam at a given depth or thickness, t. formula_4 is the intensity of laser beam at its source. formula_5 is the absorption constant of the polymer. By the same token, amorphous polymers lack this trend with thickness.\nChemical bonding.\nPolymers absorb EMR (Electro Magnetic Radiation) in a specific wavelength of light depending on what functional groups are present on the polymer. For instance, bending of the C-H bond on the formula_6 at 6800 nm. Many polymers have vibrational modes at wavelengths greater than 1100 nm, so to apply methods such as TTIr, laser sources must produce photons at wavelengths shorter than that. Therefore, lasers (1064 nm) and diode lasers (800-950 nm) can pass through the LT until they impinge on the intended modified polymer or additive that results in absorption, whereas CO_2 lasers (10,640 nm) will be absorbed too easily as it passes through the LT.\nReinforcements.\nReinforcements such as fibers or short particles. Reinforcing fibers can be added to increase the strength of a composite.\nSome reinforcements like carbon fibers have high thermal conductivity and can dissipate the heat of welding, thus requiring more energy input than with other reinforcement materials such as glass. Glass reinforcements can cause scattering of the beam.\nThe orientation of the continuous fibers can affect the width of welds being made. When the welding direction is parallel to the orientation of the fibers, the weld width is usually narrower due to heat being channeled through the fibers to the front and the rear of the weld.\nIncreased volume fraction of reinforcements such as glass can scatter the laser beam, thus allowing less to be transmitted to the weld joint. When this happens, the amount of energy necessary to fuse the joint may increase. The increase if not done carefully can cause damage to the transparent part of a TTIr weld joint.\nAdditives and Fillers.\nSome additives can be intentionally added to absorb laser energy. This technique is especially useful in concentrating the weld joint to the mated surfaces of two materials that are relatively transparent to the laser beam. For example, carbon black increases absorption of the laser beam. There can be some unintended consequences of using these absorbing additives. Increasing the concentration of carbon black in a polymer can decrease the depth of heating and increase the peak temperature at the weld joint. Surface damage can occur if the concentration of carbon black becomes excessive.\nSome additives such as the highly selective materials used in the Clearweld process are applied only to the mating surfaces between the plastics to be joined. Some of the chemicals such as cyanines only absorb in a narrow wavelength band centered around 785 nm. This methodology initially was applied only to plastics, but has recently been applied to composites such as carbon fiber reinforced PEEK.\nOther additives called clarifiers can do the opposite of carbon black by increasing laser beam transmission by reducing crystallinity in polymers.\nDespite the fact that both pigments and dyes can both add color to a polymer, they behave differently. A dye is soluble in a polymer, whereas a pigment is not.\nWelding technique comparisons.\nContour Welding (CW) vs quasi-simultaneous (QS).\nDuring TTIr, although it takes more energy per unit length to achieve fusion with QS than with CW, QS offers the advantage of achieving higher weld strength and weldability of low transmissive materials such as continuous glass fiber thermoplastics. Greater strength is imparted because full fusion is achieved without damaging the surface of the transparent material.\nElectromagnetic welding.\nElectromagnetic welding is capable of welding complex parts with also the possibility of reopening welds for replacement or repair. To achieve good welds the design of the coil and implant is important for uniform heating.\nImplant resistance welding.\nImplant resistance welding can be a low cost solution for welding parts that are flat or with curved surfaces. The heating element used is often a metal mesh or carbon strips, which provides uniform heating. However, advanced thermoplastic composites that contain conductive fibers can’t be used due to unwanted power leakages.\nImplant induction welding.\nInduction welding uses a implant or susceptor that is placed at the weld interface and embedded with conductive material such as metal or carbon fibers. An induction coil is then place near the weld joint, which induces a current in embedded in the material used to generate heat. When welding carbon fiber, carbon and graphite fiber mats with higher electrical resistance are used to concentrate the heat at the weld interface. This has the ability to weld complex geometry structures with great weld strength.\nChallenges of welding advanced thermoplastic composites.\nThe heat generated during welding thermoplastic composite, induces residual stresses in the joint. These stresses can greatly reduce the strength and performance of the part. Upon cooling from welding the matrix and fibers will have different coefficients of thermal expansion, which introduces the residual stress. Things such as heat input, cooling rates, volume fraction of the fibers, and matrix material will influence the residual stress. Another important factor to consider is the orientation of the fibers. During the molten state of welding, fibers can reorient themselves in a manner that reduces weld strength.", "Engineering,_Manufacturing": 1.0000023842, "qwen": "Yes"}
{"id": "5122435", "revid": "236191", "url": "https://en.wikipedia.org/wiki?curid=5122435", "title": "Flexibility (engineering)", "text": "Flexibility is used as an attribute of various types of systems. In the field of engineering systems design, it refers to designs that can adapt when external changes occur. Flexibility has been defined differently in many fields of engineering, architecture, biology, economics, etc. In the context of engineering design one can define flexibility as the ability of a system to respond to potential internal or external changes affecting its value delivery, in a timely and cost-effective manner. Thus, flexibility for an engineering system is the ease with which the system can respond to uncertainty in a manner to sustain or increase its value delivery. Uncertainty is a key element in the definition of flexibility. Uncertainty can create both risks and opportunities in a system, and it is with the existence of uncertainty that flexibility becomes valuable.\nFlexible Manufacturing System.\nFlexibility has been especially thoroughly studied for manufacturing systems. For manufacturing science eleven different classes of flexibility have been identified [Browne, 1984], [Sethi and Sethi, 1990]:\nThese definitions yield under current conditions of the system and that no major setups are conducted or investments are made (except \"expansion flexibility\"). Many of the flexibility types are linked to each other; increasing one flexibility type also increases another. But in some cases tradeoffs between two flexibility types are needed.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "18623713", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=18623713", "title": "Zhuhai Zhongfu", "text": "Zhuhai Zhongfu(珠海中富) Enterprise Co., Ltd. engages in the production and supply of PET bottles in China. It offers PET bottles for soft drinks, mineral water, distilled water, tea, and beer. The company's products also include bottle labels, film, and packing paper boxes. Zhuhai Zhongfu Enterprise Co., Ltd. is based in Zhuhai city, Guangdong province, China.\nZhuhai Zhongfu Enterprises Co. has been listed on the Shenzhen market since 1996.\nOwnership.\nCVC Capital Partners acquired a 29% stake in the company in 2007, paying $US225 million. This made CVC the largest single shareholder in the company.\nOperations.\nThe company has operations throughout China and produces approximately 12 billion PET bottles a year.", "Engineering,_Manufacturing": 0.9999667406, "qwen": "Yes"}
{"id": "50938445", "revid": "7852030", "url": "https://en.wikipedia.org/wiki?curid=50938445", "title": "Edwards Manufacturing Company", "text": "Edwards Manufacturing Company is a business in Albert Lea, Minnesota that manufactures Hydraulic Ironworkers.\nHistory.\nManufacturing since 1875 Edwards began with road graders, and other manufacturing equipment such as the stump puller, Manual Shears, and Intake Grates.\nIronworkers.\nEdwards Manufacturing Company manufactures Ironworkers and hydraulic equipment. Ironworkers are machines that speed up fabrication by punching and shearing opposed to drilling or using a saw. Edwards Ironworkers can have a Hydraulic Accessory Pack that allows separate machinery to plug into the Ironworker and use the Ironworker's hydraulic power. Edwards Manufacturing Company has a line of 12 ironworkers and 5 Hydraulic Accessories as of 2015.", "Engineering,_Manufacturing": 0.9999839067, "qwen": "Yes"}
{"id": "67865002", "revid": "40069008", "url": "https://en.wikipedia.org/wiki?curid=67865002", "title": "Chollima-321", "text": "The Chollima-321 (Korean: 천리마 -321) is a North Korean trolleybus with battery power built by the Pyongyang Trolley Bus Factory. The name 'Chollima' refers to a myth about a winged horse that has since been adopted as the name of North Korea's Stakhanovite movement. The production of the Chollima-321 production replaced the Chollima-091 articulated trolleybus, due to the need to replace older Chollima-961, -951, Ikarus and Karosa bus based trolleybuses. The trolleybus features on a 50 won stamp.\nIn Japanese sources, it is called the Mallima-312.\nDesign.\nThe new trolleybus was first tested at night, with Kim Jong-un onboard, which had become a tradition for the testing of new modes of public transport. Before that, Kim Jong-un had visited the trolleybus factory, confirming the specifications of the trolleybus, such as the door width. The vehicle that he had ridden on would be numbered 483, in honour of the route he had taken, and the date on which he had tested it, August 3. The production vehicles differ that there is an additional blinker above the headlights, different lights on the rear and a ladder to the roof at the rear. The first seat is reserved for 'heroes'.\nThe trolleybus has a digital dashboard that monitors the overhead wire voltage, speed and battery voltage. It features a TV manufactured by Potonggang Electronics Factory. Like the Chollima-316, it has LED indicators for the route on front and rear, but the Chollima-321 also has one inside. The vehicle has no air conditioner. A new type of motor, which is more efficient than previous models was introduced on this trolleybus.\nThis model demonstrated that the trolleybus factory had mastered the use of plastic moulding, which was reported as achieved through CNC machines and plasma cutters. It is claimed that almost all parts are built at the factory, which after its refurbishment completed in early 2018, featured a full assembly line for trolleybuses, from framing to painting of the vehicle, with the plating of trolleybuses being automated. A new production process of curved glass was reportedly created for the use in electric public transport. Other production processes that were upgraded for its production included induction furnaces and heating furnaces, used for forging of parts. \nUp until January 2020, it was reported 'more than 100' trolleybuses have been manufactured in recent years, and that despite shortages in 2019, the production was pushed ahead. \nThe design of the Chollima-321 has been displayed at the national industrial design exhibition in celebration of the 75th year anniversary of the founding of the Workers' Party of Korea. Its design has inspired other factories, such as the Chongjin Bus Factory, which serially produced 20 new trolleybuses in a design clearly inspired by the Chollima-321. Other similar models have been built in Hamhung and Pyongsong. The design and colour scheme of the trolleybus is similar to the 'Thongil' tram that was manufactured at the same time.\nService.\nThere are currently 42 known Chollima-321 trolleybuses known to be in operation. Other vehicles, such as the trolleybuses in Chongjin are a completely different model, named 'Jipsan'. ", "Engineering,_Manufacturing": 0.9966592193, "qwen": "Yes"}
{"id": "27418012", "revid": "35393771", "url": "https://en.wikipedia.org/wiki?curid=27418012", "title": "Spread tow fabric", "text": "Spread tow fabric (stf) is a type of lightweight fabric. Its production involves the steps of spreading a tow in thin and flat uni-directional tape (Spread Tow Tape, STT), and weaving the tapes to a Spread Tow Fabric. This technique increases the mechanical properties of the material and is also used to reduce weight on composites. Manufacturers of Spread Tow Tapes include Oxeon AB, Teknomax Corp., Harmoni Industry Inc., Sakaiovex. \nTechnique.\nThe spread tow technique, to weave with tapes instead of tows, tape weaving technology, was invented by Dr. Nandan Khokar in 1995. The theory behind Spread Tow Fabric is quite simple, by arranging the fibres in the woven structure in the straightest orientation possible the fibre properties are used in the most effective way to carry load, both in tensile and compression.\nSTF offers high versatility as it overcomes the limitations of traditional woven fabrics produced using tows. The flatness of STF, which comes from near absence of crimp, significantly reduces accumulation of matrix at the interlacing points and thereby the dead weight of the final composite material. This not only reduces the weight of the final composite material product but also eliminates the print-through defects associated with post curing of the undesired matrix accumulation.\nAlthough the technique is based on the same principles, the spreading of the tow can be made in different way, for example using water or air.\nUses.\nSpread Tow Fabric offers the advantages of relatively lower crimp, increased smoothness and less-pronounced crossover defects. As a greater number of filaments are exposed in STF they also present correspondingly improved wetting ability.\nAdditionally, the STF offers improved mechanical performance, thinness, draping ability and even different aesthetics compared with those produced using 1k – 6k tows.\nSpread Tow Fabric is often produced with carbon fiber and is widely used in the composites industry in a number of applications.\nSpread tow reinforcements (str) are reinforcements made using spread tow material, fabric or UD tapes, which is new category of composite reinforcements.", "Engineering,_Manufacturing": 1.0000072718, "qwen": "Yes"}
{"id": "17733298", "revid": "1120289030", "url": "https://en.wikipedia.org/wiki?curid=17733298", "title": "Photochemical machining", "text": "Photochemical machining (PCM), also known as photochemical milling or photo etching, is a chemical milling process used to fabricate sheet metal components using a photoresist and etchants to corrosively machine away selected areas. This process emerged in the 1960s as an offshoot of the printed circuit board industry. Photo etching can produce highly complex parts with very fine detail accurately and economically.\nThis process can offer economical alternatives to stamping, punching, laser or water jet cutting, or wire electrical discharge machining (EDM) for thin gauge precision parts. The tooling is inexpensive and quickly produced. This makes the process useful for prototyping and allows for easy changes in mass production. It maintains dimensional tolerances and does not create burrs or sharp edges. It can make a part in hours after receiving the drawing.\nPCM can be used on virtually any commercially available metal or alloy, of any hardness. It is limited to materials with a thickness of . Metals include aluminium, brass, copper, inconel, manganese, nickel, silver, steel, stainless steel, zinc and titanium.\nPhotochemical machining is a form of photo engraving, and a similar process in microfabrication is called photolithography.\nProcess.\nThe process starts by printing the shape of the part onto optically clear and dimensionally stable photographic film. The \"phototool\" consists of two sheets of this film showing negative images of the parts (meaning that the area that will become the parts is clear and all of the areas to be etched are black). The two sheets are optically and mechanically registered to form the top and bottom halves of the tool.\nThe metal sheets are cut to size, cleaned and then laminated on both sides with a UV-sensitive photoresist. The coated metal is placed between the two sheets of the phototool and a vacuum is drawn to ensure intimate contact between the phototool and the metal plate. The plate is then exposed in UV light that allows the areas of resist that are in the clear sections of the film to be hardened. After exposure, the plate is \"developed\", washing away the unexposed resist and leaving the areas to be etched unprotected.\nThe etching line is a multi-chambered machine that has driven-wheel conveyors to move the plates and arrays of spray nozzles above and below the plates. The etchant is typically an aqueous solution of acid, frequently ferric chloride, that is heated and directed under pressure to both sides of the plate. The etchant reacts with the unprotected metal essentially corroding it away fairly quickly. After neutralizing and rinsing, the remaining resist is removed and the sheet of parts is cleaned and dried.\nApplications.\nThin gauge (under ) parts in a broad range of alloys are candidates for photo etching.\nIndustrial applications include fine screens and meshes, apertures and masks, battery grids, fuel cell components, sensors, springs, pressure membranes, heat sinks, flexible heating elements, RF and microwave circuits and components, semiconductor leadframes, motor and transformer laminations, metal gaskets and seals, shields and retainers, electrical contacts, encoders and light choppers, EMI/RFI shields, jewelry and washers.\nEconomics.\nPhototooling is quick and inexpensive to produce. Most phototools costs less than $350 and can be produced in two days or less. Unlike \"hard\" tools, such as stamping and punching dies, phototools are exposed only to light and therefore do not suffer wear. Due to the cost of hard tooling for stamping and fine blanking, significant volume is required to justify the expense. Some parts, such as semiconductor leadframes, are so complex and fragile that, despite volumes in the millions of pieces, they can only be produced by photo etching.\nIn PCM, the unit of labor is the sheet. Therefore, it is most economical to plan the largest sheet size possible consistent with the size and dimensional tolerances of the part. The more parts per sheet the lower the unit labor cost per part.\nMaterial thickness affects costs as a function of the length of time to etch through. Most alloys etch at rates between of depth per minute per side.\nIn general, steel, copper or aluminium workpieces with a thicknesses up to , part costs will approximate $0.15–0.20 per square inch. As the geometry of the part becomes more complex, photochemical machining gains greater economic advantage over sequential processes such as CNC punching, laser or water-jet cutting, and electrical discharge machining.", "Engineering,_Manufacturing": 1.0000085831, "qwen": "Yes"}
{"id": "29821539", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=29821539", "title": "Cladding (metalworking)", "text": "Cladding is the bonding together of dissimilar metals. It is different from fusion welding or gluing as a method to fasten the metals together. Cladding is often achieved by extruding two metals through a die as well as pressing or rolling sheets together under high pressure.\nThe United States Mint uses cladding to manufacture coins from different metals. This allows a cheaper metal to be used as a filler. For example, dimes and quarters struck since 1965 have cores made from pure copper, with a clad layer consisting of 75% copper and 25% nickel added during production. Half dollars struck from 1965 to 1969 for circulation and in 1970 for collectors also incorporated cladding, albeit in the case of those coins, the core was a mixture of 20.9% silver and 79.1% copper, and its clad layer was 80% silver and 20% copper. Half dollars struck since 1971 are produced identically to the dimes and quarters.\nLaser cladding is an additive manufacturing approach for metal coatings or precise piece restorations by using high power multi-mode optical fiber laser.\nRoll bonding.\nIn roll bonding, two or more layers of different metals are thoroughly cleaned and passed through a pair of rollers under sufficient pressure to bond the layers. The pressure is high enough to deform the metals and reduce the combined thickness of the clad material. Heat may be applied, especially when metals are not ductile enough. As an example of application, bonding of the sheets can be controlled by painting a pattern on one sheet; only the bare metal surfaces bond, and the un-bonded portion can be inflated if the sheet is heated and the coating vaporizes. This is used to make heat exchangers for refrigeration equipment.\nExplosive welding.\nIn explosive welding, the pressure to bond the two layers is provided by detonation of a sheet of chemical explosive. No heat-affected zone is produced in the bond between metals. The explosion propagates across the sheet, which tends to expel impurities and oxides from between the sheets. Pieces up to 4 x 16 metres can be manufactured. The process is useful for cladding metal sheets with a corrosion-resistant layer.\nLaser cladding.\n\"Laser cladding\" is a method of depositing material by which a powdered or wire feedstock material is melted and consolidated by use of a laser in order to coat part of a substrate or fabricate a near-net shape part (additive manufacturing technology) .\nIt is often used to improve mechanical properties or increase corrosion resistance, repair worn out parts, and fabricate metal matrix composites. Surface material may be laser cladded directly onto a highly stressed component, i.e. to make a self-lubricating surface. However, such a modification requires further industrialization of the cladding process to adapt it for efficient mass production. Further research on the detailed effects from surface topography, material composition of the laser cladded material and the composition of the additive package in the lubricants on the tribological properties and performance are preferably studied with tribometric testing.\nProcess.\nA laser is used to melt metallic powder dropped on a substrate to be coated. The melted metal forms a pool on the substrate; moving the substrate allows the melt pool to solidify in a track of solid metal. Some processes involve moving the laser and powder nozzle assembly over a stationary substrate to produce solidified tracks. The motion of the substrate is guided by a CAM system which interpolates solid objects into a set of tracks, thus producing the desired part at the end of the trajectory.\nAutomatic laser cladding machines are the subject of ongoing research and development. Many of the process parameters must be manually set, such as laser power, laser focal point, substrate velocity, powder injection rate, etc., and thus require the attention of a specialized technician to ensure proper results. By use of sensors to monitor the deposited track height and width, metallurgical properties , and temperature, constant observation from a technician is no longer required to produce a final product. Further research has been directed to forward processing where system parameters are developed around specific metallurgical properties for user defined applications (such as microstructure, internal stresses, dilution zone gradients, and clad contact angle).", "Engineering,_Manufacturing": 0.999976635, "qwen": "Yes"}
{"id": "4399093", "revid": "44329014", "url": "https://en.wikipedia.org/wiki?curid=4399093", "title": "Apple Monitor II", "text": "The Apple Monitor II is a CRT-based green monochrome 12-inch monitor manufactured by Sanyo for Apple Computer; for the Apple II personal computer family. Apple did not introduce the monitor until halfway through the lifespan of the II series. The business-oriented Apple III had its own Apple Monitor III long before. Many home users of Apple II computers used their televisions as computer monitors before the Monitor II was released. It featured an inner vertical-swiveling frame. This allowed users to adjust the viewing angle up or down to suit their taste without the addition of a tilt-and-swivel device. The Monitor II was widely adjustable for the time, including adjustments for the size and location of the image on the screen. These adjustments had a very small influence on the picture, however, much to the dislike of some users. The Monitor II was designed for the Apple II+, but was used widely throughout the Apple II product line, most recognizably on the Apple IIe.", "Engineering,_Manufacturing": 1.0000078678, "qwen": "Yes"}
{"id": "14240940", "revid": "21948199", "url": "https://en.wikipedia.org/wiki?curid=14240940", "title": "DYE Precision", "text": "DYE Precision, also known as simply DYE, is a paintball equipment manufacturing company and a well known Numerical control (CNC) manufacturing company operated under the brand DYE CNC based in California. Dave Dehaan started the company by producing barrels for paintball markers, using his garage as a workshop. He supplied barrels to the California Ironmen and Team Avalanche, who at that time were two of the most dominant teams in Professional paintball. From these humble beginnings, DYE went on to become an International concern that went on to manufacture an extensive range of paintball markers, loaders, playing & casual clothing, protective gear, goggles and luggage and created an economy focused offshoot brand Proto Paintball. Their range of products is typically updated each year. In 2005, the company was praised as one of the industry's largest paintball manufacturers. The company has offices in London, Taiwan and Germany.\nMarkers.\nDYE markers are considered to be high end tournament level markers and have been used professionally since their inception. Their most notable marker the Matrix line is a spool valve operated electropneumatic marker that featured smooth \"flowing\" milling to the aluminum body and a soft shot profile. Many notable professional teams have used DYE markers including Los Angeles Ironmen, Tampa Bay Damage and Red Legion.\nHistory.\nDYE Precision was founded by Dave and Rhonda DeHaan in 1994. DYE stands for Dave \"Youngblood\" Enterprises.\nIn 2006, DYE Precision sponsored a team, XXTIONEER, at the 2006 Paintball World Cup Asia.\nIn March 2009, DYE Precision manufactured the Baltimore Trauma with 2009 Mid-Atlantic Open jerseys.\nIn March 2010, the company allowed teams at the 2010 Paintball Sports Promotions World Cup to experience the new 2010 models free of charge. In April 2010, DYE Precision manufactured the jerseys for professional paintball team Portland Naughty Dogs. and later presented them with a limited special edition Naughty Dogs NT paintball gun. That same month, DYE Precision co-hosted the National Collegiate Paintball Association tournament in Central Florida.\nIn January 2011, DYE Precision signed a multi-year agreement with professional paintball team Chattanooga CEP.\nIn October 2012, DYE Precision signed a multi-year agreement with Ukrainian professional paintball team Hulk Kiev\nIn November 2012, the company purchased Pro-Tec, a helmet manufacturing company, from apparel and sports equipment company Vans for an undisclosed amount.\nIn December 2015, DYE Precision sold off Pro-Tec, a helmet manufacturing company, to Bravo Sports, a sporting goods and manufacturing brand for an undisclosed amount.", "Engineering,_Manufacturing": 0.9994126558, "qwen": "Yes"}
{"id": "57003662", "revid": "105732", "url": "https://en.wikipedia.org/wiki?curid=57003662", "title": "Extrusion welding", "text": "Extrusion welding is one of the processes used to weld thermoplastics and composites, developed in the 1960s as an evolution of hot gas welding. It can be a manual or automated process.\nThe process uses a welding head that has a nozzle for hot air and an extruder that pushes filler material out. The process entails heating the joining (faying) surfaces and adding molten or plasticized filler material (extrudate) by extruding it through a die (shoe). The process applies extrudate with pressure to ensure good bonding, and then allows the part to cool.\nWelding steps.\nThe steps of this welding process are similar to other plastic welding processes and involve:\nPreheat is required at the initial start of the weld. This is typically achieved by using the hot air nozzle on the welding gun and fanning the starting area. Once welding has commenced, proper travel speed and gun angle will ensure that the upcoming faying surface has been sufficiently preheated.\nThe filler material is a polymer that comes in the form of spooled strands or in pellets.\nJoint configuration.\nMost weld joints are designed to be a single pass, but plates over 30 mm thickness will require multiple passes. Because most passes are designed to be done in a single pass, extrusion welding typically takes less overall time to perform as compared to other plastic welding processes, particularly its predecessor, hot gas welding.\nJoint design include:\nButt joints will be single-V or double-V groove with 45-90° and 0-2 mm root gap. If welding a double-V groove, welding will need to be performed in a minimum of two passes.\nT-joints will normally have a single bevel of 45-60° and 0-2 mm root gap.\nBoth TYK connections for piping and fillet welds are achievable as well.\nApplications.\nExtrusion welding is an attractive process for applications that take advantage of its ability to weld thick sections quickly. For some applications, especially where there are large geometry parts where more traditional plastic welding methods (such as hot plate welding) is not possible, extrusion welding is the only feasible and cost effect option. In particular, tanks for liquid waste, corrosive materials, water supply are common applications. As long as a sealing bond is achieved, extrusion welding can be used for waterproofing applications as well.\nMaterials.\nExtrusion welding has seen the most success in welding different types of polyolefins.\nCommon materials welded with this process are:\nEquipment.\nWhile there are various forms of extrusion welding equipment, there are three main components that every extrusion welding setup contains:\nExtruder.\nThe extruder is the part of the setup that actually feeds extrudate through the system. The setup of the extruder depends on if the extrudate is in pellet or in spooled strand form. When spooled strands are used, the spool is fed through a tube into the welding head and then exits through the shoe. When pellets are used for extrudate, the pellets are fed into a hopper, then a heated spiral extruder forces them through the welding head and out through the shoe as molten filler material. Pellets can only be used when welding is being performed in the flat or horizontal position.\nRadiant heat source.\nFor most applications, the radiant heat source will be hot air. The air is heated and blown through a nozzle that is part of the weld head setup. Different nozzle geometries are available, and the welder may select a certain nozzle depending on the joint configuration. Although there is a general purpose nozzle, certain nozzles ensure more thorough or more focused heating of a given joint type. Although hot air is usually used as the means for preheat, halogen lamps are sometimes used as the means for preheating the faying surface.\nWelding shoe.\nThe welding shoe is the die at the end of the feed through which the filler material is being extruded. Typically, the shoe is made out of polytetrafluoroethylene (PTFE) because of PTFE's non-stick properties. Welding shoes come in various shapes and sizes depending on the joint design that is being welded. The welding shoe will also have guide nipples that prevent the molten extrudate from flowing in an undesired direction.\nWelding parameters.\nThere are several main welding parameters, and each of them have a different bearing on the welding process. Some are dependent on the welder, whereas others can be set on the machine before welding commences. Getting a good balance of each parameter is the key to achieving strong and aesthetic welds. Automation or skill by an experienced welder, coupled with properly set parameters will result in consistent and reproducible welds.\nWelding speed.\nWelding speed or travel speed, is the rate at which the weld is traversing down the weld joint. For an automated system, the welding speed can be set before the machine starts to go. With a manual setup, the travel speed will depend on the welder. If the travel speed is too fast, there won't be enough filler material deposited, resulting in a small weld bead. Traveling too quickly may also not provide enough time to get sufficient heat to the faying surfaces. This will result in poor adhesion of the extrudate to the faying surface. This poor adhesion leads to poor strength of the welded part. Conversely, if the travel speed is too low, then too much filler material will be deposited, resulting in an unaesthetic weld and potentially flash formation which will then need to be removed.\nPosition of the welding head.\nPosition of the welding gun is essential to ensure that the extrudate is being deposited in the right area. When a manual system is being used, the welder will need to ensure that the welding head is aimed correctly. If there is misalignment between the gun and the joint, the material will not be deposited to the correct area. To help guide the welder, the weld shoe will be specifically shaped for a given joint geometry so that the position is maintained throughout welding.\nTemperature of the extrudate.\nThe temperature of the extrudate will be set on the extruder before welding begins. The temperature must be high enough such that the extrudate will be sufficiently fluid to flow, but not so high that the polymer filler material will begin to chemically breakdown. The ideal temperature for the extrudate will be dependent on what polymer being used.\nAirflow rate and air temperature.\nStudies by have found that airflow rate and temperature are the two biggest factors in the development of creep strength of the welded parts. This is because airflow rate and air temperature are the two biggest factors in development of a melt layer prior to welding. The melt layer is the layer of molten polymer on top of the faying surface. When the melt layer reaches an ideal thickness for welding, the creep strength of the welds increase dramatically. Like with the temperature of the extrudate however, the ideal temperature and airflow rate for base material will depend on what polymer is being welded. Additionally, airflow may be altered depending on the shape of the nozzle.\nExtrusion rate.\nExtrusion rate is how much extrudate is actually being transferred into the joint at any given time. Along with extrudate temperature and airflow rate/temperature, extrusion rate must be balanced in order to achieve ideal weld properties. If not enough material is added, then there won't be complete fusion of the joint. Conversely, if too much filler is added, then there is potential to create flash or sharp point at the toes of the weld cap. These would act as stress risers and dramatically decrease the strength of the weld both in dynamic and fatigue loading.\nAdvantages and disadvantages.\nAdvantages.\nThe main advantage of extrusion welding is that it can achieve very high deposition rates of filler material into a joint, thus cutting down on cycle time. As compared to hot gas welding, which is a polymer welding process that could have many of the same applications, the time to completion for a weld is as much as 5-6x faster.\nWith proper parameters, the fusion areas of the weld will actually not be the weakest part of a given fabricated polymeric part.\nBecause many of the main welding parameters are preset on the machine, getting consistent high quality welds is possible.\nDisadvantages.\nIf using manual extrusion welding, the welder must have a certain amount of skill in order to produce sound welds. This is especially true when welding in vertical or overhead positions. Furthermore, a manual machine could be as heavy as 12kg, which would prove to be cumbersome.", "Engineering,_Manufacturing": 0.9999969006, "qwen": "Yes"}
{"id": "57012543", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=57012543", "title": "Cumulative quantities (logistics)", "text": "Cumulative quantities are a concept in logistics that involves adding up required materials quantities over a defined time-window that can be drawn as a 'cumulative curve'. This concept is applied in serial production and mainly used in the automotive industry to plan, control and monitor production and delivery. The concept is sometimes called 'Cumulative Production Figures Principle' (CPGP). \nClosed-loop-cycle.\nThe Concept of Cumulative Quantities (CCQ) uses the feedback mechanism of a closed loop, which can be found in industrial, engineering and electronic systems. The target requirements are summarized for each time-interval and compared with the actual values for closed-loop control. Positive cumulative deviation for a certain time-interval requires no further order, while negative deviations require a new order. To \"calm\" production and material flow upper and lower tolerance boundaries are defined and only if these boundaries are violated is a renewed order.\nTo check the entire production and material flow 'reporting limits' can be defined at a chosen counting point and if a limit is exceeded a concerned 'alert' is issued. The logistics staff has to explain the reason for the 'alert'. If the reason is correct and traceable no further action is needed. If mistakes are present in the database, data processing or in data-acquisition appropriate counter-measures are needed. Examples for mistakes or failures wrong primary demand or bad forecasting, mistakes in Bill of Material or master data, old Master Production Schedule, inaccurate or delayed data acquisition, calculation mistakes, mounting of incorrect parts at assembly line.\nCounting points.\nTarget-actual-control-loop uses exactly defined counting points that demarcate the next-following intervals along the supply chain. The cumulative differences of next-following counting points show the quantities of material items which traverse the Interval and therefore offer transparency of the inventory of an item along the entire supply chain.\nSupply chain.\nCumulative quantities are a part of official EDI-formats (e.g. EDIFACT - DELFOR) that are widely used by OEMs and their suppliers. Normally the data acquisition at 'goods receipt' are used for communication between consignee and goods dispatcher.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "57019837", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=57019837", "title": "Counting point", "text": "In logistics, a counting point (CP; also known as a status point, data acquisition point, check point, or control point) is a certain spot designated for planning, controlling, and monitoring material flow items (e.g. single parts, assembly groups, final products, bins, racks, containers, and freight carriers).\nInstallation.\nIf the production and material flow gets more and more complex then more counting points must be installed in the process of transport, shipping, and manufacturing. Especially check points for quality control and quality assurance can be used outstandingly as counting points but also data acquisition points in material handling processes. For better planning and monitoring of material flow items it is helpful to order all counting points in such a way that the requirements of an ideal Boolean Interval (mathematics) Algebra can be fulfilled. Boolean intervals are half-opened and a counting point lays always inside at the beginning and the ending lays outside and is the entry-point of the next-following interval. Such an interval can represent any kind of stretch in production and material flow e.g. an assembly line, a storage or warehouse, a transport route etc. Alternative production and transportation stretches are mapped as parallel intervals, which are logical equivalent but have their own different data acquisition points. If a flow item passes a certain CP it has left the preceding interval and stays in the concerned interval at the same time. By this it can be assured that a flow object can stay only in one interval at a certain moment which is also true and evident for parallel intervals. This kind of mapping material flow structure is necessary for a consistent calculation of the lead-time and complete cycle time for flow items which is extremely important not only for material flow planning but also for production planning and manufacturing operations management in general.\nUsage.\nCounting points are used in different logistic areas like transportation, material handling, goods receipt, and goods issue at the border of a plant, because this is often transfer of ownership. Other well-known counting points are receiving and issuing material items at the border of a storage or warehouse. Counting points play an important rule also in manufacturing and production scheduling and different concepts of material requirements planning (e.g for the concept of cumulative quantities and the gross-net-method. Counting points also appear in the automotive industry where the production flow of a car is controlled, scheduled, and monitored continuously at exactly-defined check points for different manufacturing departments and shops and where the data is used for scheduling and optimization.", "Engineering,_Manufacturing": 1.0000032187, "qwen": "Yes"}
{"id": "57020348", "revid": "1162037513", "url": "https://en.wikipedia.org/wiki?curid=57020348", "title": "Aluminium joining", "text": "Aluminium alloys are often used due to their high strength-to-weight ratio, corrosion resistance, low cost, high thermal and electrical conductivity. There are a variety of techniques to join aluminium including mechanical fasteners, welding, adhesive bonding, brazing, soldering and friction stir welding (FSW), etc. Various techniques are used based on the cost and strength required for the joint. In addition, process combinations can be performed to provide means for difficult-to-join assemblies and to reduce certain process limitations.\nMechanical fasteners.\nA simple and cheap method to join aluminium is using mechanical fasteners (i.e. bolts and nuts). Normally a hole is drilled into the base material and a fastener is placed inside. This type of joiner requires some type of overlapping material for a joint to be made. Aluminium rivets or bolts and nuts can be used; however, high-stress applications would require higher strength fastener material such as steel. This could lead to galvanic corrosion of different materials which have varying electrochemical potential. Significant corrosion would weaken the assembly over time and possibly lead to failure. In addition, different materials could result in thermal fatigue cracking from differing coefficients of thermal expansion. As the assembly is repeatedly heated stresses can build up and enlarge the mounting hole. A common place mechanical fasteners are used is riveting of aluminium panels on airplane exteriors.\nAdhesive bonding.\nAluminium can be joined with a variety of adhesives. Aluminium may require some level of surface preparation and passivation to remove any unwanted chemical from the surface. Passivation could be as simple as rubbing alcohol or ultrasonic cleaning. Before bonding, a dry fit can confirm proper fitting of the components. Adhesives may require heat, pressure, or both during curing.\nSurface preparation.\nIn order for a proper adhesive bond, some surface preparation is necessary. A surface cleaning to remove any impurities is made. The surface of the parts to be joined may be roughened with an abrasive such as sandpaper, providing interlocking surface asperities and increasing surface area for bonding. A chemical treatment may also be needed to increase the surface energy of the adherent and remove the oxide layer. Aluminium oxide is weakly bonded to the underlying aluminium metal; without oxide removal the adhesive joint is dramatically weakened. Oxide layers can separate from the metal substrate; a key principle for adhesive failure theory is Bikerman weak boundary layer. One way to strengthen the oxide layer and prevent oxide-to-substrate failure is to anodize the material, creating a strong hexagonal oxide layer with additional surface area for adhesive joining.\nType of adhesives.\nAdhesive selection can be dictated based on cost, strength and needed ductility. Hobbyists commonly use cyanoacrylate (super glue), epoxy, or JB Weld. Silicone may also be used in an application in which waterproofing is needed.\nWelding.\nMost aluminium alloys can be joined by welding together; however, certain aircraft-grade aluminium and other special alloys are unweldable using conventional methods. Aluminium is commonly welded with gas metal arc welding (GMAW) and gas tungsten arc welding (GTAW). Due to aluminium's oxide layer, a positive polarity is needed to break up the surface to ensure a proper weld. Alternating current (AC) is also used to allow the benefits of a negative polarity which provides penetration and enough positive polarity for a containment-free weld. More details on welding parameters structural aluminium welding codes can be found in AWS D1.2.\nAluminium welding typically creates a softened region in the weld metal and heat-affected zone. Additional heat treatments may be needed to obtain a material acceptable for a specific application. Industrial welding is also commonly used in joining aluminium: friction stir welding, laser welding, and ultrasonic welding are some of the many processes used.\nBrazing and soldering.\nAluminium can be brazed or soldered to almost any material including concrete, ceramics, or wood. Brazing and soldering can be carried out manually or by an automated technique. Manual aluminium brazing can be difficult as there is no observable colour change before melting. As with other techniques, aluminium's strong oxide can prevent proper bonding. Strong acids and bases can be used to weaken the oxide, or aggressive fluxes may be used. Brazing alloys for aluminium must melt below aluminium's melting temperature of 660 °C. Aluminium alloys with high magnesium content can \"poison\" fluxes and depress the melting temperature, which can cause a weak joint. In some cases, the aluminium parts can be clad with a different material and brazed with a more common technique and filler material. Brazed joints require overlapping of parts; the amount of overlap can greatly affect the strength of the joint.\nFriction stir welding.\nFriction stir welding (FSW) is a solid-state joining process that uses a non-consumable tool to join two facing workpieces without melting the workpiece material. Heat is generated by friction between the rotating tool and the workpiece material, which leads to a softened region near the FSW tool. While the tool is traversed along the joint line, it mechanically intermixes the two pieces of metal, and forges the hot and softened metal by the mechanical pressure, which is applied by the tool, much like joining clay or dough. It was primarily used on wrought or extruded aluminium, particularly for structures which need very high weld strength.", "Engineering,_Manufacturing": 1.0000077486, "qwen": "Yes"}
{"id": "40181153", "revid": "45902013", "url": "https://en.wikipedia.org/wiki?curid=40181153", "title": "Sandvik Coromant", "text": "Sandvik Coromant is a Swedish company that supplies cutting tools and services to the metal cutting industry.\nSandvik Coromant is headquartered in Sandviken, Sweden and is represented in more than 150 countries with some 7900 employees worldwide. It is part of the business area Sandvik Machining Solutions within the global industrial group Sandvik.\nMetalworking focus.\nSandvik Coromant produces an extensive range of metal-cutting tools:\nHistory in brief.\n1942: The company began as a small production unit for cemented carbide tools in Sandviken, Sweden when Wilhelm Haglund is assigned the job as manager of the unit. However, in 1951, new innovations and manufacturing methods lead to the establishment of a more industrialized unit in Gimo, Sweden.\n1957: Scrapers become the first product with mechanically clamped “indexable inserts” or “throw-away inserts”. The birth of the T-Max holder and the use of indexable inserts is the start of a big change in the practice and productivity of machining.\n1969: Heat-resistant Gamma Coating, or GC, is introduced as a grade, revolutionizing turning, milling, and drilling with previously unmatched metal cutting performance.\n1972: The Multi-Service marketing campaign sees the light of day, and the yellow coat becomes an important symbol. Tool-pool, machine-adapted tool recommendations and mini-catalogues are made available.\n1990: Coromant Capto, a single holding system for both rotating and stationary spindles, is introduced. This ground-breaking invention provided a new and efficient means of combining and organizing tooling while reducing tool-changing time in machinery. Today Coromant Capto (Latin for “I am gripping”) is an established system and an ISO standard around the world.\n1997: Sandvik Coromant offers to repurchase used cemented carbide inserts for recycling, underlining the company's commitment to environmental responsibility.\n2008: Sandvik Coromant acquires Norwegian anti-vibration tool developer Teeness. The unique Silent Tools damping adaptors allow for increased cutting parameters and a more secure, vibration-free process.\n2013: Sandvik Coromant researchers discover that it is possible to control coating crystals at an atomic level to create a uniform, tightly packed, thermal-protected coating for new levels of hardness: Inveio coating technology is introduced.\n2016: CoroPlus makes its first appearance, used in the design, planning, monitoring of machining performance and the optimization of machining processes.\n2017: PrimeTurning is introduced, a new methodology enabling turning in all directions.\n2019: The production unit in Gimo, Sweden, is officially announced as a \"lighthouse\" by World Economic Forum as a role model in industry 4.0.\nResearch and development.\nSandvik Coromant employs 500 researchers working at research and development centers around the globe. In total, some 60 research and testing facilities work in close cooperation with machine tool manufacturers, machining tool agents, and customers across a wide range of industries.\nTraining and education.\nTraining\nAmong its e-learning courses, Sandvik Coromant offers Metalcutting Technology Training; some 35,000 users are registered for the program.\nEducation\nSandvik Coromant collaborates with numerous educational institutions and organizations worldwide as part of its mission to promote the ongoing development of industry knowledge and education.\nPartnerships\nSandvik Coromant is a member of the Advanced Manufacturing Research Centre (AMRC) in the UK, working with the centre's partners: Boeing, Rolls-Royce and the University of Sheffield. The AMRC shares research and support in areas of assembly, composite materials, structural testing, and advanced machining for the aerospace industry.\nSandvik Coromant has also partnered with the Commonwealth Center for Advanced Manufacturing as one of its originating industry members, as well as the Connecticut Center for Advanced Technology in the United States and the Manufacturing Technology Center in the UK.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "25137369", "revid": "8942941", "url": "https://en.wikipedia.org/wiki?curid=25137369", "title": "Palletizer", "text": "A palletizer or palletiser is a machine which provides automatic means for stacking cases of goods or products onto a pallet.\nManually placing boxes on pallets can be time consuming and expensive; it can also put unusual stress on workers. The first mechanized palletizer was designed, built, and installed in 1948 by a company formerly known as Lamson Corp.\nThere are specific types of palletizers including the row-forming which were introduced in the early 1950s. In row-forming palletizing applications loads are arranged on a row forming area and then moved onto a different area where layer forming takes place. This process repeats until a full layer of goods and products are configured to be placed on a pallet.\nThe in-line palletizer was developed in the 1970s when higher speeds were needed for palletizing. This palletizer type utilizes a continuous motion flow divider that guides the goods into the desired area on the layer forming platform.\nRobotic palletizers were introduced in the early 1980s and have an end of arm tool (end effector) to grab the product from a conveyor or layer table and position it onto a pallet. Both conventional and robotic palletizers can receive product at a high elevation, typically , or low \"floor level\" elevation of . The end of arm tooling has evolved in recent years to accommodate a variation of pack pattern and package types.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "14410264", "revid": "34026143", "url": "https://en.wikipedia.org/wiki?curid=14410264", "title": "Proximity communication", "text": "Proximity communication is a Sun microsystems technology of wireless chip-to-chip communications. Partly by Robert Drost and Ivan Sutherland. Research done as part of High Productivity Computing Systems DARPA project.\nProximity communication replaces wires by capacitive coupling, promises significant increase in communications speed between chips in an electronic system, among other benefits. Partially funded by a $50 million award from the Defense Advanced Research Projects Agency.\nComparing traditional area ball bonding, proximity communication has one order smaller scale, so it can be two order denser (in terms of connection number/PIN) than ball bonding. This technique requires very good alignment between chips and very small gaps between transmitting (Tx) and receiving (Rx) parts (2-3 micrometers), which can be destroyed by thermal expansion, vibration, dust, etc.\nChip transmitter consists (according to presentation slide) of big 32x32 array of very small Tx micropads, 4x4 array of bigger Rx micropads (four times bigger than tx micropad), and two linear arrays of 14 X vernier and 14 Y vernier.\nProximity communication can be used with 3D packing on chips in Multi-Chip Module, allowing to connect several MCM without sockets and wires. \nSpeed was up to 1.35 Gbit/s/channel in tests of 16 channel systems. BER < 10−12. Static power is 3.6 mW/channel, dynamic power is 3.9 pJ/bit.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "14419104", "revid": "8372814", "url": "https://en.wikipedia.org/wiki?curid=14419104", "title": "Rivet gun", "text": "A rivet gun, also known as a rivet hammer or a pneumatic hammer, is a type of tool used to drive rivets. The rivet gun is used on rivet's \"factory head\" (the head present before riveting takes place), and a bucking bar is used to support the tail of the rivet. The energy from the hammer in the rivet gun drives the work and the rivet against the bucking bar. As a result, the tail of the rivet is compressed and work-hardened. At the same time the work is tightly drawn together and retained between the rivet head and the flattened tail (now called the \"shop head\", or buck-tail, to distinguish it from the factory head). Nearly all rivet guns are pneumatically powered. Those rivet guns used to drive rivets in structural steel are quite large while those used in aircraft assembly are easily held in one hand. A rivet gun differs from an air hammer in the precision of the driving force.\nRivet guns vary in size and shape and have a variety of handles and grips. Pneumatic rivet guns typically have a regulator which adjusts the amount of air entering the tool. Regulated air entering passes through the throttle valve which is typically controlled by a trigger in the hand grip. When the trigger is squeezed, the throttle valve opens, allowing the pressurized air to flow into the piston. As the piston moves, a port opens allowing the air pressure to escape. The piston strikes against the rivet set. The force on the rivet set pushes the rivet into the work and against the bucking bar. The bucking bar deforms the tail of the rivet. The piston is returned to the original position by a spring or the shifting of a valve allowing air to drive the piston back to the starting position.\nSlow-hitting.\nThe slow-hitting gun strikes multiple blows as long as the trigger is held down. The repetition rate is about 2,500 blows-per-minute (bpm). It is easier to control than a one-hit gun. This is probably the most common type of rivet gun in use.\nFast-hitting gun.\nThe fast-hitting gun strikes multiple light-weight blows at a high rate as long as the trigger is held down. These are repeated in the range of 2,500 to 5,000 bpm. The fast-hitting gun, sometimes referred to as a vibrator, is generally used with softer rivets.\nCorner riveter.\nThe corner riveter is a compact rivet gun that can be used in close spaces. The rivet is driven at right-angles to handle by a very short barreled driver.\nSqueeze riveter.\nThis gun is different from the above rivet guns in that the air pressure is used to provide a squeezing action that compresses the rivet from both sides rather than distinct blows. The squeeze riveter can only be used close to the edge because of the limited depth of the anvil. Once properly adjusted, the squeeze riveter will produce very uniform rivet bucks. The stationary (fixed) jaw is placed against the head and the buck is compressed by the action of the gun.\nPop-rivet gun.\nA pop rivet gun is made to apply pop rivets to a workpiece, and was invented in 1916 by Hamilton Wylie. This type of rivet gun is unique in its operation, because it does not hammer the rivet into place. Rather, a pop rivet gun will form a rivet in-place.\"\nThe gun is fed over the rivet's mandrel (a shaft protruding from the rivet head) and the rivet tail is inserted into the work. When the gun is actuated (typically by squeezing the handle), a ball on the rivet's tail is drawn towards the head, compressing a metal sleeve between the ball and the head. This forms another \"head\" on the opposing side to the workpiece, drawing the work together and holding it securely in place. The mandrel has a weak point that breaks, or \"pops\" when the riveting process is complete. This style of rivet does not require the use of a bucking bar, because the force applied is away from the work. ", "Engineering,_Manufacturing": 0.9976875186, "qwen": "Yes"}
{"id": "292280", "revid": "1223123", "url": "https://en.wikipedia.org/wiki?curid=292280", "title": "Perforation", "text": "A perforation is a small hole in a thin material or web. There is usually more than one perforation in an organized fashion, where all of the holes collectively are called a \"perforation\". The process of creating perforations is called perforating, which involves puncturing the workpiece with a tool.\nPerforations are usually used to allow easy separation of two sections of the material, such as allowing paper to be torn easily along the line. Packaging with perforations in paperboard or plastic film is easy for consumers to open. Other purposes include filtrating fluids, sound deadening, allowing light or fluids to pass through, and to create an aesthetic design.\nVarious applications include plastic films to allow the packages to breathe, medical films, micro perforated plate and sound and vapor barriers.\nProcesses.\nPins and needles.\nRotary pinned perforation rollers are precision tools that can be used to perforate a wide variety of materials. The pins or needles can be used cold or heated. Cold perforation tools include needle punches.\nThere are a handful of manufacturers that specialize in hot and cold needle perforation tooling and equipment. In materials that have elasticity this can result in a \"volcano\" hole that is preferred in many applications.\nPinned rollers can be made from a variety of materials, including plastic, steel, and aluminum.\nIn more brittle films, cold perforation can cause slitting rather than creating a round hole, which can jeopardize the material's integrity under pressure. The solution to this is often heating the pin; i.e. hot pin perforation. Hot perforation melts a hole in the material, causing a reinforced ring around the hole. Hot needle perforation also assists when high density pin patterns are utilized, as the heat aids the perforation of the material.\nDie and punch.\nDie and punch sets can be used for thicker materials or materials that require large holes; this process is the most common for metalworking. The workpiece is sheared by pressing (either by machine or hand tool) the punch through the workpiece and into the die. The middle section of the workpiece is scrap; commonly known as the chad in paper and similar materials. The punch and die are shaped to produce the desired shaped hole. The clearance (the distance between the outside circumference of the punch and the inner circumference of the die) must be properly maintained to ensure a clean cut. Burrs are produced on the side of the workpiece that is against the die.\nCommon applications are fruit and vegetable bags, hole punching and ticket punching.\nLaser perforation.\nLaser cutting can place many precise holes in a web. Laser perforations look similar in many respects to hot needle perforations. However, laser systems are expensive. The big advantage of laser perforation is the consistency of the hole size, compared to mechanical perforation. This is very important in modified atmosphere packaging for fresh produce. The laser perforation is often carried out on roll slitting machines (slitter rewinder) as the printed material is slit down to the finished roll size.\nApplications.\nPerforation frequently refers to the practice of creating a long series of holes or slits so that paper or plastics can be torn more easily along a given line: this is used in easy-open packaging. Since the creation of perforation devices in the 1840s and 1850s, it has seen use in several areas.\nPostage stamps are one common application of this, where small round holes are cut in lines to create individual pieces. Perforations on stamps are rather large, in the order of a millimeter, in comparison other perforated materials often have smaller holes.\nIt is common for cheque-books, notebooks and legal pads to have perforations making it easier to tear out individual pages or leaves. Perforation is used in ways to separate loose leaf (or even a form of graph paper from a ringed binder). A fine perforation next to the rings allows the page to be separated from the book with no confetti.\nScrewcaps on glass or plastic bottles are sealed with a ring at the bottom of the cap attached by perforation. Twisting the cap has the effect of rupturing the material between the perforations and indicating that the original seal has been broken.\nThe edges of film stock are perforated to allow it to be moved precise distances at a time continuously. Similarly, punched cards for use in looms and later in computers input and output devices in some cases were perforated to ensure correct positioning of the card in the device, and to encode information.\nPerforation of steel strips is used in the manufacture of some zesters and rasps.\nHistorically, perforation patterns other than linear were used to mark stamps. A series of patents had been issued in the late 19th century for perforation machines to be used on rail lines for ticketing. Libraries and private collections used similar perforating stamps to mark ownership of books. End sheets, title pages, and image plates were punched with the namesake of the collection. Today, similarly elaborate perforation patterns continue to be used in orienteering.\nBread bags for some bread often have micro-perforations in the plastic, which is supposed to keep the bread fresh by releasing excess moisture. Similarly, bags of concrete use small perforations to allow air to escape while they are being filled.", "Engineering,_Manufacturing": 0.999828279, "qwen": "Yes"}
{"id": "293079", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=293079", "title": "Actuator", "text": "An actuator is a component of a machine that is responsible for moving and controlling a mechanism or system, for example by opening a valve. In simple terms, it is a \"mover\".\nAn actuator requires a control device (controlled by control signal) and a source of energy. The control signal is relatively low energy and may be electric voltage or current, pneumatic, or hydraulic fluid pressure, or even human power. Its main energy source may be an electric current, hydraulic pressure, or pneumatic pressure. The control device is usually a valve. When it receives a control signal, an actuator responds by converting the source's energy into mechanical motion. In the \"electric\", \"hydraulic\", and \"pneumatic\" sense, it is a form of automation or automatic control.\nThe displacement achieved is commonly linear or rotational, as exemplified by linear motors and rotary motors, respectively. Rotary motion is more natural for small machines making large displacements. By means of a leadscrew, rotary motion can be adapted to function as a linear actuator (a linear motion, but not a linear motor). \nTypes of actuators.\nSoft actuator.\nA soft actuator is one that changes its shape in response to stimuli including mechanical, thermal, magnetic, and electrical. Soft actuators mainly deal with the robotics of humans rather than industry which is what most of the actuators are used for. For most actuators they are mechanically durable yet do not have an ability to adapt compared to soft actuators. The soft actuators apply to mainly safety and healthcare for humans which is why they are able to adapt to environments by disassembling their parts. This is why the driven energy behind soft actuators deal with flexible materials like certain polymers and liquids that are harmless to humans.\nHydraulic.\nThe hydraulic actuator consists of cylinder or fluid motor that uses hydraulic power to facilitate mechanical operation. The mechanical motion gives an output in terms of linear, rotatory or oscillatory motion. As liquids are nearly impossible to compress, a hydraulic actuator can exert a large force. The drawback of this approach is its limited acceleration.\nThe hydraulic cylinder consists of a hollow cylindrical tube along which a piston can slide. The term \"single acting\" is used when the fluid pressure is applied to just one side of the piston. The piston can move in only one direction, a spring being frequently used to give the piston a return stroke. The term \"double acting\" is used when pressure is applied on each side of the piston; any difference in force between the two sides of the piston moves the piston to one side or the other.\nPneumatic.\nPneumatic actuators enable considerable forces to be produced from relatively small pressure changes. Pneumatic energy is desirable for main engine controls because it can quickly respond in starting and stopping as the power source does not need to be stored in reserve for operation. Moreover, pneumatic actuators are cheaper, and often more powerful than other actuators. These forces are often used with valves to move diaphragms to affect the flow of air through the valve.\nThe advantage of pneumatic actuators consists exactly in the high level of force available in a relatively small volume. While the main drawback of the technology consists in the need for a compressed air network composed of several components such as compressors, reservoirs, filters, dryers, air treatment subsystems, valves, tubes, etc. which makes the technology energy inefficient with energy losses that can sum up to 95%\nElectric.\nSince 1960, several actuator technologies have been developed, Electric actuators can be classified in the following groups:\nElectromechanical actuator (EMA).\nIt converts the rotational force of an electric rotary motor into a linear movement to generate the requested linear movement through a mechanism either a belt (Belt Drive axis with stepper or servo) or a screw (either a ball or a lead screw or planetary roller screw )\nThe main advantages of electromechanical actuators are their relatively good level of accuracy with respect to pneumatics, their possible long lifecycle and the little maintenance effort required (might require grease). It is possible to reach relatively high force, on the order of 100 kN.\nThe main limitation of these actuators are the reachable speed, the important dimensions and weight they require.\nWhile the main application of such actuators is mainly seen in health care devices and factory automation.\nElectrohydraulic actuator.\nAnother approach is an electrohydraulic actuator, where the electric motor remains the prime mover but provides torque to operate a hydraulic accumulator that is then used to transmit actuation force in much the same way that diesel engine/hydraulics are typically used in heavy equipment.\nElectrical energy is used to actuate equipment such as multi-turn valves, or electric-powered construction and excavation equipment.\nWhen used to control the flow of fluid through a valve, a brake is typically installed above the motor to prevent the fluid pressure from forcing open the valve. If no brake is installed, the actuator gets activated to reclose the valve, which is slowly forced open again. This sets up an oscillation (open, close, open ...) and the motor and actuator will eventually become damaged.\nLinear motor.\nLinear motors are different from electromechanical actuators, they work with the same principle as electric rotary motors, in effect it can be thought as a rotary motor which has been cut and unrolled. Thus, instead of producing a rotational movement, they produce a linear force along their length. Because linear motors cause lower friction losses than other devices, some linear motor products can last over a hundred million cycles.\nLinear motors are divided in 3 basic categories: flat linear motor (classic), U-Channel linear motors and Tubular linear motors.\nLinear motor technology is the best solution in the context of a low load (up to 30Kgs) because it provides the highest level of speed, control and accuracy.\nIn fact, it represents the most desired and versatile technology. Due to the limitations of pneumatics, the current electric actuator technology is a viable solution for specific industry applications and it has been successfully introduced in market segments such as the watchmaking, semiconductor and pharmaceutical industries (as high as 60% of the applications. The growing interest for this technology, can be explained by the following characteristics:\nThe main disadvantages of linear motors are:\nRotary motor.\nRotary motors are actuators that use a piece of energy to form an oscillatory motion at a certain angle of movement. Rotary actuators can have up to a rotation of 360 degrees. This allows it to differ from a linear motor as the linear is bound to a set distance compared to the rotary motor. Rotary motors have the ability to be set at any given degree in a field making the device easier to set up still with durability and a set torque.\nRotary motors can be powered by 3 different techniques such as Electric, Fluid, or Manual. However, Fluid powered rotary actuators have 5 sub-sections of actuators such as Scotch Yoke, Vane, Rack-and-Pinion, Helical, and Electrohydraulic. All forms have their own specific design and use allowing the ability to choose multiple angles of degree.\nApplications for the rotary actuators are just about endless but, will more than likely be found dealing with mostly hydraulic pressured devices and industries. Rotary actuators are even used in the robotics field when seeing robotic arms in industry lines. Anything you see that deals with motion control systems to perform a task in technology is a good chance to be a rotary actuator.\nThermal or magnetic.\nActuators which can be actuated by applying thermal or magnetic energy to a solid-state material have been used in commercial applications. Thermal actuators can be triggered by temperature or heating through the Joule effect and tend to be compact, lightweight, economical and with high power density. These actuators use shape memory materials such as shape-memory alloys (SMAs) or magnetic shape-memory alloys (MSMAs).\nMechanical.\nA mechanical actuator functions to execute movement by converting one kind of motion, such as rotary motion, into another kind, such as linear motion. An example is a rack and pinion. The operation of mechanical actuators is based on combinations of structural components, such as gears and rails, or pulleys and chains.\n3D printed soft actuators.\nThe majority of the existing soft actuators are fabricated using multistep low yield processes such as micro-moulding, solid freeform fabrication, and mask lithography. However, these methods require manual fabrication of devices, post processing/assembly, and lengthy iterations until maturity in the fabrication is achieved. To avoid the tedious and time-consuming aspects of the current fabrication processes, researchers are exploring an appropriate manufacturing approach for effective fabrication of soft actuators. Therefore, special soft systems that can be fabricated in a single step by rapid prototyping methods, such as 3D printing, are utilized to narrow the gap between the design and implementation of soft actuators, making the process faster, less expensive, and simpler. They also enable incorporation of all actuator components into a single structure eliminating the need to use external joints, adhesives, and fasteners.\nShape memory polymer (SMP) actuators are the most similar to our muscles, providing a response to a range of stimuli such as light, electrical, magnetic, heat, pH, and moisture changes. They have some deficiencies including fatigue and high response time that have been improved through the introduction of smart materials and combination of different materials by means of advanced fabrication technology. The advent of 3D printers has made a new pathway for fabricating low-cost and fast response SMP actuators. The process of receiving external stimuli like heat, moisture, electrical input, light or magnetic field by SMP is referred to as shape memory effect (SME). SMP exhibits some rewarding features such a low density, high strain recovery, biocompatibility, and biodegradability.\nPhotopolymer/light activated polymers (LAP) are another type of SMP that are activated by light stimuli. The LAP actuators can be controlled remotely with instant response and, without any physical contact, only with the variation of light frequency or intensity.\nA need for soft, lightweight and biocompatible soft actuators in soft robotics has influenced researchers for devising pneumatic soft actuators because of their intrinsic compliance nature and ability to produce muscle tension.\nPolymers such as dielectric elastomers (DE), ionic polymer metal composites (IPMC), ionic electroactive polymers, polyelectrolyte gels, and gel-metal composites are common materials to form 3D layered structures that can be tailored to work as soft actuators. EAP actuators are categorized as 3D printed soft actuators that respond to electrical excitation as deformation in their shape.\nExamples and applications.\nIn engineering, actuators are frequently used as mechanisms to introduce motion, or to clamp an object so as to prevent motion. In electronic engineering, actuators are a subdivision of transducers. They are devices which transform an input signal (mainly an electrical signal) into some form of motion.\nCircular to linear conversion.\nMotors are mostly used when circular motions are needed, but can also be used for linear applications by transforming circular to linear motion with a lead screw or similar mechanism. On the other hand, some actuators are intrinsically linear, such as piezoelectric actuators. Conversion between circular and linear motion is commonly made via a few simple types of mechanism including:\nVirtual instrumentation.\nIn virtual instrumentation, actuators and sensors are the hardware complements of virtual instruments.\nPerformance metrics.\nPerformance metrics for actuators include speed, acceleration, and force (alternatively, angular speed, angular acceleration, and torque), as well as energy efficiency and considerations such as mass, volume, operating conditions, and durability, among others.\nForce.\nWhen considering force in actuators for applications, two main metrics should be considered. These two are static and dynamic loads. Static load is the force capability of the actuator while not in motion. Conversely, the dynamic load of the actuator is the force capability while in motion.\nSpeed.\nSpeed should be considered primarily at a no-load pace, since the speed will invariably decrease as the load amount increases. The rate the speed will decrease will directly correlate with the amount of force and the initial speed.\nOperating conditions.\nActuators are commonly rated using the standard IP Code rating system. Those that are rated for dangerous environments will have a higher IP rating than those for personal or common industrial use.\nDurability.\nThis will be determined by each individual manufacturer, depending on usage and quality.", "Engineering,_Manufacturing": 1.0000014305, "qwen": "Yes"}
{"id": "29532716", "revid": "10289486", "url": "https://en.wikipedia.org/wiki?curid=29532716", "title": "Pad cratering", "text": "Pad cratering is a mechanically induced fracture in the resin between copper foil and outermost layer of fiberglass of a printed circuit board (PCB). It may be within the resin or at the resin to fiberglass interface.\nThe pad remains connected to the component (usually a Ball Grid Array, BGA) and leaves a \"crater\" on the surface of the printed circuit board.\nOverview.\nPad cratering most often occurs during dynamic mechanical events such as mechanical shock or board flexure due to In-circuit test (ICT), board depaneling, or connector insertion. However, pad cratering has also been known to occur during thermal shock or even thermal cycling. Susceptibility to pad cratering can be impacted by several factors such as: PCB thickness, PCB laminate material properties, component size and stiffness, component location, and solder alloy selection among other factors.\nTesting.\nIPC-9708 provides three test methods to characterize the pad cratering of a component and PCBA: pin pull, ball pull, and ball shear testing. In the pin pull test a pin is soldered to pads and pulled until fracture. It is a useful test for all pad geometries and is sensitive to board design and materials. The ball pull test is specifically design for BGA components and has a large sensitivity to the solder alloy and joint formation. The ball shear test is also specified for BGA components and involves shearing the solder balls of the BGA. This test is typically the most convenient but is less sensitive to the design and material as compared to the ball pull test. Although IPC-9708 specifies procedures for each test type, the challenge is that no standard pass/fail criteria are defined. This is viewed as application-specific and must be defined by the user based on their design, environment, and reliability requirements.\nAnother applicable test method is IPC/JEDEC-9702, which is a monotonic bend test method used to characterize board level interconnects. This can be relevant for pad cratering resulting from board flexure, however this test method is broader and does not specifically focus on pad cratering failure modes.\nBoard level reliability testing is a common approach to assessing product reliability. Performing temperature cycling, mechanical drop/shock, and vibration testing is a good way to evaluate pad cratering. However, similar to IPC/JEDEC-9702, this can be cost and time intensive and does not specifically focus on pad cratering failure modes.\nDetection and Failure Analysis.\nPad cratering can be difficult to detect during functional testing. This is especially the case with small or partial cracking that can escape testing and cause latent field failures. Even if a component failure is identified, diagnosing the failure mode as pad cratering can be difficult. Conventional nondestructive testing and failure analysis techniques such as visual inspection and X-Ray microscopy may not detect the issue. Electrical characterization is an example of a nondestructive technique that can be useful, however this may not detect an anomaly if there is only partial cracking.\nTypically, pad cratering is detected or confirmed via destructive testing and failure analysis such as dye and pry, acoustic emissions, cross sectioning, and Scanning Electron Microscopy.\nMitigation.\nThere are several mitigation techniques that can used to reduce the risk of pad cratering. The appropriate method(s) is often driven by design and resource constraints.\nLimiting Board Flexure: If cratering is due to mechanical overstress then limiting board flexure is typically the best mitigation technique.\nSimulation: Modeling and simulation can help proactively avoid pad cratering failures. Relevant examples include ICT failures or products with potential for large shock events (i.e. portable electronics). Finite Element Analysis can be done using a physics of failure approach to determine risk of overstress and pad cratering. This proactive approach can rapidly evaluate multiple designs early on, potentially avoiding expensive design changes or warranty costs later on.\nUnderfill, Edge Bonding, and Corner Staking: Epoxies and underfill materials can be added to provide mechanical support and reduce board and solder strain during flexing. This is more common in cases where the component selection and PCBA design are fixed. There are differences between each technique which makes proper understanding of the environment and application important.\nSolder Alloy: Solder alloy selection can impact susceptibility to pad cratering. Typically, pad cratering is considered a high strain rate event with minimal creep, however there is still potential for plasticity in the solder. More compliant solders or those with lower yield points will reduce pad cratering potential by providing additional load sharing.\nBoard Thickness and Laminate Material: Board thickness and laminate material properties such as Young's modulus and Coefficient of Thermal Expansion (CTE) will impact susceptibility to pad cratering.\nBoard Redesign: If pad cratering persists then a redesign may be required. This could include changing component location or adjusting between solder mask defined (SMD) and non-solder mask defined (NSMD) pads.\nExternal links.\nAdditional information on pad cratering in printed circuit boards can be found in the following links:", "Engineering,_Manufacturing": 1.0000030994, "qwen": "Yes"}
{"id": "25398842", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=25398842", "title": "Norwegian Industrial Bank", "text": "The Norwegian Industrial Bank , also known as the Industry Bank, was a Norwegian bank.\nIt had a nationwide mandate as an industrial development bank. It was created in 1936, amid the interwar economic crisis, to supply loans to industry and hotels. The Norwegian state owned about half of the shares. In 1977 it incorporated the loan institution Strukturfinans. In 1993 it merged with the Industry Fund and the Regional Development Fund to form the Norwegian Industrial and Regional Development Fund, now a part of Innovation Norway.", "Engineering,_Manufacturing": 0.9999843836, "qwen": "Yes"}
{"id": "14629026", "revid": "6046731", "url": "https://en.wikipedia.org/wiki?curid=14629026", "title": "Chain conveyor", "text": "A chain conveyor is a type of conveyor system for moving material through production lines.\nOperation.\nChain conveyors use an endless chain both to transmit power and to propel material through a trough, either pushed directly by the chain or by attachments to the chain. The chain runs over sprockets at either end of the trough. Chain conveyors are used to move material up to , and typically under .\nChain conveyors utilize a powered continuous chain arrangement, carrying a series of single pendants. The chain arrangement is driven by a motor, and the material suspended on the pendants are conveyed. Chain conveyors are used for moving products down an assembly line and/or around a manufacturing or warehousing facility.\nChain conveyors are primarily used to transport heavy unit loads, e.g. pallets, grid boxes, and industrial containers. These conveyors can be single or double chain strand in configuration. The load is positioned on the chains, the friction pulls the load forward. Chain conveyors are generally easy to install and have very minimum maintenance for users.\nMany industry sectors use chain conveyor technology in their production lines. The automotive industry commonly uses chain conveyor systems to convey car parts through paint plants. Chain conveyors also have widespread use in the white and brown goods, metal finishing and distribution industries. Chain conveyors are also used in the painting and coating industry, this allows for easier paint application. The products are attached to an above head chain conveyor, keeping products off of the floor allows for higher productivity levels.\nTypes.\nTypes of chain conveyor include apron, drag, plain chain, scraper, flight, and en-masse conveyors.\nDrag conveyor.\nDrag conveyors, variously called \"drag chain conveyors\", \"scraper chain conveyors\" and \"en-masse conveyors\", are used in bulk material handling to move solid material along a trough. They are used for moving materials such as cement clinker, ash, and sawdust in the mining and chemical industries, municipal solid waste incinerators, and the production of pellet fuel.\nThe difference between drag conveyors, scraper conveyors, and flight conveyors largely depends on whether the chain links have obvious flights or paddles attached. In a drag conveyor, the chain moves the material directly, while a flight conveyor uses a series of wood, metal, or plastic flights attached to the chain at regular intervals, which push the material along the trough.\nMultiflexing chain conveyor.\nMultiflexing conveyor systems use plastic chains in many configurations. The flexible conveyor chain design permits horizontal as well as vertical change of direction.", "Engineering,_Manufacturing": 0.9999649525, "qwen": "Yes"}
{"id": "58818220", "revid": "43558034", "url": "https://en.wikipedia.org/wiki?curid=58818220", "title": "Hayes-Wheelwright matrix", "text": "The Hayes-Wheelwright Matrix, also known as the product-process matrix, is a tool to analyze the fit between a chosen product positioning and manufacturing process.\nThe first dimension of the matrix, the product lifecycle, is a measure of the maturity of the product or market. It ranges from highly customized products with low volumes, to highly standardized products with high volume. The second dimension, the process lifecycle, is a measure of the maturity of the manufacturing process. It ranges from highly manual processes with high unit costs (job shop) to highly automated process with low unit costs (continuous flow).\nCompanies can occupy any position in the matrix. However, according to the framework, they can only be successful if their product lifecycle stage is consistent with their process lifecycle stage.\nIt was developed by Robert H. Hayes and Steven C. Wheelwright and published in the \"Harvard Business Review\" in 1979, in the articles titled \"\"Link Manufacturing Process and Product Life Cycles\" and \"The Dynamics of Process-Product Life Cycles\".\"\nUsing the matrix.\nA company's place on the matrix depends on two dimensions – the process structure/process lifecycle and the product structure/product lifecycles. The process structure/process lifecycle is composed of the process choice (job shop, batch, assembly line, and continuous flow) and the process structure (jumbled flow, disconnected line flow, connected line flow and continuous flow). The product structure/product lifecycle refers to the four stages of the product lifecycle from low volume to high volume and the product structure from low standardization to high standardization.\nEach process choice on the diagonal of the matrix comprises different sets of characteristics in consideration of skill level and flexibility of workers and labour intensity. The upper-left modules (project, job shop, batch processes) tend to have higher skilled workers with a larger range of skills for better flexibility and are more labor-intensive compared. It is rare for the upper-left modules to work at full capacity and they use general-purpose equipment. They usually cater to local and/or niche markets. The lower-right manufacturing processes (mass production; assembly line and continuous processes) require only unskilled or semi-skilled workers to monitor and maintain the equipment as they are far more capital intensive processes. The production facilities are also interrelated and require specialized machinery unique to the specific product. They often cater to national markets and can be vertically integrated. The matrix highlights the difficult trade-off between efficiency and flexibility of the operations with the upper-left modules favoring flexibility with high-cost productions and the lower-right modules favoring efficiency with the ability to spread their large fixed costs over a wider base, reducing cost per unit. The product-process matrix affects three aspects of the business.\nDistinctive competence.\nDistinctive competence is a characteristic or aspect of the company that gives it a comparative advantage over its competitors, usually categorized by cost/price, quality, flexibility and service/time. The matrix can be used as a framework to identify and analyze a company's distinctive competence to better inform decisions on processes and alternatives and marketing alternatives.\nFlexibility.\nThe wide range of skilled labor and use of general-purpose equipment allows upper-left processes to have distinctive competence in flexibility in their product/service provided, specifically in unique product designs. Lower-right processes do not have that aspect of flexibility since they rely on specialized machinery with unskilled or semi-skilled workers. However, they have better flexibility when it comes to quantity.\nQuality.\nUpper-left processes excel in quality when it comes to unique designs based on the customers' specifications or if the product is considered artisan. While upper-left processes cater products to specific customers, lower-right processes can take advantage of consistently producing homogeneous products to eliminate flaws and improve designs over time for a more reliability to the end user.\nService/Time.\nUpper-left processes can claim distinctive competence through face-to-face interaction and personal attention while lower-right processes are more time-efficient.\nCost/price.\nBusinesses that use the upper-left processes are likely able to charge higher prices because of their ability to cater to individual customers and to compensate for the skilled labor. Lower-right processes are more cost-efficient because their large volumes allow them to take advantage of economies of scale.\nManagement.\nFirms operating along the diagonal matrix are assumed to perform better than those too far from the diagonal because it impairs them from competing effectively. For example, a commodity produced by a job shop would be economically impractical. There are niche players that do not operate exactly on the diagonal but near it; for example, Rolls-Royce manufactures automobiles using job shop. Management must consider the disadvantages and implications of doing so. Management can also consider the strategic implications of their position on the matrix compared to their competitors. A firm's position on the matrix can change over time; it can predict the consequences of any future products or process changes.\nThe nature of a product can be identified using the matrix. Hayes and Wheelwright illustrate this using a specialized manufacturer of printed circuit boards that produced customized products in low-volumes using an interrelated assembly-line process, placing the business in the undesirable lower-left corner of the matrix. Knowing this, the company concluded its product lay in design capability rather than the circuit boards themselves, which placed them nearer along the diagonal.\nOrganization.\nAnother diagnostic use of the matrix is to organize individual operating units according to the suitable process choice while maintaining the overall coordination of the manufacturing procedure. Most firms use more than one process for a product. For example, batch processing may be more suitable for individual components because of its nature or the volume needed is not sufficient for the line process, but the product itself is constructed on an assembly line. Firms may need separate facilities for the parts or products. Firms can also produce similar products using different process options. Fender Musical Instruments mass-produce electric guitars using the line process while also producing custom guitars using job shop (Fender Custom Shop).\nThe four stages.\nThe Hayes-Wheelwright matrix is a four-stage model; each stage is characterized by the management strategy implemented to exploit the manufacturing potential. In stage 1, the production process is flexible and high cost, and becomes increasingly standardize, mechanized, and automated, resulting in an inflexible and cost-efficient process. A company can move between stages. Chase and Hayes (1991) expanded on the model to include service firms. Cruz and Rodriguez (2008) also used the theoretical framework to assess the effectiveness of the operations strategy.\nStage 1.\nThe company's approach to manufacturing is reactive, dealing with day-to-day problems like machine breakdowns, quality and delivery difficulties. They cannot use the potential of manufacturing as they struggle with foundation issues. The management will emphasize increasing equipment and technological investments rather than improving infrastructure like planning and measurement systems and workforce policies.\nStage 2.\nCompanies would have long-term goals to achieve industry standards. The focus will be on productivity enhancement and economies of scale meeting standard practice. Companies would favor capital investments as the means for gaining competitive advantages. Their main aim is competitive parity in the manufacturing process.\nStage 3.\nThe business strategy would generate the manufacturing strategy. Charter and mission statements are used to improve the company's competitive position by guiding manufacturing activities and decisions. Advancing manufacturing technologies like Computer-aided design (CAD), Computer-aided manufacturing (CAM) and Flexible manufacturing system (FMS), as well as practices like Just-in-time and lean manufacturing will be taken into consideration to enhance the product.\nStage 4.\nFirms will strategize to use manufacturing to boost their corporate competence. Their internal process and product improvements will advance past industry standards, eventually leading the sector. This will result in a sustainable competitive advantage. The manufacturing strategy will significantly motivate the competitive strategy and will influence major decisions of the company.\nProcess choices.\nProject.\nProjects is a process choice added by later writers. It refers to large-scale unique products. They are unique to the customer and are often too big to move, thus the project is the process of choice.\nJob shop.\nJob shops are semi-custom manufacturing processes with small-to-medium volume. Products are either unique to the order or have inconsistent demand with long gaps between orders. Because each output is different, efficiency is difficult. Each order requires varying structure, materials, form and possibly processing in accordance with the customer's design and specification, resulting in a jumbled flow with no repetitive pattern. This usually requires a process layout in which the machines are grouped in different areas of the shop according to purpose or function. This manufacturing process also requires highly skilled and experienced labor. Besides manufacturing operations like tools, machine and die manufacturers, it can also apply to service operations such as law offices, medical practices, automobile repair and tailor shops.\nBatch.\nBatch processes produce similar items on a repeated basis, often in higher volumes than job shops. Management might accumulate products so they can be processed together. The larger volume and repetition of requirements allows management to take a more effective manufacturing route as they optimize capacity and significantly reduce costs. There is a disconnected line flow or intermittent flow since the work-in-process move about different machine grouping in the shop in a jumbled fashion. It is smoother than job shop processing because the volume is higher and similarity in items allows the manufacturer to take advantage of the repetition. Printing and machine shops that have contracts for higher volumes of products are examples of the batch process in manufacturing. Examples of service operations could include some offices, some operations in hospitals, university and school classes and food preparations.\nLine.\nWhere the product has a consistent demand and large enough, the business can employ process referred to as mass-production such as the assembly line and continuous manufacturing. In the assembly line process, operations do not change with a standard and uninterrupted flow with a homogeneous output. This process is heavily automated with special-purpose equipment. Unlike the previous process, there is no variation in production. Managers would have a larger span of control and less skilled workers are needed because the standardization of the product means individual units do not have to me as closely monitored and controlled, easing routing, scheduling and control. The assembly line process also means machinery is organized according to sequence and is usually connected by an automated conveyor system, thus as a connected line flow. This is called a product layout. The set of inputs and outputs are often fixed and consistent with a continuous flow of work. An example of assembly-line manufacturing is automobile manufacturing. Car washes, class registration in universities and many fast food operations are services that employ assembly lines.\nContinuous.\nContinuous production involves raw materials undergoing successive operations such as refining and processing to a narrow range of extremely standardized products characterize as commodities in very high volumes. Continuous manufacturing requires substantial capital investment, so demand for the product must be exceptionally high. The cost of starting or stopping the process can be detrimental to the business. Thus, the processes often run non-stop with minimum downtime. High production levels also minimize the average fixed cost per unit. The process is self-monitoring with a fixed and automated route, which limits labor requirements to monitoring and maintaining the machinery. Industries that use this process include, gas, chemicals, electricity ores, rubber, petroleum, cement, paper, wood, and certain foods like milk, water, wheat, flour, sugar and spirits.\nAdvantages.\nThe matrix facilitates broader thinking about organizational competence and competitive advantage by including stages of the product lifecycle and its choice of the production process(es) for different products into its strategic planning process. It allows manufacturing managers to be more involved in the planning process so that their decisions can more effectively coincide with those of marketing and of the corporation itself. All resulting in more informed predictions about the changes in the industry with appropriate strategic responses.\nIn addition, the matrix can be used to identify business opportunities available given the company's manufacturing capabilities. It can aid in major decision-making about changes in the production process and guide investment decisions to stay in line with product and process plans. It helps to choose the best process and product structure when entering a new market and the suitable manufacturing facilities. It also helps identify and monitor the progress of important manufacturing objectives at a corporate level.\nDisadvantages.\nThe matrix does not account for the combinations of the product lifecycle and process lifecycle that do not follow the above-mentioned characteristics. \"Some 60 per cent of the firms studied did not fall on the diagonal\". Evolving management styles and technology are diminishing some of the inherent trade-offs found on the matrix, resulting in low predictive validity. Ahmad and Schroeder, however, suggest developing the matrix to include three axes rather than two. Besides the x-axis (product lifecycle stages) and the y-axis (Process lifecycle stages), they propose to add a z-axis to represent the company's inclusion of innovative initiatives.\nThe product variety considered in the matrix is also limited. Koth and Orne (1989) propose the complexity of products and organizational characteristics like the extent of vertical integration, size and geographical scope of the operations should affect the appropriate process design. Das and Narasimhan (2001) suggest advanced manufacturing technology for modular product structures can influence the contingency effect of the product variety and increase output and improve capabilities for job and batch shops in areas that were conventionally related with assembly lines and flow lines.\nThe matrix is static and its dimensions are too simple. The matrix is based on the current products but does not account for the dynamic nature of the firms’ operating environments. Processes should be designed with the evolution of product offerings and projected future product offerings in mind.", "Engineering,_Manufacturing": 1.0000040531, "qwen": "Yes"}
{"id": "58835926", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=58835926", "title": "Novosibirsk Chocolate Factory", "text": "Novosibirsk Chocolate Factory is a factory in Oktyabrsky District of Novosibirsk. It was founded in 1942. The factory is part of the United Confectioners Holding.\nHistory.\nThe factory was created on the basis of evacuated department of Odessa Confectionery Factory in 1942.\nProducts.\nThe Factory produces chocolate, marmalade, zefir (more than 80 kinds of products).", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1139553", "revid": "15675700", "url": "https://en.wikipedia.org/wiki?curid=1139553", "title": "Stud welding", "text": "Stud welding is a technique similar to flash welding where a fastener or specially formed nut is welded onto another metal part, typically a base metal or substrate. The fastener can take different forms, but typically fall under threaded, unthreaded, or tapped. The bolts may be automatically fed into the stud welder. Weld nuts generally have a flange with small nubs that melt to form the weld. \"Weld studs\" are used in stud welding systems. Manufacturers create weld studs for the two main forms of stud welding: capacitor discharge stud welding and drawn arc stud welding\nDrawn arc stud welding.\nDrawn arc stud welding joins a stud and another piece of metal together by heating both parts with an arc. The stud is usually joined to a flat plate by using the stud as one of the electrodes. The polarity used in stud welding depends on the type of metal being used. Welding aluminium, for example, would usually require direct-current electrode positive (DCEP). Welding steel would require direct-current electrode negative (DCEN).\nStud welding uses a flux tip and a ferrule, a ceramic ring which concentrates the heat, prevents oxidation and retains the molten metal in the weld zone. The ferrule is broken off of the fastener after the weld is completed. This lack of marring on the side opposite the fastener is what differentiates stud welding from other fastening processes.\nDrawn arc welding studs.\nDrawn arc studs range from a #8 to 1\" diameter. The lengths are variable from 3/8\" to 60\" (for deformed bars). Arc studs are typically loaded with an aluminium flux ball on the weld end which aids in the welding process. Drawn arc weld studs are commonly made from mild steel and stainless steel.\nShort cycle stud welding.\nShort cycle stud welding is a faster form of drawn arc stud welding which can use capacitor discharge weld studs instead of drawn arc studs. This method can tolerate welding studs to thinner sheet metals than the drawn arc process, though it does not achieve welds that are as strong or penetrative. It also does not require the use of ceramic ferrules. Sometimes operators using this process use shrouding gas to reduce spatter.\nCapacitor discharge stud welding.\nCapacitor discharge stud welding differs from drawn arc stud welding, in that capacitor discharge welding does not require flux. The weld time is shorter, enabling the weld to bond with little oxidation and no need for heat concentration. It also allows for small-diameter studs to be welded to thin, lightweight materials. This process uses a direct-current arc from a capacitor. The weld time in this process is between 1 and 6 milliseconds. Capacitor discharge stud welding with the latest equipment can create a weld without burn-through showing on the opposite side of very thin metals. CD stud welding is often used for smaller diameter studs and pins, as well as on non-standard materials and for accuracy. Drawn arc stud welding is primarily used for structural purposes and larger diameter weld studs.\nCapacitor discharge weld studs.\nCapacitor discharge weld studs range from 14 gauge to 3/8\" diameter. They come in many different lengths, ranging from 1/4\" to 5\" and larger. They are usually manufactured from mild or stainless steel, brass, aluminium, and aluminium alloy. The tip on the weld end of the stud serves a twofold purpose:\nWhen the tip disintegrates, it melts and helps solidify the weld to the base material.\nAutomated and robotic stud welding.\nPortable stud welding machines are available. Welders can also be automated, with controls for arcing and applying pressure. CNC stud welding machines can increase the speed and accuracy of manufacturing and construction work. Stud welding is versatile; typical applications include automobile bodies, electrical panels, shipbuilding and building construction. Shipbuilding is one of the oldest uses of stud welding, and the process revolutionized the shipbuilding industry. Other manufacturing industries can also use stud welding for a variety of purposes, from electrical and mechanical to decorative and consumer products.\nStandards.\nAmong the standards quoted in the list of welding codes, the following apply:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "505782", "revid": "5113002", "url": "https://en.wikipedia.org/wiki?curid=505782", "title": "Batch production", "text": "Batch production is a method of manufacturing where the products are made as specified groups or amounts, within a time frame. A batch can go through a series of steps in a large manufacturing process to make the final desired product. Batch production is used for many types of manufacturing that may need smaller amounts of production at a time to ensure specific quality standards or changes in the process. This is opposed to large mass production or continuous production methods where the product or process does not need to be checked or changed as frequently or periodically.\nCharacteristics.\nIn the manufacturing batch production process, the machines are in chronological order directly related to the manufacturing process. The batch production method is also used so any temporary changes or modifications can be made to the product if necessary during the manufacturing process. For example, if a product needed a sudden change in material or details changed, it can be done in between batches. As opposed to assembly production or mass production where such changes cannot be easily made. The time between batches is called cycle time. Each batch may be assigned a lot number.\nAdvantages.\nBecause batch production involves small batches, it is good for quality control. For example, if there is a mistake in the process, it can be fixed without as much loss compared to mass production. This can also save money by taking less risk for newer plans and products etc. As a result, this allows batch manufacturing to be changed or modified depending on company needs. In certain cases, batch production may require less expensive equipment, thus reducing the capital cost required to set up this type of system.\nDisadvantages.\nThere can be downtime between individual batches. Or if the product is constantly changing or being modified throughout the process, this also can cost downtime. Other disadvantages are that smaller batches need more planning, scheduling and control over the process and collecting data. Because of these factors, items made using batch production may have higher unit cost and take more time compared to continuous production.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "31590126", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=31590126", "title": "MEMS magnetic actuator", "text": "A MEMS magnetic actuator is a device that uses the microelectromechanical systems (MEMS) to convert an electric current into a mechanical output by employing the well-known Lorentz Force Equation or the theory of Magnetism.\nOverview of MEMS.\nMicro-Electro-Mechanical System (MEMS) technology is a process technology in which mechanical and electro-mechanical devices or structures are constructed using special micro-fabrication techniques. These techniques include: bulk micro-machining, surface micro-machining, LIGA, wafer bonding, etc.\nA device is considered to be a MEMS device if it satisfies the following:\nFor the analysis of every MEMS device, the Lumped assumption is made: that if the size of the device is far less than the characteristic length scale of the phenomenon (wave or diffusion), then there would be no spatial variations across the entire device. Modelling becomes easy under this assumption.\nOperations in MEMS.\nThe three major operations in MEMS are:\nThese three operations require some form of transduction schemes, the most popular ones being: piezoelectric, electrostatic, piezoresistive, electrodynamic, magnetic and magnetostrictive. The MEMS magnetic actuators use the last three schemes for their operation.\nMagnetic actuation.\nThe principle of magnetic actuation is based on the Lorentz Force Equation. \nWhen a current-carrying conductor is placed in a static magnetic field, the field produced around the conductor interacts with the static field to produce a force. This force can be used to cause the displacement of a mechanical structure.\nGoverning equations and parameters.\nA typical MEMS actuator is shown on the right. For a single turn of circular coil, the equations that govern its operation are:\nThe deflection of a mechanical structure for actuation depends on certain parameters of the device. For actuation, there has to be an applied force and a restoring force. The applied force is the force represented by the equation above, while the restoring force is fixed by the spring constant of the moving structure.\nThe applied force depends on both the field from the coils and the magnet. The remanence value of the magnet, its volume and position from the coils all contribute to its effect on the applied Force. Whereas the number of turns of coil, its size (radius) and the amount of current passing through it determines its effect on the Applied Force. The spring constant depends on the Young's Modulus of the moving structure, and its length, width and thickness.\nMagnetostrictive actuators.\nMagnetic actuation is not limited to the use of Lorentz force to cause a mechanical displacement. Magnetostrictive actuators can also use the theory of magnetism to bring about displacement. Materials that change their shapes when exposed to magnetic fields can now be used to drive high-reliability linear motors and actuators.. An example is a nickel rod that tends to deform when it is placed in an external magnetic field. Another example is wrapping a series of electromagnetic induction coils around a metal tube in which a Terfenol-D material is placed. The coils generate a moving magnetic field that courses wavelike down the successive windings along the stator tube. As the traveling magnetic field causes each succeeding cross section of Terfenol-D to elongate, then contract when the field is removed, the rod will actually \"crawl\" down the stator tube like an inchworm. Repeated propagating waves of magnetic flux will translate the rod down the tube's length, producing a useful stroke and force output. The amount of motion generated by the material is proportional to the magnetic field provided by the coil system, which is a function of the electric current. This type of motive device, which features a single moving part, is called an elastic-wave or peristaltic linear motor. (view:\nVideo of a Magnetostrictive micro walker)\nMagnet material.\nThe operation of the magnetic actuator depends on the interaction between the field from an electromagnet and a static field. To produce this static field, it is important to use the right material. In MEMS, permanent magnets have become the favorite because they have a very good scaling factor and they retain their magnetization even when there is no external field... meaning that they need not be continuously magnetized when they are in use\nIntegrating the magnet into the MEMS device.\nAs earlier discussed, MEMS devices are designed and fabricated using special micro-fabrication techniques. The major challenge however for magnetic MEMS is the integration of the magnet into the MEMS device. Recent research has suggested solutions to this challenge.\nFabrication (or molding) of the magnet.\nThere are several ways by which the magnet could be fabricated on a MEMS structure:\nIssues with magnetic actuation.\nEach of these challenges can be mitigated or lessened by the right choice of material, choice of molding or fabrication method, and the type of device that is to be constructed.\nApplications of the magnetic actuator include: the synthetic jet actuator, micro-pumps and micro-relays.", "Engineering,_Manufacturing": 1.0000076294, "qwen": "Yes"}
{"id": "7093932", "revid": "7770027", "url": "https://en.wikipedia.org/wiki?curid=7093932", "title": "Postponement", "text": "Postponement is a business strategy employed in manufacturing and supply chain management which maximizes possible benefit and minimizes risk by delaying further investment into a product or service until the last possible moment, or where a manufacturer produces a generic product, which can be modified at a later stage before the final distribution to the customer. An example of such a strategy is Dell Computers' build-to-order online store. One of the earliest references to the concept was in a paper by Walter Zinn and Donald J. Bowersox in the \"Journal of Business Logistics\" in 1988, which highlighted five types: labelling, packaging, assembly, manufacturing and time postponements.\nOne of the most modern definitions today is the following, suggested by Christopher (2005):\nA successful example of postponement – delayed differentiation – is the use of \"vanilla boxes\". Semi-finished computers are stored in advance of seeing the actual demand for the finished products. Upon seeing the demand, thus with no residual uncertainty – these “vanilla boxes” are finished by adding (or removing) components. The three key interrelated decisions are: (a) how many different types of vanilla boxes to stock, (b) in what quantities, and (c) how to finish to meet the order most effectively. Another example is an umbrella manufacturer who does not know what the demand will be for different colored umbrellas. The manufacturer will manufacture all white umbrellas and dye them later when umbrellas are in season and it is easier to predict demand of each color of umbrella. This way the manufacturer can stock up on white umbrellas early with minimal labor costs, and be sure of the demand before they dedicate time and money into predicting the demand so far in the future.\nHistorical development of postponement.\nAccording to various logistics journals, supply chain management books and articles, the postponement concept has three key dates in its development in the 20th century – 1950, 1965 and 1988:\nAfter the development of the concept in the 20th century, researchers started defining postponement differently since 2000 and there are two key developments in 2001 and 2004. In 2001, Remko Van Hoek pointed out that it is important to analyze postponement not just on the marketing and distribution channel levels but also on the supply chain level. He argued that previous theories developed in the 20th century had gaps in their research on postponement, and identified 5 challenges: 1. Postponement as a supply chain concept, 2. Integrating related supply chain concepts, 3. Postponement in the globalizing supply chain, 4. Postponement in the customized supply chain, 5. Methodological upgrading of postponement.\nIn the first challenge, Van Hoek criticised Bucklin’s and Zinn’s postponement theories as lacking application throughout the whole supply chain, since they only linked their theories to one of its levels (upstream – sourcing & components, midstream - manufacturing, downstream - distribution). Professor Van Hoek states that “specific study should be undertaken to assess what extent postponement is applied at various positions in the supply chain”.\nThe second challenge states that to cover the entire supply chain in conceptualization of postponement, a researcher would need to engage related concepts, e.g. just-in-time manufacturing and supply, efficient consumer response.\nGlobalization in postponement comes as the third challenge. He states that there are differences in language, culture across the world and that postponement is widely present in Western countries rather than emerging countries in Asia. Therefore, Van Hoek advises to analyse these geographical dimensions when conducting a research on postponement.\nThe fourth challenge discusses lack of typology in postponement. Researches should not only pay attention to manufacturing and logistics related postponement but also to service postponement, since the concept takes its place in services too.\nFinally, the fifth challenge tells that in order to conduct a solid research plan on postponement one should consider the triangulation model with first step – how postponement is implemented in a global supply chain, second step – where, to what extent and how postponement is applied, third step – benefits of postponement in the customized supply chain.\nIt should be stated that Van Hoek has made a solid contribution into postponement concept development as he provided these 5 challenges, and raised interest on postponement, i.e. there has been more literature on postponement available.\nYang \"et al.\" (2004) arranged the Zinn and Bowersox postponement strategies into more accurate groups and explained how exactly the strategy is matched to a type of postponement.\nYang \"et al.\" stated that in order to cope with high level of uncertainty, purchasing postponement (purchasing materials as close to production as possible) product development postponement may be applied => no physical inventory. In contrast, to deal with low uncertainty we use logistics postponement (reduction of obsolete inventories, just-in-time delivery) and production postponement => semi-finished product. With high modularity (when components can be incorporated into products with almost no change) product development and production postponements are used, whereas with low modularity (when customization is required) – logistics and purchasing postponements. This is what exactly was lacking in the 20th century because you did not know whether physical inventory, semi-finished, or finished products would work best as it was uncertain due to fluctuating consumer demands. Therefore, Yang \"et al.\" provides us with a guideline on how to manage this uncertainty.\nTerminology.\nThacker uses the term \"point(s) of mutation\" to refer to the potentially postponable stages in a production process when products become more specialised.", "Engineering,_Manufacturing": 0.9971225262, "qwen": "Yes"}
{"id": "7097296", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=7097296", "title": "DMSMS", "text": "Diminishing manufacturing sources and material shortages (DMSMS) or diminishing manufacturing sources (DMS) is defined as: \"The loss or impending loss of manufacturers of items or suppliers of items or raw materials.\" DMSMS and obsolescence are terms that are often used interchangeably. However, obsolescence refers to a lack of availability due to statutory or process changes and new designs, whereas DMSMS is a lack of sources or materials.\nImpact.\nAlthough it is not strictly limited to electronic systems, much of the effort regarding DMSMS deals with electronic components that have a relatively short lifetime.\nCauses.\nPrimary components.\nDMSMS is a multifaceted problem because there are at least three main components that need to be considered. First, a primary concern is the ongoing improvement in technology. As new products are designed, the technology that was used in their predecessors becomes outdated, making it more difficult to repair the equipment. Second, the mechanical parts may be harder to acquire because fewer are produced as the demand for these parts decreases. Third, the materials required to manufacture a piece of equipment may no longer be readily available.\nProduct life cycle.\nIt is widely accepted that all electronic devices are subject to the product life cycle. As products evolve into updated versions, they require parts and technology distinct from their predecessors. However, the earlier versions of the product often still need to be maintained throughout their life cycle. As the new product becomes predominant, there are fewer parts available to fix the earlier versions and the technology becomes outdated.\nAccording to EIA-724 there are 6 distinct phases of a product's life cycle: Introduction, Growth, Maturity, Saturation, Decline, and Phase-Out. To the uninitiated these terms often seem abstract and odd. These terms are often used in databases covering parts life cycle so it is important to have an understanding of what they mean. Although the terms \"Introduction\", \"Growth\", and \"Decline\" are generally accepted without much explanation, the terms \"Maturity\", \"Saturation\", and \"Phase-Out\" are less obvious.\n\"Maturity\" in this case refers to state in the product's life cycle where sales of the product \"first\" reach its sales peak and begins to level off. Having survived the Introduction and Growth phases, products in this phase have a low probability of being discontinued.\n\"Saturation\" refers to a state in the product's life cycle where sales have leveled off and, towards the end of this phase, first begin to decline. The term \"Saturation\" is confusing to many and can be explained in reference to its equivalent in chemistry where a substance can no longer be dissolved in a liquid. A product can be said to have \"saturated\" its market. The decline at the end of the Saturation phase gives the first indications of the products end of life.\n\"Phase-out\" refers to the final stages of a product's decline ending in the product being altogether discontinued by the supplier.\nMitigation.\nDMSMS is managed through various risk mitigation efforts, both during the manufacturing of a product as well as later in the products life cycle. DMSMS is a hot topic in military supply where the usable lifetime of an electronic system may far exceed the availability of the components used to produce that system.\nDevices in phases 5 and 6 of a product's life cycle require caution on the part of designers and product support engineers to assure that system components are indeed available at the time of production.\nSome examples of the signs and symptoms of a DMSMS issue are:\nThe core methodology for DMSMS analysis has been to make direct contact with the supplier of an item. Direct contact takes the form of phone, e-mail or other communication with a competent supplier representative. This is essential in the management of commercial off-the-shelf products and assemblies. The main items of concern in a DMSMS analysis are:\nMonitoring.\nOther methodologies involve subscription to data services which monitor parts lists, known as a Bill of Materials (BOM), for activity on any one part in the user's list. Often both the classic methodology and the data subscription methodology will be used in conjunction to provide a more complete assessment of a part's availability and lifetime.\nLifetime buy.\nOne strategy used to combat DMS is to buy additional inventory during the production run of a system or part, in quantities sufficient to cover the expected number of failures. This strategy is known as a lifetime buy. An example of this is the many 30- and 40-year-old railway locomotives being run by small operators in the United Kingdom. These operators will often buy more locomotives than they actually require, and keep a number of them stored as a source of spare parts.\nTake action.\nIt is important and responsible to use a DMSMS risk management plan to ensure parts are available when you need them. Long range planning must occur for every key piece of equipment, establishing \"when\" and \"what\" parts will be replaced or redesigned. Try to foresee potential equipment problems. Consider replacing obsolete parts and equipment. New methods of design engineering allow for the open exchange of parts as technology changes. There are also companies out there giving assistance and consult in seminars and workshops, audits and implementation of effective DMSMS processes.", "Engineering,_Manufacturing": 0.9998376369, "qwen": "Yes"}
{"id": "7102590", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=7102590", "title": "Zygo Corporation", "text": "Zygo Corporation, or simply Zygo, is a manufacturer headquartered at Middlefield, Connecticut that specializes in optical systems and equipment. Their metrology product lines include 3D measuring microscopes using coherence scanning interferometry, laser Fizeau interferometers for testing optical components, laser displacement interferometers, and heterodyne optical encoders for stage position metrology. Zygo’s optics business manufactures both optical assembly and custom optics for medical instruments and national labs. Over 750 patents have been awarded since the Company's founding.\nIn October 2008, competitor ESI attempted to acquire Zygo for approximately 174 million USD worth of stock but the buy-out was stymied by Zygo's board of directors. Zygo later became part of the Ultra Precision Technologies Division of Ametek, Inc. as a result of a 2014 acquisition.\nHistory and products.\nThe company was founded in 1970 by Paul Forman, Carl Zanoni, and Sol Laufer, with financial support from Canon Inc. and Wesleyan University. An initial priority for the Company was to build a world-class optical fabrication facility for producing optics with the highest precision plano surfaces and angles.\nIt was recognized that in order to achieve such a goal, practical and easy-to-use interferometry would have to be a standard part of the fabrication process. While there were several interferometers available on the market at that time, none had all the flexibility or features needed for Zygo’s facilities and were also extremely cost-prohibitive. An interferometer was developed in 1974 for these in-house purposes, the Model GH, and it later became Zygo’s first commercial product with a second model, the Mark II, being its breakout success.\nIn the 1990s, Zygo expanded its offerings to include software designed for lower cost personal computers and brought to market its ZMI metrology lasers.\nAwards and accolades.\nTwo researchers working received the Rudolf Kinglake Medal for their work while employed at Zygo in optical engineering in 2016. \nIn 2000, Zygo successfully sued Wyko Corp for patent infringement of a breadboard-based interferometer first registered by Zygo in 1978.", "Engineering,_Manufacturing": 0.9795390368, "qwen": "Yes"}
{"id": "8847552", "revid": "5662528", "url": "https://en.wikipedia.org/wiki?curid=8847552", "title": "Aras Corp", "text": "Aras Corporation is an American developer and publisher of product development software, Aras Innovator. The product is used for product lifecycle management (PLM) and other purposes. Since 2007, Aras has been providing Aras Innovator for free as \"Enterprise open-source software\", with Aras Corp providing technical support, software updates, and other consulting as a subscription service. Aras Corp was founded in 2000 in Andover, Massachusetts by Peter Schroer.\nAras Innovator is an enterprise software suite for managing product lifecycle management business processes. The product is based on the Microsoft .NET Framework and SQL Server. The product is used for product lifecycle management (PLM), advanced product quality planning (APQP), lean product development, product quality control, collaborative product development and new product introduction (NPI).\nUntil 2007, Aras sold their product as proprietary software for enterprises.\nIn 2007, Aras began providing Aras Innovator as open-source software. Clients obtain the software for free, and Aras Corp provides technical support, software updates, and other consulting as a subscription service.\nIn July 2020, Aras confirmed the introduction of a new framework, Digital Twin Core, which introduces functionality for generating and handling digital twins to the Aras low-code package. Aras Cloud PLM provides a secure, cost-effective, and scalable solution for customers who need to manage their product data in the cloud.", "Engineering,_Manufacturing": 0.9978412986, "qwen": "Yes"}
{"id": "13004865", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=13004865", "title": "Profile angle", "text": "The profile angle of a gear is the angle at a specified pitch point between a line tangent to a tooth surface and the line normal to the pitch surface (which is a radial line of a pitch circle). This definition is applicable to every type of gear for which a pitch surface can be defined. The profile angle gives the direction of the tangent to a tooth profile.\nIn spur gears and straight bevel gears, tooth profiles are considered only in a transverse plane, and the general terms profile angle and pressure angle are customarily used rather than transverse profile angle and transverse pressure angle. In helical teeth, the profiles may be considered in different planes, and in specifications it is essential to use terms that indicate the direction of the plane in which the profile angle or the pressure angle lies, such as transverse profile angle, normal pressure angle, axial profile angle.\nTypes.\nStandard.\nIn tools for cutting, grinding, and gaging gear teeth, the profile angle is the angle between a cutting edge or a cutting surface, and some principal direction such as that of a shank, an axis, or a plane of rotation.\nStandard profile angles are established in connection with standard proportions of gear teeth and standard gear cutting tools. Involute gears operate together correctly after a change of center distance, and gears designed for a different center distance can be generated correctly by standard tools. A change of center distance is accomplished by changes in operating values for pitch diameter, circular pitch, diametral pitch, pressure angle, and tooth thicknesses or backlash. The same involute gear may be used under conditions that change its operating pitch diameter and pressure angle. Unless there is a good reason for doing otherwise, it is practical to consider that the pitch and the profile angle of a single gear correspond to the pitch and the profile angle of the hob or cutter used to generate its teeth.\nTransverse.\nThe transverse pressure angle and transverse profile angle are the pressure angle and the profile angle in a transverse plane.\nNormal.\nNormal pressure angle and normal profile angle are the pressure and profile angles in a normal plane of a helical or a spiral tooth. In a spiral bevel gear, unless otherwise specified, profile angle means normal profile angle at the mean cone distance.\nAxial.\nAxial pressure angle and axial profile angle are the pressure angle and the profile angle in an axial plane of a helical gear or a worm, or of a spiral bevel gear.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "36960047", "revid": "42522270", "url": "https://en.wikipedia.org/wiki?curid=36960047", "title": "Thin-wall injection molding", "text": "Thin wall injection molding is a specialized form of conventional injection molding that focuses on mass-producing plastic parts that are thin and light so that material cost savings can be made and cycle times can be as short as possible. Shorter cycle times means higher productivity and lower costs per part.\nThe definition of thin wall is really about the size of the part compared to its wall thickness. For any particular plastic part, as the wall thickness reduces the harder it is to manufacture using the injection molding process. The size of a part puts a limit on how thin the wall thickness can be. For packaging containers thin wall means wall thicknesses that are less than 0.025 inch (0.62mm) with a flow length to wall thickness greater than 200.\nMarkets.\nThe trend towards thin wall molding continues to increase in many plastic industries as plastic material and energy costs continue to rise and delivery lead times are squeezed.\nThe following industries make use of thin wall molding: \nExamples.\nPlastic resins suitable for thin-wall molding should have high-flow properties, particularly low melt viscosity. In addition, they need to be robust enough to avoid degradation from the heat generated by high shear rates (high injection speeds)\nSome plastic manufacturers make plastics specifically for thin wall applications that have excellent flow properties inside the mold cavity. For example, plastic manufacturer Sabic has a polypropylene food contact grade plastic which is specifically designed for thin wall margarine containers and lids.\nAnother plastic manufacturer, Bayer, makes a blend of Polycarbonate (PC) and Acrylonitrile butadiene styrene (ABS) specifically designed to make thin wall mobile housings.\nEquipment.\nPlastic injection molding machine.\nCompared to conventional injection molding, thin wall molding requires molding machines that are designed and built to withstand higher stresses and injection pressures. The molding machines computer control should also be precise in order to make quality parts. For this reason these molding machines are more expensive than general purpose machines. \nThin-wall-capable machines usually also have accumulator-assisted clamps to accommodate fast cycle times.\nRegular maintenance schedules must be completed so that the machine and part quality does not suffer. These machines usually work 24/7 so they need to be well maintained.\nInjection mold design.\nAs with the injection molding machines, injection molds need to be robust enough to withstand high stresses and pressures. Heavy mold construction with through hardened tool steels will ensure a long lasting mold.\nThe mold must also have a well designed cooling system so that heat can be quickly extracted from the hot plastic part allowing fast cycle times. To achieve this, cooling channels need to be designed close to the molding surface. \nCleaning the mould on a daily basis is also a critical requirement to maintain the part quality.\nRobotics.\nIn countries where manual labour is expensive, robots are commonly used to remove the plastic parts from the mold and order them into equal stacks. These robots are fixed to the molding machine and need to be fast and reliable.\nPlastic injection molding process.\nThe range of process parameters, which are employed for thin wall molded parts, is considerably narrower than that of conventional injection molding because thin parts are difficult for the injection unit of the machine to fill compared to thicker parts. Even with optimally designed parts and molds, it is still more difficult to produce parts with thin walls.\nConsistent injection speeds and pressures are required to maintain the quality of the parts produced from thin wall molding. A properly trained molding technician who understands and operates the machine within the confines of the narrow processing window at which the molded product's production cost-effectiveness is optimized will ensure that the process produces quality parts during the production.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "15759109", "revid": "43553972", "url": "https://en.wikipedia.org/wiki?curid=15759109", "title": "Parallels (engineering)", "text": "Parallels are rectangular blocks of metal, commonly made from tool steel, stainless steel or cast iron, which have 2, 4 or 6 faces ground or lapped to a precise surface finish. They are used when machining with a mill, drill or any other machining operation that requires work to be held in a vise or with clamps - to keep work parallel or raised evenly such as in a milling vise to give adequate height for the cutting tool/spindle to pass over.\nDescription.\nParallels come in pairs of two, which are machined to be the same dimensions as their corresponding faces. They come in a variety of thicknesses and size, allowing them to be stacked up or to support a workpiece which doesn't have a flat profile. Parallels commonly have a series of holes drilled on the 'front' face - allowing them to be used to position a workpiece or secured using t-slot clamps, and a countersink on each side to remove any sharp edges. \nGenerally, workshop parallels have 4 faces that are machined and ground - the front, back and sides, although some do have the ends with a smooth surface. The surface of a parallel can often tell how it was manufactured, with a 'grain' showing that it was ground - and a smooth or mirrored finish showing it has been lapped. Parallels that have a good surface tolerance can be lightly bonded together by sliding or rotating two parallels together, and the smooth surfaces allows a temporary molecular-attraction to take place - this is known as Wringing and is also found with gauge blocks.\nManufacturing.\nThere are two main grades of surface tolerance:\nParallels are first machined to rough dimensions, leaving a few millimeters to allow the rest to be ground. Parallels that only have 2 or 4 precision faces will often have the tool-marks from the machining on the non-ground sides. They are then paired and placed in a grinding machine, and each face is ground until the overall dimensions are correct - they are paired during this stage so that even if the dimensions are not correct, they are still parallel to each other. Then, the individual finishes are applied, from drilling to machining a chamfer along the edges to remove any burrs or sharpened edges. They may also be lapped to achieve a mirror smooth surface. Most parallels are also hardened.\nParallels are manufactured to either imperial or metric dimensions, and are often sold in a set, with several pairs of different sizes.\nUses.\nParallels are used in machining operations, be it milling, drilling, turning or sometimes grinding. The most common use is to support work when it is in a vise or clamped to the machine bed. If a workpiece is too small to be machined in a vise without it being in contact with all three faces of the vice - parallels can be used either side to give clearance from the vise, and to give support from underneath to eliminate the workpiece being pushed down by the force of the cutting tool.\nParallels of different sizes can be used to support a workpiece that doesn't have a 'flat' surface underneath, or to give clearance when drilling in a vise to stop the drill damaging the vise. Parallels can also be used if the vise itself has a damaged face, which could cause the workpiece to be held insecurely. \nOther uses include giving a raised surface when using t-slot clamps and for comparison with a surface or machined face to check the flatness.", "Engineering,_Manufacturing": 0.999961257, "qwen": "Yes"}
{"id": "30892032", "revid": "1456683", "url": "https://en.wikipedia.org/wiki?curid=30892032", "title": "Graping", "text": "Graping is a phenomenon marked by the appearance of unreflowed solder particles on top of the solder mass. The solder that is partially coalesced looks like a cluster of grapes which is where the phenomenon’s name is derived.\nCauses.\nGraping occurrence has continued to increase since it was first identified in 2006. The viscosity of the flux decreases as the temperature of the reflow oven increases. Lead-free reflow soldering temperatures are higher which results in more graping. Graping is also caused by increased surface oxidation. The increased surface oxidation is the result of smaller printed paste deposit volumes that cause a diminished surface area to flux ratio of the solder particle resulting in flux exhaustion. While solder paste can be manufactured using any size range, there has been a move towards finer particle sizes, especially for fine feature stencil printing. Finer particle sizes places added pressure on the solder paste flux to remove surface oxides which leaves the outside of the joint not fully coalesced producing the irregular surface finish known as graping.\nResolutions.\nThe graping phenomenon can be resolved utilizing proper solder materials in addition to correct reflow profile settings. Solder powders are available that provide a tighter distribution range as well as a high oxidation barrier. This barrier not only improves the paste release from the stencil, but also provides an ideal surface area-to-volume ratio. These solder powder characteristics help to eliminate the graping phenomenon. Future solder paste flux formulations provide sufficient activity paired with re-oxidation mitigation capabilities. This pairing means that graping can be resolved as it occurs which is ideal for miniaturization processes.\nThere are also steps to take when setting up your reflow profile to reduce the amount of heat exposure to the solder paste during the reflow process and prevent graping. ", "Engineering,_Manufacturing": 1.0000083447, "qwen": "Yes"}
{"id": "49289621", "revid": "11308236", "url": "https://en.wikipedia.org/wiki?curid=49289621", "title": "Annealed pyrolytic graphite", "text": "Annealed Pyrolytic Graphite (APG), also known as Thermally Annealed Pyrolytic Graphite (TPG), is a form of synthetic graphite that offers excellent in-plane thermal conductivity. As with pyrolytic carbon or pyrolytic graphite (PG), APG is also low in mass, is electrically conductive, and offers diamagnetic properties that allow it to levitate in magnetic fields.\nPhysical Properties.\nAPG is an anisotropic material with extremely high in-plane thermal conductivity (1,700 W/m-K at room temperature ) and low through-thickness conductivity. Its laminate structure remains stable across a wide temperature range allowing it to be used in a variety of heat transfer applications. APG's conductivity generally increases as the temperature decreases, peaking at 2,800 W/m-K at approximately 150 K. Unlike pyrolytic graphite, the x-y planar conductivity is consistent across each basal plane, thus the conductivity in the center planes is consistent with the outer planes. The in-plane covalently bonded carbon atoms in a hexagonal geometry account for APG's high in-plane thermal conductivity and its high in-plane stiffness. Through its thickness, these hexagonal planes are weakly bonded (van der Waals bonds) resulting in a material with poor through-thickness thermal conductivity, stiffness, and strength.\nSynthesis.\nAPG is produced in a process similar method to Highly Oriented Pyrolytic Graphite (HOPG), where hydrocarbon gas is heated until it breaks down into carbon. Pyrolytic graphite (PG) is then grown on plates using a chemical vapor deposition (CVD) process. The PG is then annealed at high temperature to form the more planar and more uniform carbon structure of APG, described above. The primary difference between the HOPG and APG synthesis methods is that the APG annealing process does not require the use of induced stresses, resulting in a more affordable and practical bulk material for production use.\nApplications.\nAPG is primarily used as a heat spreader for the thermal management of high-end electronics. Due to its poor mechanical properties APG is typically encapsulated within in structural metallic materials. Aluminum is the most commonly chosen encapsulant for its strength, low mass, cost, manufacturability, and thermal conductivity. Since APG's conductivity is much lower through its thickness, thermal vias are sometimes inserted into the assembly to transfer heat into the graphite, as shown in Figure 1. These vias are typically composed of aluminum or copper. Thin, flexible sheets of APG can be encapsulated in thin flexible materials, such as polymers, aluminum foil, or copper foil to create what is known as a Thermal Strap.\nAerospace: Aluminum-APG plates are most commonly used as heat spreader plates to transfer heat away from high power density electronics in aircraft and spacecraft.\nScientific Cameras: Cu-APG plates are used to cool and isothermalize CCD detectors at cryogenic temperatures.", "Engineering,_Manufacturing": 0.9999986887, "qwen": "Yes"}
{"id": "49316948", "revid": "21309140", "url": "https://en.wikipedia.org/wiki?curid=49316948", "title": "Grinding wheel wear", "text": "Grinding wheel wear is an important measured factor of grinding in the manufacturing process of engineered parts and tools. Grinding involves the removal process of material and modifying the surface of a workpiece to some desired finish which might otherwise be unachievable through conventional machining processes. The grinding process itself has been compared to machining operations which employ multipoint cutting tools. The abrasive grains which make up the entire geometry of wheel act as independent small cutting tools. The quality, characteristics, and rate of grinding wheel wear can be affected by contributions of the characteristics of the material of the workpiece, the temperature increase of the workpiece, and the rate of wear of the grinding wheel itself. Moderate wear rate allows for more consistent material size. Maintaining stable grinding forces is preferred rather than high wheel wear rate which can decrease the effectiveness of material removal from the workpiece.\nMechanisms of wheel wear.\nA common attributing factor to wheel wear is grain fracture, which can be an advantage. A portion of each of the individual grains on the wheel surface breaks apart and leaves the remaining grain bonded to the wheel. The fractured grain is left with newly exposed sharp edges which attribute the self-sharpening characteristic of grinding wheels and cutting tools in general. Attritious wear or progressive wear which is typically undesirable leads to the grains dulling by developing flat spots and rounded edges on the wheel which can deteriorate the wheel’s ability to remove material. Flat spots also can lead to excessive heat generation with the added surface contact which in turn enables bond fracture, or the brittle fracture of the adhesive bonds between the grains. The removal of these worn grains from the adhesive bonds restores the wheel’s cutting ability once more. Grinding wheels can also be characterized by the grains’ increased capacity to fracture according to a level of higher value of friability. Different bonding materials are used depending on the intended use of the grinding wheel. The bonding material is classified by its individual strength called its wheel grade.\nGrinding forces.\nThe longevity and cutting ability of a grinding wheel can be affected by the grinding forces generated while in use. Experimental investigation has revealed a direct relationship between cutting speed, wheel geometry, chip geometry, and the grinding forces namely the resultant normal force component (\"Fn ),\" the tangential force component (\"Ft ),\" and their ratio when in contact with a workpiece.\nStage I: As a workpiece enters the grinding zone the initial contact forces are unstable and rise abruptly short period of time and a small wear spot is formed. The overall performance of a wheel during this moment of unstable rising forces can be minimized with proper dressing conditions prior to use and can help effect the high peak and steady state forces which should normally be contained within a short period of time.\nStage II: During the steady state wear stage reaction forces are constant and the flow of heat generation in both the work piece and wheel remain in equilibrium. The measurable data in this stage presents itself as a linear rate of wear as a function of the working duration of the dresser application or tool life (\"Td\"). The tool life corresponds to the grinding wheels ability to maintain the initial shape give to it during the dressing prior to use. As the workpiece stays full contact with the grinding zone in the steady state of constant forces the flow of heat generation in the work piece and the wheel maintains equilibrium. This phase usually does not produce temperatures that would coincide with bond fracture however the material properties of the bond strength can determine the maximum applied force the wheel grit can sustain prior to fracture.\nStage III: Wear rates on the workpiece become detrimental while the rate of change in reaction forces decreases. The end of tool-life represent the initial dressing condition are no longer effective. The rate of change of forces generated in this stage are minimal and wear on the workpiece as an exponential tendency.\nEffects of cutting temperature.\nThe lifespan of the grinding wheel and final surface properties of the workpiece are directly affected by the operating cutting temperature. Heat generated during grinding penetrates the grinding wheel and the workpiece which can cause dimensional errors due to thermal expansion \nSeveral adverse effects of a high cutting temperature are as follows: \nThe addition of grinding fluids can effectively control cutting temperatures to reduce heat induced surface effects on the wheel and workpiece.\nHigh heat flux density may result in the grinding wheel melting and consequently, increased wear. The heat flux (Φ) penetrating the grinding wheel and workpiece depends mainly on the cutting speed (vs) and cutting force (Fc). The temperature of the grinding wheel is related to the density of heat flux (φ = dΦ/dA) generated (which also is directly proportional to the feed rate). An approximate value of the heat flux can be calculated as follows: Φ = Fc • vs\nGrinding wheel types.\nGrinding wheels can be made with a variety of materials depending on the desired abrasive quality required during use. Abrasive material, natural of synthetic, used in grinding include some common types of grinding wheel geometry.\nAbrasive grains.\nThe process of grinding requires an abrasive component with material properties harder than the workpiece. Most common grinders employ a rotating surface being brought in contact with a work surface. The wheel component of grinder itself is generally composed of abrasive grains held together by a bond structure which contain some amount of porosity.\nWheel speed.\nThe grinding wheel typically operates at high rotational speeds. The wheel speed depends on several factors, some of which included the grindability of the wheel, the shape of the part, and the material of the workpiece. These properties will affect important parameters such as the surface finish, surface integrity, and wheel wear. Likewise, the grinding wheel speed will depend on which abrasive process is needed and which finishing process is desired.\nDressing.\nA worn grinding wheel can be dressed to restore its grinding properties. Dressing a grinding wheel causes new grains to be produced on a glazed or loaded grinding wheel. A glazed grinding wheel is the result of high attritious wear causing the grains to become dull. A loaded grinding wheel is a result of chips clogging the grains on the grinding wheel due to the grinding of soft materials, improper grinding wheel selection processing parameters. In addition to sharpening a grinding wheel dressing can also be used to true a grinding wheel that is out of round or to shape the profile of a grinding wheel to produce specific features on the workpiece.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "861757", "revid": "42342156", "url": "https://en.wikipedia.org/wiki?curid=861757", "title": "IBM 1132", "text": "The IBM 1132 line printer was the normal printer for the IBM 1130 computer system. It printed 120 character lines at 80 lines per minute. The character set consisted of numbers, upper-case letters and some special characters.\nThe 1965-introduced 1132 was built around a stripped down IBM 407 printing mechanism. The 407 was IBM's top-of-the-line accounting machine from the 1950s. The 1130 had 120 power transistors, each wired to the print magnet for one printer column. The magnet released a lever that engaged a cam with a spinning clutch shaft. The engaged cam then made one revolution, pushing its print wheel toward the ribbon and paper, thereby printing one character. \nAs the set of 120 print wheels spun, the 1130 received an interrupt as each of the possible 48 characters was about to move into position. The printing driver software had to quickly output a 120 bit vector designating which transistors were to fire so as to drive the print wheel against the ribbon and paper. This put a big performance burden on the CPU, but resulted in an inexpensive (for the time) printer.\nSometimes a printer output line transistor would fail, resulting in a blank print position. If you knew your way around inside the 1130, it was possible to swap circuit cards so as to move the bad print position to near the right end of the printed line. This kept the 1130 usable until the repair person showed up.\nThe 1132 came in two models with the following characteristics:", "Engineering,_Manufacturing": 0.9986362457, "qwen": "Yes"}
{"id": "7233400", "revid": "1152268071", "url": "https://en.wikipedia.org/wiki?curid=7233400", "title": "WEA Manufacturing", "text": "WEA Manufacturing was the record, tape, and compact disc manufacturing arm of WEA International Inc. from 1978 to 2003, when it was sold and merged into Cinram International, a previous competitor. The last owner when the plant closed was Technicolor.\nHistory.\nWEA Manufacturing Inc. was created in 1978–1979 when Warner Communications Inc. purchased two of its longtime suppliers: the record pressing plants Specialty Records Corporation (Olyphant, Pennsylvania) and Allied Record Company (Los Angeles). The company was headquartered in Olyphant, where the original plant was replaced in late 1981 by a new facility which retained the name Specialty Records Corporation. The Specialty Records Corporation name was dropped in 1996 in favor of WEA Manufacturing.\nThe company invested in CD manufacturing in 1986, matching a $247,000 contribution by economic development corporation Ben Franklin Technology Partners to develop and implement new processes of manufacturing audio CDs and CD-ROMs. BFTP assembled a team of experts in physics, electrical engineering, and thin film technology from the University of Scranton and Lehigh University to carry out the research and development. The Olyphant plant and another plant in Alsdorf, Germany, were expanded to support CD pressing that year, with the Olyphant facility's production commencing first in September 1986.\nWEA Manufacturing grew to become one of the largest manufacturers of recorded media in the world.\nThe company began manufacturing Laserdiscs in July 1991.\nThe company's DVD division, Warner Advanced Media Operations (WAMO), helped design the high-density format used in DVDs, and manufactured some of the first DVDs in the late 1990s.\nThe company was sold to Cinram International in October 2003 and no longer exists under the name WEA Manufacturing, but the Olyphant plant continued to operate under its new ownership. In 2005, the company was Lackawanna County's largest employer, with over 2,300 people working at the Olyphant plant.\nCinram closed the former Allied plant in 2006, while Technicolor (which purchased Cinram's assets in 2015) closed the Olyphant plant in 2018.\nPatents.\nWEA Manufacturing held U.S. patents related to compact disc manufacture:\nLitigation.\nIn 1990, WEA Manufacturing was sued by a Canadian firm, Optical Recording Co. (ORC), for alleged infringement of two 1971 patents related to glass mastering equipment which was used by Time Warner and WEA Manufacturing in the manufacture of approximately 450 million CDs. ORC contended that unlike five other major CD manufacturers in the U.S., Time Warner had refused to license the technology from ORC. In 1992, a jury assessed damages of 6 cents per disc, plus $4–5 million in interest.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "17699823", "revid": "9895903", "url": "https://en.wikipedia.org/wiki?curid=17699823", "title": "Leather punch", "text": "A leather punch is a hole punch specifically for making holes in leather. The working tip of the punch is a hollow steel cylinder with a sharp circular knife-like edge. The leather piece is placed on a hard surface, which may be a part of the tool set, and the punch is forced through it, cutting out a small circular piece which is discarded. The punch may be a simple metal tool struck with a hammer; or several such punches may be mounted on a rotary turret on a pliers-like tool with an anvil, with the desired size selected by rotating the turret. Hole diameters typically range from about 1mm to 6mm. They are typically used for making holes for buckles, eyelets, and rivets in shoes, belts, bridles, etc.", "Engineering,_Manufacturing": 0.9960221052, "qwen": "Yes"}
{"id": "2564173", "revid": "21857263", "url": "https://en.wikipedia.org/wiki?curid=2564173", "title": "Contract manufacturer", "text": "A contract manufacturer (CM) is a manufacturer that contracts with a firm for components or products (in which case it is a turnkey supplier). It is a form of outsourcing. A contract manufacturer performing packaging operations is called copacker or a \"contract packager\". Brand name companies focus on product innovation, design and sales, while the manufacturing takes place in independent factories (the turnkey suppliers).\nMost turnkey suppliers specialize in simply manufacturing physical products, but some are also able to handle a significant part of the design and customization process if needed. Some turnkey suppliers specialize in one base component (ex. memory chips) or a base process (e.g. plastic molding).\nBusiness model.\nIn a contract manufacturing business model, the hiring firm approaches the contract manufacturer with a design or formula. The contract manufacturer will quote the parts based on processes, labor, tooling, and material costs. Typically a hiring firm will request quotes from multiple CMs. After the bidding process is complete, the hiring firm will select a source, and then, for the agreed-upon price, the CM acts as the hiring firm's factory, producing and shipping units of the design on behalf of the hiring firm.\nJob production is, in essence, manufacturing on a contract basis, and thus it forms a subset of the larger field of contract manufacturing. But the latter field also includes, in addition to jobbing, a higher level of outsourcing in which a product-line-owning company entrusts its entire production to a contractor, rather than just outsourcing parts of it.\nIndustries that use the practice.\nMany industries use this process, especially the aerospace, defense, computer, semiconductor, energy, medical, food manufacturing, personal care, packaging, and automotive fields. Some types of contract manufacturing include CNC machining, complex assembly, aluminum die casting, grinding, broaching, gears, and forging. The pharmaceutical industry uses this process with CMs called contract manufacturing organizations, constituting a $14 billion business segment around 2022. In the semiconductor industry, this practice is called the foundry model. Contract manufacturing is specially prevalent in the electronics industry.\nPurpose, benefits, and risks.\nThere are many benefits as well as risks to contract manufacturing. Companies are finding many reasons why they should outsource their production to other companies. However, production outside of the company has many risks attached. Companies must first identify their core competencies before deciding about contract manufacturers. A company's competencies are what make them competitive in the marketplace. If a company allows another company to take control of them, it loses that advantage.\nWhen deciding about contract manufacture, the company should weigh the benefits and associated risks. For small companies, contract manufacturing may not be a good business strategy. For large companies that are trying to extend into new markets, contract manufacturing may be a good choice.\nProtectionism.\nIn an international context, establishing a foreign subsidiary as a contract manufacturer can have favorable tax benefits for the parent company, allowing them to reduce overall tax liabilities and increase profits, depending upon the activities of the contract manufacturer. This is a form of true protectionism.\nThe iPad and iPhone, which are products of Apple Inc., are manufactured in China by Foxconn. Some devices may also be manufactured by Pegatron. Apple may move some fraction of iPhone assembly into the United States in the near future.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "52584796", "revid": "45370187", "url": "https://en.wikipedia.org/wiki?curid=52584796", "title": "Rapid casting", "text": "Rapid casting is an integration of investment casting with rapid prototyping/3D printing. In this technique disposable patterns that are used for forming molds are created with 3D printing techniques like fused deposition modeling, stereolithography or any other 3D printing technique.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "69346171", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=69346171", "title": "Overpackaging", "text": "Overpackaging is the use of excess packaging. The Institute of Packaging Professionals defines overpackaging as “a condition where the methods and materials used to package an item exceed the requirements for adequate containment, protection, transport, and sale” \nOverpackaging is an opportunity for source reduction, reducing waste before it is generated by proper package design and practice. Elimination of excess packaging is at the lead of the Reduce, reuse, recycle hierarchy. Use of minimized packaging is key to having sustainable packaging. Examples of overpackaging can be found in many areas; from e-commerce to retail food packaging.\nSome examples of overpackaging are obvious while others are more of a judgement call. For example, luxury packaging frequently uses more packaging than the minimum requirements. Brand managers believe that premium packaging is needed to communicate the extra value the contents. Also. gift wrapping can involve excess packaging but traditions and personal choices allow people to continue to use it. Decorative boxes are an \"art form\" which clearly exceed minimum functional requirements.\nExcess packaging by design.\nAn example of a wasteful package design is a breakfast cereal box (some other products also). This is typically a folding carton enclosing a plastic bag of cereal. Cartons are frequently tall and wide but very thin. This has a poor material to volume ratio and is very inefficient; it is very wasteful. Package designers are aware of this opportunity to save packaging costs, materials, and waste but marketing and merchandising people want the “billboard” style package for advertising and graphics. An optimized folding carton would use much less paperboard for the same volume of cereal, but with reduced room for graphics. Use of only a resealable plastic bag would use even less material per unit of cereal; Of course, even that option results with an empty plastic bag to discard.\nUnderfilled packages.\nUnderfilled or \"slackfill\" packaging is that which is intentionally too large for the contents, resulting in non-functional headspace. This not only risks charges of \"deceptive packaging\" but it involves excessive packaging: unnecessary packaging waste.\nE-commerce.\nSometimes a package is properly designed to protect its product for controlled distribution to a retail store; packaging is minimal. With online shopping or E-commerce, however, items packed for retail sale need to be shipped individually by the e-tailer or by a fulfillment house. The individual package is shipped and handled by package delivery or small parcel carriers. Retail packages are frequently packed into a larger corrugated box for shipment. Often these secondary boxes are much larger than needed, thus use void-fill to immobilize the contents. This can have the appearance of gross overpackaging. \nIf the product manufacturer designed all packaging to meet the requirements of individual shipment, then the portion delivered to a retail store would have excessive packaging.\nWith fragile items such as consumer electronics, engineers try to match the fragility of the product with the expected stresses of distribution handling. Package cushioning is used to help ensure safe delivery of the product. With overpackaging, excessive cushioning and a larger corrugated box are used: wasteful packaging. \nSometimes two levels of packaging are needed for separate distribution: one for palletize shipment to retail stores and the other designed for individual delivery to households, which results in production inefficiency. New package designs are sometimes called for.\nFood overwraps.\nFresh produce is usually presented for sale without packages, allowing shoppers to touch the items and choose which ones to buy. Some foods are over wrapped with shrink film, individually bagged, or further protected to increase the appeal to some customers. This extra packaging is sometimes considered excessive and unnecessary. ", "Engineering,_Manufacturing": 0.9884219766, "qwen": "Yes"}
{"id": "12783405", "revid": "1145908983", "url": "https://en.wikipedia.org/wiki?curid=12783405", "title": "Ironing (metalworking)", "text": "Ironing is a sheet metal forming process that uniformly thins the workpiece in a specific area. \nThis is a very useful process when employed in combination with deep drawing to produce a uniform wall thickness part with greater height-to-diameter ratio. One example of ironing can be found in the manufacture of aluminum beverage cans, which are actually pressed from flat sheets of thicker material.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "12792117", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=12792117", "title": "Package on a package", "text": "Package on a package (PoP) is an integrated circuit packaging method to vertically combine discrete logic and memory ball grid array (BGA) packages. Two or more packages are installed atop each other, i.e. stacked, with a standard interface to route signals between them. This allows higher component density in devices, such as mobile phones, personal digital assistants (PDA), and digital cameras, at the cost of slightly higher height requirements. Stacks with more than 2 packages are uncommon, due to heat dissipation considerations.\nConfiguration.\nTwo widely used configurations exist for PoP:\nDuring PCB assembly, the bottom package of a PoP stack is placed directly on the PCB, and the other package(s) of the stack are stacked on top.\nThe packages of a PoP stack become attached to each other (and to the PCB) during reflow soldering.\nBenefits.\nThe package on a package technique tries to combine the benefits of traditional packaging with the benefits of die-stacking techniques, while avoiding their drawbacks.\nTraditional packaging places each die in its own package, a package designed for normal PCB assembly techniques that place each package directly on the PCB side-by-side.\nThe 3D die-stacking system in package (SiP) techniques stacks multiple die in a single package, which has several advantages and also some disadvantages compared to traditional PCB assembly.\nIn embedded PoP techniques, chips are embedded in a substrate on the bottom of the package. This PoP technology enables smaller packages with shorter electrical connections and is supported by companies such as Advanced Semiconductor Engineering (ASE).\nAdvantages over traditional isolated-chip packaging.\nThe most obvious benefit is motherboard space savings. PoP uses much less PCB area, almost as little as stacked-die packages.\nElectrically, PoP offers benefits by minimizing track length between different interoperating parts, such as a controller and memory. This yields better electrical performance of devices, since shorter routing of interconnections between circuits yields faster signal propagation and reduced noise and cross-talk.\nAdvantages over chip stacking.\nThere are several key differences between stacked-die and stacked-package products.\nThe main financial benefit of package on a package is that the memory device is decoupled from the logic device. Therefore this gives PoP all the same advantages that traditional packaging has over stacked-die products:\nOther names.\nPackage on a package is also known by other names:\nHistory.\nIn 2001, a Toshiba research team including T. Imoto, M. Matsui and C. Takubo developed a \"System Block Module\" wafer bonding process for manufacturing 3D integrated circuit (3D IC) packages. The earliest known commercial use of a 3D package-on-package chip was in Sony's PlayStation Portable (PSP) handheld game console, released in 2004. The PSP hardware includes eDRAM (embedded DRAM) memory manufactured by Toshiba in a 3D package chip with two dies stacked vertically. Toshiba called it \"semi-embedded DRAM\" at the time, before later calling it a stacked \"chip-on-chip\" (CoC) solution.\nIn April 2007, Toshiba commercialized an eight-layer 3D chip package, the 16GB THGAM embedded NAND flash memory chip, which was manufactured with eight stacked 2GB NAND flash chips. The same month, (\"Package-on-package secure module having anti-tamper mesh in the substrate of the upper package\") was filed by Steven M. Pope and Ruben C. Zeta of Maxim Integrated. In September 2007, Hynix Semiconductor introduced 24-layer 3D packaging technology, with a 16GB flash memory chip that was manufactured with 24 stacked NAND flash chips using a wafer bonding process.", "Engineering,_Manufacturing": 0.9995191097, "qwen": "Yes"}
{"id": "1422787", "revid": "32018152", "url": "https://en.wikipedia.org/wiki?curid=1422787", "title": "Design rule checking", "text": "In electronic design automation, a design rule is a geometric constraint imposed on circuit board, semiconductor device, and integrated circuit (IC) designers to ensure their designs function properly, reliably, and can be produced with acceptable yield. Design rules for production are developed by process engineers based on the capability of their processes to realize design intent. Electronic design automation is used extensively to ensure that designers do not violate design rules; a process called design rule checking (DRC). DRC is a major step during physical verification signoff on the design, which also involves LVS (layout versus schematic) checks, XOR checks, ERC (electrical rule check), and antenna checks. The importance of design rules and DRC is greatest for ICs, which have micro- or nano-scale geometries; for advanced processes, some fabs also insist upon the use of more restricted rules to improve yield.\nDesign rules.\nDesign rules are a series of parameters provided by semiconductor manufacturers that enable the designer to verify the correctness of a mask set. Design rules are specific to a particular semiconductor manufacturing process. A design rule set specifies certain geometric and connectivity restrictions to ensure sufficient margins to account for variability in semiconductor manufacturing processes, so as to ensure that most of the parts work correctly.\nThe most basic design rules are shown in the diagram on the right. The first are single layer rules. A \"width\" rule specifies the minimum width of any shape in the design. A \"spacing\" rule specifies the minimum distance between two adjacent objects. These rules will exist for each layer of semiconductor manufacturing process, with the lowest layers having the smallest rules (typically 100 nm as of 2007) and the highest metal layers having larger rules (perhaps 400 nm as of 2007).\nA two layer rule specifies a relationship that must exist between two layers. For example, an \"enclosure\" rule might specify that an object of one type, such as a contact or via, must be covered, with some additional margin, by a metal layer. A typical value as of 2007 might be about 10 nm.\nThere are many other rule types not illustrated here. A \"minimum area\" rule is just what the name implies. Antenna rules are complex rules that check ratios of areas of every layer of a net for configurations that can result in problems when intermediate layers are etched. Many other such rules exist and are explained in detail in the documentation provided by the semiconductor manufacturer.\nAcademic design rules are often specified in terms of a scalable parameter, λ, so that all geometric tolerances in a design may be defined as integer multiples of λ. This simplifies the migration of existing chip layouts to newer processes. Industrial rules are more highly optimized, and only approximate uniform scaling. Design rule sets have become increasingly more complex with each subsequent generation of semiconductor process.\nSoftware.\nThe main objective of design rule checking (DRC) is to achieve a high overall yield and reliability for the design. If design rules are violated the design may not be functional. To meet this goal of improving die yields, DRC has evolved from simple measurement and Boolean checks, to more involved rules that modify existing features, insert new features, and check the entire design for process limitations such as layer density. A completed layout consists not only of the geometric representation of the design, but also data that provides support for the manufacture of the design. While design rule checks do not validate that the design will operate correctly, they are constructed to verify that the structure meets the process constraints for a given design type and process technology.\nDRC software usually takes as input a layout in the GDSII standard format and a list of rules specific to the semiconductor process chosen for fabrication. From these it produces a report of design rule violations that the designer may or may not choose to correct. Carefully \"stretching\" or waiving certain design rules is often used to increase performance and component density at the expense of yield.\nDRC products define rules in a language to describe the operations needed to be performed in DRC. For example, Mentor Graphics uses Standard Verification Rule Format (SVRF) language in their DRC rules files and Magma Design Automation is using Tcl-based language. A set of rules for a particular process is referred to as a run-set, rule deck, or just a deck.\nDRC is a very computationally intense task. Usually DRC checks will be run on each sub-section of the ASIC to minimize the number of errors that are detected at the top level. If run on a single CPU, customers may have to wait up to a week to get the result of a Design Rule check for modern designs. Most design companies require DRC to run in less than a day to achieve reasonable cycle times since the DRC will likely be run several times prior to design completion. With today's processing power, full-chip DRC's may run in much shorter times as quick as one hour depending on the chip complexity and size.\nSome example of DRC's in IC design include:\nCommercial.\nMajor products in the \"DRC\" area of \"EDA\" include:", "Engineering,_Manufacturing": 0.9998699427, "qwen": "Yes"}
{"id": "261987", "revid": "16528233", "url": "https://en.wikipedia.org/wiki?curid=261987", "title": "Kanban", "text": "Kanban (Japanese: カンバン and Chinese: 看板, meaning signboard or billboard) is a scheduling system for lean manufacturing (also called just-in-time manufacturing, abbreviated JIT). Taiichi Ohno, an industrial engineer at Toyota, developed kanban to improve manufacturing efficiency. The system takes its name from the cards that track production within a factory. Kanban is also known as the \"Toyota nameplate system\" in the automotive industry.\nIn kanban, problem areas are highlighted by measuring lead time and cycle time of the full process and process steps. One of the main benefits of kanban is to establish an upper limit to work in process (commonly referred as \"WIP\") inventory to avoid overcapacity. Other systems with similar effect exist, for example CONWIP. A systematic study of various configurations of kanban systems, such as \"generalized kanban\" or \"production authorization card\" (PAC) and \"extended kanban\", of which CONWIP is an important special case, can be found in Tayur (1993), and more recently Liberopoulos and Dallery (2000), among other papers.\nA goal of the kanban system is to limit the buildup of excess inventory at any point in production. Limits on the number of items waiting at supply points are established and then reduced as inefficiencies are identified and removed. Whenever a limit is exceeded, this points to an inefficiency that should be addressed.\nOrigins.\nThe system originates from the simplest visual stock replenishment signaling system, an empty box. This was first developed in the UK factories producing Spitfires during the Second World War, and was known as the \"two bin system.\" In the late 1940s, Toyota started studying supermarkets with the idea of applying shelf-stocking techniques to the factory floor. In a supermarket, customers generally retrieve what they need at the required time—no more, no less. Furthermore, the supermarket stocks only what it expects to sell in a given time, and customers take only what they need, because future supply is assured. This observation led Toyota to view a process as being a customer of one or more preceding processes and to view the preceding processes as a kind of store.\nKanban aligns inventory levels with actual consumption. A signal tells a supplier to produce and deliver a new shipment when a material is consumed. This signal is tracked through the replenishment cycle, bringing visibility to the supplier, consumer, and buyer.\nKanban uses the rate of demand to control the rate of production, passing demand from the end customer up through the chain of customer-store processes. In 1953, Toyota applied this logic in their main plant machine shop.\nOperation.\nA key indicator of the success of production scheduling based on demand, \"pushing,\" is the ability of the demand-forecast to create such a \"push\". Kanban, by contrast, is part of an approach where the \"pull\" comes from demand and products are made to order. Re-supply or production is determined according to customer orders.\nIn contexts where supply time is lengthy and demand is difficult to forecast, often the best one can do is to respond quickly to observed demand. This situation is exactly what a kanban system accomplishes, in that it is used as a demand signal that immediately travels through the supply chain. This ensures that intermediate stock held in the supply chain are better managed, and are usually smaller. Where the supply response is not quick enough to meet actual demand fluctuations, thereby causing potential lost sales, a stock building may be deemed more appropriate and is achieved by placing more kanban in the system.\nTaiichi Ohno stated that to be effective, kanban must follow strict rules of use. Toyota, for example, has six simple rules, and close monitoring of these rules is a never-ending task, thereby ensuring that the kanban does what is required.\nToyota's six rules.\nToyota has formulated six rules for the application of kanban:\nKanban (cards).\nKanban cards are a key component of kanban and they signal the need to move materials within a production facility or to move materials from an outside supplier into the production facility. The kanban card is, in effect, a message that signals a depletion of product, parts, or inventory. When received, the kanban triggers replenishment of that product, part, or inventory. Consumption, therefore, drives demand for more production, and the kanban card signals demand for more product—so kanban cards help create a demand-driven system.\nIt is widely held by proponents of lean production and manufacturing that demand-driven systems lead to faster turnarounds in production and lower inventory levels, helping companies implementing such systems be more competitive.\nIn the last few years, systems sending kanban signals electronically have become more widespread. While this trend is leading to a reduction in the use of kanban cards in aggregate, it is still common in modern lean production facilities to find the use of kanban cards. In various software systems, kanban is used for signalling demand to suppliers through email notifications. When stock of a particular component is depleted by the quantity assigned on kanban card, a \"kanban trigger\" is created (which may be manual or automatic), a purchase order is released with predefined quantity for the supplier defined on the card, and the supplier is expected to dispatch material within a specified lead-time.\nKanban cards, in keeping with the principles of kanban, simply convey the need for more materials. A red card lying in an empty parts cart conveys that more parts are needed.\nThree-bin system.\nAn example of a simple kanban system implementation is a \"three-bin system\" for the supplied parts, where there is no in-house manufacturing. One bin is on the factory floor (the initial demand point), one bin is in the factory store (the inventory control point), and one bin is at the supplier. The bins usually have a removable card containing the product details and other relevant information, the classic kanban card.\nWhen the bin on the factory floor is empty (because the parts in it were used up in a manufacturing process), the empty bin and its kanban card are returned to the factory store (the inventory control point). The factory store replaces the empty bin on the factory floor with the full bin from the factory store, which also contains a kanban card. The factory store sends the empty bin with its kanban card to the supplier. The supplier's full product bin, with its kanban card, is delivered to the factory store; the supplier keeps the empty bin. This is the final step in the process. Thus, the process never runs out of product—and could be described as a closed loop, in that it provides the exact amount required, with only one spare bin so there is never oversupply. This 'spare' bin allows for uncertainties in supply, use, and transport in the inventory system. A good kanban system calculates just enough kanban cards for each product. Most factories that use kanban use the colored board system (heijunka box).\nElectronic kanban.\nMany manufacturers have implemented electronic kanban (sometimes referred to as e-kanban) systems. These help to eliminate common problems such as manual entry errors and lost cards. E-kanban systems can be integrated into enterprise resource planning (ERP) systems, enabling real-time demand signaling across the supply chain and improved visibility. Data pulled from e-kanban systems can be used to optimize inventory levels by better tracking supplier lead and replenishment times.\nE-kanban is a signaling system that uses a mix of technology to trigger the movement of materials within a manufacturing or production facility. Electronic kanban differs from traditional kanban in using technology to replace traditional elements like kanban cards with barcodes and electronic messages like email or electronic data interchange.\nA typical electronic kanban system marks inventory with barcodes, which workers scan at various stages of the manufacturing process to signal usage. The scans relay messages to internal/external stores to ensure the restocking of products. Electronic kanban often uses the Internet as a method of routing messages to external suppliers and as a means to allow a real-time view of inventory, via a portal, throughout the supply chain.\nOrganizations like the Ford Motor Company and Bombardier Aerospace have used electronic kanban systems to improve processes. Systems are now widespread from single solutions or bolt on modules to ERP systems.\nTypes of kanban systems.\nIn a kanban system, adjacent upstream and downstream workstations communicate with each other through their cards, where each container has a kanban associated with it. Economic order quantity is important. The two most important types of kanbans are:\nThe Kanban philosophy and task boards are also used in agile project management to coordinate tasks in project teams. An online demonstration can be seen in an \"agile\" simulator.\nImplementation of kanban can be described in the following manner:\nKanbrain.\nA third type involves corporate training. Following the just-in-time principle, computer-based training permits those who need to learn a skill to do so when the need arises, rather than take courses and lose the effectiveness of what they've learned from lack of practice.", "Engineering,_Manufacturing": 0.9999914169, "qwen": "Yes"}
{"id": "262043", "revid": "2320974", "url": "https://en.wikipedia.org/wiki?curid=262043", "title": "Superplasticity", "text": "In materials science, superplasticity is a state in which solid crystalline material is deformed well beyond its usual breaking point, usually over about 400% during tensile deformation. Such a state is usually achieved at high homologous temperature. Examples of superplastic materials are some fine-grained metals and ceramics. Other non-crystalline materials (amorphous) such as silica glass (\"molten glass\") and polymers also deform similarly, but are not called superplastic, because they are not crystalline; rather, their deformation is often described as Newtonian fluid. Superplastically deformed material gets thinner in a very uniform manner, rather than forming a \"neck\" (a local narrowing) that leads to fracture. Also, the formation of microvoids, which is another cause of early fracture, is inhibited.\nSuperplasticity must not be confused with superelasticity.\nHistorical developments of superplasticity.\nSome evidence of superplastic-like flow in metals has been found in some artifacts, such as in Wootz steels in ancient India, even though superplasticity was first scientific recognition in the twentieth century in the report on 163% elongation in brass by Bengough in 1912. Later, Jenkins' higher elongation of 300% in Cd–Zn and Pb–Sn alloys in 1928. However, those works did not go further to set a new phenomenon of mechanical properties of materials. Until the work of Pearson was published in 1934, a significant elongation of 1950% was found in Pb–Sn eutectic alloy. It was easy to become the most extensive elongation report in scientific investigation at this time. There was no further interest in superplasticity in the Western World for more than 25 years after Pearson’s effort. Later, Bochvar and Sviderskaya continued superplasticity in the Soviet Union with many publications on Zn–Al alloys. A research institute focused on superplasticity, the Institute of Metals Superplasticity Problems, was established in 1985 in Ufa City, Russia. This institute has remained the only global institute to work exclusively to research in superplasticity. The interest in superplasticity rose in 1982 when the first major international conference on ‘Superplasticity in Structural Materials, edited by Paton and Hamilton, was held in San Diego. From there, numerous investigations have been published with considerable results. Superplasticity is now the background for superplastic deformation forming as an essential aerospace application technique. \nConditions.\nIn metals and ceramics, requirements for it being superplastic include a fine grain size (less than approximately 10 micrometers) and an operating temperature that is often from above a half absolute melting point. Several studies have found superplasticity in coarse-grain materials. However, the scientific community has agreed the grain size threshold at 10 micrometers is the precondition for activating superplasticity. Generally, grain growth at high-temperature, therefore maintaining the fine grain size structure at homologous temperature, is the main challenge in superplasticity research. The typical microstructure strategy uses a fine dispersion of thermally stable particles, which pin the grain boundaries and maintain the fine grain structure at the high temperatures and existence of multiple phases required for superplastic deformation. The alloy's most typical microstructure for superplasticity is eutectic or eutectoid structure, as found in Sn-Pb, or Zn-Alloy alloys. \nThose materials that meet these parameters must still have a strain rate sensitivity (a measurement of the way the stress on a material reacts to changes in strain rate) of >0.3 to be considered superplastic. The ideal strain rate sensitivity is 0.5, typically found in micro duplex alloys.\nMechanism.\nThe mechanisms of superplasticity in metals are determined as the Grain Boundary Sliding (GBS). However, the grain boundary sliding (GBS) can lead to the stress concentration at the triple junction or the grain boundary of the hard phases. Therefore, the GBS in polycrystal structured materials must be accompanied by other accommodation processes such as diffusion or dislocation. The diffusion models proposed by Ashby and Verall explain a gradual change in grain shapes to maintain the compatibility between the grains during the deformation. The changes in grain shape are operated by diffusion. The grain boundary migrates to form an equiaxed shape with a new orientation compared to the original grains. The dislocation model is explained as the stress concentration by GBS will be relaxed by dislocation motion in the blocking grains. The dislocation piles up, and the climb would allow another dislocation to be emitted. The further detail in dislocation model is still under debate, with several proposed by Crossman and Ashby, Langdon, and Gifkins model.\nHigh strain Rate Superplasticity.\nIn general, superplasticity often occurs at a slow strain rate, in order of 10−4 s−1, and can be energy-consuming. In addition, prolonged time exposed to high-operation temperature also degraded the mechanical properties of materials. There is a strong demand to increase the strain rate in superplastic deformation to the order of 10−2 s−1, called High strain Rate Superplasticity (HSRS). Increment of strain rate in superplastic deformation is generally achieved by reduction of grain size in the ultrafine range from 100 to less than 500 ums. Further grain refinement to nanocrystalline structure with grain size less than 100 nm is ineffective in raising the deformation rate or improving ductility. The most common grain refinement process for HSRS research uses Severe Plastic Deformation (SPD). SPD can fabricate exceptional grain refinement to the sub-micrometer or even the nanometer range. Among many SPD techniques, the two most widely used techniques are equal-channel angular pressing (ECAP) and high-pressure torsion (HPT). Besides producing the ultrafine grain size, these techniques also provide a high fraction of high-angle boundaries. These high-angle grain boundaries are a specific benefit to increase the strain rates of deformation. Of the importance of grain refinement processing to superplasticity research, ECAP and HPT have been devoted to mainstream positions in superplasticity studies in metals.\nAdvantages of superplastic forming.\nThe process offers a range of important benefits, from both the design and production aspects. To begin with there is the ability to form components with double curvature and smooth contours from single sheet in one operation, with exceptional dimensional accuracy and surface finish, and none of the \"spring back\" associated with cold forming techniques. Because only single surface tools are employed, lead times are short and prototyping is both rapid and easy, because a range of sheet alloy thicknesses can be tested on the same tool.\nForming techniques.\nThere are three forming techniques currently in use to exploit these advantages. The method chosen depends upon design and performance criteria such as size, shape, and alloy characteristics.\nCavity forming.\nA graphite-coated blank is put into a heated hydraulic press. Air pressure is then used to force the sheet into close contact with the mould. At the beginning, the blank is brought into contact with the die cavity, hindering the forming process by the blank/die interface friction. Thus, the contact areas divide the single bulge into a number of bulges, which are undergoing a free bulging process. The procedure allows the production of parts with relatively exact outer contours. This forming process is suitable for the manufacturing of parts with smooth, convex surfaces.\nBubble forming.\nA graphite coated blank is clamped over a 'tray' containing a heated male mould. Air pressure forces the metal into close contact with the mould. The difference between this and the female forming process is that the mould is, as stated, male and the metal is forced over the protruding form. For the female forming the mould is female and the metal is forced into the cavity.\nThe tooling consists of two pressure Chambers and a counter punch, which is linearly displaceable. Similar to the cavity forming technology, at the process beginning, the firmly clamped blank is bulged by gas pressure.\nThe second phase of the process involves the material being formed over the punch surface by applying a pressure against the previous forming direction. Due to a better material use, which is caused by process conditions, blanks with a smaller initial thickness compared to cavity forming can be used. Thus, the bubble forming technology is particularly suitable for parts with high forming depths.\nDiaphragm forming.\nA graphite coated blank is placed into a heated press. Air pressure is used to force the metal into a bubble shape before the male mold is pushed into the underside of the bubble to make an initial impression. Air pressure is then used from the other direction to final form the metal around the male mould. This process has long cycle times because the superplastic strain rates are low. Product also suffers from poor creep performance due to the small grain sizes and there can be cavitation porosity in some alloys. Surface texture is generally good however. With dedicated tooling, dies and machines are costly. The main advantage of the process is that it can be used to produce large complex components in one operation. This can be useful for keeping the mass down and avoiding the need for assembly work, a particular advantage for aerospace products. For example, the diaphragm-forming method (DFM) can be used to reduce the tensile flow stress generated in a specific alloy matrix composite during deformation.\nAluminium and aluminium based alloys.\nSuperplastically formed (SPF) aluminium alloys have the ability to be stretched to several times their original size without failure when heated to between 470 and 520 °C. These dilute alloys containing zirconium, later known by the trade name SUPRAL, were heavily cold worked to sheet and dynamically crystallized to a fine stable grain size, typically 4–5 μm, during the initial stages of hot deformation. Also superplastic forming is a net-shape processing technology that dramatically decreases fabrication and assembly costs by reducing the number of parts and the assembly requirements. Using SPF technology, it was anticipated that a 50% manufacturing cost reduction can be achieved for many aircraft assemblies, such as the nose cone and nose barrel assemblies. Other spin-offs include weight reduction, elimination of thousands of fasteners, elimination of complex featuring and a significant reduction in the number of parts. The breakthrough for superplastic Al-Cu alloys was made by Stowell, Watts and Grimes in 1969 when the first of several dilute aluminium alloys (Al-6% Cu-0.5%Zr) was rendered superplastic with the introduction of relatively high levels of zirconium in solution using specialized casting techniques and subsequent electrical treatment to create extremely fine precipitates.\nCommercial alloys.\nSome commercial alloys have been thermo-mechanically processed to develop superplasticity. The main effort has been on the Al 7000 series alloys, Al-Li alloys, Al-based metal-matrix composites, and mechanically alloyed materials.\nAluminium alloy composites.\nAluminium alloy and its composites have wide applications in automotive industries. At room temperature, composites usually have higher strength compared to its component alloy. At high temperature, aluminium alloy reinforced by particles or whiskers such as , and SiC can have tensile elongation more than 700%. The composites are often fabricated by powder metallurgy to ensure fine grain sizes and the good dispersion of reinforcements. The grain size that allows the optimal superplastic deformation to happen is usually 0.5~1 μm, less than the requirement of conventional superplasticity. Just like other superplastic materials, the strain rate sensitivity m is larger than 0.3, indicating good resistance against local necking phenomenon. A few aluminium alloy composites such as 6061 series and 2024 series have shown high strain rate superplasticity, which happens in a much higher strain rate regime than other superplastic materials. This property makes aluminium alloy composites potentially suitable for superplastic forming because the whole process can be done in a short time, saving time and energy.\nDeformation mechanism for aluminium alloy composites.\nThe most common deformation mechanism in aluminium alloy composites is grain boundary sliding (GBS), which is often accompanied by atom/dislocation diffusion to accommodate deformation. The GBS mechanism model predicts a strain rate sensitivity of 0.3, which agrees with most of the superplastic aluminium alloy composites. Grain boundary sliding requires the rotation or migration of very fine grains at relatively high temperature. Therefore, the refinement of grain size and the prevention of grain growth at high temperature is of importance.\nThe very high temperature (close to melting point) is also said to be related to another mechanism, interfacial sliding, because at high temperatures, partial liquids appear in the matrix. The viscosity of the liquid plays the main role to accommodate the sliding of adjacent grain boundaries. The cavitation and stress concentration caused by the addition of second phase reinforcements are inhibited by the flow of liquid phase. However, too much liquid leads to voids thus deteriorating the stability of the materials. So temperature close to but not exceeding too much the initial melting point is often the optimal temperature. The partial melting could lead to the formation of filaments at the fracture surface, which can be observed under scanning electron microscope. The morphology and chemistry of reinforcements also have influence on the superplasticity of some composites. But no single criterion has yet been proposed to predict their influences.\nMethods to improve superplasticity.\nA few ways have been suggested to optimize the superplastic deformation of aluminium alloy composites, which are also indicative for other materials:\nTitanium and titanium based alloys.\nIn the aerospace industry, Titanium alloys such as Ti–6Al–4V find extensive use in aerospace applications, not only because of their specific high temperature strength, but also because a large number of these alloys exhibit superplastic behavior. Superplastic sheet thermoforming has been identified as a standard processing route for the production of complex shapes, especially and are amenable to superplastic forming (SPF). However, in these alloys the additions of vanadium make them considerably expensive and so, there is a need for developing superplastic titanium alloys with cheaper alloying additions. The Ti-Al-Mn alloy could be such a candidate material. This alloy shows significant post-uniform deformation at ambient and near-ambient temperatures.\nTi-Al-Mn (OT4-1) alloy.\nTi-Al-Mn (OT4-1) alloy is currently being used for aero engine components as well as other aerospace applications by forming through a conventional route that is typically cost, labour and equipment intensive. The Ti-Al-Mn alloy is a candidate material for aerospace applications. However, there is virtually little or no information available on its superplastic forming behaviour. In this study, the high temperature superplastic bulge forming of the alloy was studied and the superplastic forming capabilities are demonstrated.\nThe bulging process.\nThe gas pressure bulging of metal sheets has become an important forming method. As the bulging process progresses, significant thinning in the sheet material becomes obvious. Many studies were made to obtain the dome height with respect to the forming time useful to the process designer for the selection of initial blank thickness as well as non-uniform thinning in the dome after forming.\nCase study.\nThe Ti-Al-Mn (OT4-1) alloy was available in the form of a 1 mm thick cold-rolled sheet. The chemical composition of the alloy. A 35-ton hydraulic press was used for the superplastic bulge forming of a hemisphere. A die set-up was fabricated and assembled with the piping system enabling not only the inert gas flushing of the die- assembly prior to forming, but also for the forming of components under reverse pressure, if needed. The schematic diagram of the superplastic forming set-up used for bulge forming with all necessary attachments and the photograph of the top (left) and bottom (right) die for SPF.\nA circular sheet (blank) of 118 mm diameter was cut from the alloy sheet and the cut surfaces polished to remove burrs. The blank was placed on the die and the top chamber brought in contact. The furnace was switched on to the set temperature. Once the set temperature was reached the top chamber was brought down further to effect the required blank holder pressure. About 10 minutes were allowed for thermal equilibration. The argon gas cylinder was opened to the set pressure gradually. Simultaneously, the linear variable differential transformer (LVDT), fitted at the bottom of the die, was set for recording the sheet bulge. Once the LVDT reached 45 mm (radius of bottom die), gas pressure was stopped and the furnace switched off. The formed components were taken out when the temperature of the die set had dropped to 600 °C. Easy removal of the component was possible at this stage. Superplastic bulge forming of hemispheres were carried out at temperatures of 1098, 1123, 1148, 1173, 1198 and 1223 K (825, 850, 875, 900, 925 and 950 °C) at forming pressures of 0.2, 0.4, 0.6 and 0.87 MPa. As the bulge forming process progresses, significant thinning in the sheet material becomes obvious. An ultrasonic technique was used to measure the thickness distribution on the profile of the formed component. The components were analyzed in terms of the thickness distribution, thickness strain and thinning factor. Post deformation micro-structural studies were conducted on the formed components in order to analyze the microstructure in terms of grain growth, grain elongation, cavitations, etc.\nResults and discussions.\nThe microstructure of the as-received material with a two-dimensional grain size of 14 μm is shown in Fig. 8. The grain size was determined using the linear intercept method in both the longitudinal and transverse directions of the rolled sheet.\nSuccessful superplastic forming of hemispheres were carried out at temperatures of 1098, 1123, 1148, 1173, 1198 and 1223 K and argon gas forming pressures of 0.2, 0.4, 0.6 and 0.8 MPa. A maximum time limit of 250 minutes was given for the complete forming of the hemispheres. This cut-off time of 250 minutes was given for practical reasons. Fig. 9 shows a photo-graph of the blank (specimen) and a bulge formed component (temperature of 1123 K and a forming gas pressure of 0.6 MPa).\nThe forming times of successfully formed components at different forming temperatures and pressures. From the travel of the LVDT fitted at the bottom of the die (which measured the bulge height/depth) an estimate of the rate of forming was obtained. It was seen that the rate of forming was rapid initially and decreased gradually for all the temperature and pressure ranges as reported in Table 2. At a particular temperature, the forming time reduced as the forming pressure was increased. Similarly at a given forming pressure, forming time decreased with an increase in temperature.\nThe thickness of the bulge profile was measured at 7 points including the periphery (base) and pole. These points were selected by taking the line between centre of the hemisphere and base point as reference and offsetting by 15° until the pole point was reached. Hence the points 1, 2, 3, 4 and 5 subtend an angle of 15°, 30°, 45°, 60° and 75° respectively with the base of the hemisphere as shown in Fig. 10. The thickness was measured at each of these points on the bulge profile by using an ultrasonic technique. The thickness values for each of the successfully formed hemispherical components.\nFig. 11 shows the pole thickness of fully formed hemispheres as a function of forming pressure at different temperatures. At a particular temperature the pole thickness reduced as the forming pressure was increased. For all the cases studied the pole thickness lay in the range of about 0.3 to 0.4 mm from the original blank thickness of 1 mm.\nThe thickness strain formula_1, where formula_2 is the local thickness and formula_3 is the initial thickness, was calculated at different locations for all the successfully formed components. For a particular pressure the thickness strain reduced as the forming temperature was increased. Fig. 12 shows the thickness strain, formula_1 as a function of position along the dome cross section in case of a component formed at 1123 K at a forming pressure of 0.6 MPa.\nThe post-formed microstructure revealed that there was no significant change in grain size. Fig. 13 shows the microstructure of the bulge formed component at the base and the pole for a component formed at a temperature of 1148 K and forming pressure of 0.6 MPa. These microstructures show no significant change in grain size.\nConclusion.\nThe high temperature deformation behaviour and superplastic forming capability of a Ti-Al-Mn alloy was studied. Successful forming of 90 mm diameter hemispheres using the superplastic route were carried out at the temperature range of 1098 to 1223 K and forming pressure range of 0.2 to 0.8 MPa. The following conclusions could be drawn:\nIron and steel.\nMostly on non-qualified materials, such as austenitic steel of the Fe-Mn-Al alloy, which has some of the specific material parameters closely related to microstructural mechanisms. These parameters are used as indicators of material superplastic potentiality. The material was submitted to hot tensile testing, within a temperature range from 600 °C to 1000 °C and strain-rates varying from 10−6 to 1 s−1. The strain rate sensitivity parameter (m) and observed maximum elongation until rupture (εr) could be determined and also obtained from the hot tensile test.\nFe with Mn and Al alloys.\nThe experiments stated a possibility of superplastic behaviour in a Fe-Mn-Al alloy within a temperature range from 700 °C to 900 °C with grain size around 3 μm (ASTM grain size 12) and average strain rate sensitivity of m ∼ 0.54, as well as a maximum elongation at rupture around 600%.\nFe with Al and Ti alloys.\nThe superplastic behaviour of Fe-28Al, Fe-28Al-2Ti and Fe-28Al-4Ti alloys has been investigated by tensile testing, optical microscopy and transmission electron microscopy. Tensile tests were performed at 700–900 °C under a strain rate range of about 10−5 to 10−2/s. The maximum strain rate sensitivity index m was found to be 0.5 and the largest elongation reached 620%. In Fe3Al and Fe Al alloys with grain sizes of 100 to 600μm exhibit all deformation characteristics of conventional fine grain size superplastic alloys.\nHowever, superplastic behaviour was found in large-grained iron aluminides without the usual requisites for superplasticity of a fine grain size and grain boundary sliding. Metallographic examinations have shown that the average grain size of large-grained iron aluminides decreased during superplastic deformation.\nCeramics.\nThe properties of ceramics.\nThe properties of ceramic materials, like all materials, are dictated by the types of atoms present, the types of bonding between the atoms, and the way the atoms are packed together. This is known as the atomic scale structure. Most ceramics are made up of two or more elements. This is called a compound. For example, alumina , is a compound made up of aluminium atoms and oxygen atoms.\nThe atoms in ceramic materials are held together by a chemical bond. The two most common chemical bonds for ceramic materials are covalent and ionic. For metals, the chemical bond is called the metallic bond. The bonding of atoms together is much stronger in covalent and ionic bonding than in metallic. That is why, generally speaking, metals are ductile and ceramics are brittle. Due to ceramic materials wide range of properties, they are used for a multitude of applications. In general, most ceramics are:\nHigh-strain-rate superplasticity has been observed in aluminium-based and magnesium-based alloys. But for ceramic materials, superplastic deformation has been restricted to low strain rates for most oxides, and nitrides with the presence of cavities leading to premature failure. Here we show that a composite ceramic material consisting of tetragonal zirconium oxide, magnesium aluminates spinal and alpha-alumina phase exhibit superplasticity at strain rates up to 1.0 s−1. The composite also exhibits a large tensile elongation, exceeding 1050% or a strain rate of 0.4 s−1.\nSuperplastic metals and ceramics have the ability to deform over 100% without fracturing, permitting net-shape forming at high temperatures. These intriguing materials deform primarily by grain boundary sliding, a process accelerated with a fine grain size. However, most ceramics that start with a fine grain size experience rapid grain growth during high temperature deformation, rendering them unsuitable for extended superplastic forming. One can limit grain growth using a minor second phase (Zener pinning) or by making a ceramic with three phases, where grain to grain contact of the same phase is minimized. A research on fine grain three phase alumina-mullite-zirconia, with approximately equal volume fractions of the three phases, demonstrates that superplastic strain rates as high as 10−2/sec at 1500 °C can be reached. These high strain rates put ceramic superplastic forming into the realm of commercial feasibility.\nCavitations.\nSuperplastic forming will only work if cavitations don't occur during grain boundary sliding, those cavitations leaving either diffusion accommodation or dislocation generation as mechanisms for accommodating grain boundary sliding. The applied stresses during ceramic superplastic forming are moderate, usually 20–50 MPa, usually not high enough to generate dislocations in single crystals, so that should rule out dislocation accommodation. Some unusual and unique features of these three phase superplastic ceramics will be revealed, however, indicating that superplastic ceramics may have a lot more in common with metals than previously thought.\nYttria-stabilized tetragonal zirconia polycrystalline.\nYttrium oxide is used as the stabilizer. This material is predominantly tetragonal in structure. Y-TZP has the highest flexural strength of all the zirconia based materials. The fine grain size of Y-TZP lends itself to be used in cutting tools where a very sharp edge can be achieved and maintained due to its high wear resistance. It is considered to be the first true polycrystalline ceramic shown to be superplastic with a 3-mol %\nY-TZP (3Y-TZP), which is now considered to be the model ceramic system.\nThe fine grade size leads to a very dense, non-porous ceramic with excellent mechanical strength, corrosion resistance, impact toughness, thermal shock resistance and very low thermal conductivity. Due to its characteristics Y-TZP is used in wear parts, cutting tools and thermal barrier coatings.\nGrain size.\nSuperplastic properties of 3Y-TZP is greatly affected by grain size as displaced in Fig. 3, elongation to failure decreases and flow strength increases while grain size increases. A study was made on the dependence of flow stress on grain size, the result –in summary- shows that the flow stress approximately depends on the grain size squared:\nWhere:\nAlumina .\nAlumina is probably one of the most widely used structural ceramics, but superplasticity is difficult to obtain in alumina, as a result of rapid anisotropic grain growth during high-temperature deformation.\nRegardless of which, several studies have been performed on superplasticity in doped, fine-grain .Demonstrated that the grain size of containing 500-ppm MgO can be further refined by adding various dopants, such as , and . A grain size of about 0.66 μm was obtained in a 500-ppm -doped . As a result of this fine grain size, the exhibits a rupture elongation of 65% at 1450 °C under an applied stress of 20 MPa.", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "68033886", "revid": "917223", "url": "https://en.wikipedia.org/wiki?curid=68033886", "title": "Chavadipalayam railway station", "text": "Chavadipalayam railway station is a station near Erode in Tamil Nadu, India. It is located along the Erode–Tiruchirappalli line between and .\nGoods terminal.\nA goods terminal has been developed by a private sector company in this station. It has a facility to serve goods traffic of half rake/full rake inward and outward goods from locals through booking. ", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "25660882", "revid": "1053540", "url": "https://en.wikipedia.org/wiki?curid=25660882", "title": "Footprint (electronics)", "text": "A footprint or land pattern is the arrangement of pads (in surface-mount technology) or through-holes (in through-hole technology) used to physically attach and electrically connect a component to a printed circuit board. The land pattern on a circuit board matches the arrangement of leads on a component.\nComponent manufacturers often produce multiple pin-compatible product variants to allow systems integrators to change the exact component in use without changing the footprint on the circuit board. This can provide large cost savings for integrators, especially with dense BGA components where the footprint pads may be connected to multiple layers of the circuit board.\nMany component vendors provide footprints for their components, including Texas Instruments, and CUI. Other sources include third party libraries, such as SnapEDA.", "Engineering,_Manufacturing": 0.9998685122, "qwen": "Yes"}
{"id": "18021160", "revid": "25049592", "url": "https://en.wikipedia.org/wiki?curid=18021160", "title": "Product optimization", "text": "Production optimization is the practice of making changes or adjustments to a product to make it more desirable.\nDescription.\nA product has a number of attributes. For example, a soda bottle can have different packaging variations, flavors, nutritional values. It is possible to optimize a product by making minor adjustments. Typically, the goal is to make the product more desirable and to increase marketing metrics such as Purchase Intent, Believability, Frequency of Purchase, etc. \nMethods.\nMultivariate optimization is one of the most common methods for product optimization. In this method, multiple product attributes are specified and then tested with consumers. \nDue to complex interaction effects between different attributes (for example, consumers frequently associate certain flavors with packaging colors), it is problematic to use mathematical methods, such as Conjoint Analysis, typically used in industrial process optimization.\nMore recently companies started to adopt Evolutionary Optimization techniques for Product optimization. Evolutionary algorithms (such as IDDEA) are used to optimize products, concepts and messaging.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "13341817", "revid": "753665", "url": "https://en.wikipedia.org/wiki?curid=13341817", "title": "Hesa Air Base", "text": "Hesa Air Base belongs to the Iran's Aircraft Manufacturing Industrial Company HESA and it has been built near of Esfahan.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "13346325", "revid": "46317386", "url": "https://en.wikipedia.org/wiki?curid=13346325", "title": "Decambering", "text": "Decambering is the metalworking process of removing camber, or horizontal bend, from strip shaped materials. The material may be finite length sections or continuous coils. Decambering resembles flattening or levelling processes, but deforms the material edge (left or right) instead of the face (up or down) of the strip.\nProcesses.\nDecambering may be accomplished by a choice of several processes:\nThe material may be \"stretchformed\" or stretched typically 1-2% elongation past its elastic limit, such that the camber is strained out, and the strip relaxes straight. Typically this is accomplished by routing the strip through two sets of 180 degree or more wrap driven \"bridle rolls\" with the second rolls rotating faster than the first. Cut strip can be gripped each end then stretched on a static rig with one end being mechanically pulled. The \"stretchforming\" process is most suited to thin strip.\nWider material can be flat rolled with the rolls tilting such that the \"short\" edge is lengthened, with thickness slightly reduced, to equal the \"long\" edge. The material is then straight if properly processed. Several different types of these machines are available, ranging from position controlled to pressure controlled machines. Also, machines are available with automatic self checking features. If the material has residual stress as in toothed bandsaw blades, the rolls must not uniformly apply cross strain, as the inherent strain will distort the strip. In these cases, rolls exert corrective strain in a linear narrow strip inboard of the edge each side. In the case of sawblades with teeth on, the corrective squeezed strip on the toothed edge is located along the tooth gullet, and corrective squeeze on the toothed side must be about 2.5 times the corrective force on the plain edge.\nIf the strip is narrow and thick enough, side rolls with guide grooves can be used to bend the material laterally to remove the camber. There are many patented designs of these machines, with the best engaging the material on both edges of the strip over the worked portion, preventing the material from twisting or \"cheating\" the corrective lateral bending.\nNote that camber is often caused by slitting, where slitting knives extend the edge being slit. Outer edges left untreated usually have a shorter length than the inner edges being formed by slitting. The outer mults from slitting will therefore usually have camber, while inner mults frequently will not. Decamberers are cost effective when material is not laterally straight enough to suit a given process, and needs upgrading. Cambered material is usually lower in cost than straight material, and decamberers offer savings in these cases. Various types of decambering machines cater to wide or narrow materials.\nReferences.\n\"Decamberer Maintains Lock Bar Straightness\" by J. Neiland Pennington, Senior Editor, Modern Metals magazine pp 26–28, July 1997, Trend Publishing, Inc. Chicago, Il 60611–3110.\nUS patent US6038904 \"Decamberer\" 2000-03-21, Barnes, Austen\nUS patent US5904058 \"Decamberer\" 1999-05-18 Barnes, Austen\nGerman patent DE19857278 \"Camber correction for wide strip in rolling mill using pneumatic cylinder actuators to control pressure applied by rolls\" 2000-06-21 Barnes, Austen Bernard", "Engineering,_Manufacturing": 0.9990635514, "qwen": "Yes"}
{"id": "13348308", "revid": "40581682", "url": "https://en.wikipedia.org/wiki?curid=13348308", "title": "Bolpur Lok Sabha constituency", "text": "Bolpur Lok Sabha constituency is in West Bengal, in India. While four assembly segments of No. 41 Bolpur Lok Sabha constituency are in Birbhum district, three are in Purba Bardhaman district. The seat was a free seat till 2004, but was declared reserved for scheduled castes from 2009 general elections.\nVidhan Sabha segments.\nAs per order of the Delimitation Commission issued in 2006 in respect of the delimitation of constituencies in the West Bengal, parliamentary constituency no. 41 Bolpur, reserved for Scheduled castes (SC), is composed of the following assembly segments: \nPrior to delimitation, Bolpur Lok Sabha constituency was composed of the following assembly segments:Ausgram (SC) (assembly constituency no. 267), Mangalkot (assembly constituency no. 281), Nanoor (SC) (assembly constituency no. 283), Bolpur (assembly constituency no. 284), Labpur (assembly constituency no. 285), Dubrajpur (assembly constituency no. 286) and Mayureswar (SC) (assembly constituency no. 290)\nElection results.\nGeneral election 2019.\n \nGeneral election 2014.\n \n1984 Election.\nBy-election 1985.\nA by-election was held in this constituency in 1985 which was necessitated by the Sudden Death of sitting CPIM-MP Dr. Saradish Roy. In the by-election, Somnath Chatterjee of CPIM defeated his nearest rival Siddhartha Shankar Ray of Congress by 98,999 votes.\nGeneral elections 1967-2004.\nMost of the contests were multi-cornered. However, only winners and runners-up are mentioned below:", "Engineering,_Manufacturing": 0.9948117733, "qwen": "Yes"}
{"id": "13355219", "revid": "34029739", "url": "https://en.wikipedia.org/wiki?curid=13355219", "title": "Surfware", "text": "Surfware, Inc. is a Camarillo, CA-based company involved in the development of CAD/CAM software.\nCompany history.\nIn 1950, Victor Diehl opened a mold shop in Southern California for machine tooling medical products. Throughout the 1950s, Victor Diehl focused on precision mold products for the medical industry. In the 1960s, Victor and Alan Diehl got a numerical control machine (CNC) to expedite tooling of components for aircraft manufacturing. Ten years later, Alan and his brother-in-law Jack Epps, a physicist, built a smart NC machine powered by a mini-computer.\nIn 1980, Bryan and Larry Diehl, joined the machining firm and wrote a UNIX program for surface modeling and machining. In 1988, Surfware, Inc. was formed by Alan and Larry, and SURFCAM was launched—a PC-based modeling and NC programming software to be offered to the CAD/CAM industry.\nOver the next decade, SURFCAM's features advanced along with the capabilities of the PC. Started with NURBS surface technology on a PC, PC-based four-axis machining, CAM system for 32-bit architectures, PC CAM system with automatic rendering of blended surfaces, 2- and 3-axis rest machining.\nIn 2002, Surfware began work on what would become the TrueMill technology, a completely new toolpath strategy that controls the load on the tool to significantly increase CNC productivity extending also tool life for all materials, including aluminum, steels, titanium, Inconel and other exotics. SURFCAM Velocity Powered by Truemill was launched in 2005, this CAD/CAM software limits the maximum stepover to cut optimally everywhere along the toolpath on any part geometry. A patent (US 7,451,013) has been granted to Surfware.Inc for its “Engagement Milling” technology (TrueMill).\nSurfware headquarters in Thousand Oaks, California. It maintains its own suite of milling machines to test the latest developments and innovations in the state-of-the-art TrueMill technology.\nIn 2013 Surfcam was acquired by \nIn 2014 Vero Software was acquired by ", "Engineering,_Manufacturing": 0.9999963045, "qwen": "Yes"}
{"id": "69514117", "revid": "764407", "url": "https://en.wikipedia.org/wiki?curid=69514117", "title": "ZW Drive", "text": "Shenzhen Zhaowei, commonly known as ZW Drive, is a Shenzhen-based manufacturer of power transmission systems and gearboxes, including micro planetary gearboxes, precision reduction gear boxes, plastic and metal powder-based injection parts and its assemblies. The company also operates five fully-owned subsidiaries.\nCompany history.\nThe company was incorporated in 2001. It is active in micro drive systems, gearboxes, gear motor, encoders, and controls. It reported a net profit of 244.7 million yuan in 2020. Zhaowei is listed on the Shenzhen Stock Exchange, completed its successful initial public offering (IPO) in December 2020.\nPrecision gear mold design and development.\nIn terms of gear mold design, after years of technology accumulation, the company has mastered the core key technologies of gear mold cavity design methods and tooth shape correction.", "Engineering,_Manufacturing": 0.994276464, "qwen": "Yes"}
{"id": "69529675", "revid": "7178531", "url": "https://en.wikipedia.org/wiki?curid=69529675", "title": "2011 Abia State House of Assembly election", "text": "The 2011 Abia State House of Assembly election was held on April 26, 2011, to elect members of the Abia State House of Assembly in Nigeria. All the 24 seats were up for election in the Abia State House of Assembly.\nResults.\nOsisioma South.\nPDP candidate Emeka Alozie won the election.\nUmuahia North.\nPDP candidate Emeka Ejiogu won the election.\nUmuahia Central.\nPDP candidate Grace Nkera Uche won the election.\nIsiala Ngwa North.\nPDP candidate Martins Azubuike won the election.\nIsiala Ngwa South.\nPDP candidate Darlington Nwokocha won the election.\nIsuikwuato.\nPDP candidate Chukwudi Ogele won the election.\nUmuahia East.\nPDP candidate Chidiebere Nwoke won the election.\nUmunneochi.\nPDP candidate Ikedi Ezekwesiri won the election.\nUkwa West.\nPDP candidate Mezie Nwaubani won the election.\nUkwa East.\nPDP candidate Allwell Asiforo Okere won the election.\nObingwa East.\nPDP candidate Princewill Chilaka won the election.\nObingwa West.\nPDP candidate Uche Nwankpa won the election.\nUmuahia South.\nPDP candidate Chidi Nwosu won the election.\nIkwuano.\nPDP candidate Emeka Osoagbaka won the election.\nUgwunagbo.\nPDP candidate Humphery Azubuike won the election.\nOhafia North.\nPDP candidate Ude Oko Chukwu won the election.\nAba Central.\nPDP candidate Kate Maduako won the election.\nOsisioma North.\nPDP candidate Ikechukwu Nwabeke won the election.\nAba North.\nPDP candidate Blessing Nwagba won the election.\nArochukwu.\nPDP candidate Agwu U. Agwu won the election.\nAba South.\nPDP candidate Nwogu Iheasinmo won the election.\nBende North.\nPDP candidate Ndukwe Ojukwu won the election.\nBende South.\nPDP candidate Princewill Onyegbu won the election.\nOhafia South.\nPDP candidate Mba Ukaha won the election.", "Engineering,_Manufacturing": 0.9999873638, "qwen": "Yes"}
{"id": "69536500", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=69536500", "title": "Advanced packaging (semiconductors)", "text": "Advanced packaging is the aggregation and interconnection of components before traditional integrated circuit packaging. Advanced packaging allows multiple devices (electrical, mechanical, or semiconductor) to be merged and packaged as a single electronic device. Unlike traditional integrated circuit packaging, advanced packaging employs processes and techniques that are performed at semiconductor fabrication facilities. Advanced packaging thus sits between fabrication and traditional packaging -- or, in other terminology, between BEoL and post-fab. Advanced packaging includes multi-chip modules, 3D ICs, 2.5D ICs, heterogeneous integration, fan-out wafer-level packaging, system-in-package, quilt packaging, combining logic (processors) and memory in a single package, die stacking, several chiplets or dies in a package, combinations of these techniques, and others.\nAdvanced packaging can help achieve performance gains through the integration of several devices in one package and associated efficiency gains (by reducing the distances signals have to travel, in other words reducing signal paths), and allowing for high numbers of connections between devices, without having to resort to smaller transistors which have become increasingly more difficult to manufacture.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "69557215", "revid": "327289", "url": "https://en.wikipedia.org/wiki?curid=69557215", "title": "1999 Abia State House of Assembly election", "text": "The 1999 Abia State House of Assembly election was held on January 9, 1999, to elect members of the Abia State House of Assembly in Nigeria. All the 24 seats were up for election in the Abia State House of Assembly.\nResults.\nOsisioma South.\nAPP candidate Donatus Nwankpa won the election.\nUmuahia North.\nPDP candidate Nkem Chris Ike won the election.\nUmuahia Central.\nPDP candidate Stanley Ohajuruka won the election.\nIsiala Ngwa North.\nPDP candidate Christopher Enweremadu won the election.\nIsiala Ngwa South.\nAPP candidate Remigius Nji won the election.\nIsuikwuato.\nPDP candidate Ernest Osita Igbe won the election.\nUmuahia East.\nAPP candidate Dan Egbogu won the election.\nUmunneochi.\nPDP candidate Matthew Ibeh won the election.\nUkwa West.\nPDP candidate Ngozi Ulunwa won the election.\nUkwa East.\nPDP candidate Emeka Stanley won the election.\nObingwa East.\nPDP candidate Eric Acho Nwakanma won the election.\nObingwa West.\nPDP candidate Chima Ochieze won the election.\nUmuahia South.\nAPP candidate Ndukwe Adindu won the election.\nIkwuano.\nPDP candidate Wisdom Ogbonna won the election.\nUgwunagbo.\nPDP candidate James Maraizu won the election.\nOhafia North.\nPDP candidate Tony Okoro Kalu won the election.\nAba Central.\nPDP candidate Nnamdi Egege won the election.\nOsisioma North.\nPDP candidate Kingsley Mgbeahuru won the election.\nAba North.\nAPP candidate Blessing Azuru won the election.\nArochukwu.\nPDP candidate Sampson Orji won the election.\nAba South.\nAPP candidate Obioma Ekpem won the election.\nBende North.\nPDP candidate Lekwauwa Orji won the election.\nBende South.\nPDP candidate Emenike Okoroafor won the election.\nOhafia South.\nPDP candidate Bernard Orji won the election.", "Engineering,_Manufacturing": 1.0000008345, "qwen": "Yes"}
{"id": "26321983", "revid": "7314633", "url": "https://en.wikipedia.org/wiki?curid=26321983", "title": "Diamond grinding cup wheel", "text": "A diamond grinding cup wheel is a metal-bonded diamond tool with diamond segments welded or cold-pressed on a steel (or other metal, such as aluminum) wheel body, which usually looks like a cup. Diamond grinding cup wheels are usually mounted on concrete grinders to grind abrasive building materials like concrete, granite and marble.\nUse.\nThere are various styles and specifications of diamond grinding cup wheels to fit various application requirements. The ones with many big diamond segments can undertake heavy workloads, for example, grinding concrete and stone, while those with small or sparse diamond segments are normally used for fast removal of paints, wallpapers, glues, epoxy and other surface coatings.\nJust like other metal-bonded diamond tools, the diamond segments on diamond grinding cup wheels can have different bonds, different diamond grits, different diamond quality and different diamond concentrations to fit different uses. For example, if the material to be ground is hard, the bond should be softer, and if the material is relatively soft, the bond should be harder.\nDiamond grinding cup wheels are used in different-roughness grindings. For coarse grinding, the bond should be softer and the diamonds' quality should be higher, because in this case the diamonds become blunt more easily. The diamond grit should be bigger, normally from 35 grit to 50 grit. For this is coarse grinding and big grit can improve working efficiency. The diamond concentration can be lower.\nFor fine grinding (sometimes called \"polishing\"), the bond should be harder and the diamonds' quality can be lower, as in this case the diamonds can last longer and a hard bond can also help the precision of the process. The diamond grit is normally between 80 grit and 120 grit, depending on the grinding requirements. The diamond concentration should be higher.\nAfter being ground, the material can be further polished with resin-bonded diamond polishing pads of different diamond grits.\nManufacturing methods.\nThere are two common methods to manufacture diamond grinding cup wheels: hot pressing and cold pressing.\nThe hot pressing method is to directly sinter the diamond segments in molds under a certain pressure in the dedicated sintering press machine, and then fix or connect the diamond segments onto the grinding wheel’s body via high-frequency welding, laser welding or mechanical mosaic method.\nThe cold pressing method is to first press the working layer (containing diamonds) and the transitive layer (not containing diamonds) of the diamond segments to their forms directly on the grinding wheel's body, and let the segments connect with the wheel's body via teeth, slots or other manners. Then, put the grinding wheels into sintering furnaces to sinter without press.", "Engineering,_Manufacturing": 1.000007987, "qwen": "Yes"}
{"id": "344127", "revid": "1461430", "url": "https://en.wikipedia.org/wiki?curid=344127", "title": "Signal trace", "text": "In electronics, a signal trace or circuit trace on a printed circuit board (PCB) or integrated circuit (IC) is the equivalent of a wire for conducting signals. Each trace consists of a flat, narrow part of the copper foil that remains after etching. Signal traces are usually narrower than power or ground traces because the current carrying requirements are usually much less.", "Engineering,_Manufacturing": 0.9987394214, "qwen": "Yes"}
{"id": "10262329", "revid": "4584133", "url": "https://en.wikipedia.org/wiki?curid=10262329", "title": "Anisotropic conductive film", "text": "Anisotropic conductive film (ACF) is an adhesive interconnect system that is commonly used in liquid crystal display manufacturing to make the electrical and mechanical connections from the driver electronics to the glass substrates of the LCD. The material is also available in a paste form referred to as anisotropic conductive paste (ACP), and both are grouped together as anisotropic conductive adhesives (ACAs). ACAs have more recently been used to perform the flex-to-board or flex-to-flex connections used in handheld electronic devices such as mobile phones, MP3 players, or in the assembly of CMOS camera modules.\nHistory.\nACAs developed in the late 1970s and early 1980s, with heat seal connectors by Nippon Graphite Industries, and ACFs by Hitachi Chemicals and Dexerials (formerly known as Sony Chemicals & Information Devices). Currently there are many manufacturers of heat seal connectors and ACAs, but Hitachi and Sony continue to dominate the industry in terms of market share. Other manufacturers of ACAs include 3M, Loctite, DELO, Creative Materials, Henkel, Sun Ray Scientific, Kyocera, Three Bond, Panacol, and Btech.\nIn the very early years, ACAs were made from rubber, acrylic, and other adhesive compounds, but they rapidly converged on several different variations of thermoset biphenyl type epoxy resins. The temperatures required were relatively high at 170-180C, however, and the market leaders Sony and Hitachi developed and released acrylic-based materials in the early 2000s that brought the curing temperatures down below 150C while keeping the curing times in the 10–12 second range. Further advances in the acrylic compounds used decreased the curing cycle times to below 5 seconds in many cases, which is where they remain as of this writing. Specification sheets are available at all of the manufacturers' sites listed above.\nCurrent market.\nACF continues to be the most popular form factor for ACAs, largely due to the ability to precisely control the volume of material, density of the particles in any sample, and the distribution of those particles within the sample. This is particularly true in the traditional ACF stronghold of display interconnects, but ACF has also seen strong growth out of the display industry and into areas long dominated by surface-mount technologies. The ability to make interconnections in a very small XYZ space has been the key driver in this expansion, helped by the ability under certain conditions to greatly lower cost either by the reduction of component counts or total material used.\nACPs are widely used in lower-end applications, primarily in the assembly of chips on to RFID antenna substrates. They are also used in some board or flex assembly applications, but at a much lower level than ACFs. While ACPs are generally lower cost than ACFs, they cannot provide the same level of control in adhesive quantity and particle dispersion as ACF. For this reason it is very difficult to use them for high-density applications.\nTechnology overview.\nACF technology is used in chip-on-glass (COG), flex-on-glass (FOG), flex-on-board (FOB), flex-on-flex (FOF), chip-on-flex (COF), chip-on-board (COB), and similar applications for higher signal densities and smaller overall packages. ACPs are typically used only in chip-on-flex (COF) applications with low densities and cost requirements, such as for RFID antennas, or in FOF and FOB assemblies in handheld electronics. COG, in particular, also uses gold bumps to connect to the display.\nIn all cases the anisotropic material, for example, a thermosetting resin containing conductive particles, is first deposited on the base substrate. This may be done using a lamination process for ACF, or either a dispense or printing process for ACP. The device or secondary substrate is then placed in position over the base substrate and the two sides are pressed together to mount the secondary substrate or device to the base substrate. In many cases this mounting process is done with no heat or a minimal amount of heat that is just sufficient to cause the anisotropic material to become slightly tacky. In the case of using a thermosetting resin containing conductive particles, the particles are trapped between prominent points, such as electrodes, between the substrate and the component, thereby creating an electrical connection therebetween. Other particles are insulated by the thermosetting resin. In some cases this mounting step is skipped and the two sides go directly to the bonding portion of the process. In high volume manufacturing, however, this would lead to inefficiencies in the manufacturing process, so direct bonding is usually done only in the lab or in small scale manufacturing.\nBonding is the third and final process required to complete an ACF assembly. In the first two processes the temperatures can range from ambient to 100 °C, with the heat applied for 1 second or less. For bonding, the amount of thermal energy required is higher due to the need to first flow the adhesive and allow the two sides to come together into electrical contact, and then to cure the adhesive and create a lasting reliable bond. The temperatures, times, and pressure required for these processes can vary as shown in the following table.\nTable 1: Common ACF Assembly Conditions\n▲ Pressures for flex assemblies (FOG, FOB, FOF) are measured across the entire area under the bondhead.\n※Pressures for chip assemblies (COG, COF) are calculated on the cumulative surface area of the bumps on the chip.", "Engineering,_Manufacturing": 0.9997608066, "qwen": "Yes"}
{"id": "10282619", "revid": "7583140", "url": "https://en.wikipedia.org/wiki?curid=10282619", "title": "List of electronics brands", "text": "This list of electronics brands is specialized as the list of brands of companies that provide electronics equipment.\nCategories.\nElectronics equipment includes the following categories (abbreviations used in parentheses):\nOther indications:", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "10284712", "revid": "6727347", "url": "https://en.wikipedia.org/wiki?curid=10284712", "title": "Hirose U.FL", "text": "Hirose U.FL, I-PEX MHF I, AMC or UMCC is a miniature RF connector for high-frequency signals up to 6 GHz manufactured by Hirose Electric Group, I-PEX, and others.\nU.FL connectors are commonly used in applications where space is of critical concern, such as in smartphones and Laptop WiFi cards. U.FL connectors are commonly used inside laptops and embedded systems to connect the Wi-Fi antenna to a Mini PCI, Mini PCIe or M.2 WiFi card. Another common use is connecting GPS antennas.\nFemale U.FL connectors are not designed with reconnection in mind, and they are only rated for a few reconnects (approximately 30 mating cycles) before replacement is needed. The female U.FL connectors are generally not sold separately, but rather as part of a pigtail with a high-quality 1.32 mm doubly shielded cable, which allows for a low-loss connection, insulated with fluorinated resin.\nThe male connectors are surface-mounted (SMT) and soldered directly to the printed circuit board (PCB). They are designed to have a characteristic impedance of 50 ohms. The mated connection is only 2.5 mm high and takes as little as 9 mm2 (3.0 × 3.1 mm2) of board space.\nMuch like many other electronic components, Hirose U.FL connectors were protected by patents and trademarks. However, compatible third party connectors are available under many other names, e.g. Sunridge MCB.\nHirose W.FL.\nThe Hirose W.FL, also known as Amphenol AMMC, is an ultra small RF connector used in handheld electronic products. It is manufactured by Hirose Electric Group and has a frequency range up to 6 GHz. Compared to its predecessor U.FL it occupies even less area (2.0 mm diameter) and height (1.4 mm).\nLike U.FL, W.FL also has many more names assigned to it by those producing compatible connectors.", "Engineering,_Manufacturing": 0.9986382723, "qwen": "Yes"}
{"id": "52444382", "revid": "1006162", "url": "https://en.wikipedia.org/wiki?curid=52444382", "title": "Operations management for services", "text": "Operations management for services has the functional responsibility for producing the services of an organization and providing them directly to its customers. It specifically deals with decisions required by operations managers for simultaneous production and consumption of an intangible product. These decisions concern the process, people, information and the system that produces and delivers the service. It differs from operations management in general, since the processes of service organizations differ from those of manufacturing organizations.\nIn a post-industrial economy, service firms provide most of the GDP and employment. As a result, management of service operations within these service firms is essential for the economy.\nThe services sector treats services as intangible products, service as a customer experience and service as a package of facilitating goods and services. Significant aspects of service as a product are a basis for guiding decisions made by service operations managers. The extent and variety of services industries in which operations managers make decisions provides the context for decision making.\nThe six types of decisions made by operations managers in service organizations are: process, quality management, capacity & scheduling, inventory, service supply chain and information technology.\nDefinition of services.\nThere have been many different definitions of service. Russell and Taylor (2011) state that one of the most pervasive, and earliest definitions is “services are intangible products”. According to this definition, service is something that cannot be manufactured. It can be added after manufacturing (e.g. product repair) or it can stand alone as a service (e.g. dentistry) delivered directly to the customer. This definition has been expanded to include such ideas as “service is a customer experience.” In this case the customer is brought into the definition as the experience the customer receives while “consuming” the service.\nA third definition of service concerns the perceived service as consisting of physical facilitating goods, explicit service and implicit service. In this case the facilitating goods are the buildings and inventory used to provide the service. For example, in a restaurant the facilitating goods are the building and the food. The explicit service is what is perceived as the observable part of the service (the sights, sounds and look of the service). In a restaurant the explicit service is the time spent waiting for service, the appearance of the facility and the employees, and the ambience of sounds and light and the decor. The implicit service is the feeling of safety, psychological well-being and happiness associated with the service.\nComparison of manufacturing and services.\nAccording to Fitzsimmons, Fitzsimmons and Bordoloi (2014) differences between manufactured goods and services are as follows:\nThese four comparisons indicate how management of service operations are quite different from manufacturing regarding such issues as capacity requirements (highly variable), quality assurance (hard to quantify), location of facilities (dispersed), and interaction with the customer during delivery of the service (product and process design).\nService industries.\nIndustries have been defined by economists as consisting of four parts: Agriculture, Mining and Construction, Manufacturing, and Service. Services have existed for centuries. Early service was associated with servants. Servants were hired to do tasks that the wealthy did not want to do for themselves (e.g. cleaning the house, cooking, and washing clothes). Later, services became more organized and were provided to the general public.\nIn 1900 the U.S. service industry (e.g., consisting of banks, professional services, schools and general stores) was fragmented, except for the railroads and communications. Services were largely local in nature and owned by entrepreneurs and families. The U.S. in 1900 had 31% employment in services, 31% in manufacturing and 38% in agriculture.\nServices have now evolved to become the dominant form of employment in industrialized economies. Much of the world has progressed, or is progressing, from agricultural to industrial and now post-industrial economies. The U.S. Bureau of Labor Statistics provides a table of the employment of the 151 million people by industry in the U.S. for 2014.\nSource:\nThe table shows that service industries now constitute 83% of employment in the U.S., while agriculture, mining, construction and manufacturing are only 17% of the total employment. Service industries are very diversified ranging from those that are highly capital intensive (e.g. banks, utilities, airlines, and hospitals) to those that are highly people intensive (e.g. retail, wholesale, and professional services). In capital intensive services the focus is more on technology and automation, while in people intensive services the focus is more on managing service employees that deliver the service.\nService and manufacturing industries are highly interrelated. Manufacturing provides tangible facilitating goods needed to provide services; and services such as banking, accounting and information systems provide important service inputs to manufacturing. Manufacturing companies have an opportunity to provide more services along with their products. This can be an important point of product differentiation, leading to increased sales and profitability for manufacturers.\nWhile the focus is often on service industries, there is an opportunity to apply service principles to internal services in an organization, particularly by focusing on internal customers. Internal services such as payroll, accounting, legal, information systems or human resources often have not identified their internal customers, nor do they understand their customer needs. Service ideas ranging from process design, to lean systems, quality management, capacity and scheduling have been widely applied to internal services.\nService design.\nService design begins with a business strategy and service strategy. The business strategy defines what business the firm is in, for example, the Walt Disney Company defines its business strategy \"as making people happy.\" A business strategy also defines the target market, competitors, financial goals, new products, how the company competes, and perhaps some aspects of operations.\nFollowing from the business strategy is the service concept. It must provide the rationale for why the customer should buy the service offered. It defines what the customer is receiving and what the service organization is providing. The service concept includes:\nManagers can use the service concept to create organizational alignment and develop new services. It provides a means for describing the service business from an operations point of view.\nAfter defining the service concept, operations can proceed to define the service-product bundle (or service package) for the organization. It consists of five parts: service facility, facilitating goods, information, explicit service and implicit services. It is important to carefully define each of these elements so that operations can subsequently design and manage a service operation. The service-product bundle must come first before operations decisions.\nAn example of service-product bundle characteristics follows:\nOnce the service package is specified, operations is ready to make decisions concerning the process, quality, capacity, inventory, supply chain and information systems. These are the six decision responsibilities of service operations. Other decision responsibilities such as market choice, product positioning, pricing, advertising and channels belong to the marketing function. Finance takes care of financial reporting, investments, capitalization, and profitability.\nOperations decisions.\nProcess decisions.\nProcess decisions include the physical processes and the people that deliver the services to the customer. A service process consists of all the routines, tasks and steps that are used to deliver service to customers along with the jobs and training for service employees. There are many ways to organize a process to provide customer service in an effective and efficient manner to deliver the service-product bundle. Several ideas have been advanced on how to design a service process.\nCustomer contact.\nDesign of a service system must consider the degree of customer contact. The importance of customer contact was first noted by Chase and Tansik (1983). They argued that high customer contact processes should be designed and managed differently from low-contact processes. High-contact processes have the customer in the system while providing the service. This can lead to difficulties in standardizing the service or inefficiencies when the customer makes demands or expects unique services. On the other hand, high-contact also provides the possibility of self-service where customers provide part of the service themselves (e.g. filing your own gas tank, or packing your own groceries). Low-contact services are performed away from the customer in what is often called \"the back room.\" In this case, the service process can be more standardized and efficient (e.g. check clearing in a bank, filling orders in a warehouse) since the customer is not in the system to request preferences, customization or changes. Low-contact services can be managed more like manufacturing, high-contact services cannot.\nProduction-line approach.\nIn 1972 Levitt introduced the \"production-line approach to service\". He argued that service processes could be made more efficient by standardizing them and automating them like manufacturing. He gave the example of McDonald's that has standardized both the services at the front counter and the backroom for producing the food. They have limited the menu, simplified the jobs, trained the managers (at \"Hamburger U\"), automated production and instituted standards for courtesy, cleanliness, speed and quality. As a result, McDonald's has become a model for other service processes which have been designed for high efficiency, not only in fast food, but in many other services. At the same time, it leaves open the option for more customized and flexible services for customers who are willing to pay more for \"better\" or more personalized service. While these services are less efficient, they cater more to unique customer's needs.\nService process matrices.\nMany different service process matrices have been proposed for explaining the relationship between service products that are selected and corresponding processes. One of these is shown below.\nThe Service Delivery System Matrix by Collier and Meyer (1998) illustrates the various types of routings used for service process depending on the amount of customization and customer involvement in the process. With high levels of customization and customer involvement, there are many pathways and jumbled flows for service. As a result, the service delivery of Customer-Routed services is less efficient than Co-routed or Provider-Routed processes that have less customization and less customer involvement. Process that should be used for each combination of customization and customer involvement are shown on the diagonal of this matrix.\nSelf-service.\nSelf-service is in wide use. For example, in the 1960s gas station attendants came out and pumped your gas, cleaned your windshield and even checked your oil. Fast food is famous for self-service, since customers have been trained to order their own food, pay immediately, find a table, and clean up the trash. ATM's have replaced many traditional tellers and online banking provides even more self-service.\nWhen self-service is accepted by the customer, it can reduce costs and even provide better service in the customer's eyes—faster service with less hassle. Self-service falls in the provider-routed or co-routed part of the Service delivery matrix. Services that were previously customer-routed have been moved down the diagonal to be more efficient and accepted by customers.\nService Blueprint\nThe service blueprint is a way to describe the flow of a customer through a service operation from the start to the finish, along with the actions provided by the service providers both in interaction with the customer and in the \"back room\" out of sight of the customer. For example, if a customer wishes to purchase a suit, the service blueprint starts with entry to the store, next the customer is greeted by a sales representative, the customer then provides information on his/her needs, the sales representative searches for appropriate suits, one or more suits are selected and tried-on for a fitting, a suit is selected and then alterations are done (which take place away from the customer), the customer pays for the suit and returns later to pick it up. A blueprint flowchart shows every step in the process and can be used to illustrate the process and improve it.\nLean thinking.\nIf lean thinking is applied, the time taken for each step in a service blueprint flowchart can be recorded, or a separate value-stream map can be constructed. Then the process can be analyzed for time reductions to reduce waiting and non-value added steps. Changes are made to reduce time and waste in the process. Waste is anything that does not add value to the process including waiting time in line, possibility of more self-service, customer hassle, and defects in service. But, lean thinking also requires attention to the customer and the people providing the service. It is important to apply important principles such as completely solve the customer's problem, don't waste time and provide exactly what the customer requires.\nLeite and Vieira (2015) state that service managers must realize that the customer will be happy if the service provided meets or exceeds expectations. Also the interaction between the customer and the people providing the service is essential to achieve satisfied customers. Employee involvement is often emphasized as part of lean thinking to achieve high levels of commitment by service employees.\nQueuing.\nQueuing is an analytic method for determining waiting time when customers must wait in line to get service. The length of the queue and waiting time can be calculated based on the arrival rate, service rate, number of servers and type of lines. There are many formulas for various types of queuing theory problems. The formulas generally predict that the \"average\" service time must be significantly less than the \"average\" time between arrivals when there is randomness in arrivals and/or service time. The reason for this is that a long line will build up when randomness of arrivals occurs faster than the average and service times are longer than the average. If the distributions of arrival times and service times are known, formulas are available for calculating the exact waiting times and line lengths for many different queuing configurations of servers, types of lines, server distributions and arrival distributions.\nService-profit chain.\nHeskett, Sasser and Schlensinger (1997) proposed the service-profit chain as a way to design service processes. The service-profit chain links various aspects and tasks required to deliver superior service and profits. It starts with a high level of internal quality leading to employee satisfaction and productivity to deliver superior external customer service leading to customer satisfaction, customer loyalty and finally high revenues and profits.\n \nEvery link in this chain is important and the linkage between the service providers and the customer is essential in service operations. The service manager should not break any of the links in order to receive the results of high probability and growth.\nQuality management.\nSERVQUAL measurement.\nUsing the customer experience approach, a questionnaire called SERVQUAL has been developed to measure the customer's perception of the service. The dimensions of SERVQUAL are designed to measure the customer experience in both explicit and implicit measures. The dimensions are:\nA debate about SERVQUAL has ensued about whether customer service should be measured in absolute terms or relative to expectations. Some argue that if high levels on all SERVQUAL dimensions are provided then the service is high quality. Others argue that ultimately the service result is judged by the customer relative to the customer's expectations and not by the service provider. If customer expectations are low, even low levels on SERVQUAL dimensions provides high quality.\nQuality management approaches.\nQuality management practices for services have much in common with manufacturing, despite the fact that the product is intangible. The following approaches are widely used for quality improvement in both manufacturing and services:\nThese approaches have several things in common. They begin with defining and measuring the customer's needs (e.g. using SERVQUAL). Any service that does not meet a customer's need is considered a defect. Then these approaches seek to reduce defects through statistical methods, cause-and-effect analysis, problem solving teams, and involvement of employees. They focus on improving the processes that underlie production of the service.\nIn addition to intangibility, there are two approaches about quality that are unique to service operations management.\nService recovery.\nFor manufactured products, quality problems are handled through warranties, returns and repair after the product is delivered. In high contact services there is no time to fix quality problems later; they must be handled by service recovery as the service is delivered. For example, if soup is spilled on the customer in a restaurant, the waiter might apologize, offer to pay to have the suit cleaned and provide a free meal. If a hotel room is not ready when promised, the staff could apologize, offer to store the customer's luggage or provide an upgraded room. Service recovery is intended to fix the problem on the spot and go even further to offer the customer some form of consolation and compensation. The objective is to make the customer satisfied with the situation, even though there was a service failure.\nService guarantee.\nA service guarantee is similar to a manufacturing guarantee, except the service product cannot be returned. A service guarantee provides a specific monetary reward for failure of service delivery. Some examples are:\nService guarantees serve to assure the customer of quality and they provide a way for the employees to know the cost of service failure.\nCapacity and scheduling.\nForecasting.\nForecasting demand is a prerequisite for managing capacity and scheduling. Forecasting demand often uses big data to predict customer behavior. The data comes from scanners at retail locations or other service locations. In some cases traditional time series methods are also used to predict trends and seasonality. Future demand is forecasted based on past demand patterns. Many of the same time-series and statistical methods for forecasting are used for manufacturing or service operations.\nCapacity planning.\nCapacity planning is quite different between manufacturing and services given that service cannot be stored or shipped to another location. As a result, location of services is very dispersed to be near the customer. Customers are only willing to travel short distances to receive most services. Exceptions are health care when the illness requires a specialist, airline transportation when the service is to move the customer, and other services where local expertise is not available. Aside from these exceptions, location analysis depends on the \"drawing power\" based on the distance a customer is willing to travel to a service site relative to competitive offerings and locations. The drawing power of a site for a particular customer is high if the site is close by and provides the required service. High drawing power is related to high sales and profits. This is very different from manufacturing locations which depend on the cost of building a factory plus the cost of transporting the goods to the customers. Manufacturing plants are located on the basis of low costs rather than high revenues and profits for services.\nA second difference from manufacturing is planning for capacity utilization once a facility is built. Since the product cannot be stored in inventory and sold later, service capacity is perishable and must meet peak demand at any point in time. There are two ways to deal with this problem. First, management can attempt to reduce peak demand and level it over time by the following actions.\nManagement can also use various methods to manage the supply of services including:\nWhile some of these same mechanisms are used in manufacturing, they are much more crucial in service operations.\nRevenue management.\nRevenue management is unique to services, since capacity is perishable. This applies to the airline industry. When the plane leaves the runway, empty seats generate no revenue, but the cost of the flight is almost the same. As a result, mathematical models have been formulated to allocate capacity at various prices and times as the flight is booked in advance. Initially, a certain number of seats are reserved for first class, coach, premium coach and various other categories. Based on the elasticity of demand, seats prices are lowered at the last minute in order to fill empty seats and maximize the revenue of the flight. Similar models have also been developed for revenue management in hotels, where the capacity is also perishable.\nScheduling.\nScheduling has some differences between manufacturing and service. In manufacturing, jobs are scheduled through a factory to sequence them in the best order to meet due dates and reduce costs. In services, it is customers who are being scheduled. As a result, waiting time becomes much more critical. While manufacturing orders don't mind waiting in line or waiting in inventory, real customer's do mind. Some of the scheduling applications for services are: scheduling of patients to operating rooms in hospitals and scheduling students to classes. Many scheduling problems have been solved by using operations research methods to optimize the schedule.\nInventory.\nInventory management and control is needed in service operations with facilitating goods. Almost every service uses some amount of facilitating goods. The presence of facilitating goods is critical in retail and wholesale operations but these operations don't manufacture anything, rather they distribute goods and provide service while doing it. One difference from manufacturing inventories is that services use only finished goods, while manufacturing has finished goods, work-in-process and raw-materials inventories. As a result, manufacturing uses a Materials Requirements Planning System, while services do not. Services use Replenishment inventory control systems such as order-point and periodic-review systems.\nService supply chains.\nSupply chains for service operations are critical to supply facilitating goods. A typical hospital supply chain is an example. A hospital will use many goods from suppliers to construct and furnish the building. During day-to-day operation of the hospital, inventories of supplies will be held for the operating rooms and throughout the building. The pharmacy will hold drugs and the kitchen will need supplies of food. The supply chain of facilitating goods in hospitals is extensive.\nPurchasing controls a large part of costs in retail and wholesale operations, approximately 75% of all costs are for purchased goods. Outside of retail and wholesale operations, facilitating goods are a much smaller part of total costs reaching a low of 10% for most professional services. Both manufacturing and service organizations purchase goods and must deal with outsourcing and offshoring, as well as, domestic products.\nService inputs are critical for manufacturing including capital from banks, energy, information systems and human resources. Services are part of the manufacturing supply chain, just like the physical inputs of products from other manufacturing companies.\nBoth manufacturing and service operations can purchase services from outside the organization. Internal business services such as accounting, legal, human resources, call centers, and information systems may be outsourced in part or entirely. Some of these services can also be purchased from offshore. Logistics services may be outsourced to Third Party Logistics (3PL) providers. These services include transportation, warehousing, order fulfillment, returns and tariffs.\nInformation technology.\nThe Internet and information technology has dramatically changed the delivery of services. Some of the major changes are as follows:\nManagement science and operations research (MSOR).\nAnalysis using MSOR methods has been extensive in services. Areas where they have been heavily applied are in inventory, capacity, scheduling, queuing and forecasting. With the advent of the Internet, information systems, big data and analytics, there are many opportunities to make improvements in decision making for services. The analytic techniques include statistics, management science and operations research.", "Engineering,_Manufacturing": 0.9993206263, "qwen": "Yes"}
{"id": "30339203", "revid": "29495429", "url": "https://en.wikipedia.org/wiki?curid=30339203", "title": "CaseStack", "text": "CaseStack is an American company that provides supply chain management (SCM) services, including warehousing, transportation, and supply chain management software (SCMS) to consumer packaged goods companies (CPGs). It uses a proprietary software as a service platform for its collaborative retailer consolidation programs. CaseStack has been recognized in Food Logistics' Top 85 3PL Providers, Global Logistics & Supply Chain Strategies 100 Great Supply Chain Partners and Inbound Logistics' Top 100 3PL Providers.\nHistory.\nCaseStack was founded in 1999 by former Procter & Gamble executive, Dan Sanker. CaseStack began with a headquarters based in Santa Monica, California, and added another in Fayetteville, Arkansas in 2007.\nCaseStack offers three distinct technology editions for logistics services: a Transportation Edition for clients who outsource only transportation services; a Logistics Edition that includes warehousing; and an Enterprise Edition for clients who integrate with their enterprise-wide systems.\nIn April 2018, CaseStack announced a strategic partnership with ShipChain, a blockchain based solution provider for the transport and logistics industry.\nIn November 2018, CaseStack announced it was being acquired as a division of Hub Group, a transportation management company.\nIn December 2018, Hub Group completed the acquisition of CaseStack.", "Engineering,_Manufacturing": 0.9998912811, "qwen": "Yes"}
{"id": "1079294", "revid": "14548726", "url": "https://en.wikipedia.org/wiki?curid=1079294", "title": "Amoskeag Locomotive Works", "text": "The Amoskeag Locomotive Works, in Manchester, New Hampshire, built steam locomotives at the dawn of the railroad era in the United States. The locomotive works operated as a division of the Amoskeag Manufacturing Company between 1848 and 1859.\nBesides building locomotives for railroad use, Amoskeag also built steam fire engines until 1876. A steam-driven self-propelled appliance was made by Amoskeag was used to fight the Great Boston Fire of 1872. Amoskeag fire engines served as the initial fleet for the New York City Fire Department and the first Los Angeles Fire Department fire company. The Firefighters Museum in Yarmouth, Nova Scotia, has an 1863 Amoskeag fire engine.\nCompany history.\nThe locomotive manufacturing operations began within a new machine shop built for the Amoskeag Manufacturing Company. The shop opened in 1848, and the first locomotive was built there in 1849. In 1856 the shop built 60 locomotives.\nIn 1859 Amoskeag Manufacturing sold the locomotive business to Manchester Locomotive Works, of which Oliver W. Bayley and Aretas Blood were principals. Amoskeag Manufacturing sold the fire engine business to the Manchester Locomotive Works in 1876.", "Engineering,_Manufacturing": 1.0000076294, "qwen": "Yes"}
{"id": "71386758", "revid": "3022076", "url": "https://en.wikipedia.org/wiki?curid=71386758", "title": "Toyota Motor Manufacturing Missouri", "text": "Toyota Motor Manufacturing Missouri (TMMMO) is a manufacturing plant in Troy, Missouri that focuses on building cylinder heads for straight-four engines built by Toyota. It is a subsidiary of Toyota Motor North America, itself a subsidiary of Toyota Motor Corporation of Japan.\nThe company traces its roots back to 1912 when Jesse Bodine founded the Bodine Pattern Company in St. Louis. Bodine produced mold castings for various customers including automotive. When Toyota started to expand its manufacturing presence in North America in the late 1980s turned to Bodine to supply aluminum parts. In 1990, the automaker purchased the company, renaming it Bodine Aluminum.\nIn 1991, Toyota broke ground on an additional plant in Troy, Missouri that would open in 1993. Bodine Aluminum opened a plant in Jackson, Tennessee in 2003, and closed its St. Louis plant in December 2018.\nIn 2020, the company's name changed from Bodine Aluminum to Toyota Motor Manufacturing Missouri, while the Jackson plant became Toyota Motor Manufacturing Tennessee.\nToyota Motor Manufacturing Missouri has the ability to build more than 3 million cylinder heads annually on three production lines.\nThe plant is located next to Missouri Smelting Technology (MOST), an aluminum recycler that provides raw material to TMMMO. MOST is a subsidiary of Toyota Tsusho, another company in Japan's Toyota Group.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "71386795", "revid": "3022076", "url": "https://en.wikipedia.org/wiki?curid=71386795", "title": "Toyota Motor Manufacturing Tennessee", "text": "Toyota Motor Manufacturing Tennessee (TMMTN) is a manufacturing plant located in Jackson, Tennessee that focuses on mold casting aluminum engine blocks and hybrid transaxle casings. It is a subsidiary of Toyota Motor North America, itself a subsidiary of Toyota Motor Corporation of Japan.\nThe plant was established in 2003 as part of Toyota's Bodine Aluminum division, which also operates a plant in Troy, Missouri.\nIn 2020, the company's name changed from Bodine Aluminum to Toyota Motor Manufacturing Tennessee. The company still shares leadership with the Missouri plant, now renamed Toyota Motor Manufacturing Missouri.\nToyota Motor Manufacturing Tennessee has the ability to build more than 2 million engine blocks annually.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "71424701", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=71424701", "title": "Cooper Mark X", "text": "The Cooper Mk.X, and its evolutions, the Mk.XI, the Mk.XII, and the Mk.XIII, are open-wheel Formula Three race cars, designed, developed, and built by British manufacturer Cooper in 1956 (with production continuing through 1959). It was virtually identical in design to the previous Mk.IX. The internal designation, dubbed the T42, was powered by a JA Prestwich Industries (JAP) single-cylinder engine, and featured a singular brake disk at the rear of the car, flatter springs to mitigate ground clearance, altered and adjusted center spring mountings, and reworked engine mounts. The second version featured an elongated chassis and body, and a larger and more powerful OHV V-2 engine. Weight and chassis dimensions were essentially identical to the previous model.", "Engineering,_Manufacturing": 0.9996691942, "qwen": "Yes"}
{"id": "22878106", "revid": "23914831", "url": "https://en.wikipedia.org/wiki?curid=22878106", "title": "Roller burnishing", "text": "Roller burnishing is a surface finishing technique where hardened rollers cold work surface imperfections to reduce surface roughness. Roller burnishing differs from abrasive surface finishing techniques in that material is displaced rather than removed. The tooling typically consists of a hardened sphere or cylindrical roller. The tooling is pressed into the surface of the part while it is rotated (in some applications, the tools are rotated instead of the part). The burnishing tool rolls against the surface of the part at a constant speed, producing a very consistent finish across the part. A surface finish of less than Ra 0.1 µm is achievable with roller burnishing. A side effect is that the outer surface of the part is work hardened.\nRoller burnishing is used in the production of some crankshafts. A dual roller (cylindrical) tool is moved into the thrust bearing journal of a crankshaft, while the crankshaft is spinning the tool is indexed (so each roller is perpendicular to the thrust surface while backing each other up) deforming the surfaces. So the diameters of each roller added together (compensated for elastic deformation) equals the finish dimension of the thrust bearing.\nIn deep hole machining, a roller burnishing tool is often combined with skiving knives on the same tool. The skiving knives pass first, scraping the inside layer of metal, followed by the burnishing rollers, which cold work the tube to create a mirror surface finish. Skive-burnishing is often used in hydraulic cylinder applications. This process can happen on a deep hole drilling machine or a dedicated skiving machine.\nReferences.\nExperimental investigation of mild steel components by Roller Burnishing process and mechanical properties by Taguchi method. https://www.irjet.net/archives/V6/i2/IRJET-V6I2398.pdf", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "22878791", "revid": "43558034", "url": "https://en.wikipedia.org/wiki?curid=22878791", "title": "Supplier risk management", "text": "Supplier risk management (SRM) is an evolving discipline in operations management for manufacturers, retailers, financial services companies and government agencies where an organization is dependent on suppliers to achieve business objectives.\nThe complexity and globally outsourced nature of modern supply chains, combined with the practice of optimization techniques such as lean and just-in-time manufacturing in order to improve efficiency, has increased supply chain vulnerabilities to even minor supply disruptions. While these models have allowed companies to reduce overall costs and expand quickly into new markets, they also expose the company to the risk of a supplier bankruptcy, closing operations, data breach or being acquired. Among the several types of supply disruptions, most severe are those that have a relatively low probability of occurrence with a very high severity of impact when they do occur. While such risks cannot be eliminated, however, its severity can be reduced.\nObjectives.\nTo overcome these challenges, companies mitigate supply chain interruptions and reduce risk with strategies and tactics that address supplier-centric risk at multiple stages in the relationship:\nSupplier risk in recession and recovery.\nIn 2008–2009, manufacturers experienced the startling speed at which suppliers can move from stability to shutting down operations. The devastating impact of a crucial supplier failure has moved risk management from add-on service to mission-critical. With a new focus on risk management, manufacturers have seen value whether the economy is stagnant or thriving.\nWith a transparent, accessible and comprehensive set of supplier information, manufacturers have been able to monitor suppliers for behavioral changes which contribute to overall stability, including: \nChanges in any of these conditions can be defined as parameters for raising an alert. For example, a financially stable supplier may in fact be about to lose it CEO to retirement – which may cause issues within the management team. Early visibility into that change gives the manufacturer time to ensure it does not affect customers negatively.\nBased on the criticality of the supplier and the nature of the alert received, the manufacturer can then choose to take necessary action, such as calling or visiting the supplier, increasing monitoring, or moving towards terminating the relationship with the supplier and finding a replacement.\nBenefits.\nReducing supplier risk can: ", "Engineering,_Manufacturing": 0.9989789724, "qwen": "Yes"}
{"id": "383131", "revid": "23914831", "url": "https://en.wikipedia.org/wiki?curid=383131", "title": "Flip chip", "text": "Flip chip, also known as controlled collapse chip connection or its abbreviation, C4, is a method for interconnecting dies such as semiconductor devices, IC chips, integrated passive devices and microelectromechanical systems (MEMS), to external circuitry with solder bumps that have been deposited onto the chip pads. The technique was developed by General Electric's Light Military Electronics Department, Utica, New York. The solder bumps are deposited on the chip pads on the top side of the wafer during the final wafer processing step. In order to mount the chip to external circuitry (e.g., a circuit board or another chip or wafer), it is flipped over so that its top side faces down, and aligned so that its pads align with matching pads on the external circuit, and then the solder is reflowed to complete the interconnect. This is in contrast to wire bonding, in which the chip is mounted upright and fine wires are welded onto the chip pads and lead frame contacts to interconnect the chip pads to external circuitry.\nComparison of mounting technologies.\nWire bonding/thermosonic bonding.\nIn typical semiconductor fabrication systems, chips are built up in large numbers on a single large wafer of semiconductor material, typically silicon. The individual chips are patterned with small pads of metal near their edges that serve as the connections to an eventual mechanical carrier. The chips are then cut out of the wafer and attached to their carriers, typically via wire bonding such as thermosonic bonding. These wires eventually lead to pins on the outside of the carriers, which are attached to the rest of the circuitry making up the electronic system.\nFlip chip.\nProcessing a flip chip is similar to conventional IC fabrication, with a few additional steps. Near the end of the manufacturing process, the attachment pads are metalized to make them more receptive to solder. This typically consists of several treatments. A small dot of solder is then deposited on each metalized pad. The chips are then cut out of the wafer as normal.\nTo attach the flip chip into a circuit, the chip is inverted to bring the solder dots down onto connectors on the underlying electronics or circuit board. The solder is then re-melted to produce an electrical connection, typically using a thermosonic bonding or alternatively reflow solder process.\nThis also leaves a small space between the chip's circuitry and the underlying mounting. In many cases an electrically-insulating adhesive is then \"underfilled\" to provide a stronger mechanical connection, provide a heat bridge, and to ensure the solder joints are not stressed due to differential heating of the chip and the rest of the system.\nThe underfill distributes the thermal expansion mismatch between the chip and the board, preventing stress concentration in the solder joints which would lead to premature failure.\nIn 2008, High-speed mounting methods evolved through a cooperation between Reel Service Ltd. and Siemens AG in the development of a high speed mounting tape known as 'MicroTape'. By adding a tape-and-reel process into the assembly methodology, placement at high speed is possible, achieving a 99.90% pick rate and a placement rate of 21,000 cph (components per hour), using standard PCB assembly equipment.\nTape-automated bonding.\nTape-automated bonding (TAB) was developed for connecting dies with thermocompression or thermosonic bonding to a flexible substrate including from one to three conductive layers. Also with TAB it is possible to connect die pins all at the same time as with the soldering based flip chip mounting. Originally TAB could produce finer pitch interconnections compared to flip chip, but with the development of the flip chip this advantage has diminished and has kept TAB to be a specialized interconnection technique of display drivers or similar requiring specific TAB compliant roll-to-roll (R2R, reel-to-reel) like assembly system.\nAdvantages.\nThe resulting completed flip chip assembly is much smaller than a traditional carrier-based system; the chip sits directly on the circuit board, and is much smaller than the carrier both in area and height. The short wires greatly reduce inductance, allowing higher-speed signals, and also conduct heat better.\nDisadvantages.\nFlip chips have several disadvantages.\nThe lack of a carrier means they are not suitable for easy replacement, or unaided manual installation. They also require very flat mounting surfaces, which is not always easy to arrange, or sometimes difficult to maintain as the boards heat and cool. This limits the maximum device size.\nAlso, the short connections are very stiff, so the thermal expansion of the chip must be matched to the supporting board or the connections can crack. The underfill material acts as an intermediate between the difference in CTE of the chip and board.\nHistory.\nThe process was originally introduced commercially by IBM in the 1960s for individual transistors and diodes packaged for use in their mainframe systems.\nAlternatives.\nSince the flip chip's introduction a number of alternatives to the solder bumps have been introduced, including gold balls or molded studs, electrically conductive polymer and the \"plated bump\" process that \"removes\" an insulating plating by chemical means. Flip chips have recently gained popularity among manufacturers of cell phones and other small electronics where the size savings are valuable.", "Engineering,_Manufacturing": 0.9998005033, "qwen": "Yes"}
{"id": "57397077", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=57397077", "title": "2018–19 UEFA Europa League qualifying phase and play-off round (Main Path)", "text": "This page summarises the Main Path matches of 2018–19 UEFA Europa League qualifying phase and play-off round.\nTimes are CEST , as listed by UEFA (local times, if different, are in parentheses).\nPreliminary round.\nSummary.\n\nMatches.\n\"Prishtina won 6–1 on aggregate.\"\n\"Gżira United won 4–1 on aggregate.\"\n\"Engordany won 3–2 on aggregate.\"\n\"2–2 on aggregate. B36 Tórshavn won 4–2 on penalties.\"\n\"KÍ Klaksvík won 3–2 on aggregate.\"\n\"Tre Fiori won 3–1 on aggregate.\"\n\"Trakai won 2–1 on aggregate.\"\nFirst qualifying round.\nSummary.\n\nNotes\n\nMatches.\n\"Stjarnan won 3–1 on aggregate.\"\n\"Slavia Sofia won 3–1 on aggregate.\"\n\"Žalgiris won 3–2 on aggregate.\"\n\"0–0 on aggregate. Fola Esch won 5–4 on penalties.\"\n\"Molde won 6–3 on aggregate.\"\n\"DAC Dunajská Streda won 3–2 on aggregate.\"\n\"Apollon Limassol won 2–1 on aggregate.\"\n\"3–3 on aggregate. Domžale won on away goals.\"\n\"Rangers won 2–0 on aggregate.\"\n\"Progrès Niederkorn won 2–1 on aggregate.\"\n\"Viitorul Constanța won 2–0 on aggregate.\"\n\"Tobol won 3–0 on aggregate.\"\n\"Maribor won 3–0 on aggregate.\"\n\"Újpest won 5–3 on aggregate.\"\n\"Trenčín won 3–1 on aggregate.\"\n\"Dinamo Minsk won 3–2 on aggregate.\"\n\"B36 Tórshavn won 2–1 on aggregate.\"\n\"Górnik Zabrze won 2–1 on aggregate.\"\n\"Spartak Subotica won 3–1 on aggregate.\"\n\"Pyunik won 3–0 on aggregate.\"\n\"AIK won 2–1 on aggregate.\"\n\"Shakhtyor Soligorsk won 5–1 on aggregate.\"\n\"FH won 3–0 on aggregate.\"\n\"Ventspils won 8–3 on aggregate.\"\n\"Nordsjælland won 3–1 on aggregate.\"\n\"Sarajevo won 5–1 on aggregate.\"\n\"Kairat won 10–1 on aggregate\"\n\"Osijek won 3–2 on aggregate.\"\n\"2–2 on aggregate. Laçi won on away goals.\n\"Maccabi Tel Aviv won 2–1 on aggregate.\"\n\"Balzan won 5–3 on aggregate.\"\n\"Honvéd won 5–2 on aggregate.\"\n\"Partizan won 6–0 on aggregate.\"\n\"1–1 on aggregate. CSKA Sofia won 5–3 on penalties.\"\n\"Slovan Bratislava won 9–2 on aggregate.\"\n\"Radnički Niš won 5–0 on aggregate.\"\n\"Lech Poznań won 3–2 on aggregate.\"\n\"Chikhura Sachkhere won 2–1 on aggregate.\"\n\"3–3 on aggregate. Vaduz won on away goals.\"\n\"Željezničar won 5–1 on aggregate.\"\n\"Trakai won 1–0 on aggregate.\"\n\"Hibernian won 12–5 on aggregate.\"\n\"Rudar Velenje won 10–0 on aggregate.\"\n\"Dundalk won 3–1 on aggregate.\"\n\"Sarpsborg 08 won 6–0 on aggregate.\"\n\"Copenhagen won 2–1 on aggregate.\"\n\"BK Häcken won 4–2 on aggregate.\"\nSecond qualifying round.\nSummary.\n\n\nNotes\n\nMatches.\n\"Molde won 5–0 on aggregate.\"\n\"Atalanta won 10–2 on aggregate.\"\n\"Žalgiris won 2–1 on aggregate.\"\n\"Kairat won 3–2 on aggregate.\"\n\"Burnley won 4–2 on aggregate.\"\n\"Partizan won 2–1 on aggregate.\"\n\"Slovan Bratislava won 4–3 on aggregate.\"\n\"Nordsjælland won 2–0 on aggregate.\"\n\"FCSB won 6–0 on aggregate.\"\n\"Hapoel Haifa won 2–1 on aggregate.\"\n\"AEK Larnaca won 4–0 on aggregate.\"\n\"Trenčín won 5–1 on aggregate.\"\n\"Maccabi Tel Aviv won 4–2 on aggregate.\"\n\"CSKA Sofia won 6–1 on aggregate.\"\n\"Spartak Subotica won 3–2 on aggregate.\"\n\"RB Leipzig won 5–1 on aggregate.\"\n\"Copenhagen won 7–0 on aggregate.\"\n\"1–1 on aggregate. Ufa won on away goals.\"\n\"2–2 on aggregate. Pyunik won on away goals.\"\n\"Jagiellonia Białystok won 5–4 on aggregate.\"\n\"LASK won 6–1 on aggregate.\"\n\"Progrès Niederkorn won 2–1 on aggregate.\"\n\"Rangers won 2–1 on aggregate.\"\n\"Beşiktaş won 8–0 on aggregate.\"\n\"Dinamo Minsk won 7–2 on aggregate.\"\n\"Bordeaux won 3–1 on aggregate.\"\n\"Apollon Limassol won 5–2 on aggregate.\"\n\"Vitesse won 5–3 on aggregate.\"\n\"2–2 on aggregate. Sarpsborg 08 won on away goals.\"\n\"Dynamo Brest won 5–4 on aggregate.\"\n\"Sevilla won 7–1 on aggregate.\"\n\"Lech Poznań won 4–2 on aggregate.\"\n\"Hibernian won 4–3 on aggregate.\"\n\"Maribor won 2–0 on aggregate.\"\n\"Genk won 9–1 on aggregate.\"\n\"Mariupol won 3–2 on aggregate.\"\n\"Hajduk Split won 4–2 on aggregate.\"\nThird qualifying round.\nSummary.\n\n\nMatches.\n\"Maccabi Tel Aviv won 2–1 on aggregate.\"\n\"Zenit Saint Petersburg won 8–5 on aggregate.\"\n\"AEK Larnaca won 7–0 on aggregate.\"\n\"Sarpsborg 08 won 2–1 on aggregate.\"\n\"Burnley won 1–0 on aggregate.\"\n\"3–3 on aggregate. Zorya Luhansk won on away goals.\"\n\"Atalanta won 6–1 on aggregate.\"\n\"Genk won 4–1 on aggregate.\"\n\"Basel won 2–0 on aggregate.\"\n\"Partizan won 5–3 on aggregate.\"\n\"Molde won 3–0 on aggregate.\"\n\"FCSB won 2–1 on aggregate.\"\n\"Sevilla won 6–0 on aggregate.\"\n\"Sigma Olomouc won 4–1 on aggregate.\"\n\"Rapid Wien won 5–2 on aggregate.\"\n\"Bordeaux won 5–2 on aggregate.\"\n\"Copenhagen won 4–2 on aggregate.\"\n\"Olympiacos won 7–1 on aggregate.\"\n\"Rangers won 3–1 on aggregate.\"\n\"Trenčín won 5–1 on aggregate.\"\n\"Gent won 4–1 on aggregate.\"\n\"Brøndby won 4–1 on aggregate.\"\n\"Ufa won 4–3 on aggregate.\"\n\"2–2 on aggregate. Beşiktaş won on away goals.\"\n\"Apollon Limassol won 4–1 on aggregate.\"\n\"RB Leipzig won 4–2 on aggregate.\"\nPlay-off round.\nSummary.\n\n\nNotes\n\nMatches.\n\"Sevilla won 4–0 on aggregate.\"\n\"Sarpsborg 08 won 4–3 on aggregate.\"\n\"Bordeaux won 2–0 on aggregate.\"\n\"Beşiktaş won 4–1 on aggregate.\"\n\"Rapid Wien won 4–3 on aggregate.\"\n\"3–3 on aggregate. Apollon Limassol won on away goals.\" \n\"Rangers won 2–1 on aggregate.\"\n\"0–0 on aggregate. Copenhagen won 4–3 on penalties.\"\n\"Zenit Saint Petersburg won 4–3 on aggregate.\"\n\"AEK Larnaca won 4–1 on aggregate.\"\n\"Genk won 9–4 on aggregate.\"\n\"Olympiacos won 4–2 on aggregate.\"\n\"RB Leipzig won 3–2 on aggregate.\"", "Engineering,_Manufacturing": 0.999294579, "qwen": "Yes"}
{"id": "2838331", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=2838331", "title": "Muda (Japanese term)", "text": " is a Japanese word meaning \"futility\", \"uselessness\", or \"wastefulness\", and is a key concept in lean process thinking such as in the Toyota Production System (TPS), denoting one of three types of deviation from optimal allocation of resources. The other types are known by the Japanese terms \"mura\" (\"unevenness\") and \"muri\" (\"overload\"). Waste in this context refers to the wasting of time or resources rather than wasteful by-products and should not be confused with Waste reduction.\nFrom an end-customer's point of view, value-added work is any activity that produces goods or provides a service for which a customer is willing to pay; \"muda\" is any constraint or impediment that causes waste to occur.\nThere are two types of muda:\nToyota's (Ohno's) Seven Forms of Waste.\nOne of the key steps in lean process and TPS is to identify which activities add value and which do not, then to progressively work to improve or eliminate them.\nTaiichi Ohno, \"father\" of the Toyota Production System, originally identified seven forms of \"muda\" or waste:\nA mnemonic may be useful for remembering the categories of waste, such as TIM WOOD or TIM WOODS.\nTransportation.\nEvery time a product is touched or moved unnecessarily there is a risk that it could be damaged, lost, delayed, etc. as well as being a cost for no added value. Transportation does not add value to the product, i.e. is not a transformation for which the consumer is willing to pay.\nInventory.\nWhether in the form of raw materials, work-in-progress (WIP), or finished goods, represents a capital outlay that cannot yet produce an income. The longer a product sits in one of these states, the more it contributes to waste. The smooth, continuous flow of work through each process ensures excess amounts of inventory are minimized.\nMotion.\nIn contrast to transportation, which refers to damage and transaction costs associated with moving the product, motion refers to the damage and costs inflicted on what creates the product. This can include wear and tear for equipment, repetitive strain injuries for workers or unnecessary downtime.\nWaiting.\nWhenever the product is not in transportation or being processed, it is waiting (typically in a queue). In traditional processes, a large part of an individual product's life is spent waiting to be worked on.\nOverproduction.\nMaking more of a product than is required results in several forms of waste, typically caused by production in large batches. The customer's needs often change over the time it takes to produce a larger batch. Over-production has been described as the worst kind of waste.\nOver processing.\nDoing more to a product than is required by the end-customer results in it taking longer and costing more to produce. This also includes using components that are more precise, complex, expensive or higher quality than absolutely required.\nDefects.\nHaving to discard or rework a product due to earlier defective work or components results in additional cost and delays.\nUnused skills.\nOrganizations often under-utilize the skills their workers have or permit workers to operate in silos so that knowledge is not shared. This was added to the original seven forms of waste, as resolving this waste is a key enabler to resolving the others.\nAlternative forms of waste.\nThe eight forms of waste were developed for Toyota specific processes.\nOther companies and individuals have elucidated or identified other forms of waste. Some examples follow:\nConfusion.\nGeneral uncertainty about the right thing to do, or absence of documented procedures and operating statements.\nSelf-doubt.\nWriter Jim Womack described \"thinking you can't\" as the worst form of waste, quoting Henry Ford's aphorism:\nImplementation.\nShigeo Shingo divides process related activity into Process and Operation. He distinguishes \"Process\", the course of material that is transformed into product, from \"Operation\" which are the actions performed on the material by workers and machines. This distinction is not generally recognized because most people would view the \"Operations\" performed on the raw materials of a product by workers and machines as the \"Process\" by which those raw materials are transformed into the final product. Shingo breaks down the process into four phenomena, Transportation, Inspection, Processing and Delay. He makes this distinction because value is only added during the processing steps in the process not by the transportation, inspection and delay steps. He states that whereas many see Process and Operations in parallel he sees them at right angles (orthogonal) (see Value Stream Mapping). This starkly throws most of the operations into the waste category.\nMany of the TPS/Lean techniques work in a similar way. By planning to reduce manpower, or reduce change-over times, or reduce campaign lengths, or reduce lot sizes, the question of waste comes immediately into focus upon those elements that prevent the plan being implemented. Often it is in the operations' area rather than the process area that muda can be eliminated and remove the blockage to the plan. Tools of many types and methodologies can then be employed on these wastes to reduce or eliminate them.\nThe plan is therefore to build a fast, flexible process where the immediate impact is to reduce waste and therefore costs. By ratcheting the process towards this aim with focused muda reduction to achieve each step, the improvements are 'locked in' and become required for the process to function. Without this intent to build a fast, flexible process there is a significant danger that any improvements achieved will not be sustained because they are \"just\" desirable and can slip back towards old behaviours without the process stopping.", "Engineering,_Manufacturing": 0.9990811348, "qwen": "Yes"}
{"id": "2840555", "revid": "1167963147", "url": "https://en.wikipedia.org/wiki?curid=2840555", "title": "Workforce management", "text": "Workforce management (WFM) is an institutional process that maximizes performance levels and competency for an organization. The process includes all the activities needed to maintain a productive workforce, such as field service management, human resource management, performance and training management, data collection, recruiting, budgeting, forecasting, scheduling and analytics.\nWorkforce management provides a common set of performance-based tools and software to support corporate management, front-line supervisors, store managers and workers across manufacturing, distribution, transportation, and retail operations. It is sometimes referred to as HRM systems, or Workforce asset management, or part of ERP systems.\nDefinition.\nAs workforce management has developed from a traditional approach of staff scheduling to improve time management, it has become more integrated and demand-oriented to optimize the scheduling of staff. Besides the two core aspects of demand-orientation and optimization, workforce management may also incorporate:\nThe starting point is a clear definition of the work required through engineered standards and optimal methods for performing each task as efficiently and safely as possible. Based on this foundation and demand-based forecasts, workers are scheduled, tasks are assigned, performance is measured, feedback is provided and incentives are computed and paid. In addition, online training is provided along with supervisor-based coaching to bring all workers up to required levels of proficiency. Workforce management is a complete approach designed to make workforce as productive as possible, reduce labor costs, and improve customer service.\nField service management.\nWorkforce management also uses the process of field service management in order to have oversight of company's resources not used on company property. Examples include:\nMarket growth.\nIn the 1980s and 1990s, entrepreneurs focused on topics such as supply chain management, production planning systems or enterprise resource planning. As cost pressures have increased, managers have turned their attention to human resources issues. In all personnel-intensive industries, workforce management has become an important strategic element in corporate management. The process has experienced growth in all sectors, including healthcare. The rise of the gig economy has also gone hand in hand with the rise of workforce management preactices.\nMobile workforce management.\nAs our society continues to adopt new technologies such as smartphones and enterprise mobility tools, more companies are allowing employees to become mobile. Mobile workforce management refers to activities used to schedule the employees working outside the company premises. It helps distribute workforce efficiently across various departments in an institution. The need for social distancing imposed by the COVID-19 pandemic has brought about major changes in both employer's and employee's vision of remote work, which will likely have a long-lasting impact on workforce organization and management in the coming years.\nSoftware.\nWorkforce management solutions can be deployed enterprise-wide and through mobile platforms. While special software is commonly used in numerous areas such as ERP (enterprise resource planning), SLM (service lifecycle management), CRM (customer relationship management) and HR (human resources) management, the management of the workforce is often still handled using spreadsheet programs or time recording. This often results in expensive overtime, non-productive idle times, high fluctuation rates, poor customer service and opportunity costs being incurred. By using a software solution for demand-oriented workforce management, planners can optimize staffing by creating schedules that at all times conform to the forecasted requirements. At the same time, a workforce management solution helps users to observe all relevant legislations, local agreements and the contracts of individual employees – including work-life balance guidelines.\nA key aspect of workforce management is scheduling. This is achieved by establishing likely demand by analyzing historical data (such as the number and duration of customer contacts, sales figures, check-out transactions or orders to be handled). Many workforce management systems also offer manual adjustment capabilities. The calculated forecast values are then converted into actual staffing requirements by means of an algorithm that is adjusted to the particular use case. The algorithm itself is based on the work of Erlang though most modern adaptations of workforce management have shifted towards a richer state management, and optimizations to the original idea.\nCurrent and future staffing requirements, short-term peak loads, availabilities, holidays, budget allowances, skills, labour law-related restrictions, as well as wage and contractual terms have to be integrated into the planning process to guarantee optimal staff deployment. In the workforce management process, the integration of employees is an important factor. In several workforce management systems, employees can log in their availability or planned absences and they can bid for specific shifts so long as they have the necessary skills for the activities planned for these shifts.\nDelivery.\nThe three methods of delivery for contact center technologies are on-premises solution, hosted or cloud-based computing.", "Engineering,_Manufacturing": 0.9975357652, "qwen": "Yes"}
{"id": "2036147", "revid": "17927349", "url": "https://en.wikipedia.org/wiki?curid=2036147", "title": "Chip-scale package", "text": "A chip scale package or chip-scale package (CSP) is a type of integrated circuit package.\nOriginally, CSP was the acronym for \"chip-size packaging.\" Since only a few packages are chip size, the meaning of the acronym was adapted to \"chip-scale packaging\". According to IPC's standard J-STD-012, \"Implementation of Flip Chip and Chip Scale Technology\", in order to qualify as chip scale, the package must have an area no greater than 1.2 times that of the die and it must be a single-die, direct surface mountable package. Another criterion that is often applied to qualify these packages as CSPs is their ball pitch should be no more than 1 mm.\nThe concept was first proposed by Junichi Kasai of Fujitsu and Gen Murakami of Hitachi Cable in 1993. The first concept demonstration however came from Mitsubishi Electric.\nThe die may be mounted on an interposer upon which pads or balls are formed, like with flip chip ball grid array (BGA) packaging, or the pads may be etched or printed directly onto the silicon wafer, resulting in a package very close to the size of the silicon die: such a package is called a wafer-level package (WLP) or a wafer-level chip-scale package (WL-CSP). WL-CSP had been in development since 1990s, and several companies begun volume production in early 2000, such as Advanced Semiconductor Engineering (ASE).\nTypes.\nChip scale packages can be classified into the following groups:", "Engineering,_Manufacturing": 0.9998583794, "qwen": "Yes"}
{"id": "891842", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=891842", "title": "Overprinting", "text": "Overprinting refers to the process of printing one colour on top of another in reprographics. This is closely linked to the reprographic technique of 'trapping'. Another use of overprinting is to create a rich black (often regarded as a colour that is \"blacker than black\") by printing black over another dark colour.\nIt is also the term used in the production of envelopes customised to order by printing images (such as logos) and texts (such as slogans) on mass-produced machine-made envelopes; the alternative way of producing such envelopes is to print \"on the flat\" and then cut out the individual shapes and fold them to form the envelopes. However the latter method is generally only economically viable for large print runs offering returns to scale.\nOverprinting also refers to the printing of additional information onto self-adhesive labels and product packaging. \"Best Before\", \"Use By\" dates and batch codes are printed in situ onto product\npackaging as the items are packed. Generally thermal printers, ink jet printers or laser printers are used.", "Engineering,_Manufacturing": 0.9999144077, "qwen": "Yes"}
{"id": "3487282", "revid": "1169870074", "url": "https://en.wikipedia.org/wiki?curid=3487282", "title": "Knife making", "text": "Knife making is the process of manufacturing a knife by any one or a combination of processes: stock removal, forging to shape, welded lamination or investment cast. Typical metals used come from the carbon steel, tool, or stainless steel families. Primitive knives have been made from bronze, copper, brass, iron, obsidian, and flint.\nMaterials for blades.\nDifferent steels are suited to different applications. There is a trade off between hardness, toughness, edge retention, corrosion resistance, and achievable sharpness. Some examples of blade material and their relative trade offs:\nUnusual non-metallic materials may also be used; manufacturing techniques are quite different from metal:\nBlade making process.\nInitial forging.\nThe initial shaping of a knife is traditionally done through forging though stock removal or blanking can be used. Steel can be folded either to form decorative pattern welded steel or to refine raw steel, or as the Japanese call it, tamahagane. Grain size is kept at a minimum as grain growth can happen quite easily if the blade material is overheated.\nIn a mass production environment, or in a well equipped private shop, the blanking process is used to make \"blade blanks.\" This can be achieved by a number of different methods, depending upon the thickness of the material and the alloy content of steel to be cut. Thinner cross section, lower alloy blanks can be stamped from sheet material. Materials that are more difficult to work with, or jobs that require higher production volume, can be accomplished with water jet cutters, lasers or electron beam cutting. These two lend themselves towards larger custom shops. \nKnife makers will sometimes contract out to a shop with the above capabilities to do blanking. For lower production makers, or lower budgets, other methods must suffice. Knife makers may use many different methods to profile a blank. These can include hacksaws, files, belt grinders, wheel grinders, oxy-acetylene torches, CNC mills, bandsaws, or any number of other methods depending on budget.\nGrinding.\nIf no power equipment is available, this can be done with files if the piece of steel has not yet been hardened. Grinding wheels, or small belt sanders are usually what a beginner uses. Well equipped makers usually use a large industrial belt grinder, or a belt grinder made specifically for knife making. The standard size for a knifemakers' belt grinder is a grinder that runs a belt size of 2\" by 72\". Pre-polish grinding on a heat treated blade can be done if the blade is kept cool, to preserve the temper of the steel. Overheating can be observed in the knife by watching for heat discoloration. Some knife makers will use a coolant mist on the grinder to achieve this.\nHeat treatment.\nMethods of heat treatment: atmosphere furnace, molten salt, vacuum furnace, coal (coke) forge, oxy/acetylene torch. Quenching after heat treatment differs according to type of metal and personal preferences. Quenching can be done with oil, animal tallow, water, air, or brine. Most steels will require a specific temperature, soak time, and tempering heat for the different grades.\nBlade finishes.\nThe finish quality of the blade is determined by the Grit of the finishing grind. These can range from a low-shine 280-320 grit finish to a mirror-shine. The high polish shine can be accomplished by buffing with chrome oxide (ex. white chrome, green chrome), hand rubbing with extremely fine wet-or-dry abrasive paper, or with a Japanese water-stone, which has an approximate grit of 10,000-12,000. The knife might also have a different direction in scratch pattern, depending on the method of finishing.\nHandle making process.\nHandle making can be done in several different ways depending on the tang of the knife. Full tang knives usually have handle scales either pinned, riveted, or screwed on to the tang itself while knives without a full tang may be inserted into a solid handle and then attached in one of the previously stated methods. Handle materials can range from natural materials including wood or elk horn to man-made materials like brass, plastic, carbon fiber, polymer or micarta. A knife makers grinder may have additional attachments for making knife handles, such as small diameter contact wheels. ", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "3487414", "revid": "33011235", "url": "https://en.wikipedia.org/wiki?curid=3487414", "title": "Fillet (mechanics)", "text": "In mechanical engineering, a fillet is a rounding of an interior or exterior corner of a part designed in CAD. An interior or exterior corner, with an angle or type of bevel, is called a \"chamfer\". Fillet geometry, when on an interior corner is a line of concave function, whereas a fillet on an exterior corner is a line of convex function (in these cases, fillets are typically referred to as rounds). Fillets commonly appear on welded, soldered, or brazed joints.\nDepending on a geometric modelling kernel different CAD software products may provide different fillet functionality. Usually fillets can be quickly designed onto parts using 3D solid modeling engineering by picking edges of interest and invoking the function. Smooth edges connecting two simple flat features are generally simple for a computer to create and fast for a human user to specify. Once these features are included in the CAD design of a part, they are often manufactured automatically using computer-numerical control.\nTerminology.\nDifferent design packages use different names for the same operations.\nOther 3D solid modeling software programs outside of engineering, such as gameSpace, have similar functions.", "Engineering,_Manufacturing": 0.9990267754, "qwen": "Yes"}
{"id": "3497359", "revid": "12217856", "url": "https://en.wikipedia.org/wiki?curid=3497359", "title": "Design for manufacturability", "text": "Design for manufacturability (also sometimes known as design for manufacturing or DFM) is the general engineering practice of designing products in such a way that they are easy to manufacture. The concept exists in almost all engineering disciplines, but the implementation differs widely depending on the manufacturing technology. DFM describes the process of designing or engineering a product in order to facilitate the manufacturing process in order to reduce its manufacturing costs. DFM will allow potential problems to be fixed in the design phase which is the least expensive place to address them. Other factors may affect the manufacturability such as the type of raw material, the form of the raw material, dimensional tolerances, and secondary processing such as finishing.\nDepending on various types of manufacturing processes there are set guidelines for DFM practices. These DFM guidelines help to precisely define various tolerances, rules and common manufacturing checks related to DFM.\nWhile DFM is applicable to the design process, a similar concept called DFSS (design for Six Sigma) is also practiced in many organizations.\nFor printed circuit boards (PCB).\nIn the PCB design process, DFM leads to a set of design guidelines that attempt to ensure manufacturability. By doing so, probable production problems may be addressed during the design stage.\nIdeally, DFM guidelines take into account the processes and capabilities of the manufacturing industry. Therefore, DFM is constantly evolving.\nAs manufacturing companies evolve and automate more and more stages of the processes, these processes tend to become cheaper. DFM is usually used to reduce these costs. For example, if a process may be done automatically by machines (i.e. SMT component placement and soldering), such process is likely to be cheaper than doing so by hand.\nFor integrated circuits (IC).\nAchieving high-yielding designs, in the state of the art VLSI technology has become an extremely challenging task due to the miniaturization as well as the complexity of leading-edge products. Here, the DFM methodology includes a set of techniques to modify the design of integrated circuits (IC) in order to make them more manufacturable, i.e., to improve their functional yield, parametric yield, or their reliability.\nBackground.\nTraditionally, in the pre-nanometer era, DFM consisted of a set of different methodologies trying to enforce some soft (recommended) design rules regarding the shapes and polygons of the physical layout of an integrated circuit. These DFM methodologies worked primarily at the full chip level. Additionally, worst-case simulations at different levels of abstraction were applied to minimize the impact of process variations on performance and other types of parametric yield loss. All these different types of worst-case simulations were essentially based on a base set of worst-case (or corner) SPICE device parameter files that were intended to represent the variability of transistor performance over the full range of variation in a fabrication process. Additionally, SPICE models should have mismatches built into them for analog circuit simulations. Many mismatches are size and orientation dependent, which can be well modeled. Always \"copy exactly\" when doing analog layouts as many mismatches are not well understood or controlled (i.e. if one device has North to South current flow, all matched devices should have North to South current flow). \nTaxonomy of yield loss mechanisms.\nThe most important yield loss models (YLMs) for VLSI ICs can be classified into several categories based on their nature.\nTechniques.\nAfter understanding the causes of yield loss, the next step is to make the design as resistant as possible. Techniques used for this include:\nAll of these require a detailed understanding of yield loss mechanisms, since these changes trade off against one another. For example, introducing redundant vias will reduce the chance of via problems, but increase the chance of unwanted shorts. Whether this is good idea, therefore, depends on the details of the yield loss models and the characteristics of the particular design.\nFor CNC machining.\nObjective.\nThe objective is to design for lower cost. The cost is driven by time, so the design must minimize the time required to not just machine (remove the material), but also the set-up time of the CNC machine, NC programming, fixturing and many other activities that are dependent on the complexity and size of the part.\nSet-Up time of operations (flip of the part).\nUnless a 4th and/or 5th axis is used, a CNC can only approach the part from a single direction. One side must be machined at a time (called an operation or \"op\"). Then the part must be flipped from side to side to machine all of the features. The geometry of the features dictates whether the part must be flipped over or not. The more ops (flip of the part), the more expensive the part because it incurs substantial set-up and load/unload time.\nEach operation (flip of the part) has set-up time, machine time, time to load/unload tools, time to load/unload parts, and time to create the NC program for each operation. If a part has only 1 operation, then parts only have to be loaded/unloaded once. If it has 5 operations, then load/unload time is significant.\nThe low hanging fruit is minimizing the number of operations (flip of the part) to create significant savings. For example, it may take only 2 minutes to machine the face of a small part, but it will take an hour to set the machine up to do it. Or, if there are 5 operations at 1.5 hours each, but only 30 minutes total machine time, then 7.5 hours is charged for just 30 minutes of machining.\nLastly, the volume (number of parts to machine) plays a critical role in amortizing the set-up time, programming time and other activities into the cost of the part. In the example above, the part in quantities of 10 could cost 7–10 times the cost in quantities of 100.\nTypically, the law of diminishing returns presents itself at volumes of 100–300 because set-up times, custom tooling and fixturing can be amortized into the noise.\nMaterial type.\nThe most easily machined types of metals include aluminum, brass, and softer metals. As materials get harder, denser and stronger, such as steel, stainless steel, titanium, and exotic alloys, they become much harder to machine and take much longer, thus being less manufacturable. Most types of plastic are easy to machine, although additions of fiberglass or carbon fiber can reduce the machinability. Plastics that are particularly soft and gummy may have machinability problems of their own.\nMaterial form.\nMetals come in all forms. In the case of aluminum as an example, bar stock and plate are the two most common forms from which machined parts are made. The size and shape of the component may determine which form of material must be used. It is common for engineering drawings to specify one form over the other. Bar stock is generally close to 1/2 of the cost of plate on a per pound basis. So although the material form isn't directly related to the geometry of the component, cost can be removed at the design stage by specifying the least expensive form of the material.\nTolerances.\nA significant contributing factor to the cost of a machined component is the geometric tolerance to which the features must be made. The tighter the tolerance required, the more expensive the component will be to machine. When designing, specify the loosest tolerance that will serve the function of the component. Tolerances must be specified on a feature by feature basis. There are creative ways to engineer components with lower tolerances that still perform as well as ones with higher tolerances.\nDesign and shape.\nAs machining is a subtractive process, the time to remove the material is a major factor in determining the machining cost. The volume and shape of the material to be removed as well as how fast the tools can be fed will determine the machining time. When using milling cutters, the strength and stiffness of the tool which is determined in part by the length to diameter ratio of the tool will play the largest role in determining that speed. The shorter the tool is relative to its diameter the faster it can be fed through the material. A ratio of 3:1 (L:D) or under is optimum. If that ratio cannot be achieved, a solution like this depicted here can be used. For holes, the length to diameter ratio of the tools are less critical, but should still be kept under 10:1.\nThere are many other types of features which are more or less expensive to machine. Generally chamfers cost less to machine than radii on outer horizontal edges. 3D interpolation is used to create radii on edges that are not on the same plane which incur 10X the cost. Undercuts are more expensive to machine. Features that require smaller tools, regardless of L:D ratio, are more expensive.\nDesign for inspection.\nThe concept of design for inspection (DFI) should complement and work in collaboration with design for manufacturability (DFM) and design for assembly (DFA) to reduce product manufacturing cost and increase manufacturing practicality. There are instances when this method could cause calendar delays since it consumes many hours of additional work such as the case of the need to prepare for design review presentations and documents. To address this, it is proposed that instead of periodic inspections, organizations could adopt the framework of empowerment, particularly at the stage of product development, wherein the senior management empowers the project leader to evaluate manufacturing processes and outcomes against expectations on product performance, cost, quality and development time. Experts, however, cite the necessity for the DFI because it is crucial in performance and quality control, determining key factors such as product reliability, safety, and life cycles. For an aerospace components company, where inspection is mandatory, there is the requirement for the suitability of the manufacturing process for inspection. Here, a mechanism is adopted such as an inspectability index, which evaluates design proposals. Another example of DFI is the concept of cumulative count of conforming chart (CCC chart), which is applied in inspection and maintenance planning for systems where different types of inspection and maintenance are available. \nDesign for additive manufacturing.\nAdditive manufacturing broadens the ability of a designer to optimize the design of a product or part (to save materials for example). Designs tailored for additive manufacturing are sometimes very different from designs tailored for machining or forming manufacturing operations.\nIn addition, due to some size constraints of additive manufacturing machines, sometimes the related bigger designs are split into smaller sections with self-assembly features or fasteners locators.\nA common characteristic of additive manufacturing methods, such as fused deposition modeling, is the need for temporary support structures for overhanging part features. Post-processing removal of these temporary support structures increases the overall cost of fabrication. Parts can be designed for additive manufacturing by eliminating or reducing the need for temporary support structures. This can be done by limiting the angle of overhanging structures to less than the limit of the given additive manufacturing machine, material, and process (for example, less than 70 degrees from vertical).", "Engineering,_Manufacturing": 0.9999763966, "qwen": "Yes"}
{"id": "266430", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=266430", "title": "Shaper", "text": "In machining, a shaper is a type of machine tool that uses linear relative motion between the workpiece and a single-point cutting tool to machine a linear toolpath. Its cut is analogous to that of a lathe, except that it is (archetypally) linear instead of helical. \nA wood shaper is a functionally different woodworking tool, typically with a powered rotating cutting head and manually fed workpiece, usually known simply as a \"shaper\" in North America and \"spindle moulder\" in the UK.\nA metalworking shaper is somewhat analogous to a metalworking planer, with the cutter riding a ram that moves relative to a stationary workpiece, rather than the workpiece moving beneath the cutter. The ram is typically actuated by a mechanical crank inside the column, though hydraulically actuated shapers are increasingly used. Adding axes of motion to a shaper can yield helical tool \npaths, as also done in helical planing.\nProcess.\nA single-point cutting tool is rigidly held in the tool holder, which is mounted on the ram. The work piece is rigidly held in a vise or clamped directly on the table. The table may be supported at the outer end. The ram reciprocates and the cutting tool, held in the tool holder, moves forwards and backwards over the work piece. In a standard shaper, cutting of material takes place during the forward stroke of the ram and the return stroke remains idle. The return is governed by a quick return mechanism. The depth of the cut increments by moving the workpiece, and the workpiece is fed by a pawl and ratchet mechanism.\nTypes.\nShapers are mainly classified as standard, draw-cut, horizontal, universal, vertical, geared, crank, hydraulic, contour and traveling head, with a horizontal arrangement most common. Vertical shapers are generally fitted with a rotary table to enable curved surfaces to be machined (same idea as in helical planing). The vertical shaper is essentially the same thing as a slotter (slotting machine), although technically a distinction can be made if one defines a true vertical shaper as a machine whose slide can be moved from the vertical. A slotter is fixed in the vertical plane\nOperation.\nThe workpiece mounts on a rigid, box-shaped table in front of the machine. The height of the table can be adjusted to suit this workpiece, and the table can traverse sideways underneath the reciprocating tool, which is mounted on the ram. Table motion may be controlled manually, but is usually advanced by an automatic feed mechanism acting on the feedscrew. The ram slides back and forth above the work. At the front end of the ram is a vertical tool slide that may be adjusted to either side of the vertical plane along the stroke axis. This tool-slide holds the \"clapper box \" and tool post, from which the tool can be positioned to cut a straight, flat surface on the top of the workpiece. The tool-slide permits feeding the tool downwards to deepen a cut. This flexibility, coupled with the use of specialized cutters and tool holders, enable the operator to cut internal and external gear teeth.\nThe ram is adjustable for stroke and, due to the geometry of the linkage, it moves faster on the return (non-cutting) stroke than on the forward, cutting stroke. This return stroke is governed by a quick return mechanism.\nUses.\nThe most common use is to machine straight, flat surfaces, but with ingenuity and some accessories a wide range of work can be done. Other examples of its use are:\nHistory.\nSamuel Bentham developed a shaper between 1791 and 1793. However, Roe (1916) credits James Nasmyth with the invention of the shaper in 1836. Shapers were very common in industrial production from the mid-19th century through the mid-20th. In current industrial practice, shapers have been largely superseded by other machine tools (especially of the CNC type), including milling machines, grinding machines, and broaching machines. But the basic function of a shaper is still sound; tooling for them is minimal and very cheap to reproduce; and they are simple and robust in construction, making their repair and upkeep easily achievable. Thus they are still popular in many machine shops, from jobbing shops or repair shops to tool and die shops, where only one or a few pieces are required to be produced and the alternative methods are cost- or tooling-intensive. They also have considerable retro appeal to many hobbyist machinists, who are happy to obtain a used shaper or, in some cases, even to build a new one from scratch.", "Engineering,_Manufacturing": 1.0000017881, "qwen": "Yes"}
{"id": "266443", "revid": "46037023", "url": "https://en.wikipedia.org/wiki?curid=266443", "title": "Metalworking", "text": "Metalworking is the process of shaping and reshaping metals to create useful objects, parts, assemblies, and large scale structures. As a term it covers a wide and diverse range of processes, skills, and tools for producing objects on every scale: from huge ships, buildings, and bridges down to precise engine parts and delicate jewelry.\nThe historical roots of metalworking predate recorded history; its use spans cultures, civilizations and millennia. It has evolved from shaping soft, native metals like gold with simple hand tools, through the smelting of ores and hot forging of harder metals like iron, up to highly technical modern processes such as machining and welding. It has been used as an industry, a driver of trade, individual hobbies, and in the creation of art; it can be regarded as both a science and a craft.\nModern metalworking processes, though diverse and specialized, can be categorized into one of three broad areas known as forming, cutting, or joining processes. Modern metalworking workshops, typically known as machine shops, hold a wide variety of specialized or general-use machine tools capable of creating highly precise, useful products. Many simpler metalworking techniques, such as blacksmithing, are no longer economically competitive on a large scale in developed countries; some of them are still in use in less developed countries, for artisanal or hobby work, or for historical reenactment.\nPrehistory.\nThe oldest archaeological evidence of copper mining and working was the discovery of a copper pendant in northern Iraq from 8,700 BCE. The earliest substantiated and dated evidence of metalworking in the Americas was the processing of copper in Wisconsin, near Lake Michigan. Copper was hammered until it became brittle, then heated so it could be worked further. In America, this technology is dated to about 4000–5000 BCE. The oldest gold artifacts in the world come from the Bulgarian Varna Necropolis and date from 4450 BCE.\nNot all metal required fire to obtain it or work it. Isaac Asimov speculated that gold was the \"first metal\". His reasoning being, that, by its chemistry, it is found in nature as nuggets of pure gold. In other words, gold, as rare as it is, is sometimes found in nature as a native metal. Some metals can also be found in meteors. Almost all other metals are found in ores, a mineral-bearing rock, that require heat or some other process to liberate the metal. Another feature of gold is that it is workable as it is found, meaning that no technology beyond a stone hammer and anvil is needed to work the metal. This is a result of gold's properties of malleability and ductility. The earliest tools were stone, bone, wood, and sinew, all of which sufficed to work gold.\nAt some unknown time, the process of liberating metals from rock by heat became known, and rocks rich in copper, tin, and lead came into demand. These ores were mined wherever they were recognized. Remnants of such ancient mines have been found all over Southwestern Asia. Metalworking was being carried out by the South Asian inhabitants of Mehrgarh between 7000 and 3300 BCE. The end of the beginning of metalworking occurs sometime around 6000 BCE when copper smelting became common in Southwestern Asia.\nAncient civilisations knew of seven metals. Here they are arranged in order of their oxidation potential (in volts):\nThe oxidation potential is important because it is one indicator of how tightly bound to the ore the metal is likely to be. As can be seen, iron is significantly higher than the other six metals while gold is dramatically lower than the six above it. Gold's low oxidation is one of the main reasons that gold is found in nuggets. These nuggets are relatively pure gold and are workable as they are found.\nCopper ore, being relatively abundant, and tin ore became the next important substances in the story of metalworking. Using heat to smelt copper from ore, a great deal of copper was produced. It was used for both jewelry and simple tools. However, copper by itself was too soft for tools requiring edges and stiffness. At some point tin was added into the molten copper and bronze was developed thereby. Bronze is an alloy of copper and tin. Bronze was an important advance because it had the edge-durability and stiffness that pure copper lacked. Until the advent of iron, bronze was the most advanced metal for tools and weapons in common use (see Bronze Age for more detail).\nOutside Southwestern Asia, these same advances and materials were being discovered and used around the world. People in China and Great Britain began using bronze with little time being devoted to copper. Japanese began the use of bronze and iron almost simultaneously. In the Americas it was different. Although the peoples of the Americas knew of metals, it was not until the European colonisation that metalworking for tools and weapons became common. Jewelry and art were the principal uses of metals in the Americas prior to European influence.\nAbout 2700 BCE, production of bronze was common in locales where the necessary materials could be assembled for smelting, heating, and working the metal. Iron was beginning to be smelted and began its emergence as an important metal for tools and weapons. The period that followed became known as the Iron Age.\nHistory.\nBy the historical periods of the Pharaohs in Egypt, the Vedic Kings in India, the Tribes of Israel, and the Maya civilization in North America, among other ancient populations, precious metals began to have value attached to them. In some cases rules for ownership, distribution, and trade were created, enforced, and agreed upon by the respective peoples. By the above periods metalworkers were very skilled at creating objects of adornment, religious artifacts, and trade instruments of precious metals (non-ferrous), as well as weaponry usually of ferrous metals and/or alloys. These skills were well executed. The techniques were practiced by artisans, blacksmiths, atharvavedic practitioners, alchemists, and other categories of metalworkers around the globe. For example, the granulation technique was employed by numerous ancient cultures before the historic record shows people traveled to far regions to share this process. Metalsmiths today still use this and many other ancient techniques.\nAs time progressed, metal objects became more common, and ever more complex. The need to further acquire and work metals grew in importance. Skills related to extracting metal ores from the earth began to evolve, and metalsmiths became more knowledgeable. Metalsmiths became important members of society. Fates and economies of entire civilizations were greatly affected by the availability of metals and metalsmiths. The metalworker depends on the extraction of precious metals to make jewelry, build more efficient electronics, and for industrial and technological applications from construction to shipping containers to rail, and air transport. Without metals, goods and services would cease to move around the globe on the scale we know today.\nGeneral processes.\nMetalworking generally is divided into three categories: \"forming\", \"cutting\", and \"joining\". Most metal cutting is done by high speed steel tools or carbide tools. Each of these categories contains various processes.\nPrior to most operations, the metal must be marked out and/or measured, depending on the desired finished product.\n\"Marking out\" (also known as layout) is the process of transferring a design or pattern to a workpiece and is the first step in the handcraft of metalworking. It is performed in many industries or hobbies, although in industry, the repetition eliminates the need to mark out every individual piece. In the metal trades area, marking out consists of transferring the engineer's plan to the workpiece in preparation for the next step, machining or manufacture.\n\"Calipers\" are hand tools designed to precisely measure the distance between two points. Most calipers have two sets of flat, parallel edges used for inner or outer diameter measurements. These calipers can be accurate to within one-thousandth of an inch (25.4 μm). Different types of calipers have different mechanisms for displaying the distance measured. Where larger objects need to be measured with less precision, a tape measure is often used.\nCasting.\nCasting achieves a specific form by pouring molten metal into a mold and allowing it to cool, with no mechanical force. Forms of casting include:\nForming processes.\nThese \"forming\" processes modify metal or workpiece by deforming the object, that is, without removing any material. Forming is done with a system of mechanical forces and, especially for bulk metal forming, with heat.\nBulk forming processes.\nPlastic deformation involves using heat or pressure to make a workpiece more conductive to mechanical force. Historically, this and casting were done by blacksmiths, though today the process has been industrialized. In bulk metal forming, the workpiece is generally heated up.\nSheet (and tube) forming processes.\nThese types of forming process involve the application of mechanical force at room temperature. However, some recent developments involve the heating of dies and/or parts. Advancements in automated metalworking technology have made progressive die stamping possible which is a method that can encompass punching, coining, bending and several other ways below that modify metal at less cost while resulting in less scrap.\nCutting processes.\n\"Cutting\" is a collection of processes wherein material is brought to a specified geometry by removing excess material using various kinds of tooling to leave a finished part that meets specifications. The net result of cutting is two products, the waste or excess material, and the finished part. In woodworking, the waste would be sawdust and excess wood. In cutting metals the waste is chips or swarf and excess metal.\nCutting processes fall into one of three major categories:\nDrilling a hole in a metal part is the most common example of a chip producing process. Using an oxy-fuel cutting torch to separate a plate of steel into smaller pieces is an example of burning. Chemical milling is an example of a specialty process that removes excess material by the use of etching chemicals and masking chemicals.\nThere are many technologies available to cut metal, including: \nCutting fluid or coolant is used where there is significant friction and heat at the cutting interface between a cutter such as a drill or an end mill and the workpiece. Coolant is generally introduced by a spray across the face of the tool and workpiece to decrease friction and temperature at the cutting tool/workpiece interface to prevent excessive tool wear. In practice there are many methods of delivering coolant.\nMilling.\nMilling is the complex shaping of metal or other materials by removing material to form the final shape. It is generally done on a milling machine, a power-driven machine that in its basic form consists of a milling cutter that rotates about the spindle axis (like a drill), and a worktable that can move in multiple directions (usually two dimensions [x and y axis] relative to the workpiece). The spindle usually moves in the z axis. It is possible to raise the table (where the workpiece rests). Milling machines may be operated manually or under computer numerical control (CNC), and can perform a vast number of complex operations, such as slot cutting, planing, drilling and threading, rabbeting, routing, etc. Two common types of mills are the horizontal mill and vertical mill.\nThe pieces produced are usually complex 3D objects that are converted into x, y, and z coordinates that are then fed into the CNC machine and allow it to complete the tasks required. The milling machine can produce most parts in 3D, but some require the objects to be rotated around the x, y, or z coordinate axis (depending on the need). Tolerances come in a variety of standards, depending on the locale. In countries still using the imperial system, this is usually in the thousandths of an inch (unit known as \"thou\"), depending on the specific machine. In many other European countries, standards following the ISO are used instead.\nIn order to keep both the bit and material cool, a high temperature coolant is used. In most cases the coolant is sprayed from a hose directly onto the bit and material. This coolant can either be machine or user controlled, depending on the machine.\nMaterials that can be milled range from aluminum to stainless steel and almost everything in between. Each material requires a different speed on the milling tool and varies in the amount of material that can be removed in one pass of the tool. Harder materials are usually milled at slower speeds with small amounts of material removed. Softer materials vary, but usually are milled with a high bit speed.\nThe use of a milling machine adds costs that are factored into the manufacturing process. Each time the machine is used coolant is also used, which must be periodically added in order to prevent breaking bits. A milling bit must also be changed as needed in order to prevent damage to the material. Time is the biggest factor for costs. Complex parts can require hours to complete, while very simple parts take only minutes. This in turn varies the production time as well, as each part will require different amounts of time.\nSafety is key with these machines. The bits are traveling at high speeds and removing pieces of usually scalding hot metal. The advantage of having a CNC milling machine is that it protects the machine operator.\nTurning.\nTurning is a metal cutting process for producing a cylindrical surface with a single point tool. The workpiece is rotated on a spindle and the cutting tool is fed into it radially, axially or both. Producing surfaces perpendicular to the workpiece axis is called facing. Producing surfaces using both radial and axial feeds is called profiling.\nA \"lathe\" is a machine tool which spins a block or cylinder of material so that when abrasive, cutting, or deformation tools are applied to the workpiece, it can be shaped to produce an object which has rotational symmetry about an axis of rotation. Examples of objects that can be produced on a lathe include candlestick holders, crankshafts, camshafts, and bearing mounts.\nLathes have four main components: the bed, the headstock, the carriage, and the tailstock. The bed is a precise & very strong base which all of the other components rest upon for alignment. The headstock's spindle secures the workpiece with a chuck, whose jaws (usually three or four) are tightened around the piece. The spindle rotates at high speed, providing the energy to cut the material. While historically lathes were powered by belts from a line shaft, modern examples uses electric motors. The workpiece extends out of the spindle along the axis of rotation above the flat bed. The carriage is a platform that can be moved, precisely and independently parallel and perpendicular to the axis of rotation. A hardened cutting tool is held at the desired height (usually the middle of the workpiece) by the toolpost. The carriage is then moved around the rotating workpiece, and the cutting tool gradually removes material from the workpiece. The tailstock can be slid along the axis of rotation and then locked in place as necessary. It may hold centers to further secure the workpiece, or cutting tools driven into the end of the workpiece.\nOther operations that can be performed with a single point tool on a lathe are:\nChamfering: Cutting an angle on the corner of a cylinder.\nParting: The tool is fed radially into the workpiece to cut off the end of a part.\nThreading: A tool is fed along and across the outside or inside surface of rotating parts to produce external or internal threads.\nBoring: A single-point tool is fed linearly and parallel to the axis of rotation to create a round hole.\nDrilling: Feeding the drill into the workpiece axially.\nKnurling: Uses a tool to produce a rough surface texture on the work piece. Frequently used to allow grip by hand on a metal part.\nModern computer numerical control (CNC) lathes and (CNC) machining centres can do secondary operations like milling by using driven tools. When driven tools are used the work piece stops rotating and the driven tool executes the machining operation with a rotating cutting tool. The CNC machines use x, y, and z coordinates in order to control the turning tools and produce the product. Most modern day CNC lathes are able to produce most turned objects in 3D.\nNearly all types of metal can be turned, although more time & specialist cutting tools are needed for harder workpieces.\nThreading.\nThere are many threading processes including: cutting threads with a tap or die, thread milling, single-point thread cutting, thread rolling, cold root rolling and forming, and thread grinding. A \"tap\" is used to cut a female thread on the inside surface of a pre-drilled hole, while a \"die\" cuts a male thread on a preformed cylindrical rod.\nGrinding.\n\"Grinding\" uses an abrasive process to remove material from the workpiece. A grinding machine is a machine tool used for producing very fine finishes, making very light cuts, or high precision forms using an abrasive wheel as the cutting device. This wheel can be made up of various sizes and types of stones, diamonds or inorganic materials.\nThe simplest grinder is a bench grinder or a hand-held angle grinder, for deburring parts or cutting metal with a zip-disc.\nGrinders have increased in size and complexity with advances in time and technology. From the old days of a manual toolroom grinder sharpening endmills for a production shop, to today's 30000 RPM CNC auto-loading manufacturing cell producing jet turbines, grinding processes vary greatly.\nGrinders need to be very rigid machines to produce the required finish. Some grinders are even used to produce glass scales for positioning CNC machine axis. The common rule is the machines used to produce scales be 10 times more accurate than the machines the parts are produced for.\nIn the past grinders were used for finishing operations only because of limitations of tooling. Modern grinding wheel materials and the use of industrial diamonds or other man-made coatings (cubic boron nitride) on wheel forms have allowed grinders to achieve excellent results in production environments instead of being relegated to the back of the shop.\nModern technology has advanced grinding operations to include CNC controls, high material removal rates with high precision, lending itself well to aerospace applications and high volume production runs of precision components.\nFiling.\n\"Filing\" is combination of grinding and saw tooth cutting using a file. Prior to the development of modern machining equipment it provided a relatively accurate means for the production of small parts, especially those with flat surfaces. The skilled use of a file allowed a machinist to work to fine tolerances and was the hallmark of the craft. Today filing is rarely used as a production technique in industry, though it remains as a common method of deburring.\nOther.\nBroaching is a machining operation used to cut keyways into shafts. Electron beam machining (EBM) is a machining process where high-velocity electrons are directed toward a work piece, creating heat and vaporizing the material. Ultrasonic machining uses ultrasonic vibrations to machine very hard or brittle materials.\nJoining processes.\nWelding.\n\"Welding\" is a fabrication process that joins materials, usually metals or thermoplastics, by causing coalescence. This is often done by melting the workpieces and adding a filler material to form a pool of molten material that cools to become a strong joint, but sometimes pressure is used in conjunction with heat, or by itself, to produce the weld.\nMany different energy sources can be used for welding, including a gas flame, an electric arc, a laser, an electron beam, friction, and ultrasound. While often an industrial process, welding can be done in many different environments, including open air, underwater and in space. Regardless of location, however, welding remains dangerous, and precautions must be taken to avoid burns, electric shock, poisonous fumes, and overexposure to ultraviolet light.\nBrazing.\n\"Brazing\" is a joining process in which a filler metal is melted and drawn into a capillary formed by the assembly of two or more work pieces. The filler metal reacts metallurgically with the workpieces and solidifies in the capillary, forming a strong joint. Unlike welding, the work piece is not melted. Brazing is similar to soldering, but occurs at temperatures in excess of . Brazing has the advantage of producing less thermal stresses than welding, and brazed assemblies tend to be more ductile than weldments because alloying elements can not segregate and precipitate.\nBrazing techniques include, flame brazing, resistance brazing, furnace brazing, diffusion brazing, inductive brazing and vacuum brazing.\nSoldering.\n\"Soldering\" is a joining process that occurs at temperatures below . It is similar to brazing in the way that a filler is melted and drawn into a capillary to form a joint, although at a lower temperature. Because of this lower temperature and different alloys used as fillers, the metallurgical reaction between filler and work piece is minimal, resulting in a weaker joint.\nRiveting.\n\"Riveting\" is one of the most ancient metalwork joining processes. Its use declined markedly during the second half of the 20th century, but it still retains important uses in industry and construction, and in artisan crafts such as jewellery, medieval armouring and metal couture in the early 21st century. The earlier use of rivets is being superseded by improvements in welding and component fabrication techniques.\nA rivet is essentially a two-headed and unthreaded bolt which holds two other pieces of metal together. Holes are drilled or punched through the two pieces of metal to be joined. The holes being aligned, a rivet is passed through the holes and permanent heads are formed onto the ends of the rivet utilizing hammers and forming dies (by either cold working or hotworking).\nRivets are commonly purchased with one head already formed.\nWhen it is necessary to remove rivets, one of the rivet's heads is sheared off with a cold chisel. The rivet is then driven out with a hammer and punch.\nMechanical fixings.\nThis includes screws, as well as bolts. This is often used as it requires relatively little specialist equipment, and are therefore often used in flat-pack furniture. It can also be used when a metal is joined to another material (such as wood) or a particular metal does not weld well (such as aluminum). This can be done to directly join metals, or with an intermediate material such as nylon. While often weaker than other methods such as welding or brazing, the metal can easily be removed and therefore reused or recycled. It can also be done in conjunction with an epoxy or glue, reverting its ecological benefits.\nAssociated processes.\nWhile these processes are not primary metalworking processes, they are often performed before or after metalworking processes.\nHeat treatment.\nMetals can be heat treated to alter the properties of strength, ductility, toughness, hardness or resistance to corrosion. Common heat treatment processes include annealing, precipitation hardening, quenching, and tempering:\nOften, mechanical and thermal treatments are combined in what is known as thermo-mechanical treatments for better properties and more efficient processing of materials. These processes are common to high alloy special steels, super alloys and titanium alloys.\nPlating.\nElectroplating is a common surface-treatment technique. It involves bonding a thin layer of another metal such as gold, silver, chromium or zinc to the surface of the product by hydrolysis. It is used to reduce corrosion, create abrasion resistance and improve the product's aesthetic appearance. Plating can even change the properties of the original part including conductivity, heat dissipation or structural integrity. There are four main electroplating methods to ensure proper coating and cost effectiveness per product: mass plating, rack plating, continuous plating and line plating.\nThermal spraying.\nThermal spraying techniques are another popular finishing option, and often have better high temperature properties than electroplated coatings due to the thicker coating. The four main thermal spray processes include electric wire arc spray, flame (oxy acetylene combustion) spray, plasma spray and high velocity oxy fuel (HVOF) spray.\nSee also.\nGeneral:", "Engineering,_Manufacturing": 0.9995458126, "qwen": "Yes"}
{"id": "50682", "revid": "15989103", "url": "https://en.wikipedia.org/wiki?curid=50682", "title": "Line matrix printer", "text": "A line matrix printer is a computer printer that is a compromise between a line printer and a dot matrix printer. A line matrix printer prints page-wide lines of dots, building up a line of text by printing lines of dots.\nApplications.\nLine matrix printers are used for high-speed printing applications They are used to produce invoices, bank statements, product shipment and transportation documentation as well as product compliance labels.\nLine matrix printers can print text, bar codes and graphics.\nWhen implemented as impact printers, they can be the least expensive to operate per page.\nHow it works.\nDot matrix printers are widely used because of their low cost per page. Dot matrix printers are divided into two main groups: serial dot matrix printers and line matrix printers.\nA serial dot matrix printer has a print head that runs back and forth, or in an up and down motion, on the page and prints by impact, striking an ink-soaked cloth ribbon against the paper, much like the print mechanism on a typewriter. However, unlike a typewriter or daisy wheel printer, letters are drawn out of a dot matrix, and thus, varied fonts and arbitrary graphics can be produced. Because the printing involves mechanical pressure, these printers can create carbon copies and carbonless copies.\nBoth line matrix and serial dot matrix printers use pins to strike against the inked ribbon, making dots on the paper and forming the desired characters. The difference is that a line matrix printer uses a hammer bank (or print-shuttle) instead of print head. This print-shuttle has hammers instead of print wires, and these hammers are arranged in a horizontal row instead in vertical column. The hammer bank uses the same technology as the permanent magnet print head with the small difference that instead of print wires the print-shuttle has hammers.\nThe permanent magnetic field holds the hammer spring in stressed, ready to strike position. The driver sends electric current to hammer coil, which creates an electromagnetic field opposing the permanent magnetic field. When the two fields equalize, the energy stored in the spring is released to strike the hammer against the ribbon and print a dot on the paper.\nDuring the printing process the print-shuttle vibrates in horizontal direction with high speed while the print hammers are fired selectively. Each hammer prints a series of dots in horizontal direction for one pass of the shuttle, then paper advances at one step and the shuttle prints the following row of dots.", "Engineering,_Manufacturing": 0.9990481138, "qwen": "Yes"}
{"id": "1155516", "revid": "32308078", "url": "https://en.wikipedia.org/wiki?curid=1155516", "title": "Shim (spacer)", "text": "A shim is a thin and often tapered or wedged piece of material, used to fill small gaps or spaces between objects. Shims are typically used in order to support, adjust for better fit, or provide a level surface. Shims may also be used as spacers to fill gaps between parts subject to wear.\nMaterials.\nMany materials make suitable shim stock (also often styled shimstock), or base material, depending on the context: wood, stone, plastic, metal, or even paper (e.g., when used under a table leg to level the table surface). High quality shim stock can be bought commercially, for example as laminated shims, but shims are often created ad hoc from whatever material is immediately available.\nLaminated shim stock is stacked foil that can be peeled off one layer at a time to adjust the thickness of the shim.\nApplications.\nIn automobiles, shims are commonly used to adjust the clearance or space between two parts. For example, shims are inserted into or under bucket tappets to control valve clearances. Clearance is adjusted by changing the thickness of the shim. \nIn assembly and weld fixtures precision metal shims are used between two parts so that the final production parts are created within the product drawing's specified tolerances. \nOn machinery installations (pumps, motors, etc.) the recommended practice requires shims under every equipment support foot. This guarantees a flexibility for adjustments, like a slight raising or lowering of a motor, when parts of the machinery need to be replaced.\nIn carpentry, small pieces of wood may be used to align gaps between larger timbers.\nIn masonry, small stones may be used to align or fill gaps between larger bricks or slabs.\nIn luthiery, a thin strip of various materials (most often steel or wood) can be used beneath the nut or the saddle of a stringed instrument (such as a guitar, mandolin, ukulele or banjo) to raise the height of either.\nOn guitars with a bolt-on or screwed-on neck, the angle of the neck can be adjusted by shimming. On some models a strip of sanding paper was routinely inserted during final adjustment at the factory. Guitarists have often used strips cut from business cards, credit cards or picks as shim material, while luthiery supply stores have started to sell specialized hardwood precision wedges for that purpose.\nOn printed circuit boards, special CPU shims are used to protect the central processing unit when installing a heat sink.\nIn nuclear magnetic resonance spectroscopy, \"\"shimming\" an NMR magnet\" is a procedure to generate homogeneous magnetic field along the sample volume to obtain pure Lorentzian line shapes of various resonances in the spectrum. This is accomplished by manual shimming of individual shims, or automatic shimming procedure. ", "Engineering,_Manufacturing": 1.000007987, "qwen": "Yes"}
{"id": "1159939", "revid": "12136076", "url": "https://en.wikipedia.org/wiki?curid=1159939", "title": "Apple ProFile", "text": "The ProFile (codenamed Pippin) was the first hard disk drive produced by Apple Computer, initially for use with the Apple III personal computer. The original model had a formatted capacity of 5 MB and connected to a special interface card that plugged into an Apple III slot. In 1983, Apple offered a ProFile interface card for the Apple II, with software support for Apple ProDOS and Apple Pascal.\nAdditionally, in 1983, Apple introduced the Lisa computer, which was normally sold with a ProFile. The ProFile could be connected to the built-in parallel port of the Lisa, or to a port on an optional dual-port parallel interface card. Up to three such interface cards could be installed, so in principle up to seven ProFile drives could be used on a Lisa.\nThe 5 MB ProFile was Apple's first hard drive, and was introduced in September 1981 at a price of . Later, a 10 MB model was offered, but required an upgraded PROM/interface card to recognize the additional 5 MB.\nInternally, the ProFile consisted of a bare Seagate ST-506 stepper motor drive and mechanism, without the usual Seagate electronics, a digital and an analog circuit board designed and manufactured by Apple, and a power supply.\nLater Lisa models could be configured with an internal 10 MB \"Widget\" voice-coil drive with a proprietary controller designed and built entirely by Apple, but the Widget was never offered as an external product for use with other Apple computers.\nApple did not offer another hard drive until it released the Hard Disk 20 designed specifically for the Macintosh 512K in September 1985 which could not be used on the Apple II or III families, or Lisa series. The ProFile could not be used on the Macintosh or the Apple IIc (for which Apple never offered an external hard disk drive of any kind).\nBy September 1986, the ProFile would be superseded by the introduction of the first cross-platform Hard Disk 20SC SCSI-based drive for the Macintosh and interface card for the Apple II family (excluding the IIc series, which had no SCSI interface of any kind) and Lisa/XL series.", "Engineering,_Manufacturing": 0.999139607, "qwen": "Yes"}
{"id": "28183104", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=28183104", "title": "Polygon soup", "text": "A polygon soup is a set of unorganized polygons, typically triangles, before the application of any structuring operation, such as e.g. octree grouping.\nThe term must not to be confused with the \"PolySoup\" operation available in the 3D package Houdini, whose goal is to optimize the storage space needed by some piece of geometry through the reduction of the underlying number of polygon soups used in its representation. This is accomplished by removing redundant data points (e.g. vertices with the same position) without altering the topology or assigned properties of the optimized geometry in relation to the input one. As a result of this optimization, there can be savings in the storage and processing of large polygon meshes. These savings can have a bigger impact the larger the input data is. For instance, fluid simulations, particle simulations, rigid-body simulations, environments, and character models can reach into the millions of polygons for feature films, incurring in large storage and read/write costs. In those cases, reducing the number of polygon soups required to represent such data can lead to important savings in storage use and compute time.", "Engineering,_Manufacturing": 0.9999965429, "qwen": "Yes"}
{"id": "28184616", "revid": "1113162921", "url": "https://en.wikipedia.org/wiki?curid=28184616", "title": "Advanced Integrated Manufacturing", "text": "Advanced Integrated Manufacturing Corp. Ltd. (AIM Corp) is a Singapore-based Electronic Manufacturing Services (EMS) provider. The company is listed on the SGX, the Singapore stock exchange. The company is involved in aerospace, life sciences, telecommunications, fiber optics and other information science manufacturing applications.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "30234468", "revid": "4034676", "url": "https://en.wikipedia.org/wiki?curid=30234468", "title": "Formability", "text": "Formability is the ability of a given metal workpiece to undergo plastic deformation without being damaged. The plastic deformation capacity of metallic materials, however, is limited to a certain extent, at which point, the material could experience tearing or fracture (breakage).\nProcesses affected by the formability of a material include: rolling, extrusion, forging, rollforming, stamping, and hydroforming.\nFracture strain.\nA general parameter that indicates the formability and ductility of a material is the fracture strain which is determined by a uniaxial tensile test (see also fracture toughness). The strain identified by this test is defined by elongation with respect to a reference length. For example, a length of is used for the standardized uniaxial test of flat specimens, pursuant to EN 10002. It is important to note that deformation is homogeneous up to uniform elongation. Strain subsequently localizes until fracture occurs. Fracture strain is not an engineering strain since distribution of the deformation is inhomogeneous within the reference length. Fracture strain is nevertheless a rough indicator of the formability of a material. Typical values of the fracture strain are: 7% for ultra-high-strength material, and over 50% for mild-strength steel.\nForming limits for sheet forming.\nOne main failure mode is caused by tearing of the material. This is typical for sheet-forming applications.\nA neck may appear at a certain forming stage. This is an indication of localized plastic deformation. Whereas more or less homogeneous deformation takes place in and around the subsequent neck location in the early stable deformation stage, almost all deformation is concentrated in the neck zone during the quasi-stable and unstable deformation phase. This leads to material failure manifested by tearing. Forming-limit curves depict the extreme, but still possible, deformation which a sheet material may undergo during any stage of the stamping process. These limits depend on the deformation mode and the ratio of the surface strains. The major surface strain has a minimum value when plane strain deformation occurs, which means that the corresponding minor surface strain is zero. Forming limits are a specific material property. Typical plane strain values range from 10% for high-strength grades and 50% or above for mild-strength materials and those with very good formability.\nForming limit diagrams are often used to graphically or mathematically represent formability. It is recognized by many authors that the nature of fracture and therefore the Forming limit diagrams are intrinsically non-deterministic since large variations might be observed even within a single experimental campaign.\nDeep drawability.\nA classic form of sheetforming is deep drawing, which is done by drawing a sheet by means of a punch tool pressing on the inner region of the sheet, whereas the side material held by a blankholder can be drawn toward the center. It has been observed that materials with outstanding deep drawability behave anisotropically (see: anisotropy). Plastic deformation in the surface is much more pronounced than in the thickness. The lankford coefficient (r) is a specific material property indicating the ratio between width deformation and thickness deformation in the uniaxial tensile test. Materials with very good deep drawability have an \"r\" value of 2 or below. The positive aspect of formability with respect to the forming limit curve (forming limit diagram) is seen in the deformation paths of the material that are concentrated in the extreme left of the diagram, where the forming limits become very large.\nDuctility.\nAnother failure mode that may occur without any tearing is ductile fracture after plastic deformation (ductility). This may occur as a result of bending or shear deformation (inplane or through the thickness). The failure mechanism may be due to void nucleation and expansion on a microscopic level. Microcracks and subsequent macrocracks may appear when deformation of the material between the voids has exceeded the limit. Extensive research has focused in recent years on understanding and modeling ductile fracture. The approach has been to identify ductile forming limits using various small-scale tests that show different strain ratios or stress triaxialities. An effective measure of this type of forming limit is the minimum radius in roll-forming applications (half the sheet thickness for materials with good and three times the sheet thickness for materials with low formability).\nUse of formability parameters.\nKnowledge of the material formability is very important to the layout and design of any industrial forming process. Simulations using the finite-element method and use of formability criteria such as the forming limit curve (forming limit diagram) enhance and, in some cases, are indispensable to certain tool design processes (also see: Sheet metal forming simulation and Sheet metal forming analysis).\nIDDRG.\nOne major objective of the International Deep Drawing Research Group (IDDRG, from 1957) is the investigation, exchange and dissemination of knowledge and experience about the formability of sheet materials.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "1964641", "revid": "19089174", "url": "https://en.wikipedia.org/wiki?curid=1964641", "title": "Korea General Machinery Trading Corporation", "text": "The Korea General Machinery Trading Corporation  is a North Korean machine company. It is headquartered in the Tongdaewon District near the capital, Pyongyang.\nThe company imports steel, chemical raw stock, and machine tools. It produces machine tools, metal parts, gears, electric motors, generators, hydroelectric generators, pumps, valves, mining equipment, rolling stock and other machinery.\nTaean Heavy Machine Complex.\nThe Taean Heavy Machine Complex in Tongdaewon produces hydroelectric generators and other thermal power generating equipment, including turbines, motors, transformers, etc. Taean manufactures different sizes classes of hydroelectric equipment in its Tongsuse Class, including a 50,000 kVA generator.\nHuichon Machine Tool Factory.\nHuichon Machine Tool Factory in Huichon is North Korea's leading manufacturer of heavy-duty machine tools for domestic use and for export. The 50-year-old factory group is involved in machine tool production processes including steel-making, casting, processing, assembly, painting and packing. Product is produced on serial basis and small lot basis.\nIts output of precision machine tools includes an assortment of spline-grinding machines and industrial lathes.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "4567118", "revid": "45479401", "url": "https://en.wikipedia.org/wiki?curid=4567118", "title": "Polyplex (company)", "text": "Polyplex Corporation Ltd. is an Indian multinational company which produces biaxially oriented polyester (BoPET) film for packaging, electrical and various industrial applications.\nThe company is a major exporter of PET film to the United States, Europe, Southeast Asia, South America and Australia.\nManufacturing facilities.\nIt has manufacturing facilities in India, Thailand, Turkey, the US, and Indonesia. The company, headquartered in Noida, adjacent to New Delhi, operates six manufacturing facilities through its own operations and subsidiaries:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "11200529", "revid": "16909869", "url": "https://en.wikipedia.org/wiki?curid=11200529", "title": "Manufacturing engineering", "text": "Manufacturing engineering or production engineering is a branch of professional engineering that shares many common concepts and ideas with other fields of engineering such as mechanical, chemical, electrical, and industrial engineering. \nManufacturing engineering requires the ability to plan the practices of manufacturing; to research and to develop tools, processes, machines and equipment; and to integrate the facilities and systems for producing quality products with the optimum expenditure of capital.\nThe manufacturing or production engineer's primary focus is to turn raw material into an updated or new product in the most effective, efficient & economic way possible. An example would be a company uses computer integrated technology in order for them to produce their product so that it is faster and uses less human labor.\nOverview.\nManufacturing Engineering is based on core industrial engineering and mechanical engineering skills, adding important elements from mechatronics, commerce, economics and business management.\nThis field also deals with the integration of different facilities and systems for producing quality products (with optimal expenditure) by applying the principles of physics and the results of manufacturing systems studies, such as the following: \nManufacturing engineers develop and create physical artifacts, production processes, and technology. It is a very broad area which includes the design and development of products. Manufacturing engineering is considered to be a subdiscipline of industrial engineering/systems engineering and has very strong overlaps with mechanical engineering. Manufacturing engineers' success or failure directly impacts the advancement of technology and the spread of innovation. This field of manufacturing engineering emerged from tool and die discipline in the early 20th century. It expanded greatly from the 1960s when industrialized countries introduced factories with:\n1. Numerical control machine tools and automated systems of production.\n2. Advanced statistical methods of quality control: These factories were pioneered by the American electrical engineer William Edwards Deming, who was initially ignored by his home country. The same methods of quality control later turned Japanese factories into world leaders in cost-effectiveness and production quality.\n3. Industrial robots on the factory floor, introduced in the late 1970s: These computer-controlled welding arms and grippers could perform simple tasks such as attaching a car door quickly and flawlessly 24 hours a day. This cut costs and improved production speed.\nHistory.\nThe history of manufacturing engineering can be traced to factories in the mid 19th century USA and 18th century UK. Although large home production sites and workshops were established in China, ancient Rome and the Middle East, the Venice Arsenal provides one of the first examples of a factory in the modern sense of the word. Founded in 1104 in the Republic of Venice several hundred years before the Industrial Revolution, this factory mass-produced ships on assembly lines using manufactured parts. The Venice Arsenal apparently produced nearly one ship every day and, at its height, employed 16,000 people.\nMany historians regard Matthew Boulton's Soho Manufactory (established in 1761 in Birmingham) as the first modern factory. Similar claims can be made for John Lombe's silk mill in Derby (1721), or Richard Arkwright's Cromford Mill (1771). The Cromford Mill was purpose-built to accommodate the equipment it held and to take the material through the various manufacturing processes. One historian, Jack Weatherford, contends that the first factory was in Potosí. The Potosi factory took advantage of the abundant silver that was mined nearby and processed silver ingot slugs into coins.\nBritish colonies in the 19th century built factories simply as buildings where a large number of workers gathered to perform hand labor, usually in textile production. This proved more efficient for the administration and distribution of materials to individual workers than earlier methods of manufacturing, such as cottage industries or the putting-out system.\nCotton mills used inventions such as the steam engine and the power loom to pioneer the industrial factories of the 19th century, where precision machine tools and replaceable parts allowed greater efficiency and less waste. This experience formed the basis for the later studies of manufacturing engineering. Between 1820 and 1850, non-mechanized factories supplanted traditional artisan shops as the predominant form of manufacturing institution.\nHenry Ford further revolutionized the factory concept and thus manufacturing engineering in the early 20th century with the innovation of mass production. Highly specialized workers situated alongside a series of rolling ramps would build up a product such as (in Ford's case) an automobile. This concept dramatically decreased production costs for virtually all manufactured goods and brought about the age of consumerism.\nModern developments.\nModern manufacturing engineering studies include all intermediate processes required for the production and integration of a product's components.\nSome industries, such as semiconductor and steel manufacturers use the term \"fabrication\" for these processes.\nAutomation is used in different processes of manufacturing such as machining and welding. Automated manufacturing refers to the application of automation to produce goods in a factory. The main advantages of automated manufacturing for the manufacturing process are realized with effective implementation of automation and include: higher consistency and quality, reduction of lead times, simplification of production, reduced handling, improved work flow, and improved worker morale.\nRobotics is the application of mechatronics and automation to create robots, which are often used in manufacturing to perform tasks that are dangerous, unpleasant, or repetitive. These robots may be of any shape and size, but all are preprogrammed and interact physically with the world. To create a robot, an engineer typically employs kinematics (to determine the robot's range of motion) and mechanics (to determine the stresses within the robot). Robots are used extensively in manufacturing engineering.\nRobots allow businesses to save money on labor, perform tasks that are either too dangerous or too precise for humans to perform economically, and to ensure better quality. Many companies employ assembly lines of robots, and some factories are so robotized that they can run by themselves. Outside the factory, robots have been employed in bomb disposal, space exploration, and many other fields. Robots are also sold for various residential applications.\nEducation.\nManufacturing Engineers.\nManufacturing Engineers focus on the design, development and operation of integrated systems of production to obtain high quality & economically competitive products. These systems may include material handling equipment, machine tools, robots or even computers or networks of computers.\nCertification Programs.\nManufacturing engineers possess an associate's or bachelor's degree in engineering with a major in manufacturing engineering. The length of study for such a degree is usually two to five years followed by five more years of professional practice to qualify as a professional engineer. Working as a manufacturing engineering technologist involves a more applications-oriented qualification path.\nAcademic degrees for manufacturing engineers are usually the Associate or Bachelor of Engineering, [BE] or [BEng], and the Associate or Bachelor of Science, [BS] or [BSc]. For manufacturing technologists the required degrees are Associate or Bachelor of Technology [B.TECH] or Associate or Bachelor of Applied Science [BASc] in Manufacturing, depending upon the university. Master's degrees in engineering manufacturing include Master of Engineering [ME] or [MEng] in Manufacturing, Master of Science [M.Sc] in Manufacturing Management, Master of Science [M.Sc] in Industrial and Production Management, and Master of Science [M.Sc] as well as Master of Engineering [ME] in Design, which is a subdiscipline of manufacturing. Doctoral [PhD] or [DEng] level courses in manufacturing are also available depending on the university.\nThe undergraduate degree curriculum generally includes courses in physics, mathematics, computer science, project management, and specific topics in mechanical and manufacturing engineering. Initially such topics cover most, if not all, of the subdisciplines of manufacturing engineering. Students then choose to specialize in one or more subdisciplines towards the end of their degree work.\nSyllabus.\nThe Foundational Curriculum for a Bachelor's Degree of Manufacturing Engineering or Production Engineering includes below mentioned syllabus. This syllabus is closely related to Industrial Engineering and Mechanical Engineering, but it differs by placing more emphasis on Manufacturing Science or Production Science. It includes the following areas:\nA degree in Manufacturing Engineering typically differs from Mechanical Engineering in only a few specialized classes. Mechanical Engineering degrees focus more on the product design process and on complex products which requires more mathematical expertise.\nManufacturing engineering certification.\nCertification and licensure:\nIn some countries, \"professional engineer\" is the term for registered or licensed engineers who are permitted to offer their professional services directly to the public. Professional Engineer, abbreviated (PE - USA) or (PEng - Canada), is the designation for licensure in North America. In order to qualify for this license, a candidate needs a bachelor's degree from an ABET recognized university in the USA, a passing score on a state examination, and four years of work experience usually gained via a structured internship. In the USA, more recent graduates have the option of dividing this licensure process into two segments. The Fundamentals of Engineering (FE) exam is often taken immediately after graduation and the Principles and Practice of Engineering exam is taken after four years of working in a chosen engineering field.\nSociety of Manufacturing Engineers (SME) certification (USA):\nThe SME administers qualifications specifically for the manufacturing industry. These are not degree level qualifications and are not recognized at the professional engineering level. The following discussion deals with qualifications in the USA only. Qualified candidates for the Certified Manufacturing Technologist Certificate (CMfgT) must pass a three-hour, 130-question multiple-choice exam. The exam covers math, manufacturing processes, manufacturing management, automation, and related subjects. Additionally, a candidate must have at least four years of combined education and manufacturing-related work experience.\nCertified Manufacturing Engineer (CMfgE) is an engineering qualification administered by the Society of Manufacturing Engineers, Dearborn, Michigan, USA. Candidates qualifying for a Certified Manufacturing Engineer credential must pass a four-hour, 180 question multiple-choice exam which covers more in-depth topics than does the CMfgT exam. CMfgE candidates must also have eight years of combined education and manufacturing-related work experience, with a minimum of four years of work experience.\nCertified Engineering Manager (CEM). The Certified Engineering Manager Certificate is also designed for engineers with eight years of combined education and manufacturing experience. The test is four hours long and has 160 multiple-choice questions. The CEM certification exam covers business processes, teamwork, responsibility, and other management-related categories.\nModern tools.\nMany manufacturing companies, especially those in industrialized nations, have begun to incorporate computer-aided engineering (CAE) programs into their existing design and analysis processes, including 2D and 3D solid modeling computer-aided design (CAD). This method has many benefits, including easier and more exhaustive visualization of products, the ability to create virtual assemblies of parts, and ease of use in designing mating interfaces and tolerances.\nOther CAE programs commonly used by product manufacturers include product life cycle management (PLM) tools and analysis tools used to perform complex simulations. Analysis tools may be used to predict product response to expected loads, including fatigue life and manufacturability. These tools include finite element analysis (FEA), computational fluid dynamics (CFD), and computer-aided manufacturing (CAM).\nUsing CAE programs, a mechanical design team can quickly and cheaply iterate the design process to develop a product that better meets cost, performance, and other constraints. No physical prototype need be created until the design nears completion, allowing hundreds or thousands of designs to be evaluated, instead of relatively few. In addition, CAE analysis programs can model complicated physical phenomena which cannot be solved by hand, such as viscoelasticity, complex contact between mating parts, or non-Newtonian flows.\nJust as manufacturing engineering is linked with other disciplines, such as mechatronics, multidisciplinary design optimization (MDO) is also being used with other CAE programs to automate and improve the iterative design process. MDO tools wrap around existing CAE processes, allowing product evaluation to continue even after the analyst goes home for the day. They also utilize sophisticated optimization algorithms to more intelligently explore possible designs, often finding better, innovative solutions to difficult multidisciplinary design problems.\nManufacturing Engineering around the world.\nManufacturing engineering is an extremely important discipline worldwide. It goes by different names in different countries. In the United States and the continental European Union it is commonly known as Industrial Engineering and in the United Kingdom and Australia it is called Manufacturing Engineering \nSubdisciplines.\nMechanics.\nMechanics, in the most general sense, is the study of forces and their effects on matter. Typically, engineering mechanics is used to analyze and predict the acceleration and deformation (both elastic and plastic) of objects under known forces (also called loads) or stresses. Subdisciplines of mechanics include:\nIf the engineering project were to design a vehicle, statics might be employed to design the frame of the vehicle in order to evaluate where the stresses will be most intense. Dynamics might be used when designing the car's engine to evaluate the forces in the pistons and cams as the engine cycles. Mechanics of materials might be used to choose appropriate materials for the manufacture of the frame and engine. Fluid mechanics might be used to design a ventilation system for the vehicle or to design the intake system for the engine.\nKinematics.\nKinematics is the study of the motion of bodies (objects) and systems (groups of objects), while ignoring the forces that cause the motion. The movement of a crane and the oscillations of a piston in an engine are both simple kinematic systems. The crane is a type of open kinematic chain, while the piston is part of a closed four-bar linkage. Engineers typically use kinematics in the design and analysis of mechanisms. Kinematics can be used to find the possible range of motion for a given mechanism, or, working in reverse, can be used to design a mechanism that has a desired range of motion.\nDrafting.\nDrafting or technical drawing is the means by which manufacturers create instructions for manufacturing parts. A technical drawing can be a computer model or hand-drawn schematic showing all the dimensions necessary to manufacture a part, as well as assembly notes, a list of required materials, and other pertinent information. A U.S engineer or skilled worker who creates technical drawings may be referred to as a drafter or draftsman. Drafting has historically been a two-dimensional process, but computer-aided design (CAD) programs now allow the designer to create in three dimensions.\nInstructions for manufacturing a part must be fed to the necessary machinery, either manually, through programmed instructions, or through the use of a computer-aided manufacturing (CAM) or combined CAD/CAM program. Optionally, an engineer may also manually manufacture a part using the technical drawings, but this is becoming an increasing rarity with the advent of computer numerically controlled (CNC) manufacturing. Engineers primarily manufacture parts manually in the areas of applied spray coatings, finishes, and other processes that cannot economically or practically be done by a machine.\nDrafting is used in nearly every subdiscipline of mechanical and manufacturing engineering, and by many other branches of engineering and architecture. Three-dimensional models created using CAD software are also commonly used in finite element analysis (FEA) and computational fluid dynamics (CFD).\nMachine Tools and Metal Fabrication.\nMachine tools employ some sort of tool that does the cutting or shaping. All machine tools have some means of constraining the workpiece and provide a guided movement of the parts of the machine. Metal fabrication is the building of metal structures by cutting, bending, and assembling processes.\nComputer Integrated Manufacturing.\nComputer-integrated manufacturing (CIM) is the manufacturing approach of using computers to control the entire production process. Computer-integrated manufacturing is used in automotive, aviation, space, and ship building industries.\nMechatronics.\nMechatronics is an engineering discipline that deals with the convergence of electrical, mechanical and manufacturing systems. Such combined systems are known as electromechanical systems and are widespread. Examples include automated manufacturing systems, heating, ventilation and air-conditioning systems, and various aircraft and automobile subsystems.\nThe term mechatronics is typically used to refer to macroscopic systems, but futurists have predicted the emergence of very small electromechanical devices. Already such small devices, known as Microelectromechanical systems (MEMS), are used in automobiles to initiate the deployment of airbags, in digital projectors to create sharper images, and in inkjet printers to create nozzles for high-definition printing. In future it is hoped that such devices will be used in tiny implantable medical devices and to improve optical communication.\nTextile engineering.\nTextile engineering courses deal with the application of scientific and engineering principles to the design and control of all aspects of fiber, textile, and apparel processes, products, and machinery. These include natural and man-made materials, interaction of materials with machines, safety and health, energy conservation, and waste and pollution control. Additionally, students are given experience in plant design and layout, machine and wet process design and improvement, and designing and creating textile products. Throughout the textile engineering curriculum, students take classes from other engineering and disciplines including: mechanical, chemical, materials and industrial engineering.\nAdvanced composite materials.\nAdvanced composite materials (engineering) (ACMs) are also known as advanced polymer matrix composites. These are generally characterized or determined by unusually high strength fibres with unusually high stiffness, or modulus of elasticity characteristics, compared to other materials, while bound together by weaker matrices. Advanced composite materials have broad, proven applications, in the aircraft, aerospace, and sports equipment sectors. Even more specifically ACMs are very attractive for aircraft and aerospace structural parts. Manufacturing ACMs is a multibillion-dollar industry worldwide. Composite products range from skateboards to components of the space shuttle. The industry can be generally divided into two basic segments, industrial composites and advanced composites.\nEmployment.\nManufacturing engineering is just one facet of the engineering manufacturing industry. Manufacturing engineers enjoy improving the production process from start to finish. They have the ability to keep the whole production process in mind as they focus on a particular portion of the process. Successful students in manufacturing engineering degree programs are inspired by the notion of starting with a natural resource, such as a block of wood, and ending with a usable, valuable product, such as a desk, produced efficiently and economically.\nManufacturing engineers are closely connected with engineering and industrial design efforts. Examples of major companies that employ manufacturing engineers in the United States include General Motors Corporation, Ford Motor Company, Chrysler, Boeing, Gates Corporation and Pfizer. Examples in Europe include Airbus, Daimler, BMW, Fiat, Navistar International, and Michelin Tyre.\nIndustries where manufacturing engineers are generally employed include:\nFrontiers of research.\nFlexible manufacturing systems.\nA flexible manufacturing system (FMS) is a manufacturing system in which there is some amount of flexibility that allows the system to react to changes, whether predicted or unpredicted. This flexibility is generally considered to fall into two categories, both of which have numerous subcategories.\nThe first category, machine flexibility, covers the system's ability to be changed to produce new product types and the ability to change the order of operations executed on a part. The second category, called routing flexibility, consists of the ability to use multiple machines to perform the same operation on a part, as well as the system's ability to absorb large-scale changes, such as in volume, capacity, or capability.\nMost FMS systems comprise three main systems. The work machines, which are often automated CNC machines, are connected by a material handling system to optimize parts flow, and to a central control computer, which controls material movements and machine flow. The main advantages of an FMS is its high flexibility in managing manufacturing resources like time and effort in order to manufacture a new product. The best application of an FMS is found in the production of small sets of products from a mass production.\nComputer integrated manufacturing.\nComputer-integrated manufacturing (CIM) in engineering is a method of manufacturing in which the entire production process is controlled by computer. Traditionally separated process methods are joined through a computer by CIM. This integration allows the processes to exchange information and to initiate actions. Through this integration, manufacturing can be faster and less error-prone, although the main advantage is the ability to create automated manufacturing processes. Typically CIM relies on closed-loop control processes based on real-time input from sensors. It is also known as flexible design and manufacturing.\nFriction stir welding.\nFriction stir welding was discovered in 1991 by The Welding Institute (TWI). This innovative steady state (non-fusion) welding technique joins previously un-weldable materials, including several aluminum alloys. It may play an important role in the future construction of airplanes, potentially replacing rivets. Current uses of this technology to date include: welding the seams of the aluminum main space shuttle external tank, the Orion Crew Vehicle test article, Boeing Delta II and Delta IV Expendable Launch Vehicles and the SpaceX Falcon 1 rocket; armor plating for amphibious assault ships; and welding the wings and fuselage panels of the new Eclipse 500 aircraft from Eclipse Aviation, among an increasingly growing range of uses.\nOther areas of research are Product Design, MEMS (Micro-Electro-Mechanical Systems), Lean Manufacturing, Intelligent Manufacturing Systems, Green Manufacturing, Precision Engineering, Smart Materials, etc.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "11205281", "revid": "1160741158", "url": "https://en.wikipedia.org/wiki?curid=11205281", "title": "Bologna bottle", "text": "A Bologna bottle, also known as a Bologna phial or philosophical vial, is a glass bottle which has great external strength, often used in physics demonstrations and magic tricks. The exterior is generally strong enough that one could pound a nail into a block of wood using the bottle as a hammer; however, even a small scratch on the interior would cause it to crumble.\nIt is created by heating a glass bottle and then rapidly cooling the outside whilst slowly cooling the inside. This causes external compression and internal tension such that even a scratch on the inside is sufficient to shatter the bottle.\nThe effect is utilized in several magic effects, including the \"Devil's Flask\".\nManufacture.\nTo create the desired effect, the bottles are rapidly cooled on the outside and slow cooled on the inside during the glass-making process. This causes there to be compressive stress on the outside of the bottle and tensile stress on the inside, making the inside surface susceptible to damage which can release the internal stresses and shatter the bottle. The glass is not annealed. Reheating the glass and then allowing it to cool slowly will remove the unique properties from the glass.\nUses.\nBecause of the seemingly paradoxical nature of the glass (being both extremely durable and extremely fragile), Bologna bottles are often used as props in magic tricks, where the bottle can be shattered by rattling a small object inside it.\nHistory.\nMentioned in the publication of the Royal Society around 1740s, the Bologna bottle is named for where it was first discovered in Bologna, Italy. During this period, a glassblower would create a Bologna bottle by leaving the bottle in the open air instead of immediately placing the bottle back into the furnace to cool (annealing). This produced a special phenomenon, where the bottle would remain intact even when dropped from a distance onto the brick floor, but would immediately rupture if a small piece of flint were placed inside.\nAlthough the bottle can resist a strong external force, the extremely fragile flaws inside the bottle prevent it from being used in practical applications.", "Engineering,_Manufacturing": 0.9982458353, "qwen": "Yes"}
{"id": "26802549", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=26802549", "title": "Lean enterprise", "text": "Lean enterprise is a practice focused on value creation for the end customer with minimal waste and processes. The term has historically been associated with lean manufacturing and Six Sigma (or Lean Six Sigma) due to lean principles being popularized by Toyota in the automobile manufacturing industry and subsequently the electronics and internet software industries.\nPrinciples and variants.\nPrinciples for lean enterprise derive from lean manufacturing and Six Sigma principles:\nThere are five principles, originating from lean manufacturing, outlined by James Womack and Daniel Jones\nThere are key lean enterprise principles originating from Lean Six Sigma principles. These principles focus on eliminating 8 varieties of waste (Muda) and form the acronym Downtime:\nThese 8 varieties of waste are derivative from the original 7 wastes as defined in the Toyota Production System (TPS). They are:\nThe 8th waste of non-utilized talent was not recognized until post-Americanization of the Toyota Production System (TPS).\nThe lean startup principles, developed in 2008 from lean manufacturing, also now contribute to our understanding of lean enterprise:\nHistory.\nEarly 1900s: Ford, GM & Toyota Systems.\nHenry Ford developed a process called assembly line production. This is a manufacturing process in which parts are added as the assembly moves from work station to work station where parts are added in sequence until final assembly is produced.\nAlfred Sloan of General Motors further developed the concept of assembly line production by building a process called mass production that allowed scale and variety. This process enabled large amounts of standardized products to run through assembly lines while still being able to produce more variety and compete against Ford's single offering.\nKiichiro Toyoda studied the Ford production system and adapted the process in order to have smaller production quantities. He built a production system called Just-in-Time Manufacturing for Toyota along with Taiichi Ohno. It's worth noting too that kaizen, the process of continuous improvement, was developed in the 1950s by Eiji Toyoda along with the Toyota Production System (TPS).\n1980s & 1990s: Motorola.\nNew innovations in lean enterprise moved away from machine technology to electronic technology.\nAnother development was management techniques from Motorola commonly referred to as Six Sigma. This management technique was built off of mass production principles with more focus on minimizing variability. Applying Six Sigma principles led to reduced cycle time, reduced pollution, reduced costs, increased customer satisfaction, and increased profits.\n1990s & 2000s: Internet companies.\nNew innovations in lean enterprise moved away from electronic manufacturing to internet and software technology. Before, during, and after the dot-com bubble, internet and software enterprises originally did not place emphasis on lean enterprise principles for efficient usage and allocation of capital and labor due to accessible funds from venture capital and capital markets. The idea of \"build it and they will come\" became common practice as a result.\nAfter the dot-com bubble, inspired by the Agile Manifesto, internet and software companies began operating under agile software development practices such as Extreme programming. Along with the agile software movement, companies (especially startups) applied both lean enterprise and agile software principles together in order to develop new products or even new companies more efficiently and based on validated customer demand. Very early practices of lean enterprise and agile software principles was commonly referred to as lean startup.\nAfter 2010, more and more enterprises are adopting this new branch of lean enterprise (lean startup) since it provides principles and methodologies for non-internet enterprises to enter in new markets or offer goods and services in new form factors with less time, labor, and capital. For internet and software enterprises (by tradition), the Lean startup variant of lean enterprise enabled them to remain competitive with new technologies and services that are rapidly coming out to market without exclusively resorting to mergers and acquisitions, and being able to retain internal innovation ecosystem competency.", "Engineering,_Manufacturing": 0.9999923706, "qwen": "Yes"}
{"id": "55897559", "revid": "36112485", "url": "https://en.wikipedia.org/wiki?curid=55897559", "title": "Rouge and Riches", "text": "Rouge and Riches is a lost 1920 silent film drama directed by Harry L. Franklin. It starred Mary MacLaren. It was produced and distributed by the Universal Film Manufacturing Company.", "Engineering,_Manufacturing": 0.9999995232, "qwen": "Yes"}
{"id": "4714340", "revid": "37102400", "url": "https://en.wikipedia.org/wiki?curid=4714340", "title": "Dicing saw", "text": "A dicing saw is a kind of saw which employs a high-speed spindle fitted with an extremely thin diamond blade or diamond wire to dice, cut, or groove semiconductor wafers, and glass, ceramic, crystal, and many other types of material.\nThe thickness of the cutting blades used varies with the material being cut, and is of about 20 μm to 35 μm when cutting silicon wafers. Japanese companies, such as DISCO Corporation and Accretech (Tokyo Seimitsu), account for about 90% of dicing saw sales. In the past, cutting 1/2 to 2/3 of wafer thickness was the mainstream; with large diameter wafers on dicing tape, full cut cutting is becoming mainstream. ", "Engineering,_Manufacturing": 0.9976714849, "qwen": "Yes"}
{"id": "4719109", "revid": "1171304158", "url": "https://en.wikipedia.org/wiki?curid=4719109", "title": "In-mould labelling", "text": "In-mould labelling is the use of paper or plastic labels during the manufacturing of containers by blow molding, injection molding, or thermoforming processes. The label serves as the integral part of the final product, which is then delivered as pre-decorated item. Combining the decoration process with the moulding process cuts the total cost, but can increase the manufacturing time. The technology was first developed by Owens-Illinois in cooperation with Procter & Gamble to supply pre-labelled bottles that could be filled on the product filling line. This was first applied to Head & Shoulders shampoo bottles.\nPrinciples.\nIn-mould labelling (IML) was initially designed for blow molding, though developments using injection molding or thermoforming with reel-fed systems have increased the efficiency of the labelling process. The original concept involves coating the reverse side of the label with a heat seal layer, followed by a substrate material which heat resistant ink is applied to. A heat resistant coating of lacquer is then applied. This process eliminates the need to flame treat the bottles prior to labelling in order to achieve adequate adhesion. Initially, paper was used as the label substrate to which the heat reactive adhesive was applied. In more recent times polyolefin substrates have been employed, such as Polyart from Arjobex Synthetic Papers. This creates the advantage that scrap polyethylene and polypropylene bottles produced in the molding process can be recycled, without the need for label removal prior to recycling. \nLabelling.\nThere are several techniques for conducting the in-mould labelling process. Vacuum and compressed air can be used to handle the labels, also static electricity can be used. Electrostatic charging electrodes charge a label while it is being transferred to the moulding machine, so that when the label is placed on the tool and released by the labelling robot, it will wrap itself onto the tool. Most robot systems for placement of labels are not required for specific moulding machines and can be used with up to date presses with fast clamping systems.\nLabels may be paper or a similar material to the moulded product. Polypropylene or polystyrene is commonly used as label material, with a thickness of 15 to 40 micrometres. Cavitated label material is also used. This is a sandwich material, having a spongy layer bonded between two very thin solid layers. An advantage of cavitated film is better conformance to small-radius curves on a product. Laminated film can be used to decorate products, yielding high wear-resistance. This type of film has the printed surface protected by a second layer of film, with a thickness of 30 or 40 micrometres. Products using this type of label might include picnic-ware, mouse-mats, or internal automotive components.\nUse.\nIn-mould labelling is a popular method of decorating injection molded parts for consumer electronics and for plastic bottles. Notebook computer and cellphone manufacturers are adopting IML technology for greater wear resistance than spray painting or pad-printing. IML can provide greater decorating options than other methods. Multi-color screen printed and offset lithography printed graphics are used to produce products with higher quality graphics than available with other decorating methods. Most applications in this area use second surface graphics. The decoration is printed on the back side of a clear substrate, typically polycarbonate or acrylic thick. The injection plastic is on the ink side of the film. This encapsulates the decoration between the film layer and the injected plastic resulting in a decoration that cannot be abraded during use. Vision systems can check for accurate label positioning, and can validate label correctness.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "852842", "revid": "3006008", "url": "https://en.wikipedia.org/wiki?curid=852842", "title": "Allard & Co", "text": "Allard & Co. was a British manufacturing company, established in 1889 in Coventry by Frederick W. Allard and George Pilkington as cycle makers.\nIn 1898 the company produced a 3-wheel motorised tricycle together with its first car. Car manufacturing started in 1899.\nIn 1901 the company merged with the Birmingham Motor Manufacturing and Supply Co and was renamed as Rex Motor Manufacturing Co.\nVehicles.\nAllard moved into the motor industry building a four-seater 4½ hp model based on the Benz, followed by a 3 hp air-cooled car with an engine said to be of their own manufacture.\nIn 1902 they offered a 9 hp single-cylinder light car.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "855850", "revid": "237572", "url": "https://en.wikipedia.org/wiki?curid=855850", "title": "Extrusion", "text": "Extrusion is a process used to create objects of a fixed cross-sectional profile by pushing material through a die of the desired cross-section. Its two main advantages over other manufacturing processes are its ability to create very complex cross-sections; and to work materials that are brittle, because the material encounters only compressive and shear stresses. It also creates excellent surface finish and gives considerable freedom of form in the design process.\nDrawing is a similar process, using the tensile strength of the material to pull it through the die. It limits the amount of change that can be performed in one step, so it is limited to simpler shapes, and multiple stages are usually needed. Drawing is the main way to produce wire. Metal bars and tubes are also often drawn.\nExtrusion may be continuous (theoretically producing indefinitely long material) or semi-continuous (producing many pieces). It can be done with hot or cold material. Commonly extruded materials include metals, polymers, ceramics, concrete, modelling clay, and foodstuffs. Products of extrusion are generally called \"extrudates\".\nAlso referred to as \"hole flanging\", hollow cavities within extruded material cannot be produced using a simple flat extrusion die, because there would be no way to support the centre barrier of the die. Instead, the die assumes the shape of a block with depth, beginning first with a shape profile that supports the center section. The die shape then internally changes along its length into the final shape, with the suspended center pieces supported from the back of the die. The material flows around the supports and fuses to create the desired closed shape.\nThe extrusion of metals can also increase their strength.\nHistory.\nIn 1797, Joseph Bramah patented the first extrusion process for making pipe out of soft metals. It involved preheating the metal and then forcing it through a die via a hand-driven plunger. In 1820 Thomas Burr implemented that process for lead pipe, with a hydraulic press (also invented by Joseph Bramah). At that time the process was called \"squirting\". In 1894, Alexander Dick expanded the extrusion process to copper and brass alloys.\nTypes of extrusions.\nThe process begins by heating the stock material (for hot or warm extrusion). It is then loaded into the container in the press. A dummy block is placed behind it where the ram then presses on the material to push it out of the die. Afterward the extrusion is stretched in order to straighten it. If better properties are required then it may be heat treated or cold worked.\nThe extrusion ratio is defined as the starting cross-sectional area divided by the cross-sectional area of the final extrusion. One of the main advantages of the extrusion process is that this ratio can be very large while still producing quality parts.\nHot extrusion.\nHot extrusion is a hot working process, which means it is done above the material's recrystallization temperature to keep the material from work hardening and to make it easier to push the material through the die. Most hot extrusions are done on horizontal hydraulic presses that range from . Pressures range from , therefore lubrication is required, which can be oil or graphite for lower temperature extrusions, or glass powder for higher temperature extrusions. The biggest disadvantage of this process is its cost for machinery and its upkeep.\nThe extrusion process is generally economical when producing between several kilograms (pounds) and many tons, depending on the material being extruded. There is a crossover point where roll forming becomes more economical. For instance, some steels become more economical to roll if producing more than 20,000 kg (50,000 lb).\nCold extrusion.\nCold extrusion is done at room temperature or near room temperature. The advantages of this over hot extrusion are the lack of oxidation, higher strength due to cold working, closer tolerances, better surface finish, and fast extrusion speeds if the material is subject to hot shortness.\nMaterials that are commonly cold extruded include: lead, tin, aluminium, copper, zirconium, titanium, molybdenum, beryllium, vanadium, niobium, and steel.\nExamples of products produced by this process are: collapsible tubes, fire extinguisher cases, shock absorber cylinders and gear blanks.\nWarm extrusion.\nIn March 1956, a US patent was filed for \"process for warm extrusion of metal\". Patent US3156043 A outlines that a number of important advantages can be achieved with warm extrusion of both ferrous and non-ferrous metals and alloys if a billet to be extruded is changed in its physical properties in response to physical forces by being heated to a temperature below the critical melting point. Warm extrusion is done above room temperature, but below the recrystallization temperature of the material the temperatures ranges from 800 to 1,800 °F (424 to 975 °C). It is usually used to achieve the proper balance of required forces, ductility and final extrusion properties.\nFriction extrusion.\nFriction extrusion was invented at the Welding Institute in the UK and patented in 1991. It was originally intended primarily as a method for production of homogeneous microstructures and particle distributions in metal matrix composite materials. Friction extrusion differs from conventional extrusion in that the charge (billet or other precursor) rotates relative to the extrusion die. An extrusion force is applied so as to push the charge against the die. In practice either the die or the charge may rotate or they may be counter-rotating. The relative rotary motion between the charge and the die has several significant effects on the process. First, the relative motion in the plane of rotation leads to large shear stresses, hence, plastic deformation in the layer of charge in contact with and near the die. This plastic deformation is dissipated by recovery and recrystallization processes leading to substantial heating of the deforming charge. Because of the deformation heating, friction extrusion does not generally require preheating of the charge by auxiliary means potentially resulting in a more energy efficient process. Second, the substantial level of plastic deformation in the region of relative rotary motion can promote solid state welding of powders or other finely divided precursors, such as flakes and chips, effectively consolidating the charge (friction consolidation) prior to extrusion.\nMicro-extrusion.\nMicroextrusion is a microforming extrusion process performed at the submillimetre range. Like extrusion, metal is pushed through a die orifice, but the resulting product's cross section can fit through a 1 mm square. Several microextrusion processes have been developed since microforming was envisioned in 1990. Forward (ram and billet move in the same direction) and backward (ram and billet move in the opposite direction) microextrusion were first introduced, with forward rod-backward cup and double cup extrusion methods developing later. Regardless of method, one of the greatest challenges of creating a successful microextrusion machine is the manufacture of the die and ram. \"The small size of the die and ram, along with the stringent accuracy requirement, needs suitable manufacturing processes.\" Additionally, as Fu and Chan pointed out in a 2013 state-of-the-art technology review, several issues must still be resolved before microextrusion and other microforming technologies can be implemented more widely, including deformation load and defects, forming system stability, mechanical properties, and other size-related effects on the crystallite (grain) structure and boundaries.\nEquipment.\nThere are many different variations of extrusion equipment. They vary by four major characteristics:\nA single or twin screw auger, powered by an electric motor, or a ram, driven by hydraulic pressure (often used for steel and titanium alloys), oil pressure (for aluminium), or in other specialized processes such as rollers inside a perforated drum for the production of many simultaneous streams of material.\nTypical extrusion presses cost more than $100,000, whereas dies can cost up to $2,000.\nForming internal cavities.\nThere are several methods for forming internal cavities in extrusions. One way is to use a hollow billet and then use a fixed or floating mandrel. A fixed mandrel, also known as a German type, means it is integrated into the dummy block and stem. A floating mandrel, also known as a French type, floats in slots in the dummy block and aligns itself in the die when extruding. If a solid billet is used as the feed material then it must first be pierced by the mandrel before extruding through the die. A special press is used in order to control the mandrel independently from the ram. The solid billet could also be used with a spider die, porthole die or bridge die. All of these types of dies incorporate the mandrel in the die and have \"legs\" that hold the mandrel in place. During extrusion the metal divides, flows around the legs, then merges, leaving weld lines in the final product.\nDirect extrusion.\nDirect extrusion, also known as forward extrusion, is the most common extrusion process. It works by placing the billet in a heavy walled container. The billet is pushed through the die by a ram or screw. There is a reusable dummy block between the ram and the billet to keep them separated. The major disadvantage of this process is that the force required to extrude the billet is greater than that needed in the indirect extrusion process because of the frictional forces introduced by the need for the billet to travel the entire length of the container. Because of this the greatest force required is at the beginning of process and slowly decreases as the billet is used up. At the end of the billet the force greatly increases because the billet is thin and the material must flow radially to exit the die. The end of the billet (called the butt end) is not used for this reason.\nIndirect extrusion.\nIn indirect extrusion, also known as backwards extrusion, the billet and container move together while the die is stationary. The die is held in place by a \"stem\" which has to be longer than the container length. The maximum length of the extrusion is ultimately dictated by the column strength of the stem. Because the billet moves with the container the frictional forces are eliminated. This leads to the following advantages:\nThe disadvantages are:\nHydrostatic extrusion.\nIn the hydrostatic extrusion process the billet is completely surrounded by a pressurized liquid, except where the billet contacts the die. This process can be done hot, warm, or cold, however the temperature is limited by the stability of the fluid used. The process must be carried out in a sealed cylinder to contain the hydrostatic medium. The fluid can be pressurized two ways:\nThe advantages of this process include:\nThe disadvantages are:\nDrives.\nMost modern direct or indirect extrusion presses are hydraulically driven, but there are some small mechanical presses still used. Of the hydraulic presses there are two types: direct-drive oil presses and accumulator water drives.\nDirect-drive oil presses are the most common because they are reliable and robust. They can deliver over 35 MPa (5,000 psi). They supply a constant pressure throughout the whole billet. The disadvantage is that they are slow, between 50 and 200 mm/s (2–8 ips).\nAccumulator water drives are more expensive and larger than direct-drive oil presses, and they lose about 10% of their pressure over the stroke, but they are much faster, up to 380 mm/s (15 ips). Because of this they are used when extruding steel. They are also used on materials that must be heated to very hot temperatures for safety reasons.\nHydrostatic extrusion presses usually use castor oil at pressure up to 1,400 MPa (200 ksi). Castor oil is used because it has good lubricity and high pressure properties.\nDie design.\nThe design of an extrusion profile has a large impact on how readily it can be extruded. The maximum size for an extrusion is determined by finding the smallest circle that will fit around the cross-section, this is called the \"circumscribing circle\". This diameter, in turn, controls the size of the die required, which ultimately determines if the part will fit in a given press. For example, a larger press can handle diameter circumscribing circles for aluminium and 55 cm (22 in) diameter circles for steel and titanium.\nThe complexity of an extruded profile can be roughly quantified by calculating the \"shape factor\", which is the amount of surface area generated per unit mass of extrusion. This affects the cost of tooling as well as the rate of production.\nThicker sections generally need an increased section size. In order for the material to flow properly legs should not be more than ten times longer than their thickness. If the cross-section is asymmetrical, adjacent sections should be as close to the same size as possible. Sharp corners should be avoided; for aluminium and magnesium the minimum radius should be 0.4 mm (1/64 in) and for steel corners should be and fillets should be . The following table lists the minimum cross-section and thickness for various materials.\nMaterials.\nMetal.\nMetals that are commonly extruded include:\nMagnesium and aluminium alloys usually have a RMS or better surface finish. Titanium and steel can achieve a RMS.\nIn 1950, Ugine Séjournet, of France, invented a process which uses glass as a lubricant for extruding steel. The Ugine-Sejournet, or Sejournet, process is now used for other materials that have melting temperatures higher than steel or that require a narrow range of temperatures to extrude, such as the platinum-iridium alloy used to make kilogram mass standards. The process starts by heating the materials to the extruding temperature and then rolling it in glass powder. The glass melts and forms a thin film, 20 to 30 mils (0.5 to 0.75 mm), in order to separate it from chamber walls and allow it to act as a lubricant. A thick solid glass ring that is 0.25 to 0.75 in (6 to 18 mm) thick is placed in the chamber on the die to lubricate the extrusion as it is forced through the die. A second advantage of this glass ring is its ability to insulate the heat of the billet from the die. The extrusion will have a 1 mil thick layer of glass, which can be easily removed once it cools.\nAnother breakthrough in lubrication is the use of phosphate coatings. With this process, in conjunction with glass lubrication, steel can be cold extruded. The phosphate coat absorbs the liquid glass to offer even better lubricating properties.\nPlastic.\nPlastics extrusion commonly uses plastic chips or pellets, which are usually dried, to drive out moisture, in a hopper before going to the feed screw. The polymer resin is heated to molten state by a combination of heating elements and shear heating from the extrusion screw. The screw, or screws as the case with twin screw extrusion, forces the resin through a die, forming the resin into the desired shape. The extrudate is cooled and solidified as it is pulled through the die or water tank. A \"caterpillar haul-off\" (called a \"puller\" in the US) is used to provide tension on the extrusion line which is essential for overall quality of the extrudate. Pelletizers can also create this tension while pulling extruded strands in to be cut. The caterpillar haul-off must provide a consistent pull; otherwise, variation in cut lengths or distorted product will result. In some cases (such as fibre-reinforced tubes) the extrudate is pulled through a very long die, in a process called \"pultrusion\". The configuration of the interior screws are a driving force dependent on the application. Mixing elements or convey elements are used in various formations. Extrusion is common in the application of adding colorant to molten plastic thus creating specific custom color.\nA multitude of polymers are used in the production of plastic tubing, pipes, rods, rails, seals, and sheets or films.\nRubber.\nRubber extrusion is a method used to make rubber items. In this process, either synthetic or natural rubber that hasn't been hardened yet is put through a machine called an extruder. This machine has a desired shaped mold and a pressurized conveyor system. The rubber gets heated and softened in the extruder, making it bendable. It then gets pushed through the mold, which gives it its final shape.\nThe extruder consists of two main parts: a screw that moves the rubber along the conveyor while adding other materials, and a mold where the soft rubber is squeezed into. After the rubber gets its shape from the mold, it is then vulcanized to harden it into a usable product.\nThis method is great for making large rubber pieces that are long and have a consistent shape. The molds used in this process are not too costly. This is often used to make things like rubber seals or hoses.\nCeramic.\nCeramic can also be formed into shapes via extrusion. Terracotta extrusion is used to produce pipes. Many modern bricks are also manufactured using a brick extrusion process.\nApplications.\nFood.\nWith the advent of industrial manufacturing, extrusion found application in food processing of instant foods and snacks, along with its already known uses in plastics and metal fabrication. The main role of extrusion was originally developed for conveying and shaping fluid forms of processed raw materials. Present day, extrusion cooking technologies and capabilities have developed into sophisticated processing functions including: mixing, conveying, shearing, separation, heating, cooling, shaping, co-extrusion, venting volatiles and moisture, encapsulation, flavor generation and sterilization. Products such as certain pastas, many breakfast cereals, premade cookie dough, some french fries, certain baby foods, dry or semi-moist pet food and ready-to-eat snacks are mostly manufactured by extrusion. It is also used to produce modified starch, and to pelletize animal feed.\nGenerally, high-temperature extrusion is used for the manufacture of ready-to-eat snacks, while cold extrusion is used for the manufacture of pasta and related products intended for later cooking and consumption. The processed products have low moisture and hence considerably higher shelf life, and provide variety and convenience to consumers.\nIn the extrusion process, raw materials are first ground to the correct particle size. The dry mix is passed through a pre-conditioner, in which other ingredients may be added, and steam is injected to start the cooking process. The preconditioned mix is then passed through an extruder, where it is forced through a die and cut to the desired length. The cooking process takes place within the extruder where the product produces its own friction and heat due to the pressure generated (10–20 bar). The main independent parameters during extrusion cooking are feed rate, particle size of the raw material, barrel temperature, screw speed and moisture content. The extruding process can induce both protein denaturation and starch gelatinization, depending on inputs and parameters. Sometimes, a catalyst is used, for example, when producing texturised vegetable proteins (TVP).\nDrug carriers.\nFor use in pharmaceutical products, extrusion through nano-porous, polymeric filters is being used to produce suspensions of lipid vesicles liposomes or transfersomes with a particular size of a narrow size distribution. The anti-cancer drug Doxorubicin in liposome delivery system is formulated by extrusion, for example. Hot melt extrusion is also utilized in pharmaceutical solid oral dose processing to enable delivery of drugs with poor solubility and bioavailability. Hot melt extrusion has been shown to molecularly disperse poorly soluble drugs in a polymer carrier increasing dissolution rates and bioavailability. The process involves the application of heat, pressure and agitation to mix materials together and ‘extrude’ them through a die. Twin-screw high shear extruders blend materials and simultaneously break up particles. The resulting particle can be blended with compression aids and compressed into tablets or filled into unit dose capsules.\nBiomass briquettes.\nThe extrusion production technology of fuel briquettes is the process of extrusion screw wastes (straw, sunflower husks, buckwheat, etc.) or finely shredded wood waste (sawdust) under high pressure when heated from 160 to 350 °C. The resulting fuel briquettes do not include any of the binders, but one natural – the lignin contained in the cells of plant wastes. The temperature during compression causes melting of the surface of bricks, making it more solid, which is important for the transportation of briquettes.\nTextiles.\nThe majority of synthetic materials in textiles are manufactured with extrusion only. Fiber forming substances are used in extrusion to form various synthetic filaments. The molten materials are passed through a spinneret that helps in forming fibers.", "Engineering,_Manufacturing": 0.9999916553, "qwen": "Yes"}
{"id": "1399085", "revid": "4662644", "url": "https://en.wikipedia.org/wiki?curid=1399085", "title": "Methods engineering", "text": "Methods engineering is a subspecialty of industrial engineering and manufacturing engineering concerned with human integration in industrial production processes.\nOverview.\nAlternatively it can be described as the design of the productive process in which a person is involved. The task of the Methods engineer is to decide where humans will be utilized in the process of converting raw materials to finished products and how workers can most effectively perform their assigned tasks. The terms operation analysis, work design and simplification, and methods engineering and corporate re-engineering are frequently used interchangeably.\nLowering costs and increasing reliability and productivity are the objectives of methods engineering. Methods efficiency engineering focuses on lowering costs through productivity improvement. It investigates the output obtained from each unit of input and the speed of each machine and man. Methods quality engineering focuses on increasing quality and reliability. These objectives are met in a five step sequence as follows: Project selection, data acquisition and presentation, data analysis, development of an ideal method based on the data analysis and, finally, presentation and implementation of the method.\nMethods engineering topics.\nProject selection.\nMethods engineers typically work on projects involving new product design, products with a high cost of production to profit ratio, and products associated with having poor quality issues. Different methods of project selection include the Pareto analysis, fish diagrams, Gantt charts, PERT charts, and job/work site analysis guides.\nData acquisition and presentation.\nData that needs to be collected are specification sheets for the product, design drawings, process plans, quantity and delivery requirements, and projections as to how the product will perform or has performed in the market. Process charts are used to describe proposed or existing way of doing work utilizing machines and men. The Gantt process chart can assist in the analysis of the man to machine interaction and it can aid in establishing the optimum number of workers and machines subject to the financial constraints of the operation. A flow diagram is frequently employed to represent the manufacturing process associated with the product.\nData analysis.\nData analysis enables the methods engineer to make decisions about several things, including: purpose of the operation, part design characteristics, specifications and tolerances of parts, materials, manufacturing process design, setup and tooling, working conditions, material handling, plant layout, and workplace design. Knowing the specifics (who, what, when, where, why, and how) of product manufacturing assists in the development of an optimum manufacturing method.\nIdeal method development.\nEquations of synchronous and random servicing as well as line balancing are used to determine the ideal worker to machine ratio for the process or product chosen. Synchronous servicing is defined as the process where a machine is assigned to more than one operator, and the assigned operators and machine are occupied during the whole operating cycle. Random servicing of a facility, as the name indicates, is defined as a servicing process with a random time of occurrence and need of servicing variables. Line balancing equations determine the ideal number of workers needed on a production line to enable it to work at capacity.\nPresentation and methods implementation.\nThe industrial process or operation can be optimized using a variety of available methods. Each method design has its advantages and disadvantages. The best overall method is chosen using selection criteria and concepts involving value engineering, cost-benefit analysis, crossover charts, and economic analysis. The outcome of the selection process is then presented to the company for implementation at the plant. This last step involves \"selling the idea\" to the company brass, a skill the methods engineer must develop in addition to the normal engineering qualifications.", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "31794108", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=31794108", "title": "Carbon nanotube metal matrix composite", "text": "Carbon nanotube metal matrix composites (CNT-MMC) are an emerging class of new materials that mix carbon nanotubes into metals and metal alloys to take advantage of the high tensile strength and electrical conductivity of carbon nanotube materials.\nCarbon nanotubes reinforced metal matrix composites production methods.\nCNT-MMCs may be produced in several different methods. These production methods include, but are not limited to, various powder metallurgy techniques such as hot pressing, hot extrusion, semisolid powder processing, thermal spraying, sputtering, physical vapor deposition, and pulsed laser deposition.\nPowder metallurgy techniques.\nConventional sintering is the simplest method for producing CNT metal matrix composite compacts. The CNTs and metal powders are mixed by a process of mechanical alloying/blending and then are compressed to form a green compact, which is then sintered to get the final product. Metallic compacts are subject to oxidation as compared to ceramics and hence the sintering has to be done in an inert atmosphere or under vacuum. One major drawback of this processing route is the inability to tailor the CNT distribution within the metallic matrix.\nMicrowave sintering is one of them and fundamentally different from conventional sintering. In microwave sintering process, the material is heated internally and volumetrically unlike in a conventional process where heat originates from an external heating source. Sintering cycle time for microwave sintering is much shorter as compared with the conventional sintering cycle.\nSpark plasma sintering is a technique which takes only a few minutes to complete a sintering process compared to conventional sintering which may take hours or even days for the same. High sintering rate is possible in SPS since high heating rates can be easily attained due to internal heating of the sample as opposed to external heating seen in case of conventional sintering. For conventional sintering usually a green compact needs to be prepared externally using a suitable die and hydraulic machine for applying the necessary pressure. In SPS the powder is directly fed into the graphite dies and the die is enclosed with suitable punches. All types of materials, even those difficult to densify can be easily sintered in SPS. Due to advantage of high heating rate and less holding time, SPS can restrict the unwanted sintering reactions in highly reactive systems as opposed to conventional sintering and hence formation of undesirable product phases can be avoided.\nSemi-solid powder processing is a unique method that fabricates composites materials with powder mixtures in the semi-solid states. Starting with metal-CNT powder mixture, the metal powder is heated to the semi-solid state, and pressure is applied to form the metal matrix composites. This method features many advantages such as simple and fast process and flexible property tailoring.\nCarbon nanotube dispersing and CNT breakage during mixing.\nOne common method to disperse the CNT into the metal matrix is mechanical alloying. However, many researchers reported the length reduction and damage of CNTs during mechanical alloying process.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "31796207", "revid": "5718152", "url": "https://en.wikipedia.org/wiki?curid=31796207", "title": "Pro Mach", "text": "Pro Mach, Inc. (also referred to as ProMach) is a packaging machinery company headquartered in Covington, Kentucky. It was founded in 1998 and is a member of The Association for Packaging and Processing Technologies (PMMI).\nThe firm provides integrated packaging products and machinery for the food, beverage, household goods and pharmaceutical industries. ProMach has 61 manufacturing facilities, 29 sales and support offices, and 46 go-to-market product brands that offer packaging machinery, food processing machinery, label manufacturing, film manufacturing, plastic parts manufacturing, equipment training, and aftermarket parts and service. Its manufacturing facilities and offices are located throughout North America, Europe, South America, and Asia.\nProMach has been listed nine times on the Inc. 5000, which ranks America's fastest-growing private companies. ProMach most recently ranked No. 4,076 on the 2013 list, ranked No. 4,058 on the 2014 list, ranked No. 4,014 on the 2015 list, ranked No. 4,589 on the 2016 list, ranked No. 4,269 on the 2017 list, ranked No. 4,927 on the 2018 list, and ranked No. 4,493 on the 2019 list. ProMach has also been listed eighteen times on the Deloitte Cincinnati USA 100, which ranks the 100 largest privately held companies in Greater Cincinnati and Northern Kentucky. ProMach most recently ranked No. 32 on the 2012 list, ranked No. 30 on the 2013 list, ranked No. 29 on the 2014 list, ranked No. 24 on the 2015 list, ranked No. 23 on the 2016 list, ranked No. 20 on the 2017 list, ranked No. 14 on the 2018 list, ranked No. 14 on the 2019 list, ranked No. 13 on the 2020 list, ranked No. 11 on the 2021 list, ranked No. 9 on the 2022 list, and ranked No. 9 on the 2023 list. It received the 2010 Manny Green Award from Cincy magazine for manufacturing initiatives and product innovations that helped customers improve package sustainability.\nOn May 3, 2023 it was announced that funds managed by BDT Capital Partners have entered into a definitive agreement to acquire a significant stake in ProMach alongside Leonard Green & Partners, the existing majority owner. On August 1, 2023, the acquisition of ProMach by Affiliates of BDT Capital Partners and Affiliates of Leonard Green & Partners, L.P. was completed. Financial terms of the transaction were not disclosed.\nProMach was formerly owned by Leonard Green & Partners, L.P., AEA Investors LP, The Jordan Company, Odyssey Investment Partners, LLC, and the Frontenac Company.\nProMach Product Brands.\nThe following is a list of trademarked ProMach product brands that provide equipment and services:\nHistory.\nJuly 1998\nPro Mach, Inc. was founded by Frontenac Company and headquarters were set up in Atlanta, Georgia. JP Richard named President and CEO.\nNovember 1998\nProMach acquired Wexxar Packaging of Delta, British Columbia, Canada, provider of case erecting, case forming, and case sealing machinery.\nDecember 1998\nProMach acquired Brenton Engineering of Alexandria, Minnesota, provider of case packing, shrink wrapping, and palletizing machinery.\nProMach also acquired Roberts PolyPro of Charlotte, North Carolina, provider of plastic handles, product merchandising hooks and paperboard finishing/converting machinery.\nMarch 1999\nProMach acquired Axon of Raleigh, North Carolina, provider of heat shrink sleeve and tamper evident band application machinery.\nJune 1999\nProMach acquired Orion Packaging of Collierville, Tennessee, provider of stretch wrapping and pallet wrapping machinery.\nProMach also acquired Styrotech of Raleigh, North Carolina, provider of stretch sleeve application machinery, to expand Axon's product line offerings.\nJuly 1999\nProMach acquired Ossid of Rocky Mount, North Carolina, provider of tray overwrapping machinery.\nJanuary 2000\nProMach acquired Belcor Industries of Richmond, British Columbia, Canada, provider of case forming and case taping machinery.\nMarch 2000\nProMach acquired Rennco of Homer, Michigan, provider of vertical bagging and l-bar sealing machinery.\nAugust 2000\nProMach acquired Robot Aided Manufacturing (RAM) Center of Red Wing, Minnesota, provider of robotic packaging machinery, to expand Brenton's product line offerings.\nNovember 2000\nProMach acquired Fowler Products Company of Athens, Georgia, provider of bottle capping and bottle cap handling machinery.\nOctober 2002\nProMach acquired ID Technology of Fort Worth, Texas, provider of label application, coding, and marking machinery as well as consumable labels.\nDecember 2004\nOdyssey Investment Partners acquired ProMach from Frontenac Company and headquarters were moved to Loveland, Ohio. John W. Paxton, Sr. named Chairman and CEO.\nApril 2005\nBill M. Schult named CFO of ProMach.\nAugust 2005\nMark W. Anderson named President and COO of ProMach.\nJanuary 2006\nProMach acquired the Robocaser product line from Mettler-Toledo Hi-Speed to expand Brenton's product line offerings.\nFebruary 2006\nProMach acquired Mahaffy & Harder Engineering of Fairfield, New Jersey, provider of horizontal thermoform, fill, seal and tray sealing machinery, to expand Ossid's product line offerings.\nMay 2006\nProMach acquired The Glennon Group of Milwaukee, Wisconsin, provider of labeling, marking, and packaging systems, to expand ID Technology's regional operations into the Midwest.\nProMach also acquired Allpax Products of Covington, Louisiana, provider of retort and sterilization machinery.\nSeptember 2006\nProMach acquired Currie Machinery Company, provider of palletizing and material handling machinery, to expand Brenton's product line offerings.\nMay 2007\nProMach acquired Markor Marking and Labeling Systems of Fresno, California, provider of labeling and identification products, to expand ID Technology's regional operations into the Western United States.\nMarch 2008\nProMach acquired Labeling Systems (LSI) of Oakland, New Jersey, provider of pressure-sensitive labeling machinery.\nApril 2008\nMark W. Anderson named President and CEO of ProMach.\nJune 2009\nProMach acquired IPak Machinery of Vancouver, British Columbia, Canada, provider of corrugated tray forming machinery, to expand Wexxar's product line offerings.\nOctober 2009\nProMach launches ProCustomer brand to focus on branded packaging machinery customer service.\nJanuary 2011\nProMach acquired Shuttleworth of Huntington, Indiana, provider of conveyor automation and product handling machinery.\nJuly 2011\nThe Jordan Company acquired ProMach from Odyssey Investment Partners. The ProMach management team will remain intact.\nOctober 2011\nProMach acquired Matrix Packaging Machinery of Saukville, Wisconsin, provider of vertical form fill seal packaging machinery.\nFebruary 2012\nProMach acquired Edson Packaging Machinery of Hamilton, Ontario, Canada, provider of case and tray packaging machinery.\nAugust 2012\nProMach acquired Federal Manufacturing Co of Milwaukee, Wisconsin, provider of liquid bottle filling and capping machinery.\nDecember 2012\nProMach acquired KLEENLine of Newburyport, Massachusetts, provider of sanitary product and material handling and automation machinery.\nProMach also acquired Logmatix of Marietta, Georgia, provider of labeling and identification products, to expand ID Technology's regional operations in the Southeast.\nJuly 2013\nProMach acquired Colet of Toronto, Ontario, Canada, provider of labeling and identification products, to expand ID Technology's regional operations in Canada.\nProMach also acquired the assets of Packaging Synergies of Lancaster, Pennsylvania, provider of flexible packaging machinery.\nProMach also acquired Winco ID of Nashua, New Hampshire, provider of labeling and identification products, to expand ID Technology's regional operations in the Northeast.\nNovember 2013\nProMach acquired the assets of Tekkra Systems of Romeoville, Illinois, provider of shrink wrapping and shrink bundling machinery.\nJanuary 2014\nProMach acquired André Zalkin of Montreuil L’Argillé, France, provider of bottle capping and bottle cap handling machinery.\nSeptember 2014\nProMach acquired Benchmark Automation of Athens, Georgia, provider of specialty food and bakery material handling and automation machinery.\nProMach also acquired Pace Packaging of Fairfield, New Jersey, provider of bottle unscrambling and orienting machinery.\nOctober 2014\nAffiliates of AEA Investors LP acquired ProMach from The Jordan Company. The ProMach management team will remain intact.\nSeptember 2015\nProMach acquired Greydon of York, Pennsylvania, provider of flexible packaging coding machinery.\nOctober 2015\nPat M. Mohan named CAO of ProMach.\nJanuary 2016\nProMach acquired EPI Labelers of New Freedom, Pennsylvania, provider of flexible packaging labeling machinery.\nFebruary 2016\nProMach acquired Texwrap Packaging Systems of Washington, Missouri, provider of shrink wrapping machinery.\nMay 2016\nProMach acquired NJM Packaging of Montreal, Quebec, Canada, provider of pharmaceutical and integrated packaging line machinery.\nJuly 2016\nProMach acquired Zarpac of Oakville, Ontario, Canada, provider of packaging line engineering, integration, and productivity services.\nSeptember 2016\nProMach acquired Pacific Packaging of San Clemente, California, provider of rotary and inline bottle filling and capping machinery.\nJanuary 2017\nProMach acquired Jalbert Automatisation of Montreal, Quebec, Canada, provider of packaging automation services.\nJanuary 2017\nProMach has been named as one of the companies as finalists for its prestigious annual Deal Maker Awards by The Association for Corporate Growth's Cincinnati chapter\nApril 2017\nProMach acquired Weiler Labeling Systems of Moorestown, New Jersey, provider of high-speed rotary labeling, serialization, and coding machinery.\nMay 2017\nProMach acquired P.E. Labellers SpA of Porto Mantovano, Italy, provider of high-speed rotary and linear decorative labeling machinery.\nSeptember 2017\nProMach launched an updated brand platform consisting of new corporate and product brand logos, as well as updated messaging.\nFebruary 2018\nAndy W. Moeder named CFO of ProMach.\nMarch 2018\nAffiliates of Leonard Green & Partners, L.P. acquired ProMach from affiliates of AEA Investors LP. The ProMach management team will remain intact.\nSeptember 2018\nProMach acquired FLtècnics of Girona, Spain, provider of horizontal form fill seal pouch packaging machinery.\nFebruary 2019\nProMach acquired Code Tech of Princeton, New Jersey, provider of coding and marking products.\nApril 2019\nProMach acquired Quest Industrial of Monroe, Wisconsin, provider of robotic integration machinery.\nJune 2019\nProMach acquired Stock America of Garner, North Carolina, provider of retort and sterilization machinery.\nOctober 2019\nProMach acquired Grip-Pak of Lake Forest, Illinois, provider of multipack can handles.\nProMach also acquired Jet Label and Jet Marking Systems of Edmonton, Alberta, Canada, provider of labeling and identification products, to expand ID Technology's regional operations in Western Canada.\nJanuary 2020\nBret C. Ranc named COO of ProMach.\nMarch 2020\nProMach acquired Pharmaworks of Odessa, Florida, provider of blister packaging machinery.\nJuly 2020\nProMach acquired Modern Packaging of Deer Park, New York, provider of cup and tray filling machinery.\nAugust 2020\nProMach acquired Fogg Filler of Holland, Michigan, provider of rotary liquid filling machinery.\nSeptember 2020\nProMach acquired Panther Industries of Highlands Ranch, Colorado, provider of print and apply labeling machinery.\nOctober 2020\nProMach acquired Statco-DSI of Huntington Beach, California, provider of processing machinery, engineering, and integration services.\nJanuary 2021\nProMach acquired Bartelt of Sarasota, Florida, provider of horizontal form fill seal packaging machinery.\nFebruary 2021\nProMach acquired Serpa Packaging of Visalia, California, provider of cartoning machinery.\nNovember 2021\nProMach acquired CL&D Graphics and CL&D Digital of Hartland, Wisconsin, provider of flexible packaging, labeling, and identification products.\nFebruary 2022\nProMach acquired TechniBlend and ProBrew of Waukesha, Wisconsin, provider of liquid processing machinery and integration services.\nJune 2022\nProMach acquired Reepack of Seriate, Italy, provider of flexible film and tray packaging machinery.\nNovember 2022\nProMach acquired Ferlo of San Adrián, Spain, provider of retort and sterilization machinery.\nAugust 2023\nAffiliates of BDT Capital Partners and Affiliates of Leonard Green & Partners, L.P. finalized its new ownership agreement with ProMach. The ProMach management team will remain intact.", "Engineering,_Manufacturing": 0.9978075027, "qwen": "Yes"}
{"id": "31801718", "revid": "33584806", "url": "https://en.wikipedia.org/wiki?curid=31801718", "title": "Lamina emergent mechanism", "text": "Lamina Emergent Mechanisms (also known as LEMs) are more commonly referred to as \"Pop-up Mechanisms\" as seen in \"pop-up-books\". LEM is the technical term of such mechanisms or engineering. LEMs are a subset of compliant mechanisms fabricated from planar materials (lamina) and have motion emerging from the fabrication plane. LEMs use compliance, or the deflection of flexible members to achieve motion.\nBackground.\nOrtho-Planar Mechanisms are an earlier concept similar to LEMs. More well known LEMs include pop-up books, flat-folding origami mechanisms, origami stents, and deployable mechanisms. The research in LEMs also overlaps with deployable structures, origami, kirigami, compliant mechanisms, microelectromechanical systems, packaging engineering, robotics, paper engineering, developable mechanisms, and more.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "31802451", "revid": "5042921", "url": "https://en.wikipedia.org/wiki?curid=31802451", "title": "Reaction bonded silicon carbide", "text": "Reaction bonded silicon carbide, also known as siliconized silicon carbide or SiSiC, is a type of silicon carbide that is manufactured by a chemical reaction between porous carbon or graphite with molten silicon. Due to the left over traces of silicon, reaction bonded silicon carbide is often referred to as siliconized silicon carbide, or its abbreviation SiSiC.\nIf pure silicon carbide is produced by sintering of silicon carbide powder, it usually contains traces of chemicals called \"sintering aids\", which are added to support the sintering process by allowing lower sintering temperatures. This type of silicon carbide is often referred to as \"sintered silicon carbide\", or abbreviated to SSiC.\nThe silicon carbide powder is gained from silicon carbide produced as described in the article silicon carbide.", "Engineering,_Manufacturing": 0.9916189313, "qwen": "Yes"}
{"id": "34952856", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=34952856", "title": "2012 NRL Under-20s season results", "text": "This article details scores and results from the 2012 NRL Under-20s season.\nRegular season.\nRound 1.\n\"Source: Round 1 summary - rleague.com\"\nRound 2.\n\"Source: Round 2 summary - rleague.com\"\nRound 3.\n\"Source: Round 3 summary - rleague.com\"\nRound 4.\n\"Source: Round 4 summary - rleague.com\"\nRound 5.\n\"Source: Round 5 summary - rleague.com\"\nRound 6.\n\"Source: Round 6 summary - rleague.com\"\nRound 7.\n\"Source: Round 7 summary - rleague.com\"\nRound 8.\n\"Source: Round 8 summary - rleague.com\"\nRound 9.\n\"Source: Round 9 summary - rleague.com\"\nRound 10.\n\"Source: Round 10 summary - rleague.com\"\nRound 11.\n\"Source: Round 11 summary - rleague.com\"\nRound 12.\n\"Source: Round 12 summary - rleague.com\"\nRound 13.\n\"Source: Round 13 summary - rleague.com\"\nRound 14.\n\"Source: Round 14 summary - rleague.com\"\nRound 15.\n\"Source: Round 15 summary - rleague.com\"\nRound 16.\n\"Source: Round 16 summary - rleague.com\"\nRound 17.\n\"Source: Round 17 summary - rleague.com\"\nRound 18.\n\"Source: Round 18 summary - rleague.com\"\nRound 19.\n\"Source: Round 19 summary - rleague.com\"\nRound 20.\n\"Source: Round 20 summary - rleague.com\"", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "49651549", "revid": "19921271", "url": "https://en.wikipedia.org/wiki?curid=49651549", "title": "Ibiden", "text": " is a Japanese electronics company headquartered in Ogaki, Gifu prefecture that manufactures electronics-related products, such as printed circuit boards and IC packaging. The company also makes ceramics products, including particulate filters for diesel engines, for which it has a 50% market share in Europe.\nIbiden was founded as an electrical power generation company in 1912. In the following decades the company diversified its operations and products, from power generation to electric furnace products (between 1917 and 1919), building materials (in 1960), printed circuit board (in 1972) and ceramic fibers (in 1974).\nToday electronic components and ceramics are the company's main products, with customers including Apple Inc., Intel and Groupe PSA (PSA Peugeot Citroën).", "Engineering,_Manufacturing": 0.9999052286, "qwen": "Yes"}
{"id": "4223085", "revid": "1139474421", "url": "https://en.wikipedia.org/wiki?curid=4223085", "title": "Gear shaper", "text": "A gear shaper is a machine tool for cutting the teeth of internal or external gears, it is a specialised application of the more general shaper machine. The name shaper relates to the fact that the cutter engages the part on the forward stroke and pulls away from the part on the return stroke, just like the clapper box on a planer shaper.\nThe cutting tool is also gear shaped having the same pitch as the gear to be cut. However number of cutting teeth must be less than that of the gear to be cut for internal gears. For external gears the number of teeth on the cutter is limited only by the size of the shaping machine.\nThe principal motions involved in rotary gear shaper cutting are of the following :", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "652102", "revid": "1068029036", "url": "https://en.wikipedia.org/wiki?curid=652102", "title": "Corner case", "text": "In engineering, a corner case (or pathological case) involves a problem or situation that occurs only outside normal operating parameters—specifically one that manifests itself when multiple environmental variables or conditions are simultaneously at extreme levels, even though each parameter is within the specified range for that parameter.\nFor example, a loudspeaker might distort audio, but only when played at maximum volume, maximum bass, and in a high-humidity environment. Or a computer server may be unreliable, but only with the maximum complement of 64 processors, 512 GB of memory, and 10,000 signed-on users. The investigation of corner cases is of extreme importance as it can provide engineers with valuable insight into how corner case effects can be mitigated. In the case where automotive radar fails, corner case investigation can possibly tell engineers and investigators alike what may have occurred.\nCorner cases form part of an engineer's lexicon—especially an engineer involved in testing or debugging a complex system. Corner cases are often harder and more expensive to reproduce, test, and optimize because they require maximal configurations in multiple dimensions. They are frequently less-tested, given the belief that few product users will, in practice, exercise the product at multiple simultaneous maximum settings. Expert users of systems therefore routinely find corner case anomalies, and in many of these, errors.\nThe term \"corner case\" comes about by physical analogy with \"edge case\" as an extension of the \"flight envelope\" metaphor to a set of testing conditions whose boundaries are determined by the 2n combinations of extreme (minimum and maximum) values for the number \"n\" of variables being tested, \"i.e.\", the total parameter space for those variables. Where an edge case involves pushing one variable to a minimum or maximum, putting users at the \"edge\" of the configuration space, a corner case involves doing so with multiple variables, which would put users at a \"corner\" of a multidimensional configuration space.", "Engineering,_Manufacturing": 0.9853505492, "qwen": "Yes"}
{"id": "10189308", "revid": "35393771", "url": "https://en.wikipedia.org/wiki?curid=10189308", "title": "Makino", "text": ", commonly known as Makino, is a machine tool builder with global sales and service, headquartered in Japan.\nHistory.\nMakino was established in 1937 by Tsunezo Makino in Japan, developing Japan's first numerically controlled (NC) milling machine in 1958 and Japan's first machining centre in 1966.\nThe North American branch of Makino was formed through the 1981 merger of the R. K. LeBlond Machine Tool Company of Cincinnati and the Makino Milling Machine Company of Japan. Resulting from the merger was the formation of what was then called \"LeBlond Makino Machine Tool Company\".\nIn 1996, LeBlond Makino became Makino, and in 1997 LeBlond Lathe Ltd. was formed as a parts and servicing subsidiary.\nInnovations.\nIn 1984, Makino introduced the first commercial high-speed spindle for milling. In 1990, Makino introduced Geometric Intelligence, the first servo-control software tailored to high-speed machining, and Flush Fine machining, a method for cutting hardened materials.\nThe company developed the first drop-tank wire EDM in 1994, and HQSF (High-Quality Surface Finish) technology with patented uSc additive in 1996, increasing the ability to finish parts without hand polishing when using a ram EDM. In 2003, Makino developed the first conventional horizontal wire EDM that automatically threads and machines with a 0.02mm diameter wire.\nIn 2006, the company developed High Energy Applied Technology (HEAT) for wire EDMs to increase speed in wire EDMing, and released the EDAC1 micro EDM ram machine. Makino is also the only manufacturer of a horizontal wire EDM, the UPJ-2. In 2007, Makino introduced SurfaceWIZARD wire EDM technology, designed to eliminate witness lines in stepped parts. Makino created ADVANTiGE™ Technology for the machining of titanium in 2010, which was recognized as a winner of Aviation Week's 2012 Innovation Challenge. \nIn 2018, Makino introduced ATHENA, Makino's voice-activated technology, which is designed for machine tool users. It is intended to make humans more effective at translating, assimilating and analyzing the onslaught of big data.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "15652574", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=15652574", "title": "Phototool", "text": "A phototool is a printed film used in the process of manufacturing a printed circuit board (PCB). The phototool is used as a mask to expose a photoresist material. The main alternative to using phototools is maskless lithography, more commonly referred to as direct imaging.\nTraditionally, phototools were made with silver halide film or diazo film, but in recent years, many suppliers have come out with films that do not fit into either of these categories. All dry-film phototools are printed using a similar process to film photograph. \nThe steps for using a phototool are as follows:", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "15656625", "revid": "248739", "url": "https://en.wikipedia.org/wiki?curid=15656625", "title": "Hot stamping", "text": "Hot stamping or foil stamping is a printing method of relief printing in which pre-dried ink or foils are transferred to a surface at high temperatures. The method has diversified since its rise to prominence in the 19th century to include a variety of processes. After the 1970s, hot stamping became one of the most important methods of decoration on the surface of plastic products.\nProcess.\nIn a hot stamping machine, a die is mounted and heated, with the product to be stamped placed beneath it. A metallized or painted roll-leaf carrier is inserted between the two, and the die presses down through it. The dry paint or foil used is impressed into the surface of the product. The dye-stamping process itself is non-polluting because the materials involved are dry. Pressure and heat cause the relevant sections of the foil to become detached from the carrier material and become bonded with the printing surface.\nTools.\nAlong with foil stamping machines, among the commonly used tools in hot stamping are dies and foil. Dies may be made of metal or silicone rubber, and they may be shaped directly or cast. They can carry high levels of detail to be transferred to the surface and may be shaped to accommodate irregularities in the surface.\nFoils are multilayered coatings that transfer to the surface of the product. Non-metallic foils consist of an adherence base, a color layer, and a release layer. Metallic foils replace the color layer with a layer of chrome or vacuum-metallized aluminum. Metallic foil construction has a metal-like sheen and is available in different metal shades such as gold, silver, bronze, and copper. Pigment foil does not have a metallic sheen but may be glossy or matte. Holographic foil paper includes a 3-dimensional image to provide a distinctive appearance to specific areas of a digitally printed application. Printing is often done on leather or paper.\nDifferent hot stamping machines serve different purposes, but the most common hot stamping machines are simple up-and-down presses. Three of the most common brands are Kwikprint, Kingsley, and Howard. However, for more industrial applications Kluge and Heidelberg presses are more commonly used.\nHistory.\nIn the 19th century, hot stamping became a popular method of applying gold tooling or embossing in book printing on leather and paper. The first patent for hot stamping was recorded in Germany by Ernst Oeser in 1892.\nFrom the 1950s onward, the method became a popular means of marking plastic . Hot Stamping technology for plastic is used for electric components (TV frames, audio components, refrigerators etc.), cosmetic containers (lipstick, cream, mascara, shampoo bottle etc.), automobile parts (interior and exterior materials).\nAs of 1998, it was one of the most commonly used methods of security printing.\nFoil stamping can be used to make Radio-frequency identification (RFID) tags, although screen printing is faster and cheaper.", "Engineering,_Manufacturing": 0.998973608, "qwen": "Yes"}
{"id": "36604500", "revid": "37102400", "url": "https://en.wikipedia.org/wiki?curid=36604500", "title": "Vacuum filler", "text": "A vacuum filler is a machine used for filling pasty products. The pasty products are moved with the aid of a vane cell feed system under a vacuum.\nObjective.\nLevelling the weight of pre-packaged goods in the food sector, especially those involving viscous or pasty products, places extremely high demands on the reproducible accuracy of filling and portioning systems. In order to achieve this, technical and technological issues as well as product-specific characteristics have to be taken into account. In addition to the aforementioned factors, the requirements on the quality of an end product is a key issue when selecting or implementing a technical process solution. The development of vacuum filling machines has made it possible to fulfill both the technical and the quality-related requirements.\nIn the food sector, moving or transporting fluids is achieved with the aid of pump technology. Colloquially, this is known as filling or portioning. Various different types of pumps are used, depending on the type of filling products to be moved. Vacuum fillers with vane cell feed systems and vacuum feeding are commonly used for viscous products. The products are transported with the aid of a hopper with a feeding device, a vane cell feed system under a vacuum and appropriate volume expulsion in the pump housing. This is basically a volumetric feed principle, which means that a certain weight is defined via a volume. In addition to the vane cell feed systems, also known as rotary vane pumps, there are also screw feed systems with feed augers, toothed wheel feed systems and evacuated lifting cylinders. With all these systems, transportation is achieved via volume expulsion under a vacuum.\nVacuum fillers are traditionally used in the meat processing industry as well as in other food sectors. They can also be found in some non-food sectors. Generally speaking, vacuum fillers can be used for filling pasty and compressible products.\nHistory.\nThe first vacuum filler was developed in the early 1960s. The technology has been refined since then.\nRequirements/effects.\nThe pumpability of viscous or pasty products has a key effect on the reliable function of a vacuum filler. Filling products in the food sector can be characterised with the aid of various different properties related to their pumpability (“fillability”). They are either physical characteristics that can be measured directly or they are sensory attributes.\nMode of operation.\nThe key element of a vacuum filler is the vacuum filling principle. The filling product is fed into the feed system mechanically via a hopper with actively driven feeding auger, as well as via vertical “vacuum suction”. Pre-evacuated cells of a vane cell feed system move underneath the hopper. The pressure difference relative to the ambient pressure (underpressure) caused by the evacuation ensures that the cells are filled with product. The feed system moves continuously, thus generating a continuous filling flow. The product is portioned by means of cyclic movements of the feed system. Each cell of the feed system has a particular volume. The portion is defined by the rotation distance of the rotor. The portioning volume is therefore set in the control system by multiplying the rotor's rotation distance by the number of the feed system cells within it. The portion weight must be determined in the control system via the portion volume parameter with the aid of scales.\nStructure and technical requirements.\nVacuum fillers are primarily used in the food trade and in the food industry. Special criteria apply to the design of machines in the food sector due to specific hygiene standards and hygiene regulations. This includes, for example, ensuring that they are easy to dismantle, have level surfaces and seals that can be rinsed from the rear, no dead spaces, ergonomic shapes, a small range of parts and detectable materials/materials suitable for food use. Relatively aggressive ambient conditions, such as reactive detergents, reactive or abrasive filling media, intensive high-pressure cleaning and extreme ambient temperatures, are also faced.\nVacuum fillers are therefore made of a high proportion of stainless steel with a very robust design. Moving parts can be easily dismantled and can be cleaned individually.\nIn addition to the mechanical or design-related issues, complex electronic components in a vacuum filler also have to be taken into account.\nVane cell feed system with hopper.\nThe vane cell feed system mainly consists of a rigid pump housing with attached side plate that is fixed to the pivoting hopper, and a removable rotor with pump vanes and cam. Depending on the machine size there are various different sizes of vane cell feed systems with parts with appropriate dimensions. The hopper can be swivelled to clean and dismantle surfaces and parts that come into contact with filling product. The driven rotor with an appropriate number of slots is located in the pump housing, in which pump vanes form cells with defined volumes when the machine is closed, supported by the cam. Induced by the rotor movement when the machine is started, the cells move in the direction of the vane cell feed system outlet and therefore ensure that a defined product flow is achieved. The weight accuracy of a feed system is partially dependent upon the production precision of the parts and their degree of wear.\nVacuum system.\nThe cells are filled by evacuating the vane cell feed system. By applying a vacuum via a vacuum pump, the filling products are gently drawn out of the hopper into the feed system as soon as an evacuated cell moves underneath the hopper. The vacuum pump is protected by an integrated water separator. The level of vacuum can be set according to the filling product.\nIn addition to the feed effect, the filling product is simultaneously evacuated to a certain extent (approx. 2–4 %). This means that the air content of the filling product decreases and the filling product becomes denser.\nFeeding.\nThe term feeding in the context of vacuum fillers refers to actively moving the filling media in the direction of the lower part of the hopper to support the vacuum approach within the hopper. Feeding is achieved by using moveable feeding augers with scrapers/rigid counter arms. The feeding auger is driven in synchronisation with the rotation of the rotors. Due to the special geometry of both augers and the parallel rotation movement, the filling product is moved vertically in the direction of the vane cell feed system. The required feed intensity depends on the viscosity of the media to be filled. Less active feed is needed with low-viscosity media than with high-viscosity product. There are therefore a variety of combinations or versions of the parts involved in the feeding process.\nMachine base.\nThe machine base acts as the stand for a vacuum filler. For hygiene reasons, bases are made completely of stainless steel. The compact machine base is designed to ensure that it can be moved easily using lifting equipment.\nLifting device.\nLifting devices allow the hopper to be loaded using standard trolleys. They can either be fixed onto the vacuum filler or a mast type lifting device can be positioned separately next to the vacuum filler. Lifting devices can be driven hydraulically or electrically.\nControl and drive systems.\nA computer-aided control system is required for operating the various functions associated with a vacuum filler. Usually, several drives are integrated into the vacuum fillers for the various different applications. With the most modern generations of vacuum fillers, the drives are implemented by means of servo motors and appropriate bus systems.\nSealing devices.\nTo produce individual portions from homogeneous product via a feed system, a “sealing device” is always required at the feed system outlet. This device separates portions and is controlled in synchronisation with the portion output. These devices could be linking devices for sausages, clippers for portionable sausages, dosing valves for tubs and cans, cutting devices for dough as well as forming equipment for dumplings.\nOther feed system principles.\nGenerally speaking, vacuum fillers can be equipped with various different feed systems. However, in principle, the basic machine structure, with a hopper, vacuum system, feeding device, machine base, lifting device, control system and sealing device, is very similar. Depending on the application, each type of feed system has advantages and disadvantages.\nProblems and their solutions.\nMany problems may occur when filling viscous media. The problems are often product-specific and are revealed when the product to be filled takes on an a-typical appearance. Examples of this are an inhomogeneous product appearance with sausage goods or when inserts are ground too finely during the pumping process.\nHowever commercial or legal problems can also arise, in the form of weight deviations or non-compliance with the specified quality regulations (e.g. the guidelines for meat products).\nThese problems are caused by a variety of influences, such as air content or viscosity being too high, insufficient feed volume in the feed system, temperature-related influences and mechanical influences such as friction and fragmentation.\nThe aforementioned problems can be eradicated by modifying upstream process steps, adapting recipes and making technical modifications.\nAuxiliary devices.\nHanging lines in the field of sausage production are auxiliary devices for linking and hanging portions of sausage. In principle, the application is similar to that of a holding device, however significantly higher filling capacities can be achieved. Hanging lines are available with various different degrees of automation.\nWeight control and process documentation.\nMulti-machine electronic control and documentation systems are used to document a filling process involving vacuum fillers or to monitor filling weights.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "17604140", "revid": "713860", "url": "https://en.wikipedia.org/wiki?curid=17604140", "title": "Flange nut", "text": "A flange nut is a nut that has a wide flange at one end that acts as an integrated washer. This serves to distribute the pressure of the nut over the part being secured, reducing the chance of damage to the part and making it less likely to loosen as a result of an uneven fastening surface. These nuts are mostly hexagonal in shape and are made up of hardened steel and often coated with zinc.\nFlange nuts (and bolts) are widely used in automobiles and electronic products.\nVariants.\nSerrated flange nut.\nThe flange may be serrated to provide a locking action. On a serrated flange nut, the serrations are angled such that they keep the nut from rotating in the direction that would loosen the nut. Because of the serrations they cannot be used with a washer or on surfaces that must not be scratched. The serrations help in preventing the vibration of the nut from moving the fastener, thus maintaining the holding power of the nut.\nSelf-aligning nut.\nA self-aligning nut, also known as a spherical nut or leveling nut, is a type of nut used in applications where the fastener is not perpendicular to the surface to which the nut anchors. A flange nut is used inside a specially shaped dished-out washer. The device is commonly used in the aerospace industry. If this nut were not used the object would have to be spot faced so as to provide a surface perpendicular to the fastener.\nStandards.\nThe following specifications define flange nuts:", "Engineering,_Manufacturing": 0.9999892712, "qwen": "Yes"}
{"id": "17604272", "revid": "40051386", "url": "https://en.wikipedia.org/wiki?curid=17604272", "title": "Cerrosafe", "text": "Cerrosafe is a fusible alloy with a low melting point. It is a non-eutectic mixture consisting of 42.5% bismuth, 37.7% lead, 11.3% tin, and 8.5% cadmium that melts between and . It is useful for making reference castings whose dimensions can be correlated to those of the mold or other template due to its well-known thermal expansion properties during cooling. The alloy contracts during the first 30 minutes, allowing easy removal from a mold, then expands during the next 30 minutes to return to the exact original size. It then continues expanding at a known rate for 200 hours, allowing conversion of measurements of the casting back to those of the mold.", "Engineering,_Manufacturing": 0.9999802113, "qwen": "Yes"}
{"id": "17604870", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=17604870", "title": "Well nut", "text": "A well nut is a blind rivet-like type of fastener used to blindly fasten a piece (much like a molly bolt) and to seal the bolt hole.\nThey are often referred to by the proprietary name Rawlnut or Rawl nut, the name by which they are known in the UK.\nDescription.\nA well nut consists of a flanged neoprene bushing with a nut embedded in the non-flanged end. The bolt is passed through one of the pieces to be fastened and threaded onto the nut from the flanged end. The non-flanged end is then inserted through the other piece to be fastened. As the bolt is tightened, friction from the neoprene flange against the piece being fastened prevents the nut from turning. The bushing is compressed by the nut, forming a lip behind the piece being fastened, which compresses the fastened piece and seals the bolt hole. It can also be used in a solid workpiece. As the bolt draws the embedded nut towards it, the walls of the well exert a force on the hole walls, anchoring it.\nWell nuts are not particularly strong, but are useful for sealing holes and/or isolating vibrations.\nHistory.\nThe well nut was originally developed by the United Shoe Machinery Corporation (USMC).", "Engineering,_Manufacturing": 0.9999991655, "qwen": "Yes"}
{"id": "17605567", "revid": "948899267", "url": "https://en.wikipedia.org/wiki?curid=17605567", "title": "Distorted thread locknut", "text": "A distorted thread locknut, is a type of locknut that uses a deformed section of thread to keep the nut from loosening from vibrations or rotation of the clamped item. They are broken down into four types: elliptical offset nuts, centerlock nuts, toplock nuts and partially depitched (Philidas) nuts.\nHigh temperature use.\nBecause these nuts are solid metal, they are effective in elevated temperature settings, unlike nyloc nuts. High grade nuts can withstand temperatures up to .\nSafety factors.\nHigh strength distorted thread nuts cannot be used with low strength fasteners because the hard nut will act like a die and destroy the threads on the fastener.\nElliptical offset nuts.\nElliptical offset nuts is a catch-all category that encompasses designs known as oval locknuts or non-slotted hex locknuts. The salient feature is that the thread form has been deformed at one end so that the threads are no longer perfectly circular. The deformed end is usually shaped into an ellipse or obround triangle. These are known as one-way nuts as the nut may be easily started on the male fastener from the bottom non-deformed portion, but are practically impossible to start from the deformed end. As the male fastener reaches the deformed section it stretches the threads of the nut elastically back into a circle. This action increases the friction between the nut and the fastener greatly and creates the locking action. Due to the elastic nature of the deformation the nuts can be reused indefinitely.\nCenterlock nuts.\nCenter lock nuts are similar to elliptical offset nuts, except that they are distorted in the middle of the nut. This allows the nut to be started from either side.\nToplock nuts.\nToplock nuts are also similar to elliptical offset nuts, except that the whole thread on one end is not distorted. Instead only three small sections of the thread are deformed on one end.\nPartially depitched nuts.\nPartially depitched nuts are commonly called Philidas nuts, after their originator and current manufacturer, and differ from the above three nut types insofar as a portion of the thread is displaced axially, this being facilitated by one or more slots perpendicular to the axis.", "Engineering,_Manufacturing": 0.9975194931, "qwen": "Yes"}
{"id": "17609546", "revid": "9991578", "url": "https://en.wikipedia.org/wiki?curid=17609546", "title": "T-slot nut", "text": "A T-slot nut is used with a threaded clamp to position and secure pieces being worked on in a workshop. The T-slot nut slides along a T-slot track, which is set in workbench or table for a router, drill press, or bandsaw. T-slot nuts are also used with T-slot structural framing to build a variety of industrial structures and machines.\nA T-slot bolt is generally stronger than a T-slot nut and hex-head cap screw.\nA heavy-duty T-slot nut with a M12 bolt is rated to support 10000 N (about 1 imperial ton at rest). \n and the T-slot nuts to fit into them comprised the first modular system developed for use in mechanical engineering in 1980 by item Industrietechnik. The item aluminum framing system has since been expanded to include a variety of t-slot nuts that have been designed for specific applications. \nThe item system is very similar to the \"channel-and-groove design\" used in some toys.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "17610065", "revid": "37319028", "url": "https://en.wikipedia.org/wiki?curid=17610065", "title": "Speed nut", "text": "A speed nut, aka sheet metal nut or Tinnerman nut, is a type of locknut with two sheet metal prongs that act as one thread. They are made from spring steel. \nThe fastener serves the functions of both a lock washer and a nut. As the fastener is tightened in the nut the prongs are drawn inward until they exert pressure on the root of the thread on the fastener. When the fastener is tightened, the base of the nut, which is arched, elastically deforms and applies a force to the fastener, which locks it from loosening under vibrations.\nThere are many different types of speed nuts, mostly dependent on the shape of the nut, how it attaches to the workpiece, and what type of screw can be used. Most types are designed for either machine screws or sheet metal screws. Some nuts do not attach to the workpiece. These are usually shaped as either a rectangle, a flange nut, or a hex nut; the rectangular speed nut is also known as a flat-style speed nut. Speed nuts that attach to the workpiece usually are some form of a J-nut or U-nut.\nHistory.\nThe speed nut was invented in 1923 and patented in 1924 https://patents.google.com/patent/US1512653A/en?assignee=albert+tinnerman&oq=albert+tinnerman&sort=old by Albert H. Tinnerman, son of George Tinnerman, who founded Tinnerman Steel Range Company. The company, established in 1870, originally manufactured sheet metal kitchen ranges. However, after Tinnerman invented the nut to resolve issues with stove shipping, the invention became so successful it led the company away from building stoves to building fasteners.\nTinnerman Products was formed in 1939, and evolved from the Speed Nut development with manufacturing plants in Cleveland, Ohio. A manufacturing plant was constructed on Brookpark Road in the early 1950s. Tinnerman Products later merged with Eaton Yale & Towne in 1969. In 1999, Eaton sold Tinnerman to TransTechnology for $173 million. In 2009, ARaymond purchased Tinnerman for an undisclosed sum.", "Engineering,_Manufacturing": 0.999746263, "qwen": "Yes"}
{"id": "17617913", "revid": "39151475", "url": "https://en.wikipedia.org/wiki?curid=17617913", "title": "Customer demand planning", "text": "Customer demand planning (CDP) is a business-planning process that enables sales teams to develop demand forecasts as input to service-planning processes, production, inventory planning and revenue planning.\nDefinition.\nCDP is an aspect of managing value chains. Generally, the first step of CDP is to forecast product demand. A manager can plan resource deployment in accordance with the resulting forecasts. It's a bottom-up approach vs. top down planning. Associated risks with this method are: Low forecast accuracy and numbers of planners required. There are various software systems that are designed to forecast demand and plan operations. To test the added value of implementing bottom-up approach, applications are providing simulations functionalities to estimate the resulting demand forecast accuracy (e.g. POS sales ; sales invoices ; shipments, etc.)\nIn the manufacturer to retailer model, customer collaborative partnerships have become more common since the 1990s. Although there was industry support behind CPFR (Collaborative Planning, Forecasting and Replenishment), manufacturers and retailers are adopting different versions of collaborative forecasting and replenishment strategies. These include collaborative-VMI, CPFR, account based forecasting, CMI, shared single forecast and replenishment etc.\nDiscovering markets.\nThe challenges and complexities faced by the retailer are somewhat different from the challenges faced by suppliers (manufacturers and distributors). The demand management technology for the merchant is somewhat different from that of the brand or manufacturer on the supply-side.\nCustomer demand planning aims at matching customer supply planning logic and imply CPFR type collaboration.\nAreas components of demand management include customer experience, demand creation, inventory and pricing optimization, channel management, sourcing, transportation optimization and advanced practices in technology.", "Engineering,_Manufacturing": 0.9999771118, "qwen": "Yes"}
{"id": "64749777", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=64749777", "title": "Jetting (injection moulding defect)", "text": "Jetting is an moulding defect that can occur in the manufacturing process of injection moulding. Jetting is a snake-like stream which occurs when polymer melt is pushed at a high velocity through restrictive areas.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "64758384", "revid": "43558034", "url": "https://en.wikipedia.org/wiki?curid=64758384", "title": "Adaptive machine", "text": "The adaptive machine is a category of flexible industrial machinery characterized by the ability to intelligently adapt itself to the product to be produced, e.g. to move individual products through the manufacturing, assembly, inspection, packaging and other process stations required for to produce them.\nDesign approach.\nAt first glance, the adaptive capabilities are rooted in software. But a second look reveals that machines handle physical products. For doing so machines need a proper mechanical design as well as a proper electrical design to power the mechanical movements. An adaptive machine is best designed by applying an interdisciplinary mechatronic design approach where mechanics, electrics and software as well as their interfaces and interactions are considered holistically.  \nPurpose.\nThe primary function of an adaptive machine is to make production more flexible by enable greater product variety (e.g. with respect to product size and shape) and smaller batches. The ultimate goal of an adaptive machine is mass customization, and the holy grail of economical batch size, one product, made to customer order rather than for stock. As far back as 1997, the \"Harvard Business Review\" identified four approaches to mass customization, one being ‘adaptive customizers’ in which standard products are adapted by the customer. The adaptive machine is actually more representative of \"HBR’s\" collaborative and cosmetic approaches, in which products and/or packaging are customized during production.\nThis description was provided by the Frost & Sullivan research firm in October 2017.\nCore enabling technologies.\nThe concept of the adaptive machine relies on the following core technologies to enable adaptability and to achieve high levels of flexibility.  \nTerminology and history.\nThe term has been attributed to B&R Industrial Automation, where it is used in their product descriptions, white papers and use cases. In the packaging sector the evolution of machine technology has been roughly categorized by OMAC as follows:\nGen 4 will be the generation of the adaptive machine.\nThe adaptive machine terminology was developed to define a category, as well as to define the purpose, functionality and especially the application benefits of such technologies to make production processes more flexible and productive in terms of commercial objectives.\nThe adaptive machine and machine learning.\nThe adaptive machine category should not be confused with adaptive manufacturing or adaptive machine learning. Adaptive machines can be quite effective in an adaptive manufacturing environment and can benefit from adaptive machine learning applications. But they are neither interchangeable terms nor require one another to fulfill their basic definitions.\nAdaptive machines in the commercial marketplace.\nAdaptive machines are increasingly entering the industrial workplace. Applications include ‘bottling on demand,’ in which soft drinks are individually blended at the filling valve and fitted with customized closures and labels and product codes.\nAnother is a labeling machine that can handle different size and shape bottles and labels without stopping and performing a changeover.\nAnother example is a bottle unscrambler that uses a combination of delta robots and the synchronized motion of two shuttles to act as infinitely adjustable pucks, to handle different container shapes and sizes, also without changeover.\nA cartoning machine uses a track system in place of a variable pitch bucket conveyor for collating and loading different primary packs into cartons.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "64760108", "revid": "1170380256", "url": "https://en.wikipedia.org/wiki?curid=64760108", "title": "Track technology", "text": "Depending on the supplier, track technology has been variously termed a smart conveyance system, intelligent track system, industrial transport system, independent cart technology, smart carriage technology, linear or extended or flexible transport system, or simply a conveyor or conveyance platform. They are also referred to as linear motors or long stator linear motors, reflecting the underlying technology of the track (stator) and shuttles (platen, equivalent to the rotor in a conventional rotary electric motor).  Shuttles have also been called carriers, movers, platforms and pallets.\nList of commercially available track systems.\nThe following is a list of commercially available track systems by product name:\nAreas of application.\nTrack technology is – among other technologies like machine vision and robotics – one of the key enablers for the adaptive machine.\nThe concept of the adaptive machine also goes beyond track technology to achieve their high levels of flexibility.  One complementary technology is the industrial robot, which by definition possesses the same programmable flexibility.  Of particular interest is the ability of both robots and track systems to operate safely along with humans in a collaborative environment. This recent development allows for a combination of manual and automated assembly tasks, maintenance and materials replenishment without stopping production.\nMachine vision can play a pivotal role when integrated into an adaptive machine. Vision can identify individual shuttles and their contents in order to guide them to the appropriate workstations. Vision has long been used to automate robot guidance, inspection, orientation and related tasks.\nGiven the adaptive machine's flexibility to respond to consumer demand generation, Internet of Things and e-commerce technologies are complementary, providing the connection between internal production resources and commercial systems in a manufacturer's digital business model.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "19426401", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=19426401", "title": "Mitsubishi Caterpillar Forklifts", "text": "Mitsubishi Caterpillar Forklifts, Inc. is a group of multinational companies that were formed under a joint venture between Mitsubishi Heavy Industries (MHI) and Caterpillar Inc. in order to manufacture and market trucks. The group manufactures and distributes Cat Lift Trucks, Mitsubishi Forklift Trucks and Jungheinrich warehouse products to the material handling industry.\nHistory.\nThe joint venture was formed on July 1, 1992 when MHI entered a joint venture with Caterpillar Inc.\nThe joint venture includes the following companies based on the geographic markets they serve:\nThe joint venture combined a variety of operational strengths to form a successful company. Mitsubishi's operational strengths include cost-effective manufacturing expertise, vast engineering resources and possession proprietary powertrain. Caterpillar Inc. provided marketing experience, worldwide dealer organization, brand recognition and effective product support.\nMitsubishi Caterpillar Forklift America.\nMitsubishi Caterpillar Forklift America Inc. (\"MCFA\"), headquartered in Houston, Texas is a manufacturer and distributor of material handling equipment and parts under the Mitsubishi Forklift Trucks, Cat Lift Trucks, and Jungheinrich brand names. MCFA also owns the rights to Towmotor brand name, and manufactures under it. MCFA is ISO 9001-2000 certified and has obtained compliance certification from the California Air Resources Board (CARB). MCFA provides a full line of forklifts with complete sales and product support through more than 400 dealer locations throughout the United States, Canada and Latin America.\nThe company's . facility in Houston is located on of land and employs 1,200 workers, capable of producing over 25,000 forklifts per annum.\nMCFA is a subsidiary of Mitsubishi Heavy Industries and one of the worldwide MCF group of companies:\nEach group, with the exception of MLAP, is responsible for design engineering, manufacturing and marketing the product lines and handling parts distribution in their respective regions.\nHistory.\nMCFA was formed through a joint venture in 1992 between two major companies, Mitsubishi Heavy Industries, Ltd. (MHI) and Caterpillar Industrial Inc. (CII). Jungheinrich Forklifts joined this partnership on January 1, 2010 through a manufacturing and distribution agreement with MCFA.\nMitsubishi Caterpillar Forklift Europe.\nMitsubishi Caterpillar Forklift Europe B.V. (MCFE) is a manufacturer and distributor of materials handling products under the brand names Mitsubishi Forklift Trucks and Cat Lift Trucks.\nServing customers in Europe (including Russia and the Commonwealth of Independent States – CIS), Africa and the Middle East, it is a subsidiary of Mitsubishi Heavy Industries Ltd (MHI) and Caterpillar Inc. whose other materials handling subsidiaries include:\nMCFE is based in Almere, the Netherlands, from which it supports a network of more than a hundred independently owned and operated dealers and distributors covering more than 72 countries.\nMCFE has received the following quality accreditations from the International Organization for Standardization: ISO 9001, ISO 9002, ISO 14001\nHistory.\nMCFE was formed in 1992 when MHI entered a joint venture with Caterpillar Inc.\nProduction and support facilities.\nMCFE’s headquarters are located at the ‘De Vaart’ industrial park in Almere, the Netherlands. They also own a separate manufacturing facility in Järvenpää, Finland, and can call on the resources of the Mitsubishi Caterpillar Forklift centres in Asia and America for further manufacturing capacity.\nIn addition, MCFE has a central European parts centre based in Puurs, Belgium. The European parts operation is supplemented and supported by those in Asia and America. \nIn 2012 production in Almere stopped due to recession and lack of sales. MCFE changed from a production facility to a sales office.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "19455326", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=19455326", "title": "Machining vibrations", "text": "In machining, vibrations, also called chatter, are the relative movements between the workpiece and the cutting tool. The vibrations result in waves on the machined surface. This affects typical machining processes, such as turning, milling and drilling, and atypical machining processes, such as grinding.\nA chatter mark is an irregular surface flaw left by a wheel that is \"out of true\" (off-center) in grinding, or regular marks left when turning a long piece on a lathe, due to machining vibrations.\nAs early as 1907, Frederick W. Taylor described machining vibrations as the most obscure and delicate of all the problems facing the machinist, an observation still true today, as shown in many publications on machining.\nThe explanation of the machine tool regenerative chatter was made by Tobias. S. A. and W. Fishwick in 1958, by modeling the feedback loop between the metal cutting process and the machine tool structure, and came with the stability lobes diagram. The structure stiffness, damping ratio and the machining process damping factor, are the main parameters that defines the limit where the machining process vibration is prone to enlarge with time. \nMathematical models make it possible to simulate machining vibration quite accurately, but in practice it is always difficult to avoid vibrations.\nAvoidance techniques.\nBasic rules for the machinist for avoiding vibrations:\nIndustrial context.\nThe use of high speed machining (HSM) has enabled an increase in productivity and the realization of workpieces that were impossible before, such as thin walled parts. Unfortunately, machine centers are less rigid because of the very high dynamic movements. In many applications, i.e. long tools, thin workpieces, the appearance of vibrations is the most limiting factor and compels the machinist to reduce cutting speeds and feeds well below the capacities of machines or tools.\nVibration problems generally result in noise, bad surface quality and sometimes tool breakage. The main sources are of two types: forced vibrations and self-generated vibrations.\nForced vibrations are mainly generated by interrupted cutting (inherent to milling), runout, or vibrations from outside the machine.\nSelf generated vibrations are related to the fact that the actual chip thickness depends also on the relative position between tool and workpiece during the previous tooth passage. Thus increasing vibrations may appear up to levels which can seriously degrade the machined surface quality.\nLaboratory research.\nIndustrial and academic researchers have widely studied machining vibration. Specific strategies have been developed, especially for thin-walled work pieces, by alternating small machining passes in order to avoid static and dynamic flexion of the walls. The length of the cutting edge in contact with the workpiece is also often reduced in order to limit self-generated vibrations.\nThe modeling of the cutting forces and vibrations, although not totally accurate, makes it possible to simulate problematic machining and reduce unwanted effects of vibration.\nMultiplication of the models based on stability lobe theory, which makes it possible to find the best spindle speed for machining, gives robust models for any kind of machining.\nTime domain simulations compute workpiece and tool position on very small time scales without great sacrifice in accuracy of the instability process and of the surface modeled. These models need more computing resources than stability lobe models, but give greater freedom (cutting laws, runout, ploughing, finite element models). Time domain simulations are quite difficult to robustify, but a lot of work is being done in this direction in the research laboratories.\nIn addition to stability lobe theory, the use of variable tool pitch often gives good results, at a relatively low cost. These tools are increasingly proposed by tool manufacturers, although this is not really compatible with a reduction in the number of tools used. Other research leads are also promising, but often need major modifications to be practical in machining centers.\nTwo kinds of software are very promising: Time domain simulations which give not yet reliable prediction but should progress, and vibration machining expert software, pragmatically based on knowledge and rules.\nIndustrial methods used to limit machining vibrations.\nThe usual method for setting up a machining process is still mainly based on historical technical knowhow and on trial and error method to determine the best parameters. According to the particular skills of a company, various parameters are studied in priority, such as depth of cut, tool path, workpiece set-up, and geometrical definition of the tool. When a vibration problem occurs, information is usually sought from the tool manufacturer or the CAM (Computer-aided manufacturing) software retailer, and they may give a better strategy for machining the workpiece. Sometimes, when vibration problems are too much of a financial prejudice, experts can be called upon to prescribe, after measurement and calculation, spindle speeds or tool modifications.\nCompared to the industrial stakes, commercial solutions are rare. To analyse the problems and to propose solutions, only few experts propose their services. Computational software for stability lobes and measurement devices are proposed but, in spite of widespread publicity, they remain relatively rarely used. Lastly, vibration sensors are often integrated into machining centers but they are used mainly for wear diagnosis of the tools or the spindle.\nNew Generation Tool Holders and especially the Hydraulic Expansion Tool Holders minimise the undesirable effects of vibration to a large extent. First of all, the precise control of total indicator reading to less than 3 micrometres helps reduce vibrations due to balanced load on cutting edges and the little vibration created thereon is absorbed largely by the oil inside the chambers of the Hydraulic Expansion Tool Holder.\nThe machining vibration is often coming from the tool holder having a high L/D ratio and low stiffness. Stiffening the tool holder with tungsten carbide material is widely used when the tool diameter/weight is small, and the material cost of tungsten carbide is not high. A longer reach at L/D above 4 until 14, a mass damper is necessary to effectively damp out the vibration with a counteracting force to the tool structure. The simple form of mass damper has a heavy weight (made of tungsten or lead) supported by rubber rings, with or without a tuning mechanism. The tuning mechanism enables the mass damper to cover a wider L/D ratio (associated with vibration frequency) range. A more advanced mass damper on cutting tools use viscous fluid or damping oil to improve the dampening efficiency at the targeted L/D ratio (vibration frequency). The latest mass damper on cutting tools are making use of special polymers that has frequency dependent stiffness, and use these polymers to make both self-tuning/adjusting to cover a wider L/D ratio.\nThe machine tools with sensors integrated, which can measure the vibration in machining and provide a feedback to automatically tune the mass damper, is already demonstrated in lab-scale. The deployment of such solutions is still pending on its ease of use and cost.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "18131806", "revid": "4055378", "url": "https://en.wikipedia.org/wiki?curid=18131806", "title": "Cryogenic deflashing", "text": "Cryogenic deflashing is a deflashing process that uses cryogenic temperatures to aid in the removal of flash on cast or molded workpieces. These temperatures cause the flash to become stiff or brittle and to break away cleanly. Cryogenic deflashing is the preferred process when removing excess material from oddly shaped, custom molded products.\nProcess.\nParts are loaded into a parts basket. A cryogen, such as liquid nitrogen, is used to cool the workpieces; once cooled they are tumbled and blasted with media pellets, ranging size from . In some instances, cryogenic deflashing does not utilize a blasting action, relying instead only on the tumbling of the parts to remove flash on the outer edges.\nAdvantages.\nCryogenic deflashing provides various advantages over manual deflashing and other traditional deflashing methods.\nApplications.\nA wide range of molded materials can utilize cryogenic deflashing with proven results. These include:\nExamples of applications that use cryogenic deflashing include:\nToday, many molding operations are using cryogenic deflashing instead of rebuilding or repairing molds on products that are approaching their end-of-life. It is often more prudent and economical to add a few cents of production cost for a part than invest in a new molding tool that can cost hundreds of thousands of dollars and has a limited service life due to declining production forecasts.\nIn other cases, cryogenic deflashing has proven to be an enabling technology, permitting the economical manufacture of high quality, high precision parts fabricated with cutting edge materials and compounds.", "Engineering,_Manufacturing": 0.9999482632, "qwen": "Yes"}
{"id": "3676886", "revid": "1133132248", "url": "https://en.wikipedia.org/wiki?curid=3676886", "title": "Linear-motion bearing", "text": "A linear-motion bearing or linear slide is a bearing designed to provide free motion in one direction. There are many different types of linear motion bearings.\nMotorized linear slides such as machine slides, X-Y tables, roller tables and some dovetail slides are bearings moved by drive mechanisms. Not all linear slides are motorized, and non-motorized dovetail slides, ball bearing slides and roller slides provide low-friction linear movement for equipment powered by inertia or by hand. All linear slides provide linear motion based on bearings, whether they are ball bearings, dovetail bearings, linear roller bearings, magnetic or fluid bearings. X-Y tables, linear stages, machine slides and other advanced slides use linear motion bearings to provide movement along both X and Y multiple axis.\nRolling-element bearing.\nA rolling-element bearing is generally composed of a sleeve-like outer ring and several rows of balls retained by cages. The cages were originally machined from solid metal and were quickly replaced by stampings. It features smooth motion, low friction, high rigidity and long life. They are economical, and easy to maintain and replace. Thomson Industries (currently owned by Altra Industrial Motion) is generally given credit for first producing [what is now known as] a linear ball bearing.\nRolling-element bearings are manufactured in two forms: ball bearing slides and roller slides.\nBall bearing slides.\nAlso called \"ball slides,\" ball bearing slides are the most common type of linear slide. Ball bearing slides offer smooth precision motion along a single-axis linear design, aided by ball bearings housed in the linear base, with self-lubrication properties that increase reliability. Ball bearing slide applications include delicate instrumentation, robotic assembly, cabinetry, high-end appliances and clean room environments, which primarily serve the manufacturing industry but also the furniture, electronics and construction industries. For example, a widely used ball bearing slide in the furniture industry is a ball bearing drawer slide.\nCommonly constructed from materials such as aluminum, hardened cold rolled steel and galvanized steel, ball bearing slides consist of two linear rows of ball bearings contained by four rods and located on differing sides of the base, which support the carriage for smooth linear movement along the ball bearings. This low-friction linear movement can be powered by either a drive mechanism, inertia or by hand. Ball bearing slides tend to have a lower load capacity for their size compared to other linear slides because the balls are less resistant to wear and abrasions. In addition, ball bearing slides are limited by the need to fit into housing or drive systems.\nThe travelling distance of linear recirculating ball bearings is only limited by the length of their rail, as the balls recirculate inside the bearing's housing. Linear non-recirculating ball bearings have balls installed on a bracket and only move in one axis without recirculation. Since the balls do not recirculate, this type of bearings can provide extremely smooth motion. However, the travelling distance of linear non-recirculating ball bearings is limited by the length of the bracket.\nRoller slides.\nAlso known as crossed roller slides, roller slides are non-motorized linear slides that provide low-friction linear movement for equipment powered by inertia or by hand. Roller slides are based on linear roller bearings, which are frequently criss-crossed to provide heavier load capabilities and better movement control. Serving industries such as manufacturing, photonics, medical and telecommunications, roller slides are versatile and can be adjusted to meet numerous applications which typically include clean rooms, vacuum environments, material handling and automation machinery.\nRoller slides work similarly to ball bearing slides, except that the bearings housed within the carriage are cylinder-shaped instead of ball shaped. The rollers crisscross each other at a 90° angle and move between the four semi-flat and parallel rods that surround the rollers. The rollers are between \"V\" grooved bearing races, one being on the top carriage and the other on the base. Typically, bearing housings are constructed from aluminum while the rollers are constructed from steel.\nAlthough roller slides are not self-cleaning, they are suitable for environments with low levels of airborne contaminants such as dirt and dust. As one of the more expensive types of linear slides, roller slides are capable of providing linear motion on more than one axis through stackable slides and double carriages. Roller slides offers line contact versus point contact as with ball bearings, creating a broader contact surface due to the consistency of contact between the carriage and the base and resulting in less erosion.\nPlain bearing.\nPlain bearings are very similar in design to rolling-element bearings, except they slide without the use of ball bearings. If they are cylindrical in shape, they are often called bushings. Bushings can be metal or plastic, or even air.\nDovetail slides.\nDovetail slides, or dovetail way slides are typically constructed from cast iron, but can also be constructed from hard-coat aluminum, acetal or stainless steel. Like any bearing, a dovetail slide is composed of a stationary linear base and a moving carriage. a Dovetail carriage has a v-shaped, or dovetail-shaped protruding channel which locks into the linear base's correspondingly shaped groove. Once the dovetail carriage is fitted into its base's channel, the carriage is locked into the channel's linear axis and allows free linear movement. When a platform is attached to the carriage of a dovetail slide, a dovetail table is created, offering extended load carrying capabilities.\nDovetail slides are advantageous when it comes to load capacity, affordability and durability. Capable of long travel, dovetail slides are more resistant to shock than other bearings, and they are mostly immune to chemical, dust and dirt contamination. Dovetail slides can be motorized, mechanical or electromechanical. Electric dovetail slides are driven by a number of different devices, such as ball screws, belts and cables, which are powered by functional motors such as stepper motors, linear motors and handwheels. Dovetail slides are direct contact systems, making them fitting for heavy load applications including CNC machines, shuttle devices, special machines and work holding devices. Mainly used in the manufacturing and laboratory science industries, dovetail slides are ideal for high-precision applications.\nCompound slides.\nSlides can be constructed with two sections or multiple sections. A slide with two sections can only extend approximately 3/4 of the total compressed slide length. A compound slide typically has three sections: fixed, floating intermediate member, and the section attached to the equipment. A compound slide can extend at least as far as the compressed slide length and typically a bit more. In the case of rack slides, this allows the equipment to extend completely out of the rack allowing access for service or connection of cables and such to the back of the equipment.\nRack slides.\nRack slides are specifically intended for mounting equipment into 19-inch racks or 23-inch racks. These can be friction bearing, ball bearing, or roller bearing. They are sized to fit into racks with mounting flanges on the ends to mate to the mounting holes in racks. In some cases, one mounting flange is formed into the rack slide with an adapter bracket attached to the other end to accommodate different depths of the rack. The outer fixed member is attached to the rack and the inner moving member is generally screwed to the side of the mounted equipment. Rack slides are typically compound or 3-part slides allowing full extension of the mounted equipment and generally include provision for sliding the inner member completely free to allow removal of the equipment from the rack. They can also include stops to prevent accidentally pulling the equipment out of the rack without releasing the stop mechanism.\nThere can be proprietary configurations which, for example, may clip to the equipment without the use of screws or can be clipped into an appropriately designed rack. But the basic geometry is the same regardless of how they are mounted.", "Engineering,_Manufacturing": 1.0000052452, "qwen": "Yes"}
{"id": "3682802", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=3682802", "title": "Vespel", "text": "Vespel is the trademark of a range of durable high-performance polyimide-based plastics made by DuPont. The one shown in the structure on the right was the first to be commercialized.\nCharacteristics and applications.\nVespel is mostly used in aerospace, semiconductor, and transportation technology. It combines heat resistance, lubricity, dimensional stability, chemical resistance, and creep resistance, and can be used in hostile and extreme environmental conditions.\nUnlike most plastics, it does not produce significant outgassing even at high temperatures, which makes it useful for lightweight heat shields and crucible support. It also performs well in vacuum applications, down to extremely low cryogenic temperatures. However, Vespel tends to absorb a small amount of water, resulting in longer pump time while placed in a vacuum.\nAlthough there are polymers surpassing polyimide in each of these properties, the combination of them is the main advantage of Vespel.\nThermophysical properties.\nVespel is commonly used as a thermal conductivity reference material for testing thermal insulators, because of high reproducibility and consistency of its thermophysical properties. For example, it can withstand repeated heating up to 300 °C without altering its thermal and mechanical properties. Extensive tables of measured thermal diffusivity, specific heat capacity, and derived density, all as functions of temperature, have been published.\nMagnetic properties.\nVespel is used in high-resolution probes for NMR spectroscopy because its volume magnetic susceptibility (−9.02 ± 0.25×10−6 for Vespel SP-1 at 21.8 °C) is close to that of water at room temperature (−9.03×10−6 at 20 °C ) Negative values indicate that both substances are diamagnetic. Matching volume magnetic susceptibilities of materials surrounding NMR sample to that of the solvent can reduce susceptibility broadening of magnetic resonance lines.\nProcessing for manufacturing applications.\nVespel can be processed by direct forming (DF) and isostatic molding (basic shapes – plates, rods and tubes). For prototype quantities, basic shapes are typically used for cost efficiency since tooling is quite expensive for DF parts. For large scale CNC production, DF parts are often used to reduce per part costs, at the expense of material properties which are inferior to those of isostatically produced basic shapes.\nTypes.\nFor different applications, special formulations are blended/compounded. Shapes are produced by three standard processes: \nDirect-formed parts have lower performance characteristics than parts that have been machined from compression-molded or isostatic shapes. Isostatic shapes have isotropic physical properties, whereas direct formed and compression molded shapes exhibit anisotropic physical properties.\nSome examples of standard polyimide compounds are:", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "3683130", "revid": "42327269", "url": "https://en.wikipedia.org/wiki?curid=3683130", "title": "Machine shop", "text": "A machine shop or engineering workshop is a room, building, or company where machining, a form of subtractive manufacturing, is done. In a machine shop, machinists use machine tools and cutting tools to make parts, usually of metal or plastic (but sometimes of other materials such as glass or wood). A machine shop can be a small business (such as a job shop) or a portion of a factory, whether a toolroom or a production area for manufacturing. The building construction and the layout of the place and equipment vary, and are specific to the shop; for instance, the flooring in one shop may be concrete, or even compacted dirt, and another shop may have asphalt floors. A shop may be air-conditioned or not; but in other shops it may be necessary to maintain a controlled climate. Each shop has its own tools and machinery which differ from other shops in quantity, capability and focus of expertise.\nThe parts produced can be the end product of the factory, to be sold to customers in the machine industry, the car industry, the aircraft industry, or others. It may encompass the frequent machining of customized components. In other cases, companies in those fields have their own machine shops.\nThe production can consist of cutting, shaping, drilling, finishing, and other processes, frequently those related to metalworking. The machine tools typically include metal lathes, milling machines, machining centers, multitasking machines, drill presses, or grinding machines, many controlled with computer numerical control (CNC). Other processes, such as heat treating, electroplating, or painting of the parts before or after machining, are often done in a separate facility.\nA machine shop can contain some raw materials (such as bar stock for machining) and an inventory of finished parts. These items are often stored in a warehouse. The control and traceability of the materials usually depend on the company's management and the industries that are served, standard certification of the establishment, and stewardship.\nA machine shop can be a capital intensive business, because the purchase of equipment can require large investments. A machine shop can also be labour-intensive, especially if it is specialized in repairing machinery on a job production basis, but production machining (both batch production and mass production) is much more automated than it was before the development of CNC, programmable logic control (PLC), microcomputers, and robotics. It no longer requires masses of workers, although the jobs that remain tend to require high talent and skill. Training and experience in a machine shop can both be scarce and valuable.\nMethodology, such as the practice of 5S, the level of compliance over safety practices and the use of personal protective equipment by the personnel, as well as the frequency of maintenance to the machines and how stringent housekeeping is performed in a shop, may vary widely from one shop to another.\nHistory.\nUntil the 19th century.\nThe first machine shops started to appear in the 19th century when the Industrial Revolution was already long underway. Before the industrial revolution parts and tools were produced in workshops in local villages and cities on small-scale often for a local market. The first machinery that made possible the Industrial Revolution were also developed in similar workshops.\nThe production machines in the first factories were built on site, where every part was still individually made to fit. After some time those factories started their own workshops, where parts of the existing machinery were repaired or modified. In those days textiles were the dominant industry, and these industries started to further develop their own machine tools.\n19th century.\nFurther development early in the 19th century in England, Germany and Scotland of machine tools and cheaper methods for the production of steel, such as the Bessemer steel, triggered the Second Industrial Revolution, which culminated in early factory electrification, mass production and the production line. The machine shop emerged as Burghardt called, a \"place in which metal parts are cut to the size required and put together to form mechanical units or machines, the machines so made to be used directly or indirectly in the production of the necessities and luxuries of civilization.\"\nThe rise of machine shops and their specific manufacturing and organizational problems triggered the early job shop management pioneers, whose theories became known as scientific management. One of the earliest publications in this field was Horace Lucian Arnold, who in 1896 wrote a first series of articles about \"Modern Machine-Shop Economics.\" This work stretched out from production technology, production methods and factory lay out to time studies, production planning, and machine shop management. A series of publications on these topics would follow. In 1899 Joshua Rose published the book \"Modern machine-shop practice,\" about the operation, construction, and principles of shop machinery, steam engines, and electrical machinery.\n20th century.\nIn 1903 the \"Cyclopedia of Modern Shop Practice\" was published with Howard Monroe Raymond as Editor-in-Chief, and in the same year Frederick Winslow Taylor published his \"Shop management; a paper read before the American society of mechanical engineers. New York.\" Taylor had started his workmanship as a machine-shop laborer at Midvale Steel Works in 1878, and worked his way up to machine shop foreman, research director, and finally chief engineer of the works. As an independent consulting engineer one of his first major assignments was in 1898 at Bethlehem Steel was to solve an expensive machine-shop capacity problem.\nIn 1906 Oscar E. Perrigo published the popular book \"Modern machine shop,\" construction the equipment and management of machine shops. The first part of \"Modern machine shop,\" Perrigo (1906) focussed on the physical construction of the building and presented a model machine shop. With this model machine shop, Perrigo explored the way the space in factories could be organized. This was not uncommon in his days. Many industrial engineers, like Alexander Hamilton Church, J. Slater Lewis, Hugo Diemer etc., published plans for some new industrial complex.\nThese works among others cumulated in the scientific management movement on which Taylor in 1911 wrote his famous \"The Principles of Scientific Management,\" a seminal text of modern organization and decision theory, with a significant part dedicated to the organization of machine shops. The introduction of new cutting materials as high-speed steel, and better organization of the production by implementing new scientific management methods such as planning boards (see image), significantly improved machine shop productivity and efficiency of machine shops. In the course of the 20th century, these further increased with the further development of technology.\nIn the early 20th century, the power for the machine tools was still supplied by a mechanical belt, which was powered by a central steam engine. In the course of the 20th-century electric motors took over the power supply of the machine tools.\nAs materials and chemical substances, including cutting oil, become more sophisticated, the awareness of the impact on the environment slowly grew. In parallel to the acknowledgment of the ever-present reality of accidents and potential occupational injury, the sorting of scrap materials for recycling and the disposal of refuse evolved in an area related to the environment, safety, and health. In regulated machine shops this would turn into a constant practice supported by what would be a discipline known as EHS (for environment, health, and safety), or of a similar name, such as HQSE that would include quality assurance.\nIn the second part of the 20th century, automation started with numerical control (NC) automation, and computer numerical control (CNC).\nDigital instruments for quality control and inspection become widely available, and the utilization of lasers for precision measurements became more common for the larger shops that can afford the equipment.\nFurther integration of information technology into machine tools lead to the beginning of computer-integrated manufacturing. Production design and production became integrated into CAD/CAM, and production control became integrated in enterprise resource planning.\n21st century.\nIn the late of the 20th century, the introduction of industrial robots further increased factory automation. Typical applications of robots include welding, painting, assembly, pick and place (such as packaging, palletizing and SMT), product inspection, and testing. As a result of this introduction the machine shop also \"has been modernized to the extent that robotics and electronic controls have been introduced into the operation and control of machines. For small machine shops, though, having robots is more of an exception.\nMachine shop topics.\nMachines.\nA machine is a tool containing one or more parts that uses energy to perform an intended action. Machines are usually powered by mechanical, chemical, thermal, or electrical means, and are often motorized. Historically, a power tool also required moving parts to classify as a machine. However, the advent of electronics has led to the development of power tools without moving parts that are considered machines.\nMachining.\nMachining is any of the various processes in which a piece of raw material is cut into a desired final shape and size by a controlled material-removal process. The many processes that have this common theme, controlled material removal, are today collectively known as subtractive manufacturing, in distinction from processes of controlled material addition, which are known as additive manufacturing. Exactly what the \"controlled\" part of the definition implies can vary, but it almost always implies the use of machine tools (in addition to just power tools and hand tools).\nThough not all machine shops may have a CNC milling center, commonly, they may have access to a manual milling machine.\nMachine tools.\nA machine tool is a machine for shaping or machining metal or other rigid materials, usually by cutting, boring, grinding, shearing, or other forms of deformation. Machine tools employ some sort of tool that does the cutting or shaping. All machine tools use some means of constraining the workpiece and provide a guided movement of the parts of the machine. Thus the relative movement between the workpiece and the cutting tool is controlled or constrained by the machine to at least some extent, rather than being entirely \"offhand\" or \"freehand\".\nCutting tools.\nProfessional management of the inventory of cutting tools occurs mainly in larger operations. Smaller machine shops may have a more limited assortment of endmills, keyseat cutters, inserts, and other cutting tools. The choice in the sophistication of the design of the cutting tool, including material and finish, commonly depends on the job and the price of the cutting tool. In some instances, the cost of custom-made tools could be prohibitive for a small shop.\nDepending on the industry and demands of the job, a cutting tool may only be used on a certain type of material, that is, a cutting tool may not contact another workpiece made of different chemical composition.\nNot all machine shops are equipped with a mill and not all machine shops are aimed to do milling work.\nHousekeeping.\nSome machine shops are better organized than others, and some places are kept cleaner than other establishments. In some instances, the shop is swept minutes before the end of every shift, and in other cases, there's no schedule or routine, or the cycle for sweeping and cleaning is more relaxed.\nWhen it comes to machines, in some places the care and maintenance of the equipment are paramount, and the swarf (commonly known as chips) produced after parts have been machined, are removed daily, and then the machine is air-blown and wiped clean; while in other machine shops, the chips are left in the machines until is an absolute necessity to remove them; the second instance is not advisable.\nRecycling.\nThe remanent or residue of materials used, such as aluminum, steel, and oil, among others, can be gathered and recycled, and commonly, it may be sold. However, not all machine shops practice recycling, and not all have personnel dedicated to enforcing the habit of separating and keeping materials separated. In larger and organized operations, such responsibility may be delegated to the Health, Safety, Environment, and Quality (HSEQ) department.\nInspection.\nQuality assurance, quality control and inspection, are terms commonly used interchangeably. The accuracy and precision to be attained depends on several determining factors. Since not all machines have the same level of reliability and capability to execute predictable finished results within certain tolerances, nor all manufacturing processes achieve the same range of exactness, the machine shop is then limited to its own dependability in delivering the desire outcomes. Subsequently, subject to the rigor declared by the customer, the machine shop may be required to undergo a verification and validation even prior to the issuance and acknowledgment of an order.\nThe machine shop may have a specific area established for measuring and inspecting the parts in order to confirm compliance, while other shops only rely on the inspections performed by the machinists and fabricators. For instance, in some shops, a granite, calibrated surface plate may be shared by different departments, and in other shops, the lathes, the mills, etc, may have their own, or may not have one at all.\nCalibration.\nThe standards followed, the industry served, quality control, and mainly the type of practices in the machine shop, will denote the utilization of precision inspection instruments, and the accuracy of metrology employed. This means that not all machine shops implement a periodic interval for calibrating measuring devices. Not all machine shops have the same type of measuring instruments, though it is common to find micrometers, Vernier calipers, granite surface plates, among others.\nThe frequency and precision for calibrating metrology instruments may vary and it may require hiring the services of a specialized third-party. Also, in some instances, maintaining all instruments existent in the shop calibrated may be a requirement to not fall out of compliance.\nLayout.\nThe location and orientation of the machines are important. Preferably, some prior thought has been given in the positioning of the equipment; likely not as meticulously as in a plant layout study, the closeness of the machines, the types of machines, were the raw material are received and kept, as well as other factors, including ventilation, are taken in account to establish the initial layout of the machine shop. A routing diagram and daily operations may dictate the need to rearrange.\nProfitability is commonly a driving consideration in regards to maximizing production, and thus aligning the machines in an effective manner; however, other critical factors must be considered, such as the preventive maintenance of the equipment and safety in the workplace. For instance, allowing room for a technician to maneuver behind the machining center to inspect connections, and not placing the machine where it would block the emergency exit.\nStorage rooms and tool cribs.\nSome shops have cages or rooms dedicated to keeping certain tools or supplies; for instance, a room may be dedicated to only welding supplies, gas tanks, etcetera; or where janitorial supplies or other consumables such as grinding disks are stored. Depending on the size of the operation, management, and controls, these areas may be restricted and locked, or these could be manned by an employee, as by a tool crib attendant; in other instances, the storage rooms or cages are accessible to all personnel. Not all shops have a tool crib or storage room(s) though, and in many cases, a large cabinet suffices.\nHand tools.\nAlso, the way hand tools are stored and are made available to the fabricator or operators depends on how the shop functions or is managed. In many cases, common hand tools are visible in the work area and at reach for anyone. In many cases, the workers do not need to provide their own tools since the daily tools are available and provided, but in many other cases, the workers bring their own tools and toolboxes to their workplace\nSafety.\nSafety is a consideration that needs to be observed and enforced daily and constantly; however, a shop may vary from other shops in strictness and thoroughness when it comes to the actual practice, policies implemented and overall seriousness ascertained by the personnel and management. In an effort to standardize some common guidelines, in the United States, the Occupational Safety and Health Administration (OSHA) issues didactic material and enforces precautions with the goal of preventing accidents.\nIn a machine shop usually, there are numerous practices that are known in relation to working safely with machines. Some of the common practices include:\nSafety precautions in a machine shop are aimed to avoid injuries and tragedies, for example, to eliminate the possibility of a worker being fatally harmed by being entangled in a lathe.\nMany machines have safety measurements as built-in parts of their design; for example, an operator must press two buttons which are out of the way for a press or punch to function, and thus not pinch the operator's hands.", "Engineering,_Manufacturing": 0.9998937845, "qwen": "Yes"}
{"id": "8198501", "revid": "32990417", "url": "https://en.wikipedia.org/wiki?curid=8198501", "title": "Crash box (stagecraft)", "text": "A crash box is a device which reproduces a crash or collision sound effect. Commonly used in theatre, they consist of a large metal or wood crate in which glassware, china crockery, wood blocks or other delicate objects are placed. The items may or may not be broken. Crash boxes can usually be used multiple times, until the objects inside of them become so broken that they no longer give the desired effect. They can then be reloaded with more breakable objects and reused. Crash boxes are used to recreate the sounds of a crash, collision or glass breakage in theatre. To recreate the sound effects, crash boxes are dropped from a height backstage. They can also be shaken to create a gentler sound effect. A crash box is generally preferred to a recorded sound effect because it is perceived as more realistic.", "Engineering,_Manufacturing": 0.9991446137, "qwen": "Yes"}
{"id": "30502980", "revid": "43392054", "url": "https://en.wikipedia.org/wiki?curid=30502980", "title": "Product layout", "text": "In manufacturing engineering, a product layout refers to a production system where the work stations and equipment are located along the line of production, as with assembly lines.\nUsually, work units are moved along line (not necessarily a geometric line, but a set of interconnected work stations) by a conveyor. Work is done in small amounts at each of the work stations on the line. To use the product layout, the total work to be performed must be dividable into small tasks that can be assigned to each of the workstations.\nBecause the work stations each do small amounts of work, the stations utilize specific techniques and equipment tailored to the individual job they are assigned. This can lead to a higher rate of production.", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "30504788", "revid": "21706178", "url": "https://en.wikipedia.org/wiki?curid=30504788", "title": "Manufacturing cost", "text": "Manufacturing cost is the sum of costs of all resources consumed in the process of making a product. The manufacturing cost is classified into three categories: direct materials cost, direct labor cost and manufacturing overhead. It is a factor in total delivery cost.\nDirect materials cost.\nDirect materials are the raw materials that become a part of the finished product. Manufacturing adds value to raw materials by applying a chain of operations to maintain a deliverable product. There are many operations that can be applied to raw materials such as welding, cutting and painting. It is important to differentiate between direct materials and indirect materials.\nDirect labour cost.\nThe direct labour cost is the cost of workers who can be easily identified with the unit of production. Types of labour who are considered to be part of the direct labour cost are the assembly workers on an assembly line.\nManufacturing overhead.\nManufacturing overhead is any manufacturing cost that is neither direct materials cost nor direct labour cost. Manufacturing overhead includes all charges that provide support to manufacturing.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "30519429", "revid": "11677590", "url": "https://en.wikipedia.org/wiki?curid=30519429", "title": "Skid mount", "text": "A Skid mount is a popular method of distributing and storing machinery and usually-stationary equipment for the military and industry on its own or with other units as part of a modular system (modular process skid). The machinery at point of manufacture is permanently mounted in a frame or onto rails or a metal Pallet. The equipment can then be easily secured and transported and used as a unit. A unit such as a fire-fighting Skid unit may also be temporarily placed onto a vehicle to equip it for a task. They often have standard sized holes (called \"pockets\") for a forklift truck to slide into it to lift it safely.\nIt could be thought of as a permanently attached Pallet (also known as a skid).\nAs well as making it more transportable, it adds stability when static.\nTo facilitate factory floor efficiency, machinery such as laser welders, plastic injection molding units, lathes and sewing machines are often skid mounted for easy placement according to work flow needs. ", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "4408335", "revid": "307355", "url": "https://en.wikipedia.org/wiki?curid=4408335", "title": "Optical lens design", "text": "Optical lens design is the process of designing a lens to meet a set of performance requirements and constraints, including cost and manufacturing limitations. Parameters include surface profile types (spherical, aspheric, holographic, diffractive, etc.), as well as radius of curvature, distance to the next surface, material type and optionally tilt and decenter. The process is computationally intensive, using ray tracing or other techniques to model how the lens affects light that passes through it.\nDesign requirements.\nPerformance requirements can include:\nDesign constraints can include realistic lens element center and edge thicknesses, minimum and maximum air-spaces between lenses, maximum constraints on entrance and exit angles, physically realizable glass index of refraction and dispersion properties.\nManufacturing costs and delivery schedules are also a major part of optical design. The price of an optical glass blank of given dimensions can vary by a factor of fifty or more, depending on the size, glass type, index homogeneity quality, and availability, with BK7 usually being the cheapest. Costs for larger and/or thicker optical blanks of a given material, above 100–150 mm, usually increase faster than the physical volume due to increased blank annealing time required to achieve acceptable index homogeneity and internal stress birefringence levels throughout the blank volume. Availability of glass blanks is driven by how frequently a particular glass type is made by a given manufacturer, and can seriously affect manufacturing cost and schedule.\nProcess.\nLenses can first be designed using paraxial theory to position images and pupils, then real surfaces inserted and optimized. Paraxial theory can be skipped in simpler cases and the lens directly optimized using real surfaces. Lenses are first designed using average index of refraction and dispersion (see Abbe number) properties published in the glass manufacturer's catalog and through glass model calculations. However, the properties of the real glass blanks will vary from this ideal; index of refraction values can vary by as much as 0.0003 or more from catalog values, and dispersion can vary slightly. These changes in index and dispersion can sometimes be enough to affect the lens focus location and imaging performance in highly corrected systems.\nThe lens blank manufacturing process is as follows:\nThe glass blank pedigree, or \"melt data\", can be determined for a given glass batch by making small precision prisms from various locations in the batch and measuring their index of refraction on a spectrometer, typically at five or more wavelengths. Lens design programs have curve fitting routines that can fit the melt data to a selected dispersion curve, from which the index of refraction at any wavelength within the fitted wavelength range can be calculated. A re-optimization, or \"melt re-comp\", can then be performed on the lens design using measured index of refraction data where available. When manufactured, the resulting lens performance will more closely match the desired requirements than if average glass catalog values for index of refraction were assumed.\nDelivery schedules are impacted by glass and mirror blank availability and lead times to acquire, the amount of tooling a shop must fabricate prior to starting on a project, the manufacturing tolerances on the parts (tighter tolerances mean longer fab times), the complexity of any optical coatings that must be applied to the finished parts, further complexities in mounting or bonding lens elements into cells and in the overall lens system assembly, and any post-assembly alignment and quality control testing and tooling required. Tooling costs and delivery schedules can be reduced by using existing tooling at any given shop wherever possible, and by maximizing manufacturing tolerances to the extent possible.\nLens optimization.\nA simple two-element air-spaced lens has nine variables (four radii of curvature, two thicknesses, one airspace thickness, and two glass types). A multi-configuration lens corrected over a wide spectral band and field of view over a range of focal lengths and over a realistic temperature range can have a complex design volume having over one hundred dimensions.\nLens optimization techniques that can navigate this multi-dimensional space and proceed to local minima have been studied since the 1940s, beginning with early work by James G. Baker, and later by Feder, Wynne, Glatzel, Grey and others. Prior to the development of digital computers, lens optimization was a hand-calculation task using trigonometric and logarithmic tables to plot 2-D cuts through the multi-dimensional space. Computerized ray tracing allows the performance of a lens to be modelled quickly, so that the design space can be searched rapidly. This allows design concepts to be rapidly refined. Popular optical design software includes Zemax's OpticStudio, Synopsys's Code V, and Lambda Research's OSLO. In most cases the designer must first choose a viable design for the optical system, and then numerical modelling is used to refine it. The designer ensures that designs optimized by the computer meet all requirements, and makes adjustments or restarts the process when they do not.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "43154679", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=43154679", "title": "Factory automation infrastructure", "text": "Factory automation infrastructure describes the process of incorporating automation into the manufacturing environment and processing of input goods into final products. \nThe manufacturing environment is defined by its ability to manufacture and/or assemble goods by machines, integrated assembly lines, and robotic arms. Automated environments are also defined by their coordination with (and usually their systematic integration with) the required automatic equipment to form a complete system. \nFactory automation intends to decrease risks associated with laborious and dangerous work faced by human workers. This system is essentially a solution for the automation and manufacturing of a particular production process of an intended output and/or final/end product.\nAutomation.\nAutomation has produced sophisticated parts with similar or higher output qualities with minor quality fluctuation. It also can help cut overall manufacturing costs and create safer working environments for workers. \nThe use of automation in manufacturing started by using technologies such as pneumatic and hydraulic systems in applications where their mechanical advantages could be used to raise output quality and efficiency in production. Complex and highly integrated systems have since evolved, composed of many different technologies and innovative procedures controlled under High Language programming environments with sophisticated operation drivers. These drivers often are running languages that support 6, 7, and 8-axis controls for sophisticated robotics.\nRobotic arm.\nA robotic arm is a type of mechanical arm, usually programmable, with functions similar to a human arm; the arm may be the total of the mechanism or may be part of a more complex robot. The links of such a manipulator are connected by joints allowing either rotational motion (such as in an articulated robot) or transnational (linear) displacement. The links of the manipulator can be considered to form a kinematic chain. The terminus of the kinematic chain of the manipulator is called the end effector and is analogous to the human hand.\nAdvantages and disadvantages.\nThe main advantages of automation are:\nThe following methods are often employed to improve productivity, quality, or robustness.\nThe main disadvantages of automation are:\nExternal links.\nkinematic chain. ", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "5195650", "revid": "1368779", "url": "https://en.wikipedia.org/wiki?curid=5195650", "title": "Profile (engineering)", "text": "In standardization, a profile is a subset internal to a specification. Aspects of a complex technical specification may necessarily have more than one interpretation, and there are probably many optional features. These aspects constitute a profile of the standard. Two implementations engineered from the same description may not interoperate due to having a different profile of the standard. Vendors can even ignore features that they view as unimportant, yet prevail in the long run. \nThe use of profiles in these ways can force one interpretation, or create de facto standards from official standards. Engineers can design or procure by using a profile to ensure interoperability. For example, the International Standard Profile, ISP, is used by the ISO in their ISO ISP series of standards; in the context of OSI networking, Britain uses the UK-GOSIP profile and the US uses US-GOSIP; there are also various mobile profiles adopted by the W3C for web standards. In particular, implementations of standards on mobile devices often have significant limitations compared to their traditional desktop implementations, even if the standard which governs both permits such limitations. \nIn structural engineering a profile means a hot rolled structural steel shape like an -beam.\nIn civil engineering, a profile consists of a plotted line which indicates grades and distances (and typically depths of cut and/or elevations of fill) for excavation and grading work. Constructors of roadways, railways (and similar works) normally chart the profile along the centerline. A profile can also indicate the vertical slope(s) (changes in elevation) in a pipeline or similar structure. Civil engineers always depict profile as a side (cross section) view (as opposed to an overhead (plan) view).\nMaterial fabrication.\nIn fabricating, a profile consists of the more-or-less complex outline of a shape to be cut in a sheet of material such as laminated plastic, aluminium alloy or steel plate. In modern practice, a drawing office determines the shape and dimensions required to fit the sheet into a larger work and feeds directions to a computer controlling a profile cutter. This then cuts the shape from a standard-sized sheet. The cutting head may use a rotating cutter like that of a spindle router or (in the case of steel plate) a torch which burns oxy-acetylene or other oxy-gas. ", "Engineering,_Manufacturing": 1.0000047684, "qwen": "Yes"}
{"id": "8304759", "revid": "5795946", "url": "https://en.wikipedia.org/wiki?curid=8304759", "title": "Printing registration", "text": "In color printing, print registration is the layering of printed patterns to form a multicolor pattern. Registration error is the \"position misalignment in the overlapped patterns.\" Machine components such as the print cylinder, doctor blade assembly, printing plates, stress/friction and more, affect the registration of the machine. Inconsistencies among these components can cause the printing press to fall out of registration; that is when press operators will begin to see defects in their print. There are many different ways to achieve proper registration, many of which employ the alignment of registration marks (pictured right). Many press manufacturers have installed automatic register systems to assist the operator in getting the print back into proper alignment.\nPurpose.\nWhen printing an image or a package of some sort that has more than one color, it is necessary to print each color separately and ensure each color overlaps the others precisely. If this is not done, the finished image will look fuzzy, blurred or \"out of register\" (see image to right). If one or more print units, plate or other print component is out of registration, the result can be printed colors in the wrong areas, overprint or white space. With proper registration, there will be no white space, out of margin colors, or confusing overlap of images in the print. To help line the colors up correctly, a registration system is necessary.\nRemedies.\nTrapping.\nA remedy for slight misregistration is trapping. Trapping is a method of adjusting areas where two distinct, adjacent colors meet so that press misregistration won't cause white spaces. Where two colours abut, the lighter colour is slightly expanded into the darker to create an overlap. This yields a darker outline, which is considered less objectionable than a white gap. A major exception to this is the case when opaque (colors that completely obscure colors printed beneath them) spot colors are used. Other colors, regardless of their relative luminance, are always trapped to (spread under) these spot colors. If several of these spot colors are used (a common practice in the packaging market), the order of printing layers rather than luminance is the decisive element: the first color to be printed is spread under the next color. The trap width is dictated by the maximum amount of misregistration of the entire workflow up to the press.\nOverprinting.\nBlack ink is set to \"overprint\" colors in the background. The difference is not visible since the lighter color is spread underneath the—almost—opaque black.\nTypes of (stone) lithography registration.\nThere are many different styles of registration for many different types of printing. These deal with stone lithography, as used in fine arts printmaking.\nT-bar.\nThis method, using small measured registration marks on both the stone and the paper, is very accurate and simple to do. The printer measures the exact size of the paper and the desired margins. Then marks are made at both ends of the sheet of paper, and corresponding marks (usually in the shape of a \"T\") are made on the stone. Then the printer matches the marks on the paper to those on the stone. This way many runs of different colors can be pulled exactly in line with one another, each of them measured from the same system of marks.\nPin-hole.\nThis method involves laying the paper on the un-inked surface, and making a pin-hole through both the bottom and top of the paper, being careful to make a mark in the stone's surface. Then the locations of the holes are transferred to each sheet of paper to be printed. When printing, one should place pins in each hole of a sheet of paper, and lower it onto the inked stone, placing each pin in its respective hole in the stone. This method can ruin paper by creating holes and if the holes get too large, they lose their function as registration devices.\nEyeballing.\nThis method relies solely on hand–eye coordination. Eyeballing can be found in other industries as well. The printer places the paper over the stone-image, measuring and judging registration by eye. This is not very consistent, depending on the person. ", "Engineering,_Manufacturing": 0.995265007, "qwen": "Yes"}
{"id": "4911272", "revid": "19921271", "url": "https://en.wikipedia.org/wiki?curid=4911272", "title": "Disco Corporation", "text": " is a Japanese precision tools maker, especially for the semiconductor production industry.\nThe company makes dicing saws and laser saws to cut semiconductor silicon wafers and other materials; grinders to process silicon and compound semiconductor wafers to ultra-thin levels; polishing machines to remove the grinding damage layer from the wafer back-side and to increase chip strength. \nHistory.\nThe company was founded as Daiichi-Seitosho in May 1937, as an industrial abrasive wheel manufacturer.\nAfter World War II Japan faced a construction boom which also helped DISCO to boost its sales. The company's grinder discs were in high demand from utility companies, which needed them to manufacture watt-meters.\nIn December 1968 the company developed and released an ultra-thin resinoid cutting wheel, \"Microncut\". The wheel contained diamond powder and as a result it was capable of making sharp, precision cuts as demanded in the semiconductor manufacturing process. There were no cutting machines available in the market on which ultra-thin precision wheels could be mounted and run, DISCO decided to develop its own machine in 1975. The cutting machine, DAD-2h, received instant recognition from semiconductor companies, including Texas Instruments.\nThe company adopted the name of DISCO Corporation in May 1977, was listed with the Japan Securities Dealers' Association in October 1989, and entered the First Section of the Tokyo Stock Exchange in December 1999.", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "4918282", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=4918282", "title": "1996–97 UEFA Cup", "text": "The 1996–97 UEFA Cup was the 26th season of the UEFA Cup, the third-tier club football competition organised by the Union of European Football Associations (UEFA). It was won by German side Schalke 04, who beat Internazionale of Italy on penalties after the two-legged final finished 1–1 on aggregate. Defending champions Bayern Munich were eliminated in the first round by Valencia.\nThis was the last year in which the UEFA Cup final was played in a two-legged, home-and-away format. From 1998, the final was played as a single match at a neutral venue.\nFormat.\nAccording to 1995 UEFA ranking, Bulgaria ceded a slot to Norway.\nThe access list was finally increased to 117 clubs:\nA second qualifying round was consequently added for the first time in the history of the European competitions.\nTeams.\nThe labels in the parentheses show how each team qualified for the place of its starting round:\nPreliminary round.\nSecond leg.\n\"Dinamo Tbilisi won 6–2 on aggregate.\"\n\"Dinamo-93 Minsk won 4–2 on aggregate.\"\n\"Croatia Zagreb won 10–2 on aggregate.\"\n\"Sliema Wanderers won 4–3 on aggregate.\"\n\"FC Jazz won 4–1 on aggregate.\"\n\"Vardar won 3–1 on aggregate.\"\n\"Anorthosis Famagusta won 6–2 on aggregate.\"\n\"Vojvodina won 5–1 on aggregate.\"\n\"HJK won 6–5 on aggregate.\"\n\"Lantana Tallinn won 2–1 on aggregate.\"\n\"1–1 on aggregate; Dinamo Minsk won on away goals.\"\n\"Beitar Jerusalem won 8–2 on aggregate.\"\n\"Legia Warsaw won 7–2 on aggregate.\"\n\"Slavia Sofia won 5–4 on aggregate.\"\n\"ÍA won 2–1 on aggregate.\"\n\"Lokomotiv Sofia won 7–2 on aggregate.\"\n\"Skonto won 7–1 on aggregate.\"\n\"Hajduk Split won 6–1 on aggregate.\"\n\"APOEL won 9–3 on aggregate.\"\n\"Barry Town won 2–1 on aggregate.\"\n\"Žalgiris Vilnius won 3–2 on aggregate.\"\n\"Košice won 6–2 on aggregate.\"\n\"Haka won 3–2 on aggregate.\"\n\"Mura won 2–0 on aggregate.\"\n\"Hutnik Kraków won 11–2 on aggregate.\"\n\"Partizan won 4–1 on aggregate.\"\n\"Slovan Bratislava won 5–3 on aggregate.\"\nQualifying round.\nSecond leg.\n\"Dynamo Moscow won 4–2 on aggregate.\"\n\"Rapid București won 2–0 on aggregate.\"\n\"Neuchâtel Xamax won 6–1 on aggregate.\"\n\"Halmstad won 1–0 on aggregate.\"\n\"Grazer AK won 7–1 on aggregate.\"\n\"Legia Warsaw won 4–1 on aggregate.\"\n\"APOEL won 3–1 on aggregate.\"\n\"Helsingborg won 4–1 on aggregate.\"\n\"CSKA Moscow won 6–1 on aggregate.\"\n\"Odense won 9–1 on aggregate.\"\n\"Aberdeen won 5–4 on aggregate.\"\n\"4–4 on aggregate; Barry Town won 4–2 on penalties.\"\n\"Hutnik Kraków won 3–2 on aggregate.\"\n\"Trabzonspor won 5–3 on aggregate.\"\n\"Național București won 1–0 on aggregate.\"\n\"Aarau won 4–2 on aggregate.\"\n\"3–3 on aggregate; Spartak Moscow won on away goals.\"\n\"Tirol Innsbruck won 5–2 on aggregate.\"\n\"Torpedo Moscow won 2–1 on aggregate.\"\n\"Bodø/Glimt won 7–2 on aggregate.\"\n\"Lyngby won 2–0 on aggregate.\"\n\"Celtic won 1–0 on aggregate.\"\n\"Chornomorets Odesa won 4–2 on aggregate.\"\n\"Dinamo Tbilisi won 2–1 on aggregate.\"\n\"Malmö won 4–1 on aggregate.\"\n\"Beşiktaş won 3–2 on aggregate.\"\nFirst round.\nSecond leg.\n\"Feyenoord won 2–1 on aggregate.\"\n\"Ferencváros won 5–3 on aggregate.\"\n\"Slavia Prague won 5–2 on aggregate.\"\n\"Beşiktaş won 3–0 on aggregate.\"\n\"Hamburg won 4–0 on aggregate.\"\n\"Național București won 2–0 on aggregate.\"\n\"Metz won 1–0 on aggregate.\"\n\"Brøndby won 7–0 on aggregate.\"\n\"Club Brugge won 3–1 on aggregate.\"\n\"4–4 on aggregate; Boavista won on away goals.\"\n\"Valencia won 3–1 on aggregate.\"\n\"Roma won 6–1 on aggregate.\"\n\"Neuchâtel Xamax won 2–1 on aggregate.\"\n\"Schalke 04 won 5–2 on aggregate.\"\n\"Lazio won 2–1 on aggregate.\"\n\"Internazionale won 4–1 on aggregate.\"\n\"Aberdeen won 6–4 on aggregate.\"\n\"Sporting CP won 2–1 on aggregate.\"\n\"Trabzonspor won 5–2 on aggregate.\"\n\"Espanyol won 3–2 on aggregate.\"\n\"1–1 on aggregate; Helsingborg won on away goals.\"\n\"3–3 on aggregate; Grazer AK won on away goals.\"\n\"Newcastle United won 5–2 on aggregate.\"\n\"Anderlecht won 5–2 on aggregate.\"\n\"Vitória Guimarães won 3–2 on aggregate.\"\n\"Dinamo Tbilisi won 2–1 on aggregate.\"\n\"Tenerife won 4–3 on aggregate.\"\n\"Borussia Mönchengladbach won 6–4 on aggregate.\"\n\"AS Monaco won 4–1 on aggregate.\"\n\"Spartak Moscow won 5–3 on aggregate.\"\n\"4–4 on aggregate; Legia Warsaw won on away goals.\"\n\"Karlsruhe won 4–2 on aggregate.\"\nSecond round.\nSecond leg.\n\"Boavista won 5–1 on aggregate.\"\n\"Newcastle United won 6–3 on aggregate.\"\n\"Club Brugge won 3–1 on aggregate.\"\n\"1–1 on aggregate; Anderlecht won on away goals.\"\n\"Metz won 3–2 on aggregate.\"\n\"Feyenoord won 3–1 on aggregate.\"\n\"Brøndby won 2–0 on aggregate.\"\n\"Valencia won 1–0 on aggregate.\"\n\"Tenerife won 5–4 on aggregate.\"\n\"1–1 on aggregate; Internazionale won 5–3 on penalties.\"\n\"Helsingborg won 3–1 on aggregate.\"\n\"Beşiktaş won 3–2 on aggregate.\"\n\"Schalke 04 won 4–3 on aggregate.\"\n\"AS Monaco won 4–3 on aggregate.\"\n\"Karlsruhe won 4–2 on aggregate.\"\n\"Hamburg won 5–2 on aggregate.\"\nThird round.\nSecond leg.\n\"Brøndby won 6–3 on aggregate.\"\n\"Schalke 04 won 3–2 on aggregate.\"\n\"AS Monaco won 5–0 on aggregate.\"\n\"Anderlecht won 1–0 on aggregate.\"\n\"Valencia won 5–3 on aggregate.\"\n\"Newcastle United won 3–1 on aggregate.\"\n\"Internazionale won 7–1 on aggregate.\"\n\"Tenerife won 4–2 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"Tenerife won 2–1 on aggregate.\"\n\"AS Monaco won 4–0 on aggregate.\"\n\"Internazionale won 3–2 on aggregate.\"\n\"Schalke 04 won 3–1 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Internazionale won 3–2 on aggregate.\"\n\"Schalke 04 won 2–1 on aggregate.\"\nFinal.\nSecond leg.\n\"1–1 on aggregate; Schalke 04 won 4–1 on penalties.\"\nTop scorers.\nThe top scorers from the 1996–97 UEFA Cup are as follows:", "Engineering,_Manufacturing": 0.9986202717, "qwen": "Yes"}
{"id": "4927657", "revid": "19531195", "url": "https://en.wikipedia.org/wiki?curid=4927657", "title": "Spray forming", "text": "Spray forming, also known as spray casting, spray deposition and in-situ compaction, is a method of casting near net shape metal components with homogeneous microstructures via the deposition of semi-solid sprayed droplets onto a shaped substrate. In spray forming an alloy is melted, normally in an induction furnace, then the molten metal is slowly poured through a conical tundish into a small-bore ceramic nozzle. The molten metal exits the furnace as a thin free-falling stream and is broken up into droplets by an annular array of gas jets, and these droplets then proceed downwards, accelerated by the gas jets to impact onto a substrate. The process is arranged such that the droplets strike the substrate whilst in the semi-solid condition, this provides sufficient liquid fraction to 'stick' the solid fraction together. Deposition continues, gradually building up a spray formed billet of metal on the substrate.\nThe \"gas atomised spray forming\" (\"GASF\") process typically has a molten alloy flow rate of 1–20 kg/min, although twin atomizer systems can achieve metal flow rates of up to 80 kg/min. Special steel billets of 1 tonne or more have been produced by spray forming on a commercial basis, together with Ni super-alloy ring blanks of up to 500 kg and Al alloy extrusion billets of up to 400 kg.\nHistory.\nProfessor Singer at the Swansea University first developed the idea of gas atomised spray forming in the 1970s in which a high pressure gas jet impinges on a stable melt stream to cause atomisation. The resulting droplets are then collected on a target, which can be manipulated within the spray and used to form a near-dense billet of near-net shape. Spray forming has found applications in specialist industries such as: stainless steel cladding of incinerator tubes; nickel superalloy discs and rings for aerospace-engines; aluminium-titanium, aluminium-neodymium and aluminium-silver sputter targets; aluminium-silicon alloys for cylinder liners; and high speed steels. The history of spray forming is an example of how the creative contributions of many researchers were necessary over a number of years to produce the innovation of a now widely used industrial process. \nAdvantages.\nSpray forming offers certain advantages over both conventional ingot metallurgy and more specialized techniques such as powder metallurgy. Firstly, it is a flexible process and can be used to manufacture a wide range of materials, some of which are difficult to produce by other methods, e.g. Al-5wt% Li alloys or Al-SiC, Al-Al2O3 metal matrix composites (MMCs). The atomisation of the melt stream into droplets of 10-500 μm diameter, some of which, depending on diameter, cool quickly to the solid and semi-solid state provide a large number of nucleants for the residual liquid fraction of the spray formed material on the billet top surface. The combination of rapid cooling in the spray and the generation of a large population of solid nucleants in the impacting spray leads to a fine equiaxed microstructure, typically in the range 10–100 μm, with low levels and short length scales of internal solute partitioning. These microstructural aspects offer advantages in material strength because of fine grain size, refined distribution of dispersoid and/or secondary precipitate phases, as well as tolerance to impurity 'tramp' elements. This fine structure in the 'as sprayed' condition means homogenising heat treatments can often be avoided. Because of the complex solidification path (i.e. the rapid transition from superheated melt to solid, liquid or semi-solid droplet to temperature equilibration at semi-solid billet top and final slow cooling to fully solid) of the spray formed material, extended solubility of alloying elements and the formation of metastable and quasi-crystalline phases has also been reported. \nOne of the major attractions of spray forming is the potential economic benefit to be gained from reducing the number of process steps between melt and finished product. Spray forming can be used to produce strip, tube, ring, clad bar / roll and cylindrical extrusion feed stock products, in each case with a relatively fine-scale microstructure even in large cross-sections. The benefits of GASF over powder metallurgy accrue from the reduced number of process steps where powder sieving, pressing, de-gassing and handling steps and their attendant safety and contamination issues may be removed.\nDisadvantages.\nThere are two major disadvantages to the gas atomisation spray forming process. The most significant disadvantage is the relatively low process yield with typical losses of ~30%. Losses occur because of overspray (droplets missing the emerging billet), splashing of material from the billet surface, and material 'bouncing' off the semi-solid top surface. Many operators of the spray forming process now use a particle injector system to re-inject the overspray powder, and thus recycle material that would otherwise be lost, or sell the overspray powder as a product in its own right. The second major disadvantage is one of process control. As it is essentially a free-forming process with many interdependent variables, it has proved difficult to predict the shape, porosity or deposition rate for a given alloy. Much of the control is based on operator experience and empirical relationships. It is partly the process complexity and lack of robust process control that has prevented the widespread commercialisation of this process. Some developments using feed-back control have proved successful in improving the variations in billet diameter and improving yield in specific systems but these have yet to find widespread implementation. \nPorosity resulting from gas entrapment and solidification shrinkage is a significant problem in spray formed materials. A typical spray formed billet will contain 1-2% porosity with a pore size dependent on alloy freezing range and various process parameters. Hot isostatic pressing (HIP) or thermo-mechanical processing can heal these pores if they are small (less than 30 μm). Despite these disadvantages, spray forming remains an economic process for the production of difficult to manufacture, niche alloys. Large-scale porosity is more difficult to heal effectively and must be minimised by careful process control. In some cases, porosity is controlled by alloy additions which react with dissolved and entrapped gas to form a solid phase, e.g. titanium added to copper billets to form titanium nitride with dissolved and entrapped nitrogen gas. Porosity, even after consolidation, can limit the applications of spray formed material, for example rotating gas turbine components must have zero porosity because of the detrimental effect on high-cycle fatigue (HCF).\nCommercialisation.\nIn spite of the problems associated with the spray forming process there has been sustained industrial interest in spray forming over the last 35 years. Sandvik-Osprey (former Osprey Metals Ltd) of Neath, South Wales holds the patents on the process and have licensed the technology to a range of industries. There are currently approximately 25 licensees operating around the world, ranging from small research and development plants to full-scale commercial operations. Main applications are prematerial for low temperature Nb3Sn super conductors (CuSn), oil drilling equipment (high strength material CuMnNi) and for forming tools (CuAlFe with high Al-content). In all of these applications, research concerns the reconciliation of the cost disadvantages and complexity of spray forming with the demand for high performance alloys in niche applications.\nMelting.\nThe earliest spray forming work was based on a resistively heated electric holding furnace. The melt then passed through a 3 mm diameter Al2O3 nozzle. However the low flow rate made a high superheat necessary to prevent solidification in the nozzle. The next generation melting procedures in spray forming applications were bottom pour induction units, which offer many benefits. In this system, the melting crucible is directly above the atomiser head with a ceramic nozzle feeding directly from the furnace to the atomiser. A stopper rod runs through the melt to the top of the pouring nozzle, the rod is withdrawn when the melt reaches the designated temperature for spraying, typically above the alloy's liquidus. Alternatively a pre-prepared plug of alloy to block the nozzle is used, and at a specified superheat this plug melts allowing the contents of the furnace to drain through the nozzle. Another problem associated with bottom pour furnaces is the change in flow rate associated with the reducing metalo-static head in the crucible. In some cases, introducing an inert gas overpressure during pouring can compensate for this effect. \nAn alternative approach is the tilt-pour furnace whereby an induction furnace is tilted to pour the melt into a conical tundish that in turn delivers the molten metal to the melt delivery nozzle. The tilt pour system provides the advantage that melting is decoupled from the spraying procedure so that melting problems and remedial solutions do not affect or disturb the critical set-up of the melt delivery nozzle.\nIn the most complex melting arrangement, used only for production of nickel superalloy turbine forging blanks by spray forming, vacuum induction melting, electroslag re-melting and cold hearth crucibles have been combined by GE to control alloy impurity levels and the presence of refractory inclusions in the molten metal supply. \"Clean metal spray forming\" (\"CMSF\") combines the electroslag refining process, cold walled induction guide and gas atomised spray forming. This approach has led to a reduction in the number of melt related defects (pores, inclusions, etc.), a finer average grain size, the ability to produce larger ingots and the ability to process a wider range of alloys.\nAtomisation.\nThere are many different techniques for atomisation of molten metals, many of which are derived from the powder metallurgy industry and have been extensively reviewed elsewhere. There are two major atomisation techniques used in spray forming: centrifugal atomisation for the manufacture of near net shape rings and gas atomisation for the manufacture of billets, tube and strip.\nCentrifugal atomisation.\nCentrifugal atomisation involves pouring molten metal at relatively low flow rates (0.1– 2 kg/min) onto a spinning plate, dish or disc, whereby the rotation speed is sufficient to create high centrifugal forces at the periphery and overcome surface tension and viscous forces so the melt is fragmented into droplets. Droplet diameters produced by centrifugal atomisation are dependent primarily on the rotation speed, (up to 20,000 rpm) and are typically in the range 20–1000 μm with cooling rates of the order 104 Ks−1. Centrifugal atomisation is generally conducted under an inert atmosphere of Ar or N2 to prevent oxidation of the fine droplets or can be operated under vacuum.\nGas atomisation.\nThe melt stream exits the melt delivery nozzle into the spray chamber. The melt stream is protected from being destabilised by the turbulent gas environment in the spray chamber by primary gas jets operating at intermediate inert gas pressure of 2 to 4 bar, the resulting gas flow is parallel to the melt stream to stabilise the melt stream. The secondary atomiser uses high velocity (250 to 350 ms−1), high-pressure (6 to 10 bar) gas jets to impinge on the melt stream to achieve atomisation. The atomiser jets are usually arranged as an annulus or as discrete jets positioned symmetrically about the melt delivery nozzle, or less commonly, arranged as a linear nozzle for the production of strip products. Typical droplet diameters follow a log-normal distribution with powder diameters up to ~600 μm with a mass median diameter of ~150 μm. \nThe atomising gas mass flow rate to molten metal mass flow rate ratio is a key parameter in controlling the droplet diameter and hence the cooling rate, billet temperature and resulting solid particle nucleant density. The gas-metal ratio (GMR) is typically in the range 1.5 to 5.5, with yield decreasing and cooling rates in the spray increasing with increasing GMR. Typically at low (1.5) GMR, yield is 75%, if the GMR is increased to 5.0 with all other parameters remaining constant, the process yield is reduced to 60%. \nScanning atomisers have been developed which allow the production of billets of up to 600 mm diameter, approximately twice the diameter possible with a static atomiser. The atomiser head is oscillated mechanically through 5 to 10° at a typical frequency of 25 Hz, to deflect the melt stream creating a spray path that is synchronised with the rotation speed of the collector plate in order to deposit a parallel-sided billet. By using programmable oscillating atomiser drives it was possible to improve the shape and shape reproducibility of spray formed deposits. It has been demonstrated that parallel sided, flat topped billets could be sprayed in a reproducible manner if the substrate rotation and atomiser oscillation frequency were synchronised and optimised for specific alloys and melt flow rates. Twin atomiser systems combine a static and scanning atomiser, making it possible to spray billets of up to 450 mm diameter with economic benefits. \nAtomising gas used in spray forming is generally either N2 and can be either protective or reactive depending on the alloy system, or Ar which is generally entirely inert but more expensive than N2. Reactive gasses can be introduced in small quantities to the atomising gas to create dispersion strengthened alloys e.g. 0.5–10% O2 in N2 used to generate oxide dispersion strengthened (ODS) Al alloys. Comparisons of N2 and Ar based spray forming showed that with all other factors remaining constant, the billet top temperature was lower with N2 than with Ar, because of the differences in thermal diffusivity of the two atomising gases: Ar has a thermal conductivity of 0.0179 W/mK which is approximately a third less than N2 with a thermal conductivity of 0.026 W/mK.\nThe mechanisms of melt break up and atomisation have been extensively researched, showing that atomisation typically consists of 3 steps: (1) primary break up of the melt stream; (2) molten droplets and ligaments undergo secondary disintegration; (3) particles cool and solidify. Theoretical analysis of the atomisation process to predict droplet size has yielded models providing only moderate agreement with experimental data.\nInvestigations show that in all cases gas atomisation of molten metal yields a broad range of droplet diameters, typically in the range 10-600 μm diameter, with a mean diameter of ~100 μm. Droplet diameter governs the dynamic behaviour of the droplet in flight which in turn determines the time available for in-flight cooling which is critical in controlling the resulting billet microstructure. At a flight distance of 300–400 mm, predictions show droplet velocities of 40-90 ms−1 for droplet diameters in the range 20-150 μm respectively, compared to measured velocities of ~100 ms−1, and at distances of up to 180 mm from the atomiser, droplets were still being accelerated by the gas. Droplets cool in-flight predominantly by convection and radiation, and can experience undercooling of up to prior to nucleation. Models and experimental measurements show that small droplets (200 μm will be liquid at deposition. The range of droplet dynamic and thermal histories result in a billet top surface of 0.3 to 0.6 solid fraction. Not all material that impacts the surface is incorporated into the billet: some solid droplets will bounce or splash-off the billet top surface or be directed out of the deposition region by turbulent gas movement in the chamber. The proportion of droplets that impact the surface compared to the proportion that are incorporated into the billet has been termed the \"sticking efficiency\": dependent on the geometric sticking which is a function of the spray angle relative to substrate and the thermal sticking efficiency dependent on spray and billet solid/liquid fraction.\nSpray formed microstructure.\nDuring spraying it is essential to maintain a constant top surface temperature and hence maintain steady-state conditions if a billet with consistent microstructure is to be produced. At the billet surface, during spraying an enthalpy balance must be maintained where the rate of enthalpy lost (Hout) from the billet by conduction to the atomising gas and through the substrate, convection and radiation must be balanced with the rate of enthalpy input (Hin) from the droplets in the spray. There are a variety of factors that can be adjusted in order to maintain these conditions: spray height, atomiser gas pressure, melt flow rate, melt superheat and atomiser configuration, being those parameters most readily adjusted. Typically equipment such as closed circuit cameras and optical pyrometry can be used to monitor billet size/position and top surface temperature. If Hout is much greater Hin then a steady temperature is maintained at the billet top surface. The top surface should be in a mushy condition in order to promote sticking of incoming droplets and partial re-melting of solid particles. The necessary partial re-melting of solid droplets explains the absence of dendritic remnants from pre-solidified droplets in the final microstructure. If Hin is insufficient to cause significant re-melting, a 'splat' microstructure of layered droplets will form, typical of thermal spray processes such as vacuum plasma spraying (VPS), arc spraying and high velocity oxy-fuel. Processing maps have been produced for plasma spraying and spray forming using a steady-state heat balance in terms of the interlayer time (time between deposition events) against average deposition rate per unit area. These maps show the boundaries between banded un-fused microstructure and an equiaxed homogeneous structure.\nThe final phase of solidification occurs once droplets have impacted the mushy billet surface and thermal equilibration has taken place between the droplets and the billet. At this stage residual liquid is present as continuous network delineating polygonal grain boundaries, with a typical liquid fraction of 0.3 – 0.5. The cooling rates during solidification of the billet is several orders of magnitude slower than the cooling rate in the spray, at 1-20 Ks−1. \nAlthough one of the benefits of spray forming is purportedly the ability to produce bulk material with fine scale microsegregation and little or no macrosegregation work on Al-Mg-Li-Cu alloys showed that as a consequence of the interconnected liquid in the billet there was significant macrosegregation in large spray formed wrought Al billets. The distribution of Cu, Mg and Li in, for example, Al alloy 8091 showed surprisingly pronounced macrosegregation with the variation of Cu(wt%) in a spray formed 8091 billet, ranging from approximately 1.4 at the billet centre to 1.92 at the billet periphery. These macrosegregation patterns were explained in terms of inverse segregation in which solute rich liquid from the billet centre is sucked back through the primary Al-rich network to feed solidification shrinkage at the billet periphery. This effect was suggested to be exacerbated by centrifugal effects from the billet rotation. \nAs sprayed the billet porosity is typically 1–2% with a region of higher porosity in the splat-quenched region adjacent to the substrate. The very top of the billet often shows increased porosity because the top is rapidly chilled by the atomising gas which continues to chill the billet for 10–60 seconds after spraying. There has also been little progress in understanding and quantifying the underlying physics that controls as-sprayed porosity.\nIn most cases, the higher porosity at the billet base and top are scalped and recycled. Ultrasonic inspection is sometimes used to determine the depth of the chill zone regions to prevent unnecessary wastage. Depending on the alloy system and the final application, the remaining bulk material is usually processed to close porosity and subjected to a range of thermo-mechanical treatments. Spray formed materials are rarely used in the as-sprayed condition and are often treated by HIPing to remove porosity. In some cases, the residual atomising gas in pores may react with alloying elements to form allegedly beneficial phases e.g. N2 reacting with titanium in nickel superalloy Rene 80 to form a dispersion of TiN.\nReferences.\nThe above text is substantially taken from 'Spray forming of Si-Al alloys for thermal management applications' By Dr Al Lambourne, D.Phil Thesis, 2007, Queens College. This document is publicly held in the Oxford University Library and is available as an online resource via Oxford Research Archives (ORA). To link to this thesis follow :.", "Engineering,_Manufacturing": 1.0000010729, "qwen": "Yes"}
{"id": "73990765", "revid": "39747830", "url": "https://en.wikipedia.org/wiki?curid=73990765", "title": "Lada Saint Petersburg", "text": " \nLada Saint Petersburg is a Russian car manufacturing company owned by AvtoVAZ and headquartered in Saint Petersburg. The company was established in 2006 as a Nissan subsidiary focused on crossover assembly with the name Nissan Manufacturing Rus and started production in 2009. In 2022, it was acquired by NAMI which sold it to AvtoVAZ. The company adopted its present name in June 2023. \nHistory.\nIn 2006, Nissan began building an assembly facility with capacity to produce up to 50,000 vehicles per year at the village of Pargolovo in Saint Petersburg, incorporating it as Nissan Manufacturing Rus LLC  in June 2006. The facility became operational in June 2009 and it produced various crossovers as the X-Trail, Murano and Qashqai. By 2014, it was expanded to produce up to 100,000 vehicles per year. \nIn March 2022, following a lack of components as a result of sanctions derived from the 2022 Russian invasion of Ukraine, Nissan Manufacturing Rus halted operations. In November 2022, the state enterprise NAMI acquired Nissan Manufacturing Rus (including its assembly plant, a research and development facility, and the Moscow marketing and sales offices) for a \"symbolic price\" with a six-year buyback option for Nissan. In February 2023, NAMI sold 99% of the company in turn to its AvtoVAZ subsidiary for . AvtoVAZ announced plans to use the Nissan Manufacturing Rus plant to assemble C and D-segment vehicle kits from other manufacturers, under the Lada badging. In June 2023, the company was officially re-registered as Lada Saint Petersburg LLC. That same month, Lada Saint Petersburg announced its first model, the Lada X-Cross 5 crossover, a badge engineered Bestune T77 from FAW.", "Engineering,_Manufacturing": 1.0000058413, "qwen": "Yes"}
{"id": "54911688", "revid": "16416757", "url": "https://en.wikipedia.org/wiki?curid=54911688", "title": "Friction extrusion", "text": "Friction extrusion is a thermo-mechanical process that can be used to form fully consolidated wire, rods, tubes, or other non-circular metal shapes directly from a variety of precursor charges including metal powder, flake, machining waste (chips or swarf) or solid billet. The process imparts unique, and potentially, highly desirable microstructures to the resulting products. Friction extrusion was invented at The Welding Institute in the UK and patented in 1991. It was originally intended primarily as a method for production of homogeneous microstructures and particle distributions in metal matrix composite materials.\nDescription of the Process and Essential Process Variables.\nAs in conventional extrusion processes, in friction extrusion, a shape change is enforced on the charge by forcing its passage through a die. However, friction extrusion differs from conventional extrusion in several key ways. Critically, in the friction extrusion process, the extrusion charge (billet or other precursor) rotates relative to the extrusion die. In addition, similar to conventional extrusion, an extrusion force is applied so as to push the charge against the die. In practice either the die or the charge may rotate or they may be counter-rotating. The relative rotary motion between the charge and the die has several significant effects on the process. First, the relative motion in the plane of rotation leads to large shear stresses, hence, plastic deformation in the layer of charge in contact with and near the die. This plastic deformation is dissipated by recovery and recrystallization processes leading to substantial heating of the deforming charge. Because of the deformation heating, friction extrusion does not generally require preheating of the charge by auxiliary means potentially resulting in a more energy efficient process. Second, the substantial level of plastic deformation in the region of relative rotary motion can promote solid state welding of powders or other finely divided precursors, such as flakes and chips, effectively consolidating the charge (friction consolidation) prior to extrusion. Scrolled features on the face of the die aid material flow into the extrusion orifice which can lead to order of magnitude reduction in extrusion force compared to conventional extrusions of equivalent cross section. Third, the combined effects of elevated temperature and large levels of deformation normally lead the extrudate to have a relatively fine, equiaxed, grain structure which results from recrystallization after the conclusion of deformation: desirable crystallographic textures may also be created by the process and formation of nanocomposite structures are also possible. Based on the foregoing, it can be said that the essential controlled parameters in friction extrusion are typically:\nThe corresponding response parameters include:\nFriction Extrusion Equipment.\nIn principle, friction extrusion can be performed on any machine which can produce the required rotary and linear motions between the die and charge. Examples include machines built for friction stir welding, milling machines modified to accommodate the extrusion forces, and purpose built friction extrusion equipment such as the shear assisted processing and extrusion (ShAPE™) machine at the Pacific Northwest National Laboratory. Figures 1-3 show examples of friction extrusion equipment and extruded products. Figure 4 shows typical friction extrusion dies designed for production of wire, rod and tube. Dies are rotated in the direction which enhances material flow toward the extrusion orifice during the process.\nStrain in Friction Extrusion.\nIn conventional extrusion, the strain imparted to the charge is loosely defined by the extrusion ratio. The extrusion ratio is simply the cross-sectional area of the extrusion billet, A0, divided by the cross sectional area of the extrudate, Af. The extrusion strain is then e=ln(A0/Af).\nIn friction extrusion there is an additional strain component which will arise from the shearing motion of the rotating die as it contacts the charge. The strain produced by the rotation of the die results in redundant work as it does not accomplish a shape change. In order to investigate the strain due to shearing, studies have been performed with marker materials embedded in the material to be extruded. After extrusion, these materials are detected by metallographic methods and provide insight regarding the way in which material flows during the extrusion process. Figure 5 shows an example of how the amount of shear strain changes with changing ratios of extrusion rate to die rotation rate. In the limit of very high extrusion rates, the friction extrusion process closely mimics the conventional extrusion process with respect to strain levels.\nTypical microstructure resulting from friction extrusion.\nFigure 6 shows the cross section and microstructure of a titanium wire produced by friction extrusion of Ti-6-4 powder. Notably, the cross section is fully consolidated and the transformed b microstructure indicates that extrusion likely occurred near 1000 °C (above the beta transus for the alloy). Figure 7 shows grain size and crystallographic orientation typical of thin walled tubing extruded from AZ91 melt spun flake. Grains are refined to less than 5 mm and orientation of the (0001) planes are off-normal due to the rotational shear component. Figure 8 shows examples of friction extruded magnesium alloy tubes. Friction consolidation has also been used to refine grain size and preferentially orient texture in functional materials such as bismuth-telluride thermoelectrics and iron-silicon magnets. Examples of the effect of friction extrusion of microstructure have been reported for AZ31, various aluminum alloys and pure copper.", "Engineering,_Manufacturing": 0.9999976158, "qwen": "Yes"}
{"id": "24889742", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=24889742", "title": "Superplastic forming and diffusion bonding", "text": "Superplastic forming and diffusion bonding (SPF/DB) is a technique allowing the manufacture of complex-shaped hollow metallic parts. It combines Superplastic forming (SPF) with a second element \"Diffusion Bonding\" to create the completed structures.\nPrinciple.\nTwo metal sheets are welded together at their edges, then heated within the confines of a female mould tool.\nWhen the part is hot, an inert gas is injected between the two sheets ; the part becomes hollow to the form of the mould. Parts may be welded in other areas than the edges to give an internal structure as the sheets are blown.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "6622091", "revid": "57939", "url": "https://en.wikipedia.org/wiki?curid=6622091", "title": "OPEX (corporation)", "text": "OPEX Corporation is a manufacturing company based in Moorestown, New Jersey. They primarily manufacture warehouse automation equipment, high volume mailroom automation equipment, document scanners, and remittance processors. Their warehouse automation products have been implemented at retail and e-commerce companies such as: HBC, BOXED, and iHERB\nOPEX employs approximately ~1600 people throughout the world with locations in Moorestown Township, New Jersey USA, Plano, Texas, Bolton, England, Villebon Sur Yvette, France, and Wiesbaden, Germany.", "Engineering,_Manufacturing": 0.9999870062, "qwen": "Yes"}
{"id": "18584082", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=18584082", "title": "Abbe error", "text": "Abbe error, named after Ernst Abbe, also called sine error, describes the magnification of angular error over distance. For example, when one measures a point that is 1 meter away at 45 degrees, an angular error of 1 degree corresponds to a positional error of over 1.745 cm, equivalent to a distance-measurement error of 1.745%.\nIn machine design, some components are particularly sensitive to angular errors. For example, slight deviations from parallelism of the spindle axis of a lathe to the tool motion along the bed of the machine can lead to relatively large (undesired) taper along the part (i.e. a non-cylindrical part). Vernier calipers are not free from abbe error, while screw gauges are free from abbe error. Abbe error is the product of the abbe offset and the sine of angular error in the system.\nAbbe error can be detrimental to dead reckoning.\nFormula: \nformula_2 the error.\nformula_3 the distance.\nformula_4 the angle.", "Engineering,_Manufacturing": 0.9994732738, "qwen": "Yes"}
{"id": "17017346", "revid": "1122941299", "url": "https://en.wikipedia.org/wiki?curid=17017346", "title": "Tube drawing", "text": "Tube drawing is a process to size a tube by shrinking a large diameter tube into a smaller one, by drawing the tube through a die. This process produces high-quality tubing with precise dimensions, good surface finish, and the added strength of cold working. For this reason this process is established for many materials, mainly metalworking but also glass. Because it is so versatile, tube drawing is suitable for both large- and small-scale production. The large-scale production of glass typically uses a one step process where glass is directly drawn into a tube from a melting tank.\nThere are five types of tube drawing: tube sinking, mandrel drawing, stationary mandrel, moving mandrel, and floating mandrel. A mandrel is used in many of the types to prevent buckling or wrinkling in the workpiece.\nProcesses.\nTube sinking.\nTube sinking, also known as \"free tube drawing\", reduces the diameter of the tube without a mandrel inside the tube. The inner diameter is determined by the inner and outer diameter of the stock tube, the outer diameter of the final product, the length of the die landing, the amount of back tension, and the friction between the tube and the die. This type of drawing operation is the most economical, especially on thick-walled tubes and tubes smaller than in diameter, but does not give the best surface finish. As the tube thickness increases the surface finish quality decreases. This process is often used for the tubing on low-cost lawn furniture.\nRod drawing.\nRod drawing is the process that draws the tube with a mandrel inside the tube; the mandrel is drawn with the tube. The advantage to this process is that the mandrel defines the inner diameter and the surface finish and has a quick setup time for short runs. The disadvantages are that lengths are limited by the length of the mandrel, usually no more than , and that a second operation is required to remove the mandrel, called \"reeling\". This type of process is usually used on heavy walled or small (inner diameter) tubes. Common applications include super-high pressure tubing and hydraulic tubing (with the addition of a finishing tube sinking operation). This process is also used for precision manufacturing of trombone handslides.\nFixed plug drawing.\nFixed plug drawing, also known as stationary mandrel drawing, uses a mandrel at the end of the die to shape the inner diameter of the tube. This process is slow and the area reductions are limited, but it gives the best inner surface finish of any of the processes. This is the oldest tube drawing method.\nFloating plug drawing.\nFloating plug drawing, also known as floating mandrel drawing, uses a mandrel that is not anchored whatsoever to shape the inner diameter of the tube. The mandrel is held in by the friction forces between the mandrel and the tube. This axial force is given by friction and pressure. The greatest advantage of this is that it can be used on extremely long lengths, sometimes up to . The disadvantage is it requires a precise design otherwise it will give inadequate results. This process is often used for oil-well tubing.\nTethered plug drawing.\nTethered plug drawing, also known as semi-floating mandrel drawing, is a mix between floating plug drawing and fixed plug drawing. The mandrel is allowed to float, but is still anchored via a tether. This process gives similar results to the floating plug process, except that it is designed for straight tubes. It gives a better inner surface finish than rod drawing.", "Engineering,_Manufacturing": 0.9999871254, "qwen": "Yes"}
{"id": "17027763", "revid": "1163522062", "url": "https://en.wikipedia.org/wiki?curid=17027763", "title": "Vibratory finishing", "text": "Vibratory finishing is a type of mass finishing manufacturing process used to deburr, radius, descale, burnish, clean, and brighten a large number of relatively small workpieces.\nIn this batch-type operation, specially shaped pellets of media and the workpieces are placed into the tub of a vibratory tumbler. The tub of the vibratory tumbler and all of its contents are then vibrated. The vibratory action causes the media to rub against the workpieces which yield the desired result. Depending on the application this can be either a dry or wet process.\nUnlike rotary tumbling this process can finish internal features, such as holes. It is also quicker and quieter. The process is performed in an open tub so the operator can easily observe if the required finish has been obtained.\nVibratory tumblers.\nVibratory tumblers have an action that is similar to filing. An eccentric, rotating weight shakes the tub in a circular path, during which the entire load is lifted up at an angle and then dropped. As the load is falling (but not actually airborne) the tub returns to an upward position, applying an upward and angular force that causes a shearing action where the parts and media rub against each other.\nVibratory finishing systems tend to produce a smooth finish because the media essentially laps the parts. Since the load is moving as a unit, fragile parts are safe in the vibrator. There is no tearing action or unequal forces that tend to bend and distort parts. The larger the parts or media are, the faster the cutting action.\nThe frequency and amplitude of the machine controls the finish of the parts. The frequencies can vary from 900 to 3600 cycles per minute (CPM) and the amplitude can vary from 0 to . High frequencies, 1800 CPM or greater, and small amplitudes are used for fine finishes or delicate parts, whereas large amplitudes are used for heavier cutting. High frequencies and amplitudes can roll burrs and peen edges. The circulation of parts is best at higher frequencies, therefore, heavy pieces are run at these high frequencies with moderate amplitudes of .\nDespite the apparent rubbing action of particles against parts, studies show that the primary mechanism of material removal in vibratory finishing is erosion caused by the relatively normal impacts of particles on parts. These impacts occur at the same frequency as the vibration, and at impact velocities of less than 1 m/s.\nMedia.\nAny material or substance which is used to give finish or final touch to any part or product is classified as media. Typical media are performed in a rigid molded shape containing a bonding agent. These media work by continual exposure to abrasive particles, as the adhering agent, wears out during the usage of material.\nAll the tumbling media have some basic functions in common. These are able to provide some support to parts preventing them from mechanical damage, keep parts separate, supply abrasive, improve tumbling action, deburr and also serve as a carrier for the compound.\nThe 9 Benefit of Tumbling Media", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "17030573", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=17030573", "title": "Cold sizing", "text": "Cold sizing is a squeezing operation performed at temperatures significantly below the melting point to finish the surface of a workpiece to ensure better dimensional accuracy and surface finish.\nThe sizing operation is a squeezing operation that minimizes the thickness of the metal. Sizing is performed in an open die and only the surface where the die and workpiece touch will be sized. Many ferrous metal castings are sized to sharpen corners and flatten holes around piercings. Sizing pressure is determined by area to be sized, the metal used, and the change in metal thickness from the operation. Sizing is usually performed on semi-finished parts or parts that require an accurate finish. Stop blocks are used to ensure close tolerances.\nCold sizing, like all other cold forming processes, has a hot process counterpart. In addition to semi-finished parts, cold forming may be used on metal stock, sheet, bar, and rod stock. Cold sizing can be performed on various metals, both ferrous and non-ferrous, and even materials like polymers and plastics. Sizing is related to other squeezing operations like swaging, coining, hobbing, staking and riveting, thread rolling, and extruding.\nAlthough the whole workpiece may be inserted into the die, the sizing operation can give dimensional accuracy to a portion of the part based on the contact with the die. Sizing is mostly used to give a forged or cast part better dimensional accuracy. Mated surfaces between touching parts like gears are often sized. The sizing operation also provides a better surface hardness and finish to the workpiece. Also, the sized surface of the workpiece gets denser and stronger when the operation is performed. The dimensional tolerance of the operation is about . Primary pressing or a compacting die are typically used when sizing small batches of compact. To keep costs down, larger batches of compact usually have a specialized die made specifically for the operation.\nTroubleshooting.\nThis process is designed to achieve the desired dimensional tolerances of the forged parts. Elastic die deflection has been a problem in this operation so two solutions were developed. One solution is to make corrections in the die based on the elastic die deflection. It can be determined how much the workpiece distorted from the desired shape using a finite element analysis (FEA). This analysis is the basis the corrections are made on. The other solution is to apply a counter pressure by inserting an elastomer ring into the lower die in order to compensate the elastic die deflection.", "Engineering,_Manufacturing": 1.0000059605, "qwen": "Yes"}
{"id": "17033109", "revid": "5524899", "url": "https://en.wikipedia.org/wiki?curid=17033109", "title": "Embossing (manufacturing)", "text": "Sheet metal embossing is a stamping process for producing raised or sunken designs or relief in sheet metal. This process can be made by means of matched male and female roller dies, or by passing sheet or a strip of metal between rolls of the desired pattern. It is often combined with foil stamping to create a shiny, 3D effect.\nProcess.\nThe metal sheet embossing operation is commonly accomplished with a combination of heat and pressure on the sheet metal, depending on what type of embossing is required. Theoretically, with any of these procedures, the metal thickness is changed in its composition.\nMetal sheet is drawn through the male and female roller dies, producing a pattern or design on the metal sheet. Depending on the roller dies used, different patterns can be produced on the metal sheet. The pressure and a combination of heat actually \"irons\" while raising the level of the image higher than the substrate to make it smooth. The term \"impressing\" refers to an image \"lowered\" into the surface of a material, in distinction to an image \"raised\" out of the surface of a material.\nIn most of the pressure embossing operation machines, the upper roll blocks are stationary, while the bottom roll blocks are movable. The pressure with which the bottom roll is raised is referred to as the tonnage capacity.\nEmbossing machines are generally sized to give of strip clearance on each side of an engraved embossing roll. Many embossing machines are custom-manufactured, so there are no industry-standard widths. It is not uncommon to find embossing machines in operation producing patterns less than wide all the way up to machines producing patterns wide or more.\nCharacteristics.\nThe metal embossing manufacturing process has these characteristics:\nCommonly used materials.\nThe following materials are suitable for embossing:", "Engineering,_Manufacturing": 0.9999752045, "qwen": "Yes"}
{"id": "17038413", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=17038413", "title": "Roll slitting", "text": "Roll slitting is a shearing operation that cuts a large roll of material into narrower rolls. There are two types of slitting: log slitting and rewind slitting. In log slitting the roll of material is treated as a whole (the 'log') and one or more slices are taken from it without an unrolling/re-reeling process. In rewind slitting the web is unwound and run through the machine, passing through knives or lasers, before being rewound on one or more shafts to form narrower rolls. The multiple narrower strips of material may be known as \"mults\" (short for multiple) or \"pancakes\" if their diameter is much more than their width. For rewind slitting the machine used is called a slitter rewinder, a slitter or a slitting machine – these names are used interchangeably for the same machines. For particularly narrow and thin products, the pancakes become unstable, and then the rewind may be onto a bobbin-wound reel: the rewind bobbins are much wider than the slit width and the web oscillates across the reel as it is rewound. Apart from the stability benefit it is also then possible to put very long lengths, (frequently many tens of kilometres), onto one bobbin.\nProcess.\nSoft materials.\nSeveral methods are available for soft materials like plastic films, textiles, adhesive tapes, and paper. Razor blades, straight, or circular blades are being used. Some blades cut through the material while others crush the material against a hard roll. Those are similar to knives. The cutting blades can be set to a desired width. Some machines have many blades and can produce a number of output rolls at once. The slit material is rewound on paper, plastic or metal cores on the exit side of the machine.\nThe process is used because of its low cost and high precision for mass production. Some machines have a program that monitors the blades and sharpens the blades often to maintain the quality and precision of the cut. Depending on the industry and the product that is being slit these machine can run between 10m/min (special metal webs) and 5000 m/min (paper making process). The machines can also incorporate extensive automation to precisely control material tension, automatically position the slitting knives, automatically align the cores onto which the material is wound and to reduce manual handling of the rolls.\nExamples of materials that can be cut this way are: adhesive tape, foam, rubber, paper products, foil, plastics (such as tarps and cling wrap), glass cloth, fabrics, release liner and film.\nHard materials.\nFor harder materials, such as sheet metal, blades cannot be used. Instead, a modified form of shearing is used. Two cylindrical rolls with matching ribs and grooves are used to cut a large roll into multiple narrower rolls. This continuous production process is economical yet precise; usually more precise than most other cutting processes. However, the occurrence of rough edges known as burrs is commonplace on slit edges. Also, the geometry of these rolls is determined by specific tolerances in addition to the type of material and workpiece thickness.\nMachinery.\nFor metal coils, the slitter consists of three main parts: an uncoiler, slitter, and recoiler. The material is fed from the uncoiler, through the nip between the two circular cutting wheels (one on top and another underneath), and then re-wound in slit pieces on the recoiler.\nWhen the term \"slitter rewinder\" or \"slitting machine\" is used to describe the machine, the three parts are referred to as the unwind, the slitting section and the rewind. Slitter rewinders are normally used to slit plastic films, paper and metal foils. The unwind stage holds the roll stably and allows it to spin; it is either braked or driven to maintain accurate tension in the material. Some machines have a driven unwind which reduces the effect of inertia when starting to unwind heavy rolls or when the material is very tension-sensitive.\nThe slitting section has four main options:\nThe rewind section also has options. The main type is centre winding using differential rewind shafts. These shafts are becoming universal on most slitting machines. The differential shafts ensure an even tension across the full width of the material. Closed-loop control of the winding tension using feedback from load cells provides the total tension-control system required for running tension-sensitive materials. Precise and accurate tension control is the key to good roll slitting. Modern machines use AC vector drives with closed-loop feedback from AC motors. When used with the correct control algorithms, they produce excellent results with the minimum of maintenance.\nIndustry usage.\nRoll slitting is a technique heavily used by Converters (industry). The converter industry normally refers to companies who print, coat and laminate materials. A typical converter is a company that produces flexible packaging material for packaging food. This may involve purchasing large rolls of plastic film such as biaxially orientated polypropylene (BOPP) which is then printed to the customer's design and coated with cold seal adhesive for use on high speed packaging machines. This material is printed and coated in wide, large diameter rolls for maximum efficiency. The rolls are then slit, using a slitting machine, into smaller rolls of the size to be used on the packaging machine.", "Engineering,_Manufacturing": 1.0000078678, "qwen": "Yes"}
{"id": "17038800", "revid": "6163802", "url": "https://en.wikipedia.org/wiki?curid=17038800", "title": "Percussion welding", "text": "Percussion welding (PEW) is a type of resistance welding that blends dissimilar metals together. Percussion welding creates a high temperature arc that is formed from a short quick electrical discharge. Immediately following the electrical discharge, pressure is applied which forges the materials together. This type of joining brings the materials together in a percussive manner.\nPercussion welding is similar to flash welding and upset welding but is generally considered to be more complex because it uses an electric discharge at the joint, followed by pressure being applied to join the materials together. Percussion welding is used to join dissimilar metals together, or used when flash is not required at the joint. Percussion welding is used on materials that have small cross sectional areas.\nAdvantages of using percussion welding types include a shallow heat affected zone, and the time cycle involved is very short. Typical times can be found to be less than 16 milliseconds.", "Engineering,_Manufacturing": 0.9885588288, "qwen": "Yes"}
{"id": "24759431", "revid": "14365232", "url": "https://en.wikipedia.org/wiki?curid=24759431", "title": "Haldyn Glass", "text": "Haldyn Glass Limited (HGL) is a listed company at Bombay Stock Exchange in India (BSE: 515147) (ISIN Code 506D01012) manufacturing clear glass containers. Promoted by Haldyn Corporation Limited having its manufacturing plant in Vadodara, Gujarat while its administrative office is located in Goregaon East, Mumbai. Haldyn Glass Limited (HGL) was incorporated in the year 1991. N.D. Shetty is the Chairman and Mr. Tarun N. Shetty is Managing Director of the company.\nThe manufacturing plant of HGL is located at Village Gavasad, Taluka Padra, District Vadodara, in the state of Gujarat. Currently has total melting capacity of 360 tons per day with 8 I.S. machines which gives us leverage over the competition in manufacturing a very wide range of containers from 90 ml to 1000 ml. The I.S. machines are capable of producing 2 million high quality containers every day.Value-addition is also facilitated through the decoration facilities, consisting of modern multi-colour printing machines.\nThe Company specializes in Soda Lime Flint glass containers catering to wide range of national & international customers, across the liquor, food & beverage and cosmetic industries.\nIn 2015, Haldyn Glass Ltd entered into Joint Venture (JV) with Heinz Glas International GMBH, Germany, for the manufacturing of perfume and cosmetic glass bottles for the export and local market. The joint venture company established is Haldyn Heinz Fine Glass Pvt. Ltd", "Engineering,_Manufacturing": 0.9999808073, "qwen": "Yes"}
{"id": "24763385", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=24763385", "title": "Hot plate welding", "text": "Hot plate welding, also called heated tool welding, is a thermal welding technique for joining thermoplastics. A heated tool is placed against or near the two surfaces to be joined in order to melt them. Then, the heat source is removed, and the surfaces are brought together under pressure. Hot plate welding has relatively long cycle times, ranging from 10 seconds to minutes, compared to vibration or ultrasonic welding. However, its simplicity and ability to produce strong joints in almost all thermoplastics make it widely used in mass production and for large structures, like large-diameter plastic pipes. Different inspection techniques are implemented in order to identify various discontinuities or cracks.\nHistory.\nHot plate welding was first used in the early 1930s for joining PVC. \nIt gained in popularity with the prevalence of polyolefins, which are difficult to adhesively bond.\nBy the 1960s, it was among the most widely used plastic welding methods.\nHot plate welding was used for pipelines and appliances as well as injection moldings. Numerous national and international associations for welding have specifications and guidelines for hot plate welding, including the Deutscher Verband fuer Schweissen (DVS) in Germany, the American Welding Society (AWS) in the United States, and the Comité Européen de Normalisation (CEN) in Europe.\nProcess.\nConventional hot plate welding.\nThe hot plate welding process can be divided into four phases: matching, heating, change-over, and welding/forging.\nThe matching phase serves to match the geometry of the weld surfaces to the theoretical welding plane. The weld surfaces are heated through conduction by physical contact with the hot plate. The hot plate temperature range is above the melting temperature of the material, and a constant pressure between 0.2 and 0.5 MPa is applied against the hot plate. This causes the weld surfaces to conform to the hot plate, which has the desired weld geometry. This also removes surface irregularities that would increase thermal contact resistance. After the parts are in full contact with the hot plate, the heating phase starts and pressure is reduced to a minimum.\nDuring the heating phase, the weld region is heated conductively until melted, without substantial displacement of the material. Pressure is maintained either at a minimum to keep the parts and the hot plate in contact or at zero with a preset displacement. The melt surface reaches approximately below the temperature of the hot plate. The viscosity of the melted material can be controlled through the temperature of the hot plate and the heating time. The surface of hot plate is often coated with PTFE to stop the molten plastic from sticking, which limits the hot plate temperature to .\nThe temperature of the parts during this phase can be modeled by assuming a constant temperature boundary condition and using the one-dimensional heat equation:\nwhere \"θ\" is the temperature, \"x\" is the position, \"t\" is the time, \"θi\" is the initial temperature, \"θs\" is the constant surface temperature, \"κ\" is the thermal diffusivity, and erfc is the complementary error function. This model is valid for most cases, since the thermal contact resistance is low and the thermal mass of the hot tool is large compared to the plastic parts. For more precise predictions of the heat flow, the thermal contact resistance and the temperature dependence of the thermal properties of the plastic also need to be considered.\nAfter sufficient heating time, the change-over phase begins. During this phase, the parts are retracted from the hot plate, the plate is quickly moved away, and the parts are brought together. The change-over should be as short as possible, because the melted region cools off during this time.\nThe welding/forging phase begins when the two molten surfaces are pressed together. This creates intermolecular diffusion of the plastic molecules according to reptation theory. Weld strength is provided by entanglement of the diffused plastic molecules. The necessary welding pressure depends on the melt viscosity and wall thickness of the parts and usually ranges between 0.025 and 0.05 MPa. This pressure is maintained while the melted material cools and resolidifies. During this, some plasticized material in the weld zone is squeezed out, forming flash. Mechanical stops may be used to limit the amount of squeezed out material in order to prevent a cold weld.\nVariants.\nCommon variants of conventional hot plate welding include high-temperature and non-contact versions. Both of these variants help with the problem of material sticking to the hot plate between weld cycles; the stuck material can degrade and transfer to subsequent welds, resulting in poor quality and aesthetically unappealing welds.\nWith high-temperature hot plate welding, an uncoated hot plate is heated to between , as the PTFE coating degrades at high temperatures. The high temperature decreases the viscosity of the melt, so it can peel off from the hot plate when removing the parts. This can be accompanied during the change-over phase by rapid movement of the parts from the hot plate; this prevents stringing of the melted plastic due to its viscoelastic properties. Any residual material on the hot plate's surface is usually either oxidized away or mechanically removed. With some thermoplastics, the residual material cannot be easily removed and accumulates over time. The hot plates may need to be removed and cleaned between cycles. With the higher temperatures, the matching and heating phases are shortened from those of conventional hot plate welding. However, reduced weld strength from thermal degradation of the plastic can still occur, though most of the degraded material is forced out by the flow of melted material. High-temperature hot plate welding is known to perform well for:\nWith non-contact hot plate welding, the weld surfaces are melted without physical contact with the hot plate through convection and radiation heating. The hot plate temperature is between , and the weld surfaces are placed about from the hot plate. Heat input needs to be controlled to prevent thermal degradation while plasticizing the material. This variant has no matching phase, so part fit must be good prior to welding, with part deviation not exceeding . In practice, non-contact hot plate welding is only used for small parts whose dimensions do not exceed . An additional consideration is the stack effect when the hot plate is oriented vertically, which can cause uneven heating of the weld surfaces.\nAnother variant is hot wedge or hot shoe welding for joining thin sheets with lap seams. A heated wedge travels between the two sheets and melts the weld surfaces while wedge rollers apply light pressure to force intimate contact; drive rollers apply pressure at the tip of the wedge where the sheets converge to form a continuous seam.\nHot wedge welding can produce either single or dual seam joints. For dual seam joints, a split wedge that is unheated in the middle is used. This leaves an unwelded air pocket between the seams that can be pressurized to nondestructively test the joint integrity. With hot wedge welding, the speed of travel is an added parameter as the wedge unit is self-propelled by the rollers. The typical temperature range when welding high-density polyethylene (HDPE) is ; the travel speed is typically .\nParameters.\nParameters used in hot plate welding are the hot plate temperature, the pressure (or displacement) during matching, the pressure during heating, the pressure and displacement during the weld phase, and the times for matching, heating, change-over and cooling. These parameters have an interdependent effect on the weld quality and cannot be set individually.\nThe hot plate temperature is taken at the surface of the plate. It is set based on the hot plate welding variant along with the properties of the material, including melting temperature, melt viscosity, and thermal degradation limits. Conventional hot plate welding uses temperatures above the melting temperature. The high-temperature variant uses temperatures above the material's degradation temperature, about above the melting point. The non-contact variant uses temperatures above the melting point. With non-contact welding, the radiation heating depends not only on the temperature but also on the emissivity of the hot plate material.\nThe pressure during the matching phase removes warpage of the weld surfaces to ensure full contact with the hot plate without causing the parts to deform. During the heating phase, a minimum pressure is maintained to keep the parts in contact with the hot plate, as a larger pressure would squeeze out material. The welding pressure brings the molten weld surfaces into intimate contact and squeezes out entrapped air. Too high a pressure would squeeze out most of the hot material from the joint, leaving cooler material to form a cold weld. Too low a pressure limits intermolecular diffusion and produces a weak weld. A mechanical stop may be used in the welding phase to limit the amount of material squeeze out by varying the welding pressure.\nThe matching and heating times control the amount of heat input during those phases. The matching time is set so that surface irregularities are melted and removed. The heating time determines the melt layer thickness. Too thick a melt results in excess flash and unfavorable molecular orientation at the joint interface. Too thin a melt produces a brittle weld. The change-over time determines the temperature of the melted material as welding begins and, therefore, should be as short as possible to minimize surface cooling. Typical change-over times are around 2 to 3 seconds, even for large parts. Cooling time refers to the time until the joined parts have solidified (when the molten material has cooled below its melting temperature) and can be removed from the machine. The welded part should not be stressed until it has further cooled until room temperature.\nEquipment.\nHot plate welding equipment consists of two main components, a clamping fixture and one or multiple hot plates. The primary function of the fixture is to provide support during the welding process to prevent deformation under welding pressure. Conventional machines have fixtures that fully conform to the parts being welded and allow for flexibility in production by accepting different fixture configurations. Custom machines may be configured to weld a specific component and do not provide as much flexibility as standard machines.\nHot plates are generally designed for specific working temperatures. Hot plates for conventional hot plate welding have a working temperature of at least and are made from aluminum alloys. The hot plates may also be coated in Polytetrafluoroethylene (PTFE) to prevent sticking of the polymer to the hot plate. Caution should be taken as the PTFE coatings degrade over time and sets of interchangeable fixtures should be available during continuous operation. Hot plates for high-temperature hot plate welding have a maximum working temperature of and are made from aluminum bronze alloys. Due to the lower thermal conductivity of these alloys precaution must be taken to ensure that there is uniform heating along the hot plate surface. PTFE has a maximum working temperature of therefore, non-stick coatings cannot be used for this type of operation. Lastly, hot plates for non-contact hot plate welding are used for temperatures up to are made from either aluminum bronze or stainless steels.\nHot plate welding machines are generally operated by pneumatic, hydraulic or electromechanical controls. Machines can be configured to perform welds with the faying surface in either the horizontal or vertical position. Longer components such as pipes are more commonly welded in the horizontal position whereas moldings with internal fittings such as a starter battery are welded in the vertical position. A proportional-integral-derivative (PID)  controller also assists in maintaining desired temperatures during each process.\nJoint Types.\nWhile there are various joint configurations, a butt joint in which the two joining materials are aligned along the same plane is one of the most common joint designs for thermoplastics. There are various modifications of this joint that are implemented for different applications which include the following listed below.\nMaterial weldability.\nHot plate welding can be used for joining all thermoplastics and thermoplastic elastomers whose melting temperature range lies below their decomposition temperature. Since only the plastic itself can be joined, additives, used to improve material properties or reduce cost, can reduce weldability. Additives can also reduce weld strength by acting as stress concentrators. Examples of additives include stabilizers, lubricants, processing aids, coloring agents, reinforcing materials (talcum, glass fibers, carbon fibers, etc.).\nThe water content of the plastic also affects weldability. This affects thermoplastics that absorb water from the surrounding air, mainly amorphous thermoplastics. High water content can lead to the formation of bubbles during heating and joining, reducing weld strength. Therefore, parts should be welded shortly after injection molding, stored in a dry environment, or welded with adjusted parameters.\nHot plate welding can be used to join some combinations of dissimilar thermoplastics. Typically, semi-crystalline plastics are only compatible with semi-crystalline plastics, and amorphous plastics are only compatible with amorphous plastics. If the plastics have the same melting point and melt viscosity, conventional or high-temperature hot plate welding can be used. With different melting points or different viscosities, dual hot plates should be used, with each hot plate set to a different temperature. Common thermoplastic combinations include:\nApplications.\nHot plate welding is used for joining parts ranging from a few centimeters up to 1.6 meters. It is also used for making continuous welds in lining membranes. Its usage can be divided into two main categories, namely production applications and pipe welding. These differ in their equipment and joint designs.\nProduction applications.\nOne major industry using hot plate welding is the automotive sector. Tail light housings made of ABS are joined with lenses made of either PMMA or PC using a modified butt joint. ABS and PMMA have similar melting temperatures and can be welded using a single hot plate, while ABS and PC requires dual hot plates due to PC's higher melting temperature. Vacuum suction cups are used to move the parts to prevent scuffing. Both conventional and high-temperature variants are used. A typical cycle time is 60 seconds with a hot plate temperature of 370 °C.\nFuel tanks made of blow-molded HDPE need as many as 34 parts welded to it, including clips, filler necks, vent lines, Heat shield boss plug, Gas vent value/Roll over Valves, Breather Nipple and brackets. The parts are welded individually using groove butt joints. Each component needs a different matching time, and cycle times are less than a minute per component.\nThe cases and lids of automotive batteries are made of thin PP copolymers, which have low melt viscosity. High-temperature hot plate welding is used on butt joints with flash covers. A typical machine can weld two batteries in a time of less than 30 seconds.\nOther automotive components welded by hot plate are carburetor floats, coolant and washer fluid reservoirs, and ventilation ducts. Non-automotive items include dishwasher spray arms, laundry detergent boxes, steam iron reservoirs, HDPE barrels, PP transport pallets, medical needle disposal boxes, and PVC window frames.\nPipe welding.\nHot plate welding, referred to as fusion welding in many industries, is commonly used to join plastic pipes. These pipes, as opposed to steel ones, are less likely to rupture during an earthquake. Pipe welding uses special joint configurations, namely butt, socket and saddle/sidewall, each with its own welding procedures.\nButt fusion welding has similar process phases as conventional hot plate welding. Before welding, the pipe ends are faced and the profiles are rounded and aligned with each other. The remaining phases proceed as normal, though sometimes the matching phase can be skipped. When welding dissimilar plastics, in lieu of dual hot plates, the pipe with the lower melt flow index can be heated earlier than the other, such that both pipe ends have the same melt viscosity at the end of the heating phase. After cooling, the flash bead is sometimes removed to leave smooth surfaces on the interior and exterior. Problems with the weld can be determined by inspecting this bead.\nSocket fusion welding uses male and female heating tools attached to a hot plate to heat the exterior of the pipe and the interior of the socket simultaneously. This is typically used for pipes ranging from 40 to 125 millimeters. With this joint, the welding pressure is supplied by the interference fit of the pipe and socket, so these parts as well as the heating tools need to be within tolerance.\nSaddle/sidewall fusion welding is used for joining saddle fittings onto the sidewall of a pipe to create branches. The exterior of the pipe and the matching surface of the saddle fitting are heated using concave and convex heating tools. The saddle fusion machine applies welding force through the centerline of the pipe. Prior to welding, the exterior of the pipe needs to be cleaned of all contaminants, because the melt layer of the pipe is not displaced from the joint.\nNon-destructive Testing (NDT).\nThere are two methods of testing including non-destructive and destructive testing. While the quality of a weld can only be determined through destructive means, NDT allows for the determination of defects in the welded region. The following section will highlight some of the non-destructive methods used in welding of thermoplastics.\nVisual inspection.\nVisual inspection testing can only be used to detect flaws on the surface of the weld but is the least expensive method of NDT. This method of inspection may be performed both during and post welding. During welding the operator is inspecting for discoloration, misalignment, notches and other surface discontinuities. Post welding inspection allows the operator to inspect for microstructural features which may be detrimental to the welded part.\nX-ray testing.\nX-ray testing is a costly method of inspection; therefore, it is generally limited to pressure vessels and pipelines carrying hazardous materials. This method is most effective when the densities of the imperfection and the plastic have a substantial difference and is used for detection of voids, inclusions and other imperfections. A disadvantage to this method is that microstructural defects cannot be determined through this method of testing.\nLeak-tightness test.\nThis method of testing is most often used for welded pipes and other closed containers. There are different variations of this test which are dependent on the type of medium (water, air, gas) used to pressurize the sample. It is common to conduct this test in vacuum conditions.\nHigh-voltage test.\nHigh voltage testing known as “spark test” is an alternative to the leak-tightness test. This test in performed by coating the weld with an electrically conductive substance such as a wire, fibers or coils. When a voltage is applied an arc will form, showing the presence of a leak. This test is not well suited for polar thermoplastics such as PVC as they will generate heat leading to potential degradation of the weld.\nUltrasonic testing.\nUltrasonic testing uses high frequency waves that travel through the welded regions. These waves are able to detect defects based on the different densities between the imperfection and plastic part. There are two primary methods of conducting ultrasonic testing and that is by using a transmitter and receiver in conjunction or by using an ultrasonic transducer. These conventional methods similar to X-ray testing are not able to detect microstructural changes in the weld. Advanced ultrasonic testing such as phased array ultrasonics (PAUT) is currently being developed for inspection of hot plate and electrofusion joints.\nPolyethylene (PE) pipes are desirable over other materials such as metals for the transportation of fluids due to their resistance to corrosion leading longer lifespans. They are however, limited from being used in nuclear power plants due unreliable NDT methods. Current methods involve using practices that do not provide a complete analysis of a welded PE pipe.\nUsing a butt joint configuration produces a small fusion zone and inspection is further complicated due to the high attenuation of PE. Proper probe placement is also limited during inspection due to interference with the weld bead. The PAUT system has five primary components. These components are the phased array probe, probe wedge, probe holder, scanner and flaw detector. A minimum of four phased array probes are required for the ultrasonic signal to detect a flaw. The membrane water wedge transmits the ultrasound from the probes into the pipe while minimizing energy loss and the probe holder ensures proper contact between the wedge and pipe. The scanning system made specifically for this testing method carries the probe around the joint of the pipe during inspection. Lastly, the flaw detector analyzes the signal from the probe. This method is specifically designed for  inspection of electrofusion and butt fusion welds of various sized pipes ranging from a thickness of 8-65mm and a diameter of 90-800mm. PAUT is well suited for the detection of:\nTwo ISO reports are under development and being reviewed by technical committee (TC) 138 (Plastic pipes, fittings and valves for the transport of fluids) to include PAUT as a method of volumetric NDT of PE pipes. A procedure has also been made for UT of butt fusion joints including but not limited to HDPE and medium-density polyethylene (MDPE). The ISO and ASME standards are listed as:", "Engineering,_Manufacturing": 1.0000060797, "qwen": "Yes"}
{"id": "24771554", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=24771554", "title": "Final assembly schedule", "text": "Final Assembly Schedule, often abbreviated as FAS and sometimes referred to as finishing schedule, is a schedule of end items to finish the product for specific customer orders in a make to order (MTO) or assemble-to-order (ATO) environment.\nOverview.\nFinishing schedule may involve assembly but also final mixing, cutting, packaging etc. The FAS is prepared after receipt of customer order. FAS schedules the operations required to complete the product from the level where it is stocked (or master-scheduled) to the end-item level.\nFinal assembly schedule (FAS) entries are needed when end products do not appear in the MPS. These end items are assembled to order or have several customer options that can be combined in various configurations. These products belong to the category of products with variants and options wherein many shippable end-item products are assembled from few standard components (in modular construction and modular design). For these products, two different schedules are required: master production schedule (MPS) for end-item components and final assembly schedules (FAS) for shippable products.\nAssembly-to-order.\nFAS controls the portion of the business from fabricated components and sub-assemblies planned on the basis of forecast to customer-ordered shippable products in ATO environments.\nMake-to-order.\nIn MTO business, it states the specific schedule for satisfying customer orders.\nMake-to-stock.\nIn make-to-stock (MTS) final assembly schedule is not needed as the MPS itself plans the end item.\nActivities included in FAS.\nThe final assembly schedule serves to plan and control final assembly and test operations. The following activities are generally included in the FAS:\na) launching of final assembly orders,\nb) picking of components parts,\nc) sub-assembly,\nd) painting or other finishing operations\ne) scheduling the fabrication or purchase of any components not under MPS control but \nneeded in final assembly\nf) packing\nProduct characteristics.\nThe final assembly schedule is usually used for products that \na) have relatively low volume\nb) are highly customized\nc) have short producrement or manufacturing lead-time\nReferences.\nKhalid Sheikh (2003) 'Manufacturing resource planning (MRP II): with introduction to ERP, SCM and CRM'. New York: McGraw-Hill Companies. ", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "2313018", "revid": "44560121", "url": "https://en.wikipedia.org/wiki?curid=2313018", "title": "Lead (electronics)", "text": "In electronics, a lead  is an electrical connection consisting of a length of wire or a metal pad (surface-mount technology) that is designed to connect two locations electrically. Leads are used for many purposes, including: transfer of power; testing of an electrical circuit to see if it is working, using a test light or a multimeter; transmitting information, as when the leads from an electrocardiograph are attached to a person's body to transmit information about their heart rhythm; and sometimes to act as a heatsink. The tiny leads coming off through-hole electronic components are also often called \"pins\"; in ball grid array packages, they are in form of small spheres, and are therefore called \"balls\".\nMany electrical components such as capacitors, resistors, and inductors have only two leads, while some integrated circuits can have several hundred or even more than a thousand for the largest ball grid array packages. Integrated circuit pins often either bend under the package body like a letter \"J\" (J-lead) or come out, down, and form a flat foot for securing to the board (S-lead or gull-lead). \nMost kinds of integrated circuit packaging are made by placing a silicon chip on a lead frame, wire bonding the chip to the metal leads of the lead frame, and covering the chip with plastic. The metal leads protruding from the plastic are then either \"cut long\" and bent to form through-hole pins, or \"cut short\" and bent to form surface-mount leads. Such lead frames are used for surface mount packages with leads – such as Small Outline Integrated Circuit Quad Flat Package  – and for through-hole packages such as dual in-line package  – and even for so-called \"leadless\" or \"nolead\" packages – such as Quad Flat Noleads package.\nThe lead frame (and therefore the pins, if any, formed from that lead frame) are occasionally made from Invar or similar alloys, due to their low coefficient of thermal expansion.\nElectrical effects.\nFor many circuit designs it can be assumed that the leads do not contribute to the electrical effects of individual components. However, this assumption begins to break down at higher frequencies and at very small scales. These effects come from the physical construction of the leads. The leads are often metal connections that run from the rest of the circuit to the materials that each component is made of. This design results in a very small capacitance between the ends of the leads where they connect to the device and very small inductances and resistances along each lead. Because the impedance of each component is a function of the frequency of the signals being passed through the device and the inductance and capacitance of the device the leads can cause substantial variation in the properties of components in radio frequency circuits.", "Engineering,_Manufacturing": 0.9993360043, "qwen": "Yes"}
{"id": "5360186", "revid": "1130206589", "url": "https://en.wikipedia.org/wiki?curid=5360186", "title": "Twin-carbon arc welding", "text": "Unlike single-carbon arc welding, in twin-carbon arc welding (TCAW) the arc is maintained between two carbon (graphite) electrodes held in a special holder. The Ac current was usually used. It was switched on by operating bringing two electrodes closer by a mechanism which also adjusted arc length. The two electrodes touch momentarily, then separate and thus an arc is established. TCAW is unshielded and no artificial pressure is applied.\nHistory.\nTCAW was first proposed in 1874.\nUse.\nThe size of the arc depends upon the distance between the electrode tips, electrode diameters and the welding current. The heat input to the job can be varied by changing the arc size or the distance between the arc and workpiece. After striking the arc, welding can be carried out in the same way as in TIG welding process.\nAn AC supply is recommended for TCAW. In case a DC supply is used, the positive electrode will disintegrate and consume at a much faster rate as compared to negative electrode, because two-thirds of the total heat is generated at the positive anode. This will produce an unstable arc and require frequent adjustment of the electrodes. In AC welding, because of alternate reversals of polarity, both the electrodes will be affected equally and present no problem.\nThe electrodes employed for TCAW are approximately of the same diameter as the workpiece thickness. The magnitude of arc current required for welding depends upon both electrode diameter and plate thickness. For example, an 8 mm diameter electrode will need about 65 amps to weld a mild steel sheet of thickness 3.5 mm and 80 Amps to weld a sheet of 6 mm thickness.\nTCAW, though more complex than single carbon arc welding, possesses the advantage that arc is independent of the job and can be moved anywhere without getting extinguished. Moreover, the workpiece is not a part of the electrical circuit.\nWhile carbon electrodes have been replaced by tungsten and other alternatives in many places, in developing countries simple twin carbon-arc torches are a cheaper and more sustainable alternative to oxyacetylene torches. A simple version of a TCAW apparatus was designed in Ethiopia, it has reduced costs and improved the accessibility of welding services. ", "Engineering,_Manufacturing": 0.9996943474, "qwen": "Yes"}
{"id": "2821366", "revid": "1160582352", "url": "https://en.wikipedia.org/wiki?curid=2821366", "title": "Servomotor", "text": "A servomotor (or servo motor) is a rotary actuator or linear actuator that allows for precise control of angular or linear position, velocity, and acceleration. It consists of a suitable motor coupled to a sensor for position feedback. It also requires a relatively sophisticated controller, often a dedicated module designed specifically for use with servomotors.\nServomotors are not a specific class of motor, although the term \"servomotor\" is often used to refer to a motor suitable for use in a closed-loop control system.\nServomotors are used in applications such as robotics, CNC machinery, and automated manufacturing.\nMechanism.\nA servomotor is a closed-loop servomechanism that uses position feedback to control its motion and final position. The input to its control is a signal (either analog or digital) representing the position commanded for the output shaft.\nThe motor is paired with some type of position encoder to provide position and speed feedback. In the simplest case, only the position is measured. The measured position of the output is compared to the command position, the external input to the controller. If the output position differs from that required, an error signal is generated which then causes the motor to rotate in either direction, as needed to bring the output shaft to the appropriate position. As the positions approach, the error signal reduces to zero, and the motor stops.\nThe very simplest servomotors use position-only sensing via a potentiometer and bang-bang control of their motor; the motor always rotates at full speed (or is stopped). This type of servomotor is not widely used in industrial motion control, but it forms the basis of the simple and cheap servos used for radio-controlled models.\nMore sophisticated servomotors make use of an Absolute encoder (a type of rotary encoder) to calculate the shafts position and infer the speed of the output shaft. A variable-speed drive is used to control the motor speed. Both of these enhancements, usually in combination with a PID control algorithm, allow the servomotor to be brought to its commanded position more quickly and more precisely, with less overshooting.\nServomotors vs. stepper motors.\nServomotors are generally used as a high-performance alternative to the stepper motor. Stepper motors have some inherent ability to control position, as they have built-in output steps. This often allows them to be used as an open-loop position control, without any feedback encoder, as their drive signal specifies the number of steps of movement to rotate, but for this, the controller needs to 'know' the position of the stepper motor on power up. Therefore, on the first power-up, the controller will have to activate the stepper motor and turn it to a known position, e.g. until it activates an end limit switch. This can be observed when switching on an inkjet printer; the controller will move the ink jet carrier to the extreme left and right to establish the end positions. A servomotor can immediately turn to whatever angle the controller instructs it to, regardless of the initial position at power up if an absolute encoder is used.\nThe lack of feedback of a stepper motor limits its performance, as the stepper motor can only drive a load that is well within its capacity, otherwise missed steps under load may lead to positioning errors and the system may have to be restarted or recalibrated. The encoder and controller of a servomotor are an additional cost, but they optimize the performance of the overall system (for all of speed, power, and accuracy) relative to the capacity of the basic motor. With larger systems, where a powerful motor represents an increasing proportion of the system cost, servomotors have the advantage.\nThere has been increasing popularity in closed-loop stepper motors in recent years. They act like servomotors but have some differences in their software control to get smooth motion. The main benefit of a closed-loop stepper motor is its relatively low cost. There is also no need to tune the PID controller on a closed loop stepper system.\nMany applications, such as laser cutting machines, may be offered in two ranges, the low-priced range using stepper motors and the high-performance range using servomotors.\nEncoders.\nThe first servomotors were developed with synchros as their encoders. Much work was done with these systems in the development of radar and anti-aircraft artillery during World War II.\nSimple servomotors may use resistive potentiometers as their position encoder. These are only used at the very simplest and cheapest level and are in close competition with stepper motors. They suffer from wear and electrical noise in the potentiometer track. Although it would be possible to electrically differentiate their position signal to obtain a speed signal, PID controllers that can make use of such a speed signal, generally warrant a more precise encoder.\nModern servomotors use rotary encoders, either absolute or incremental. Absolute encoders can determine their position at power-on but are more complicated and expensive. Incremental encoders are simpler, cheaper, and work at faster speeds. Incremental systems, like stepper motors, often combine their inherent ability to measure intervals of rotation with a simple zero-position sensor to set their position at start-up.\nInstead of servomotors, sometimes a motor with a separate, external linear encoder is used. These motor + linear encoder systems avoid inaccuracies in the drivetrain between the motor and linear carriage, but their design is made more complicated as they are no longer a pre-packaged factory-made system.\nMotors.\nThe type of motor is not critical to a servomotor, and different types may be used. At the simplest, brushed permanent magnet DC motors are used, owing to their simplicity and low cost. Small industrial servomotors are typically electronically commutated brushless motors. For large industrial servomotors, AC induction motors are typically used, often with variable frequency drives to allow control of their speed. For ultimate performance in a compact package, brushless AC motors with permanent magnet fields are used, effectively large versions of Brushless DC electric motors.\nDrive modules for servomotors are a standard industrial component. Their design is a branch of power electronics, usually based on a three-phase MOSFET or IGBT H bridge. These standard modules accept a single direction and pulse count (rotation distance) as input. They may also include over-temperature monitoring, over-torque, and stall detection features. As the encoder type, gearhead ratio, and overall system dynamics are application specific, it is more difficult to produce the overall controller as an off-the-shelf module, and so these are often implemented as part of the main controller.\nControl.\nMost modern servomotors are designed and supplied around a dedicated controller module from the same manufacturer. Controllers may also be developed around microcontrollers in order to reduce cost for large-volume applications.\nIntegrated servomotors.\nIntegrated servomotors are designed to include the motor, driver, encoder, and associated electronics into a single package.", "Engineering,_Manufacturing": 0.9999842644, "qwen": "Yes"}
{"id": "8868532", "revid": "46016783", "url": "https://en.wikipedia.org/wiki?curid=8868532", "title": "Machinery repairman", "text": "Machinery repairman (abbreviated as MR) is a United States Navy occupational rating. The Shop Machinist and the Outside Machinist ratings of the Machinist's Mate rating were combined to create the Machinery Repairman rating in 1948.\nMachinery repairmen perform organizational and intermediate maintenance on assigned equipment and in support of other ships, requiring the skillful use of lathes, milling machines, boring mills, grinders, power hack saws, drill presses, and other machine tools; portable machinery; hand tools; and measuring instruments found in a machine shop. \nMachinery repairmen are skilled machine tool operators. They make replacement parts for a ship's engine auxiliary equipment, such as evaporators, air compressors and pumps. The repair of deck equipment, including winches and hoists, condensers and heat exchange devices are completed by machinist mates. Machinery repairmen assist enginemen by repairing or producing parts in the machine shop. Shipboard machinery repairmen do not frequently operate main propulsion machinery, primarily performing machine shop duties.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "8572631", "revid": "1102944920", "url": "https://en.wikipedia.org/wiki?curid=8572631", "title": "Jarden Zinc Products", "text": "Jarden Zinc Products LLC. has been manufacturing continuous casting zinc strip since the late 1800s. The company is a subsidiary of One Rock Capital. The company is most notable for being the sole manufacturer of planchets used in the production of the United States penny. Jarden Zinc is also the manufacturer of the ZincSecure based Ukrainian ₴5 and ₴10 coins.\nProducts.\nThe company's largest source of revenue comes from the production of coin blanks, having produced over 300 billion blanks at their Tennessee facility. The company also supplies zinc strips used in various cathodic protection, building, automotive, architectural, and specialty products. Such products include zinc galvanic anodes, LifeJacket, and LifeDowel automotive blade fuses, metal flashing, guttering systems, plumbing hardware, wall cladding, braille, organ pipes, counter tops, signs, and medals among other niche items.\nProduct development.\nZinc's attributes and characteristics can be manipulated to create new zinc alloys. Jarden Zinc Products has a product development team that is tasked with creating new alloys that meet specific market needs.", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "47522537", "revid": "31070190", "url": "https://en.wikipedia.org/wiki?curid=47522537", "title": "GlobeCore", "text": "GlobeCore is a manufacturer and vendor of industrial equipment for production of bitumen emulsions, modified bitumen, oil regeneration and oil purification, fuel blending, biodiesel production, wet milling and nonoblending. Its headquarters are in Oldenburg, Germany.\nAbout company.\nGlobeCore’s spectrum of services ranges from metal cutting to assembling of processing units. GlobeCore has facilities in several countries, including the United States, the UAE, and South Africa. Technical assistance to customers is provided by 17 dealer agencies worldwide.\nProducts.\nThe following is a list of processing units manufactured by GlobeCore:\nServices.\nThe company maintains, repairs and updates its own equipment and provides training for the customer's service staff.\nCustomers.\nGlobeCore serves the following companies and industries:", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "41825676", "revid": "23914831", "url": "https://en.wikipedia.org/wiki?curid=41825676", "title": "Selective heat sintering", "text": "Selective heat sintering (SHS) is a type of additive manufacturing process. It works by using a thermal printhead to apply heat to layers of powdered thermoplastic. When a layer is finished, the powder bed moves down, and an automated roller adds a new layer of material which is sintered to form the next cross-section of the model. SHS is best for manufacturing inexpensive prototypes for concept evaluation, fit/form and functional testing. SHS is a Plastics additive manufacturing technique similar to selective laser sintering (SLS), the main difference being that SHS employs a less intense thermal printhead instead of a laser, thereby making it a cheaper solution, and able to be scaled down to desktop sizes.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "52631154", "revid": "32990417", "url": "https://en.wikipedia.org/wiki?curid=52631154", "title": "Multiple lining tool", "text": "The multiple lining tool is a burin chisel used in engraving with multiple cutting blades for making parallel lines to create a hatching effect.\nThe multiple lining tool is also called the multiple tool, lining tool, multiliner, liner, shooter, multiple graver, comb, and half-tone comb.\nDescription.\nThe multiple lining tool allows the engraver to create hatched shading effects by engraving multiple parallel lines at the same time. It achieves this by having two or more cutting blades, which are available in different grades or sizes, such as the density of lines. The resulting hatching has a mechanical look.", "Engineering,_Manufacturing": 0.9967169166, "qwen": "Yes"}
{"id": "52635266", "revid": "44780537", "url": "https://en.wikipedia.org/wiki?curid=52635266", "title": "Adrian Hobbs", "text": "Charles Adrian Hobbs (born January 1946, in Ilkley, West Yorkshire, UK) specialises in vehicle crashworthiness with a background in accident and injury investigation/analysis.\nAs an engineer and later as Honorary Chief Research Scientist, Hobbs was involved in the UK Government’s programme of Crash Injury Research for nearly 30 years. He undertook the research that helped lead to the mandatory wearing of the seat belt in the UK, the development of the Offset Deformable Frontal Barrier Crash Test and the establishment of the safety organisation Euro NCAP. Hobbs was awarded a C.B.E. in 2008.\nHobbs has provided advice to the World Bank (1), the World Health Organization, the European Commission and Central European and North African countries on transport safety and the provision of emergency services (2-4).\nSafety career.\nHobbs joined the Transport Research Laboratory (TRL) in 1972 as a Scientific Officer. For two years he was involved in researching accident causation, investigating accidents alongside the police about the contributing factors to an accident. (5,6) In 1976 he reported on his analysis of brake defects and their contribution to accidents (7).\nIn 1974, he shifted his focus to car occupant injuries. He analysed and reported on the direct connection between the accident, resulting injuries, their causes and the effectiveness of safety features with medical data, car inspection and questionnaires. During this period he concluded that intrusion into the passenger compartment of the vehicle during a frontal impact accident played a very major role in causing injuries. (8-10)\nAs a result of this research, he realised how effective wearing a seat belt was in preventing serious injury to a vehicle’s occupant. In 1978, Adrian published a comprehensive study of the life-saving potential of seat belt wearing.(11-14) This study helped lead to the passing of the mandatory seat belt wearing legislation in the UK (Hansard), which came into force on 31 January 1983. (15)\nHobbs then switched his research focus to vehicle safety and, in 1985, he designed a demonstration Pedestrian Safety Car (based on a Mini Metro). (16-21), later modified to incorporate current thinking in Frontal and Side impact protection. (22,23) For side impact, conventional wisdom held that protection came from strengthening the side of the car and providing padding protection on the inside of the door. Hobbs expressed his concern that many manufacturers were simply fitting door beams, located where they could increase the risk of injury. (24-31) Hobbs's modifications did improve the car, but the car still did not provide good protection or meet the proposed side impact test requirements. Elsewhere in France, Germany, and the UK another vehicle was tested. Hobbs researched about this car, which although much weaker than the modified Metro, performed better. He discovered that a lighter door rather than a heavier door bounces off the impacting car and starts moving the occupant earlier, increasing the time the body has to absorb the impact, so reducing the severity of injuries. He also discovered that when the door is controlled to move in vertically, it spreads the load over the chest, abdomen and pelvis consequently avoiding its concentration on the vulnerable chest area, reducing the possibility of a fatal injury. The provision of padding, Hobbs also concluded, had to be very soft to help spread the load and cushion the impact. (32-35) These conclusions and research directly contributed to the development of the European Side Impact Directive.\nIn the early 1990s, Hobbs identified the inadequacies in the current frontal crash test procedure and his research led to the development of the Offset Deformable Barrier (ODB) Frontal Impact Crash Test. (36-52). Hobbs's frontal ODB test was adopted, in Europe and elsewhere, for both legislation and consumer test programmes.\nWith this research under his belt, Hobbs took on the study of Compatibility, the science of how cars could work together to minimise injuries to the occupants of both vehicles. (53-57) Although the research identified what needed to be changed and an assessment procedure was developed, research funding dried up and government interest in further improving car crash safety was absent.\nEurope.\nDuring the 1990s, Hobbs was an active member of the European Experimental Vehicles Committee (EEVC) in particular of the Frontal Impact and the Compatibility Working Groups, which he initiated. He also collaborated with other working groups to develop test procedures for side impact and pedestrian protection.\nHobbs was asked by the European Transport Safety Council (ETSC) to present the case for the adoption of the EEVC Frontal and Side Impact test procedures for European Type Approval to the European Parliament in Strasbourg. The EEVC was proposing an initial crash test speed of 56 km/h (approx. 30 mph) rather than the 60 km/h already used in research crash tests. The intention was that the test speed would later be increased to 60 km/h. This was at a European Parliament Inter-group meeting, with Max Mosley of the Federation Internationale de L’Automobile (FIA) as chairman. Industry was there to oppose – their concern was that cars could not be built to withstand the speeds proposed. Yet Max Mosley, profoundly moved by the recent death of Ayrton Senna on the race track, developed an increased interest in reducing the road accident injury toll. The death of a racing driver had spurred on the cause to improve car safety for the public and to prevent millions of deaths on European roads.\nA new consumer information programme.\nMeanwhile, back in the UK Hobbs had been working on a proposal for an independent crash test programme called UK NCAP. His proposal, presented in 1994, outlined to the UK department of Transport the concept of a consumer information programme based on the EEVC proposed frontal impact, side impact and pedestrian protection crash test procedures. His reason for a consumer-based information car-testing programme was clear. He cited the New Car Assessment Programme in the US that had had a more significant effect on changing car design than any US legislative test. He also cited the magazine Auto Motor und Sport and the ADAC, in Germany, whose published car crash tests results were already influencing how manufacturers designed their cars, as they endeavoured to obtain good ratings in the published tests.\nThe Department of Transport agreed to go ahead with the proposal and initiated the first phase of tests and assessments. (58-60) Following further discussions with the European Commission, in Brussels, (61,62) Hobbs mentioned the proposal to Max Mosley. Mosley was inspired to help and make Hobbs’s wish for a Europe wide consumer test programme a reality. Called initially the UK NCAP programme it later came to be branded, with the support of the FIA and other European players, as Euro NCAP.\nEURO NCAP.\nEuro NCAP (the European New Car Assessment Programme) is now an established consumer-testing programme that assesses and publishes the safety of new cars and provides valuable safety information to consumers. Thousands of crash-tested cars later and the award of thousands of stars to industry, Euro NCAP has led to the establishment of other similar consumer programmes across the world and has contributed greatly to the safety of cars available on the European market.\nYet it all began with Hobbs’s persistence and a group of dedicated safety pioneers. The inaugural meeting of Euro NCAP was held in December 1996 with only a few members: the UK Department of Transport, the FIA, the Swedish National Road Association (SNRA) and International Testing. The very first results of 7 crash-tested super-minis were released publicly to the media in early 1997, much to the consternation of industry. (63-67)\nHobbs was the first Chairman of the Technical Working Group and he later became Secretary General until his retirement in 2007.\nEuro NCAP’s team of engineers and labs now carry out a frontal, side impact and pedestrian protection test as well as assessments on child protection and on the range of technologies existing within the car. Tests are carried out on all vehicles from super-minis to SUVs to the latest hybrids and petrol engines, resulting in a star rating with a maximum award of 5 stars. Special awards are also given to car makers with innovative technologies.\nSafety achievements and developments in the industry, as a direct result of the work of Euro NCAP, have included the following:\nFor frontal impact protection: improved car structures limiting passenger compartment intrusion, so providing space for the restraints to operate without the occupants impacting the car’s interior, improved seat belts with pre-tensioners and load limiters, improved multi-stage frontal airbags, removal of hazards in the knee impact area and knee protecting air bags.\nFor side impact protection: improved car side structures with airbags to protect the head, chest, abdomen and pelvis, and pole impact protection.\nAdditional achievements have been: car fronts with improved pedestrian protection, improved child occupant protection, provision of effective reminders to wear seat belts, promotion and greater introduction of technologies such as electronic stability controls, autonomous emergency braking and lane departure warnings.\nPersonal life.\nHobbs continues to provide consultancy on road and vehicle safety issues and provides advice to the media. He is a motor sport enthusiast having been a rally driver in his youth. Since retirement, he has become involved in supporting a number of local and national organisations. Since 1974, he has been married to Jacqueline, a retired teacher with a keen focus on special needs. Their adopted son Philip died in 2002, aged 28. Adrian and Jackie live together in Berkshire.\nReferences.\nOther selected publications", "Engineering,_Manufacturing": 0.9894501567, "qwen": "Yes"}
{"id": "58548553", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=58548553", "title": "2018 Niger Cup", "text": "The 2018 Coupe nationale du Niger is the 43rd edition of the Coupe nationale du Niger, the knockout football competition of Niger.\nRound 1.\n[May 20]\nEntente FC (Dosso) lt Akokana FC d' Arlit (Agadez)\n[May 22]\nRepresentant de Zinder lt AS Université AM (Niamey)\nAS Garde Nationale (Niamey) 5-0 Wombeye FC (Maradi)\nAS Forces Armées Nigériennes (Niamey) lt US Gendarmerie Nationale (Niamey)\n[May 23]\nSoniantcha FC (Tillabery) lt Dan Gourmou (Tahoua)\nJangorzo FC (Maradi) 8-1 Espoir FC (Zinder)\nOlympic FC (Niamey) 1-1 AS Douanes (Niamey) [3-4 pen]\nUrana FC d' Arlit (Agadez) bt Arewa FC de Doutchi (Dosso)\nAS Forage (Niamey) 1-4 Racing FC (Niamey)\nAzzura FC (Zinder) 0-3 Sahel Sporting Club (Niamey)\n[May 24]\nAtlantique (Maradi) 0-3 ASN NIGELEC (Niamey)\nAS ZAM (Niamey) bt AS Tsunami FTC (Niamey)\nNational Dendi (Dosso) 0-7 JS Tahoua\n[May 25]\nNassara de Tessaoua (Maradi) 0-8 Nassara AC (Agadez)\n[Jun 6]\nLantarki (Agadez) lt AS SONIDEP (Niamey)\nBarka FC (Diffa) lt AS Police (Niamey)\nRound 2.\n[Jun 10]\nUS Gendarmerie Nationale (Niamey) 0-1 Racing FC (Niamey)\n[Jun 12]\nAS Douanes (Niamey) 0-0 AS Police (Niamey) [4-5 pen]\nAS SONIDEP (Niamey) 2-1 AS ZAM (Niamey)\n[Jun 13]\nUrana FC d' Arlit (Agadez) drw AS Université AM (Niamey) [AS Université on pen]\nNassara AC (Agadez) 1-3 Jangorzo FC (Maradi)\n[Jun 16]\nJS Tahoua 0-1 Sahel Sporting Club (Niamey)\nASN NIGELEC (Niamey) 2-1 Dan Gourmou (Tahoua)\n[Jun 17]\nAS Garde Nationale (Niamey) 2-1 Akokana FC d' Arlit (Agadez)\nQuarterfinals.\n[Jul 7]\nAS Garde Nationale (Niamey) 2-1 AS SONIDEP (Niamey)\n[Jul 8]\nAS Université AM (Niamey) 0-2 Racing FC (Niamey)\nSahel Sporting Club (Niamey) 1-3 Jangorzo FC (Maradi)\n[Jul 10]\nASN NIGELEC (Niamey) drw AS Police (Niamey) [5-3 pen]\nSemifinals.\nFirst leg\n[Jul 15]\nJangorzo FC (Maradi) 2-3 Racing FC (Niamey)\n[Jul 19]\nASN NIGELEC (Niamey) 0-1 AS Garde Nationale (Niamey)\nSecond leg\n[Jul 22]\nAS Garde Nationale (Niamey) 2-0 ASN NIGELEC (Niamey) [3-0 agg]\n[Jul 26]\nRacing FC (Niamey) 2-1 Jangorzo FC (Maradi) [5-3 agg]\nFinal.\n[Aug 3, Stade Régional, Maradi]\nAS Garde Nationale (Niamey) 0-0 Racing FC (Niamey) [5-4 pen]", "Engineering,_Manufacturing": 0.9995068312, "qwen": "Yes"}
{"id": "58563544", "revid": "19531195", "url": "https://en.wikipedia.org/wiki?curid=58563544", "title": "Fan-out wafer-level packaging", "text": "Fan-out wafer-level packaging (also known as wafer-level fan-out packaging, fan-out WLP, FOWL packaging, FO-WLP, FOWLP, etc.) is an integrated circuit packaging technology, and an enhancement of standard wafer-level packaging (WLP) solutions.\nIn conventional technologies, a wafer is diced first, and then individual dies are packaged; package size is usually considerably larger than the die size. By contrast, in standard WLP flows integrated circuits are packaged while still part of the wafer, and the wafer (with outer layers of packaging already attached) is diced afterwards; the resulting package is practically of the same size as the die itself. However, the advantage of having a small package comes with a downside of limiting the number of external contacts that can be accommodated in the limited package footprint; this may become a significant limitation when complex semiconductor devices requiring a large number of contacts are considered.\nFan-out WLP was developed to relax that limitation. It provides a smaller package footprint along with improved thermal and electrical performance compared to conventional packages, and allows having higher number of contacts without increasing the die size.\nIn contrast to standard WLP flows, in fan-out WLP the wafer is diced first. But then the dies are very precisely re-positioned on a carrier wafer or panel, with space for fan-out kept around each die. The carrier is then reconstituted by molding, followed by making a redistribution layer atop the entire molded area (both atop the chip and atop the adjacent fan-out area), and then forming solder balls on top.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "17459765", "revid": "1138772381", "url": "https://en.wikipedia.org/wiki?curid=17459765", "title": "Honing (metalworking)", "text": "Honing is an abrasive machining process that produces a precision surface on a metal workpiece by scrubbing an abrasive grinding stone or grinding wheel against it along a controlled path. Honing is primarily used to improve the geometric form of a surface, but can also improve the surface finish.\nTypical applications are the finishing of cylinders for internal combustion engines, air bearing spindles and gears. There are many types of hones, but all consist of one or more abrasive stones that are held under pressure against the surface they are working on.\nOther similar processes are lapping and superfinishing.\nHoning stones.\nHoning uses a special tool, called a \"honing stone\" or a \"hone\", to achieve a precision surface. The hone is composed of abrasive grains that are bound together with an adhesive. Generally, honing grains are irregularly shaped and about 10 to 50 micrometers in diameter (300 to 1500 mesh grit). Smaller grain sizes produce a smoother surface on the workpiece.\nA honing stone is similar to a grinding wheel in many ways, but honing stones are usually more friable, so that they conform to the shape of the workpiece as they wear in. To counteract their friability, honing stones may be treated with wax or sulfur to improve life; wax is usually preferred for environmental reasons.\nAny abrasive material may be used to create a honing stone, but the most commonly used are corundum, silicon carbide, cubic boron nitride, and diamond. The choice of abrasive material is usually driven by the characteristics of the workpiece material. In most cases, corundum or silicon carbide are acceptable, but extremely hard workpiece materials must be honed using superabrasives.\nThe hone is usually turned in the bore while being moved in and out. Special cutting fluids are used to give a smooth cutting action and to remove the material that has been abraded. Machines can be portable, simple manual machines, or fully automatic with gauging depending on the application.\nModern advances in abrasives have made it possible to remove much larger amount of material than was previously possible. This has displaced grinding in many applications where \"through machining\" is possible. External hones perform the same function on shafts.\nProcess mechanics.\nSince honing stones look similar to grinding wheels, it is tempting to think of honing as a form of low-stock removal grinding. Instead, it is better to think of it as a self-truing grinding process.\nIn grinding, the wheel follows a simple path. For example, in plunge grinding a shaft, the wheel moves in towards the axis of the part, grinds it, and then moves back out. Since each slice of the wheel repeatedly contacts the same slice of the workpiece, any inaccuracies in the geometric shape of the grinding wheel will be transferred onto the part. Therefore, the accuracy of the finished workpiece geometry is limited to the accuracy of the truing dresser. The accuracy becomes even worse as the grind wheel wears, so truing must occur periodically to reshape it.\nThe limitation on geometric accuracy is overcome in honing because the honing stone follows a complex path. In bore honing, for example, the stone moves along two paths simultaneously. The stones are pressed radially outward to enlarge the hole while they simultaneously oscillate axially. Due to the oscillation, each slice of the honing stones touch a large area of the workpiece. Therefore, imperfections in the honing stone's profile cannot transfer to the bore. Instead, both the bore and the honing stones conform to the average shape of the honing stones' motion, which in the case of bore honing is a cylinder. This averaging effect occurs in all honing processes; both the workpiece and stones erode until they conform to the average shape of the stones' cutting surface. Since the honing stones tend to erode towards a desired geometric shape, there is no need to true them. As a result of the averaging effect, the accuracy of a honed component often exceeds the accuracy of the machine tool that created it.\nThe path of the stone is not the only difference between grinding and honing machines, they also differ in the stiffness of their construction. Honing machines are much more compliant than grinders. The purpose of grinding is to achieve a tight size tolerance. To do this, the grinding wheel must be moved to an exact position relative to the workpiece. Therefore, a grinding machine must be very stiff and its axes must move with very high precision.\nA honing machine is relatively inaccurate and imperfect. Instead of relying on the accuracy of the machine tool, it relies on the averaging effect between the stone and the workpiece. Compliance is a requirement of a honing machine that is necessary for the averaging effect to occur. This leads to an obvious difference between the two machines: in a grinder the stone is rigidly attached to a slide, while in honing the stone is actuated with pneumatic or hydraulic pressure.\nHigh-precision workpieces are usually ground and then honed. Grinding determines the size, and honing improves the shape.\nThe difference between honing and grinding is not always the same. Some grinders have complex movements and are self-truing, and some honing machines are equipped with in-process gauging for size control. Many through-feed grinding operations rely on the same averaging effect as honing.\nEconomics.\nSince honing is a high-precision process, it is also relatively expensive. Therefore, it is only used in components that demand the highest level of precision. It is typically the last manufacturing operation before the part is shipped to a customer. The dimensional size of the object is established by preceding operations, the last of which is usually grinding. Then the part is honed to improve a form characteristic such as surface finish, roundness, flatness, cylindricity, or sphericity.\nPerformance advantages of honed surfaces.\nSince honing is a relatively expensive manufacturing process, it can only be economically justified for applications that require very good form accuracy. The improved shape after honing may result in a quieter running or higher-precision component.\nThe flexible honing tool provides a relatively inexpensive honing process.\nThis tool produces a controlled surface condition unobtainable by any other method. It involves finish, geometry and metallurgical structure. A high-percentage plateau free of cut, torn and folded metal is produced. The flexible hone is a resilient, flexible honing tool with a soft cutting action. The abrasive globules each have independent suspension that assures the tool to be self-centering, self-aligning to the bore, and self-compensating for wear.\nCross-hatch finish.\nA \"cross-hatch\" pattern is used to retain oil or grease to ensure proper lubrication and ring seal of pistons in cylinders. A smooth glazed cylinder wall can cause piston ring and cylinder scuffing. The \"cross-hatch\" pattern is used on brake rotors and flywheels.\nPlateau finish.\nThe plateau finish is one characterised by the removal of \"peaks\" in the metal while leaving the cross-hatch intact for oil retention. The plateaued finish increases the bearing area of the finish and does not require the piston or ring to \"break in\" the cylinder walls.\nPlateau honing specification:\nA profilometer provides modern, defined descriptions of cylinder bore finish that include “RPK” (Reduced Peak Height), “RVK” (Reduced Valley Depth) and “RK” (Core Roughness Depth), which is based on both the “RPK” and “RVK” measurements.", "Engineering,_Manufacturing": 0.9997766614, "qwen": "Yes"}
{"id": "10020856", "revid": "4626", "url": "https://en.wikipedia.org/wiki?curid=10020856", "title": "Overlay control", "text": "In silicon wafer manufacturing overlay control is the control of pattern-to-pattern alignment necessary in the manufacture of silicon wafers.\nSilicon wafers are currently manufactured in a sequence of steps, each stage placing a pattern of material on the wafer; in this way transistors, contacts, etc., all made of different materials, are laid down. In order for the final device to function correctly, these separate patterns must be aligned correctly – for example contacts, lines and transistors must all line up.\nOverlay control has always played an important role in semiconductor manufacturing, helping to monitor layer-to-layer alignment on multi-layer device structures. Misalignment of any kind can cause short circuits and connection failures, which in turn impact fab yield and profit margins.\nOverlay control has become even more critical now because the combination of increasing pattern density and innovative techniques such as double patterning and 193 nm immersion lithography creates a novel set of pattern-based yield challenges at the 45 nm technology node and below. This combination causes error budgets to shrink below 30 percent of design rules, where existing overlay metrology solutions cannot meet total measurement uncertainty (TMU) requirements.\nOverlay metrology solutions with both higher measurement accuracy/precision and process robustness are key factors when addressing increasingly tighter overlay budgets. Higher order overlay control and in-field metrology using smaller, micro-grating or other novel targets are becoming essential for successful production ramps and higher yields at 45 nm and beyond.\nExamples of the widely adopted overlay measurement tools worldwide are KLA-Tencor's ARCHER , and the nanometrics CALIPER series, overlay metrology platforms.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "10040741", "revid": "1143394835", "url": "https://en.wikipedia.org/wiki?curid=10040741", "title": "Punch (tool)", "text": "A punch is a tool used to indent or create a hole through a hard surface. They usually consist of a hard metal rod with a narrow tip at one end and a broad flat \"butt\" at the other. When used, the narrower end is pointed against a target surface and the broad end is then struck with a hammer or mallet, causing the blunt force of the blow to be transmitted down the rod body and focused more sharply onto a small area. Typically, woodworkers use a ball-peen hammer to strike a punch.\nUse.\nPunches are used to drive fasteners such as nails and dowels, making a hole, or forming an indentation/impression of the tip on a workpiece. Decorative punches may also be used to create a pattern or even form an image.\nPin.\nMetal pins and similar connectors are driven in or out of holes using a pin punch.\nFor removal, first use a starter punch to loosen the pin, then use a pin punch to finish.\nCenter.\nA \"center punch\" is used to mark the center of a point. It is usually used to mark the center of a hole when drilling holes. A drill has the tendency to \"wander\" if it does not start in a recess. A center punch forms a large enough dimple to \"guide\" the tip of the drill. The tip of a center punch has an angle between 60 and 90 degrees. When drilling larger holes, where the drill bit is wider than the indentation produced by a center punch, the drilling of a pilot hole is usually needed.\nAn automatic center punch operates without the need for a hammer.\nPrick punch.\nA \"prick punch\" is similar to a center punch but used for marking out. It has a sharper angled tip to produce a narrower and deeper indentation. The indentation can then be enlarged with a center punch for drilling. The tip of a prick punch is 60 degrees (the angle depends on what type of prick punch one is using). It is also known as a dot punch.\nTransfer.\nA \"transfer punch\" is a punch (usually in an index set) of a specific outer diameter that is non-tapered and extends the entire length of the punch (except for the tip). It is used to tightly fit the tolerances of an existing hole and, when struck, precisely \"transfer\" the center of that hole to another surface. It can be used, for example, to duplicate the hole patterns in a part, or precisely set locations for threaded holes (created by drilling and tapping) to bolt an object to a surface.\nDrift.\nA \"drift \"punch\"\" is misleadingly named; it is not used as a punch in the traditional sense of the term. A drift punch, or drift pin, or lineup punch, is used as an aid in aligning bolt or rivet holes prior to inserting a fastener. A drift punch is constructed as a tapered rod, with the hammer acting on the large end of the taper. The long end of a drift punch is placed into the semi-aligned bolt holes of two separate components, and then driven into the hole. As it is driven in, the taper forces the two components into alignment, allowing for easy insertion of the fastener. Unlike most punches, force is never (and should never be) applied to the tip, or end of a drift pin.\nRoll pins.\nRoll pin punches are used to drive roll pins. Standard pin punches should never be used on a roll pin. Because of the hollow, thin wall construction of a roll pin, a standard pin punch will often collapse, mar or distort the end of the pin or be driven into, and jammed inside, the hollow core of the roll pin. When choosing a roll pin punch, select one that is no larger than the compressed diameter of the pin. If a punch is used that is larger than the pin, the surrounding metal in which the pin is seated can be damaged. Also, a roll pin punch should not be used which is smaller than the compressed diameter of the pin. If this occurs, it may be possible to drive the punch through the hollow center of the roll pin.\nRoll pin punches are designed with a small projection in the center of the pin tip to support the circumference of the roll pin. The tips of roll pin punches are not flat and should never be used on regular solid pins. If a roll pin punch is used on a solid pin, it will mar or mark the pin.\nIf the end of a roll pin punch is damaged or deformed, it should be discarded. It is virtually impossible to regrind the tip of the roll pin punch and properly shape the center projection.\nWhen using a roll pin punch, make sure the axis of the shank of the roll pin punch is in line with the axis of the roll pin. Do not cant the roll pin punch off to one side. When you strike the roll pin punch, hit it directly on the top of its head. If you strike the head of the roll pin punch at an angle you may bend the shank.\nDecorative.\nPunches with a decorative motif have been used to create patterns or images on metals and various other materials, notably leather. In goldsmithing, bookbinding and armor-making the technique is called pointillé. In printmaking punches were used to create most of the image in the plates for printing metalcuts.\nLetter.\nAlso known as \"letter stamps\" or \"number stamps\", letter punches are used to emboss the impression of a letter or number into a workpiece. They are most common in the reverse image, this allows the end result to be immediately readable, regardless they may be made as a positive image. This is essential in the case of die or mold making and ensures that the finished product will be readable, as a die is a negative image.\nTablet press.\nThese punches are a part of tablet press. Unlike most punches, tablet press punches have a concave ending in the shape of the desired tablet. There are the lower and the upper punches to compress the powder in between.", "Engineering,_Manufacturing": 0.9999628067, "qwen": "Yes"}
{"id": "9680291", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=9680291", "title": "Laser converting", "text": "For industrial processes, Laser converting or laser digital converting is a production technology that enables device manufacturers to produce features that otherwise would be problematic or even impossible to die-cut, without the need for tooling.\nIn contrast to traditional mechanical converting, laser digital converting utilizes the features of lasers and advance software technology to convert parts in extremely high accuracy. In production environment, the laser digital converting is the economics of scale when the production run is short, as there is virtually no 'up-front' cost associated with machine tools making and storage. Also, the turnaround time is minimal as it only involves software interpretation on the imported engineering diagram of the part.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "44038529", "revid": "39374154", "url": "https://en.wikipedia.org/wiki?curid=44038529", "title": "AQSIQ-Registration for the Export of Recycling Material to China", "text": "The “Registration of Overseas Supplier of Imported Scrap Materials“ is required for Non-Chinese companies for importing industrial waste and recycling parts into China. The application has to be submitted at the AQSIQ (General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Chinese: 中华人民共和国国家质量监督检验检疫总局). The registration is mandatory for all Non-Chinese exporters. Aim of this registration is to monitor the import of potential environmental harmful material and ensure that no material is imported into China that are not in compliance with the Chinese environment standards. \nIf companies are not registered, parts will be detained in customs and no import process is possible. In addition to the registration of the exporting companies, the parts have to be registered with the CCIC (China Certification & Inspection Group; Chinese 中国检验认证集团), and, furthermore, these parts will be accordingly inspected.\nProducts requiring registration.\nThe following products require this registration", "Engineering,_Manufacturing": 1.0000039339, "qwen": "Yes"}
{"id": "6588369", "revid": "1135136294", "url": "https://en.wikipedia.org/wiki?curid=6588369", "title": "Outline of manufacturing", "text": "The following outline is provided as an overview of and topical guide to manufacturing:\nManufacturing – use of machines, tools and labor to produce goods for use or sale. Includes a range of human activity, from handicraft to high-tech, but most commonly refers to industrial production, where raw materials are transformed into finished goods on a large scale.\nHistory.\nOrigins of manufacturing.\nIndustrial Revolution\nEmergence of the factory.\nFactory\nImprovement of industrial processes.\nIndustrial process\nOperations of manufacturing.\nModern manufacturing processes.\nTaxonomy of manufacturing processes\nManufacturing process management", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "6591389", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=6591389", "title": "Mask shop", "text": "A mask shop is a factory which manufactures photomasks for use in the semiconductor industry. There are two distinct types found in the trade. Captive mask shops are in-house operations owned by the biggest semiconductor corporations, while merchant mask shops make masks for most of the industry.\nMerchant mask shops will produce photomasks for a variety of integrated device manufacturers (IDMs), foundries or optical device companies in addition to providing excess cavity work and re-pellicle for captive mask shops.\nThe company structure is similar to that of any medium-sized manufacture and has the\nfollowing unique departments or mask makers:\nPhotomask market.\nThe worldwide photomask production market was $3.1 billion in 2013. Almost half of market attributed to captive mask shops (in-house mask shops of major chipmakers).\nInfrastructure (technical and financial).\nThe costs of creating new mask shop for 180 nm processes were estimated in 2005 as $40 million, and for 130 nm - more than $100 million. In 2013 cost of new 28 nm mask shop was estimated at $110 – 140 million.\nFuture.\nAs technology shrinks, the cost to mask shops increase and the product turn around time grow longer as well. The trend in this new decade is for manufacturing to migrate eastwards to reduce cost and lead times. Once technology restrictions in the Wassenaar Arrangement are reduced, high end reticles and integrated circuits will be produced in mainland China\nrather than Taiwan.", "Engineering,_Manufacturing": 0.9990304708, "qwen": "Yes"}
{"id": "51972784", "revid": "20317270", "url": "https://en.wikipedia.org/wiki?curid=51972784", "title": "Cimier", "text": "Montres Cimier SA is an independent Swiss watch manufacturer whose headquarters is in Biel, Switzerland. Cimier produces mechanical watches as well as quartz watches.\nHistory.\nThe origin of Cimier goes back in 1924 when the mukesh watchmaker Joseph Lapanouse founded his company Lapanouse SA in Hölstein and sold his watches first under the brand Rego and later Cimier. Since the beginning, Joseph Lapanouse specialised in manufacturing pin-pallet watches, called Roskopf.\nIn the 1950s, the company, that became in the meantime Lapoanouse-Cimier SA, industrialized the first pin-pallet escapement chronograph sold at 21 million pieces during its lifetime. At the end of the 1960s the annual production reached 1.5 million pieces and the company employed over 500 people in Bubendorf.\nIn the 1970s, the watch industry experienced the quartz crisis. The number of mechanical watches sold was drastically reduced. Cimier developed and industrialized its own quartz movement. However, the number of pieces produced did not reach the threshold of profitability. As a result, in 1985, the Swiss manufacturer decided to temporarily cease production.\nIn 2003, the brand Cimier was reborn through the company which has the same name.\nIn 2010, Cimier opened the Watch Academy. The concept allowed customers to create and build their own watch in Cimier's workshop. The customer can choose between several manual movements and an automatic movement.", "Engineering,_Manufacturing": 0.6966587305, "qwen": "Yes"}
{"id": "51986887", "revid": "3560547", "url": "https://en.wikipedia.org/wiki?curid=51986887", "title": "Coil zipper", "text": "Coil zipper—also known as nylon coil zipper—is a type of zipper whose teeth/elements are made from that is traditionally nylon. The coil is sewn to a zipper tape to make the final product. The final zipper product is completed when the nylon coiled teeth are sewn onto the zipper tape. Nylon coil zippers have a continuous coil chain made from nylon. When this coil is positioned on the back of the zipper and not in the front, this kind of zipper is called invisible zipper.\nDesign.\nNylon zippers are highly flexible and are available in a wide range of sizes. The high compatibility of the coil zippers is the main attribute for their huge number of applications in fashion wear, canvas goods, and bags. These types of zippers are also the top choice for the outdoor and luggage industries. Nylon coil zippers are most commonly found in tents, suitcases, backpacks, and other camping apparels.\nThough nylon coil zippers are a popular choice for a large number of applications, the use of nylon is now being replaced with polyester. Polyester coil zippers are also becoming widespread. They are made in various gauge sizes and colors. This makes them well-suited to several use cases. \nBenefits.\nCoil zippers offer higher horizontal strength . Coil zippers are also easier to repair; an out-of-alignment tooth can be realigned simply by zipping and unzipping past it. Another advantage of nylon zippers is its two-way functionality. The sliders can be fixed in either direction of the zipper chain and they will can still function smoothly. Nylon is lightweight, heat resistant and rustproof, making nylon coil zippers durable and reliable.\nManufacturing.\nThe main elements required in the manufacturing process of coil zipper are a stringer, slider, and a tab. The stringer consists of a tape and teeth assembly. The tab is used to pull the slider up and down which opens and closes the zipper.", "Engineering,_Manufacturing": 0.9949513674, "qwen": "Yes"}
{"id": "60760613", "revid": "46253198", "url": "https://en.wikipedia.org/wiki?curid=60760613", "title": "Circular procurement", "text": "Circular procurement is an approach that recognises the role that private and public authorities can play in supporting the transition towards a circular economy. Circular procurement can be defined as the process by which private or public authorities purchase works, goods or services that seek to contribute to closed energy and material loops within supply chains whilst minimising, and in the best case avoiding, negative environmental impacts and waste creation across their whole life-cycle. As a concept, it builds on Sustainable Procurement, adding elements such as closed-loop material use.\nPolicy context.\nThe EU Action Plan for the Circular Economy has established an ambitious programme of action which will help to ‘close the loop’ of product lifecycles. This plan recognises public procurement as a key driver in the transition towards the circular economy, and it sets out several actions that the European Commission will take to facilitate the integration of circular economy principles in GPP. These include highlighting circular aspects in new or updated sets of EU GPP Criteria.\nCircular public procurement also has a role in achieving the Sustainable Development Goals, defined by the United Nations 2030 Agenda for Sustainable Development. Especially, SDG 12 - Responsible Consumption and Production – includes a specific target on promoting sustainable public procurement practices, in accordance with national policies and priorities.\nFurthermore, several countries, regions, and cities have been developing their circular strategies in which public procurement is often emphasized as a key mechanism for scaling up the transition to a circular economy.\nThree Levels of Circular Procurement.\nThere are three types or ‘levels’ of models for implementing circular procurement:\nBenefits.\nBesides sustainable procurement, circularity can help buyers take a more comprehensive approach - from the first stages of procurement to the end of product life – while achieving financial benefits. A circular economy will retain materials at their highest value, push for innovation and support local employment markets. By 2025, at a global scale, it has an estimated potential to add $1 trillion to the global economy and create 100,000 new jobs within the next five years.", "Engineering,_Manufacturing": 0.9753429294, "qwen": "Yes"}
{"id": "25471560", "revid": "35936988", "url": "https://en.wikipedia.org/wiki?curid=25471560", "title": "Joern Meissner", "text": "Joern Meissner (born c. 1970) is a German academic, business consultant, entrepreneur and Professor of Supply Chain Management & Pricing Strategy at Kühne Logistics University in Hamburg.\nBiography.\nMeissner received MA in Business Management in 1997 at the University of Hamburg, and his Ph.D. in Management Science in 2005 from the Columbia Business School under the supervision of Professors Awi Federgruen and Costis Maglaras.\nHe is a current lecturer in the Management Science Department at the Lancaster University Management School and also lectures at the University of Hamburg and the University of Manheim, and has taught at Handelshochschule Leipzig (the Leipzig Graduate School of Management).\nMeisser hold the position of Professor of Supply Chain Management & Pricing Strategy at Kuehne Logistics University in Hamburg. Prof. Meissner is active in the area of Supply Chain Management, Dynamic Pricing, and Revenue Management.\nHe is the founder of Manhattan Review, a multi-national test prep, MBA admissions consulting, and career training company.\nWork.\nMeissnerhas been published in various journals including Manufacturing and Service Operations Management (MSOM); Operations Research; Naval Research Logistics; European Journal of Operational Research, and written several book chapters.\nHe has also been featured in BusinessWeek for Manhattan Review’s Communications Bootcamp with Columbia Business School. Newsweek, The Independent, The Times, Handelsblatt and Frankfurt Allgemeine Zeitung have also quoted Prof. Meissner regarding the GMAT and MBA admissions.\nHis paper “Dynamic pricing strategies for multiproduct revenue management problem,\" jointly written with Costis Maglaras, was a finalist in the MSOM Best Paper award 2009. He frequently advises companies ranging from Fortune 500 companies to emerging start-ups on various issues related to his research.", "Engineering,_Manufacturing": 0.996235013, "qwen": "Yes"}
{"id": "25477746", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=25477746", "title": "MTConnect", "text": "MTConnect is a manufacturing technical standard to retrieve process information from numerically controlled machine tools. As explained by a member of the team that developed it, \"This standard specifies the open-source, royalty-free communications protocol based on XML and HTTP Internet technology for real-time data sharing between shopfloor equipment such as machine tools and computer systems. MTConnect provides a common vocabulary with standardized definitions for the meaning of data that machine tools generate, making the data interpretable by software applications.\" A simple, real-world example of how this tool is used to improve shop management is given by the same author.\nHistory.\nThe initiative began as a result of lectures given by David Edstrom of Sun Microsystems and David Patterson, professor of Computer Science at the University of California, Berkeley (UCB) at the 2006 annual meeting of the Association for Manufacturing Technology (AMT). The two lectures promoted an open communication standard to enable Internet connectivity to manufacturing equipment. \nInitial development was carried out by a joint effort between the UCB Electrical Engineering and Computer Sciences (EECS) department, the UCB Mechanical Engineering (ME) department (both in the College of Engineering) and the Georgia Institute of Technology, using input from industry representatives. The resulting standard is available under royalty-free licensing terms.\nDescription.\nMTConnect is a protocol designed for the exchange of data between shop floor equipment and software applications used for monitoring and data analysis. MTConnect is referred to as a read-only standard, meaning that it only defines the extraction (reading) of data from control devices, not the writing of data to a control device. Freely available, open standards are used for all aspects of MTConnect. Data from shop floor devices is presented in XML format, and is retrieved from information providers, called Agents, using Hypertext Transfer Protocol (HTTP) as the underlying transport protocol. MTConnect provides a RESTful interface, which means the interface is stateless. No session must be established to retrieve data from an MTConnect Agent, and no logon or logoff sequence is required (unless overlying security protocols are added which do). Lightweight Directory Access Protocol (LDAP) is recommended for discovery services.\nVersion 1.0 was released in December 2008.\nThe first public demonstration of MTConnect occurred at the International Manufacturing Technology Show (IMTS) held in Chicago, Illinois September 2008. There, 25 industrial equipment manufacturers networked their machinery control systems, providing process information that could be retrieved from any web-enabled client connected to the network.\nSubsequent demonstrations occurred at EMO (the European machine tool show) in Milan, Italy in October 2009, and the 2010 IMTS in Chicago.\nStandard.\nThe MTConnect standard has three sections. The first section provides information on the protocol and structure of the XML documents via XML schemas. The second section specifies the machine tool components and the description of the available data. The third and last section specifies the organization of the data streams that can be provided from a manufacturing device. The MTConnect Institute is considering adding a fourth section to support mobile assets that include tools and work-holdings.\nMTConnect took an incremental approach to defining the requirements for manufacturing device communications. It did not exhaustively define every possible piece of data an application can collect from a manufacturing device, but it works forward from business and research objectives to define the required elements to meet those needs. The standard catalogued important components and data items for metal cutting devices. MTConnect provides an extensible XML schema to allow implementors to add custom data to meet their specific needs, while providing as much commonality as possible.\nOn September 16, 2010, The MTConnect Institute and the OPC Foundation announced cooperation between the respective organizations.\nApplications.\nThe maintenance cost and losses in productivity with unplanned downtime for machine tool components such as spindle bearings and ball screws could be reduced if one could proactively take action prior to failure. In addition, cutting tools and inserts are expensive to replace when they are still in good condition, but replacing the tools too late can be costly due to scrap and re-work. The proposed health monitoring application will use MTConnect to extract controller data and pattern recognition algorithms to assess the health condition of the spindle and machine tool axes. The health assessment approach is based on running a routine program each shift in which the most recent data patterns are compared to the baseline data patterns. An online tool condition monitoring module is also proposed and uses controller data such as the spindle motor current, with other add on sensors (vibration, acoustic emission) to accurately estimate and predict tool wear. With the added transparency of the machine tool health information, one can take proactive actions before significant downtime or productivity losses occur.", "Engineering,_Manufacturing": 0.9999530315, "qwen": "Yes"}
{"id": "16929046", "revid": "1461430", "url": "https://en.wikipedia.org/wiki?curid=16929046", "title": "Custom-fit", "text": "Custom-fit means personalized with regard to shape and size. A customized product would imply the modification of some of its characteristics according to the customers requirements such as with a custom car. However, when fit is added to the term, customization could give the idea of both the geometric characteristics of the body and the individual customer requirements, \"e.g.\", the steering wheel of the Formula 1 driver Fernando Alonso.\nThe custom-fit concept can be understood as the idea of offering one-of-a-kind products that, due to their intrinsic characteristics and use, can be totally adapted to geometric characteristics in order to meet the user requirements.\nWith this new concept, industry moves from a resource based manufacturing system to a knowledge based manufacturing system and from mass production to individual production. This encourages the Lean Production trend as established by Toyota, or in other words, an efficiency-based production.\nResearch.\nThere are some studies referring to the positive impacts this concept would have on society:\nThe research studies found in February 2008 on the subject are the following:\nTechnical Tools.\nData Capturing.\nThe process starts with the capturing of data directly from the user by CAD techniques with the ultimate aim of manufacturing products using CAM techniques.\nProcess Design and Validation.\nAlthough all these developments have been of great interest, the RM-processes have not fallen behind, due to improvement of new Rapid Prototyping Direct digital manufacturing techniques.\nRapid Manufacturing Systems, Tools and Materials.\nMPP aims to become the equivalent of a high speed 3D-printer that produces three-dimensional objects directly from powder materials. This technique is based on the process principles of xerographic printers, (for example, laser or LED printers) that combine electrostatic printing with photography. The MPP process approach uses the same fundamental principles to build solid objects on a layer-by-layer basis. Layers of powder materials are generated by attracting different metal- and/or ceramic powders to their respective position on a charged pattern on a photoreceptor by means of an electrostatic field. The attracted layer is transferred to a punch and transported to the consolidation unit where each layer of part material is sintered onto the previous by pressure and heat. The procedure is repeated layer-by-layer until the three-dimensional object is fully formed and consolidated.\nMPP has the ability to print different powders within the same layer and progressively change from one material to another, i.e., producing a functionally graded material. In addition to this, MPP uses external pressure to speed the densification process (sintering), which allows manufacturing with a wide range of materials and opens the possibility to produce unique material combinations and microstructures.\nIt has several print heads that produce continuous streams of material droplets at high frequency. The High Viscosity Inkjet Printing machine is also capable of printing multi-materials simultaneously and also enables the mixing and grading of materials in any combination that is desired. This will enable the manufacturing of products with two or more materials that are graded and there will be no distinct boundary between the materials. This will result in products with unique mechanical properties.\nDr. Michiel Willemse who is leading the project says, \"The process is unique in its capability to print highly viscous, UV curable, resins. Material formulations with viscosities up to 500 mPa•s (at ambient temperature) have been printed successfully. This offers the opportunity to print products with unequaled mechanical properties when compared to any other printing systems.\"", "Engineering,_Manufacturing": 0.9999953508, "qwen": "Yes"}
{"id": "30157262", "revid": "829949", "url": "https://en.wikipedia.org/wiki?curid=30157262", "title": "Castrol India", "text": "Castrol India Limited is an automotive and industrial lubricant manufacturing company. Castrol India is the 2nd largest manufacturer of automotive and industrial lubricants in the Indian lubricant market and owns around 20% market share in the overall Indian lubricant market. It is part of Castrol Limited UK (part of BP Group). It has 5 manufacturing plants that are networked with 270 distributors, serving over 70,000 retail outlets.\nHistory.\nIn 1910, Castrol India started importing certain automotive lubricants from C C Wakefield & Company made an entry in the Indian market. In 1979, CIL was incorporated under the name of Indrol Lubricants and Specialities Pvt Ltd. It was listed on BSE in 1982 and CIL was converted into a public limited company. CIL had formed a subsidiary Company in the year 1987 under the name of Indtech Speciality Chemicals, Ltd.\nOn 1 November 1990, the name of the company was changed from Indrol Lubricants & Specialities Ltd. to Castrol India Ltd. It helped to manufacture of Telephone cable jellies, pharmaceuticals jellies and industrial waxes in technical collaboration with Dussek Campbell, U.K.\nAs of December 2019, there were talks ongoing between Reliance Industries and BP for setting up fuel stations in India where Castrol's products will be sold.\nProducts.\nCorrosion preventives, industrial lubricants, metalworking fluids, high temperature grease,cutting oil, automotive oil, neat cutting oil, cleaners", "Engineering,_Manufacturing": 0.9995254278, "qwen": "Yes"}
{"id": "18203431", "revid": "461300", "url": "https://en.wikipedia.org/wiki?curid=18203431", "title": "Plant layout study", "text": "A plant layout study is an engineering study used to analyze different physical configurations for a manufacturing plant. It is also known as Facilities Planning and Layout.\nOverview.\nThe ability to design and operate manufacturing facilities that can quickly and effectively adapt to changing technological and market requirements is becoming increasingly important to the success of any manufacturing organization. In the face of shorter product life cycles, higher product variety, increasingly unpredictable demand, and shorter delivery times, manufacturing facilities dedicated to a single product line cannot be cost effective any longer. Investment efficiency now requires that manufacturing facilities be able to shift quickly from one product line to another without major retooling, resource reconfiguration, or replacement of equipment.\nInvestment efficiency also requires that manufacturing facilities be able to simultaneously make several products so that smaller volume products can be combined in a single facility and that fluctuations in product mixes and volumes can be more easily accommodated. In short, manufacturing facilities must be able to exhibit high levels of flexibility and robustness despite significant changes in their operating requirements.\nIn industry sectors, it is important to manufacture the products which have good quality and meet customers’ demand. This action could be conducted under existing resources such as employees, machines and other facilities. However, plant layout improvement, could be one of the tools to response to increasing industrial productivity. Plant layout design has become a fundamental basis of today’s industrial plants which can influence parts of work efficiency. It is needed to appropriately plan and position employees, materials, machines, equipment, and other manufacturing supports and facilities to create the most effective plant layout.\nThe intended products to be manufactured influence the choice of layout.", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "38049822", "revid": "910180", "url": "https://en.wikipedia.org/wiki?curid=38049822", "title": "Coherence scanning interferometry", "text": "Coherence scanning interferometry (CSI) is any of a class of optical surface measurement methods wherein the localization of interference fringes during a scan of optical path length provides a means to determine surface characteristics such as topography, transparent film structure, and optical properties. CSI is currently the most common interference microscopy technique for areal surface topography measurement. The term \"CSI\" was adopted by the International Organization for Standardization (ISO).\nThe technique encompasses but is not limited to instruments that use spectrally broadband, visible sources (white light) to achieve interference fringe localization. CSI uses either fringe localization alone or in combination with interference fringe phase, depending on the surface type, desired surface topography repeatability and software capabilities. The table below compiles alternative terms that conform at least in part to the above definition.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "18772970", "revid": "45953770", "url": "https://en.wikipedia.org/wiki?curid=18772970", "title": "Beam lead technology", "text": "Beam lead technology is a method of fabricating a semiconductor device. Its initial application was for high-frequency silicon switching transistors and high-speed integrated circuits. This technology eliminated the labor-intensive wire-bonding process that was commonly used for integrated circuits at the time. It also enabled the automated assembly of semiconductor chips onto larger substrates, facilitating the production of hybrid integrated circuits. \nHistory.\nIn the early 1960s, M.P. Lepselter developed techniques for fabricating a structure that involved electroforming an array of thick, self-supporting gold patterns on a thin film Ti-Pt-Au base, leading to the term \"beams.\" These patterns were deposited on the surface of a silicon wafer. The excess semiconductor material beneath the beams was subsequently removed, resulting in the separation of individual devices and leaving them with self-supporting beam leads or internal chiplets cantilevered beyond the semiconductor material. These contacts not only served as electrical leads but also provided structural support for the devices.\nPatents.\nPatented inventions included:\nLegacy.\nThis technology, also known as air-bridge technology, has established itself for its unsurpassed reliability in high-frequency silicon switching transistors and ultra-high-speed integrated circuits for telecommunications and missile systems. The beam lead devices, produced by the hundreds of millions, became the first example of a commercial microelectromechanical structure (MEMS).", "Engineering,_Manufacturing": 1.0000083447, "qwen": "Yes"}
{"id": "18785490", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=18785490", "title": "Renault AX", "text": "The Renault AX is an automobile manufactured by Renault. It was produced between 1908 and 1914 and was mostly used by cab drivers.\nThe AX had a 2-cylinders straight engine with a displacement of 1,060 cc and a power of 8 kW. Its maximum speed was 35 mph (56 km/h). The vehicle weighed 750 kg.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "33483656", "revid": "45805768", "url": "https://en.wikipedia.org/wiki?curid=33483656", "title": "Manufacturing Advisory Service", "text": "The Manufacturing Advisory Service (MAS) is a former government agency in England and Scotland.\nHistory.\nIt was founded by the Department of Trade and Industry (DTI, which became BERR in 2007) in April 2002. It was split into regions and was aimed at SMEs to offer technical and strategic advice. The regional offices were titled Regional Centres of Manufacturing Excellence. There was also co-operation with trade associations, research councils and university departments. In the first year the MAS had on average improved companies productivity by 30%, reduced waste by 37%, and increased inventory turnover by 90%. It had been launched with £27 million funding for three years. (50% Government and 50% Regional) The concept for MAS was based on US model the Manufacturing Extension Programme (MEP). A DTI official who had seen the programme in US brought the model back and developed it for the UK.\nIn many ways it is similar to what Business Link provides for all small businesses, except that Business Link may not have the in-depth experience of manufacturing, specifically the technical know-how. From November 2011 Business Link is mostly to be disbanded, due to abolishment of regional development agencies (RDAs), and replaced with regional websites.\nMuch of Business Link's advice was previously via its extensive website. Like Business Link, MAS was funded through RDAs. Half of the MAS's funding came from its RDA and the other half came from BIS.\nOverhaul.\nOn 14 October 2011 Mark Prisk, a minister at the BIS, announced an overhaul of the MAS. It will offer much of what it has done, but due to the regional development agencies being abolished, it will be a national organisation from 1 January 2012. The new national programme will be delivered by the Manufacturing Advisory Consortium comprising Grant Thornton, Pera, WM Manufacturing Consortium Ltd, and SWMAS Ltd.\nOn 10 December 2010 he had announced that the MAS would not be abolished, as Business Link will be, but will have a 25% cut in funding. It is costing £20 million a year, which will be reduced to £15 million. For the last financial year Business Link received £190 million.\nClosure.\nWith no warning, on 27 November 2015, the closure of the Manufacturing Advisory Service was announced as part of the conservative government austerity programme, with the programme formally closing on 31 March 2016.\nRelaunch.\nIn April 2017 following a high-level meeting with a consortium of Manufacturing MD's and CEO's in Birmingham led by Lord Mike Whitby and Baroness Lorely Burt, Manufacturing Advisory Service was asked to be relaunched by voices from industry. No longer reliant on government funding, MAS through its place on the All Parliamentary Manufacturing Group and its operational delivery by the Made in Brand will continue to offer the signposting service of Manufacturing Advisory Service, but not a grant funding arm.\nAs a result, the re-launch of the Manufacturing Advisory Service is not like the old service in any way.\nIn October 2016, a further programme was created to fill the void left by MAS by providing access to specialist support, free advice and grant funding to help SME Manufacturers grow and improve their businesses. \nThe Manufacturing Growth Programme, managed by those who ran the MAS programme for 10+ years across the West Midlands, East Midlands, Yorkshire and Humber, North West, and South regions, the new programme is also delivered by a number of previous MAS Advisors across 16 LEP regions who offer real advice and sustainable support.\nThe Manufacturing Growth Programme, is the new and only business support initiative to help support SME Manufacturers.\nManufacturing Growth Programme.\nIn October 2016, SME Manufacturers were given a major boost with a new £9.7m business support initiative to support over 3,000 companies.\nFunded by ERDF and delivered by Economic Growth Solutions (EGS), the Manufacturing Growth Programme promises to fill the void left by MAS by providing access to specialist assistance to help firms grow and improve.\nWith an 18-strong network of experienced Manufacturing Growth Managers, the majority of which previously delivered the MAS programme, providing bespoke honest advice, MGP also provides access to industry specialists and grant funding to support improvement projects.\nIn July 2017, the programme had supported more than 1,000 SME Manufacturers, created more than 400 new jobs for the industry and enabled companies to make sustainable changes to support continuous growth.\nFunction.\nIt has a helpline for advice. It can conduct a free Manufacturing Review on SME manufacturers, and offers subsidised consultancy (up to 50%), and has local events.\nThe support offered by the Manufacturing Advisory Service covers\nLevel 1 (Enquiries) Provided by a small team of advisors geographically dispersed round England supported by a website offering online support.\nLevel 2 (Manufacturing Review) Continue to provide 1 day (2 days for more complex businesses), on-site specialist manufacturing diagnostic review. MAC will use a new diagnostic tool based on the principles of \"Manufacturing Excellence\" developed in conjunction with the Warwick Manufacturing Group which includes comparisons against best-in-class. In addition, a \"Fast Track\" over the 'phone Level 2 will be introduced for common, well understood issues.\nLevel 3 (Events) Continue to provide training and networking events, including best practice visits. These will be an integral part of delivering the Business Improvement actions identified at Level 2. This will be complemented by a Sustainable Improvement Community using best practice social networking tools to provide peer-led best practice examples and lower cost forms of self-help.\nLevel 4 (Consultancy) \nIntroduction of a three tier Level 4 project structure:\n· MAS Foundation Service: Funding up to £1,000 (or a maximum of 50%) towards an improvement project - targeted at companies who need basic low-level help.\n· MAS Step Change Service: Funding of up to £3,000 (or 50% maximum) towards a more significant improvement programme.\n· MAS Transformation Service: Funding of up to £10,000 (or 50% maximum) for a strategic change to the business.\nLevel 5 (Referrals) MAS advisors are responsible for identifying partner organisation support but retain responsibility for referral until it is demonstrated and confirmed by the client that the partner organisation has addressed the client need.\nSupply Chain Focus on helping SMEs diversify into advanced manufacturing supply\nchains; helping original equipment manufacturers and their supply chains develop better relationships and greater efficiency; helping groups of SMEs in supply chains or clusters interact more effectively. It will use the tools available through Levels 1 - 5 with custom implementation packages assembled to suit client needs delivered by a team of dedicated supply chain experts.", "Engineering,_Manufacturing": 1.0000056028, "qwen": "Yes"}
{"id": "21196962", "revid": "14724352", "url": "https://en.wikipedia.org/wiki?curid=21196962", "title": "Krones", "text": "Krones AG is a German packaging and bottling machine manufacturer. It produces lines for filling beverages in plastic and glass bottles or beverage cans. The company manufactures stretch blow-moulding machines for producing polyethylene terephthalate (PET) bottles, plus fillers, labellers, bottle washers, pasteurisers, inspectors, packers and palletisers. This product portfolio is complemented by material flow systems and process technology for producing beverages for breweries, dairies and soft-drink companies.\nHistory.\nKrones' corporate evolution is closely connected to the socioeconomic conditions prevalent in Germany following World War II. Hermann Kronseder, the father of the present-day chairman of the supervisory board, used his own designs to manufacture semi-automatic labellers starting with 1951. In the further development as from the 1960s, the firm's range of machinery was extended to include packers and filling systems. In 1980, the company was converted into a stock corporation as Krones AG.\nWith acquisitions of other companies the present-day range of machines for the beverage industry was reached:\nCorporate data.\nThe headquarters of the group is situated in Neutraubling near Regensburg, Germany. In Germany in total 10,733 people are employed. Machines and systems are manufactured at the German production facilities (Neutraubling, Nittenau, Flensburg, Freising and Rosenheim). From 2019 on a fabrication site in Debrecen, Hungary, completes production facilities. The internationally focused company achieves more than 90% of its total turnover abroad and is represented worldwide through around 90 subsidiaries and shareholdings. The intralogistics business of Krones is handled by Syskron Holding GmbH since 2014. \nSubsidiaries\nCover additional market segments in beverage filling.\nIn the year 2019 the enterprise held 5,877 patents and utility models.\nCorporate structure.\nPlastics engineering\nStretch blow-moulding machines for the production of PET bottles of up to a volume of 3 liters, with an output of 12,800 to 90,000 bottles/hour. The PET recycling system is based on a PET Flakes cleaning process equipped with progressive temperature controls and decontamination.\nFilling and packing technology\nRinse, filling and capping lines with a rotary concept. With rotary lines, high-speed tasks of up to 72,000 bottles/hour or approximately 120,000 cans/hour are possible, including aseptic filling systems for beverages with a high pH value (> 4,5). For the disinfection of containers and closures, PES or H2O2 is used. Further steps in beverage production as bottle-washing machines, inspection and control systems for bottles and bundles, as well as labelling machines for cold and hot glue or self-adhesive labelling complete the product range. Packaging machines for bundles either one-way or returnable, sorting and grouping stations, as well as palletisation systems supplement the spectrum.\nProcess engineering\nBreweries can be completely equipped with brewhouses, including fermenting and storage cellar equipment, along with assigned supply installations. For manufacturing plants of non-alcoholic beverages' syrup areas, mixing and carbonising equipment are supplied. Heating systems as UHT- and flash heating systems or pasteurizing systems are available for beverage preservation.\nIT solutions and material handling systems\nThe control of production process and the integration of production data into an ERP system. Logistics systems provide production and distribution with raw, operating and auxiliary materials, as well as finished products, with either block storage or automatic warehouse systems, including commissioning equipment, forklift guidance and yard management systems for logistics process in beverage and food plants. Activities for logistics have been pooled in System Logistics, a legally independent unit.\nBusiness figures.\nExecutive board\nChairman of the supervisory board: Volker Kronseder", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "21209174", "revid": "6036800", "url": "https://en.wikipedia.org/wiki?curid=21209174", "title": "Computer-aided process planning", "text": "Computer-aided process planning.\nAs the design process is supported by many computer-aided tools, computer-aided process planning (CAPP) has evolved to simplify and improve process planning and achieve more effective use of manufacturing resources.\nProcess Planning is of two types:\nRoutings that specify operations, operation sequences, work centers, standards, tooling, and fixtures. This routing becomes a major input to the manufacturing resource planning system to define operations for production activity control purposes and define required resources for capacity requirements planning purposes.\nComputer-aided process planning initially evolved as a means to electronically store a process plan once it was created, retrieve it, modify it for a new part and print the plan.\nOther capabilities were table-driven cost and standard estimating systems, for sales representatives to create customer quotations and estimate delivery time.\nFuture development.\nGenerative or dynamic CAPP is the main focus of development, the ability to automatically generate production plans for new products, or dynamically update production plans on the basis of resource availability. Generative CAPP will probably use iterative methods, where simple production plans are applied to automatic CAD/CAM development to refine the initial production plan.\nA Generative CAPP system was developed at Beijing No. 1 Machine Tool Plant (BYJC) in Beijing, China as part of a UNDP project (DG/CRP/87/027) from 1989 to 1995. The project was reported in \"Machine Design Magazine; New Trends\" May 9, 1994, P.22-23. The system was demonstrated to the CASA/SME Leadership in Excellence for Applications Development (LEAD) Award committee in July 1995. The committee awarded BYJC the LEAD Award in 1995 for this achievement. In order to accomplish Generative CAPP, modifications were made to the CAD, PDM, ERP, and CAM systems. In addition, a Manufacturing Execution System (MES) was built to handle the scheduling of tools, personnel, supply, and logistics, as well as maintain shop floor production capabilities.\nGenerative CAPP systems are built on a factory's production capabilities and capacities. In Discrete Manufacturing, Art-to-Part validations have been performed often, but when considering highly volatile engineering designs, and multiple manufacturing operations with multiple tooling options, the decisions tables become longer and the vector matrices more complex. BYJC builds CNC machine tools and Flexible Manufacturing Systems (FMS) to customer specifications. Few are duplicates. The Generative CAPP System is based on the unique capabilities and capacities needed to produce those specific products at BYJC. Unlike a Variant Process Planning system that modifies existing plans, each process plan could be defined automatically, independent of past routings. As improvements are made to production efficiencies, the improvements are automatically incorporated into the current production mix. This generative system is a key component of the CAPP system for the Agile Manufacturing environment.\nIn order to achieve the Generative CAPP system, components were built to meet needed capabilities:\nThe parameters are used to produce multidimensional differential equations. Solving the partial differential equations will produce the optimum process and production planning at the time when the solution was generated. Solutions had the flexibility to change over time based on the ability to satisfy agile manufacturing criteria. Execution planning can be dynamic and accommodate changing conditions.\nThe system allows new products to be brought on line quickly based on their manufacturability. The more sophisticated CAD/CAM, PDM and ERP systems have the base work already incorporated into them for Generative Computer Aided Process Planning. The task of building and implementing the MES system still requires identifying the capabilities that exist within a given establishment, and exploiting them to the fullest potential. The system created is highly specific, the concepts can be extrapolated to other enterprises.\nTraditional CAPP methods that optimize plans in a linear manner have not been able to satisfy the need for flexible planning, so new dynamic systems will explore all possible combinations of production processes, and then generate plans according to available machining resources. For example, K.S. Lee et al. states that \"By considering the multi-selection tasks simultaneously, a specially designed genetic algorithm searches through the entire solution space to identify the optimal plan\".", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "21215294", "revid": "31612503", "url": "https://en.wikipedia.org/wiki?curid=21215294", "title": "Flats Sequencing System", "text": " Flats Sequencing System (FSS) is an automated system used by the US Postal Service. It uses a dual pass sort technique to sort flats all the way to delivery sequence order. Prior to the deployment of FSS machines, flats were machine sorted to the route level only. Carriers had to manually sort all the flats they were to deliver into proper delivery order before they could embark on their routes. With FSS, when the carrier receives them they are ready to be delivered without need for any further manual sorting.\nFSS machines are manufactured by Northrop Grumman. Deployment began in 2008.", "Engineering,_Manufacturing": 0.9999887943, "qwen": "Yes"}
{"id": "63674284", "revid": "10666778", "url": "https://en.wikipedia.org/wiki?curid=63674284", "title": "Multilayered packaging", "text": "Multi-layered packaging are multilayer or composite materials using innovative technologies aimed to give barrier properties, strength and storage stability to food items, new materials as well as hazardous materials.\nMultiple layers are formed by coextrusion, lamination\n, or various coating technologies. The material of construction of multilayered packaging ranges from paper to plastics to metals. Most multilayered packages are not readily recyclable. Basf company and Uflex recently developed multilayered food packaging from 100% recyclable materials.\nHistory of multilayered packaging dates back to the late 1950s when Procter & Gamble first designed multilayered collapsible tubes for toothpastes. \nAmine group containing products deforms HDPE on storage, and are incapable of arresting amine odours. Multilayered CO-EX bottles are the best packaging solution for such products. \nTypes.\nMultiwall paper sacks.\nThese are made of multiple layers of extensible kraft paper of differing grammages. These are gaining popularity in the cement industry, drug and fertilizer industry where the inner or outer layer of the sacks are made of polyethylene to protect the product from moisture.\nLaminated-cartons and plastic bottles.\nThese find use in paint industry, tetra packs containing milk, fruit juice, syrups and pharmaceutical industry. The typical combinations are as follows:\nApart from these nylon, EVOH, EAA, PA, EVA, SiO2 plasma coatings are also used in laminates to give various functional properties. The layer combinations are selected by the engineer depending on the product characteristic, shelf life and extent of vapour transmission rate. Precooked food are packed in PS/EVOH/PE bags with PVE/PDVC/PE closures.\nCoextrusion.\nCoextrusion is the plastic extrusion of multiple layers of material simultaneously. Such products are popularly known as CO-EX.", "Engineering,_Manufacturing": 0.9984433055, "qwen": "Yes"}
{"id": "52787040", "revid": "1134906589", "url": "https://en.wikipedia.org/wiki?curid=52787040", "title": "CFSMC", "text": "CFSMC, or Carbon Fiber Sheet Molding Compound (also known as CSMC or CF-SMC), is a ready to mold carbon fiber reinforced polymer composite material used in compression molding. While traditional SMC utilizes chopped glass fibers in a polymer resin, CFSMC utilizes chopped carbon fibers. The length and distribution of the carbon fibers is more regular, homogeneous, and constant than the standard glass SMC. CFSMC offers much higher stiffness and usually higher strength than standard SMC, but at a higher cost.\nManufacturing.\nCF-SMC are made up of carbon tow chunks, spread between two layers of uncured thermosetting resin. The carbon fibre tows are cut from prepreg UD tape. The originating tape can be made up of a certain number of fibres (filaments), thus affecting the properties of the final composite: values can vary from 3 to 50 thousand filaments, while typical tow lengths are within 10 to 50 mm. As for the resin, thermosetting resins are used: possible choices are polyester, vinyl ester or epoxy, with the former being the cheapest and the latter being the most performant. Despite not being as strong nor stiff as epoxy, vinyl ester is often used for its properties like corrosion and higher temperature resistance. The constituents are combined in sheets of prepreg material. The tows usually fall from the cutter onto one of the two layers of resin, and are then covered by the second layer. The prepreg sheets of SMC are made after the viscous assembly is compacted via rollers. In this phase, any control over the orientation of the fibres is generally impossible, and the fibres can be considered to have an equiprobable orientation in all directions.\nOnce the prepreg sheets are made, the material can be compression moulded into the final desired shape. Compression moulding is a manufacturing technique that requires a two part mould: the first one hosts the moulding material (charge), while the second one is mounted on a press to close the cavity while applying high pressure. Due to complex geometry, it may be necessary to cut the sheets to place them more easily in the lower mould. Then, while the upper mould cavity is closing, the material is pushed throughout the mould until closed. Pressure is maintained, together with elevated temperature, to allow the curing of the resin and low porosity. This stage has a heavy influence on the mechanical performances of the final product, as the viscous flow into the mold cavity tends to orient the fibers along the direction of the flow. By controlling the amount and direction of the flow, it is thus possible to influence the fibre orientation, having a quasi-isotropic material (low-flow moulding) or higher performances in a desired direction (high-flow moulding).\nDuring the manufacturing phase, it is also important to avoid, when possible, defects like weld-\nlines. Weld lines occur when two flow fronts of material meet during the filling of a mold cavity. This can sometimes result in air entrapment, inhibited crosslinking in the polymer matrix, or the clumping or absence of fibers. For these reasons weld-lines can be as weak or weaker than the neat polymer resin.\nMaterial Properties.\nDue to their heterogeneous and anisotropic microstructure, mechanical properties of CF-SMC can vary significantly within broad ranges. Parameters having profound impact on these materials performances are mainly related to the fibres and matrix neat mechanical and geometrical properties (especially those of the fibres) and the orientation and content of the reinforcement. Modulus can vary from less than 20 GPa to 60 GPa, while strength values are within 60-500 MPa.\nCF-SMC can also be engineered, to some extent, to have better performances in a specific direction, in a similar fashion as continuous fibres composites. This can be achieved by carefully controlling the compression moulding stage to influence fibre orientation. When the fibres are mainly aligned with the loading direction, the material behaviour is mainly dominated by that of the fibres, thus resulting in stronger and stiffer, but also more brittle response. In the opposite case, if fibres tend to dispose perpendicular to the loading direction, the resin contributes more to the load bearing, and the overall composite will be less stiff, less strong and more ductile. Being based on hydrodynamic transport phenomena, however, the control over fibre orientation in CF-SMC is much more limited than in the continuous composites case, where orientation is often directly determined accurately by the manufacturer. In addition, while continuous fibres composites have a specific orientation, short fibre reinforced plastics can have a preferential orientation, meaning that, considering a generic system of axis, the majority of fibres can have a higher component along a direction and a lower component along the other two axis.\nThe discontinuous tow-based microstructure of these materials makes is even more heterogeneous than standard composites: fibre ends themselves acts as stress concentration areas for both the resin and the neighbouring tows; moreover, especially for complex shaped parts, it is impossible to prevent some local spots with badly aligned tows (e.g. perpendicular to the direction of axial stress) or with low fibre volume content, like resin pockets. Although making the material weaker and the structural design more complex, this feature makes these materials quite notch-insensitive.\nWhen moulded, CFSMC has a very different appearance than traditional carbon fibre fabric composites, which traditionally appear with a woven checkerboard pattern. CFSMC has the appearance of black and grey marble or burl.\nIndustrial use.\nCF SMC combines the lightweight properties of carbon composites with a manufacturing process, as compression moulding, that allows fast manufacturing and thus is suitable for high volume industrial applications. For these reasons, the automotive industry is one of the best candidates for this technology.\nCar manufacturers have used standard glass SMC for over 30 years as a material for body panels in select sport cars such as the Chevrolet Corvette. Substituting glass fibres with carbon is a recent development, having been used for significant structural components of the 2003 Dodge Viper, the multifunctional spare wheel pan of Mercedes-AMG E-Class, the Mercedes-Benz SLR McLaren, the 2009 Lexus LFA, 2015 Lamborghini Huracán, the 2017 BMW 7 series and 2017 McLaren chassis. Lamborghini (together with Callaway Golf Company) patented an advanced version of CF-SMC called Forged Composite. They first introduced it in the Sesto Elemento concept car, and since then, Forged Composite has been a distinctive mark for Lamborghini cars, used both in structural and aesthetical purposes. CF-SMC use is recently spreading also to the much broader non-high performance automotive sector as for the 2017 Toyota Prius PHV.\nCF-SMC has also been used in the aeronautic industry by Boeing, for the 787 Dreamliner window frames, while producers suggest that the use of these materials will grow in this sector as well.", "Engineering,_Manufacturing": 0.9999983311, "qwen": "Yes"}
{"id": "52791455", "revid": "196446", "url": "https://en.wikipedia.org/wiki?curid=52791455", "title": "RoboDK", "text": "RoboDK is an offline programming and simulation software for industrial robots. The simulation software can be used for many manufacturing projects including milling, welding, pick and place, packaging and labelling, palletizing, painting, robot calibration and more.\nMain Features.\nRobot Brand Independence.\nRoboDK has a library of over 500 robots from more than 50 different manufacturers including ABB, Fanuc, Kuka, Motoman, Hwashi Robots and Universal Robots.\nUser Interface.\nThe user interface enables easy simulation and doesn't require any previous programming knowledge.\nFile Format.\nDifferent types of files can be imported including step and iges files. RoboDK post processors allow for programs to be exported to an actual robot including, ABB Rapid (mod/prg), Fanuc LS (LS/TP), Kuka KRC/IIWA (SRC/java), Motoman Inform (JBI), Universal Robots (urscript), Hwashi (C＋＋), Kawasaki (Python and C＋＋) and more.", "Engineering,_Manufacturing": 0.9991477728, "qwen": "Yes"}
{"id": "16722485", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=16722485", "title": "Machinability", "text": "Machinability is the ease with which a metal can be cut (machined) permitting the removal of the material with a satisfactory finish at low cost. Materials with good machinability (free machining materials) require little power to cut, can be cut quickly, easily obtain a good finish, and do not cause significant wear on the tooling. Factors that typically improve a material's performance often degrade its machinability, presenting a significant engineering challenge.\nMachinability can be difficult to predict due to the large number of variables involved in the machining process. Two sets of factors are the condition of work materials and the physical properties of work materials. The condition of the work material includes at least eight factors: microstructure, grain size, heat treatment, chemical composition, fabrication, hardness, yield strength, and tensile strength. Physical properties are those of the individual material groups, such as the modulus of elasticity, thermal conductivity, thermal expansion, and work hardening. Other important factors are operating conditions, cutting tool material and geometry, and the parameters of the specific machining process being performed.\nMachinability of steels.\nSteels are among the most important and commonly used materials in engineering. Free machining steels are alloys that include elements like sulfur and lead that reduce the size of chips produced by the machining process. Free machining steels are more expensive than standard steels, but their cost is offset by savings on manufacturing costs.\nQuantifying machinability.\nThere are many factors affecting machinability, but no widely accepted way to quantify it. Instead, machinability is often assessed on a case-by-case basis, and tests are tailored to the needs of a specific manufacturing process. Common metrics for comparison include tool life, surface finish quality, cutting temperature, tool forces, and power consumption.\nTool life method.\nMachinability can be based on the measure of how long a tool lasts. This can be useful when comparing materials that have similar properties and power consumptions, but one is more abrasive and thus decreases the tool life. The major downfall with this approach is that tool life is dependent on more than just the material it is machining; other factors include cutting tool material, cutting tool geometry, machine condition, cutting tool clamping, cutting speed, feed, and depth of cut. Also, the machinability for one tool type cannot be compared to another tool type (i.e. HSS tool to a carbide tool).\nformula_1\nTool forces and power consumption method.\nThe forces required for a tool to cut through a material is directly related to the power consumed. Therefore, tool forces are often given in units of specific energy. This leads to a rating method where higher specific energies equal lower machinability. The advantage of this method is that outside factors have little effect on the rating.\nSurface finish method.\nThe surface finish is sometimes used to measure the machinability of a material. Soft, ductile materials tend to form a built up edge. Stainless steel and other materials with a high strain hardening ability also want to form a built up edge. Aluminium alloys, cold worked steels, and free machining steels, as well as materials with a high shear zone don't tend to form built up edges, so these materials would rank as more machinable.\nThe advantage of this method is that it is easily measured with the appropriate equipment. The disadvantage of this criterion is that it is often irrelevant. For instance when making a rough cut, the surface finish is of no importance. Also, finish cuts often require a certain accuracy that naturally achieves a good surface finish. This rating method also doesn't always agree with other methods. For instance titanium alloys would rate well by the surface finish method, low by the tool life method, and intermediate by the power consumption method.\nMachinability rating.\nThe machinability rating of a material attempts to quantify the machinability of various materials. It is expressed as a percentage or a normalized value. The American Iron and Steel Institute (AISI) determined machinability ratings for a wide variety of materials by running turning tests at 180 surface feet per minute (sfpm). It then arbitrarily assigned 160 Brinell B1112 steel a machinability rating of 100%. The machinability rating is determined by measuring the weighted averages of the normal cutting speed, surface finish, and tool life for each material. Note that a material with a machinability rating less than 100% would be more difficult to machine than B1112 and material with a value more than 100% would be easier.\nMachinability Rating= (Speed of Machining the workpiece giving 60min tool life)/( Speed of machining the standard metal)\nMachinability ratings can be used in conjunction with the Taylor tool life equation, formula_2, in order to determine cutting speeds or tool life. It is known that B1112 has a tool life of 60 minutes at a cutting speed of 100 sfpm. If a material has a machinability rating of 70%, it can be determined, with the above knowns, that in order to maintain the same tool life (60 minutes) the cutting speed must be 70 sfpm (assuming the same tooling is used).\nSteels.\nThe carbon content of steel greatly affects its machinability. High-carbon steels are difficult to machine because they are strong and because they may contain carbides that abrade the cutting tool. On the other end of the spectrum, low-carbon steels are troublesome because they are too soft. Low-carbon steels are \"gummy\" and stick to the cutting tool, resulting in a built up edge that shortens tool life. Therefore, steel has the best machinability with medium amounts of carbon, about 0.20%.\nChromium, molybdenum and other alloying metals are often added to steel to improve its strength. However, most of these metals also decrease machinability.\nInclusions in steel, especially oxides, may abrade the cutting tool. Machinable steel should be free of these oxides.\nAdditives.\nThere are a variety of chemicals, both metal and non-metal, that can be added to steel to make it easier to cut. These additives may work by lubricating the tool-chip interface, decreasing the shear strength of the material, or increasing the brittleness of the chip. Historically, sulfur and lead have been the most common additives, but bismuth and tin are increasingly popular for environmental reasons.\nLead can improve the machinability of steel because it acts as an internal lubricant in the cutting zone. Since lead has poor shear strength, it allows the chip to slide more freely past the cutting edge. When it is added in small quantities to steel, it can greatly improve its machinability while not significantly affecting the steel's strength.\nSulfur improves the machinability of steel by forming low shear strength inclusions in the cutting zone. These inclusions are stress risers that weaken the steel, allowing it to deform more easily.\nStainless steel.\nStainless steels have poor machinability compared to regular carbon steel because they are tougher, gummier and tend to work harden very rapidly. Slightly hardening the steel may decrease its gumminess and make it easier to cut. AISI grades 303 and 416 are easier to machine because of the addition of sulfur and phosphorus.\nAluminium.\nAluminium is a much softer metal than steel, and the techniques to improve its machinability usually rely on making it more brittle. Alloys 2007, 2011 and 6020 have very good machinability.\nOther materials.\nThermoplastics are difficult to machine because they have poor thermal conductivity. This creates heat that builds up in the cutting zone, which degrades the tool life and locally melts the plastic. Once the plastic melts, it just flows around the cutting edge instead of being removed by it. Machinability can be improved by using high lubricity coolant and keeping the cutting area free of chip build up.\nComposites often have the worst machinability because they combine the poor thermal conductivity of a plastic resin with the tough or abrasive qualities of the fiber (glass, carbon etc.) material.\nThe machinability of rubber and other soft materials improves by using a very low temperature coolant, such as liquid carbon dioxide. The low temperatures chill the material prior to cutting so that it cannot deform or stick to the cutting edge. This means less wear on the tools and easier machining.", "Engineering,_Manufacturing": 1.0000076294, "qwen": "Yes"}
{"id": "16722903", "revid": "45748661", "url": "https://en.wikipedia.org/wiki?curid=16722903", "title": "Abrasive machining", "text": "Abrasive machining is a machining process where material is removed from a workpiece using a multitude of small abrasive particles. Common examples include grinding, honing, and polishing. Abrasive processes are usually expensive, but capable of tighter tolerances and better surface finish than other machining processes\nMechanics of abrasive machining.\nAbrasive machining works by forcing the abrasive particles, or grains, into the surface of the workpiece so that each particle cuts away a small bit of material. Abrasive machining is similar to conventional machining, such as milling or turning, because each of the abrasive particles acts like a miniature cutting tool. However, unlike conventional machining the grains are much smaller than a cutting tool, and the geometry and orientation of individual grains are not well defined. As a result, abrasive machining is less power efficient and generates more heat.\nThe grain size may be different based on the machining. For rough grinding, coarse abrasives are used. For fine grinding, fine grains (abrasives) are used.\nAbrasive machining processes.\nAbrasive machining processes can be divided into two categories based on how the grains are applied to the workpiece.\nIn bonded abrasive processes, the particles are held together within a matrix, and their combined shape determines the geometry of the finished workpiece. For example, in grinding the particles are bonded together in a wheel. As the grinding wheel is fed into the part, its shape is transferred onto the workpiece.\nIn loose abrasive processes, there is no structure connecting the grains. They may be applied without lubrication as dry powder, or they may be mixed with a lubricant to form a slurry. Since the grains can move independently, they must be forced into the workpiece with another object like a polishing cloth or a lapping plate.\nCommon abrasive processes are listed below.\nAbrasives.\nThe most important property of an abrasive is its hardness. For abrasive grains to effectively cut, they must be significantly harder than the workpiece material. They can be grouped based on their hardness into two categories: conventional abrasives and superabrasives.\nConventional abrasive materials have been used since the advent of machining. They are made of materials that exist naturally on Earth, and they are abundant and cheap. Conventional abrasives can suitably machine most materials.\nSuperabrasives are much harder than conventional abrasives. Since they are much more expensive, they are used when conventional abrasives will not suffice.\nCommon abrasives are listed below.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "4083646", "revid": "41315924", "url": "https://en.wikipedia.org/wiki?curid=4083646", "title": "Electrofusion", "text": "Electrofusion is a method of joining MDPE, HDPE and other plastic pipes using special fittings that have built-in electric heating elements which are used to weld the joint together.\nThe pipes to be joined are cleaned, inserted into the electrofusion fitting (with a temporary clamp if required) and a voltage (typically 40V) is applied for a fixed time depending on the fitting in use. The built in heater coils then melt the inside of the fitting and the outside of the pipe wall, which weld together producing a very strong homogeneous joint. The assembly is then left to cool for a specified time.\nElectrofusion welding is beneficial because it does not require the operator to use dangerous or sophisticated equipment. After some preparation, the Electrofusion Welder will guide the operator through the steps to take. Welding Heat and Time is dependent on the type and size of the fitting. All Electrofusion Fittings are not created equal - Precise positioning of the energising coils of wire in each fitting ensures uniform melting for a strong joint and the minimisation of welding and cooling time.\nThe operator must be qualified according to the local and national laws. In Australia, an Electrofusion Course can be done within 8 hours. Electrofusion welding training focuses on the importance of accurately fusing EF fittings. Both manual and automatic methods of calculating electrofusion time gives operators the skills they need in the field. There is much to learn about the importance of preparation, timing, pressure, temperature, cool down time and handling, etc.\nTraining and certification are very important in this field of welding, as the product can become dangerous under certain circumstances. There has been cases of major harm and death, including when molten polyethylene spurts out of the edge of a mis-aligned weld, causing skin burns. Another case was due to a tapping saddle being incorrectly installed on a gas line, causing the death of the two welders in the trench due to gas inhalation. There are many critical parts to Electrofusion welding that can cause weld failures, most of which can be greatly reduced by using welding clamps, and correct scraping equipment.\nTo keep their qualification current, a trained operator can get their fitting tested, which involves cutting open the fitting and examining the integrity of the weld.", "Engineering,_Manufacturing": 1.0000036955, "qwen": "Yes"}
{"id": "4086824", "revid": "43803003", "url": "https://en.wikipedia.org/wiki?curid=4086824", "title": "Selective soldering", "text": "Selective soldering is the process of selectively soldering components to printed circuit boards and molded modules that could be damaged by the heat of a reflow oven or wave soldering in a traditional surface-mount technology (SMT) or through-hole technology assembly processes. This usually follows an SMT oven reflow process; parts to be selectively soldered are usually surrounded by parts that have been previously soldered in a surface-mount reflow process, and the selective-solder process must be sufficiently precise to avoid damaging them.\nProcesses.\nAssembly processes used in selective soldering include:\nLess-common selective soldering processes include:\nOther selective soldering applications are non-electronic, such as lead-frame attachment to ceramic substrates, coil-lead attachment, SMT attachment (such as LEDs to PCBs) and fire sprinklers (where the fuse is low-temperature solder alloys).\nRegardless of the selective soldering equipment used, there are two types of selective flux applicators: spray and dropjet fluxers. The spray fluxer applies atomized flux to a specific area, while the dropjet fluxer is more precise; the choice depends on the circumstances surrounding the soldering application.\nMiniature wave selective solder fountain.\nThe miniature wave selective solder fountain type is widely used, yielding good results if the PCB design and manufacturing process are optimized. Key requirements for selective fountain type soldering are:\nDrop-Jet.\nThe Drop-Jet is an Electromechanical device which is capable of depositing a droplet of flux on demand onto a surface such as a Printed Circuit Board and or component pin.\nThermal Profiling.\nThe thermal profile of the selective process is critical as with other common automated soldering techniques.\nTopside temperature measurements within the pre-heat stage must be verified as with conventional flow solder machine, additionally flux activation must be verified as sufficient.\nAs number of miniature profiling dataloggers are now available to make the process more simple such as the Solderstar Pro units.\nSelective Solder Optimization.\nA number of fixtures are available to allow daily checking of the selective solder process, these instruments allow the verification of machine parameters to be performed on a periodic basis.\nParameters such as contact time, X/Y speeds, nozzle wave height and profile temperature can all be measured.\nUse of Nitrogen Atmosphere.\nSelective soldering is normally undertaken in a nitrogen atmosphere. This prevents oxidation of the fountain surface and results in better wetting. Less flux is needed with less left-over residue. The use of nitrogen results in clean, shiny joints without the need for PCB cleaning or brushing.", "Engineering,_Manufacturing": 1.0000078678, "qwen": "Yes"}
{"id": "4093822", "revid": "42727488", "url": "https://en.wikipedia.org/wiki?curid=4093822", "title": "System in a package", "text": "A system in a package (SiP) or system-in-package is a number of integrated circuits (ICs) enclosed in one chip carrier package or encompassing an IC package substrate that may include passive components and perform the functions of an entire system. The ICs may be stacked using package on package, placed side by side, and/or embedded in the substrate. The SiP performs all or most of the functions of an electronic system, and is typically used when designing components for mobile phones, digital music players, etc. Dies containing integrated circuits may be stacked vertically on a substrate. They are internally connected by fine wires that are bonded to the package. Alternatively, with a flip chip technology, solder bumps are used to join stacked chips together. SiPs are like systems on a chip (SoCs) but less tightly integrated and not on a single semiconductor die.\nTechnology.\nSiP dies can be stacked vertically or tiled horizontally, with techniques like chiplets or quilt packaging, unlike less dense multi-chip modules, which place dies horizontally on a carrier. SiPs connect the dies with standard off-chip wire bonds or solder bumps, unlike slightly denser three-dimensional integrated circuits which connect stacked silicon dies with conductors running through the die. Many different 3D packaging techniques have been developed for stacking many fairly standard chip dies into a compact area.\nSiPs can contain several chips—such as a specialized processor, DRAM, flash memory—combined with passive components—resistors and capacitors—all mounted on the same substrate. This means that a complete functional unit can be built in a multi-chip package, so that few external components need to be added to make it work. This is particularly valuable in space constrained environments like MP3 players and mobile phones as it reduces the complexity of the printed circuit board and overall design. Despite its benefits, this technique decreases the yield of fabrication since any defective chip in the package will result in a non-functional packaged integrated circuit, even if all other modules in that same package are functional.\nSiPs are in contrast to the common system on a chip (SoC) integrated circuit architecture which integrates components based on function into a single circuit die. An SoC will typically integrate a CPU, graphics and memory interfaces, hard-disk and USB connectivity, random-access and read-only memories, and secondary storage and/or their controllers on a single die. In comparison an SiP would connect these modules as discrete components in one or more chip carrier packages. An SiP resembles the common traditional motherboard-based PC architecture, which separates components based on function and connects them through a central interfacing circuit board. An SiP has a lower grade of integration in comparison to an SoC. Hybrid integrated circuits are somewhat similar to SiPs, however they tend to use older or less advanced technology (tend to use single layer circuit boards or substrates, not use die stacking, use wire bonding for connecting dies/devices or Small outline integrated circuit packages instead of flip chip or BGA, use Dual in-line packages, or Single in-line packages for interfacing outside the Hybrid IC instead of BGA, etc.)\nSiP technology is primarily being driven by early market trends in wearables, mobile devices and the internet of things which do not demand the high numbers of produced units as in the established consumer and business SoC market. As the internet of things becomes more of a reality and less of a vision, there is innovation going on at the system on a chip and SiP level so that microelectromechanical (MEMS) sensors can be integrated on a separate die and control the connectivity. \nSiP solutions may require multiple packaging technologies, such as flip chip, wire bonding, wafer-level packaging and more.", "Engineering,_Manufacturing": 0.9999569654, "qwen": "Yes"}
{"id": "513418", "revid": "12580852", "url": "https://en.wikipedia.org/wiki?curid=513418", "title": "Integrated circuit packaging", "text": "In electronics manufacturing, integrated circuit packaging is the final stage of semiconductor device fabrication, in which the block of semiconductor material is encapsulated in a supporting case that prevents physical damage and corrosion. The case, known as a \"package\", supports the electrical contacts which connect the device to a circuit board.\nIn the integrated circuit industry, the process is often referred to as packaging. Other names include semiconductor device assembly, assembly, encapsulation or sealing.\nThe packaging stage is followed by testing of the integrated circuit.\nThe term is sometimes confused with electronic packaging, which is the mounting and interconnecting of integrated circuits (and other components) onto printed-circuit boards.\nDesign considerations.\nElectrical.\nThe current-carrying traces that run out of the die, through the package, and into the printed circuit board (PCB) have very different electrical properties compared to on-chip signals. They require special design techniques and need much more electric power than signals confined to the chip itself. Therefore, it is important that the materials used as electrical contacts exhibit characteristics like low resistance, low capacitance and low inductance. Both the structure and materials must prioritize signal transmission properties, while minimizing any parasitic elements that could negatively affect the signal.\nControlling these characteristics is becoming increasingly important as the rest of technology begins to speed up. Packaging delays have the potential to make up almost half of a high-performance computer's delay, and this bottleneck on speed is expected to increase.\nMechanical and thermal.\nThe integrated circuit package must resist physical breakage, keep out moisture, and also provide effective heat dissipation from the chip. Moreover, for RF applications, the package is commonly required to shield electromagnetic interference, that may either degrade the circuit performance or adversely affect neighboring circuits. Finally, the package must permit interconnecting the chip to a PCB. The materials of the package are either plastic (thermoset or thermoplastic), metal (commonly Kovar) or ceramic. A common plastic used for this is epoxy-cresol-novolak (ECN). All three material types offer usable mechanical strength, moisture and heat resistance. Nevertheless, for higher-end devices, metallic and ceramic packages are commonly preferred due to their higher strength (which also supports higher pin-count designs), heat dissipation, hermetic performance, or other reasons. Generally, ceramic packages are more expensive than similar plastic packages.\nSome packages have metallic fins to enhance heat transfer, but these take up space. Larger packages also allow for more interconnecting pins.\nEconomic.\nCost is a factor in selection of integrated circuit packaging. Typically, an inexpensive plastic package can dissipate heat up to 2W, which is sufficient for many simple applications, though a similar ceramic package can dissipate up to 50W in the same scenario. As the chips inside the package get smaller and faster, they also tend to get hotter. As the subsequent need for more effective heat dissipation increases, the cost of packaging rises along with it. Generally, the smaller and more complex the package needs to be, the more expensive it is to manufacture.\nHistory.\nEarly integrated circuits were packaged in ceramic flat packs, which the military used for many years for their reliability and small size. The other type of packaging used in the 1970s, called the ICP (Integrated Circuit Package), was a ceramic package (sometime round as the transistor package), with the leads on one side, co-axially with the package axis.\nCommercial circuit packaging quickly moved to the dual in-line package (DIP), first in ceramic and later in plastic. In the 1980s VLSI pin counts exceeded the practical limit for DIP packaging, leading to pin grid array (PGA) and leadless chip carrier (LCC) packages. Surface mount packaging appeared in the early 1980s and became popular in the late 1980s, using finer lead pitch with leads formed as either gull-wing or J-lead, as exemplified by small-outline integrated circuit—a carrier which occupies an area about 30–50% less than an equivalent DIP, with a typical thickness that is 70% less.The next big innovation was the \"area array package\", which places the interconnection terminals throughout the surface area of the package, providing a greater number of connections than previous package types where only the outer perimeter is used. The first area array package was a ceramic pin grid array package. Not long after, the plastic ball grid array (BGA), another type of area array package, became one of the most commonly used packaging techniques.\nIn the late 1990s, plastic quad flat pack (PQFP) and thin small-outline packages (TSOP) replaced PGA packages as the most common for high pin count devices, though PGA packages are still often used for microprocessors. However, industry leaders Intel and AMD transitioned in the 2000s from PGA packages to land grid array (LGA) packages.\nBall grid array (BGA) packages have existed since the 1970s, but evolved into flip-chip ball grid array (FCBGA) packages in the 1990s. FCBGA packages allow for much higher pin count than any existing package types. In an FCBGA package, the die is mounted upside-down (flipped) and connects to the package balls via a substrate that is similar to a printed-circuit board rather than by wires. FCBGA packages allow an array of input-output signals (called Area-I/O) to be distributed over the entire die rather than being confined to the die periphery.\nTraces out of the die, through the package, and into the printed circuit board have very different electrical properties, compared to on-chip signals. They require special design techniques and need much more electric power than signals confined to the chip itself.\nRecent developments consist of stacking multiple dies in single package called SiP, for \"System In Package\", or three-dimensional integrated circuit. Combining multiple dies on a small substrate, often ceramic, is called an MCM, or Multi-Chip Module. The boundary between a big MCM and a small printed circuit board is sometimes blurry.\nOperations.\n\"Die attachment\" is the step during which a die is mounted and fixed to the package or support structure (header). For high-powered applications, the die is usually eutectic bonded onto the package, using e.g. gold-tin or gold-silicon solder (for good heat conduction). For low-cost, low-powered applications, the die is often glued directly onto a substrate (such as a printed wiring board) using an epoxy adhesive.\nThe following operations are performed at the packaging stage, as broken down into bonding, encapsulation, and wafer bonding steps. Note that this list is not all-inclusive and not all of these operations are performed for every package, as the process is highly dependent on the package type.", "Engineering,_Manufacturing": 0.9999850988, "qwen": "Yes"}
{"id": "927047", "revid": "38551421", "url": "https://en.wikipedia.org/wiki?curid=927047", "title": "Computer-aided industrial design", "text": "Computer Aided Industrial Design (CAID) is a subset of computer-aided design (CAD) software that can assist in creating the look-and-feel or industrial design aspects of a product in development.\nCAID programs tend to provide designers with improved freedom of creativity compared to typical CAD tools. However a typical workflow may follow a simple design methodology as follows:\nThe end result is generally a 3D model that represents the main intent of the designer had in mind for the physical product. Such models can then be saved in formats for more convenient exchange with others (such as OBJ for virtual viewing in 3D graphics programs) or manufacturing (such a STL to create a real-life model via a rapid prototyping machine). CAID helps the designer focus on the technical aspect of the design methodology rather than the sketching and modelling aspects, contributing to the selection of a better product proposal in less time. When product pre-requisites and parameters have been more completely defined, output from the CAID software can be imported into a CAD program for pre-production testing, adjustment, and generation of technical drawings and manufacturing data such as CNC tool-paths.\nCAID is far more conceptual and less technically focused than CAD. CAID programs tend to offer more tools that allow a designer to freely express themselves with more organic shapes and complex curves, whilst CAD software tends to be more focused on tools for the simple curves and straight lines more suitable for easy manufacturing.\nCAD implementations have evolved dramatically since initial 3D offerings in the 1970s, which were typically limited to producing drawings similar to hand-drafted output. Advances in programming and computer hardware,[21][22] notably solid modelling in the 1980s, have allowed more versatile applications of computers in design activities.", "Engineering,_Manufacturing": 0.9999155998, "qwen": "Yes"}
{"id": "5518742", "revid": "589223", "url": "https://en.wikipedia.org/wiki?curid=5518742", "title": "Plastic extrusion", "text": "Plastics extrusion is a high-volume manufacturing process in which raw plastic is melted and formed into a continuous profile. Extrusion produces items such as pipe/tubing, weatherstripping, fencing, deck railings, window frames, plastic films and sheeting, thermoplastic coatings, and wire insulation.\nThis process starts by feeding plastic material (pellets, granules, flakes or powders) from a hopper into the barrel of the extruder. The material is gradually melted by the mechanical energy generated by turning screws and by heaters arranged along the barrel. The molten polymer is then forced into a die, which shapes the polymer into a shape that hardens during cooling.\nHistory.\nThe first precursors to the modern extruder were developed in the early 19th century. In 1820, Thomas Hancock invented a rubber \"masticator\" designed to reclaim processed rubber scraps, and in 1836 Edwin Chaffee developed a two-roller machine to mix additives into rubber. The first thermoplastic extrusion was in 1935 by Paul Troester and his wife Ashley Gershoff in Hamburg, Germany. Shortly after, Roberto Colombo of LMP developed the first twin screw extruders in Italy.\nProcess.\nIn the extrusion of plastics, the raw compound material is commonly in the form of nurdles (small beads, often called resin) that are gravity fed from a top mounted hopper into the barrel of the extruder. Additives such as colorants and UV inhibitors (in either liquid or pellet form) are often used and can be mixed into the resin prior to arriving at the hopper. The process has much in common with plastic injection molding from the point of the extruder technology, although it differs in that it is usually a continuous process. While pultrusion can offer many similar profiles in continuous lengths, usually with added reinforcing, this is achieved by pulling the finished product out of a die instead of extruding the polymer melt through a die.\nThe material enters through the feed throat (an opening near the rear of the barrel) and comes into contact with the screw. The rotating screw (normally turning at e.g. 120 rpm) forces the plastic beads forward into the heated barrel. The desired extrusion temperature is rarely equal to the set temperature of the barrel due to viscous heating and other effects. In most processes, a heating profile is set for the barrel in which three or more independent PID-controlled heater zones gradually increase the temperature of the barrel from the rear (where the plastic enters) to the front. This allows the plastic beads to melt gradually as they are pushed through the barrel and lowers the risk of overheating which may cause polymer degradation.\nExtra heat is contributed by the intense pressure and friction taking place inside the barrel. In fact, if an extrusion line is running certain materials fast enough, the heaters can be shut off and the melt temperature maintained by pressure and friction alone inside the barrel. In most extruders, cooling fans are present to keep the temperature below a set value if too much heat is generated. If forced air cooling proves insufficient then cast-in cooling jackets are employed.\nAt the front of the barrel, the molten plastic leaves the screw and travels through a screen pack to remove any contaminants in the melt. The screens are reinforced by a breaker plate (a thick metal puck with many holes drilled through it) since the pressure at this point can exceed 5,000 psi (34 MPa). The screen pack/breaker plate assembly also serves to create back pressure in the barrel. Back pressure is required for uniform melting and proper mixing of the polymer, and how much pressure is generated can be \"tweaked\" by varying screen pack composition (the number of screens, their wire weave size, and other parameters). This breaker plate and screen pack combination also eliminates the \"rotational memory\" of the molten plastic and creates instead, \"longitudinal memory\".\nAfter passing through the breaker plate molten plastic enters the die. The die is what gives the final product its profile and must be designed so that the molten plastic evenly flows from a cylindrical profile, to the product's profile shape. Uneven flow at this stage can produce a product with unwanted residual stresses at certain points in the profile which can cause warping upon cooling. A wide variety of shapes can be created, restricted to continuous profiles.\nThe product must now be cooled and this is usually achieved by pulling the extrudate through a water bath. Plastics are very good thermal insulators and are therefore difficult to cool quickly. Compared to steel, plastic conducts its heat away 2,000 times more slowly. In a tube or pipe extrusion line, a sealed water bath is acted upon by a carefully controlled vacuum to keep the newly formed and still molten tube or pipe from collapsing. For products such as plastic sheeting, the cooling is achieved by pulling through a set of cooling rolls. For films and very thin sheeting, air cooling can be effective as an initial cooling stage, as in blown film extrusion.\nPlastic extruders are also extensively used to reprocess recycled plastic waste or other raw materials after cleaning, sorting and/or blending. This material is commonly extruded into filaments suitable for chopping into the bead or pellet stock to use as a precursor for further processing.\nScrew design.\nThere are five possible zones in a thermoplastic screw. Since terminology is not standardized in the industry, different names may refer to these zones. Different types of polymer will have differing screw designs, some not incorporating all of the possible zones.\nMost screws have these three zones:\nIn addition, a vented (two-stage) screw has:\nOften screw length is referenced to its diameter as L:D ratio. For instance, a diameter screw at 24:1 will be 144 inches (12 ft) long, and at 32:1 it is 192 inches (16 ft) long. An L:D ratio of 25:1 is common, but some machines go up to 40:1 for more mixing and more output at the same screw diameter. Two-stage (vented) screws are typically 36:1 to account for the two extra zones.\nEach zone is equipped with one or more thermocouples or RTDs in the barrel wall for temperature control. The \"temperature profile\" i.e., the temperature of each zone is very important to the quality and characteristics of the final extrudate.\nTypical extrusion materials.\nTypical plastic materials that are used in extrusion include but are not limited to: polyethylene (PE), polypropylene, polyacetal, acrylic, nylon (polyamides), polystyrene, polyvinyl chloride (PVC), acrylonitrile butadiene styrene (ABS) and polycarbonate.\nDie types.\nThere are a variety of dies used in plastics extrusion. While there can be significant differences between die types and complexity, all dies allow for the continuous extrusion of polymer melt, as opposed to non-continuous processing such as injection molding.\nBlown film extrusion.\nThe manufacture of plastic film for products such as food packages, shopping bags, and continuous sheeting is achieved using a blown film line.\nThis process is the same as a regular extrusion process up until the die. There are three main types of dies used in this process: annular (or crosshead), spider, and spiral. Annular dies are the simplest, and rely on the polymer melt channeling around the entire cross section of the die before exiting the die; this can result in uneven flow. Spider dies consist of a central mandrel attached to the outer die ring via a number of \"legs\"; while flow is more symmetrical than in annular dies, a number of weld lines are produced which weaken the film. Spiral dies remove the issue of weld lines and asymmetrical flow, but are by far the most complex.\nThe melt is cooled somewhat before leaving the die to yield a weak semi-solid tube. This tube's diameter is rapidly expanded via air pressure, and the tube is drawn upwards with rollers, stretching the plastic in both the transverse and draw directions. The drawing and blowing cause the film to be thinner than the extruded tube, and also preferentially aligns the polymer molecular chains in the direction that sees the most plastic strain. If the film is drawn more than it is blown (the final tube diameter is close to the extruded diameter) the polymer molecules will be highly aligned with the draw direction, making a film that is strong in that direction, but weak in the transverse direction. A film that has significantly larger diameter than the extruded diameter will have more strength in the transverse direction, but less in the draw direction.\nIn the case of polyethylene and other semi-crystalline polymers, as the film cools it crystallizes at what is known as the frost line. As the film continues to cool, it is drawn through several sets of nip rollers to flatten it into lay-flat tubing, which can then be spooled or slit into two or more rolls of sheeting.\nSheet/film extrusion.\nSheet/film extrusion is used to extrude plastic sheets or films that are too thick to be blown. There are two types of dies used: T-shaped and coat hanger. The purpose of these dies is to reorient and guide the flow of polymer melt from a single round output from the extruder to a thin, flat planar flow. In both die types ensure constant, uniform flow across the entire cross sectional area of the die. Cooling is typically by pulling through a set of cooling rolls (calender or \"chill\" rolls). In sheet extrusion, these rolls not only deliver the necessary cooling but also determine sheet thickness and surface texture. Often co-extrusion is used to apply one or more layers on top of a base material to obtain specific properties such as UV-absorption, texture, oxygen permeation resistance, or energy reflection.\nA common post-extrusion process for plastic sheet stock is thermoforming, where the sheet is heated until soft (plastic), and formed via a mold into a new shape. When vacuum is used, this is often described as vacuum forming. Orientation (i.e. ability/ available density of the sheet to be drawn to the mold which can vary in depths from 1 to 36 inches typically) is highly important and greatly affects forming cycle times for most plastics.\nTubing extrusion.\nExtruded tubing, such as PVC pipes, is manufactured using very similar dies as used in blown film extrusion. Positive pressure can be applied to the internal cavities through the pin, or negative pressure can be applied to the outside diameter using a vacuum sizer to ensure correct final dimensions. Additional lumens or holes may be introduced by adding the appropriate inner mandrels to the die.\nMulti-layer tubing applications are also ever present within the automotive industry, plumbing & heating industry and packaging industry.\nOver jacketing extrusion.\nOver jacketing extrusion allows for the application of an outer layer of plastic onto an existing wire or cable. This is the typical process for insulating wires.\nThere are two different types of die tooling used for coating over a wire, tubing (or jacketing) and pressure. In jacketing tooling, the polymer melt does not touch the inner wire until immediately before the die lips. In pressure tooling, the melt contacts the inner wire long before it reaches the die lips; this is done at a high pressure to ensure good adhesion of the melt. If intimate contact or adhesion is required between the new layer and existing wire, pressure tooling is used. If adhesion is not desired/necessary, jacketing tooling is used instead.\nCoextrusion.\nCoextrusion is the extrusion of multiple layers of material simultaneously. This type of extrusion utilizes two or more extruders to melt and deliver a steady volumetric throughput of different viscous plastics to a single extrusion head (die) which will extrude the materials in the desired form. This technology is used on any of the processes described above (blown film, overjacketing, tubing, sheet). The layer thicknesses are controlled by the relative speeds and sizes of the individual extruders delivering the materials.\nIn many real-world scenarios, a single polymer cannot meet all the demands of an application. Compound extrusion allows a blended material to be extruded, but coextrusion retains the separate materials as different layers in the extruded product, allowing appropriate placement of materials with differing properties such as oxygen permeability, strength, stiffness, and wear resistance.\nExtrusion coating.\nExtrusion coating is using a blown or cast film process to coat an additional layer onto an existing rollstock of paper, foil or film. For example, this process can be used to improve the characteristics of paper by coating it with polyethylene to make it more resistant to water. The extruded layer can also be used as an adhesive to bring two other materials together. Tetrapak is a commercial example of this process.\nCompound extrusions.\nCompounding extrusion is a process that mixes one or more polymers with additives to give plastic compounds. The feeds may be pellets, powder and/or liquids, but the product is usually in pellet form, to be used in other plastic-forming processes such as extrusion and injection molding. As with traditional extrusion, there is a wide range in machine sizes depending on application and desired throughput. While either single- or double-screw extruders may be used in traditional extrusion, the necessity of adequate mixing in compounding extrusion makes twin-screw extruders all but mandatory.\nTypes of extruder.\nThere are two sub-types of twin screw extruders: co-rotating and counter-rotating. This nomenclature refers to the relative direction each screw spins compared to the other. In co-rotation mode, both screws spin either clockwise or counter clockwise; in counter-rotation, one screw spins clockwise while the other spins counter clockwise. It has been shown that, for a given cross sectional area and degree of overlap (intermeshing), axial velocity and degree of mixing is higher in co-rotating twin extruders. However, pressure buildup is higher in counter-rotating extruders. The screw design is commonly modular in that various conveying and mixing elements are arranged on the shafts to allow for rapid reconfiguration for a process change or replacement of individual components due to wear or corrosive damage. The machine sizes range from as small as 12 mm to as large as 380mm [12- Polymer Mixing by James White, pages 129-140]\nAdvantages.\nA great advantage of extrusion is that profiles such as pipes can be made to any length. If the material is sufficiently flexible, pipes can be made at long lengths even coiling on a reel. Another advantage is the extrusion of pipes with integrated coupler including rubber seal.", "Engineering,_Manufacturing": 0.9999976158, "qwen": "Yes"}
{"id": "5534558", "revid": "1893804", "url": "https://en.wikipedia.org/wiki?curid=5534558", "title": "Design for assembly", "text": "Design for assembly (DFA) is a process by which products are designed with ease of assembly in mind. If a product contains fewer parts it will take less time to assemble, thereby reducing assembly costs. In addition, if the parts are provided with features which make it easier to grasp, move, orient and insert them, this will also reduce assembly time and assembly costs. The reduction of the number of parts in an assembly has the added benefit of generally reducing the total cost of parts in the assembly. This is usually where the major cost benefits of the application of design for assembly occur. Critics of DFA from within industry argue that DFA/DFM is simply a new term for something that has existed as long as manufacturing itself, and is otherwise known as engineering design.\nApproaches.\nDesign for assembly can take different forms. In the 1960s and 1970s various rules and recommendations were proposed in order to help designers consider assembly problems during the design process. Many of these rules and recommendations were presented together with practical examples showing how assembly difficulty could be improved. However, it was not until the 1970s that numerical evaluation methods were developed to allow design for assembly studies to be carried out on existing and proposed designs.\nThe first evaluation method was developed at Hitachi and was called the Assembly Evaluation Method (AEM). This method is based on the principle of \"one motion for one part.\" For more complicated motions, a point-loss standard is used and the ease of assembly of the whole product is evaluated by subtracting points lost. The method was originally developed in order to rate assemblies for ease of automatic assembly.\nStarting in 1977, Geoff Boothroyd, supported by an NSF grant at the University of Massachusetts Amherst, developed the Design for Assembly method (DFA), which could be used to estimate the time for manual assembly of a product and the cost of assembling the product on an automatic assembly machine. Recognizing that the most important factor in reducing assembly costs was the minimization of the number of separate parts in a product, he introduced three simple criteria which could be used to determine theoretically whether any of the parts in the product could be eliminated or combined with other parts. These criteria, together with tables relating assembly time to various design factors influencing part grasping, orientation and insertion, could be used to estimate total assembly time and to rate the quality of a product design from an assembly viewpoint. For automatic assembly, tables of factors could be used to estimate the cost of automatic feeding and orienting and automatic insertion of the parts on an assembly machine.\nIn the 1980s and 1990s, variations of the AEM and DFA methods have been proposed, namely: the GE Hitachi method which is based on the AEM and DFA; the Lucas method, the Westinghouse method and several others which were based on the original DFA method. All methods are now referred to as \"design for assembly\" methods.\nImplementation.\nMost products are assembled manually and the original DFA method for manual assembly is the most widely used method and has had the greatest industrial impact throughout the world.\nThe DFA method, like the AEM method, was originally made available in the form of a handbook where the user would enter data on worksheets to obtain a rating for the ease of assembly of a product. Starting in 1981, Geoffrey Boothroyd and Peter Dewhurst developed a computerized version of the DFA method which allowed its implementation in a broad range of companies. For this work they were presented with many awards including the National Medal of Technology. There are many published examples of significant savings obtained through the application of DFA. For example, in 1981, Sidney Liebson, manager of manufacturing engineering for Xerox, estimated that his company would save hundreds of millions of dollars through the application of DFA. In 1988, Ford Motor Company credited the software with overall savings approaching $1 billion. In many companies DFA is a corporate requirement and DFA software is continually being adopted by companies attempting to obtain greater control over their manufacturing costs. There are many key principles in design for assembly.\nNotable examples.\nTwo notable examples of good design for assembly are the Sony Walkman and the Swatch watch. Both were designed for fully automated assembly. The Walkman line was designed for \"vertical assembly\", in which parts are inserted in straight-down moves only. The Sony SMART assembly system, used to assemble Walkman-type products, is a robotic system for assembling small devices designed for vertical assembly. \nThe IBM Proprinter used design for automated assembly (DFAA) rules. These DFAA rules help design a product that can be assembled automatically by robots, but they are useful even with products assembled by manual assembly.\nFurther information.\nFor more information on Design for Assembly and the subject of Design for Manufacture and Assembly see:", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "4425696", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=4425696", "title": "Rack rail", "text": "A rack rail, or rack strip, is used to mount rackable electronic hardware and 19-inch rack mount accessories within a 19-inch rack. Within a rack a minimum of two rack rails are required to mount equipment. The height of rack rail is determined by the number of rack units required for mounting the equipment.\nThe design of racks and rack rails is specified in ECIA - EIA/ECA-310.\nEach rack unit (U) is equivalent to . Most rack rail is in sizes from 2 units high  to 54 units high .\nTypes.\nRack Rail comes in two different commonly used forms. Tapped/threaded rack rail has round holes tapped for 10-32 UNF or 10-24 UNC screws. The other common form of rack rail is square hole rack strip which has square holes for captive nuts, available tapped for various different screw threads, that are clipped into the holes as needed to mount equipment.\nIn both cases, rack screws and washers are required to mount rack mount equipment to the rack rail. The size and strength of rack rail is determined by its application. Increased thickness of steel results in stronger rack rail and varieties of rack rail can be found such as double angle and single angle rack rail.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "51081166", "revid": "36112485", "url": "https://en.wikipedia.org/wiki?curid=51081166", "title": "Hugon, The Mighty", "text": "Hugon, The Mighty is a lost 1918 silent film Northwoods drama directed by Rollin S. Sturgeon and starring Monroe Salisbury. It was produced by Bluebird Photoplays and released through Universal Film Manufacturing Company.", "Engineering,_Manufacturing": 0.6451840401, "qwen": "Yes"}
{"id": "872694", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=872694", "title": "Autobike", "text": "An autobike or automatically geared bicycle is a bicycle with an automatic transmission that shifts gears without intervention from the rider.\nHistory.\nIn 2011 the company Autobike was founded by Mark Simpson. In the company applied for a patent on a system which automatically changes gears on a bicycle, and they started selling their Voyage line of bicycles. The original Autobike was equipped with a system of centrifugal weights on the rear wheel with a rear derailleur attached to them. When the rider started pedaling it would cause the weights to spin outwards, which shifted the derailleur to a higher gear. When the rider stops pedaling and the bike comes to a stop, the weights would return to the centre position, shifting the bike into its lowest gear so it is easier to get started again. Autobike went bankrupt.\nThe current Autobike uses three main components in its automatic transmission. In order to provide the system with power, the front wheel uses a hub dynamo to generate electricity. Wires connect the dynamo through the frame to the bottom bracket area where it joins a small onboard computer with sensors that detect the rider's speed and cadence. The computer uses this information to actuate a motorised shifter mounted on the rear wheel's hub gear to change the gear ratio. The rear hub used is the Nuvinci N360 CVP which is a continuously variable transmission using a planetary gear system that can be shifted smoothly at any time, under any load.", "Engineering,_Manufacturing": 0.999933362, "qwen": "Yes"}
{"id": "874361", "revid": "31772205", "url": "https://en.wikipedia.org/wiki?curid=874361", "title": "Bugatti EB 218", "text": "The Bugatti EB 218 saloon is the second concept car presented by Bugatti under the ownership of the Volkswagen Auto Group. The EB 218 was designed by Giorgetto Giugiaro, who also designed the EB 112, the car's predecessor and the EB 118, the car's 2-door variant. The EB 218 can be considered as an update of the EB 112, a concept saloon introduced by Bugatti Automobili SpA in 1993. The EB 218 features Volkswagen's unconventional W18 engine and permanent four-wheel drive borrowed from the Lamborghini Diablo VT.\nDesign.\nBugatti commissioned Giorgetto Giugiaro of Italdesign to update the EB 112 concept that he designed for Bugatti Automobili SpA in 1993. The EB218's wheelbase measures and it has a total length of . This makes the EB 218 longer that the EB 112 by . The most notable visual differences between the EB 218 and the EB 112 is a redesigned hood, bumpers and lights. The overall design is far less controversial than the EB 112's \"Droopy hatchback-saloon\" design and has a much more of a typical saloon shape rather than the EB 112's hatchback shape. The interior design is very simple yet extremely luxurious, with beige leather seats and a large wooden dashboard which manages to keep all the instruments and vents \"composed\". The EB 218 draws inspiration from the classic Type 101 Guillore.\nDebut.\nBugatti introduced the EB 218 at the 1999 Geneva Motor Show, one year after its 2-door counterpart was introduced at the 1998 Paris Auto Show.\nPowertrain.\nThe EB 218 uses the same W18 engine and permanent four wheel drive powertrain that debuted in the 1998 EB 118. The same technology was used in the 1999 18/3 Chiron concept car.\nPower comes from a Volkswagen-designed, and , W18 engine. This engine design was extremely unconventional due to the unusual firing order of the engine. The EB 218 W18 engine is composed of three banks of six cylinders with a sixty degree offset between each cylinder bank. In contrast, the W16 engine in Bugatti's (Under Volkswagen ownership) first production car, the 2005 Veyron EB 16.4 features four banks of four cylinders. The EB 218 has the permanent all-wheel drive taken from the Lamborghini Diablo VT sports car.", "Engineering,_Manufacturing": 0.9955968857, "qwen": "Yes"}
{"id": "874838", "revid": "39191556", "url": "https://en.wikipedia.org/wiki?curid=874838", "title": "Desoldering", "text": "In electronics, desoldering is the removal of solder and components from a circuit board for troubleshooting, repair, replacement, and salvage.\nTools.\nDesoldering tools and materials include the following:\nTerminology is not totally standardised. Anything with a base unit with provision to maintain a stable temperature, pump air in either direction, etc., is often called a \"station\" (preceded by rework, soldering, desoldering, hot air); one, or sometimes more, tools may be connected to a station, e.g., a rework station may accommodate a soldering iron and hot air head. A soldering iron with a hollow tip and a spring-, bulb-, or electrically-operated suction pump may be called a . Terms such as \"suction pen\" may be used; the meaning is usually clear from the context.\nPumps.\nElectrically operated pumps are used for several purposes in conjunction with a hand-held head connected by a tube.\nSuction pumps are used to suck away molten solder, leaving previously joined terminals disconnected. They are primarily used to release through-hole connections from a PCB. The desoldering head must be designed so that the extracted solder does not solidify so as to obstruct it, or enter the pump, and can be removed and discarded easily. It is not possible to remove a multi-pin part by melting solder on the pins sequentially, as one joint will solidify as the next is melted; pumps and solder wick are among methods to remove solder from all joints, leaving the part free to be removed.\nSuction pumps are also used with a suction head appropriate for each part to pick up and remove tiny surface mount devices once solder has melted, and to place parts.\nHot air pumps blow air hot enough to melt all the solder around a small surface mounted part, and can be used for soldering parts in place, and for desoldering followed by removal before the solder solidifies by a vacuum pump or with tweezers. Hot air has a tendency to oxidise metals; a non-oxidising gas, usually nitrogen, can be used instead of air, at increased cost of equipment and consumables.\nDesoldering pump.\nA desoldering pump, colloquially known as a solder sucker, is a manually-operated device which is used to remove solder from a printed circuit board. There are two types: the \"plunger\" style and \"bulb\" style. (An electrically-operated pump for this purpose would usually be called a vacuum pump.)\nThe plunger type has a cylinder with a spring-loaded piston which is pushed down and locks into place. When triggered by pressing a button, the piston springs up, creating suction that sucks the solder off the soldered connection. The bulb type creates suction by squeezing and releasing a rubber bulb.\nThe pump is applied to a heated solder connection, then operated to suck the solder away.\nDesoldering braid.\nDesoldering braid, also known as desoldering wick or solder wick, is finely braided 18 to 42 AWG copper wire coated with rosin flux, usually supplied on a roll.\nThe end of a length of braid is placed over the soldered connections of a component being removed. The connections are heated with a soldering iron until the solder melts and is wicked into the braid by capillary action. The braid is removed while the solder is still molten, its used section cut off and discarded when cool. Short lengths of cut braid will prevent heat being carried away by the braid instead of heating the joint.\nTechnique.\nDesoldering requires application of heat to the solder joint and removing the molten solder so that the joint may be separated. Desoldering may be required to replace a defective component, to alter an existing circuit, or to salvage components for re-use. Use of too high a temperature or heating for too long may damage components or destroy the bond between a printed circuit trace and the board substrate. Techniques are different for through-hole and surface-mounted components.\nThrough-hole.\nA component with one or two connections to the PCB can usually be removed by heating one joint, pulling out an end of the component while the solder is molten (bending the other lead to do so), and repeating for the second joint. Solder filling the hole can be removed with a pump or with a pointed object made of a material which solder does not wet, such as stainless steel or wood.\nIf a multi-pin component need not be salvaged, it is often possible to cut the pins, then remove the residual ends one by one.\nComponents with more connections cannot be removed intact in the way described above unless the wire leads are long and flexible enough to be pulled out one by one. For a component such as a Dual-Inline Package (DIP), the pins are too short to pull out, and solder melted on one joint will solidify before another can be melted. A technique sometimes used is the use of a large soldering-iron tip designed to melt the solder on all pins at once; different tips are required for different packages. The component is removed while the solder is molten, most easily by a spring-loaded puller attached to it before heating.\nOtherwise all joints must be freed from solder before the component can be removed. Each joint must be heated and the solder removed from it while molten using a vacuum pump, manual desoldering pump, or desoldering braid.\nFor through-hole mounted devices on double-sided or multi-layer boards, special care must be taken not to remove the via connecting the layers, as this will ruin the entire board. Hard pulling on a lead which is not entirely free of solder (or with solder not thoroughly molten in the case of a soldering iron tip heating all pins) may pull out a via.\nTo remove and recover all components, both through-hole and surface-mount, from a board which itself is usually no longer needed, a flame or hot air gun can be used to rapidly heat all parts so they can be pulled off. Parts may be damaged, and toxic fumes emitted, if excessive temperature or prolonged heating is used.\nSurface mount.\nIf they do not need to be re-used, some surface-mount components can be removed by cutting their leads and desoldering the remnants with a soldering iron.\nOtherwise, surface-mount components must be removed by heating the entire component to a temperature sufficient to melt the solder used, but not high or prolonged enough to damage the component. For most purposes, a temperature not exceeding for a time not exceeding 10 seconds is acceptable.\nThe entire board may be preheated to a temperature that all components can withstand indefinitely. Then localised heat is applied to the component to remove, with less heating required than from cold. Most frequently, a hot air (or hot gas) gun, with a nozzle of appropriate size and shape, is used to heat the component, with nearby components shielded from the heat if necessary, followed by removal with tweezers or a vacuum tool. Removal of multi-pin components with a soldering iron and solder removal tools is impractical, as the solder between the component and the pads remains in place, unlike solder which can be removed from a hole.\nHot air (or gas) may be applied with tools ranging from some portable gas soldering irons such as the Weller Portasol Professional which can be fitted with a narrow hot-air nozzle, set to a temperature not controlled but approximately correct, to an industrial rework station with many facilities including hot-gas blowing, vacuum part holding, soldering iron head, and nozzles and fitting specific to particular component packages.\nQuad flat packages.\nQuad Flat Package (QFP) chips have thin leads closely packed together protruding from the four sides of the integrated circuit (IC); usually a square IC. Removal of these chips can be problematic as it is impossible to heat all of the leads at once with a standard soldering iron. It is possible to remove them with the use of a razor blade or a high-rpm craft tool, simply by cutting off the leads. The stubs are then easy to melt off and clean with a soldering iron. Obviously this technique entails the destruction of the IC. Another method is to use a heat gun or pencil butane torch and heat up a corner, and gently pry it off, working the torch down the leads. This method often leads to traces getting lifted off the PCB where a lead did not get heated enough to cause the solder to flow.\nSeveral vendors offer systems that use heat shields to concentrate hot air where it needs to be, protecting nearby components and avoiding damage to the board or the QFP. The extractor uses a spring system that gently pulls the IC upward when the liquid stage of solder has been reached. The IC is held by a vacuum nozzle similar to the ones used in pick & place machines. This system prevents damage to the pads on the PCB, the IC, avoids overheating surrounding components and blowing them off and also reduces the risk of operator error when using tweezers or other tools that can damage the PCB or IC.\nAnother way to remove these devices is to use Field's metal, an alloy which melts at around 140 °F (62 °C), lower than the boiling point of water. The metal is melted into the solder joints of the device, where it remains liquid even once cooled down to room temperature, and the chip can simply be lifted off the board. This has the advantage of not damaging the PCB or the IC, although the solder joints must be carefully cleaned of any remaining Field's metal to maintain solder joint strength after resoldering.", "Engineering,_Manufacturing": 0.998483479, "qwen": "Yes"}
{"id": "11414813", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=11414813", "title": "Supply chain responsiveness matrix", "text": "A supply chain responsiveness matrix is a tool that is used to analyze inventory and lead time within an organization. The matrix is one of a number of value stream mapping tools. The matrix is represented by showing lead time along the x-axis and inventory along the y-axis. The result shows where slow moving stock resides.", "Engineering,_Manufacturing": 0.9992880225, "qwen": "Yes"}
{"id": "3155665", "revid": "7852030", "url": "https://en.wikipedia.org/wiki?curid=3155665", "title": "Antiwear additive", "text": "AW additives, or antiwear additives, are additives for lubricants to prevent metal-to-metal contact between parts of gears.\nEP additives are used in applications such as gearboxes, while AW additives are used with lighter loads such as bushings.\nDetails.\nSome popular AW additives are:\nSome formulations use colloidal PTFE (Teflon), but its efficiency is controversial.\nMany AW additives function as EP additives, for example organophosphates or sulfur compounds. The mechanism of function of TCP and ZDDP is explained in EP additives.\nUnder extreme pressure conditions, the performance of AW additives becomes insufficient and designated EP additives are required.", "Engineering,_Manufacturing": 0.9999988079, "qwen": "Yes"}
{"id": "51500017", "revid": "2051880", "url": "https://en.wikipedia.org/wiki?curid=51500017", "title": "Design for additive manufacturing", "text": "Design for additive manufacturing (DfAM or DFAM) is design for manufacturability as applied to additive manufacturing (AM). It is a general type of design methods or tools whereby functional performance and/or other key product life-cycle considerations such as manufacturability, reliability, and cost can be optimized subjected to the capabilities of additive manufacturing technologies.\nThis concept emerges due to the enormous design freedom provided by AM technologies. To take full advantages of unique capabilities from AM processes, DfAM methods or tools are needed. Typical DfAM methods or tools includes topology optimization, design for multiscale structures (lattice or cellular structures), multi-material design, mass customization, part consolidation, and other design methods which can make use of AM-enabled features.\nDfAM is not always separate from broader DFM, as the making of many objects can involve both additive and subtractive steps. Nonetheless, the name \"DfAM\" has value because it focuses attention on the way that commercializing AM in production roles is not just a matter of figuring out how to switch existing parts from subtractive to additive. Rather, it is about redesigning entire objects (assemblies, subsystems) in view of the newfound availability of advanced AM. That is, it involves redesigning them because their entire earlier design—including even how, why, and at which places they were originally divided into discrete parts—was conceived within the constraints of a world where advanced AM did not yet exist. Thus instead of just modifying an existing part design to allow it to be made additively, full-fledged DfAM involves things like reimagining the overall object such that it has fewer parts or a new set of parts with substantially different boundaries and connections. The object thus may no longer be an assembly at all, or it may be an assembly with many fewer parts. Many examples of such deep-rooted practical impact of DfAM have been emerging in the 2010s, as AM greatly broadens its commercialization. For example, in 2017, GE Aviation revealed that it had used DfAM to create a helicopter engine with 16 parts instead of 900, with great potential impact on reducing the complexity of supply chains. It is this radical rethinking aspect that has led to themes such as that \"DfAM requires 'enterprise-level disruption'.\" In other words, the disruptive innovation that AM can allow can logically extend throughout the enterprise and its supply chain, not just change the layout on a machine shop floor.\nDfAM involves both broad themes (which apply to many AM processes) and optimizations specific to a particular AM process. For example, DFM analysis for stereolithography maximizes DfAM for that modality.\nBackground.\nAdditive manufacturing is defined as a material joining process, whereby a product can be directly fabricated from its 3D model, usually layer upon layer. Comparing to traditional manufacturing technologies such as CNC machining or casting, AM processes have several unique capabilities. It enables the fabrication of parts with a complex shape as well as complex material distribution. These unique capabilities significantly enlarge the design freedom for designers. However, they also bring a big challenge. Traditional Design for manufacturing (DFM) rules or guidelines deeply rooted in designers’ mind and severely restrict designers to further improve product functional performance by taking advantages of these unique capabilities brought by AM processes. Moreover, traditional feature-based CAD tools are also difficult to deal with irregular geometry for the improvement of functional performance. To solve these issues, design methods or tools are needed to help designers to take full advantages of design freedom provide by AM processes. These design methods or tools can be categorized as Design for Additive Manufacturing.\nMethods.\nTopology optimization.\nTopology optimization is a type of structural optimization technique which can optimize material layout within a given design space. Compared to other typical structural optimization techniques, such as size optimization or shape optimization, topology optimization can update both shape and topology of a part. However, the complex optimized shapes obtained from topology optimization are always difficult to handle for traditional manufacturing processes such as CNC machining. To solve this issue, additive manufacturing processes can be applied to fabricate topology optimization result. However, it should be noticed, some manufacturing constraints such as minimal feature size also need to be considered during the topology optimization process. Since the topology optimization can help designers to get an optimal complex geometry for additive manufacturing, this technique can be considered one of DfAM methods.\nMultiscale structure design.\nDue to the unique capabilities of AM processes, parts with multiscale complexities can be realized. This provides a great design freedom for designers to use cellular structures or lattice structures on micro or meso-scales for the preferred properties. For example, in the aerospace field, lattice structures fabricated by AM process can be used for weight reduction. In the bio-medical field, bio-implant made of lattice or cellular structures can enhance osseointegration.\nMulti-material design.\nParts with multi-material or complex material distribution can be achieved by additive manufacturing processes. To help designers to take use of this advantage, several design and simulation methods has been proposed to support design a part with multiple materials or Functionally Graded Materials . These design methods also bring a challenge to traditional CAD system. Most of them can only deal with homogeneous materials now.\nDesign for mass customization.\nSince additive manufacturing can directly fabricate parts from products’ digital model, it significantly reduces the cost and leading time of producing customized products. Thus, how to rapidly generate customized parts becomes a central issue for mass customization. Several design methods have been proposed to help designers or users to obtain the customized product in an easy way. These methods or tools can also be considered as the DfAM methods.\nParts consolidation.\nDue to the constraints of traditional manufacturing methods, some complex components are usually separated into several parts for the ease of manufacturing as well as assembly. This situation has been changed by the using of additive manufacturing technologies. Some case studies have been done to shows some parts in the original design can be consolidated into one complex part and fabricated by additive manufacturing processes. This redesigning process can be called as parts consolidation. The research shows parts consolidation will not only reduce part count, it can also improve the product functional performance. The design methods which can guide designers to do part consolidation can also be regarded as a type of DfAM methods.\nLattice structures.\nLattice structures is a type of cellular structures (i.e. open). These structures were previously difficult to manufacture, hence was not widely used. Thanks to the free-form manufacturing capability of additive manufacturing technology, it is now possible to design and manufacture complex forms. Lattice structures have high strength and low mass mechanical properties and multifunctionality. These structures can be found in parts in the aerospace and biomedical industries. It has been observed that these lattice structures mimic atomic crystal lattice, where the nodes and struts represent atoms and atomic bonds, respectively, and termed as meta-crystals. They obey the metallurgical hardening principles (grain boundary strengthening, precipitate hardening etc.) when undergoing deformation. It has been further reported that the yield strength and ductility of the struts (meta-atomic bonds) can be increased drastically by taking advantage of the non-equilibrium solidification phenomenon in Additive Manufacturing, thus increasing the performance of the bulk structures.\nThermal issues in design.\nFor AM processes that use heat to fuse powder or feedstock, process consistency and part quality are strongly influenced by the temperature history inside the part during manufacture, especially for metal AM.\nThermal modelling can be used to inform part design and the choice of process parameters for manufacture, in place of expensive empirical testing.\nOptimal design for additive manufacturing.\nAdditively manufactured metallic structures with the same (macroscopic) shape and size but fabricated by different process parameters have strikingly different microstructures and hence mechanical properties. The abundant and highly flexible AM process parameters substantially influence the AM microstructures. Therefore, in principle, one could simultaneously 3D-print the (macro-)structure as well as the desirable microstructure depending on the expected performance of the specialized AM component under the known service load. In this context, multi-scale and multi-physics integrated computational materials engineering (ICME) for computational linkage of process-(micro)structure-properties-performance (PSPP) chain can be used to efficiently search an AM design subspace for the optimum point with respect to the performance of the AM structure under the known service load. The comprehensive design space of metal AM is boundless and high dimensional, which includes all the possible combinations of alloy compositions, process parameters and structural geometries. However, always a constrained subset of the design space (design subspace) is under consideration. The performance, as the design objective, depending on the thermo-chemo-mechanical service load, may include multiple functional aspects, such as specific energy absorption capacity, fatigue life/strength, high temperature strength, creep resistance, erosion/wear resistance and/or corrosion resistance. It is hypothesized that the optimal design approach is essential for unraveling the full potential of metal AM technologies and thus their widespread adoption for production of structurally critical load-bearing components.", "Engineering,_Manufacturing": 1.0000083447, "qwen": "Yes"}
{"id": "72172440", "revid": "5846", "url": "https://en.wikipedia.org/wiki?curid=72172440", "title": "Barış Tan", "text": "Barış Tan is a Turkish business and engineering academic. He is a Professor of Operations Management and Industrial Engineering at Koç University, Turkey. He is most known for his research in the areas of production systems, supply chain management, and operations management. He served as the vice president of academic affairs, dean of College of Administrative Sciences and Economics and Director of Graduate School of Business at Koç University.\nTan has published over 100 papers and book chapters. He is the recipient of several best paper awards, and has been awarded Turkish Academy of Sciences Distinguished Young Scholar Award, TUBITAK fellowship, and NATO Science Fellowship. He is the manufacturing area editor of \"Flexible Services and Manufacturing Journal\" and associate editor of IISE Transactions. He also serves in for-profit and non-profit organizations as a board member.\nEducation.\nTan received his Bachelor’s degree in Electrical and Electronics Engineering from Boğaziçi University in 1990. He then moved to the United States, earning his M.E. degree in Industrial and Systems Engineering in 1991, M.S.E. Graduate Certificate in Manufacturing Systems in 1993, and Ph.D. in Industrial and Systems Engineering in 1994, at the University of Florida.\nCareer.\nTan began his academic career as a Research Assistant in Industrial Research Laboratory at the University of Florida in 1991 during his PhD studies. In 1994, upon moving back to Turkey, he joined Koç University as an Assistant Professor in College of Administrative Sciences and Economics. He was promoted to Associate Professor in 1998, and became a Professor in 2002. He has also been serving there as a Professor of Industrial Engineering since 2014.\nDuring his tenure at Koç University, Tan held several administrative appointments. He was the Dean of the College of Administrative Sciences and Economics during 2007-2013. Followed by this role, he served as Vice President for Academic Affairs from 2013 till 2021. He served twice as Director of Graduate School of Business (2003-2005 and 2008-2010).\nTan is a member of the advisory boards of Nottingham University Business School (United Kingdom), and Kyoto University Graduate School of Management (Japan). He is also an independent board member of Anadolu Efes, Migros, and Anadolu Isuzu. Since 1993, he has been a member of INFORMS. Moreover, he has served as the chair of the ISM University of Management and Economics Senate and on the boards of CEMS Global Alliance in Management Education, European Foundation for Management Development, EQUIS, Turkish Quality Association, and Turkish Operations Research Society.\nTan was a Fellow at the University of Cambridge – Judge Business School in 2013, and was a Visiting Professor at the University College London – School of Management from 2017 till 2019. Currently, he serves as a Visiting Professor at Politecnico di Milano, and Senior Research Fellow for ERA Project IN4ACT at Kaunas University of Technology. He has also been a visiting faculty at Harvard University and MIT \nResearch.\nTan has focused his research on design and control of manufacturing systems, business model innovation, supply chain management, and stochastic modelling. His research has been supported by TUBITAK, European Union Horizon 2020 and Horizon Europe programs.\nDesign and Control of Production Systems.\nTan developed analytical methods to determine performance measures (such as the throughput, distribution of amount of materials produced and cycle time related to material flow in production systems) to design and control of production systems. He developed analytical methods for the analysis of systems in which the material flow in production systems is modeled as a fluid. Tan also focused his research onto developing policies to control production resources dynamically to meet a random demand.\nIn 2005, he co-edited a book, \"Stochastic Modeling of Manufacturing Systems\", and explored the development and analysis of performance evaluation models of manufacturing systems while utilizing decomposition-based methods, Markovian and queuing analysis, and inventory control approaches. His 2013 edited book presented the state of the art in stochastic modeling of manufacturing systems, with a particular emphasis on critical stochastic performance analysis as well as integrated optimization models of these systems.\nMore recently, he focuses on the modeling and data-driven control of production for energy efficiency. He developed an approach for data-driven modeling and analysis of manufacturing systems that combines analytical modeling, optimization, simulation and machine learning methodologies using high-performance computing.\nSupply Chain Management.\nTan’s research in supply chain management focused on developing dynamic control policies for the use of production resources at different costs to meet variable demand, data-driven inventory management, and developing and analyzing cooperation-based business models. In early 2000s, he investigated the strategy of increasing production capacity temporarily through contingent contractual agreements with short-cycle manufacturers. He devised optimal control policies to use subcontractors together with the existing resources.\nTan has also worked on developing and analyzing cooperation-based business models. In his work related to data-driven inventory management, he developed methods to manage inventory accounting for substitution by using POS data. Tan also investigated the multi-product newsvendor problem while utilizing Value at Risk (VaR) as the risk measure in a newsvendor framework.\nStochastic Modelling.\nTan developed stochastic models and analysis methods for the solution of different decision problems. Tan's research in the areas of stochastic modelling includes models developed for determining the risks of accidents caused by oil tankers passing through the Bosphorus, determining the agricultural planting planning that takes into account the risks of harvest, yield and demand, developing new methods for testing the efficiency of stock markets, developing a new modeling approach to compare the growth dynamics in emerging markets, and presenting modeling and analytical approaches for different decision problems such as choosing energy saving methods in buildings, developing new business models for financing energy saving investments, and launching and pricing new products.", "Engineering,_Manufacturing": 0.9986737967, "qwen": "Yes"}
{"id": "21718903", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=21718903", "title": "Hobby injection molding", "text": "Hobby injection molding machines, also known as benchtop injectors, hold molds on a smaller scale. Benchtop injectors have become more common as inexpensive CNC milling machines have reduced the cost of producing molds in a home workshop.\nIn hobby injectors injection pressure is generated manually by the operator, with a lever or gear translating the operator's effort to the required pressure. The most common hobby injection machine uses a handle to press down with. This enables the user to generate roughly of downward force, through the use of leverage.\nHistory.\nIt is not known when the first hobby injection molder was constructed. Before the development of inexpensive CNC milling machines, producing a metal mold was prohibitively expensive for most hobbyists. With a small CNC mill and personal CAD tools, though, even complex shapes can be cut easily and accurately.\nApplications.\nHobby injection molding has a variety of applications including the creation of low cost prototypes, new inventions, replication of lost or broken parts, and provides homeowners the opportunity to build anything. Hobby injection molding is a low cost method of repeatable production.\nMaterials.\nPolyethylene (both LDPE and HDPE), polypropylene, and polystyrene (including HIPS) have all been used successfully with lever-actuated benchtop injectors.\nEquipment.\nBenchtop injectors are smaller and simpler than their larger industrious counterparts because they rely on the operator to manually inject melted polymer into the mold and remove the finished part from the mold. Production injectors automatically inject melted polymer at a prescribed rate into the mold, cool the mold to rapidly solidify the polymer, then eject the part from the mold once it's cool. The two halves of the mold must be pressed together with great force to prevent a flash in the part where the two halves meet, and the nozzle of the injector must be pressed tightly against the inlet port of the mold to prevent the escape of melted polymer and a defect in the finished part. In a benchtop injector this is done manually by clamping or bolting the mold together and clamping the complete mold into the injector. In a production injector this is accomplished with hydraulic or pneumatic actuators, which increase the cost of the machine but dramatically reduce the labor required to produce a finished part.\nMolds.\nMetal molds.\nLow cost benchtop CNC milling machines allow home enthusiasts to machine molds out of softer metals. Rather than P20 tool steel, most grades of aluminum can be machined into working molds capable of 1000 plus cycles. Mic 6 cast aluminum is more stable post machining and during cycles than hot extruded grades like 6061 and is easy to machine however it has worse mechanical properties. 7000 series like 7050 and 7075 are preferred for the best mechanical properties in aluminum, they are comparable to low to mid carbon steel molds. Copper alloys, like pewter, or bismuth alloy molds can be cast around a model to create strong molds with higher molding temperatures than epoxy molds. The casting around a model to create each mold part produces complex molds quickly. The parts can also capture detailed surface finishes.\nEpoxy Molds.\nEpoxy molds typically mix epoxy with a metal powder (generally aluminum) to form a mold. Atomized aluminum allows for the distribution of heat from the mold surface outward toward the edges. This typically preserves the surface quality for 50-100 cycles on a single epoxy mold.\nDue to the nature of oxygen entrapment in epoxy during the pouring and curing period it is common to have distortions and cavitation in the final injection mold. Pressurizing the epoxy during the curing period is a form of surface quality retention. External pressures can be created with the use of a pressure pot connected to an air compressor to crush air trapped inside the epoxy mold during curing. As time passes over a 24-hour period the oxygen bubbles will not be able to escape and will cure directly inside the mold. With sufficient pressure these small cavities will be invisible to the naked eye.\nDegassing the epoxy during the curing period can also be done using a vacuum chamber and will require a pressure of 100 kPa (29 inHg) in order to create near vacuum conditions. This can be achieved with the use of a 2-stage vacuum pump that is capable of 2 Pa (15 μmHg).\nSingle use molds.\nSingle use injection molds can be achieved through the use of plaster of Paris. The mold breaks down after the first shot and will rarely allow for the injection of a second shot.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "38443020", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=38443020", "title": "Forming (metalworking)", "text": "In metalworking, forming is the fashioning of metal parts and objects through mechanical deformation; the workpiece is reshaped without adding or removing material, and its mass remains unchanged. Forming operates on the materials science principle of plastic deformation, where the physical shape of a material is permanently deformed.\nCharacteristics.\nMetal forming tends to have more uniform characteristics across its subprocesses than its contemporary processes, cutting and joining. \nOn the industrial scale, forming is characterized by:\nForming processes.\nForming processes tend to be categorised by differences in effective stresses. These categories and descriptions are highly simplified, since the stresses operating at a local level in any given process are very complex and may involve many varieties of stresses operating simultaneously, or it may involve stresses which change over the course of the operation.\nCompressive forming involves those processes where the primary means of plastic deformation is uni- or multiaxial compressive loading.\nTensile forming.\nTensile forming involves those processes where the primary means of plastic deformation is uni- or multiaxial tensile stress.\nCombined tensile and compressive forming.\nThis category of forming processes involves those operations where the primary means of plastic deformation involves both tensile stresses and compressive loads.\nBending.\nThis category of forming processes involves those operations where the primary means of plastic deformation is a bending load.\nShearing.\nThis category of forming processes involves those operations where the primary means of plastic deformation is a shearing load.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "4635657", "revid": "43417927", "url": "https://en.wikipedia.org/wiki?curid=4635657", "title": "Titanium powder", "text": "Titanium powder metallurgy (P/M) offers the possibility of creating net shape or near net shape parts without the material loss and cost associated with having to machine intricate components from wrought billet. Powders can be produced by the blended elemental technique or by pre-alloying and then consolidated by metal injection moulding, hot isostatic pressing, direct powder rolling or laser engineered net shaping.\nBlended elemental technique (BE).\nThe traditional technique of titanium production is via the Kroll process which involves chlorination of TiO2 ore in the presence of carbon and reacting the resulting TiCl4 with magnesium to produce titanium sponge. These processes take place at temperatures as high as 1040 °C. The sponge particle range in size from 45 to 180 μm, with particles ~150 μm termed 'sponge fines'. These fines are irregularly shaped and porous with a sponge-like morphology. The fines are then blended with alloy additions; cold compacted into a green compact at up to 415 MPa then vacuum sintered at 1260 °C to produce a 99.5% dense component. Hot isostatic pressing (HIP) can further increase the density of these parts and produce components more economically than cast or wrought parts, but the porosity present in the material degrades fatigue and fracture properties. The BE approach has been used to produce valves for the Toyota Altezza, golf club heads and softball bats. More recently, close to 100% dense Ti Grade 5 parts has been achieved using a hydrided powder along with 60:40 Al:V master alloy. The mechanical properties compare well with those exhibited by cast-and-wrought products. A cost estimate of less than $3.00 for a 0.320 g automotive connection link has been made.\nPre-alloyed powder production.\nSeveral techniques exist to produce pre-alloyed powder, such as Grade 5. In the hydride-dehydride process feedstock such as solid scrap, billet or machined turnings are processed to remove contaminants, hydrogenated to produce brittle material then ground under argon in a vibratory ball mill, typically at 400 °C for 4 hours at a pressure of 1 psi for Ti Grade 5. The resulting particles are angular and measure between 50 and 300 μm. Cold compaction after dehydrogenation of the powder, followed by either vacuum hot pressing (in this case the dehydrogenation process can be bypassed as hydrogen is removed under vacuum) or HIP and a final vacuum anneal, produces powders with hydrogen below 125 ppm. The possible presence of contaminants makes these powders unsuitable for use in critical aircraft applications.\nIn the plasma rotating electrode process (PREP), the feedstock, such as Ti Grade 5, is in the form of a rotating bar which is arced with gas plasma. The molten metal is centrifugally flung off the bar, cools down and is collected. The powders produced are spherical; between 100 and 300 μm is size, with good packing and flow characteristics, making the powder ideal for high quality, near net shapes produced by HIP, such as aviation parts and porous coatings on hip prostheses.\nIn the titanium gas atomisation (TGA) process, titanium is vacuum induction skull melted in a water cooled copper crucible, the metal tapped and the molten metal stream atomized with a stream of high pressure inert gas. The tiny droplets are spherical and measure between 50 and 350 μm. The TGA process has been used to produce a wide variety of materials such as commercially pure (CP) titanium, conventional alpha-beta and beta alloys.\nIn plasma atomization (PA) process, a titanium wire is atomized by 3 inert gas plasma jets to form spherical metal powders. The distribution of diameter obtained in the PA process ranges between 0–200 μm and the powders obtained is very pure. The PA process specializes in the production of high temperature melting material as titanium (CP-Ti, Ti-6Al-4V), niobium, molybdenum, tantalum and many more.\nPowder consolidation.\nSeveral metal consolidation techniques are used to produce the final product. Metal injection moulding (MIM) otherwise known as powder injection moulding is a well-established and cost-effective method of fabricating small-to-moderate size metal components in large quantities. It is derived from the method plastic injection moulding, whereby mixing of a metal powder with a polymer binder forms the feedstock, which is then injected into a mould, after which the binder is removed via heat treatment under vacuum before final sintering. With titanium however, the binders used in MIM results in the introduction of carbon into the matrix due to insufficient binder removal prior to sintering and/or deleterious reactions between the decomposing binder, the debinding atmosphere, and the metal phase. This results in titanium parts with mechanical properties unsuited for critical aerospace applications, but suitable for parts where tensile and impact properties are less important. Recently, work has been carried out to reduce the binder to < 8% volume fraction, resulting in the complete removal of the binder from the moulded component during heat treatment.\nIn the direct powder rolling (DPR) process BE powder is used to produce sheet and plate and composite multilayered sheet and plates. Sheets between 1.27 and 2.54 mm and 50 to 99+% dense of single layer CP titanium, Ti Grade 5, TiAl (Ti-48Al-2Cr-2Nb) and composite Ti/Grade 5/Ti and Grade 5/TiAl/Grade 5 have been produced by DPR and sintering.\nLaser engineered net shaping (LENS) is an additive manufacturing technique for rapidly fabricating, enhancing and repairing metal components directly from CAD data. The processes use a high power solid state laser focused onto a metal substrate to create a ~1 mm diameter melt pool. Metal powder is then injected into the melt pool to increase the material volume and build up the component layer by layer. Experimental gas thrusters (build time 8 hours) and automotive brackets have been manufactured in Ti-Grade 5. Selective Laser Sintering (SLS) is similar, except that the laser selectively fuses powdered material by scanning on the surface of a powder bed. After each cross-section is scanned, the powder bed is lowered by one layer thickness, a new layer of material is applied on top, and the process is repeated until the part is completed.\nIn hot isostatic pressing high temperature and pressure are used to consolidate powders to close to their maximum theoretical densities.\nElectric current assisted sintering, also known as spark plasma sintering (SPS) relies on fast application of resistive heating and pressure to consolidate powders close to their maximum theoretical densities, without the undesired grain growth effect, thereby retaining close to original grain size and achieving improved mechanical properties in the final product.\nEmerging technologies.\nWork is progressing on bypassing the conventional route of atomising wrought feedstock or sponge and the inherent cost associated with the traditional Kroll process. Several of these processes, such as the FFC, MER Corporation, OS, Ginatta and BHP Billiton processes rely on the electrolytic reduction of TiO2 (a cheap and abundant material) to form Ti metal. So far, no material from these processes has been sold commercially on the open market, and cost models have yet to be published, but they offer the possibility of inexpensive titanium powder in the near future. The countries that have such facilities to generate Titanium Sponge are Saudi Arabia, China, Japan, Russia, Kazakhstan, the USA, Ukraine and India. The Titanium Sponge Plant in India is the only one in the world that can undertake all the different activities of manufacturing aerospace grade titanium sponge under one roof.", "Engineering,_Manufacturing": 0.9999988079, "qwen": "Yes"}
{"id": "471675", "revid": "41865877", "url": "https://en.wikipedia.org/wiki?curid=471675", "title": "Thermal-transfer printing", "text": "Thermal-transfer printing is a digital printing method in which material is applied to paper (or some other material) by melting a coating of ribbon so that it stays glued to the material on which the print is applied. It contrasts with direct thermal printing, where no ribbon is present in the process.\nThermal transfer is preferred over direct thermal printing on surfaces that are heat-sensitive or when higher durability of printed matter (especially against heat) is desired. Thermal transfer is a popular print process particularly used for the printing of identification labels. It is the most widely used printing process in the world for the printing of high-quality barcodes. Printers like label makers can laminate the print for added durability.\nThermal transfer printing was invented by SATO corporation. The world's first thermal-transfer label printer SATO M-2311 was produced in 1981.\nThermal-transfer printing process.\nThermal-transfer printing is done by melting wax within the print heads of a specialized printer. The thermal-transfer print process utilises three main components: a non-movable print head, a carbon ribbon (the ink) and a substrate to be printed, which would typically be paper, synthetics, card or textile materials. These three components effectively form a sandwich with the ribbon in the middle. A thermally compliant print head, in combination with the electrical properties of the ribbon and the correct rheological properties of the ribbon ink are all essential in producing a high-quality printed image.\nPrint heads are available in 203 dpi, 300 dpi and 600 dpi resolution options. Each dot is addressed independently, and when a dot is electronically addressed, it immediately heats up to a pre-set (adjustable) temperature. The heated element immediately melts the wax- or resin-based ink on the side of the ribbon film facing the substrate, and this process, in combination with the constant pressure being applied by the print-head locking mechanism immediately transfers it onto the substrate. When a dot \"turns off\", that element of the print head immediately cools down, and that part of the ribbon thereby stops melting/printing. As the substrate comes out of the printer, it is completely dry and can be used immediately.\nCarbon ribbons are on rolls and are fitted onto a spindle or reel holder within the printer. The used ribbon is rewound by a take-up spindle, forming a roll of \"used\" ribbon. It is termed a \"one-trip\" ribbon because once it has been rewound, the used roll is discarded and replaced with a new one. If one were to hold a strip of used carbon ribbon up to the light, one would see an exact negative of the images that have been printed. The main benefit of using a one-trip thermal transfer ribbon is that providing the correct settings are applied prior to printing, a 100% density of printed image is guaranteed, in contrast to a pre-inked ribbon on a dot-matrix impact printer ribbon, which gradually fades with usage.\nVariants.\nColor thermal printers.\nThermal-printing technology can be used to produce color images by adhering a wax-based ink onto paper. As the paper and ribbon travel in unison beneath the thermal print head, the wax-based ink from the transfer ribbon melts onto the paper. When cooled, the wax is permanently adhered to the paper. This type of thermal printer uses a like-sized panel of ribbon for each page to be printed, regardless of the contents of the page. Monochrome printers have a black panel for each page to be printed, while color printers have either three (CMY) or four (CMYK) colored panels for each page. Unlike dye-sublimation printers, these printers cannot vary the dot intensity, which means that images must be dithered. Although acceptable in quality, the printouts from these printers cannot compare with modern inkjet printers and color laser printers. Currently, this type of printer is rarely used for full-page printing, but is now employed for industrial label printing due to its waterfastness and speed. These printers are considered highly reliable due to their small number of moving parts. Printouts from color thermal printers using wax are sensitive to abrasion, as the wax ink can be scraped, rubbed off, or smeared. However, wax-resin compounds and full resins can be used on materials such as polypropylene or polyester in order to increase durability.\nTektronix/Xerox solid-ink printers.\nSo-called \"solid ink\" or \"phaser\" printers were developed by Tektronix and later by Xerox (who acquired Tektronix's printer division). Printers like the Xerox Phaser 8400 use rectangular solid-state ink blocks (similar in consistency to candle wax), which are loaded into a system similar to a stapler magazine in the top of the printer. The ink blocks are melted, and the ink is transferred onto a rotating oil-coated print drum using a piezo inkjet head. The paper then passes over the print drum, at which time the image is transferred, or transfixed, to the page. This system is similar to water-based inkjets, provided that the ink has low viscosity at the jetting temperature 60 °C (140 °F). Printout properties are similar to those mentioned above, although these printers can be configured to produce extremely high-quality results and are far more economical, as they only use the ink needed for the printout, rather than an entire ribbon panel. Costs of upkeep and ink are comparable to color laser printers, while \"standby\" power usage can be very high, about 200 W.\nALPS MicroDry printers.\nMicroDry is a computer printing system developed by the Alps Electric of Japan. It is a wax/resin-transfer system using individual colored thermal ribbon cartridges and can print in process color using cyan, magenta, yellow, and black cartridges, as well as such spot-color cartridges as white, metallic silver, and metallic gold, on a wide variety of paper and transparency stock. Certain MicroDry printers can also operate in dye-sublimation mode, using special cartridges and paper.\nUses.\nUsage of TT printers in industry includes:\nBarcode printers typically come in fixed sizes of wide. Although a number of manufacturers have made differing sizes in the past, most have now standardised on these sizes. The main application of these printers is to produce barcode labels for product and shipping identification.", "Engineering,_Manufacturing": 0.999392271, "qwen": "Yes"}
{"id": "55524455", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=55524455", "title": "Digital image correlation for electronics", "text": "Digital image correlation analyses have applications in material property characterization, displacement measurement, and strain mapping. As such, DIC is becoming an increasingly popular tool when evaluating the thermo-mechanical behavior of electronic components and systems.\nCTE measurements and glass transition temperature identification.\nThe most common application of DIC in the electronics industry is the measurement of coefficient of thermal expansion (CTE). Because it is a non-contact, full-field surface technique, DIC is ideal for measuring the effective CTE of printed circuit boards (PCB) and individual surfaces of electronic components. It is especially useful for characterizing the properties of complex integrated circuits, as the combined thermal expansion effects of the substrate, molding compound, and die make effective CTE difficult to estimate at the substrate surface with other experimental methods. DIC techniques can be used to calculate average in-plane strain as a function of temperature over an area of interest during a thermal profile. Linear curve-fitting and slope calculation can then be used to estimate an effective CTE for the observed area. Because the driving factor in solder fatigue is most often the CTE mismatch between a component and the PCB it is soldered to, accurate CTE measurements are vital for calculating printed circuit board assembly (PCBA) reliability metrics.\nDIC is also useful for characterizing the thermal properties of polymers. Polymers are often used in electronic assemblies as potting compounds, conformal coatings, adhesives, molding compounds, dielectrics, and underfills. Because the stiffness of such materials can vary widely, accurately determining their thermal characteristics with contact techniques that transfer load to the specimen, such as dynamic mechanical analysis (DMA) and thermomechanical analysis (TMA), is difficult to do with consistency. Accurate CTE measurements are important for these materials because, depending on the specific use case, expansion and contraction of these materials can drastically affect solder joint reliability. For example, if a stiff conformal coating or other polymeric encapsulation is allowed to flow under a QFN, its expansion and contraction during thermal cycling can add tensile stress to the solder joints and expedite fatigue failures.\nDIC techniques will also allow the detection of glass transition temperature (Tg). At a glass transition temperature, the strain vs. temperature plot will exhibit a change in slope.\nDetermining the Tg is very important for polymeric materials that could have glass transition temperatures within the operating temperature range of the electronics assemblies and components on which they are used. For example, some potting materials can see the Elastic Modulus of the material change by a factor of 100 or more over the glass transition region. Such changes can have drastic effects on an electronic assembly's reliability if they are not planned for in the design process.\nOut-of-plane component warpage.\nWhen 3D DIC techniques are employed, out-of-plane motion can be tracked in addition to in-plane motion. Out-of-plane warpage is especially of interest at the component level of electronics packaging for solder joint reliability quantification. Excessive warpage during reflow can contribute to defective solder joints by lifting the edges of the component away from the board and creating head-in-pillow defects in ball grid arrays (BGA). Warpage can also shorten the fatigue life of adequate joints by adding tensile stresses to edge joints during thermal cycling.\nThermo-mechanical strain mapping.\nWhen a PCBA is over-constrained, thermo-mechanical stress brought about during thermal expansion can cause board strains that could negatively affect individual component and overall assembly reliability. The full-field monitoring capabilities of an image correlation technique allow for the measurement of strain magnitude and location on the surface of a specimen during a displacement-causing event, such as PCBA during a thermal profile. These \"strain maps\" allow for the comparison of strain levels over full areas of interest. Many traditional discrete methods, like extensometers and strain gauges, only allow for localized measurements of strain, inhibiting their ability to efficiently measure strain across larger areas of interest. DIC techniques have also been used to generate strain maps from purely mechanical events, such as drop impact tests, on electronic assemblies.", "Engineering,_Manufacturing": 0.9999870062, "qwen": "Yes"}
{"id": "55524896", "revid": "42204915", "url": "https://en.wikipedia.org/wiki?curid=55524896", "title": "Cross section (electronics)", "text": "In electronics, a cross section, cross-section, or microsection, is a prepared electronics sample that allows analysis at a plane that cuts through the sample. It is a destructive technique requiring that a portion of the sample be cut or ground away to expose the internal plane for analysis. They are commonly prepared for research, manufacturing quality assurance, supplier conformity, and failure analysis. Printed wiring boards (PWBs) and electronic components and their solder joints are common cross sectioned samples. The features of interest to be analyzed in cross section can be nanometer-scale metal and dielectric layers in semiconductors up to macroscopic features such as the amount of solder that has filled into a large, 0.125in (3.18mm) diameter plated through hole.\nPreparation.\nCross sections can be prepared by several methods typically chosen based on the scale of the feature of interest because the technique affects the smoothness of the final polish. Smoother polishes allow an analysis of smaller features but can also take longer or be more expensive to prepare. Cross sectioning hard materials such as alumina might require a different technique than a soft material like gold or soft plastic.\nMechanical grinding and polishing.\nMechanical grinding and polishing is a common method of preparation to analyze features on the order of 1s to 10s of microns to macroscopic features. Samples may first be cut down in size, for example, around a via in a PWB or around a ceramic capacitor soldered to a PWB. Samples may be prepared by encapsulation in a rigid material such as epoxy to keep the sample intact during grinding and with a vacuum step to fill in air gaps and create a solid sample with no voids. However, cross sections of some samples can be prepared with no encapsulation.\nEncapsulated samples are prepared using a rough grinding medium to remove material from the sample until just before the plane of interest is reached. Equipment can help automate the process by holding grinding and polishing media firm and then spinning it so a sample can be pressed against it. Typical grinding media are silicon carbide and diamond, which can be in the form of disposable discs impregnated with the grinding media or a slurry applied to a reusable pad. Successively finer media are used to finish grinding to the plane of interest and to polish at the plane of interest. Each successively smaller grit is used to remove the scratches and damage caused by the previous grit.\nMechanical cutting or milling.\nSome equipment allows for preparation of cross sections by direct cutting or milling.\nOther techniques.\nFocused ion beam, ion beam milling, and cleaving are common techniques in the semiconductor fabrication industry.\nPrinted wiring boards.\nManufacturers of substrates used in electronics prepare cross sections of a final product for quality assurance. In cross section, the quality of drill holes can be assessed and the plating quality and thickness in vias can be measured. Voids in the substrate materials may be seen which show the quality of the lamination process.\nElectronic components.\nViewing the internal structures of electronic components by cross section can reveal problems with manufacturing and material quality. In integrated circuits, a cross section can reveal the die, and its active layers, the die paddle, and 1st level interconnect (wire bonds or solder bumps).\nSolder joints.\nCross sections of component solder joints are commonly prepared to assess the quality and extent of the metallurgical bond. This analysis can be used to help determine any issues during the soldering processes that could lead to solder fatigue and failure. Solder joint cross sections are also commonly prepared during failure analysis to see cracks in the solder. Crack morphology can lead to identification of the type of stress and ultimately the root cause of the solder joint failure.\nAnalysis techniques for cross sections.\nAnalysis of polished cross sections can be performed with a variety of techniques. Images are commonly taken with optical microscopy and scanning electron microscopy. Chemical analysis can be done with energy dispersive x-ray spectroscopy (EDS). Hardness testing can also be performed.", "Engineering,_Manufacturing": 1.0000070333, "qwen": "Yes"}
{"id": "55552490", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=55552490", "title": "Dye-and-pry", "text": "Dye-n-Pry, also called Dye And Pry, Dye and Pull, Dye Staining, or Dye Penetrant, is a destructive analysis technique used on surface mount technology (SMT) components to either perform failure analysis or inspect for solder joint integrity. It is an application of dye penetrant inspection.\nMethod.\nDye-n-Pry is a useful technique in which a dye penetrant material is used to inspect for interconnect failures in integrated circuits (IC). This is mostly commonly done on solder joints for ball grid array (BGA) components, although in some cases it can be done with other components or samples. The component of interest is submerged in a dye material, such as red steel dye, and placed under vacuum. This allows the dye to flow underneath the component and into any cracks or defects. The dye is then dried in an oven (preferably overnight) to prevent smearing during separation, which could lead to false results. The part of interest is mechanically separated from the printed circuit board (PCB) and inspected for the presence of dye. Any fracture surface or interface will have dye present, indicating the presence of cracks or open circuits. IPC-TM-650 Method 2.4.53 specifies a process for dye-n-pry.\nUse in failure analysis of electronics.\nDye-n-Pry is a useful failure analysis technique to detect cracking or open circuits in BGA solder joints. This has some practical advantages over other destructive techniques, such as cross sectioning, as it can inspect a full ball grid array which may consist of hundreds of solder joints. Cross sectioning, on the other hand, may only be able to inspect a single row of solder joints and requires a better initial idea of the failure site.\nDye-n-pry can be useful for detecting several different failure modes. This includes pad cratering or solder joint fracture from mechanical drop/shock, thermal shock, or thermal cycling. This makes it useful technique to incorporate into a reliability test plan as part of the post test failure inspection. It is also a useful method to inspect or diagnose failures due to manufacturing defects or design flaws. This includes defects such as black pad for PCBs with ENIG surface finishes or early failures due to excessive board flexure from depaneling or In-circuit test (ICT).", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "3183196", "revid": "196446", "url": "https://en.wikipedia.org/wiki?curid=3183196", "title": "Rolling (metalworking)", "text": "In metalworking, rolling is a metal forming process in which metal stock is passed through one or more pairs of rolls to reduce the thickness, to make the thickness uniform, and/or to impart a desired mechanical property. The concept is similar to the rolling of dough. Rolling is classified according to the temperature of the metal rolled. If the temperature of the metal is above its recrystallization temperature, then the process is known as hot rolling. If the temperature of the metal is below its recrystallization temperature, the process is known as cold rolling. In terms of usage, hot rolling processes more tonnage than any other manufacturing process, and cold rolling processes the most tonnage out of all cold working processes. Roll stands holding pairs of rolls are grouped together into rolling mills that can quickly process metal, typically steel, into products such as structural steel (I-beams, angle stock, channel stock), bar stock, and rails. Most steel mills have rolling mill divisions that convert the semi-finished casting products into finished products.\nThere are many types of rolling processes, including \"ring rolling\", \"roll bending\", \"roll forming\", \"profile rolling\", and \"controlled rolling\".\nIron and steel.\nThe earliest rolling mills in crude form but the same basic principles were found in Middle East and South Asia as early as 600 BCE. The invention of the rolling mill in Europe may be attributed to Leonardo da Vinci in his drawings. Earliest rolling mills were slitting mills, which were introduced from what is now Belgium to England in 1590. These passed flat bars between rolls to form a plate of iron, which was then passed between grooved rolls (slitters) to produce rods of iron. The first experiments at rolling iron for tinplate took place about 1670. In 1697, Major John Hanbury erected a mill at Pontypool to roll \"Pontypool plates\" – blackplate. Later this began to be rerolled and tinned to make tinplate. The earlier production of plate iron in Europe had been in forges, not rolling mills.\nThe slitting mill was adapted to producing hoops (for barrels) and iron with a half-round or other sections by means that were the subject of two patents of c. 1679.\nSome of the earliest literature on rolling mills can be traced back to the Swedish engineer Christopher Polhem in his \"Patriotista Testamente\" of 1761, where he mentions rolling mills for both plate and bar iron. He also explains how rolling mills can save on time and labor because a rolling mill can produce 10 to 20 or more bars at the same time.\nA patent was granted to Thomas Blockley of England in 1759 for the polishing and rolling of metals. Another patent was granted in 1766 to Richard Ford of England for the first tandem mill. A tandem mill is one in which the metal is rolled in successive stands; Ford's tandem mill was for hot rolling of wire rods.\nOther metals.\nRolling mills for lead seem to have existed by the late 17th century. Copper and brass were also rolled by the late 18th century.\nModern rolling.\nUntil well into the eighteenth century, rolling mills derived their power from water wheels. The first recorded use of a steam engine directly driving a mill is attributed to John Wilkinson's Bradley Works where, in 1786, a Boulton and Watt engine was coupled to a slitting and rolling mill. The use of steam engines considerably enhanced the production capabilities of the mills, until this \nform of power was displaced by electric motors soon after 1900.\nModern rolling practice can be attributed to the pioneering efforts of Henry Cort of Funtley Iron Mills, near Fareham in Hampshire, England. In 1783, a patent number was issued to Henry Cort for his use of grooved rolls for rolling iron bars. With this new design, mills were able to produce 15 times more output per day than with a hammer. Although Cort was not the first to use grooved rolls, he was the first to combine the use of many of the best features of various ironmaking and shaping processes known at the time. Thus modern writers have called him \"father of modern rolling\".\nThe first rail rolling mill was established by John Birkenshaw at Bedlington Ironworks in Northumberland, England, in 1820, where he produced fish-bellied wrought iron rails in lengths of 15 to 18 feet. With the advancement of technology in rolling mills, the size of rolling mills grew rapidly along with the size of the products being rolled. One example of this was at The Great Exhibition in London in 1851, where a plate 20 feet long, 3 feet wide, and 7/16 of an inch thick, and weighing 1,125 pounds, was exhibited by the Consett Iron Company. Further evolution of the rolling mill came with the introduction of three-high mills in 1853 used for rolling heavy sections.\nHot and cold rolling.\nHot rolling.\nHot rolling is a metalworking process that occurs above the recrystallization temperature of the material. After the grains deform during processing, they recrystallize, which maintains an equiaxed microstructure and prevents the metal from work hardening. The starting material is usually large pieces of metal, like semi-finished casting products, such as ingots, slabs, blooms, and billets. \nIf these products came from a continuous casting operation, the products are usually fed directly into the rolling mills at the proper temperature. In smaller operations, the material starts at room temperature and must be heated. This is done in a gas- or oil-fired soaking pit for larger workpieces; for smaller workpieces, induction heating is used. As the material is worked, the temperature must be monitored to make sure it remains above the recrystallization temperature.\nTo maintain a safety factor a \"finishing temperature\" is defined above the recrystallization temperature; this is usually 50 to 100 °C (90 to 180 °F) above the recrystallization temperature. If the temperature does drop below this temperature the material must be re-heated prior to additional hot rolling.\nHot-rolled metals generally have little directionality in their mechanical properties or deformation-induced residual stresses. However, in certain instances non-metallic inclusions will impart some directionality and workpieces less than thick often have some directional properties. Non-uniform cooling will induce a lot of residual stresses, which usually occurs in shapes that have a non-uniform cross-section, such as I-beams. While the finished product is of good quality, the surface is covered in mill scale, which is an oxide that forms at high temperatures. It is usually removed via pickling or the smooth clean surface (SCS) process, which reveals a smooth surface. Dimensional tolerances are usually 2 to 5% of the overall dimension.\nHot-rolled mild steel seems to have a wider tolerance for the level of included carbon than does cold-rolled steel, and is, therefore, more difficult for a blacksmith to use. Also for similar metals, hot-rolled products seem to be less costly than cold-rolled ones.\nHot rolling is used mainly to produce sheet metal or simple cross-sections, such as rail tracks. Other typical uses for hot-rolled metal:\nShape rolling design.\nRolling mills are often divided into roughing, intermediate and finishing rolling cages. During shape rolling, an initial billet (round or square) with edge of diameter typically ranging between 100 and 140 mm is continuously deformed to produce a certain finished product with smaller cross section dimension and geometry. Starting from a given billet, different sequences can be adopted to produce a certain final product. However, since each rolling mill is significantly expensive (up to 2 million euros), a typical requirement is to reduce the number of rolling passes. Different approaches have been achieved, including empirical knowledge, employment of numerical models, and Artificial Intelligence techniques. Lambiase et al. validated a finite element model (FE) for predicting the final shape of a rolled bar in round-flat pass. One of the major concerns when designing rolling mills is to reduce the number of passes. A possible solution to such requirements is the slit pass, also called split pass, which divides an incoming bar in two or more subparts, thus virtually increasing the cross section reduction ratio per pass as reported by Lambiase.\nAnother solution for reducing the number of passes in rolling mills is the employment of automated systems for Roll Pass Design as that proposed by Lambiase and Langella. subsequently, Lambiase further developed an Automated System based on Artificial Intelligence and particularly an integrated system including an inferential engine based on Genetic Algorithms a knowledge database based on an Artificial Neural Network trained by a parametric Finite element model and to optimize and automatically design rolling mills.\nCold rolling.\nCold rolling occurs with the metal below its recrystallization temperature (usually at room temperature), which increases the strength via strain hardening up to 20%. It also improves the surface finish and holds tighter tolerances. Commonly cold-rolled products include sheets, strips, bars, and rods; these products are usually smaller than the same products that are hot rolled. Because of the smaller size of the workpieces and their greater strength, as compared to hot rolled stock, four-high or cluster mills are used. Cold rolling cannot reduce the thickness of a workpiece as much as hot rolling in a single pass.\nCold-rolled sheets and strips come in various conditions: \"full-hard\", \"half-hard\", \"quarter-hard\", and \"skin-rolled\". Full-hard rolling reduces the thickness by 50%, while the others involve less of a reduction. Cold rolled steel is then annealed to induce ductility in the cold rolled steel which is simply known as a \"Cold Rolled and Close Annealed\". Skin-rolling, also known as a \"skin-pass\", involves the least amount of reduction: 0.5–1%. It is used to produce a smooth surface, a uniform thickness, and reduce the yield point phenomenon (by preventing Lüders bands from forming in later processing). It locks dislocations at the surface and thereby reduces the possibility of formation of Lüders bands. To avoid the formation of Lüders bands it is necessary to create substantial density of unpinned dislocations in ferrite matrix. It is also used to break up the spangles in galvanized steel. Skin-rolled stock is usually used in subsequent cold-working processes where good ductility is required.\nOther shapes can be cold-rolled if the cross-section is relatively uniform and the transverse dimension is relatively small. Cold rolling shapes requires a series of shaping operations, usually along the lines of sizing, breakdown, roughing, semi-roughing, semi-finishing, and finishing.\nIf processed by a blacksmith, the smoother, more consistent, and lower levels of carbon encapsulated in the steel makes it easier to process, but at the cost of being more expensive.\nTypical uses for cold-rolled steel include metal furniture, desks, filing cabinets, tables, chairs, motorcycle exhaust pipes, computer cabinets and hardware, home appliances and components, shelving, lighting fixtures, hinges, tubing, steel drums, lawn mowers, electronic cabinetry, water heaters, metal containers, fan blades, frying pans, wall and ceiling mount kits, and a variety of construction-related products.\nProcesses.\nRoll bending.\nRoll bending produces a cylindrical shaped product from plate or steel metals\nRoll forming.\nRoll forming, roll bending or plate rolling is a continuous bending operation in which a long strip of metal (typically coiled steel) is passed through consecutive sets of rolls, or stands, each performing only an incremental part of the bend, until the desired cross-section profile is obtained. Roll forming is ideal for producing parts with long lengths or in large quantities.\nThere are three main processes: 4 rollers, 3 rollers and 2 rollers, each of which has as different advantages according to the desired specifications of the output plate.\nFlat rolling.\nFlat rolling is the most basic form of rolling with the starting and ending material having a rectangular cross-section. The material is fed in between two \"rollers\", called \"working rolls\", that rotate in opposite directions. The gap between the two rolls is less than the thickness of the starting material, which causes it to deform. The decrease in material thickness causes the material to elongate. The friction at the interface between the material and the rolls causes the material to be pushed through. The amount of deformation possible in a single pass is limited by the friction between the rolls; if the change in thickness is too great the rolls just slip over the material and do not draw it in. The final product is either sheet or plate, with the former being less than thick and the latter greater than; however, heavy plates tend to be formed using a press, which is termed \"forging\", rather than rolling.\nOften the rolls are heated to assist in the workability of the metal. Lubrication is often used to keep the workpiece from sticking to the rolls. To fine-tune the process, the speed of the rolls and the temperature of the rollers are adjusted.\nFor thin sheet metal with a thickness less than , the rolling is done in a \"cluster mill\" because the small thickness requires a small diameter rolls. To reduce the need for small rolls \"pack rolling\" is used, which rolls multiple sheets together to increase the effective starting thickness. As the foil sheets come through the rollers, they are trimmed and slitted with circular or razor-like knives. Trimming refers to the edges of the foil, while slitting involves cutting it into several sheets. Aluminum foil is the most commonly produced product via pack rolling. This is evident from the two different surface finishes; the shiny side is on the roll side and the dull side is against the other sheet of foil.\nRing rolling.\nRing rolling is a specialized type of hot rolling that increases the diameter of a ring. The starting material is a thick-walled ring. This workpiece is placed between two rolls, an inner \"idler roll\" and a \"driven roll\", which presses the ring from the outside. As the rolling occurs the wall thickness decreases as the diameter increases. The rolls may be shaped to form various cross-sectional shapes. The resulting grain structure is circumferential, which gives better mechanical properties. Diameters can be as large as and face heights as tall as . Common applications include railway tyres, bearings, gears, rockets, turbines, airplanes, pipes, and pressure vessels.\nControlled rolling.\n\"Controlled rolling\" is a type of thermomechanical processing which integrates controlled deformation and heat treating. The heat which brings the workpiece above the recrystallization temperature is also used to perform the heat treatments so that any subsequent heat treating is unnecessary. Types of heat treatments include the production of a fine grain structure; controlling the nature, size, and distribution of various transformation products (such as ferrite, austenite, pearlite, bainite, and martensite in steel); inducing precipitation hardening; and, controlling the toughness. In order to achieve this the entire process must be closely monitored and controlled. Common variables in controlled rolling include the starting material composition and structure, deformation levels, temperatures at various stages, and cool-down conditions. The benefits of controlled rolling include better mechanical properties and energy savings.\nForge rolling.\nForge rolling is a longitudinal rolling process to reduce the cross-sectional area of heated bars or billets by leading them between two contrary rotating roll segments. The process is mainly used to provide optimized material distribution for subsequent die forging processes. Owing to this a better material utilization, lower process forces and better surface quality of parts can be achieved in die forging processes.\nBasically any forgeable metal can also be forge-rolled. Forge rolling is mainly used to preform long-scaled billets through targeted mass distribution for parts such as crankshafts, connection rods, steering knuckles and vehicle axles. Narrowest manufacturing tolerances can only partially be achieved by forge rolling. This is the main reason why forge rolling is rarely used for finishing, but mainly for preforming.\nCharacteristics of forge rolling:\nMills.\nA \"rolling mill\", also known as a \"reduction mill\" or \"mill\", has a common construction independent of the specific type of rolling being performed:\nSlabs are the feed material for hot strip mills or plate mills and blooms are rolled to billets in a billet mill or large sections in a structural mill. The output from a strip mill is coiled and, subsequently, used as the feed for a cold rolling mill or used directly by fabricators. Billets, for re-rolling, are subsequently rolled in either a merchant, bar or rod mill. Merchant or bar mills produce a variety of shaped products such as angles, channels, beams, rounds (long or coiled) and hexagons.\nConfigurations.\nMills are designed in different types of configurations, with the most basic being a \"two-high non-reversing\", which means there are two rolls that only turn in one direction. The \"two-high reversing\" mill has rolls that can rotate in both directions, but the disadvantage is that the rolls must be stopped, reversed, and then brought back up to rolling speed between each pass. To resolve this, the \"three-high\" mill was invented, which uses three rolls that rotate in one direction; the metal is fed through two of the rolls and then returned through the other pair. The disadvantage to this system is the workpiece must be lifted and lowered using an elevator. All of these mills are usually used for primary rolling and the roll diameters range from .\nTo minimize the roll diameter a \"four-high\" or \"cluster\" mill is used. A small roll diameter is advantageous because less roll is in contact with the material, which results in a lower force and power requirement. The problem with a small roll is a reduction of stiffness, which is overcome using \"backup rolls\". These backup rolls are larger and contact the back side of the smaller rolls. A four-high mill has four rolls, two small and two large. A cluster mill has more than four rolls, usually in three tiers. These types of mills are commonly used to hot roll wide plates, most cold rolling applications, and to roll foils. \nHistorically mills were classified by the product produced:\nTandem mill.\nA tandem mill is a special type of modern rolling mill where rolling is done in one pass. In a traditional rolling mill rolling is done in several passes, but in tandem mill there are several \"stands\" (>=2 stands) and reductions take place successively. The number of stands ranges from 2 to 18.\nTandem mills can be either of hot or cold rolling mill types.\nCold rolling mills may be further divided into continuous or batch processing.\nA continuous mill has a looping tower which allows the mill to continue rolling slowly the strip in the tower, while a strip welder joins the tail of the current coil to the head of the next coil. At the exit end of the mill there is normally a flying shear (to cut the strip at or near the weld) followed by two coilers; one being unloaded while the other winds on the current coil.\nLooping towers are also used in other places; such as continuous annealing lines and continuous electrolytic tinning and continuous galvanising lines.\nDefects.\nThickness changes along length.\nIn hot rolling, if the temperature of the workpiece is not uniform the flow of the material will occur more in the warmer parts and less in the cooler. If the temperature difference is great enough cracking and tearing can occur.\nThe cooler sections are, among other things, a result of the supports in the re-heat furnace.\nWhen cold rolling, virtually all of the strip thickness variation is the result of the eccentricity and out-of-roundness of the Back-up Rolls from about Stand 3 of the Hot Strip Mill through to the Finished Product. \nThe Back-up Roll eccentricity can be up to 100 μm in magnitude per stack. The eccentricity can be measured off-line by plotting the force variation against time with the Mill on creep, no strip present, and the Mill Stand below face.\nA modified Fourier analysis was employed by the 5 Stand Cold Mill at Bluescope Steel, Port Kembla from 1986 until that Cold Mill ceased production in 2009. Within each coil, the exit thickness deviation times 10 for every meter of strip was stored in a file. This file was analyzed separately for each frequency/wavelength from 5 m to 60 m in steps of 0.1 m. To improve the accuracy, care was taken to use a full multiple of each wavelength (100*). The calculate amplitudes were plotted against the wavelength, so that the spikes could be compared to the expected wavelengths created by the Backup Rolls of each Stand.\nIf a Mill Stand is fitted with Hydraulic Pistons in series with, or instead of the electrically driven Mechanical Screws, then it is possible to eliminate the effect of that Stands Back-up Roll eccentricity. While rolling, the eccentricity of each Back-up Roll is determined by sampling the roll force and assigning it to the corresponding portion of each Back-up Roll’s rotational position. These recordings are then used to operate the Hydraulic Piston so as to neutralize the eccentricities.\nFlatness and shape.\nIn a flat metal workpiece, the flatness is a descriptive attribute characterizing the extent of the geometric deviation from a reference plane. The deviation from complete flatness is the direct result of the workpiece relaxation after hot or cold rolling, due to the internal stress pattern caused by the non-uniform transversal compressive action of the rolls and the uneven geometrical properties of the entry material. The transverse distribution of differential strain/elongation-induced stress with respect to the material's average applied stress is commonly referenced to as shape. Due to the strict relationship between shape and flatness, these terms can be used in an interchangeable manner. \nIn the case of metal strips and sheets, the flatness reflects the differential fiber elongation across the width of the workpiece. This property must be subject to an accurate feedback-based control in order to guarantee the machinability of the metal sheets in the final transformation processes. Some technological details about the feedback control of flatness are given in.\nProfile.\nProfile is made up of the measurements of crown and wedge. Crown is the thickness in the center as compared to the average thickness at the edges of the workpiece. Wedge is a measure of the thickness at one edge as opposed to the other edge. Both may be expressed as absolute measurements or as relative measurements. For instance, one could have 2 mil of crown (the center of the workpiece is 2 mil thicker than the edges), or one could have 2% crown (the center of the workpiece is 2% thicker than the edges).\nIt is typically desirable to have some crown in the workpiece as this will cause the workpiece to tend to pull to the center of the mill, and thus will run with higher stability.\nFlatness.\nMaintaining a uniform gap between the rolls is difficult because the rolls deflect under the load required to deform the workpiece. The deflection causes the workpiece to be thinner on the edges and thicker in the middle. This can be overcome by using a crowned roller (parabolic crown), however the crowned roller will only compensate for one set of conditions, specifically the material, temperature, and amount of deformation.\nOther methods of compensating for roll deformation include continual varying crown (CVC), pair cross rolling, and work roll bending. CVC was developed by SMS-Siemag AG and involves grinding a third order polynomial curve into the work rolls and then shifting the work rolls laterally, equally, and opposite to each other. The effect is that the rolls will have a gap between them that is parabolic in shape, and will vary with lateral shift, thus allowing for control of the crown of the rolls dynamically. Pair cross rolling involves using either flat or parabolically crowned rolls, but shifting the ends at an angle so that the gap between the edges of the rolls will increase or decrease, thus allowing for dynamic crown control. Work roll bending involves using hydraulic cylinders at the ends of the rolls to counteract roll deflection.\nAnother way to overcome deflection issues is by decreasing the load on the rolls, which can be done by applying a longitudinal force; this is essentially drawing. Other method of decreasing roll deflection include increasing the elastic modulus of the roll material and adding back-up supports to the rolls.\nThe different classifications for flatness defects are:\nIt is important to note that one could have a flatness defect even with the workpiece having the same thickness across the width. Also, one could have fairly high crown or wedge, but still produce material that is flat. In order to produce flat material, the material must be reduced by the same percentage across the width. This is important because mass flow of the material must be preserved, and the more a material is reduced, the more it is elongated. If a material is elongated in the same manner across the width, then the flatness coming into the mill will be preserved at the exit of the mill.\nDraught.\nThe difference between the thickness of initial and rolled metal piece is called Draught.\nThus if formula_1 is initial thickness and formula_2 is final thickness, then the draught is given by\nThe maximum draught that can be achieved via rollers of radius with coefficient of static friction between the roller and the metal surface is given by\nThis is the case when the frictional force on the metal from inlet contact matches the negative force from the exit contact.\nSurface defect types.\nThere are six types of surface defects:\nSurface defect remediation.\nMany surface defects can be scarfed off the surface of semi-finished rolled products before further rolling. Methods of scarfing have included hand-chipping with chisels (18th and 19th centuries); powered chipping and grinding with air chisels and grinders; burning with an oxy-fuel torch, whose gas pressure blows away the metal or slag melted by the flame; and laser scarfing.", "Engineering,_Manufacturing": 0.9999639988, "qwen": "Yes"}
{"id": "3183236", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=3183236", "title": "Strut bar", "text": "A strut bar, strut brace, or strut tower brace (STB) is an automotive suspension accessory on a monocoque or unibody chassis to provide extra stiffness between the strut towers.\nWith a MacPherson strut suspension system where the spring and shock absorber combine in one suspension unit, which also replaces the upper control arm, the entire vertical suspension load is transmitted to the top of the vehicle's strut tower. This is different from a double wishbone suspension where the spring and shock absorber may share the load separately. In general terms, a strut tower in a monocoque chassis is a reinforced portion of the inner wheel well and is not necessarily directly connected to the main chassis rails. For this reason, there is inherent flex within the strut towers relative to the chassis rails.\nFunction.\nA strut bar is designed to reduce this strut tower flex by tying the two strut towers together. This transmits the load off each strut tower during cornering which ties the two towers together and reduces chassis flex. The transmission of load provides an increase in steering control accuracy going into a corner, reducing the possibility of the vehicle sliding or losing traction. To accomplish this effectively (especially on MacPherson strut suspensions), the bar must be rigid throughout its length. Many manufacturers have fitted strut braces to performance models as standard or optional equipment.\nTypes.\nMost strut bars follow one of two design types. These designs include:\nA single-piece strut bar is typically more durable and provides more rigidity as compared to the hinged type strut. However, the hinged type strut can allow for easier fitment of engine components due to its ability to move or pivot.\nBenefits.\nBeyond reducing chassis flex and increasing steering control accuracy in a corner, other benefits of strut bars include:\nDisadvantages.\nSome manufacturers have avoided the use of a strut bar due to a drawback in having the strut towers connected. The force from a significant impact or collision to one side of a vehicle would be distributed across the two struts leading to possible damages on both sides of the vehicle. This results in a higher repair cost.\nAlthough a strut bar is useful for improving the handling of a vehicle, in motorsports applications, the added weight from a traditional steel or aluminum strut bar can come as a disadvantage. To offset this issue, alternative materials for strut bars are being researched with carbon fiber being the main focus, as it can provide more strength in relation to its overall weight compared to most materials.", "Engineering,_Manufacturing": 1.0000053644, "qwen": "Yes"}
{"id": "17667699", "revid": "9755426", "url": "https://en.wikipedia.org/wiki?curid=17667699", "title": "Automotive hemming", "text": "Hemming is a technology used in the automotive industry to join inner and outer closure panels together (hoods, doors, tailgates, etc.). It is the process of bending/folding the flange of the outer panel over the inner one. The accuracy of the operation significantly affects the appearance of the car’s outer surfaces and is therefore a critical factor in the final quality of a finished vehicle.\nHemming processes.\nPress hemming.\nHemming presses are widely used in automotive manufacturing for hemming of sheet-metal body components. The process uses traditional hydraulically operated ‘stamping presses’ to hem closure parts, and, being the last forming process in stamping, it largely determines the external quality of such automotive parts as doors, hood and trunk lid.\nTable top hemming.\nTabletop hemming machines are utilised for the manufacture of medium to high production volumes, with the ability to achieve cycle times as low as 15 seconds.\nRobot (roller hemming).\nRobot hemming is utilized for the manufacture of Low to medium production volumes. It uses a standard industrial robot integrated with a roller hemming head to provide a flexible method for forming closures. The flange of the outer panel is bent over the inner panel in progressive steps, by means of a roller-hemming head.\nOne advantage of this process is that it can use the robot-controlled hemming head to hem several different components within a single cell. Another is that minor changes or fluctuations in panel-hemming conditions can be quickly and cost-effectively accommodated. If equipped with a tool-changing system, the robot could serve a variety of additional functions within the same assembly cell, such as operating dispensing equipment for adhesives and sealants, or carrying out panel manipulations, using a gripper unit.", "Engineering,_Manufacturing": 0.9999899864, "qwen": "Yes"}
{"id": "627366", "revid": "169132", "url": "https://en.wikipedia.org/wiki?curid=627366", "title": "Flexure bearing", "text": "A flexure bearing is a category of flexure which is engineered to be compliant in one or more angular degrees of freedom. Flexure bearings are often part of compliant mechanisms. Flexure bearings serve much of the same function as conventional bearings or hinges in applications which require angular compliance. However, flexures require no lubrication and exhibit very low or no friction.\nMany flexure bearings are made of a single part: two rigid structures joined by a thin \"hinge\" area. A hinged door can be created by implementing a flexible element between a door and the door frame, such that the flexible element bends allowing the door to pivot open.\nFlexure bearings have the advantage over most other bearings that they are simple and thus inexpensive. They are also often compact, lightweight, have very low friction, and are easier to repair without specialized equipment. Flexure bearings have the disadvantages that the range of motion is limited, and often very limited for bearings that support high loads.\nA flexure bearing relies on the bearing element being made of a material which can be repeatedly flexed without disintegrating. However, most materials lose strength and eventually fail with repeated flexing and bending. For example, most metals will fatigue with repeated flexing, and will eventually snap. Thus, one part of flexure bearing design is the careful consideration of material properties to avoid fatigue with normal use.\nFlexure bearings can give very low friction and also give very predictable friction. Many other bearings rely on sliding or rolling motions (rolling-element bearings), which are necessarily uneven because the bearing surfaces are never perfectly flat. A flexure bearing operates by bending of materials, which causes motion at microscopic level, so friction is very uniform. For this reason, flexure bearings are often used in sensitive precision measuring equipment.\nMany types of flexure bearings are not limited to low loads, however. For example, the drive shafts of some sports cars replace cardan universal joints with an equivalent joint called a rag joint which works by bending rubberized fabric. The resulting joint is lighter yet is capable of carrying hundreds of kilowatts, with adequate durability for a sports car. \nBecause flexure bearings do not rely on sliding or rolling motions, they do not require lubrication. Consequently, they can be employed in abrasive environments and environments hostile to lubricants: underwater, in a vacuum and at elevated temperatures.", "Engineering,_Manufacturing": 1.0000082254, "qwen": "Yes"}
{"id": "62925989", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=62925989", "title": "Parallel task scheduling", "text": "Parallel task scheduling (also called parallel job scheduling or parallel processing scheduling) is an optimization problem in computer science and operations research. It is a variant of optimal job scheduling. In a general job scheduling problem, we are given \"n\" jobs \"J\"1, \"J\"2, ..., \"Jn\" of varying processing times, which need to be scheduled on \"m\" machines while trying to minimize the makespan - the total length of the schedule (that is, when all the jobs have finished processing). In the specific variant known as \"parallel-task scheduling\", all machines are identical. Each job \"j\" has a \"length\" parameter \"pj\" and a \"size\" parameter \"q\"j, and it must run for exactly \"pj\" time-steps on exactly \"q\"j machines in \"parallel\".\nVeltman et al. and Drozdowski denote this problem by formula_1 in the three-field notation introduced by Graham et al. P means that there are several identical machines running in parallel; \"sizej\" means that each job has a size parameter; \"C\"max means that the goal is to minimize the maximum completion time. Some authors use formula_2 instead. Note that the problem of parallel-machines scheduling is a special case of parallel-task scheduling where formula_3 for all \"j\", that is, each job should run on a single machine.\nThe origins of this problem formulation can be traced back to 1960. For this problem, there exists no polynomial time approximation algorithm with a ratio smaller than formula_4 unless formula_5.\nDefinition.\nThere is a set formula_6 of formula_7 jobs, and formula_8 identical machines. Each job formula_9 has a processing time formula_10 (also called the \"length\" of \"j\"), and requires the simultaneous use of formula_11 machines during its execution (also called the \"size\" or the \"width\" of j).\nA schedule assigns each job formula_9 to a starting time formula_13 and a set formula_14 of formula_15 machines to be processed on. A schedule is feasible if each processor executes at most one job at any given time.\nThe objective of the problem denoted by formula_1 is to find a schedule with minimum length formula_17, also called the makespan of the schedule.\nA sufficient condition for the feasibility of a schedule is the following\nformula_18.\nIf this property is satisfied for all starting times, a feasible schedule can be generated by assigning free machines to the jobs at each time starting with time formula_19. Furthermore, the number of machine intervals used by jobs and idle intervals at each time step can be bounded by formula_20. Here a machine interval is a set of consecutive machines of maximal cardinality such that all machines in this set are processing the same job. A machine interval is completely specified by the index of its first and last machine. Therefore, it is possible to obtain a compact way of encoding the output with polynomial size.\nComputational hardness.\nThis problem is NP-hard even when there are only two machines and the sizes of all jobs are formula_21 (i.e., each job needs to run only on a single machine). This special case, denoted by formula_22, is a variant of the partition problem, which is known to be NP-hard.\nWhen the number of machines \"m\" is at most 3, that is: for the variants formula_23 and formula_24, there exists a pseudo-polynomial time algorithm, which solves the problem exactly.\nIn contrast, when the number of machines is at least 4, that is: for the variants formula_25 for any formula_26, the problem is also strongly NP-hard (this result improved a previous result showing strong NP-hardness for formula_27).\nIf the number of machines is not bounded by a constant, then there can be no approximation algorithm with an approximation ratio smaller than formula_4 unless formula_29. This holds even for the special case in which the processing time of all jobs is formula_30, since this special case is equivalent to the bin packing problem: each time-step corresponds to a bin, \"m\" is the bin size, each job corresponds to an item of size \"qj\", and minimizing the makespan corresponds to minimizing the number of bins.\nVariants.\nSeveral variants of this problem have been studied. The following variants also have been considered in combination with each other.\nContiguous jobs: In this variant, the machines have a fixed order formula_31. Instead of assigning the jobs to any subset formula_32, the jobs have to be assigned to a \"contiguous interval\" of machines. This problem corresponds to the problem formulation of the strip packing problem.\nMultiple platforms: In this variant, the set of machines is partitioned into independent platforms. A scheduled job can only use the machines of one platform and is not allowed to span over multiple platforms when processed.\nMoldable jobs: In this variant each job formula_9 has a set of feasible machine-counts formula_34. For each count formula_35, the job can be processed on \"d\" machines in parallel, and in this case, its processing time will be formula_36. To schedule a job formula_9, an algorithm has to choose a machine count formula_35 and assign \"j\" to a starting time formula_39 and to formula_40 machines during the time interval formula_41 A usual assumption for this kind of problem is that the total workload of a job, which is defined as formula_42, is non-increasing for an increasing number of machines.\nRelease dates: In this variant, denoted by formula_43, not all jobs are available at time 0; each job \"j\" becomes available at a fixed and known time \"rj\". It must be scheduled after that time.\nPreemption: In this variant, denoted by formula_44, it is possible to interrupt jobs that are already running, and schedule other jobs that become available at that time.\nAlgorithms.\nThe list scheduling algorithm by Garey and Graham has an absolute ratio formula_45, as pointed out by Turek et al. and Ludwig and Tiwari. \nFeldmann, Sgall and Teng observed that the length of a non-preemptive schedule produced by the list scheduling algorithm is actually at most formula_46 times the optimum preemptive makespan.\nA polynomial-time approximation scheme (PTAS) for the case when the number formula_8 of processors is constant, denoted by formula_25, was presented by Amoura et al. and Jansen et al.\nLater, Jansen and Thöle found a PTAS for the case where the number of processors is polynomially bounded in the number of jobs. \nIn this algorithm, the number of machines appears polynomially in the time complexity of the algorithm. \nSince, in general, the number of machines appears only in logarithmic in the size of the instance, this algorithm is a pseudo-polynomial time approximation scheme as well. \nA formula_49-approximation was given by Jansen, which closes the gap to the lower bound of formula_4 except for an arbitrarily small formula_51.\nDifferences between contiguous and non-contiguous jobs.\nGiven an instance of the parallel task scheduling problem, the optimal makespan can differ depending on the constraint to the contiguity of the machines. If the jobs can be scheduled on non-contiguous machines, the optimal makespan can be smaller than in the case that they have to be scheduled on contiguous ones.\nThe difference between contiguous and non-contiguous schedules has been first demonstrated in 1992 on an instance with formula_52 tasks, formula_53 processors, formula_54, and formula_55.\nBłądek et al. studied these so-called c/nc-differences and proved the following points:\nFurthermore, they proposed the following two conjectures, which remain unproven:\nRelated problems.\nThere are related scheduling problems in which each job consists of several operations, which must be executed \"in sequence\" (rather than in parallel). These are the problems of open shop scheduling, flow shop scheduling and job shop scheduling.", "Engineering,_Manufacturing": 0.9999517202, "qwen": "Yes"}
{"id": "351216", "revid": "31026899", "url": "https://en.wikipedia.org/wiki?curid=351216", "title": "Stripboard", "text": "Stripboard is the generic name for a widely used type of electronics prototyping material for circuit boards characterized by a pre-formed regular (rectangular) grid of holes, with wide parallel strips of copper cladding running in one direction all the way across one side of on an insulating bonded paper board. It is commonly also known by the name of the original product Veroboard, which is a trademark, in the UK, of British company Vero Technologies Ltd and Canadian company Pixel Print Ltd. It was originated and developed in the early 1960s by the Electronics Department of Vero Precision Engineering Ltd (VPE). It was introduced as a general-purpose material for use in constructing electronic circuits - differing from purpose-designed printed circuit boards (PCBs) in that a variety of electronics circuits may be constructed using a standard wiring board.\nIn using the board, breaks are made in the tracks, usually around holes, to divide the strips into multiple electrical nodes. With care, it is possible to break between holes to allow for components that have two pin rows only one position apart such as twin row headers for IDCs.\nStripboard is not designed for surface-mount components, though it is possible to mount many such components on the track side, particularly if tracks are cut/shaped with a knife or small cutting disc in a rotary tool.\nThe first single-size Veroboard product was the forerunner of the numerous types of prototype wiring board which, with worldwide use over five decades, have become known as stripboard.\nThe generic terms 'veroboard' and 'stripboard' are now taken to be synonymous.\nHistory.\nBy the mid-1950s, the printed circuit board (PCB) had become commonplace in electronics production.\nIn early 1959, the VPE Electronics Department was formed when managing director Geoffrey Verdon-Roe hired two former Saunders-Roe Ltd employees, Peter H Winter (aircraft design department) and Terry Fitzpatrick (electronics division).\nAfter the failure of a project to develop machine tool control equipment, the department remained operative as a result of success with the invention and development of the new material.\nNew equipment using PCBs was displayed at the 1959 Radio and Electronics Components Manufacturers Federation (RECMF) Exhibition held in The Dorchester Hotel, Park Lane, London.\nThe usual configuration for most of the PCBs of that time had components placed in a regular pattern with the circuit formed by maze-like conductive pathways. An interesting alternative, proposed by Fitzpatrick after visiting the RECMF Exhibition on behalf of VPE, envisaged a standard circuit board carrying straight-line conductors on which the components could be suitably dispersed and connected to the conductors to produce the required circuit.\nA patent application was immediately filed 25 May 1959 and the invention was developed for Vero by associates Winter, Fitzpatrick and machine shop engineers.\nThe advent of the Arduino integrated development environment, designed to introduce computer programming to newcomers unfamiliar with software development, presents a new opportunity to use Veroboard. Arduino development regularly involves the use of 'shields', which plug into the main Arduino board using standard 0.1 in header connections and carry project-specific I/O hardware. However the Arduino design makes this difficult, as one of the four header sockets is offset from the 0.1 in spacing of the others by 0.05 in.\nThe British company Vero Technologies Ltd currently holds the UK trademark for Veroboard. In the Americas the Veroboard trademark is now held by the Canadian company Pixel Print Ltd. of Vancouver.\nHole spacing.\nStripboard holes are drilled on centers. This spacing allows components having pins with a spacing to be inserted. Compatible parts include DIP ICs, sockets for ICs, some types of connectors, and other devices.\nStripboards have evolved over time into several variants and related products. For example, a larger version using a 0.15 inch (3.81 mm) grid and larger holes is available, but is generally less popular (presumably because it does not match up with standard IC pin spacing).\nBoard dimensions.\nStripboard is available in a variety of sizes. One common size (at least in the United Kingdom) is 160 mm x 100 mm.\nAssemblies.\nThe components are usually placed on the plain side of the board, with their leads protruding through the holes. The leads are then soldered to the copper tracks on the other side of the board to make the desired connections, and any excess wire is cut off. The continuous tracks may be easily and neatly cut as desired to form breaks between conductors using a 3 mm twist drill, a hand cutter made for the purpose, or a knife. Tracks may be linked up on either side of the board using wire. With practice, very neat and reliable assemblies can be created, though such a method is labour-intensive and therefore unsuitable for production assemblies except in very small quantity.\nExternal wire connections to the board are made either by soldering the wires through the holes or, for wires too thick to pass through the holes, by soldering them to specially made pins called Veropins which fit tightly into the holes. Alternatively, some types of connectors have a suitable pin spacing to be inserted directly into the board.\nProduction.\nProduction of the proposed new product, Veroboard, was undertaken by the VPE machine tool department.\nBought-in sheets of 1.6 mm (0.06 in) copper-clad SRBP printed circuit material were cut to give 122 mm x 456 mm (4.8 in x 18 in) size boards with the individual boards then being machined to form the final product according to the original Veroboard specification. A multiple milling cutter tool, which comprised a bank of side-and-face cutters with suitably shaped cutting teeth, was fabricated, to be used in removing part of the bonded copper on each board leaving 21 conductive strips.\nFor a second operation a special tool with 63 hardened punch bits 1.35 mm (0.052 in) in diameter mounted on a solid base block was constructed to repeat-punch a matrix of holes, on spacing, through the copper strips and the base board.\nMany dimensional, material quality, and tooling problems were encountered before finished boards of acceptable quality could be produced in quantity. These machining problems were encountered due to the non-availability, in 1960, of advanced printed circuit board milling and drilling techniques or facilities for chemical milling (etching) the copper strips.\nIn 1961, as production rates improved with experience, Vero Electronics Ltd was formed as a separate company to market the increasing sales of Veroboard.\nUse.\nAs with other stripboards, in using Veroboard, components are suitably positioned and soldered to the conductors to form the required circuit. Breaks can be made in the tracks, usually around holes, to divide the strips into multiple electrical nodes enabling increased circuit complexity.\nThis type of wiring board may be used for initial electronic circuit development, to construct prototypes for bench testing or in the production of complete electronic units in small quantity.\nVeroboard was first used for prototype construction within Vero Electronics Department in 1961. The images of a binary decade counter sub-unit clearly show both the assembled components and the copper conductors with the required discontinuities.\nA number of these sub-units were interconnected through connectors mounted on a motherboard similar to that shown in the Veroboard Display image and comprised a very early PCB-based backplane system. Each sub-unit had a digital capacity equivalent to 1/2 byte of data storage - i.e. 2,000,000 would be required to store 1 megabyte.\nTwo forms of Veroboard are produced with hole pitch of 2.54 mm (0.1 in) or 3.5 mm (0.15 in). The larger pitch is and was considered easier to assemble, especially at a time when many constructors were still more familiar with valves and tag strips.\nThe increasingly popular integrated circuits in dual in-line packages would only fit the 0.1 boards. Very soon 0.1 pitch became by far the dominant form. Integrated circuits and the common layout of short parallel strips protruding from the sides of an IC package encouraged the development of specialist boards such as Verostrip. This was a long, thin board with the copper strips arranged transversely, rather than the usual lengthwise. A ready-cut central gap was provided to isolate the sides of the IC.\nA 1979 Vero Electronics Ltd production drawing shows a special Veroboard product made for RS Components Ltd. The versatility of the veroboard/stripboard type of product is demonstrated by the large number of design examples currently (2013-07) to be found on the Internet.\nVariations.\nStripboard is available from many vendors. All versions have copper strips on one side. Some are made using printed circuit board etching and drilling techniques, although some have milled strips and punched holes. The original Veroboard used FR-2 synthetic-resin-bonded paper (SRBP) (also known as phenolic board) as the base board material. Some versions of stripboard now use higher quality FR-4 (fiberglass-reinforced epoxy laminate) material.\nComparison with other systems.\nFor high density prototyping, especially of digital circuits, wire wrap is faster and more reliable than Stripboard for experienced personnel.\nVeroboard is similar in concept and usage to a plug-in breadboard, but is cheaper and more permanent—connections are soldered and while some limited reuse may be possible, more than a few cycles of soldering and desoldering are likely to render both the components and the board unusable. In contrast, breadboard connections are held by friction, and the breadboard can be reused many times. However, a breadboard is not very suitable for prototyping that needs to remain in a set configuration for an appreciable period of time nor for physical mock-ups containing a working circuit or for any environment subject to vibration or movement.\nStripboards have further evolved into a larger class of prototype boards, available in different shapes and sizes, with different conductive trace layouts.\nFor example, one variant is called a TriPad board. This is similar to stripboard, except that the conductive tracks do not run continuously along the board but are broken into sections, each of which spans three holes. This allows the legs of two or three components to be easily linked together in the circuit conveniently without the need for track breaks to be made. However, in order to link more than three holes together, wire links or bridges must be formed and this can result in a less compact layout than is possible with ordinary stripboard.\nAnother variant is Perf+. This is best described as a selective stripboard. Instead of having all the holes connected together in a strip, a Perf+ board can have holes connected to the bus using a small dab of solder. On the other side the busses run in another direction, allowing compact layouts of complicated circuits by passing signals over each other on different layers of the board.\nOther prototype board variants have generic layouts to simplify building prototypes with integrated circuits, typically in DIP shapes, or with transistors (pads forming triangles). In particular, some boards mimic the layout of breadboards, to simplify moving a non-permanent prototype on a breadboard to a permanent construction on a PCB. Some types of boards have patterns for connectors on the periphery, like DB9 or IDC headers, to allow connectors with non-standard pin spacings to be easily used. Some come in special physical shapes, to be used to prototype plug-in boards for computer bus systems.", "Engineering,_Manufacturing": 0.9991201758, "qwen": "Yes"}
{"id": "351882", "revid": "764407", "url": "https://en.wikipedia.org/wiki?curid=351882", "title": "Automotive engineering", "text": "Automotive engineering, along with aerospace engineering and naval architecture, is a branch of vehicle engineering, incorporating elements of mechanical, electrical, electronic, software, and safety engineering as applied to the design, manufacture and operation of motorcycles, automobiles, and trucks and their respective engineering subsystems. It also includes modification of vehicles. Manufacturing domain deals with the creation and assembling the whole parts of automobiles is also included in it. The automotive engineering field is research intensive and involves direct application of mathematical models and formulas. The study of automotive engineering is to design, develop, fabricate, and test vehicles or vehicle components from the concept stage to production stage. Production, development, and manufacturing are the three major functions in this field.\nDisciplines.\nAutomobile engineering.\nAutomobile engineering is a branch study of engineering", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "16662343", "revid": "39191556", "url": "https://en.wikipedia.org/wiki?curid=16662343", "title": "Hubbing", "text": "Hubbing is a metalworking process that is used to make dies. It is a cold-working process, which means that it occurs well below the melting temperature of the metal being worked.\nProcess.\nIn hubbing, a male hub (master) is created with a profile that will form an impression on the female piece. The male hub is generally hardened and the female die block softened by annealing to help form the impression. As the metal flows the face of the die block is deformed, and, generally, must be machined flat. The die block is often a cylinder that is reinforced with a surrounding steel ring during the hubbing process. Hubbing is usually less expensive than die sinking, i.e., machining the female die, and multiple dies can be made from the male hub.\nIn the case of mild steel, a typical hubbing press exerts a pressure of approximately 1500 short tons-force per square inch (21 GPa) to transfer the image from a master hub into the master die.", "Engineering,_Manufacturing": 0.9999705553, "qwen": "Yes"}
{"id": "16690157", "revid": "5846", "url": "https://en.wikipedia.org/wiki?curid=16690157", "title": "Solution selling", "text": "Solution selling is a type and style of sales and selling methodology. Solution selling has a salesperson or sales team use a sales process that is a problem-led (rather than product-led) approach to determine if and how a change in a product could bring specific improvements that are desired by the customer. The term \"solution\" implies that the proposed new product produces improved outcomes and successfully resolves the customer problem. Business-to-business sales (B2B) organizations are more likely to use solution selling and similar sales methodologies.\nSolution selling has value and application in high complexity sales and selling situations. This complexity can be the result of existing customer circumstances, or the proposed combination of new products required, or a combination of each, such that the seller and the buyer must consider and compare many interrelated factors to achieve the desired solution and outcome. Enterprise-class software development projects, technical integration projects, large plant engineering projects, or construction projects are examples that illustrate high complexity situations. Selling organizations use a solution selling approach when one or more of the following circumstances exist:\nAccording to the solution selling methodology, there is a formula for selling. Set each of these parameter to one or zero, because you need them all:\nPain x Power x Vision x Value x Control = Sale.\nOrigins of solution selling and terminology.\nFrank Watts developed the sales process dubbed \"solution selling\" in 1975. Watts perfected his method at Wang Laboratories. He began teaching solution selling as an independent consultant in 1982. He presented his sales process as a one-day workshop to Xerox Corporation in 1982. By 1983 \"Electronics\" magazine would portray solution selling as \"an unmistakable trend in the distribution of systems-related products\".\nIn a 1984 account Dick Heiser could look back to IBM's pre-1975 \"solution sale\" methodology.\nMike Bosworth founded a sales training organization known as Solution Selling in 1983, based on his experiences at Xerox Corporation (the Huthwaite International SPIN (Situation, Problem, Implication, Need-payoff) selling pilot project)\nand began licensing affiliates in 1988. With intellectual-property contributions from his affiliate network, Bosworth's methodology continued to evolve through the years. He sold the intellectual property in 1999 to one of his original affiliates, Keith M. Eades.\nWhile 'solution selling' has become a generic term in many sales and selling organizations, Solution Selling as a brand denotes distinct characteristics. Followers of \"solution-selling\" generally apply a consultative sales approach to all aspects of their sales process (or cycle) including:\nThe solution selling methodology has evolved as key components of professional selling evolve. As a result, solution selling has become more broadly defined — to include dimensions of \"sales process\", \"competitive selling\", \"value selling\" as well as \"consultative selling\" or \"complex selling\" which set the focus on the team's aspects of the sales.\nSolution selling in management contexts.\nThe advent of solution selling may have an impact on business models and on organization practices.\nEades and Kear discuss solution-centric organizations and the focal role of solution sales in such environments.\nRobert J Calvin compares some of the financial implications of various type of sales: transactional sales, value-added sales, solution sales, and feature/benefit sales. Robert L Jolles proposed that, among managers and salespeople, a chosen solution is not always the best solution.", "Engineering,_Manufacturing": 0.99683851, "qwen": "Yes"}
{"id": "8344429", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=8344429", "title": "Value-stream mapping", "text": "Value-stream mapping, also known as material- and information-flow mapping, is a lean-management method for analyzing the current state and designing a future state for the series of events that take a product or service from the beginning of the specific process until it reaches the customer. A value stream map is a visual tool that displays all critical steps in a specific process and easily quantifies the time and volume taken at each stage. Value stream maps show the flow of both materials and information as they progress through the process.\nWhereas a value stream map represents a core business process that adds value to a material product, a value chain diagram shows an overview of all activities within a company. Other business activities may be represented in \"value stream diagrams\" and/or other kinds of diagram that represent business processes that create and use business data.\nPurpose.\nThe purpose of value-stream mapping is to identify and remove or reduce \"waste\" in value streams, thereby increasing the efficiency of a given value stream. Waste removal is intended to increase productivity by creating leaner operations which in turn make waste and quality problems easier to identify.\nApplications.\nValue-stream mapping has supporting methods that are often used in Lean environments to analyze and design flows at the system level (across multiple processes).\nAlthough value-stream mapping is often associated with manufacturing, it is also used in logistics, supply chain, service related industries, healthcare, software development, product development, project management, and administrative and office processes.\nIdentifying waste.\nTypes of waste.\nDaniel T. Jones (1995) identifies seven commonly accepted types of waste. These terms are updated from Toyota's operating model \"The Toyota Way\" (Toyota Production System, TPS) original nomenclature (muda):\nWaste removal operations.\nYasuhiro Monden (1994) identifies three types of operations:\nNNVA activities may also be referred to as \"sustaining non-value adding\", i.e. they have to be done, or they are necessary to sustain the business but do not contribute to customer requirements.\nFor additional views on waste, see Lean manufacturing.\nUsing the method.\nThere are two kinds of value stream maps, current state and future state. The current state value stream map is used to determine what the process currently looks like, the future state value stream map focuses on what the process will ideally look like after process improvements have occurred to the value stream.\nThe current state value stream map must be created before the future state map and is created by observing the process and tracking the information and material flow. The value stream map is then created using the following symbols:\nIn a build-to-the-standard form, Shigeo Shingo suggests that the value-adding steps be drawn across the centre of the map and the non–value-adding steps be represented in vertical lines at right angles to the value stream. Thus, the activities become easily separated into the value stream, which is the focus of one type of attention, and the \"waste\" steps, another type. He calls the value stream the process and the non-value streams the operations. The thinking here is that the non–value-adding steps are often preparatory or tidying up to the value-adding step and are closely associated with the person or machine/workstation that executes that value-adding step. Therefore, each vertical line is the \"story\" of a person or workstation whilst the horizontal line represents the \"story\" of the product being created.\nValue-stream mapping is a recognised method used as part of Lean Six Sigma methodologies.\nValue-stream mapping analyzes both material (artifact) and information flow. The following two resources exemplify the use of VSM in the context of software process improvement in industrial settings:\nAssociated analysis methods.\nHines and Rich (1997) defined seven value-stream mapping tools. These are:", "Engineering,_Manufacturing": 0.9988223314, "qwen": "Yes"}
{"id": "19916234", "revid": "33011235", "url": "https://en.wikipedia.org/wiki?curid=19916234", "title": "Integrated passive devices", "text": "Integrated passive devices (IPDs), also known as integrated passive components (IPCs) or embedded passive components (EPC), are electronic components where resistors (R), capacitors (C), inductors (L)/coils/chokes, microstriplines, impedance matching elements, baluns or any combinations of them are integrated in the same package or on the same substrate. Sometimes integrated passives can also be called as embedded passives, and still the difference between integrated and embedded passives is technically unclear. In both cases passives are realized in between dielectric layers or on the same substrate.\nThe earliest form of IPDs are resistor, capacitor, resistor-capacitor (RC) or resistor-capacitor-coil/inductor (RCL) networks. Passive transformers can also be realised as integrated passive devices like by putting two coils on top of each other separated by a thin dielectric layer. Sometimes diodes (PN, PIN, zener etc.) can be integrated on the same substrate with integrated passives specifically if the substrate is silicon or some other semiconductor like gallium arsenide (GaAs).\nDescription.\nIntegrated passive devices can be packaged, bare dies/chips or even stacked (assembled on top of some other bare die/chip) in a third dimension (3D) with active integrated circuits or other IPDs in an electronic system assembly. Typical packages for integrated passives are SIL (Standard In Line), SIP or any other packages (like DIL, DIP, QFN, chip-scale package/CSP, wafer level package/WLP etc.) used in electronic packaging. Integrated passives can also act as a module substrate, and therefore be part of a hybrid module, multi-chip module or chiplet module/implementation.\nThe substrate for IPDs can be rigid like ceramic (aluminumoxide/alumina), layered ceramic (low temperature co-fired ceramic/LTCC, high temperature co-fired ceramic/HTCC), glass, and silicon coated with some dielectric layer like silicon dioxide. The substrate can be also flexible like laminate e. g. a package interposer (called as an active interposer), FR4 or similar, Kapton or any other suitable polyimide. It is beneficial for the electronics system design if the effect of the substrate and the possible package to the performance of IPDs can be neglected or known.\nManufacturing of IPDs used include thick and thin film technologies and variety of integrated circuit processing steps or modifications (like thicker or different metals than aluminum or copper) of them. Integrated passives are available as standard components/parts or as custom designed (for a specific application) devices.\nApplications.\nIntegrated passive devices are mainly used as standard parts or custom designed due to\nThe challenge of custom IPDs compared to standard integrated or discrete passives however is the availability time for the assembly and sometimes also the performance. Depending on the manufacturing technology of integrated passives high capacitance or resistor values with a required tolerance may be hard to meet. Q value of coils/inductors might also be limited by the thickness of the metals available in the implementation. However new materials and improved manufacturing techniques like atomic layer deposition (ALD) and understanding manufacturing and control of thick metal alloys on large substrates improve capacitance density and Q value of coils/inductors. \nTherefore in prototyping and small/medium size production phase standard parts/passives are in many cases the fastest way to the realization. Custom designed passives can be considered to be used after careful technical and economical analysis in volume manufacturing, if time-to-market and cost targets of the product(s) can be met. Therefore integrated passive devices are continuously technically and economically challenged by decreasing size, improving tolerances, improving accuracy of assembly techniques (like SMT, surface-mount technology) of system motherboards and cost of discrete/separate passive devices. Going forward discrete and integrated passives will complement each other technically. Development and understanding of new materials and assembly techniques are a key enabler for both integrated and discrete passive devices.\nFabrication.\nIPDs on a silicon substrate.\nIPDs on a silicon substrate are generally fabricated using standard wafer fabrication technologies such as thin film and photolithography processing. For avoiding possible parasitic effects due to semiconductive silicon high resistive silicon substrate is typically used for integrated passives. IPDs on silicon can be designed as flip chip mountable or wire bondable components. However to differentiate technically from active integrated circuit (IC) technologies IPD technologies may utilise thicker metal (for higher Q value of inductors) or different resistive (like SiCr) layers, thinner or different higher K (higher dielectric constant) dielectric layers (like PZT instead of silicon dioxide or silicon nitride) for higher capacitance density than with typical IC technologies.\nIPDs on silicon can be grinded — if needed — below 100 µm in thickness and with many packaging options (micro-bumping, wire bonding, copper pads) and delivery mode options (as wafers, bare dies, tape & reel).\n3D passive integration in silicon is one of the technologies used to manufacture Integrated Passive Devices (IPDs), enabling high-density trench capacitors, metal-insulator-metal (MIM) capacitors, resistors, high-Q inductors, PIN, Schottky or Zener diodes to be implemented in silicon. The design time of IPDs on silicon depends on complexity of the design but can be made by using same design tools and environment what is used for application specific integrated circuits (ASICs) or integrated circuits. Some IPD suppliers offer full design kit support so that System in Package (SiP) module manufacturers or system houses are able to design their own IPDs fulfilling their specific application requirements.\nHistory.\nIn early control system design it was discovered that having same value of components makes design easier and faster. One way to implement passive components with same value or in practice with smallest possible distribution is to place them on the same substrate near to each other.\nEarliest form of integrated passive devices were resistor networks in the 1960s when four to eight resistors were packaged in form of Single-in-line package (SIP) by Vishay Intertechnology. Many other type of packages like DILs, DIPs etc. used in packaging integrated circuits even customised packages are used for integrated passive devices. Resistor, capacitor, and resistor capacitor networks are still widely used in systems even though monolithic integration has progressed.\nToday portable electronic systems include roughly 2–40 discrete passive devices/integrated circuit or module. This shows that monolithic or module integration is not capable to include all functionality based on passive components in system realisations, and variety of technologies is needed to minimize logistics and system size. This is the application area for IPDs. Most — by number — of the passives in electronic systems are typically capacitors followed by number of resistors and inductors/coils.\nMany functional blocks such as impedance matching circuits, harmonic filters, couplers and baluns and power combiner/divider can be realized by IPDs technology. IPDs are generally fabricated using thin, thick film and wafer fabrication technologies such as photolithography processing or typical ceramic technologies (LTCC and HTCC). IPDs can be designed as flip chip mountable or wire bondable components.\nTrends towards applications with small size, portability and wireless connectivity have stretched various implementation technologies to be able to realize passive components. In 2021, there were 25 - 30 companies delivering integrated passive (including simple passive networks and passives on various substrates like glass, silicon and alumina) devices worldwide.", "Engineering,_Manufacturing": 1.0000030994, "qwen": "Yes"}
{"id": "31320531", "revid": "41865877", "url": "https://en.wikipedia.org/wiki?curid=31320531", "title": "HMS Networks", "text": "HMS Networks AB is an international company in the field of Industrial Information and Communication Technology (Industrial ICT). HMS is headquartered in Halmstad, Sweden and is listed on the Nasdaq Nordic stock exchange, employing 700 people in 16 countries and with reported sales of 145 million Euro in 2020. HMS stands for \"Hardware Meets Software\" referring to the fact that HMS products allow industrial hardware to be connected to IoT software.\nProducts.\nHMS manufactures and markets industrial communication products that connect industrial devices to different industrial networks and IoT systems. HMS products act as translators between robots, control systems, motors, sensors, etc. and the different industrial networks that exists in the market (fieldbuses and Industrial Ethernet). HMS also offers a portfolio of wireless products as well as remote solutions for web-based control of field equipment such as PLCs, electric generators, machines, telecommunication base stations, building management systems and the likes.\nHMS markets products under the following brands:\nOrganization and history.\nHMS has operations in 16 countries: Sweden (Halmstad), Germany (Karlsruhe, Ravensburg, Wetzlar, Buchen), Belgium (Nivelles), Spain (Igualada, Barcelona), United States (Chicago, Boston), China (Beijing), Japan (Yokohama), The Netherlands (Hedel, Rotterdam), Italy (Milan, Brescia), France (Mulhouse), Romania (Sibiu), UK (Coventry, Manchester), Singapore, UAE (Dubai), South Korea (Seoul), India (Pune). In addition, distributors in 50 countries resell the HMS products on local markets.\nHMS was founded in 1988 by Nicolas Hassbjer and has been deemed \"Export Company of the Year\" by the Swedish Trade Council.", "Engineering,_Manufacturing": 0.9948464632, "qwen": "Yes"}
{"id": "31321967", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=31321967", "title": "Anodic bonding", "text": "Anodic bonding is a wafer bonding process to seal glass to either silicon or metal without introducing an intermediate layer; it is commonly used to seal glass to silicon wafers in electronics and microfluidics. This bonding technique, also known as field assisted bonding or electrostatic sealing, is mostly used for connecting silicon/glass and metal/glass through electric fields. The requirements for anodic bonding are clean and even wafer surfaces and atomic contact between the bonding substrates through a sufficiently powerful electrostatic field. Also necessary is the use of borosilicate glass containing a high concentration of alkali ions. The coefficient of thermal expansion (CTE) of the processed glass needs to be similar to those of the bonding partner.\nAnodic bonding can be applied with glass wafers at temperatures of 250 to 400 °C or with sputtered glass at 400 °C. Structured borosilicate glass layers may also be deposited by plasma-assisted e-beam evaporation.\nThis procedure is mostly used for hermetic encapsulation of micro-mechanical silicon elements. The glass substrate encapsulation protects from environmental influences, e.g. humidity or contamination. Further, other materials are used for anodic bonding with silicon, i.e. low-temperature cofired ceramics (LTCC).\nOverview.\nAnodic bonding on silicon substrates is divided into bonding using a thin sheet of glass (a wafer) or a glass layer that is deposited onto the silicon using a technique such as sputtering. The glass wafer is often sodium-containing Borofloat or Pyrex glasses. With an intermediate glass layer, it is also possible to connect two silicon wafers. The glass layers are deposited by sputtering, spin-on of a glass solution or vapor deposition upon the processed silicon wafer. The thickness of these layers range from one to a few micrometers with spin-on glass layers needing 1 µm or less. Hermetic seals of silicon to glass using an aluminum layer with thickness of 50 to 100 nm can reach strengths of 18.0 MPa. This method enables burying electrically isolated conductors in the interface. Bonding of thermally oxidized wafers without a glass layer is also possible.\nThe procedural steps of anodic bonding are divided into the following:\nwith a process characterized by the following variables:\nThe typical bond strength is between 10 and 20 MPa according to pull tests, higher than the fracture strength of glass.\nDiffering coefficients of thermal expansion pose challenges for anodic bonding. Excessive mismatch can harm the bond through intrinsic material tensions and cause disruptions in the bonding materials. The use of sodium-containing glasses, e.g. Borofloat or Pyrex, serve to reduce the mismatch. These glasses have a similar CTE to silicon in the range of applied temperature, commonly up to 400 °C.\nHistory.\nAnodic bonding is first mentioned by Wallis and Pomerantz in 1969. It is applied as bonding of silicon wafers to sodium containing glass wafers under the influence of an applied electric field. This method is used up to date as encapsulation of sensors with electrically conducted glasses.\nProcedural steps of anodic bonding.\nPretreatment of the substrates.\nThe anodic bonding procedure is able to bond hydrophilic and hydrophobic silicon surfaces equally effectively. The roughness of the surface should be less than 10 nm and free of contamination on the surface for the procedure to work properly. Even though anodic bonding is relatively tolerant to contaminations, a widely established cleaning procedure RCA takes place to remove any surface impurities.\nThe glass wafer can also be chemically etched or powder blasted for creating small cavities, where MEMS devices can be accommodated.\nFurther mechanisms supporting the bonding process of not completely inert anodic materials can be the planarization or polishing of surfaces and the ablation of the surface layer by electrochemical etching.\nContact the substrates.\nThe wafers that meet the requirements are put into atomic contact. As soon as contact is first established, the bonding process starts close to the cathode and spreads in fronts to the edges, the process taking several minutes.\nThe anodic bonding procedure is based on a glass wafer that is usually placed above a silicon wafer. An electrode is in contact with the glass wafer either through a needle or a full area cathode electrode.\nIf using a needle electrode, the bond spreads radially to the outside which makes it impossible to trap air between the surfaces. The radius of the bonded area is approximately proportional to the square root of time elapsed during the procedure. Below temperatures of 350 to 400 °C and a bond voltage of 500 to 1000 V, this method is not very effective nor reliable.\nThe use of a full area cathode electrode shows bond reactions over the whole interface after powering up the potential. This is the result of a homogeneous electric field distribution at temperatures of around 300 °C and bond voltage of 250 V. Using thin deposited glass layers the voltages needed can be significantly reduced.\nHeating and bonding by application of electrostatic field.\nThe wafers are placed between the chuck and the top tool used as bond electrode at temperatures between 200 and 500 °C (compare to image \"scheme of anodic bonding procedure\") but below the softening point of glass (glass transition temperature). The higher the temperature the better is the mobility of positive ions in glass.\nThe applied electrical potential between is set to a voltage of several 100 V. This causes a diffusion of sodium ions (Na+) out of the bond interface to the backside of the glass to the cathode. That results, combined with humidity in formation of NaOH. High voltage helps to support the drifting of the positive ions in glass to the cathode. The diffusion is according to the Boltzmann distribution exponentially related to the temperature. The glass (NaO2) with its remaining oxygen ions (O2−) is negatively volume charged at the bonding surface compared to the silicon (compare to figure \"ion drifting in bond glass\" (1)). This is based on the depletion of Na+ ions.\nSilicon is unlike, e.g. aluminium, an inert anode. In result no ions drift out of the silicon into the glass during the bond process. This affects a positive volume charge in the silicon wafer on the opposite side. As a result, a few micrometer thick high-impedance depletion region is developed at the bond barrier in the glass wafer. In the gap between silicon and glass the bond voltage drops. The bond process as a combination of electrostatic and electrochemical process starts.\nThe electrical field intensity in the depletion region is so high that the oxygen ions drift to the bond interface and pass out to react with the silicon to form SiO2 (compare to figure \"ion drifting in bond glass\" (2)). Based on the high field intensity in the depletion region or in the gap at the interface, both wafer surfaces are pressed together at a specific bond voltage and bond temperature. The process is realized at temperatures from 200 - 500 °C for about 5 to 20 min. Typically, the bonding or sealing time becomes longer when temperature and voltage are reduced. The pressure is applied to create intimate contact between the surfaces to ensure good electrical conduction across the wafer pair. This ensures intimate contact for the surfaces of the bonding partners. The thin formed oxide layer between the bond surfaces, siloxane (Si-O-Si), ensures the irreversible connection between the bonding partners.\nIf using thermally oxidized wafers without a glass layer, the diffusion of OH− and H+ ions instead of Na+ ions leads to the bonding.\nCooling down the substrate.\nAfter the bonding process, slow cooling over several minutes has to take place. This can be supported by purging with an inert gas. The cooling time depends on the difference of CTE for the bonded materials: the higher the CTE difference, the longer the cooling period.", "Engineering,_Manufacturing": 1.0000021458, "qwen": "Yes"}
{"id": "31325232", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=31325232", "title": "Resealable packaging", "text": "Resealable packaging is any type of packaging that allows the consumer or user to reseal or reclose the packaging. Often packaging needs to be resealed in order to maintain product freshness or prevent spillage. Reusable packaging allows for multiple uses which can help reduce waste.", "Engineering,_Manufacturing": 0.9998086095, "qwen": "Yes"}
{"id": "31331135", "revid": "1161011960", "url": "https://en.wikipedia.org/wiki?curid=31331135", "title": "Wafer bonding", "text": "Wafer bonding is a packaging technology on wafer-level for the fabrication of microelectromechanical systems (MEMS), nanoelectromechanical systems (NEMS), microelectronics and optoelectronics, ensuring a mechanically stable and hermetically sealed encapsulation. The wafers' diameter range from 100 mm to 200 mm (4 inch to 8 inch) for MEMS/NEMS and up to 300 mm (12 inch) for the production of microelectronic devices. Smaller wafers were used in the early days of the microelectronics industry, with wafers being just 1 inch in diameter in the 1950s.\nOverview.\nIn microelectromechanical systems (MEMS) and nanoelectromechanical systems (NEMS), the package protects the sensitive internal structures from environmental influences such as temperature, moisture, high pressure and oxidizing species. The long-term stability and reliability of the functional elements depend on the encapsulation process, as does the overall device cost. The package has to fulfill the following requirements:\nTechniques.\nThe commonly used and developed bonding methods are as follows:\nRequirements.\nThe bonding of wafers requires specific environmental conditions which can generally be defined as follows:\nThe actual bond is an interaction of all those conditions and requirements. Hence, the applied technology needs to be chosen in respect to the present substrate and defined specification like max. bearable temperature, mechanical pressure or desired gaseous atmosphere.\nEvaluation.\nThe bonded wafers are characterized in order to evaluate a technology's yield, bonding strength and level of hermeticity either for fabricated devices or for the purpose of process development. Therefore, several different approaches for the bond characterization have emerged. On the one hand non-destructive optical methods to find cracks or interfacial voids are used beside destructive techniques for the bond strength evaluation, like tensile or shear testing. On the other hand, the unique properties of carefully chosen gases or the pressure depending vibration behavior of micro resonators are exploited for hermeticity testing.", "Engineering,_Manufacturing": 0.9980040789, "qwen": "Yes"}
{"id": "31336127", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=31336127", "title": "Eutectic bonding", "text": "Eutectic bonding, also referred to as eutectic soldering, describes a wafer bonding technique with an intermediate metal layer that can produce a eutectic system. Those eutectic metals are alloys that transform directly from solid to liquid state, or vice versa from liquid to solid state, at a specific composition and temperature without passing a two-phase equilibrium, i.e. liquid and solid state. The fact that the eutectic temperature can be much lower than the melting temperature of the two or more pure elements can be important in eutectic bonding. \nEutectic alloys are deposited by sputtering, dual source evaporation or electroplating. They can also be formed by diffusion reactions of pure materials and subsequently melting of the eutectic composition.\nEutectic bonding to transfer epitaxial materials such as GaAs-AlGaAs onto Si substrates with a high degree of success, for the general purpose of optoelectronics integration with Si electronics as well as to overcome fundamental issues such as lattice mismatch in hetero-epitaxy, was developed and reported by Venkatasubramanian et al. in 1992. The device performance validation of such eutectic metal bonded GaAs-AlGaAs materials for solar cells were further reported by Venkatasubramanian et al. in 1994. Eutectic bonding is able to produce hermetically sealed packages and electrical interconnection within a single process (compare ultrasonic images). In addition this procedure is conducting at low processing temperatures, low resultant stress induced in final assembly, high bonding strength, large fabrication yield and a good reliability. Those attributes are dependent on the coefficient of thermal expansion between the substrates.\nThe most important parameters for eutectic bonding are:\nOverview.\nEutectic bonding is based on the ability of silicon (Si) to alloy with numerous metals and form a eutectic system. The most established eutectic formations are Si with gold (Au) or with aluminium (Al). This bonding procedure is most commonly used for Si or glass wafers that are coated with an Au/Al film and partly with adhesive layer (compare with following image).\nThe Si-Au couple has the advantages of an exceptionally low eutectic temperature, an already widespread use in die bonding and the compatibility with Al interconnects. Additionally, often used eutectic alloys for wafer bonding in semiconductor fabrication are shown in the table. Choosing the correct alloy is determined by the processing temperature and compatibility of the materials used.\nFurther, the bonding has less restrictions, concerning substrate roughness and planarity than direct bonding. Compared to anodic bonding, no high voltages are required that can be detrimental to electrostatic MEMS. Additionally, the eutectic bonding procedure promotes a better out-gassing and hermeticity than bonding with organic intermediate layers. Compared to glass frit bonding, the advantage sticks out that the reduction of seal ring geometries, an increase of the hermeticity levels and a shrinking of device size is possible. The geometry of eutectic seals is characterized by a thickness of 1 - 5 µm and a wideness of > 50 µm. The use of eutectic alloy brings the advantage of providing electrical conduction and interfacing with redistribution layers.\nThe temperature of the eutectic bonding procedure is dependent on the used material. The bonding happens at a specific weight-% and temperature, e.g. 370 °C at 2.85 wt-% Si for Au intermediate layer (compare to phase diagram).\nThe procedure of eutectic bonding is divided into following steps:\nProcedural steps.\nPre-treatment.\nThe surface preparation is the most important step to accomplish a successful eutectic bonding. This bonding procedure is due to oxide presence on the silicon substrates very limited based on the poor wettability of Au on the oxide layer. This leads to a poor adhesion of the eutectic bond. The oxide on the silicon surface acts as a diffusion barrier. The surface preparation's main task is to facilitate the deposition of the eutectic metal by oxide removal or adhesion layer deposition.\nTo remove existing native oxide layers wet chemical etching (HF clean), dry chemical etching or chemical vapor deposition (CVD) with different types of crystals can be used. Also some applications require a surface pre-treatment using dry oxide removal processes, e.g. H2 plasma and CF4 plasma.\nAn additional method for the removal of unwanted surface films, i.e. oxide, is applying ultrasound during attachment process. As soon the tool is lowered a relative vibration between the wafer and the substrate is applied. Commonly, industrial bonders use ultrasonic with 60 Hz vibration frequencies and 100 µm vibration amplitude. A successful oxide removal results in a solid, hermetically tight connection.\nA Second method to ensure the eutectic metal adheres on the Si wafer is by using an adhesion layer. This thin intermediate metal layer adheres well to the oxide and the eutectic metal. Well suitable metals for an Au-Si compound are titanium (Ti) and chromium (Cr) resulting in, e.g. Si-SiO2-Ti-Au or Si-SiO2-Cr-Au. The adhesion layer is used to break up the oxide by diffusion of silicon into the used material. A typical wafer is composed of a silicon wafer with oxide, 30 - 200 nm Ti or Cr layer and Au layer of > 500 nm thickness.\nIn the wafer fabrication a nickel (Ni) or a platinum (Pt) layer is added between the gold and the substrate wafer as diffusion barrier. The diffusion barrier avoids interaction between Au and Ti/Cr and requires higher temperatures to form a reliable and uniform bond. Further, the very limited solubility of silicon in titanium and chromium can prevent the developing of Au-Si eutectic composition based on the diffusion of silicon through titanium into gold.\nThe eutectic materials and optional adhesion layers are usually approached by deposition as alloy in one layer by dual component electroplating, dual-source evaporation (physical vapor deposition) or composite alloy sputtering.\nThe removal of contamination, on the for silicon most established Au layer, is usually realized with water flushing and wafer heating.\nBonding process.\nThe contacting of the substrates is applied directly after the pre-treatment of the surfaces to avoid oxide regeneration. The bonding procedure for oxidizing metals (not Au) generally takes place in a reduced atmosphere of 4% hydrogen and an inert carrier gas flow, e.g. nitrogen. The requirements for the bonding equipment lies in the thermal and pressure uniformity across the wafer. This enables uniformly compressed seal lines.\nThe substrate is aligned and fixed on a heated stage and the silicon wafer in a heated tool. The substrates inserted in the bonding chamber are contacted maintaining the alignment. As soon the layers are in atomic contact the reaction between those starts. To support the reaction mechanical pressure is applied and heating above the eutectic temperature is carried out.\nThe diffusivity and solubility of gold into silicon substrate increases with rising bonding temperatures. A higher temperature than the eutectic temperature is usually preferred for the bonding procedure. This may result in the formation of a thicker Au-Si alloy layer and further a stronger eutectic bond.\nThe diffusion starts as soon as the layers are in atomic contact at elevated temperatures. The contacted surface layer containing the eutectic composites melts, forming a liquid phase alloy, accelerating further mixing processes and diffusion until the saturation composition is reached.\nOther common eutectic bonding alloys commonly used for wafer bonding include Au-Sn, Al-Ge, Au-Ge, Au-In and Cu-Sn.\nThe chosen bonding temperature usually is some degrees higher than the eutectic temperature so the melt becomes less viscous and readily flows due to higher roughness to surface areas that are not in atomic contact. To prevent the melt pressed outside the bonding interface the optimization of the bonding parameter control is necessary, e.g. low force on the wafers. Otherwise, it may lead to short circuits or device malfunctions of the used components (electrical and mechanical). The heating of the wafers leads to a change in the surface texture due to formation of fine silicon micro structures on top of the gold surface.\nCooling process.\nThe material mix is solidified when the temperature decreases below eutectic point or the concentration ratio changes (for Si-Au: ). The solidification leads to epitaxial growth of silicon and gold on top of the silicon substrate resulting in numerous small silicon islands protruding from a polycrystalline gold alloy (compare to cross-section image of the bonding interface). This can result in bonding strengths around 70 MPa.\nThe importance lies in the appropriate process parameters, i.e. sufficient bonding temperature control. Otherwise the bond cracks due to stress caused by a mismatch of the thermal expansion coefficient. This stress is able to relax over time.\nExamples.\nBased on the high bonding strength this procedure is special applicable for pressure sensors or fluidics. Also smart micro mechanical sensors and actuators with electronic and/or micro mechanical functions over multiple wafers can be fabricated.", "Engineering,_Manufacturing": 0.9998387098, "qwen": "Yes"}
{"id": "31336130", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=31336130", "title": "Glass frit bonding", "text": "Glass frit bonding, also referred to as glass soldering or seal glass bonding, describes a wafer bonding technique with an intermediate glass layer. It is a widely used encapsulation technology for surface micro-machined structures, e.g., accelerometers or gyroscopes. This technique utilizes low melting-point glass (\"glass solder\") and therefore provides various advantages including that viscosity of glass decreases with an increase of temperature. The viscous flow of glass has effects to compensate and planarize surface irregularities, convenient for bonding wafers with a high roughness due to plasma etching or deposition. A low viscosity promotes hermetically sealed encapsulation of structures based on a better adaption of the structured shapes. Further, the coefficient of thermal expansion (CTE) of the glass material is adapted to silicon. This results in low stress in the bonded wafer pair. The glass has to flow and wet the soldered surfaces well below the temperature where deformation or degradation of either of the joined materials or nearby structures (e.g., metallization layers on chips or ceramic substrates) occurs. The usual temperature of achieving flowing and wetting is between .\nGlass frit bonding can be used for many surface materials, e.g., silicon with hydrophobic and hydrophilic surface, silicon dioxide, silicon nitride, aluminium, titanium or glass, as long as the CTE are in the same range. This bonding procedure also allows the realization of metallic feedthroughs to contact active structures in the hermetically sealed cavity. Glass frit as a dielectric material does not need additional passivation for preventing leakage currents at process temperatures up to .\nThe process begins with the deposition of glass paste onto the surfaces to be treated. It is then heated to burn out additives and fire it in order to form the glass layer. The bonding process reconfigures the sintered glass into the desired state. Finally, the reconfigured glass is cooled down.\nGlass frit bonding is used to encapsulate surface micro-machined sensors, i.e. gyroscopes and accelerometers. Other applications are the sealing of absolute pressure sensor cavities, the mounting of optical windows and the capping of thermally active devices.\nProcedure.\nDeposition.\nThe glass frit bond procedure is used for the encapsulation and mounting of components. The coating of glass frit layers is applied by spin coating for thickness of 5 to 30 μm or commonly by screen printing for thickness of 10 to 30 μm.\nScreen printing, as a commonly used deposition method, provides a technique of structuring for the glass frit material. This method has the advantage of material deposition on structured cap wafers without any additional processes, i.e. photolithography.\nScreen printing enables the possibility of selective bonding. So only in areas where bonding is required the glass frit is deposited.\nThe risk of glass frit flowing into the structures can be prevented by optimization of the screen printing process. Under high positioning precision the sizes of the structures in the range of 190 μm with a minimum spacing of wettability of the printed surface, 10 to 20% wider than the designed screen.\nTo ensure a uniform glass thickness, all structures should have the same width. The printed glass frit high is about 30 μm and provides a gap of 5 to 10 μm between the bonded wafers after bonding (compare to cross sectional SEM images). A bond surface activation is not necessary to promote a higher bonding strength.\nThermal conditioning.\nThe printed glass frit structures are heated to form compact glass. The heating process is necessary to drive out the solvents and binder. This results in a subsequent particle fusion of the glass powder. Using mechanical pressure the wafers are bonded at elevated temperatures.\nThermal conditioning transforms the glass paste into a glass layer and is important to prevent voids inside the glass frit layer. The conditioning process consists of:\nThe initial step comprises drying for 5 to 7 minutes at 100 to 120 °C in order to diffuse solvents out of the interface. This starts the polymerization of the organic binder. The binder molecules are linked to long-chain polymers what solidifies the paste.\nThe organic binder of the glass paste has to be burned with heating up to a specific temperature (325 to 350 °C) where the glass is not fully melted for 10 to 20 minutes. This so-called glazing ensures the outgassing of the organic additives.\nFurther, a pre-melting or sealing step heats the material to the process temperature between 410 and 459 °C for 5 to 10 min. The material fully melts and forms a compact glass without any inclusions. The inorganic fillers are melted down and the properties of the bond glass are fixed. The melting of the glass starts at the silicon-glass interface directed to the glass surface. During the melting process the porosity of the glass eliminates and based on the compression of the intermediate layer the thickness of the glass decreases significantly.\nBonding process.\nThe glass frit bonding, starting with alignment of the wafers, is a thermo-compressive process that takes place in the bonding chamber at specific pressure. Under bonding pressure wafers are heated up to the process temperature around 430 °C for a few minutes. On the one hand a short bonding time causes the glass frit to spread insufficiently, on the other hand a longer bonding time causes the glass frit to be overflown subsequently leaving voids.\nThe alignment has to be very precise and stable to prevent shifting. This can be realized using clamps or special pressure plates. Shifting can occur through temporarily staggered pressure, not precise vertical pressure based on misalignment of the bonding tools or the difference of thermal expansion between the bonding tools.\nDuring bonding a supporting tool pressure is applied to improve the thermal input into the bonding glass and equal wafer geometry inadmissibility (i.e. bow and warp) supporting wettability. Based on the sufficiently high viscosity of the glass, bonding can take place nearly without pressure.\nThe bonding temperature needs to be high enough to reduce the viscosity of the glass material and ensures a good wetting of the bond surface, but also low enough to prevent overspreading of the glass frit material. The heating up over 410 °C enables the wetting of the bond surface. A good wetting is indicated by a low edge angle. The atomic wafer surface layers are fused into the glass at an atomic level. This forms a thin glass mixture at the interface which forms the strong bond between the glass and the wafer.\nCooling.\nDuring cooling down under pressure a mechanically strong and hermetically sealed wafer bond is formed. The cooling process leads especially at higher temperatures to thermal stress in the glass frit layer that has to be considered in the lifetime analysis of the bond frame. The wafer pair is removed from the bond chamber at lower temperatures to prevent thermal cracking of the wafers or the bond interface by thermal shocks.\nThe bonding strength is mainly dependent on the density, the spreading area of the glass frit layer and the surface layer of the bonding interface. It is high enough, around 20 MPa, for most applications and comparable to those achieved with anodic bonding. The hermeticity ensures the correct function and a sufficient reliability of the bond and therefore the product. Further, the bonding yield of glass frit bonded wafers is very high, normally > 90 %.\nTypes.\nTwo types of glass solders are used: vitreous, and devitrifying. Vitreous solders retain their amorphous structure during remelting, can be reworked repeatedly, and are relatively transparent. Devitrifying solders undergo partial crystallization during solidifying, forming a glass-ceramic, a composite of glassy and crystalline phases. Devitrifying solders usually create a stronger mechanical bond, but are more temperature-sensitive and the seal is more likely to be leaky; due to their polycrystalline structure they tend to be translucent or opaque. Devitrifying solders are frequently \"thermosetting\", as their melting temperature after recrystallization becomes significantly higher; this allows soldering the parts together at lower temperature than the subsequent bake-out without remelting the joint afterwards. Devitrifying solders frequently contain up to 25% zinc oxide. In production of cathode ray tubes, devitrifying solders based on PbO-B2O3-ZnO are used.\nVery low temperature melting glasses, fluid at , were developed for sealing applications for electronics. They can consist of binary or ternary mixtures of thallium, arsenic and sulfur. Zinc-silicoborate glasses can also be used for passivation of electronics; their coefficient of thermal expansion must match silicon (or the other semiconductors used) and they must not contain alkaline metals as those would migrate to the semiconductor and cause failures.\nThe bonding between the glass or ceramics and the glass solder can be either covalent, or, more often, van der Waals. The seal can be leak-tight; glass soldering is frequently used in vacuum technology. Glass solders can be also used as sealants; a vitreous enamel coating on iron lowered its permeability to hydrogen 10 times. Glass solders are frequently used for glass-to-metal seals and glass-ceramic-to-metal seals.\nProduction.\nGlass solders are available as frit powder with grain size below 60 micrometers. They can be mixed with water or alcohol to form a paste for easy application, or with dissolved nitrocellulose or other suitable binder for adhering to the surfaces until being melted. The eventual binder has to be burned off before melting proceeds, requiring careful firing regime. The solder glass can be also applied from molten state to the area of the future joint during manufacture of the part. Due to their low viscosity in molten state, lead glasses with high PbO content (often 70–85%) are frequently used. The most common compositions are based on lead borates (leaded borate glass or borosilicate glass). Smaller amount of zinc oxide or aluminium oxide can be added for increasing chemical stability. Phosphate glasses can be also employed. Zinc oxide, bismuth trioxide, and copper(II) oxide can be added for influencing the thermal expansion; unlike the alkali oxides, these lower the softening point without increasing of thermal expansion.\nTo achieve process temperatures beneath 450 °C leaded glass or lead silicate glass is used. The glass frit is a paste consisting glass powder, organic binder, inorganic fillers and solvents. This low melting glass paste is milled into powder (grain size cordierite particles (e.g. Mg2Al3 [AlSi5O18]) or barium silicate, are added to the melted glass paste to influence properties, i.e. lowering the mismatch of thermal expansion coefficients between silicon and glass frit. The solvents are used to adjust the viscosity of the organic binder. Several glass frit pastes are commercially available, e.g. FERRO FX-11-0366, and every single one need individual handling after deposition. The choice of the paste depends on various factors, i.e. deposition method, substrate material and process temperatures.\nThe glass used for MEMS applications consists of particles and lead oxide. Latter lowers the glass transition temperature below 400 °C. The reduction of lead oxide by the silicon leads to the formation of lead precipitations at the silicon-glass interface. Those precipitations decrease the strength of the bond and are reliability risks that have to be considered for the lifetime predictions of the devices.\nUses.\nGlass solders are frequently used in electronic packaging. CERDIP packagings are an example. Outgassing of water from the glass solder during encapsulation was a cause of high failure rates of early CERDIP integrated circuits. Removal of glass-soldered ceramic covers, e.g., for gaining access to the chip for failure analysis or reverse engineering, is best done by shearing; if this is too risky, the cover is polished away instead.\nAs the seals can be performed at much lower temperature than with direct joining of glass parts and without use of flame (using a temperature-controlled kiln or oven), glass solders are useful in applications like subminiature vacuum tubes or for joining mica windows to vacuum tubes and instruments (e.g., Geiger tube). Thermal expansion coefficient has to be matched to the materials being joined and often is chosen in between the coefficients of expansion of the materials. In case of having to compromise, subjecting the joint to compression stresses is more desirable than to tensile stresses. The expansion matching is not critical in applications where thin layers are used on small areas, e.g., fireable inks, or where the joint will be subjected to a permanent compression (e.g., by an external steel shell) offsetting the thermally introduced tensile stresses.\nGlass solder can be used as an intermediate layer when joining materials (glasses, ceramics) with significantly different coefficient of thermal expansion; such materials cannot be directly joined by diffusion welding. Evacuated glazing windows are made of glass panels soldered together.\nA glass solder is used, e.g., for joining together parts of cathode ray tubes and plasma display panels. Newer compositions lowered the usage temperature from by reducing the lead(II) oxide content down from 70%, increasing the zinc oxide content, adding titanium dioxide and bismuth(III) oxide and some other components. The high thermal expansion of such glass can be reduced by a suitable ceramic filler. Lead-free solder glasses with soldering temperature of were also developed.\nPhosphate glasses with low melting temperature were developed. One of such compositions is phosphorus pentoxide, lead(II) oxide, and zinc oxide, with addition of lithium and some other oxides.\nElectrically conductive glass solders can be also prepared.\nAdvantages.\nThe following advantages result from using the glass frit bonding procedure:", "Engineering,_Manufacturing": 0.9998897314, "qwen": "Yes"}
{"id": "31336137", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=31336137", "title": "Reactive bonding", "text": " Reactive bonding describes a wafer bonding procedure using highly reactive nanoscale multilayer systems as an intermediate layer between the bonding substrates. The multilayer system consists of two alternating different thin metallic films. The self-propagating exothermic reaction within the multilayer system contributes the local heat to bond the solder films. Based on the limited temperature the substrate material is exposed, temperature-sensitive components and materials with different CTEs, i.e. metals, polymers and ceramics, can be used without thermal damage.\nOverview.\nThe bonding is based on reactive nano scale multilayers providing an internal heat source. These foils are combined with additional solder layers to achieve bonding. The heat that is required for the bonding is created by a self-propagating exothermic reaction of the multilayer system. This reaction is ignited by an energy pulse, i.e. temperature, mechanical pressure, electrical spark or laser pulse. The generated heat is localized to the bonding interface and limited due to a short term heating phase within milliseconds.\nThis heat is an advantage of this approach, so the used materials are not exposed to high temperatures and allow rapid cooling. A drawback is that this approach is not applicable for bond frame dimensions of few ten micrometres. This is based on the limited handling and structuring abilities of the foils at this small dimensions.\nThe material used for multilayer systems is a bilayer of alternating elements, commonly Ni/Al, Al/Ti or Ti/a-Si. The metallic layer is usually 1 to 30 nm thick and can be arranged as horizontal or vertical nano scale material films and are a combination of a reactive and a low melting component. With increased bilayer thickness, the reaction velocity decreases and the reaction heat increases. Therefore, a specific balance between high reaction velocity and high reaction heat is necessary.\nA commercial example of such material is NanoFoil. The corresponding bonding process is known as NanoBond.\nPreprocessing.\nTwo different reactive structures are established, conventional lateral layer-by-layer (multilayer) and vertical arranged structures. Based on difficulties, that occur during handling, patterning and positioning of the freestanding foils, the multilayer films are directly deposited onto the silicon substrate. The deposition of the multilayer systems on silicon is achieved by magnetron sputtering, electroplating or etching. The vertical nano structures are also created directly on the substrate surface.\nThe substrate surfaces are deposited with a solder layer, i.e. gold (Au), using physical vapor deposition (PVD). The PVD process promotes the wetting of the solder. The intermixing of the used components during deposition influences the reaction parameters and to prevent this the substrates are cooled.\nA commonly used deposition method for multilayer structures is magnetron sputtering. A multilayer system consists of thousands of thin single layers of the component combination that are alternately sputtered on the substrate surface.\nFor electroplating or electrochemical deposition (ECD) multilayer deposition two approaches are established. On the one hand a two bath method exist, which means an alternating deposition in two different plating baths. On the other hand, a one bath method, with an electrolyte containing both film components in one bath, can be used. The ECD process reduces process time and complexity. In addition, this method enables pattern plating to prevent complex etching process of structures.\nVertical nanostructures are created in two steps. At first, needles in the silicon substrate are created by dry etching. The other used material is deposited using sputtering to cover those needles. This approach reduces the process time and complexity drastically due to the deposition omission of the thousands of single layers. Further, reactive foil patterning can be realized by applying an electrochemical machining process.\nBonding.\nThe bonding process is based on the reaction of the nanoscale multilayer to release energy concentrated at the interface. The self-propagating reaction is caused by the reduction of chemical bond energy in the multilayer system (compare to figure \"Schematic self-propagating reaction in a multilayer system after ignition\").\nThe system alloy, or an intermetallic compound, (AB) is formed from the intermixing elements (A+B) due to atomic diffusion.\nThe reactive foil is ignited by an energy pulse resulting in an immediate self-propagating reaction (compare to figure \"Schematic reactive bonding process with a reactive multilayer as heat source\").\nThis local intermixing process produces heat that is transmitted to the adjacent element layers. The reaction spreads through the foil in milliseconds. This energy release leads to a high temperature in the bonding interface. Meanwhile, the components outside the interface are not exposed to the high temperatures of the reaction. Besides the high interface energy, this reaction is also promoted by the low thickness and therefore the reduced diffusion path of the single metallic layers.\nThe resulting internal heat melts the solder layers to form a bond with the multilayer system and the substrate based on diffusion. This exothermic reaction can be ignited in reactive materials like compacted powders, e.g. Ni/Ti or Ti/Co, as well as in nanostructured multilayer systems, e.g. Ni/Al. The bonding can take place in various environments, i.e. vacuum, with a force providing a defined mechanical pressure at room temperature. A high applied mechanical pressure enhances the solder flow and therefore can improve the wetting of the substrate.\nExamples.\nReactive bonding approach is used to assemble MEMS components including die attachment and the hermetic sealing of micro-system packages. The process is used to join temperature sensitive biological activated substrates for diagnostics or medical devices. In addition disposable microfluidic devices with sensing function and immobilized cells can be fabricated.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "37070715", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=37070715", "title": "Cap torque tester", "text": "The cap torque tester is used in the packaging industry to measure the opening or closing torque of the screwing cap. It is a piece of specific quality control equipment that can be placed on the production line or in the laboratory.\nPackaging development.\nA torque tester is required during the packaging design process. It can be used as a destructive tester to identify if there is any material weakness of the packaging during the screwing process. It also allows one to define the torque tolerances of the capping machine. The lower torque limit is considered the minimum pressure of the cap to avoid any leak of the product. This torque test needs to be combined with a leak test with secure seal analyzer. The higher torque limit is the maximum torque the customer can apply to open or close the product's cap.\nProduction line control.\nOnce torque tolerances have been defined, the cap torque tester is used as a torque control device on the final product. If measurements are out of the limits, the capping machine needs to be adjusted. Depending on the production process, it could be necessary to control the opening torque, 24 hours after the packaging process. Temperature variations can modify product characteristics with a result of different torque measurement.", "Engineering,_Manufacturing": 0.9998440742, "qwen": "Yes"}
{"id": "33794374", "revid": "1159159714", "url": "https://en.wikipedia.org/wiki?curid=33794374", "title": "Apple Daisy Wheel Printer", "text": "The Apple Daisy Wheel Printer is a daisy wheel printer manufactured by Qume and sold by Apple Computer, Inc. in the 1980s. It utilized the ASCII character set and used continuous form paper, or with an optional feeder, cut sheet paper. The printer included several different 130-character \"daisy\" print wheels (e.g., Courier, Prestige Elite, Gothic, Executive) in English, French, German, and other languages. These 130-character print wheels are unique to the Apple DWP; the standard Qume printwheel has 96 characters. \nIt could be used with the Lisa system, Apple III system, and Apple IIe or Apple II Plus system if the Super Serial Interface Card was installed.\nWhen used with the Lisa, the printer could produce simple graphics by microstepping the print head and using the period, pipe ( | ), and slash characters. The period is reinforced with brass to prevent it wearing out.\nThis printer is also referred to as the Apple Letter Quality printer.", "Engineering,_Manufacturing": 0.9353882074, "qwen": "Yes"}
{"id": "33803593", "revid": "7178531", "url": "https://en.wikipedia.org/wiki?curid=33803593", "title": "Institut für Integrierte Produktion Hannover", "text": "Institut für Integrierte Produktion Hannover (IPH), which literally translates as \"Hanover institute of integrated production\", is a non-profit limited company providing research and development, consulting, and training in industrial engineering.\nHistory.\nOn January 1, 1988, three German engineering professors founded IPH as a spin-off company of Leibniz University Hannover. As the non-profit company dealt with computer-integrated manufacturing, it was originally called “CIM-Fabrik Hannover” (CIM factory of Hanover). The name was later changed to IPH – Institut für Integrierte Produktion Hannover.\nIn 1991, the company and its 26 employees moved from the inner city to “Wissenschaftspark” in Marienwerder, in the Northwest of Hanover. To create room for an increasing number of employees, the company building was extended just eight years later.\nThe death of professor Eckart Doege, co-founder and managing partner of the IPH, in 2004 marked the end of an era. Bernd-Arno Behrens, professor of forming at Leibniz University Hannover, was appointed as his successor. Co-founders professor Hans Kurt Toenshoff and professor Hans-Peter Wiendahl left the company in 2007 resp. 2008. They were succeeded by two professors of Leibniz University Hannover: Ludger Overmeyer, professor of automation engineering, and Peter Nyhuis, professor of production systems and logistics.\nThe change of the management board led to a strategic transformation of research topics. In addition to logistics, production automation, and process technology, xxl goods was added to the IPH portfolio as another research topic. The research engineers apply the term xxl goods to products such as planes, ships, wind energy plants but also motor parts of utility vehicles, and jet engines. The company’s aim is to promote research dealing with the production of these large scale goods. Currently, IPH is the only research institute exploring this theme from a scientific point of view.\nOrganization.\nThe company is composed of three departments focusing on logistics, production automation, and process technology. Research dealing with xxl goods is done by all departments.\nIPH is run by three managing partners and a managing director. As a non-profit research company, it is funded by public research funding but also by the money earned through industry consulting.\nBusiness activities.\nThe IPH offers Research and development, consulting, and training in production engineering. Customers range from local small and medium-sized businesses to multinational companies.\nFields of activity include:\nProcess technology.\nSince 2000 the IPH has been part of the special research field dealing with flashless precision forging (“Sonderforschungsbereich 489”). Funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG), this consortium conducts research on the process chain of high-performance parts forged without flash. According to Doege et al., the term “flashless precision forging” is commonly used in two ways: On the one hand, it describes forging without flash. On the other hand, it is used for forged parts with a tolerance of IT 7 to IT 9. Latest research findings indicate that it is possible to forge complicated parts, such as crankshafts, without flash. In order to forge crankshafts without flash, appropriate preforming processes are necessary. At IPH, the main focus is on multi-directional forging and cross wedge rolling.\nIPH engineers also conduct research on cross wedge rolling within the context of process chain design of warm forging. The influence of temperature on both the process and part quality is studied for cross wedge rolling and forge rolling. Also, wearing of forging tools is investigated. A recent approach to reduce wear is the coating of parts with layers of DLC.\nFurther research efforts include hydro forming (e.g. of titanium). In this context, material and composite material are studied. “Tailored hybrid tubes” is another research area about to be investigated. The term describes material combined of both steel and aluminum.\nA new way of forging developed by IPH is hybrid forging. This technique combines both forging and joining of massive parts and sheet metal in one single operation.\nAnother development fostered by IPH is a module for automatized stud welding with tip ignition that is integrated into sheet metal working tools. This development reduces the process chain significantly. As a result, costs of extra positioning units and time needed for positioning are cut.\nIn the field of sheet metal forming, efforts are made to increase effectiveness of sheet forming machines. The key performance indicator OEE is used to determine improvements in the elimination of perturbations during the forming process.\nProduction automation.\nIn the field of production automation, IPH focuses on artificial intelligence, distributed systems, and the use of wireless communication on production sites.\nSince the beginning of the new millennium, the IPH has been researching the use of methods of artificial intelligence in industrial engineering. The company’s main focus is on the performance-oriented and cost-effective design of interlinked assembly lines through the use of data mining.\nRecent research centers on the positioning of cooling channels in injection molding tools, the design of pre-forming geometries for forging processes, and autonomously controlled automated guided vehicles (AGV).\nDistributed systems are also subject of research at IPH. As a result of a project funded by the German Federal Ministry of Education and Research (Bundesministerium für Bildung und Forschung, BMBF), an electric tool log was developed. In another research project funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG), intelligent diamond cutting discs were designed. In this particular case, the distributed system consisted of piezoelectric sensors detecting tool vibrations, a measuring system processing and enhancing signals, and a radio module processing signals to a measuring computer.\nIPH also concentrates its research efforts on wireless communication and the use of this technology on production sites. To fight the production of counterfeit medications, a new method of integrating RFID tags and antennas into drug packages was developed as part of the EZ pharm project (www.ez-pharm.de). Lately, the Zigbee technology has been applied to an abrasive sheet during a cutoff grinding process.\nRecent research in the field of production automation focuses on optical communication. To enable automated guided vehicles to detect their position, a system based on visible light is being designed (www.isi-walk.de). Also, for the use in intralogistics, a new method of identifying goods is being developed.\nLogistics.\nWith regard to logistics, IPH engineers do research on how to design and control production networks efficiently, both ecologically and economically. For example, the project \"synchronization of logistic responsiveness in production networks\" revealed that structural interactions within networks have a strong influence on dynamic behavior and thus logistic performance.\nFurthermore, a scientific method aiming at the economic and organizational planning and assessment of transformability in supply chains is currently being developed as part of the research project “ISI-WALK” (www.isi-walk.de). The method is supposed to help companies to identify e.g. the right point of time to initiate transformation processes.\nIn various research projects, IPH employees investigate in-plant production logistics. In the special research field dealing with flashless precision forging (“Sonderforschungsbereich 489”), a new batch size calculation method has been developed. It allows for the consideration of bulk forming tool endurance, and thus helps forging companies to avoid additional costs.\nAn IPH development that has become part of business life is the logistics key performance indicator system developed in a research project called LogiBEST. The KPI system applies to procurement, production, and distribution. Based on this KPI system, the Association of German Engineers (Verein Deutscher Ingenieure, VDI) developed its guideline “VDI-Richtlinie 4400“.", "Engineering,_Manufacturing": 1.0000002384, "qwen": "Yes"}
{"id": "33811902", "revid": "143538", "url": "https://en.wikipedia.org/wiki?curid=33811902", "title": "Tool management", "text": "Tool management is needed in metalworking so that the information regarding the tools on hand can be uniformly organized and integrated. The information is stored in a database and is registered and applied using tool management. Tool data management consists of specific data fields, graphics and parameters that are essential in production, as opposed to managing general production equipment.\nUnlike hand tools, a tool in numerically (digitally) controlled machines is composed of several parts, such as the cutting tool (which may be one piece or comprise a body plus indexable inserts), a collet, and a toolholder with a machine taper. Putting the parts together accurately into an assembly is required to achieve error-free production.\nProcessing a part with a CNC (computer numerically controlled) machining operation requires several tool assemblies that are documented in a list. Each component, each assembly and each list has an identifier under which the specifications are found. Tool management is divided into documentation (master data) and logistics (transaction data). The documentation includes information needed for a trouble-free and a comprehensible production process. Spare parts, experiences in production and the corresponding data can be managed. Several functions are available to manage, process, print and combine with other applications.\nLogistics deals with demand planning, supplies and tool location. This includes, on one hand, the location in the warehouse and the purchasing of individual parts with the corresponding consumption report. It also allows for the planning and coordination of the movements of the assemblies within the shop floor.\nIn the decades of the 2000s and 2010s, tool management has increasingly moved toward a universal, industry-standard, machine-readable format for encoding tooling information, which makes possible better software, greater automation, and better simulation. ISO 13399 (Cutting tool data representation and exchange) \"is an international standard designed to give industry a common language to describe cutting tool products in a digital format.\"\nMaster data.\nMaster data describes tools' geometric characteristics, composition and usage. The information is divided into specifications and usage instructions. Master data describes the tool in its qualitative aspects, but does not provide quantities and locations.\nComponents.\nThe components are individual elements that can be combined into an assembly. Components are purchased as a unit and stored in a tool room. Cutting components (e.g. inserts) wear out during use and therefore must be purchased and replaced periodically. Non-cutting components (e.g. collets) are practically unlimited. They are often acquired together with a new machine. (Clamping equipment is handled like non-cutting components.)\nGenerally, four types of graphic illustrations are used: \nTool assemblies.\nThe tool assembly is built using several components. The component at the rear end must connect the machine tool, and the cutting component is found on the other end (ex.: drill or insert). Varying components are used intermediately (ex.: extension, collets) to reach the desired geometry. The assembly documentation describes how the components are assembled, to ensure that the applied geometry in the CAM system matches that of the real tools in the CNC machine.\nTool lists / manufacturing operation.\nThe tool list includes all tool assemblies needed for a machining operation. It is printed as a pick list and is used for commissioning and providing advice for assembly setup. Often instructions and information are not directly related to the tools (e.g. clamping, clamping fixtures, the name of the NC program, etc.) to ensure that all documents for an operation can be viewed together.\nAuxiliary tables.\nIn addition to the main tool data, auxiliary data tables simplify data acquisition, using values selected from a table. Compared to manual input, this ensures more comfortable and consistent data collection.\nTransaction data (logistics).\nLogistics is concerned with inventory, storage areas and purchasing. Within logistics, the components and the assemblies are separate. The components differentiate between internal material flow and purchasing goods from external suppliers (stock control).\nStock control of components.\nThe logistics of components includes primarily inventory management, requirements planning monitoring of minimum stock levels. When reaching the minimum level, tool management triggers a procurement process. The logistics of tool management use a workplace-tuned user interface and interfaces to storage systems and other facilities within the shop floor. The requirement for coordinated component inventory is a central tool organization in which all components of a production unit are stored at one location, and each withdrawal is recorded reliably.\nIn-house logistics of components.\nIn-house logistics is mainly interested in where a wanted component currently is, and at what cost center it is consumed. This method only consumes wear parts (cutting), the other components (holders, clamping devices) are moved between toolroom, storage places and machine tool. Component booking at the individual cost centers and locations occurs simultaneously when withdrawn/restored to the toolroom. The preparation of tools and resources is triggered by a production order. It refers to a tool list in the master data, that lists required components. Prior to usage in the machine tool, the components are assembled, according to the specifications and work instructions in the tool list. When scheduling production orders, inventory for each component will be checked.\nIn-house logistics of assemblies.\nAssemblies are built from components, and after usage usually disassembled into components and restored again. From one assembly, multiple copies can be assembled simultaneously, if the components are available in sufficient numbers. The logistics of assemblies refers to the condition and location of these copies.\nEach copy of an assembly can typically be in one of three states: \nWhen scheduling a production order, the relevant tools, for the work are known, based on the tool list. Also, known is which assemblies, required for the machining process, are already located on the machine tool. Necessary, but not yet available assemblies are calculated and printed in a net loading list. They either have to be assembled or removed from the intermediate storage. With a coordinated logistic of the assemblies, it is possible to reduce the time required for providing and replacement of assemblies at the machine.\nIntegration of tool data.\nTool management guarantees efficient and faultless order processing. Existing knowledge is made generally available and the guidelines stated in the master data are noticed. The integration of tool data enables other applications to use the tool data which is maintained with tool management. Applications either fall back on the tool management database, or the data will be replaced by the interfaces. Especially in CNC manufacturing where several persons are involved in the production process, integration avoids faults, delays and duplicate data recording.\nPDM (documentation).\nIn product data management (PDM) systems every product's work plan is saved which comprises CAD Models, the description of working steps and a list of needed equipment. The detailed description of the equipment takes place in tool management because the PDM system does not offer functions and data fields do describe them in detail. It typically offers links to external data. Production orders are generated with the ERP system which links to the work plan in the PDM system. Needed resources such as NC programs, tools, and instructions are requested in production from tool management. Integration guarantees availability of the information in tool management. The basic objective for integration is a systematic numbering of documents and resources.\nERP (purchasing).\nThe ERP system plans raw material, consumable items and other resources. It closely connects with PDM and assumes the tasks of materials management and logistics. Related to the tools, this concerns the consumable components. If the component inventory is conducted with tool management, purchase orders will be transmitted as purchase requisitions to the ERP system which issues the actual order. This requires that the products be registered in both systems with the same number. Additionally all internal stock movements of tool components for the costing can be handed to the ERP system with the integration.\nCAM.\nCAM systems generate the G-Code commands (NC program) for the CNC machine. Geometry, description and cutting conditions are selected and received directly from tool management. This ensures that all tools used are documented and consistent with the reality in the workshop. From the CAM system, all tools used in an NC program are automatically saved as tool lists in tool management. This ensures the correct use of the tools during the preparation of the work process.\nStorage systems.\nBesides conventional tool cabinets, storage systems that provide the operator with the shelf containing the desired product are often used. The relationship between the item number and the storage location is saved in tool management. When booking a tool removal in the logistics area of tool management the storage system is operated automatically. Alternatively, assignment of storage locations can be configured in the storage system. The removal is then performed on the storage system and the inventory change is transmitted to tool management.\nPresetting.\nAt the processing to the tools' positioning the CNC machine needs their exact measurements. Therefore, the length and diameter of the complete tools must be entered when connecting them to the machine. These settings of the tools can be measured with an external pre-setter. Convenient pre-setters assume the nominal values, tolerances and designation from tool management and pass the measured values directly to the CNC machine. The integration of tool management with the pre-setters takes place in the exchange format of the respective equipment manufacturers and includes graphics and information about the measurement method.\nTool catalogues.\nTo reduce the cost of initial data acquisition of the components in tool management, tool manufacturers provide the data and graphics in an appropriately conditioned form. For technical data, the DIN 4000 and the ISO 13399 exchange formats are currently used. Where required, 2D graphics are provided in accordance with the ISG / BMG DXF standard. For 3D graphics, no standard is defined. Normally, STL and STEP format are offered and axis position is chosen according to the application on the machine.\nMotivation for tool management.\nGreater ROI.\nThe bottom-line motivation for tool management, as with all manufacturing technologies, is greater return on investment through higher efficiency. This is achieved as follows:\nUtilization of new technologies.\nRising demands in design and quality, combined with time and cost pressures, force companies to regularly invest in more efficient equipment and procedures. Modern CNC-Machines (i.e. Mill-Turn-Machines) are highly productive, however they demand rigorous preparation and application. A prerequisite for their successful use is therefore the simultaneous adaptation of the organization together with the management of necessary operational information. The knowledge can subsequently be included in operational procedures and made available for each necessary task. This avoids the flawed or incomplete information that can interrupt production.\nSupplying the right information.\nNewly purchased equipment is supplied with specific usage information (i.e. cutting data with tools). This information is found in supplier specific documentation (i.e. the maximum allowed diameter of a fine boring tool). Before the new acquisition can be used, the data must be integrated in the company-specific task format. (i.e. The exact setup values for a required fine boring tool). Furthermore, this information must be made available to all participating work areas. (i.e. the exact adjusted diameter must be made known to the NC programming and tool store departments). Processed company information is then made available as part data instructions (i.e. appropriate cutting values for a particular tools usage with a specified material) and must be managed and integrated within workflows to prevent production capacity loss or shortening tool life.\nMake information more easily available.\nTool and production data is managed within a company database and in a specific format. For this purpose a software application provides accessed across all departments and used without registering duplicate data. Such data can be utilized by other software applications (i.e. CAM-Systems, tool pre-setters, shop floor logistics). Suitable interfaces are integrated to secure smooth, seamless workflows. Central data management reduces errors and production stoppages.\nValue.\nThe importance of exchanging information between operational areas varies according to the type of company. Generally it can be said that missing or unclear information is the source of errors that cost capacity and generate delays and inefficient workflow. Manual interfaces and information passed by word of mouth are potential error sources and obstacles. Especially important are binding specifications that are involved in complex work situations to reduce the chance of machine damage as well as the risks involved with defective deliveries.", "Engineering,_Manufacturing": 1.0000084639, "qwen": "Yes"}
{"id": "4608424", "revid": "1487243", "url": "https://en.wikipedia.org/wiki?curid=4608424", "title": "Factory (disambiguation)", "text": "A factory is an industrial site where goods are manufactured or processed.\nFactory or The Factory may also refer to:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "4616068", "revid": "44690822", "url": "https://en.wikipedia.org/wiki?curid=4616068", "title": "Contract packager", "text": "A contract packager, or co-packer, is a company that packages products for their clients. The packaging and labeling services can be used for many types of products including foods, pharmaceuticals, household products, and industrial products.\nFunctions of contract packaging.\nThere can be a variety of reasons for using contract packaging.\nIndustries served.\nContract packagers can serve an array of industries. Below are some of the most common industries served, and the products that may be packaged:\nRelationships.\nThe details of the relationship between the manufacturer, brand owner, and contract packager can vary. Some contract packagers perform limited operations, with all materials provided by the primary manufacturer. Product engineers are sometimes present to observe and supervise packaging operations. Other contract packaging firms are active in the package design process, provide purchasing services for materials and components, and provide shipping and logistics operations.\nA Contract manufacturer can also be a contract packager. If not a separate contract packager can be employed by the contract manufacturer.\nContract packaging equipment.\nContract packaging companies make use of a range of different machines, typically utilized on automated lines for faster production and turnaround times. Automated bottling lines may be used for containing liquids such as water, soft drinks, beer, and wine, and are capable of filling bottles at a rate of 30,000 bottles per hour. Auger filling machines can be used for packaging dry products including powders, seeds, vitamins, and other small items.\nOther complex machines exist in the contract packaging industry, such as the vertical form fill sealing machine. This machine produces plastics bags from a roll of film while simultaneously filling the bags with liquid or solid products.\nContract packagers may utilize different pieces of equipment to achieve the desired product packaging, whether the items need to be shrink wrapped, or contained in blister packs, clamshells, sealed food trays, stand-up pouches, bottles or cartons.", "Engineering,_Manufacturing": 0.9997345805, "qwen": "Yes"}
{"id": "24959666", "revid": "21417351", "url": "https://en.wikipedia.org/wiki?curid=24959666", "title": "Parts locator", "text": "A parts locator or inventory locator is a computer program that enables users to locate spare parts or other inventory items in a number of different storage locations, usually of different owners.\nA parts locator can be used to improve spare parts management by increasing parts availability and decreasing obsolescence.\nParts locators can be included in other (packaged) software such as Dealership Management Systems (DMS) or inventory control systems; or can be offered as a separate program. Due to the purpose of the software, it becomes more valuable when it has more users, as the number of inventories that are made available increases with the number of users.\nExamples of specialised suppliers of parts locators are OEConnection, PareX Parts Exchange (PareX) and Inventory Locator Service, LLC (ILS).", "Engineering,_Manufacturing": 0.9996036887, "qwen": "Yes"}
{"id": "24963265", "revid": "44662368", "url": "https://en.wikipedia.org/wiki?curid=24963265", "title": "Shear (sheet metal)", "text": "There are many types of shears used to shear or cut sheet metal.\nTypes.\nAlligator shear.\nAn alligator shear, historically known as a lever shear and sometimes as a crocodile shear, is a metal-cutting shear with a hinged jaw, powered by a flywheel or hydraulic cylinder. Alligator shears are generally set up as stand-alone shears; however, there are types for excavators. The jaw size can range from 4 to 36 in (100 to 910 mm) long. They are generally used to cut ferrous members, such as rebar, pipe, angle iron, or I-beams.\nBench shear.\nA \"bench shear\", also known as a \"lever shear\", is a bench mounted shear with a compound mechanism to increase the mechanical advantage. It is usually used for cutting rough shapes out of medium-sized pieces of sheet metal, but cannot do delicate work. For the small shear, it mostly designed for a wide field of applications. Light weight and easy efficient operation, yet very sturdy in construction. The cutting blades fitted are carefully and accurately ground to give easy, clean quick cuts, and free of burrs. These special features help the operators save a great deal of their energy. But some shearing machines can cut sheet bar and flat bar up to 10mm. It is electrically welded together to make it a sturdy stable unit capable to withstand highest stresses due to heavy duty usage. The footplates are reinforced with bracing angles so that they give firm stability to the shear. The machine is provided with section knives with sliding blades which can be adjusted by hand to make 90 cuts on angles and T-sections of different sizes as well as with openings for cutting round and square bars.\nGuillotine.\nThe machine used is called a \"squaring shear\", \"power shear\", or \"guillotine\". The machine may be foot powered, less commonly hand powered, or mechanically or hydraulically powered. It works by first clamping the material with a ram. A moving blade then comes down across a fixed blade to shear the material. For larger shears the moving blade may be set on an angle or \"rocked\" in order to shear the material progressively from one side to the other; this angle is referred to as the \"shear angle.\" Setting the blade on an angle decreases the amount of force required, but increases the stroke. A 5-degree shear angle decreases the force by about 20% . The amount of energy used is still the same. The moving blade may also be inclined 0.5 to 2.5°, called the rake angle, to keep the material from becoming wedged between the blades. However, raking the blade compromises the squareness of the edge. The machine consists of a shear table, work-holding device, upper and lower blades, and a gauging device. The shear table is the part of the machinery that the workpiece rests on whilst being shorn. The work-holding device is used to hold the workpiece in place and keep it from moving or buckling while under stress. The upper and lower blades are the piece of machinery that actually do the cutting, while the gauging device is used to ensure that the workpiece gets worked where it is supposed to be. \nThe design of press tools is an engineering compromise. A sharp edge, strength, and durability are ideal, but a sharp edge is not very strong or durable, so blades for metal work tend to be \"square-edged\" rather than \"knife-edged\". Typical workpiece materials include aluminum, brass, bronze, and mild steel because of their outstanding shearability ratings. Stainless steel is not sheared as often due to its tendency to work-harden.\nOther geometric possibilities include the squaring shear, angle shear, bow-tie shear and bar shear. All of these have many different uses and are all used regularly in certain manufacturing fields.\nPower shears.\nA power shear is electrically or pneumatically powered liderwally a hand tool designed to blank large pieces of sheet metal. They are designed to cut straight lines and relatively large radius curves. They are advantageous over a bandsaw because there is not a size limit. Large versions can cut sheet metal up to 12 gauge.\nAn alternative to the hand tools are hydraulically powered tools attached to heavy machinery. They are usually used to cut materials that are too bulky to be transported to a cutting facility, too big or dangerous for the hand tools and are stored at remote locations (e.g. mines, forests).\nThroatless shear.\nA throatless shear is a cutting tool used to make complex straight and curved cuts in sheet metal. The throatless shear takes its name from the fact that the metal can be freely moved around the cutting blade (it does not have a throat down which metal must be fed), allowing great flexibility in shapes that can be cut.\nTin snips.\nSnips, also known as shears, are hand tools used to cut sheet metal and other tough webs. It is a cutting tool. Workers use various types of snips, either straight or blend one be obtained. The straight or bent being not only for straight cuts but for inside of the curvature or concave curvature too. There are two broad categories: tinner's snips, which are similar to common scissors, and compound-action snips, which use a compound leverage handle system to increase the mechanical advantage.", "Engineering,_Manufacturing": 1.000007391, "qwen": "Yes"}
{"id": "24993427", "revid": "1135614448", "url": "https://en.wikipedia.org/wiki?curid=24993427", "title": "Gemini Group", "text": "Gemini Group, Inc. is a supplier of engineered plastic and metal products to OEM's and Tier 1 suppliers. The company operates internationally from its headquarters in Bad Axe, Michigan in the United States.\nHistory.\nGemini Group was established in 1972 by Bill Roberts and Frank Peplinski.\nInitial business offerings included sewing seatbelts and blow molding seatbelt covers for automotive Tier 1 companies in the United States and Mexico. When customers began moving operations to Mexico, the company diversified operations and a plastic extrusion division was born. \nIn 1979, the company partnered with two precision machining companies and a production machining company to form a manufacturing alliance.\nDuring the next two decades, the alliance continued to grow through the acquisition of a two-shot injection moulding company, the creation of a blow molding company, the development of an automotive interior trim manufacturing operation, and the addition of an aluminum extrusion tooling company. \nEach of the plastics and metals operations operated individually until 1996, at which time they united under one parent company, Gemini Group, Inc. \nThe company is one of the largest employers in Huron County, Michigan, where it operates four plastics plants and three metals plants. Outside of Michigan, Gemini Group operates facilities in Muscle Shoals, Alabama, El Paso, Texas, and Saltillo, Mexico.\nOne of the former owners of Gemini Group, Bill Roberts, died on May 3, 2007.\nOperations.\nThe Company is structured as follows:\nRecognition from suppliers.\nIn 2009, Johnson Controls presented Gemini Group with a Bronze 2009 Supplier Performance\nAward. In 2007, Johnson Controls gave Gemini Group a Gold Supplier Performance Award and in 2006, a Silver award.", "Engineering,_Manufacturing": 0.9995515347, "qwen": "Yes"}
{"id": "5205119", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=5205119", "title": "Supply chain optimization", "text": "Supply-chain optimization (SCO) aims to ensure the optimal operation of a manufacturing and distribution supply chain. This includes the optimal placement of inventory within the supply chain, minimizing operating costs including manufacturing costs, transportation costs, and distribution costs. Optimization often involves the application of mathematical modelling techniques using computer software. It is often considered to be part of supply chain engineering, although the latter is mainly focused on mathematical modelling approaches, whereas supply chain optimization can also be undertaken using qualitative, management based approaches.\nApplications.\nTypically, supply-chain managers aim to maximize the profitable operation of their manufacturing and distribution supply chain. This could include measures like maximizing gross margin return on inventory invested (GMROII) (balancing the cost of inventory at all points in the supply chain with availability to the customer), minimizing total operating expenses (transportation, inventory and manufacturing), or maximizing gross profit of products distributed through the supply chain. Supply-chain optimization addresses the general supply-chain problem of delivering products to customers at the lowest total cost and highest profit, trading off the costs of inventory, transportation, distributing and manufacturing. In addition, optimizing storage and transportation costs by means of product / package size is one of the easiest and most cost effective initial implementations available to save money in product distribution.\nSupply-chain optimization has applications in all industries manufacturing and/or distributing goods, including retail, industrial products, and consumer packaged goods (CPG).\nApproaches and solutions.\nThe classic supply-chain approach has been to try to forecast future inventory demand as \"accurately\" as possible, by applying statistical trending and \"best fit\" techniques based on historic demand and predicted future events. The advantage of this approach is that it can be applied to data aggregated at a fairly high level (e.g. category of merchandise, weekly, by group of customers), requiring modest database sizes and small amounts of manipulation. Unpredictability in demand is then managed by setting safety stock levels, so that for example a distributor might hold two weeks of supply of an article with steady demand but twice that amount for an article where the demand is more erratic. Universally accepted statistical methods such as Standard Deviation and Mean Absolute Deviation are often used for calculating safety stock levels.\nThen, using this forecast demand, a supply-chain manufacturing Production Planning and distribution plan is created to manufacture and distribute products to meet this forecast demand at lowest cost (or highest profitability). This plan typically addresses the following business concerns:\n- How much of each product should be manufactured each day?\n- How much of each product should be made at each manufacturing plant?\n- Which manufacturing plants should re-stock which warehouses with which products?\n- What transportation modes should be used for warehouse replenishment and customer deliveries?\nThe technical ability to record and manipulate larger databases more quickly has now enabled a new breed of supply-chain-optimization solutions to emerge, which are capable of forecasting at a much more \"granular\" level (for example, per article per customer per day). Some vendors are applying \"best fit\" models to this data, to which safety stock rules are applied, while other vendors have started to apply stochastic techniques to the optimization problem. They calculate the most desirable inventory level per article for each individual store for their retail customers, trading off cost of inventory against expectation of sale. The resulting optimized inventory level is known as a \"model stock\". Meeting the model stock level is also an area requiring optimization. Because the movement of product to meet the model stock, called the stock transfer, needs to be in economic shipping units such as complete unit loads or a full truckload, there are a series of decisions that must be made. Many existing distribution-requirements-planning systems round the quantity up to the nearest full shipping unit. For example, the creation of truckloads as economic shipment units requires optimization systems to ensure that axle constraints and space constraints are met while loading can be achieved in a damage-free way. This is generally achieved by continuing to add time-phased requirements until the loads meet some minimum weight or cube. More sophisticated optimization algorithms take into account stackability constraints, load and unloading rules, palletizing logic, warehouse efficiency and load stability with an objective to reduce transportation spend (minimize 'shipping air').\nOptimization solutions are typically part of, or linked to, the company's replenishment systems distribution requirements planning, so that orders can be automatically generated to maintain the model stock profile. The algorithms used are similar to those used in making financial investment decisions; the analogy is quite precise, as inventory can be considered to be an investment in prospective return on sales.\nSupply-chain optimization may include refinements at various stages of the product lifecycle, so that new, ongoing and obsolete items are optimized in different ways, and adaptations for different classes of products, for example seasonal merchandise. It should also factor in risks and unexpected constraints that often affect a global supply chain's efficiency, including sudden spikes in fuel costs, material shortages, natural disasters such as hurricanes, and instability of global politics.\nWhilst most software vendors are offering supply-chain optimization as a packaged solution and integrated in ERP software, some vendors are running the software on behalf of their clients as application service providers.\nClaimed advantages.\nFirstly, the techniques being applied to supply-chain optimization are claimed to be \"academically credible\". Most of the specialist companies that have been created as a result of research projects are in academic institutions or consulting firms: and they point to research articles, white papers, academic advisors and industry reviews to support their credibility.\nSecondly, the techniques are claimed to be \"commercially effective\". The companies publish case studies that show how clients have achieved significant and measurable benefits in terms of reduced inventory and lower logistics cost levels, while typically maintaining or improving customer service through better predictability and improved availability. Kokoris notes that a supply chain optimization initiative can represent \"an untapped opportunity to realize increased short and long-term cash flows and cost savings\". However, there is limited published data outside of these case studies, and a reluctance for some practitioners to publish details of their successes (which may be commercially sensitive), therefore hard evidence is difficult to come by. Last, not least, independent advisors or benchmarks show the stickiness and benefits achieved in specific sub-sectors.\nThe different routines in supply-chain optimization have reached mature status and allow companies to gain competitive advantage by increased effectiveness and measurable savings.\nDirect plant shipments.\nAlso known as direct shipment, direct plant shipment (DPS) is a method of delivering goods from the plant to the customer directly. At the same time regional centers, strategically located, provide overnight shipments to the maximum number of customers. This delivery scheme reduces transportation and storage costs.", "Engineering,_Manufacturing": 0.9999701977, "qwen": "Yes"}
{"id": "1593195", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1593195", "title": "Spin welding", "text": "Spin welding is a friction welding technique used on thermoplastic materials, in which the parts to be welded are heated by friction. The heat may be generated by turning on a lathe, a drill press, or a milling machine, where one part is driven by the chuck, and the other is held stationary with the spinning part driven against it. This is continued until the heat of friction between the parts reaches a sufficient level for the parts to weld. The stationary part is then released to spin as well, while pressure is applied along the axis of rotation, holding the parts together as they cool.\nIn the 1970s, Mattel sold a toy called \"Spinwelder\", which consisted of a high-speed motor in a handle that spun a small plastic welding rod against a plastic joint to form a bond. Mattel sold construction kits sold for the purpose of assembling with the Spinwelder.", "Engineering,_Manufacturing": 1.0000067949, "qwen": "Yes"}
{"id": "9789196", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=9789196", "title": "Focal surface", "text": "For a surface in three dimension the focal surface, surface of centers or evolute is formed by taking the centers of the curvature spheres, which are the tangential spheres whose radii are the reciprocals of one of the principal curvatures at the point of tangency. Equivalently it is the surface formed by the centers of the circles which osculate the curvature lines.\nAs the principal curvatures are the eigenvalues of the second fundamental form, there are two at each point, and these give rise to two points of the focal surface on each normal direction to the surface. Away from umbilical points, these two points of the focal surface are distinct; at umbilical points the two sheets come together. When the surface has a ridge the focal surface has a cuspidal edge, three such edges pass through an elliptical umbilic and only one through a hyperbolic umbilic. At points where the Gaussian curvature is zero, one sheet of the focal surface will have a point at infinity corresponding to the zero principal curvature.\nIf formula_1 is a point of the given surface, formula_2 the unit normal and formula_3 the principal curvatures at formula_1, then \nare the corresponding two points of the focal surface.", "Engineering,_Manufacturing": 0.9979782701, "qwen": "Yes"}
{"id": "9789742", "revid": "44274926", "url": "https://en.wikipedia.org/wiki?curid=9789742", "title": "ISO 13399", "text": "ISO 13399 (Cutting tool data representation and exchange) is an international technical standard by ISO (the International Organization for Standardization) for the computer-interpretable representation and exchange of industrial product data about cutting tools and toolholders. The objective is to provide a mechanism capable of describing product data regarding cutting tools, independent from any particular system. The nature of this description makes it suitable not only for neutral file exchange (free of proprietary format constraints), but also as a basis for implementing and sharing product databases and archiving, regarding cutting tools.\nTypically ISO 13399 can be used to exchange data between computer-aided design (CAD), computer-aided manufacturing (CAM), computer-aided engineering (CAE), tool management software, product data management (PDM/EDM), manufacturing resource planning (MRP) or enterprise resource planning (ERP), and other computer-aided technologies (CAx) and systems.\nThe usage of the ISO 13399 standard will simplify the exchange of data for cutting tools. Expected results are lower cost for managing the information about tools and a more accurate and efficient usage of manufacturing resources. The ISO 13399 has been developed with contributions from AB Sandvik Coromant, the Royal Institute of Technology in Stockholm, Kennametal Inc, and Ferroday Ltd.\nISO 13399 is developed and maintained by the ISO technical committee TC 29, Small tools, sub-committee WG34. Like other ISO and IEC standards ISO 13399 is copyright by ISO and is not freely available. Other standards developed and maintained by ISO TC29/WG34 are:\nStructure.\nISO 13399 is divided into several parts:\nISO 13399 defines a data model for cutting tool information using the EXPRESS modelling language. Application data according to this data model can be exchanged either by a STEP-File, STEP-XML or via shared database access using SDAI. \nThe dictionary (reference data library) of ISO 13399 currently uses PLIB (ISO 13584, IEC 61360).\nSee also.\nList of ISO standards 12000–13999#ISO_13000_–_ISO_13999", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "9790509", "revid": "12816229", "url": "https://en.wikipedia.org/wiki?curid=9790509", "title": "Hot air solder leveling", "text": "HASL or HAL (for hot air (solder) leveling) is a type of finish used on printed circuit boards (PCBs).\nThe PCB is typically dipped into a bath of molten solder so that all exposed copper surfaces are covered by solder. Excess solder is removed by passing the PCB between hot air knives.\nHASL can be applied with or without lead (Pb), but only lead-free HASL is RoHS compliant.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "9796127", "revid": "134766", "url": "https://en.wikipedia.org/wiki?curid=9796127", "title": "Package cushioning", "text": "Package cushioning is used to protect items during shipment. Vibration and impact shock during shipment and loading/unloading are controlled by cushioning to reduce the chance of product damage.\nCushioning is usually inside a shipping container such as a corrugated box. It is designed to absorb shock by crushing and deforming, and to dampen vibration, rather than transmitting the shock and vibration to the protected item. Depending on the specific situation, package cushioning is often between thick.\nInternal packaging materials are also used for functions other than cushioning, such as to immobilize the products in the box and lock them in place, or to fill a void.\nDesign factors.\nWhen designing packaging the choice of cushioning depends on many factors, including but not limited to:\nDesign for shock protection.\nProper performance of cushioning is dependent on its proper design and use. It is often best to use a trained packaging engineer, reputable vendor, consultant, or independent laboratory. \nAn engineer needs to know the severity of shock (drop height, etc.) to protect against. This can be based on an existing specification, published industry standards and publications, field studies, etc.\nKnowledge of the product to be packaged is critical. Field experience may indicate the types of damage previously experienced. Laboratory analysis can help quantify the fragility of the item, often reported in g's. Engineering judgment can also be an excellent starting point. Sometimes a product can be made more rugged or can be supported to make it less susceptible to breakage.\nThe amount of shock transmitted by a particular cushioning material is largely dependent on the thickness of the cushion, the drop height, and the load-bearing area of the cushion (static loading). A cushion must deform under shock for it to function. If a product is on a large load-bearing area, the cushion may not deform and will not cushion the shock. If the load-bearing area is too small, the product may “bottom out” during a shock; the shock is not cushioned. Engineers use “cushion curves” to choose the best thickness and load-bearing area for a cushioning material. Often two to three inches (50 – 75 mm) of cushioning are needed to protect fragile items.\nComputer simulations and finite element analysis are also being used. Some correlations to laboratory drop tests have been successful. \nCushion design requires care to prevent shock amplification caused by the cushioned shock pulse duration being close to the natural frequency of the cushioned item.\nDesign for vibration protection.\nThe process for vibration protection (or isolation) involves similar considerations as that for shock. Cushions can be thought of as performing like springs. Depending on cushion thickness and load-bearing area and on the forcing vibration frequency, the cushion may 1) not have any influence on input vibration, 2) amplify the input vibration at resonance, or 3) isolate the product from the vibration. Proper design is critical for cushion performance.\nEvaluation of finished package.\nVerification and validation of prototype designs are required. The design of a package and its cushioning is often an iterative process involving several designs, evaluations, redesigns, etc. Several (ASTM, ISTA, and others) published package testing protocols are available to evaluate the performance of a proposed package. Field performance should be monitored for feedback into the design process.", "Engineering,_Manufacturing": 1.000007391, "qwen": "Yes"}
{"id": "9801624", "revid": "33594889", "url": "https://en.wikipedia.org/wiki?curid=9801624", "title": "Cleco (fastener)", "text": "A cleco, also spelled generically cleko, is a temporary fastener developed by the Cleveland Pneumatic Tool Company. Widely used in the manufacture and repair of aluminum-skinned aircraft, it is used to temporarily fasten sheets of material together, or to hold parts such as stiffeners, frames etc together, before they are permanently joined. \nOperation.\nClecos are installed in holes drilled through the workpieces (usually holes intended for permanent fasteners installed later). They expand on the far side of the workpieces and then draw and clamp them together while maintaining the desired alignment and preventing distortion of the pieces. Clecos should fit snugly in their holes to prevent shifting of the workpieces and maintain the alignment of fastener holes which do not have Clecos in them. They are blind fasteners; so they can be installed in assemblies where the worker does not have access to the other side. If permanent fasteners are installed in Cleco holes, a Cleco will be removed when its hole is needed. If the workpieces are bonded or welded, then the Cleco holes may need to be filled later.\nFastener and tool.\nThe basic type consists of a steel cylinder body, a plunger on the top, a spring, a pair of step-cut locks, and a spreader bar. A special type of pliers are used to push in the spring-loaded plunger. This pushes down on the step-cut locks, which pushes them away from the spreader bars and allows them to come together. This allows the user to slip the locking jaws through a hole made through multiple sheets of material. When the plunger is released the spring pulls the locking jaws back towards the spreader bar, which separates the two jaws. The material sheets are then squeezed in between the step-cut area and the steel cylinder. This keeps the holes in the separate sheets aligned.\nDesign variations.\nCleco-type fasteners are also available with a threaded mechanism to draw the spreader bar up. Clecos of this type take more time to install and remove, but can pull parts together more tightly than the spring-type Clecos. They are commonly available with a wingnut for hand tightening, or with a simple hex nut so that they may be spaced more closely together. In either case they will usually have a hexagonal body that may be better gripped to tighten or release the spreader bar.\nSizes and color-coding.\nRegardless of their form, they are typically color-coded for ready identification of their size.", "Engineering,_Manufacturing": 0.9986395836, "qwen": "Yes"}
{"id": "2541934", "revid": "13625714", "url": "https://en.wikipedia.org/wiki?curid=2541934", "title": "Marking gauge", "text": "A marking gauge, also known as a scratch gauge, is used in woodworking and metalworking to mark out lines for cutting or other operations. The purpose of the gauge is to scribe a line parallel to a reference edge or surface. It is used in joinery and sheetmetal operations.\nThe gauge consists of a beam, a headstock, and a scribing or marking implement, typically a pin, knife, pen or wheel. The headstock slides along the beam, and is locked in place by various means: a locking screw, cam lever, or a wedge. The marking implement is fixed to one end of the beam. \nTypes.\nThe marking implement is chosen depending upon the operation to be performed. Some marking gauges have the capability to allow a number of implements to be fitted, others do not; and a woodworker will often have a number of different types. A steel pin is used when scribing with the grain. A steel knife is used when scribing across the grain. The pen or pencil is used when the woodworker does not wish the surface to be marred. Generally speaking, the pin and knife yield more accurate marking than do the pen or pencil. It is also used to mark parallel lines to the face side and edge side. \nVariations.\nThe style of gauge which uses a knife instead of a pin is often described as a \"cutting gauge\". This tool is sometimes used to slightly \"mark\" the wood before a cut to prevent tearout later when doing the main cut with for example a circular saw.\nOther variations include a \"panel gauge\" which has a longer beam and larger headstock for scribing lines that are further from the reference edge. A mortise gauge has two pins that can be adjusted relative to each other at the end of the beam. This gauge is used to scribe two lines simultaneously and is most commonly used to lay out mortise and tenon joinery.", "Engineering,_Manufacturing": 0.9981837273, "qwen": "Yes"}
{"id": "61021305", "revid": "12356153", "url": "https://en.wikipedia.org/wiki?curid=61021305", "title": "2019–20 UEFA Europa League qualifying phase and play-off round (Main Path)", "text": "This page summarises the Main Path matches of 2019–20 UEFA Europa League qualifying phase and play-off round.\nTimes are CEST , as listed by UEFA (local times, if different, are in parentheses).\nPreliminary round.\nSummary.\n\nNotes\n\nMatches.\n\"2–2 on aggregate. Progrès Niederkorn won on away goals.\"\n\"Endorgany won 3–1 on aggregate.\"\n\"Europa won 6–3 on aggregate.\"\n\"Ballymena United won 2–0 on aggregate.\"\n\"St Joseph's won 3–1 on aggregate.\"\n\"KÍ Klaksvík won 9–1 on aggregate.\"\n\"Cliftonville won 4–0 on aggregate.\"\nFirst qualifying round.\nSummary.\n\nNotes\n\nMatches.\n\"Malmö FF won 11–0 on aggregate.\"\n\"Connah's Quay Nomads won 3–2 on aggregate.\"\n\"KuPS won 3–1 on aggregate.\"\n\"Vaduz won 2–1 on aggregate.\"\n\"Shamrock Rovers won 4–3 on aggregate.\"\n\"Ordabasy won 3–0 on aggregate.\"\n\"Legia Warsaw won 3–0 on aggregate.\"\n\"CSKA Sofia won 4–0 on aggregate.\"\n\"3–3 on aggregate. Gżira United won on away goals.\"\n\"Flora won 4–2 on aggregate.\"\n\"Maccabi Haifa won 5–2 on aggregate.\"\n\"Debrecen won 4–1 on aggregate.\"\n\"Čukarički won 8–0 on aggregate.\"\n\"1–1 on aggregate. Jeunesse Esch won on away goals.\"\n\"FCSB won 4–1 on aggregate.\"\n\"Crusaders won 5–2 on aggregate.\"\n\"Brøndby won 4–3 on aggregate.\"\n\"Molde won 7–1 on aggregate.\"\n\"Rangers won 10–0 on aggregate.\"\n\"Progrès Niederkorn won 3–2 on aggregate.\"\n\"Levski Sofia won 4–0 on aggregate.\"\n\"Zrinjski Mostar won 6–0 on aggregate.\"\n\"Neftçi Baku won 9–0 on aggregate.\"\n\"Fehérvár won 5–1 on aggregate.\"\n\"Shakhtyor Soligorsk won 2–0 on aggregate.\"\n\"Olimpija Ljubljana won 4–3 on aggregate.\"\n\"Honvéd won 4–2 on aggregate.\"\n\"Alashkert won 6–1 on aggregate.\"\n\"2–2 on aggregate. Spartak Trnava won 3–2 on penalties.\"\n\"Chikhura Sachkhere won 4–2 on aggregate.\"\n\"Dinamo Tbilisi won 7–0 on aggregate.\"\n\"Kairat won 4–2 on aggregate.\"\n\"3–3 on aggregate. DAC Dunajská Streda won on away goals.\"\n\"Apollon Limassol won 6–0 on aggregate.\"\n\"Ventspils won 3–1 on aggregate.\"\n\"4–4 on aggregate. Stjarnan won on away goals.\"\n\"Haugesund won 6–1 on aggregate.\"\n\"1–1 on aggregate. KÍ Klaksvík won on away goals.\"\n\"Liepāja won 3–2 on aggregate.\"\n\"IFK Norrköping won 4–1 on aggregate.\"\n\"Aberdeen won 4–2 on aggregate.\"\n\"Domžale won 5–3 on aggregate.\"\n\"Hapoel Be'er Sheva won 2–1 on aggregate.\"\n\"Budućnost Podgorica won 6–1 on aggregate.\"\n\"Universitatea Craiova won 6–4 on aggregate.\"\n\"Pyunik won 5–4 on aggregate.\"\n\"AEK Larnaca won 2–0 on aggregate.\"\nSecond qualifying round.\nSummary.\n\n\nNotes\n\nMatches.\n\"IFK Norrköping won 3–0 on aggregate.\"\n\"Hapoel Be'er Sheva won 3–1 on aggregate.\"\n\"Neftçi Baku won 4–0 on aggregate.\"\n\"Espanyol won 7–1 on aggregate.\"\n\"Atromitos won 5–3 on aggregate.\"\n\"Haugesund won 3–2 on aggregate.\"\n\"AEK Larnaca won 7–0 on aggregate.\"\n\"Legia Warsaw won 1–0 on aggregate.\"\n\"Zrinjski Mostar won 3–2 on aggregate.\"\n\"Pyunik won 2–1 on aggregate.\"\n\"Brøndby won 5–3 on aggregate.\"\n\"Vaduz won 2–1 on aggregate.\"\n\"Dinamo Tbilisi won 5–0 on aggregate.\"\n\"Yeni Malatyaspor 3–2 on aggregate.\"\n\"Eintracht Frankfurt won 4–2 on aggregate.\"\n\"Malmö FF won 5–4 on aggregate.\"\n\"Molde won 3–1 on aggregate.\"\n\"Aberdeen won 6–1 on aggregate.\"\n\"Gent won 7–5 on aggregate.\"\n\"Zorya Luhansk won 4–1 on aggregate.\"\n\"1–1 on aggregate. CSKA Sofia won 4–3 on penalties.\n\"Torino won 7–1 on aggregate.\"\n\"Luzern won 2–0 on aggregate.\"\n\"Rangers won 2–0 on aggregate.\"\n\"Ventspils won 6–2 on aggregate.\"\n\"Strasbourg won 4–3 on aggregate.\"\n\"Mladá Boleslav won 4–3 on aggregate.\"\n\"Apollon Limassol won 4–3 on aggregate.\"\n\"AZ won 3–0 on aggregate.\"\n\"FCSB won 5–3 on aggregate.\"\n\"3–3 on aggregate. Lokomotiv Plovdiv won on away goals.\"\n\"Wolverhampton Wanderers won 6–1 on aggregate.\"\n\"Aris won 1–0 on aggregate.\"\n\"Vitória de Guimarães won 5–0 on aggregate.\"\n\"0–0 on aggregate. Universitatea Craiova won 3–1 on penalties.\"\n\"Shakhtyor Soligorsk won 2–0 on aggregate.\"\n\"Partizan won 4–0 on aggregate.\"\nThird qualifying round.\nSummary.\n\n\nMatches.\n\"Hapoel Be'er Sheva won 4–2 on aggregate.\"\n\"Torino won 6–1 on aggregate.\"\n\"2–2 on aggregate. Antwerp won on away goals.\"\n\"Apollon Limassol won 5–2 on aggregate.\"\n\"Feyenoord won 5–1 on aggregate.\"\n\"Braga won 7–3 on aggregate.\"\n\"Molde won 4–3 on aggregate.\"\n\"Strasbourg won 2–0 on aggregate.\"\n\"Spartak Moscow won 5–3 on aggregate.\"\n\"FCSB won 1–0 on aggregate.\"\n\"Wolverhampton Wanderers won 8–0 on aggregate.\"\n\"Rangers won 7–3 on aggregate.\"\n\"AZ won 4–0 on aggregate.\"\n\"Gent won 4–1 on aggregate.\"\n\"Legia Warsaw won 2–0 on aggregate.\"\n\"PSV Eindhoven won 1–0 on aggregate.\"\n\"Rijeka won 4–0 on aggregate.\"\n\"Vitória de Guimarães won 9–0 on aggregate.\"\n\"Eintracht Frankfurt won 6–0 on aggregate.\"\n\"Partizan won 3–2 on aggregate.\"\n\"Malmö FF won 3–1 on aggregate.\"\n\"Zorya Luhansk won 2–1 on aggregate.\"\n\"Bnei Yehuda won 4–3 on aggregate.\"\n\"Espanyol won 6–0 on aggregate.\"\n\"Trabzonspor won 4–3 on aggregate.\"\n\"AEK Athens won 3–1 on aggregate.\"\nPlay-off round.\nSummary.\n\n\nMatches.\n\"Wolverhampton Wanderers won 5–3 on aggregate.\"\n\"Rangers won 1–0 on aggregate.\"\n\"Vitória de Guimarães won 1–0 on aggregate.\"\n\"PSV Eindhoven won 7–0 on aggregate.\"\n\"3–3 on aggregate. Trabzonspor won on away goals.\"\n\"Feyenoord won 6–0 on aggregate.\"\n\"Gent won 3–2 on aggregate.\"\n\"Espanyol won 5–3 on aggregate.\"\n\"Partizan won 3–2 on aggregate.\"\n\"Braga won 3–1 on aggregate.\"\n\"Malmö FF won 4–0 on aggregate.\"\n\"Eintracht Frankfurt won 3–1 on aggregate.\"\n\"AZ won 5–2 on aggregate.\"", "Engineering,_Manufacturing": 0.9998978376, "qwen": "Yes"}
{"id": "43282531", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=43282531", "title": "Industrial and production engineering", "text": "Industrial and production engineering (IPE) is an interdisciplinary engineering discipline that includes manufacturing technology, engineering sciences, management science, and optimization of complex processes, systems, or organizations. It is concerned with the understanding and application of engineering procedures in manufacturing processes and production methods. Industrial engineering dates back all the way to the industrial revolution, initiated in 1700s by Sir Adam Smith, Henry Ford, Eli Whitney, Frank Gilbreth and Lilian Gilbreth, Henry Gantt, F.W. Taylor, etc. After the 1970s, industrial and production engineering developed worldwide and started to widely use automation and robotics. Industrial and production engineering includes three areas: Mechanical engineering (where the production engineering comes from), industrial engineering, and management science. \nThe objective is to improve efficiency, drive up effectiveness of manufacturing, quality control, and to reduce cost while making their products more attractive and marketable. Industrial engineering is concerned with the development, improvement, and implementation of integrated systems of people, money, knowledge, information, equipment, energy, materials, as well as analysis and synthesis. The principles of IPE include mathematical, physical and social sciences and methods of engineering design to specify, predict, and evaluate the results to be obtained from the systems or processes currently in place or being developed. The target of production engineering is to complete the production process in the smoothest, most-judicious and most-economic way. Production engineering also overlaps substantially with manufacturing engineering and industrial engineering. The concept of production engineering is interchangeable with manufacturing engineering.\nAs for education, undergraduates normally start off by taking courses such as physics, mathematics (calculus, linear analysis, differential equations), computer science, and chemistry. Undergraduates will take more major specific courses like production and inventory scheduling, process management, CAD/CAM manufacturing, ergonomics, etc., towards the later years of their undergraduate careers. In some parts of the world, universities will offer Bachelor's in Industrial and Production Engineering. However, most universities in the U.S. will offer them separately. Various career paths that may follow for industrial and production engineers include: Plant Engineers, Manufacturing Engineers, Quality Engineers, Process Engineers and industrial managers, project management, manufacturing, production and distribution, From the various career paths people can take as an industrial and production engineer, most average a starting salary of at least $50,000.\nHistory.\nIndustrial Revolution.\nThe roots of the Industrial Engineering Profession date back to the Industrial Revolution. The technologies that helped mechanize traditional manual operations in the textile industry including the Flying shuttle, the Spinning jenny, and perhaps most importantly the Steam engine generated Economies of scale that made Mass production in centralized locations attractive for the first time. The concept of the production system had its genesis in the factories created by these innovations.\nSpecialization of labor.\nAdam Smith's concepts of Division of Labour and the \"Invisible Hand\" of capitalism introduced in his treatise \"The Wealth of Nations\" motivated many of the technological innovators of the Industrial revolution to establish and implement factory systems. The efforts of James Watt and Matthew Boulton led to the first integrated machine manufacturing facility in the world, including the implementation of concepts such as cost control systems to reduce waste and increase productivity and the institution of skills training for craftsmen.\nCharles Babbage became associated with Industrial engineering because of the concepts he introduced in his book \"On the Economy of Machinery and Manufacturers\" which he wrote as a result of his visits to factories in England and the United States in the early 1800s. The book includes subjects such as the time required to perform a specific task, the effects of subdividing tasks into smaller and less detailed elements, and the advantages to be gained from repetitive tasks.\nInterchangeable parts.\nEli Whitney and Simeon North proved the feasibility of the notion of Interchangeable parts in the manufacture of muskets and pistols for the US Government. Under this system, individual parts were mass-produced to tolerances to enable their use in any finished product. The result was a significant reduction in the need for skill from specialized workers, which eventually led to the industrial environment to be studied later.\nModern development.\nIndustrial engineering.\nIn 1960 to 1975, with the development of decision support systems in supply such as the Material requirements planning (MRP), people can emphasize the timing issue (inventory, production, compounding, transportation, etc.) of industrial organization. Israeli scientist Dr. Jacob Rubinovitz installed the CMMS program developed in IAI and Control-Data (Israel) in 1976 in South Africa and worldwide.\nIn the seventies, with the penetration of Japanese management theories such as Kaizen and Kanban, Japan realized very high levels of quality and productivity. These theories improved issues of quality, delivery time, and flexibility. Companies in the west realized the great impact of Kaizen and started implementing their own Continuous improvement programs.\nIn the nineties, following the global industry globalization process, the emphasis was on supply chain management, and customer-oriented business process design. Theory of constraints developed by an Israeli scientist Eliyahu M. Goldratt (1985) is also a significant milestone in the field.\nManufacturing (production) engineering.\nModern manufacturing engineering studies include all intermediate processes required for the production and integration of a product's components.Some industries, such as semiconductor and steel manufacturers use the term \"fabrication\" for these processes.\nAutomation is used in different processes of manufacturing such as machining and welding. Automated manufacturing refers to the application of automation to produce goods in a factory. The main advantages of automated manufacturing for the manufacturing process are realized with effective implementation of automation and include: higher consistency and quality, reduction of lead times, simplification of production, reduced handling, improved work flow, and improved worker morale.\nRobotics is the application of mechatronics and automation to create robots, which are often used in manufacturing to perform tasks that are dangerous, unpleasant, or repetitive. These robots may be of any shape and size, but all are preprogrammed and interact physically with the world. To create a robot, an engineer typically employs kinematics (to determine the robot's range of motion) and mechanics (to determine the stresses within the robot). Robots are used extensively in manufacturing engineering.\nRobots allow businesses to save money on labor, perform tasks that are either too dangerous or too precise for humans to perform economically, and to ensure better quality. Many companies employ assembly lines of robots, and some factories are so robotized that they can run by themselves. Outside the factory, robots have been employed in bomb disposal, space exploration, and many other fields. Robots are also sold for various residential applications.\nOverview.\nIndustrial engineering.\nIndustrial engineering is the branch of engineering that involves figuring out how to make or do things better. Industrial engineers are concerned with reducing production costs, increasing efficiency, improving the quality of products and services, ensuring worker health and safety, protecting the environment and complying with government regulations.\nThe various fields and topics that industrial engineers are involved with include:\nExamples of where industrial engineering might be used include flow process charting, process mapping, designing an assembly workstation, strategizing for various operational logistics, consulting as an efficiency expert, developing a new financial algorithm or loan system for a bank, streamlining operation and emergency room location or usage in a hospital, planning complex distribution schemes for materials or products (referred to as supply-chain management), and shortening lines (or queues) at a bank, hospital, or a theme park.\nModern industrial engineers typically use predetermined motion time system, computer simulation (especially discrete event simulation), along with extensive mathematical tools for modeling, such as mathematical optimization and queueing theory, and computational methods for system analysis, evaluation, and optimization. Industrial engineers also use the tools of data science and machine learning in their work owing to the strong relatedness of these disciplines with the field and the similar technical background required of industrial engineers (including a strong foundation in probability theory, linear algebra, and statistics, as well as having coding skills).\nManufacturing (production) engineering.\nManufacturing Engineering is based on core industrial engineering and mechanical engineering skills, adding important elements from mechatronics, commerce, economics and business management. This field also deals with the integration of different facilities and systems for producing quality products (with optimal expenditure) by applying the principles of physics and the results of manufacturing systems studies, such as the following:\nManufacturing engineers develop and create physical artifacts, production processes, and technology. It is a very broad area which includes the design and development of products. Manufacturing engineering is considered to be a sub-discipline of industrial engineering/systems engineering and has very strong overlaps with mechanical engineering. Manufacturing engineers' success or failure directly impacts the advancement of technology and the spread of innovation. This field of manufacturing engineering emerged from tool and die discipline in the early 20th century. It expanded greatly from the 1960s when industrialized countries introduced factories with:\n1. Numerical control machine tools and automated systems of production.\n2. Advanced statistical methods of quality control: These factories were pioneered by the American electrical engineer William Edwards Deming, who was initially ignored by his home country. The same methods of quality control later turned Japanese factories into world leaders in cost-effectiveness and production quality.\n3. Industrial robots on the factory floor, introduced in the late 1970s: These computer-controlled welding arms and grippers could perform simple tasks such as attaching a car door quickly and flawlessly 24 hours a day. This cut costs and improved production speed.\nEducation.\nIndustrial engineering.\nUndergraduate curriculum.\nIn the United States the undergraduate degree earned is the Bachelor of Science (B.S.) or Bachelor of Science and Engineering (B.S.E.) in Industrial Engineering (IE). Variations of the title include Industrial & Operations Engineering (IOE), and Industrial & Systems Engineering (ISE). The typical curriculum includes a broad math and science foundation spanning chemistry, physics, mechanics (i.e., statics, kinematics, and dynamics), materials science, computer science, electronics/circuits, engineering design, and the standard range of engineering mathematics (i.e. calculus, linear algebra, differential equations, statistics). For any engineering undergraduate program to be accredited, regardless of concentration, it must cover a largely similar span of such foundational work – which also overlaps heavily with the content tested on one or more engineering licensure exams in most jurisdictions.\nThe coursework specific to IE entails specialized courses in aeas such as optimization, applied probability, stochastic modeling, design of experiments, statistical process control, simulation, manufacturing engineering, ergonomics/safety engineering, and engineering economics. Industrial engineering elective courses typically cover more specialized topics in areas such as manufacturing, supply chains and logistics, analytics and machine learning, production systems, human factors and industrial design, and service systems.\nCertain business schools may offer programs with some overlapping relevance to IE, but the engineering programs are distinguished by a much more intensely quantitative focus, required engineering science electives, and the core math and science courses required of all engineering programs.\nGraduate curriculum.\nThe usual graduate degree earned is the Master of Science (MS) or Master of Science and Engineering (MSE) in Industrial Engineering or various alternative related concentration titles. Typical MS curricula may cover:\nManufacturing (production) engineering.\nDegree certification programs.\nManufacturing engineers possess an associate's or bachelor's degree in engineering with a major in manufacturing engineering. The length of study for such a degree is usually two to five years followed by five more years of professional practice to qualify as a professional engineer. Working as a manufacturing engineering technologist involves a more applications-oriented qualification path.\nAcademic degrees for manufacturing engineers are usually the Associate or Bachelor of Engineering, [BE] or [BEng], and the Associate or Bachelor of Science, [BS] or [BSc]. For manufacturing technologists the required degrees are Associate or Bachelor of Technology [B.TECH] or Associate or Bachelor of Applied Science [BASc] in Manufacturing, depending upon the university. Master's degrees in engineering manufacturing include Master of Engineering [ME] or [MEng] in Manufacturing, Master of Science [M.Sc] in Manufacturing Management, Master of Science [M.Sc] in Industrial and Production Management, and Master of Science [M.Sc] as well as Master of Engineering [ME] in Design, which is a subdiscipline of manufacturing. Doctoral [PhD] or [DEng] level courses in manufacturing are also available depending on the university.\nThe undergraduate degree curriculum generally includes courses in physics, mathematics, computer science, project management, and specific topics in mechanical and manufacturing engineering. Initially such topics cover most, if not all, of the subdisciplines of manufacturing engineering. Students then choose to specialize in one or more sub disciplines towards the end of their degree work.\nSpecific to Industrial Engineers, people will see courses covering ergonomics, scheduling, inventory management, forecasting, product development, and in general courses that focus on optimization. Most colleges breakdown the large sections of industrial engineering into Healthcare, Ergonomics, Product Development, or Consulting sectors. This allows for the student to get a good grasp on each of the varying sub-sectors so they know what area they are most interested about pursuing a career in.\nUndergraduate curriculum.\nThe Foundational Curriculum for a bachelor's degree of Manufacturing Engineering or Production Engineering includes below mentioned Syllabus. This Syllabus is closely related to Industrial Engineering and Mechanical Engineering. But it Differs by Placing more Emphasis on Manufacturing Science or Production Science. It includes following:\nA degree in Manufacturing Engineering versus Mechanical Engineering will typically differ only by a few specialized classes. Mechanical Engineering degree focuses more on the Product Design Process and on Complex Products which requires more Mathematics Expertise.\nManufacturing engineering certification.\nProfessional engineering license.\nA Professional Engineer, PE, is a licensed engineer who is permitted to offer professional services to the public. Professional Engineers may prepare, sign, seal, and submit engineering plans to the public. Before a candidate can become a professional engineer, they will need to receive a bachelor's degree from an ABET recognized university in the US, take and pass the Fundamentals of Engineering exam to become an \"engineer-in-training\", and work four years under the supervision of a professional engineer. After those tasks are complete the candidate will be able to take the PE exam. Upon receiving a passing score on the test, the candidate will receive their PE License .\nSociety of Manufacturing Engineers (SME) certifications (USA).\nThe SME (society) administers qualifications specifically for the manufacturing industry. These are not degree level qualifications and are not recognized at the professional engineering level. The SME offers two certifications for Manufacturing engineers: Certified Manufacturing Technologist Certificate (CMfgT) and Certified Manufacturing Engineer (CMfgE).\nCertified manufacturing technologist.\nQualified candidates for the Certified Manufacturing Technologist Certificate (CMfgT) must pass a three-hour, 130-question multiple-choice exam. The exam covers math, manufacturing processes, manufacturing management, automation, and related subjects. A score of 60% or higher must be achieved to pass the exam. Additionally, a candidate must have at least four years of combined education and manufacturing-related work experience. The CMfgT certification must be renewed every three years in order to stay certified.\nCertified manufacturing engineer.\nCertified Manufacturing Engineer (CMfgE) is an engineering qualification administered by the Society of Manufacturing Engineers, Dearborn, Michigan, USA. Candidates qualifying for a Certified Manufacturing Engineer credential must pass a four-hour, 180 question multiple-choice exam which covers more in-depth topics than does the CMfgT exam. A score of 60% or higher must be achieved to pass the exam. CMfgE candidates must also have eight years of combined education and manufacturing-related work experience, with a minimum of four years of work experience. The CMfgT certification must be renewed every three years in order to stay certified.\nResearch.\nIndustrial engineering.\nHuman factors.\nThe human factors area specializes in exploring how systems fit the people who must operate them, determining the roles of people with the systems, and selecting those people who can best fit particular roles within these systems. Students who focus on Human Factors will be able to work with a multidisciplinary team of faculty with strengths in understanding cognitive behavior as it relates to automation, air and ground transportation, medical studies, and space exploration.\nProduction systems.\nThe production systems area develops new solutions in areas such as engineering design, supply chain management (e.g. supply chain system design, error recovery, large scale systems), manufacturing (e.g. system design, planning and scheduling), and medicine (e.g. disease diagnosis, discovery of medical knowledge). Students who focus on production systems will be able to work on topics related to computational intelligence theories for applications in industry, healthcare, and service organizations.\nReliability systems.\nThe objective of the reliability systems area is to provide students with advanced data analysis and decision making techniques that will improve quality and reliability of complex systems. Students who focus on system reliability and uncertainty will be able to work on areas related to contemporary reliability systems including integration of quality and reliability, simultaneous life cycle design for manufacturing systems, decision theory in quality and reliability engineering, condition-based maintenance and degradation modeling, discrete event simulation and decision analysis.\nWind power management.\nThe Wind Power Management Program aims at meeting the emerging needs for graduating professionals involved in design, operations, and management of wind farms deployed in massive numbers all over the country. The graduates will be able to fully understand the system and management issues of wind farms and their interactions with alternative and conventional power generation systems.\nProduction (manufacturing) engineering.\nFlexible manufacturing systems.\nA flexible manufacturing system (FMS) is a manufacturing system in which there is some amount of flexibility that allows the system to react to changes, whether predicted or unpredicted. This flexibility is generally considered to fall into two categories, both of which have numerous subcategories. The first category, machine flexibility, covers the system's ability to be changed to produce new product types and the ability to change the order of operations executed on a part. The second category, called routing flexibility, consists of the ability to use multiple machines to perform the same operation on a part, as well as the system's ability to absorb large-scale changes, such as in volume, capacity, or capability.\nMost FMS systems comprise three main systems. The work machines, which are often automated CNC machines, are connected by a material handling system to optimize parts flow, and to a central control computer, which controls material movements and machine flow. The main advantages of an FMS is its high flexibility in managing manufacturing resources like time and effort in order to manufacture a new product. The best application of an FMS is found in the production of small sets of products from a mass production.\nComputer integrated manufacturing.\nComputer-integrated manufacturing (CIM) in engineering is a method of manufacturing in which the entire production process is controlled by computer. Traditionally separated process methods are joined through a computer by CIM. This integration allows the processes to exchange information and to initiate actions. Through this integration, manufacturing can be faster and less error-prone, although the main advantage is the ability to create automated manufacturing processes. Typically CIM relies on closed-loop control processes based on real-time input from sensors. It is also known as flexible design and manufacturing.\nFriction stir welding.\nFriction stir welding was discovered in 1991 by The Welding Institute (TWI). This innovative steady state (non-fusion) welding technique joins previously un-weldable materials, including several aluminum alloys. It may play an important role in the future construction of airplanes, potentially replacing rivets. Current uses of this technology to date include: welding the seams of the aluminum main space shuttle external tank, the Orion Crew Vehicle test article, Boeing Delta II and Delta IV Expendable Launch Vehicles and the SpaceX Falcon 1 rocket; armor plating for amphibious assault ships; and welding the wings and fuselage panels of the new Eclipse 500 aircraft from Eclipse Aviation, among an increasingly growing range of uses.\nEmployment.\nIndustrial engineering.\nThe total number of engineers employed in the US in 2015 was roughly 1.6 million. Of these, 272,470 were industrial engineers (16.92%), the third most popular engineering specialty. The median salaries by experience level are $62,000 with 0–5 years experience, $75,000 with 5–10 years experience, and $81,000 with 10–20 years experience. The average starting salaries were $55,067 with a bachelor's degree, $77,364 with a master's degree, and $100,759 with a doctorate degree. This places industrial engineering at 7th of 15 among engineering bachelor's degrees, 3rd of 10 among master's degrees, and 2nd of 7 among doctorate degrees in average annual salary. The median annual income of industrial engineers in the U.S. workforce is $83,470.\nProduction (manufacturing) engineering.\nManufacturing engineering is just one facet of the engineering industry. Manufacturing engineers enjoy improving the production process from start to finish. They have the ability to keep the whole production process in mind as they focus on a particular portion of the process. Successful students in manufacturing engineering degree programs are inspired by the notion of starting with a natural resource, such as a block of wood, and ending with a usable, valuable product, such as a desk, produced efficiently and economically.\nManufacturing engineers are closely connected with engineering and industrial design efforts. Examples of major companies that employ manufacturing engineers in the United States include General Motors Corporation, Ford Motor Company, Chrysler, Boeing, Gates Corporation and Pfizer. Examples in Europe include Airbus, Daimler, BMW, Fiat, Navistar International, and Michelin Tyre.\nRelated industries.\nIndustries where industrial and production engineers are generally employed include:\nModern tools.\nMany manufacturing companies, especially those in industrialized nations, have begun to incorporate computer-aided engineering (CAE) programs, such as SolidWorks and AutoCAD, into their existing design and analysis processes, including 2D and 3D solid modeling computer-aided design (CAD). This method has many benefits, including easier and more exhaustive visualization of products, the ability to create virtual assemblies of parts, and ease of use in designing mating interfaces and tolerances.\nSolidWorks.\nSolidWorks is an example of a CAD modeling computer program developed by Dassault Systèmes. SolidWorks is an industry standard for drafting designs and specifications for physical objects and has been used by more than 165,000 companies as of 2013.\nAutoCAD.\nAutoCAD is an example of a CAD modeling computer program developed by Autodesk. AutoCad is also widely used for CAD modeling and CAE.\nOther CAE programs commonly used by product manufacturers include product life cycle management (PLM) tools and analysis tools used to perform complex simulations. Analysis tools may be used to predict product response to expected loads, including fatigue life and manufacturability. These tools include finite element analysis (FEA), computational fluid dynamics (CFD), and computer-aided manufacturing (CAM). Using CAE programs, a mechanical design team can quickly and cheaply iterate the design process to develop a product that better meets cost, performance, and other constraints. There is no need to create a physical prototype until the design nears completion, allowing hundreds or thousands of designs to be evaluated, instead of relatively few. In addition, CAE analysis programs can model complicated physical phenomena which cannot be solved by hand, such as viscoelasticity, complex contact between mating parts, or non-Newtonian flows.\nJust as manufacturing engineering is linked with other disciplines, such as mechatronics, multidisciplinary design optimization (MDO) is also being used with other CAE programs to automate and improve the iterative design process. MDO tools wrap around existing CAE processes by automating the process of trial and error method used by classical engineers. MDO uses a computer based algorithm that will iteratively seek better alternatives from an initial guess within given constants. MDO uses this procedure to determine the best design outcome and lists various options as well.\nSub-disciplines.\nMechanics.\nClassical Mechanics, attempts to use Newtons basic laws of motion to describe how a body will react when that body undergoes a force. However modern mechanics includes the rather recent quantum theory. Sub disciplines of mechanics include:\nClassical Mechanics:\nQuantum:\nIf the engineering project were to design a vehicle, statics might be employed to design the frame of the vehicle in order to evaluate where the stresses will be most intense. Dynamics might be used when designing the car's engine to evaluate the forces in the pistons and cams as the engine cycles. Mechanics of materials might be used to choose appropriate materials for the manufacture of the frame and engine. Fluid mechanics might be used to design a ventilation system for the vehicle or to design the intake system for the engine.\nDrafting.\nDrafting or technical drawing is the means by which manufacturers create instructions for manufacturing parts. A technical drawing can be a computer model or hand-drawn schematic showing all the dimensions necessary to manufacture a part, as well as assembly notes, a list of required materials, and other pertinent information. A skilled worker who creates technical drawings may be referred to as a drafter or draftsman. Drafting has historically been a two-dimensional process, but computer-aided design (CAD) programs now allow the designer to create in three dimensions. Instructions for manufacturing a part must be fed to the necessary machinery, either manually, through programmed instructions, or through the use of a computer-aided manufacturing (CAM) or combined CAD/CAM program. Programs such as SolidWorks and AutoCAD are examples of programs used to draft new parts and products under development.\nOptionally, an engineer may also manually manufacture a part using the technical drawings, but this is becoming an increasing rarity with the advent of computer numerically controlled (CNC) manufacturing. Engineers primarily manufacture parts manually in the areas of applied spray coatings, finishes, and other processes that cannot economically or practically be done by a machine.\nDrafting is used in nearly every sub discipline of mechanical and manufacturing engineering, and by many other branches of engineering and architecture. Three-dimensional models created using CAD software are also commonly used in finite element analysis (FEA) and computational fluid dynamics (CFD).\nMetal fabrication and machine tools.\nMetal fabrication is the building of metal structures by cutting, bending, and assembling processes. Technologies such as electron beam melting, laser engineered net shape, and direct metal laser sintering has allowed for the production of metal structures to become much less difficult when compared to other conventional metal fabrication methods. These help to alleviate various issues when the idealized CAD structures do not align with the actual fabricated structure.\nMachine tools employ many types of tools that do the cutting or shaping of materials. Machine tools usually include many components consisting of motors, levers, arms, pulleys, and other basic simple systems to create a complex system that can build various things. All of these components must work correctly in order to stay on schedule and remain on task. Machine tools aim to efficiently and effectively produce good parts at a quick pace with a small amount of error.\nComputer integrated manufacturing.\nComputer-integrated manufacturing (CIM) is the manufacturing approach of using computers to control the entire production process. Computer-integrated manufacturing is used in automotive, aviation, space, and ship building industries. Computer-integrated manufacturing allows for data, through various sensing mechanisms to be observed during manufacturing. This type of manufacturing has computers controlling and observing every part of the process. This gives CIM a unique advantage over other manufacturing processes.\nMechatronics.\nMechatronics is an engineering discipline that deals with the convergence of electrical, mechanical and manufacturing systems. Examples include automated manufacturing systems, heating, ventilation and air-conditioning systems, and various aircraft and automobile subsystems. A mechatronic system typically includes a mechanical skeleton, motors, controllers, sensors, actuators, and digital hardware. Mechatronics is greatly used in various applications of industrial processes and in automation.\nThe term mechatronics is typically used to refer to macroscopic systems, but futurists have predicted the emergence of very small electromechanical devices. Already such small devices, known as Microelectromechanical systems (MEMS), are used in automobiles to initiate the deployment of airbags, in digital projectors to create sharper images, and in inkjet printers to create nozzles for high-definition printing. In future it is hoped that such devices will be used in tiny implantable medical devices and to improve optical communication.\nTextile engineering.\nTextile engineering courses deal with the application of scientific and engineering principles to the design and control of all aspects of fiber, textile, and apparel processes, products, and machinery. These include natural and man-made materials, interaction of materials with machines, safety and health, energy conservation, and waste and pollution control. Additionally, students are given experience in plant design and layout, machine and wet process design and improvement, and designing and creating textile products. Throughout the textile engineering curriculum, students take classes from other engineering and disciplines including: mechanical, chemical, materials and industrial engineering.\nAdvanced composite materials.\nAdvanced composite materials (engineering) (ACMs) are also known as advanced polymer matrix composites. These are generally characterized or determined by unusually high strength fibres with unusually high stiffness, or modulus of elasticity characteristics, compared to other materials, while bound together by weaker matrices. Advanced composite materials have broad, proven applications, in the aircraft, aerospace, and sports equipment sectors. Even more specifically ACMs are very attractive for aircraft and aerospace structural parts. Manufacturing ACMs is a multibillion-dollar industry worldwide. Composite products range from skateboards to components of the space shuttle. The industry can be generally divided into two basic segments, industrial composites and advanced composites.\nSee also.\nAssociations", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "40813783", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=40813783", "title": "IPK Acrylic-polyvinyl chloride", "text": "IPK Acrylic-polyvinyl chloride (IPK, IPK Acrylic PVC, IPK Thermoformable Sheet, IPK Kydex) is a line of thermoplastic acrylic-polyvinyl chloride composite material. It has a chemical structure similar to Kydex with an Acrylic-polyvinyl chloride substrate and white cap for screen printing onto the material.\nKydex sheet was originally produced in 1965 by Rohm and Haas, having been designed for use in aircraft interiors. In recent years, Kydex has gained a hobbyist following for a wide variety of applications, including firearm holsters and sheaths for knives.\nIPK Acrylic-polyvinyl chloride was developed by Interstate Plastics in 2012 and sold under the registered trademark IPK. Interstate Plastics claims the material offers an alternative to thermoformable plastic sheets while providing a printable surface for custom designs and patterns. Most vinyl sign print shops are able to print custom designs or patterns onto the material. IPK is currently the only thermoforming sheet on the market sold with a printable cap.\nCharacteristics.\nIPK is an acrylic-polyvinyl chloride composite engineered for thermoforming applications, combining properties of both acrylic and polyvinyl chloride plastics. Acrylic adds rigidity and formability, while polyvinyl chloride, more commonly known as PVC, adds toughness and chemical resistance. Standard sheet thickness is .080 and IPK Acrylic-polyvinyl chloride can be thermoformed, post formed, brake formed and laminated.\nApplications.\nApplications range from gun holsters, knife sheaths, and medical equipment housings to aircraft trays, tables, and fixtures. IPK is very easy to clean: tough stains, scuffs, and graffiti can be removed with no staining or surface damage to the material. IPK is commonly used for thermoforming custom sized knife sheaths, gun holsters, and cell phone/tablet covers.\nCommon Application.\nIPK is primarily used by hobbyists in thermoforming firearm holsters and sheaths for knives. The printable surface allows for custom printed patterns, allowing added customization for gun and knife enthusiasts.\nLeather Substitute.\nIn many applications, especially in holster and sheath applications, IPK is used as replacement for leather. The texture of IPK is more rigid than leather, and similar in touch. IPK thermoformable sheet in comparable to leather with the following properties:\nOther Applications.\nIPK can be used as a substitute in place of Kydex in the following applications:", "Engineering,_Manufacturing": 0.9997621179, "qwen": "Yes"}
{"id": "61907040", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=61907040", "title": "U-JIN Tech Corp.", "text": "U-JIN Tech Corp. is a South Korean manufacturer of friction welding machines and automated manufacturing cells.\nHistory.\nU-JIN Tech Corp. was founded in February 2009. It stablished its own R&D center within the Korea Industrial Technology Association  in 2010. The R&D center has the objective to develop new products.\nU-Jin has initially developed and manufactured hydraulic friction welding machines, and it built Korea's first CNC friction welding machine in 2012.\nIn 2015 the company was recognized as \"Contributor for Development of Excellent Capital Goods\" by the Minister of Trade, Industry, and Energy. In November 2016 it received the European CE Certificate and started exporting machines to Europe. On Trade Day in December 2016, it received the \"10 Million Dollar Export Tower Award\".\nFriction welding machines.\nCNC technology is used by U-JIN Tech Corp both for automatic material transport and in cases where high accuracy is required. Due to the position measuring devices known from CNC milling machines, the length tolerance of the components can be maintained more accurately than with conventional hydraulic machines. It is even possible, to bring the spindle to a standstill in a given position so that the two eyes of a drive shaft can be positioned at an angle to each other.\nThe two spindles of U-JIN's computer numerical controlled double-head friction welding machines are driven by servo motors that allow the angular position of their motor shaft to be controlled, as well as the speed of rotation and acceleration, since they are equipped with position sensors. If the spindles are controlled in the same way as CNC-controlled servo motors, angular accuracies of ±0.5° can be achieved, e.g. at both ends of a cardan shaft.\nFriction welded products.\nAs friction welding operates below the melting point of the materials, even dissimilar material joints can be produced with high tensile strength. In many cases, the tensile strength of the bimetallic joint is higher than that of the softer base material.\nU-JIN's friction welding machines are used industrially for a wide variety of products:", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "27838050", "revid": "46227482", "url": "https://en.wikipedia.org/wiki?curid=27838050", "title": "Tonejet", "text": "Tonejet is a drop-on-demand inkjet printing technology that enables the direct digital deposition of printing ink onto substrates. The Tonejet digital printing process is targeted at commercial and industrial applications.\nTonejet was first disclosed in Patent Cooperation Treaty publication WO 93/11866 dated June 24, 1993, with the inventor named as Luis Lima-Marques assigned to Research Laboratories of Australia Pty. Ltd., in Adelaide, Australia. A number of patents relating to the technology, including United States Patent 6,260,954, have been granted. Research Laboratories of Australia formed a partnership with The Technology Partnership plc, a technology and product development company from the UK, to add hardware development expertise. Tonejet now has its headquarters in Cambridge, UK.\nProcess.\nThe Tonejet process is an electrostatic drop-on-demand deposition technology that enables high-quality images to be printed onto virtually any type of absorbing or non-absorbing substrate at high speed. The Tonejet process consists of electrostatic concentration and ejection of particles from a fluid. The Tonejet print head enables an electric field to be applied to the ink. The Tonejet ink is a key part of the ejection process; it consists of electrically charged conventional pigments in a non-conductive liquid. In the Tonejet printhead, an electric force is applied directly to the charged ink particles. The longer the electric pulse is applied, the more ink is ejected. The Tonejet ejection process concentrates the ink prior to ejecting the droplets onto the substrate, with continuous greyscale control. The Tonejet printhead is a three-dimensional structure consisting of side walls, flow channels and ejectors. An ink meniscus is formed between the side walls and the ejector. The Tonejet printhead is therefore a simple, nozzleless, open structure.\nCommercial products.\nIn late 2007, Tonejet announced that it had produced the world's widest integral printhead for use in an industrial printer. The wide printhead would enable the vast majority of food and drink packaging to be printed in a single pass, thereby bringing substantial logistics and cost savings to the packaging industry.\nIn 2008, Ball Packaging Europe announced that in cooperation with Tonejet, they would supply individually designed beverage cans using the Tonejet process with photo quality, 600 dpi resolution.\nIn June 2010, Air Berlin launched its own line of beverage cans after becoming the first customer for Ball Packaging Europe's technology co-operation with Tonejet. There is some interest particularly in printing cans for the craft beer market.", "Engineering,_Manufacturing": 1.00000453, "qwen": "Yes"}
{"id": "41615704", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=41615704", "title": "3D printing marketplace", "text": "A 3D printing marketplace is a website where users buy, sell and freely share digital 3D printable files for use on 3D printers. They sometimes also offer the ability to print the models and ship them to customers.\nConcept.\nThe market for 3D printers has grown tremendously over the past several years. According to \"Wohlers Report 2018\", 3D printer Market reached 7.3 billions $ in 2017, with +21% growth over the previous year. The market is mostly B2B right now, because 3D printing is still a complex process. But even for SMB or freelance, they cannot develop all the knowledge around this technology, that's why 3D printing marketplace have been developing since the last years.\nThe field of 3D printing is a fascinating field that develops new avenues of creation and engineering. The field is developing rapidly and reaches many industries in the industry as well as mainstream users.\nThe open source community helps with the effort and makes the 3D creative and learning experience accessible to anyone who wishes, while lowering the barriers for the community worldwide.\nIndustries and sectors benefiting from the technology are aerospace, medical (dental, maxillofacial, craniofacial, cosmetic surgery, medical equipment, orthopedics, bio-printing), automobile, engineering, tools, architecture, construction, jewelry, fashion, design, food, art, entertainment and education.\nHow 3D printing marketplaces work.\n3D printing marketplaces are a combination of file sharing websites, with or without a built in e-commerce capability. Designers upload suitable files for 3D printing whilst other users buy or freely download the uploaded files for printing. The marketplaces facilitate the account management, infrastructure, server resources and guarantees safe settlement of payments (e-commerce). Some of the marketplaces also offer additional services such as 3D printing on demand, location of commercial 3D print shops, associated software for model rendering and dynamic viewing of items using packages such as Sketchfab. The most widely used 3D printable file formats as of 2020 are STL, OBJ file, AMF, and 3MF. \nType of 3D printing marketplaces.\nThere are different varieties of 3D printing marketplaces. Some of them like Thingiverse are dedicated to free sharing of 3D printable files. Others, like Shapeways offer a 3D printing service for objects which have been provided for sale by designers. MyMiniFactory offers a combination of these two: their main activity being the free sharing or 3D printable files, they also offer print-on-demand and design-on-demand services. Another category are websites exemplified by Threeding. These offer free and commercial exchange of digital 3D printable files for use on 3D printers but do not directly include 3D printing services themselves. These marketplaces do however, offer integration to databases of 3D printers provided by third parties. These three resources each contain geo-location services to several thousands of registered 3D printers. The two largest personal 3D printers manufacturers Makerbot (part of Stratasys) and Cubify (subsidiary of 3D Systems) offer their own file repositories for sharing, respectively Thingiverse and Cubify Store. For professional 3D printing needs there are platforms which offer a reverse-bid style auction interface, an integrated escrow payment system and many features specifically tailored for B2B transactions.\nCopyright concerns.\nCurrent intellectual property (IP) legislation in the developed countries does not explicitly regulate 3D printing. This creates numerous questions about the IP status of 3D printing marketplaces. Some analysts predict that 3D printing marketplaces will be \"the next Napster\". Most marketplaces remain conservative on this topic. Most large 3D printing marketplaces also have procedures for copyright complaints. Further development of 3D printing and more new marketplaces for file sharing will most probably cause copyright to become a significant issue in them.", "Engineering,_Manufacturing": 0.9990928173, "qwen": "Yes"}
{"id": "41652230", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=41652230", "title": "Rheological weldability", "text": "Rheological weldability (RW) of thermoplastics considers the materials flow characteristics in determining the weldability of the given material. The process of welding thermal plastics requires three general steps, first is surface preparation. The second step is the application of heat and pressure to create intimate contact between the components being joined and initiate inter-molecular diffusion across the joint and the third step is cooling. RW can be used to determine the effectiveness of the second step of the process for given materials.\nRheology.\nRheology is the study of material flow as well as how a material deforms under an applied force. Rheological properties are typically applied to Non-Newtonian fluids but can also be applied to soft solids such as thermoplastics at elevated temperatures experienced during the welding process. The material properties associated with the rheological behavior include viscosity, elasticity, plasticity, viscoelasticity, and the material's activation energy as a function of temperature.\nRheological properties.\nTo understand the rheological properties of a material it is also important to recognize the stress strain relationship for that material at varying temperatures.  This relationship is attained through experimental measurement of the resultant deformation as a function of an applied force.\nInfluences of microstructure and composition.\nA material's rheological behavior is influenced by a combination of the material's microstructure, its composition, the temperature and pressure acting on the material at a given time.  The rheological and viscoelastic properties of a polymer melt are sensitive to the material's molecular structure; including molecular weight distribution and effects of branching. As a result, rheology can be used to develop relationships between differing material combinations.\nDetermining microstructure.\nMelt rheology has shown to be an accurate method in determining the polymer's molecular structure. This is beneficial in determining weld compatibility between materials; as materials with drastically different flow characteristics will be more difficult to join compared to those with more closely matched viscosity and melting temperature properties. This information can also be used to help determine weld parameters for the given welding process to be used.\nViscosity.\nRegarding sessile drop technique, wetting is characterized by degree of interfacial contact and quantified via contact angle (\"θ\"c) of a liquid on a solid surface at equilibrium, as shown in Fig. 1. Interrelation between contact angle and surface tensions at equilibrium is given by the Young equation:\nWhere:\nFor perfectly good wetting, contact angle (\"θ\"c) at equilibrium should be minimized. However, it is valid only at equilibrium, and rate of the equilibrium depends on the balance between driving force of wetting and viscosity of the liquid. In the case of polymer melts, viscosity can be very high and it may take a long time to reach the equilibrium contact angle (dynamic contact angle is likely higher than the contact angle at equilibrium).\nConsequently, for the evaluation of weldability, viscosity of molten thermoplastics (polymer melts) have to be taken into account since welding is a rapid process. It can be said that the lower the viscosity during welding process (at welding temperature and pressure), the better the weldability.\nRecalling that viscosity (\"η\") decreases with increasing temperature (\"T\") and shear rate (formula_6) for most polymer melts, weldability is better where temperature and shear rate (movement) are higher within the entire cross-section of the welding region.\nElasticity.\nElasticity is best described by stretching a rubber band. As one pulls on the rubber band it stretches and when the pulling force is lessened and finally removed the rubber band returns to its original length. Similarly when a force or load is applied to most materials the material deforms and as long as the force has not exceeded the material's yield strength the material will return to its original shape when the force or load is removed. The material property associated with a material's Elasticity is called Young's modulus and the relationship between the amount of deformation for a given load is described by Hooke's Law.\nWhere formula_8, or the stress experienced by the material and equals the change in length divided by the original length multiplied by the material's elasticity or Yong's modulus \"E\".\nPlasticity.\nA material's ability to deform elastically while resisting flow is called plasticity. When an applied force or load exceeds the material's yield strength the material begins to deform plastically and the material will no longer return to its original shape. During the welding processes of polymers, this is experienced at temperatures above the glass transition temperature and below the material's melting temperature.\nViscoelasticity.\nLinear viscoelasticity.\nLinear viscoelastic behavior can be observed when a material experiences small and slow deformation at very slow shear rates, where the relaxation process has sufficient time to keep up with the process. This can also be experienced at the onset of larger deformation forces.\nNonlinear viscoelasticity.\nA polymer's response to fast and large deformation forces is a non linear behavior and is more representative of the reactions experienced during the welding processes.\nKnowing the viscoelastic behavior allows for adjustments to temperature and pressure during the weld process in order to improve the weld quality.\nActivation energy.\nDuring operation of a welding process, the softened or molten portion of thermoplastics (polymer articles) is able to flow through the interface. Less flow results in less diffusion at the interface and lower weld strength. In order for a polymer melt to flow, macromolecular chain segments must be able to move. When the chain segments obtain sufficient thermal energy to overcome the energy barrier, they begin to move readily. The energy barrier is called activation energy (\"E\"a). It can be said that if a polymer’s absolute value of activation energy (|\"E\"a|) is lower, its weldability becomes better.\nUsing viscosity-shear rate (formula_10) data at various temperatures for a polymer, activation energy (\"E\"a) can be calculated via Arrhenius equation:\nWhere:\nThe absolute value of the activation energy (|\"E\"a|) can be calculated by taking the natural logarithm of the Arrhenius equation. (see Arrhenius equation).\nWeldability of polymers.\nWelding of polymers is dependent on intimate contact resulting in molecular diffusion and chain entanglement across the weld joint.  This action requires the polymer to be in a molten state where the melt viscosity and flow behavior have a drastic influence on the amount of diffusion and entanglement. Therefore, the rheological weldability is best between materials with matching or very similar melting temperatures and melt viscosity. Also as a material's viscosity and activation energies are reduced the weldability of that material is improved. For example, welding semi-crystalline to compatible semi-crystalline material and amorphous to compatible amorphous material have exhibited the best results.  While a rheological analysis can provide reasonable insight to a material's weldability, in most cases production welding is typically prefaced with a series of tests to verify compatibility between both base materials as well as the process employed.\nSimilar to welding metals, the solidified polymer weld experiences residual stresses inherent to the joining process.  With polymers, these residual stresses are in part due to the squeeze flow rate leading to a specific molecular alignment direction, ultimately influencing the weld strength and overall quality.  Having a thorough understanding of the rheological properties of the materials being joined can aid in determining the resultant residual stresses and in turn provide insight to processing methods that could reduce these stresses.", "Engineering,_Manufacturing": 0.9992637038, "qwen": "Yes"}
{"id": "41652892", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=41652892", "title": "Plastic joining", "text": "Plastic joining is the method of joining semi-finished products of plastic materials together or to other materials as a fabrication process or damage repair. Joining methods can be classified into three categories:\nMechanical fastening.\nMechanical fastening methods can offer an advantage of disassembly, but have drawbacks arising from stress concentrations, galvanic corrosion, mismatch of thermal expansion coefficients, etc. which rivets, screws and ropes can introduce (see fasteners).\nAdhesive bonding.\nAdhesive bonding, which involves a chemical process where a substance is used to create a bond between two materials, is problematic because of extensive surface preparation, long curing time, the difficulty of bonding adhesive materials to plastics, etc.\nWelding.\nWelding can eliminate these shortcomings largely, but its applications are restricted to thermoplastics.", "Engineering,_Manufacturing": 0.9997869134, "qwen": "Yes"}
{"id": "1496597", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=1496597", "title": "Friction stir welding", "text": "Friction stir welding (FSW) is a solid-state joining process that uses a non-consumable tool to join two facing workpieces without melting the workpiece material. Heat is generated by friction between the rotating tool and the workpiece material, which leads to a softened region near the FSW tool. While the tool is traversed along the joint line, it mechanically intermixes the two pieces of metal, and forges the hot and softened metal by the mechanical pressure, which is applied by the tool, much like joining clay, or dough. It is primarily used on wrought or extruded aluminium and particularly for structures which need very high weld strength. FSW is capable of joining aluminium alloys, copper alloys, titanium alloys, mild steel, stainless steel and magnesium alloys. More recently, it was successfully used in welding of polymers. In addition, joining of dissimilar metals, such as aluminium to magnesium alloys, has been recently achieved by FSW. Application of FSW can be found in modern shipbuilding, trains, and aerospace applications.\nThe general idea was patented in the Soviet Union by one Yu. Klimenko in 1967, but it wasn't developed into a commercial technology back then. It was experimentally proven and commercialized at The Welding Institute (TWI) in the UK in 1991. TWI held patents on the process, the first being the most descriptive.\nPrinciple of operation.\nFriction stir welding is performed with a rotating cylindrical tool which has a profiled pin (also known a probe) having a diameter smaller than the diameter of its shoulder. During welding the tool is fed into a butt joint between two clamped workpieces, until the probe pierces into the workpiece and its shoulder touches the surface of the workpieces. The probe is slightly shorter than the weld depth required, with the tool shoulder riding atop the work surface. After a short dwell time, the tool is moved forward along the joint line at the pre-set welding speed.\nFrictional heat is generated between the wear-resistant tool and the work pieces. This heat, along with that generated by the mechanical mixing process and the adiabatic heat within the material, cause the stirred materials to soften without melting. As the tool is moved forward, a special profile on the probe forces plasticised material from the leading face to the rear, where the high forces assist in a forged consolidation of the weld.\nThis process of the tool traversing along the weld line in a plasticised tubular shaft of metal results in severe solid-state deformation involving dynamic recrystallization of the base material.\nMicro-structural features.\nThe solid-state nature of the FSW process, combined with its unusual tool shape and asymmetric speed profile, results in a highly characteristic micro-structure. The micro-structure can be broken up into the following zones:\nAdvantages and limitations.\nThe solid-state nature of FSW leads to several advantages over fusion welding methods, as problems associated with cooling from the liquid phase are avoided. Issues such as porosity, solute redistribution, solidification cracking and liquation cracking do not arise during FSW. In general, FSW has been found to produce a low concentration of defects and is very tolerant to variations in parameters and materials.\nNevertheless, FSW is associated with a number of unique defects if it isn't done properly. Insufficient weld temperatures, due to low rotational speeds or high traverse speeds, for example, mean that the weld material is unable to accommodate the extensive deformation during welding. This may result in long, tunnel-like defects running along the weld, which may occur on the surface or subsurface. Low temperatures may also limit the forging action of the tool and so reduce the continuity of the bond between the material from each side of the weld. The light contact between the material has given rise to the name \"kissing bond\". This defect is particularly worrying, since it is very difficult to detect using nondestructive methods such as X-ray or ultrasonic testing. If the pin is not long enough or the tool rises out of the plate, then the interface at the bottom of the weld may not be disrupted and forged by the tool, resulting in a lack-of-penetration defect. This is essentially a notch in the material, which can be a potential source of fatigue cracks.\nA number of potential advantages of FSW over conventional fusion-welding processes have been identified:\nHowever, some disadvantages of the process have been identified:\nImportant welding parameters.\nTool design.\nThe design of the tool is a critical factor, as a good tool can improve both the quality of the weld and the maximal possible welding speed.\nIt is desirable that the tool material be sufficiently strong, tough, and hard wearing at the welding temperature. Further, it should have a good oxidation resistance and a low thermal conductivity to minimise heat loss and thermal damage to the machinery further up the drive train. Hot-worked tool steel such as AISI H13 has proven perfectly acceptable for welding aluminium alloys within thickness ranges of 0.5–50 mm but more advanced tool materials are necessary for more demanding applications such as highly abrasive metal matrix composites or higher-melting-point materials such as steel or titanium.\nImprovements in tool design have been shown to cause substantial improvements in productivity and quality. TWI has developed tools specifically designed to increase the penetration depth and thus increasing the plate thicknesses that can be successfully welded. An example is the \"whorl\" design that uses a tapered pin with re-entrant features or a variable-pitch thread to improve the downwards flow of material. Additional designs include the Triflute and Trivex series. The Triflute design has a complex system of three tapering, threaded re-entrant flutes that appear to increase material movement around the tool. The Trivex tools use a simpler, non-cylindrical, pin and have been found to reduce the forces acting on the tool during welding.\nThe majority of tools have a concave shoulder profile, which acts as an escape volume for the material displaced by the pin, prevents material from extruding out of the sides of the shoulder and maintains downwards pressure and hence good forging of the material behind the tool. The Triflute tool uses an alternative system with a series of concentric grooves machined into the surface, which are intended to produce additional movement of material in the upper layers of the weld.\nWidespread commercial applications of friction stir welding process for steels and other hard alloys such as titanium alloys will require the development of cost-effective and durable tools. Material selection, design and cost are important considerations in the search for commercially useful tools for the welding of hard materials. Work is continuing to better understand the effects of tool material's composition, structure, properties and geometry on their performance, durability and cost.\nTool rotation and traverse speeds.\nThere are two tool speeds to be considered in friction-stir welding; how fast the tool rotates and how quickly it traverses along the interface. These two parameters have considerable importance and must be chosen with care to ensure a successful and efficient welding cycle. The relationship between the rotation speed, the welding speed and the heat input during welding is complex, but in general, it can be said that increasing the rotation speed or decreasing the traverse speed will result in a hotter weld. In order to produce a successful weld, it is necessary that the material surrounding the tool is hot enough to enable the extensive plastic flow required and minimize the forces acting on the tool. If the material is too cold, then voids or other flaws may be present in the stir zone and in extreme cases the tool may break.\nExcessively high heat input, on the other hand, may be detrimental to the final properties of the weld. Theoretically, this could even result in defects due to the liquation of low-melting-point phases (similar to liquation cracking in fusion welds). These competing demands lead onto the concept of a \"processing window\": the range of processing parameters viz. tool rotation and traverse speed, that will produce a good quality weld. Within this window the resulting weld will have a sufficiently high heat input to ensure adequate material plasticity but not so high that the weld properties are excessively deteriorated.\nTool tilt and plunge depth.\nThe plunge depth is defined as the depth of the lowest point of the shoulder below the surface of the welded plate and has been found to be a critical parameter for ensuring weld quality. Plunging the shoulder below the plate surface increases the pressure below the tool and helps ensure adequate forging of the material at the rear of the tool. Tilting the tool by 2–4 degrees, such that the rear of the tool is lower than the front, has been found to assist this forging process. The plunge depth needs to be correctly set, both to ensure the necessary downward pressure is achieved and to ensure that the tool fully penetrates the weld. Given the high loads required, the welding machine may deflect and so reduce the plunge depth compared to the nominal setting, which may result in flaws in the weld. On the other hand, an excessive plunge depth may result in the pin rubbing on the backing plate surface or a significant undermatch of the weld thickness compared to the base material. Variable-load welders have been developed to automatically compensate for changes in the tool displacement, while TWI have demonstrated a roller system that maintains the tool position above the weld plate.\nWelding forces.\nDuring welding, a number of forces will act on the tool:\nIn order to prevent tool fracture and to minimize excessive wear and tear on the tool and associated machinery, the welding cycle is modified so that the forces acting on the tool are as low as possible, and abrupt changes are avoided. In order to find the best combination of welding parameters, it is likely that a compromise must be reached, since the conditions that favour low forces (e.g. high heat input, low travel speeds) may be undesirable from the point of view of productivity and weld properties.\nFlow of material.\nEarly work on the mode of material flow around the tool used inserts of a different alloy, which had a different contrast to the normal material when viewed through a microscope, in an effort to determine where material was moved as the tool passed.\nThe data was interpreted as representing a form of in-situ extrusion, where the tool, backing plate and cold base material form the \"extrusion chamber\", through which the hot, plasticised material is forced. In this model the rotation of the tool draws little or no material around the front of the probe; instead, the material parts in front of the pin and passes down either side. After the material has passed the probe, the side pressure exerted by the \"die\" forces the material back together, and consolidation of the joint occurs, as the rear of the tool shoulder passes overhead and the large down force forges the material.\nMore recently, an alternative theory has been advanced that advocates considerable material movement in certain locations. This theory holds that some material does rotate around the probe, for at least one rotation, and it is this material movement that produces the \"onion-ring\" structure in the stir zone. The researchers used a combination of thin copper strip inserts and a \"frozen pin\" technique, where the tool is rapidly stopped in place. They suggested that material motion occurs by two processes:\nThe primary advantage of this explanation is that it provides a plausible explanation for the production of the onion-ring structure.\nThe marker technique for friction stir welding provides data on the initial and final positions of the marker in the welded material. The flow of material is then reconstructed from these positions. Detailed material flow field during friction stir welding can also be calculated from theoretical considerations based on fundamental scientific principles. Material flow calculations are routinely used in numerous engineering applications. Calculation of material flow fields in friction stir welding can be undertaken both using comprehensive numerical simulations or simple but insightful analytical equations. The comprehensive models for the calculation of material flow fields also provide important information such as geometry of the stir zone and the torque on the tool. The numerical simulations have shown the ability to correctly predict the results from marker experiments and the stir zone geometry observed in friction stir welding experiments.\nGeneration and flow of heat.\nFor any welding process, it is, in general, desirable to increase the travel speed and minimise the heat input, as this will increase productivity and possibly reduce the impact of welding on the mechanical properties of the weld. At the same time, it is necessary to ensure that the temperature around the tool is sufficiently high to permit adequate material flow and prevent flaws or tool damage.\nWhen the traverse speed is increased, for a given heat input, there is less time for heat to conduct ahead of the tool, and the thermal gradients are larger. At some point the speed will be so high that the material ahead of the tool will be too cold, and the flow stress too high, to permit adequate material movement, resulting in flaws or tool fracture. If the \"hot zone\" is too large, then there is scope to increase the traverse speed and hence productivity.\nThe welding cycle can be split into several stages, during which the heat flow and thermal profile will be different: \nHeat generation during friction-stir welding arises from two main sources: friction at the surface of the tool and the deformation of the material around the tool. The heat generation is often assumed to occur predominantly under the shoulder, due to its greater surface area, and to be equal to the power required to overcome the contact forces between the tool and the workpiece. The contact condition under the shoulder can be described by sliding friction, using a friction coefficient μ and interfacial pressure \"P\", or sticking friction, based on the interfacial shear strength at an appropriate temperature and strain rate. Mathematical approximations for the total heat generated by the tool shoulder \"Q\"total have been developed using both sliding and sticking friction models:\nwhere ω is the angular velocity of the tool, \"R\"shoulder is the radius of the tool shoulder, and \"R\"pin is that of the pin. Several other equations have been proposed to account for factors such as the pin, but the general approach remains the same.\nA major difficulty in applying these equations is determining suitable values for the friction coefficient or the interfacial shear stress. The conditions under the tool are both extreme and very difficult to measure. To date, these parameters have been used as \"fitting parameters\", where the model works back from measured thermal data to obtain a reasonable simulated thermal field. While this approach is useful for creating process models to predict, for example, residual stresses, it is less useful for providing insights into the process itself.\nApplications.\nThe FSW process has initially been patented by TWI in most industrialised countries and licensed for over 183 users. Friction stir welding and its variants friction stir spot welding and friction stir processing are used for the following industrial applications: shipbuilding and offshore,\naerospace, automotive, rolling stock for railways, general fabrication, robotics, and computers.\nShipbuilding and offshore.\nTwo Scandinavian aluminium extrusion companies were the first to apply FSW commercially to the manufacture of fish freezer panels at Sapa in 1996, as well as deck panels and helicopter landing platforms at Marine Aluminium Aanensen. Marine Aluminium Aanensen subsequently merged with Hydro Aluminium Maritime to become Hydro Marine Aluminium. Some of these freezer panels are now produced by Riftec and Bayards. In 1997 two-dimensional friction stir welds in the hydrodynamically flared bow section of the hull of the ocean viewer vessel \"The Boss\" were produced at Research Foundation Institute with the first portable FSW machine. The \"Super Liner Ogasawara\" at Mitsui Engineering and Shipbuilding is the largest friction stir welded ship so far. The \"Sea Fighter\" of Nichols Bros and the \"Freedom\"-class Littoral Combat Ships contain prefabricated panels by the FSW fabricators Advanced Technology and Friction Stir Link, Inc. respectively. The \"Houbei\"-class missile boat has friction stir welded rocket launch containers of China Friction Stir Centre. HMNZS \"Rotoiti\" in New Zealand has FSW panels made by Donovans in a converted milling machine. Various companies apply FSW to armor plating for amphibious assault ships.\nAerospace.\nUnited Launch Alliance applies FSW to the Delta II, Delta IV, Atlas V, and the new Vulcan expendable launch vehicles along with their Cryogenic Upper Stages, and the first of these with a friction stir welded interstage module was launched in 1999. The process was also used for the Space Shuttle external tank, for Ares I until the project was canceled in 2012, the SLS Core which replaced the Ares, and for the Orion Crew Vehicle test article and the current model of the Orion at NASA, as well as Falcon 1 and Falcon 9 rockets at SpaceX. The toe nails for ramp of Boeing C-17 Globemaster III cargo aircraft by Advanced Joining Technologies and the cargo barrier beams for the Boeing 747 Large Cargo Freighter were the first commercially produced aircraft parts. FAA-approved wings and fuselage panels of the Eclipse 500 aircraft were made at Eclipse Aviation, and this company delivered 259 friction stir welded business jets, before they were forced into Chapter 7 liquidation. Floor panels for Airbus A400M military aircraft are now made by Pfalz Flugzeugwerke and Embraer used FSW for the Legacy 450 and 500 Jets Friction stir welding also is employed for fuselage panels on the Airbus A380. BRÖTJE-Automation uses friction stir welding for gantry production machines developed for the aerospace sector, as well as other industrial applications.\nAutomotive.\nAluminium engine cradles and suspension struts for stretched Lincoln Town Cars were the first automotive parts that were friction stir welded at Tower Automotive, who use the process also for the engine tunnel of the Ford GT. A spin-off of this company is called Friction Stir Link, Inc. and successfully exploits the FSW process, e.g. for the flatbed trailer \"Revolution\" of Fontaine Trailers. In Japan FSW is applied to suspension struts at Showa Denko and for joining of aluminium sheets to galvanized steel brackets for the boot (trunk) lid of the Mazda MX-5. Friction stir spot welding is successfully used for the bonnet (hood) and rear doors of the Mazda RX-8 and the boot lid of the Toyota Prius. Wheels are friction stir welded at Simmons Wheels, UT Alloy Works and Fundo. Rear seats for the Volvo V70 are friction stir welded at Sapa, HVAC pistons at Halla Climate Control and exhaust gas recirculation coolers at Pierburg. Tailor welded blanks are friction stir welded for the Audi R8 at Riftec. The B-column of the Audi R8 Spider is friction stir welded from two extrusions at Hammerer Aluminium Industries in Austria. The front subframe of the 2013 Honda Accord was friction stir welded to join aluminum and steel halves.\nRailways.\nSince 1997 roof panels were made from aluminium extrusions at Hydro Marine Aluminium with a bespoke 25 m long FSW machine, e.g. for DSB class SA-SD trains of Alstom LHB. Curved side and roof panels for the Victoria line trains of London Underground, side panels for Bombardier Electrostar trains at Sapa Group and side panels for Alstom's British Rail Class 390 Pendolino trains are made at Sapa Group. Japanese commuter and express A-trains, and British Rail Class 395 trains are friction stir welded by Hitachi, while Kawasaki applies friction stir spot welding to roof panels and Sumitomo Light Metal produces Shinkansen floor panels. Innovative FSW floor panels are made by Hammerer Aluminium Industries in Austria for the Stadler Kiss double decker rail cars, to obtain an internal height of 2 m on both floors and for the new car bodies of the Wuppertal Suspension Railway.\nHeat sinks for cooling high-power electronics of locomotives are made at Sykatek, EBG, Austerlitz Electronics, EuroComposite, Sapa and , and are the most common application of FSW due to the excellent heat transfer.\nFabrication.\nFaçade panels and cathode sheets are friction stir welded at AMAG and Hammerer Aluminium Industries, including friction stir lap welds of copper to aluminium. Bizerba meat slicers, Ökolüfter HVAC units and Siemens X-ray vacuum vessels are friction stir welded at Riftec. Vacuum valves and vessels are made by FSW at Japanese and Swiss companies. FSW is also used for the encapsulation of nuclear waste at SKB in 50-mm-thick copper canisters. Pressure vessels from ø1 m semispherical forgings of 38.1 mm thick aluminium alloy 2219 at Advanced Joining Technologies and Lawrence Livermore Nat Lab. Friction stir processing is applied to ship propellers at Friction Stir Link, Inc. and to hunting knives by DiamondBlade. Bosch uses it in Worcester for the production of heat exchangers.\nRobotics.\nKUKA Robot Group has adapted its KR500-3MT heavy-duty robot for friction stir welding via the DeltaN FS tool. The system made its first public appearance at the EuroBLECH show in November 2012.\nPersonal computers.\nApple applied friction stir welding on the 2012 iMac to effectively join the bottom to the back of the device.\nJoining of aluminum 3D printing material.\nFSW is proven able to be used as one of the methods to join the metal 3D printing materials. By using proper FSW tools and correct parameter setting a sound and defect-free weld can be produced in order to joint the metal 3D printing materials. Besides, the FSW tools must be harder than the materials that need to weld. The most important parameters in FSW are the rotation of probe, traverse speed, spindle tilt angle and target depth. The weld joint efficiency of FSW on the 3D printing metal can reach up to 83.3% compared to its base materials strength.", "Engineering,_Manufacturing": 1.0000066757, "qwen": "Yes"}
{"id": "41469909", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=41469909", "title": "Higashi-Fuji Technical Center", "text": " is a Toyota research and development facility in Susono, Shizuoka, Japan. The facility was established in November 1966.\nNotably, the center contains an advanced driving simulation housed inside a diameter dome with an actual car inside. The simulator is used to analyse driver behaviors in order to improve safety. Higashi-Fuji also includes a crash test building.", "Engineering,_Manufacturing": 0.9850497246, "qwen": "Yes"}
{"id": "41489324", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=41489324", "title": "Intelligent maintenance system", "text": "An intelligent maintenance system (IMS) is a system that utilizes collected data from machinery in order to predict and prevent potential failures in them. The occurrence of failures in machinery can be costly and even catastrophic. In order to avoid failures, there needs to be a system which analyzes the behavior of the machine and provides alarms and instructions for preventive maintenance. Analyzing the behavior of the machines has become possible by means of advanced sensors, data collection systems, data storage/transfer capabilities and data analysis tools. These are the same set of tools developed for prognostics. The aggregation of data collection, storage, transformation, analysis and decision making for smart maintenance is called an intelligent maintenance system (IMS).\nDefinition.\nAn intelligent maintenance system is a system that utilizes data analysis and decision support tools to predict and prevent the potential failure of machines. The recent advancement in information technology, computers, and electronics have facilitated the design and implementation of such systems.\nThe key research elements of intelligent maintenance systems consist of:\nE-manufacturing and e-maintenance.\nWith evolving applications of tether-free communication technologies (e.g. Internet) e-intelligence is having a larger impact on industries. Such impact has become a driving force for companies to shift the manufacturing operations from traditional factory integration practices towards an e-factory and e-supply chain philosophy. Such change is transforming the companies from local factory automation to global business automation. The goal of e-manufacturing is, from the plant floor assets, to predict the deviation of the quality of the products and possible loss of any equipment. This brings about the predictive maintenance capability of the machines.\nThe major functions and objectives of e-manufacturing are: “(a) provide a transparent, seamless and automated information exchange process to enable an only handle information once (OHIO) environment; (b) improve the utilization of plant floor assets using a holistic approach combining the tools of predictive maintenance techniques; (c) links entire supply chain management (SCM) operation and asset optimization; and (d) deliver customer services using the latest predictive intelligence methods and tether-free technologies”.\nThe e-Maintenance infrastructure consists of several information sectors:", "Engineering,_Manufacturing": 1.0000085831, "qwen": "Yes"}
{"id": "60126473", "revid": "5450916", "url": "https://en.wikipedia.org/wiki?curid=60126473", "title": "Thulin N", "text": "The Thulin N was a prototype Swedish scout aircraft built in the late 1910s.\nDesign and development.\nThe Thulin N was a two-seat biplane. Both the upper and lower wings were fitted with knuckles which were connected by a push rod. The fuselage was provided with an open cockpit where one was placed in a tandem location. The fuselage is made of a lattice construction of welded steel pipes . The wheel ground was fixed with a spur spring under the height knob. Although the Swedish military asked Thulin to use a 150-hp Benz engine as the powerplant, Thulin opted for a Thulin G rotary engine.", "Engineering,_Manufacturing": 0.9999867678, "qwen": "Yes"}
{"id": "18460335", "revid": "35498457", "url": "https://en.wikipedia.org/wiki?curid=18460335", "title": "Ramp-up", "text": "Ramp-up is a term used in economics and business to describe an increase in a firm's production ahead of anticipated increases in product demand. Alternatively, ramp-up describes the period from completed initial product development to maximum capacity utilization, characterized by product and process experimentation and improvements. \nRamp-up in the first sense often occurs when a company strikes a deal with a distributor, retailer, or producer, which will substantially increase product demand. For example, in June, 2008, after launching a joint venture with Guangzhou Automobile, Toyota announced that it would \"ramp up\" production in China to meet expected increases in market demand by constructing a plant in Guangdong, which would produce some 120,000 additional Camry sedans. In the consumer electronics industry, manufacturers often ramp-up production in the early fall to meet demand during the holiday selling season.\nAs ramp-up is typical in early stages of firm or market development, the term and process is widely associated with venture capital, which seek to rapidly increase rate of return on investment, just prior to exit. For example, Wrightspeed, the producer of the X1 electric car prototype, began to seek out capital in order to hire on 50 well-trained employees in order to \"ramp up\" production in anticipation of sales successes.\nRamp up may also refer to how quickly dispatchable generation from power plants can increase, and ramp down by how quickly it can decrease whilst still remaining operational (not shutting down), with \"ramp\" being either way.", "Engineering,_Manufacturing": 0.9984400868, "qwen": "Yes"}
{"id": "18468216", "revid": "2038267", "url": "https://en.wikipedia.org/wiki?curid=18468216", "title": "Shearing (manufacturing)", "text": "Shearing, also known as die cutting, is a process that cuts stock without the formation of chips or the use of burning or melting. Strictly speaking, if the cutting blades are straight the process is called shearing; if the cutting blades are curved then they are shearing-type operations. The most commonly sheared materials are in the form of sheet metal or plates. However, rods can also be sheared. Shearing-type operations include blanking, piercing, roll slitting, and trimming. It is used for metal, fabric, paper and plastics.\nPrinciple.\nA punch (or moving blade) is used to push a workpiece against the die (or fixed blade), which is fixed. Usually, the clearance between the two is 5 to 40% of the thickness of the material, but dependent on the material. Clearance is defined as the separation between the blades, measured at the point where the cutting action takes place and perpendicular to the direction of blade movement. It affects the finish of the cut (burr) and the machine's power consumption. This causes the material to experience highly localized shear stresses between the punch and die. The material will then fail when the punch has moved 15 to 60% of the thickness of the material because the shear stresses are greater than the shear strength of the material and the remainder of the material is torn.\nTwo distinct sections can be seen on a sheared workpiece, the first part being plastic deformation and the second being fractured. Because of normal inhomogeneities in materials and inconsistencies in clearance between the punch and die, the shearing action does not occur in a uniform manner. The fracture will begin at the weakest point and progress to the next weakest point until the entire workpiece has been sheared; this is what causes the rough edge. The rough edge can be reduced if the workpiece is clamped from the top with a die cushion. Above a certain pressure, the fracture zone can be completely eliminated. However, the sheared edge of the workpiece will usually experience work-hardening and cracking. If the workpiece has too much clearance, then it may experience roll-over or heavy burring.\nTolerances and surface finish.\nWhen shearing a sheet, the typical tolerance is +0.1 inch or −0.1 inch, but it is feasible to get the tolerance to within +0.005 inch or −0.005 inch. While shearing a bar and angle, the typical tolerance is +0.06 inch or −0.06 inch, but it is possible to get the tolerance to +0.03 inch or −0.03 inches. Surface finishes typically occur within the 250 to 1000 microinches range but can range from 125 to 2000 microinches. A secondary operation is required if one wants better surfaces than this.", "Engineering,_Manufacturing": 0.9996581078, "qwen": "Yes"}
{"id": "27679", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=27679", "title": "Soldering iron", "text": "A soldering iron is a hand tool used in soldering. It supplies heat to melt solder so that it can flow into the joint between two workpieces.\nA soldering iron is composed of a heated metal tip (the \"bit\") and an insulated handle. Heating is often achieved electrically, by passing an electric current (supplied through an electrical cord or battery cables) through a resistive heating element. Cordless irons can be heated by combustion of gas stored in a small tank, often using a catalytic heater rather than a flame. Simple irons, less commonly used today than in the past, were simply a large copper \"bit\" on a handle, heated in a flame.\nSolder melts at approximately . Soldering irons are designed to reach a temperature range of . \nSoldering irons are most often used for installation, repairs, and limited production work in electronics assembly. High-volume production lines use other soldering methods. Large irons may be used for soldering joints in sheet metal objects. Less common uses include pyrography (burning designs into wood) and plastic welding (as an alternative to ultrasonic welding).\nHistory.\nBefore the development of electric soldering irons, the typical soldering iron consisted of a copper block, with an appropriately shaped point, supported on an iron rod and held in a wood handle. Immediately before use, the iron was heated over a fire or in a charcoal brazier, and it had to be reheated whenever it became too cool for use. Soldering irons were primarily used by tinsmiths and coppersmiths to work with thin sheet metal.\nA large copper block was required in order to have sufficient thermal capacity to provide\nuseful heat after removal from the fire, and copper is expensive. This led to the development of\nsoldering irons that had a small copper tip attached to an inexpensive cast-iron block. Some irons even had removable and replaceable copper tips.\nThe first electric soldering iron had a very lightweight platinum tip heated by electric current flowing through the tip itself. By 1889, electric soldering irons were being developed with a resistance wire wrapped around the back end of the copper head and enclosed in a protective shell. Alternatively, the heating element could be enclosed in a relatively light-weight hollow copper head. \nIn 1894, the American Electrical Heater Company began manufacturing electrical soldering irons on a large scale in Detroit. They started producing them shortly after American Beauty released their line of soldering irons.\nIn 1905, \"Scientific American Magazine,\" published a tutorial on making a soldering iron that\nclearly explains how early irons were made.\nIn 1921, a German company founded by Ernst Sachs developed an electrical soldering iron similar to American Electrical Heater Company iron.\nTypes.\nSimple iron.\nFor electrical and electronics work, a low-power iron, a power rating between 15 and 35 watts, is used. Higher ratings are available, but do not run at higher temperature; instead there is more heat available for making soldered connections to things with large thermal capacity, for example, a metal chassis. Some irons are temperature-controlled, running at a fixed temperature in the same way as a soldering station, with higher power available for joints with large heat capacity. Simple irons run at an uncontrolled temperature determined by thermal equilibrium; when heating something large their temperature drops.\nA variation is the Scope soldering iron, common in Australia, which operates from a low-voltage source such as transformer or battery, and heats in seconds when the user pushes the thumb-guard, which then acts as a heat controller.\nCordless iron.\nSmall irons heated by a battery, or by combustion of a gas such as butane in a small self-contained tank, can be used when electricity is unavailable or cordless operation is required. The operating temperature of these irons is not regulated directly; gas irons may change power by adjusting gas flow. Gas-powered irons may have interchangeable tips including different size soldering tips, hot knife for cutting plastics, miniature blow-torch with a hot flame, and small hot air blower for such applications as shrinking heat shrink tubing.\nTemperature-controlled soldering iron.\nSimple soldering irons reach a temperature determined by thermal equilibrium, dependent upon power input and cooling by the environment and the materials it comes into contact with. The iron temperature will drop when in contact with a large mass of metal such as a chassis; a small iron will lose too much temperature to solder a large connection. More advanced irons for use in electronics have a mechanism with a temperature sensor and method of temperature control to keep the tip temperature steady; more power is available if a connection is large. Temperature-controlled irons may be free-standing, or may comprise a head with heating element and tip, controlled by a base called a soldering station, with control circuitry and temperature adjustment and sometimes display.\nA variety of means are used to control temperature. The simplest of these is a variable power control, much like a light dimmer, which changes the equilibrium temperature of the iron without automatically measuring or regulating the temperature. Another type of system uses a thermostat, often inside the iron's tip, which automatically switches power on and off to the element. A thermal sensor such as a thermocouple may be used in conjunction with circuitry to monitor the temperature of the tip and adjust power delivered to the heating element to maintain a desired temperature. In some models, the firmware for the control circuitry is free software that can be modified by the end-user.\nAnother approach is to use magnetized soldering tips which lose their magnetic properties at a specific temperature, the Curie point. As long as the tip is magnetic, it closes a switch to supply power to the heating element. When it exceeds the design temperature it opens the contacts, cooling until the temperature drops enough to restore magnetisation. More complex Curie-point irons circulate a high-frequency AC current through the tip, using magnetic physics to direct heating only where the surface of the tip drops below the Curie point.\nSoldering station.\nA soldering station has a temperature control and consists of an electrical power supply, control circuitry with provision for user adjustment of temperature and display, and a soldering iron or soldering head with a tip temperature sensor. The station will normally have a stand for the hot iron when not in use, and a wet sponge for cleaning. It is most commonly used for soldering electronic components. Other functions may be combined; for example a rework station, mainly for surface-mount components may have a hot air gun, vacuum pickup tool, and a soldering head; a desoldering station will have a desoldering head with vacuum pump for desoldering through-hole components, and a soldering iron head.\nSoldering tweezers.\nFor soldering and desoldering small surface-mount components with two terminals, such as some links, resistors, capacitors, and diodes, soldering tweezers can be used; they can be either free-standing or controlled from a soldering station. The tweezers have two heated tips mounted on arms whose separation can be manually varied by squeezing gently against spring force, like simple tweezers; the tips are applied to the two ends of the component. The main purpose of the soldering tweezers is to melt solder in the correct place; components are usually moved by simple tweezers or vacuum pickup.\nHot knife.\nA hot knife is a form of soldering iron equipped with a double-edged blade that is situated on a heating element. These tools can reach temperatures of up to 1,000 degrees Fahrenheit (538 degrees Celsius) allowing for cuts of fabric and foam materials without worry of fraying or beading. Hot knives can be utilized in automotive, marine, and carpeting applications, as well as other industrial and personal uses.\nStands.\nA soldering iron stand keeps the iron away from flammable materials, and often also comes with a cellulose sponge and flux pot for cleaning the tip. Some soldering irons for continuous and professional use come as part of a \"soldering station,\" which allows the exact temperature of the tip to be adjusted, kept constant, and sometimes displayed.\nTips.\nMost soldering irons for electronics have interchangeable tips, also known as \"bits\", that vary in size and shape for different types of work. Common tip shapes include: \"bevel\", \"chisel\", and \"conical\". An example of a more specialist tip is spoon or gull wing, which features concavity. See the image for renderings of a few different tip shapes and some of the names given to them.\nPyramid tips with a triangular flat face and chisel tips with a wide flat face are useful for soldering sheet metal. Fine conical or tapered chisel tips are typically used for electronics work. Tips may be straight or have a bend. Concave or wicking tips with a chisel face with a concave well in the flat face to hold a small amount of solder are available. Tip selection depends upon the type of work and access to the joint; soldering of 0.5mm pitch surface-mount ICs, for example, is quite different from soldering a through-hole connection to a large area. A concave tip well is said to help prevent bridging of closely spaced leads; different shapes are recommended to correct bridging that has occurred. Due to patent restrictions not all manufacturers offer concave tips everywhere; in particular there are restrictions in the USA.\nOlder and very cheap irons typically use a bare copper tip, which is shaped with a file or sandpaper. This dissolves gradually into the solder, suffering pitting and erosion of the shape. Copper tips are sometimes filed when worn down. Iron-plated copper tips have become increasingly popular since the 1980s. Because iron is not readily dissolved by molten solder, the plated tip is more durable than a bare copper one, though it will eventually wear out and need replacing. This is especially important when working at the higher temperatures needed for modern lead-free solders. Solid iron and steel tips are seldom used because they store less heat, conduct it poorly, and rusting can break the heating element.\nIron-plated tips may feature a layer of nickel between the copper core and the iron surface. A nickel-chrome outer plating may be used further back from the very tip, as solder does not stick well to this material: this avoids solder wetting parts of the tip where it would be unwanted.\nSome tips have a heater and a thermocouple-based temperature sensor embedded to facilitate a more precise temperature control (TS100 and T12, for instance).\nCleaning.\nWhen the iron tip oxidises and burnt flux accumulates on it, solder no longer wets the tip, impeding heat transfer and making soldering difficult or impossible; tips must be periodically cleaned in use. Such problems happen with all kinds of solder, but are much more severe with the lead-free solders which have become widespread in electronics work, which require higher temperatures than solders containing lead. Exposed iron plating oxidises; if the tip is kept tinned with molten solder oxidation is inhibited. A clean unoxidised tip is tinned by applying a little solder and flux.\nA wet small sponge, often supplied with soldering equipment, can be used to wipe the tip. For lead-free solder a slightly more aggressive cleaning, with brass shavings, can be used. Soldering flux will help to remove oxide; the more active the flux the better the cleaning, although acidic flux used on circuit boards that is not carefully cleaned off will cause corrosion. A tip which is cleaned but not retinned is susceptible to oxidation.\nSoldering iron tips are made of a copper core plated various metals including iron. The copper is used for heat transfer and the other platings are for durability. Copper is very easily corroded, eating away the tip, particularly in lead-free work; iron is not. Cleaning tips requires the removal of oxide without damaging the iron plating and exposing the copper to rapid corrosion. The use of solder already containing a small amount of copper can slow corrosion of copper tips.\nIn cases of severe oxidation not removable by gentler methods, abrasion with something hard enough to remove oxide but not so hard as to scratch the iron plating can be used. A brass wire scourer, brush, or wheel on a bench grinder, can be used with care. Sandpaper and other tools may be used but are likely to damage the plating.\nElectro-static discharge.\nNot all soldering irons are ESD-safe.\nAlthough some manufacturers' mains-powered models are built with the element shaft (and hence the tip) electrically connected to ground via the iron's mains lead, other models' tips may float at arbitrary voltages unless an additional grounding wire is used.\nWattage.\nThe wattage of the soldering iron is one of the most important factors in a soldering iron. Most of the soldering irons used in the electronics have wattage in the range of 20–60 watts. \nTemperature-controlled soldering irons with higher wattage (40 W–60 W) are better than low-wattage irons. It does not mean that temperature-controlled soldering irons with higher wattage apply more heat to the solder joint - it simply means that temperature-controlled soldering irons with higher wattage have more power available to heat the soldering joint if needed.\nOn the other hand, a soldering iron with low wattage (20 W–30 W) can lose heat faster than it can re-heat itself. This may result in poor solder joints, particularly when soldering bigger solder joints or thick wires. ", "Engineering,_Manufacturing": 0.9982478619, "qwen": "Yes"}
{"id": "27995", "revid": "7770027", "url": "https://en.wikipedia.org/wiki?curid=27995", "title": "Supply chain management", "text": "In commerce, supply chain management (SCM) deals with a system of procurement (purchasing raw materials/components), operations management (ensuring the production of high-quality products at high speed with good flexibility and low production cost), logistics and marketing channels, so that the raw materials can be converted into a finished product and delivered to the end customer. A more narrow definition of the supply chain management is the \"design, planning, execution, control, and monitoring of supply chain activities with the objective of creating net value, building a competitive infrastructure, leveraging worldwide logistics, synchronising supply with demand and measuring performance globally\". This can include the movement and storage of raw materials, work-in-process inventory, finished goods, and end to end order fulfilment from the point of origin to the point of consumption. Interconnected, interrelated or interlinked networks, channels and node businesses combine in the provision of products and services required by end customers in a supply chain.\nSupply chain management strives for an integrated, multidisciplinary, multimethod approach. Marketing channels play an important role in supply-chain management. Current research in supply-chain management is concerned with topics related to sustainability, volatility, and risk management, among others. An important concept discussed in SCM is supply chain resilience. Some suggest that the \"people dimension\" of SCM, ethical issues, internal integration, transparency/visibility, and human capital/talent management are topics that have, so far, been underrepresented on the research agenda. SCM is the broad range of activities required to plan, control and execute a product's flow from materials to production to distribution in the most economical way possible. SCM encompasses the integrated planning and execution of processes required to optimize the flow of materials, information and capital in functions that broadly include demand planning, sourcing, production, inventory management and logistics—or storage and transportation.\nAlthough it has the same goals as supply chain engineering, supply chain management is focused on a more traditional management and business based approach, whereas supply chain engineering is focused on a mathematical model based one.\nMission.\nSupply chain management, techniques with the aim of coordinating all parts of SC, from supplying raw materials to delivering and/or resumption of products, tries to minimize total costs with respect to existing conflicts among the chain partners. An example of these conflicts is the interrelation between the sale department desiring to have higher inventory levels to fulfill demands and the warehouse for which lower inventories are desired to reduce holding costs.\nOrigin of the term and definitions.\nIn 1982, Keith Oliver, a consultant at Booz Allen Hamilton, introduced the term \"supply chain management\" to the public domain in an interview for the Financial Times. In 1983 WirtschaftsWoche in Germany published for the first time the results of an implemented and so called \"Supply Chain Management project\", led by Wolfgang Partsch.\nIn the mid-1990s, the term \"supply chain management\" gained currency when a flurry of articles and books came out on the subject. Supply chains were originally defined as encompassing all activities associated with the flow and transformation of goods from raw materials through to the end user, as well as the associated information flows. Supply-chain management was then further defined as the integration of supply chain activities through improved supply-chain relationships to achieve a competitive advantage.\nIn the late 1990s, \"supply-chain management\" (SCM) rose to prominence, and operations managers began to use it in their titles with increasing regularity.\nOther commonly accepted definitions of supply-chain management include:\nA supply chain, as opposed to supply-chain management, is a set of organizations directly linked by one or more upstream and downstream flows of products, services, finances, or information from a source to a customer. Supply-chain management is the management of such a chain.\nSupply chain visibility, in its origins, was concerned with knowledge of the location/production stage and expected delivery date of incoming products and materials, so that production could be planned, but the development of the term has enabled it to be used to plan orders using knowledge of potential supplies, and to track post-production processes as far as delivery to customers.\nSupply-chain-management software includes tools or modules used to execute supply chain transactions, manage supplier relationships, and control associated business processes. The overall goal of the software is to improve supply chain performance by monitoring a company's supply chain network from end-to-end (suppliers, transporters, returns, warehouses, retailers, manufacturers, and customers).\nIn some cases, a supply chain includes the collection of goods after consumer use for recycling or the reverse logistics processes for returning faulty or unwanted products back to producers up the value chain.\nFunctions.\nSupply-chain management is a cross-functional approach that includes managing the movement of raw materials into an organization, certain aspects of the internal processing of materials into finished goods, and the movement of finished goods out of the organization and toward the end consumer. As organizations strive to focus on core competencies and become more flexible, they reduce ownership of raw materials sources and distribution channels. These functions are increasingly being outsourced to other firms that can perform the activities better or more cost effectively. The effect is to increase the number of organizations involved in satisfying customer demand, while reducing managerial control of daily logistics operations. Less control and more supply-chain partners lead to the creation of the concept of supply-chain management. The purpose of supply-chain management is to improve trust and collaboration among supply-chain partners, thus improving inventory visibility and the velocity of inventory movement. In this section, we have to communicate with all the vendors and suppliers, make some comparisons, and after that, we have to place the order.\nImportance.\nOrganizations increasingly find that they must rely on effective supply chains, or networks, to compete in the global market and networked economy. In Peter Drucker's (1998) new management paradigms, this concept of business relationships extends beyond traditional enterprise boundaries and seeks to organize entire business processes throughout a value chain of multiple companies.\nIn recent decades, globalization, outsourcing, and information technology have enabled many organizations, such as Dell and Hewlett-Packard, to successfully operate collaborative supply networks in which each specialized business partner focuses on only a few key strategic activities. This inter-organizational supply network can be acknowledged as a new form of organization. However, with the complicated interactions among the players, the network structure fits neither \"market\" nor \"hierarchy\" categories. It is not clear what kind of performance impacts different supply-network structures could have on firms, and little is known about the coordination conditions and trade-offs that may exist among the players. From a systems perspective, a complex network structure can be decomposed into individual component firms. Traditionally, companies in a supply network concentrate on the inputs and outputs of the processes, with little concern for the internal management working of other individual players. Therefore, the choice of an internal management control structure is known to impact local firm performance.\nIn the 21st century, changes in the business environment have contributed to the development of supply-chain networks. First, as an outcome of globalization and the proliferation of multinational companies, joint ventures, strategic alliances, and business partnerships, significant success factors were identified, complementing the earlier \"just-in-time\", lean manufacturing, and agile manufacturing practices. Second, technological changes, particularly the dramatic fall in communication costs (a significant component of transaction costs), have led to changes in coordination among the members of the supply chain network.\nMany researchers have recognized supply network structures as a new organizational form, using terms such as \"Keiretsu\", \"Extended Enterprise\", \"Virtual Corporation\", \"Global Production Network\", and \"Next Generation Manufacturing System\". In general, such a structure can be defined as \"a group of semi-independent organizations, each with their capabilities, which collaborate in ever-changing constellations to serve one or more markets in order to achieve some business goal specific to that collaboration\".\nThe importance of supply chain management proved crucial in the 2019-2020 fight against the coronavirus (COVID-19) pandemic that swept across the world. During the pandemic period, governments in countries which had in place effective domestic supply chain management had enough medical supplies to support their needs and enough to donate their surplus to front-line health workers in other jurisdictions. The devastating COVID-19 crisis in US has turned many sectors of the local economy upside down, including the country's storied logistics industry. Some organizations were able to quickly develop foreign supply chains in order to import much needed medical supplies.\nSupply-chain management is also important for organizational learning. Firms with geographically more extensive supply chains connecting diverse trading cliques tend to become more innovative and productive.\nThe security-management system for supply chains is described in ISO/IEC 28000 and ISO/IEC 28001 and related standards published jointly by the ISO and the IEC. Supply-Chain Management draws heavily from the areas of operations management, logistics, procurement, and information technology, and strives for an integrated approach.\nSupply chain resilience.\nAn important element of SCM is supply chain resilience, defined as \"the capacity of a supply chain to persist, adapt, or transform in the face of change\". For a long time, the interpretation of resilience in the sense of engineering resilience (= robustness) prevailed in supply chain management, leading to the notion of \"persistence\". A popular implementation of this idea is given by measuring the \"time-to-survive\" and the \"time-to-recover\" of the supply chain, allowing to identify weak points in the system.\nMore recently, the interpretations of resilience in the sense of ecological resilience and social–ecological resilience have led to the notions of \"adaptation\" and \"transformation\", respectively. A supply chain is thus interpreted as a social-ecological system that – similar to an ecosystem (e.g. forest) – is able to constantly adapt to external environmental conditions and – through the presence of social actors and their ability to foresight – also to transform itself into a fundamentally new system. This leads to a panarchical interpretation of a supply chain, embedding it into a system of systems, allowing to analyze the interactions of the supply chain with systems that operate at other levels (e.g. society, political economy, planet Earth).\nFor example, these three components of resilience can be discussed for the 2021 Suez Canal obstruction, when a ship blocked the canal for several days. Persistence means to \"bounce back\"; in our example it is about removing the ship as quickly as possible to allow \"normal\" operations. Adaptation means to accept that the system has reached a \"new normal\" state and to act accordingly; here, this can be implemented by redirecting ships around the African cape or use alternative modes of transport. Finally, transformation means to question the assumptions of globalization, outsourcing and linear supply chains and to envision alternatives; in this example this could lead to local and circular supply chains that do not need global transportation routes any longer.\nHistorical developments.\nSix major movements can be observed in the evolution of supply-chain management studies: creation, integration, globalization, specialization phases one and two, and SCM 2.0.\nCreation era.\nThe term \"supply chain management\" was first coined by Keith Oliver in 1982. However, the concept of a supply chain in management was of great importance long before, in the early 20th century, especially with the creation of the assembly line. The characteristics of this era of supply-chain management include the need for large-scale changes, re-engineering, downsizing driven by cost reduction programs, and widespread attention to Japanese management practices. However, the term became widely adopted after the publication of the seminal book \"Introduction to Supply Chain Management\" in 1999 by Robert B. Handfield and Ernest L. Nichols, Jr., which published over 25,000 copies and was translated into Japanese, Korean, Chinese, and Russian.\nIntegration era.\nThis era of supply-chain-management studies was highlighted with the development of electronic data interchange (EDI) systems in the 1960s and developed through the 1990s by the introduction of enterprise resource planning (ERP) systems. This era has continued to develop into the 21st century with the expansion of Internet-based collaborative systems. This era of supply-chain evolution is characterized by both increasing value-added and reducing costs through integration.\nA supply chain can be classified as a stage 1, 2, or 3 network. In stage 1–type supply chain, systems such as production, storage, distribution, and material control are not linked and are independent of each other. In a stage 2 supply chain, these are integrated under one plan, and enterprise resource planning (ERP) is enabled. A stage 3 supply chain is one that achieves vertical integration with upstream suppliers and downstream customers. An example of this kind of supply chain is Tesco.\nGlobalization era.\nIt is the third movement of supply-chain-management development, the globalization era, can be characterized by the attention given to global systems of supplier relationships and the expansion of supply chains beyond national boundaries and into other continents. Although the use of global sources in organizations' supply chains can be traced back several decades (e.g., in the oil industry), it was not until the late 1980s that a considerable number of organizations started to integrate global sources into their core business. This era is characterized by the globalization of supply-chain management in organizations with the goal of increasing their competitive advantage, adding value, and reducing costs through global sourcing.\nSpecialization era (phase I): outsourced manufacturing and distribution.\nIn the 1990s, companies began to focus on \"core competencies\" and specialization. They abandoned vertical integration, sold off non-core operations, and outsourced those functions to other companies. This changed management requirements, as the supply chain extended beyond the company walls and management was distributed across specialized supply-chain partnerships.\nThis transition also refocused the fundamental perspectives of each organization. Original equipment manufacturers (OEMs) became brand owners that required visibility deep into their supply base. They had to control the entire supply chain from above, instead of from within. Contract manufacturers had to manage bills of material with different part-numbering schemes from multiple OEMs and support customer requests for work-in-process visibility and vendor-managed inventory (VMI).\nThe specialization model creates manufacturing and distribution networks composed of several individual supply chains specific to producers, suppliers, and customers that work together to design, manufacture, distribute, market, sell, and service a product. This set of partners may change according to a given market, region, or channel, resulting in a proliferation of trading partner environments, each with its own unique characteristics and demands.\nSpecialization era (phase II): supply-chain management as a service.\nSpecialization within the supply chain began in the 1980s with the inception of transportation brokerages, warehouse management (storage and inventory), and non-asset-based carriers, and has matured beyond transportation and logistics into aspects of supply planning, collaboration, execution, and performance management.\nMarket forces sometimes demand rapid changes from suppliers, logistics providers, locations, or customers in their role as components of supply-chain networks. This variability has significant effects on supply-chain infrastructure, from the foundation layers of establishing and managing electronic communication between trading partners to more complex requirements such as the configuration of processes and workflows that are essential to the management of the network itself.\nSupply-chain specialization enables companies to improve their overall competencies in the same way that outsourced manufacturing and distribution has done; it allows them to focus on their core competencies and assemble networks of specific, best-in-class partners to contribute to the overall value chain itself, thereby increasing overall performance and efficiency. The ability to quickly obtain and deploy this domain-specific supply-chain expertise without developing and maintaining an entirely unique and complex competency in house is a leading reason why supply-chain specialization is gaining popularity.\nOutsourced technology hosting for supply-chain solutions debuted in the late 1990s and has taken root primarily in transportation and collaboration categories. This has progressed from the application service provider (ASP) model from roughly 1998 through 2003 to the on-demand model from approximately 2003 through 2006, to the software as a service (SaaS) model currently in focus today.\nSupply-chain management 2.0 (SCM 2.0).\nBuilding on globalization and specialization, the term \"SCM 2.0\" has been coined to describe both changes within supply chains themselves as well as the evolution of processes, methods, and tools to manage them in this new \"era\". The growing popularity of collaborative platforms is highlighted by the rise of TradeCard's supply-chain-collaboration platform, which connects multiple buyers and suppliers with financial institutions, enabling them to conduct automated supply-chain finance transactions.\nWeb 2.0 is a trend in the use of the World Wide Web that is meant to increase creativity, information sharing, and collaboration among users. At its core, the common attribute of Web 2.0 is to help navigate the vast information available on the Web in order to find what is being bought. It is the notion of a usable pathway. SCM 2.0 replicates this notion in supply chain operations. It is the pathway to SCM results, a combination of processes, methodologies, tools, and delivery options to guide companies to their results quickly as the complexity and speed of the supply-chain increase due to global competition; rapid price fluctuations; changing oil prices; short product life cycles; expanded specialization; near-, far-, and off-shoring; and talent scarcity. The supply chain management provider not only list the services for users to access, but also other relevant services such as monitor the warehouse and logistics.\nIncreasing volatility has characterised supply chains since about 2000. Douglass in 2010 referred to an SCM management style known as \"extreme supply chain management\", which:\nBusiness-process integration.\nSuccessful SCM requires a change from managing individual functions to integrating activities into key supply-chain processes. In an example scenario, a purchasing department places orders as its requirements become known. The marketing department, responding to customer demand, communicates with several distributors and retailers as it attempts to determine ways to satisfy this demand. Information shared between supply-chain partners can only be fully leveraged through business process integration, e.g., using Electronic data interchange.\nSupply-chain business-process integration involves collaborative work between buyers and suppliers, joint product development, common systems, and shared information. According to Lambert and Cooper (2000), operating an integrated supply chain requires a continuous information flow. However, in many companies, management has concluded that optimizing product flows cannot be accomplished without implementing a process approach. The key supply-chain processes as stated by Lambert (2004) are:\nMuch has been written about demand management. Best-in-class companies have similar characteristics, which include the following:\nOne could suggest other critical supply business processes that combine these processes stated by Lambert, such as:\nIntegration of suppliers into the new product development process was shown to have a major impact on product target cost, quality, delivery, and market share. Tapping into suppliers as a source of innovation requires an extensive process characterized by development of technology sharing, but also involves managing intellectual property issues.\nTheories.\nThere are gaps in the literature on supply-chain management studies at present. A few authors, such as Halldorsson et al., Ketchen and Hult (2006), and Lavassani et al. (2009), have tried to provide theoretical foundations for different areas related to supply chain by employing organizational theories, which may include the following:\nHowever, the unit of analysis of most of these theories is not the supply chain but rather another system, such as the firm or the supplier-buyer relationship. Among the few exceptions is the relational view, which outlines a theory for considering dyads and networks of firms as a key unit of analysis for explaining superior individual firm performance (Dyer and Singh, 1998).\nOrganization and governance.\nThe management of supply chains involve a number of specific challenges regarding the organization of relationships among the different partners along the value chain. Formal and informal governance mechanisms are central elements in the management of supply chain. Particular combinations of governance mechanisms may impact the relational dynamics within the supply chain. The need for interdisciplinarity in SCM research has been pointed out by academics in the field.\nSupply chain centroids.\nIn the study of supply-chain management, the concept of centroids has become a useful economic consideration. In mathematics and physics, a centroid is the arithmetic mean position of all the points in a plane figure. For supply chain management, a centroid is a location with a high proportion of a country's population and a high proportion of its manufacturing, generally within . In the US, two major supply chain centroids have been defined, one near Dayton, Ohio, and a second near Riverside, California.\nThe centroid near Dayton is particularly important because it is closest to the population center of the US and Canada. Dayton is within 500 miles of 60% of the US population and manufacturing capacity, as well as 60% of Canada's population. The region includes the interchange between I-70 and I-75, one of the busiest in the nation, with 154,000 vehicles passing through per day, of which 30–35% are trucks hauling goods. In addition, the I-75 corridor is home to the busiest north–south rail route east of the Mississippi River.\nA supply chain is the network of all the individuals, organizations, resources, activities and technology involved in the creation and sale of a product. A supply chain encompasses everything from the delivery of source materials from the supplier to the manufacturer through to its eventual delivery to the end user. The supply chain segment involved with getting the finished product from the manufacturer to the consumer is known as the distribution channel.\nWal-Mart strategic sourcing approaches.\nIn 2010, Wal-Mart announced a big change in its sourcing strategy. Initially, Wal-Mart relied on intermediaries in the sourcing process. It bought only 20% of its stock directly, but the rest were bought through the intermediaries. Therefore, the company came to realize that the presence of many intermediaries in the product sourcing was actually increasing the costs in the supply chain. To cut these costs, Wal-Mart decided to do away with intermediaries in the supply chain and started direct sourcing of its goods from the suppliers. Eduardo Castro-Wright, the then Vice President of Wal-Mart, set an ambitious goal of buying 80% of all Wal-Mart goods directly from the suppliers. Walmart started purchasing fruits and vegetables on a global scale, where it interacted directly with the suppliers of these goods. The company later engaged the suppliers of other goods, such as cloth and home electronics appliances, directly and eliminated the importing agents. The purchaser, in this case Wal-Mart, can easily direct the suppliers on how to manufacture certain products so that they can be acceptable to the consumers. Thus, Wal-Mart, through direct sourcing, manages to get the exact product quality as it expects, since it engages the suppliers in the producing of these products, hence quality consistency. Using agents in the sourcing process in most cases lead to inconsistency in the quality of the products, since the agent's source the products from different manufacturers that have varying qualities.\nWal-Mart managed to source directly 80% profit its stock; this has greatly eliminated the intermediaries and cut down the costs between 5-15%, as markups that are introduced by these middlemen in the supply chain are cut. This saves approximately $4–15 billion. This strategy of direct sourcing not only helped Wal-Mart in reducing the costs in the supply chain but also helped in the improvement of supply chain activities through boosting efficiency throughout the entire process. In other words, direct sourcing reduced the time that takes the company to source and stocks the products in its stock. The presence of the intermediaries elongated the time in the process of procurement, which sometimes led to delays in the supply of the commodities in the stores, thus, customers finding empty shelves. Wal-Mart adopted this strategy of sourcing through centralizing the entire process of procurement and sourcing by setting up four global merchandising points for general goods and clothing. The company instructed all the suppliers to bring their products to these central points that are located in different markets. The procurement team assesses the quality brought by the suppliers, buys the goods, and distributes them to various regional markets. The procurement and sourcing at centralized places helped the company to consolidate the suppliers.\nThe company has established four centralized points, including an office in Mexico City and Canada. Just a mere piloting test on combining the purchase of fresh apples across the United States, Mexico, and Canada led to the savings of about 10%. As a result, the company intended to increase centralization of its procurement in North America for all its fresh fruits and vegetables. Thus, centralization of the procurement process to various points where the suppliers would be meeting with the procurement team is the latest strategy which the company is implementing, and signs show that this strategy is going to cut costs and also improve the efficiency of the procurement process.\nStrategic vendor partnerships is another strategy the company is using in the sourcing process. Wal-Mart realized that in order for it to ensure consistency in the quality of the products it offers to the consumers and also maintain a steady supply of goods in its stores at a lower cost, it had to create strategic vendor partnerships with the suppliers. Wal-Mart identified and selected the suppliers who met its demand and at the same time offered it the best prices for the goods. It then made a strategic relationship with these vendors by offering and assuring the long-term and high volume of purchases in exchange for the lowest possible prices. Thus, the company has managed to source its products from same suppliers as bulks, but at lower prices. This enables the company to offer competitive prices for its products in its stores, hence, maintaining a competitive advantage over its competitors whose goods are a more expensive in comparison.\nAnother sourcing strategy Wal-Mart uses is implementing efficient communication relationships with the vendor networks; this is necessary to improve the material flow. The company has all the contacts with the suppliers whom they communicate regularly and make dates on when the goods would be needed, so that the suppliers get ready to deliver the goods in time. The efficient communication between the company's procurement team and the inventory management team enables the company to source goods and fill its shelves on time, without causing delays and empty shelves. In other words, the company realized that in ensuring a steady flow of the goods into the store, the suppliers have to be informed early enough, so that they can act accordingly to avoid delays in the delivery of goods. Thus, efficient communication is another tool which Wal-Mart is using to make the supply chain be more efficient and to cut costs.\nCross-docking is another strategy that Wal-Mart is using to cut costs in its supply chain. Cross-docking is the process of transferring goods directly from inbound trucks to outbound trucks. When the trucks from the suppliers arrive at the distribution centers, most of the trucks are not offloaded to keep the goods in the distribution centers or warehouses; they are transferred directly to another truck designated to deliver goods to specific retail stores for sale. Cross-docking helps in saving the storage costs. Initially, the company was incurring considerable costs of storing the goods from the suppliers in its warehouses and the distributions centers to await the distribution trucks to the retail stores in various regions.\nTax-efficient supply-chain management.\nTax-efficient supply-chain management is a business model that considers the effect of tax in the design and implementation of supply-chain management. As the consequence of globalization, cross-national businesses pay different tax rates in different countries. Due to these differences, they may legally optimize their supply chain and increase profits based on tax efficiency.\nSustainability and social responsibility in supply chains.\nSupply chain networks are integral to an economy, but the health of chains is dependent on the well-being of the environment and society. Supply-chain sustainability is a business issue affecting an organization's supply chain or logistics network, and is frequently quantified by comparison with SECH ratings, which use a triple bottom line incorporating economic, social, and environmental aspects. While SECH ratings are defined as social, ethical, cultural, and health footprints, the more commonly used ESG moniker stands for Environment, Social and Governance. Consumers have become more aware of the environmental impact of their purchases and companies' ratings and, along with non-governmental organizations (NGOs), are setting the agenda, and beginning to push, for transitions to more sustainable approaches such as organically grown foods, anti-sweatshop labor codes, and locally produced goods that support independent and small businesses. Because supply chains may account for over 75% of a company's carbon footprint, many organizations are exploring ways to reduce this and thus improve their profile.\nFor example, in July 2009, Wal-Mart announced its intentions to create a global sustainability index that would rate products according to the environmental and social impacts of their manufacturing and distribution. The index is intended to create environmental accountability in Wal-Mart's supply chain and to provide motivation and infrastructure for other retail companies to do the same.\nIt has been reported that companies are increasingly taking environmental performance into account when selecting suppliers. A 2011 survey by the Carbon Trust found that 50% of multinationals expect to select their suppliers based upon carbon performance in the future and 29% of suppliers could lose their places on 'green supply chains' if they do not have adequate performance records on carbon.\nIn addition to environmental concerns, increased globalization within global supply chains challenges human rights and worker exploitation risks within multinational corporations including forced labor and modern slavery. Textiles, agriculture, and manufacturing are some of the industries with significant labor exploitation risks. There are many different methods governments, corporations, and NGOs use to prevent labor exploitation, including corporate social responsibility, export controls, import bans, and monitoring labor standards.\nThe US Dodd–Frank Wall Street Reform and Consumer Protection Act, signed into law by President Obama in July 2010, contained a supply chain sustainability provision in the form of the Conflict Minerals law. This law requires SEC-regulated companies to conduct third party audits of their supply chains in order to determine whether any tin, tantalum, tungsten, or gold (together referred to as \"conflict minerals\") is mined or sourced from the Democratic Republic of the Congo, and create a report (available to the general public and SEC) detailing the due diligence efforts taken and the results of the audit. The chain of suppliers and vendors to these reporting companies will be expected to provide appropriate supporting information.\nIncidents like the 2013 Savar building collapse with more than 1,100 victims have led to widespread discussions about corporate social responsibility across global supply chains. Wieland and Handfield (2013) suggest that companies need to audit products and suppliers and that supplier auditing needs to go beyond direct relationships with first-tier suppliers. They also demonstrate that visibility needs to be improved if supply cannot be directly controlled and that smart and electronic technologies play a key role to improve visibility. Finally, they highlight that collaboration with local partners, across the industry and with universities is crucial to successfully managing social responsibility in supply chains.\nCircular supply-chain management.\nCircular Supply-Chain Management (CSCM) is \"the configuration and coordination of the organizational functions marketing, sales, R&D, production, logistics, IT, finance, and customer service within and across business units and organizations to close, slow, intensify, narrow, and dematerialise material and energy loops to minimize resource input into and waste and emission leakage out of the system, improve its operative effectiveness and efficiency and generate competitive advantages\". By reducing resource input and waste leakage along the supply chain and configure it to enable the recirculation of resources at different stages of the product or service lifecycle, potential economic and environmental benefits can be achieved. These comprise e.g. a decrease in material and waste management cost and reduced emissions and resource consumption.\nComponents.\nManagement components.\nSCM components are the third element of the four-square circulation framework. The level of integration and management of a business process link is a function of the number and level of components added to the link. Consequently, adding more management components or increasing the level of each component can increase the level of integration of the business process link.\nLiterature on business process reengineering, buyer-supplier relationships, and SCM suggests various possible components that should receive managerial attention when managing supply relationships. Lambert and Cooper (2000) identified the following components:\nHowever, a more careful examination of the existing literature leads to a more comprehensive understanding of what should be the key critical supply chain components, or \"branches\" of the previously identified supply chain business processes—that is, what kind of relationship the components may have that are related to suppliers and customers. Bowersox and Closs (1996) state that the emphasis on cooperation represents the synergism leading to the highest level of joint achievement. A primary-level channel participant is a business that is willing to participate in responsibility for inventory ownership or assume other financial risks, thus including primary level components. A secondary-level participant (specialized) is a business that participates in channel relationships by performing essential services for primary participants, including secondary level components, which support primary participants. Third-level channel participants and components that support primary-level channel participants and are the fundamental branches of secondary-level components may also be included.\nConsequently, Lambert and Cooper's framework of supply chain components does not lead to any conclusion about what are the primary- or secondary-level (specialized) supply chain components —that is, which supply chain components should be viewed as primary or secondary, how these components should be structured in order to achieve a more comprehensive supply chain structure, and how to examine the supply chain as an integrative one.\nPower in supply chain management.\nAndrew Cox, Joe Sanderson and Glyn Watson argue that the power resources of buyers and suppliers should be analyzed in order to understand how a supply chain relationship operates. In some cases, a purchasing firm may exercise more power over its suppliers, in other cases, suppliers may have more power; yet again there will be cases where buyers and suppliers may be interdependent or may have no real power over each other. Cox, Sanderson and Watson have written extensively on the operation of power regimes within a supply chain context. Other studies of power in supply chain relationships have looked at drivers impacting on the potential integration of supply chains. A study by Michael Maloni and W. C. Benton in 1998 looked at whether potential asymmetries in inter-firm power within a supply chain could prevent the implementation of effective supply chain execution. Maloni and Benton note that until their research, \"little power research\" had been presented in the supply chain literature. Using French and Raven's typology of the sources of power in the context of the automotive industry, they aimed to analyse the effects of distinct power strategies on relationships between buyers and sellers, and upon supply chain performance and satisfaction. Their findings showed that:\nThey concluded that \"prudent use of power\" can be beneficial for both the power source and the power target.\nReverse supply chain.\nReverse logistics is the process of managing the return of goods and may be considered as an aspect of \"aftermarket customer services\". Any time money is taken from a company's warranty reserve or service logistics budget, one can speak of a reverse logistics operation. Reverse logistics also includes the process of managing the return of goods from store, which the returned goods are sent back to warehouse and after that either warehouse scrap the goods or send them back to supplier for replacement depending on the warranty of the merchandise.\nDigitizing supply chains.\nConsultancies and media expect the performance efficacy of digitizing supply chains to be high. Additive manufacturing and blockchain technology have emerged as the two technologies with some of the highest economic relevance.\nSystems and value.\nSupply chain systems configure value for those that organize the networks. Value is the additional revenue over and above the costs of building the network. Co-creating value and sharing the benefits appropriately to encourage effective participation is a key challenge for any supply system. Tony Hines defines value as follows: \"Ultimately it is the customer who pays the price for service delivered that confirms value and not the producer who simply adds cost until that point\".\nGlobal applications.\nGlobal supply chains pose challenges regarding both quantity and value. Supply and value chain trends include:\nThese trends have many benefits for manufacturers because they make possible larger lot sizes, lower taxes, and better environments (e.g., culture, infrastructure, special tax zones, or sophisticated OEM) for their products. There are many additional challenges when the scope of supply chains is global. This is because with a supply chain of a larger scope, the lead time is much longer, and because there are more issues involved, such as multiple currencies, policies, and laws. The consequent problems include different currencies and valuations in different countries, different tax laws, different trading protocols, vulnerability to natural disasters and cyber threats, and lack of transparency of cost and profit.\nRoles and responsibilities.\nSupply chain professionals play major roles in the design and management of supply chains. In the design of supply chains, they help determine whether a product or service is provided by the firm itself (insourcing) or by another firm elsewhere (outsourcing). In the management of supply chains, supply chain professionals coordinate production among multiple providers, ensuring that production and transport of goods happen with minimal quality control or inventory problems. One goal of a well-designed and maintained supply chain for a product is to successfully build the product at minimal cost. Such a supply chain could be considered a competitive advantage for a firm.\nBeyond design and maintenance of a supply chain itself, supply chain professionals participate in aspects of business that have a bearing on supply chains, such as sales forecasting, quality management, strategy development, customer service, and systems analysis. Production of a good may evolve over time, rendering an existing supply chain design obsolete. Supply chain professionals need to be aware of changes in production and business climate that affect supply chains and create alternative supply chains as the need arises.\nIn a research project undertaken by Michigan State University's Broad College of Business, with input from 50 participating organizations, the main issues of concern to supply chain managers were identified as capacity/resource availability, talent (recruitment), complexity, threats/challenges (supply chain risks), compliance and cost/purchasing issues. Keeping up with frequent changes in regulation was identified as a particular concern. Complexity within supply chains has also been highlighted in \"Supply Chain Digest\" and by Gartner as a perennial challenge.\nSupply chain consultants may provide expert knowledge in order to assess the productivity of a supply-chain and, ideally, to enhance its productivity. Supply chain consulting involves the transfer of knowledge on how to exploit existing assets through improved coordination and can hence be a source of competitive advantage: the role of the consultant is to help management by adding value to the whole process through the various sectors from the ordering of the raw materials to the final product. In this regard, firms may either build internal teams of consultants to tackle the issue or engage external ones: companies choose between these two approaches taking into consideration various factors.\nThe use of external consultants is a common practice among companies. The whole consulting process generally involves the analysis of the entire supply-chain process, including the countermeasures or correctives to take to achieve a better overall performance.\nSkills and competencies.\nSupply chain professionals need to have knowledge of managing supply chain functions such as transportation, warehousing, inventory management, and production planning. In the past, supply chain professionals emphasized logistics skills, such as knowledge of shipping routes, familiarity with warehousing equipment and distribution center locations and footprints, and a solid grasp of freight rates and fuel costs. More recently, supply-chain management extends to logistical support across firms and management of global supply chains. Supply chain professionals need to have an understanding of business continuity basics and strategies, and Tramarico \"et al\" noted that several processes from other disciplinary theories, including the resource-based view, supply chain design and interorganizational relationships are integral to a mature understanding of supply chain management.\nCertification.\nIndividuals working in supply-chain management can attain professional certification by passing an exam developed by a third party certification organization. The purpose of certification is to guarantee a certain level of expertise in the field. The knowledge needed to pass a certification exam may be gained from several sources. Some knowledge may come from college courses, but most of it is acquired from a mix of on-the-job learning experiences, attending industry events, learning best practices with their peers, and reading books and articles in the field. Certification organizations may provide certification workshops tailored to their exams.\nUniversity rankings.\nThe following North American universities rank high in their master's education in the SCM World University 100 ranking, which was published in 2017 and which is based on the opinions of supply chain managers: Michigan State University, Penn State University, University of Tennessee, Massachusetts Institute of Technology, Arizona State University, University of Texas at Austin and Western Michigan University. In the same ranking, the following European universities rank high: Cranfield School of Management, Vlerick Business School, INSEAD, Cambridge University, Eindhoven University of Technology, London Business School and Copenhagen Business School. \nThe following universities rank high in the 2016 Eduniversal Best Masters ranking for supply chain and logistics: Massachusetts Institute of Technology, KEDGE Business School, Purdue University, Rotterdam School of Management, Pontificia Universidad Catolica del Peru, Universidade Nova de Lisboa, Vienna University of Economics and Business and Copenhagen Business School.\nOrganizations.\nA number of organizations provide certification in supply chain management, such as the Council of Supply Chain Management Professionals (CSCMP), IIPMR (International Institute for Procurement and Market Research), APICS (the Association for Operations Management), ISCEA (International Supply Chain Education Alliance) and IoSCM (Institute of Supply Chain Management). APICS' certification is called \"Certified Supply Chain Professional\", or CSCP, and ISCEA's certification is called the \"Certified Supply Chain Manager\" (CSCM), CISCM (Chartered Institute of Supply Chain Management) awards certificate as \"Chartered Supply Chain Management Professional\" (CSCMP). Another, the Institute for Supply Management, is developing one called the \"Certified Professional in Supply Management\" (CPSM) focused on the procurement and sourcing areas of supply-chain management. The Supply Chain Management Association (SCMA) is the main certifying body for Canada with the designations having global reciprocity. The designation Supply Chain Management Professional (SCMP) is the title of the supply chain leadership designation.\nTopics addressed by selected professional supply chain certification programmes.\nThe following table compares topics addressed by selected professional supply chain certification programmes.", "Engineering,_Manufacturing": 0.910722971, "qwen": "Yes"}
{"id": "8822417", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=8822417", "title": "Flatbed digital printer", "text": "Flatbed digital printers, also known as flatbed printers or flatbed UV printers, are printers characterized by a flat surface upon which a material is placed to be printed on. Flatbed printers are capable of printing on a wide variety of materials such as photographic paper, film, cloth, plastic, pvc, acrylic, glass, ceramic, metal, wood, leather, etc.). Flatbed digital printers usually use UV curable inks made of acrylic monomers that are then exposed to strong UV-light to cure, or polymerize them. This process allows for printing on a wide variety of surfaces such as wood or canvas, carpet, tile, and even glass. The adjustable printing bed makes it possible to print on surfaces ranging in thickness from a sheet of paper often up to as much as several inches. Typically used for commercial applications (retail and event signage), flatbed printing is often a substitute for screen-printing. Since no printing plates or silkscreens must be produced, digital printing technology allows shorter runs of signs to be produced economically. Many of the high-end flatbed printers allow for roll-feed, allowing for unattended printing.\nEnvironmentally, flatbed digital printing is based on a more sustainable system than its commercial predecessor of solvent printing as it produces fewer waste cartridges and less indoor air pollution. The resolution of flatbed printers range from 72 DPI (dots per inch) to about 2400 DPI. One of the advantages of a flatbed printer is its versatility of printable materials although this is limited to only flat materials and occupies a lot of surface area.\n\"Hybrid\" Flatbed Digital Printers.\nAlthough most flatbed printers are limited to printing on flat some are capable of printing of cylindrical objects, such as bottles and cans, using rotary attachments that position the object and rotate it while the printhead applies ink. Flatbed printers have sometimes been used to print on small spherical objects such as ping pong balls, however, the print resolution tends to decrease around the edges of the printed image due to the inkjets firing ink onto an inclined and further away surface.\nFlatbed printers can sometimes execute multiple passes on a surface to achieve an 3D embossing effect. This is either done with colored inks or a clear varnish which is used to create glossy finishes or highlights on the print.\n\"Hybrid\" UV printers may also refer to printers capable of printing of a flatbed surface as well as roll-to-roll, which enables the use of flexible substrates stored in rolls.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "39701014", "revid": "7583140", "url": "https://en.wikipedia.org/wiki?curid=39701014", "title": "Cast urethanes", "text": "Cast Urethanes are similar to injection molding. During the process of injection molding, a hard tool is created. The hard tool, made of an A side and a B side, forms a void within and that void is injected with plastics ranging in material property, durability, and consistency. Plastic cups, dishware, and toys are most commonly made using the process of injection molding because they are common consumer items that need to be produced on a mass scale, and injection molding (once the hard tool has been created) is designed for mass production.\nCasting urethanes is similar in that polyurethanes are injected into a tool. But with cast urethanes, the tool is a soft tool, typically made with a type of silicone mold. The mold is created via a master pattern. Master patterns for cast urethanes can be created with CNC machining (which is a common process for injection molding) but cast urethane master patterns are often created with additive manufacturing (or 3D Printing) and the reasons for this vary.\nCreating a cast urethane master pattern is different from the steps involved in creating hard tooling for injection molding. Hard tools for injection molding are going to be subjected to a lot of stress and heat during the injection process. They will see runs of thousands of parts per day. The care that goes into a hard tool involves intense machine programming which costs thousands of dollars alone. The price for hard tooling is balanced by the mass production the tooling brings, which is where cast urethanes begin to differ. Cast urethanes are suited for smaller runs of parts and prototyping. Because the cost for soft tooling is lower, down in the hundreds rather than hundreds of thousands, cast urethanes are excellent resources for creators still testing product design, for one-off products, or for testing market and consumer response to a new product.\nMaster Patterns.\nCast urethane master patterns can be produced using machining, additive manufacturing—even an already existing product. The master pattern is used to create an A side and a B side for a mold. The pattern is used to form a void within a mold. The mold material is one that easily picks up surface detail (such as silicones) because the mold will be responsible for reflecting the surface of the product.\nApplications.\nThere are many types of cast urethane applications including:\nProcess.\nCast urethane starts as a liquid that can be dispensed into a mold, post cured in ovens and where required, secondary machining operations can be added. Cast thermoset urethanes have better physical properties than most injection or extruded thermoplastics. Dispensing liquid urethane into open molds or compression tools makes it possible to cast just about any configuration from affordable tooling.\nSteps include first printing a master pattern for an accurate silicone mold, which is then encased in liquid silicone. After the mold cures, it is cut into distinct sections and the pattern is removed. The cavity formed is used for casting the end product. The cavity or void is filled with a material, which will cure and be removed from the tool.\nIndustries.\nThe types of industries that utilize cast urethane include:", "Engineering,_Manufacturing": 0.9999893904, "qwen": "Yes"}
{"id": "39727528", "revid": "1135707515", "url": "https://en.wikipedia.org/wiki?curid=39727528", "title": "Powertech Technology", "text": "Powertech Technology Inc. (PTI  6239. TW) is a Taiwanese semiconductor assembly, packaging and testing company.\nIn 2010 the company entered a strategic alliance with Japan's Elpida Memory and Taiwan's chip foundry United Microelectronics Corporation to develop advanced semiconductor packaging technology. \nThe company is purported to be manufacturing Apple Inc.'s Apple S1 chip for their recently announced Apple Watch. ", "Engineering,_Manufacturing": 1.0000050068, "qwen": "Yes"}
{"id": "30699716", "revid": "33974892", "url": "https://en.wikipedia.org/wiki?curid=30699716", "title": "Pay on production", "text": "Pay on production (PoP) is a special build-operate-transfer (BOT) model, where payment is made to a supplier by the original equipment manufacturer (OEM) per piece produced on the supplier's own equipment by the OEM's employees.\nDescription.\nMost build-operate-transfer systems work in a way that the final manufacturer (OEM) doesn't invest in the production equipment for parts or components but instead procures these parts from a supplier who organises production on his equipment. An example from vehicle manufacturing might be the assembly of wheels and tyres. The OEM might decide not to invest in a wheel assembly line but instead obtain from a supplier or logistics service provider delivery of these items just in sequence as these are needed at the OEM's assembly line: sometimes five with steel rim followed by four with light-alloy rim and a compact spare tire and so on. This is a longstanding and common methodology where the production and supply of many items and services are outsourced to other providers, typically to obtain better cost, quality and delivery performance than can be achieved in house, and also enable the OEM to better focus on core activities.\nWith PoP one important thing is different. The very equipment on which the OEM produces or assembles the final product, in the OEM factory, is supplied by, but still remains owned by, and is also maintained by, the equipment supplier. But it is still the OEM's personnel who assemble the products on the equipment and facilities. The external equipment supplier is then paid a fixed price for every product item which is assembled or produced on their equipment. The general idea of PoP is similar to using a rented car. The car is always owned and maintained by the car rental company but used or driven by the customer. The customer pays the car rental company for using the car, e.g. per every driven kilometre. However, in the assembly line case the contract is not just for a few days, rather both partners plan to keep the agreement for as long as the product is produced on the equipment, though it can be terminated before this. It means PoP is not therefore so much a production system, more of a financial model.\nThis concept was established by the German Ford Motor Company in Cologne for the Fiesta assembly line in 2002, and was soon recognised as the most productive in the world measured by working hours used to assemble a car. The new Fiesta was started on this line at 2008 and the high productivity remained (i.e. til 2010). This is despite the Cologne factory, because the buildings are 90 years old, is laid out in such a way that many new production developments just can't be introduced. For example, component suppliers can't deliver straight to the assembly line nor is there room for more flexible U shaped assembly areas. Parts have to be delivered to a separate ‘supermarket’ type warehouse where kits of required parts are boxed and made up for use on the lines. For the Cologne factory the main assembly lines and some of the cells, for example where engines are fitted to the body, are owned and maintained by several equipment suppliers.\nHistory and Background.\nWithin the beginning of the 21st century, the Ford Motor Company's goal was to focus and concentrate on designing new cars. There were no surplus funds available for investment in the modern manufacturing equipment needed at the Cologne plant. Indeed, for the equipment suppliers their participation in PoP was the only option available.\nMost of the costs incurred by the OEM in PoP are variable costs such as labour and materials, though there is also in this case an additional variable cost for the equipment for every car produced. The fixed cost of the production equipment is borne the external equipment suppliers. For the OEM it means that PoP allows it to run its own production, but without incurring the high fixed capital cost of the equipment, and of course this cost is absent from any US GAAP balance sheet, not even included as a footnote, nor is it factor in assessment by financial rating agencies. Also with PoP much of the OEM's entrepreneurial risks are passed to the equipment supplier.\nFor the equipment supplier bearing the equipment capital cost can often be a financial problem, because, where these are SME companies, they are not always able to easily obtain sufficient investment capital, nor are they able to receive money from global financial markets. However the assembly lines and cells can't be sold or built without the supplier's permission and, most importantly, the equipment supplier, who has continuous contact with the lines and cells, is much closer to its customers so enabling ongoing CIP (continuous improvement process) both in the equipment maintenance and collaborative future line design improvements. CIP improvements in production stay with the OEM\nBecause the use of the practice by Ford in Cologne was so successful its use and adoption was tried at other Ford assembly plants. Perhaps not unsurprisingly, Ford has not been successful in their attempts to expand this Ford Cologne-based system elsewhere.", "Engineering,_Manufacturing": 0.9999428988, "qwen": "Yes"}
{"id": "17991164", "revid": "41927601", "url": "https://en.wikipedia.org/wiki?curid=17991164", "title": "Quick response manufacturing", "text": "Quick response manufacturing (QRM) is an approach to manufacturing which emphasizes the beneficial effect of reducing internal and external lead times.\nDescription.\nShorter lead times improve quality, reduce cost and eliminate non-value-added waste within the organization while simultaneously increasing the organization's competitiveness and market share by serving customers better and faster.\nThe time-based framework of QRM accommodates strategic variability such as offering custom-engineered products while eliminating dysfunctional variability such as rework and changing due dates. For this reason, companies making products in low or varying volumes have used QRM as an alternative or to complement other strategies such as Lean Manufacturing, Total quality management, Six Sigma or Kaizen. However, the benefits of QRM are still mooted and contested by experts around. Many opposers of QRM criticize its approach being very \"marketing-style\" rather than academic or statistical.\nHistory.\nBackground.\nQRM is rooted in the concept of Time-based competition (TBC) pioneered by Japanese enterprises in the 1980s and first formulated by George Stalk Jr. in his 1988 article entitled \"Time – The Next Source of Competitive Advantage\". Time-based competition is a broad-based competitive strategy emphasizing time as the major factor for achieving and maintaining a sustainable competitive advantage. It seeks to compress the time required to propose, develop, manufacture, market and deliver products.\nQRM advocates a companywide focus on short lead times that include quick response to demand for existing products as well as new product and design changes. This combination has led to the implementation of QRM in many high-mix, low-volume companies.\nSome argue that Quick Response Manufacturing differs from Quick Response (QR) methods used in the apparel industry and the fast fashion market. QRM is a companywide management strategy applicable to a wide variety of businesses, whereas QR primarily stands for a specific business model in a particular industry. However, the important difference to note is that QR was a competitive industry initiative introduced in the US Textile Industry in 1984 as a means of improving efficiencies in manufacturing and supply chain processes and as such was one of the earliest pioneers of putting into practice time-based competition prior to Stalk's seminal article. Thus QR crossed the traditional boundaries of organization and was not limited to a single organizational efficiency improvement such as that advocated by proponents of QRM. In this respect the Textile Industry initiative was innovative and visionary in its application of QR techniques across the supply chain.\nDevelopment.\nThe concept of Quick Response Manufacturing (QRM) was first developed in the late 1980s by Rajan Suri, at the time professor of Industrial and Systems Engineering at the University of Wisconsin-Madison. Combining growing academic research in Time-based Competition (TBC) with his own observations from various lead time reduction projects, Suri conceived QRM as a concept espousing a relentless emphasis on lead time reduction that has a long-term impact on every aspect of the company.\nIn 1993, Suri, along with a few U.S. Midwest companies and academic colleagues at the University of Wisconsin-Madison, launched the Center for Quick Response Manufacturing, a consortium dedicated to the development and implementation of QRM principles in an industry setting. Proposed by Suri, the newly coined term \"Quick Response Manufacturing\" (QRM) signifies the new strategy.\nQRM extends basic principles of time-based competition while including these new aspects:\nSuri's continued research into QRM through industry projects along with enthusiastic responses to various articles on lead time reduction issues led him to develop a comprehensive theory on implementing speed in a manufacturing company, covering all areas in the enterprise. He formulated his theory in the book \"Quick Response Manufacturing: A Companywide Approach to Reducing Lead Times (1998)\", providing a framework for the implementation of QRM in manufacturing companies.\nQRM Strategies and Tools.\nLead time as a management strategy.\nTraditionally, U.S. manufacturing firms have focused on scale and cost management strategies based on the division of labor practices formalized by Frederick Winslow Taylor and pioneered by Henry Ford.\nFrom the time-based perspective of QRM, the high degree of labor specialization and hierarchical department structures at purely cost-based organizations have these negative effects on lead times:\nAll these factors contribute to long lead times, ultimately resulting in waste throughout the enterprise such as excessive forecasting, planning, scheduling, expediting, work in progress (WIP), finished goods costs and obsolescence. These increase the overall costs and lower the organization's competitiveness.\nQRM suggests that an enterprisewide focus on reducing lead times will result in improvements in both quality and cost. Eliminating the time-consuming – and often self-reinforcing – practices described above can lead to large cost savings while improving product quality and customer responsiveness. Hence, on a management level, QRM advocates a mindset change from cost-based to time-based thinking, making short lead times the yardstick for organizational success.\nManufacturing Critical-path Time (MCT).\nQRM's strong focus on lead time reduction requires a comprehensive definition of lead time. To accomplish this, QRM introduces Manufacturing Critical-path Time (MCT). It is based on the standard critical path method; defined as the typical amount of calendar time from when a customer creates an order, until the first piece of that order is delivered to the customer.\nA metric designed to calculate waste and highlight opportunities for improvement, MCT gives an estimate of the time it takes to fulfill an order, quantifying the longest critical-path duration of order-fulfillment activities.\nOrganizational structure.\nQRM requires four fundamental structural changes to transform a company organized around cost-based management strategies to a time-based focus:\nQRM Cell.\nThe main building block of the QRM organization is the QRM cell. Extending the concept of cellular manufacturing, QRM cells are designed around a Focused Target Market Segment (FTMS) – a segment of the market in which shorter product lead times provide the company with maximum benefits. Resources in a cell are dedicated (only to be used for jobs in the cell), collocated (located in close proximity to each other) and multifunctional (cover different functions). QRM cells complete a sequence of operations ensuring that jobs leave the cell completed and do not need to return.\nThe work organization in QRM cells is based on team ownership. Provided with a job and a completion deadline, teams can decide independently on how to complete the job. To ensure quick response to high-variety demand, workers in QRM cells need to go through cross training.\nThe main performance measure for a QRM cell is lead time as defined by MCT. To measure MCT reduction, managers can use the QRM number, a metric designed to show management lead time trends for cells.\nSystem Dynamics.\nIn QRM, the product-focused cell structure has to be complemented by a thorough understanding of system dynamics in order to make better decisions to reduce lead times. Based on principles of system dynamics, QRM identifies high utilization of machines and labor as well as running large batch sizes as major obstacles to lead time reduction.\nCreate spare capacity.\nMany cost-based organizations aim for machines and labor to be utilized at close to 100% of capacity. QRM criticizes this approach as counterproductive to lead time reduction based on queuing theory, which shows that high utilization increases waiting times for products. In order to be able to handle high variability in demand and products, QRM advises companies to operate at 80 percent capacity on critical resources.\nOptimize batch sizes.\nCommon efficiency measures encourage production of parts in large batch sizes. From the QRM perspective, large batch sizes lead to long waiting times, high WIP and inventory, and ultimately long lead times. Long lead times in turn result in multiple forms of waste and increased cost as described above. Thus, QRM encourages enterprise to strive towards batch sizes that minimize lead times.\nEnterprisewide Application.\nQRM emphasizes time-based thinking throughout the organization, creating a unified management strategy for the entire enterprise. Extending beyond traditional efforts to optimize shop floor operations, QRM applies time-based management principles to all other parts of the organization.\nOffice Operations.\nQRM identifies office operations such as quoting, engineering, scheduling and order processing as major contributors to lead times. To achieve short lead times in the office environment, QRM suggests implementing several changes according to the time-based approach described above.\nThe main requirement for reorganizing office operations in QRM is the formation of a Quick Response Office Cell (Q-ROC) around a Focus Target Market Segment (FTMS). In their focus on closed-loop, collocated, multifunctional, cross-trained teams, Q-ROCs are similar to QRM Cells. Q-ROCs, like QRM cells on the shop floor, break down functional departments and can complete jobs through multiple functional steps.\nMaterial Planning.\nQRM criticizes commonly used material planning and scheduling systems such as Material Requirements Planning (MRP), Manufacturing resource planning (MRP II), and Enterprise resource planning (ERP) for not incorporating system dynamics in their analysis and not accounting for the cost of long lead times.\nQRM recommends simplifying existing MRP systems to a Higher Level MRP (HL/MRP) concerned with high-level planning and coordination of material and not with detailed scheduling of operations.\nProduction Control.\nTo coordinate and control flow within the QRM structure of cells and HL/MRP, QRM utilizes POLCA (Paired-cell Overlapping Loops of Cards with Authorization). POLCA is a card-based shop floor control system, designed as the QRM alternative to Kanban.\nPOLCA differs from commonly used Kanban systems in the type of signal it sends to move jobs/material through the shop floor. POLCA constitutes a capacity signal, showing that a cell is ready to work on a new job, whereas Kanban systems rely on inventory signals designed to replenish a certain quantity of parts. For this reason, POLCA works well for low-volume and/or custom products. The first QRM shop floor control system was developed by PROPOS software. PROPOS software was also the first to develop a digital version of the POLCA card system. In March 2018 Rajan Suri published The Practitioner's Guide to POLCA: The Production Control System for High-Mix, Low-Volume and Custom Products] in which Suri describes a practical approach to POLCA to maximize production efficiency, reduce WIP (Work in Process) and prevent bottlenecks from forming. Suri also describes the use of PROPOS QRM software and digital POLCA, illustrated by a case at BOSCH Scharnieren. This Dutch manufacturer produces custom metal hinges and managed to greatly reduce lead times and optimize the production flow in their job shop using QRM and POLCA principles.\nSupply Chain.\nQRM encourages companies to work with suppliers to reduce their MCT. Long supplier lead times can incur \"hidden\" costs such as high inventory, freight cost for rush shipments, unplanned engineering changes creating obsolete inventory, and reduced flexibility to respond to demand changes. QRM recommends that MCT be included as a significant factor in sourcing decisions.\nNew Product Introduction.\nQRM highlights strategic advantages of rapid New Product Introduction (NPI). Applying the MCT metric to the NPI process provides valuable information on the current NPI performance. Based on these findings, QRM encourages managers to rethink cost-based decisions in terms of their impact on the NPI MCT. For example, cost-based purchasing policies can result in long purchasing times for prototype materials, in turn delaying the NPI.\nImplementation.\nQRM theory recommends following four common steps when implementing QRM:\nCreating a QRM mindset.\nQRM implementation requires company personnel to embrace the strategy's time-based principles. In a first step, a team of management and employees trained in QRM principles should compile a list of wastes due to long MCT, creating awareness for the negative impact of long lead times on operations.\nIf the company decides to take action, QRM theory recommends the creation of an organizational framework for the implementation effort. In this framework, a high-level QRM Steering Committee oversees all QRM efforts, while a QRM Champion – an experienced employee with sound QRM training – is charged with driving and overseeing projects on a day-to-day basis.\nWith this structure in place, the Steering Committee can pick a set of products as the target for the first QRM project.\nChanging of organizational structure.\nFollowing the general direction of the Steering Committee, a cross-functional planning team starts studying the project, including a detailed analysis of the MCT, product volumes, strategic needs and other factors. This analysis leads to the definition of the FTMS for the QRM project. Using QRM principles, the planning team designs a QRM cell for the FTMS.\nWith approval from management, an implementation team consisting of the people in the new cell and members of the planning team can start training activities, cross-training of operators and – if needed – relocation of equipment to launch the cell. After cell launching, the implementation team continues support for the new cell and measures MCT to monitor lead time changes.\nInclusion of system dynamics.\nDuring both design of the cell and its operation, the implementation team should reexamine policies on utilization to properly plan the loading of the cells and to maintain spare capacity.\nFurthermore, cells teams should be encouraged to engage in a program of batch size reduction.\nEnterprisewide expansion of QRM.\nAfter completing the initial project, the company needs to evaluate the results of these QRM efforts and publicize successes throughout the organization. Following the same pattern as described above, the company should identify additional FTMSs for other QRM projects and start the implementation process. As more cells are formed, restructuring of the MRP system and implementation of POLCA may become necessary.\nTo maximize benefits of a time-based management strategy, QRM projects should span across office operations, the shop floor and supply chain.\nPractice.\nQuick Response Manufacturing is used by a variety of companies from different sectors worldwide. As an enterprisewide strategy, QRM has found applications in all areas of the company from shop floor to office operations to supply chain and beyond. In the apparel industry, QRM has also become closely intertwined with the concepts of Fast fashion (Sweatshop) and Fast Fit, both of which are intended to reduce the timeframes typically associated with bringing catwalk style to the high street.\nMany companies use QRM to address lead time issues in some parts of their organization or as an addition to existing continuous improvement efforts such as Lean, Six Sigma or others.\nAnother group of companies including Alexandria Extrusion, Omnipress, RenewAire and Phoenix Products have transformed their entire operation according to QRM principles making full use of QRM's enterprisewide reach.\nIn a 2008 article in Barron's magazine profiling the five companies most successful at boosting their sales and cash flow from among the 500 largest (by sales) publicly traded companies in the U.S. and Canada, Merrill Miller, chairman and CEO of National Oilwell Varco mentions improved manufacturing efficiencies based on QRM as a large part of NOV's growth.\nIn recent years, QRM principles have also found applications in the healthcare and pharmaceutical sector.\nCenter for Quick Response Manufacturing.\nFounded in 1993 by Rajan Suri, along with a few U.S. Midwest companies and academic colleagues at the University of Wisconsin-Madison, the Center for Quick Response Manufacturing has been a driving force in the development and implementation of QRM.\nOrganized as a public-private consortium including faculty, students and company members, the Center has assisted more than 220 companies in applying QRM principles over the past 20 years.\nThe Center provides general information on QRM and hosts a variety of training events each year. Companies interested in implementing QRM can become members of the Center and take part in improvement projects conducted in cooperation with engineering students and university faculty.\nFollowing the public-private partnership model, a new QRM Center at HAN University of Applied Sciences in Arnhem, Netherlands (founded 2010) is helping European companies implement QRM strategies.\nBook.\nT.C.E. Cheng, T.M. Choi (Eds.). Innovative Quick Response Programs in Logistics and Supply Chain Management, Springer, International Handbooks on Information Systems, 2010.", "Engineering,_Manufacturing": 1.0000069141, "qwen": "Yes"}
{"id": "29138975", "revid": "596616", "url": "https://en.wikipedia.org/wiki?curid=29138975", "title": "Backshop", "text": "A backshop or back-shop is a specialized store or workshop found in service industries, such as locomotive and aircraft repair. Most repairs are carried out in small workshops, except where an industrial service is needed.\nIn the military, backshops repair parts are known as shop-replaceable units (SRUs). These are commonly-stocked subassemblies of a larger system, such as circuit cards components of a line-replaceable unit (LRU), designed to be repaired at the field level. Repair at this level is known as field-level maintenance or intermediate-level (I-level) maintenance. \nCalibration and repair of United States Air Force test equipment is conducted at shops known as precision measurement equipment laboratories.", "Engineering,_Manufacturing": 0.9999907017, "qwen": "Yes"}
{"id": "29173096", "revid": "41807748", "url": "https://en.wikipedia.org/wiki?curid=29173096", "title": "TL.37", "text": "The TL.37 was an Italian military artillery tractor of World War II. It was manufactured by SPA (\"Società Piemontese Automobili\"), an Italian car maker that was a subsidiary of Fiat.\nDevelopment and history.\nThe tractor was chosen for the Royal Italian Army in 1938 as the result of a design competition between SPA and \"Breda Meccanica Bresciana\" for a light artillery tractor. It was subsequently used during World War 2 by all the Italian forces and was bought by Hungary. After the Italian Armistice in 1943, it continued to be used by German forces. Post–war, it was in service until 1948 with the Italian Navy.\nThe vehicle was notable for having four-wheel steering, that enabled it to have a turning circle. It was able to pull artillery pieces of 75mm and 100mm at a speed of on road, carrying five gun–crew in addition to the driver and of artillery ammunition. It was also able to climb a 40-degree slope.\nA self-propelled gun variant was also built, with a Cannone da 75/27 modello 11 fitted at the rear. The TL.37 was also the basis for a general–purpose truck, the Fiat–SPA AS.37, and two armoured cars the Fiat–SPA S37 (\"Fiat-SPA Autoprotetto S37\") and the Fiat-SPA AS43.", "Engineering,_Manufacturing": 0.9999945164, "qwen": "Yes"}
{"id": "68645970", "revid": "42209205", "url": "https://en.wikipedia.org/wiki?curid=68645970", "title": "Pettibone (company)", "text": "Pettibone, founded as Pettibone Mulliken, is a manufacturer of material handling equipment based in Baraga, Michigan. The company started doing business in 1881, and manufactures various cranes and other material handling vehicles, many designed specifically for railroad use.\nHistory.\nPettibone Mulliken was founded in 1881 in Chicago, Illinois with Alfred H. Mulliken as president. Initially, the company's biggest product was railroad track and switch equipment.\nBy 1929, the company's manufacturing facilities in Chicago occupied 32 acres.\nWhile primarily a manufacturer of cranes and other material handling equipment, the company received a $3,817,844 contract for artillery material from the United States Department of War in 1940, on the eve of U.S. entry into World War II. During the war, the company continued to manufacture artillery for the United States Armed Forces.\nPettibone today.\nToday, the company is known simply as Pettibone. It primarily manufactures cranes and other material handling equipment, some of which is still sold specifically for the rail industry.\nPettibone is most known for its cranes, manufactured under the Speed Swing line. Pettibone cranes are used by railroads for a variety of applications, including lifting rails and moving ties.", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "5584703", "revid": "20695403", "url": "https://en.wikipedia.org/wiki?curid=5584703", "title": "Surface feet per minute", "text": "Surface feet per minute (SFPM or SFM) is the combination of a physical quantity (\"surface speed\") and an imperial and American customary unit (\"feet per minute\" or \"FPM\"). It is defined as the number of linear feet that a location on a rotating component travels in one minute. Its most common use is in the measurement of cutting speed (surface speed) in machining. It is a unit of velocity that describes how fast the cutting edge of the cutting tool travels. It correlates directly to the machinability of the workpiece material and the hardness of the cutting tool material. It relates to spindle speed via variables such as cutter diameter (for rotating cutters) or workpiece diameter (for lathe work).\nSFM is a combination of \"diameter\" and the \"velocity\" (RPM) of the material measured in feet-per-minute as the spindle of a milling machine or lathe. 1 SFM equals 0.00508 m/s (meter per second, the SI unit of speed). The faster the spindle turns, and/or the larger the diameter, the higher the SFM. The goal is to tool a job to run the SFM as high as possible to increase hourly part production. However some materials will run better at specific SFMs. When the SFM is known for a specific material (\"ex 303 annealed stainless steel = 120 SFM for high speed steel tooling\"), a formula can be used to determine spindle speed for live tools or spindle speeds for turning materials.\nIn a milling machine, the \"tool\" diameter is used instead of the \"stock\" diameter in the following formulas when the tool is revolving and the stock is stationary.\nSpindle speed can be calculated using the following equation:\nSFM can be calculated using the following equation:", "Engineering,_Manufacturing": 0.9999902248, "qwen": "Yes"}
{"id": "38138132", "revid": "44930130", "url": "https://en.wikipedia.org/wiki?curid=38138132", "title": "Columbia Manufacturing Inc.", "text": "Columbia Manufacturing Inc. is a company located in Westfield, Massachusetts that manufactures chairs, desks, and other materials. In the education industry, it is best known for making the desk chair Model 114, which is used across the United States. Founded in 1877, it was once owned by Pope Manufacturing Company and was the brand that manufactured bicycles for the company. After Pope filed for bankruptcy in 1915, Columbia continued on to manufacture bicycles in Westfield. As of the 2010s, Columbia-branded bicycles are marketed by Columbia Bicycles, a subsidiary of Ballard Pacific.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "38163966", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=38163966", "title": "DSP coupling", "text": "A \"DSP coupling\" is a self-sealing symmetrical coupling which is secured by inter-connecting two couplings together.\nIt is closed by turning the locking ring on the triangular part of the opposed DSP coupling.\nExtra closure can be applied by locking the connection with couplings wrench.\nThe DSP coupling locking principle is similar to that of the guillemin coupling.\nHowever, there are differences to the preformed serration on the locking ring and the design of the lugs.\nThe locking ring of DSP couplings can be turned up to 45°.\nDSP coupling are used as fire-fighting couplings. They are typical in for e.g. France and Belgium.\nDSP couplings are symmetrical.\nDSP comes in different sizes. (e.g. DN40 DN65 DN100).\nTypical materials for the coupling are aluminum, brass and bronze.\nFor the Origin or meaning of \"DSP\" there is only speculation.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "38170215", "revid": "45382375", "url": "https://en.wikipedia.org/wiki?curid=38170215", "title": "Amada Miyachi America", "text": "AMADA WELD TECH, a subsidiary of AMADA WELD TECH CO., LTD, designs and manufactures equipment and systems for resistance welding, laser welding, laser marking, laser cutting, laser micro machining, hermetic sealing, micro tig welding, and hot bar reflow soldering and bonding. Established in 1948, AMADA WELD TECH is headquartered in Monrovia, California, US. The company's equipment is used in numerous industries, chief among which are medical, aerospace, automotive, batteries, and electronic components.\nAMADA WELD TECH has approximately 200 employees, with 7 sales and manufacturing offices serving about 12,000 customers worldwide. More than 80,000 items are manufactured annually. The company is certified to , China Compulsory Certificate (CCC), European Conformity (CE), and Canadian Standards Association (CSA) quality certifications.\nAMADA WELD TECH CO., LTD..\nAMADA WELD TECH's parent company, AMADA WELD TECH CO., LTD., was founded in 1972 to manufacture and market semiconductor-related measuring instruments and welding control equipment in response to the demand for quality control in the automobile, television, and electronics industries. The company incorporated microprocessors and other electronic devices into its resistance welders to enable high quality precision joining and monitoring and analysis. Its Weld Checkers™ are used worldwide for weld monitoring.\nIn 1984, the company developed a neodymium-doped yttrium aluminum garnet  laser welder that allowed for more precise and micro welding, and this product line became a central component of the company's business, along with resistance welding. In 2006, the company developed the first Yb: fiber laser welder in Japan.\nAMADA WELD TECH CO., LTD. has more than 600 employees (consolidated), in 10 sales offices and 2 factories in Japan, and 7 subsidiary companies (AMADA WELD TECH Inc., AMADA WELD TECH Gmbh, AMADA WELD TECH Korea Co., Ltd., AMADA WELD TECH Shanghai Co., Ltd., Amada (Thailand) Co., Ltd., AMADA WELD TECH India Pvt., Ltd., AMADA WELD TECH Taiwan CO., Ltd., and Amada Vietnam Co., Ltd. and 4 factories overseas (China, USA, Germany, Thailand). Annual revenue is ¥20 billion.\nAMADA WELD TECH is an AMADA Group Company. It is headquartered in Isehara, Kanagawa, Japan and develops, manufactures, sells, and services products and systems for metal sheet processing, metal cutting, pressing, and machine tooling. The company was established in 1946 and is listed on the Tokyo Stock Exchange (6113:Tokyo). It has 60 subsidiaries (17 in Japan and 43 overseas) and more than 7000 employees worldwide. Annual revenue exceeds ¥200 billion.\nProducts.\nAMADA WELD TECH specializes in the design and manufacture of welding, marking, cutting and bonding equipment, as well as automated systems. Major products include:\nApplications.\nAMADA WELD TECH currently offers seven different technologies, which the company combines to create end-to-end assembly joining solutions to facilitate reliable and repeatable welding. A few of the key application areas include:\nPatents.\nAMADA WELD TECH has been awarded numerous patents for its resistance and laser welding inventions, over the period 1971 through the present, including the following:", "Engineering,_Manufacturing": 0.9999949932, "qwen": "Yes"}
{"id": "34418155", "revid": "35936988", "url": "https://en.wikipedia.org/wiki?curid=34418155", "title": "Laser rapid manufacturing", "text": "Laser Rapid Manufacturing (LRM) is one of the advanced additive manufacturing processes that is capable of fabricating engineering components directly from a solid model.\nTechnique.\nIn this technique, a solid model of the component to be fabricated is made either by 3D imaging system or by designer using computer-aided design (CAD) software or by math data as an output of numerical analysis. Thus obtained model is sliced into thin layers along the vertical axis. The thin layers are converted into corresponding numerical controlled (NC) code and are sent to LRM station in suitable format (e.g. G&M code). LRM station employs a laser beam as a heat source to melt a thin layer on the surface of the substrate/deposited material and fed material to deposit a new layer as per shape and dimensions defined in NC code. A number of such layers deposited one over another and it results in three-dimensional (3D) components directly from the solid model.\nBenefits.\nLRM eliminates many manufacturing steps such as materials-machine planning, man-machine interaction, intermittent quality checks, assembly and related human errors etc. Therefore, LRM offers many advantages over conventional subtractive techniques, such as reduced production time, better process control and capability to form functionally graded parts. It is also an attractive candidate for refurbishing applications because of low heat input, limited dilution with minimal distortion and capability of adding finer near-net shaped features to the components.\nSimilar techniques.\nManufacturing techniques, similar to LRM, are being developed with different names at various laboratories, such as Laser Engineered Net Shaping (LENSTM) at Sandia National Laboratories (USA), Freeform Laser Consolidation at National Research Council (Canada), Selective Laser Powder Remelting (SLPR) at Fraunhofer Society (Germany), Selective Laser Cladding (SLC) at the University of Liverpool (UK), Shape deposition Manufacturing (SDM) at Stanford University (USA), Direct Metal Laser Sintering (DMLS) at Electrolux Rapid Development (Finland), Direct Metal Deposition at the University of Michigan, Automated Laser Fabrication (ALFa) at the University of Waterloo, Canada etc.", "Engineering,_Manufacturing": 0.9998881817, "qwen": "Yes"}
{"id": "26203749", "revid": "5844488", "url": "https://en.wikipedia.org/wiki?curid=26203749", "title": "F crimp", "text": "F-Crimp is a type of solderless electrical crimp connection. It is not related to the F connector common in RF equipment.\nIt is sometimes referred to as \"open-barrel\", which is technically a more general term including crimp types such as \"Weather Pack\" and \"Metri Pack\".\nF-Crimp is a more mechanically robust crimp connection compared to the common barrel-crimp type readily available at retail locations (Radio Shack, Home Depot, \"etc.\"). It also has an optional second crimp section that crimps to the insulation, providing strain relief. Because of these characteristics, automobiles use F-Crimp almost exclusively. F-Crimp was devised to eliminate the need for soldered connections—crimping can be preferred to soldering in mass production because it is easier to reproduce reliable connections. These connections, when made with ratcheting application tooling, provide a solderless, \"gas-tight\" connection. F-Crimp connections are never soldered as application of solder can lead to fracturing of the wire conductor.\nThe term F-Crimp was originally coined by AMP Incorporated (now TE Connectivity), however terminals of this style are currently manufactured by multiple companies. Crimpers are available from multiple sources: manufacturers of the connectors typically offer industrial crimp devices for high volume production, and specialized hand tools companies such as Ideal, Eclipse and Greenlee (formerly Paladin) offer dies for hand crimpers. For instance, Ideal die #30-586 and Paladin die #2033 are designed for open barrel / F-Crimp connectors. Non-AMP crimpers are available in \"ratcheting\" (\"Certi-Crimp\") and non-ratcheting versions, but only ratcheting types are suitable for production applications, with non-ratcheting types being suitable for occasional, or \"field\" repairs. Non-ratcheted crimps must \"never\" be used in \"mission critical\" applications.", "Engineering,_Manufacturing": 0.9999266863, "qwen": "Yes"}
{"id": "70081354", "revid": "44920599", "url": "https://en.wikipedia.org/wiki?curid=70081354", "title": "Belur Industrial Area", "text": "Belur Industrial Area (Abbreviation : BIA) is an industrial area of the Dharwad city in India and it is one of the biggest industrial areas in Karnataka. lies on the Dharwad-Belgaum Highway. It houses small, medium, and large-scale industries. The industrial area is known for engineering, electrical goods such as: CNC Machine tools, GDC dies & moulds transformers, motors and generators, textile (silk), hydraulics, machine tool industries and Rubber moulding industries.", "Engineering,_Manufacturing": 0.9991253018, "qwen": "Yes"}
{"id": "50403904", "revid": "5846", "url": "https://en.wikipedia.org/wiki?curid=50403904", "title": "Decapping", "text": "Decapping (decapsulation) or delidding of an integrated circuit is the process of removing the protective cover or integrated heat spreader (IHS) of an integrated circuit so that the contained die is revealed for visual inspection of the micro circuitry imprinted on the die. This process is typically done in order to debug a manufacturing problem with the chip, or possibly to copy information from the device, to check for counterfeit chips or to reverse engineer it. Companies such as TechInsights and ChipRebel decap, take die shots of, and reverse engineer chips for customers. Modern integrated circuits can be encapsulated in plastic, ceramic, or epoxy packages.\nDelidding may also be done in an effort to reduce the operating temperatures of an integrated circuit such as a processor, by replacing the thermal interface material (TIM) between the die and the IHS with a higher-quality TIM. With care, it's possible to decap a device and still leave it functional.\nMethod.\nDecapping is usually carried out by chemical etching of the covering, laser cutting, laser evaporation of the covering, plasma etching or mechanical removal of the cover using a milling machine, saw blade or by desoldering and cutting. The process can be either destructive or non-destructive of the internal die.\nChemical etching usually involves subjecting the (if made of plastic) IC package to concentrated or fuming nitric acid, heated concentrated sulfuric acid, white fuming nitric acid or a mixture of the two for some time, possibly while applying heat externally with a hot plate or hot air gun, which dissolve the package while leaving the die intact. The acids are dangerous, so protective equipment such as appropriate gloves, full face respirator with appropriate acid cartridges, a lab coat and a fume hood are required.\nLaser decapping scans a high power laser beam across the plastic IC package to vaporize it, while avoiding the actual silicon die.\nIn a common version of non-destructive, mechanical delidding, one removes the IHS of an IC such as a computer processor using an oven to soften the solder (if present) between the IHS and the die(s) and using a knife to cut the adhesive in the periphery of the IHS, which joins the IHS with the processor package substrate, which is often a specialized printed circuit board often only called a substrate or sometimes an interposer. The die(s) are mounted on the substrate using flip chip.", "Engineering,_Manufacturing": 0.9998576641, "qwen": "Yes"}
{"id": "50423059", "revid": "32942831", "url": "https://en.wikipedia.org/wiki?curid=50423059", "title": "Prohibited Steps Order", "text": "A Prohibited Steps Order is a court order in the United Kingdom common in divorce and separation cases. An example of where a Prohibited Steps Order might be applied for is to prevent one parent from taking a child out of the country.", "Engineering,_Manufacturing": 0.9999988079, "qwen": "Yes"}
{"id": "11955150", "revid": "21417351", "url": "https://en.wikipedia.org/wiki?curid=11955150", "title": "Grown-junction transistor", "text": "The grown-junction transistor was the first type of bipolar \"junction\" transistor made. It was invented by William Shockley at Bell Labs on June 23, 1948 (patent filed June 26, 1948), six months after the first bipolar point-contact transistor. The first germanium prototypes were made in 1949. Bell Labs announced Shockley’s grown-junction transistor on July 4, 1951.\nAn NPN grown-junction transistor is made of a single crystal of semiconductor material which has two PN junctions grown into it. During the growth process, a seed crystal is slowly pulled from a bath of molten semiconductor, which then grows into a rod-shaped crystal (boule). The molten semiconductor is doped N-type at the start. At a predetermined moment in the growth process a small pellet of a P-type dopant is added, almost immediately followed by a somewhat larger pellet of an N-type dopant. These dopants dissolve in the molten semiconductor changing the type of semiconductor subsequently grown. The resulting crystal has a thin layer of P-type material sandwiched between sections of N-type material. This P-type layer may be as little as a thousandth of an inch (25 μm) thick. The crystal is sliced, leaving the thin P-type layer in the center of the slice, then cut into bars. Each bar is made into a transistor by soldering its N-type ends to supporting and conducting leads, then welding a very fine gold lead to the central P-type layer, and finally encasing in a hermetically sealed can. A similar process, using the opposite dopants, makes a PNP grown-junction transistor.\nThe most difficult part of this process is welding the gold wire to the base layer, as the wire may have a larger diameter than the thickness of the base. To facilitate this operation, the gold wire is pointed or flattened until the end is thinner than the base layer. The tip of the gold wire is slid along the bar until electrical resistance measurement shows it is in contact with the base layer. At this time a pulse of current is applied, welding the wire in place. Unfortunately sometimes the weld is too large or slightly off center in the base layer. To avoid shorting the transistor, the gold wire is alloyed with a small amount of the same type dopant as used in the base. This causes the base layer to become slightly thicker at the point of the weld.\nGrown-junction transistors rarely operated at frequencies above the audio range, due to their relatively thick base layers. Growing thin base layers was very hard to control and welding the wire to the base became harder the thinner it got. Higher-frequency operation could be obtained by welding a second wire on the opposite side of the base, making a tetrode transistor, and using special biasing on this second base connection.", "Engineering,_Manufacturing": 0.9986381531, "qwen": "Yes"}
{"id": "68960625", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=68960625", "title": "1999 Nigerian House of Representatives elections in Kwara State", "text": "The 1999 Nigerian House of Representatives elections in Kwara State was held on February 20, 1999, to elect members of the House of Representatives to represent Kwara State, Nigeria.\nResults.\nAsa/Ilorin West.\nAPP candidate Gbemisola Ruqayyah Saraki won the election, defeating other party candidates.\nBaruten/Kaiama.\nPDP candidate Idris S. Abubakar won the election, defeating other party candidates.\nEdu/Moro/Patigi.\nPDP candidate Yunusa Y. Ahmed won the election, defeating other party candidates.\nEkiti/Isin/Irepodun/Oke-ero.\nAPP candidate Basair Bola Oni won the election, defeating other party candidates.\nIlorin East/South.\nAPP candidate Farouk A. O. Farouk won the election, defeating other party candidates.\nOffa/Oyun/Ifelodun.\nAPP candidate Rauf Kolawole Shitu won the election, defeating other party candidates.", "Engineering,_Manufacturing": 0.999945879, "qwen": "Yes"}
{"id": "68990776", "revid": "6972236", "url": "https://en.wikipedia.org/wiki?curid=68990776", "title": "Nada Sanders", "text": "Nada R. Sanders is an American university professor specializing in forecasting and supply-chain management. She is the Distinguished Professor of Supply Chain Management at the D’Amore-McKim School of Business at Northeastern University. She is also a research scholar, academic editor, reference book author, keynote speaker, business consultant, and corporate board member. Her forecasts describing the impact of the economic crisis on supply disruptions resulting from the COVID-19 pandemic received media coverage. Her latest book \"The Humachine\" (co-authored with John D. Wood) explores the influence of artificial intelligence over world business and culture.\"\"\nEducation.\nSanders' university degrees include PhD in operations management and logistics from the Fisher College of Business, Ohio State University, also an MBA and a BS in mechanical engineering.\nCareer.\nSanders has successively been the \"West Chair\" at the Neely School of Business at Texas Christian University (2007–2009), \"Iacocca Chair\" of Supply Chain Management at Lehigh University (2009–2014), and \"Distinguished Professor of Supply Chain Management\" at the D’Amore-McKim School of Business at Northeastern University (2014 to present).\nHer research has centered on topics such as forecasting methods, management technologies, and resilience of supply chains, her works being commonly cited by subject reviews, and referred as reading in university courses covering these matters. Her research is cited in current Wikipedia entries on Forecasting, Global value chain, Electronic business, Logistics, Operations management. Procurement, Supply chain, and Supply chain management.\nIn 1996, Sanders was ranked among major contributors to the field of production and operations management in the US in preceding years, according to a study from the David Eccles School of Business, University of Utah. She has been a keynote speaker at conferences in her specialties-\nAs an institutional executive, she has served as a President of the Production and Operations Management Society (POMS, 2019), a Fellow and vice-president of Decision Sciences Institute, a member of the Board of Economic Advisors of the Association of Industries of Massachusetts (AIM), and a member of the Board of Consultants of the International Institute of Forecasters (IIF).\nAs an editor, Sanders is a member of the editorial boards of several academic journals, among them the Journal of Business Logistics, the Journal of Supply Chain Management, and Production and Operations Management. She has also been a co-editor of several special journal issues, including \"Big Data Driven Supply Chain Management\" (Production and Operations Management\", 2017\"), \"Big Data Driven Forecasting in Supply Chain Management\" (International Journal of Forecasting, 2017), \"Perspectives on Big Data\" (Operations Management, 2018), \"Sustainable Supply Chains in a Digital Interconnected World,\" (Journal of Business Logistics\",\" 2019), and \"Using Interdisciplinary Research to Address Contemporary SCM Problems\" (Journal of Business Logistics, 2016).\nWorks.\nPapers.\nSanders has published over 120 articles in peer-reviewed academic journals which have been cited over 6,400 times; her most cited papers are:\nHer most recent articles refer to the impact of Artificial intelligence on business and supply chains:", "Engineering,_Manufacturing": 0.9947693944, "qwen": "Yes"}
{"id": "1227058", "revid": "45179011", "url": "https://en.wikipedia.org/wiki?curid=1227058", "title": "Wire stripper", "text": "A wire stripper is a small, hand-held device used to strip the electrical insulation from electric wires.\nTypes.\nManual.\nA US-style simple manual wire stripper is a pair of opposing blades much like scissors or wire cutters. The addition of a center notch makes it easier to cut the insulation without cutting the wire. This type of wire stripper is used by rotating it around the insulation while applying pressure in order to make a cut around the insulation. Since the insulation is not bonded to the wire, it then pulls easily off the end. This type of wire stripper can be used on wires of any size. Another type of manual wire stripper is very similar to the simple design previously mentioned, except this type has several notches of varying size. This allows the user to match the notch size to the wire size, thereby eliminating the need for twisting, but can only be used on wire sizes that approximately match one of the notches. Once the device is clamped on, the remainder of the wire can simply be pulled out, leaving the insulation behind.\nEuropean-style wire strippers look more like a notched pincer, with a grab that is adjusted with a screw.\nCompound automatic.\nThe compound automatic wire stripper was first patented in 1915 by Stuart G. Wood of Brooklyn, NY. The design was refined by Herman Gerhard Jan Voogd of the Netherlands eliminating the awkward 4 bar mechanism taking on the general outline that it has kept since. Wood, now of Rockville IL, added reinforcements, replaceable blades, and blade stops in 1943 The 1943 design was also equipped to block the halves open after stripping to avoid crushing the freshly stripped wire as it returned to its rest position. A second actuation released the mechanism to return to the rest position. The action was further refined by Wood and finally, in 1959, by Eugene D. Hindenburg of DeKalb, IL. The 1959 refinement of the action shifted the sequence of operations so that the stripping blades opened before any other part of the mechanism began to return to the rest position while the clamping jaws retraced the sequence of operation, remaining closed until the handles were fully released.\nWhen engaged, a compound automatic wire stripper first simultaneously grips the wire in one side and in the other side closes its shaped blades cutting the insulation around the conductor. After the sides have completed their strokes the two sides of the mechanism spread apart to push the cut tube of insulation from the end of the conductor. To use it, one simply places the wire in the jaws at the cutting slot matching the size of the conductor and squeezes the handles together. This device allows even a novice to strip most wires very quickly. The compound automatic wire stripper's cutter must be short, because it causes the jaws to twist, as described by Wood in the 1943 patent. All wire strippers are inherently limited to those wire sizes the cutting jaw notches will accommodate. A compound automatic wire stripper's short cutter limits it to fewer notches and a smaller range of wire sizes than most other types of wire strippers. The accuracy of the cutting blade opening determines the smallest conductor that can be reliably stripped. If the cutter opening is too small it will impinge on the conductor causing excess friction and more tension than the wire can withstand. If the cutter opening is too large the tension required to tear the remaining annulus of uncut insulation may be greater than the wire can withstand. Some models have an adjustable grip tension, to adjust the clamping force of the gripping jaw. The knob below the jaw on the yellow automatic strippers in the image below is a grip tension adjustment. Although in principle applicable to wire of any size, compound automatic wire strippers that are widely available have cutters that can accommodate conductors in a range of sizes no larger than 8 AWG nor smaller than 26 AWG, but not the entire range.\nLaser wire stripper.\nA laser wire stripper is a computer-controlled machine, much like a CNC router, which uses a laser to burn off the insulation of the wire. Laser wire stripping machines are used mostly for very fine gauge wires since they do not damage the conductor. A typical CO2 laser wire stripping machine should be capable of stripping the insulation from any size wire.", "Engineering,_Manufacturing": 1.0000046492, "qwen": "Yes"}
{"id": "1699649", "revid": "45653908", "url": "https://en.wikipedia.org/wiki?curid=1699649", "title": "Tebis", "text": "Tebis (\"Technische Entwicklung Beratung und Individuelle Software\") is a CAD/CAM software provided by Tebis AG, with headquarters in Martinsried near Munich/Germany.\nDevelopment locations: Martinsried and Norderstedt, Germany\nInternational locations: China, Spain, France, Italy, Portugal, Sweden, United Kingdom, USA.\nFunctionality.\nTebis is a CAD/CAM software for industries such as die, mold or model manufacturing. The software is primarily to create toolpaths for machining operations such as drilling, milling and turning, but also for Wire EDM and sinker EDM. These toolpaths control multi-axis CNC machines. Other applications include manufacturing planning, design, reverse engineering, quality assurance, CNC machining and assembly. The software features interfaces for neutral file formats as well as proprietary formats of third-party manufacturers (STEP 203/214, VDAFS, IGES, DXF, STL, Parasolid, Catia V4/V5, Creo, SolidWorks, NX, JT, Inventor, Nastran, AutoForm).\nIndustrial application.\nThe programs are used in manufacturing companies of all sizes, from small and medium-sized companies to OEMs in the automotive and aerospace industries and their suppliers.\nThe following is a small sampling of companies who use the CAM system from Tebis.\nThe history of Tebis.\nTebis was founded in 1984. Following initial consulting jobs and business software projects, Tebis shifted its focus after six months to CAD/CAM. The first technical product was a PC-based station, which used a drawing board equipped with a position-measuring system to digitize transparent plans and convert them to scribed programs for milling machines.\nVersions 1.0 to 1.0.4 constituted the first Tebis CAD/CAM system. As one of the first 3D systems, Tebis ran exclusively on PCs (DOS). Two monitors were required for its operation: One monitor displayed the real commands, while the other showed the geometries in 4 panels. The input commands were entered using a digitizer tablet. The milling programs were calculated only for individual surfaces. Because of the small RAM (256 bytes) in the NC machines of the 1980s, Tebis provided a DNC connection to enable postprocessing via a V24 line next to the NC machine.\nThe Tebis Version 2.0 with a graphical user interface was introduced in 1989. It is still used today in a much more advanced form, and is distinct from common Windows interfaces. This version made it possible to animate geometries onscreen in real-time. Tebis Automill technology, which allows users to calculate milling paths across surfaces, was introduced in Version 2.1.\nTebis Version 3.0 was presented in 1993. The system was modularized and expanded for operation under the SCO UNIX, HP-UX, IRIX and AIX operating systems. Version 3.1 included the Milling Wizard, version V3.2 featured interactive CAD and version V3.3 offered the first integration of a tool library and parameterized administration for all NC calculations. In Version 3.4, modules for the simulation of machining at a virtual CNC machine the design of electrodes for EDM, and 2.5D milling and drilling were added. Starting with Version 3.5, variable machining templates can be used for even better NC programming automation. For the first time this version also included the Job Manager as a central control element for all machining steps. The CAD module for BREP design was integrated in the software, enabling Tebis to be used for the entire manufacturing process in die, mold and model manufacturing. Version 4.0 was provided with a new user interface specifically designed for CAD/CAM applications and a new platform for 2.5D and 3D feature-based NC automation. For the first time, this version supported CNC lathes and industrial robots, and the manufacturing technologies of laser hardening and laser weld cladding.\nThe current Tebis Version 4.1 was launched in 2020 with an internally-developed parametric-associative CAD system base. The hybrid CAD system combines free-form surfaces, solids and digitized data and provides Tebis template technology also in the CAD environment. Parametric CAD templates automate design and CAD manufacturing preparation. The user interface has also been optimized in terms of simplicity and automation for CAM users.\nTebis is one of the global market leaders in CAM software. The owner-managed company also has its own consulting unit working with companies primarily in die, mold and model manufacturing. Services include industry-specific process and management consulting and optimizing the processes of these companies.\nAfter acquiring a division of ID Ingenieurgesellschaft für Datentechnik mbH, Tebis now also offers a manufacturing execution system (MES) called ProLeiS that can be integrated in the CAD/CAM application.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "50921584", "revid": "17521300", "url": "https://en.wikipedia.org/wiki?curid=50921584", "title": "Prusa i3", "text": "The Prusa i3 is a family of fused deposition modeling 3D printers, manufactured by Czech company Prusa Research under the trademarked name Original Prusa i3. Part of the RepRap project, Prusa i3 printers were called the most used 3D printer in the world in 2016. The first Prusa i3 was designed by Josef Průša in 2012, and was released as a commercial kit product in 2015. The latest model (Prusa MK4 on sale as of March 2023) is available in both kit and factory assembled versions. The Prusa i3's comparable low cost and ease of construction and modification made it popular in education and with hobbyists and professionals, with the Prusa i3 model MK2 printer receiving several awards in 2016. \nThe i3 series is released under an open source license, so many other companies and individuals have made variants of the printer.\nModels.\nRepRap Mendel.\nFirst conceived in 2009, RepRap Mendel 3D printers were designed to be assembled from 3D printed parts and commonly available off-the-shelf components (referred to as \"vitamins,\" as they cannot be produced by the printer itself). These parts include threaded rods, leadscrews, smooth rods and bearings, screws, nuts, stepper motors, control circuit boards, and a \"hot end\" to melt and place thermoplastic materials. A Cartesian mechanism permits placement of material anywhere in a cubic volume; this design has continued throughout development of the i3 series. The flat \"print bed\" (the surface on which parts are printed) is movable in one axis (Y), while two horizontal and two vertical rods permit tool motion in two axes, designated X and Z.\nPrusa Mendel.\nJosef Průša, a core developer of the RepRap project who had previously developed a PCB heated \"print bed\", adapted and simplified the RepRap Mendel design, reducing the time to print 3D plastic parts from 20 to 10 hours, and including 3D printed bushings in place of regular bearings. First announced in September 2010, the printer was dubbed Prusa Mendel by Průša himself. According to the RepRap wiki, \"Prusa Mendel is the Ford Model T of 3D printers.\"\nPrusa Mendel (Iteration 2).\nPrůša streamlined his Mendel design, releasing \"Prusa Iteration 2\" in November 2011. Parts changes allowed for snap-fit assembly (no glue required); fewer tools were needed to construct and maintain this version. Although not required, fine-pitch manufactured pulleys and LM8UU linear bearings were recommended over printed equivalents for \"professional\" results.\nPrusa i3.\nIn May 2012, Průša released a major redesign, focused on ease of construction and use, and no longer structured around the simplest available common hardware as previous RepRap printers were. The Prusa i3 design replaced the threaded-rod, triangular Z axis frame construction with a rigid, single-piece water jet cut aluminium vertical frame. This improved printing speed and accuracy by eliminating the need to erect, align and tighten the upper supports on the Mendel, which were easily skewed or twisted out of alignment from the base. M10 threaded rods were still used to support the heated bed Y axis. It used a single piece, food safe stainless steel hot end called the Prusa Nozzle which printed with 3 mm filament, and used M5 threaded rods as lead screws instead of M8.\nIn 2015, Průša released an i3 full kit under the brand name \"Original Prusa i3\". For about three months, the Prusa i3 was delivered set up for a proprietary 3 mm filament diameter (which retrospectively has been dubbed the \"mark zero\"), before the Mk1 update when it was switched to the more common filament diameter of 1.75 mm.\nPrusa i3 MK2 and MK2S.\nPrůša released the Prusa i3 MK2 in May 2016. It was the first hobby 3D printer with mesh bed leveling and automatic geometry skew correction for all three axes. Features included a larger build volume, custom stepper motors with integrated lead screws, a non-contact inductive sensor for auto-leveling, and a rewritten version of the Marlin firmware. Other new features include a polyetherimide print surface, Rambo controller board and an E3D V6 Full hotend. The Prusa MK2 became the first RepRap printer to be supported by Windows 10 Plug-and-Play USB ID.\nIn March 2017, Průša announced on his blog that the revised Prusa i3 MK2S would ship in place of the Prusa i3 MK2. Enhancements cited include U-bolts to hold the LM8UU bearings where cable ties had been used, higher quality bearings and rods, an improved mount for the inductance sensor, improved cable management, and a new electronics cover. An upgrade kit was offered to owners of the MK2 to add these improvements.\nPrusa i3 MK3 and MK2.5.\nIn September 2017, Prusa i3 MK3 was released, marketed as \"bloody smart.\" Starting with this model, the base and Y axis were assembled with aluminum extrusion, eliminating the last of the structural threaded rods from the Mendel design. Included were a new extruder with dual Bondtech drive-gears, quieter fans with RPM monitoring, faster print speeds, an updated bed leveling sensor, a new electronics board named \"Einsy\", quieter stepper motors with 128 step microstepping drivers and a magnetic heatbed with interchangeable PEI-coated steel sheets. Electrical components were updated to work with the new 24 volt power supply. The printer also offers dedicated sockets to connect Raspberry Pi Zero W running a fork of the open source OctoPrint software for wireless printing.\nEase-of-use features included a filament detector, allowing the printer to load filament when it is inserted, and to pause printing if the filament is jammed or runs out; error-correcting stepper motor drivers preventing layer shifts due to skipped steps; and recovery after power outages. The ambient temperature sensor both confirms suitable environment temperature and detects overheated electrical connections on the main board.\nExisting MK2 and MK2S users were offered a $199 partial upgrade named MK2.5, limited to features which are cheaper to upgrade. After negative feedback from the community, Prusa made available a more expensive $500 MK2S to MK3 full upgrade.\nPrusa i3 MK3S and MK3S+.\nIn February 2019, Prusa i3 MK3S was released, along with the Multi Material Upgrade 2S (MMU2S), which allows selecting any of 5 different materials for printing together automatically. MK3S changes include a simplified opto-mechanical filament sensor, improved print cooling, and easier access to service the extruder.\nPrusa made a running change starting November, 2020 to the Prusa i3 MK3S+. This model has a revised bed leveling sensor and minor parts changes.\nPrusa i3 MK4.\nIn March 2023, Prusa announced the i3 MK4 and the Multi Material Unit version 3 (MMU3). This model features a new i3 version of their \"Nextruder\" extruder system first seen on the Prusa XL, no-adjustment load cell bed leveling, a modular replaceable all-metal hot end, a color touchscreen, and die-cast aluminum frame, Y-carriage (heat bed support), and extruder frame. The 32-bit main processor board includes additional safety and monitoring circuits, a network connector, a port for the MMU3, and a Wi-fi module. This is Prusa's first Mendel-based design to include support for local and cloud monitoring and support.\nSwitching to 0.9 degree stepping motors, and the addition of input shaping and pressure advance, allow the Mendel-style design to print faster while avoiding ringing artifacts and other undesirable patterns imposed on the object being made, even though it does not have the advantages of the box-like structure of CoreXY printers. However, Průša has stated that print quality, not maximum speed, is their design goal. There is a provision for an accelerometer, often used in 3D printing for self-tuning of input shaping, but that component is not included in the final design.\nWhen announced, software for input shaping, touch screen operation, and sensor data collection were not finished, and the Multi Material Unit was not ready for release. Upgrade kits for earlier models likewise were not available for shipping.\nOther Prusa models.\nFollowing the MK3S, Prusa introduced unrelated models such as the Prusa SL1 (SLA printer), the Prusa Mini (with a cantilever arm) and Prusa XL (using a Core XY method inside a full-frame structure). These printers are not iterations of the Mendel frame design.\nVariants.\nWith all aspects of the design freely available under open source and open hardware terms, companies and individuals around the world have produced Prusa i3 copies, variants, and upgrades in assembled and kit form, with thousands offered for sale as early as 2015. Rather than compete directly with these, Prusa Research's strategy is to pursue continual refinement of its designs.\nComponents and materials.\nPlastic parts.\nAll Prusa i3 models use 3D printing filament as feedstock to make parts.\nLike other RepRap printers the Prusa i3 is capable of creating many of its own parts, with the designs freely available for repairs, replication, and redesign. Formerly these were printed in ABS plastic; Prusa Research now uses mostly PETG instead. Prusa Research maintains a \"print farm\" of 600 3D printers (as of October 2021) to manufacture the plastic parts for Original Prusa branded products.\nControl system.\nWhen the Prusa i3 design was first introduced in 2012, RepRap printers frequently used Open Hardware controllers such as an Arduino Mega combined with an Arduino shield providing the remaining circuitry, such as the RAMPS board. All-in-one versions such as the RAMBo board were becoming available. As a commercial product, Original Prusa i3 up to MK2 used Mini-Rambo. MK3 versions switched to Einsy Rambo boards to provide desired features such as quieter operation. The i3 MK4 uses xBuddy, the first 32-bit board used in the i3 series.\nAll Original Prusa products use Marlin 3D printing firmware.\nFirst layer control and bed leveling.\nWhen extruding the first layer, the print head must be a precise distance away from the print bed for proper adhesion. Many 3D printers rely on the user to complete this process by adjusting the height of the bed at several locations (\"bed leveling\"). To automate this process, Prusa i3 models from the MK2 in 2016 have a sensor to detect the height of the printbed at different locations, and then adjust for it when printing (\"auto-leveling\").\nThe PINDA series requires an electronic Z-height adjustment which may vary for different heat bed surfaces or different nozzles. The load cell sensor automatically compensates for variations in nozzle size, and thickness and expansion of the heated bed surface, eliminating stored settings for the purpose.\nFrames.\nThe distinguishing feature of the i3 from its predecessors is the vertical frame, which can take many forms. These include single sheet frames cut from steel or acrylic, box frames from plywood or medium-density fibreboard, and Lego. Inexpensive aluminum extrusion is commonly used, both by printer enthusiasts and by manufacturers of \"clone\" i3 printers. Some mass market i3 variants, such as many Shenzhen Creality products, use rollers against the extruded frame itself instead of precision rods and bearings to reduce cost and complexity.\nExtruders.\nBeyond the standard Prusa i3 filament extruders, others have created aftermarket extruders and enthusiast tool heads, including a MIG welder and a laser cutter. Průša offered a collection of functional cooking tools and programs under the name \"MK3 Master Chef Upgrade\" as an April Fools' Day gag in 2018.", "Engineering,_Manufacturing": 0.9999252558, "qwen": "Yes"}
{"id": "16983737", "revid": "45393810", "url": "https://en.wikipedia.org/wiki?curid=16983737", "title": "Ceramic mold casting", "text": "Ceramic mold casting, also known ambiguously as ceramic molding, is a group of metal casting processes that use ceramics as the mold material. It is a combination of plaster mold casting and investment casting. There are two types of ceramic mold casting: the \"Shaw process\" and the \"Unicast process\".\nThese casting processes are commonly used to make tooling, especially drop forging dies, but also injection molding dies, die casting dies, glass molds, stamping dies, and extrusion dies.\nShaw process.\nThe ', also known as the ', uses a mixture of refractory aggregate, hydrolyzed ethyl silicate, alcohol, and a gelling agent to create a mold. This slurry mixture is poured into a slightly tapered flask and a reusable pattern (\"i.e.\" the item used to create the shape of the mold) is used. The slurry hardens almost immediately to a rubbery state (the consistency of vulcanized rubber). The flask and pattern is then removed. Then a torch is used to ignite the mold, which causes most of the volatiles to burn-off and the formation of ceramic microcrazes (microscopic cracks). These cracks are important, because they allow gases to escape while preventing the metal from flowing through; they also ease thermal expansion and contraction during solidification and shrinkage. After the burn-off, the mold is baked at to remove any remaining volatiles. Prior to pouring metal, the mold is pre-warmed to control shrinkage.\nUnicast process.\nThe \"Unicast process\" is very similar to the Shaw process, except it does not require the mold to be ignited and then be cured in a furnace. Instead, the mold is partially cured so the pattern can be removed and it is then completely cured by firing it at approximately . If a metal with a low melting point is cast then the firing can be skipped, because the mold has enough strength in the \"green state\" (un-fired).\nCharacteristics.\nThe main advantages of ceramic molds are: a reusable pattern (the item used to create the shape of the mold), excellent surface finish, close dimensional tolerances, thin cross-sections, and intricate shapes can be cast. For undercuts and other difficult to cast features, part of the pattern can be made from wax in conjunction with a standard pattern; essentially using investment and ceramic mold casting techniques together. The main disadvantages are: it is only cost effective for small- to medium-sized production runs and the ceramic is not reusable. Ferrous and high-temperature non-ferrous are most commonly cast with these processes; other materials cast include: aluminum, copper, magnesium, titanium, and zinc alloys.\nWeight limits are 100 grams to several thousand kilograms (3.5 oz to several tons). Cross-sections as thin as are possible, with no upper limit. Typical tolerances are 0.1 mm for the first 25 mm (0.005 in for the first inch) and 0.003 mm per additional mm (0.003 in per each additional in). A draft of 1° is typically required. The typical surface finish is 2–4 um (75–150 uin) RMS.", "Engineering,_Manufacturing": 0.9996722937, "qwen": "Yes"}
{"id": "16986286", "revid": "42677165", "url": "https://en.wikipedia.org/wiki?curid=16986286", "title": "Full-mold casting", "text": "Full-mold casting is an evaporative-pattern casting process which is a combination of sand casting and lost-foam casting. It uses an expanded polystyrene foam pattern which is then surrounded by sand, much like sand casting. The metal is then poured directly into the mold, which vaporizes the foam upon contact.\nProcess.\nFirst, a pattern is usually made from polystyrene foam, which can be done many different ways. For small volume runs the pattern can be hand cut or machined from a solid block of foam; if the geometry is simple enough it can even be cut using a hot-wire foam cutter. \nIf the volume is large, then the pattern can be mass-produced by a process similar to injection molding. Pre-expanded beads of polystyrene are injected into a preheated aluminum mold at low pressure. Steam is then applied to the polystyrene which causes it to expand more to fill the die. The final pattern is approximately 97.5% air and 2.5% polystyrene. \nThe finished patterns can be hot glued to pre-made pouring basins, runners, and risers to form the final pattern. The pattern is then coated with a refractory material. The coated pattern (2) is placed in a flask and packed carefully with green sand (4) or a chemically bonded sand. \nFinally, the molten metal (1) is poured into the mold, which vaporizes the foam (3) allowing the metal to fill the entire mold. The vapor is simultaneously extracted from the flask through the sand.\nThe casting is allowed to cool and then dumped out of the flask (5) ready to use. The sand does not need to be reprocessed so it can be directly reused.\nDetails.\nThe minimum wall thickness for a full-mold casting is . Typical dimensional tolerances are 0.3% and typical surface finishes are from 2.5 to 25 µm (100 to 1000 µin) RMS. The size range is from to several tonnes (tons).\nFull-mold casting is often used to produce cylinder heads, engine blocks, pump housings, automotive brake components, and manifolds. Commonly employed materials include aluminium, iron, steel, nickel alloys, and copper alloys.\nAdvantages and disadvantages.\nThis casting process is advantageous for very complex castings, that would regularly require cores. It is also dimensionally accurate, requires no draft, and has no parting lines so no flash is formed. As compared to investment casting, it is cheaper because it is a simpler process and the foam is cheaper than the wax. Risers are not usually required due to the nature of the process; because the molten metal vaporizes the foam the first metal into the mold cools more quickly than the rest, which results in natural directional solidification.\nThe two main disadvantages are that pattern costs can be high for low volume applications and the patterns are easily damaged or distorted due to their low strength. If a die is used to create the patterns there is a large initial cost.\nHistory.\nThe first patent for an evaporative-pattern casting process was filed in April 1956, by H.F. Shroyer. He patented the use of foam patterns embedded in traditional green sand for metal casting.", "Engineering,_Manufacturing": 0.999971509, "qwen": "Yes"}
{"id": "16988061", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=16988061", "title": "Shear forming", "text": "Shear forming, also referred as shear spinning, is similar to metal spinning. In shear spinning the area of the final piece is approximately equal to that of the flat sheet metal blank. The wall thickness is maintained by controlling the gap between the roller and the mandrel. In shear forming a reduction of the wall thickness occurs.\nBefore the 1950s, spinning was performed on a simple turning lathe. When new technologies were introduced to the field of metal spinning and powered dedicated spinning machines were available, shear forming started its development in Sweden.\nSchematics.\nFigure 2 shows the schematics of a shear forming process.\n1. A sheet metal blank is placed between the mandrel and the chuck of the spinning machine. The mandrel has the interior shape of the desired final component.\n2. A roller makes the sheet metal wrap the mandrel so that it takes its shape.\nAs can be seen, s1 which is the initial wall thickness of the workpiece is reduced to s0.\nWorkpiece and roller tool profiles.\nIn shear forming, the starting workpiece can have circular or rectangular cross sections. On the other hand, the profile shape of the final component can be concave, convex or a combination of these two.\nA shear-forming machine looks very much like a conventional spinning machine, except that it has to be much more robust to withstand the higher forces necessary to perform the shearing operation.\nThe design of the roller must be considered carefully, because it affects the shape of the component, the wall thickness, and dimensional accuracy. The smaller the tool nose radius, the higher the stresses and poorest thickness uniformity achieved.\nSpinnability.\nSpinnability, sometimes referred as shear spinnability, can be defined as the ability of a metal to undergo shear spinning deformation without exceeding its tensile strength and tearing. Published work on spinnability is available from the authors Kegg and Kalpakcioglu.\nKegg predicted that for materials with a tensile reduction of 80%, the limiting spinning reduction will be equal or greater than 80%. \nKalpakciouglu concluded that for metals with a true fracture strain of 0.5 or greater, there is a maximum limit for the shear forming reduction. For materials with a true strain below 0.5, the spinnability depends on the ductility of the material.\nHighly spinnable materials include ductile materials like aluminum and certain steel alloys.\nImportance of shear forming operations in manufacturing.\nShear forming and conventional spinning are being used less than other manufacturing processes such as deep drawing and ironing. Being able to achieve almost any shape, thin sectioned parts, makes spinning a versatile process used widely in the production of lightweight items. Other advantages of shear spinning include the good mechanical properties of the final item and a very good surface finish.\nTypical components produced by mechanically powered spinning machines include rocket nose cones, gas turbine engine and dish aerials.\nFlow forming.\nFlow Forming is an incremental metal-forming technique in which a disk or tube of metal is formed over a mandrel by one or more rollers using tremendous pressure. The roller deforms the workpiece, forcing it against the mandrel, both axially lengthening and radially thinning it. Since the pressure exerted by the roller is highly localized and the material is incrementally formed, often there is a net savings in energy in forming over drawing or ironing processes. However, these savings are often not realized because of the inherent difficulties in predicting the resulting deformation for a given roller path. Flow forming subjects the workpiece to a great deal of friction and deformation. These two factors may heat the workpiece to several hundred degrees if proper cooling fluid is not utilized.\nFlow forming is often used to manufacture automobile wheels and can be used to draw a wheel to net width from a machined blank.\nDuring flow forming, the workpiece is cold worked, changing its mechanical properties, so its strength becomes similar to that of forged metal.\nReferences.\n 3. https://www.pmfind.com/benefits/flowforming-process-benefits-process", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "16999355", "revid": "1169771821", "url": "https://en.wikipedia.org/wiki?curid=16999355", "title": "Ultrasonic machining", "text": "Ultrasonic machining is a subtractive manufacturing process that removes material from the surface of a part through high frequency, low amplitude vibrations of a tool against the material surface in the presence of fine abrasive particles. The tool travels vertically or orthogonal to the surface of the part at amplitudes of 0.05 to 0.125 mm (0.002 to 0.005 in.). The fine abrasive grains are mixed with water to form a slurry that is distributed across the part and the tip of the tool. Typical grain sizes of the abrasive material range from 100 to 1000, where smaller grains (higher grain number) produce smoother surface finishes.\nUltrasonic vibration machining is typically used on brittle materials as well as materials with a high hardness due to the microcracking mechanics.\nProcess.\nAn ultrasonically vibrating machine consists of two major components, an electroacoustic transducer and a sonotrode, attached to an electronic control unit with a cable. The abrasive grains in the slurry now act as a free cutting tool as they strike the workpiece thousands of times per second. An electronic oscillator in the control unit produces an alternating current oscillating at a high frequency, usually between 18 and 40 kHz in the ultrasonic range. The transducer converts the oscillating current to a mechanical vibration. Two types of transducers have been used in ultrasonic machining; either piezoelectric or magnetostrictive: \nThe transducer vibrates the sonotrode at low amplitudes and high frequencies. The sonotrode is usually made of low carbon steel. A constant stream of abrasive slurry flows between the sonotrode and work piece. This flow of slurry allows debris to flow away from the work cutting area. The slurry usually consists of abrasive boron carbide, aluminum oxide or silicon carbide particles in a suspension of water (20 to 60% by volume). The sonotrode removes material from the work piece by abrasion where it contacts it, so the result of machining is to cut a perfect negative of the sonotrode's profile into the work piece. Ultrasonic vibration machining allows extremely complex and non-uniform shapes to be cut into the workpiece with extremely high precision. \nMachining time depends on the workpiece's strength, hardness, porosity and fracture toughness; the slurry's material and particle size; and the amplitude of the sonotrode's vibration. The surface finish of materials after machining depends heavily on hardness and strength, with softer and weaker materials exhibiting smoother surface finishes. The inclusion of microcrack and microcavity features on the materials surface depend highly on the crystallographic orientation of the work piece's grains and the materials fracture toughness.\nMechanics.\nUltrasonic vibration machining physically operates by the mechanism of microchipping or erosion on the work piece's surface. Since the abrasive slurry is kept in motion by high frequency, low amplitude vibrations, the impact forces of the slurry are significant, causing high contact stresses. These high contact stresses are achieved by the small contact area between the slurry's particles and the work piece's surface. Brittle materials fail by cracking mechanics and these high stresses are sufficient to cause micro-scale chips to be removed from its surface. The material as a whole does not fail due to the extremely localized stress regions. The average force imparted by a particle of the slurry impacting the work piece's surface and rebounding can be characterized by the following equation:\nWhere \"m\" is the mass of the particle, \"v\" is the velocity of the particle when striking the surface and \"to\" is the contact time, which can be approximated according to the following equation:\nWhere \"r\" is the radius of the particle, \"co\" is the elastic wave velocity of the work piece, \"E\" is the work pieces Young's Modulus and \"ρ\" is the materials density.\nTypes.\nRotary ultrasonic vibration machining.\nIn rotary ultrasonic vibration machining (RUM), the vertically oscillating tool is able to revolve about the vertical center line of the tool. Instead of using an abrasive slurry to remove material, the surface of the tool is impregnated with diamonds that grind down the surface of the part. Rotary ultrasonic machines are specialized in machining advanced ceramics and alloys such as glass, quartz, structural ceramics, Ti-alloys, alumina, and silicon carbide. Rotary ultrasonic machines are used to produce deep holes with a high level of precision.\nRotary ultrasonic vibration machining is a relatively new manufacturing process that is still being extensively researched. Currently, researchers are trying to adapt this process to the micro level and to allow the machine to operate similar to a milling machine.\nChemical-assisted ultrasonic vibration machining.\nIn chemical-assisted ultrasonic machining (CUSM), a chemically reactive abrasive fluid is used to ensure greater machining of glass and ceramic materials. Using an acidic solution, such as hydrofluoric acid, machining characteristics such as material removal rate and surface quality can be improved greatly compared to traditional ultrasonic machining. While time spent machining and surface roughness decrease with CUSM, the entrance profile diameter is slightly larger than normal due to the additional chemical reactivity of the new slurry choice. In order to limit the extent of this enlargement, the acid content of the slurry must be carefully selected as to ensure user safety and a quality product.\nApplications.\nSince ultrasonic vibration machining does not use subtractive methods that may alter the physical properties of a workpiece, such as thermal, chemical, or electrical processes, it has many useful applications for materials that are more brittle and sensitive than traditional machining metals. Materials that are commonly machined using ultrasonic methods include ceramics, carbides, glass, precious stones and hardened steels. These materials are used in optical and electrical applications where more precise machining methods are required to ensure dimensional accuracy and quality performance of hard and brittle materials. Ultrasonic machining is precise enough to be used in the creation of microelectromechanical system components such as micro-structured glass wafers.\nIn addition to small-scale components, ultrasonic vibration machining is used for structural components because of the required precision and surface quality provided by the method. The process can safely and effectively create shapes out of high-quality single crystal materials that are often necessary but difficult to generate during normal crystal growth. As advanced ceramics become a greater part of the structural engineering realm, ultrasonic machining will continue to provide precise and effective methods of ensuring proper physical dimensions while maintaining crystallographic properties.\nAdvantages.\nUltrasonic vibration machining is a unique non-traditional manufacturing process because it can produce parts with high precision that are made of hard and brittle materials which are often difficult to machine. Additionally, ultrasonic machining is capable of manufacturing fragile materials such as glass and non-conductive metals that can not be machined by alternative methods such as electrical discharge machining and electrochemical machining. Ultrasonic machining is able to produce high-tolerance parts because there is no distortion of the worked material. The absence of distortion is due to no heat generation from the sonotrode against the work piece and is beneficial because the physical properties of the part will remain uniform throughout. Furthermore, no burrs are created in the process, thus fewer operations are required to produce a finished part.\nDisadvantages.\nBecause ultrasonic vibration machining is driven by microchipping or erosion mechanisms, the material removal rate of metals can be slow and the sonotrode tip can wear down quickly from the constant impact of abrasive particles on the tool. Moreover, drilling deep holes in parts can prove difficult as the abrasive slurry will not effectively reach the bottom of the hole. Note, rotary ultrasonic machining is efficient at drilling deep holes in ceramics because the absence of a slurry cutting fluid and the cutting tool is coated in harder diamond abrasives. In addition, ultrasonic vibration machining can only be used on materials with a hardness value of at least 45 HRC.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "17000875", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=17000875", "title": "Grinding (abrasive cutting)", "text": "Grinding is a type of abrasive machining process which uses a grinding wheel as cutting tool.\nA wide variety of machines are used for grinding, best classified as portable or stationary:\nMilling practice is a large and diverse area of manufacturing and toolmaking. It can produce very fine finishes and very accurate dimensions; yet in mass production contexts, it can also rough out large volumes of metal quite rapidly. It is usually better suited to the machining of very hard materials than is \"regular\" machining (that is, cutting larger chips with cutting tools such as tool bits or milling cutters), and until recent decades it was the only practical way to machine such materials as hardened steels. Compared to \"regular\" machining, it is usually better suited to taking very shallow cuts, such as reducing a shaft's diameter by half a thousandth of an inch or 12.7 μm.\nGrinding is a subset of cutting, as grinding is a true metal-cutting process. Each grain of abrasive functions as a microscopic single-point cutting edge (although of high negative rake angle), and shears a tiny chip that is analogous to what would conventionally be called a \"cut\" chip (turning, milling, drilling, tapping, etc.) . However, among people who work in the machining fields, the term \"cutting\" is often understood to refer to the macroscopic cutting operations, and \"grinding\" is often mentally categorized as a \"separate\" process. This is why the terms are usually used separately in shop-floor practice.\nLapping and sanding are subsets of grinding.\nProcesses.\nSelecting which of the following grinding operations to be used is determined by the size, shape, features and the desired production rate.\nCreep-feed grinding.\nCreep-feed grinding (CFG) was a grinding process which was invented in Germany in the late 1950s by Edmund and Gerhard Lang. Normal grinding is used primarily to finish surfaces. But CFG is used for high rates of material removal, competing with milling and turning as a manufacturing process choice. CFG has grinding depth up to 6 mm (0.236 inches) and workpiece speed is low. Surfaces with a softer-grade resin bond are used to keep workpiece temperature low and an improved surface finish up to 1.6 μm Rmax.\nCFG can take 117 s to remove of material. Precision grinding would take more than 200 s to do the same. CFG has the disadvantage of a wheel that is constantly degrading, requires high spindle power , and is limited in the length of part it can machine.\nTo address the problem of wheel sharpness, continuous-dress creep-feed grinding (CDCF) was developed in 1970s. The wheel is dressed constantly during machining in CDCF process and keeps the wheel in a state of specified sharpness. It takes only 17 s to remove of material, a huge gain in productivity. 38 hp (28 kW) spindle power is required, with a low to conventional spindle speeds. The limit on part length was erased.\nHigh-efficiency deep grinding (HEDG) is another type of grinding. This process uses plated superabrasive wheels. These wheels never need dressing and last longer than other wheels. This reduces capital equipment investment costs. HEDG can be used on long part lengths and removes material at a rate of in 83 s. HEDG requires high spindle power and high spindle speeds.\nPeel grinding, patented under the name of Quickpoint in 1985 by Erwin Junker Maschinenfabrik, GmbH in Nordrach, Germany, uses a thin superabrasive grinding disk oriented almost parallel to a cylindrical workpiece and operates somewhat like a lathe turning tool.\nUltra-high speed grinding (UHSG) can run at speeds higher than 40,000 fpm (200 m/s), taking 41 s to remove of material, but is still in the research and development (R&D) stage. It also requires high spindle power and high spindle speeds.\nCylindrical grinding.\nCylindrical grinding (also called center-type grinding) is used to grind the cylindrical surfaces and shoulders of the workpiece. The workpiece is mounted on centers and rotated by a device known as a lathe dog or center driver. The abrasive wheel and the workpiece are rotated by separate motors and at different speeds. The table can be adjusted to produce tapers. The wheel head can be swiveled. The five types of cylindrical grinding are: outside diameter (OD) grinding, inside diameter (ID) grinding, plunge grinding, creep feed grinding, and centerless grinding.\nA cylindrical grinder has a grinding (abrasive) wheel, two centers that hold the workpiece, and a chuck, grinding dog, or other mechanism to drive the work. Most cylindrical grinding machines include a swivel to allow the forming of tapered pieces. The wheel and workpiece move parallel to one another in both the radial and longitudinal directions. The abrasive wheel can have many shapes. Standard disk-shaped wheels can be used to create a tapered or straight workpiece geometry, while formed wheels are used to create a shaped workpiece. The process using a formed wheel creates less vibration than using a regular disk-shaped wheel.\nTolerances for cylindrical grinding are held within ± for diameter and ± for roundness. Precision work can reach tolerances as high as ± for diameter and ± for roundness. Surface finishes can range from to , with typical finishes ranging from .\nSurface grinding.\n\"Surface grinding\" uses a rotating abrasive wheel to remove material, creating a flat surface. The tolerances that are normally achieved with grinding are ± for grinding a flat material and ± for a parallel surface.\nThe surface grinder is composed of an abrasive wheel, a workholding device known as a chuck, either electromagnetic or vacuum, and a reciprocating table.\nGrinding is commonly used on cast iron and various types of steel. These materials lend themselves to grinding because they can be held by the magnetic chuck commonly used on grinding machines and do not melt into the cutting wheel, clogging it and preventing it from cutting. Materials that are less commonly ground are aluminum, stainless steel, brass, and plastics. These all tend to clog the cutting wheel more than steel and cast iron, but with special techniques it is possible to grind them.\nOthers.\nCenterless grinding is when the workpiece is supported by a blade instead of by centers or chucks. Two wheels are used. The larger one is used to grind the surface of the workpiece and the smaller wheel is used to regulate the axial movement of the workpiece. Types of centerless grinding include through-feed grinding, in-feed/plunge grinding, and internal centerless grinding.\nElectrochemical grinding is a type of grinding in which a positively charged workpiece in a conductive fluid is eroded by a negatively charged grinding wheel. The pieces from the workpiece are dissolved into the conductive fluid.\nElectrolytic in-process dressing (ELID) grinding is one of the most accurate grinding methods. In this ultra precision grinding technology the grinding wheel is dressed electrochemically and in-process to maintain the accuracy of the grinding. An ELID cell consists of a metal bonded grinding wheel, a cathode electrode, a pulsed DC power supply and electrolyte. The wheel is connected to the positive terminal of the DC power supply through a carbon brush whereas the electrode is connected to the negative pole of the power supply. Usually alkaline liquids are used as both electrolytes and coolant for grinding. A nozzle is used to inject the electrolyte into the gap between wheel and electrode. The gap is usually maintained to be approximately 0.1mm to 0.3 mm. During the grinding operation one side of the wheel takes part in the grinding operation whereas the other side of the wheel is being dressed by electrochemical reaction. The dissolution of the metallic bond material is caused by the dressing which in turns results continuous protrusion of new sharp grits.\n is a specialized type of cylindrical grinding where the grinding wheel has the exact shape of the final product. The grinding wheel does not traverse the workpiece.\nInternal grinding is used to grind the internal diameter of the workpiece. Tapered holes can be ground with the use of internal grinders that can swivel on the horizontal.\nPre-grinding - When a new tool has been built and has been heat-treated, it is pre-ground before welding or hardfacing commences. This usually involves grinding the outside diameter (OD) slightly higher than the finish grind OD to ensure the correct finish size.\nGrinding wheel.\nA grinding wheel is an expendable wheel used for various grinding and abrasive machining operations. It is generally made from a matrix of coarse abrasive particles pressed and bonded together to form a solid, circular shape, various profiles and cross sections are available depending on the intended usage for the wheel. Grinding wheels may also be made from a solid steel or aluminium disc with particles bonded to the surface.\nLubrication.\nThe use of fluids in a grinding process is often necessary to cool and lubricate the wheel and workpiece as well as remove the chips produced in the grinding process. The most common grinding fluids are water-soluble chemical fluids, water-soluble oils, synthetic oils, and petroleum-based oils. It is imperative that the fluid be applied directly to the cutting area to prevent the fluid being blown away from the piece due to rapid rotation of the wheel.\nThe workpiece.\nWorkholding methods.\nThe workpiece is manually clamped to a lathe dog, powered by the faceplate, that holds the piece in between two centers and rotates the piece. The piece and the grinding wheel rotate in opposite directions and small bits of the piece are removed as it passes along the grinding wheel. In some instances special drive centers may be used to allow the edges to be ground. The workholding method affects the production time as it changes set up times.\nWorkpiece materials.\nTypical workpiece materials include aluminum, brass, plastics, cast iron, mild steel, and stainless steel. Aluminum, brass and plastics can have poor to fair machinability characteristics for cylindrical grinding. Cast Iron and mild steel have very good characteristics for cylindrical grinding. Stainless steel is very difficult to grind due to its toughness and ability to work harden, but can be worked with the right grade of grinding wheels.\nWorkpiece geometry.\nThe final shape of a workpiece is the mirror image of the grinding wheel, with cylindrical wheels creating cylindrical pieces and formed wheels creating formed pieces. Typical sizes on workpieces range from 0.75 in to 20 in (18 mm to 1 m) and 0.80 in to 75 in (2 cm to 4 m) in length, although pieces from 0.25 in to 60 in (6 mm to 1.5 m) in diameter and 0.30 in to 100 in (8 mm to 2.5 m) in length can be ground. Resulting shapes can be straight cylinders, straight-edged conical shapes, or even crankshafts for engines that experience relatively low torque.\nEffects on workpiece materials.\nChemical property changes include an increased susceptibility to corrosion because of high surface stress.\nMechanical properties will change due to stresses put on the part during finishing. High grinding temperatures may cause a thin martensitic layer to form on the part, which will lead to reduced material strength from microcracks.\nPhysical property changes include the possible loss of magnetic properties on ferromagnetic materials.", "Engineering,_Manufacturing": 1.0000025034, "qwen": "Yes"}
{"id": "17015291", "revid": "37982659", "url": "https://en.wikipedia.org/wiki?curid=17015291", "title": "Diffusion hardening", "text": "Diffusion hardening is a process used in manufacturing that increases the hardness of steels. In diffusion hardening, diffusion occurs between a steel with a low carbon content and a carbon-rich environment to increase the carbon content of the steel and ultimately harden the workpiece. Diffusion only happens through a small thickness of a piece of steel (about 2.5 μm to 1.5 mm), so only the surface is hardened while the core maintains its original mechanical properties. Heat treating may be performed on a diffusion hardened part to increase the hardness of the core as desired, but in most cases in which diffusion hardening is performed, it is desirable to have parts with a hard outer shell and a more ductile inside. Heat treating and quenching is a more efficient process if hardness is desired throughout the whole part. In the case of manufacturing parts subject to large amounts of wear, such as gears, the non-uniform properties acquired through diffusion hardening are desired. Through this process, gears obtain a hard wear-resistant outer shell but maintain their softer and more impact-resistant core.\nProcess.\nDiffusion hardening is performed by completely surrounding a metal part with the element to be diffused into it in either the solid, liquid, or gas phase depending on the type of diffusion process being performed. The concentration of the diffusing element surrounding the part must be higher than the concentration of the element inside the part, or diffusion will not occur. The metal and the surrounding element must then be heated to a temperature sufficiently high for diffusion to occur. In the case of pack carburizing, the temperature must be 900 °C and the part must be allowed to sit for 12 to 72 hours for the correct amount of diffusion to occur.\nTypes.\nDiffusion hardening can be done in many different ways to achieve different hardnesses and different surface finishes on metal parts. Some of the different diffusion hardening operations include: Carburizing, Nitriding, Carbonitriding, Nitrocarburizing, Boriding, Titanium-carbon diffusion, and Toyota diffusion. While diffusion hardening is performed mainly on steel parts and carbon is mainly the element used for diffusion, diffusion hardening can also be performed with other diffusion elements and with other metals. In nitriding, nitrogen is diffused into the surface of steel, but can also be used with metals such as Aluminum, Chromium, Molybdenum, and Vanadium. Besides metals and diffusion elements used, diffusion hardening processes differ in the temperature required for diffusion, the phase of the diffusion element, and additional treatments such as quenching and tempering. These different factors greatly affect surface finish and dimensional accuracy of a part. A quenched and tempered part does not have the same dimensional accuracy as a part that has not undergone such a process. Also, they can affect the efficiency of the overall process. In carburizing, the carbon can be in any of the solid, liquid, or gas phases. Although using carbon in the solid phase is usually the safest and easiest of these to work with, the process is difficult to control and the heating is inefficient. All these things must come into consideration when choosing a diffusion hardening process.", "Engineering,_Manufacturing": 1.0000054836, "qwen": "Yes"}
{"id": "17015861", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=17015861", "title": "Structural shape rolling", "text": "Structural shape rolling, also known as shape rolling and profile rolling, is the rolling and roll forming of structural shapes by passing them through a rolling mill to bend or deform the workpiece to a desired shape while maintaining a constant cross-section. Structural shapes that can be made with this metal forming process include I-beams, H-beams, T-beams, U-beams, angle iron, channels, bar stock, and railroad rails. The most commonly rolled material is structural steel, including carbon steel and stainless steel. Other metals, plastic, paper, and glass can also be rolled. Common applications include railroads, bridges, roller coasters, art, and architectural applications.\nIt is a cost-effective way of bending these materials because the process requires less set-up time and uses pre-made dies that are changed according to the shape and dimension of the workpiece. This process can roll workpieces into full circles.\nProcess.\nStructural shape rolling uses profile rolling techniques where the workpiece is passed through a series of flatteners (of larger magnitude than most common rolling devices) that match the workpieces' cross-section. The most common method uses 3 rollers; the bending is controlled by varying the distance between the rollers.\nStructural shapes can be rolled in different ways such as the “easy-way”, the “hard-way”, heel in/out, ball in/out, leg in/out, stem in/out, and off axis. The hard-way would be bending the workpiece in the orientation where its moment of inertia is the greatest. The easy-way is bending the workpiece along the axis with the smallest moment of inertia. For example, a piece of angle iron rolled the easy-way would be rolled along one of its flanges, while the hard-way would be along the angle itself.", "Engineering,_Manufacturing": 0.9999043941, "qwen": "Yes"}
{"id": "44883", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=44883", "title": "Welding", "text": "Welding is a fabrication process that joins materials, usually metals or thermoplastics, by using high heat to melt the parts together and allowing them to cool, causing fusion. Welding is distinct from lower temperature techniques such as brazing and soldering, which do not melt the base metal (parent metal).\nIn addition to melting the base metal, a filler material is typically added to the joint to form a pool of molten material (the weld pool) that cools to form a joint that, based on weld configuration (butt, full penetration, fillet, etc.), can be stronger than the base material. Pressure may also be used in conjunction with heat or by itself to produce a weld. Welding also requires a form of shield to protect the filler metals or melted metals from being contaminated or oxidized.\nMany different energy sources can be used for welding, including a gas flame (chemical), an electric arc (electrical), a laser, an electron beam, friction, and ultrasound. While often an industrial process, welding may be performed in many different environments, including in open air, under water, and in outer space. Welding is a hazardous undertaking and precautions are required to avoid burns, electric shock, vision damage, inhalation of poisonous gases and fumes, and exposure to intense ultraviolet radiation.\nUntil the end of the 19th century, the only welding process was forge welding, which blacksmiths had used for millennia to join iron and steel by heating and hammering. Arc welding and oxy-fuel welding were among the first processes to develop late in the century, and electric resistance welding followed soon after. Welding technology advanced quickly during the early 20th century as world wars drove the demand for reliable and inexpensive joining methods. Following the wars, several modern welding techniques were developed, including manual methods like shielded metal arc welding, now one of the most popular welding methods, as well as semi-automatic and automatic processes such as gas metal arc welding, submerged arc welding, flux-cored arc welding and electroslag welding. Developments continued with the invention of laser beam welding, electron beam welding, magnetic pulse welding, and friction stir welding in the latter half of the century. Today, as the science continues to advance, robot welding is commonplace in industrial settings, and researchers continue to develop new welding methods and gain greater understanding of weld quality.\nEtymology.\nThe term \"weld\" is of English origin, with roots from Scandinavia. It is often confused with the Old English word , meaning 'a forested area', but this word eventually morphed into the modern version, \"wild\". The Old English word for welding iron was ('to bring together') or ('to bring together hot', with \"hot\" more relating to red-hot or a swelling rage; in contrast to , 'to bind together with rope or fasteners'). The term \"weld\" is derived from the Middle English verb \"well\" (; plural/present tense: ) or \"welling\" , meaning 'to heat' (to the maximum temperature possible); 'to bring to a boil'. The modern word was probably derived from the past-tense participle \"welled\" , with the addition of \"d\" for this purpose being common in the Germanic languages of the Angles and Saxons. It was first recorded in English in 1590, from a version of the Christian Bible that was originally translated into English by John Wycliffe in the fourteenth century. The original version, from Isaiah 2:4, reads, \" (they shall beat together their swords into plowshares), while the 1590 version was changed to, \"\"\" (they shall weld together their swords into plowshares), suggesting this particular use of the word probably became popular in English sometime between these periods.\nThe word is derived from the Old Swedish word , meaning 'to boil'. Sweden was a large exporter of iron during the Middle Ages, and many other European languages used different words but with the same meaning to refer to welding iron, such as the Illyrian (Greek) ('to boil'), Turkish ('to boil'), Grison (Swiss) ('to boil'), or the Lettish (Latvian) ('to weld or solder', derived from , 'to boil'). In Swedish, however, the word only referred to joining metals when combined with the word for iron , as in (literally: 'to boil iron'). The word possibly entered English from the Swedish iron trade, or possibly was imported with the thousands of Viking settlements that arrived in England before and during the Viking Age, as more than half of the most common English words in everyday use are Scandinavian in origin.\nHistory.\nThe history of joining metals goes back several millennia. The earliest examples of this come from the Bronze and Iron Ages in Europe and the Middle East. The ancient Greek historian Herodotus states in \"The Histories\" of the 5th century BC that Glaucus of Chios \"was the man who single-handedly invented iron welding\". Welding was used in the construction of the Iron pillar of Delhi, erected in Delhi, India about 310 AD and weighing 5.4 metric tons.\nThe Middle Ages brought advances in forge welding, in which blacksmiths pounded heated metal repeatedly until bonding occurred. In 1540, Vannoccio Biringuccio published \"De la pirotechnia\", which includes descriptions of the forging operation. Renaissance craftsmen were skilled in the process, and the industry continued to grow during the following centuries.\nIn 1800, Sir Humphry Davy discovered the short-pulse electrical arc and presented his results in 1801. In 1802, Russian scientist Vasily Petrov created the continuous electric arc, and subsequently published \"News of Galvanic-Voltaic Experiments\" in 1803, in which he described experiments carried out in 1802. Of great importance in this work was the description of a stable arc discharge and the indication of its possible use for many applications, one being melting metals. In 1808, Davy, who was unaware of Petrov's work, rediscovered the continuous electric arc. In 1881–82 inventors Nikolai Benardos (Russian) and Stanisław Olszewski (Polish) created the first electric arc welding method known as carbon arc welding using carbon electrodes. The advances in arc welding continued with the invention of metal electrodes in the late 1800s by a Russian, Nikolai Slavyanov (1888), and an American, C. L. Coffin (1890). Around 1900, A. P. Strohmenger released a coated metal electrode in Britain, which gave a more stable arc. In 1905, Russian scientist Vladimir Mitkevich proposed using a three-phase electric arc for welding. Alternating current welding was invented by C. J. Holslag in 1919, but did not become popular for another decade.\nResistance welding was also developed during the final decades of the 19th century, with the first patents going to Elihu Thomson in 1885, who produced further advances over the next 15 years. Thermite welding was invented in 1893, and around that time another process, oxyfuel welding, became well established. Acetylene was discovered in 1836 by Edmund Davy, but its use was not practical in welding until about 1900, when a suitable torch was developed. At first, oxyfuel welding was one of the more popular welding methods due to its portability and relatively low cost. As the 20th century progressed, however, it fell out of favor for industrial applications. It was largely replaced with arc welding, as advances in metal coverings (known as flux) were made. Flux covering the electrode primarily shields the base material from impurities, but also stabilizes the arc and can add alloying components to the weld metal.\nWorld War I caused a major surge in the use of welding, with the various military powers attempting to determine which of the several new welding processes would be best. The British primarily used arc welding, even constructing a ship, the \"Fullagar\" with an entirely welded hull. Arc welding was first applied to aircraft during the war as well, as some German airplane fuselages were constructed using the process. Also noteworthy is the first welded road bridge in the world, the Maurzyce Bridge in Poland (1928).\nDuring the 1920s, significant advances were made in welding technology, including the introduction of automatic welding in 1920, in which electrode wire was fed continuously. Shielding gas became a subject receiving much attention, as scientists attempted to protect welds from the effects of oxygen and nitrogen in the atmosphere. Porosity and brittleness were the primary problems, and the solutions that developed included the use of hydrogen, argon, and helium as welding atmospheres. During the following decade, further advances allowed for the welding of reactive metals like aluminum and magnesium. This in conjunction with developments in automatic welding, alternating current, and fluxes fed a major expansion of arc welding during the 1930s and then during World War II. In 1930, the first all-welded merchant vessel, M/S \"Carolinian\", was launched.\nDuring the middle of the century, many new welding methods were invented. In 1930, Kyle Taylor was responsible for the release of stud welding, which soon became popular in shipbuilding and construction. Submerged arc welding was invented the same year and continues to be popular today. In 1932 a Russian, Konstantin Khrenov eventually implemented the first underwater electric arc welding. Gas tungsten arc welding, after decades of development, was finally perfected in 1941, and gas metal arc welding followed in 1948, allowing for fast welding of non-ferrous materials but requiring expensive shielding gases. Shielded metal arc welding was developed during the 1950s, using a flux-coated consumable electrode, and it quickly became the most popular metal arc welding process. In 1957, the flux-cored arc welding process debuted, in which the self-shielded wire electrode could be used with automatic equipment, resulting in greatly increased welding speeds, and that same year, plasma arc welding was invented by Robert Gage. Electroslag welding was introduced in 1958, and it was followed by its cousin, electrogas welding, in 1961. In 1953, the Soviet scientist N. F. Kazakov proposed the diffusion bonding method.\nOther recent developments in welding include the 1958 breakthrough of electron beam welding, making deep and narrow welding possible through the concentrated heat source. Following the invention of the laser in 1960, laser beam welding debuted several decades later, and has proved to be especially useful in high-speed, automated welding. Magnetic pulse welding (MPW) has been industrially used since 1967. Friction stir welding was invented in 1991 by Wayne Thomas at The Welding Institute (TWI, UK) and found high-quality applications all over the world. All of these four new processes continue to be quite expensive due to the high cost of the necessary equipment, and this has limited their applications.\nProcesses.\nGas welding.\nThe most common gas welding process is oxyfuel welding, also known as oxyacetylene welding. It is one of the oldest and most versatile welding processes, but in recent years it has become less popular in industrial applications. It is still widely used for welding pipes and tubes, as well as repair work.\nThe equipment is relatively inexpensive and simple, generally employing the combustion of acetylene in oxygen to produce a welding flame temperature of about 3100 °C (5600 °F). The flame, since it is less concentrated than an electric arc, causes slower weld cooling, which can lead to greater residual stresses and weld distortion, though it eases the welding of high alloy steels. A similar process, generally called oxyfuel cutting, is used to cut metals.\nArc welding.\nThese processes use a welding power supply to create and maintain an electric arc between an electrode and the base material to melt metals at the welding point. They can use either direct current (DC) or alternating current (AC), and consumable or non-consumable electrodes. The welding region is sometimes protected by some type of inert or semi-inert gas, known as a shielding gas, and filler material is sometimes used as well.\nArc welding processes.\nOne of the most common types of arc welding is shielded metal arc welding (SMAW); it is also known as manual metal arc welding (MMAW) or stick welding. Electric current is used to strike an arc between the base material and consumable electrode rod, which is made of filler material (typical steel) and is covered with a flux that protects the weld area from oxidation and contamination by producing carbon dioxide (CO2) gas during the welding process. The electrode core itself acts as filler material, making a separate filler unnecessary.\nThe process is versatile and can be performed with relatively inexpensive equipment, making it well suited to shop jobs and field work. An operator can become reasonably proficient with a modest amount of training and can achieve mastery with experience. Weld times are rather slow, since the consumable electrodes must be frequently replaced and because slag, the residue from the flux, must be chipped away after welding. Furthermore, the process is generally limited to welding ferrous materials, though special electrodes have made possible the welding of cast iron, stainless steel, aluminum, and other metals.\nGas metal arc welding (GMAW), also known as metal inert gas or MIG welding, is a semi-automatic or automatic process that uses a continuous wire feed as an electrode and an inert or semi-inert gas mixture to protect the weld from contamination. Since the electrode is continuous, welding speeds are greater for GMAW than for SMAW.\nA related process, flux-cored arc welding (FCAW), uses similar equipment but uses wire consisting of a steel electrode surrounding a powder fill material. This cored wire is more expensive than the standard solid wire and can generate fumes and/or slag, but it permits even higher welding speed and greater metal penetration.\nGas tungsten arc welding (GTAW), or tungsten inert gas (TIG) welding, is a manual welding process that uses a non-consumable tungsten electrode, an inert or semi-inert gas mixture, and a separate filler material. Especially useful for welding thin materials, this method is characterized by a stable arc and high-quality welds, but it requires significant operator skill and can only be accomplished at relatively low speeds.\nGTAW can be used on nearly all weldable metals, though it is most often applied to stainless steel and light metals. It is often used when quality welds are extremely important, such as in bicycle, aircraft and naval applications. A related process, plasma arc welding, also uses a tungsten electrode but uses plasma gas to make the arc. The arc is more concentrated than the GTAW arc, making transverse control more critical and thus generally restricting the technique to a mechanized process. Because of its stable current, the method can be used on a wider range of material thicknesses than can the GTAW process and it is much faster. It can be applied to all of the same materials as GTAW except magnesium, and automated welding of stainless steel is one important application of the process. A variation of the process is plasma cutting, an efficient steel cutting process.\nSubmerged arc welding (SAW) is a high-productivity welding method in which the arc is struck beneath a covering layer of flux. This increases arc quality since contaminants in the atmosphere are blocked by the flux. The slag that forms on the weld generally comes off by itself, and combined with the use of a continuous wire feed, the weld deposition rate is high. Working conditions are much improved over other arc welding processes, since the flux hides the arc and almost no smoke is produced. The process is commonly used in industry, especially for large products and in the manufacture of welded pressure vessels. Other arc welding processes include atomic hydrogen welding, electroslag welding (ESW), electrogas welding, and stud arc welding. ESW is a highly productive, single-pass welding process for thicker materials between 1 inch (25 mm) and 12 inches (300 mm) in a vertical or close to vertical position.\nArc welding power supplies.\nTo supply the electrical power necessary for arc welding processes, a variety of different power supplies can be used. The most common welding power supplies are constant current power supplies and constant voltage power supplies. In arc welding, the length of the arc is directly related to the voltage, and the amount of heat input is related to the current. Constant current power supplies are most often used for manual welding processes such as gas tungsten arc welding and shielded metal arc welding, because they maintain a relatively constant current even as the voltage varies. This is important because in manual welding, it can be difficult to hold the electrode perfectly steady, and as a result, the arc length and thus voltage tend to fluctuate. Constant voltage power supplies hold the voltage constant and vary the current, and as a result, are most often used for automated welding processes such as gas metal arc welding, flux-cored arc welding, and submerged arc welding. In these processes, arc length is kept constant, since any fluctuation in the distance between the wire and the base material is quickly rectified by a large change in current. For example, if the wire and the base material get too close, the current will rapidly increase, which in turn causes the heat to increase and the tip of the wire to melt, returning it to its original separation distance.\nThe type of current used plays an important role in arc welding. Consumable electrode processes such as shielded metal arc welding and gas metal arc welding generally use direct current, but the electrode can be charged either positively or negatively. In welding, the positively charged anode will have a greater heat concentration, and as a result, changing the polarity of the electrode affects weld properties. If the electrode is positively charged, the base metal will be hotter, increasing weld penetration and welding speed. Alternatively, a negatively charged electrode results in more shallow welds. Non-consumable electrode processes, such as gas tungsten arc welding, can use either type of direct current, as well as alternating current. However, with direct current, because the electrode only creates the arc and does not provide filler material, a positively charged electrode causes shallow welds, while a negatively charged electrode makes deeper welds. Alternating current rapidly moves between these two, resulting in medium-penetration welds. One disadvantage of AC, the fact that the arc must be re-ignited after every zero crossings, has been addressed with the invention of special power units that produce a square wave pattern instead of the normal sine wave, making rapid zero crossings possible and minimizing the effects of the problem.\nResistance welding.\nResistance welding involves the generation of heat by passing current through the resistance caused by the contact between two or more metal surfaces. Small pools of molten metal are formed at the weld area as high current (1,000–100,000 A) is passed through the metal. In general, resistance welding methods are efficient and cause little pollution, but their applications are somewhat limited and the equipment cost can be high.\nSpot welding is a popular resistance welding method used to join overlapping metal sheets of up to 3 mm thick. Two electrodes are simultaneously used to clamp the metal sheets together and to pass current through the sheets. The advantages of the method include efficient energy use, limited workpiece deformation, high production rates, easy automation, and no required filler materials. Weld strength is significantly lower than with other welding methods, making the process suitable for only certain applications. It is used extensively in the automotive industry—ordinary cars can have several thousand spot welds made by industrial robots. A specialized process called shot welding, can be used to spot weld stainless steel.\nLike spot welding, seam welding relies on two electrodes to apply pressure and current to join metal sheets. However, instead of pointed electrodes, wheel-shaped electrodes roll along and often feed the workpiece, making it possible to make long continuous welds. In the past, this process was used in the manufacture of beverage cans, but now its uses are more limited. Other resistance welding methods include butt welding, flash welding, projection welding, and upset welding.\nEnergy beam welding.\nEnergy beam welding methods, namely laser beam welding and electron beam welding, are relatively new processes that have become quite popular in high production applications. The two processes are quite similar, differing most notably in their source of power. Laser beam welding employs a highly focused laser beam, while electron beam welding is done in a vacuum and uses an electron beam. Both have a very high energy density, making deep weld penetration possible and minimizing the size of the weld area. Both processes are extremely fast, and are easily automated, making them highly productive. The primary disadvantages are their very high equipment costs (though these are decreasing) and a susceptibility to thermal cracking. Developments in this area include laser-hybrid welding, which uses principles from both laser beam welding and arc welding for even better weld properties, laser cladding, and x-ray welding.\nSolid-state welding.\nLike the first welding process, forge welding, some modern welding methods do not involve the melting of the materials being joined. One of the most popular, ultrasonic welding, is used to connect thin sheets or wires made of metal or thermoplastic by vibrating them at high frequency and under high pressure. The equipment and methods involved are similar to that of resistance welding, but instead of electric current, vibration provides energy input. Welding metals with this process does not involve melting the materials; instead, the weld is formed by introducing mechanical vibrations horizontally under pressure. When welding plastics, the materials should have similar melting temperatures, and the vibrations are introduced vertically. Ultrasonic welding is commonly used for making electrical connections out of aluminum or copper, and it is also a very common polymer welding process.\nAnother common process, explosion welding, involves the joining of materials by pushing them together under extremely high pressure. The energy from the impact plasticizes the materials, forming a weld, even though only a limited amount of heat is generated. The process is commonly used for welding dissimilar materials, including bonding aluminum to carbon steel in ship hulls and stainless steel or titanium to carbon steel in petrochemical pressure vessels.\nOther solid-state welding processes include friction welding (including friction stir welding and friction stir spot welding), magnetic pulse welding, co-extrusion welding, cold welding, diffusion bonding, exothermic welding, high frequency welding, hot pressure welding, induction welding, and roll bonding.\nGeometry.\nWelds can be geometrically prepared in many different ways. The five basic types of weld joints are the butt joint, lap joint, corner joint, edge joint, and T-joint (a variant of this last is the cruciform joint). Other variations exist as well—for example, double-V preparation joints are characterized by the two pieces of material each tapering to a single center point at one-half their height. Single-U and double-U preparation joints are also fairly common—instead of having straight edges like the single-V and double-V preparation joints, they are curved, forming the shape of a U. Lap joints are also commonly more than two pieces thick—depending on the process used and the thickness of the material, many pieces can be welded together in a lap joint geometry.\nMany welding processes require the use of a particular joint design; for example, resistance spot welding, laser beam welding, and electron beam welding are most frequently performed on lap joints. Other welding methods, like shielded metal arc welding, are extremely versatile and can weld virtually any type of joint. Some processes can also be used to make multipass welds, in which one weld is allowed to cool, and then another weld is performed on top of it. This allows for the welding of thick sections arranged in a single-V preparation joint, for example.\nAfter welding, a number of distinct regions can be identified in the weld area. The weld itself is called the fusion zone—more specifically, it is where the filler metal was laid during the welding process. The properties of the fusion zone depend primarily on the filler metal used, and its compatibility with the base materials. It is surrounded by the heat-affected zone, the area that had its microstructure and properties altered by the weld. These properties depend on the base material's behavior when subjected to heat. The metal in this area is often weaker than both the base material and the fusion zone, and is also where residual stresses are found.\nQuality.\nMany distinct factors influence the strength of welds and the material around them, including the welding method, the amount and concentration of energy input, the weldability of the base material, filler material, and flux material, the design of the joint, and the interactions between all these factors.\nFor example, the factor of welding position influences weld quality, that welding codes & specifications may require testing—both welding procedures and welders—using specified welding positions: 1G (flat), 2G (horizontal), 3G (vertical), 4G (overhead), 5G (horizontal fixed pipe), or 6G (inclined fixed pipe).\nTo test the quality of a weld, either destructive or nondestructive testing methods are commonly used to verify that welds are free of defects, have acceptable levels of residual stresses and distortion, and have acceptable heat-affected zone (HAZ) properties. Types of welding defects include cracks, distortion, gas inclusions (porosity), non-metallic inclusions, lack of fusion, incomplete penetration, lamellar tearing, and undercutting.\nThe metalworking industry has instituted codes and specifications to guide welders, weld inspectors, engineers, managers, and property owners in proper welding technique, design of welds, how to judge the quality of welding procedure specification, how to judge the skill of the person performing the weld, and how to ensure the quality of a welding job. Methods such as visual inspection, radiography, ultrasonic testing, phased-array ultrasonics, dye penetrant inspection, magnetic particle inspection, or industrial computed tomography can help with detection and analysis of certain defects.\nHeat-affected zone.\nThe heat-affected zone (HAZ) is a ring surrounding the weld in which the temperature of the welding process, combined with the stresses of uneven heating and cooling, alters the heat-treatment properties of the alloy. The effects of welding on the material surrounding the weld can be detrimental—depending on the materials used and the heat input of the welding process used, the HAZ can be of varying size and strength. The thermal diffusivity of the base material plays a large role—if the diffusivity is high, the material cooling rate is high and the HAZ is relatively small. Conversely, a low diffusivity leads to slower cooling and a larger HAZ. The amount of heat injected by the welding process plays an important role as well, as processes like oxyacetylene welding have an unconcentrated heat input and increase the size of the HAZ. Processes like laser beam welding give a highly concentrated, limited amount of heat, resulting in a small HAZ. Arc welding falls between these two extremes, with the individual processes varying somewhat in heat input. To calculate the heat input for arc welding procedures, the following formula can be used:\nwhere \"Q\" = heat input (kJ/mm), \"V\" = voltage (V), \"I\" = current (A), and \"S\" = welding speed (mm/min). The efficiency is dependent on the welding process used, with shielded metal arc welding having a value of 0.75, gas metal arc welding and submerged arc welding, 0.9, and gas tungsten arc welding, 0.8. Methods of alleviating the stresses and brittleness created in the HAZ include stress relieving and tempering.\nOne major defect concerning the HAZ would be cracking at the toes , due to the rapid expansion (heating) and contraction (cooling) the material may not have the ability to withstand the stress and could cause cracking, one method the control these stress would be to control the heating and cooling rate, such as pre-heating and post- heating \nLifetime extension with after treatment methods.\nThe durability and life of dynamically loaded, welded steel structures is determined in many cases by the welds, in particular the weld transitions. Through selective treatment of the transitions by grinding (abrasive cutting), shot peening, High-frequency impact treatment, Ultrasonic impact treatment, etc. the durability of many designs increases significantly.\nMetallurgy.\nMost solids used are engineering materials consisting of crystalline solids in which the atoms or ions are arranged in a repetitive geometric pattern which is known as a lattice structure. The only exception is material that is made from glass which is a combination of a supercooled liquid and polymers which are aggregates of large organic molecules.\nCrystalline solids cohesion is obtained by a metallic or chemical bond that is formed between the constituent atoms. Chemical bonds can be grouped into two types consisting of ionic and covalent. To form an ionic bond, either a valence or bonding electron separates from one atom and becomes attached to another atom to form oppositely charged ions. The bonding in the static position is when the ions occupy an equilibrium position where the resulting force between them is zero. When the ions are exerted in tension force, the inter-ionic spacing increases creating an electrostatic attractive force, while a repulsing force under compressive force between the atomic nuclei is dominant.\nCovalent bonding takes place when one of the constituent atoms loses one or more electrons, with the other atom gaining the electrons, resulting in an electron cloud that is shared by the molecule as a whole. In both ionic and covalent bonding the location of the ions and electrons are constrained relative to each other, thereby resulting in the bond being characteristically brittle.\nMetallic bonding can be classified as a type of covalent bonding for which the constituent atoms are of the same type and do not combine with one another to form a chemical bond. Atoms will lose an electron(s) forming an array of positive ions. These electrons are shared by the lattice which makes the electron cluster mobile, as the electrons are free to move as well as the ions. For this, it gives metals their relatively high thermal and electrical conductivity as well as being characteristically ductile.\nThree of the most commonly used crystal lattice structures in metals are the body-centred cubic, face-centred cubic and close-packed hexagonal. Ferritic steel has a body-centred cubic structure and austenitic steel, non-ferrous metals like aluminium, copper and nickel have the face-centred cubic structure.\nDuctility is an important factor in ensuring the integrity of structures by enabling them to sustain local stress concentrations without fracture. In addition, structures are required to be of an acceptable strength, which is related to a material's yield strength. In general, as the yield strength of a material increases, there is a corresponding reduction in fracture toughness.\nA reduction in fracture toughness may also be attributed to the embrittlement effect of impurities, or for body-centred cubic metals, from a reduction in temperature. Metals and in particular steels have a transitional temperature range where above this range the metal has acceptable notch-ductility while below this range the material becomes brittle. Within the range, the materials behavior is unpredictable. The reduction in fracture toughness is accompanied by a change in the fracture appearance. When above the transition, the fracture is primarily due to micro-void coalescence, which results in the fracture appearing fibrous. When the temperatures falls the fracture will show signs of cleavage facets. These two appearances are visible by the naked eye. Brittle fracture in steel plates may appear as chevron markings under the microscope. These arrow-like ridges on the crack surface point towards the origin of the fracture.\nFracture toughness is measured using a notched and pre-cracked rectangular specimen, of which the dimensions are specified in standards, for example ASTM E23. There are other means of estimating or measuring fracture toughness by the following: The Charpy impact test per ASTM A370; The crack-tip opening displacement (CTOD) test per BS 7448–1; The J integral test per ASTM E1820; The Pellini drop-weight test per ASTM E208.\nUnusual conditions.\nWhile many welding applications are done in controlled environments such as factories and repair shops, some welding processes are commonly used in a wide variety of conditions, such as open air, underwater, and vacuums (such as space). In open-air applications, such as construction and outdoors repair, shielded metal arc welding is the most common process. Processes that employ inert gases to protect the weld cannot be readily used in such situations, because unpredictable atmospheric movements can result in a faulty weld. Shielded metal arc welding is also often used in underwater welding in the construction and repair of ships, offshore platforms, and pipelines, but others, such as flux cored arc welding and gas tungsten arc welding, are also common. Welding in space is also possible—it was first attempted in 1969 by Russian cosmonauts during the Soyuz 6 mission, when they performed experiments to test shielded metal arc welding, plasma arc welding, and electron beam welding in a depressurized environment. Further testing of these methods was done in the following decades, and today researchers continue to develop methods for using other welding processes in space, such as laser beam welding, resistance welding, and friction welding. Advances in these areas may be useful for future endeavours similar to the construction of the International Space Station, which could rely on welding for joining in space the parts that were manufactured on Earth.\nSafety issues.\nWelding can be dangerous and unhealthy if the proper precautions are not taken. However, using new technology and proper protection greatly reduces risks of injury and death associated with welding. \nSince many common welding procedures involve an open electric arc or flame, the risk of burns and fire is significant; this is why it is classified as a hot work process. To prevent injury, welders wear personal protective equipment in the form of heavy leather gloves and protective long-sleeve jackets to avoid exposure to extreme heat and flames. Synthetic clothing such as polyester should not be worn since it may burn, causing injury. Additionally, the brightness of the weld area leads to a condition called arc eye or flash burns in which ultraviolet light causes inflammation of the cornea and can burn the retinas of the eyes. Goggles and welding helmets with dark UV-filtering face plates are worn to prevent this exposure. Since the 2000s, some helmets have included a face plate which instantly darkens upon exposure to the intense UV light. To protect bystanders, the welding area is often surrounded with translucent welding curtains. These curtains, made of a polyvinyl chloride plastic film, shield people outside the welding area from the UV light of the electric arc, but cannot replace the filter glass used in helmets.\nWelders are often exposed to dangerous gases and particulate matter. Processes like flux-cored arc welding and shielded metal arc welding produce smoke containing particles of various types of oxides. The size of the particles in question tends to influence the toxicity of the fumes, with smaller particles presenting a greater danger. This is because smaller particles have the ability to cross the blood–brain barrier. Fumes and gases, such as carbon dioxide, ozone, and fumes containing heavy metals, can be dangerous to welders lacking proper ventilation and training. Exposure to manganese welding fumes, for example, even at low levels (<0.2 mg/m3), may lead to neurological problems or to damage to the lungs, liver, kidneys, or central nervous system. Nano particles can become trapped in the alveolar macrophages of the lungs and induce pulmonary fibrosis. The use of compressed gases and flames in many welding processes poses an explosion and fire risk. Some common precautions include limiting the amount of oxygen in the air, and keeping combustible materials away from the workplace.\nCosts and trends.\nAs an industrial process, the cost of welding plays a crucial role in manufacturing decisions. Many different variables affect the total cost, including equipment cost, labor cost, material cost, and energy cost. Depending on the process, equipment cost can vary, from inexpensive for methods like shielded metal arc welding and oxyfuel welding, to extremely expensive for methods like laser beam welding and electron beam welding. Because of their high cost, they are only used in high production operations. Similarly, because automation and robots increase equipment costs, they are only implemented when high production is necessary. Labor cost depends on the deposition rate (the rate of welding), the hourly wage, and the total operation time, including time spent fitting, welding, and handling the part. The cost of materials includes the cost of the base and filler material, and the cost of shielding gases. Finally, energy cost depends on arc time and welding power demand.\nFor manual welding methods, labor costs generally make up the vast majority of the total cost. As a result, many cost-saving measures are focused on minimizing operation time. To do this, welding procedures with high deposition rates can be selected, and weld parameters can be fine-tuned to increase welding speed. Mechanization and automation are often implemented to reduce labor costs, but this frequently increases the cost of equipment and creates additional setup time. Material costs tend to increase when special properties are necessary, and energy costs normally do not amount to more than several percent of the total welding cost.\nIn recent years, in order to minimize labor costs in high production manufacturing, industrial welding has become increasingly more automated, most notably with the use of robots in resistance spot welding (especially in the automotive industry) and in arc welding. In robot welding, mechanized devices both hold the material and perform the weld and at first, spot welding was its most common application, but robotic arc welding increases in popularity as technology advances. Other key areas of research and development include the welding of dissimilar materials (such as steel and aluminum, for example) and new welding processes, such as friction stir, magnetic pulse, conductive heat seam, and laser-hybrid welding. Furthermore, progress is desired in making more specialized methods like laser beam welding practical for more applications, such as in the aerospace and automotive industries. Researchers also hope to better understand the often unpredictable properties of welds, especially microstructure, residual stresses, and a weld's tendency to crack or deform.\nThe trend of accelerating the speed at which welds are performed in the steel erection industry comes at a risk to the integrity of the connection. Without proper fusion to the base materials provided by sufficient arc time on the weld, a project inspector cannot ensure the effective diameter of the puddle weld therefore he or she cannot guarantee the published load capacities unless they witness the actual installation. This method of puddle welding is common in the United States and Canada for attaching steel sheets to bar joist and structural steel members. Regional agencies are responsible for ensuring the proper installation of puddle welding on steel construction sites. Currently there is no standard or weld procedure which can ensure the published holding capacity of any unwitnessed connection, but this is under review by the American Welding Society.\nGlass and plastic welding.\nGlasses and certain types of plastics are commonly welded materials. Unlike metals, which have a specific melting point, glasses and plastics have a melting range, called the glass transition. When heating the solid material past the glass-transition temperature (Tg) into this range, it will generally become softer and more pliable. When it crosses through the range, above the glass-melting temperature (Tm), it will become a very thick, sluggish, viscous liquid, slowly decreasing in viscosity as temperature increases. Typically, this viscous liquid will have very little surface tension compared to metals, becoming a sticky, taffy to honey-like consistency, so welding can usually take place by simply pressing two melted surfaces together. The two liquids will generally mix and join at first contact. Upon cooling through the glass transition, the welded piece will solidify as one solid piece of amorphous material.\nGlass welding.\nGlass welding is a common practice during glassblowing. It is used very often in the construction of lighting, neon signs, flashtubes, scientific equipment, and the manufacture of dishes and other glassware. It is also used during glass casting for joining the halves of glass molds, making items such as bottles and jars. Welding glass is accomplished by heating the glass through the glass transition, turning it into a thick, formable, liquid mass. Heating is usually done with a gas or oxy-gas torch, or a furnace, because the temperatures for melting glass are often quite high. This temperature may vary, depending on the type of glass. For example, lead glass becomes a weldable liquid at around , and can be welded with a simple propane torch. On the other hand, quartz glass (fused silica) must be heated to over , but quickly loses its viscosity and formability if overheated, so an oxyhydrogen torch must be used. Sometimes a tube may be attached to the glass, allowing it to be blown into various shapes, such as bulbs, bottles, or tubes. When two pieces of liquid glass are pressed together, they will usually weld very readily. Welding a handle onto a pitcher can usually be done with relative ease. However, when welding a tube to another tube, a combination of blowing and suction, and pressing and pulling is used to ensure a good seal, to shape the glass, and to keep the surface tension from closing the tube in on itself. Sometimes a filler rod may be used, but usually not.\nBecause glass is very brittle in its solid state, it is often prone to cracking upon heating and cooling, especially if the heating and cooling are uneven. This is because the brittleness of glass does not allow for uneven thermal expansion. Glass that has been welded will usually need to be cooled very slowly and evenly through the glass transition, in a process called annealing, to relieve any internal stresses created by a temperature gradient.\nThere are many types of glass, and it is most common to weld using the same types. Different glasses often have different rates of thermal expansion, which can cause them to crack upon cooling when they contract differently. For instance, quartz has very low thermal expansion, while soda-lime glass has very high thermal expansion. When welding different glasses to each other, it is usually important to closely match their coefficients of thermal expansion, to ensure that cracking does not occur. Also, some glasses will simply not mix with others, so welding between certain types may not be possible.\nGlass can also be welded to metals and ceramics, although with metals the process is usually more adhesion to the surface of the metal rather than a commingling of the two materials. However, certain glasses will typically bond only to certain metals. For example, lead glass bonds readily to copper or molybdenum, but not to aluminum. Tungsten electrodes are often used in lighting but will not bond to quartz glass, so the tungsten is often wetted with molten borosilicate glass, which bonds to both tungsten and quartz. However, care must be taken to ensure that all materials have similar coefficients of thermal expansion to prevent cracking both when the object cools and when it is heated again. Special alloys are often used for this purpose, ensuring that the coefficients of expansion match, and sometimes thin, metallic coatings may be applied to a metal to create a good bond with the glass.\nPlastic welding.\nPlastics are generally divided into two categories, which are \"thermosets\" and \"thermoplastics.\" A thermoset is a plastic in which a chemical reaction sets the molecular bonds after first forming the plastic, and then the bonds cannot be broken again without degrading the plastic. Thermosets cannot be melted, therefore, once a thermoset has set it is impossible to weld it. Examples of thermosets include epoxies, silicone, vulcanized rubber, polyester, and polyurethane.\nThermoplastics, by contrast, form long molecular chains, which are often coiled or intertwined, forming an amorphous structure without any long-range, crystalline order. Some thermoplastics may be fully amorphous, while others have a partially crystalline/partially amorphous structure. Both amorphous and semicrystalline thermoplastics have a glass transition, above which welding can occur, but semicrystallines also have a specific melting point which is above the glass transition. Above this melting point, the viscous liquid will become a free-flowing liquid (see rheological weldability for thermoplastics). Examples of thermoplastics include polyethylene, polypropylene, polystyrene, polyvinylchloride (PVC), and fluoroplastics like Teflon and Spectralon.\nWelding thermoplastic is very similar to welding glass. The plastic first must be cleaned and then heated through the glass transition, turning the weld-interface into a thick, viscous liquid. Two heated interfaces can then be pressed together, allowing the molecules to mix through intermolecular diffusion, joining them as one. Then the plastic is cooled through the glass transition, allowing the weld to solidify. A filler rod may often be used for certain types of joints. The main differences between welding glass and plastic are the types of heating methods, the much lower melting temperatures, and the fact that plastics will burn if overheated. Many different methods have been devised for heating plastic to a weldable temperature without burning it. Ovens or electric heating tools can be used to melt the plastic. Ultrasonic, laser, or friction heating are other methods. Resistive metals may be implanted in the plastic, which respond to induction heating. Some plastics will begin to burn at temperatures lower than their glass transition, so welding can be performed by blowing a heated, inert gas onto the plastic, melting it while, at the same time, shielding it from oxygen.\nMany thermoplastics can also be welded using chemical solvents. When placed in contact with the plastic, the solvent will begin to soften it, bringing the surface into a thick, liquid solution. When two melted surfaces are pressed together, the molecules in the solution mix, joining them as one. Because the solvent can permeate the plastic, the solvent evaporates out through the surface of the plastic, causing the weld to drop out of solution and solidify. A common use for solvent welding is for joining PVC or ABS (acrylonitrile butadiene styrene) pipes during plumbing, or for welding styrene and polystyrene plastics in the construction of models. Solvent welding is especially effective on plastics like PVC which burn at or below their glass transition, but may be ineffective on plastics like Teflon or polyethylene that are resistant to chemical decomposition.", "Engineering,_Manufacturing": 0.9998618364, "qwen": "Yes"}
{"id": "8510311", "revid": "27856083", "url": "https://en.wikipedia.org/wiki?curid=8510311", "title": "Liquid Fidelity", "text": "Liquid Fidelity is a \"microdisplay\" technology applied in high-definition televisions. It incorporates Liquid Crystal on Silicon technology capable of producing true 1080p resolution with two million pixels on a single display chip.\nComponents of Liquid Fidelity technology were originally used in 720p HDTVs produced by Uneed Systems of Korea from 2004-2006.\nTechnology Overview.\nLiquid Crystal on Silicon in general is a sophisticated mix of optical and electrical technologies on one chip. The top layer of the chip is liquid crystal material, the bottom layer is an integrated circuit that drives the liquid crystal, and the surface between the layers is highly reflective. The circuit determines how much light passes through the liquid crystal layer, and the reflected light creates an image on a projection screen.\nLCOS chips with both 720p and 1080p resolution have been developed for HDTVs. Nearly all LCOS chips in mass production have been used in three-chip systems, with one LCOS chip each for red, green and blue light. Sony’s SXRD and JVC’s HD-ILA TVs create images this way. While three-chip systems can produce very good HDTV pictures, they are difficult to align precisely and are expensive. Misalignments can cause visible convergence errors between red, green and blue, particularly along the sides and in the corners of the screen.\nLiquid Fidelity addresses both the alignment and cost problems. Exclusive technology enables Liquid Fidelity to change its brightness much more quickly than ordinary LCOS chips can. This fast response allows the use of one chip and a color wheel, rather than three chips, so red, green and blue alignment is assured at all areas on the screen. Also, by eliminating two of the three LCOS chips and the additional optical components to support them, Liquid Fidelity HDTVs are generally less expensive to manufacture.\nComparison to DLP technology.\nDLP uses MEMS technology, which stands for Micro-Electro-Mechanical Systems. DLP HDTV chips include hundreds of thousands of microscopic mirrors which tilt back and forth, reflecting light which is then projected onto a television screen. While Liquid Fidelity creates an HDTV image by controlling the amount of light reflecting from it, DLP creates an HDTV image by varying the percentage of the time that its mirrors are aimed toward the projection screen.\nThe main advantage of Liquid Fidelity over DLP is that the 1080p Liquid Fidelity chip has over 2 million cells, in an array of 1920 x 1080, for true 1080p pixel resolution. The 1080p DLP chips designed for consumer HDTVs have only half that number of microscopic mirrors, and use yet another mechanism to create 2 pixels from each of those mirrors.\nBy providing a dedicated cell for every pixel, Liquid Fidelity technology provides a sharp, stable picture with smooth, fine texture.", "Engineering,_Manufacturing": 0.9980866909, "qwen": "Yes"}
{"id": "38282825", "revid": "1137215530", "url": "https://en.wikipedia.org/wiki?curid=38282825", "title": "Rolling chassis", "text": "A rolling chassis is the fully-assembled chassis of a motor vehicle (car, truck, bus, or other vehicle) without its bodywork. It is equipped with running gear (engine and drivetrain) and ready for delivery to a coachbuilder to be completed. Historically, bespoke luxury automobiles were finished inside and out to an owner's specifications by a coachbuilder, and specialty vehicles (such as fire engines) were outfitted by firms devoted to that task.\nHeavy vehicles.\nSeparate chassis remain in use for almost all heavy vehicles ranging from pickup trucks to the biggest trucks and commercial passenger carrying vehicles.\nThe rolling chassis is delivered to the commercial body maker, coachbuilder, or bulk transporter on its own wheels, under its own power.\nAutomobiles.\nRolling chassis was a stage of manufacture of every vehicle. Mass produced cars were supplied complete from the factory, but luxury cars like Rolls-Royce were supplied as a chassis from the factory to several bespoke coachbuilders like J Gurney Nutting & Co who would supply a body to the customer's order (or build a car which was sold from their showroom). \nAutomobile construction methods changed when unibody or monocoque combined chassis and body structures gradually replaced chassis.", "Engineering,_Manufacturing": 1.0000042915, "qwen": "Yes"}
{"id": "40747695", "revid": "42774876", "url": "https://en.wikipedia.org/wiki?curid=40747695", "title": "Laser sintering of gold", "text": "Laser sintering of gold is a jewellery manufacturing technique first developed by Towe Norlén and Lena Thorsson.\nLaser sintering of gold starts with gold powder, fine as flour. A laser beam sinters (melts) the gold flour locally in an extremely small point, and any shape may be ‘drawn’ precisely with the laser beam, in three dimensions. When the gold object is finished, it is gently brushed from the leftover gold flour, in much the same way as in an archaeological dig.\nThe result is a gold object of virtually any shape, and with higher quality (greater surface density) gold, than that possible to achieve with casting. Moreover, laser sintering circumvents the weakening and surface-deforming mounting process, because the item of jewellery is manufactured in a single piece. Also, jewellery design may be expanded and individualised, as in principle any shape is possible, which facilitates uniqueness and personalized design.\nExternal links.\nWebsites\nVideos:", "Engineering,_Manufacturing": 0.998539567, "qwen": "Yes"}
{"id": "27714583", "revid": "1139053431", "url": "https://en.wikipedia.org/wiki?curid=27714583", "title": "Contact pad", "text": "Contact pads or bond pads are small, conductive surface areas of a printed circuit board (PCB) or die of an integrated circuit. They are often made of gold, copper, or aluminum and measure mere micrometres wide. Pads are positioned on the edges of die, to facilitate connections without shorting. Contact pads exist to provide a larger surface area for connections to a microchip or PCB, allowing for the input and output of data and power. \nPossible methods of connecting contact pads to a system include soldering, wirebonding, or flip chip mounting.\nContact pads are created alongside a chip's functional structure during the photolithography steps of the fabrication process, and afterwards they are tested. During the test process, contact pads are probed with the needles of a probe card on Automatic Test Equipment in order to check for faults via electrical resistance.", "Engineering,_Manufacturing": 1.0000053644, "qwen": "Yes"}
{"id": "27718879", "revid": "8766034", "url": "https://en.wikipedia.org/wiki?curid=27718879", "title": "Design review", "text": "A design review is a milestone within a product development process whereby a design is evaluated against its requirements in order to verify the outcomes of previous activities and identify issues before committing to—and, if need be, to re-prioritise—further work. The ultimate design review, if successful, therefore triggers the product launch or product release.\nThe conduct of design reviews is compulsory as part of design controls, when developing products in certain regulated contexts such as medical devices.\nBy definition, a review must include persons who are external to the design team.\nContents of a design review.\nIn order to evaluate a design against its requirements, a number of means may be considered, such as:\nTiming of design reviews.\nMost formalised systems engineering processes recognise that the cost of correcting a fault increases as it progresses through the development process. Additional effort spent in the early stages of development to discover and correct errors is therefore likely to be worthwhile. Design reviews are example of such an effort.\nTherefore, a number of design reviews may be carried out, for example to evaluate the design against different sets of criteria (consistency, usability, ease of localisation, environmental) or during various stages of the design process.", "Engineering,_Manufacturing": 0.9988237619, "qwen": "Yes"}
{"id": "27721700", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=27721700", "title": "Industrial computed tomography", "text": "Industrial computed tomography (CT) scanning is any computer-aided tomographic process, usually X-ray computed tomography, that uses irradiation to produce three-dimensional internal and external representations of a scanned object. Industrial CT scanning has been used in many areas of industry for internal inspection of components. Some of the key uses for industrial CT scanning have been flaw detection, failure analysis, metrology, assembly analysis and reverse engineering applications. Just as in medical imaging, industrial imaging includes both nontomographic radiography (industrial radiography) and computed tomographic radiography (computed tomography).\nTypes of scanners.\n\"Line beam scanning\" is the traditional process of industrial CT scanning. X-rays are produced and the beam is collimated to create a line. The X-ray line beam is then translated across the part and data is collected by the detector. The data is then reconstructed to create a 3-D volume rendering of the part.\nIn \"cone beam scanning\", the part to be scanned is placed on a rotary table. As the part rotates, the cone of X-rays produce a large number of 2D images that are collected by the detector. The 2D images are then processed to create a 3D volume rendering of the external and internal geometries of the part.\nHistory.\nIndustrial CT scanning technology was introduced in 1972 with the invention of the CT scanner for medical imaging by Godfrey Hounsfield. The invention earned him a Nobel Prize in medicine, which he shared with Allan McLeod Cormack. Many advances in CT scanning have allowed for its use in the industrial field for metrology in addition to the visual inspection primarily used in the medical field (medical CT scan).\nAnalysis and inspection techniques.\nVarious inspection uses and techniques include part-to-CAD comparisons, part-to-part comparisons, assembly and defect analysis, void analysis, wall thickness analysis, and generation of CAD data. The CAD data can be used for reverse engineering, geometric dimensioning and tolerance analysis, and production part approval.\nAssembly.\nOne of the most recognized forms of analysis using CT is for assembly, or visual analysis. CT scanning provides views inside components in their functioning position, without disassembly. Some software programs for industrial CT scanning allow for measurements to be taken from the CT dataset volume rendering. These measurements are useful for determining the clearances between assembled parts or the dimension of an individual feature.\nVoid, crack and defect detection.\nTraditionally, determining defects, voids and cracks within an object would require destructive testing. CT scanning can detect internal features and flaws displaying this information in 3D without destroying the part. Industrial CT scanning (3D X-ray) is used to detect flaws inside a part such as porosity, an inclusion, or a crack. It has been also used to detect the origin and propagation of damages in concrete.\nMetal casting and moulded plastic components are typically prone to porosity because of cooling processes, transitions between thick and thin walls, and material properties. Void analysis can be used to locate, measure, and analyze voids inside plastic or metal components.\nGeometric dimensioning and tolerancing analysis.\nTraditionally, without destructive testing, full metrology has only been performed on the exterior dimensions of components, such as with a coordinate-measuring machine (CMM) or with a vision system to map exterior surfaces. Internal inspection methods would require using a 2D X-ray of the component or the use of destructive testing. Industrial CT scanning allows for full non-destructive metrology. With unlimited geometrical complexity, 3D printing allows for complex internal features to be created with no impact on cost, such features are not accessible using traditional CMM. The first 3D printed artefact that is optimised for characterisation of form using computed tomography CT \nImage-based finite element methods.\nImage-based finite element method converts the 3D image data from X-ray computed tomography directly into meshes for finite element analysis. Benefits of this method include modelling complex geometries (e.g. composite materials) or accurately modelling \"as manufactured\" components at the micro-scale.", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "17549172", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=17549172", "title": "Burnishing (metal)", "text": "Burnishing is the plastic deformation of a surface due to sliding contact with another object. It smooths the surface and makes it shinier. Burnishing may occur on any sliding surface if the contact stress locally exceeds the yield strength of the material. The phenomenon can occur both unintentionally as a failure mode, and intentionally as part of a metalworking or manufacturing process. It is a squeezing operation under cold working.\nFailure mode (unintentionally).\nThe action of a hardened ball against a softer, flat plate illustrates the process of burnishing. If the ball is pushed directly into the plate, stresses develop in both objects around the area where they contact. As this normal force increases, both the ball and the plate's surfaces deform.\nThe deformation caused by the hardened ball increases with the magnitude of the force pressing against it. If the force on it is small, when the force is released both the ball and plate's surface will return to their original, undeformed shape. In that case, the stresses in the plate are always less than the yield strength of the material, so the deformation is purely elastic. Since it was given that the flat plate is softer than the ball, the plate's surface will always deform more.\nIf a larger force is used, there will also be plastic deformation and the plate's surface will be permanently altered. A bowl-shaped indentation will be left behind, surrounded by a ring of raised material that was displaced by the ball. The stresses between the ball and the plate are described in more detail by Hertzian stress theory.\nDragging the ball across the plate will have a different effect than pressing. In that case, the force on the ball can be decomposed into two component forces: one normal to the plate's surface, pressing it in, and the other tangential, dragging it along. As the tangential component is increased, the ball will start to slide along the plate. At the same time, the normal force will deform both objects, just as with the static situation. If the normal force is low, the ball will rub against the plate but not permanently alter its surface. The rubbing action will create friction and heat, but it will not leave a mark on the plate. However, as the normal force increases, eventually the stresses in the plate's surface will exceed its yield strength. When this happens the ball will plow through the surface and create a trough behind it. The plowing action of the ball is burnishing. Burnishing also occurs when the ball can rotate, as would happen in the above scenario if another flat plate was brought down from above to induce downwards loading, and at the same time to cause rotation and translation of the ball, or in the case of a ball bearing.\nBurnishing also occurs on surfaces that conform to each other, such as between two flat plates, but it happens on a microscopic scale. Even the smoothest of surfaces will have imperfections if viewed at a high enough magnification. The imperfections that extend above the general form of a surface are called asperities, and they can plow material on another surface just like the ball dragging along the plate. The combined effect of many of these asperities produce the smeared texture that is associated with burnishing.\nEffects on sliding contact.\nBurnishing is normally undesirable in mechanical components for a variety of reasons, sometimes simply because its effects are unpredictable. Even light burnishing will significantly alter the surface finish of a part. Initially the finish will be smoother, but with repetitive sliding action, grooves will develop on the surface along the sliding direction. The plastic deformation associated with burnishing will harden the surface and generate compressive residual stresses. Although these properties are usually advantageous, excessive burnishing leads to sub-surface cracks which cause spalling, a phenomenon where the upper layer of a surface flakes off of the bulk material.\nBurnishing may also affect the \"performance of a machine\". The plastic deformation associated with burnishing creates greater heat and friction than from rubbing alone. This reduces the efficiency of the machine and limits its speed. Furthermore, plastic deformation alters the form and geometry of the part. This reduces the precision and accuracy of the machine. The combination of higher friction and degraded form often leads to a runaway situation that continually worsens until the component fails.\nTo prevent destructive burnishing, sliding must be avoided, and in rolling situations, loads must be beneath the spalling threshold. In the areas of a machine that slide with respect to each other, roller bearings can be inserted so that the components are in rolling contact instead of sliding. If sliding cannot be avoided, then a lubricant should be added between the components. The purpose of the lubricant in this case is to separate the components with a lubricant film so they cannot contact. The lubricant also distributes the load over a larger area, so that the local contact forces are not as high. If there was already a lubricant, its film thickness must be increased; usually this can be accomplished by increasing the viscosity of the lubricant.\nIn manufacturing (intentionally).\nBurnishing is not always unwanted. If it occurs in a controlled manner, it can have desirable effects. Burnishing processes are used in manufacturing to improve the size, shape, surface finish, or surface hardness of a workpiece. It is essentially a forming operation that occurs on a small scale. The benefits of burnishing often include combatting fatigue failure, preventing corrosion and stress corrosion, texturing surfaces to eliminate visual defects, closing porosity, creating surface compressive residual stress.\nThere are several forms of burnishing processes, the most common are roller burnishing and ball burnishing (a subset of which is also referred to as ballizing). In both cases, a burnishing tool runs against the workpiece and plastically deforms its surface. In some instances of the latter case (and always in ballizing), it rubs, in the former it generally rotates and rolls. The workpiece may be at ambient temperature, or heated to reduce the forces and wear on the tool. The tool is usually hardened and coated with special materials to increase its life.\nBall burnishing, or ballizing, is a replacement for other bore finishing operations such as grinding, honing, or polishing. A ballizing tool consists of one or more over-sized balls that are pushed through a hole. The tool is similar to a broach, but instead of cutting away material, it plows it out of the way.\nBall burnishing is also used as a deburring operation. It is especially useful for removing the burr in the middle of a through hole that was drilled from both sides.\nBall burnishing tools of another type are sometimes used in CNC milling centres to follow a ball-nosed milling operation: the hardened ball is applied along a zig-zag toolpath in a holder similar to a ball-point pen, except that the 'ink' is pressurised, recycled lubricant. This combines the productivity of a machined finish which is achieved by a 'semi-finishing' cut, with a better finish than obtainable with slow and time-consuming finish cuts. The feed rate for burnishing is that associated with 'rapid traverse' rather than finish machining.\nRoller burnishing, or surface rolling, is used on cylindrical, conical, or disk shaped workpieces. The tool resembles a roller bearing, but the rollers are generally very slightly tapered so that their envelope diameter can be accurately adjusted. The rollers typically rotate within a cage, as in a roller bearing. Typical applications for roller burnishing include hydraulic system components, shaft fillets, and sealing surfaces.\nVery close control of size can be exercised.\nBurnishing also occurs to some extent in machining processes. In turning, burnishing occurs if the cutting tool is not sharp, if a large negative rake angle is used, if a very small depth of cut is used, or if the workpiece material is gummy. As a cutting tool wears, it becomes more blunt and the burnishing effect becomes more pronounced. In grinding, since the abrasive grains are randomly oriented and some are not sharp, there is always some amount of burnishing. This is one reason the grinding is less efficient and generates more heat than turning. In drilling, burnishing occurs with drills that have lands to burnish the material as it drills into it. Regular twist drills or straight fluted drills have 2 lands to guide them through the hole. On burnishing drills there are 4 or more lands, similar to reamers.\nBurnish setting, also known as flush, gypsy, or shot setting, is a setting technique used in stonesetting. A space is drilled, into which a stone is inserted such that the girdle of the stone, the point of maximum diameter, is just below the surface of the metal. A burnishing tool is used to push metal all around the stone to hold the stone and give a flush appearance, with a burnished edge around it. This type of setting has a long history but is gaining a resurgence in contemporary jewelry.", "Engineering,_Manufacturing": 0.9999755621, "qwen": "Yes"}
{"id": "12206504", "revid": "107192", "url": "https://en.wikipedia.org/wiki?curid=12206504", "title": "Backgauge", "text": "A backgauge is a mechanical system, normally attached to a brake press. Its main function is to interface with the brake press computer numerical control (CNC), moving along several different axes in order to precisely position a piece of metal for forming.\nBackgauges typically have anywhere from 1 to 6 axes of movement. Each of these individual axes is controlled by a separate electric motor. Often a brake press is sold to a customer in conjunction with a backgauge.\nOn an extrusion saw, a backgauge is responsible for feeding material at exact amounts past a saw blade. It is responsible for the accuracy of the piece's cut length.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "2853363", "revid": "11344827", "url": "https://en.wikipedia.org/wiki?curid=2853363", "title": "Foundry", "text": "A foundry is a factory that produces metal castings. Metals are cast into shapes by melting them into a liquid, pouring the metal into a mold, and removing the mold material after the metal has solidified as it cools. The most common metals processed are aluminum and cast iron. However, other metals, such as bronze, brass, steel, magnesium, and zinc, are also used to produce castings in foundries. In this process, parts of desired shapes and sizes can be formed.\nFoundries are one of the largest contributors to the manufacturing recycling movement, melting and recasting millions of tons of scrap metal every year to create new durable goods. Moreover, many foundries use sand in their molding process. These foundries often use, recondition, and reuse sand, which is another form of recycling.\nProcess.\nIn metalworking, casting involves pouring liquid metal into a mold, which contains a hollow cavity of the desired shape, and then allowing it to cool and solidify. The solidified part is also known as a casting, which is ejected or broken out of the mold to complete the process. Casting is most often used for making complex shapes that would be difficult or uneconomical to make by other methods.\nMelting.\nMelting is performed in a furnace. Virgin material, external scrap, internal scrap, and alloying elements are used to charge the furnace. Virgin material refers to commercially pure forms of the primary metal used to form a particular alloy. Alloying elements are either pure forms of an alloying element, like electrolytic nickel, or alloys of limited composition, such as ferroalloys or master alloys. External scrap is material from other forming processes such as punching, forging, or machining. Internal scrap consists of gates, risers, defective castings, and other extraneous metal oddments produced within the facility.\nThe process includes melting the charge, refining the melt, adjusting the melt chemistry and tapping into a transport vessel. Refining is done to remove harmful gases and elements from the molten metal to avoid casting defects. Material is added during the melting process to bring the final chemistry within a specific range specified by industry and/or internal standards. Certain fluxes may be used to separate the metal from slag and/or dross and degassers are used to remove dissolved gas from metals that readily dissolve in gasses. During the tap, final chemistry adjustments are made.\nFurnace.\nSeveral specialised furnaces are used to heat the metal. Furnaces are refractory-lined vessels that contain the material to be melted and provide the energy to melt it. Modern furnace types include electric arc furnaces (EAF), induction furnaces, cupolas, reverberatory, and crucible furnaces. Furnace choice is dependent on the alloy system quantities produced. For ferrous materials EAFs, cupolas, and induction furnaces are commonly used. Reverberatory and crucible furnaces are common for producing aluminium, bronze, and brass castings.\nFurnace design is a complex process, and the design can be optimized based on multiple factors. Furnaces in foundries can be any size, ranging from small ones used to melt precious metals to furnaces weighing several tons, designed to melt hundreds of pounds of scrap at one time. They are designed according to the type of metals that are to be melted. Furnaces must also be designed based on the fuel being used to produce the desired temperature. For low temperature melting point alloys, such as zinc or tin, melting furnaces may reach around . Electricity, propane, or natural gas are usually used to achieve these temperatures. For high melting point alloys such as steel or nickel-based alloys, the furnace must be designed for temperatures over . The fuel used to reach these high temperatures can be electricity (as employed in electric arc furnaces) or coke.\nThe majority of foundries specialize in a particular metal and have furnaces dedicated to these metals. For example, an iron foundry (for cast iron) may use a cupola, induction furnace, or EAF, while a steel foundry will use an EAF or induction furnace. Bronze or brass foundries use crucible furnaces or induction furnaces. Most aluminium foundries use either electric resistance or gas heated crucible furnaces or reverberatory furnaces.\nDegassing.\nDegassing is a process that may be required to reduce the amount of hydrogen present in a batch of molten metal. Gases can form in metal castings in one of two ways:\nHydrogen is a common contaminant for most cast metals. It forms as a result of material reactions or from water vapor or machine lubricants. If the hydrogen concentration in the melt is too high, the resulting casting will be porous; the hydrogen will exit the molten solution, leaving minuscule air pockets, as the metal cools and solidifies. Porosity often seriously deteriorates the mechanical properties of the metal.\nAn efficient way of removing hydrogen from the melt is to bubble a dry, insoluble gas through the melt by purging or agitation. When the bubbles go up in the melt, they catch the dissolved hydrogen and bring it to the surface. Chlorine, nitrogen, helium and argon are often used to degas non-ferrous metals. Carbon monoxide is typically used for iron and steel.\nThere are various types of equipment that can measure the presence of hydrogen. Alternatively, the presence of hydrogen can be measured by determining the density of a metal sample.\nIn cases where porosity still remains present after the degassing process, porosity sealing can be accomplished through a process called metal impregnating.\nMold making.\nIn the casting process, a pattern is made in the shape of the desired part. Simple designs can be made in a single piece or solid pattern. More complex designs are made in two parts, called split patterns. A split pattern has a top or upper section, called a cope, and a bottom or lower section called a drag. Both solid and split patterns can have cores inserted to complete the final part shape. Cores are used to create hollow areas in the mold that would otherwise be impossible to achieve. Where the cope and drag separates is called the parting line.\nWhen making a pattern it is best to taper the edges so that the pattern can be removed without breaking the mold. This is called draft. The opposite of draft is an undercut where there is part of the pattern under the mold material, making it impossible to remove the pattern without damaging the mold.\nThe pattern is made of wax, wood, plastic, or metal. The molds are constructed by several different processes dependent upon the type of foundry, metal to be poured, quantity of parts to be produced, size of the casting, and complexity of the casting. These mold processes include:\nPouring.\nIn a foundry, molten metal is poured into molds. Pouring can be accomplished with gravity, or it may be assisted with a vacuum or pressurized gas. Many modern foundries use robots or automatic pouring machines to pour molten metal. Traditionally, molds were poured by hand using ladles.\nShakeout.\nThe solidified metal component is then removed from its mold. Where the mold is sand based, this can be done by shaking or tumbling. This frees the casting from the sand, which is still attached to the metal runners and gates — which are the channels through which the molten metal traveled to reach the component itself.\nDegating.\nDegating is the removal of the heads, runners, gates, and risers from the casting. Runners, gates, and risers may be removed using cutting torches, bandsaws, or ceramic cutoff blades. For some metal types, and with some gating system designs, the sprue, runners, and gates can be removed by breaking them away from the casting with a sledge hammer or specially designed knockout machinery. Risers must usually be removed using a cutting method (see above) but some newer methods of riser removal use knockoff machinery with special designs incorporated into the riser neck geometry that allow the riser to break off at the right place.\nThe gating system required to produce castings in a mold yields leftover metal — including heads, risers, and sprue (sometimes collectively called sprue) — that can exceed 50% of the metal required to pour a full mold. Since this metal must be remelted as salvage, the yield of a particular gating configuration becomes an important economic consideration when designing various gating schemes, to minimize the cost of excess sprue, and thus overall melting costs.\nHeat treating.\nHeat treating is a group of industrial and metalworking processes used to alter the physical, and sometimes chemical, properties of a material. The most common application is metallurgical. Heat treatments are also used in the manufacture of many other materials, such as glass. Heat treatment involves the use of heating or chilling, normally to extreme temperatures, to achieve a desired result such as hardening or softening of a material. Heat treatment techniques include annealing, case-hardening, precipitation strengthening, tempering, and quenching. Although the term \"heat treatment\" applies only to processes where the heating and cooling are done for the specific purpose of altering properties intentionally, heating and cooling often occur incidentally during other manufacturing processes such as hot forming or welding.\nSurface cleaning.\nAfter degating and heat treating, sand or other molding media may remain adhered to the casting. To remove any mold remnants, the surface is cleaned using a blasting process. This means a granular media will be propelled against the surface of the casting to mechanically knock away the adhering sand. The media may be blown with compressed air, or may be hurled using a shot wheel. The cleaning media strikes the casting surface at high velocity to dislodge the mold remnants (for example, sand, slag) from the casting surface. Numerous materials may be used to clean cast surfaces, including steel, iron, other metal alloys, aluminium oxides, glass beads, walnut shells, baking powder, and many others. The blasting media is selected to develop the color and reflectance of the cast surface. Terms used to describe this process include cleaning, bead blasting, and sand blasting. Shot peening may be used to further work-harden and finish the surface.\nFinishing.\nThe final step in the process of casting usually involves grinding, sanding, or machining the component in order to achieve the desired dimensional accuracies, physical shape, and surface finish.\nRemoving the remaining gate material, called a gate stub, is usually done using a grinder or sander. These processes are used because their material removal rates are slow enough to control the amount of material being removed. These steps are done prior to any final machining.\nAfter grinding, any surfaces that require tight dimensional control are machined. Many castings are machined in CNC milling centers. The reason for this is that these processes have better dimensional capability and repeatability than many casting processes. However, it is not uncommon today for castings to be used without machining.\nA few foundries provide other services before shipping cast products to their customers. It is common to paint castings to prevent corrosion and improve visual appeal. Some foundries assemble castings into complete machines or sub-assemblies. Other foundries weld multiple castings or wrought metals together to form a finished product.\nMore and more, finishing processes are being performed by robotic machines, which eliminate the need for a human to physically grind or break parting lines, gating material, or feeders. Machines can reduce risk of injury to workers and lower costs for consumables — while also increasing productivity. They also limit the potential for human error and increase repeatability in the quality of grinding.", "Engineering,_Manufacturing": 1.0000066757, "qwen": "Yes"}
{"id": "2863774", "revid": "33011235", "url": "https://en.wikipedia.org/wiki?curid=2863774", "title": "Assembly modelling", "text": "Assembly modeling is a technology and method used by computer-aided design and product visualization computer software systems to handle multiple files that represent components within a product. The components within an assembly are represented as solid or surface models.\nOverview.\nThe designer generally has access to models that others are working on concurrently. For example, several people may be designing one machine that has many parts. New parts are added to an assembly model as they are created. Each designer has access to the assembly model, while a work in progress, and while working in their own parts. The design evolution is visible to everyone involved. Depending on the system, it might be necessary for the users to acquire the latest versions saved of each individual components to update the assembly.\nThe individual data files describing the 3D geometry of individual components are assembled together through a number of sub-assembly levels to create an assembly describing the whole product. All CAD and CPD systems support this form of bottom-up construction. Some systems, via associative copying of geometry between components also allow top-down method of design.\nComponents can be positioned within the product assembly using absolute coordinate placement methods or by means of mating conditions. Mating conditions are definitions of the relative position of components between each other; for example alignment of axis of two holes or distance of two faces from one another. The final position of all components based on these relationships is calculated using a geometry constraint engine built into the CAD or visualization package.\nThe importance of assembly modeling in achieving the full benefits of PLM has led to ongoing advances in this technology. These include the use of lightweight data structures such as JT that allow visualization of and interaction with large amounts of product data, direct interface to between Digital Mock ups and PDM systems and active digital mock up technology that unites the ability to visualize the assembly mock up with the ability to measure, analyze, simulate, design and redesign.", "Engineering,_Manufacturing": 0.9999294281, "qwen": "Yes"}
{"id": "2583670", "revid": "14013403", "url": "https://en.wikipedia.org/wiki?curid=2583670", "title": "Wiggler (tool)", "text": "A wiggler, also known as a wobbler, edge-finder, center-finder or laser-centering-device, is a tool used with a machine like a mill, to accurately align the machine head with the work prior to machining.\nEdge finder.\nAn edge finder is a rotating tool, meaning the machine spindle must be turning for the tool to work. On one end of a cylindrical shank, a second cylinder is attached by a spring running through the center of both cylinders. The second cylinder rotates with the first. The axes of the two cylinders are always parallel, but the mating faces are able to slide against each other. Thus the second cylinder can rotate about a different, but always parallel axis to the first. \nAs the second cylinder approaches the edge to be located, it is pushed into alignment with the first. When the horizontal distance from the workpiece to the axis of the shank is exactly equal to the radius of the second cylinder, the second cylinder turns perfectly coaxially with the shank. Even a very small displacement in the direction of the workpiece cause the second cylinder to \"kick off\" and displace dramatically along the workpiece edge. \nOn the other end, a cone shape is also spring-loaded and is used to locate the center of a previously drilled hole. This style of edge finder is considered to be the most accurate, and its accuracy can be further improved through the use of a collet. In proper setups, a repeatability of or better can be obtained.\nElectronic edge finder.\nAn electronic edge finder, is an instrument that can locate edges of work pieces and also height offsets. It works in a non-rotating spindle, which is a great advantage over its mechanical counterparts. It is battery-operated and works by lighting up its internal LED (usually red) when the electrical circuit formed by the instrument, the workpiece and the machine is closed. The light is thus illuminated when the edge finder is touching the workpiece and is visible through openings in the case. A repeatability of can be obtained.\nCenter finder.\nA center finder is a tool used to align the machining center to a precision location on a work piece. Often these locations might be marked using a layout method (coating the surface with layout stain and scribing a precise location with the intersection of the two lines identifying the position to be machined, etc. Sometimes a magnifying glass is used to assist in marking the location. One drawback of this method is that it is only as accurate as the lines that are drawn on the part.). \nIn contrast to the edge finder, in the mechanical versions, the tip is not spring-loaded, and it works with the spindle stopped. In laser versions, an 'X' of light is often projected from the machining center onto the work piece and the work piece location is adjusted to align with the intersection of these lines. In contrast to centering devices, the center finder cannot directly find the center of a work piece, thus requires additional calculation, measurement and/or layout method to align to.\nCentering device.\nA centering device is a tool used to accurately adjust and align the center plane or axis of a work piece or work piece feature to the machining center. In contrast to the edge finder, it most often requires no calculation, measurements or layout method markings to allow this alignment. Mechanical versions may work with the spindle stopped. Laser centering devices can be used to cast patterns of light which, depending on angle of the laser, can achieve a high degree of precision.", "Engineering,_Manufacturing": 0.9999918938, "qwen": "Yes"}
{"id": "2588297", "revid": "1159774573", "url": "https://en.wikipedia.org/wiki?curid=2588297", "title": "Near net shape", "text": "Near-net-shape is an industrial manufacturing technique. As the name implies, the initial production of the item is very close to the final, or \"net\", shape. This reduces the need for surface finishing. By minimizing the use of finishing methods like machining or grinding, near-net-shape production eliminates more than two-thirds of the production costs in some industries.\nProcesses.\nThe following are various near-net-shape processes categorized by material.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "2588632", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=2588632", "title": "Tipped tool", "text": "A tipped tool is any cutting tool in which the cutting edge consists of a separate piece of material that is brazed, welded, or clamped onto a body made of another material. In the types in which the cutter portion is an indexable part clamped by a screw, the cutters are called inserts (because they are inserted into the tool body). Tipped tools allow each part of the tool, the shank and the cutter(s), to be made of the material with the best properties for its job. Common materials for the cutters (brazed tips or clamped inserts) include cemented carbide, polycrystalline diamond, and cubic boron nitride. Tools that are commonly tipped include milling cutters (such as end mills, face mills, and fly cutters), tool bits, router bits, and saw blades (especially the metal-cutting ones).\nAdvantages and disadvantages.\nThe advantage of tipped tools is only a small insert of the cutting material is needed to provide the cutting ability. The small size makes manufacturing of the insert easier than making a solid tool of the same material. This also reduces cost because the tool holder can be made of a less-expensive and tougher material. In some situations a tipped tool is better than its solid counterpart because it combines the toughness of the tool holder with the hardness of the insert.\nIn other situations this is less than optimal, because the joint between the tool holder and the insert reduces rigidity. However, these tools may still be used because the overall cost savings is still greater.\nIn industry today, insert tools are perhaps slightly more common than solid tools, but solid tools are still used in many applications. Entire catalogs of solid–high-speed steel (HSS) and solid-carbide end mills, for example, play prominent parts in some areas of milling practice, including diesinking, moldmaking, and aerospace job or batch production. Most machine shops with lathes have many solid-HSS and solid-carbide tool bits as well as many insert-tipped tool bits, and most commercial operations that involve routers (such as cabinetry and furniture shops) use plenty of solid-HSS and solid-carbide router bits as well as some tipped bits. \nIndexable inserts.\nInserts are removable cutting tips, which means they are not brazed or welded to the tool body. They are usually indexable, meaning that they can be exchanged, and often also rotated or flipped, without disturbing the overall geometry of the tool (effective diameter, tool length offset, etc.). This saves time in manufacturing by allowing fresh cutting edges to be presented periodically without the need for tool grinding, setup changes, or entering of new values into a CNC program.\nWiper insert.\nA \"wiper insert\" is an insert used in a milling machine or a lathe. It is designed for finished cutting, to give a smooth surface on the surface being cut. It uses special geometry to give a good finish on the workpiece at a higher-than-normal feedrate. Wiper inserts generally have a larger area in contact with the workpiece, so they exert higher force on the workpiece. This makes them unsuitable for fragile workpieces.\nISO insert coding.\n\"Inserts used for turning and milling\" are often numbered according to ISO standard 1832. This standard aims to make the naming, specifying and ordering of inserts a simple, consistent and traceable process. This standard takes into account both metric and imperial systems of units, although certain elements differ for each unit system. The code consists of up to 13 symbols with the first 12 of them being compulsory for inserts composed of cubic boron or poly-crystalline diamond and the first 7 being compulsory for all other types of composition.", "Engineering,_Manufacturing": 0.9999976158, "qwen": "Yes"}
{"id": "2590325", "revid": "13172479", "url": "https://en.wikipedia.org/wiki?curid=2590325", "title": "List scheduling", "text": "List scheduling is a greedy algorithm for Identical-machines scheduling. The input to this algorithm is a list of jobs that should be executed on a set of \"m\" machines. The list is ordered in a fixed order, which can be determined e.g. by the priority of executing the jobs, or by their order of arrival. The algorithm repeatedly executes the following steps until a valid schedule is obtained:\nExample.\nSuppose there are five jobs with processing-times {4,5,6,7,8}, and \"m\"=2 processors. Then, the resulting schedule is {4,6,8}, {5,7}, and the makespan is max(18,12)=18; if \"m\"=3, then the resulting schedule is {4,7}, {5,8}, {6}, and the makespan is max(11,13,6)=13.\nPerformance guarantee.\nThe algorithm runs in time formula_1, where \"n\" is the number of jobs. The algorithm always returns a partition of the jobs whose makespan is at most formula_2 times the optimal makespan. This is due to the fact that both the length of the longest job and the average length of all jobs are lower bounds for the optimal makespan. The algorithm can be used as an online algorithm, when the order in which the items arrive cannot be controlled.\nOrdering strategies.\nInstead of using an arbitrary order, one can pre-order the jobs in order to attain better guarantees. Some known list scheduling strategies are:\nAnomalies.\nThe list scheduling algorithm has several anomalies. Suppose there are \"m\"=3 machines, and the job lengths are: 3, 2, 2, 2, 4, 4, 4, 4, 9Further, suppose that all the \"4\" jobs must be executed after the fourth \"2\" job. Then, list scheduling returns the following schedule:\nand the makespan is 12. \nAnomaly 1. If the \"4\" jobs do \"not\" depend on previous jobs anymore, then the list schedule is:\nand the makespan is 16. Removing dependencies has enlarged the makespan.\nAnomaly 2. Suppose the job lengths decrease by 1, to 2, 1, 1, 1, 3, 3, 3, 3, 8 (with the original dependencies). Then, the list schedule is:\nand the makespan is 13. Shortening all jobs has enlarged the makespan.\nAnomaly 3. Suppose there is one more machine (with the original lengths, with or without dependencies). Then, the list schedule is:\nand the makespan is 15. Adding a machine has enlarged the makespan.\nThe anomalies are bounded as follows. Suppose initially we had \"m\"1 machines and the makespan was \"t\"1. Now, we have \"m\"2 machines, the dependencies are the same or relaxed, the job lengths are the same or shorter, the list is the same or different, and the makespan is \"t\"2. Then:formula_4.In particular, with the same number of machines, the ratio is formula_5. A special case is when the original schedule is optimal; this yields the bound formula_5 on the approximation ratio.", "Engineering,_Manufacturing": 0.9993829131, "qwen": "Yes"}
{"id": "9269051", "revid": "1167103709", "url": "https://en.wikipedia.org/wiki?curid=9269051", "title": "Fulfillment house", "text": "Fulfillment house and fulfillment center (in British English: fulfilment house and fulfilment centre) are modern terms for a packing warehouse. The terms were coined in the middle of the 1990s, and \"fulfillment center\" is usually used about an in-house packing warehouse, while \"fulfillment house\" tends to be used about companies that specialize in warehousing and packing for others.\nOrigin of term.\nThe usage of the word \"'fulfillment\" in relation to goods shipments comes from the terms \"order fulfillment\" and \"product fulfillment\", which were introduced by business management researchers who analysed supply chains in the late 1980s. This was soon picked up by PR people working for picking warehouse companies, who felt that \"fulfillment centre\" or \"fulfillment house\" sounded more positive and active than the old term \"warehouse\". The terms are still so new and unknown by people outside that industry that \"warehouse\" often is added in parenthesis or used as an alternative word in the same text, in order to explain to laymen what \"fulfillment centre\" or \"fulfillment house\" actually means.\nExternal or internal.\nSome companies, such as Amazon, have their own fulfillment centers, while many smaller e-commerce companies outsource their warehousing, picking, packaging and shipping to external fulfillment companies. These external fulfillment companies are known as third-party logistic providers. Many larger companies with their own fulfillment centers also handle warehousing and shipping for other sellers. Amazon itself is one such example, offering to handle warehousing and order fulfillment to third-party sellers. Another, very early, example was Fingerhut, which in the 1990s expanded its own fulfillment center in order to take on fulfillment services for other companies, including the company that eventually acquired Fingerhut: Federated Department Stores.\nTypes.\nThere are multiple types of fulfillment houses. In the past, a fulfillment center was typically associated with filling larger commercial orders to a retailer or distributor. Today, with the growth of ecommerce, there are fulfillment centers that strictly focus on shipping small parcels direct-to-consumers (DTC). Additionally, some ecommerce fulfillment centers focus on a niche, such as small or large products, a specific type of product (for example - apparel), or they only with a certain number of stock keeping units (SKUs).\nA subset of ecommerce known as drop shipping, a type of product fulfillment that occurs directly from manufacturers to consumers via 3rd party retail websites, utilizes the manufacturer's or a wholesaler's fulfillment centers to deliver goods to the customer. In drop shipping, the company that generates the sale never handles the physical product, but it does pass on fulfillment requirements to the fulfillment house so that customer demands like two-day shipping can be met.\nFulfillment House Due Diligence Scheme.\nThe UK government believes that fulfillment houses are in a position to facilitate non-payment of VAT on goods imported into the UK. The government argues that this type of abuse is \"enabled by misdeclaration and undervaluation of goods imported from outside the EU, and sometimes the abuse of reliefs that are designed to facilitate trade. This is followed by the onward sale of the goods to customers in the UK taking place without the correct amounts of UK VAT being paid\" and believes that registering fulfillment houses and requiring due diligence and record-keeping is \"part of the solution\".\nProvision for this \"Fulfillment House Due Diligence Scheme\" is included in sections 48 to 59 of the Finance Bill 2017, introduced into the UK Parliament in September 2017.", "Engineering,_Manufacturing": 0.9980766177, "qwen": "Yes"}
{"id": "21067297", "revid": "237572", "url": "https://en.wikipedia.org/wiki?curid=21067297", "title": "Impact extrusion", "text": "Impact extrusion is a manufacturing process similar to extrusion and drawing by which products are made with a metal slug. The slug is pressed at a high velocity with extreme force into a die or mold by a punch.\nProcess.\nThe punch is attached to a mechanical or hydraulic press. These machines reciprocate in a cycle 20 to 60 times per minute. A cold slug is placed below the punch and over the die. The punch makes contact with the slug forcing it around the circumference of the punch and into the die. The metal slug deforms to fit the punch on the inside and the die on the outside. Lubricants are added to aid the machine for an easier punch-out. It only takes one impact for the finished shape to form from the slug. Once the slug has been contoured to the desired shape, a counter-punch ejector removes the work piece from within the die.\nSome Characteristics of the Process.\nThe wall thickness of the work piece is directly correlated with the clearance between the punch and die.\nThe thinner the wall of the work piece the tighter its tolerances are.\nThe end product has a better surface finish than the starting piece and the grain of the material is reformed to its new shape. This adds strength to the new form compared to cutting into the grain like in a machining process.\nEffects on Work Material Properties.\nAfter going through this process the properties of the material used are altered. Its hardness and yield strength are increased, cross-sectional area is decreased, some residual surface stresses will be present and micro cracks may appear. Physical and chemical properties are only influenced slightly.\nDie Style.\nFour major types of dies (tools) can be used. They are: forward, backward/reverse, combined, and hydrostatic extrusion. Forward extrusion pushes the slug into the die. Backward/reverse extrusion pushes the slug around the punch. Combined extrusion forces the slug both into the die and around the punch. Hydrostatic extrusion is used on brittle materials (i.e. molybdenum, beryllium, and tungsten) by applying pressure gradually to force the brittle material through the die. This is generally accomplished by the same method as forward extrusion.\nTypical Workpiece Materials.\nTypical materials for this process are: aluminium, brass, tin, mild steel, stainless steel, magnesium, titanium, and zinc.\nTool Materials.\nTypical tool steels used in extruding aluminum:\nTool Geometry.\nWhen using the technique of backward impact extrusion, putting an angle on the punch in the press is used to decrease the amount of pressure applied to the punch. This decreases the chance of creating a dead zone, which is an area of no pressure. On the opposite end of things, forward impact extrusion uses a radius on punch to keep the course in the workpiece material moving.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "21075865", "revid": "76", "url": "https://en.wikipedia.org/wiki?curid=21075865", "title": "Planing (shaping)", "text": "Planing is a manufacturing process of material removal in which the workpiece reciprocates against a stationary cutting tool producing a plane or sculpted surface. Planing is analogous to shaping. The main difference between these two processes is that in shaping the tool reciprocates across the stationary workpiece. Planing motion is the opposite of shaping. Both planing and shaping are rapidly being replaced by milling.\nThe mechanism used for this process is known as a planer. The size of the planer is determined by the largest workpiece that can be machined on it. The cutting tools are usually carbide tipped or made of high speed steel and resemble those used in facing and turning.\nProcess.\nIn shaping, the tool is brought into position with the workpiece. The tool then repeatedly moves in a straight line while the workpiece is incrementally fed into the line of motion of the tool, this produces a flat, smooth, and sculpted surface. For shaped pieces the tool reciprocates across the stationary workpiece. The tools are usually tilted or lifted after each stroke. This is done hydraulically or manually in order to prevent the tool surface from chipping when the workpiece travels back across.\nWorkpiece geometry.\nPlaning can be used to produce flat surfaces, as well as cross-sections with grooves and notches, are produced along the length of workpiece. Shaping is basically the same as planing, except the workpiece is usually smaller, and it is the tool that moves and not the workpiece.\nPlaning can be used to produce horizontal, vertical, or inclined flat surfaces on workpieces usually too large for shaping. Shaping is used not only for flat surfaces, but also for external or internal surfaces (either horizontal or inclined). Curved and irregular surfaces can also be produced by using special attachments\nSetup and equipment.\nFlat, angular, and contoured surfaces are made by horizontal shapers. Concerning shaping, the device that holds the piece being worked on has a very heavy movable jaw to withstand cutting forces. The size of the planer needed is determined by the workpiece. Depending on the size of the workpiece many clamps and supporting devices may be used to hold it on the planer.\nTypical tools and geometry produced.\nThe tools for shaping/planing are usually made of high speed steel or carbide tipped. Except for some slight angle difference, cutting tools resemble those used in facing and turning. Some advantages of using single-point cutting tools over multipoint tools is that they are more easily sharpened and fabricated. Internal shapes can be made by using a special extension tool. \nMaterial properties.\nAlthough the most common material to be planed or shaped is wood, there are planers and shaping machines capable of processing anything from metal pieces to plastic objects.\nReferences.\n[1] Todd, Robert H and Allen, Dell K. (1994) \"Manufacturing Processes Reference Guide\". New York, NY: Industrial Press Inc. pg. 124-125.", "Engineering,_Manufacturing": 0.9999598265, "qwen": "Yes"}
{"id": "21088038", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=21088038", "title": "Gear shaping", "text": "Gear shaping is a machining process for creating teeth on a gear using a cutter. Gear shaping is a convenient and versatile method of gear cutting. It involves continuous, same-plane rotational cutting of gear.\nProcess theory.\nThe types of cutters used for gear shaping can be grouped into four categories: disk, hub, shank, and helical cutters. The cutters are essentially gears that are used to form the teeth. This method of gear cutting is based on the principle that any two gears will mesh if they are of the same pitch, proper helix angle, and proper tooth depth and thickness.\nProcess characteristics.\nBy using a gear-shaped corresponding cutter that is rotated (in relation to a blank gear) produces the gear teeth. The cutters that are rotated are timed with the workpiece. This process produces internal gears, external gears, and integral gear-pinion arrangements.\nProcess schematic.\nThe process of gear shaping uses a toothed disk cutter which reciprocates in axial rotations. The workpiece (or blank gear) rotates on a second shaft (spindle). The workpiece is aligned with the cutter and it gradually feeds into the cutter while rotating. If a two-step process is used, all tooth spaces are partially cut before finishing.\nSetup and equipment.\nThe machine used for gear shaping generally consists of a base, column spindle, and an arbor. The gear cutter is mounted on the spindle, and the gear blank is mounted on the arbor. The cutter reciprocates up and down while the workpiece is gradually fed into the cutter. At the end of each cutting rotation, the spindle is retracted slightly to discourage any more cutting into the new cut teeth of the gear.", "Engineering,_Manufacturing": 1.0000044107, "qwen": "Yes"}
{"id": "21088679", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=21088679", "title": "Namiki Precision Jewel Co", "text": " is a Japanese component manufacturing company based in Tokyo, Japan. The company was founded in 1939 as a manufacturer of synthetic sapphire jewel bearings for electrical measuring instruments. Namiki supplies industrial jewel parts, dc coreless and dc brushless motors, multi-functional vibration components, precision gearheads, medical equipment, watch exterior parts, Analog Record-related Products and other precision components.\nNamiki merged with its affiliated company, Adamant Co., Ltd. on January 1, 2018, and changed its name to Adamant Namiki Precision Jewel Co., Ltd.. Adamant Namiki Precision Jewel Co., Ltd., and Akita Adamant Co., Ltd., merged in 2023 and the company was rebranded as Orbray Co., Ltd., on January 1, 2023.\nProducts.\nJewel Parts.\nNamiki supplies industrial jewel parts such as jewel bearings, phonograph diamond styli and cantilevers, watch exterior parts, and sapphire wafers which are made of synthetic sapphire which is produced in-house. They have developed sapphire step wafers, with a step height of 0.22 nanometres, which are expected to become the height standard for scanning probe microscopy (SPM), plus Immobilization plates for observing bio-materials.\nDC Motors.\nNamiki supplies DC coreless motors, DC brushless motors and geared motors. In 2004, they developed the world's smallest micro geared motor (diameter 1.5mm) for use in medical equipment, (catheters, endoscopes) and Micro-robots.\nDiaphragm Pumps.\nNamiki supplies diaphragm liquid and air pumps used in inkjet printers and biotechnology devices including incubation systems.\nVibration Components.\nNamiki vibration motors and multi-functional vibration speakers combining speaker, receiver, and vibration functions, are used in mobile phones.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "1930686", "revid": "22619", "url": "https://en.wikipedia.org/wiki?curid=1930686", "title": "Harvey Hubbell", "text": "Harvey Hubbell II (December 20, 1857 – December 17, 1927), was an American inventor, entrepreneur, and industrialist. His best-known inventions are the U.S. electrical plug and the pull-chain light socket.\nIn 1888, at the age of thirty-one, Hubbell quit his job as a manager of a manufacturing company and founded Hubbell Incorporated in Bridgeport, Connecticut, a company which is still in business today, still headquartered near Bridgeport. Hubbell began manufacturing consumer products and, by necessity, inventing manufacturing equipment for his factory. Some of the equipment he designed included automatic tapping machines and progressive dies for blanking and stamping. One of his most important industrial inventions, still in use today, is the thread rolling machine. He quickly began selling his newly devised manufacturing equipment alongside his commercial products.\nHubbell received at least 45 patents, most of which were for electric products. The pull-chain electrical light socket was patented in 1896, and his most famous invention, the U.S. electrical power plug, in 1904. It allowed the adoption in the U.S. of convenient, portable electrical devices, which Great Britain had enjoyed since the early 1880s. In 1916, Hubbell was also granted a patent for a three-bladed power plug, including an earth pin, which Australian regulators and electrical accessory manufacturers adopted as the standard for that country in the 1930s. It was also adopted in New Zealand, Argentina, and (with a minor variation) in China.", "Engineering,_Manufacturing": 0.9969987273, "qwen": "Yes"}
{"id": "406959", "revid": "6046731", "url": "https://en.wikipedia.org/wiki?curid=406959", "title": "Coil spring", "text": "The most common type of spring is the coil spring, which is made out of a long piece of metal that is wound around itself. \nCoil springs were in use in Roman times, evidence of this can be found in bronze Fibulae — the clasps worn by Roman soldiers among others. These are quite commonly found in Roman archeological digs.\nCoil springs can be either compression springs, tension springs or torsion springs, depending on how they are wound.\nA coil spring is a mechanical device which is typically used to store energy and subsequently release it, to absorb shock, or to maintain a force between contacting surfaces. They are made of an elastic material formed into the shape of a helix which returns to its natural length when unloaded.\nThey are commonly used in mattresses, automotive suspensions, and residential plumbing. Coil springs come in a variety of sizes and shapes and can be used for a variety of applications. Small coil springs are often used in electronic devices, while larger ones are used in automobile suspensions. Coil springs can be made from various materials, including steel, brass, and bronze.\nSpring rate.\nSpring rate is the measurement of how much a coil spring can hold until it compresses . The manufacture normally specifies the spring rate. If a spring has a rate of 100 then the spring would compress 1 inch (2.54 cm)  with of load.\nTypes.\nTypes of coil spring are:\nHeavy-duty springs.\nHeavy-duty springs are designed to withstand high levels of force and tension. They are typically used in industrial and commercial applications where heavy loads need to be supported or generated. Heavy-duty springs can be made from various materials, including steel, stainless steel, and titanium. They are typically much stiffer and thicker than standard springs (3 mm — 65 mm thick) and can have a wide range of sizes and shapes. Because of their strength and durability, heavy-duty springs are typically used in automotive and mining applications. They are also commonly used in construction, motorsport, rail and other industries where heavy equipment is used.\nDesign.\nSpring design must take into account the desired stiffness of the spring, as well as the amount of space that is available for the spring. In addition, springs must be designed to withstand the forces that will be applied to them, such as the car's weight or the gas pressure. Spring design is an important part of many engineering applications, and it is crucial to ensure that products work correctly and safely.\nApplications.\nCoil springs have many applications; notable ones include:\nCoil springs are commonly used in vehicle suspension. These springs are compression springs and can differ greatly in strength and in size depending on application. A coil spring suspension can be stiff to soft depending on the vehicle it is used on. Coil spring can be either mounted with a shock absorber or mounted separately. Coil springs in trucks allow them to ride smoothly when unloaded, and once loaded the spring compresses and becomes stiff. This allows the vehicle to bounce less when loaded. Coil spring suspension is also used in high performance cars so that the car can absorb bumps and have low body roll. In off-road vehicles, they are used because of their range of travel they allow at the wheel.\nCoil springs used in the engine are compression springs and play an important role in closing the valves that feed air and let exhaust gases out of the combustion chamber. The spring is attached to a rocker that is connected to the valve.\nTension and extension coil springs of a given material, wire diameter and coil diameter exert the same force when fully loaded; increased number of coils merely (linearly) increases free length and compressed/extended length.\nManufacture.\nMetal coil springs are made by winding a wire around a shaped former a cylinder is used to form cylindrical coil springs.\nSpring manufacture is the process of making springs by coiling, winding, or forming steel wire or other materials. Spring manufacturing includes various processes, including cold coiling and hot coiling. \nTo meet the demands of today's consumers, spring manufacturers must be able to produce springs in a wide range of sizes and shapes. As a result, spring manufacture has become increasingly complex and specialized. They must have a thorough understanding of spring design to produce quality products. In addition, they must be able to operate various machines to produce springs with the desired characteristics. Spring manufacture is a critical part of the economy, and spring makers play an important role in ensuring that products meet the highest quality standards.\nCoil springs for vehicles are typically made of hardened steel. A machine called an auto-coiler takes spring wire that has been heated, so it can easily be shaped. It is then fed onto a lathe that has a metal rod with the desired coil spring size. The machine takes the wire and guides it onto the spinning rod, as well as pushing it across the rod to form multiple coils. The spring is then ejected from the machine and an operator will put it in oil to cool off. The spring is then tempered to lose the brittleness from being cooled. The coil size and strength can be controlled by the lathe rod size and material used. Different alloys are used to get certain characteristics out of the spring, such as stiffness, dampening, and strength. ", "Engineering,_Manufacturing": 0.9999936819, "qwen": "Yes"}
{"id": "14004832", "revid": "222758", "url": "https://en.wikipedia.org/wiki?curid=14004832", "title": "Metal electrode leadless face", "text": "Metal electrode leadless face (MELF) is a type of leadless cylindrical electronic surface mount device that is metallized at its ends. MELF devices are usually diodes and resistors.\nThe EN 140401-803 and JEDEC DO-213 standards describe multiple MELF components.\nHandling difficulties.\nBecause of their cylindrical shape and small size, in some cases these components can easily roll off the workbench or circuit board before they have been soldered into place. As such, there is a joke which suggests an alternate meaning for the acronym: \"Most End up Lying on the Floor\". Additionally, MELF components are sometimes called a \"roll away\" package.\nDuring automated SMT pick-and-place, this happens mostly if the mechanical pressure of the SMD placer nozzle is too low. If the MELF components are placed into the solder paste with enough pressure, then this problem can be minimized. Care must be taken with glass diodes which are less mechanically robust than resistors and other MELF components.\nAlso, when building up PCBs via manual assembly using tweezers (e.g., for prototyping) then the pressure at the end of tweezers can often cause a MELF component to slip and shoot out the ends, thereby making their placement more difficult, compared to other flat component packages.\nAnother reason for the nickname of MELF components is that most production engineers do not like to use MELF nozzles on a SMT pick-and-place machine. For them it is waste of time to change from flat nozzles to MELF nozzles. For MICRO-MELF and MINI-MELF most SMD placers are able to use flat chip nozzles if the vacuum is high enough; i.e., higher than for flat chip components. For MELFs with the case size of 0207 or less, it is recommended to use the original MELF nozzle supplied with the SMT machine. Each supplier of such SMD pick-and-place machines offers these types of nozzles.\nIn order to overcome some of the difficulties encountered when mounting these devices, there are also variants with square electrodes (e.g. SQ MELF, QuadroMELF and B-MELF). These variants are mainly used in semiconductor diodes for applications where the high-reliability of hermetically sealed voidless-glass packages is required.\nThese handling difficulties prompted development of alternative SMT packages for common MELF components (like diodes) where the power handling capability needed to be similar to MELF components (superior to low-power 0805/0603, etc. SMT components) but with improved automated pick-and-place handling characteristics. This resulted in various squared-off packages with fold-over contacts, similar to rectangular inductor/tantalum capacitor packages.\nTechnical advantages.\nDespite their handling difficulties, and in the particular case of MELF resistors, they are still widely used in high-reliability and precision applications where their predictable characteristics (e.g., low failure rate with well-defined failure modes) as well as their higher performance in terms of accuracy, long-term stability, moisture resistance, high-temperature operation far outweigh their disadvantages.", "Engineering,_Manufacturing": 0.9999746084, "qwen": "Yes"}
{"id": "11612027", "revid": "8372814", "url": "https://en.wikipedia.org/wiki?curid=11612027", "title": "Spreader (lifting)", "text": "A spreader is a device used for lifting containers and unitized cargo. The spreader is placed between the container and the lifting machine.\nThe spreader used for containers has a locking mechanism at each corner that attaches to the four corners of the container. A spreader can be used on a container crane, a straddle carrier and with any other machinery to lift containers. Spreader operation can be manual, semiautomatic or fully automatic.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "11633530", "revid": "46208898", "url": "https://en.wikipedia.org/wiki?curid=11633530", "title": "Injection molding machine", "text": "An injection molding machine (also spelled as injection moulding machine in BrE), also known as an injection press, is a machine for manufacturing plastic products by the injection molding process. It consists of two main parts, an \"injection unit\" and a \"clamping unit\".\nOperation.\nInjection molding machine molds can be fastened in either a horizontal or vertical position. Most machines are horizontally oriented, but vertical machines are used in some niche applications such as insert molding, allowing the machine to take advantage of gravity. Some vertical machines also do not require the mold to be fastened. There are many ways to fasten the tools to the platens, the most common are manual clamps (both halves are bolted to the platens); however, hydraulic clamps (chocks are used to hold the tool in place) and magnetic clamps are also used. The magnetic and hydraulic clamps are used where fast tool changes are required.\nThe person designing the mold chooses whether the mold uses a cold runner system or a hot runner system to carry the plastic and fillers from the injection unit to the cavities.\nA cold runner is a simple channel carved into the mold.\nThe plastic that fills the cold runner cools as the part cools and is then ejected with the part as a sprue.\nA hot runner system is more complicated, often using cartridge heaters to keep the plastic in the runners hot as the part cools.\nAfter the part is ejected, the plastic remaining in a hot runner is injected into the next part.\nTypes of injection molding machines.\nMachines are classified primarily by the type of driving systems they use: hydraulic, mechanical, electrical, or hybrid\nHydraulic.\nHydraulic machines have historically been the only option available to molders until Nissei Plastic Industrial introduced the first all-electric injection molding machine in 1983. Hydraulic machines, although not nearly as precise, are the predominant type in most of the world, with the exception of Japan.\nMechanical.\nMechanical type machines use the toggle system for building up tonnage on the clamps of the machine. Tonnage is required on all machines so that the clamps of the machine do not open due to the injection pressure. If the mold partially opens up, it will create flashing in the plastic product.\nElectric.\nThe electric press, also known as Electric Machine Technology (EMT), reduces operation costs by cutting energy consumption and also addresses some of the environmental concerns surrounding the hydraulic press. Electric presses have been shown to be quieter, faster, and have a higher accuracy, however the machines are more expensive.\nHybrid injection (sometimes referred to as \"Servo-Hydraulic\") molding machines claim to take advantage of the best features of both hydraulic and electric systems, but in actuality use almost the same amount of electricity to operate as an electric injection molding machine depending on the manufacturer.\nA robotic arm is often used to remove the molded components; either by side or top entry, but it is more common for parts to drop out of the mold, through a chute and into a container.\nMain components of injection molding machine.\nInjection unit.\nConsists of three main components:\nClamping unit.\nConsists of three main components:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "2793268", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=2793268", "title": "Control arm", "text": "In automotive suspension, a control arm, also known as an A-arm, is a hinged suspension link between the chassis and the suspension upright or hub that carries the wheel. In simple terms, it governs a wheel's vertical travel, allowing it to move up or down when driving over bumps, into potholes, or otherwise reacting to the irregularities of a road surface. Most control arms form the lower link of a suspension. Control arms play a crucial role in the suspension system of a vehicle. They help to keep the wheels aligned and maintain proper tire contact with the road, which is essential for safety and stability. \nThe inboard (chassis) end of a control arm is attached by a single pivot, usually a rubber bushing. It can thus control the position of the outboard end in only a single degree of freedom, maintaining the radial distance from the inboard mount. Although not deliberately free to move, the single bushing does not control the arm from moving back and forth; this motion is constrained by a separate link or radius rod.\nThis is in contrast to the wishbone, which are triangular and have two widely spaced inboard bearings. These constrain the outboard end of the wishbone from moving back and forth, controlling two degrees of freedom, and without requiring additional links. Certain vehicles -- notably, many Honda products from the 1990s -- feature what's known as a double wishbone suspension. A double wishbone design features both upper and lower control arms that work in tandem with each other to properly locate the wheel. The additional radius rod is then attached to the upper arm.\nMacPherson strut.\nControl arms are most commonly encountered as part of the MacPherson strut independent front suspension. The control arms are perpendicular to the axis of the vehicle and are termed \"track control arms\". A diagonal \"radius rod\" constrains the strut from moving forward and back.\nIn MacPherson's original design, an anti-roll bar also acted as the radius rod. This requires the bar to be attached through a ball joint, so as to also provide longitudinal control. In most contemporary designs, still commonly termed MacPherson struts, the radius rod and anti-roll bar are now separate, with the anti-roll bar mounted in a sliding bush.\nSpring attachment.\nA control arm may be used to carry the suspension load and transmit them to the spring or shock absorber. Torsion bar suspension commonly does this, with the outboard end of the torsion bar attached to the inboard bearing of the control arm..", "Engineering,_Manufacturing": 0.9999519587, "qwen": "Yes"}
{"id": "2793738", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=2793738", "title": "Metal injection molding", "text": "Metal injection molding (MIM) is a metalworking process in which finely-powdered metal is mixed with binder material to create a \"feedstock\" that is then shaped and solidified using injection molding. The molding process allows high volume, complex parts to be shaped in a single step. After molding, the part undergoes conditioning operations to remove the binder (debinding) and densify the powders. Finished products are small components used in many industries and applications.\nThe behavior of MIM feedstock is governed by rheology, the study of sludges, suspensions, and other non-Newtonian fluids.\nDue to current equipment limitations, products must be molded using quantities of 100 grams or less per \"shot\" into the mold. This shot can be distributed into multiple cavities, making MIM cost-effective for small, intricate, high-volume products, which would otherwise be expensive to produce. MIM feedstock can be composed of a plethora of metals, but most common are stainless steels, widely used in powder metallurgy. After the initial molding, the feedstock binder is removed, and the metal particles are diffusion bonded and densified to achieve the desired strength properties. The latter operation typically shrinks the product by 15% in each dimension.\nAdopted by a variety of industries MIM manufacturing is well-suited to produce medium to high volume components by increasing the number of mold cavities. Ideal candidates include those that weigh less than 100 grams, have complex geometries and tight tolerances, and can fit in the palm of your hand.\nThe metal injection molding market has grown from US$9 million in 1986, to US$382 million in 2004 to more than US$1.5 billion in 2015. A related technology is ceramic powder injection molding, leading to about US$2 billion total sales. Most of the growth in recent years has been in Asia.\nProcess.\nIn the monograph P.O. Gribovsky, published in 1956, describes in detail the technology of hot casting (hot molding) ceramic products under pressure (now, Low Pressure Powder Injection Molding) and, in particular, notes that \"hot casting technology provides the ability to manufacture products from any solid materials, ranging from natural minerals, pure oxides, carbides, metals, etc., and ending with multicomponent composite synthetic materials and their combinations\". This indication of the possibility of MIM-casting, which was implemented by Dr. Raymond E. Wiech Jr. in the 1970s, who refined MIM technology as co-founder of a California company named Parmatech, the name being condensed from the phrase \"particle materials technology\". Wiech later patented his process, and it was widely adopted for manufacturing use in the 1980s.\nMIM gained recognition throughout the 1990s as improvements to subsequent conditioning processes resulted in an end product that performs similarly to or better than those made through competing processes. MIM technology improved cost efficiency through high volume production to \"net-shape\", negating costly, additional operations such as machining although MIM is weak in terms of tight dimensional specifications.\nThe process steps involve combining metal powders with polymers such as wax and polypropylene binders to produce the \"feedstock\" mix that is injected as a liquid into a mold using plastic injection molding machines. The molded or \"green part\" is cooled and ejected from the mold. Next, a portion of the binder material is removed using solvent, thermal furnaces, catalytic process, or a combination of methods. The resulting, fragile and porous (40 volume percent \"air\") part, is in a condition called the \"brown\" stage. To improve handling often the debinding and sintering are combined into a single process. Sintering heats the powder to temperatures near the melting point in a protective atmosphere furnace to densify the particles using capillary forces in a process called sintering. MIM parts are often sintered at temperatures nearly high enough to induce partial melting in a process termed liquid phase sintering. For example, a stainless steel might be heated to . Diffusion rates are high leading to high shrinkage and densification. If performed in vacuum, it is common to reach 96–99% solid density. The end-product metal has comparable mechanical and physical properties with annealed parts made using classic metalworking methods. Post sintering heat treatments for MIM are the same as with other fabrication routes, and with high density the MIM component is compatible with the metal conditioning treatments such as plating, passivating, annealing, carburizing, nitriding, and precipitation hardening.\nApplications.\nThe window of economic advantage in metal injection molded parts lies in complexity and volume for small-size parts. MIM materials are comparable to metal formed by competing methods, and final products are used in a broad range of industrial, commercial, medical, dental, firearms, aerospace, and automotive applications. Dimensional tolerances of ±0.3% are common and machining is required for closer tolerances. MIM can produce parts where it is difficult, or even impossible, to efficiently manufacture an item through other means of fabrication. Ideally, at least 75 dimensional specifications in a component of just 25 mm maximum size and 10 g mass is best – as for example required for watch cases, cellular telephone plugs, and laptop computer hinges. Increased costs for traditional manufacturing methods inherent to part complexity, such as internal/external threads, miniaturization, or identity marking, typically do not increase the cost in a MIM operation due to the flexibility of injection molding.\nOther design capabilities that can be implemented into the MIM operation include product codes, part numbers, or date stamps; parts manufactured to their net weight reducing material waste and cost; Density controlled to within 95–98%; Amalgamation of parts and Complex 3D Geometries.\nThe ability to combine several operations into one process ensures MIM is successful in saving lead times as well as costs, providing significant benefits to manufacturers. The metal injection molding process might be a green technology due to the significant reduction in wastage compared to \"traditional\" manufacturing methods such as 5 axis CNC machining. However, some of the older operations generate toxic emissions such as formaldehyde, dispose of chlorinated solvents, and must burn off wax or other polymers, leading to greenhouse gas emissions.\nThere is a broad range of materials available when utilizing the MIM process. Traditional metalworking processes often involve a significant amount of material waste, which makes MIM a highly efficient option for the fabrication of complex components consisting of expensive/special alloys (cobalt-chrome, 17-4 PH stainless steel, titanium alloys and tungsten carbides). MIM is a viable option when extremely thin walls specifications (i.e., 100 micrometers) are required. Additionally, electromagnetic interference shielding requirements have presented unique challenges, which are being successfully attained through the utilization of specialty alloys (ASTM A753 Type 4).\nDisadvantages.\nAlthough MIM has many advantages, it also has disadvantages:\nSee also.\nDie casting", "Engineering,_Manufacturing": 1.0000002384, "qwen": "Yes"}
{"id": "2794785", "revid": "14965160", "url": "https://en.wikipedia.org/wiki?curid=2794785", "title": "Hubs and nodes", "text": "Hubs and nodes is a geographic model explaining how linked regions can co-operate to fulfill elements of an industry's value chain and collectively gain sufficient mass to drive innovation growth. The model of hubs and nodes builds on Porter's cluster model which served well in the past, but as businesses and regions around the world have adjusted to the realities of globalization, the concept of clusters is becoming outdated.\nDisaggregation of clusters.\nCompanies are realizing that they may not require a particular stage of production to be in close geographic proximity. As barriers to long-distance national and global transactions have fallen through advances in technology and logistics, such as the growth of the Internet and overnight package services, it has become increasingly possible to relocate operations such as research, product development, and manufacturing to countries and regions with relevant expertise and lower costs. It is common among consumer goods, for example, to have concept generation centered in one locale, product testing and refinement in another, and manufacturing and distribution in still others. Elements of development, production and distribution are being more and more completed beyond the borders of historical clusters. \nAs more companies progress beyond the cluster model, they increasingly expand and diversify their operations to locations where their investments will be most profitable. For companies adequately prepared for the rapid globalization process, their research and development, manufacturing and distribution stages fare better as these businesses are able to reduce their costs and potentially realizing new efficiencies and increased speeds of product development. The spirit of the cluster model may remain intact, and the various stages of production will still be shared by a number of different entities, but geographical proximity need no longer bind the entities together", "Engineering,_Manufacturing": 0.9917061925, "qwen": "Yes"}
{"id": "329549", "revid": "6727347", "url": "https://en.wikipedia.org/wiki?curid=329549", "title": "Surface of revolution", "text": "A surface of revolution is a surface in Euclidean space created by rotating a curve (the \"generatrix\") one full revolution around an \"axis of rotation\" (normally not intersecting the generatrix, except at its endpoints).\nThe volume bounded by the surface created by this revolution is the \"solid of revolution\".\nExamples of surfaces of revolution generated by a straight line are cylindrical and conical surfaces depending on whether or not the line is parallel to the axis. A circle that is rotated around any diameter generates a sphere of which it is then a great circle, and if the circle is rotated around an axis that does not intersect the interior of a circle, then it generates a torus which does not intersect itself (a ring torus).\nProperties.\nThe sections of the surface of revolution made by planes through the axis are called \"meridional sections\". Any meridional section can be considered to be the generatrix in the plane determined by it and the axis.\nThe sections of the surface of revolution made by planes that are perpendicular to the axis are circles.\nSome special cases of hyperboloids (of either one or two sheets) and elliptic paraboloids are surfaces of revolution. These may be identified as those quadratic surfaces all of whose cross sections perpendicular to the axis are circular.\nArea formula.\nIf the curve is described by the parametric functions , with ranging over some interval , and the axis of revolution is the -axis, then the area is given by the integral\nprovided that is never negative between the endpoints and . This formula is the calculus equivalent of Pappus's centroid theorem. The quantity\ncomes from the Pythagorean theorem and represents a small segment of the arc of the curve, as in the arc length formula. The quantity is the path of (the centroid of) this small segment, as required by Pappus' theorem.\nLikewise, when the axis of rotation is the -axis and provided that is never negative, the area is given by\nIf the continuous curve is described by the function , then the integral becomes\nfor revolution around the -axis, and\nfor revolution around the \"y\"-axis (provided ). These come from the above formula.\nFor example, the spherical surface with unit radius is generated by the curve , when ranges over . Its area is therefore\nFor the case of the spherical curve with radius , rotated about the -axis\nA minimal surface of revolution is the surface of revolution of the curve between two given points which minimizes surface area. A basic problem in the calculus of variations is finding the curve between two points that produces this minimal surface of revolution.\nThere are only two minimal surfaces of revolution (surfaces of revolution which are also minimal surfaces): the plane and the catenoid.\nCoordinate expressions.\nA surface of revolution given by rotating a curve described by formula_8 around the x-axis may be most simply described by formula_9. This yields the parametrization in terms of formula_10 and formula_11 as formula_12. If instead we revolve the curve around the y-axis, then the curve is described by formula_13, yielding the expression formula_14 in terms of the parameters formula_10 and formula_11. \nIf x and y are defined in terms of a parameter formula_17, then we obtain a parametrization in terms of formula_17 and formula_11. If formula_10 and formula_21 are functions of formula_17, then the surface of revolution obtained by revolving the curve around the x-axis is described by formula_23, and the surface of revolution obtained by revolving the curve around the y-axis is described by formula_24.\nGeodesics.\nMeridians are always geodesics on a surface of revolution. Other geodesics are governed by Clairaut's relation.\nToroids.\nA surface of revolution with a hole in, where the axis of revolution does not intersect the surface, is called a toroid. For example, when a rectangle is rotated around an axis parallel to one of its edges, then a hollow square-section ring is produced. If the revolved figure is a circle, then the object is called a torus.\nApplications.\nThe use of surfaces of revolution is essential in many fields in physics and engineering. When certain objects are designed digitally, revolutions like these can be used to determine surface area without the use of measuring the length and radius of the object being designed.", "Engineering,_Manufacturing": 0.9903190732, "qwen": "Yes"}
{"id": "331936", "revid": "307355", "url": "https://en.wikipedia.org/wiki?curid=331936", "title": "Brazing", "text": "Brazing is a metal-joining process in which two or more metal items are joined together by melting and flowing a filler metal into the joint, with the filler metal having a lower melting point than the adjoining metal.\nBrazing differs from welding in that it does not involve melting the work pieces. Brazing differs from soldering through the use of a higher temperature and much more closely fitted parts than when soldering. During the brazing process, the filler metal flows into the gap between close-fitting parts by capillary action. The filler metal is brought slightly above its melting (liquidus) temperature while protected by a suitable atmosphere, usually a flux. It then flows over the base metal (in a process known as wetting) and is then cooled to join the work pieces together. A major advantage of brazing is the ability to join the same or different metals with considerable strength.\nProcess.\nBrazing has many advantages over other metal-joining techniques, such as welding. Since brazing does not melt the base metal of the joint, it allows much tighter control over tolerances and produces a clean joint without the need for secondary finishing. Additionally, dissimilar metals and non-metals (i.e. metalized ceramics) can be brazed. In general, brazing also produces less thermal distortion than welding due to the uniform heating of a brazed piece. Complex and multi-part assemblies can be brazed cost-effectively. Welded joints must sometimes be ground flush, a costly secondary operation that brazing does not require because it produces a clean joint. Another advantage is that the brazing can be coated or clad for protective purposes. Finally, brazing is easily adapted to mass production and it is easy to automate because the individual process parameters are less sensitive to variation.\nOne of the main disadvantages is the lack of joint strength as compared to a welded joint due to the softer filler metals used. The strength of the brazed joint is likely to be less than that of the base but greater than the filler metal. Another disadvantage is that brazed joints can be damaged under high service temperatures. Brazed joints require a high degree of base-metal cleanliness when done in an industrial setting. Some brazing applications require the use of adequate fluxing agents to control cleanliness. The joint color is often different from that of the base metal, creating an aesthetic disadvantage.\nHigh-quality brazed joints require that parts be closely fitted with base metal surfaces exceptionally clean and free of oxides. In most cases, joint clearances of are recommended for the best capillary action and joint strength; in some brazing operations, however, it is not uncommon to have joint clearances around . Cleanliness of the brazing surfaces is also important, as any contamination can cause poor wetting (flow). The two main methods for cleaning parts, prior to brazing, are chemical cleaning and abrasive or mechanical cleaning. In the case of mechanical cleaning it is important to maintain the proper surface roughness, as wetting on a rough surface occurs much more readily than on a smooth surface of the same geometry.\nAnother consideration is the effect of temperature and time on the quality of brazed joints. As the temperature of the braze alloy is increased, the alloying and wetting action of the filler metal increases as well. In general, the brazing temperature selected must be above the melting point of the filler metal. However, several factors influence the joint designer's temperature selection. The best temperature is usually selected to:\nIn some cases, a worker may select a higher temperature to accommodate other factors in the design (e.g., to allow use of a different filler metal, or to control metallurgical effects, or to sufficiently remove surface contamination). The effect of time on the brazed joint primarily affects the extent to which these effects are present. In general, however, most production processes are selected to minimize brazing time and associated costs. This is not always the case, however, since in some non-production settings, time and cost are secondary to other joint attributes (e.g., strength, appearance).\nTechniques.\nThere are many heating methods available to accomplish brazing operations. The most important factor in choosing a heating method is achieving efficient transfer of heat throughout the joint and doing so within the heat capacity of the individual base metals used. The geometry of the braze joint is also a crucial factor to consider, as is the rate and volume of production required. The easiest way to categorize brazing methods is to group them by heating method. Here are some of the most common:\nThese heating methods are classified through localised and diffuse heating techniques and offer advantages based on their different applications.\nTorch brazing.\nTorch brazing is by far the most common method of mechanized brazing in use. It is best used in small production volumes or in specialized operations, and in some countries, it accounts for a majority of the brazing taking place. There are three main categories of torch brazing in use: manual, machine, and automatic torch brazing.\n\"Manual torch brazing\" is a procedure where the heat is applied using a gas flame placed on or near the joint being brazed. The torch can either be hand held or held in a fixed position depending on whether the operation is completely manual or has some level of automation. Manual brazing is most commonly used on small production volumes or in applications where the part size or configuration makes other brazing methods impossible. The main drawback is the high labor cost associated with the method as well as the operator skill required to obtain quality brazed joints. The use of flux or self-fluxing material is required to prevent oxidation. Torch brazing of copper can be done without the use of flux if it is brazed with a torch using oxygen and hydrogen gas, rather than oxygen and other flammable gases.\n\"Machine torch brazing\" is commonly used where a repetitive braze operation is being carried out. This method is a mix of both automated and manual operations with an operator often placing brazes material, flux and jigging parts while the machine mechanism carries out the actual braze. The advantage of this method is that it reduces the high labor and skill requirement of manual brazing. The use of flux is also required for this method as there is no protective atmosphere, and it is best suited to small to medium production volumes.\n\"Automatic torch brazing\" is a method that almost eliminates the need for manual labor in the brazing operation, except for loading and unloading of the machine. The main advantages of this method are: a high production rate, uniform braze quality, and reduced operating cost. The equipment used is essentially the same as that used for Machine torch brazing, with the main difference being that the machinery replaces the operator in the part preparation.\nFurnace brazing.\nFurnace brazing is a semi-automatic process used widely in industrial brazing operations due to its adaptability to mass production and use of unskilled labor. There are many advantages of furnace brazing over other heating methods that make it ideal for mass production. One main advantage is the ease with which it can produce large numbers of small parts that are easily jigged or self-locating. The process also offers the benefits of a controlled heat cycle (allowing use of parts that might distort under localized heating) and no need for post braze cleaning. Common atmospheres used include: inert, reducing or vacuum atmospheres all of which protect the part from oxidation. Some other advantages include: low unit cost when used in mass production, close temperature control, and the ability to braze multiple joints at once. Furnaces are typically heated using either electric, gas or oil depending on the type of furnace and application. However, some of the disadvantages of this method include: high capital equipment cost, more difficult design considerations and high power consumption.\nThere are four main types of furnaces used in brazing operations: batch type; continuous; retort with controlled atmosphere; and vacuum.\nA \"batch\" type furnace has relatively low initial equipment costs, and can heat each part load separately. It can turned on and off at will, which reduces operating expenses when it's not in use. These furnaces are suited to medium to large volume production, and offer a large degree of flexibility in type of parts that can be brazed. Either controlled atmospheres or flux can be used to control oxidation and cleanliness of parts.\n\"Continuous type\" furnaces are best suited to a steady flow of similar-sized parts through the furnace. These furnaces are often conveyor fed, moving parts through the hot zone at a controlled speed. It is common to use either controlled atmosphere or pre-applied flux in continuous furnaces. In particular, these furnaces offer the benefit of very low manual labor requirements and so are best suited to large scale production operations.\n\"Retort-type\" furnaces differ from other batch-type furnaces in that they make use of a sealed lining called a \"retort\". The retort is generally sealed with either a gasket or is welded shut and filled completely with the desired atmosphere and then heated externally by conventional heating elements. Due to the high temperatures involved, the retort is usually made of heat resistant alloys that resist oxidation. Retort furnaces are often either used in a batch or semi-continuous versions.\n\"Vacuum furnaces\" is a relatively economical method of oxide prevention and is most often used to braze materials with very stable oxides (aluminum, titanium and zirconium) that cannot be brazed in atmosphere furnaces. Vacuum brazing is also used heavily with refractory materials and other exotic alloy combinations unsuited to atmosphere furnaces. Due to the absence of flux or a reducing atmosphere, the part cleanliness is critical when brazing in a vacuum. The three main types of vacuum furnace are: single-wall hot retort, double-walled hot retort, and cold-wall retort. Typical vacuum levels for brazing range from pressures of 1.3 to 0.13 pascals (10−2 to 10−3 Torr) to 0.00013 Pa (10−6 Torr) or lower. Vacuum furnaces are most commonly batch-type, and they are suited to medium and high production volumes.\nSilver brazing.\nSilver brazing, sometimes known as hard soldering, is brazing using a silver alloy based filler. These silver alloys consist of many different percentages of silver and other metals, such as copper, zinc and cadmium.\nBrazing is widely used in the tool industry to fasten \"hard metal\" (carbide, ceramics, cermet, and similar) tips to tools such as saw blades. \"Pretinning\" is often done: the braze alloy is melted onto the hard metal tip, which is placed next to the steel and remelted. Pretinning gets around the problem that hard metals are difficult to wet.\nBrazed hard metal joints are typically two to seven mils thick. The braze alloy joins the materials and compensates for the difference in their expansion rates. It also provides a cushion between the hard carbide tip and the hard steel, which softens impact and prevents tip loss and damage—much as a vehicle's suspension helps prevent damage to the tires and the vehicle. Finally, the braze alloy joins the other two materials to create a composite structure, much as layers of wood and glue create plywood. The standard for braze joint strength in many industries is a joint that is stronger than either base material, so that when under stress, one or other of the base materials fails before the joint. Silver brazing may cause defects in certain alloys, e.g. stress-induced inter-granular cracking in copper-nickel.\nOne special silver brazing method is called ' or '. It has been developed especially for connecting cables to railway track or for cathodic protection installations. The method uses a silver- and flux-containing brazing pin, which is melted in the eye of a cable lug. The equipment is normally powered from batteries.\nBraze welding.\n\"Braze welding\" is the use of a bronze or brass filler rod coated with flux to join steel workpieces. The equipment needed for braze welding is basically identical to the equipment used in brazing. Since braze welding usually requires more heat than brazing, acetylene or methylacetylene-propadiene gas (MAPP gas) fuel is commonly used. The name comes from the fact that no capillary action is used.\nBraze welding has many advantages over fusion welding. It allows the joining of dissimilar metals, minimization of heat distortion, and can reduce the need for extensive pre-heating. Additionally, since the metals joined are not melted in the process, the components retain their original shape; edges and contours are not eroded or changed by the formation of a fillet. Another effect of braze welding is the elimination of stored-up stresses that are often present in fusion welding. This is extremely important in the repair of large castings. The disadvantages are the loss of strength when subjected to high temperatures and the inability to withstand high stresses.\nCarbide, cermet and ceramic tips are plated and then joined to steel to make tipped band saws. The plating acts as a braze alloy.\nCast iron \"welding\".\nThe \"welding\" of cast iron is usually a brazing operation, with a filler rod made chiefly of nickel being used although true welding with cast iron rods is also available.\nDuctile cast iron pipe may be also \"cadwelded,\" a process that connects joints by means of a small copper wire fused into the iron when previously ground down to the bare metal, parallel to the iron joints being formed as per hub pipe with neoprene gasket seals. The purpose behind this operation is to use electricity along the copper for keeping underground pipes warm in cold climates.\nVacuum brazing.\nVacuum brazing is a material joining technique that offers significant advantages: extremely clean, superior, flux-free braze joints of high integrity and strength. The process can be expensive because it must be performed inside a vacuum chamber vessel. Temperature uniformity is maintained on the work piece when heating in a vacuum, greatly reducing residual stresses due to slow heating and cooling cycles. This, in turn, can significantly improve the thermal and mechanical properties of the material, thus providing unique heat treatment capabilities. One such capability is heat-treating or age-hardening the workpiece while performing a metal-joining process, all in a single furnace thermal cycle.\nProducts that are most commonly vacuum-brazed include aluminum cold plates, plate-fin heat exchangers, and flat tube heat exchangers.\nVacuum brazing is often conducted in a furnace; this means that several joints can be made at once because the whole workpiece reaches the brazing temperature. The heat is transferred using radiation, as many other methods cannot be used in a vacuum.\nDip brazing.\nDip brazing is especially suited for brazing aluminium because air is excluded, thus preventing the formation of oxides. The parts to be joined are fixtured and the brazing compound applied to the mating surfaces, typically in slurry form. Then the assemblies are dipped into a bath of molten salt (typically NaCl, KCl and other compounds), which functions as both heat transfer medium and flux. Many dip brazed parts are used in heat transfer applications for the aerospace industry.\nFiller materials.\nA variety of alloys are used as filler metals for brazing depending on the intended use or application method. In general, braze alloys are composed of three or more metals to form an alloy with the desired properties. The filler metal for a particular application is chosen based on its ability to: wet the base metals, withstand the service conditions required, and melt at a lower temperature than the base metals or at a very specific temperature.\nBraze alloy is generally available as rod, ribbon, powder, paste, cream, wire and preforms (such as stamped washers). Depending on the application, the filler material can be pre-placed at the desired location or applied during the heating cycle. For manual brazing, wire and rod forms are generally used as they are the easiest to apply while heating. In the case of furnace brazing, the alloy is usually placed beforehand since the process is usually highly automated. Some of the more common types of filler metals used are\nSome brazes come in the form of \"trifoils\", laminated foils of a carrier metal clad with a layer of braze at each side. The center metal is often copper; its role is to act as a carrier for the alloy, to absorb mechanical stresses due to e.g. differential thermal expansion of dissimilar materials (e.g. a carbide tip and a steel holder), and to act as a diffusion barrier (e.g. to stop diffusion of aluminium from aluminium bronze to steel when brazing these two).\nBrazing alloys form several distinct groups; the alloys in the same group have similar properties and uses.\nSome additives and impurities act at very low levels. Both positive and negative effects can be observed. Strontium at levels of 0.01% refines grain structure of aluminium. Beryllium and bismuth at similar levels help disrupt the passivation layer of aluminium oxide and promote wetting. Carbon at 0.1% impairs corrosion resistance of nickel alloys. Aluminium can embrittle mild steel at 0.001%, phosphorus at 0.01%.\nIn some cases, especially for vacuum brazing, high-purity metals and alloys are used. 99.99% and 99.999% purity levels are available commercially.\nCare must be taken to not introduce deleterious impurities from joint contamination or by dissolution of the base metals during brazing.\nMelting behavior.\nAlloys with larger span of solidus/liquidus temperatures tend to melt through a \"mushy\" state, during which the alloy is a mixture of solid and liquid material. Some alloys show tendency to liquation, separation of the liquid from the solid portion; for these the heating through the melting range must be sufficiently fast to avoid this effect. Some alloys show extended plastic range, when only a small portion of the alloy is liquid and most of the material melts at the upper temperature range; these are suitable for bridging large gaps and for forming fillets. Highly fluid alloys are suitable for penetrating deep into narrow gaps and for brazing tight joints with narrow tolerances but are not suitable for filling larger gaps. Alloys with wider melting range are less sensitive to non-uniform clearances.\nWhen the brazing temperature is suitably high, brazing and heat treatment can be done in a single operation simultaneously.\nEutectic alloys melt at single temperature, without mushy region. Eutectic alloys have superior spreading; non-eutectics in the mushy region have high viscosity and at the same time attack the base metal, with correspondingly lower spreading force. Fine grain size gives eutectics both increased strength and increased ductility. Highly accurate melting temperature lets joining process be performed only slightly above the alloy's melting point. On solidifying, there is no mushy state where the alloy appears solid but is not yet; the chance of disturbing the joint by manipulation in such state is reduced (assuming the alloy did not significantly change its properties by dissolving the base metal). Eutectic behavior is especially beneficial for solders.\nMetals with fine grain structure before melting provide superior wetting to metals with large grains. Alloying additives (e.g. strontium to aluminium) can be added to refine grain structure, and the preforms or foils can be prepared by rapid quenching. Very rapid quenching may provide amorphous metal structure, which possess further advantages.\nInteraction with base metals.\nFor successful wetting, the base metal must be at least partially soluble in at least one component of the brazing alloy. The molten alloy therefore tends to attack the base metal and dissolve it, slightly changing its composition in the process. The composition change is reflected in the change of the alloy's melting point and the corresponding change of fluidity. For example, some alloys dissolve both silver and copper; dissolved silver lowers their melting point and increases fluidity, copper has the opposite effect.\nThe melting point change can be exploited. As the remelt temperature can be increased by enriching the alloy with dissolved base metal, step brazing using the same braze can be possible.\nAlloys that do not significantly attack the base metals are more suitable for brazing thin sections.\nNonhomogenous microstructure of the braze may cause non-uniform melting and localized erosions of the base metal.\nWetting of base metals can be improved by adding a suitable metal to the alloy. Tin facilitates wetting of iron, nickel, and many other alloys. Copper wets ferrous metals that silver does not attack, copper-silver alloys can therefore braze steels silver alone won't wet. Zinc improves wetting of ferrous metals, indium as well. Aluminium improves wetting of aluminium alloys. For wetting of ceramics, reactive metals capable of forming chemical compounds with the ceramic (e.g. titanium, vanadium, zirconium...) can be added to the braze.\nDissolution of base metals can cause detrimental changes in the brazing alloy. For example, aluminium dissolved from aluminium bronzes can embrittle the braze; addition of nickel to the braze can offset this.\nThe effect works both ways; there can be detrimental interactions between the braze alloy and the base metal. Presence of phosphorus in the braze alloy leads to formation of brittle phosphides of iron and nickel, phosphorus-containing alloys are therefore unsuitable for brazing nickel and ferrous alloys. Boron tends to diffuse into the base metals, especially along the grain boundaries, and may form brittle borides. Carbon can negatively influence some steels.\nCare must be taken to avoid galvanic corrosion between the braze and the base metal, and especially between dissimilar base metals being brazed together. Formation of brittle intermetallic compounds on the alloy interface can cause joint failure. This is discussed more in-depth with solders.\nThe potentially detrimental phases may be distributed evenly through the volume of the alloy, or be concentrated on the braze-base interface. A thick layer of interfacial intermetallics is usually considered detrimental due to its commonly low fracture toughness and other sub-par mechanical properties. In some situations, e.g. die attaching, it however does not matter much as silicon chips are not typically subjected to mechanical abuse.\nOn wetting, brazes may liberate elements from the base metal. For example, aluminium-silicon braze wets silicon nitride, dissociates the surface so it can react with silicon, and liberates nitrogen, which may create voids along the joint interface and lower its strength. Titanium-containing nickel-gold braze wets silicon nitride and reacts with its surface, forming titanium nitride and liberating silicon; silicon then forms brittle nickel silicides and eutectic gold-silicon phase; the resulting joint is weak and melts at much lower temperature than may be expected.\nMetals may diffuse from one base alloy to the other one, causing embrittlement or corrosion. An example is diffusion of aluminium from aluminium bronze to a ferrous alloy when joining these. A diffusion barrier, e.g. a copper layer (e.g. in a trimet strip), can be used.\nA sacrificial layer of a noble metal can be used on the base metal as an oxygen barrier, preventing formation of oxides and facilitating fluxless brazing. During brazing, the noble metal layer dissolves in the filler metal. Copper or nickel plating of stainless steels performs the same function.\nIn brazing copper, a reducing atmosphere (or even a reducing flame) may react with the oxygen residues in the metal, which are present as cuprous oxide inclusions, and cause hydrogen embrittlement. The hydrogen present in the flame or atmosphere at high temperature reacts with the oxide, yielding metallic copper and water vapour, steam. The steam bubbles exert high pressure in the metal structure, leading to cracks and joint porosity. Oxygen-free copper is not sensitive to this effect, however the most readily available grades, e.g. electrolytic copper or high-conductivity copper, are. The embrittled joint may then fail catastrophically without any previous sign of deformation or deterioration.\nFlux.\nUnless brazing operations are contained within an inert or reducing atmosphere environment (i.e. Nitrogen), a flux such as borax is required to prevent oxides from forming while the metal is heated. The flux also serves the purpose of cleaning any contamination left on the brazing surfaces. Flux can be applied in any number of forms including flux paste, liquid, powder or pre-made brazing pastes that combine flux with filler metal powder. Flux can also be applied using brazing rods with a coating of flux, or a flux core. In either case, the flux flows into the joint when applied to the heated joint and is displaced by the molten filler metal entering the joint. Excess flux should be removed when the cycle is completed because flux left in the joint can lead to corrosion, impede joint inspection, and prevent further surface finishing operations. Phosphorus-containing brazing alloys can be self-fluxing when joining copper to copper. Fluxes are generally selected based on their performance on particular base metals. To be effective, the flux must be chemically compatible with both the base metal and the filler metal being used. Self-fluxing phosphorus filler alloys produce brittle phosphides if used on iron or nickel. As a general rule, longer brazing cycles should use less active fluxes than short brazing operations.\nAtmosphere.\nAs brazing work requires high temperatures, oxidation of the metal surface occurs in an oxygen-containing atmosphere. This may necessitate the use of an atmospheric environment other than air. The commonly used atmospheres are:\nPreforms.\nA brazing preform is a high quality, precision metal stamping used for a variety of joining applications in manufacturing electronic devices and systems. Typical brazing preform uses include attaching electronic circuitry, packaging electronic devices, providing good thermal and electrical conductivity, and providing an interface for electronic connections. Square, rectangular and disc shaped brazing preforms are commonly used to attach electronic components containing silicon dies to a substrate such as a printed circuit board. Rectangular frame shaped preforms are often required for the construction of electronic packages while washer shaped brazing preforms are typically utilized to attach lead wires and hermetic feed-throughs to electronic circuits and packages. Some preforms are also used in diodes, rectifiers, optoelectronic devices and components packaging.\nSafety.\nBrazing may entail exposure to hazardous chemical fumes. The National Institute for Occupational Safety and Health in the United States recommends that exposure to these fumes is controlled to levels below the allowed exposure limit.", "Engineering,_Manufacturing": 1.0000007153, "qwen": "Yes"}
{"id": "47067520", "revid": "10248457", "url": "https://en.wikipedia.org/wiki?curid=47067520", "title": "Transfer stamping", "text": "Sheet metal forming in medium-high volume production environments is often completed through the use of a Transfer Press operating a number of dies as a complete system. Each die in the system is responsible for adding more shape to the part until the metal work piece attains its final shape. What makes transfer stamping unique is that a single press operates a number of tools, the movement of the sheet metal work piece from one operation to the next is performed by automation either built into the press or onto the dies. With each closing of the press the entire system of tools will close, each performing its designed work to the sheet metal. Upon opening the built in transfer mechanism moves the workpiece from one operation to the next in the sequence. \nIn the past these operations may have been performed using individual presses and the workpieces may have been moved from press to press, and die to die, by hand. As Automation improved hand loading was replaced by pick and place automation and by robots. The transfer press is a natural extension of this practice, simplifying the operation by having all tools in a single large press and using automation which is specifically designed for the press operations.\nTransfer mechanisms.\nTri-axis transfer.\nNamed for the movement of the transfer mechanism, tri-axis transfer mechanisms motion is defined by the three (3) axes of movement made by the part manipulators each press stroke. On the press downstroke the automation which will likely be holding the work piece will lower the work piece to the tool and retract to leave the part on the tool. At the bottom of the stroke the automation mechanism in the retracted state will cycle backward one pitch to position itself adjacent to the next workpiece. As the press cycles upward the part manipulators will index inward to pick up the next work piece, continuing upward following the press ram, then indexing forward to next station. As the press reaches the top of its stroke, the process repeats. The three axes of motion are up-down, in-out, and forward-back. \nCross-bar transfer.\nWith a cross bar transfer mechanism, the in-out axes of movement is constrained by an automation bar spanning the die space. Commonly mounted with suction cups, this cross bar will pick the workpiece up from above and release the part, dropping it into place at the next station. With only two axes of motion and the automation spanning the die space, the cross bar transfer mechanism must \"dwell\" between adjacent tools between each press stroke.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "47069322", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=47069322", "title": "Kudo3d", "text": "Kudo3D, based in Dublin, California, manufactures professional desktop 3D printers. Its Titan 1 and Titan 2 3D printer use a proprietary passive self-peeling technology, making it one of the leading professional high-resolution stereolithography printers. This technology allows both the Titan 1 and Titan 2 to be used in printing for various applications.\nHistory.\nIn 2012, founder Tedd Syao started creating the Titan 1 and developed the passive self-peeling technology from his garage. Shortly after, Tedd Syao and Jonathan Cheung, both UC Berkeley's Haas School of Business alumni, co-founded Kudo3D.\nKudo3D launched its Kickstarter in May 2014 that was funded within 2 minutes. After its successful campaign and delivery, Kudo3D continued to grow. The company has now expanded to two locations: Pleasanton, California, and Hsinchu, Taiwan.\nTitan 1.\nThe Titan 1 was constructed using modular design, utilizing industrial and consumer-grade components. The printer uses Texas Instrument's DLP technology as its light source and printing time is further reduced as entire layers of resin can be cured at one time. Other components include an industrial grade linear stage module, an open-source controlling circuit, a stepping motor, a fast leveling build platform, and Kudo3D's patented flexible PSP (Passive self-peeling) resin container lined with Teflon to extend container lifetime.\nThird Party Resin.\nThe Titan 1 prints using third party resin. Titan 1 is most compatible with: MakerJuice G+, Spot A's Hard & Tough for High Resolution, Spot A's Flexible Resin, 3D Materials’ Castable and ABS resins.\nApplication.\nThe Titan 1's ability to print a wide range of sizes makes it versatile and usable for different applications. The Titan 1 grows extremely high resolutions prints, which is ideal for printing jewelry, miniatures, and research models. The Titan 1 has printed tissue scaffold for the biomedical research department at CCNY that is only 1mm by 2mm. However, it also possesses the ability to print larger items, making the Titan 1 perfect for art, architectural, engineering, and prototyping applications.\nTitan 2.\n2 years after the successful Kickstarter campaign, Kudo3D released their second generation 3D printer, the Titan 2. The Titan 2 promises a more reliable 3D printer with advanced controls, making it more user-friendly than its predecessor. With a built-in Raspberry Pi and web-based controls, the Titan 2 is compatible with any computer, tablet, or smartphone device.\nThe Titan 2 incorporates all of the technology from the Titan 1, including the patented PSP resin container. In addition, the Titan 2 comes in 2 different cover colors, the Ruby Red and Green Emerald.\nTitan 2 HR.\nIn November 2016, Kudo3D released a \"spin-off\" of the Titan 2 3D printer. Named Titan 2 HR, this printer is capable of printing objects at 23 microns XY resolution. This capability makes it especially appealing to people who would like to print high-resolution, fine prints, such as jewelers.\nBean.\nMarking the third anniversary of the initial Kickstarter launch, Kudo3D launched their new printer once again on Kickstarter. Dubbed the Bean, this compact 3D printer was created to solve the consumer's desire for a high resolution, low cost 3D printer. The Bean was able to reach their goal of $50,000 within 2 minutes and $100,000 in 3 minutes. The Bean 3D printer is a LCD SLA 3D printer, meaning it uses a LCD to project images slices onto the resin container.\nKudo3d offers seven proprietary resins (not compatible with Titan 1 or Titan 2) for the Bean; It can also use third party resins.\nPSP Technology.\nPassive self-peeling (PSP) technology is a patented, bottom-up, SLA technology, which was created by Kudo3D to minimize the separation force between the cured layers and the resin. PSP employs a flexible resin container consisting of 5 different materials, which work together to aid in reducing the separation force. It ensures that features as fine as a strand of hair and larger objects, up to 10 inches tall, can be printed with the same machine.\nThis technology allows prints to require fewer supports, minimizing cleanup and scarring. It also enables features as fine as a strand of hair and larger objects, up to 10 inches tall, to be printed by the same machine while maintaining staggering resolution and impressive speeds.\nPatent Approval.\nOn September 27, 2016, Kudo3D received approval of the PSP (passive self-peeling) technology from the US Patent and Trademark Office.", "Engineering,_Manufacturing": 0.9997988343, "qwen": "Yes"}
{"id": "6851511", "revid": "7852030", "url": "https://en.wikipedia.org/wiki?curid=6851511", "title": "High stock removal", "text": "High stock removal is a technological process with the goal of removing large amounts of material. The quantity of material which can be removed by a specific process depends on the material properties and the machining tool used.\nMaterials.\nThe stock removal rate is largely a function of the material's properties. This is expressed as the machinability of a material: the ease or difficulty of machining a particular material. The machinability of materials varies greatly; for instance, aluminium and magnesium have high machinability compared to titanium and other special metals.\nSpecific energy.\nOne way of quantifying the machinability of a material is to measure specific energy (e): this is the amount of energy required to cut a given volume of work material (kWh/mm3), and varies with material properties.\nNew materials.\nNew materials are continuously developed to address the extreme demands of market segments such as petrochemical and aerospace. Metallurgical advances have produced a wide range of high-performance materials (e.g. titanium and high-nickel alloys), but a consequence of their attractive properties is often that they are difficult to machine.\nTemperature rising.\nThe specific cutting energy needed for ‘difficult to machine’ materials can be extremely high. Especially in high stock removal applications, there are problems with thermal load in the work material. An increase of the work material temperature can lead to deterioration of the work material surface integrity, resulting in metallurgical damages like micro-cracks, residual stresses and work hardening. Excessive heat also dramatically shortens tool life.\nHigh stock removal machine tools.\nThe energy required to remove large amounts of material depends on the properties of the working material (specific energy) as well as the technological process used.\nTechnologies.\nSeveral technologies are capable of removing substantial amounts of material. Among them are: sawing, turning, broaching, milling and grinding. Turning and milling are the most popular machining technologies; turning is mainly used for round products (though a specialized variant called whirling can modulate the turning axis to produce non-round shapes), whereas milling has a broad range of applications. Certain ‘difficult to machine’ materials like titanium, stainless steels, and exotic high-nickel alloys can be challenging to process when high stock removal is the goal, due to local heat generation at the cutting edge and the difficulty in removing it. These challenges can be mitigated, however, by strategies such as high-volume flood coolant, specialized cutting tool geometries, optimized speed and feed settings, and tool coatings like AlTiCN which tend to divert heat into the chip, away from the cutting tool.\nGrinding.\nTraditionally bonded abrasives are used for stock removal. To remove substantial amounts of material in a grinding process, vertical segment grinders are used. These machines work with a rotating disc with abrasive segments, against which the work material is pressed with the aid of a rotating or reciprocating table. These technologies require significantly greater power than other grinding methods, up to . Some major manufactures of these machines are Blanchard, Mattison, Göckel and Reform.\nBelt grinding.\nGrinding with coated abrasives has recently become a viable alternative for high stock removal through developments in machine tool and grinding belt technology.\nBelt grinding with coated abrasives can be an attractive process because the large surface area of the recirculating belt tends to carry away heat and prevent local hot spots. The productivity of this technology is, in many cases, three times that of rotary or reciprocating vertical grinders. As a result, belt grinding is replacing traditional grinding technologies in the field of the specialty metal processing. ", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "6852657", "revid": "21857263", "url": "https://en.wikipedia.org/wiki?curid=6852657", "title": "Belt grinding", "text": "Belt grinding is an abrasive machining process used on metals and other materials. It is typically used as a finishing process in industry. A belt, coated in abrasive material, is run over the surface to be processed in order to remove material or produce the desired finish.\nApplications.\nBelt grinding is a versatile process suitable for all kinds of different applications. There are three different applications of the belt grinding technology:\nGrinding methods.\nWide belt grinding is a familiar process in industry as well as home applications. There are several basic methods for belt grinding:\nIn general there are three basic elements of the belt-grinding machine: work rest support, grinding head and a regulating head. These components differ for all the methods but in general the workpiece is pressed between the grinding head and the rest support. The objective of the regulating head is to coordinate the belt pressure. \nWide belt grinding.\nOne of the most common methods is wide belt grinding.\nThe belt grinding process is variable by adjusting certain parameters such as belt speed, grinding pressure, feed speed, durometer of the contact drum, size of the contact drum and the abrasive belt that is used. The machines can be made for wet or dry operation. Furthermore, a wide belt grinding machine can be constructed with single or multiple heads. The first head is used for coarse grinding and the next heads gradually make a finer finish. Wide belt grinding is also used as a high stock removal method for special metals (e.g. stainless steel, titanium, and nickel alloys).\nChanging variables.\nThere are several objectives possible for grinding with coated abrasives. Among them are the right application (e.g. finish or stock removal), time saving and efficiency of the abrasive tool. \nTo achieve the above objectives, it is essential to look in more detail to the variables which affect them. These include the work material properties, the grit and abrasive type of the grinding belt, belt speed, belt sequences, contact wheel hardness and diameter, serration, type of lubricant (or dry) and grinding pressure. Changing these variables will affect the performances of the belt grinding process. \nIn the wide belt method, a contact wheel supports the abrasive belt. The selection of the contact wheel and abrasive to match the grinding parameters required for a specific operation is very critical. Stock removal generally requires a harder, serrated rubber contact wheel, and coarse grade ceramic abrasives. Finishing generally requires the use of a smooth faced contact wheel and fine grade abrasives.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "6861318", "revid": "20394442", "url": "https://en.wikipedia.org/wiki?curid=6861318", "title": "Fusible core injection molding", "text": "Fusible core injection molding, also known as lost core injection molding, is a specialized plastic injection molding process used to mold internal cavities or undercuts that are not possible to mold with demoldable cores. Strictly speaking the term \"fusible core injection molding\" refers to the use of a fusible alloy as the core material; when the core material is made from a soluble plastic the process is known as soluble core injection molding. This process is often used for automotive parts, such as intake manifolds and brake housings, however it is also used for aerospace parts, plumbing parts, bicycle wheels, and footwear.\nThe most common molding materials are glass-filled nylon 6 and nylon 66. Other materials include unfilled nylons, polyphenylene sulfide, glass-filled polyaryletherketone (PAEK), glass-filled polypropylene (PP), rigid thermoplastic urethane, and elastomeric thermoplastic polyurethane.\nHistory.\nThe first patent for this type of molding process was taken out in 1968, however it was rarely used until the 1980s. That is when the automotive industry took interest in it to develop intake manifolds.\nProcess.\nThe process consists of three major steps: casting or molding a core, inserting the core into the mold and shooting the mold, and finally removing the molding and melting out the core.\nCore.\nFirst, a core is molded or die cast in the shape of the cavity specified for the molded component. It can be made from a low melting point metal, such as a tin-bismuth alloy, or a polymer, such as a soluble acrylate. The polymer has approximately the same melting temperature as the alloy, however the alloy ratios can be modified to alter the melting point. Another advantage to using a metal core is that multiple smaller cores can be cast with mating plugs and holes so they can be assembled into a final large core.\nOne key in casting metal cores is to make sure they do not contain any porosity as it will induce flaws into the molded part. In order to minimize porosity the metal may be gravity cast or the molding cavity may be pressurized. Another system slowly rocks the casting dies as the molding cavity fills to \"shake\" the air bubbles out.\nThe metal cores can be made from a number of low melting point alloys, with the most common being a mixture of 58% bismuth and 42% tin, which is used for molding nylon 66. One of the main reasons it is used is because it expands as it cools which packs the mold well. Other alloys include tin-lead-silver alloys and tin-lead-antimony alloys. Between these three alloy groups a melting point between 98 and 800 °F (37–425 °C) can be achieved.\nPolymer cores are not as common as metal cores and are usually only used for moldings that require simple internal surface details. They are usually thick hollow cross-sections that are molded in two halves and are ultrasonically welded together. Their greatest advantage is that they can be molded in traditional injection molding machines that the company already has instead of investing into new die casting equipment and learning how to use it. Because of this polymer core materials are most adventitious for small production runs that cannot justify the added expense of metal cores. Unfortunately it is not as recyclable as the metal alloys used in cores, because 10% new material must be added with the recycled material.\nMolding.\nIn the second step, the core is then inserted into the mold. For simple molds this is as simple as inserting the core and closing the dies. However, more complex tools require multiple steps from the programmed robot. For instance, some complex tools can have multiple conventional side pulls that mate with the core to add rigidity to the core and reduce the core mass. After the core is loaded and the press closed the plastic is shot.\nMelt-out.\nIn the final step, the molded component and core are both demolded and the core is \"melted-out\" from the molding. This is done in a \"hot bath\", via induction heating, or through a combination of the two. Hot baths usually use a tub filled with glycol or Lutron, which is a phenol-based liquid. The bath temperature is slightly higher than that of the core alloy’s melting point, but not so high that it damages the molding. In typical commercial applications the parts are dipped into the hot bath via an overhead conveyor. The advantage to using a hot bath is that it is simpler than induction heating and it helps cure thermoset moldings. The disadvantage is that it is uneconomically slow at a cycle time of 60 to 90 minutes and it poses environmental cleanup issues. Typically the hot bath solution needs cleaning or replacement every year or every half year when used in combination with induction heating.\nFor thermoplastic moldings induction heating of the core metal is required, otherwise the prolonged heat from a hot bath can warp it. Induction heating reduces the melt-out time to one to three minutes. The disadvantage is that induction heating does not remove all of the core material so it must then be finished off in a hot bath or be brushed out. Another disadvantage is that the induction coils must be custom built for each molding because the coils must be from the part. Finally, induction heating systems cannot be used with moldings that have brass or steel inserts because the induction heating process can destroy or oxidize the insert.\nFor complex parts it can be difficult to get all of the core liquid to drain out in either melt-out process. In order to overcome this the parts may be rotated for up to an hour. Liquid core metal collects on the bottom of the heated bath and is usable for a new core.\nEquipment.\nTraditional horizontal injection molding machines have been used since the mid-1980s, however loading and unloading cores are difficult so two robots are required. Moreover, the cycle time is quite long, approximately 28 seconds. These problem are overcome by using rotary or shuttle action injection molding machines. These types of machines only require one robot to load and unload cores and have a 30% shorter cycle time. However, these types of machines cost approximately 35% more than horizontal machines, require more space, and require two bottom molds (because one is in the machine during the cycle and the other is being unloaded and loaded with a new core), which adds approximately 40% to the tooling cost. For small parts, horizontal injection molding machines are still used, because the core does not weigh enough to justify the use of a rotary machine.\nFor four-cylinder manifolds a 500-ton press is required; for a six- to eight-cylinder manifold a 600- to 800-ton press is required.\nAdvantages and disadvantages.\nThe greatest advantage of this process is its ability to produce single-piece injection moldings with highly complex interior geometries without secondary operations. Similarly shaped objects are usually made from aluminum castings, which can weigh 45% to 75% more than a comparable molding. The tooling also lasts longer than metal casting tooling due to the lack of chemical corrosion and wear. Other advantages include:\nTwo of the major disadvantages of this process are the high cost and long development time. An automotive part can take four years to develop; two years in the prototype stage and two years to reach production. Not all products take this long, for instance a two-way valve produced by Johnson Controls only took 18 months. The initial cost can be as much as US$8 million to produce a four-cylinder engine manifold. However, computer flow analysis has helped reduce lead time and costs.\nOne of the difficulties that result from these long development times and high costs is making accurate cores repeatably. This is extremely important because the core is an integral part of the mold, so essentially each shot is into a new mold cavity. Another difficulty is keeping the core from melting when the plastic is shot into the mold, because the plastic is approximately twice the melting temperature of the core material. A third difficulty is the low strength of the core. Hollow plastic cores can collapse if too much pressure is used in the shot plastic. Metal cores (with low melting temperatures) are solid so they cannot collapse, but are only 10% as strong as steel cores so they can distort. This is especially a problem when molding manifolds, because the waviness of the core can be detrimental to the airflow within the runners.\nAnother disadvantage is the need for a large space to house the injection molding machines, casting machines, melt-out equipment, and robots.\nBecause of these disadvantages, some moldings that would be made via this process are instead made by injection molding two or more parts in a traditional injection molding machine and then welding them together. This process is less expensive and requires much less capital, however it imparts more design constraints. Because of the design constraints, sometimes parts are made with both processes to gain the advantages of both.\nApplication.\nThe application of the fusible core process is not limited just to the injection of thermoplastics, but with corresponding core alloys also to thermosetting plastic molding materials (duroplast). The fusible core process finds application, for example, for injection molded passenger car engine intake manifolds. By modifying the equipment, small molded parts like valves or pump housings can be manufactured, as the manufacture of the fusible cores and the injected parts can be carried out on an injection molding machine.", "Engineering,_Manufacturing": 1.0000014305, "qwen": "Yes"}
{"id": "6864677", "revid": "1163815449", "url": "https://en.wikipedia.org/wiki?curid=6864677", "title": "Melt spinning", "text": "Melt spinning is a metal forming technique that is typically used to form thin ribbons of metal or alloys with a particular atomic structure.\nSome important commercial applications of melt-spun metals include high-efficiency transformers (Amorphous metal transformer), sensory devices, telecommunications equipment, and power electronics.\nA typical melt spinning process involves casting molten metal by jetting it onto a rotating wheel or drum, which is cooled internally, usually by water or liquid nitrogen. The molten material rapidly solidifies upon contact with the large, cold surface area of the drum. The rotation of the drum constantly removes the solidified product while exposing new surface area to the molten metal stream, allowing for continuous production. The resulting ribbon is then directed along the production line to be packaged or machined into further products.\nThe cooling rates achievable by melt spinning are on the order of 104–106 Kelvins per second (K/s). Consequently, melt spinning is used to develop materials that require extremely high cooling rates in order to form, such as metallic glasses. Due to their rapid cooling, these products have a highly disordered atomic structure which gives them unique magnetic and physical properties (\"see amorphous metals\").\nSeveral variations to the melt spinning process provide specific advantages. These processes include planar flow casting, twin roll melt spinning, and auto ejection melt spinning.\nOriginating with Robert Pond in a series of related patents from 1958 to 1961 (US Patent Nos. 2825108, 2910744, and 2976590), the current concept of the melt spinner was outlined by Pond and Maddin in 1969. At first, the liquid was quenched on the inner surface of a drum. Liebermann and Graham further developed the process as a continuous casting technique by 1976, this time on the drum's outer surface. The process can continuously produce thin ribbons of material, with sheets several inches in width commercially available.\nProcess.\nIn melt spinning, the alloy or metal is first melted in a crucible. Then, an inert gas, usually argon, is used to jet the molten material out of a nozzle located on the underside of the crucible. The resulting stream of liquid is directed onto the outer circumferential surface of a rotating wheel or drum which is cooled internally. The drum's outer surface is located extremely close to the nozzle but does not touch it. Generally, the velocity of the drum's surface must be between 10 m/s and 60 m/s in order to avoid the formation of globules (droplets) or breaking the ribbon respectively. Once the stream contacts the drum's surface, a small puddle of melt (molten material) is formed. Due to the low viscosity of the melt, the shear forces generated by the relative movement of the drum's surface underneath the melt only extend a few microns into the puddle. In other words, only a small amount of the puddle is affected by the friction from the rotation of the drum. Consequently, as the drum spins, most of the melt puddle remains held between the nozzle and the drum by surface tension. However, the melt on the very bottom of the puddle, which is in direct contact with the drum, rapidly solidifies into a thin ribbon. The solidified ribbon is carried away from under the nozzle on the drum's surface for up to 10° of rotation before centrifugal force from the drum's rotation ejects it.\nThis process occurs continuously, so as solidified material is removed from underneath the puddle of melt, more liquid material is added to the puddle from the nozzle.\nVarying factors.\nThere are many factors at play in even a basic melt spinning process. The quality and dimensions of the product are determined by how the machine is operated and configured. Consequently, there are many studies exploring the effects of variations in the melt spinner's configuration on specific alloys. For example, here is an article about the specific conditions that were found to work well for melt spinning Fe-B and Fe-Si-B alloys.\nIn general, melt spinners will run with some variation in the following variables depending on the desired product.\nSince every material acts differently, the exact cause-effect relationship between each of these variables and the resulting ribbon is usually determined experimentally. Other less commonly adjusted variables exist, but their effects on the final ribbon dimensions and structure aren't all documented.\nDifferent mathematical models of numerical simulation were developed to obtain relevant characteristics of the ribbons according to the tangential speeds of wheel rotation, the nozzle gap, and the ejection pressure.\nModifications.\nDifferent processes and techniques have been developed around melt spinning which offer advantages to the industrial applications and product consistency.\nPlanar Flow Casting.\nPlanar Flow Casting (PFC) is a commonly used melt spinning process for the industrial fabrication of wide metallic glass sheets. In this process, the primary modification is that a much wider nozzle is used to eject the melt from the crucible. As a result, the melt puddle covers a larger area of the drum, which in turn forms a larger area of ribbon. PFC is commonly cast in a vacuum to avoid oxidation of the molten material, which would affect the quality of the resulting product. Ribbons up to 200 mm wide have been industrially achieved using PFC.\nTwin Roll Melt Spinning.\nIn Twin Roll Melt Spinning two rollers or drums are used instead of one. The rollers are placed side by side, and rotated such that the one to the left spins clockwise, and the one on the right spins counter-clockwise. This configuration results in material passing between the rollers being pulled down. The melt is jetted between the rollers where it is cooled and ejected as a ribbon. The advantage of twin-roll melt spinning is that it gives a high degree of control over the thickness of the resulting ribbon. With a single roller, controlling ribbon thickness is complicated involving close control over the flow rate of the melt, rotational speed of the wheel, and temperature of the melt. With the twin roller setup, a particular and consistent thickness can be achieved by simply changing the distance between the rollers.\nTo date, twin roll melt spinning is still limited almost exclusively to laboratory scales.\nAuto Ejection Melt Spinning.\nAuto Ejection Melt Spinning (AEMS) describes a type of melt spinning where ejection of the melt occurs as soon as it has liquefied, eliminating the need for a technician to manually control the flow rate, temperature, and/or release timing of the melt stream.\nThis modification allows for a much higher ribbon consistency between runs, and a greater level of automation in the process.\nProduct.\nMelt spinning is used to manufacture thin metal sheets or ribbons that are near amorphous or non-crystalline. The unique resulting electric and magnetic properties of melt-spun metals are a consequence of this structure as well as the composition of the alloy or metal that was used to form the ribbon.\nStructure.\nNormally, when a metallic material cools, the individual atoms solidify in strong, repeating patterns to form a crystalline solid. However, in melt spinning, the melt is quenched (cooled) so rapidly that the atoms don't have time to form these ordered structures before they completely solidify. Instead, the atoms are solidified in positions resembling their liquid state. This physical structure gives rise to the magnetic and electric properties of amorphous metals.\nElectric and Magnetic Properties.\nThe amorphous material produced by melt spinning is considered a soft magnet. That is to say that their natural coercivity is less than 1000 Am-1, which means that the metal's magnetism is more responsive to outside influences and as a result can be easily switched on and off. This makes amorphous metals particularly useful in applications requiring the repeated magnetization and demagnetization of a material in order to function. Certain amorphous alloys also provide the ability to enhance and or channel flux created by electrical currents, making them useful for magnetic shielding and insulation.\nThe exact magnetic properties of each alloy depend mostly on the atomic composition of the material. For example, nickel-iron alloys with a lower amount of nickel have a high electrical resistance, while those with a higher percentage of nickel have a high magnetic permeability.", "Engineering,_Manufacturing": 0.999982357, "qwen": "Yes"}
{"id": "63005915", "revid": "46135219", "url": "https://en.wikipedia.org/wiki?curid=63005915", "title": "Material removal rate", "text": "Material removal rate (MRR) is the amount of material removed per time unit (usually per minute) when performing machining operations such as using a lathe or milling machine. The more material removed per minute, the higher the material removal rate. The MRR is a single number that enables you to do this. It is a direct indicator of how efficiently you are cutting, and how profitable you are. MRR is the volume of material removed per minute. The higher your cutting parameters, the higher the MRR.\nPhrased in another way, the MRR is equal to the volume of residue formed as a direct result of the removal from the workpiece per unit of time during a cutting operation.\nThe material removal rate in a work process can be calculated as the depth of the cut, times the width of the cut, times the feed rate. The material removal rate is typically measured in cubic centimeters per minute (cm3/min).", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "14326527", "revid": "1153724003", "url": "https://en.wikipedia.org/wiki?curid=14326527", "title": "Flying probe", "text": "In the manufacture of electronic printed circuit boards, flying probes are used for testing both bare circuit boards and boards loaded with components. Flying probes were introduced in the late 1980’s. Flying probes can be found in many manufacturing and assembly operations. A flying probe tester uses one or more test probes to make contact with the circuit board under test; the probes are moved from place to place on the circuit board to carry out tests of multiple conductors or components. Flying probe testers are an alternative to bed of nails testers, which use multiple contacts to simultaneously contact the board and which rely on electrical switching to carry out measurements. \nOne limitation in flying probe test methods is the speed at which measurements can be taken; the probes must be moved to each new test site on the board, and then a measurement must be completed. Bed-of-nails testers touch each test point simultaneously and electronic switching of instruments between test pins is more rapid than movement of probes.\nLoaded board in-circuit test.\nIn the testing of printed circuit boards, a flying probe test or fixtureless in-circuit test (FICT) system may be used for testing low to mid volume production, prototypes, and boards that present accessibility problems. A traditional \"bed of nails\" tester for testing a PCB requires a custom fixture to hold the PCBA and the Pogo pins which make contact with the PCBA. In contrast, FICT uses two or more flying probes, which may be moved based on software instruction. The flying probes are electro-mechanically controlled to access components on printed circuit assemblies (PCAs). The probes are moved around the board under test using an automatically operated two-axis system, and one or more test probes contact components of the board or test points on the printed circuit board.\nThe main advantage of flying probe testing is the substantial cost of a bed-of-nails fixture, costing on the order of US $20,000, is not required. The flying probes also allow easy modification of the test fixture when the PCBA design changes. FICT may be used on both bare or assembled PCB's. However, since the tester makes measurements serially, instead of making many measurements at once, the test cycle may become much longer than for a bed-of-nails fixture. A test cycle that may take 30 seconds on such a system, may take an hour with flying probes. Test coverage may not be as comprehensive as a bed of nails tester (assuming similar net access for each), because fewer points are tested at one time. ", "Engineering,_Manufacturing": 0.9991738796, "qwen": "Yes"}
{"id": "22750410", "revid": "14730724", "url": "https://en.wikipedia.org/wiki?curid=22750410", "title": "Zonda Telecom", "text": "Zonda Telecom is a Mexican telecommunications company founded in Guadalajara, Jalisco in 1968 as a television manufacturer.\nThis company has several manufacturing plants in the Guadalajara Metropolitan Area, which manufacture its own products as well as electronic products for other companies. This makes Zonda an OEM.\nIn 2002, Zonda Telecom entered the mobile phone market becoming the first Mexican company to design its own Mobile Phones. Zonda has also produced communications systems and communication subsystems and for the Mexican military.\nModels.\nBelow is a partial list of some of Zonda Telecoms mobile phone models.", "Engineering,_Manufacturing": 0.9975938797, "qwen": "Yes"}
{"id": "22751670", "revid": "1170395242", "url": "https://en.wikipedia.org/wiki?curid=22751670", "title": "Balatonfüredi KSE", "text": "Balatonfüredi Kézilabda Sport Egyesület is a Hungarian team handball club from Balatonfüred, that currently plays in the Nemzeti Bajnokság I. The team won promotion to the top division in 2007 and achieved their best ever result in 2009 by finishing fifth. In the 2009–2010 Hungarian Cup campaign the club finished third, but as the two finalists, MKB Veszprém KC and Pick Szeged already secured their places in the EHF Champions League, BKSE got the right to represent Hungary in the EHF Cup Winners' Cup next season.\nCrest, colours, supporters.\nKit manufacturers and shirt sponsor.\nThe following table shows in detail Balatonfüredi KSE kit manufacturers and shirt sponsors by year:\nKits.\n \nHonours.\nIndividual awards.\nDomestic.\nNemzeti Bajnokság I Top Scorer\nEuropean competition.\nEHF Cup Winners' Cup: from the 2012–13 season, the men's competition was merged with the EHF Cup.EHF Cup: It was formerly known as the IHF Cup until 1993. Also, starting from the 2012–13 season the competition has been merged with the EHF Cup Winners' Cup. The competition will be known as the EHF European League from the 2020–21 season.", "Engineering,_Manufacturing": 0.9984602928, "qwen": "Yes"}
{"id": "2657310", "revid": "18054835", "url": "https://en.wikipedia.org/wiki?curid=2657310", "title": "Sprue (manufacturing)", "text": "A sprue is the vertical passage through which liquid material is introduced into a mold and it is a large diameter channel through which the material enters the mold. It connects the pouring basin to the runner. In many cases it controls the flow of material into the mold. During casting or molding, the material in the sprue will solidify and need to be removed from the finished part. It is usually tapered downwards to minimize turbulence and formation of air bubbles.\nCasting.\nIn casting, a sprue is the passage through which a molten material is introduced into a mold, and the term also refers to the excess material which solidifies in the sprue passage.\nFunction.\nSprues can serve as filters, as heat sinks, and as feeders. Bronze, in particular, has a high shrinkage rate as it is cooling. A sprue is tapered with its bigger end at the top to receive the liquid metal, the smaller end is connected to the runner.\nSprue design.\nThe design of the sprue gating and runner is also essential for casting. The design can incorporate either bottom or vertical gating.\nFor bottom gating\nwhere:\nThis equation may change if the height of gating is equal to height of casting material.\nThen the equation will be:\nor, simplified,\nwhere:\nInjection molding.\nIn injection molding, sprue refers to the passage through which a liquid material (such as polystyrene or polyvinyl chloride) flows into a die, where the material solidifies to form parts. \"Sprue\" also refers to the material that solidifies in these passages, forming a framework that attaches the parts in a roughly planar arrangement.\nSprues, runners, and gates.\nSome moldmakers distinguish the sprue, the gate, and the runner. The sprue is a large-diameter channel through which plastic flows, usually around the edges of the part or along straight lines. The runner is a smaller channel from the sprue to the individual part. An analogy may be found in a water system that employs a water main (sprue) and smaller pipes (runners) to individual houses. The gate is the location at which the molten plastic enters the mold cavity and is often evidenced by a small nub or projection (the \"gate mark\") on the molded piece. \nMany scale-model kits are made from injection-molded plastic. Hobbyists typically remove the parts of a model kit from the runner using a sharp craft knife or razor saw. The sprues usually form a rectangle with the runners and parts inside which makes them easier to box.\nModel makers sometimes use sprues or runners as raw material to fabricate additional parts, such as railings on model ships, antenna wires on airplanes, or greebles on fictional spacecraft.\nSprues in model kits often include engravings to identify the parts by number.", "Engineering,_Manufacturing": 0.9990382195, "qwen": "Yes"}
{"id": "2133869", "revid": "6289403", "url": "https://en.wikipedia.org/wiki?curid=2133869", "title": "Living hinge", "text": "A living hinge or integral hinge is a thin flexible hinge (flexure bearing) made from the same material as the two rigid pieces it connects.\nDescription.\nA living hinge or integral hinge is a thin flexible hinge (flexure bearing). It is made from the same material as the two rigid pieces it connects. It is typically thinned or cut to allow the rigid pieces to bend along the line of the hinge. The minimal friction and very little wear in such a hinge makes it useful in the design of microelectromechanical systems, and the low cost and ease of manufacturing makes them quite common in clamshell containers and other disposable, recyclable packaging.\nPlastic.\nPlastic living hinges are typically manufactured in an injection molding operation that creates all three parts at one time as a single piece, and if correctly designed and constructed, it can remain functional over the life of the part. Thermoforming can also produce hinged products. Polyethylene and polypropylene are considered to be the best resins for living hinges, due to their excellent fatigue resistance. Acrylonitrile butadiene styrene (ABS) is also common.\nWood.\nA variant on the kerf bend can be used to create living hinges in laser cut wood. The technique is popular for making light-duty hinges with large radii. It is also possible to create a living wood joint by hand, but the result is less accurate.", "Engineering,_Manufacturing": 0.9999673367, "qwen": "Yes"}
{"id": "39052461", "revid": "25112844", "url": "https://en.wikipedia.org/wiki?curid=39052461", "title": "Virtual home design software", "text": "Virtual home design software is a type of computer-aided design software intended to help architects, designers, and homeowners preview their design implementations on-the-fly. These products differ from traditional homeowner design software and other online design tools in that they use HTML5 to ensure that changes to the design occur rapidly. This category of software as a service puts an emphasis on usability, speed, and customization.\nBackground.\nHomeowners, contractors, and architects use virtual home exterior design software to help visualize changes to designs. Since virtual home design suites that use HTML5 are able to rapidly propagate changes to the home design, users can A/B test designs much more efficiently than with previous iterations of online design software.\nVirtual home design software has found widespread usage among homeowners who have suffered property damage, as server-side, HTML5-based design software is ideal for homeowners who wish to see what certain products will look like on damaged areas of their houses.\nExamples.\nSeveral manufacturers use virtual home design software to display their products online. These companies that utilize virtual home design software include GAF Materials Corporation, James Hardie, Exterior Portfolio, and CertainTeed. Some companies, such as Design My Exterior, have built virtual home design software that is not limited to products or brands in order to allow for greater flexibility by the end-user. Design My Exterior also uses ImageMapster in order to generate a greater range of options with less processing time.\nLive Home 3D is a virtual home design software for Microsoft Windows and macOS.\nFuture applications.\nSeveral companies are experimenting with virtual reality for architecture. They design virtual homes and allow customers to walk around with the help of a VR headset (such as the Occulus Rift). This way, customers get a realistic, true-to-scale idea of the end result.", "Engineering,_Manufacturing": 0.997661531, "qwen": "Yes"}
{"id": "3242265", "revid": "35699", "url": "https://en.wikipedia.org/wiki?curid=3242265", "title": "Ink jet material deposition", "text": "Ink jet material deposition is an emerging manufacturing technique in which inkjet technology is used to deposit materials on substrates. The technique aims to eliminate fixed costs of production and reduce the amount of materials used.\nUses.\nAnything that is produced using traditional printing techniques is a candidate for ink jet material deposition. In addition, the precision available with ink jet technology may be required for some industrial applications. Examples include:", "Engineering,_Manufacturing": 0.9983000159, "qwen": "Yes"}
{"id": "2945851", "revid": "2414730", "url": "https://en.wikipedia.org/wiki?curid=2945851", "title": "Progressive stamping", "text": "Progressive Die is a metalworking method that can encompass punching, coining, bending and several other ways of modifying metal raw material, combined with an automatic feeding system.\nThe feeding system pushes a strip of metal (as it unrolls from a coil) through all of the stations of a progressive stamping die. Each station performs one or more operations until a finished part is made. The final station is a cutoff operation, which separates the finished part from the carrying web. The carrying web, along with metal that is punched away in previous operations, is treated as scrap metal. Both are cut away, knocked down (or out of the dies) and then ejected from the die set, and in mass production are often transferred to scrap bins via underground scrap material conveyor belts.\nThe progressive stamping die is placed into a reciprocating stamping press. As the press moves up, the top die moves with it, which allows the material to feed. When the press moves down, the die closes and performs the stamping operation. With each stroke of the press, a completed part is removed from the die.\nSince additional work is done in each \"station\" of the die, it is important that the strip be advanced very precisely so that it aligns within a few thousandths of an inch as it moves from station to station. Bullet shaped or conical \"pilots\" enter previously pierced round holes in the strip to assure this alignment since the feeding mechanism usually cannot provide the necessary precision in feed length.\nProgressive stamping can also be produced on transfer presses. These are presses that transfer the components from one station to the next with the use of mechanical \"fingers\". For mass production of stamped parts which do require complicated in-press operations, it is always advisable to use a progressive press. One of the advantages of this type of press is the production cycle time. Depending upon the part, productions can easily run well over 800 parts/minute. One of the disadvantages of this type of press is that it is not suitable for high precision deep drawing which is when the depth of the stamping exceeds the diameter of the part. When necessary, this process is performed upon a transfer press, which run at slower speeds, and rely on the mechanical fingers to hold the component in place during the entire forming cycle. In the case of the progressive press, only part of the forming cycle can be guided by spring-loaded sleeves or similar, which result in concentricity and ovality issues and non uniform material thickness. \nOther disadvantages of progressive presses compared to transfer presses are: increased raw material input required to transfer parts, tools are much more expensive because they are made in blocks with very little independent regulation per station; impossibility to perform processes in the press that require the part leave the strip (example beading, necking, flange curling, thread rolling, rotary stamping etc.).\nThe dies are usually made of tool steel to withstand the high shock loading involved, retain the necessary sharp cutting edge, and resist the abrasive forces involved. \nThe cost is determined by the number of features, which determine what tooling will need to be used. Engineers keep the features as simple as possible to keep the cost of tooling to a minimum. Features that are close together produce a problem because it may not provide enough clearance for the punch, which could result in another station. It can also be problematic to have narrow cuts and protrusions.\nApplications.\nA representative example of the product of a progressive die is the lid of a beverage can. The pull tab is made in one progressive stamping process and the lid & assembly is made in another, the pull tab simultaneously feeding at a right angle into the lid & assembly process. Also various car brake calipers have plates that are bent into shape, possibly cut too using these methods.", "Engineering,_Manufacturing": 1.0000082254, "qwen": "Yes"}
{"id": "2952146", "revid": "13514090", "url": "https://en.wikipedia.org/wiki?curid=2952146", "title": "Hosiden", "text": " is a Japanese electronics company. It manufactures electronic components and devices and has a strong presence in the telecommunication and automotive industries prior to the consumer markets. It is headquartered in Yao, Osaka and has over 19 factories and more than 12,000 workers.\nIts products include connectors, memory card connectors, LCDs (Square and Rounded) and micro switches.\nFor its application in S-Video, the 4-pin Hosiden or Ushiden connector is often wrongly called mini-DIN connector. Hosiden Besson Limited was established in 1957, trading as A P Besson and Partner Limited in the UK, manufacturing earpieces for the National Health Service. It was sold to Crystalate Electronics in 1971 to form the Besson division, and as part of a manufacturing group it assimilated injection mouldings and designed and manufactured printed circuit boards. On 2 March 1990 Hosiden Corporation, acquired the company. Its capabilities now include acoustic, electronic, research and development, fire products, transmission products, manufacture and assembly, injection molding, and distribution.", "Engineering,_Manufacturing": 0.9971923828, "qwen": "Yes"}
{"id": "2958034", "revid": "1051085469", "url": "https://en.wikipedia.org/wiki?curid=2958034", "title": "Supply network operations", "text": "Supply network operations are the synchronized execution of compliant manufacturing and logistics processes across a dynamically reconfigurable supply network to profitably meet demand.supply network", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "40608530", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=40608530", "title": "Motiograph", "text": "Motiograph (originally The Enterprise Optical Manufacturing Company) was a film equipment company established by Alvah C Roebuck in Chicago in 1896. The company manufactured theater projectors and speakers. Their Optiograph 35 mm film projector was first introduced in 1898 and sold via catalogs including Sears. This was a smaller projector suitable for homes and schools. Beginning in 1908, all products released by the Enterprise Optical Manufacturing Company carry the brand name Motiograph. In 1911, their first theater grade 35 mm projector (Motiograph model D) was released. Roebuck sold the company in 1924 to a group of investors led by O.F. Spahr and Fred Matthews who would become the new President and Secretary, respectively. The Matthews family would retain ownership from then on. In 1936, they change the company name from the Enterprise Optical Manufacturing Company to become Motiograph, Inc. Also in 1936, Motiograph releases the very popular model K projector and continues to innovate after the war years. The date of the company's closure is unverified, but by 1969 it had failed to renew any copyrights for its products. The last corporate listing for Motiograph in Illinois is from 1973.", "Engineering,_Manufacturing": 0.9990692735, "qwen": "Yes"}
{"id": "38815844", "revid": "45767163", "url": "https://en.wikipedia.org/wiki?curid=38815844", "title": "List of GSK plc products", "text": "This is a list of products manufactured by the multinational pharmaceutical, biologics, and vaccines manufacturing company GSK.", "Engineering,_Manufacturing": 0.9999889135, "qwen": "Yes"}
{"id": "38820696", "revid": "44473045", "url": "https://en.wikipedia.org/wiki?curid=38820696", "title": "A&G Management Consulting", "text": "A&G is a management consulting Italian company based in Turin. It nationally and internationally operates in the fields of Manufacturing and Services, Finance, Banking and Insurance.\nThrough the group's company A&G acts in new economy and e-business. Through its partnership with the Russian start-up Intelligent Ideas A&G expands its range of activities in the Russian and international markets.\nA&G also works in the field of Culture, financing Italian and foreign film works.", "Engineering,_Manufacturing": 0.8504372835, "qwen": "Yes"}
{"id": "59537838", "revid": "68043", "url": "https://en.wikipedia.org/wiki?curid=59537838", "title": "Chip on board", "text": "Chip on board (COB) is a method of circuit board manufacturing in which the integrated circuits (e.g. microprocessors) are attached (wired, bonded directly) to a printed circuit board, and covered by a blob of epoxy. By eliminating the packaging of individual semiconductor devices, the completed product can be more compact, lighter, and less costly. In some cases, COB construction improves the operation of radio frequency systems by reducing the inductance and capacitance of integrated circuit leads. \nCOB effectively merges two levels of electronic packaging: level 1 (components) and level 2 (wiring boards), and may be referred to as \"level 1.5\".\nConstruction.\nA finished semiconductor wafer is cut into dies. Each die is then physically bonded to the PCB. \nThree different methods are used to connect the terminal pads of the integrated circuit (or other semiconductor device) with the conductive traces of the printed circuit board. \nFlip chip.\nIn \"flip chip on board\", the device is inverted, with the top layer of metallization facing the circuit board. Small balls of solder are placed on the circuit board traces where connections to the chip are required. The chip and board are passed through a reflow soldering process to make the electrical connections. \nWire bonding.\nIn \"wire bonding\", the chip is attached to the board with an adhesive. Each pad on the device is connected with a fine wire lead that is welded to the pad and to the circuit board. This is similar to the way that an integrated circuit is connected to its lead frame, but instead the chip is wire-bonded directly to the circuit board. \nFlexible circuit board.\nIn \"tape-automated bonding\", thin flat metal tape leads are attached to the semiconductor device pads, then welded to the printed circuit board. \nIn all cases, the chip and connections are covered with an encapsulant to reduce entry of moisture or corrosive gases to the chip, to protect the wire bonds or tape leads from physical damage, and to help dissipate heat.\nThe printed circuit board substrate may be assembled into the final product, for example, as in a pocket calculator, or, in the case of a multi-chip module, the module may be inserted in a socket or otherwise attached to yet another circuit board. The substrate wiring board may include heat-dissipating layers where the mounted devices handle significant power, such as in LED lighting or power semiconductors. Or, the substrate may have low-loss properties required at microwave radio frequencies.\nCOB LED modules.\nCOBs containing arrays of light-emitting diodes have made LED lighting more efficient.\n LED COBs include a layer of silicone containing yellow Ce:YAG phosphor that encapsulates the LEDs and turns the blue light of the LEDs into white light. The COB is usually built on an aluminum PCB that provides good thermal conductivity to a heatsink. COB LEDs could be compared with multi chip modules or hybrid integrated circuits since all three can incorporate multiple dies into a single unit. \nCOB variants are also used in newer LED bulbs as in this case the substrate can be either glass, sapphire or sometimes regular phenolic.\nWith a transparent substrate the LED chips may be installed \"upside down\" shining through for higher outcoupling. Typically they are glued to the substrate with UV setting glue, interconnects attached, and the encapsulant and phosphor applied in a single step with a back reflective coating applied to channel light out of the device.", "Engineering,_Manufacturing": 0.999843955, "qwen": "Yes"}
{"id": "59552075", "revid": "35498457", "url": "https://en.wikipedia.org/wiki?curid=59552075", "title": "Asahi India Glass", "text": "Asahi India Glass Limited, known as AIS, is a glass solutions and manufacturing company in India. It was established in 1984. It manufactures automotive safety glass, float glass, architectural processed glass, and glass products. It also provides consumer glass offerings in the form of Glasxperts and Windshield Experts. AIS was established as a Joint Venture agreement between Mr. BM Labroo and family, Asahi Glass Co. Ltd. (AGC Inc.), Japan, and Maruti Suzuki India Ltd. In the Indian passenger car glass segment, AIS has 77.1% market share as of 2017. AIS also holds 20% market share in India’s architectural glass segment as of 2017.\nHistory.\n1984-2000.\nIn 1984, AIS was initially incorporated in India under the name Indian Auto Safety Glass Private Limited. By 1986, the company transferred its equity stake to Asahi Glass Co., Japan. During this period, a joint venture agreement was carried out among the promoters, namely Asahi Glass Co., Japan, Indo-Asahi Glass Company and Maruti Udyog.\nThe company was thus incorporated as public limited company under the name of Asahi India Safety Glass Limited on 31 December 1985. Initially, the company only manufactured toughened glass for Maruti Suzuki India Limited. However, in 1989, after increasing its tempered glass production capacity by installing a new furnace, the company began manufacturing toughened glass for other automobile manufacturers. The company also introduced black ceramic printing and heat-lite printing for production of automotive glasses for the first time in India.\nBy 1992, the company ventured into manufacturing of laminated safety windshields. Four years later, anticipating an increase in demand of laminated windshields due to them being made mandatory for passenger vehicles under revised Central Motor Vehicle Rules, AIS carried out a major capacity expansion to produce 7,50,000 laminated windshields.\nBy 1999, the company added Hyundai, Ford, Toyota, and Hindustan Motors to its clientele while also increasing its tempered glass production capacity.\n2000-present.\nWith the turn of the millennium, AIS increased its technology capabilities with a slew of installations including laminated bending furnace for producing complex laminated windshields, CAD station and in-house designing, and print marking on glass for brand visibility.\nIn 2001, Float Glass India, a subsidiary of Asahi Glass Co., Japan, became the subsidiary of AIS. Next year, AIS made its first acquisition by acquiring 79.6% stake in Float Glass India and absorbing it under its own brand name.\nIn 2002, the company also rebranded itself as Asahi India Glass Limited (AIS) and in 2003, it set up a new automotive glass manufacturing plant in Chennai. This was followed by commencement of commercial production at the company’s Architectural Processing Unit in Taloja in 2004. In 2005, AIS Glass Solutions Ltd. was set up to further expand in the architectural glass value chain.\nThe year 2006 saw establishment of two more architectural processing facilities in Rewari and Chennai along with further capacity expansion across existing plants. In late 2017, AIS inaugurated a new, modernised Taloja float glass plant to enhance supply to auto and architectural glass segments by manufacturing 550 tonnes of glass per day.\nCompany structure and operations.\nOffices.\nAsahi India Glass Ltd’s registered office is situated in New Delhi. Their corporate office is located in Gurgaon, Haryana. \nThey have zonal offices in Delhi, Mumbai, Kolkata and Chennai and one regional office in Pune.\nManufacturing plants.\nAIS has 13 manufacturing plants and sub-assembly units across India. In May 2017, AIS announced its plan to invest in a Greenfield Automotive Glass Plant near Mehsana, Gujarat, in order to primarily supply the new Maruti Suzuki India Limited plant in Gujarat. In November 2017, AIS commenced float glass manufacturing at its new Taloja plant at MIDC Industrial Area, Raigad District, Maharashtra.\nStrategic business units.\nAIS has three strategic business units. These are Automotive Glass, Architectural Glass and Consumer Glass.\nAutomotive glass.\nAIS Auto Glass is the automotive glass SBU of AIS. It provides glass to automobile manufacturers including Maruti Udyog, Tata Motors, Hyundai Motors, Mahindra & Mahindra, General Motors Ford India, Fiat India, Honda, Eicher, Volvo, Hindustan Motors, Skoda Auto, Volkswagen India, Toyota Kirloskar, and Piaggio. \nAIS Auto Glass has four production facilities at Bawal (Haryana), Roorkee (Uttarakhand), Chennai (Tamil Nadu), and Taloja (Maharashtra). They also have five automotive glass manufacturing plants in India.\nAcquisitions and sales.\nIn 2001, AIS acquired a stake in Asahi Glass Co., Japan’s subsidiary Float Glass India. In 2003, the amalgamation of the two companies was approved with 79.6% equity in FGI held by AIS.\nIn 2017, AIS and four other investors concluded a deal to acquire Timex Group Precision Engineering Limited which is the Indian subsidiary of Timex Nederland BV. This acquisition was carried out via a joint venture firm Scopfy Components Pvt Ltd.\nAwards.\nIn 2007, AIS was rated as the ‘Best Indian Company in Glass and Ceramics’ by Dun & Bradstreet. \nIn the same year, the Union of Japanese Scientists and Engineers (JUSE) awarded AIS Auto Glass with the Deming Application Prize 2007.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "59553153", "revid": "44271930", "url": "https://en.wikipedia.org/wiki?curid=59553153", "title": "Universal Instruments Corporation", "text": "Universal Instruments Corporation is an electronics technology company based in Conklin, New York. Universal Instruments builds automated machines that allow electronics manufacturing services companies to construct surface-mount technology and through-hole technology circuits, such as SMT placement equipment, insertion mount machines, and machines for electronic packaging. The company was founded in 1919 as the Universal Instruments and Metal Company in nearby Vestal, and found its initial success as a tool and die maker for IBM. In addition to electronics manufacturing machine, Universal Instruments manufactures DEKA's Luke Arm prosthetic for Mobius Bionics.", "Engineering,_Manufacturing": 1.0000082254, "qwen": "Yes"}
{"id": "31654848", "revid": "548440", "url": "https://en.wikipedia.org/wiki?curid=31654848", "title": "Pridgeon & Clay", "text": "Pridgeon & Clay provides metal stamping and fine-blank components, specializing in exhaust components for the automotive industry. Pridgeon & Clay also produces components for the class 8 truck, agriculture, medical, battery, fuel cell and other alternative energy industries. The company holds ISO 14001 and TS 16949 certifications, which allow the company to carry out its own product validation.\nPridgeon & Clay's Advanced Engineering Lab is an A2LA accreditation, independent testing facility. The Advanced Engineering Lab has developed new products and techniques, including patented selective catalytic reduction (SCR) mixing modules, reverse-extrusion catalytic converter cones, fuel cells and battery components for zero-emissions vehicles.\nHistory.\nJohn Pridgeon & Donald V. Clay founded the privately held company in 1948. In 1976, John Pridgeon retired from the company, leaving sole ownership to his partner Don Clay. In 1992, Don sold the business to his sons, Donald C. Clay and Robert E. Clay. Donald C. Clay retired in 2008, and Robert E. Clay remains as CEO of Pridgeon & Clay.\nGlobal Production.\nPridgeon & Clay operates in four manufacturing facilities worldwide, with Sales & Engineering offices in North America, Europe & China. The company has over 95 stamping presses worldwide ranging from 40 to 1500 tons, plus other manufacturing equipment to execute a variety of production services:\nUnited States.\nPridgeon & Clay operates two locations in the United States, in Michigan and Indiana. The Grand Rapids, Michigan location houses the head office, a manufacturing plant, a distribution center, and a Research & Development and Advanced Engineering facility. As the main production facility, Grand Rapids runs over 70 presses ranging from 40 tons to 1500 tons with customized steel feed systems that accommodate rolled coils or flat blanks. The manufacturing plant in Franklin, Indiana specializes in lighter gauge stamping up to 400 tons, plus MIG and resistance welding, tube cut-off, sizing, and forming.\nHungary.\nAcquired by Pridgeon & Clay in 2001, the Apostag facility has over of manufacturing space. Located less than 80 kilometers south of Budapest, Pridgeon & Clay, KFT manufactures metal stampings and tooling for the automotive industry with progressive and transfer presses up to 800 tons. The facility is TS-16949 Certified.\nMexico.\nPridgeon & Clay's Mexico facility is located in Monterrey, Mexico, just 15 km from Monterrey International Airport, and just 200 km from the USA Texas border. P &C Mex offers progressive metal stamping on multiple presses up to 1,000 tons. Press bed sizes are as large as 4.6 meters (180 inches). The facility is TS-16949 Certified.\nGermany and China.\nPridgeon & Clay also opened sales and engineering offices in Germany and Shanghai, China in 2007.\nReferences.\nAll photos and logos used in this article have been used with permission from Pridgeon & Clay.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "73176605", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=73176605", "title": "2022–23 Iranian Basketball Super League", "text": "The 2022–23 Iran Super League season was the 33rd season of the Iranian basketball league. Shahrdari Gorgan won the title after beating Kalleh Mazandaran in the final.\nPlayoffs.\nRelegation.\nThe higher-seeded team played the first, second and fifth leg (if necessary) at home.\nQuarterfinals.\nThe higher-seeded team played the first, second and fifth leg (if necessary) at home.\nSemifinals.\nThe higher-seeded team played the first and third leg (if necessary) at home. \nFinal.\nThe higher-seeded team played the first and third leg (if necessary) at home. ", "Engineering,_Manufacturing": 0.9990997314, "qwen": "Yes"}
{"id": "48491973", "revid": "42425010", "url": "https://en.wikipedia.org/wiki?curid=48491973", "title": "Federal Motor Vehicle Safety Standard 208", "text": "Federal Motor Vehicle Safety Standard 208 (FMVSS 208) regulates automotive occupant crash protection in the United States. Like all other Federal Motor Vehicle Safety Standards, FMVSS 208 is administered by the United States Department of Transportation's National Highway Traffic Safety Administration.\nThis standard originally specified the type of occupant restraints (i.e., seat belts) required. It was amended to specify performance requirements for anthropomorphic test dummies seated in the front outboard seats of passenger cars and of certain multi-purpose passenger vehicles, trucks, and buses, including the active and passive restraint systems. The purpose of the standard is to reduce the number of fatalities and the number and severity of injuries to occupants involved in frontal crashes.", "Engineering,_Manufacturing": 0.9999351501, "qwen": "Yes"}
{"id": "31725473", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=31725473", "title": "Pam-Crash", "text": "Pam-Crash is a software package from ESI Group used for crash simulation and the design of occupant safety systems, primarily in the automotive industry. The software enables automotive engineers to simulate the performance of a proposed vehicle design and evaluate the potential for injury to occupants in multiple crash scenarios.\nHistory.\nThe software originated in research aimed at simulating aerospace and nuclear applications. At a meeting organized by VDI (Verein Deutscher Ingenieure) in Stuttgart on May 30, 1978, ESI Group simulated the accidental crash of a military fighter plane into a nuclear power plant German automobile manufacturers took note and tested the applicability of several emerging commercial crash simulation codes, including what would soon become Pam-Crash. This software's predecessor code simulated the frontal impact of a full passenger car structure in an overnight computer run. This was the first successful full-car crash simulation. \nBased on Finite element method (FEM), the software enables the modeling of complex geometry by offering different structural and continuum elements: beams, shells, membranes and solids. In a typical crash simulation, shells are used to model thin-walled metal, plastic and composite components. Beams and bars may also be used for stiffening frames, suspensions and special connections. The program offers a large range of linear and nonlinear materials including elastic and visco-plastic and including foam materials and multi-layers composites up to damage and failure models. It was used in the first numerical simulation of a full vehicle rollover by BMW AG (Bayerische Motoren Werke AG). The program provided accurate determination of the structural deformations while the computationally economical rigid body simulation was used during the relatively unimportant deformation and free-flight phases of the simulation. \nPAM-CRASH is used on High Performance Computers including massively parallel systems. One of the most time-critical aspects of parallel simulation is the contact handling. Results with a 128-processor computer demonstrated that a contact search algorithm leads to a better scalability. Engineers utilize crash simulation not only to determine the end result of the crash but also to view the step by step time history. Observing factors such as how the bumper is folded in the impact and what is the effect of rib thickness on body deformation in the initial stages of the simulation gives insights that improve crashworthiness of the design. \n\"Desktop Engineering\" magazine, in its review of ESI Group’s Virtual Performance Solution, which includes this software, said: “You work across multiple analysis domains with a single core model—not different models for every load case. This streamlines your workflow, saving time and money by reducing the number of individual solvers you have to deploy and all that model re-creation business.”\nApplications.\nPam-Crash was used to design a steel floor pan structure to meet torsion and bending stiffness requirements while reducing its weight by 50% and the number of parts by 70%.\nIn a different application, the software was dynamically coupled to the occupant safety program MADYMO. The study investigated the interaction of a Hybrid III crash dummy and a passive restraint system of an airbag and kneebolster in a frontal impact situation. Good agreement with experimental data was obtained. \nResearchers at the University of North Carolina and Mississippi State University simulated crash scenarios on a Chrysler Neon passenger vehicle using this program and LS-DYNA, another crash simulation code. The test data and simulation results correlated very well with only minor discrepancies in terms of overall impact deformation, component failure modes and velocity and acceleration at various locations on the vehicle.\nThe software was used to evaluate safety issues at the Beryl Bravo offshore platform in the North Sea operated by ExxonMobil. It was used to perform numerical simulations of the dynamic response of the structure subjected to explosion scenarios. The program's computational models agreed with experimental results and were used to guide the process of designing new blast walls. \nThe program is used by automobile manufacturers to improve their rankings in New Car Assessment Programs (NCAPs) used to assess the safety performance of competing automobile models. These programs include the Euro NCAP and Japan NCAP as well as a similar rating system provided by the National Highway Traffic Safety Administration (NHTSA).", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "1754048", "revid": "44120587", "url": "https://en.wikipedia.org/wiki?curid=1754048", "title": "Agile manufacturing", "text": "Agile manufacturing is a term applied to an organization that has created the processes, tools, and training to enable it to respond quickly to customer needs and market changes while still controlling costs and quality. It is mostly related to lean manufacturing.\nAn enabling factor in becoming an agile manufacturer has been the development of manufacturing support technology that allows the marketers, the designers and the production personnel to share a common database of parts and products, to share data on production capacities and problems—particularly where small initial problems may have larger \"downstream\" effects. It is a general proposition of manufacturing that the cost of correcting quality issues increases as the problem moves downstream, so that it is cheaper to correct quality problems at the earliest possible point in the process.\nAgile manufacturing is seen as the next step after lean manufacturing in the evolution of production methodology. The key difference between the two is like between a thin and an athletic person, agile being the latter. One can be neither, one or both. In manufacturing theory, being both is often referred to as leagile.\nAccording to Martin Christopher, when companies have to decide what to be, they have to look at the customer order cycle (COC) (the time the customers are willing to wait) and the leadtime for getting supplies. If the supplier has a short lead time, lean production is possible. If the COC is short, agile production is beneficial.\nAgile manufacturing is an approach to manufacturing which is focused on meeting the needs of customers while maintaining high standards of quality and controlling the overall costs involved in the production of a particular product. This approach is geared towards companies working in a highly competitive environment, where small variations in performance and product delivery can make a huge difference in the long term to a company's survival and reputation among consumers.\nThis concept is closely related to lean manufacturing, in which the goal is to reduce waste as much as possible. In lean manufacturing, the company aims to cut all costs which are not directly related to the production of a product for the consumer. Agile manufacturing can include this concept, but it also adds an additional dimension, the idea that customer demands need to be met rapidly and effectively. In situations where companies integrate both approaches, they are sometimes said to be using \"agile and lean manufacturing\".\nCompanies which utilize an agile manufacturing approach tend to have very strong networks with suppliers and related companies, along with numerous cooperative teams which work within the company to deliver products effectively. They can retool facilities quickly, negotiate new agreements with suppliers and other partners in response to changing market forces, and take other steps to meet customer demands. This means that the company can increase production on products with a high consumer demand, as well as redesign products to respond to issues which have emerged on the open market.\nMarkets can change very quickly, especially in the global economy. A company which cannot adapt quickly to change may find itself left behind, and once a company starts to lose market share, it can fall rapidly. The goal of agile manufacturing is to keep a company ahead of the competition so that consumers think of that company first, which allows it to continue innovating and introducing new products, because it is financially stable and it has a strong customer support base.\nCompanies that want to switch to the use of agile manufacturing can take advantage of consultants who specialize in helping companies convert and improve existing systems. Consultants can offer advice and assistance which is tailored to the industry a company is involved in, and they usually focus on making companies competitive as quickly as possible with proved agile techniques. There are also a number of textbooks and manuals available with additional information on agile manufacturing techniques and approaches.\nAnother approach was developed combining the attributes of agility together with leanness across one supply chain is the hybrid lean-agile strategy. This blended lean-agile strategy hybridizes attributes of leanness (cost minimization, waste reduction, continuous improvement), agility (speed, flexibility, responsiveness) and leagility (mass customization, postponement) in one supply network. The significance of the hybridized lean aspect is higher upstream the supply chain than the agility dimension in the same supplier node, compared to downstream the supply chain at the distributor node closer to the customers, which operates in a more agile manner.", "Engineering,_Manufacturing": 0.9999829531, "qwen": "Yes"}
{"id": "1757560", "revid": "38289875", "url": "https://en.wikipedia.org/wiki?curid=1757560", "title": "Currency detector", "text": "A currency detector or currency validator is a device that determines whether notes or coins are genuine or counterfeit. These devices are used in a wide range of automated machines, such as retail kiosks, supermarket self checkout machines, arcade gaming machines, payphones, launderette washing machines, car park ticket machines, automatic fare collection machines, public transport ticket machines, and vending machines.\nThe process involves examining the coins and/or notes that have been inserted into the machine, and conducts various tests to determine if the currency is counterfeit. Because the parameters are different for each coin or note, these currency acceptors must be correctly programmed for each item to be accepted.\nIn normal operation, if any item such as a coin, banknote, card or ticket is accepted, it is retained within the machine and it falls into a storage container to allow a member of staff to collect it later when emptying the machine. If the item is rejected, the machine returns the item to the customer. If a coin is rejected, it usually falls into a tray or rolls out of a slot at the bottom where the customer can remove the coin. If a banknote, card or ticket is rejected, it is ejected out of the machine so that the customer can remove it from the slot into which it was inserted.\nCoin acceptors.\nThe basic principle for coin detection is to test the physical properties of the coin against known characteristics of acceptable coins. The coin acceptor identifies the coin according to its mass, size, diameter, thickness, metal composition and/or magnetism, and then sends an appropriate electrical signal via its output connection. The next step is generally performed by the banknote-to-coins exchanger.\nToday, sophisticated electronic coin acceptors are being used in some places that, in addition to examining the mass, weight and size, also scan the inserted coin using optical laser beams and match the image to a pre-defined list, or test the coin's \"metallic signature\" based on its metallic composition.\nNormal circulation coins eventually collect microscopic particles of dirt, dust, oil and grease from people's fingers. When a coin acceptor is used for a long time, thousands of coins rolling along a track will leave enough dirt, dust, oil and grease to be visible. As a consequence of this, the coin acceptor must be cleaned properly on a regular basis to prevent malfunction or damage. Coin acceptors are modular, so a dirty acceptor can be replaced with a clean unit, minimising downtime. The old unit is then cleaned and refurbished.\nSome new types of coin acceptors are able to recognize the coins through \"training\", so they will support any new types of coins or tokens when correctly introduced.\nTesting methods.\nVending and change machines use several methods of deciding whether a banknote is genuine. Adjusting these settings and the sensitivity of each is programmed via means of DIP switches on the internal circuitry.\nOptical sensing.\nOptical sensing with a small light detector called a photocell or a miniature digital camera is one of the main techniques that vending machines use. Many countries' banknotes are pixelated—that is, they are made out of small dots. The dots are spaced differently and have different sizes, depending on the note. The optical sensors can look for these different patterns to determine what sort of note has been inserted. Some paper money is also fluorescent: it glows when ultraviolet light is shined on it. Some machines shine an ultraviolet light on the note and measure the glow to help determine the banknote's material composition.\nGMR sensor proximity detection.\nThe particles in the ink on many countries' currency have ferromagnetic properties, including some elemental iron. Magnetic composition comprises carbon nanofoam in an amount of from 0.1 to 45 percent by weight of the total composition.\nNotes are passed over a permanent magnet array and magnetized along their direction of travel. A magnetic sensor located several inches away with its sensitive axis parallel to the direction of travel can detect the remnant field of the ink particles.\nThe purpose of the biasing magnet in this case is to achieve a controlled orientation of the magnetic moments of the ink particles, resulting in a maximum and recognizable magnetic signature. Reversing the magnetizing field can actually invert the signature.\nPhysical attributes.\nThe thickness and dimensions of a banknote are tested to ensure they are correct. US currency is 2.61 inches wide by 6.14 inches in length and are 0.0042 inches thick, and weigh 1 gram. Currency printed prior to 10 July 1929 had larger physical characteristics. As the notes pass between the rollers, the voltages vary according to their thickness.\nMiniature transducers, approximately 3/8\" diameter, offer high accuracy linear measurement in a compact space where size constraints prohibit the use of standard LVDTI's. In addition, the low- mass core is ideal for systems with low driving forces or high acceleration and, therefore, will not adversely influence the delicate nature of these applications. Operating ranges are available from ±0.005\" to ±1.00\", divided into eight intermediate strokes.\nGenuine Federal Reserve notes have a clear polyester thread embedded vertically in the paper. The thread is inscribed with the denomination of the note, and is visible only when held up to light. Each denomination has a unique thread position and will glow a unique color in ultraviolet (UV) light.\nBanknote acceptors.\nAlso known as validators or acceptors, paper currency detectors scan paper currency using optical and magnetic sensors. Upon validation, the validator will inform the vending machine controller (VMC) or other host device of a credit via a parallel or serial interface. Various interfaces exist for the host device, including a single-line pulse interface, a multi-line parallel interface, a multi-line binary interface, and serial interfaces such as ccTalk, SSP, and MDB. Wrinkled or creased notes can cause these machines to reject them.\nThere are currently only a handful of companies manufacturing this equipment. Crane Payment Innovations (joining Crane Payment Solutions and MEI), and Japan Cash Machine (JCM) are two of the largest, each maintaining dominance in a particular market segment. Other notable companies producing this type of equipment include Coinco, Pyramid Technologies, Inc. (PTI), International Currency Technologies (ICT), Alpha CMS (Cash Management Solutions), Astrosys, Pyramid Technologies, Validation Technologies International (VTI), Innovative Technology Ltd (ITL), Global Payment Technologies (GPT) and Jofemar.\nRecent innovations include remote auditing and reporting by these devices as part of an Automated Cash Handling network for entertainment, banking, retail, casino and other industries.", "Engineering,_Manufacturing": 0.9948192835, "qwen": "Yes"}
{"id": "1758144", "revid": "1535071", "url": "https://en.wikipedia.org/wiki?curid=1758144", "title": "Laser trimming", "text": "Laser trimming is the manufacturing process of using a laser to adjust the operating parameters of an electronic circuit.\nOne of the most common applications uses a laser to burn away small portions of resistors, raising their resistance value. The burning operation can be conducted while the circuit is being tested by automatic test equipment, leading to optimum final values for the resistor(s) in the circuit.\nThe resistance value of a film resistor is defined by its geometric dimensions (length, width, height) and the resistor material. A lateral cut in the resistor material by the laser narrows or lengthens the current flow path and increases the resistance value. The same effect is obtained whether the laser changes a thick-film or a thin-film resistor on a ceramic substrate or an SMD-resistor on a SMD circuit. The SMD-resistor is produced with the same technology and may be laser trimmed as well.\nTrimmable chip capacitors are built up as multilayer plate capacitors. Vaporizing the top layer with a laser decreases the capacitance by reducing the area of the top electrode.\nPassive trim is the adjustment of a resistor to a given value. If the trimming adjusts the whole circuit output such as output voltage, frequency, or switching threshold, this is called active trim. During the trim process, the corresponding parameter is measured continuously and compared to the programmed nominal value. The laser stops automatically when the value reaches the nominal value.\nTrimming LTCC resistances in a pressure chamber.\nOne type of passive trimmer uses a pressure chamber to enable resistor trimming in a single run. The LTCC boards are contacted by test probes on the assembly side and trimmed with a laser beam from the resistor side. This trimming method requires no contact points between the resistances, because the fine pitch adapter contacts the component on the opposite side of where the trimming occurs. Therefore, the LTCC can be arranged more compactly and less expensively.\nFunction mode:\nAdvantages of this method: \nTrimming potentiometers.\nOften designers use potentiometers, which are adjusted during end testing until the desired function of the circuit is reached. In many applications, the end user of the product would prefer not to have potentiometers, as they can drift, be mis-adjusted or develop noise. Therefore, manufacturers determine the needed resistance or capacitance values by measurement and calculation methods and afterwards solder the suitable component into the final PCB; this approach is called \"Select on Test\" (SOT) and is quite labor-intensive.\nIt is simpler to substitute the potentiometer or the SOT part with a trimmable chip resistor or chip capacitor, and the potentiometer adjusting screwdriver is replaced by the laser trimming. The achieved accuracy can be higher, the procedure can be automated, and the long-term stability is better than with potentiometers and at least as good as with SOT components. Often the laser for active trimming can be integrated in existing measurement systems by the manufacturer.\nProgram from digital logic circuits.\nA similar approach can be used to program digital logic circuits. In this case, fuses are blown by the laser, enabling or disabling various logic circuits. An example of this is the IBM POWER4 microprocessor where the chip contains five banks of cache memory but only requires four banks for full operation. During testing, each cache bank is exercised. If a defect is found in one bank, that bank can be disabled by blowing its programming fuse. This built-in redundancy allows higher chip yields than would be possible if all cache banks had to be perfect in every chip. If no bank is defective, a fuse can be blown arbitrarily, leaving just four banks.", "Engineering,_Manufacturing": 0.9999555349, "qwen": "Yes"}
{"id": "1758939", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1758939", "title": "Computer-integrated manufacturing", "text": "Computer-integrated manufacturing (CIM) is the manufacturing approach of using computers to control the entire production process. This integration allows individual processes to exchange information with each part. Manufacturing can be faster and less error-prone by the integration of computers. Typically CIM relies on closed-loop control processes based on real-time input from sensors. It is also known as flexible design and manufacturing.\nOverview.\nCIM is an example of the implementation of information and communication technologies (ICTs) in manufacturing.\nCIM implies that there are at least two computers exchanging information, e.g. the controller of an arm robot and a micro-controller.\nCIM is most useful where a high level of ICT is used in the company or facility, such as CAD/CAM systems, and the availability of process planning and its data.\nHistory.\nThe idea of \"digital manufacturing\" became prominent in the early 1970s, with the release of Dr. Joseph Harrington's book, Computer Integrated Manufacturing. However, it was not until 1984 when computer-integrated manufacturing began to be developed and promoted by machine tool manufacturers and the Computer and Automated Systems Association and Society of Manufacturing Engineers (CASA/SME).\nTopics.\nKey challenges.\nThere are three major challenges to development of a smoothly operating computer-integrated manufacturing system:\nSubsystems.\nA computer-integrated manufacturing system is not the same as a \"\"lights-out factory\"\", which would run completely independent of human intervention, although it is a big step in that direction. Part of the system involves flexible manufacturing, where the factory can be quickly modified to produce different products, or where the volume of products can be changed quickly with the aid of computers. Some or all of the following subsystems may be found in a CIM operation:\nComputer-aided techniques:\nDevices and equipment required:\nTechnologies:\nOthers:\nCIMOSA.\nCIMOSA (Computer Integrated Manufacturing Open System Architecture), is a 1990s European proposal for an open systems architecture for CIM developed by the AMICE Consortium as a series of ESPRIT projects. The goal of CIMOSA was \"to help companies to manage change and integrate their facilities and operations to face world wide competition. It provides a consistent architectural framework for both enterprise modeling and enterprise integration as required in CIM environments\".\nCIMOSA provides a solution for business integration with four types of products:\nCIMOSA according to Vernadat (1996), coined the term business process and introduced the process-based approach for integrated enterprise modeling based on a cross-boundaries approach, which opposed to traditional function or activity-based approaches. With CIMOSA also the concept of an \"Open System Architecture\" (OSA) for CIM was introduced, which was designed to be vendor-independent, and constructed with standardised CIM modules. Here to the OSA is \"described in terms of their function, information, resource, and organizational aspects. This should be designed with structured engineering methods and made operational in a modular and evolutionary architecture for operational use\".\nAreas.\nThere are multiple areas of usage:", "Engineering,_Manufacturing": 1.0000064373, "qwen": "Yes"}
{"id": "495768", "revid": "46051363", "url": "https://en.wikipedia.org/wiki?curid=495768", "title": "Powder metallurgy", "text": "Powder metallurgy (PM) is a term covering a wide range of ways in which materials or components are made from metal powders. PM processes can reduce or eliminate the need for subtractive processes in manufacturing, lowering material losses and reducing the cost of the final product.\nPowder metallurgy is also used to make unique materials impossible to get from melting or forming in other ways. A very important product of this type is tungsten carbide. Tungsten carbide is used to cut and form other metals and is made from tungsten carbide particles bonded with cobalt. It is very widely used in industry for tools of many types and globally ~50,000 tonnes per year is made with powder metallurgy. Other products include sintered filters, porous oil-impregnated bearings, electrical contacts and diamond tools.\nSince the advent of industrial production-scale metal powder-based additive manufacturing in the 2010s, selective laser sintering and other metal additive manufacturing processes are a new category of commercially important powder metallurgy applications.\nOverview.\nThe powder metallurgy \"press and sinter\" process generally consists of three basic steps: powder blending (or pulverisation), die compaction, and sintering. Compaction of the powder in the die is generally performed at room temperature. Sintering is the process of binding a material together with heat without liquefying it. It is usually conducted at atmospheric pressure, and under carefully controlled atmosphere composition. To obtain special properties or enhanced precision, secondary processing like coining or heat treatment often follows.\nOne of the older such methods is the process of blending fine (carbon, copper, and/or nickel. This produces precise parts, normally very close to the die dimensions, but with 5–15% porosity, and thus sub-wrought steel properties. This method is still used to make around 1 Mt/y of structural components of iron-based alloys. \nThere are several other PM processes which have been developed over the last fifty years. These include:\nHistory and capabilities.\nThe history of powder metallurgy and the art of metal and ceramic sintering are intimately related to each other. Sintering involves the production of a hard solid metal or ceramic piece from a starting powder. The ancient Incas made jewelry and other artifacts from precious metal powders, though mass manufacturing of PM products did not begin until the mid or late 19th century. In these early manufacturing operations, iron was extracted by hand from metal sponge following reduction and was then reintroduced as a powder for final melting or sintering.\nA much wider range of products can be obtained from powder processes than from direct alloying of fused materials. In melting operations the \"phase rule\" applies to all pure and combined elements and strictly dictates the distribution of liquid and solid phases which can exist for specific compositions. In addition, whole body melting of starting materials is required for alloying, thus imposing unwelcome chemical, thermal, and containment constraints on manufacturing. Unfortunately, the handling of aluminium/iron powders poses major problems. Other substances that are especially reactive with atmospheric oxygen, such as titanium, are sinterable in special atmospheres or with temporary coatings.\nIn powder metallurgy or ceramics it is possible to fabricate components which otherwise would decompose or disintegrate. All considerations of solid-liquid phase changes can be ignored, so powder processes are more flexible than casting, extrusion, or forging techniques. Controllable characteristics of products prepared using various powder technologies include mechanical, magnetic, and other unconventional properties of such materials as porous solids, aggregates, and intermetallic compounds. Competitive characteristics of manufacturing processing (e.g. tool wear, complexity, or vendor options) also may be closely controlled.\nPowder production techniques.\nAny fusible material can be atomized. Several techniques have been developed which permit large production rates of powdered particles, often with considerable control over the size ranges of the final grain population. Powders may be prepared by crushing, grinding, chemical reactions, or electrolytic deposition. The most commonly used powders are copper-base and iron-base materials. \nPowders of the elements titanium, vanadium, thorium, niobium, tantalum, calcium, and uranium have been produced by high-temperature reduction of the corresponding nitrides and carbides. Iron, nickel, uranium, and beryllium submicrometre powders are obtained by reducing metallic oxalates and formates. Exceedingly fine particles also have been prepared by directing a stream of molten metal through a high-temperature plasma jet or flame, atomizing the material. Various chemical and flame associated powdering processes are adopted in part to prevent serious degradation of particle surfaces by atmospheric oxygen.\nIn tonnage terms, the production of iron powders for PM structural part production dwarfs the production of all of the non-ferrous metal powders combined. Virtually all iron powders are produced by one of two processes: the sponge iron process or water atomization.\nSponge iron process.\nThe longest established of these processes is the sponge iron process, the leading example of a family of processes involving solid state reduction of an oxide. In the process, selected magnetite (Fe3O4) ore is mixed with coke and lime and placed in a silicon carbide retort. The filled retort is then heated in a kiln, where the reduction process leaves an iron “cake” and a slag. In subsequent steps, the retort is emptied, the reduced iron sponge is separated from the slag and is crushed and annealed.\nThe resultant powder is highly irregular in particle shape, therefore ensuring good “green strength” so that die-pressed compacts can be readily handled prior to sintering, and each particle contains internal pores (hence the term “sponge”) so that the good green strength is available at low compacted density levels.\nSponge iron provides the\nfeedstock for all iron-based self-lubricating bearings, and still accounts for around 30% of iron powder usage in PM structural parts.\nAtomization.\nAtomization is accomplished by forcing a molten metal stream through an orifice at moderate pressures. A gas is introduced into the metal stream just before it leaves the nozzle, serving to create turbulence as the entrained gas expands (due to heating) and exits into a large collection volume exterior to the orifice. The collection volume is filled with gas to promote further turbulence of the molten metal jet. Air and powder streams are segregated using gravity or cyclonic separation. Most atomized powders are annealed, which helps reduce the oxide and carbon content. The water atomized particles are smaller, cleaner, and nonporous and have a greater breadth of size, which allows better compacting. The particles produced through this method are normally of spherical or pear shape. Usually, they also carry a layer of oxide over them.\nThere are three types of atomization:\nSimple atomization techniques are available in which liquid metal is forced through an orifice at a sufficiently high velocity to ensure turbulent flow. The usual performance index used is the Reynolds number:\nwhere is the fluid density, is the velocity of the exit stream, is the diameter of the opening, and is the absolute viscosity. At low Re the liquid jet oscillates, but at higher velocities the stream becomes turbulent and breaks into droplets. Pumping energy is applied to droplet formation with very low efficiency (on the order of ) and control over the size distribution of the metal particles produced is rather poor. Other techniques such as nozzle vibration, nozzle asymmetry, multiple impinging streams, or molten-metal injection into ambient gas are all available to increase atomization efficiency, produce finer grains, and to narrow the particle size distribution. Unfortunately, it is difficult to eject metals through orifices smaller than a few millimeters in diameter, which in practice limits the minimum size of powder grains to approximately . Atomization also produces a wide spectrum of particle sizes, necessitating downstream classification by screening and remelting a significant fraction of the grain boundary.\nCentrifugal disintegration.\nCentrifugal disintegration of molten particles offers one way around these problems. Extensive experience is available with iron, steel, and aluminium. Metal to be powdered is formed into a rod which is introduced into a chamber through a rapidly rotating spindle. Opposite the spindle tip is an electrode from which an arc is established which heats the metal rod. As the tip material fuses, the rapid rod rotation throws off tiny melt droplets which solidify before hitting the chamber walls. A circulating gas sweeps particles from the chamber. Similar techniques could be employed in space or on the Moon. The chamber wall could be rotated to force new powders into remote collection vessels, and the electrode could be replaced by a solar mirror focused at the end of the rod.\nAn alternative approach capable of producing a very narrow distribution of grain sizes but with low throughput consists of a rapidly spinning bowl heated to well above the melting point of the material to be powdered. Liquid metal, introduced onto the surface of the basin near the center at flow rates adjusted to permit a thin metal film to skim evenly up the walls and over the edge, breaks into droplets, each approximately the thickness of the film.\nOther techniques.\nAnother powder-production technique involves a thin jet of liquid metal intersected by high-speed streams of atomized water which break the jet into drops and cool the powder before it reaches the bottom of the bin. In subsequent operations the powder is dried. This is called water atomization. The advantage of water atomization is that metal solidifies faster than by gas atomization since the heat capacity of water is some magnitudes higher than gases. Since the solidification rate is inversely proportional to the particle size, smaller particles can be made using water atomization. The smaller the particles, the more homogeneous the micro structure will be. Notice that particles will have a more irregular shape and the particle size distribution will be wider. In addition, some surface contamination can occur by oxidation skin formation. Powder can be reduced by some kind of pre-consolidation treatment, such as annealing used for the manufacture of ceramic tools.\nPowder compaction.\nPowder compaction is the process of compacting metal powder in a die through the application of high pressures. Typically the tools are held in the vertical orientation with the punch tool forming the bottom of the cavity. The powder is then compacted into a shape and then ejected from the die cavity. In a number of these applications the parts may require very little additional work for their intended use; making for very cost efficient manufacturing.\nThe density of the compacted powder increases with the amount of pressure applied. Typical pressures range from 80 psi to 1000 psi (0.5 MPa to 7 MPa), pressures from 1000 psi to 1,000,000 psi have been obtained. Pressure of 10 t/in² to 50 t/in² (150 MPa to 700 MPa) are commonly used for metal powder compaction. To attain the same compression ratio across a component with more than one level or height, it is necessary to work with multiple lower punches. A cylindrical workpiece is made by single-level tooling. A more complex shape can be made by the common multiple-level tooling.\nProduction rates of 15 to 30 parts per minute are common.\nThere are four major classes of tool styles: single-action compaction, used for thin, flat components; opposed double-action with two punch motions, which accommodates thicker components; double-action with floating die; and double action withdrawal die. Double action classes give much better density distribution than single action. Tooling must be designed so that it will withstand the extreme pressure without deforming or bending. Tools must be made from materials that are polished and wear-resistant.\nBetter workpiece materials can be obtained by repressing and re-sintering.\nDie pressing.\nThe dominant technology for the forming of products from powder materials, in terms of both tonnage quantities and numbers of parts produced, is die pressing. There are mechanical, servo-electrical and hydraulic presses available in the market, whereby the biggest powder throughput is processed by hydraulic presses.\nThis forming technology involves a production cycle comprising:\nThis cycle offers a readily automated and high production rate process.\nDesign considerations.\nProbably the most basic consideration is being able to remove the part from the die after it is pressed, along with avoiding sharp corners in the design. Keeping the maximum surface area below and the height-to-diameter ratio below 7-to-1 is recommended. Along with having walls thicker than and keeping the adjacent wall thickness ratios below 2.5-to-1.\nOne of the major advantages of this process is its ability to produce complex geometries. Parts with undercuts and threads require a secondary machining operation. Typical part sizes range from to . in area and from in length. However, it is possible to produce parts that are less than and larger than . in area and from a fraction of an inch (2.54 cm) to approximately in length.\nIsostatic pressing.\nIn some pressing operations, such as hot isostatic pressing (HIP) compact formation and sintering occur simultaneously. This procedure, together with explosion-driven compressive techniques is used extensively in the production of high-temperature and high-strength parts such as turbine disks for jet engines. In most applications of powder metallurgy the compact is hot-pressed, heated to a temperature above which the materials cannot remain work-hardened. Hot pressing lowers the pressures required to reduce porosity and speeds welding and grain deformation processes. It also permits better dimensional control of the product, lessens sensitivity to physical characteristics of starting materials, and allows powder to be compressed to higher densities than with cold pressing, resulting in higher strength. Negative aspects of hot pressing include shorter die life, slower throughput because of powder heating, and the frequent necessity for protective atmospheres during forming and cooling stages.\nIsostatic powder compacting.\nIsostatic powder compacting is a mass-conserving shaping process. Fine metal particles are placed into a flexible mould and then high fluid pressure is applied to the mold, in contrast to the direct pressure applied by the die faces of a die pressing process. The resulting article is then sintered in a furnace which increases the strength of the part by bonding the metal particles. This manufacturing process produces very little scrap metal and can be used to make many different shapes. The tolerances that this process can achieve are very precise, ranging from +/- 0.008 inches (0.2 mm) for axial dimensions and +/- 0.020 inches (0.5 mm) for radial dimensions. This is the most efficient type of powder compacting (the following subcategories are also from this reference). This operation is generally only applicable on small production quantities, although the cost of a mold much lower than that of pressing dies it is generally not reusable and the production time is much longer.\nCompacting pressures range from to for most metals and approximately to for non-metals. The density of isostatic compacted parts is 5% to 10% higher than with other powder metallurgy processes.\nEquipment.\nThere are many types of equipment used in isostatic powder compacting. There is the mold containing the part, which is flexible, a flexible outer pressure mold that contains and seals the mold, and the machine delivering the pressure. There are also devices to control the amount of pressure and how long the pressure is held. The machines need to apply pressures from for metals.\nGeometrical possibilities.\nTypical workpiece sizes range from to thick and to long. It is possible to compact workpieces that are between and thick and to long.\nTool style.\nIsostatic tools are available in three styles, free mold (wet-bag), coarse mold (damp-bag) and fixed mold (dry-bag). The free mold style is the traditional style of isostatic compaction and is not generally used for high production work. In free mold tooling the mold is removed and filled outside the canister. Damp bag is where the mold is located in the canister, yet filled outside. In fixed mold tooling, the mold is contained within the canister, which facilitates automation of the process.\nHot isostatic pressing.\nHot isostatic pressing (HIP) compresses and sinters the part simultaneously by applying heat ranging from 900 °F (480 °C) to 2250 °F (1230 °C). Argon gas is the most common gas used in HIP because it is an inert gas, thus prevents chemical reactions during the operation.\nCold isostatic pressing.\nCold isostatic pressing (CIP) uses fluid as a means of applying pressure to the mold at room temperature. After removal the part still needs to be sintered.\nIt is helpful in distributing pressure uniformly over the compaction material contained in a rubber bag.\nDesign considerations.\nAdvantages over standard powder compaction are the possibility of thinner walls and larger workpieces. Height to diameter ratio has no limitation. No specific limitations exist in wall thickness variations, undercuts, reliefs, threads, and cross holes. No lubricants are need for isostatic powder compaction. The minimum wall thickness is 0.05 inches (1.27 mm) and the product can have a weight between 40 and 300 pounds (18 and 136 kg). There is 25 to 45% shrinkage of the powder after compacting.\nSintering.\nAfter compaction, powdered materials are heated in a controlled atmosphere in a process known as sintering. During this process, the surfaces of the particles are bonded and desirable properties are achieved.\nSintering of powder metals is a process in which particles under pressure chemically bond to themselves in order to form a coherent shape when exposed to a high temperature. The temperature in which the particles are sintered is most commonly below the melting point of the main component in the powder. If the temperature is above the melting point of a component in the powder metal part, the liquid of the melted particles fills the pores. This type of sintering is known as liquid-state sintering. A major challenge with sintering in general is knowing the effect of the process on the dimensions of the compact particles. This is especially difficult for tooling purposes in which specific dimensions may be needed. It is most common for the sintered part to shrink and become denser, but it can also expand or experience no net change.\nThe main driving force for solid state sintering is an excess of surface free energy. The process of solid-state sintering is complex and dependent on the material and furnace (temperature and gas) conditions. There are six main stages that sintering processes can be grouped in which may overlap with one another: 1 initial bonding among particles, 2) neck growth, 3) pore channel closure, 4) pore rounding, 5) densification or pore shrinkage, and 6) pore coarsening. The main mechanisms present in these stages are evaporation, condensation, grain boundaries, volume diffusion, and plastic deformation.\nMost sintering furnaces contain three zones with three different properties that help to carry out the six steps above. The first zone, commonly coined the burn-off or purge stage, is designed to combust air, burn any contaminants such as lubricant or binders, and slowly raise the temperature of the compact materials. If the temperature of the compact parts is raised too quickly, the air in the pores will be at a very high internal pressure which could lead to expansion or fracture of the part. The second zone, known as the high-temperature stage, is used to produce solid-state diffusion and particle bonding. The material is seeking to lower its surface energy and does so by moving toward the points of contact between particles. The contact points become larger and eventually a solid mass with small pores is created. The third zone, also called the cooling period, is used to cool down the parts while still in a controlled atmosphere. This is an important zone as it prevents oxidation from immediate contact with the air or a phenomenon known as rapid cooling. All of the three stages must be carried out in a controlled atmosphere containing no oxygen. Hydrogen, nitrogen, dissociated ammonia, and cracked hydrocarbons are common gases pumped into the furnace zones providing a reducing atmosphere, preventing oxide formation.\nDuring this process, a number of characteristics are increased including the strength, ductility, toughness, and electrical and thermal conductivity of the material. If different elemental powders are compact and sintered, the material would form into alloys and intermetallic phases.\nAs the pore sizes decrease, the density of the material will increase. As stated above, this shrinkage is a huge problem in making parts or tooling in which particular dimensions are required. The shrinkage of test materials is monitored and used to manipulate the furnace conditions or to oversize the compact materials in order to achieve the desired dimensions. Although, sintering does not deplete the compact part of porosity. In general, powder metal parts contain five to twenty-five percent porosity after sintering.\nTo allow efficient stacking of product in the furnace during sintering and prevent parts sticking together, many manufacturers separate ware using ceramic powder separator sheets. These sheets are available in various materials such as alumina, zirconia, and magnesia. They are also available in fine, medium, and coarse particle sizes. By matching the material and particle size to the wares being sintered, surface damage and contamination can be reduced, while maximizing furnace loading per batch.\nOne recently developed technique for high-speed sintering involves passing high electric current through a powder to preferentially heat the asperities. Most of the energy serves to melt that portion of the compact where migration is desirable for densification; comparatively little energy is absorbed by the bulk materials and forming machinery. Naturally, this technique is not applicable to electrically insulating powders.\nContinuous powder processing.\nThe phrase \"continuous process\" should be used only to describe modes of manufacturing which could be extended indefinitely in time. Normally, however, the term refers to processes whose products are much longer in one physical dimension than in the other two. Compression, rolling, and extrusion are the most common examples.\nIn a simple compression process, powder flows from a bin onto a two-walled channel and is repeatedly compressed vertically by a horizontally stationary punch. After stripping the compress from the conveyor, the compacted mass is introduced into a sintering furnace. An even easier approach is to spray powder onto a moving belt and sinter it without compression. However, good methods for stripping cold-pressed materials from moving belts are hard to find. One alternative that avoids the belt-stripping difficulty altogether is the manufacture of metal sheets using opposed hydraulic rams, although weakness lines across the sheet may arise during successive press operations.\nPowders can also be rolled to produce sheets. The powdered metal is fed into a two-high rolling mill, and is compacted into strip form at up to . The strip is then sintered and subjected to another rolling and further sintering. Rolling is commonly used to produce sheet metal for electrical and electronic components, as well as coins. Considerable work also has been done on rolling multiple layers of different materials simultaneously into sheets.\nExtrusion processes are of two general types. In one type, the powder is mixed with a binder or plasticizer at room temperature; in the other, the powder is extruded at elevated temperatures without fortification. Extrusions with binders are used extensively in the preparation of tungsten-carbide composites. Tubes, complex sections, and spiral drill shapes are manufactured in extended lengths and diameters varying in the range . Hard metal wires of diameter have been drawn from powder stock. At the opposite extreme, large extrusions on a tonnage basis may be feasible.\nFor softer, easier to form metals such as aluminium and copper alloys continuous extrusion may also be performed using processes such as conform or continuous rotary extrusion. These processes use a rotating wheel with a groove around its circumference to drive the loose powder through a forming die. Through a combination of high pressure and a complex strain path the powder particles deform, generate a large amount of frictional heat and bond together to form a bulk solid. Theoretically fully continuous operation is possible as long as the powder can be fed into the process.\nThere appears to be no limitation to the variety of metals and alloys that can be extruded, provided the temperatures and pressures involved are within the capabilities of die materials. Extrusion lengths may range from 3 to 30 m and diameters from 0.2 to 1 m. Modern presses are largely automatic and operate at high speeds (on the order of m/s).\nShock (dynamic) consolidation.\nShock consolidation, or dynamic consolidation, is an experimental technique of consolidating powders using high pressure shock waves. These are commonly produced by impacting the workpiece with an explosively accelerated plate. Despite being researched for a long time, the technique still has some problems in controlability and uniformity. However, it offers some valuable potential advantages. As an example, consolidation occurs so rapidly that metastable microstructures may be retained.\nElectric current assisted sintering.\nThese techniques employ electric currents to drive or enhance sintering. Through a combination of electric currents and mechanical pressure powders sinter more rapidly thereby reducing the sintering time compared to conventional thermal solutions. The techniques can be divided into two main categories: resistance sintering, which incorporates spark plasma sintering and hot pressing; and electric discharge sintering, such as capacitor discharge sintering or its derivative, electro sinter forging. Resistance sintering techniques are consolidation methods based on temperature, where heating of the mold and of the powders is accomplished through electric currents, usually with a characteristic processing time of 15 to 30 minutes. On the other hand, electric discharge sintering methods rely on high-density currents (from 0.1 to 1 kA/mm^2) to directly sinter electrically conductive powders, with a characteristic time between tens of microseconds to hundreds of milliseconds.\nSpecial products.\nMany special products are possible with powder metallurgy technology. A nonexhaustive list includes Al2O3 whiskers coated with very thin oxide layers for improved refraction; iron compacts with Al2O3 coatings for improved high-temperature creep strength; light bulb filaments made with powder technology; linings for friction brakes; metal glasses for high-strength films and ribbons; heat shields for spacecraft reentry into Earth's atmosphere; electrical contacts for handling large current flows; magnets; microwave ferrites; filters for gases; and bearings which can be infiltrated with lubricants.\nExtremely thin films and tiny spheres exhibit high strength. One application of this observation is to coat brittle materials in whisker form with a submicrometre film of much softer metal (e.g. cobalt-coated tungsten). The surface strain of the thin layer places the harder metal under compression, so that when the entire composite is sintered the rupture strength increases markedly. With this method, strengths on the order of 2.8 GPa versus 550 MPa have been observed for, respectively, coated (25% cobalt) and uncoated tungsten carbides.\nHazards.\nThe special materials and processes used in powder metallurgy can pose hazards to life and property. The high surface-area-to-volume ratio of the powders can increase their chemical reactivity in biological exposures (for example, inhalation or ingestion), and increases the risk of dust explosions. Materials considered relatively benign in bulk can pose special toxicological risks when in a finely divided form. Inhalation of heavy metals can result in many health issues. Lead and cadmium are generally toxic, and cobalt can cause asthma and fibrosis in sensitive individuals.", "Engineering,_Manufacturing": 1.0000077486, "qwen": "Yes"}
{"id": "64004864", "revid": "36069288", "url": "https://en.wikipedia.org/wiki?curid=64004864", "title": "Reishauer", "text": " \nReishauer is a Swiss machine tool builder based in Wallisellen, which manufactures gear grinding machines.\nThe company was founded in 1788 by the toolmaker Hans Jakob Däniker as a craft enterprise in Zurich. In 1870, the company was officially registered as a tool factory. In 1945, the first continuous generating gear grinding machine, ZA, was launched on the market, introducing a form of gear grinding that is today known as the Reishauer process. Soon after this, production expanded to gear parts outside machine-tool-engineering and met the requirements of the aircraft industry and the automotive industry. Reishauer AG is a subsidiary of Reishauer Beteiligungen AG, to which the German Felsomat AG has been a part of since 2010. The most important customers are the automotive industry and its suppliers.\nReishauer manufactures: gear grinding machines, grinding and dressing tools, clamping systems, and automation solutions. All components are supplied from one source with more than 80% vertical integration. Reishauer describes its performance system as a Circle of Competence, in which all machine components, tooling, and automation are manufactured in-house.\nHistory.\nFoundation as a toolmaker (from 1788).\nThe company was founded in 1788 by the toolmaker Hans Jakob Däniker as a craft enterprise in Zurich. Däniker's son Gottfried Reishauer trained as a toolmaker in the business and took over the management in 1824. In 1870, the company was officially registered as a tool factory. In 1882, the \"Aktiengesellschaft für Fabrikation Reishauer'scher Werkzeuge\" was founded, and the portfolio was expanded to include thread gauges in addition to thread cutting tools.\nThe step to mechanical engineering (from 1924).\nAs the thread grinding machines that were currently available on the market did not meet Reishauer's requirements, they designed their own thread grinding machine in 1924. The \"RK Gewinde\" started to work in the factory in 1928 and marked the step towards becoming a machine tool manufacturer. In 1931, the first in-house made machine for grinding taps was put into operation. Soon Reishauer began to produce the machines not only for his own needs but also to sell them to other companies. This enabled the company to bridge the declining demand for tools in the years after 1929.\nThe introduction of the continuous generating grinding process and the rise to become an international company (from 1945).\nIn 1945, the first continuous generating gear grinding machine, ZA, was launched on the market, introducing a form of gear grinding, today known as the Reishauer process. This machine had been preceded by a 15-year development period, as Reishauer wanted to find a more accurate, faster, and cheaper method of manufacturing gears. 1968, the AZA, a new gear grinding machine, was produced. The AZA was based on the same continuous generating process but allowed one person to operate several grinders at the same time, thanks to streamlining the operating process. Reishauer thus took the first step towards automating the gear grinding process. At the same time, production at Reishauer’s customers expanded to gear parts outside machine tool engineering, andt included gears for printing machines, trucks, tractors, and pumps. The electronic generating gearbox, introduced in 1977 with the RZ300E, ensured a level of precision that met the requirements of the aircraft industry. In 1986, the RZ301S enhanced generating grinding with shift grinding, which enabled constant grinding forces and higher profile accuracy. In 1993, the RZ362A, the first high-performance gear grinding machine, made its entry into the automotive industry. With this machine, Reishauer introduces the Low Noise Shifting (LNS) process, which reduced unwanted gear noise. In 1998, the company started its own diamond tool production and laid the foundation for its performance system, the Circle of Competence.\nUniversal machine and technological development (from 2001).\nIn 2001, the RZ400, the first universal machine, was launched on the market. It included the electronic generating gearbox developed by Reishauer with interfering signal suppression and extremely high drive rigidity. Furthermore, the RZ400 featured a Windows user interface, safety monitoring of the drive axes, and grinding at 63 m/s cutting speed and dressing of and grinding with multi-start threaded grinding wheels. With the RZ150, developed in 2003, two-spindle technology was introduced, which achieved a further increase in productivity. The machine was specially designed for automotive transmission gears. 2006 saw the launch of the RZ1000, which, just like the RZ400, was particularly adapted to job shops.\nIn 2008, Reishauer started the production of vitrified grinding wheels and built a new fully automated plant for this purpose in Pfaffnau, the canton of Lucerne, Switzerland. In 2009, the RZ60 series (RZ60, 160, 260) was designed, mainly for the automotive industry, but also for job shops, and further increased the productivity of the Reishauer process. In 2010, Reishauer started the development of clamping devices, which were launched in 2012. In 2014, Reishauer automation was introduced as part of the company's own performance system.\nCorporate structure.\nReishauer AG is a subsidiary of Reishauer Beteiligungen AG, to which the German Felsomat AG has been part since 2010. The most important customers are the automotive industry and its suppliers. Reishauer has branches in Germany, France, Japan, China, and the USA.\nProducts.\nReishauer manufactures gear grinding machines, grinding and dressing tools, clamping systems, and automation solutions. All components are supplied from one source with more than 80% vertical integration. Machines specifically customized for each customer. Reishauer offers complete systems for the production of high-quality gears, including loading and unloading systems for its gear grinding machines. Almost 100% of the products are exported. Reishauer describes its performance system as a Circle of Competence, in which all machine components, tooling, and automation are manufactured in-house.\nSee also.\n ", "Engineering,_Manufacturing": 0.9999790192, "qwen": "Yes"}
{"id": "28926460", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=28926460", "title": "Ethernet Exchange", "text": "Ethernet exchange is a physical network infrastructure through which Ethernet service providers, carriers and Internet service providers exchange Ethernet traffic between their networks. The Ethernet exchange was created as a neutral meeting place where wireless carriers can connect to multiple Ethernet services in several markets that need access to specific locations though one connection. As service providers and operators continue to grow, they need a network to support the increasing amount of data and video on mobile networks. Thus, allowing Ethernet sellers connecting to an Ethernet exchange immediate access to the buyers and a more basic technical process.\nEthernet exchanges offer an accelerated system for carriers and worldwide service providers to extend market reach and coverage. Many carriers and service providers have adopted this technology due to the refined administration features and lower costs when compared to older wholesale Ethernet interconnectivity solutions.", "Engineering,_Manufacturing": 1.000002861, "qwen": "Yes"}
{"id": "2899216", "revid": "33011235", "url": "https://en.wikipedia.org/wiki?curid=2899216", "title": "CAD data exchange", "text": "CAD data exchange is a method of drawing data exchange used to translate between different computer-aided design (CAD) authoring systems or between CAD and other downstream CAx systems.\nMany companies use different CAD systems and exchange CAD data file format with suppliers, customers, and subcontractors. Such formats are often proprietary. Transfer of data is necessary so that, for example, one organization can be developing a CAD model, while another performs analysis work on the same model; at the same time a third organization is responsible for manufacturing the product.\nSince the 1980s, a range of different CAD technologies have emerged. They differ in their application aims, user interfaces, performance levels, and in data structures and data file formats. For interoperability purposes a requirement of accuracy in the data exchange process is of paramount importance and robust exchange mechanisms are needed.\nThe exchange process targets primarily the geometric information of the CAD data but it can also target other aspects such as metadata, knowledge, manufacturing information, tolerances and assembly structure.\nThere are three options available for CAD data exchange: direct model translation, neutral file exchange and third-party translators.\nCAD data content.\nAlthough initially targeted for the geometric information (wire frame, surfaces, solids and drawings) of a product, nowadays there are other pieces of information that can be retrieved from a CAD file:\nThe different types of product information targeted by the exchange process may vary throughout the life cycle of the product. At earlier stages of the design process, more emphasis is given to the geometric and design intent aspects of the data exchange while metadata and application data are more important at later stages of the product and process development.\nData exchange options.\nThere are at least three ways to exchange data between different CAD system: via a hardcopy or image (e.g. TIFF, GIF, JPEG, BMP or PCX, by way of image tracing), CAD-neutral formats or third-party CAD file translators between proprietary file formats. All have their advantages and disadvantages and may be error-prone.\nDirect model translation.\nDirect data translators provide a direct solution which entails translating the data stored in a product database directly from one CAD system format to another, usually in one step. There usually exists a neutral database in a direct data translator. The structure of the neutral database must be general, governed by the minimum required definitions of any of the modelling data types, and be independent of any vendor format. Major CAD systems, such as SolidWorks, PTC Creo, Siemens NX and CATIA can directly read and/or write other CAD formats, simply by using \"File Open\" and \"File Save As\" options. This option is limited by the fact that most CAD formats are proprietary therefore direct translators are typically unidirectional, partially functional and not standardized.\nNeutral file exchange.\nNeutral file exchange uses an intermediary neutral format to translate data between CAD systems. This method starts from a pre-processor embedded in the original CAD system, which generates the neutral file from the originating CAD format. The target CAD system post-processes the neutral file and converts it into the target native format. Some neutral formats are defined by standards organizations such as IGES and STEP while others are proprietary but still widely used and are regarded as quasi industry standards.\nThird-party translators.\nSeveral companies specialize in CAD data translation software that can read from one CAD system and write the information in another CAD system format. There are a handful of companies that provide low-level software toolkits to directly read and write the major CAD file formats. Most CAD developers license these toolkits, to add import and export capabilities to their products. There are also a significant number of companies that use the low-level translation toolkits as the basis for building standalone end-user translation and validation applications. These systems have their own proprietary intermediate format some of which will allow reviewing the data during translation. Some of these translators work stand-alone while others require one or both of the CAD packages installed on the translation machine as they use code (APIs) from these systems to read/write the data.\nSome companies also use these low-level toolkits to create import or export plug-ins for other CAD applications.\nData exchange quality.\nData quality can be addressed intrinsically and extrinsically. Intrinsic problems are those related to the CAD model’s structure before any translation process begins, while extrinsic problems relate to those issues appearing during translation. The development of STEP is the best solution to solve the extrinsic problems, extending its current capabilities to support 2-D parametric sections, 3-D parametric assemblies, and history-based modeling. Product data quality is a key issue to avoid intrinsic data exchange problems and simplify the integration of downstream applications in the design chain.\nAs each CAD system has its own method of describing geometry, both mathematically and structurally, there is always some loss of information when translating data from one CAD data format to another. One example is when the translation occurs between CAD systems using different geometric modeling kernels, in which the translation inconsistencies can lead to anomalies in the data. The intermediate file formats are also limited in what they can describe, and they can be interpreted differently by both the sending and receiving systems. It is, therefore, important when transferring data between systems to identify what needs to be translated. If only the 3D model is required for the downstream process, then only the model description needs to be transferred. However, there are levels of detail. For example: is the data wireframe, surface, or solid; is the topology (BREP) information required; must the face and edge identifications be preserved on subsequent modification; must the feature information and history be preserved between systems; and is PMI annotation to be transferred. With product models, retaining the assembly structure may be required. If drawings need to be translated, the wireframe geometry is normally not an issue; however text, dimensions and other annotation can be an issue, particularly fonts and formats. No matter what data is to be translated, there is also a need to preserve attributes (such as color and layer of graphical objects) and metadata stored within the files.\nSome translation methods are more successful than others at translating data between CAD systems. Native formats offer the simple translation of 3D solids, but even so there are few pitfalls to watch out for. If two CAD systems use different representations for one type of geometry at some point the representation must be converted or even discarded, regardless of the type of translation. Modern Neutral formats are designed to solve this problem.\nOld neutral formats like IGES can have some translation issues like loss of the original color of the parts, or incorrect position of bodies.\nThis is no longer the case with modern standards like STEP AP242, which embeds Validation Properties. Validation Properties are key characteristics of the model (Center of Gravity of a solid, wet area of a surface, PMI characteristics or even check points on a shape), stored by the emitting system and checked by the receiving system. This allows to control the quality of the imported data. \nQuality of exchange using STEP is so important that regular benchmarks are run by independent associations (AFNeT, PDES, inc., ProSTEP iViP) to check exchanges between various CAD and PLM systems.\nSome CAD systems have functionalities to compare geometry of two models. So, user can compare the model before and after translation from one CAD to another one to estimate quality of the translation, and to fix found defects. But often such functionalities can compare only tessellations of two models. It is really hard algorithmic problem to compare topological elements of two 3D models and restore their associativity to show groups of modified faces, because there are very different representation of geometry data in different CAD systems, but sometimes it is possible. For instance, the component LEDAS Geometry Comparison based on C3D kernel can be integrated in CAD system (like Autodesk Inventor,) to compare 3D models and pinpoint all of the differences between them.\nMultiCAD Digital Mockups.\nTwo CAD/CAM/CAE PLM trends have been driving CAD Data Exchange technology. One is the need for close interaction throughout today’s extended multiCAD enterprises. The other is the increased reliance on digital mockups to permit visualization, design in context, simulation and analysis of large scale assemblies prior to the actual manufacture of the physical product. Ongoing advances in data exchange technology have enabled significant fulfillment of those needs.\nThe ability to visualize medium if not large scale assemblies was one of the early successes of these CAD translation formats. Hardware improvements and the development of lightweight formats supported larger scale assemblies.\nCurrent advances now allow an “Active Mockup.” This technology allows design in context with simulations such as dynamic clearance analysis and automatic generation of motion envelopes. Active mockups allow the edit of components from directly within the multi-CAD assembly. Multiple level-of-detail displays support interactive performance even in huge assemblies.\nCAD to CAM Data Exchange.\nNC programming typically requires that the geometry received from a CAD system, whether in wireframe, surface, solid or combined formats, be free from any irregularities and inconsistencies that may have occurred in the CAD phase of geometry creation. Data exchange from CAD to CAM must therefore include tools for identifying and repairing those inconsistencies. These tools are typically included in the data exchange software of each CAM solution-set.\nIn a true PLM environment, CAD to CAM data exchange must provide for more than the transfer of geometry. Product Manufacturing Information, whether generated by the designer for use by manufacturing, or generated by the manufacturing organization for use by design, must be a part of the data exchange system. STEP-NC was designed to carry GD&T and other PMI through CAD and CAM into a CNC.", "Engineering,_Manufacturing": 0.9999507666, "qwen": "Yes"}
{"id": "4904260", "revid": "575347", "url": "https://en.wikipedia.org/wiki?curid=4904260", "title": "Log house moulder", "text": "A log house moulder is a machine to prepare logs to be suitable for building a log home. In general, the logs are first sawn to a square beam, then the moulder makes the groove. Often fitted to a portable sawmill that enables direct profiling of round or squared logs. The log house moulder is usually powered by electricity, but for portable sawmills they are sometimes using a chainsaw as power head. One of the more common, especially in Europe, is the\nLogosol log house moulder.\nOther type of log house moulder is a log through-pass machine. Through-pass log home moulders are highly productive and mighty machines able to turn truck load of logs into house logs during a work shift. Barked or debarked green or dry logs are fed into such machine one after other on one side and the machine processes logs, turning them into profiled roundish or squarish house logs, taken from outfeed of the machine. Such log home milling machine can shape logs into different profiles: Swedish cope, Tongue&groove, D-log, bevel-edged logs, etc.\nOne of moulders of through-pass type are Woodlandia' Rotary Log Moulders (USA, Canada, Russia)", "Engineering,_Manufacturing": 0.9966534376, "qwen": "Yes"}
{"id": "5633026", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=5633026", "title": "Fixture (tool)", "text": "A fixture is a work-holding or support device used in the manufacturing industry. Fixtures are used to securely locate (position in a specific location or orientation) and support the work, ensuring that all parts produced using the fixture will maintain conformity and interchangeability. Using a fixture improves the economy of production by allowing smooth operation and quick transition from part to part, reducing the requirement for skilled labor by simplifying how workpieces are mounted, and increasing conformity across a production run.\nCompared with a jig.\nA fixture differs from a jig in that when a fixture is used, the tool must move relative to the workpiece; a jig moves the piece while the tool remains stationary.\nPurpose.\nA fixture's primary purpose is to create a secure mounting point for a workpiece, allowing for support during operation and increased accuracy, precision, reliability, and interchangeability in the finished parts. It also serves to reduce working time by allowing quick set-up, and by smoothing the transition from part to part. It frequently reduces the complexity of a process, allowing for unskilled workers to perform it and effectively transferring the skill of the tool maker to the unskilled worker. Fixtures also allow for a higher degree of operator safety by reducing the concentration and effort required to hold a piece steady.\nEconomically speaking the most valuable function of a fixture is to reduce labor costs. Without a fixture, operating a machine or process may require two or more operators; using a fixture can eliminate one of the operators by securing the workpiece.\nDesign.\nFixtures should be designed with economics in mind; the purpose of these devices is often to reduce costs, and so they should be designed in such a way that the cost reduction outweighs the cost of implementing the fixture. It is usually better, from an economic standpoint, for a fixture to result in a small cost reduction for a process in constant use, than for a large cost reduction for a process used only occasionally.\nMost fixtures have a solid component, affixed to the floor or to the body of the machine and considered immovable relative to the motion of the machining bit, and one or more movable components known as clamps. These clamps (which may be operated by many different mechanical means) allow workpieces to be easily placed in the machine or removed, and yet stay secure during operation. Many are also adjustable, allowing for workpieces of different sizes to be used for different operations. Fixtures must be designed such that the pressure or motion of the machining operation (usually known as the feed) is directed primarily against the solid component of the fixture. This reduces the likelihood that the fixture will fail, interrupting the operation and potentially causing damage to infrastructure, components, or operators.\nFixtures may also be designed for very general or simple uses. These multi-use fixtures tend to be very simple themselves, often relying on the precision and ingenuity of the operator, as well as surfaces and components already present in the workshop, to provide the same benefits of a specially-designed fixture. Examples include workshop vises, adjustable clamps, and improvised devices such as weights and furniture.\nEach component of a fixture is designed for one of two purposes: location or support.\nLocation.\nLocating components ensure the \"geometrical stability\" of the workpiece. They make sure that the workpiece rests in the correct position and orientation for the operation by addressing and impeding all the degrees of freedom the workpiece possesses.\nFor locating workpieces, fixtures employ pins (or \"buttons\"), clamps, and surfaces. These components ensure that the workpiece is positioned correctly, and remains in the same position throughout the operation. Surfaces provide support for the piece, pins allow for precise location at low surface area expense, and clamps allow for the workpiece to be removed or its position adjusted. Locating pieces tend to be designed and built to very tight specifications.\nSupport.\nIn designing the locating parts of a fixture, only the \"direction\" of forces applied by the operation are considered, and not their \"magnitude\". Locating parts technically support the workpiece, but do not take into account the strength of forces applied by the process and so are usually inadequate to actually secure the workpiece during operation. For this purpose, support components are used.\nTo secure workpieces and prevent motion during operation, support components primarily use two techniques: positive stops and friction. A positive stop is any immovable component (such as a solid surface or pin) that, by its placement, physically impedes the motion of the workpiece. Support components are more likely to be adjustable than locating components, and normally do not press tightly on the workpiece or provide absolute location.\nSupport components usually bear the brunt of the forces delivered during the operation. To reduce the chances of failure, support components are usually not also designed as clamps.\nFor example: 2 heavy metal parts are to be joined with screws and arc welding. Using a fixture will help secure the two separate parts in a designated area for the craftsman to complete the job easily & without the risk of injury.\nTypes of fixtures.\nFixtures are usually classified according to the machine for which they were designed. The most common two are \"milling fixtures\" and \"drill fixtures\".\nMilling fixtures.\nMilling operations tend to involve large, straight cuts that produce many chips and involve varying force. Locating and supporting areas must usually be large and very sturdy in order to accommodate milling operations; strong clamps are also a requirement. Due to the vibration of the machine, positive stops are preferred over friction for securing the workpiece. For high-volume automated processes, milling fixtures usually involve hydraulic or pneumatic clamps.\nDrilling fixtures.\nDrilling fixtures cover a wider range of different designs and procedures than milling fixtures. Though workholding for drills is more often provided by jigs, fixtures are also used for drilling operations.\nTwo common elements of drilling fixtures are the hole and bushing. Holes are often designed into drilling fixtures, to allow space for the drill bit itself to continue through the workpiece without damaging the fixture or drill, or to guide the drill bit to the appropriate point on the workpiece. Bushings are simple bearing sleeves inserted into these holes to protect them and guide the drill bit.\nBecause drills tend to apply force in only one direction, support components for drilling fixtures may be simpler. If the drill is aligned pointing down, the same support components may compensate for the forces of both the drill and gravity at once. However, though monodirectional, the force applied by drills tends to be concentrated on a very small area. Drilling fixtures must be designed carefully to prevent the workpiece from bending under the force of the drill.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "5639123", "revid": "37416313", "url": "https://en.wikipedia.org/wiki?curid=5639123", "title": "1984–85 UEFA Cup", "text": "The 1984–85 UEFA Cup was the 14th season of the UEFA Cup. It was won by Real Madrid, who gained an aggregate victory over Videoton of Hungary in a two-legged final.\nFirst round.\nSecond leg.\n\"Videoton won 1–0 on aggregate.\"\n\"Queens Park Rangers won 7–0 on aggregate.\"\n\"1–1 on aggregate; Universitatea Craiova won 5–3 on penalties.\"\n\"Lokomotive Leipzig won 7–3 on aggregate.\"\n\"Köln won 3–1 on aggregate.\"\n\"Željezničar won 5–2 on aggregate.\"\n\"Spartak Moskva won 7–2 on aggregate.\"\n\"Dinamo Minsk won 10–0 on aggregate.\"\n\"Partizan won 4–0 on aggregate.\"\n\"Rijeka won 4–2 on aggregate.\"\n\"CSKA Septemvriysko Zname won 4–3 on aggregate.\"\n\"Bohemians ČKD Praha won 8–3 on aggregate.\"\n\"Manchester United won 5–2 on aggregate.\"\n\"PSV Eindhoven won 3–2 on aggregate.\"\n\"Widzew Łódź won 2–1 on aggregate.\"\n\"Fiorentina won 3–0 on aggregate.\"\n\"Borussia Mönchengladbach won 7–3 on aggregate.\"\n\"Standard Liège won 3–1 on aggregate.\"\n\"Club Brugge won 1–0 on aggregate.\"\n\"Olympiacos won 3–2 on aggregate.\"\n\"Linzer ASK won 2–0 on aggregate.\"\n\"Real Madrid won 5–2 on aggregate.\"\n\"Hamburg won 2–0 on aggregate.\"\n\"Sporting CP won 4–2 on aggregate.\"\n\"Ajax won 14–0 on aggregate.\"\n\"Dundee United won 3–1 on aggregate.\"\n\"Rangers won 4–3 on aggregate.\"\n\"Paris Saint-Germain won 6–2 on aggregate.\"\n\"2–2 on aggregate; Anderlecht won on away goals.\"\n\"Internazionale won 2–1 on aggregate.\"\n\"Sion won 4–2 on aggregate.\"\n\"Tottenham Hotspur won 9–0 on aggregate.\"\nSecond round.\nSecond leg.\n\"Spartak Moskva won 3–1 on aggregate.\"\n\"2–2 on aggregate; Dinamo Minsk won 5–3 on penalties.\"\n\"1–1 on aggregate; Bohemians ČKD Praha won 4–2 on penalties.\"\n\"3–3 on aggregate; Widzew Łódź won on away goals.\"\n\"Hamburg won 6–1 on aggregate.\"\n\"6–6 on aggregate; Partizan won on away goals.\"\n\"Universitatea Craiova won 2–0 on aggregate.\"\n\"Anderlecht won 7–3 on aggregate.\"\n\"Željezničar won 3–2 on aggregate.\"\n\"Köln won 4–1 on aggregate.\"\n\"Internazionale won 4–3 on aggregate.\"\n\"Dundee United won 7–2 on aggregate.\"\n\"Manchester United won 1–0 on aggregate.\"\n\"Tottenham Hotspur won 4–2 on aggregate.\"\n\"Real Madrid won 4–3 on aggregate.\"\n\"Videoton won 5–2 on aggregate.\"\nThird round.\nSecond leg.\n\"Željezničar won 4–2 on aggregate.\"\n\"Tottenham Hotspur won 3–1 on aggregate.\"\n\"Videoton won 5–2 on aggregate.\"\n\"Dinamo Minsk won 2–1 on aggregate.\"\n\"Köln won 2–1 on aggregate.\"\n\"2–2 on aggregate; Internazionale won on away goals.\"\n\"Manchester United won 5–4 on aggregate.\"\n\"Real Madrid won 6–4 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"1–1 on aggregate; Videoton won 5–4 on penalties.\"\n\"Željezničar won 3–1 on aggregate.\"\n\"Internazionale won 4–1 on aggregate.\"\n\"Real Madrid won 1–0 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Videoton won 4–3 on aggregate.\"\n\"Real Madrid won 3–2 on aggregate.\"\nFinal.\nSecond leg.\n\"Real Madrid won 3–1 on aggregate.\"", "Engineering,_Manufacturing": 0.9999988079, "qwen": "Yes"}
{"id": "5641682", "revid": "30380342", "url": "https://en.wikipedia.org/wiki?curid=5641682", "title": "1982–83 UEFA Cup", "text": "The 1982–83 UEFA Cup was the 12th edition of the UEFA Cup. It was won by Belgian club Anderlecht on 2–1 aggregate over Portuguese club Benfica.\nAssociation team allocation.\nA total of 64 teams from 31 UEFA member associations participate in the 1982–83 UEFA Cup. The association ranking based on the UEFA country coefficients is used to determine the number of participating teams for each association:\nAssociation ranking.\nFor the 1982–83 UEFA Cup, the associations are allocated places according to their 1981 UEFA country coefficients, which takes into account their performance in European competitions from 1976–77 to 1980–81. As Albania did not play, Italy obtained a special place.\nTeams.\nThe labels in the parentheses show how each team qualified for competition:\nFirst round.\nSecond leg.\n\"Sevilla won 6–1 on aggregate.\"\n\"Bohemians won 7–1 on aggregate.\"\n\"1–1 on aggregate; KSC Lokeren won on away goals.\"\n\"Corvinul Hunedoara won 4–1 on aggregate.\"\n\"Kaiserslautern won 6–0 on aggregate.\"\n\"Saint-Étienne won 4–1 on aggregate.\"\n\"FK Sarajevo won 6–4 on aggregate.\"\n\"Hajduk Split won 8–1 on aggregate.\"\n\"Baník Ostrava won 4–1 on aggregate.\"\n\"Śląsk Wrocław won 3–2 on aggregate.\"\n\"3–3 on aggregate; Viking won on away goals.\"\n\"Anderlecht won 6–1 on aggregate.\"\n\"IK Brage won 4–3 on aggregate.\"\n\"2–2 on aggregate; IFK Norrköping won on away goals.\"\n\"Bordeaux won 6–3 on aggregate.\"\n\"3–3 on aggregate; Werder Bremen won on away goals.\"\n\"Ferencvárosi won 3–2 on aggregate.\"\n\"HFC Haarlem won 5–4 on aggregate.\"\n\"2–2 on aggregate; PAOK won on away goals.\"\n\"Zürich won 3–2 on aggregate.\"\n\"Benfica won 4–2 on aggregate.\"\n\"Roma won 4–3 on aggregate.\"\n\"Rangers won 2–0 on aggregate.\"\n\"Dundee United won 3–1 on aggregate.\"\n\"2–2 on aggregate; Napoli won on away goals.\"\n\"Servette won 4–0 on aggregate.\"\n\"Spartak Moscow won 8–4 on aggregate.\"\n\"Universitatea Craiova won 3–2 on aggregate.\"\n\"Valencia won 2–1 on aggregate.\"\n\"Porto won 3–0 on aggregate.\"\n\"Shamrock Rovers won 7–0 on aggregate.\"\n\"Köln won 6–0 on aggregate.\"\nSecond round.\nFirst leg.\n\"See also Luzhniki disaster\"\n \nSecond leg.\n\"Universitatea Craiova won 5–0 on aggregate.\n\"FK Sarajevo won 8–4 on aggregate.\"\n\"Valencia won 1–0 on aggregate.\"\n \n\"Bohemians won 4–0 on aggregate.\"\n\"Werder Bremen won 8–2 on aggregate.\"\n\"1–1 on aggregate. Roma won 4–2 on penalties.\"\n\"Benfica won 4–1 on aggregate.\"\n\"Bordeaux won 5–4 on aggregate.\"\n\"FC Zürich won 2–1 on aggregate.\"\n\"Kaiserslautern won 4–1 on aggregate.\"\n\"Köln won 6–2 on aggregate.\"\n\"Spartak Moscow won 5–1 on aggregate.\"\n\"Dundee United won 3–1 on aggregate.\"\n\"Sevilla won 4–2 on aggregate.\"\n\"Anderlecht won 6–3 on aggregate.\"\n\"Servette won 7–1 on aggregate.\"\nThird round.\nSecond leg.\n\"Universitatea Craiova won 2–1 on aggregate.\"\n\"Roma won 2–1 on aggregate.\"\n\"Anderlecht won 6–2 on aggregate.\"\n\"Bohemians won 4–3 on aggregate.\"\n\"Valencia won 2–0 on aggregate.\"\n\"Dundee United won 3–2 on aggregate.\"\n\"Kaiserslautern won 4–1 on aggregate.\"\n\"Benfica won 5–1 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"3–3 on aggregate; Universitatea Craiova won on away goals.\"\n\"Anderlecht won 5–2 on aggregate.\"\n\"Bohemians won 1–0 on aggregate.\"\n\"Benfica won 3–2 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"1–1 on aggregate; Benfica won on away goals.\"\n\"Anderlecht won 4–1 on aggregate\"\nFinal.\nSecond leg.\n\"Anderlecht won 2–1 on aggregate.\"", "Engineering,_Manufacturing": 0.9999990463, "qwen": "Yes"}
{"id": "5647246", "revid": "959742", "url": "https://en.wikipedia.org/wiki?curid=5647246", "title": "1979–80 UEFA Cup", "text": "The 1979–80 UEFA Cup was the ninth season of the UEFA Cup, a football competition organised by UEFA for clubs representing its member associations. The competitions was won by Eintracht Frankfurt, who beat Borussia Mönchengladbach on the away goals rule after a 3–3 aggregate draw in the final. All four semi-finalists came from West Germany, and a fifth was eliminated in the quarter-finals. This is the only time all four semi-finalists in a UEFA club competition came from a single nation.\nThe third club was revoked to Bulgaria and East Germany, and it was assigned to Czechoslovakia. The title holders obtained a place.\nFirst round.\nSecond leg.\n\"Zbrojovka Brno won 7–1 on aggregate.\"\n\"AGF won 2–1 on aggregate.\"\n\"Eintracht Frankfurt won 2–1 on aggregate.\"\n\"Aris Thessaloniki won 4–3 on aggregate.\"\n\"Dynamo Dresden won 5–1 on aggregate.\"\n\"Borussia Mönchengladbach won 4–1 on aggregate.\"\n\"Dinamo București won 12–0 on aggregate.\"\n\"1–1 on aggregate; Dundee United won on away goals.\"\n\"Bayern Munich won 4–2 on aggregate.\"\n\"Carl Zeiss Jena won 4–1 on aggregate.\"\n\"Dynamo Kyiv won 3–2 on aggregate.\"\n\"Grasshoppers won 6–0 on aggregate.\"\n\"Monaco won 3–2 on aggregate.\"\n\"Feyenoord won 2–0 on aggregate.\"\n\"Kaiserslautern won 8–2 on aggregate.\"\n\"Red Star Belgrade won 3–1 on aggregate.\"\n\"Standard Liège won 2–0 on aggregate.\"\n\"Inter Milan won 3–2 on aggregate.\"\n\"2–2 on aggregate; Keflavík won on away goals.\"\n\"Malmö FF won 4–1 on aggregate.\"\n\"Napoli won 2–1 on aggregate.\"\n\"Baník Ostrava won 6–2 on aggregate.\"\n\"Perugia won 1–0 on aggregate.\"\n\"Lokomotiv Sofia won 3–2 on aggregate.\"\n\"Diósgyőri VTK won 4–2 on aggregate.\"\n\"Ipswich Town won 10–1 on aggregate.\"\n\"Sporting CP won 2–0 on aggregate.\"\n\"PSV Eindhoven won 1–0 on aggregate.\"\n\"Leeds United won 7–0 on aggregate.\"\n\"2–2 on aggregate; Stuttgart won on away goals.\"\n\"Saint-Étienne won 4–2 on aggregate.\"\n\"Universitatea Craiova won 3–1 on aggregate.\"\nSecond round.\nSecond leg.\n\"Zbrojovka Brno won 5–2 on aggregate.\"\n\"Bayern Munich won 5–2 on aggregate.\"\n\"Aris Thessaloniki won 4–1 on aggregate.\"\n\"Borussia Mönchengladbach won 4–3 on aggregate.\"\n\"Eintracht Frankfurt won 3–2 on aggregate.\"\n\"Diósgyöri VTK won 4–1 on aggregate.\"\n\"1–1 on aggregate; Stuttgart won on away goals.\"\n\"Dynamo Kyiv won 2–1 on aggregate.\"\n\"Universitatea Craiova won 4–0 on aggregate.\"\n\"Feyenoord won 5–1 on aggregate.\"\n\"1–1 on aggregate; Grasshoppers won on away goals.\"\n\"Lokomotiv Sofia won 5–4 on aggregate.\"\n\"Saint-Étienne won 6–2 on aggregate.\"\n\"Red Star Belgrade won 6–4 on aggregate.\"\n\"Kaiserslautern won 3–1 on aggregate.\"\n\"Standard Liège won 3–2 on aggregate.\"\nThird round.\nSecond leg.\n\"Saint-Étienne won 7–4 on aggregate.\"\n\"Bayern Munich won 4–3 on aggregate.\"\n\"Borussia Mönchengladbach won 2–1 on aggregate.\"\n\"Kaiserslautern won 8–1 on aggregate.\"\n\"Eintracht Frankfurt won 4–2 on aggregate.\"\n\"Stuttgart won 5–0 on aggregate.\"\n\"2–2 on aggregate; Lokomotiv Sofia won on away goals.\"\n\"Zbrojovka Brno won 5–3 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"Bayern Munich won 4–2 on aggregate.\"\n\"Borussia Mönchengladbach won 6–1 on aggregate.\"\n\"Eintracht Frankfurt won 6–4 on aggregate.\"\n\"Stuttgart won 4–1 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Eintracht Frankfurt won 5–3 on aggregate.\"\n\"Borussia Mönchengladbach won 3–2 on aggregate.\"\nFinal.\nSecond leg.\n\"3–3 on aggregate; Eintracht Frankfurt won on away goals.\"", "Engineering,_Manufacturing": 0.9999701977, "qwen": "Yes"}
{"id": "5647479", "revid": "959742", "url": "https://en.wikipedia.org/wiki?curid=5647479", "title": "1978–79 UEFA Cup", "text": "The 1978–79 UEFA Cup was won by Borussia Mönchengladbach on aggregate over Red Star Belgrade.\nThe third club was revoked to Switzerland and Poland, and it was assigned to Bulgaria and East Germany.\nFirst round.\nFirst leg.\n\"Enzo Ferrero scored an olympic goal.\"\nSecond leg.\n\"Dukla Prague won 2–1 on aggregate.\"\n\"1–1 on aggregate. Milan won in a penalty shoot-out.\"\n\"Valencia won 5–3 on aggregate.\"\n\"Borussia Mönchengladbach won 7–2 on aggregate.\"\n\"Argeș Pitești won 5–1 on aggregate.\"\n\"Ajax won 3–2 on aggregate.\"\n\"Everton won 10–0 on aggregate.\"\n\"Lausanne-Sport won 2–0 on aggregate.\"\n\"Benfica won 2–0 on aggregate.\"\n\"Sporting Gijón won 3–1 on aggregate.\"\n\"Braga won 7–3 on aggregate.\"\n\"West Bromwich Albion won 6–2 on aggregate.\"\n\"6–6 on aggregate, Red Star Belgrade won on away goals rule.\"\n\"KuPS won 6–5 on aggregate.\"\n\"Stuttgart won 7–3 on aggregate.\"\n\"Torpedo Moscow won 7–3 on aggregate.\"\n\"Strasbourg won 4–3 on aggregate.\"\n\"MSV Duisburg won 10–2 on aggregate.\"\n\"Standard Liège won 1–0 on aggregate.\"\n\"Esbjerg won 1–0 on aggregate.\"\n\"Arsenal won 7–1 on aggregate.\"\n\"Carl Zeiss Jena won 3–2 on aggregate.\"\n\"1–1 on aggregate, ÍBV won on away goals rule.\"\n\"Manchester City won 4–3 on aggregate.\"\n\"Hibernian won 3–2 on aggregate.\"\n\"Politehnica Timișoara won 3–2 on aggregate.\"\n\"Śląsk Wrocław won 7–3 on aggregate.\"\n\"Levski Sofia won 4–3 on aggregate.\"\n\"Dinamo Tbilisi won 3–1 on aggregate.\"\n\"Hajduk Split won 3–2 on aggregate.\"\n\"Hertha BSC won 2–1 on aggregate.\"\n\"Budapest Honvéd won 8–2 on aggregate.\"\nSecond round.\nSecond leg.\n\"Ajax won 5–0 on aggregate.\"\n\"Budapest Honvéd won 4–2 on aggregate.\"\n\"2–2 on aggregate, Dukla Prague won on away goals rule.\"\n\"Valencia won 6–4 on aggregate.\"\n\"MSV Duisburg won 3–0 on aggregate.\"\n\"Stuttgart won 3–2 on aggregate.\"\n\"2–2 on aggregate, Arsenal won on away goals rule.\"\n\"Hertha BSC won 2–1 on aggregate.\"\n\"Śląsk Wrocław won 4–1 on aggregate.\"\n\"Esbjerg won 6–1 on aggregate.\"\n\"Manchester City won 4–2 on aggregate.\"\n\"Milan won 4–1 on aggregate.\"\n\"On 23 November 1978, UEFA fined Milan $14,000 for a bribery attempt to the Scottish referee John Gordon and linesmen Rollo Kyle and David McCartney (Italian club took the officials to shop for free the day before the game). Curiously, UEFA did not sanction the referee at all, however, Scottish Football Association suspended him.\"\n\"Strasbourg won 2–1 on aggregate.\"\n\"West Bromwich Albion won 3–0 on aggregate.\"\n\"Borussia Mönchengladbach won 2–0 on aggregate.\"\n\"Red Star Belgrade won 2–1 on aggregate.\"\nThird round.\nSecond leg.\n\"Manchester City won 5–2 on aggregate.\"\n\"Borussia Mönchengladbach won 5–3 on aggregate.\"\n\"Budapest Honvéd won 4–3 on aggregate.\"\n\"Hertha BSC won 5–2 on aggregate.\"\n\"MSV Duisburg won 4–0 on aggregate.\"\n\"Red Star Belgrade won 2–1 on aggregate.\"\n\"West Bromwich Albion won 3–1 on aggregate.\"\n\"Dukla Prague won 5–4 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"4–4 on aggregate, MSV Duisburg won on away goals rule.\"\n\"Hertha BSC won 3–2 on aggregate.\"\n\"Borussia Mönchengladbach won 4–2 on aggregate.\"\n\"Red Star Belgrade won 2–1 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Borussia Mönchengladbach won 6–3 on aggregate.\"\n\"2–2 on aggregate, Red Star Belgrade won on away goals rule.\"\nFinal.\nSecond leg.\n\"Borussia Mönchengladbach won 2–1 on aggregate.\"", "Engineering,_Manufacturing": 0.9997910857, "qwen": "Yes"}
{"id": "7303274", "revid": "5662528", "url": "https://en.wikipedia.org/wiki?curid=7303274", "title": "Novellus Systems", "text": "Novellus Systems Inc. was a company founded by Brad Mattson that developed, manufactured, sold, and serviced semiconductor equipment used in the fabrication of integrated circuits. It was a supplier of chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), electrochemical deposition (ECD), ultraviolet thermal processing (UVTP), and surface preparation equipment used in the manufacturing of semiconductors.\nNovellus Systems was founded in 1984 and is headquartered in San Jose, California. The company maintains engineering & manufacturing facilities in Tualatin, Oregon and San Jose, California. Also, Novellus has a component design and software development facility in Bangalore, India.\nIn December 2011, Novellus agreed to be acquired by Lam Research for $3.3 billion. The acquisition was completed in June 2012.\nProduct lines.\nNovellus' product lines were called ALTUS, ATHENA, GAMMA, INOVA, SABRE, SOLA, SPEED, and VECTOR, SEQUEL and assisted semiconductor companies with manufacturing.", "Engineering,_Manufacturing": 0.9186168313, "qwen": "Yes"}
{"id": "4325991", "revid": "910180", "url": "https://en.wikipedia.org/wiki?curid=4325991", "title": "Test engineer", "text": "A test engineer is a professional who determines how to create a process that would best test a particular product in manufacturing and related disciplines, in order to assure that the product meets applicable specifications. Test engineers are also responsible for determining the best way a test can be performed in order to achieve adequate test coverage. Often test engineers also serve as a liaison between manufacturing, design engineering, sales engineering and marketing communities as well.\nTest engineer expertises.\nTest engineers can have different expertise, which depends on what test process they are more familiar with (although many test engineers have full familiarity from the PCB level processes like ICT, JTAG, and AXI) to PCBA and system level processes like board functional test (BFT or FT), burn-in test, system level test (ST). Some of the processes used in manufacturing where a test engineer is needed are:\nEarly project involvement from design phase.\nIdeally, a test engineer's involvement with a product begins with the very early stages of the engineering design process, i.e. the requirements engineering stage and the design engineering stage. Depending on the culture of the firm, these early stages could involve a Product Requirements Document (PRD) and Marketing Requirements Document (MRD)—some of the earliest work done during a new product introduction (NPI).\nBy working with or as part of the NPI group, a test engineer ensures that a product is designed for both testability and manufacturability. In other words, to make sure that the product can be readily tested and built.\nThe following are some general rules to ensure testability and manufacturability of a product:\nBy following the general rules above, test engineers minimize future surprises (like adding extra components, re-layout of the boards, etc.) which drives up costs and development delays of the final product.\nWorking with cross platform teams, hardware and software team.\nOften people take shortcuts to be able to deliver final products. Because of these shortcuts, the product's manufacturability and testability becomes complicated (inability to read and write information, creating deviation from the process, etc.) which impacts the manufacturing complexity of a product. Because of this complexity, bottlenecks in the manufacturing and delivery schedule delays are introduced.\nWith this in mind, test engineers always get involved in the following reviews as well:\nYield maintenance.\nProducts' yield plays a very important part during their lifespan. There are usually three stages for a product, engineering, initial production (IP) and full production (FP). \nIn addition, yields will show if another process needs to be introduced (e.g., because processes already used cannot capture certain test errors). Yields can also decide if an existing test process can be trimmed down (step-wise or time-wise) or even fully eliminated. E.g., if the ESS errors can be captured during the 3rd hour, test time can be cut down from a normal 24 hours down to maybe 4. Or if a process consistently yields 100% during a 15-month period, teams can get together and decide to eliminate that process at all.\nTest automation.\nTest automation refers to the automation of the process to test a product through the use of machines. Depending on the product, the machines that we are referring to could mean a combination of Automatic Test Equipment (ATE), handler, interface board, and test program that drives the ATE, as with the case of the IC chip testing.\nTest automation is a big part of a test engineer's job.\nThe whole intention of automating the test is as follows:\nOverall, this drives manufacturing reliability and quality at the end of the line making sure that all units shipped out to customers are well tested, stressed, filtered out of any errors, and configured properly.\nDefining standard test documents.\nFollowing are some of the documents that the test engineers maintain or define:\nContract manufacturer.\nA contract manufacturer (CM) also provides a test engineer for their customers. The function of these test engineers varies depending on the level of support they provide for their customers: providing \"interactive and first level of defense\"-only support or providing partial or ground-up solutions.\nProviding interactive and first level-of-defense support.\nProviding \"interactive and first level-of-defense\"-only support is the usual job of the CM TE. Here are some typical job functions for a CM test engineer:\nBecause of their close involvement with the test line, they monitor the products going through the line and inspect the failed boards to decide if it really failed or if the failure was just caused by some improper test setup. Some examples of these false failures are:\nProviding partial or ground up solutions.\nThere is a small number of companies who prefer to outsource their test engineering work to their corresponding CM. In that case, the CM TEs will be in charge of providing the test automation solution, test fixture design, yield gathering plus the usual interactive and first level of defense for their customers.\nOf course, outsourcing test solutions to the CM has its pros and cons.\nSome of the advantages are:\nSome of the disadvantages are:\nBecause it is hard to find a test engineer who knows every aspect of testing methodology (from PCB tests like ICT, JTAG test, flying probe test, and X-Ray test to PCBA test which includes writing test automation from functional test to FQA test among others), companies usually outsource part of the development of this missing test piece to their CM. For example, if none of the in-house TEs know much about ICT fixtures, they will ask their CM to develop the ICT test solutions for them instead.", "Engineering,_Manufacturing": 0.9999235868, "qwen": "Yes"}
{"id": "28132162", "revid": "8331790", "url": "https://en.wikipedia.org/wiki?curid=28132162", "title": "Dicing tape", "text": "Dicing tape is a backing tape used during wafer dicing or some other microelectronic substrate separation, the cutting apart of pieces of semiconductor or other material following wafer or module microfabrication. The tape holds the pieces of the substrate, in case of a wafer called as die, together during the cutting process, mounting them to a thin metal frame. The dies/substrate pieces are removed from the dicing tape later on in the electronics manufacturing process.\nTape types.\nDicing tape can be made of PVC, polyolefin, or polyethylene backing material with an adhesive to hold the wafer or substrate in place. In some cases dicing tape will have a release liner that will be removed prior to mounting the tape to the backside of the wafers, with a variety of adhesive strengths, designed for various wafer/substrate sizes and materials.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1448709", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1448709", "title": "Gas tungsten arc welding", "text": "Gas tungsten arc welding (GTAW), also known as tungsten inert gas (TIG) welding, is an arc welding process that uses a non-consumable tungsten electrode to produce the weld. The weld area and electrode are protected from oxidation or other atmospheric contamination by an inert shielding gas (argon or helium). A filler metal is normally used, though some welds, known as \"autogenous welds\", or \"fusion welds\" do not require it. When helium is used, this is known as heliarc welding. A constant-current welding power supply produces electrical energy, which is conducted across the arc through a column of highly ionized gas and metal vapors known as a plasma. TIG welding is most commonly used to weld thin sections of stainless steel and non-ferrous metals such as aluminum, magnesium, and copper alloys. The process grants the operator greater control over the weld than competing processes such as shielded metal arc welding and gas metal arc welding, allowing stronger, higher-quality welds. However, TIG welding is comparatively more complex and difficult to master, and furthermore, it is significantly slower than most other welding techniques. A related process, plasma arc welding, uses a slightly different welding torch to create a more focused welding arc and as a result is often automated.\nDevelopment.\nAfter the discovery of the short pulsed electric arc in 1801 by Humphry Davy and of the continuous electric arc in 1802 by Vasily Petrov, arc welding developed slowly. C. L. Coffin had the idea of welding in an inert gas atmosphere in 1890, but even in the early 20th century, welding non-ferrous materials such as aluminum and magnesium remained difficult because these metals react rapidly with the air, resulting in porous, dross-filled welds. Processes using flux-covered electrodes did not satisfactorily protect the weld area from contamination. To solve the problem, bottled inert gases were used in the beginning of the 1930s. A few years later, a direct current, gas-shielded welding process emerged in the aircraft industry for welding magnesium.\nIn early 1940s Northrop Aircraft was developing an experimental aircraft from magnesium designated XP-56, for which Vladimir Pavlecka, Tom Piper and Russell Meredith developed a welding process named Heliarc because it used a tungsten electrode arc and helium as a shielding gas (the torch design was patented by Meredith in 1941). It is now often referred to as tungsten inert gas welding (TIG), especially in Europe, but the American Welding Society's official term is gas tungsten arc welding (GTAW). Linde Air Products developed a wide range of air-cooled and water-cooled torches, gas lenses to improve shielding, and other accessories that increased the use of the process. Initially, the electrode overheated quickly and, despite tungsten's high melting temperature, particles of tungsten were transferred to the weld. To address this problem, the polarity of the electrode was changed from positive to negative, but the change made it unsuitable for welding many non-ferrous materials. Finally, the development of alternating current units made it possible to stabilize the arc and produce high quality aluminum and magnesium welds.\nDevelopments continued during the following decades. Linde developed water-cooled torches that helped prevent overheating when welding with high currents. During the 1950s, as the process continued to gain popularity, some users turned to carbon dioxide as an alternative to the more expensive welding atmospheres consisting of argon and helium, but this proved unacceptable for welding aluminum and magnesium because it reduced weld quality, so it is rarely used with GTAW today. The use of any shielding gas containing an oxygen compound, such as carbon dioxide, quickly contaminates the tungsten electrode, making it unsuitable for the TIG process.\nIn 1953, a new process based on GTAW was developed, called plasma arc welding. It affords greater control and improves weld quality by using a nozzle to focus the electric arc, but is largely limited to automated systems, whereas GTAW remains primarily a manual, hand-held method. Development within the GTAW process has continued as well, and today a number of variations exist. Among the most popular are the pulsed-current, manual programmed, hot-wire, dabber, and increased penetration GTAW methods.\nOperation.\nManual gas tungsten arc welding is a relatively difficult welding method, due to the coordination required by the welder. Similar to torch welding, GTAW normally requires two hands, since most applications require that the welder manually feed a filler metal into the weld area with one hand while manipulating the welding torch in the other. Maintaining a short arc length, while preventing contact between the electrode and the workpiece, is also important.\nTo strike the welding arc, a high-frequency generator (similar to a Tesla coil) provides an electric spark. This spark is a conductive path for the welding current through the shielding gas and allows the arc to be initiated while the electrode and the workpiece are separated, typically about apart. \nOnce the arc is struck, the welder moves the torch in a small circle to create a welding pool, the size of which depends on the size of the electrode and the amount of current. While maintaining a constant separation between the electrode and the workpiece, the operator then moves the torch back slightly and tilts it backward about 10–15 degrees from vertical. Filler metal is added manually to the front end of the weld pool as it is needed.\nWelders often develop a technique of rapidly alternating between moving the torch forward (to advance the weld pool) and adding filler metal. The filler rod is withdrawn from the weld pool each time the electrode advances, but it is always kept inside the gas shield to prevent oxidation of its surface and contamination of the weld. Filler rods composed of metals with a low melting temperature, such as aluminum, require that the operator maintain some distance from the arc while staying inside the gas shield. If held too close to the arc, the filler rod can melt before it makes contact with the weld puddle. As the weld nears completion, the arc current is often gradually reduced to allow the weld crater to solidify and prevent the formation of crater cracks at the end of the weld.\nThe physics of GTAW involves several complex processes, including thermodynamics, plasma physics, and fluid dynamics. The non-consumable tungsten electrode can be operated as a Cathode or Anode and is used to produce an electric arc between the electrode and the workpiece. In order to initially create the arc, the welding area is flooded with inert gas and a high strike voltage (typically 1 kV per 1 mm) is generated by the welding machine to overcome the electric resistivity of the atmosphere surrounding the welding area. With the arc established, the voltage is lowered and current flows between the work piece and electrode. Despite the high temperatures of this electric arc, the main heat transfer mechanism in GTAW is the joule heating resulting from this current flow. \nSafety.\nWelders wear protective clothing, including light and thin leather gloves and protective long sleeve shirts with high collars, to avoid exposure to strong ultraviolet light. Due to the absence of smoke in GTAW, the electric arc light is not covered by fumes and particulate matter as in stick welding or shielded metal arc welding, and thus is a great deal brighter, subjecting operators to strong ultraviolet light. The welding arc has a different range and strength of UV light wavelengths from sunlight, but the welder is very close to the source and the light intensity is very strong. Potential arc light damage includes accidental flashes to the eye or arc eye and skin damage similar to strong sunburn. Operators wear opaque helmets with dark eye lenses and full head and neck coverage to prevent this exposure to UV light. Modern helmets often feature a liquid crystal-type face plate that self-darkens upon exposure to the bright light of the struck arc. Transparent welding curtains, made of a strongly colored polyvinyl chloride plastic film, are often used to shield nearby workers and bystanders from exposure to the UV light from the electric arc.\nWelders are also often exposed to dangerous gases and particulate matter. While the process doesn't produce smoke, the brightness of the arc in GTAW can break down surrounding air to form ozone and nitric oxides. The ozone and nitric oxides react with lung tissue and moisture to create nitric acid and ozone burn. Ozone and nitric oxide levels are moderate, but exposure duration, repeated exposure, and the quality and quantity of fume extraction, and air change in the room must be monitored. Welders who do not work safely can contract emphysema and oedema of the lungs, which can lead to early death. Similarly, the heat from the arc can cause poisonous fumes to form from cleaning and degreasing materials. Cleaning operations using these agents should not be performed near the site of welding, and proper ventilation is necessary to protect the welder.\nApplications.\nWhile the aerospace industry is one of the primary users of gas tungsten arc welding, the process is used in a number of other areas. Many industries use GTAW for welding thin workpieces, especially nonferrous metals. It is used extensively in the manufacture of space vehicles and is also frequently employed to weld small-diameter, thin-wall tubing such as that used in the bicycle industry. In addition, GTAW is often used to make root or first-pass welds for piping of various sizes. In maintenance and repair work, the process is commonly used to repair tools and dies, especially components made of aluminum and magnesium. Because the weld metal is not transferred directly across the electric arc like most open arc welding processes, a vast assortment of welding filler metal is available to the welding engineer. In fact, no other welding process permits the welding of so many alloys in so many product configurations. Filler metal alloys, such as elemental aluminum and chromium, can be lost through the electric arc from volatilization. This loss does not occur with the GTAW process. Because the resulting welds have the same chemical integrity as the original base metal or match the base metals more closely, GTAW welds are highly resistant to corrosion and cracking over long time periods, making GTAW the welding procedure of choice for critical operations like sealing spent nuclear fuel canisters before burial.\nQuality.\nGas tungsten arc welding, because it affords greater control over the weld area than other welding processes, can produce high-quality welds when performed by skilled operators. Maximum weld quality is assured by maintaining cleanliness—all equipment and materials used must be free from oil, moisture, dirt and other impurities, as these cause weld porosity and consequently a decrease in weld strength and quality. To remove oil and grease, alcohol or similar commercial solvents may be used, while a stainless steel wire brush or chemical process can remove oxides from the surfaces of metals like aluminum. Rust on steels can be removed by first grit blasting the surface and then using a wire brush to remove any embedded grit. These steps are especially important when negative polarity direct current is used, because such a power supply provides no cleaning during the welding process, unlike positive polarity direct current or alternating current. To maintain a clean weld pool during welding, the shielding gas flow should be sufficient and consistent so that the gas covers the weld and blocks impurities in the atmosphere. GTAW in windy or drafty environments increases the amount of shielding gas necessary to protect the weld, increasing the cost and making the process unpopular outdoors.\nThe level of heat input also affects weld quality. Low heat input, caused by low welding current or high welding speed, can limit penetration and cause the weld bead to lift away from the surface being welded. If there is too much heat input, however, the weld bead grows in width while the likelihood of excessive penetration and spatter (emission of small, unwanted droplets of molten metal) increases. Additionally, if the welding torch is too far from the workpiece the shielding gas becomes ineffective, causing porosity within the weld. This results in a weld with pinholes, which is weaker than a typical weld.\nIf the amount of current used exceeds the capability of the electrode, tungsten inclusions in the weld may result. Known as tungsten spitting, this can be identified with radiography and can be prevented by changing the type of electrode or increasing the electrode diameter. In addition, if the electrode is not well protected by the gas shield or the operator accidentally allows it to contact the molten metal, it can become dirty or contaminated. This often causes the welding arc to become unstable, requiring that the electrode be ground with a diamond abrasive to remove the impurity.\nEquipment.\nThe equipment required for the gas tungsten arc welding operation includes a welding torch utilizing a non-consumable tungsten electrode, a constant-current welding power supply, and a shielding gas source.\nWelding torch.\nGTAW welding torches are designed for either automatic or manual operation and are equipped with cooling systems using air or water. The automatic and manual torches are similar in construction, but the manual torch has a handle while the automatic torch normally comes with a mounting rack. The angle between the centerline of the handle and the centerline of the tungsten electrode, known as the head angle, can be varied on some manual torches according to the preference of the operator. Air cooling systems are most often used for low-current operations (up to about 200 A), while water cooling is required for high-current welding (up to about 600 A). The torches are connected with cables to the power supply and with hoses to the shielding gas source and where used, the water supply.\nThe internal metal parts of a torch are made of hard alloys of copper or brass so it can transmit current and heat effectively. The tungsten electrode must be held firmly in the center of the torch with an appropriately sized collet, and ports around the electrode provide a constant flow of shielding gas. Collets are sized according to the diameter of the tungsten electrode they hold. The body of the torch is made of heat-resistant, insulating plastics covering the metal components, providing insulation from heat and electricity to protect the welder.\nThe size of the welding torch nozzle depends on the amount of shielded area desired. The size of the gas nozzle depends upon the diameter of the electrode, the joint configuration, and the availability of access to the joint by the welder. The inside diameter of the nozzle is preferably at least three times the diameter of the electrode, but there are no hard rules. The welder judges the effectiveness of the shielding and increases the nozzle size to increase the area protected by the external gas shield as needed. The nozzle must be heat resistant and thus is normally made of alumina or a ceramic material, but fused quartz, a high purity glass, offers greater visibility. Devices can be inserted into the nozzle for special applications, such as gas lenses or valves to improve the control shielding gas flow to reduce turbulence and the introduction of contaminated atmosphere into the shielded area. Hand switches to control welding current can be added to the manual GTAW torches.\nPower supply.\nGas tungsten arc welding uses a constant current power source, meaning that the current (and thus the heat flux) remains relatively constant, even if the arc distance and voltage change. This is important because most applications of GTAW are manual or semiautomatic, requiring that an operator hold the torch. Maintaining a suitably steady arc distance is difficult if a constant voltage power source is used instead since it can cause dramatic heat variations and make welding more difficult.\nThe preferred polarity of the GTAW system depends largely on the type of metal being welded. Direct current with a negatively charged electrode (DCEN) is often employed when welding steels, nickel, titanium, and other metals. It can also be used in automatic GTAW of aluminum or magnesium when helium is used as a shielding gas. The negatively charged electrode generates heat by emitting electrons, which travel across the arc, causing thermal ionization of the shielding gas and increasing the temperature of the base material. The ionized shielding gas flows toward the electrode, not the base material, and this can allow oxides to build on the surface of the weld. Direct current with a positively charged electrode (DCEP) is less common, and is used primarily for shallow welds since less heat is generated in the base material. Instead of flowing from the electrode to the base material, as in DCEN, electrons go the other direction, causing the electrode to reach very high temperatures. To help it maintain its shape and prevent softening, a larger electrode is often used. As the electrons flow toward the electrode, ionized shielding gas flows back toward the base material, cleaning the weld by removing oxides and other impurities and thereby improving its quality and appearance.\nAlternating current, commonly used when welding aluminum and magnesium manually or semi-automatically, combines the two direct currents by making the electrode and base material alternate between positive and negative charge. This causes the electron flow to switch directions constantly, preventing the tungsten electrode from overheating while maintaining the heat in the base material. Surface oxides are still removed during the electrode-positive portion of the cycle and the base metal is heated more deeply during the electrode-negative portion of the cycle. Some power supplies enable operators to use an unbalanced alternating current wave by modifying the exact percentage of time that the current spends in each state of polarity, giving them more control over the amount of heat and cleaning action supplied by the power source. In addition, operators must be wary of rectification, in which the arc fails to reignite as it passes from straight polarity (negative electrode) to reverse polarity (positive electrode). To remedy the problem, a square wave power supply can be used, as can high-frequency to encourage arc stability.\nElectrode.\nThe electrode used in GTAW is made of tungsten or a tungsten alloy, because tungsten has the highest melting temperature among pure metals, at . As a result, the electrode is not consumed during welding, though some erosion (called burn-off) can occur. Electrodes can have either a clean finish or a ground finish—clean finish electrodes have been chemically cleaned, while ground finish electrodes have been ground to a uniform size and have a polished surface, making them optimal for heat conduction. The diameter of the electrode can vary between , and their length can range from .\nA number of tungsten alloys have been standardized by the International Organization for Standardization and the American Welding Society in ISO 6848 and AWS A5.12, respectively, for use in GTAW electrodes, and are summarized in the adjacent table.\nFiller metals are also used in nearly all applications of GTAW, the major exception being the welding of thin materials. Filler metals are available with different diameters and are made of a variety of materials. In most cases, the filler metal in the form of a rod is added to the weld pool manually, but some applications call for an automatically fed filler metal, which often is stored on spools or coils.\nShielding gas.\nAs with other welding processes such as gas metal arc welding, shielding gases are necessary in GTAW to protect the welding area from atmospheric gases such as nitrogen and oxygen, which can cause fusion defects, porosity, and weld metal embrittlement if they come in contact with the electrode, the arc, or the welding metal. The gas also transfers heat from the tungsten electrode to the metal, and it helps start and maintain a stable arc.\nThe selection of a shielding gas depends on several factors, including the type of material being welded, joint design, and desired final weld appearance. Argon is the most commonly used shielding gas for GTAW, since it helps prevent defects due to a varying arc length. When used with alternating current, argon shielding results in high weld quality and good appearance. Another common shielding gas, helium, is most often used to increase the weld penetration in a joint, to increase the welding speed, and to weld metals with high heat conductivity, such as copper and aluminum. A significant disadvantage is the difficulty of striking an arc with helium gas, and the decreased weld quality associated with a varying arc length.\nArgon-helium mixtures are also frequently utilized in GTAW, since they can increase control of the heat input while maintaining the benefits of using argon. Normally, the mixtures are made with primarily helium (often about 75% or higher) and a balance of argon. These mixtures increase the speed and quality of the AC welding of aluminum, and also make it easier to strike an arc. Another shielding gas mixture, argon-hydrogen, is used in the mechanized welding of light gauge stainless steel, but because hydrogen can cause porosity, its uses are limited. Similarly, nitrogen can sometimes be added to argon to help stabilize the austenite in austenitic stainless steels and increase penetration when welding copper. Due to porosity problems in ferritic steels and limited benefits, however, it is not a popular shielding gas additive.\nMaterials.\nGas Tungsten Arc Welding is most commonly used to weld stainless steel and nonferrous materials, such as aluminum and magnesium, but it can be applied to nearly all metals, with a notable exception being zinc and its alloys. Its applications involving carbon steels are limited not because of process restrictions, but because of the existence of more economical steel welding techniques, such as gas metal arc welding and shielded metal arc welding. Furthermore, GTAW can be performed in a variety of other-than-flat positions, depending on the skill of the welder and the materials being welded.\nAluminum and magnesium.\nAluminum and magnesium are most often welded using alternating current, but the use of direct current is also possible, depending on the properties desired. Before welding, the work area should be cleaned and may be preheated to for aluminum or to a maximum of for thick magnesium workpieces to improve penetration and increase travel speed. Alternating current can provide a self-cleaning effect, removing the thin, refractory aluminum oxide layer that forms on aluminum metal within minutes of exposure to air. This oxide layer must be removed for welding to occur. When alternating current is used, pure tungsten electrodes or zirconiated tungsten electrodes are preferred over thoriated electrodes, as the latter are more likely to \"spit\" electrode particles across the welding arc into the weld. Blunt electrode tips are preferred, and pure argon shielding gas should be employed for thin workpieces. Introducing helium allows for greater penetration in thicker workpieces, but can make arc starting difficult.\nDirect current of either polarity, positive or negative, can be used to weld aluminum and magnesium as well. Direct current with a negatively charged electrode (DCEN) allows for high penetration. Argon is commonly used as a shielding gas for DCEN welding of aluminum. Shielding gases with high helium contents are often used for higher penetration in thicker materials. Thoriated electrodes are suitable for use in DCEN welding of aluminum. Direct current with a positively charged electrode (DCEP) is used primarily for shallow welds, especially those with a joint thickness of less than . A thoriated tungsten electrode is commonly used, along with pure argon shielding gas.\nSteels.\nFor GTAW of carbon and stainless steels, the selection of filler material is important to prevent excessive porosity. Oxides on the filler material and workpieces must be removed before welding to prevent contamination, and immediately prior to welding, alcohol or acetone should be used to clean the surface. Preheating is generally not necessary for mild steels less than one inch thick, but low alloy steels may require preheating to slow the cooling process and prevent the formation of martensite in the heat-affected zone. Tool steels should also be preheated to prevent cracking in the heat-affected zone. Austenitic stainless steels do not require preheating, but martensitic and ferritic chromium stainless steels do. A DCEN power source is normally used, and thoriated electrodes, tapered to a sharp point, are recommended. Pure argon is used for thin workpieces, but helium can be introduced as thickness increases.\nDissimilar metals.\nWelding dissimilar metals often introduce new difficulties to GTAW welding, because most materials do not easily fuse to form a strong bond. However, welds of dissimilar materials have numerous applications in manufacturing, repair work, and the prevention of corrosion and oxidation. In some joints, a compatible filler metal is chosen to help form the bond, and this filler metal can be the same as one of the base materials (for example, using a stainless steel filler metal with stainless steel and carbon steel as base materials), or a different metal (such as the use of a nickel filler metal for joining steel and cast iron). Very different materials may be coated or \"buttered\" with a material compatible with particular filler metal, and then welded. In addition, GTAW can be used in cladding or overlaying dissimilar materials.\nWhen welding dissimilar metals, the joint must have an accurate fit, with proper gap dimensions and bevel angles. Care should be taken to avoid melting excessive base material. Pulsed current is particularly useful for these applications, as it helps limit the heat input. The filler metal should be added quickly, and a large weld pool should be avoided to prevent dilution of the base materials.\nProcess variations.\nPulsed-current.\nIn the pulsed-current mode, the welding current rapidly alternates between two levels. The higher current state is known as the pulse current, while the lower current level is called the background current. During the period of pulse current, the weld area is heated and fusion occurs. Upon dropping to the background current, the weld area is allowed to cool and solidify. Pulsed-current GTAW has a number of advantages, including lower heat input and consequently a reduction in distortion and warpage in thin workpieces. In addition, it allows for greater control of the weld pool, and can increase weld penetration, welding speed, and quality. A similar method, manual programmed GTAW, allows the operator to program a specific rate and magnitude of current variations, making it useful for specialized applications.\nDabber.\nThe dabber variation is used to precisely place weld metal on thin edges. The automatic process replicates the motions of manual welding by feeding a cold or hot filler wire into the weld area and dabbing (or oscillating) it into the welding arc. It can be used in conjunction with pulsed current, and is used to weld a variety of alloys, including titanium, nickel, and tool steels. Common applications include rebuilding seals in jet engines and building up saw blades, milling cutters, drill bits, and mower blades.", "Engineering,_Manufacturing": 0.9999904633, "qwen": "Yes"}
{"id": "1449329", "revid": "102362", "url": "https://en.wikipedia.org/wiki?curid=1449329", "title": "Plasma arc welding", "text": "Plasma arc welding (PAW) is an arc welding process similar to gas tungsten arc welding (GTAW). The electric arc is formed between an electrode (which is usually but not always made of sintered tungsten) and the workpiece. The key difference from GTAW is that in PAW, the electrode is positioned within the body of the torch, so the plasma arc is separated from the shielding gas envelope. The plasma is then forced through a fine-bore copper nozzle which constricts the arc and the plasma exits the orifice at high velocities (approaching the speed of sound) and a temperature approaching 28,000 °C (50,000 °F) or higher.\nArc plasma is a temporary state of a gas. The gas gets ionized by electric current passing through it and it becomes a conductor of electricity. In ionized state, atoms are broken into electrons (−) and cations (+) and the system contains a mixture of ions, electrons and highly excited atoms. The degree of ionization may be between 1% and greater than 100% (possible with double and triple degrees of ionization). Such states exist as more electrons are pulled from their orbits.\nThe energy of the plasma jet and thus the temperature depends upon the electrical power employed to create arc plasma. A typical value of temperature obtained in a plasma jet torch is on the order of ), compared to about ) in ordinary electric welding arc. All welding arcs are (partially ionized) plasmas, but the one in plasma arc welding is a constricted arc plasma.\nJust as oxy-fuel torches can be used for either welding or cutting, so too can plasma torches.\nConcept.\nPlasma arc welding is an arc welding process wherein coalescence is produced by the heat obtained from a constricted arc setup between a tungsten/alloy tungsten electrode and the water-cooled (constricting) nozzle (non-transferred arc) or between a tungsten/alloy tungsten electrode and the job (transferred arc). The process employs two inert gases, one forms the arc plasma and the second shields the arc plasma. Filler metal may or may not be added.\nHistory.\nThe plasma arc welding and cutting process was invented by Robert M. Gage in 1953 and patented in 1957. The process was unique in that it could achieve precision cutting and welding on both thin and thick metals. It was also capable of spray coating hardening metals onto other metals. One example was the spray coating of the turbine blades of the moon bound Saturn rocket.\nPrinciple of operation.\nPlasma arc welding is an advanced form of tungsten inert gas (TIG) welding. In the case of TIG, it is an open arc shielded by argon or helium, whereas plasma uses a special torch where the nozzle is used to constrict the arc while the shielding gas is separately supplied by the torch. The arc is constricted with the help of a water-cooled small diameter nozzle which squeezes the arc, increases its pressure, temperature and heat intensely and thus improves arc stability, arc shape and heat transfer characteristics.\nPlasma arcs are formed using gas in two forms; laminar (low pressure and low flow) and turbulent (high pressure and high flow).\nThe gases used are argon, helium, hydrogen or a mixture of these. In the case of plasma welding, laminar flow (low pressure and low flow of plasma gas) is employed to ensure that the molten metal is not blown out of the weld zone.\nThe non-transferred arc (pilot arc) is employed during plasma-welding to initiate the welding process. The arc is formed between the electrode(-) and the water-cooled constricting nozzle (+). A non-transferred arc is initiated by using a high-frequency unit in the circuit. After the initial high-frequency start, the pilot arc (low current) is formed between the elect by employing a low current. After the main arc is struck, the nozzle is neutral or in case of welding-mesh using micro plasma, there can be an option given to have a continuous pilot arc. A transferred arc possesses high energy density and plasma jet velocity. Depending on the current used and flow of gas, it can be employed to cut and melt metals.\nMicroplasma uses current between 0.1 and 10 amps and is used foils, bellow, and thin sheets. This is an autogenous process and normally does not use filler wire or powder.\nMedium plasma uses current between 10 and 100 amps and is used for higher-thickness plate welding with filler wire or autogenous up to plates and metal deposition (hardfacing) using specialised torches and powder feeders (PTA) using metal powders.\nHigh-current plasma above 100 amps is used with filler wires welding at high travel speeds.\nOther applications of plasma are plasma-cutting, heating, deposition of diamond films (Kurihara et al. 1989), material processing, metallurgy (production of metals and ceramics), plasma-spraying, and underwater cutting.\nEquipment.\nThe equipment needed in plasma arc welding along with their functions are as follows:\nTypical welding parameters for plasma arc welding are as follows:\nCurrent 50 to 350 amps, voltage 27 to 31 volts, gas flow rates 2 to 40 liters/minute (lower range for orifice gas and higher range for outer shielding gas), direct current electrode negative (DCEN) is normally employed for plasma arc welding except for the welding of aluminum in which cases water-cooled electrode is preferable for reverse-polarity welding, i.e. direct-current electrode positive (DCEP).\nFor cutting purposes, a mixture of argon and hydrogen (10-30%) or that of nitrogen may be used. Hydrogen, because of its dissociation into atomic form and thereafter recombination generates temperatures above those attained by using argon or helium alone. In addition, hydrogen provides a reducing atmosphere, which helps in preventing oxidation of the weld and its vicinity. Care must be taken, as hydrogen diffusing into the metal can lead to embrittlement in some metals and steels.\nProcess description.\nThe technique of work-piece cleaning and filler-metal addition is similar to that in TIG welding. Filler metal is added at the leading edge of the weld pool. Filler metal is not required in making root-pass weld.\nType of Joints: For welding work piece up to 25 mm thick, joints like square butt, J or V are employed. Plasma welding is used to make both key hole and non-key hole types of welds.\nMaking a non-key-hole weld: The process can make non-key-hole welds on work pieces having thickness 2.4 mm and under.\nMaking a keyhole welds: An outstanding characteristic of plasma arc welding, owing to exceptional penetrating power of plasma jet, is its ability to produce keyhole welds in work piece having thickness from 2.5 mm to 25 mm. A keyhole effect is achieved through right selection of current, nozzle-orifice diameter and travel speed, which create a forceful plasma jet to penetrate completely through the work piece. Plasma jet in no case should expel the molten metal from the joint. The major advantages of the keyhole technique are the ability to penetrate rapidly through relatively thick root sections and to produces a uniform under bead without mechanical backing. Also, the ratio of the depth of penetration to the width of the weld is much higher, resulting narrower weld and heat-affected zone. As the weld progresses, base metal ahead the keyhole melts, flow around the same solidifies and forms the weld bead. Key-holing aids deep penetration at faster speeds and produces high-quality bead. While welding thicker pieces, in laying others than root run, and using filler metal, the force of plasma jet is reduced by suitably controlling the amount of orifice gas.\nPlasma arc welding is an advancement over the GTAW process. This process uses a non-consumable tungsten electrode and an arc constricted through a fine-bore copper nozzle. PAW can be used to join all metals that are weldable with GTAW (i.e., most commercial metals and alloys). Difficult-to-weld in metals by PAW include bronze, cast iron, lead and magnesium.\nSeveral basic PAW process variations are possible by varying the current, plasma gas-flow rate, and the orifice diameter, including:\nProcess variables.\nGases.\nAt least two separate (and possibly three) flows of gas are used in PAW:\nThese gases can all be same, or of differing composition.\nOther plasma arc processes.\nDepending upon the design of the torch (e.g., orifice diameter), electrode design, gas type and velocities, and the current levels, several variations of the plasma process are achievable, including:\nPlasma arc cutting.\nWhen used for cutting, the plasma gas flow is increased so that the deeply penetrating plasma jet cuts through the material and molten material is removed as cutting dross. PAC differs from oxy-fuel cutting in that the plasma process operates by using the arc to melt the metal whereas in the oxy-fuel process, the oxygen oxidizes the metal and the heat from the exothermic reaction melts the metal. Unlike oxy-fuel cutting, the PAC process can be applied to cutting metals which form refractory oxides such as stainless steel, cast iron, aluminum and other non-ferrous alloys. Since PAC was introduced by Praxair Inc. at the American Welding Society show in 1954, many process refinements, gas developments, and equipment improvements have occurred.\nExternal links.\nPlasma Arc Welding\nMicroplasma welding\nArc spray welding", "Engineering,_Manufacturing": 1.0000085831, "qwen": "Yes"}
{"id": "61258425", "revid": "5346607", "url": "https://en.wikipedia.org/wiki?curid=61258425", "title": "Roll trailer", "text": "A roll trailer is a trailer platform that requires towing by a powered vehicle. It is commonly used for the transport of heavy static goods and materials in the maritime shipping industry. Roll trailers are similar to shipping containers, however, they have a set of rear wheels. \nOverview.\nRoll trailers are a common equipment used in ports and on board of roll-on/roll-off ships, to facilitate the shipping of unmovable commodities and oversize load from one port to another.\nStandard lengths of roll trailers are , in line with twenty-foot equivalent unit shipping containers, but can also be found in lengths of . The standard payloads of roll trailers vary from 40 to 120 tons, and the tare of the trailer varies from 7 to 10 tons.\nThe trailer has a steel structure and a hardwood surface, plus a front pocket for towing by tugmaster gooseneck, and side handles for applying lashing hooks.\nOperations.\nGoods are usually placed on roll trailers by forklift or shore crane, secured with lashing or chains, and then towed on/off board via tugmaster tractor. When empty, they can be stacked like shipping containers.\nEvery trailer has a unique identification number stamped on sides, composed of four letters and seven digits, directly related to the manufacturer company abbreviation name, the payload capacity and its length size.\nAll the main shipping lines have an owned fleet of roll trailers available to be offered to shippers for moving heavy static cargo.\nAdditionally, all main roll trailers manufacturers tend to lease extra equipment during peak times, by charging a daily hire fee to the shipping lines.\nOnce in the port, after a short \"free time\" period, roll trailers are subject to demurrage charges, to cover storage and detention fees and to ensure consignees swiftly unload their cargo, temporary positioned on the shipping line's trailers during the sea passage.\nAs per standard practice, and opposite to shipping containers, roll trailers are not permitted to exit the ports, with receivers requested to collect their goods inside the terminals.", "Engineering,_Manufacturing": 0.9975374341, "qwen": "Yes"}
{"id": "61287985", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=61287985", "title": "Assembly line feeding problem", "text": "The assembly line feeding problem (abbr. ALFP) describes a problem in operations management concerned with finding the optimal way of feeding parts to assembly stations. For this, various cost elements may be taken into account and every part is assigned to a policy, i.e., a way of feeding parts to an assembly line. The most common policies are:\nThese policies differ with respect to the way parts are brought to the line as well as in the way parts are handled before they are brought to the line. E.g., in line stocking, parts are brought to the line directly in the way they are stored in the warehouse. In the other policies, quantities are reduced (boxed supply) and different part variants are sorted in the order of demand (sequencing, stationary, and traveling kitting).\nHistory.\nThe problem was formally introduced by Bozer and McGinnis in 1992 by means of a descriptive cost model. Since then, many contributions have been made in both, quantitative and qualitative manners. E.g., a more qualitative contribution is done by Hua and Johnson investigating important aspects of the problem, whereas more recent contributions focus rather on quantitative aspects and use mathematical optimization to solve this assignment problem to optimality \nMathematical problem statement.\nformula_1\nThis model minimizes the costs formula_2 when assigning all parts (index:i) to a feeding policy (index:p) at all stations (index:s) formula_3, if there is a demand for a part at a station formula_4. Using a certain policy at a station formula_5 incurs some cost formula_6 as well as some other costs formula_7 are incurred when a policy is used at any station formula_8.\nAll assembly line feeding problems of this type have been proven to be NP-hard", "Engineering,_Manufacturing": 0.9886336327, "qwen": "Yes"}
{"id": "43569366", "revid": "1165188717", "url": "https://en.wikipedia.org/wiki?curid=43569366", "title": "Camelot Management Consultants AG", "text": "Camelot Management Consultants AG is an international consulting firm with focus on Supply Chain Management. 320 consultants work directly for Camelot Management Consultants and around 1.400 consultants work in Camelot's partner organizations in eight branch offices. CEO of Camelot Management Consultants was Josef Packowski.\nServices.\nCamelot Management Consultants is specialized in Value Chain Management in the core industries Chemicals & Petrochemicals, Pharmaceuticals & Life Sciences and Consumer Goods. The company combines management consulting and implementation in the areas of (excerpt): Supply Chain Management, Finance & Performance Management, Sourcing & Procurement, Logistics & Distribution, Master Data Management, Transport Management and Strategic Information Management.\nLEAN Supply Chain Planning.\nCamelot Management Consultants has developed a Supply Chain Management approach LEAN Supply Chain Planning. T\nAwards.\nCamelot Management Consultants has received several awards in the last years. In 2012 the management consultancy received an award in the category “Supply Chain Management” in the competition “Best of Consulting” run by the German business magazine \"Wirtschaftswoche\", in 2013 the technology partner Camelot ITLab was honored for the best “IT Management” in the competition. In 2014 Camelot Management Consultants also received the award by \"brandeins\" in the competition “Beste Berater 2014 (Best Consultants 2014)”. In 2013, Camelot Management Consultants was awarded as “Top Consultant” for being one of the best mid-sized consulting firm. The Hochschule Bonn-Rhein-Sieg awarded the unit Camelot ITLab 2014 with the certificate “Top-Consultant” for one of the best IT consultancy firms. In 2014 Camelot ITLab also received the “INNOVATIONSPREIS-IT” in the category “Best of ERP 2014”.", "Engineering,_Manufacturing": 0.9963094592, "qwen": "Yes"}
{"id": "234730", "revid": "1143735934", "url": "https://en.wikipedia.org/wiki?curid=234730", "title": "MacPherson strut", "text": "The MacPherson strut is a type of automotive suspension system that uses the top of a telescopic damper as the upper steering pivot. It is widely used in the front suspension of modern vehicles. The name comes from American automotive engineer Earle S. MacPherson, who invented and developed the design.\nHistory.\nEarle S. MacPherson was appointed the chief engineer of Chevrolet's Light Car project in 1945. He was tasked with developing a new, smaller car for the immediate post-war market, an effort that led to the Chevrolet Cadet.\nThe Cadet was poised to be a groundbreaking vehicle, and the three prototypes that had been built by 1946 displayed a wide range of innovations. One of these was a revolutionary new independent suspension system that featured what is now known as a MacPherson strut. The Cadet was slated to be the first production vehicle with MacPherson struts, but the project was cancelled in 1947 and never saw commercial production. This was in large part due to GM's concerns about the Cadet's forecasted profit margins. \nAfter the Cadet project was shelved, a disgruntled MacPherson left GM to join Ford. Patents were filed in 1947 ( for GM) and in 1949 ( for Ford), with the latter patent citing designs by Guido Fornaca of FIAT in the mid-1920s. \nMacPherson's new strut design may have taken inspirations from other earlier designs as well. The strut suspension of the pre-war Stout Scarab could have been an influence, and long-travel struts in aircraft landing gear were well known by that time. The French Cottin-Desgouttes utilized a similar design, albeit with less sophisticated leaf springs, but the Cottin-Desgouttes front suspension was in turn inspired by a 1904 design by American engineer J. Walter Christie.\nMacPherson designed the strut for all four wheels, but it is normally used for the front suspension only, where it provides a steering pivot as well as a suspension mounting for the wheel.\nThe first production car to use MacPherson struts is often cited incorrectly as the French 1949 Ford Vedette, but it was developed before MacPherson, with an independent front suspension based on wishbones and an upper coil spring. Only in 1954, after the Vedette factory had been purchased by Simca, did the revised Simca Vedette switch to using front struts.\nFollowing MacPherson's arrival at Ford, the first production car to feature MacPherson struts was the British-built 1950 Ford Consul and the later Zephyr.\nDesign.\nA MacPherson strut uses a wishbone, or a substantial compression link stabilized by a secondary link, which provides a mounting point for the hub carrier or axle of the wheel. The lower arm system provides both lateral and longitudinal location of the wheel. The upper part of the hub carrier is rigidly fixed to the bottom of the outer part of the strut proper. That slides up and down the inner part of it, which extends upwards directly to a mounting in the body shell of the vehicle. The line from the top mount of the strut to the bottom ball joint on the control arm gives the steering axis inclination. The axis of the strut may be angled inwards from the steering axis at the bottom, to clear the tyre, which makes the bottom follow an arc when steering.\nThe MacPherson strut benefited from introduction of unitary construction, because its design requires substantial vertical space and a strong top mount, which unibody construction can provide. Unibody construction also distributes suspension stresses. The strut will usually carry both the coil spring, on which the body is suspended, and the shock absorber, which is usually in the form of a cartridge mounted within the strut (see coilover). The strut can also have the steering arm built into the lower outer portion. The whole assembly is very simple and can be pre-assembled into a unit. As well, the elimination of the upper control arm allows for more width in the engine compartment, which is useful for smaller cars, particularly with transverse-mounted engines, such as most front wheel drive vehicles have. The assembly can be further simplified, if needed, by substituting an anti-roll bar (torsion bar) for the radius arm. For those reasons, it has become almost ubiquitous with low cost manufacturers. Furthermore, it offers an easy method to set suspension geometry.\nMany modern versions replace the lower control arm with a wishbone. An anti-roll bar is optional and, if present, is attached by a ball-jointed rod to the spring-damper, or by a ball or elastomerically jointed rod to the wishbone.\nAdvantages and disadvantages.\nBecause MacPherson struts are packaged with a significant structure in the front crash structure of the car, it is easier to engineer cars that pass more stringent small overlap crashes with struts, as opposed to those with a double wishbone suspension. Notable examples include the Honda Accord and Civic, as well as the Mercedes E-Class, all of which adopted struts to improve crash performance. The overall simplicity of the design also means there are fewer joints in the suspension to wear, so there is less decline in handling and steering feel over time. Inverted monotube struts can also provide extra rigidity in the front suspension, as seen in the Porsche 911 GT3 and Cayman GT4, as well as the Subaru Impreza WRX STI. Finally, struts can package more efficiently than other types of front suspension, which allows for significant front cargo space in rear/mid-engined cars, such as the Porsche 911 and Boxster.\nGeometric analysis shows the assembly cannot allow vertical movement of the wheel without some degree of either camber angle change, sideways movement, or both. It is not generally considered to give as good handling as a double wishbone or multi-link suspension, because it allows the engineers less freedom to choose camber change and roll center. Cars that have cockpit adjustable ride height generally cannot have MacPherson struts because of the camber changes that are an unavoidable part of the design. Ride suffers because the shock absorber has almost the same vertical motion as the wheel, so there is relatively little leverage to break the stiction in the seals. A standard single pivot MacPherson strut also tends to have positive scrub where the center of the steering axis is offset from the center of the front tires, which results in torque steer.\nDespite the drawbacks, the MacPherson strut set-up is still used on some high performance cars, because they tend to have relatively small suspension travel, and so do not have the same kinematic problems.\nUp until the 1989 model year (964), Porsche 911 used a similar strut design that did not have coil springs, using torsion bar suspension instead. Since then, all Porsche 911s have had front MacPherson struts, except the 992-based 911 GT3, which uses a double wishbone.\nIn recent years, General Motors and Ford have introduced a modified strut set-up, \"Hi-Per Strut\" and \"Revoknuckle\" respectively, that split the strut into two components that handle the up-and-down flexibility and steering dynamics separately. The benefits of this design are greater surface contact and reduction in torque steer. The drawbacks are the additional weight and cost, but it is less expensive than either a double wishbone or multi-link setup. Honda introduced another variation strut set-up, called \"dual-axis\", which is used in the suspension design of the Civic Type-R. Another variant of the MacPherson strut is the double pivot front suspension, which splits the lower wishbone into two while retaining the standard upright design of the MacPherson strut. That allows for better control of steering geometry and scrub radius, while allowing for a larger brake assembly.", "Engineering,_Manufacturing": 0.9994128942, "qwen": "Yes"}
{"id": "39871498", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=39871498", "title": "Force chain", "text": "In the study of the physics of granular materials, a force chain consists of a set of particles within a compressed granular material that are held together and jammed into place by a network of mutual compressive forces.\nBetween these chains are regions of low stress whose grains are shielded for the effects of the grains above by vaulting and arching. A set of interconnected force chains is known as a force network. Force networks visualise inter-particle forces, which is particularly informative for spherical particle systems. For non-spherical particle systems force chain networks benefit from being supplemented by traction chain networks. Traction chains visualise inter-particle tractions, which give additional insight in inter-particle contact not captured by force chains, in particular, the role of contact area over which inter-particle forces act.\nForce networks are an emergent phenomenon that are created by the complex interaction of the individual grains of material and the patterns of pressure applied within the material. Force chains can be shown to have fractal properties.\nForce chains have been investigated both experimentally, through the construction of specially instrumented physical models, and through computer simulation.", "Engineering,_Manufacturing": 0.9999747276, "qwen": "Yes"}
{"id": "62408441", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=62408441", "title": "Metal swarf", "text": "Metal swarf, also known as chips or by other process-specific names (such as turnings, filings, or shavings), are pieces of metal that are the debris or waste resulting from machining or similar subtractive (material-removing) manufacturing processes. Metal swarf can be small particles (such as the gritty swarf from grinding metal) or long, stringy tendrils (such as the springy chips from turning tough metals).\nCutting hazards and safety precautions.\nCuts, splinters, punctures, airborne chips.\nChips can be extremely sharp, and this creates a safety problem, as they can cause serious injuries if not handled correctly. Depending on the composition of the material, it can persist in the environment for a long time before degrading. This, combined with the small size of some chips (e.g. those of brass or bronze), allows them to disperse widely by piggy-backing on soft materials and also to penetrate the skin as deep splinters.\nIt is standard training for machinists, and usually a standing workplace rule, to avoid handling swarf with bare hands. Similarly, it is also standard training for machinists, and usually a standing workplace rule, to minimize or entirely avoid handling swarf by blowing chips away with compressed air, but this practice can potentially damage the machine by causing chips to get jammed in and then embedded into the moving surfaces leading to degradation of the machine's precision. Alternatives to blowing chips away include vacuuming them away with an industrial vacuum (shop vacuum); gently washing them away with a coolant hose discharging at typical garden-hose pressures; or preventing their generation in the first place (for example, forming threads instead of cutting them). Some machine tool manuals proscribe these practices both for safety and for the preservation of way wipers and bearing seals.\nIt is not uncommon for chips flying off the cutter to be ejected with great force and to fly several metres. These flying chips present a hazard that is deflected with safety glasses, face shields, and other personal protective equipment, as well as the sheet-metal enclosures (and polycarbonate windows) that surround most commercial computer numerical control (CNC) machine tools.\nFlammability.\nDue to its high surface area, swarf composed of some reactive metals can be highly flammable. Caution should be exercised to avoid ignition sources when handling or storing swarf in loose form, especially swarf of pure magnesium, magnesium alloy, pure titanium, titanium alloy, iron, and non-stainless steel.\nSwarf stored in piles or bins may also spontaneously combust, especially if the swarf is coated with cutting oil.\nTo extinguish swarf fires, a special fire extinguisher is needed, designed for fighting (metal) fires.\nToxicity.\nSome common engineering materials such as beryllium are hazardous when finely divided and appropriate measures should be taken to prevent exposure.\nChip breaking.\nOptimum cutting efficiencies often generate long spring-like swarf. This is hard to deal with as it is bulky and can clog the nozzle of a shop vac. Clean-up and disposal of this continuous-cutting swarf is made simpler by using a cutting tool with a chip-breaker. This results in denser, more manageable waste. Chip breaking tool geometry is generally designed to break the chip by having it curl back onto itself. This action produces many small spiral shaped rings instead of one long helical chip. \"Number Nine\" shaped chips or short swarf in general are preferred also because it helps prevent entangling the rotating machine.\nMachine cleaning and chip handling.\nDisposing of swarf is a tedious but necessary task. For ease of transport and handling, swarf may be compressed into \"bricks\", which greatly reduces associated problems with storing and cost; it also improves material handling for all concerned with its reclamation and recycling.\nRecycling.\nMetal swarf can usually be recycled, and this is the preferred method of disposal due to the environmental concerns regarding potential contamination with cutting fluid or tramp oil. The ideal way to remove these liquids is by the use of a centrifuge which will separate the fluids from the metal, allowing both to be reclaimed and prepared for further treatment. Small bundles of stainless steel or bronze swarf are sold as excellent scourers for dishwashing or cleaning encrustations of dirt. Recycling chips rather than putting them in the garbage stream (heading to landfilling or incineration) has various advantages:\nRequirements.\nMachine shops are typically required by the scrap collector to:", "Engineering,_Manufacturing": 0.9999911785, "qwen": "Yes"}
{"id": "31248331", "revid": "869314", "url": "https://en.wikipedia.org/wiki?curid=31248331", "title": "2001 J.League Cup", "text": "Statistics of J. League Cup, officially the 2001 J.League Yamazaki Nabisco Cup, in the 2001 season.\nOverview.\nIt was contested by 28 teams, and Yokohama F. Marinos won the championship.\nResults.\n1st round.\nThe first legs were played on 4 April, and the second legs were played on 18 April. 12 teams from the Division 1 and all 12 teams from the Division 2 entered this round.\n\n2nd round.\nThe first legs were played on 13 June, and the second legs were played on 20 June. The 4 remaining teams from the Division 1 entered this round.\n\nQuarterfinals.\nThe first legs were played on 8 August, and the second legs were played from 22 to 29 August.\n\nSemifinals.\nThe first legs were played on 26 September, and the second legs were played on 10 October.\n\nFinal.\nYokohama F. Marinos won the championship.", "Engineering,_Manufacturing": 0.9999665022, "qwen": "Yes"}
{"id": "31260053", "revid": "45708962", "url": "https://en.wikipedia.org/wiki?curid=31260053", "title": "Powder bed and inkjet head 3D printing", "text": "Binder jet 3D printing, known variously as \"Powder bed and inkjet\" and \"drop-on-powder\" printing, is a rapid prototyping and additive manufacturing technology for making objects described by digital data such as a CAD file. Binder jetting is one of the seven categories of additive manufacturing processes according to ASTM and ISO.\nHistory.\nThis technology was first developed at the Massachusetts Institute of Technology and patented in 1993. In 1996, the ExOne Company was granted an exclusive field-of-use patent for the technology, while Z Corporation, which was later acquired by 3D Systems, obtained a non-exclusive patent for use of the technology for metal casting purposes. The term \"Three-Dimensional Printing\" was trademarked by the research group at MIT, along with the abbreviation 3DP. As a result, the term \"3D printing\" originally referred uniquely to the binder jet printing process prior to gaining wider acceptance as a term referring to all additive manufacturing processes.\nDescription.\nAs in many other additive manufacturing processes the part to be printed is built up from many thin cross sections of the 3D model. An inkjet print head moves across a bed of powder, selectively depositing a liquid binding material. A thin layer of powder is spread across the completed section and the process is repeated with each layer adhering to the last.\nWhen the model is complete, unbound powder is automatically and/or manually removed in a process called \"de-powdering\" and may be reused to some extent.\nThe de-powdered part could optionally be subjected to various infiltrants or other treatments to produce properties desired in the final part.\nMaterials.\nIn the original implementations, starch and gypsum plaster fill the powder bed, the liquid \"binder\" being mostly water to activate the plaster. The binder also includes dyes (for color printing), and additives to adjust viscosity, surface tension, and boiling point to match print head specifications. The resulting plaster parts typically lack \"green strength\" and require infiltration by melted wax, cyanoacrylate glue, epoxy, etc. before regular handling.\nWhile not necessarily employing conventional inkjet technology, various other powder-binder combinations may be deployed to form objects by chemical or mechanical means. The resulting parts may then be subjected to different post-processing regimes, such as infiltration or bakeout. This may be done, for example, to eliminate the mechanical binder (e.g., by burning) and consolidate the core material (e.g., by melting), or to form a composite material blending the properties of powder and binder. Depending on the material, full color printing may or may not be an option. As of 2014, inventors and manufacturers have developed systems for forming objects from sand and calcium carbonate (forming a synthetic marble), acrylic powder and cyanoacrylate, ceramic powder and a liquid binder, sugar and water (for making candies), etc. One of the first commercially available products that incorporated the use of Graphene, was a powdered composite used in powder bed inkjet head 3D printing.\n3D printing technology has a limited potential to vary material properties in a single build, but is generally limited by the use of a common core material. In the original Z Corporation systems, cross-sections are typically printed with solid outlines (forming a solid shell) and a lower-density interior pattern to speed printing and ensure dimensional stability as the part cures.\nCharacteristics.\nIn addition to volumetric color by use of multiple print heads and colored binder, the 3D printing process is generally faster than other additive manufacturing technologies such as fused deposition modeling material jetting which require 100% of build and support material to be deposited at the desired resolution. In 3D printing, the bulk of each printed layer, regardless of complexity, is deposited by the same, rapid spreading process.\nAs with other powder-bed technologies, support structures are generally not required because loose powder supports overhanging features and stacked or suspended objects. The elimination of printed support structures can reduce build time and material use and simplify both equipment and post-processing. However, de-powdering itself can be a delicate, messy, and time-consuming task. Some machines therefore automate de-powdering and powder recycling to what extent feasible. Since the entire build volume is filled with powder, as with stereolithography, means to evacuate a hollow part must be accommodated in the design.\nLike other powder-bed processes, surface finish and accuracy, object density, and—depending on the material and process—part strength may be inferior to technologies such as stereolithography (SLA) or selective laser sintering (SLS). Although \"stair-stepping\" and asymmetrical dimensional properties are features of 3D printing as most other layered manufacturing processes, 3D printing materials are generally consolidated in such a way that minimizes the difference between vertical and in-plane resolution. The process also lends itself to rasterization of layers at target resolutions, a fast process that can accommodate intersecting solids and other data artifacts.\nPowder bed and inkjet 3D printers typically range in price from $50,000 to $2,000,000 . However, there is a hobbyist DIY kit selling from $800 to convert a consumer FDM printer to powder/inkjet printer.\nLimitations.\nParts printed using the binder jetting process are inherently porous and have an unfinished surface, as unlike powder bed fusion the powders are not physically melted and are joined by a binding agent. While the usage of a binding agent allows for high melting temperature (e.g. ceramic) and heat-sensitive (e.g. polymer) materials to be powdered and used for additive manufacturing, binder jetting parts require additional post-processing that can require more time than it takes to print the part, such as curing, sintering, and additional finishing .\nBinder jetting is particularly prone to the phenomena of powder bed depletion, which occurs when the binder is dropped onto the surface of the powder bed. This issue is particularly prevalent in binder jetting, as unlike traditional additive manufacturing processes (which utilize high heat to melt and fuse powders together), the \"jet\" of binder that is dropped onto the bed can cause large agglomerates of semi-bonded powder to be ejected from the surface, leaving behind subsurface depletion zones (for 30 μm SS316 powder, a depletion zone depth of 56±12μm was observed). The growth of depletion zones as subsequent layers of powder are deposited printed can have major ramifications on the quality of parts printed with binder jetting. Ejected agglomerates land on other regions of the bed, causing the surface of the bed to become less even, the dimensions of the final part to be warped and inaccurate, and large subsurface pores to form. Residual defects and stress may also be present throughout, which reduce the strength of the already weaker part (due to the inherent porosity of the binder jetted part) .\nThese factors limit the usage of binder jetting for high-performance applications, such as for aerospace, as binder jetted parts are generally weaker than those printed with powder bed fusion processes. However, binder jetting is perfect for rapid prototyping and production of low-cost metal parts .", "Engineering,_Manufacturing": 0.9997138381, "qwen": "Yes"}
{"id": "63981705", "revid": "10803629", "url": "https://en.wikipedia.org/wiki?curid=63981705", "title": "Suzuki HEARTECT platform", "text": "The HEARTECT platform is an automobile platform that underpins various Suzuki models since 2014.\nConstruction.\nThe platform is claimed to utilize \"Advanced High Tensile Steel\" and \"Ultra High Tensile Steel\", which are intended to increase occupant safety in case of a collision. Suzuki also claims that the platform offers increased body stiffness, allowing for better ride quality and handling. Additionally, via a reduction in weight of up to , the platform helps achieve an improved power to weight ratio.\nThe platform is shown to utilize MacPherson strut front suspension.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "18728089", "revid": "37823666", "url": "https://en.wikipedia.org/wiki?curid=18728089", "title": "Aerospace bearing", "text": "Aerospace bearings are the bearings installed in aircraft and aerospace systems including commercial, private, military, or space applications.\nMaterials include M50 tool steel (AMS6491), carbon chrome steel (AMS6444), the corrosion resistant AMS5930, 440C stainless steel, silicon nitride (ceramic) and titanium carbide-coated 440C.\nTypically, special attention is given to the material specification, non-destructive testing, and to the traceability of the bearing (a system of documents that enables an engineer to trace a bearing, typically back to its manufacturing batch and material supply).\nDesign.\nWhen designing aerospace bearings, it is important to take a few things into account, including:\nIn order to assure bearing performance, it is necessary for the bearing steel to be of high quality. Jet engine bearings are typically manufactured from metals manufactured using a vacuum arc remelt to enable material requirements to be met.\nJet engine shaft bearings and accessory drive shaft bearings typically use single piece or two piece machined retainers. The pressed steel or moulded retainers found on mass-produced bearings are not used.\nTemperature and moisture resistant oils, greases and lubricants are normally specified. If the lubricant is not correct the performance of the bearing will be compromised.\nApplication.\nIn jet engines bearings can operate at over 200 degrees Celsius (400 °F) and at speeds over 10,000 rpm for the turbine shafts to over 30,000 rpm in the accessory drives. In wing control surface applications temperatures as low as may be encountered.\nMonitoring.\nBearings are a vital factor in many products and assemblies and their performance is often monitored continuously. In jet engines the oil supply is monitored to detect the presence of metallic debris that could identify a failure either of the bearings or of other components whose failure may contaminate the bearings.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "40678182", "revid": "41840956", "url": "https://en.wikipedia.org/wiki?curid=40678182", "title": "Process window", "text": "The process window is a graph with a range of parameters for a specific manufacturing process that yields a defined result. Typically multiple parameters are plotted in such a graph with a central region where the process behaves well, while the outer borders define regions where the process becomes unstable or returns an unfavourable result. A statistical evaluation of the process performance is further performed by the calculation of the associated Process Window Index.\nApplications.\nTypical applications are found in photolithography where the response of a photoresist to parameters like temperature, radiation intensity, critical dimension and sidewall angle of the structures, etc. are plotted versus an optical parameter such as the numerical aperture to optimize the design of an exposure tool or to achieve a reproducible result and high yield.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "40678541", "revid": "22942118", "url": "https://en.wikipedia.org/wiki?curid=40678541", "title": "Electronics cooling", "text": "Electronics cooling encompasses thermal design, analysis and experimental characterization of electronic systems as a discrete discipline with the product creation process for an electronics product, or an electronics sub-system within a product (e.g. an engine control unit (ECU) for a car). On-line sources of information are available and a number of books have been published on this topic.\nComputer cooling is a sub-topic. Heat sinks are devices that are used to extend the surface area of electronic components available for air cooling, helping to lower the components case temperature. Fans are used to increase the air flow.\nThermal design and analysis is performed using hand calculations or spreadsheets, based on design rules or heat transfer correlations. Computer-aided engineering tools such as computational fluid dynamics are also used.\nActive electronics cooling.\nBesides passive heat conduction, active cooling consuming electricity can be achieved through the thermoelectric coolers.\nWhen electrical voltage is added to an \"n\"-type (\"p\"-type) semiconductor material, the electric filed will drive electrons (holes) from one end to the other, which will also carry the electronic kinetic energy and entropy. A temperature gradient will be finally built up to balance the driven force of electrical field. This is called the Peltier effect, and the refrigeration or cooling device made based on this effect is called the Peltier cooler. One Peltier cooler is at least consisted of one \"n\"-leg and one \"p\"-leg, which is also called a Peltier junction. Although, Peltier coolers are generally only around 10-15% as efficient as a reversed Carnot cycle, or as 40–60% efficient as a vapor-compression cycle, it may be the only choice for applications in some special scenarios, including electronics on satellites, in submarines, and at an extremely compact space, due to their solid state nature, low maintenance need, compact size and noise-free operation.\nMultiple Peltier junctions, taking care of each specific temperature window, can usually be stacked to further enhance the overall performance on electronics cooling. As active heat pumps which consume power, thermoelectric coolers can produce temperatures below ambient, which is impossible with passive heatsinks, radiator-cooled liquid cooling, or heatpipe HSFs. However, while pumping heat, a Peltier module will typically consume more electric power than the heat amount being pumped.", "Engineering,_Manufacturing": 0.9999748468, "qwen": "Yes"}
{"id": "70176475", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=70176475", "title": "Closed-loop box reuse", "text": "Closed Loop Box Reuse, is the process by which boxes or other containers are reused many times. It is a form of reusable packaging.\nThis is sometimes suited to a large business where containers are used and reused within the location; the custody of containers stays in secure control. Business-to-business commerce also allows controlled return by reverse logistics; a “closed system” and a circular life cycle.\nContainers may be constructed of corrugated fiberboard, corrugated plastic, molded plastic, or other materials. Identification of containers by labels, bar codes, various colored latches or RFID chips is common.\nDescription.\nWhen closed loop supply chains exist or can be created during work in process or progress, boxes are frequently opened and closed to remove and replace contents for inspections, calibration, testing, quality assurance, powder coating or other purposes. Eliminating tape during this process eliminates human injuries from box cutters, blades and knives as well as eliminating damage to box contents.\nA means of closing the containers is usually needed such as lids, covers, straps, staples, tape, latches, clips, bands, Hook-and-loop fasteners, etc. When using devices that hold flaps down and out of the way, they can be stacked and stored open or moved about on carts, conveyors, trucks or pallets while remaining open. This saves time and labor while enhancing [{sustainability]} by reusing clips and undamaged boxes. It is important that these temporary means of closure and reopening does not deface or damage the cartons.\nAt endpoints in these single or multi-site linear or circular closed loops, the temporary closures are removed for reuse and boxes taped for secure shipping to their next or a final destination.\nAlternatively, these fiberboard boxes may be collapsed with their closing devices attached and returned to the loop origin in a flattened manner. This reduces time and spares human injuries caused by cutting tape on tops and bottoms. It also lowers costs for freight and allows for speedy reconstruction of cartons in a tapeless, closed loop.\nContainers can be reused dozens of times before disposal or recycling. This leverages supply chain cost savings at the same time it embraces supply chain sustainability.\nHistory.\nReuse of. boxes and other containers has been common for many years. For example, the automotive industry has long used reusable racks, totes, and boxes. One type of “closed loop box reuse” was used by Jack D. and James F. Wilson, coinventors of supportive devices developed to keep cardboard box flaps closed or held open without the use of tape. The closed loop term describes a circular life for boxes and cartons made possible by the help of such supportive devices.\nClosed-loop box reuse is the process by which packaging materials can be used and reused to minimize waste. Similar and overlapping terms commonly used are closed-loop recycling, returnable packaging, reusable packaging, sustainable supply chains and circular economy. Laws have been passed in Maine and Oregon to make it the responsibility of producers of waste to pay into a fund based on the amount and the ability of the materials used in their packaging to be recycled. These funds will be employed to reimburse municipalities for eligible recycling and waste management costs, make investments in recycling infrastructure, and help citizens understand how to recycle.\nA circular economy is a large-scale model that involves the sharing, leasing, reusing, repairing, refurbishing and recycling of existing material in a global environment. Reverse logistics is an alternative to a traditional linear economy (take, make, waste). It seeks to reduce waste, recover resources at the end of a product's life, and channel it back into production, thus, significantly reducing pressure on the environment. Closed-loop box reuse shares similar goals and perspectives but is specific to the circular life cycle of fiberboard boxes in systems where reuse is the focus.\nEnvironmental impact.\nThe goal of closed-loop fiberboard box reuse is to reduce waste and pollution. The supply chain accounts for more than 90% of the environmental impact experienced by most consumer goods companies, more than 800 million tons of cardboard and paper are disposed of yearly in the USA. Reusing one ton of fiberboard boxes saves 390 kWh of energy, 46 gallons of oil and 700 gallons of water.\nRecycling (or reusing) that same ton of corrugated board produces less than 50% of sulfur-dioxide than if made from raw materials and saves more than 9 cubic yards of landfill. In 2018, over 17 million tons of paper and paperboard were landfilled in the U.S. It is the largest component of municipal solid waste.\nClosed loop box reuse allows companies to meet their Circular Economy, ISO, Six Sigma, Lean Manufacturing or Zero Waste goals. Closed loop opportunities exist in assembly lines, pick and pack fulfillment centers, kitting operations, warehouse management systems, and moving and storage businesses.", "Engineering,_Manufacturing": 0.9998320937, "qwen": "Yes"}
{"id": "70180865", "revid": "16635116", "url": "https://en.wikipedia.org/wiki?curid=70180865", "title": "Die shot", "text": "A die shot or die photography is a photo or recording of the layout of an integrated circuit, showings its design with any packaging removed. A die shot can be compared with the cross-section of an (almost) two-dimensional computer chip, on which the design and construction of various tracks and components can be clearly seen. Due to the high complexity of modern computer chips, die-shots are often displayed colourfully, with various parts coloured using special lighting or even manually.\nMethods.\nA die shot is a picture of a computer chip without its housing. There are two ways to capture such a chip \"naked\" on a photo; by either taking the photo before a chip is packaged or by removing its package.\nAvoiding the package.\nTaking a photo before the chip ends up in a housing is typically preserved to the chip manufacturer, because the chip is packed fairly quickly in the production process to protect the sensitive very small parts against external influences. However, manufacturers may be reluctant to share die shots to prevent competitors from easily gaining insight into the technological progress and complexity of a chip.\nRemoving the package.\nRemoving the housing from a chip is typically a chemical process - a chip is so small and the parts are so microscopic that opening a housing (also named delidding) with tools such as saws, sanders or dremels could damage the chip in such a way that a die shot is no longer or less useful. For example, sulphuric acid can be used to dissolve the plastic housing of a chip. This is not a harmless process - sulphuric acid can cause a lot of health damage to people, animals and the environment. Chips are immersed in a glass jar with sulphuric acid, after which the sulphuric acid is boiled for up to 45 minutes at a temperature of 337 degrees Celsius. Once the plastic housing has decayed, there may be other processes to remove leftover carbon, such as with a hot bath of concentrated nitric acid. After this, the contents of a chip are relatively exposed and a picture can be made of the chip with macrophotography or microphotography.", "Engineering,_Manufacturing": 0.9940515161, "qwen": "Yes"}
{"id": "35336563", "revid": "44357303", "url": "https://en.wikipedia.org/wiki?curid=35336563", "title": "Onto Innovation", "text": "Onto Innovation Inc. is an American semiconductor company formed in 2019 from the merger of Rudolph Technologies, Inc. and Nanometrics Incorporated. Onto Innovation is traded as on the New York Stock Exchange, it is a provider of process and process control equipment and software for microelectronic manufacturing industries (primarily semiconductor). The company's product offering includes automated defect inspection and metrology systems, probe card test and analysis systems, and lithography step-and-repeat systems. In addition, Onto Innovation provides a broad range of software products designed to improve yield, control processes and reduce manufacturing costs.\nHistory.\nRudolph Research: 1940–1995.\nRudolph Technologies, Inc. (RTI) traces its origins to 1940, when Otto Curt Rudolph formed O.C. Rudolph & Sons, Inc. Originally an importer of microscopes and scientific instruments, this RTI predecessor was renamed in October 1970 to Rudolph Research Corporation. The company designed optical equipment for laboratories and universities.\nThe company Otto Rudolph established continued to evolve, making breakthroughs in ellipsometry including the first production-oriented ellipsometer for thin, transparent film measurements. The company continued development of its metrology products, securing new patents along the way.\nNanometrics: 1975–2019.\nNanometrics was founded in 1975 and was a pioneer and innovator in the field of optical metrology. In 1984, the company started publicly trading.\nFormation of Rudolph Technologies: 1996–1999.\nIn June 1996, Richard Spanier, Ph.D., chief executive officer of Rudolph Research, forged a partnership agreement with Boston-based Riverside Partners and New York-based Liberty Partners who, along with others, invested in the company. At that time, Dr. Spanier retired his active role in the company and semiconductor industry veteran Paul F. McLaughlin was named as CEO. In August 1999, the name of the company was changed to Rudolph Technologies, Inc.\nIn November 1999, RTI made its initial public offering of common stock. Revenues grew dramatically, reaching a record $38.1 million. A new facility opened early in the year, and the company launched a new product, the MetaPULSE® line of copper film measurement tools.\nRudolph Technologies: 2000–2019.\nIn July 2002, RTI agreed to acquire the Richardson, Texas-based defect control company ISOA, Inc. A spin-off from Texas Tech University's International Center for Informatics Research, ISOA had been licensing technology to the semiconductor industry for about 16 years, offering defect detection software. The deal was completed in September, with ISOA becoming RTI's Yield Metrology Group.\nSeveral months later, RTI expanded into China by establishing an office in Shanghai's Pudong industrial area. In subsequent years, the company established additional offices in all semiconductor manufacturing regions of the world including Japan, Europe, South Korea, Taiwan and Singapore.\nIn 2006, a merger was completed with Minnesota-based August Technology Corporation, growing Rudolph's workforce to 550 employees. This acquisition brought Rudolph into the ‘back-end’ of the manufacturing process.\nIn 2007, the company acquired the semiconductor business of Washington-based Applied Precision LLC, adding probe card test and analysis to the company's portfolio. The acquisition of RVSI Inspection LLC and its Wafer Scanner inspection system was announced in 2008. Adventa Control Technologies, Inc., a provider of process control software, was acquired in 2009, and an acquisition of MKS Instruments, Inc.’s Yield Dynamics business was completed in 2010. Rudolph announced two acquisitions in 2012. NanoPhotonics GmbH, Mainz, Germany (unpatterned wafer inspection); and Azores Corp., Wilmington, MA (Rudolph's entry into the advanced packaging and FPD lithography markets). In 2013 Rudolph announced the acquisition of selected assets of Tamar Technology, Newbury Park, CA, a supplier of 3D metrology technologies. Rudolph acquired the inspection technology of Stella Alliance in 2015, adding patents to enhance its inspection capability.\nIn November 2015, Rudolph announced the retirement of Paul F. McLaughlin and appointment of Michael P. Plisinski as CEO and Director.\nAs of January 19, 2017, Rudolph Technologies Inc. had a market capitalization of about $713 million.\nIn January 2017, Voce Capital Management LLC in a letter to investors, urged merging semiconductor-equipment makers Rudolph Technologies Inc. and Nanometrics Inc. The merger eventually occurred and closed on October 30, 2019. According to the Joint Proxy Statement announcing the terms of the merger, talks began in the first quarter of 2016 and continuing into 2017, Nanometrics and Rudolph engaged in discussions concerning a potential business combination between the two companies, to be structured as a merger of equals transaction, which discussions between the parties are referred to as the 2017 discussions. In connection with the 2017 discussions, in February 2016, Nanometrics and Rudolph entered into a mutual confidentiality agreement, which was subsequently extended in January 2017.\nOn October 25, 2019, Rudolph merged with Nanometrics Incorporated to become Onto Innovation, trading as .\nThe company is now headquartered in Wilmington, Massachusetts, with additional U.S. operations in New Jersey, Minnesota, California, Texas, Oregon and Washington. Manufacturing operations for inspection and some metrology products are consolidated in Minnesota; most metrology manufacturing operations is in California; stepper manufacturing is located in Wilmington, Massachusetts.\nProducts and services.\nSemiconductor fabrication, packaging and testing.\nSemiconductor device fabrication is the process used to create the integrated circuits that are found in commonly used electronic devices and electrical equipment. It is a multiple-step process during which electronic circuits are gradually built by adding elements and layers of material on a substrate made of pure silicon, or various compounds in the case of specialized applications, hundreds of steps performed by specialized process tools are required before the wafer moves to a final packaging facility.\nThe focus of packaging and assembly is to ensure an electrical connection from the die to the circuit board, to encapsulate the package for mechanical integrity and to withstand thermal variations. The era of slim form-factor devices, such as smart phones, implies high level of functionality in very dense footprint. Due to these requirements, the challenges in packaging, assembly and test have significantly increased and advanced packaging techniques such as bumping or through-silicon via are necessary.", "Engineering,_Manufacturing": 0.9979350567, "qwen": "Yes"}
{"id": "56702678", "revid": "1152308", "url": "https://en.wikipedia.org/wiki?curid=56702678", "title": "Officine Meccaniche (disambiguation)", "text": "Officine Meccaniche is an Italian car and truck manufacturing company.\nOfficine Meccaniche may also refer to:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "56722248", "revid": "892079", "url": "https://en.wikipedia.org/wiki?curid=56722248", "title": "Friction stir spot welding", "text": "Friction stir spot welding is a pressure welding process that operates below the melting point of the workpieces. It is a variant of friction stir welding.\nProcess description.\nIn friction stir spot welding, individual spot welds are created by pressing a rotating tool with high force onto the top surface of two sheets that overlap each other in the lap joint. The frictional heat and the high pressure plastify the workpiece material, so that the tip of the pin plunges into the joint area between the two sheets and stirs-up the oxides. The pin of the tool is plunged into the sheets until the shoulder is in contact with the surface of the top sheet. The shoulder applies a high forging pressure, which bonds the components metallurgically without melting. After a short dwell time, the tool is pulled out of the workpieces again so that a spot weld can be made about every 5 seconds.\nThe tool consists of a rotating pin and a shoulder. The pin is the part of the tool that penetrates into the materials. Both the pin and the shoulder may be profiled to push the plasticized material in a particular direction and to efficiently break-up and disperse the oxide skins on the adjacent surfaces. After retracting the tool, a hole remains, when using one-piece tools, which have already proven themselves as very reliable in the automotive and the rail vehicle industry. Often the rotating tool is surrounded by a non-rotating clamping ring with which the workpieces are pressed firmly against each other before and during welding by applying a clamping force. The clamping ring can also be used to reduce the pressing out of plasticized material to avoid the formation of burrs or beads to apply inert gas or to cool the tool via compressed air.\nThe most important process parameters are the speed and contact pressure. This results in the plunge feed rate for a given workpiece material. Modern spot welding guns can be used either via position control or force control or via a product-specific programmed force-displacement control. Often, position control is used until a certain displacement is reached, and then the control system is switched to force control during the dwell time. Even during the force-controlled dwell time, certain position values can be specified, which should not be undermatched or exceeded.\nSpot welding guns.\nFriction stir spot welding is performed with a spot welding gun, which is mounted on a console, flanged to an articulated robot or manually operated with a balancer to the component.\nProcess advantages.\nFriction spot welding is characterized by a number of process advantages. Any damage to the material caused by the extreme heat, such as that produced by laser or arc welding, will not occur. In particular, in the case of artificially aged aluminum alloys, the strength in the weld seam and the heat-affected zone is much higher than in conventional welding methods.\nIndustrial use.\nFriction stir spot welds have a high strength, so they are even suitable for parts that are exposed to particularly high loads. In addition to automotive and rail vehicle construction, the aerospace industry is developing the process e.g. for welding cockpit doors for helicopters. In the electrical industry aluminum and copper can be friction stir spot welded. Other applications are in façade and furniture manufacture, where the low heat input, especially in anodized sheets, leads to excellent optical properties.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "39492922", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=39492922", "title": "Rane (Madras)", "text": "Rane (Madras) Ltd is a part of the Rane group of companies involved in the manufacture and distribution of steering and suspension systems. The main components manufactured by the company include Manual Steering Gear Products (SGP) and Suspension & Steering Linkage Products (SSLP). The other products include tie rod assemblies, drag link assemblies, center link assemblies and gear shift ball joints. Automobile companies that use its products include Ashok Leyland, Volvo, M&M, Tafe, Tata among many others. Tata motors remains its major customer and is the primary parts manufacturer for Tata's Nano. The company has also set up a dedicated plant for Tata Nano in Sanand, Gujarat. The company was forced to change its manufacturing facility from West Bengal to Gujarat after Tata moved out.\nHistory.\nRane group of companies was founded by Shri T. R. Ganapathy Iyer in the year 1929 and the group was originally named as Rane (Madras) Ltd. It started off as a distributor of automobiles and parts. After his death, the business was taken over by his son-in-law Lakshmana Iyer Lakshminarayan, popularly known as LLN, among friends and business circles. Under the leadership of LLN, the company was shaped into an auto-component business house. LLN remained as the founder chairman of the group for over three decades.\nDuring the early periods. Rane Madras Ltd was engaged in trading only. Later in the year 1960, they completely dropped trading and started manufacturing and it all started with the manufacture of Tie Rod ends at their plant in Velachery, Chennai. Later; as the automobile industry flourished, the business spread to the manufacturing of other suspension and steering systems. As a major turn of events, in 2005 the company was de-merged from the group and the group holding company called Rane Holding Ltd (RHL) and several other subsidiary companies were formed. It was during this period that Rane (Madras) Ltd emerged as a public limited company. Later, Rane Holding Ltd made additional investment in the company, and thus Rane (Madras) Ltd became a wholly owned subsidiary of the Rane Holdings Ltd. It remained a major manufacturer and supplier of major OEMs in India and abroad.\nOver the years Rane (Madras) Ltd has grown to be the largest in the group, both in terms of size and turnover, with five manufacturing plants in Chennai and Kancheepuram in Tamil Nadu, Mysore in Karnataka, Thirubuvanai in Pondicherry and Pantnagar in Uttarakhand. Each of the company's production plants addresses a specific industry segment. The production facilities in Mysore cater to the tractor and commercial vehicle segment; the Pondicherry plant to the passenger car segment; the plant in Chennai caters to the light commercial vehicle, heavy commercial vehicle and utility vehicle segment; the Kancheepuram plant to the export market and the manufacturing facility in Pantnagar (Uttarakhand) supplies gears exclusively to Tata Motors Ltd. The company has also started setting up its plant in Gujarat\nIn 2013 this group merged with GTC inc. (Gaurav Jagannath Rane) Director & S.E.O.", "Engineering,_Manufacturing": 0.9985763431, "qwen": "Yes"}
{"id": "65399344", "revid": "666342", "url": "https://en.wikipedia.org/wiki?curid=65399344", "title": "Italian Union of Chemical, Energy and Manufacturing Workers", "text": "The Italian Union of Chemical, Energy and Manufacturing Workers (, UILCEM) was a trade union representing manufacturing and utility workers in Italy.\nThe union was founded on 25 March 1999, when the Italian Union of Chemical, Energy and Resource Workers merged with the Italian Union of Public Service Workers. Like both its predecessors, it affiliated to the Italian Union of Labour. In 2013, it merged with the Italian Union of Textile and Clothing Workers, to form the Italian Union of Textile, Energy and Chemical Workers.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "65897", "revid": "12639318", "url": "https://en.wikipedia.org/wiki?curid=65897", "title": "Wire wrap", "text": "Wire wrap is an electronic component assembly technique that was invented to wire telephone crossbar switches, and later adapted to construct electronic circuit boards. Electronic components mounted on an insulating board are interconnected by lengths of insulated wire run between their terminals, with the connections made by wrapping several turns of uninsulated sections of the wire around a component lead or a socket pin.\nWires can be wrapped by hand or by machine, and can be hand-modified afterwards. It was popular for large-scale manufacturing in the 1960s and early 1970s, and continues today to be used for short runs and prototypes. The method eliminates the design and fabrication of a printed circuit board. Wire wrapping is unusual among other prototyping technologies since it allows for complex assemblies to be produced by automated equipment, but then easily repaired or modified by hand.\nWire wrap construction can produce assemblies that are more reliable than printed circuits: connections are less prone to fail due to vibration or physical stresses on the base board, and the lack of solder eliminates soldering faults such as corrosion, cold joints and dry joints. The connections themselves are firmer and have lower electrical resistance due to cold welding of the wire to the terminal post at the corners.\nWire wrap was used for assembly of high frequency prototypes and small production runs, including gigahertz microwave circuits and supercomputers. It is unique among automated prototyping techniques in that wire lengths can be exactly controlled, and twisted pairs or magnetically shielded twisted quads can be routed together.\nWire wrap construction became popular around 1960 in circuit board manufacturing, and use has now sharply declined. Surface-mount technology has made the technique much less useful than in previous decades. Solder-less breadboards and the decreasing cost of professionally made PCBs have nearly eliminated this technology.\nHistory.\nManually wrapped wires were common in early 20th century point-to-point electronic construction methods in which a strong connection was needed to hold the components in place. Wires were wrapped by hand around binding posts or spade lugs and then soldered.\nModern wire wrapping technology was developed after WWII at Bell Laboratories as a means of making electrical connections in a new relay being designed for use in the Bell Telephone system. A design team headed by Arthur C. Keller developed the “Keller Wrap Gun”, and the entire wrap system was passed over to Western Electric for industrial application. After a “make or buy” committee at Western Electric decided to have the hand tool manufactured by an outside vendor, Western Electric sent the tool contract out for bids. Keller Tool of Grand Haven, Michigan, a supplier of rotary hand tools to Western Electric, won the contract and made several design changes to make the tool easier to manufacture and to use. Keller began manufacturing the tools in 1953, and subsequently obtained a license from Western Electric allowing sale of the technology on the open market. The tool was marketed under its original name – since the name of the manufacturer was coincidentally the same as the name of the inventor.\nIBM's first transistorized computers, introduced within the late 1950s, were built with the IBM Standard Modular System that used wire-wrapped backplanes.\nMethod.\nA correctly made wire-wrap connection for 30 or 28 AWG wire is seven turns (fewer for larger wire) of bare wire with half to one and a half turns of insulated wire at the bottom for strain relief. The square hard-gold-plated post thus forms 28 redundant contacts. The silver-plated wire coating cold-welds to the gold. If corrosion occurs, it occurs on the outside of the wire, not on the gas-tight contact where oxygen cannot penetrate to form oxides. A correctly designed wire-wrap tool applies up to twenty tons of force per square inch on each joint.\nThe electronic parts sometimes plug into sockets. The sockets are attached with cyanoacrylate (or silicone adhesive) to thin plates of glass-fiber-reinforced epoxy (fiberglass).\nThe sockets have square posts. The usual posts are square, high, and spaced at intervals. Premium posts are hard-drawn beryllium copper alloy plated with a of gold to prevent corrosion. Less-expensive posts are bronze with tin plating.\n30 gauge (~0.0509mm2) silver-plated soft copper wire is insulated with a fluorocarbon that does not emit dangerous gases when heated. The most common insulation is \"Kynar\". The 30 AWG Kynar wire is cut into standard lengths, then one inch of insulation is removed on each end.\nThere are three ways of placing wires on a board. In professionally built wire-wrap boards, long wires are placed first so that shorter wires mechanically secure the long wires. Also, to make an assembly more repairable, wires are applied in layers. The ends of each wire are always at the same height on the post, so that at most three wires need to be replaced to replace a wire. Also, to make the layers easier to see, they are made with different colors of insulation. In space-rated or airworthy wire-wrap assemblies, the wires are boxed, and may be conformally coated with wax to reduce vibration. Epoxy is never used for the coating because it makes an assembly unrepairable.\nTooling.\nA \"wire wrap tool\" has two holes. The wire and of insulated wire are placed in a hole near the edge of the tool. The hole in the center of the tool is placed over the post.\nThe tool is rapidly twisted. The result is that 1.5 to 2 turns of insulated wire are wrapped around the post, and above that, 7 to 9 turns of bare wire are wrapped around the post. The post has room for three such connections, although usually only one or two are needed. This facilitates manual wire-wrapping to be employed for modifications or repairs.\nThe turn and a half of insulated wire helps prevent wire fatigue where it meets the post.\nAbove the turn of insulated wire, the bare wire wraps around the post. The corners of the post bite in with pressures of tons per square inch. This forces all the gases out of the area between the wire's silver plate and the post's gold or tin corners. Further, with 28 such connections (seven turns on a four-cornered post), a very reliable connection exists between the wire and the post. Furthermore, the corners of the posts are quite \"sharp\": they have a quite-small radius of curvature.\nAutomation.\nAutomated wire-wrap machines, as manufactured by the Gardner Denver Company in the 1960s and 1970s, were capable of automatically routing, cutting, stripping and wrapping wires onto an electronic \"backplane\" or \"circuit board\". The machines were driven by wiring instructions encoded onto punched cards, Mylar punched hole tape, and early micro computers.\nThe earliest machines (14FB and 14FG models, for example) were initially configured as \"horizontal\", which meant that the wire wrap board was placed upside down (pins up) onto a horizontal tooling plate, which was then rolled into the machine and locked onto a rotating (TRP table rotational position of four positions) and shifting (PLP = pallet longitudinal position of 11 positions) pallet assembly. These machines included very large hydraulic units for powering the servos that drove the ball screw mounted \"A\" and \"B\" drive carriages, a tall electronics cabinet loaded with hundreds of IBM control relays, many dozens of solenoids for controlling the various pneumatic mechanical subsystems, and an IBM 029 card reader for positioning instructions. The automatic wire wrap machines themselves were quite large, tall and square. Servicing the machines was extremely complex, and often meant climbing inside them just to work on them. This could be quite dangerous if safety interlocks were not maintained properly.\nLater, somewhat smaller machines were \"vertical\" (14FV) which meant the boards were placed onto a tooling plate with pins facing the machine operator. Gone were the hydraulic units, in favor of direct drive motors to rotate the ball screws, with rotary encoders to provide positioning feedback. This generally provided better visibility of the product for the operator, although maximum wrap area was significantly less than the horizontal machines. Top speeds on horizontal machines were generally around 500-600 wires per hour, while the vertical machines could reach rates as high as 1200 per hour, depending on board quality and wiring configurations.\nConsiderations.\nWire-wrap works well with digital circuits with few discrete components, but is less convenient for analog systems with many discrete resistors, capacitors or other components (such elements can be soldered to a header and plugged into a wire wrap socket). The sockets are an additional cost compared to directly inserting integrated circuits into a printed circuit board, and add size and mass to a system. Multiple strands of wire may introduce cross-talk between circuits, of little consequence for digital circuits but a limitation for analog systems. The interconnected wires can radiate electromagnetic interference and have less predictable impedance than a printed circuit board. Wire-wrap construction cannot provide the ground planes and power distribution planes possible with multilayer printed circuit boards, increasing the possibility of noise.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "65910", "revid": "6727347", "url": "https://en.wikipedia.org/wiki?curid=65910", "title": "Printed circuit board", "text": "A printed circuit board (PCB), also called printed wiring board (PWB), is a medium used to connect or \"wire\" components to one another in a circuit. It takes the form of a laminated sandwich structure of conductive and insulating layers: each of the conductive layers is designed with an artwork pattern of traces, planes and other features (similar to wires on a flat surface) etched from one or more sheet layers of copper laminated onto and/or between sheet layers of a non-conductive substrate. Electrical components may be fixed to conductive pads on the outer layers in the shape designed to accept the component's terminals, generally by means of soldering, to both electrically connect and mechanically fasten them to it. Another manufacturing process adds vias: plated-through holes that allow interconnections between layers. \nPrinted circuit boards are used in nearly all electronic products. Alternatives to PCBs include wire wrap and point-to-point construction, both once popular but now rarely used. PCBs require additional design effort to lay out the circuit, but manufacturing and assembly can be automated. Electronic design automation software is available to do much of the work of layout. Mass-producing circuits with PCBs is cheaper and faster than with other wiring methods, as components are mounted and wired in one operation. Large numbers of PCBs can be fabricated at the same time, and the layout has to be done only once. PCBs can also be made manually in small quantities, with reduced benefits.\nPCBs can be single-sided (one copper layer), double-sided (two copper layers on both sides of one substrate layer), or multi-layer (outer and inner layers of copper, alternating with layers of substrate). Multi-layer PCBs allow for much higher component density, because circuit traces on the inner layers would otherwise take up surface space between components. The rise in popularity of multilayer PCBs with more than two, and especially with more than four, copper planes was concurrent with the adoption of surface mount technology. However, multilayer PCBs make repair, analysis, and field modification of circuits much more difficult and usually impractical.\nThe world market for bare PCBs exceeded $60.2 billion in 2014 and is estimated to reach $79 billion by 2024.\nHistory.\nPredecessors.\nBefore the development of printed circuit boards, electrical and electronic circuits were wired point-to-point on a chassis. Typically, the chassis was a sheet metal frame or pan, sometimes with a wooden bottom. Components were attached to the chassis, usually by insulators when the connecting point on the chassis was metal, and then their leads were connected directly or with jumper wires by soldering, or sometimes using crimp connectors, wire connector lugs on screw terminals, or other methods. Circuits were large, bulky, heavy, and relatively fragile (even discounting the breakable glass envelopes of the vacuum tubes that were often included in the circuits), and production was labor-intensive, so the products were expensive.\nDevelopment of the methods used in modern printed circuit boards started early in the 20th century. In 1903, a German inventor, Albert Hanson, described flat foil conductors laminated to an insulating board, in multiple layers. Thomas Edison experimented with chemical methods of plating conductors onto linen paper in 1904. Arthur Berry in 1913 patented a print-and-etch method in the UK, and in the United States Max Schoop obtained a patent to flame-spray metal onto a board through a patterned mask. Charles Ducas in 1925 patented a method of electroplating circuit patterns.\nPredating the printed circuit invention, and similar in spirit, was John Sargrove's 1936–1947 Electronic Circuit Making Equipment (ECME) that sprayed metal onto a Bakelite plastic board. The ECME could produce three radio boards per minute.\nEarly PCBs.\nThe Austrian engineer Paul Eisler invented the printed circuit as part of a radio set while working in the UK around 1936. In 1941 a multi-layer printed circuit was used in German magnetic influence naval mines. \nAround 1943 the USA began to use the technology on a large scale to make proximity fuzes for use in World War II. Such fuzes required an electronic circuit that could withstand being fired from a gun, and could be produced in quantity. The Centralab Division of Globe Union submitted a proposal which met the requirements: a ceramic plate would be screenprinted with metallic paint for conductors and carbon material for resistors, with ceramic disc capacitors and subminiature vacuum tubes soldered in place. The technique proved viable, and the resulting patent on the process, which was classified by the U.S. Army, was assigned to Globe Union. It was not until 1984 that the Institute of Electrical and Electronics Engineers (IEEE) awarded Harry W. Rubinstein the Cledo Brunetti Award for early key contributions to the development of printed components and conductors on a common insulating substrate. Rubinstein was honored in 1984 by his alma mater, the University of Wisconsin-Madison, for his innovations in the technology of printed electronic circuits and the fabrication of capacitors. This invention also represents a step in the development of integrated circuit technology, as not only wiring but also passive components were fabricated on the ceramic substrate.\nPost-war developments.\nIn 1948, the USA released the invention for commercial use. Printed circuits did not become commonplace in consumer electronics until the mid-1950s, after the \"Auto-Sembly\" process was developed by the United States Army. At around the same time in the UK work along similar lines was carried out by Geoffrey Dummer, then at the RRDE.\nMotorola was an early leader in bringing the process into consumer electronics, announcing in August 1952 the adoption of \"plated circuits\" in home radios after six years of research and a $1M investment. Motorola soon began using its trademarked term for the process, PLAcir, in its consumer radio advertisements. Hallicrafters released its first \"foto-etch\" printed circuit product, a clock-radio, on 1 November 1952. \nEven as circuit boards became available, the point-to-point chassis construction method remained in common use in industry (such as TV and hi-fi sets) into at least the late 1960s. Printed circuit boards were introduced to reduce the size, weight, and cost of parts of the circuitry. In 1960, a small consumer radio receiver might be built with all its circuitry on one circuit board, but a TV set would probably contain one or more circuit boards.\nOriginally, every electronic component had wire leads, and a PCB had holes drilled for each wire of each component. The component leads were then inserted through the holes and soldered to the copper PCB traces. This method of assembly is called \"through-hole\" construction. In 1949, Moe Abramson and Stanislaus F. Danko of the United States Army Signal Corps developed the \"Auto-Sembly\" process in which component leads were inserted into a copper foil interconnection pattern and dip soldered. The patent they obtained in 1956 was assigned to the U.S. Army. With the development of board lamination and etching techniques, this concept evolved into the standard printed circuit board fabrication process in use today. Soldering could be done automatically by passing the board over a ripple, or wave, of molten solder in a wave-soldering machine. However, the wires and holes are inefficient since drilling holes is expensive and consumes drill bits and the protruding wires are cut off and discarded.\nFrom the 1980s onward, small surface mount parts have been used increasingly instead of through-hole components; this has led to smaller boards for a given functionality and lower production costs, but with some additional difficulty in servicing faulty boards.\nIn the 1990s the use of multilayer surface boards became more frequent. As a result, size was further minimized and both flexible and rigid PCBs were incorporated in different devices. In 1995 PCB manufacturers began using microvia technology to produce High-Density Interconnect (HDI) PCBs.\nRecent advances.\nRecent advances in 3D printing have meant that there are several new techniques in PCB creation. 3D printed electronics (PEs) can be utilized to print items layer by layer and subsequently the item can be printed with a liquid ink that contains electronic functionalities.\nHDI (High Density Interconnect) technology allows for a denser design on the PCB and thus potentially smaller PCBs with more traces and/or components in a given area. As a result, the paths between components can be shorter. HDIs use blind/buried vias, or a combination that includes microvias. With multi-layer HDI PCBs the interconnection of several vias stacked on top of each other (stacked vías, instead of one deep buried via) can be made stronger, thus enhancing reliability in all conditions. The most common applications for HDI technology are computer and mobile phone components as well as medical equipment and military communication equipment. A 4-layer HDI microvia PCB is equivalent in quality to an 8-layer through-hole PCB, so HDI technology can reduce costs.\nComposition.\nA basic PCB consists of a flat sheet of insulating material and a layer of copper foil, laminated to the substrate. Chemical etching divides the copper into separate conducting lines called tracks or \"circuit traces\", pads for connections, vias to pass connections between layers of copper, and features such as solid conductive areas for electromagnetic shielding or other purposes. The tracks function as wires fixed in place, and are insulated from each other by air and the board substrate material. The surface of a PCB may have a coating that protects the copper from corrosion and reduces the chances of solder shorts between traces or undesired electrical contact with stray bare wires. For its function in helping to prevent solder shorts, the coating is called solder resist or solder mask.\nThe pattern to be etched into each copper layer of a PCB is called the \"artwork\". The etching is usually done using photoresist which is coated onto the PCB, then exposed to light projected in the pattern of the artwork. The resist material protects the copper from dissolution into the etching solution. The etched board is then cleaned. A PCB design can be mass-reproduced in a way similar to the way photographs can be mass-duplicated from film negatives using a photographic printer.\nFR-4 glass epoxy is the most common insulating substrate. Another substrate material is cotton paper impregnated with phenolic resin, often tan or brown.\nWhen a PCB has no components installed, it is less ambiguously called a \"printed wiring board\" (\"PWB\") or \"etched wiring board\". However, the term \"printed wiring board\" has fallen into disuse. A PCB populated with electronic components is called a \"printed circuit assembly\" (\"PCA\"), \"printed circuit board assembly\" or \"PCB assembly\" (\"PCBA\"). In informal usage, the term \"printed circuit board\" most commonly means \"printed circuit assembly\" (with components). The IPC preferred term for an assembled board is \"circuit card assembly\" (\"CCA\"), and for an assembled backplane it is \"backplane assembly\". \"Card\" is another widely used informal term for a \"printed circuit assembly\".\nFor example, expansion card.\nA PCB may be printed with a legend identifying the components, test points, or identifying text. Originally, silkscreen printing was used for this purpose, but today other, finer quality printing methods are usually used. Normally the legend does not affect the function of a PCBA.\nLayers.\nA printed circuit board can have multiple layers of copper which almost always are arranged in pairs. The number of layers and the interconnection designed between them (vias, PTHs) provide a general estimate of the board complexity. Using more layers allow for more routing options and better control of signal integrity, but are also time consuming and costly to manufacture. Likewise, selection of the vias for the board also allow fine tuning of the board size, escaping of signals off complex ICs, routing, and long term reliability, but are tightly coupled with production complexity and cost. \nOne of the simplest boards to produce is the two-layer board. It has copper on both sides that are referred to as external layers; multi layer boards sandwich additional internal layers of copper and insulation. After two-layer PCBs, the next step up is the four-layer. The four layer board adds significantly more routing options in the internal layers as compared to the two layer board, and often some portion of the internal layers is used as ground plane or power plane, to achieve better signal integrity, higher signaling frequencies, lower EMI, and better power supply decoupling.\nIn multi-layer boards, the layers of material are laminated together in an alternating sandwich: copper, substrate, copper, substrate, copper, etc.; each plane of copper is etched, and any internal vias (that will not extend to both outer surfaces of the finished multilayer board) are plated-through, before the layers are laminated together. Only the outer layers need be coated; the inner copper layers are protected by the adjacent substrate layers.\nComponent mounting.\n\"Through hole\" components are mounted by their wire leads passing through the board and soldered to traces on the other side. \"Surface mount\" components are attached by their leads to copper traces on the same side of the board. A board may use both methods for mounting components. PCBs with only through-hole mounted components are now uncommon. Surface mounting is used for transistors, diodes, IC chips, resistors, and capacitors. Through-hole mounting may be used for some large components such as electrolytic capacitors and connectors.\nThe first PCBs used through-hole technology, mounting electronic components by leads inserted through holes on one side of the board and soldered onto copper traces on the other side. Boards may be single-sided, with an unplated component side, or more compact double-sided boards, with components soldered on both sides. Horizontal installation of through-hole parts with two axial leads (such as resistors, capacitors, and diodes) is done by bending the leads 90 degrees in the same direction, inserting the part in the board (often bending leads located on the back of the board in opposite directions to improve the part's mechanical strength), soldering the leads, and trimming off the ends. Leads may be soldered either manually or by a wave soldering machine. Through-hole manufacture adds to board cost by requiring many holes to be drilled accurately, and it limits the available routing area for signal traces on layers immediately below the top layer on multi-layer boards, since the holes must pass through all layers to the opposite side. Once surface-mounting came into use, small-sized SMD components were used where possible, with through-hole mounting only of components unsuitably large for surface-mounting due to power requirements or mechanical limitations, or subject to mechanical stress which might damage the PCB (e.g. by lifting the copper off the board surface).\nSurface-mount technology emerged in the 1960s, gained momentum in the early 1980s, and became widely used by the mid-1990s.\nComponents were mechanically redesigned to have small metal tabs or end caps that could be soldered directly onto the PCB surface, instead of wire leads to pass through holes. Components became much smaller and component placement on both sides of the board became more common than with through-hole mounting, allowing much smaller PCB assemblies with much higher circuit densities.\nSurface mounting lends itself well to a high degree of automation, reducing labor costs and greatly increasing production rates compared with through-hole circuit boards. Components can be supplied mounted on carrier tapes. Surface mount components can be about one-quarter to one-tenth of the size and weight of through-hole components, and passive components much cheaper. However, prices of semiconductor surface mount devices (SMDs) are determined more by the chip itself than the package, with little price advantage over larger packages, and some wire-ended components, such as 1N4148 small-signal switch diodes, are actually significantly cheaper than SMD equivalents.\nElectrical properties.\nEach trace consists of a flat, narrow part of the copper foil that remains after etching. Its resistance, determined by its width, thickness, and length, must be sufficiently low for the current the conductor will carry. Power and ground traces may need to be wider than signal traces. In a multi-layer board one entire layer may be mostly solid copper to act as a ground plane for shielding and power return. For microwave circuits, transmission lines can be laid out in a planar form such as stripline or microstrip with carefully controlled dimensions to assure a consistent impedance. In radio-frequency and fast switching circuits the inductance and capacitance of the printed circuit board conductors become significant circuit elements, usually undesired; conversely, they can be used as a deliberate part of the circuit design, as in distributed-element filters, antennae, and fuses, obviating the need for additional discrete components. High density interconnects (HDI) PCBs have tracks and/or vias with a width or diameter of under 152 micrometers. \nMaterials.\nLaminates.\nLaminates are manufactured by curing layers of cloth or paper with thermoset resin under pressure and heat to form an integral final piece of uniform thickness. They can be up to in width and length. Varying cloth weaves (threads per inch or cm), cloth thickness, and resin percentage are used to achieve the desired final thickness and dielectric characteristics. Available standard laminate thickness are listed in\nANSI/IPC-D-275.\nThe cloth or fiber material used, resin material, and the cloth to resin ratio determine the laminate's type designation (FR-4, CEM-1, G-10, etc.) and therefore the characteristics of the laminate produced. Important characteristics are the level to which the laminate is fire retardant, the dielectric constant (er), the loss tangent (tan δ), the tensile strength, the shear strength, the glass transition temperature (Tg), and the Z-axis expansion coefficient (how much the thickness changes with temperature).\nThere are quite a few different dielectrics that can be chosen to provide different insulating values depending on the requirements of the circuit. Some of these dielectrics are polytetrafluoroethylene (Teflon), FR-4, FR-1, CEM-1 or CEM-3. Well known pre-preg materials used in the PCB industry are FR-2 (phenolic cotton paper), FR-3 (cotton paper and epoxy), FR-4 (woven glass and epoxy), FR-5 (woven glass and epoxy), FR-6 (matte glass and polyester), G-10 (woven glass and epoxy), CEM-1 (cotton paper and epoxy), CEM-2 (cotton paper and epoxy), CEM-3 (non-woven glass and epoxy), CEM-4 (woven glass and epoxy), CEM-5 (woven glass and polyester). Thermal expansion is an important consideration especially with ball grid array (BGA) and naked die technologies, and glass fiber offers the best dimensional stability.\nFR-4 is by far the most common material used today. The board stock with unetched copper on it is called \"copper-clad laminate\".\nWith decreasing size of board features and increasing frequencies, small nonhomogeneities like uneven distribution of fiberglass or other filler, thickness variations, and bubbles in the resin matrix, and the associated local variations in the dielectric constant, are gaining importance.\nKey substrate parameters.\nThe circuitboard substrates are usually dielectric composite materials. The composites contain a matrix (usually an epoxy resin) and a reinforcement (usually a woven, sometimes nonwoven, glass fibers, sometimes even paper), and in some cases a filler is added to the resin (e.g. ceramics; titanate ceramics can be used to increase the dielectric constant).\nThe reinforcement type defines two major classes of materials: woven and non-woven. Woven reinforcements are cheaper, but the high dielectric constant of glass may not be favorable for many higher-frequency applications. The spatially nonhomogeneous structure also introduces local variations in electrical parameters, due to different resin/glass ratio at different areas of the weave pattern. Nonwoven reinforcements, or materials with low or no reinforcement, are more expensive but more suitable for some RF/analog applications.\nThe substrates are characterized by several key parameters, chiefly thermomechanical (glass transition temperature, tensile strength, shear strength, thermal expansion), electrical (dielectric constant, loss tangent, dielectric breakdown voltage, leakage current, tracking resistance...), and others (e.g. moisture absorption).\nAt the glass transition temperature the resin in the composite softens and significantly increases thermal expansion; exceeding Tg then exerts mechanical overload on the board components - e.g. the joints and the vias. Below Tg the thermal expansion of the resin roughly matches copper and glass, above it gets significantly higher. As the reinforcement and copper confine the board along the plane, virtually all volume expansion projects to the thickness and stresses the plated-through holes. Repeated soldering or other exposition to higher temperatures can cause failure of the plating, especially with thicker boards; thick boards therefore require a matrix with a high Tg.\nThe materials used determine the substrate's dielectric constant. This constant is also dependent on frequency, usually decreasing with frequency. As this constant determines the signal propagation speed, frequency dependence introduces phase distortion in wideband applications; as flat a dielectric constant vs frequency characteristics as is achievable is important here. The impedance of transmission lines decreases with frequency, therefore faster edges of signals reflect more than slower ones.\nDielectric breakdown voltage determines the maximum voltage gradient the material can be subjected to before suffering a breakdown (conduction, or arcing, through the dielectric).\nTracking resistance determines how the material resists high voltage electrical discharges creeping over the board surface.\nLoss tangent determines how much of the electromagnetic energy from the signals in the conductors is absorbed in the board material. This factor is important for high frequencies. Low-loss materials are more expensive. Choosing unnecessarily low-loss material is a common engineering error in high-frequency digital design; it increases the cost of the boards without a corresponding benefit. Signal degradation by loss tangent and dielectric constant can be easily assessed by an eye pattern.\nMoisture absorption occurs when the material is exposed to high humidity or water. Both the resin and the reinforcement may absorb water; water also may be soaked by capillary forces through voids in the materials and along the reinforcement. Epoxies of the FR-4 materials are not too susceptible, with absorption of only 0.15%. Teflon has very low absorption of 0.01%. Polyimides and cyanate esters, on the other side, suffer from high water absorption. Absorbed water can lead to significant degradation of key parameters; it impairs tracking resistance, breakdown voltage, and dielectric parameters. Relative dielectric constant of water is about 73, compared to about 4 for common circuit board materials. Absorbed moisture can also vaporize on heating, as during soldering, and cause cracking and delamination, the same effect responsible for \"popcorning\" damage on wet packaging of electronic parts. Careful baking of the substrates may be required to dry them prior to soldering.\nCommon substrates.\nOften encountered materials:\nLess-often encountered materials:\nCopper thickness.\nCopper thickness of PCBs can be specified directly or as the weight of copper per area (in ounce per square foot) which is easier to measure. One ounce per square foot is 1.344 mils or 34 micrometers thickness. \"Heavy copper\" is a layer exceeding three ounces of copper per ft2, or approximately 0.0042 inches (4.2 mils, 105 μm) thick. Heavy copper layers are used for high current or to help dissipate heat.\nOn the common FR-4 substrates, 1 oz copper per ft2 (35 µm) is the most common thickness; 2 oz (70 µm) and 0.5 oz (17.5 µm) thickness is often an option. Less common are 12 and 105 µm, 9 µm is sometimes available on some substrates. Flexible substrates typically have thinner metalization. Metal-core boards for high power devices commonly use thicker copper; 35 µm is usual but also 140 and 400 µm can be encountered.\nIn the USA, copper foil thickness is specified in units of ounces per square foot (oz/ft2), commonly referred to simply as \"ounce\". Common thicknesses are 1/2 oz/ft2 (150 g/m), 1 oz/ft2 (300 g/m), 2 oz/ft2 (600 g/m), and 3 oz/ft2 (900 g/m). These work out to thicknesses of 17.05 μm (0.67 thou), 34.1 μm (1.34 thou), 68.2 μm (2.68 thou), and 102.3 μm (4.02 thou), respectively.\n1/2 oz/ft2 foil is not widely used as a finished copper weight, but is used for outer layers when plating for through holes will increase the finished copper weight Some PCB manufacturers refer to 1 oz/ft2 copper foil as having a thickness of 35 μm (may also be referred to as 35 μ, 35 micron, or 35 mic).\nConstruction.\nDesign.\nManufacturing starts from the fabrication data generated by computer aided design, and component information. The fabrication data is read into the CAM (Computer Aided Manufacturing) software. CAM performs the following functions:\nInitially PCBs were designed manually by creating a photomask on a clear mylar sheet, usually at two or four times the true size. Starting from the schematic diagram the component pin pads were laid out on the mylar and then traces were routed to connect the pads. Rub-on dry transfers of common component footprints increased efficiency. Traces were made with self-adhesive tape. Pre-printed non-reproducing grids on the mylar assisted in layout. The finished photomask was photolithographically reproduced onto a photoresist coating on the blank copper-clad boards.\nModern PCBs are designed with dedicated layout software, generally in the following steps:\nPanelization.\nSeveral small printed circuit boards can be grouped together for processing as a panel. A panel consisting of a design duplicated \"n\"-times is also called an \"n\"-panel, whereas a \"multi-panel\" combines several different designs onto a single panel. The outer tooling strip often includes tooling holes, a set of panel fiducials, a test coupon, and may include hatched copper pour or similar patterns for even copper distribution over the whole panel in order to avoid bending. The assemblers often mount components on panels rather than single PCBs because this is efficient. Panelization may also be necessary for boards with components placed near an edge of the board because otherwise the board could not be mounted during assembly. Most assembly shops require a free area of at least 10 mm around the board.\nThe panel is eventually broken into individual PCBs along perforations or grooves in the panel through milling or cutting. For milled panels a common distance between the individual boards is 2–3 mm. Today depaneling is often done by lasers which cut the board with no contact. Laser depaneling reduces stress on the fragile circuits, improving the yield of defect-free units.\nCopper patterning.\nThe first step is to replicate the pattern in the fabricator's CAM system on a protective mask on the copper foil PCB layers. Subsequent etching removes the unwanted copper unprotected by the mask. (Alternatively, a conductive ink can be ink-jetted on a blank (non-conductive) board. This technique is also used in the manufacture of hybrid circuits.)\nThe method chosen depends on the number of boards to be produced and the required resolution.\nEtching.\nThe process by which copper traces are applied to the surface is known as \"etching\" after the subtractive method of the process, though there are also additive and semi-additive methods.\nSubtractive methods remove copper from an entirely copper-coated board to leave only the desired copper pattern. The simplest method, used for small-scale production and often by hobbyists, is immersion etching, in which the board is submerged in etching solution such as ferric chloride. Compared with methods used for mass production, the etching time is long. Heat and agitation can be applied to the bath to speed the etching rate. In bubble etching, air is passed through the etchant bath to agitate the solution and speed up etching. Splash etching uses a motor-driven paddle to splash boards with etchant; the process has become commercially obsolete since it is not as fast as spray etching. In spray etching, the etchant solution is distributed over the boards by nozzles, and recirculated by pumps. Adjustment of the nozzle pattern, flow rate, temperature, and etchant composition gives predictable control of etching rates and high production rates. As more copper is consumed from the boards, the etchant becomes saturated and less effective; different etchants have different capacities for copper, with some as high as 150 grams of copper per litre of solution. In commercial use, etchants can be regenerated to restore their activity, and the dissolved copper recovered and sold. Small-scale etching requires attention to disposal of used etchant, which is corrosive and toxic due to its metal content. The etchant removes copper on all surfaces not protected by the resist. \"Undercut\" occurs when etchant attacks the thin edge of copper under the resist; this can reduce conductor widths and cause open-circuits. Careful control of etch time is required to prevent undercut. Where metallic plating is used as a resist, it can \"overhang\" which can cause short-circuits between adjacent traces when closely spaced. Overhang can be removed by wire-brushing the board after etching.\nIn additive methods the pattern is electroplated onto a bare substrate using a complex process. The advantage of the additive method is that less material is needed and less waste is produced. In the full additive process the bare laminate is covered with a photosensitive film which is imaged (exposed to light through a mask and then developed which removes the unexposed film). The exposed areas are sensitized in a chemical bath, usually containing palladium and similar to that used for through hole plating which makes the exposed area capable of bonding metal ions. The laminate is then plated with copper in the sensitized areas. When the mask is stripped, the PCB is finished.\nSemi-additive is the most common process: The unpatterned board has a thin layer of copper already on it. A reverse mask is then applied. (Unlike a subtractive process mask, this mask exposes those parts of the substrate that will eventually become the traces.) Additional copper is then plated onto the board in the unmasked areas; copper may be plated to any desired weight. Tin-lead or other surface platings are then applied. The mask is stripped away and a brief etching step removes the now-exposed bare original copper laminate from the board, isolating the individual traces. Some single-sided boards which have plated-through holes are made in this way. General Electric made consumer radio sets in the late 1960s using additive boards. The (semi-)additive process is commonly used for multi-layer boards as it facilitates the plating-through of the holes to produce conductive vias in the circuit board.\nIndustrial etching is usually done with ammonium persulfate or ferric chloride. For PTH (plated-through holes), additional steps of electroless deposition are done after the holes are drilled, then copper is electroplated to build up the thickness, the boards are screened, and plated with tin/lead. The tin/lead becomes the resist leaving the bare copper to be etched away.\nLamination.\nMulti-layer printed circuit boards have trace layers inside the board. This is achieved by laminating a stack of materials in a press by applying pressure and heat for a period of time. This results in an inseparable one piece product. For example, a four-layer PCB can be fabricated by starting from a two-sided copper-clad laminate, etch the circuitry on both sides, then laminate to the top and bottom pre-preg and copper foil. It is then drilled, plated, and etched again to get traces on top and bottom layers.\nThe inner layers are given a complete machine inspection before lamination because mistakes cannot be corrected afterwards. Automatic optical inspection (AOI) machines compare an image of the board with the digital image generated from the original design data. Automated Optical Shaping (AOS) machines can then add missing copper or remove excess copper using a laser, reducing the number of PCBs that have to be discarded. PCB tracks can have a width of just 10 micrometers.\nDrilling.\nHoles through a PCB are typically drilled with drill bits made of solid coated tungsten carbide. Coated tungsten carbide is used because board materials are abrasive. High-speed-steel bits would dull quickly, tearing the copper and ruining the board. Drilling is done by computer-controlled drilling machines, using a \"drill file\" or Excellon file that describes the location and size of each drilled hole.\nHoles may be made conductive, by electroplating or inserting hollow metal eyelets, to connect board layers. Some conductive holes are intended for the insertion of through-hole-component leads. Others used to connect board layers, are called vias.\nWhen vias with a diameter smaller than 76.2 micrometers are required, drilling with mechanical bits is impossible because of high rates of wear and breakage. In this case, the vias may be laser drilled—evaporated by lasers. Laser-drilled vias typically have an inferior surface finish inside the hole. These holes are called \"micro vias\" and can have diameters as small as 10 micrometers. It is also possible with \"controlled-depth\" drilling, laser drilling, or by pre-drilling the individual sheets of the PCB before lamination, to produce holes that connect only some of the copper layers, rather than passing through the entire board. These holes are called \"blind vias\" when they connect an internal copper layer to an outer layer, or \"buried vias\" when they connect two or more internal copper layers and no outer layers. Laser drilling machines can drill thousands of holes per second and can use either UV or lasers.\nThe hole walls for boards with two or more layers can be made conductive and then electroplated with copper to form \"plated-through holes\". These holes electrically connect the conducting layers of the PCB. For multi-layer boards, those with three layers or more, drilling typically produces a \"smear\" of the high temperature decomposition products of bonding agent in the laminate system. Before the holes can be plated through, this smear must be removed by a chemical \"de-smear\" process, or by \"plasma-etch\". The de-smear process ensures that a good connection is made to the copper layers when the hole is plated through. On high reliability boards a process called etch-back is performed chemically with a potassium permanganate based etchant or plasma etching. The etch-back removes resin and the glass fibers so that the copper layers extend into the hole and as the hole is plated become integral with the deposited copper.\nPlating and coating.\nProper plating or surface finish selection can be critical to process yield, the amount of rework, field failure rate, and reliability.\nPCBs may be plated with solder, tin, or gold over nickel.\nAfter PCBs are etched and then rinsed with water, the solder mask is applied, and then any exposed copper is coated with solder, nickel/gold, or some other anti-corrosion coating.\nMatte solder is usually fused to provide a better bonding surface for bare copper. Treatments, such as benzimidazolethiol, prevent surface oxidation of bare copper. The places to which components will be mounted are typically plated, because untreated bare copper oxidizes quickly, and therefore is not readily solderable. Traditionally, any exposed copper was coated with solder by hot air (solder) levelling (HASL aka HAL). The HASL finish prevents oxidation from the underlying copper, thereby guaranteeing a solderable surface. This solder was a tin-lead alloy, however new solder compounds are now used to achieve compliance with the RoHS directive in the EU, which restricts the use of lead. One of these lead-free compounds is SN100CL, made up of 99.3% tin, 0.7% copper, 0.05% nickel, and a nominal of 60 ppm germanium.\nIt is important to use solder compatible with both the PCB and the parts used. An example is ball grid array (BGA) using tin-lead solder balls for connections losing their balls on bare copper traces or using lead-free solder paste.\nOther platings used are organic solderability preservative (OSP), immersion silver (IAg), immersion tin (ISn), electroless nickel immersion gold (ENIG) coating, electroless nickel electroless palladium immersion gold (ENEPIG), and direct gold plating (over nickel). Edge connectors, placed along one edge of some boards, are often nickel-plated then gold-plated using ENIG. Another coating consideration is rapid diffusion of coating metal into tin solder. Tin forms intermetallics such as Cu6Sn5 and Ag3Cu that dissolve into the Tin liquidus or solidus (at 50 °C), stripping surface coating or leaving voids.\n\"Electrochemical migration\" (ECM) is the growth of conductive metal filaments on or in a printed circuit board (PCB) under the influence of a DC voltage bias. Silver, zinc, and aluminum are known to grow whiskers under the influence of an electric field. Silver also grows conducting surface paths in the presence of halide and other ions, making it a poor choice for electronics use. Tin will grow \"whiskers\" due to tension in the plated surface. Tin-lead or solder plating also grows whiskers, only reduced by reducing the percentage of tin. Reflow to melt solder or tin plate to relieve surface stress lowers whisker incidence. Another coating issue is tin pest, the transformation of tin to a powdery allotrope at low temperature.\nSolder resist application.\nAreas that should not be soldered may be covered with solder resist (solder mask). The solder mask is what gives PCBs their characteristic green color, although it is also available in several other colors, such as red, blue, purple, yellow, black and white. One of the most common solder resists used today is called \"LPI\" (liquid photoimageable solder mask).  A photo-sensitive coating is applied to the surface of the PWB, then exposed to light through the solder mask image film, and finally developed where the unexposed areas are washed away. Dry film solder mask is similar to the dry film used to image the PWB for plating or etching. After being laminated to the PWB surface it is imaged and developed as LPI. Once but no longer commonly used, because of its low accuracy and resolution, is to screen print epoxy ink. In addition to repelling solder, solder resist also provides protection from the environment to the copper that would otherwise be exposed.\nLegend / silkscreen.\nA legend (also known as \"silk\" or \"silkscreen\") is often printed on one or both sides of the PCB. It contains the component designators, switch settings, test points and other indications helpful in assembling, testing, servicing, and sometimes using the circuit board.\nThere are three methods to print the legend:\nBare-board test.\nBoards with no components installed are usually \"bare-board tested\" for \"shorts\" and \"opens\". This is called \"electrical test\" or \"PCB e-test\". A short is a connection between two points that should not be connected. An open is a missing connection between points that should be connected. For high-volume production, a fixture such as a \"bed of nails\" in a rigid needle adapter makes contact with copper lands on the board. The fixture or adapter is a significant fixed cost and this method is only economical for high-volume or high-value production. For small or medium volume production \"flying probe\" testers are used where test probes are moved over the board by an XY drive to make contact with the copper lands. There is no need for a fixture and hence the fixed costs are much lower. The CAM system \"instructs\" the electrical tester to apply a voltage to each contact point as required and to check that this voltage appears on the appropriate contact points and only on these.\nAssembly.\nIn assembly the bare board is populated (or \"stuffed\") with electronic components to form a functional \"printed circuit assembly\" (PCA), sometimes called a \"printed circuit board assembly\" (PCBA). In through-hole technology, the component leads are inserted in holes surrounded by conductive \"pads\"; the holes keep the components in place. In surface-mount technology (SMT), the component is placed on the PCB so that the pins line up with the conductive \"pads\" or \"lands\" on the surfaces of the PCB; solder paste, which was previously applied to the pads, holds the components in place temporarily; if surface-mount components are applied to both sides of the board, the bottom-side components are glued to the board. In both through hole and surface mount, the components are then soldered; once cooled and solidified, the solder holds the components in place permanently and electrically connects them to the board.\nThere are a variety of soldering techniques used to attach components to a PCB. High volume production is usually done with a pick-and-place machine and bulk wave soldering for through-hole parts or reflow ovens for SMT components and/or through-hole parts, but skilled technicians are able to hand-solder very tiny parts (for instance 0201 packages which are 0.02 in. by 0.01 in.) under a microscope, using tweezers and a fine-tip soldering iron, for small volume prototypes. Selective soldering may be used for delicate parts. Some SMT parts cannot be soldered by hand, such as BGA packages. All through-hole components can be hand soldered, making them favored for prototyping where size, weight, and the use of the exact components that would be used in high volume production are not concerns.\nOften, through-hole and surface-mount construction must be combined in a single assembly because some required components are available only in surface-mount packages, while others are available only in through-hole packages. Or, even if all components are available in through-hole packages, it might be desired to take advantage of the size, weight, and cost reductions obtainable by using some available surface-mount devices. Another reason to use both methods is that through-hole mounting can provide needed strength for components likely to endure physical stress (such as connectors that are frequently mated and demated or that connect to cables expected to impart substantial stress to the PCB-and-connector interface), while components that are expected to go untouched will take up less space using surface-mount techniques. \"For further comparison, see the SMT page.\"\nAfter the board has been populated it may be tested in a variety of ways:\nTo facilitate these tests, PCBs may be designed with extra pads to make temporary connections. Sometimes these pads must be isolated with resistors. The in-circuit test may also exercise boundary scan test features of some components. In-circuit test systems may also be used to program nonvolatile memory components on the board.\nIn boundary scan testing, test circuits integrated into various ICs on the board form temporary connections between the PCB traces to test that the ICs are mounted correctly. Boundary scan testing requires that all the ICs to be tested use a standard test configuration procedure, the most common one being the Joint Test Action Group (JTAG) standard. The JTAG test architecture provides a means to test interconnects between integrated circuits on a board without using physical test probes, by using circuitry in the ICs to employ the IC pins themselves as test probes. JTAG tool vendors provide various types of stimuli and sophisticated algorithms, not only to detect the failing nets, but also to isolate the faults to specific nets, devices, and pins.\nWhen boards fail the test, technicians may desolder and replace failed components, a task known as \"rework\".\nProtection and packaging.\nPCBs intended for extreme environments often have a conformal coating, which is applied by dipping or spraying after the components have been soldered. The coat prevents corrosion and leakage currents or shorting due to condensation. The earliest conformal coats were wax; modern conformal coats are usually dips of dilute solutions of silicone rubber, polyurethane, acrylic, or epoxy. Another technique for applying a conformal coating is for plastic to be sputtered onto the PCB in a vacuum chamber. The chief disadvantage of conformal coatings is that servicing of the board is rendered extremely difficult.\nMany assembled PCBs are static sensitive, and therefore they must be placed in antistatic bags during transport. When handling these boards, the user must be grounded (earthed). Improper handling techniques might transmit an accumulated static charge through the board, damaging or destroying components. The damage might not immediately affect function but might lead to early failure later on, cause intermittent operating faults, or cause a narrowing of the range of environmental and electrical conditions under which the board functions properly. Even bare boards are sometimes static sensitive: traces have become so fine that it is possible to blow a trace (or change its characteristics) with a static discharge. This is especially true on non-traditional PCBs such as MCMs and microwave PCBs.\nCordwood construction.\nCordwood construction can save significant space and was often used with wire-ended components in applications where space was at a premium (such as fuzes, missile guidance, and telemetry systems) and in high-speed computers, where short traces were important. In cordwood construction, axial-leaded components were mounted between two parallel planes. The name comes from the way axial-lead components (capacitors, resistors, coils, and diodes) are stacked in parallel rows and columns, like a stack of firewood. The components were either soldered together with jumper wire or they were connected to other components by thin nickel ribbon welded at right angles onto the component leads. To avoid shorting together different interconnection layers, thin insulating cards were placed between them. Perforations or holes in the cards allowed component leads to project through to the next interconnection layer. One disadvantage of this system was that special nickel-leaded components had to be used to allow reliable interconnecting welds to be made. Differential thermal expansion of the component could put pressure on the leads of the components and the PCB traces and cause mechanical damage (as was seen in several modules on the Apollo program). Additionally, components located in the interior are difficult to replace. Some versions of cordwood construction used soldered single-sided PCBs as the interconnection method (as pictured), allowing the use of normal-leaded components at the cost of being difficult to remove the boards or replace any component that is not at the edge.\nBefore the advent of integrated circuits, this method allowed the highest possible component packing density; because of this, it was used by a number of computer vendors including Control Data Corporation. The cordwood method of construction was used only rarely once PCBs became widespread, mainly in aerospace or other extremely high-density electronics.\nTypes.\nBreakout boards.\nA minimal PCB for a single component, used for prototyping, is called a breakout board. The purpose of a breakout board is to \"break out\" the leads of a component on separate terminals so that manual connections to them can be made easily. Breakout boards are especially used for surface-mount components or any components with fine lead pitch.\nAdvanced PCBs may contain components embedded in the substrate, such as capacitors and integrated circuits, to reduce the amount of space taken up by components on the surface of the PCB while improving electrical characteristics.\nMultiwire boards.\nMultiwire is a patented technique of interconnection which uses machine-routed insulated wires embedded in a non-conducting matrix (often plastic resin). It was used during the 1980s and 1990s. As of 2010, Multiwire was still available through Hitachi.\nSince it was quite easy to stack interconnections (wires) inside the embedding matrix, the approach allowed designers to forget completely about the routing of wires (usually a time-consuming operation of PCB design): Anywhere the designer needs a connection, the machine will draw a wire in a straight line from one location/pin to another. This led to very short design times (no complex algorithms to use even for high density designs) as well as reduced crosstalk (which is worse when wires run parallel to each other—which almost never happens in Multiwire), though the cost is too high to compete with cheaper PCB technologies when large quantities are needed.\nCorrections can be made to a Multiwire board layout more easily than to a PCB layout.\nUses.\nPrinted circuit boards have been used as an alternative to their typical use for electronic and biomedical engineering thanks to the versatility of their layers, especially the copper layer. PCB layers have been used to fabricate sensors, such as capacitive pressure sensors and accelerometers, actuators such as microvalves and microheaters, as well as platforms of sensors and actuators for Lab-on-a-chip (LoC), for example to perform polymerase chain reaction (PCR), and fuel cells, to name a few.\nRepair.\nManufacturers may not support component-level repair of printed circuit boards because of the relatively low cost to replace compared with the time and cost of troubleshooting to a component level. In board-level repair, the technician identifies the board (PCA) on which the fault resides and replaces it. This shift is economically efficient from a manufacturer's point of view but is also materially wasteful, as a circuit board with hundreds of functional components may be discarded and replaced due to the failure of one minor and inexpensive part, such as a resistor or capacitor. This practice is a significant contributor to the problem of e-waste.\nLegislation.\nIn many countries (including all European Single Market participants, the United Kingdom, Turkey, and China), legislation restricts the use of lead, cadmium and mercury in electrical equipment. PCBs sold in such countries must therefore use lead-free manufacturing processes and lead-free solder, and attached components must themselves be compliant.\nSafety Standard UL 796 covers component safety requirements for printed wiring boards for use as components in devices or appliances. Testing analyzes characteristics such as flammability, maximum operating temperature, electrical tracking, heat deflection, and direct support of live electrical parts.", "Engineering,_Manufacturing": 0.9999046326, "qwen": "Yes"}
{"id": "23253056", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=23253056", "title": "International Metalworking Companies", "text": "IMC International Metalworking Companies B.V., otherwise known as IMC Group, is the holding company of several worldwide manufacturers of metal cutting tools. Together they produces a wide range of carbide inserts, carbide endmills and cutting tools covering all metal cutting applications. The IMC Group is in the automotive, aerospace, die and mold, general engineering, bearing manufacturing and energy industries.\nSubsidiaries.\nToday, the IMC Group has over 130 subsidiaries in 65 countries.\nPrimary Subsidiaries:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1572578", "revid": "1127019274", "url": "https://en.wikipedia.org/wiki?curid=1572578", "title": "6-8-6", "text": "Under the Whyte notation for the classification of steam locomotives by wheel arrangement, represents the arrangement of six unpowered leading wheels arranged into a three-axle leading truck, eight powered driving wheels, and six unpowered trailing wheels arranged into a three-axle trailing truck.\nOther equivalent classifications are:\nThe only known example of the 6-8-6 wheel arrangement is the experimental Pennsylvania Railroad S2 steam turbine locomotive.", "Engineering,_Manufacturing": 0.9996954203, "qwen": "Yes"}
{"id": "50816133", "revid": "1161982125", "url": "https://en.wikipedia.org/wiki?curid=50816133", "title": "Huhtamaki PPL", "text": "Huhtamaki PPL Limited or HPPL (formerly: The Paper Products Limited) is an Indian multinational company specializing in flexible packaging and packaging solutions, founded in 1935 in Lahore. In 1999, the company became part of Huhtamäki Oyj, Finland. It has been involved in the field of packaging for over 80 years.\nThe company has its registered office in Mumbai, India; and as of 2016, has 14 manufacturing locations across India and sales offices in Mumbai, Delhi, Bangalore and Kolkata.\nThe company manufactures flexible laminates, films, specialized pouches, cartons, tube laminates, labels, shrink sleeves, rotogravure cylinders, packaging machinery etc. It caters to customers across sectors ranging from food and beverages, personal care to pharmaceuticals, industrial products etc.\nHistory.\nThe company was founded in 1935 as ‘The Paper Products Limited’ by Mr. Sardarilal Talwar. The company’s first assignment was converting paper into paper products for the British Army Dairy, thus starting flexible packaging.\nIn the 1960s, the company moved from manufacturing packaging products using paper to using cellophane-based products for bread and biscuit packs, along with twist wraps.\nIn the 1980s, it started polymer-based packaging and created material for commercial use in the form of flexible packaging.\nProducts.\nThe company offers solutions such as Flexible Packaging, Specialised Pouches, Thermoforms, Shrink Sleeve Solutions, Decorative Packaging, Value added cartons and Security Solutions and Promotions.\nAwards.\nHPPL has received several awards (as The Paper Products Ltd); recent ones being:\nParent company.\nHuhtamaki, headquartered in Espoo, Finland is a global packaging manufacturer and supplier for various applications. Its primary outputs include cartons and containers for foods and other consumer goods, disposable tableware and films and laminates for uses such as adhesives, plasters and labels.\nIt has 71 manufacturing units in 34 countries and a support staff of 15,800 globally. Its net sales in 2015 were approximately €2.7 billion.", "Engineering,_Manufacturing": 0.9996562004, "qwen": "Yes"}
{"id": "9814132", "revid": "12959150", "url": "https://en.wikipedia.org/wiki?curid=9814132", "title": "CheckInstall", "text": "CheckInstall is a computer program for Unix-like operating systems which eases the installation and uninstallation of software compiled from source by making use of package management systems. After software compilation it can automatically generate a Slackware-, RPM-, or Debian-compatible package that can later be cleanly uninstalled through the appropriate package manager.\nCheckInstall monitors the installation phase of a normal software build process and notes the files that are added to the system. It then builds a package that contains these files, using additional information gathered from the user. Finally, the files installed by the original run are removed and the package is installed using the system package tools, so the package will be properly registered in the local installed packages database.\nThe primary benefits provided by CheckInstall versus simply running codice_1 are the ability to remove the package from the system using the system packaging tools, and the ability to install the resulting package on multiple machines. CheckInstall is sometimes cited as a mechanism for creating packages by open source projects instead of creating numerous platform-specific build packages.\nUsage.\nCheckinstall is usually used after running a configure script and codice_2, as follows:\n ./configure\n make\n sudo checkinstall\nAfter entering some information about the author and a package description, you will get the folder where the generated package has been saved to.", "Engineering,_Manufacturing": 0.999774754, "qwen": "Yes"}
{"id": "9833385", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=9833385", "title": "Butt welding", "text": "Butt welding is when two pieces of metal are placed end-to-end without overlap and then welded along the joint (as opposed to lap joint weld, where one piece of metal is laid on top of the other, or plug welding, where one piece of metal is inserted into the other). Importantly, in a butt joint, the surfaces of the workpieces being joined are on the same plane and the weld metal remains within the planes of the surfaces.\nCommon uses.\nButt welding is a commonly used technique in welding that can either be automated or done by hand on steel pieces. Butt welding can also be done with brazing for copper pieces. It is used to attach two pieces of metal together such as pipe, framework in factories, and also flanges. A flange is something that either is internal or external that provided to strengthen a piece of material. In factories butt welding has shown how economical it can be for companies to use when building things out of metal. This is because if they wanted to make something out of metal without welding it together they would have to bend everything and reinforce the structure which costs more than welding the two pieces together. Butt welding is accomplished by heating up two pieces of metal, or applying pressure, or doing both of those. Penetration while welding the metal is important to maintain and with thin pieces of metal this is possible however, with thick pieces edge preparation may have to be done to prepare the metal. Full penetration butt welds are made when they are in the within the parent(bigger, stronger) metal. In butt welding the strongest welds will have the fewest imperfections. To achieve this the heat input is controlled, which decreases the size of the weld. In commercial welding when this is done it also reduces cost but in order to maintain the strength of the weld double butt welds will be used. In butt welding there are two types used to achieve the specific welds and then there are also a variety of joints considered to be butt joints.\nButt welding is best performed with MIG or TIG welding applications due to their natural ability to connect two pieces of metal together. Using different types of welding electrodes for the welder will determine the properties of the weld such as its resistance against corrosion and strength. Electrodes conduct current through the metal being welded in order join the two pieces. The metal determines the type of welding that is required. The electrodes are either heavily or lightly coated. For the heavily coated electrodes are commonly used in structural welding because they are much stronger and corrosion resistant. The lightly coated electrodes are not as structurally sound. Butt welding is performed with the Arc, TIG, or MIG welder held at a slight angle the weld if the weld is laying flat in order to achieve the least amount of porosity in the weld and also to increase the weld's strength. Fillet welding make up about 80 percent of the connection despite being weaker than butt welds. The reason it is used more often is because fillet welds offer more room for error with much larger tolerances. Fillet welding is not a type of butt weld despite its similarities.\nTypes of butt welding.\nFlash.\nFlash butt welding is used with machinery and connects multiple pieces of metal together that are miss matched in size and shape. These different sizings can oftentimes cause for breaks in welding process. High voltage current is applied in order to connect the metal pieces together by applying it to both the components known as flashing in order to join them together.\nResistance.\nThis weld joins the two pieces of metal together by heat that comes from the pressure due to the metals being held together at a preset force. Resistance butt welding is used on joints that are of similar shape and size and often the weld is performed in one movement unlike flash welding.\nTypes of butt joints.\nThere are many different types of butt welding joints and they all are named with their particular shape. The joint also known as a square groove weld has many different forms in order to connect pieces of metal together and are all capable of bearing loads. There are many different types of joints such as lap joints, tee joints, butt joints, and also corner joints. Lap joints are two pieces that are end-over-end and welded together whereas butt welds are put end to end and connected that way. Butt welds are connected to each other with the thickness of the parent metal. There are many different kinds of butt welds such as square, single v, double v, single bevel, double bevel, single u, double u, single j, and also a double j. Minimizing the distortions in a weld is important however doing so will minimize the chances of full penetration. In order to get full penetration double welds such as double v, double j, and double u may be used.\nStandards.\nEN 1993-1-8, which covers the design of joints in the design of steel structures, defines a set of provisions for welding structural steel.", "Engineering,_Manufacturing": 0.999992609, "qwen": "Yes"}
{"id": "4343134", "revid": "46239567", "url": "https://en.wikipedia.org/wiki?curid=4343134", "title": "1973–74 European Cup Winners' Cup", "text": "The 1973–74 European Cup Winners' Cup football club tournament was won by Magdeburg in a final victory against defending champions Milan. It was the first–and only–win for an East German side in a European tournament.\nFirst round.\nAlbania refused to play.\nSecond leg.\n\"Sunderland won 3-0 on aggregate.\"\n\"Sporting CP won 2-1 on aggregate.\"\n\"3-3 on aggregate, Zürich won on away goals.\"\n\"Malmö won 11-0 on aggregate.\"\n\"Magdeburg won 2-0 on aggregate.\"\n\"Baník Ostrava won 3-1 on aggregate.\"\n\"Beroe Stara Zagora won 11-1 on aggregate.\"\n\"Athletic Bilbao won 2-0 on aggregate.\"\n\"AC Milan won 4-1 on aggregate.\"\n\"Rapid Wien won 2-1 on aggregate.\"\n\"Lyon won 2-0 on aggregate.\"\n\"PAOK won 2-1 on aggregate.\"\n\"SK Brann won 9-0 on aggregate.\"\n\"Glentoran won 4-2 on aggregate.\"\n\"Borussia Mönchengladbach won 16-1 on aggregate.\"\n\"Rangers won 6-0 on aggregate.\"\nSecond round.\nSecond leg.\n\"Sporting CP won 3-2 on aggregate.\"\n\"1-1 on aggregate, Zürich won on away goals.\"\n\"Magdeburg won 3-2 on aggregate.\"\n\"Beroe Stara Zagora won 3-1 on aggregate.\"\n\"AC Milan won 2-0 on aggregate.\"\n\"PAOK won 7-3 on aggregate.\"\n\"Glentoran won 4-2 on aggregate.\"\n\"Borussia Mönchengladbach won 5-3 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"Sporting CP won 4-1 on aggregate.\"\n\"Magdeburg won 3-1 on aggregate.\"\n\"Milan won 5-2 on aggregate.\"\n\"Borussia Mönchengladbach won 7-0 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Magdeburg won 3-2 on aggregate.\"\n\"Milan won 2-1 on aggregate.\"", "Engineering,_Manufacturing": 1.0000047684, "qwen": "Yes"}
{"id": "4343425", "revid": "28342191", "url": "https://en.wikipedia.org/wiki?curid=4343425", "title": "Rochester Midland Corporation", "text": "Rochester Midland Corporation is a closely-held specialty chemical manufacturing company headquartered in Ogden, New York. It has sales and operations in nearly seventy countries, production facilities in Ogden, New York, Aurora, Illinois. It was founded as Rochester Germicide in 1888.", "Engineering,_Manufacturing": 0.9988980889, "qwen": "Yes"}
{"id": "46634117", "revid": "40103922", "url": "https://en.wikipedia.org/wiki?curid=46634117", "title": "Apple chip", "text": "Apple chips are chips or crisps that are prepared using apple. When stale, apple chips become drier and crispier. Contrary to modern belief, apple chips do not become chewier when stale, only harder. Apple chips may be fried, deep fried, vacuum fried, dehydrated or baked. Apple chips may have a dense and crispy texture, or may be puffed, yet still crispy. Microwave vacuum-drying may be used to prepare apple chips with a puffy and crispy texture. They may be seasoned with cinnamon and sweetened with confectioners sugar. Apple chips may be consumed as a snack food, and may be accompanied with various dips and other foods. Apple chips are mass-produced in the United States.\nUse in dishes.\nApple chips may be used in sandwiches and as an ingredient in desserts and sweets, such as cookies. They may also be used as a garnish on dishes.\nManufacturers.\nApple chips are mass-produced by some food manufacturers. Companies that produce them include Seneca Foods, Bare Fruit, Buddy Fruits and Tyrrell's Bare Fruit and Buddy Fruits apple chips are prepared using only apples as their sole ingredient.", "Engineering,_Manufacturing": 0.9988687038, "qwen": "Yes"}
{"id": "40043829", "revid": "1168683332", "url": "https://en.wikipedia.org/wiki?curid=40043829", "title": "List of Hyundai transmissions", "text": "Hyundai Transys is an affiliate company of Hyundai Motor Group and produces a number of automobile transmissions, axles and seats in-house.\nOn January 1, 2019, Hyundai DYMOS and Hyundai Powertech were merged with Hyundai Transys.\nHyundai Powertech was established in 2001 as South Korea's first automatic transmission specialist. It has plants in South Korea, China, and the United States. Its automatic transmissions are used in Hyundai, Kia, Dodge, and Jeep vehicles.\nHyundai DYMOS produces MT based transmissions including DCT and AMT along with axles, 4WD and seats as automotive parts.\nAutomatic Transmission (AT).\nFront wheel.\n4-speed automatic.\nA4F12/A4CF0.\nRated up to while having a dry weight of .\nA4F16/A4CF1.\nRated up to while having a dry weight of .\nA4F23/A4CF2.\nRated up to while having a dry weight of .\n5-speed automatic.\nA5F16.\nRated up to while having a dry weight of .\nA5F23/A5GF1.\nRated up to while having a dry weight of .\nA5HF1.\nRated up to \n6-speed automatic.\nA6F17.\nRated up to while having a dry weight of .\nA6F18.\nRated up to while having a dry weight of .\nA6F22/A6GF1.\nRated up to while having a dry weight of .\nA6F24/A6MF1.\nRated up to while having a dry weight of . It is contracted by Chrysler Group LLC for use in 2013–2016 Dodge Dart and 2014-2016 Jeep Compass and Jeep Patriot, the transmission is designed to be maintenance-free under normal use and is assembled in South Korea.\nA6F27/A6MF2.\nRated up to while having a dry weight of .\nA6F28H/A6FMH/A6MF2H.\nFor Hybrid applications, rated up to while having a dry weight of .\nA6F30.\nRated up to while having a dry weight of .\nA6F33/A6LF1.\nRated up to while having a dry weight of .\nA6F36/A6LF2.\nRated up to while having a dry weight of .\nA6LF3.\nRated up to .\n8-speed automatic.\nA8F27/A8MF1.\nRated up to while having a dry weight of .\nA8F36/A8LF1.\nRated up to while having a dry weight of .\nA8F42/A8LF2.\nRated up to while having a dry weight of .\nA8FLH.\nFor Hybrid applications, rated up to (motor only) or total output.\nRear wheel.\n5-speed automatic.\nA5R25.\nRated up to while having a dry weight of .\nA5R35/A5SR1.\nRated up to while having a dry weight of .\nA5R45/A5SR2.\nRated up to while having a dry weight of .\n8-speed automatic.\nA8R40/A8LR1.\nRated up to while having a dry weight of .\nA8R50/A8TR1.\nRated up to while having a dry weight of .\nContinuously Variable Transmission (CVT).\nKappa CVT.\nRated up to or , supports idle stop and go functions.\nGamma CVT CF18/C0GF1.\nRated up to , supports idle stop and go functions.\nCF28.\nRated up to .\nDual Clutch Transmission (DCT).\n6-speed dual clutch.\nD6GF1.\nRated up to while having a dry weight of . This transmission uses dry clutch.\nD6KF1/D6F27H.\nFor Hybrid applications, rated up to while having a dry weight of . This transmission uses dry clutch.\n7-speed dual clutch.\nD7GF1/D7F22.\nRated up to while having a dry weight of . This transmission uses dry clutch.\nD7UF1/D7F34.\nRated up to while having a dry weight of . This transmission uses dry clutch.\n8-speed dual clutch.\nD8LF1/D8F48W.\nRated up to . This transmission uses wet clutch.\nAutomated Manual Transmission (AMT).\n5-Speed AMT.\nS5F13.\nRated up to .\nManual Transmission (MT).\nFront Wheel.\n5-speed manual.\nM5EF2/M5F13.\nRated up to while having a dry weight of \nM5AF3/M5F14.\nRated up to while having a dry weight of \nM5CF1/M5F16.\nRated up to while having a dry weight of \nM5BF2/M5CF2/M5F19.\nRated up to while having a dry weight of \nM5GF1/M5F25.\nRated up to while having a dry weight of \nM5GF2.\nRated up to \nM5HF2.\nRated up to \n6-speed manual.\nM6CF1/M6F17.\nRated up to while having a dry weight of \nM6CF3/M6F28-1.\nRated up to while having a dry weight of \nM6CF4/M6F28-2.\nRated up to while having a dry weight of \nM6LF1/M6F44.\nRated up to while having a dry weight of \nRear Wheel.\n5-speed manual.\nM5R18.\nRated up to while having a dry weight of \nM5R23.\nRated up to while having a dry weight of \nM5R26.\nRated up to while having a dry weight of \nM5R32.\nRated up to while having a dry weight of \nM5R36.\nRated up to while having a dry weight of \n6-speed manual.\nM6R26.\nRated up to while having a dry weight of \nM6R34.\nRated up to while having a dry weight of \nM6R37.\nRated up to while having a dry weight of \nM6R40.\nRated up to .\nReduction Gear.\nShift by Cable (SBC).\nG1F24.\nRated up to while having a dry weight of , its used in the Kia Ray EV\nG1F30.\nRated up to while having a wet weight of , its used in the Hyundai Avante EV, Kia KX3 EV and Kia Soul EV.\nG1F36.\nRated up to while having a wet weight of , its used in the Tucson Fuel Cell EV.\nShift by Wire (SBW).\nG1F24.\nRated up to while having a wet weight of , its used in the Hyundai Ioniq EV.\nG1F26.\nRated up to while having a wet weight of , its used in the Hyundai Nexo, Hyundai Kona EV (OS), Kia Niro EV and Kia Soul EV.\nG1F32.\nRated up to while having a wet weight of .", "Engineering,_Manufacturing": 0.9997124076, "qwen": "Yes"}
{"id": "40046610", "revid": "525927", "url": "https://en.wikipedia.org/wiki?curid=40046610", "title": "Semiembossed film", "text": "Semiembossed film is used as a liner to the calendared rubber to retain the properties of rubber and also to prevent dust and other foreign matters from sticking to the rubber while calendaring and during storage. It is manufactured with 100% virgin low-density polyethylene. The raw material is extruded and cast on the embossed roll and cooled. It can be of any color. Milky white, French blue, red and yellow are standard colors. The diamond-shaped embossing in the film helps in the easy removal of air between the film and the rubber. Semiembossed film is used by tyre manufacturers, tread and bonding gum manufacturers, conveyor belt manufacturers and other rubber coated fabric manufacturers.\nFilm embossing process.\nFilm embossing is a mechanical process in which a flat film is transformed into an embossed product. During the process, thermal and stress fields are applied to the polymer, causing changes in the microstructure and physical dimensions of the material. The engineering analysis of the process requires the study of various aspects relating to the characterization of the microstructure before and after embossing, A variety of techniques were employed to characterize the properties and microstructure of the embossed film in relation to crystallinity, orientation, mechanical properties, and dimensions of the embossed films. The thermal treatment of the polymer film was shown to be the most significant factor in the process. By controlling the thermal treatment of the film, it is possible to manipulate the properties and dimensions of the embossed film. The important aspects: influencing thermal treatment include the radiation heater temperature, preheat roll temperature, line velocity, and film thickness. The initial film orientation and embossing pressure have a minor effect on the final properties of the embossed film. The main effect of the embossing pressure is on the bulk thickness of the embossed film.", "Engineering,_Manufacturing": 0.9994429946, "qwen": "Yes"}
{"id": "40047107", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=40047107", "title": "Shut-off nozzle", "text": "Shut-off nozzles are used in the manufacturing process of plastic injection molding. Machine shut-off nozzles serve as the connection between the plasticizing barrel (with reciprocating screw) and the mold. They are mounted on the machineside of the plastic injection molding process, unlike hot runner nozzles which are mounted on the moldside of the process. Machine shut-off nozzles differ from open nozzles because of their closable melt channel.\nReasons for using.\nShut-off nozzles are used to avoid drooling of the melt and stringing, as well as to feed with a retracted nozzle.\nTypes.\nShut-off nozzles can be self-controlled or externally controlled.\nSelf-controlled.\nThe needle keeps the nozzle orifice closed by spring pressure. When the injection pressure increases, the melt will push back on the needle head and try to open the nozzle. Once the melt inside the nozzle reaches a certain amount of pressure, it will succeed in pushing the needle back against the spring. There must, therefore, be a minimum pressure for the opening process to overcome the force of the spring. Once the nozzle opens, the pressure will drop again and the spring-operated needle will close the nozzle tip orifice.\nExternally actuated.\nThe nozzle is opened by external force, independent of the melt-pressure. The shut-off nozzle’s actuation is hydraulically or pneumatically driven. Externally actuated shut-off nozzles can have different ways of closing the melt stream. Due to the fact that they operate independently of melt-pressure, they can be used for a range of applications such as melt pre-compression, physical and chemical foaming and high-speed injection molding.\nNeedle.\nThe melt flow is shut off via a melt channel-axis positioned needle moving back and forth according to actuation. This nozzle type shuts off the melt stream directly at the nozzle orifice-mold interface which prevents drooling.\nBolt.\nA shut-off bolt, positioned perpendicular to the melt channel moves up and down according to actuation, and thus shuts off/opens the melt flow. This nozzle type has a single melt channel. It therefore does not require rerouting of the melt around the shut-off mechanism. This makes it more suitable for processing of large volumes as well as shear sensitive materials.\nRotary.\nThis nozzle type is fitted with a rotatable bolt assembly which has a cavity equal in size to the melt channel. In its open position, the bolt cavity is directly aligned with the melt stream. When the actuator rotates the bolt assembly, the cavity becomes misaligned and thus shuts off the melt flow.", "Engineering,_Manufacturing": 0.9999969006, "qwen": "Yes"}
{"id": "40056708", "revid": "46388047", "url": "https://en.wikipedia.org/wiki?curid=40056708", "title": "Self-lubricating chain", "text": "Self-lubricating chains, also referred to as lube-free chains, are commonly found in both roller chain (ANSI Standards, British Standards, and DIN Standards) and conveyor chain varieties, with specialty self-lubricating chains also available. These chains utilize a bush made of an oil-impregnated sintered metal or plastic to provide continuous lubrication to the chain during drive, eliminating the need for further lubrication.\nHistory.\nWhile some of the earliest self-lubricating bearings were developed by Chrysler the earliest self-lubricating chains were bushed chains, which consisted of pins, plates, and sintered bushes. The loss in strength of the bush required it to be made extra thick. This made the outer diameter so large that it did not allow enough room for a roller. These bushed chains suffer from the drawback of lower allowable load and tensile strength compared to regular roller chain, and the outer diameter of the bushes do not rotate when engaging a sprocket and may suffer faster wear and damage. \nWhile various chain manufacturers offered self-lubricating bushed chain designs based on sintered-bush technology since the 1950s, the world's first self-lubricating roller chain was developed and launched by a Japanese chain manufacturer in 1988. After they made further improvements to the oil impregnation and sintering technologies, they received a patent for their lube-free roller chain, as evidenced by Patent #JP20070237969. In the new design, advancements in powder metal bush technology allowed engineers to design a bush that had a smaller diameter yet was stronger, which allowed room for rollers. These rollers improved performance by allowing the chain to articulate more smoothly into sprockets and protect the sintered bushes. Because of these advancements, the self-lubrication style chains achieved strength on par with regular roller chain, with the added benefit of being lube-free. \nPowdered metal sintered bearings (in the case of roller chain, the bushes) are self-lubricating because their porosity is impregnated with lubricants during the manufacturing process. In use, frictional heat causes the lubricant to expand and flow out of the pores, forming a film between mating parts. Low coefficients of friction, minimal maintenance and trouble-free service life, low cost, and simple installation are the chief advantages of powdered metal bearings.\nConstruction.\nAs with standard roller chains, self-lubricating roller chains consist of five basic parts: inner plates, outer plates, pins, bushes, and rollers. However, the bushes for self-lubricating chains are sintered metal, produced using powder metallurgy. Self-lubricating chains can be manufactured cheaply, quickly, and to precision tolerances. To form the bushings, alloyed powdered metal is mixed, compacted, and sintered. The initial compaction to a large degree dictates the density, shape, dimensions, and mechanical properties of the finished part. Sintered materials have inherent porosity, and the pores have both beneficial and detrimental effects on part performance. The pores act as stress concentration zones and reduce mechanical strength and ductility. However, the pores also reduce noise and vibration and serve as lubricant pockets in lubricated contacts. Sintered bearings and gears are used in many applications where the external lubrication is not possible or not preferred. It is essential that the pores form an interconnected system of controlled size and volume, so that oil is supplied to the entire bearing surface. The rate of oil supply increases with temperature and therefore with increasing speeds of rotation, improving performance.\nApplications.\nSelf-lubrication is ideal in situations where normal lubrication is difficult, troublesome, or impossible. For example, in paper and food processing, lubrication is undesirable due to product contamination. (Chain companies like Tsubaki, Nishiyama and Renold PLC also offer sintered bushes impregnated with food grade lubricant.)\nSelf-lubricating bushes are used in conveyor chains as well as roller chains for a variety of conveyance applications. These could include not only RS attachment roller chain, but small size conveyor chains and a wide variety of top chains as well.", "Engineering,_Manufacturing": 1.0000060797, "qwen": "Yes"}
{"id": "21438345", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=21438345", "title": "Design knowledge", "text": "There is a large body of knowledge that designers call upon and use during the design process to match the ever-increasing complexity of design problems. Design knowledge can be classified into two categories: product knowledge and design process knowledge.\nProduct Knowledge.\nProduct knowledge has been fairly studied and a number of modeling techniques have been developed. Most of them are tailored to specific products or specific aspects of the design activities. For example, geometric modeling is used mainly for supporting detailed design, while knowledge modeling is working for supporting conceptual designs. Based on these techniques, a design repository project at NIST attempts to model three fundamental facets of an artifact representation: the physical layout of the artifact (form), an indication of the overall effect that the artifact creates (function), and a causal account of the operation of the artifact (behavior). The recent NIST research effort towards the development of the basic foundations of the next generation of CAD systems suggested a core representation for design information called the NIST core product model (CPM) and a set of derived models defined as extensions of the CPM (e.g.). The NIST core product model has been developed to unify and integrate product or assembly information. The CPM\nprovides a base-level product model that is: not tied to any vendor software; open; non-proprietary; expandable; independent of any one product development process; capable of capturing the engineering context that is most commonly shared in product development activities. The core model focuses on artifact representation including function, form, behavior, material, physical and functional decompositions, and relationships among these concepts. The entity-relationship data model influences the model heavily; accordingly, it consists of two sets of classes, called object and relationship, equivalent to the UML class and association class, respectively.\nDesign Process Knowledge.\nDesign process knowledge can be described in two levels: design activities and design rationale. The importance of representation for design rationale has been recognized but it is a more complex issue that extends beyond artifact function. The design structure matrix (DSM) has been used for modeling design process (activities) and some related research efforts have been conducted. For example, a web-based prototype system for modeling the product development process using a multi-tiered DSM is developed at MIT. However, few research endeavors have been found on design rationale.\nRepresentation Scenarios.\nIn terms of representation scenarios, design knowledge can also be categorized into off-line and on-line knowledge. Design process knowledge can be categorized into ontologies.\nOff-line Knowledge.\nOffline Knowledge refers to existing knowledge representation, including design knowledge in handbook and design ‘‘know-how’’, etc.; the latter refers to the new design knowledge created in the course of design activities by designers themselves. For the off-line knowledge, there are two representation approaches. One is to highly abstract and categorize existing knowledge including experiences into a series of design principles, rationales and constraints. TRIZ is a good instance of this approach. The other is to represent a collection of design knowledge into a certain case for description. Case-based design is an example of this approach. The key issue is on the computerization of the\ndesign knowledge representation. For instance, researchers at the Engineering Design Centre at Lancaster University, UK established a unique knowledge representation methodology and knowledge base vocabulary based on the theory of domains, design principles and computer modeling. They developed a software tool for engineering knowledge management. The tool provides an engineering system designer with the capability to search a knowledge base of past solutions, and other known technologies to explored viable alternatives for product design.\nOn-line Knowledge.\nOn-line knowledge representation is capturing the dynamic design knowledge in a certain format for design re-use and archive. A few research efforts have been found in this area. Blessing proposes the process-based support system (PROSUS) based on a model of the design process rather than the product. It uses a design matrix to represent the design process as a structured set of issues and activities. Together with the common product data model (CPDM), PROSUS supports the capture of all outputs of the design activity.\nOntologies.\nOntologies are being used for product representation (e.g.). Research suggests that there is a need to provide computer support that will supply clear and complete design knowledge and also facilitate designer intervention and customization during the decision-making activities in the design process. For example, WebCADET is a design support system that uses distributed Web-based AI tools. It uses the AI as text approach, where knowledge-based systems (KBSs) can be seen as a medium to facilitate the communication of design knowledge between designers. The system can provide support for designers when searching for design knowledge.", "Engineering,_Manufacturing": 0.9994050264, "qwen": "Yes"}
{"id": "21464260", "revid": "1164178366", "url": "https://en.wikipedia.org/wiki?curid=21464260", "title": "Jump rings", "text": "Jump rings are (usually metal) rings used to make chains, jewellery and chain mail. They are made by wrapping wire around a mandrel to make a coil, then cutting the coil with wire cutters to make individual rings. The rings can be assembled one by one into chains, earrings, objects such as bowls or ornaments, and chain mail clothing.\nThe making of items from jump rings is called \"chain maille\" (\"\"maille\" is French for \"mesh\"\"). \nJump rings can be described by the following qualities:", "Engineering,_Manufacturing": 0.9981261492, "qwen": "Yes"}
{"id": "6086634", "revid": "24880950", "url": "https://en.wikipedia.org/wiki?curid=6086634", "title": "Planer (metalworking)", "text": "A planer is a type of metalworking machine tool that uses linear relative motion between the workpiece and a single-point cutting tool to cut the work piece. A planer is similar to a shaper, but larger, and with workpiece moving, whereas in a shaper the cutting tool moves.\nApplications.\nLinear planing.\nThe most common applications of planers and shapers are linear-toolpath ones, such as: \nHelical planing.\nAlthough the archetypal toolpath of a planer is linear, helical cutting can be accomplished by coupling the table's linear motion to simultaneous rotation. The helical planing idea is similar to both helical milling and single-point screw cutting.\nCurrent Usage.\nPlaners and shapers are now obsolescent, because other machine tools (such as milling machines, broaching machines, and grinding machines) have mostly eclipsed them as the tools of choice for doing such work. However, they have not yet disappeared from the metalworking world. Planers are used by smaller tool and die shops within larger production facilities to maintain and repair large stamping dies and plastic injection molds. Additional uses include any other task where an abnormally large (usually in the range of 4'×8' or more) block of metal must be squared when a (quite massive) horizontal grinder or floor mill is unavailable, too expensive, or otherwise impractical in a given situation. As usual in the selection of machine tools, an old machine that is in hand, still works, and is long since paid-for has substantial cost advantage over a newer machine that would need to be purchased. This principle easily explains why \"old-fashioned\" techniques often have a long period of gradual obsolescence in industrial contexts, rather than a sharp drop-off of prevalence such as is seen in mass-consumer technology fashions.\nConfigurations and sizes.\nThere are two types of planers for metal: double-housing and open-side. The double-housing variety has vertical supports on both sides of its long bed; the open-side variety has a vertical support on only one side, allowing the workpiece to extend beyond the bed. Metal planers can vary in size from a table size of 30\"×72\" to 20'×62', and in weight from around 20,000 lbs to over 1,000,000 lbs.\nHistory.\nEarly planing ideas are known to have been underway in France in the 1750s. In the late 1810s, a variety of pioneers in various British shops (including James Fox, George Rennie, Matthew Murray, Joseph Clement, and Richard Roberts) developed the planer into what we today would call a machine tool. The exact details have been contentious and will probably never be known, because the development work being done in various shops was undocumented for various reasons (partially because of proprietary secrecy, and also simply because no one was taking down records for posterity). Roe (1916) provides a short chapter that tells the story as thoroughly as he was able to discover it.", "Engineering,_Manufacturing": 0.9997913241, "qwen": "Yes"}
{"id": "2014402", "revid": "20394442", "url": "https://en.wikipedia.org/wiki?curid=2014402", "title": "Lead time", "text": "A lead time is the latency between the initiation and completion of a process. For example, the lead time between the placement of an order and delivery of new cars by a given manufacturer might be between 2 weeks and 6 months, depending on various particularities. One business dictionary defines \"manufacturing lead time\" as the total time required to manufacture an item, including order preparation time, queue time, setup time, run time, move time, inspection time, and put-away time. For make-to-order products, it is the time between release of an order and the production and shipment that fulfill that order. For make-to-stock products, it is the time taken from the release of an order to production and receipt into finished goods inventory.\nSupply chain management.\nA conventional definition of lead time in a supply chain management context is the time from the moment the customer places an order (the moment the supplier learns of the requirement) to the moment it is ready for delivery. In the absence of finished goods or intermediate (work in progress) inventory, it is the time it takes to actually manufacture the order without any inventory other than raw materials. The Chartered Institute of Procurement & Supply identifies \"total lead time\" as a combination of \"internal lead time\" (the time required for the buying organisation's internal processes to progress from identification of a need to the issue of a purchase order) and \"external lead time\" (the time required for the supplying organisation's processes, including any development required, manufacture, dispatch and delivery).\nManufacturing.\nIn the manufacturing environment, lead time has the same definition as that of Supply Chain Management, but it includes the time required to ship the parts from the supplier. Shipping time is included because the manufacturing company needs to know when the parts will be available for material requirements planning purposes. It is also possible to include within lead time the time it takes for a company to process and have the part ready for manufacturing once it has been received. The time it takes a company to unload a product from a truck, inspect it, and move it into storage (\"put-away time\") is not trivial. With tight manufacturing constraints or when a company is using Just In Time manufacturing, it is important for supply chain to know how long their own internal processes take.\nLead time consists of:\nExample\nCompany A needs a part that can be manufactured in two days once Company B has received an order. It takes three days for company A to receive the part once shipped, and one additional day before the part is ready to go into manufacturing.\nIn more detail\nLead Time terminology has been defined in greater detail. The Supply Chain from customer order received to the moment the order is delivered is divided into five lead times.\nExample \nA restaurant opens up and a customer walks in. A waiter guides him to a table, gives him the menu and asks what he would like to order. The customer selects a dish and the waiter writes it in his notepad. At that moment the customer has made an order which the restaurant has accepted – Order Lead Time and Order Handling Time have begun. Now the waiter marks the order in the cash register, rips the paper from the notepad, takes it into the kitchen and puts into the order queue. The order has been handled and is waiting in the factory (kitchen) for manufacturing. As there are no other customers, the waiter decides to stand outside the kitchen, by the door, waiting for the dish to be prepared and begins calculating Manufacturing Lead Time.\nMeanwhile, the chef finishes what he was doing, takes the order from the queue, starts his clock as a mark for the start of Production Lead Time and begins cooking. The chef chops the vegetables, fries the meat and boils the pasta. When the dish is ready, the chef rings a bell and stops his clock. At the same time, the waiter stops calculating Manufacturing Lead Time and rushes through the kitchen door to get the food while it is hot.\nWhen he picks it up, he begins timing the Delivery Lead Time that ends when the dish is served to the customer, who can now happily say that the Order Lead Time was shorter than he had expected.\nPossible ways of shortening the lead time: \nTo best meet the customer needs, a company should work towards the shortest possible lead time in manufacturing, production, and delivery. It can be helped by:\nOrder lead time.\nWhen talking about Order Lead Time (OLT) it is important to differentiate between the definitions that may exist around this concept. Although they look similar, there are differences between them that help the industry to model the order behavior of their customers. The four definitions are : \nOLT formulas.\nThe OLTRequested will be determined by the difference between the date the customer wants the material in his facilities (wish date) and the date when they provided its order to the supplier. \nThe OLTQuote will be determined by the difference between the date the customer agree to receive the material in their facilities (Quote date) and the date when the order is provided to the supplier.\nThe OLTActual will be determined by the difference between the day the provider deliver the material (Delivery date) and the date when they enter the order in the system. \nThe OLTConfirmed will be determined by the difference between the date the confirmed date by the provider to deliver the material in the customer facilities (Confirmed date) and the date when they provide the order to the supplier.\nAverage OLT based on volume.\nThe Average OLT based on Volume (OLTV) is the addition of all the multiplications between the volume of product we deliver (quantity) and the OLT divided by the total quantity delivered in the period of time we are studying for that specific facility.\nformula_1 \nBy doing this the company will be able to find a relation of volume weighted between the quantities of material required for an order and the time requested to accomplish it. The volume metric could be applied to the 4 types of OLT. \nThe figure obtained from this calculation will be the average time (e.g. in days) between order placing and the requested delivery date of a specific customer under consideration of the average quantities ordered during that particular time.\nPotential application areas for order lead time measurement.\nThe correct analysis of OLT will give the company:\nProject management.\nIn project management, lead time is the time it takes to complete a task or a set of interdependent tasks. The lead of the entire project would be the overall duration of the critical path for the project.\nAccording to the PMBOK (7th edition) by the Project Management Institute (PMI), lead time is the \"time between a customer request and the actual delivery.\" The lead time is a deliverable metric and a customary measure. The lead time shows the amount of elapsed time from a chunk of work or story entering the backlog, to the end of the iteration or release. A smaller lead time means that the process is more effective and the project team is more productive.\nLead time is also the saved time by starting an activity before its predecessor is completed.\nAccording to the PMBOK (7th edition) by PMI, lead is \"The amount of time whereby a successor activity can be advanced with respect to a predecessor activity\". An example would be scheduling the start of a 2-week activity dependent with the finish of the successor activity with a lead of 2 weeks so they will finish at the same time.\nJournalism.\nLead time in publishing describes the amount of time that a journalist has between receiving a writing assignment and submitting the completed piece. Depending on the publication, lead times can be anything from a couple of hours to many months/years.\nMedicine.\nLead time (when referring to a disease) is the length of time between detection of a disease through screening and the moment in time where it would have normally presented with symptoms and led to a diagnosis. An example of this is seen with breast cancer population screening, where women who are asymptomatic have a positive test result with mammography, whereas the underlying disease would have taken many more years to manifest.\nVideo games.\nLead time in video games can refer to the amount of time certain special, important actions in high-twitch action games, such as using health-recovering items, may need to take in order to be completed successfully. Lead time can be used to prevent players from abusing helpful abilities or items by making them a little more difficult to use safely, requiring some strategy, risk or caution.", "Engineering,_Manufacturing": 0.9998643398, "qwen": "Yes"}
{"id": "60186078", "revid": "22986354", "url": "https://en.wikipedia.org/wiki?curid=60186078", "title": "Solder alloys", "text": "Solder is a metallic material that is used to connect metal workpieces. The choice of specific solder alloys depends on their melting point, chemical reactivity, mechanical properties, toxicity, and other properties. Hence a wide range of solder alloys exist, and only major ones are listed below. Since early 2000s the use of lead in solder alloys is discouraged by several governmental guidelines in the European Union, Japan and other countries, such as Restriction of Hazardous Substances Directive and Waste Electrical and Electronic Equipment Directive. \nSolder alloys.\nNotes on the above table.\nIn the Sn-Pb alloys, tensile strength increases with increasing tin content. Indium-tin alloys with high indium content have very low tensile strength.\nFor soldering semiconductor materials, e.g. die attachment of silicon, germanium and gallium arsenide, it is important that the solder contains no impurities that could cause doping in the wrong direction. For soldering n-type semiconductors, solder may be doped with antimony; indium may be added for soldering p-type semiconductors. Pure tin can also be used.\nVarious fusible alloys can be used as solders with very low melting points; examples include Field's metal, Lipowitz's alloy, Wood's metal, and Rose's metal.\nProperties.\nThe thermal conductivity of common solders ranges from 30 to 400 W/(m·K), and the density from 9.25 to 15.00 g/cm3.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1860095", "revid": "44274926", "url": "https://en.wikipedia.org/wiki?curid=1860095", "title": "Turning", "text": "Turning is a machining process in which a cutting tool, typically a non-rotary tool bit, describes a helix toolpath by moving more or less linearly while the workpiece rotates.\nUsually the term \"turning\" is reserved for the generation of \"external\" surfaces by this cutting action, whereas this same essential cutting action when applied to \"internal\" surfaces (holes, of one kind or another) is called \"boring\". Thus the phrase \"turning and boring\" categorizes the larger family of processes known as lathing. The cutting of faces on the workpiece, whether with a turning or boring tool, is called \"facing\", and may be lumped into either category as a subset.\nTurning can be done manually, in a traditional form of lathe, which frequently requires continuous supervision by the operator, or by using an automated lathe which does not. Today the most common type of such automation is computer numerical control, better known as CNC. (CNC is also commonly used with many other types of machining besides turning.)\nWhen turning, the workpiece (a piece of relatively rigid material such as wood, metal, plastic, or stone) is rotated and a cutting tool is traversed along 1, 2, or 3 axes of motion to produce precise diameters and depths. Turning can be either on the outside of the cylinder or on the inside (also known as boring) to produce tubular components to various geometries. Although now quite rare, early lathes could even be used to produce complex geometric figures, even the platonic solids; although since the advent of CNC it has become unusual to use non-computerized toolpath control for this purpose.\nThe turning processes are typically carried out on a lathe, considered to be the oldest of machine tools, and can be of different types such as \"straight turning\", \"taper turning\", \"profiling\" or \"external grooving\". Those types of turning processes can produce various shapes of materials such as \"straight\", \"conical\", \"curved\", or \"grooved\" workpieces.\nIn general, turning uses simple \"single-point cutting\" tools. Each group of workpiece materials has an optimum set of tool angles that have been developed through the years.\nThe bits of waste metal from turning operations are known as chips (North America), or swarf (Britain). In some areas they may be known as \"turnings\".\nThe tool's axes of movement may be literally a straight line, or they may be along some set of curves or angles, but they are essentially linear (in the non mathematical sense).\nA component that is subject to turning operations can be termed as a “Turned Part” or “Machined Component”. Turning operations are carried out on a lathe machine which can be manually or CNC operated.\nTurning operations.\nTurning specific operations include:\nThe general process of turning involves rotating a part while a single-point cutting tool is moved parallel to the axis of rotation. Turning can be done on the external surface of the part as well as the internal surface (the process known as boring). The starting material is generally a workpiece generated by other processes such as casting, forging, extrusion, or drawing.\nFacing in the context of turning work involves moving the cutting tool at right angles to the axis of rotation of the rotating workpiece. This can be performed by the operation of the cross-slide, if one is fitted, as distinct from the longitudinal feed (turning). It is frequently the first operation performed in the production of the workpiece, and often the last—hence the phrase \"ending up\".\nThis process, also called parting off or cutoff, is used to create deep grooves which will remove a completed or part-complete component from its parent stock.\nGrooving is like parting, except that grooves are cut to a specific depth instead of severing a completed/part-complete component from the stock. Grooving can be performed on internal and external surfaces, as well as on the face of the part (face grooving or trepanning).\nNon-specific operations include:\nLathes.\nA lathe is a machine tool used principally for shaping pieces of metal, wood, or other materials by causing the workpiece to be held and rotated by the lathe while a tool bit is advanced into the work causing the cutting action. Lathes can be divided into three types for easy identification: engine lathe, turret lathe, and \"special purpose lathes\". Some smaller ones are bench mounted and semi-portable. The larger lathes are floor mounted and may require special transportation if they must be moved.\nField and maintenance shops generally use a lathe that can be adapted to many operations and that is not too large to be moved from one work site to another. The engine lathe is ideally suited for this purpose. A trained operator can accomplish more machining jobs with the engine lathe than with any other machine tool. Turret lathes and special purpose lathes are usually used in production or job shops for mass production or specialized parts, while basic engine lathes are usually used for any type of lathe work.\nTooling.\nThe various angles, shapes, and sizes of a \"single-point cutting\" tool have direct relation to the resulting surface of a workpiece in machining operations. Different types of angle such as \"rake angle\", \"side rake angle\", \"cutting-edge angle\", \"relief angle\", \"nose radius\" exist and may be different with respect to the workpiece. Also, there are many shapes of \"single-point cutting\" tools, such as \"V-shaped\" and \"Square.\" Usually, a special toolholder is used to hold the cutting tool firmly during operation.\nDynamics of turning.\nForces.\nThe relative forces in a turning operation are important in the design of machine tools. The machine tool and its components must be able to withstand these forces without causing significant deflections, vibrations, or chatter during the operation. There are three principal forces during a turning process:\nSpeeds and feeds.\nSpeeds and feeds for turning are chosen based on cutter material, workpiece material, setup rigidity, machine tool rigidity and spindle power, coolant choice, and other factors.", "Engineering,_Manufacturing": 0.9999490976, "qwen": "Yes"}
{"id": "1860640", "revid": "1540803", "url": "https://en.wikipedia.org/wiki?curid=1860640", "title": "Wire drawing", "text": "Wire drawing is a metalworking process used to reduce the cross-section of a wire by pulling the wire through a single, or series of, drawing die(s). There are many applications for wire drawing, including electrical wiring, cables, tension-loaded structural components, springs, paper clips, spokes for wheels, and stringed musical instruments. Although similar in process, drawing is different from extrusion, because in drawing the wire is pulled, rather than pushed, through the die. Drawing is usually performed at room temperature, thus classified as a cold working process, but it may be performed at elevated temperatures for large wires to reduce forces.\nOf the elemental metals, copper, silver, gold, and platinum are the most ductile and immune from many of the problems associated with cold working.\nProcess.\nThe wire drawing process is quite simple in concept. The wire is prepared by shrinking the beginning of it, by hammering, filing, rolling or swaging, so that it will fit through the die; the wire is then pulled through the die. As the wire is pulled through the die, its volume remains the same, so as the diameter decreases, the length increases. Usually the wire will require more than one draw, through successively smaller dies, to reach the desired size. The American wire gauge scale is based on this. This can be done on a small scale with a draw plate, or on a large commercial scale using automated machinery. The process of wire drawing changes material properties due to cold working.\nThe area reduction in small wires is generally 15–25% and in larger wires is 20–45%. The exact die sequence for a particular job is a function of area reduction, input wire size and output wire size. As the area reduction changes, so does the die sequence.\nVery fine wires are usually drawn in bundles. In a bundle, the wires are separated by a metal with similar properties, but with lower chemical resistance so that it can be removed after drawing. If the reduction in area is greater than 50%, the process may require an intermediate step of annealing before it can be redrawn.\nCommercial wire drawing usually starts with a coil of hot rolled diameter wire. The surface is first treated to remove scales. It is then fed into a wire drawing machine which may have one or more blocks in series.\nSingle block wire drawing machines include means for holding the dies accurately in position and for drawing the wire steadily through the holes. The usual design consists of a cast-iron bench or table having a bracket standing up to hold the die, and a vertical drum which rotates and by coiling the wire around its surface pulls it through the die, the coil of wire being stored upon another drum or \"swift\" which lies behind the die and reels off the wire as fast as required. The wire drum or \"block\" is provided with means for rapidly coupling or uncoupling it to its vertical shaft, so that the motion of the wire may be stopped or started instantly. The block is also tapered, so that the coil of wire may be easily slipped off upwards when finished. Before the wire can be attached to the block, a sufficient length of it must be pulled through the die; this is effected by a pair of gripping pincers on the end of a chain which is wound around a revolving drum, so drawing the wire until enough can be coiled two or three times on the block, where the end is secured by a small screw clamp or vice. When the wire is on the block, it is set in motion and the wire is drawn steadily through the die; it is very important that the block rotates evenly and that it runs true and pulls the wire at a constant velocity, otherwise \"snatching\" occurs which will weaken or even break the wire. The speeds at which wire is drawn vary greatly, according to the material and the amount of reduction.\nMachines with continuous blocks differ from single block machines by having a series of dies through which the wire is drawn in a continuous fashion. Due to the elongation and slips, the speed of the wire changes after each successive redraw. This increased speed is accommodated by having a different rotation speed for each block. One of these machines may contain 3 to 12 dies. The operation of threading the wire through all the dies and around the blocks is termed \"stringing-up\". The arrangements for lubrication include a pump which floods the dies, and in many cases also the bottom portions of the blocks run in lubricant.\nOften intermediate anneals are required to counter the effects of cold working, and to allow further drawing. A final anneal may also be used on the finished product to maximize ductility and electrical conductivity.\nAn example of product produced in a continuous wire drawing machine is telephone wire. It is drawn 20 to 30 times from hot rolled rod stock.\nWhile round cross-sections dominate most drawing processes, non-circular cross-sections are drawn. They are usually drawn when the cross-section is small and quantities are too low to justify rolling. In these processes, a block or Turk's-head machine are used.\nLubrication.\nLubrication in the drawing process is essential for maintaining good surface finish and long die life. The following are different methods of lubrication:\nVarious lubricants, such as oil, are employed. Another lubrication method is to immerse the wire in a copper(II) sulfate solution, such that a film of copper is deposited which forms a kind of lubricant. In some classes of wire the copper is left after the final drawing to serve as a preventive of rust or to allow easy soldering.The best example of copper coated wire is in MIG wire used in welding.\nMechanical properties.\nThe strength-enhancing effect of wire drawing can be substantial. The highest strengths available on any steel have been recorded on small-diameter cold-drawn austenitic stainless wire.\nDrawing dies.\nDrawing dies are typically made of tool steel, tungsten carbide, or diamond, with tungsten carbide and manufactured diamond being the most common. For drawing very fine wire a single crystal diamond die is used. For hot drawing, cast-steel dies are used. For steel wire drawing, a tungsten carbide die is used. The dies are placed in a steel casing, which backs the die and allow for easy die changes. Die angles usually range from 6–15°, and each die has at least 2 different angles: the entering angle and approach angle.", "Engineering,_Manufacturing": 0.9995132685, "qwen": "Yes"}
{"id": "1864594", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=1864594", "title": "Transaction printing", "text": "Transaction Printing describes a mode of submitting a job to a printing device.\nA digital printing system is attached to a computer database and many similar pages, called forms, are printed; each, for example, with a different person's data filling the form such as a monthly telephone or cable bill.\nSimply stated, transaction printing is the printing of multiple transactions for each customer along with the fixed line details like name and address. \nThis is more used in BFSI sectors, for example, bank statements.\nTransaction printing jobs are similar to, but often more complex than variable data printing jobs such as mail merge.\nTransaction printing frequently requires customized formatting to present transaction data in a printable and customer-readable format.\nCurrently, printing applications are designed to print transactional details along with the external information (not available in the transaction database), often involving promotional material.\nTransaction print jobs are different from 'publishing' print jobs in that the print controller does not know when the job will end when it starts. A transactional print job may involve a hundred, a thousand, or a few million impressions. Many digital printing system's controllers are designed to ingest the entire job, arrange its resources according to the size of the job and then begin printing the job last page first so that what is produced is a 'book' with the user seeing the first page first. This 'publishing' model obviously does not work for 'transaction' printing and a controller using a different internal model for jobs must be used.", "Engineering,_Manufacturing": 0.7901260257, "qwen": "Yes"}
{"id": "3002380", "revid": "36729223", "url": "https://en.wikipedia.org/wiki?curid=3002380", "title": "Crankpin", "text": "A crankpin or crank pin, also known as a rod bearing journal, is a mechanical device in an engine which connects the crankshaft to the connecting rod for each cylinder. It has a cylindrical surface, to allow the crankpin to rotate relative to the \"big end\" of the connecting rod.\nThe most common configuration is for a crankpin to serve one cylinder. However, many V engines have each crankpin shared by each pair of cylinders.\nDesign.\nThe crankpin connects to the larger end of the connecting rod for each cylinder. This end of the connecting rod is called the \"big end\", as opposed to the \"small end\" or \"little end\" (which connects to the wrist/gudgeon pin in the piston).\nThe bearing which allows the crankpin to rotate around its shaft is called the \"rod bearing\". In automotive engines, the most common type of rod bearing is the plain bearing, however bushings or roller bearings are also used in some engines.\nConfigurations.\nIn a single-cylinder engine, straight engine or flat engine, each crankpin normally serves just one cylinder. This results for a relatively simple design which is the cheapest to produce. Some V-twin engines use a single cylinder per crankpin.\nMost V engines have each pair of cylinders sharing a crankpin. This usually requires an offset between the cylinders in each bank, resulting in a simple connecting rod design. If a cylinder offset is not used, then the connecting rods must be articulated or forked at the big end. Forked connecting rods are mainly used in V-twin motorcycle engines, but in the past were found on a number of automobile and aero engines, such as the Rolls-Royce Merlin aero engine of the WWII era. Articulated connecting rods consist of a \"master\" rod attached to the crank pin, with a \"slave\" rod connected to the big end of the master rod. This design was used in older or exotic V engines.\nRadial engines use a more complicated version of articulated connecting rods, where a single \"master\" connecting rod attached to the single crankpin (one for each row in multi-row designs), and smaller bearings for each of the corresponding cylinders machined into the big end of the master rod.\nCylindrical crank pins were fitted onto the driving wheels of steam locomotives. They were connected to the driving rods that transmitted power from the cylinder to the wheel. The crank pin was usually made of high-quality steel because it had to withstand high forces.\nThe crank pin of a locomotive corresponds to the offset of a crankshaft in other crank drives. The distance from the centre of the crank pin to the centre of the wheel is also called offset and is exactly half the stroke of the pistons.", "Engineering,_Manufacturing": 0.9999371767, "qwen": "Yes"}
{"id": "3003010", "revid": "1147286221", "url": "https://en.wikipedia.org/wiki?curid=3003010", "title": "Electroforming", "text": "Electroforming is a metal forming process in which parts are fabricated through electrodeposition on a model, known in the industry as a mandrel. Conductive (metallic) mandrels are treated to create a mechanical parting layer, or are chemically passivated to limit electroform adhesion to the mandrel and thereby allow its subsequent separation. Non-conductive (glass, silicon, plastic) mandrels require the deposition of a conductive layer prior to electrodeposition. Such layers can be deposited chemically, or using vacuum deposition techniques (e.g., gold sputtering). The outer surface of the mandrel forms the inner surface of the form. \nThe process involves passing direct current through an electrolyte containing salts of the metal being electroformed. The anode is the solid metal being electroformed, and the cathode is the mandrel, onto which the electroform gets plated (deposited). The process continues until the required electroform thickness is achieved. The mandrel is then either separated intact, melted away, or chemically dissolved.\nThe surface of the finished part that was in intimate contact with the mandrel is replicated in fine detail with respect to the original, and is not subject to the shrinkage that would normally be experienced in a foundry cast metal object, or the tool marks of a milled part. The solution side of the part is less well defined, and that loss of definition increases with thickness of the deposit. In extreme cases, where a thickness of several millimetres is required, there is preferential build-up of material on sharp outside edges and corners. This tendency can be reduced by shielding, or a process known as periodic reverse, where the electroforming current is reversed for short periods and the excess is preferentially dissolved electrochemically. The finished form can either be the finished part, or can be used in a subsequent process to produce a positive of the original mandrel shape, such as with vinyl records or CD and DVD stamper manufacture.\nIn recent years, due to its ability to replicate a mandrel surface with practically no loss of fidelity, electroforming has taken on new importance in the fabrication of micro and nano-scale metallic devices and in producing precision injection molds with micro- and nano-scale features for production of non-metallic micro-molded objects.\nProcess.\nIn the basic electroforming process, an electrolytic bath is used to deposit nickel or other electroformable metal onto a conductive surface of a model (mandrel). Once the deposited material has been built up to the desired thickness, the electroform is parted from the substrate. This process allows precise replication of the mandrel surface texture and geometry at low unit cost with high repeatability and excellent process control.\nIf the mandrel is made of a non-conductive material it can be coated with a thin conductive layer.\nAdvantages and disadvantages.\nThe main advantage of electroforming is that it accurately replicates the external shape of the mandrel. Generally, machining a cavity accurately is more challenging than machining a convex shape, however the opposite holds true for electroforming because the mandrel's exterior can be accurately machined and then used to electroform a precision cavity.\nCompared to other basic metal forming processes (casting, forging, stamping, deep drawing, machining and fabricating) electroforming is very effective when requirements call for extreme tolerances, complexity or light weight. The precision and resolution inherent in the photo-lithographically produced conductive patterned substrate, allows finer geometries to be produced to tighter tolerances while maintaining superior edge definition with a near optical finish. Electroformed metal can be extremely pure, with superior properties over wrought metal due to its refined crystal structure. Multiple layers of electroformed metals can be bonded together, or to different substrate materials to produce complex structures with \"grown-on\" flanges and bosses.\nTolerances of 1.5 to 3 nanometres have been reported.\nA wide variety of shapes and sizes can be made by electroforming, the principal limitation being the need to part the product from the mandrel. Since the fabrication of a product requires only a single model or mandrel, low production quantities can be made economically.", "Engineering,_Manufacturing": 1.0000072718, "qwen": "Yes"}
{"id": "48028112", "revid": "18285885", "url": "https://en.wikipedia.org/wiki?curid=48028112", "title": "Demand signal", "text": "A demand signal is a message issued within business operations or within a supply chain to notify a supplier that goods are required, and is, therefore, a key item of information for demand planners within a business.\nContexts.\nIn a Just-in-time manufacturing or operations context, a demand signal identifies a need for new materials and triggers a delivery from an internal store or an external supplier. The Kanban system uses cards ('Kanban cards') to mark the stock level at which a replenishment signal needs to be issued. Kanban cards are a key component of a kanban system as they signal the need to move materials within a production facility or to move materials from an outside supplier into the production facility. The kanban card is, in effect, a message which signals depletion of product, parts, or inventory. When received, the kanban triggers replenishment of that product, part, or inventory. Consumption, therefore, drives demand for more production, and the kanban card signals demand more product — so kanban cards help create a demand-driven system. \nIn the context of an Enterprise Resource Planning (ERP) system, demand signals function as granular data indicating discrete requests for the supply or use of a resource. Demand Signal Management (DSiM) provides a means of harmonizing demand data so that it can be used in demand planning. Demand signals must bring together data on actual sales and date on unfulfilled demand in order to be effective.", "Engineering,_Manufacturing": 0.9969098568, "qwen": "Yes"}
{"id": "10375926", "revid": "18308978", "url": "https://en.wikipedia.org/wiki?curid=10375926", "title": "Metal bellows", "text": "Metal bellows are elastic vessels that can be compressed when pressure is applied to the outside of the vessel, or extended under vacuum. When the pressure or vacuum is released, the bellows will return to its original shape, provided the material has not been stressed past its yield strength. They are used both for their ability to deform under pressure and to provide a hermetic seal that allows movement.\nPrecision bellows technology of the 20th and 21st century is centered on metal bellows with less demanding applications using ones made of rubber and plastic. These products bear little resemblance to the original leather bellows used traditionally in fireplaces and forges.\nTypes.\nThere are three main types of metal bellows: formed, welded and electroformed.\nFormed bellows are produced by reworking tubes, normally produced by deep drawing, with a variety of processes, including cold forming (rolling), and hydroforming. They are also called convoluted bellows or sylphons.\nWelded bellows (also called edge-welded, or diaphragm bellows) are manufactured by welding a number of individually formed diaphragms to each other. The comparison between the two bellows types generally centers on cost and performance. Hydroformed bellows generally have a high tooling cost, but, when mass-produced, may have a lower piece price. However, hydroformed bellows have lower performance characteristics due to relatively thick walls and high stiffness. Welded metal bellows are produced with a lower initial tooling cost and maintain higher performance characteristics. The drawback of welded bellows is the reduced metal strength at weld joints, caused by the high temperature of welding.\nElectroformed bellows are produced by plating (electroforming) a metal layer onto a model (mandrel), and subsequently removing the mandrel. They can be produced with modest tooling costs and with thin walls (25 micrometres or less), providing such bellows with high sensitivity and precision in many exacting applications, and may also be produced in shapes that would be exceptionally difficult to produce by other means with little additional difficulty.\nAnother area of comparison is in metals of construction. Hydroformed and rolled bellows are limited to metals with high plastic elongation characteristics, whereas welded bellows may be fabricated from a wider variety of standard and exotic alloys, such as stainless steel and titanium, as well as other high-strength, corrosion-resistant materials. Electroformed bellows can be produced of nickel, its high-strength alloys, and copper.\nApplications.\nMetal bellows are used in a large number of industrial applications. Below you will find a few;\nManufacture.\nWelded bellows can be fabricated from a variety of exotic metals and alloys, whereas formed bellows are limited to alloys with good elongation – brass being a prime example. Welded bellows are not fabricated from brass because of its fundamentally poor weldability. Other advantages to welded bellows include compactness (higher performance in a smaller package), ability to be compressed to solid height with no damage, resistance to nicks and dents, and dramatically greater flexibility.\nThe welding of metal bellows is a microscopic welding process, typically performed under laboratory conditions at high magnification.\nHydroformed bellows are produced by forcing a metal tube to expand under hydraulic pressure inside a bellows-shaped mold, and assume the convoluted shape of the mold.\nElectroformed bellows are produced by plating metal onto a bellows-shaped model (mandrel), and the subsequent mandrel removal by chemical or physical means. Due to the low tooling cost and short manufacturing cycle, electroforming of bellows is not only an inexpensive manufacturing method, but also a perfect prototyping tool.\nDeflections.\nThere are a variety of expansion joints and not each one can accept the same types of deflection. The various types of deflections are axial, lateral, angular, torsional, cyclic, or any combination that can occur at the same time.", "Engineering,_Manufacturing": 0.9999912977, "qwen": "Yes"}
{"id": "44224167", "revid": "41840956", "url": "https://en.wikipedia.org/wiki?curid=44224167", "title": "Process validation", "text": "Process validation is the analysis of data gathered throughout the design and manufacturing of a product in order to confirm that the process can reliably output products of a determined standard. Regulatory authorities like EMA and FDA have published guidelines relating to process validation. The purpose of process validation is to ensure varied inputs lead to consistent and high quality outputs. Process validation is an ongoing process that must be frequently adapted as manufacturing feedback is gathered. End-to-end validation of production processes is essential in determining product quality because quality cannot always be determined by finished-product inspection. Process validation can be broken down into 3 steps: process design (Stage 1a, Stage 1b), process qualification (Stage 2a, Stage 2b), and continued process verification (Stage 3a, Stage 3b).\nStage 1: Process Design.\nIn this stage, data from the development phase are gathered and analyzed to define the commercial manufacturing process. By understanding the commercial process, a framework for quality specifications can be established and used as the foundation of a control strategy. Process design is the first of three stages of process validation. Data from the development phase is gathered and analyzed to understand end-to-end system processes. These data are used to establish benchmarks for quality and production control.\nDesign of experiment (DOE).\nDesign of experiments is used to discover possible relationships and sources of variation as quickly as possible. A cost-benefit analysis should be conducted to determine if such an operation is necessary.\nQuality by design (QBD).\nQuality by design is an approach to pharmaceutical manufacturing that stresses quality should be built into products rather than tested in products; that product quality should be considered at the earliest possible stage rather than at the end of the manufacturing process. Input variables are isolated in order to identify the root cause of potential quality issues and the manufacturing process is adapted accordingly.\nProcess analytical technology (PAT).\nProcess analytical technology is used to measure critical process parameters (CPP) and critical quality attributes (CQA). PAT facilitates measurement of quantitative production variables in real time and allows access to relevant manufacturing feedback. PAT can also be used in the design process to generate a process qualification.\nCritical process parameters (CPP).\nCritical process parameters are operating parameters that are considered essential to maintaining product output within specified quality target guidelines.\nCritical quality attributes (CQA).\nCritical quality attributes (CQA) are chemical, physical, biological, and microbiological attributes that can be defined, measured, and continually monitored to ensure final product outputs remain within acceptable quality limits. CQA are an essential aspect of a manufacturing control strategy and should be identified in stage 1 of process validation: process design. During this stage, acceptable limits, baselines, and data collection and measurement protocols should be established. Data from the design process and data collected during production should be kept by the manufacturer and used to evaluate product quality and process control. Historical data can also help manufacturers better understand operational process and input variables as well as better identify true deviations from quality standards compared to false positives. Should a serious product quality issue arise, historical data would be essential in identifying the sources of errors and implementing corrective measures.\nStage 2: Process Performance Qualification.\nIn this stage, the process design is assessed to conclude if the process is able to meet determined manufacturing criteria. In this stage all production processes and manufacturing equipment is proofed to confirm quality and output capabilities. Critical quality attributes are evaluated, and critical process parameters taken into account, to confirm product quality. Once the process qualification stage has been successfully accomplished, production can begin. Process Performance Qualification is the second phase of process validation.\nStage 3: Continued Process Verification.\nContinued process verification is the ongoing monitoring of all aspects of the production cycle. It aims to ensure that all levels of production are controlled and regulated. Deviations from prescribed output methods and final product irregularities are flagged by a process analytics database system. The FDA requires production data be recorded (FDA requirements (§ 211.180(e)). Continued process verification is stage 3 of process validation.\nThe European Medicines Agency defines a similar process known as \"ongoing process verification\". This alternative method of process validation is recommended by the EMA for validating processes on a continuous basis. Continuous process verification analyses critical process parameters and critical quality attributes in real time to confirm production remains within acceptable levels and meets standards set by ICH Q8, Pharmaceutical Quality Systems, and Good manufacturing practice.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "4600562", "revid": "6727347", "url": "https://en.wikipedia.org/wiki?curid=4600562", "title": "Surface finish", "text": "Surface finish, also known as surface texture or surface topography, is the nature of a surface as defined by the three characteristics of lay, surface roughness, and waviness. It comprises the small, local deviations of a surface from the perfectly flat ideal (a true plane).\nSurface texture is one of the important factors that control friction and transfer layer formation during sliding. Considerable efforts have been made to study the influence of surface texture on friction and wear during sliding conditions. Surface textures can be isotropic or anisotropic. Sometimes, stick-slip friction phenomena can be observed during sliding, depending on surface texture.\nEach manufacturing process (such as the many kinds of machining) produces a surface texture. The process is usually optimized to ensure that the resulting texture is usable. If necessary, an additional process will be added to modify the initial texture. The latter process may be grinding (abrasive cutting), polishing, lapping, abrasive blasting, honing, electrical discharge machining (EDM), milling, lithography, industrial etching/chemical milling, laser texturing, or other processes.\nLay.\nLay is the direction of the predominant surface pattern, ordinarily determined by the production method used. The term is also used to denote the winding direction of fibers and strands of a rope.\nSurface roughness.\nSurface roughness, commonly shortened to \"roughness,\" is a measure of the total spaced surface irregularities. In engineering, this is what is usually meant by \"surface finish.\" A Lower number constitutes finer irregularities, i.e., a smoother surface.\nWaviness.\nWaviness is the measure of surface irregularities with a spacing greater than that of surface roughness. These irregularities usually occur due to warping, vibrations, or deflection during machining.\nMeasurement.\nSurface finish may be measured in two ways: \"contact\" and \"non-contact\" methods. Contact methods involve dragging a measurement stylus across the surface; these instruments are called profilometers. Non-contact methods include: interferometry, confocal microscopy, focus variation, structured light, electrical capacitance, electron microscopy, atomic force microscopy and photogrammetry.\nSpecification.\nIn the United States, surface finish is usually specified using the ASME Y14.36M standard. The other common standard is International Organization for Standardization (ISO) 1302:2002, although the same has been withdrawn in favour of ISO 21920-1:2021.\nMany factors contribute to the surface finish in manufacturing. In forming processes, such as molding or metal forming, surface finish of the die determines the surface finish of the workpiece. In machining, the interaction of the cutting edges and the microstructure of the material being cut both contribute to the final surface finish.\nIn general, the cost of manufacturing a surface increases as the surface finish improves. Any given manufacturing process is usually optimized enough to ensure that the resulting texture is usable for the part's intended application. If necessary, an additional process will be added to modify the initial texture. The expense of this additional process must be justified by adding value in some way—principally better function or longer lifespan. Parts that have sliding contact with others may work better or last longer if the roughness is lower. Aesthetic improvement may add value if it improves the saleability of the product.\nA practical example is as follows. An aircraft maker contracts with a vendor to make parts. A certain grade of steel is specified for the part because it is strong enough and hard enough for the part's function. The steel is machinable although not free-machining. The vendor decides to mill the parts. The milling can achieve the specified roughness (for example, ≤ 3.2 μm) as long as the machinist uses premium-quality inserts in the end mill and replaces the inserts after every 20 parts (as opposed to cutting hundreds before changing the inserts). There is no need to add a second operation (such as grinding or polishing) after the milling as long as the milling is done well enough (correct inserts, frequent-enough insert changes, and clean coolant). The inserts and coolant cost money, but the costs that grinding or polishing would incur (more time and additional materials) would cost even more than that. Obviating the second operation results in a lower unit cost and thus a lower price. The competition between vendors elevates such details from minor to crucial importance. It was certainly possible to make the parts in a slightly less efficient way (two operations) for a slightly higher price; but only one vendor can get the contract, so the slight difference in efficiency is magnified by competition into the great difference between the prospering and shuttering of firms.\nJust as different manufacturing processes produce parts at various tolerances, they are also capable of different roughnesses. Generally, these two characteristics are linked: manufacturing processes that are dimensionally precise create surfaces with low roughness. In other words, if a process can manufacture parts to a narrow dimensional tolerance, the parts will not be very rough.\nDue to the abstractness of surface finish parameters, engineers usually use a tool that has a variety of surface roughnesses created using different manufacturing methods.", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "49202119", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=49202119", "title": "Diffusion bonding", "text": "Diffusion bonding or diffusion welding is a solid-state welding technique used in metalworking, capable of joining similar and dissimilar metals. It operates on the principle of solid-state diffusion, wherein the atoms of two solid, metallic surfaces intersperse themselves over time. This is typically accomplished at an elevated temperature, approximately 50-75% of the absolute melting temperature of the materials. Diffusion bonding is usually implemented by applying high pressure, in conjunction with necessarily high temperature, to the materials to be welded; the technique is most commonly used to weld \"sandwiches\" of alternating layers of thin metal foil, and metal wires or filaments. Currently, the diffusion bonding method is widely used in the joining of high-strength and refractory metals within the aerospace and nuclear industries.\nHistory.\nThe act of diffusion welding is centuries old. This can be found in the form of \"gold-filled,\" a technique used to bond gold and copper for use in jewelry and other applications. In order to create filled gold, smiths would begin by hammering out an amount of solid gold into a thin sheet of gold foil. This film was then placed on top of a copper substrate and weighted down. Finally, using a process known as \"hot-pressure welding\" or HPW, the weight/copper/gold-film assembly was placed inside an oven and heated until the gold film was sufficiently bonded to the copper substrate.\nModern methods were described by the Soviet scientist N.F. Kazakov in 1953.\nCharacteristics.\nDiffusion bonding involves no liquid fusion, and often no filler metal. No weight is added to the total, and the join tends to exhibit both the strength and temperature resistance of the base metal(s). The materials endure no, or very little, plastic deformation. Very little residual stress is introduced, and there is no contamination from the bonding process. It may theoretically be performed on a join surface of any size with no increase in processing time, however, practically speaking, the surface tends to be limited by the pressure required and physical limitations. Diffusion bonding may be performed with similar and dissimilar metals, reactive and refractory metals, or pieces of varying thicknesses.\nDue to its relatively high cost, diffusion bonding is most often used for jobs either difficult or impossible to weld by other means. Examples include welding materials normally impossible to join via liquid fusion, such as zirconium and beryllium; materials with very high melting points such as tungsten; alternating layers of different metals which must retain strength at high temperatures; and very thin, honeycombed metal foil structures. Titanium alloys will often be diffusion bonded despite as the thin oxide layer can be dissolved and diffused away from the bonding surfaces at temperatures over 850 °C.\nTemperature Dependence.\nSteady state diffusion is determined by the amount of diffusion flux that passes through the cross-sectional area of the mating surfaces. Fick's first law of diffusion states:\nwhere \"J\" is the diffusion flux, \"D\" is a diffusion coefficient, and \"dC\"/\"dx\" is the concentration gradient through the materials in question. The negative sign is a product of the gradient. Another form of Fick's law states:\nwhere \"M\" is defined as either the mass or amount of atoms being diffused, \"A\" is the cross-sectional area, and \"t\" is the time required. Equating the two equations and rearranging, we achieve the following result:\nAs mass and area are constant for a given joint, time required is largely dependent on the concentration gradient, which changes by only incremental amounts through the joint, and the diffusion coefficient. The diffusion coefficient is determined by the equation:\nwhere \"Q\"d is the activation energy for diffusion, \"R\" is the universal gas constant, \"T\" is the thermodynamic temperature experienced during the process, and \"D\"0 is a temperature-independent preexponential factor that depends on the materials being joined. For a given joint, the only term in this equation within control is temperature.\nProcesses.\nWhen joining two materials of similar crystalline structure, diffusion bonding is performed by clamping the two pieces to be welded with their surfaces abutting each other. Prior to welding, these surfaces must be machined to as smooth a finish as economically viable, and kept as free from chemical contaminants or other detritus as possible. Any intervening material between the two metallic surfaces may prevent adequate diffusion of material. Specific tooling is made for each welding application to mate the welder to the workpieces. Once clamped, pressure and heat are applied to the components, usually for many hours. The surfaces are heated either in a furnace, or via electrical resistance. Pressure can be applied using a hydraulic press at temperature; this method allows for exact measurements of load on the parts. In cases where the parts must have no temperature gradient, differential thermal expansion can be used to apply load. By fixturing parts using a low-expansion metal (i.e. molybdenum) the parts will supply their own load by expanding more than the fixture metal at temperature. Alternative methods for applying pressure include the use of dead weights, differential gas pressure between the two surfaces, and high-pressure autoclaves. Diffusion bonding must be done in a vacuum or inert gas environment when using metals that have strong oxide layers (i.e. copper). Surface treatment including polishing, etching, and cleaning as well as diffusion pressure and temperature are important factors regarding the process of diffusion bounding.\nAt the microscopic level, diffusion bonding occurs in three simplified stages: \nApplicability.\nDiffusion bonding is primarily used to create intricate forms for the electronics, aerospace, nuclear, and microfluidics industries. Since this form of bonding takes a considerable amount of time compared to other joining techniques such as explosion welding, parts are made in small quantities, and often fabrication is mostly automated. However, due to different requirements, the required time could be reduced. In an attempt to reduce fastener count, labor costs, and part count, diffusion bonding, in conjunction with superplastic forming, is also used when creating complex sheet metal forms. Multiple sheets are stacked atop one another and bonded in specific sections. The stack is then placed into a mold and gas pressure expands the sheets to fill the mold. This is often done using titanium or aluminum alloys for parts needed in the aerospace industry.\nTypical materials that are welded include titanium, beryllium, and zirconium. In many military aircraft diffusion bonding will help to allow for the conservation of expensive strategic materials and the reduction of manufacturing costs. Some aircraft have over 100 diffusion-bonded parts, including fuselages, outboard and inboard actuator fittings, landing gear trunnions, and nacelle frames.", "Engineering,_Manufacturing": 0.9999479055, "qwen": "Yes"}
{"id": "49213295", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=49213295", "title": "Self-assembly based manufacturing", "text": "Self-assembly based manufacturing refers to a controlled process of using self-assembly and programmable matter to manufacture a product on an industrial scale. In traditional manufacturing and fabrication, there are physical and precision limitations on a workpiece; namely, lower minimal dimension of a workpiece has been a major challenge in modern manufacturing. Engineering self-assembly methods have a significant potentials in overcoming the dimensional limitation of a workpiece. In general, there are three key ingredients in most of self assembly applications: geometry (order), interaction, energy. To improve the efficiency or take shape in self-assembly based manufacturing, it must utilize one or more than one of these three ingredients. This is an emerging market with few examples to date. However, this field shows a strong potential to revolutionize many industrial markets from nanoelectronics to bio-engineering.\nSuccessful processes.\nMany processes have been successfully developed at laboratory scale and show promise for future expansion into large-scale industrial manufacturing. \nOne example is the automated reel to reel fluidic self-assembly machine demonstrated by University of Minnesota researchers. The machine was designed to produce lighting panels using Light-emitting diodes. Assembly was performed at twice the hourly rate of commercially available pick and place machines for SMT placement equipment, 15,000 chips per hour compared to 8,000 chips per hour. At the same time, the self-assembly exceeded the accuracy rate of the pick and place machine as well.\nPotential future applications.\nFabrication of materials used in most extreme environments, such as space, high altitude, free-fall scenarios, or deep sea. environments have advantageous conditions for allowing increase in self assembly interaction with less or minimum energy consumption. Applications in these environments often require high precision and have more difficulties; however, it has less constraints in existing construction.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "49219456", "revid": "39192732", "url": "https://en.wikipedia.org/wiki?curid=49219456", "title": "Solder ball", "text": "In integrated circuit packaging, a solder ball, also a solder bump (often referred to simply as \"ball\" or \"bumps\") is a ball of solder that provides the contact between the chip package and the printed circuit board, as well as between stacked packages in multichip modules; in the latter case, they may be referred to as microbumps (μbumps, ubumps), since they are usually significantly smaller than the former. The solder balls can be placed manually or by automated equipment, and are held in place with a tacky flux.\nA coined solder ball is a solder ball subject to coining, i.e., flattening to a shape resembling that of a coin, to increase contact reliability.\nThe ball grid array, chip-scale package, and flip chip packages generally use solder balls.\nUnderfill.\nAfter the solder balls are used to attach an integrated circuit chip to a PCB, often the remaining air gap between them is underfilled with epoxy.\nIn some cases, there may be multiple layers of solder balls—for example, one layer of solder balls attaching a flip chip to an interposer to form a BGA package, and a second layer of solder balls attaching that interposer to the PCB. Often both layers are underfilled.", "Engineering,_Manufacturing": 0.9998304248, "qwen": "Yes"}
{"id": "49223902", "revid": "10289486", "url": "https://en.wikipedia.org/wiki?curid=49223902", "title": "Laser beam machining", "text": "Laser beam machining (LBM) is a form of machining that uses heat directed from a laser beam. This process uses thermal energy to remove material from metallic or nonmetallic surfaces. The high frequency of monochromatic light will fall on the surface, thus heating, melting and vaporizing the material due to the impinge of photons (see Coulomb explosion).\nLaser beam machining is best suited for brittle materials with low conductivity, but can be used on most materials.\nLaser beam machining can be done on glass without melting the surface. With photosensitive glass, the laser alters the chemical structure of the glass allowing it to be selectively etched. The glass is also referred to as photomachinable glass. The advantage of photomachinable glass is that it can produce precisely vertical walls and the native glass is suitable for many biological applications such as substrates for genetic analysis.\nTypes of lasers.\nThere are many different types of lasers including gas, solid states lasers, and excimer.\nSome of the most commonly used gases consist of; He-Ne, Ar, and Carbon dioxide laser.\nSolid-state lasers are designed by doping a rare element into various host materials. Unlike in gas lasers, solid state lasers are pumped optically by flash lamps or arc lamps. Ruby is one of the frequently used host materials in this type of laser. A ruby laser is a type of the solid state laser whose laser medium is a synthetic ruby crystal. The synthetic ruby rod is optically pumped using a xenon flashtube before it is used as an active laser medium.\nYAG is an abbreviation for yttrium aluminum garnet which are crystals that are used for solid-state lasers while refers to neodymium-doped yttrium aluminum garnet crystals that are used in the solid-state lasers as the laser mediate.\nYAG lasers emit a wavelength of light waves with high energy. is neodymium–doped gain media made of either silicate or phosphate materials that are used in fiber laser.\nCutting depth.\nThe cutting depth of a laser is directly proportional to the quotient obtained by dividing the power of the laser beam by the product of the cutting velocity and the diameter of the laser beam spot.\nwhere \"t\" is the depth of cut, \"P\" is the laser beam power, \"v\" is the cutting velocity, and \"d\" is the laser beam spot diameter.\nThe depth of the cut is also influenced by the workpiece material. The material's reflectivity, density, specific heat, and melting point temperature all contribute to the lasers ability to cut the workpiece.\nThe following table shows the ability of different lasers to cut different materials:\nApplications.\nLasers can be used for welding, cladding, marking, surface treatment, drilling, and cutting among other manufacturing processes. It is used in the automobile, shipbuilding, aerospace, steel, electronics, and medical industries for precision machining of complex parts.\nLaser welding is advantageous in that it can weld at speeds of up to 100 mm/s as well as the ability to weld dissimilar metals. Laser cladding is used to coat cheap or weak parts with a harder material in order to improve the surface quality. Drilling and cutting with lasers is advantageous in that there is little to no wear on the cutting tool as there is no contact to cause damage.\nMilling with a laser is a three dimensional process that requires two lasers, but drastically cuts costs of machining parts. Lasers can be used to change the surface properties of a workpiece.\nThe appliance of laser beam machining varies depending on the industry. In light manufacturing the machine is used to engrave and to drill other metals. In the electronic industry laser beam machining is used for wire stripping and skiving of circuits. In the medical industry it is used for cosmetic surgery and hair removal.", "Engineering,_Manufacturing": 1.0000061989, "qwen": "Yes"}
{"id": "3526470", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=3526470", "title": "Mirror mount", "text": "A mirror mount is a device that holds a mirror. In optics research, these can be quite sophisticated devices, due to the need to be able to tip and tilt the mirror by controlled amounts, while still holding it in a precise position when it is not being adjusted. \nAn optical mirror mount generally consists of a movable front plate which holds the mirror, and a fixed back plate with adjustment screws. Adjustment screws drive the front plate about the axes of rotation in the pitch (vertical) and yaw (horizontal) directions. An optional third actuator often enables z-axis translation. \nPrecision mirror mounts can be quite expensive, and a notable amount of engineering goes into their design. Such sophisticated mounts are often required for lasers, interferometers, and optical delay lines.\nTypes of mirror mount.\nThe most common type of mirror mount is the kinematic mount. This type of mount is designed according to the principles of kinematic determinacy. Typically, the movable frame that holds the mirror pivots on a ball bearing which is set into a hole in the fixed frame. Ideally, this hole should be trihedral (pyramid-shaped). Often a conical hole is used due to easier manufacture. The frame is pivoted by means of two micrometers or fine-thread screws, tipped with steel ball bearings. One of these ball bearings rests in a V-groove, the other rests on a flat surface. On cheaper mounts, the flat surface may be simply the material of the mount. In more expensive mounts, the flat surface (and perhaps the hole and v-groove too) may be made out of a much harder material (often sapphire), set into the frame.\nThe reason for this strange mechanism is that the first ball (ideally) makes contact with the fixed frame at exactly three points, the second ball at two, and the third ball at just one. These six points of contact exactly constrain the six degrees of freedom for motion of the movable frame. This leads to precise movement of the frame when the micrometers or screws are turned, without unnecessary wobble or friction.\nA disadvantage of kinematic mounts is that the center of the mirror moves along its normal axis, when the mirror is rotated. This is because the center of rotation is the middle of the first ball bearing, not the center of the mirror. For optical cavities and interferometers, it is often desirable to be able to align the mirrors separately from adjustments to the length of the cavity. For these applications and others, a more sophisticated mount is required.\nOne way of eliminating this translation along the axis is to set the first ball on a fine-thread screw as well. By appropriate adjustment of all three screws, the mirror can be tilted in either direction without translation. The screws can by driven by a motor under computer control to make this seem to the operator like simple rotation about a virtual pivot point in the center of the mirror surface. The translation can instead be eliminated mechanically by using a gimbal mount, which uses two rings that each pivot about a line running through the center of the mirror. This gives kinematically correct two-axis rotation about the center of the mirror.\nWith both types of mount, springs are needed to keep the frame pressed against the ball bearings, unless the mount is designed to be used only in an orientation where gravity will keep the frame in place. Following the cantilever principle, a large mount allows finer control than a smaller one. The frames are ideally made of a light material, to make the resonant frequency of the structure high. This reduces vibration, since many common sources of vibration are relatively low frequency. For stability, the fixed frame is supported by a rigid mount that is securely bolted to a supporting surface. In a laboratory environment, this is typically an optical table. A shock can cause the mount to move away from the ball bearings, but because there are only 6, hard contacts, the mirror will return to the original position, preserving the alignment.\nThe mount itself has to avoid deformation of the mounted optics. Stress from mounting can introduce aberration in the light reflected from a mirror, or photoelasticity inside a lens. In some lasers the mirrors have to be easily replaced, in which case the mount needs to be designed to allow the mirror to be removed and replaced without losing the correct alignment.\nOperation.\nThe fine-thread screws show a slip and stick behaviour; when used manually, a torque is applied with two fingers until the thread slips a bit, then the new position is read on a scale. Inexpensive screws do long slips and lack a scale. Precision micrometers perform better and provide a scale for reference. When used remotely, an electric motor is used to apply short pulses of torque. The motor is firmly connected with the screw and the thread and nothing else so that the pulse is absorbed by friction. To read out the position electronically, a rotary encoder is attached. When the ball is not completely centered on the screw and the axis is not normal to the mirror surface (which is an explicit feature of some convenience mirror mounts), a small sinus movement of the mirror is overlaid onto the linear movement, which a controller could compensate for. For analog fine control (5 nm), piezos are built into the mobile frame.\nApplications.\nLaser cavity end mirrors need very precise alignment. Due to their low divergence laser beams need precise steering mirrors. For rapid prototyping on an optical table mirror mounts can be used to hold other elements besides mirrors, for example lenses often need to be aligned for minimal coma. Sometimes prisms only need two axes alignment and can be mounted on a mirror mount rather than a three-axis prism table.\nCritical phase matched crystals can be aligned and tuned precisely with a standard mirror mount. The same is true for small etalons, retarders and polarizers. Furthermore, mirror mounts using magnets instead of springs allow the mobile frame to be removed and later replaced in exactly the same position.", "Engineering,_Manufacturing": 0.9986256361, "qwen": "Yes"}
{"id": "53886302", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=53886302", "title": "Optomechatronics", "text": "In engineering, optomechatronics is a field that investigates the integration of optical components and technology into mechatronic systems. The optical components in these systems are used as sensors to measure mechanical quantities such as surface structure and orientation. Optical sensors are used in a feedback loop as part of control systems for mechatronic devices. Optomechatronics has applications in areas such as adaptive optics, vehicular automation, optofluidics, optical tweezers and thin-film technology.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "40896035", "revid": "11308236", "url": "https://en.wikipedia.org/wiki?curid=40896035", "title": "Total productive maintenance", "text": "Total productive maintenance (TPM) started as a method of physical asset management, focused on maintaining and improving manufacturing machinery in order to reduce the operating cost to an organization. After the PM award was created and awarded to Nippon Denso in 1971, the JIPM (Japanese Institute of Plant Maintenance), expanded it to include 8 Activities of TPM that required participation from all areas of manufacturing and non-manufacturing in the concepts of lean manufacturing.\nTPM is designed to disseminate the responsibility for maintenance and machine performance, improving employee engagement and teamwork within management, engineering, maintenance, and operations.\nThere are eight types of Activities in TPM implementation process:\nHistory.\nTotal productive maintenance (TPM) was developed by Seiichi Nakajima in Japan between 1950 and 1970. This experience led to the recognition that a leadership mindset engaging front line teams in small group improvement activity is an essential element of effective operation. The outcome of his work was the application of the TPM process in 1971. One of the first companies to gain from this was Nippondenso, a company that created parts for Toyota. They became the first winner of the PM prize. An internationally accepted TPM benchmark developed by the JIPM Seiichi Nakajima is therefore regarded as the father of TPM. The classic TPM process he developed consisting of 5 principles was later enhanced by the JIPM to incorporate many of the lessons of lean manufacturing and is referred to as Company-Wide TPM which consists of 8 principles/activities. The name \"Pillar\" is symbolically used as a structural support to the structure of TPM. The term \"activities\" is more appropriate since execution of these 8 activities is the process of TPM implementation.\nObjectives.\nThe goal of TPM is the improvement of equipment effectiveness through engaging those that impact on it in small group improvement activities. Total quality management (TQM) and total productive maintenance (TPM) are considered as the key operational activities of the quality management system. In order for TPM to be effective, the full participation of entire organisation from top to frontline operators is vital. This should result in accomplishing the goal of TPM: \"Enhance the volume of the production, employee morals, and job satisfaction.\"\nThe main objective of TPM is to increase the Overall Equipment Effectiveness (OEE) of plant equipment. TPM addresses the causes for accelerated deterioration and production losses while creating the correct environment between operators and equipment to create ownership.\nOEE has three factors which are multiplied to give one measure called OEE\nPerformance x Availability x Quality = OEE\nEach factor has two associated losses making 6 in total, these 6 losses are as follows:\nPerformance = (1) running at reduced speed – (2) Minor Stops\nAvailability = (3) Breakdowns – (4) Product changeover\nQuality = (5) Startup rejects – (6) Running rejects\nThe objective finally is to identify then prioritize and eliminate the causes of the losses. This is done by self-managing teams that solve problems. Employing consultants to create this culture is a common practice.\nPrinciples.\nThe eight pillars of TPM are mostly focused on proactive and preventive techniques for improving equipment reliability:\nWith the help of these pillars, we can increase productivity.\nManufacturing support.\nImplementation.\nFollowing are the steps involved by the implementation of TPM in an organization:\nAccording to Nicholas, the steering committee should consist of production managers, maintenance managers, and engineering managers. The committee should formulate TPM policies and strategies and give advice. This committee should be led by a top-level executive. Also a TPM program team must rise, this program team has oversight and coordination of implementation activities. As well, it's lacking some crucial activities, like starting with partial implementation. Choose the first target area as a pilot area, this area will demonstrate the TPM concepts. Lessons learned from early target areas/the pilot area can be applied further in the implementation process.\nDifference from TQM.\nTotal quality management and total productive maintenance are often used interchangeably. However, TQM and TPM share a lot of similarities but are considered as two different approaches in the official literature. TQM attempts to increase the quality of goods, services, and concomitant customer satisfaction by raising awareness of quality concerns across the organization.\nTQM is based on five cornerstones: The product, the process that allows the product to be produced, the organization that provides the proper environment needed for the process to work, the leadership that guides the organization, and commitment to excellence throughout the organization.\nIn other words, TQM focuses on the quality of the product, while TPM focuses on the losses that impede the equipment used to produce the products. By preventing equipment break-down, improving the quality of the equipment and by standardizing the equipment (results in less variance, so better quality), the quality of the products increases. TQM and TPM can both result in an increase in quality. However, the way of going there is different. TPM can be seen as a way to help to achieve the goal of TQM.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "5814476", "revid": "35246606", "url": "https://en.wikipedia.org/wiki?curid=5814476", "title": "Tombstone (manufacturing)", "text": "A tombstone, also known as a pedestal-type fixture, tooling tower, tooling column or fixture block, is a fixture of two or more sides, onto which are mounted parts to be manufactured. Tombstones are typically used in automated systems; parts are loaded onto the tombstone so that robots may operate on one part, flip the tombstone, and operate on the next part until all processes are completed, then transport the entire tombstone to the next station.\nThe first tombstone type fixture was patented in 1971 by the Vereinigte Flugtechnische Werke.\nTombstones are used in agile manufacturing to facilitate quick and easy installation, scalability and reconfiguration.", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "17182320", "revid": "1152226377", "url": "https://en.wikipedia.org/wiki?curid=17182320", "title": "Hardfacing", "text": "Hardfacing is a metalworking process where harder or tougher material is applied to a base metal. It is welded to the base material, and generally takes the form of specialized electrodes for arc welding or filler rod for oxyacetylene and gas tungsten arc welding welding. Powder metal alloys are used in (PTA) also called powder plasma welding and thermal spray processes like high-velocity oxygen fuel coating, plasma spray, spray and fuse, etc. Submerged arc welding, FCAW (Flux Core Arc Welding) and MIG (Metal Inert Gas) / MAG (Metal Active Gas) uses continuously fed wire varying in diameter depending on process and current. Strip cladding process uses strips from 50 mm wide to 125 mm with a thickness of 0.5mm. Open arc welding uses continuously fed tubular electrode which may or may not contain flux.\nHardfacing may be applied to a new part during production to increase its wear resistance, or it may be used to restore a worn-down surface. Hardfacing by arc welding is a surfacing operation to extend the service life of industrial components, preemptively on new components, or as part of a maintenance program. The result of significant savings in machine down time and production costs has meant that this process has been adopted across many industries such as steel, cement, mining, petrochemical, power, sugar cane and food. According to the results of an experimental study, the shielded metal arc welding and the gas metal arc welding hardfacing processes were effective in reducing the wear on the mouldboard ploughshare. With the shielded metal arc welding and gas metal arc welding hardfacing processes, the life span of the ploughshare was increased approximately 2 times [1].\nExtensive work in research has resulted in the development of a wide range of alloys and welding procedures. The optimum alloy selection is made considering the component service conditions and feedback of the service performance.\nFor each industrial application and wear phenomena, there is a welding electrode to provide wear resistance.\nHardfacing can be deposited by various welding methods:\nCommonly applied materials include cobalt-based alloys (such as stellite), nickel-based alloys, chromium carbide alloys and NOREM. Hardfacing is sometimes followed by hot stamping to refinish the part or add color or instructional information to the part. Foils or films can be used for a metallic look or other protection.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "10797690", "revid": "20725396", "url": "https://en.wikipedia.org/wiki?curid=10797690", "title": "Goldens' Foundry", "text": "Goldens' Foundry and Machine Co. is a privately held ductile iron and gray iron foundry with headquarters in Columbus, Georgia and additional facilities in Cordele, Georgia in the United States. It has operated continuously since 1882. Goldens' provides castings to a variety of industries, including agricultural, construction, power transmission, defense, and large vehicles. \nOperations.\nGoldens' Foundry began operations in Columbus, Georgia in 1882 as Goldens' Brothers, founded by 32-year-old Theodore Earnest \"Theo\" Golden and 24-year-old John Poitivent \"Porter\" Golden. At the beginning of 1889, Goldens' Brothers was incorporated, with the financial support of Abraham Illges, and renamed Goldens' Foundry and Machine Company.\nGoldens' is still owned and operated by descendants of the original three founders. George Golden Boyd, Sr., president and CEO, and George Golden Boyd, Jr., vice president of sales, continue to lead the family-run company to this day.\nThe foundry went through numerous upgrades, growing into a facility. With integrated core, molding, cleaning, and machining, and finishing facilities under one roof, Goldens' is able to provide a single-source resource to casting consumers.\nGoldens' employs more than 200 skilled workers at their Columbus location, and approximately 100 at their operation in Cordele.\nQuality Assurance\nGoldens' utilizes numerous techniques to ensure quality is maintained at both facilities. The company is ISO 9001-2015 certified by Lloyd's. Lean manufacturing principles are also in place throughout the facility, and 5S standards are in place in each department.\nColumbus casting facilities.\nIn Columbus, Casting operations in Goldens’ are supported by four Brown-Boveri coreless induction furnaces, coupled with 1200°F (650°C) preheating, and a comprehensive core shop employing isocure, shell and no-bake (air set). Steel and quality scrap are purchased from a variety of sources. \nLarge casting facility.\nGoldens’ Large Casting Facility utilizes a Heinrich Wagner Sinto automated molding machine. Using this (48x48 18/18) high pressure machine, ductile iron and gray iron casting capability includes the cost efficient manufacture of large castings. The Sinto incorporates the Seiatsu blow squeeze process, and provides opportunity to produce short run and high-volume orders.\nThe goal with a tight-flask machine such as this is to create near net-shape castings, reducing the need for machining and other processing operations.\nCentrifugal castings.\nGoldens' utilizes a specific centrifugal cast operation for adding iron liners to steel drums. In Goldens’ centrifugal casting process, molten iron is poured into a hollow cylindrical mold spinning on a horizontal or vertical axis at speeds generating 40 to 70 Gs of centrifugal force. This force distributes the molten metal, promotes directional solidification, and improves casting integrity by forcing impurities to the inside surface.\nCentrifugal casting at Goldens' is designed for specific product applications, as opposed to other foundries strictly devoted to the centrifugal process, such as steel pipe foundries. The centrifugal casting process was added in the late 1990s as a complement to the green sand mold processes already in place.\nNo bake molding.\nGoldens' added a fourth molding line, a no-bake sand operation in 2000. The manual molding operation allows production of much larger castings than the Sinto cope and drag machine, and is primarily utilized for Goldens' power transmission operations. This consists primarily of sheaves, pulleys, and sprockets.\nCordele casting facilities.\nGoldens' new second facility comprises the largest step in expanding output in the company's 125-year history. The facility, built in 2001, houses a brand new Savelli cope and drag (28x36’ 12/12) molding line with automatic core setter to create small to medium-sized ductile and gray iron castings. \nAlthough not as fast as many vertically parted molding machines, the Savelli is capable of making ~120 molds an hour. The new machine, with the expanded resources it provides, more than doubles the capacity of Goldens' casting production.\nThe facility also includes cleaning, finishing, and machining centers.\nThe building has previously housed two other foundries, Georgia Ductile and Wescast - Cordele. Both were foundries focused on supplying automotive parts for the US car industry.\nOperations at the new Goldens' facility began in May 2007.\nMachining operations.\nGoldens' machining facilities handle most operations their customers need. The operations primarily consist of turning, milling, and drilling operations, although operators perform a limited number of threading, painting, tapping, and sub-assembly operations.\nThe Columbus machining facility is larger than the Cordele facility, having been there since the late 1800s. The Columbus machining facility includes a larger variety of machines as well, while the Cordele facility currently only maintains horizontal milling and drilling machines.\nThe Columbus machining center uses horizontal milling and drilling machines with table sizes ranging from 400mm2 to 630mm2. Vertical machines range from 20\" x 39.5\" to 22\" x 44\".\nIndustries served.\nGoldens' serve a variety of industries, such as construction machinery, pumps and compressors, petroleum, mechanical power transmission, highway and off-highway trucks, farm machinery and equipment, and medical/surgical equipment. Goldens' utilizes both gray iron and ductile iron technology.\nReferences.\n Goldens' Foundry and Machine Co. website\n The American Foundry Society", "Engineering,_Manufacturing": 0.999980092, "qwen": "Yes"}
{"id": "59233311", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=59233311", "title": "Take-back system", "text": "A take-back system or simply takeback is one of the primary channels of waste collection, especially for e-waste, besides municipal sites. Take-back is the idea that manufacturers and sellers \"take back\" the products that are at the end of their lives. Take-back is aimed to reduce a business' environmental impacts on the earth and also increase efficiency and lower costs for their business models. \"Take-back regulations have targeted a wide array of products including packaging, batteries, automobiles, and electronics\" and economic value can be found from recycling or re-manufacturing such products. \"The programs benefit municipalities by lowering their overall waste disposal costs and reducing the burden on landfill sites\". Although for certain companies, the take-back system is mandatory under legislation, many do it voluntarily.\nTake-back can be split up into:\nIt can be further split into two types:\nRecycling.\nOne major option of the take-back system includes store retailers or producers taking back the products that have been distributed to their consumers in order to recycle the materials of these products. The take-back system encourages businesses to redesign their products into ones that are easily recyclable, reducing the burden that virgin materials have on the environment for the present and the future. This also gives companies an alternative supply of raw minerals.\nRe-manufacturing.\nThe other major option of the take-back system includes the store retailers or producers taking back their products in order to create new ones. This process uses the older products in order to restore it into products that are of the same quality as the new ones. By this process, companies save up to 85% of energy that would have been used to manufacture brand new products.\nEconomic effect.\nThe take-back system has shown economic effects for many companies that have adapted it. An example is Xerox, a company that has saved over $200 million from their take-back program in a year alone. The system encourages companies to create products that are easy to dissemble and re-manufacture in order to cut costs and generate revenue through taking back older products. In this way, companies can use older products that would have otherwise been thrown away in order to renovate them, allowing for them to be sold again just as Sprint has, in order to save over a billion dollars. In Wisconsin, the development of a take-back system created many new jobs, started a few companies, and had brought revenue from e-waste processing.\nEnvironmental impact.\nThe take-back system provides a more environmentally friendly system for those that inherit it. The system gives the responsibility of handling waste to the producer, meaning that they are to guarantee that their products are dealt with when they are at the end of their lives. By taking old products back, companies reduce their environmental footprint on the world as their products are influenced to become more easily recyclable. The system influences companies to redesign their products in ways that are more cost-effective when they recycle, reuse, or re-manufacture their products. Policies of the system can require companies into using a certain amount of recycled material in their products, which reduces the amount of recovered materials that end up in landfills or incineration.\nCircular economy.\nThe take-back system can be a main component to the business model that is called the circular economy. The circular economy is a plan for a business or company that aims to use and reduce their waste in order to become sustainable on their own. The take-back system allows for this model to work as it allows companies to recycle old products in order to become more environmentally friendly, where materials are used from these old products in order to use as resources and encourage sustainability. Not only that, but for most companies, the take-back system shows to be a more cost-effective system as it effectively minimizes waste management costs.\nImplementation of take-back systems.\nCollection.\nDue to a high cost in recycling but low amount of customer incentive, companies and countries refrain from adapting a take-back system. To fix this, e-waste could be taken back by the producers for donations, for re-manufacturing, or for upgrades.\nWaste regulation legislation and government help.\nWithout legislation, a prominent take-back system cannot be achieved because current e-waste regulation systems are \"limited to private recycling of high-value waste with only limited consumer participation\". Rules and regulations that would incentive and fix issues regarding to the dumping electronic waste into landfills and prevent the illegal exportation of electronic waste are important to achieve success in e-waste management. The government would need to support it by giving incentives and the correct infrastructure in order to create such a system.\nInitiatives.\n\"Initiatives refer to programs or schemes required to promote effective collection, recycling and disposal of e-waste\". Through these incentives, the government and producers of waste must promote e-waste management on their own by giving effort in collecting e-waste to recycle, renew, or reuse it.\nAwareness and responsibility.\nConsumers of the products must become aware to how managing their waste affects the environment and the lack of programs that help teach these aspects show to be big barriers to the effective management of waste. To manage the waste properly, consumers must begin to show responsibility in bringing in their e-waste while companies such as the producers of these products must be responsible for taking it back and dealing with it.\nGermany's take-back system.\nGermany had set in put a packaging ordinance on June 12, 1991. \"It specifies mandatory quotas for recycling for glass, paper/paperboard/carton, tin plate, aluminum, plastic, and composites\". The responsibility for handling waste was put onto the manufacturer and distributor. As a result of the ordinance, \"in 1993, the beginning of the mandatory quotas, compared to 1992, there were 500,000 fewer tons of packaging\" and \"From 1993 to 1994, paper packaging recycling increased from 55% to 70.6%\". The system showed to be a success, as it reduced waste and redesigned packaging to be more environmentally friendly simply from integrating a version of the take-back system.\nIssues.\nWhile the take-back system aims to create more eco-friendly businesses, there are reasons why it does not profoundly exist today. The main reason for this is the lack of incentives. Being that there are products such as cars and computers that are unappealing to transport, the consumer finds it troubling and unappealing to bring these products back. Also, since many consumers see refurbished products as inferior and do not trust them, it is unappealing for companies to re-manufacture their own products for reselling purposes and thus cannot profit from it. Without the appropriate subsidies, in some cases it becomes more beneficial for a company to use virgin materials as opposed to recycling methods as it is cheaper, swaying some away from the take-back system.", "Engineering,_Manufacturing": 0.9960644245, "qwen": "Yes"}
{"id": "1517745", "revid": "3980907", "url": "https://en.wikipedia.org/wiki?curid=1517745", "title": "Monocrystalline whisker", "text": "A monocrystalline whisker is a filament of material that is structured as a single, defect-free crystal. Some typical whisker materials are graphite, alumina, iron, silicon carbide and silicon. Single-crystal whiskers of these (and some other) materials are known for having very high tensile strength (on the order of 10–20 GPa). Whiskers are used in some composites, but large-scale fabrication of defect-free whiskers is very difficult.\nPrior to the discovery of carbon nanotubes, single-crystal whiskers had the highest tensile strength of any materials known, and were featured regularly in science fiction as materials for fabrication of space elevators, arcologies, and other large structures. Despite showing great promise for a range of applications, their usage has been hindered by concerns over their effects on health when inhaled.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "3765471", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=3765471", "title": "Hot runner", "text": "A hot runner system is an assembly of heated components used in plastic injection molds that inject molten plastic into the cavities of the mold. (The cavities are the part of the mold shaped like the parts to be produced.)\nBy contrast, a cold runner is simply a channel formed between the two halves of the mold, for the purpose of carrying plastic from the injection molding machine nozzle to the cavities. Each time the mold opens to eject the newly formed plastic parts, the material in the runner is ejected as well, resulting in waste. A hot runner system usually includes a heated manifold and a number of heated nozzles. The main task of the manifold is to distribute the plastic entering the mold to the various nozzles which then meter it precisely to the injection points in the cavities.\nHot runner advantages.\nHot runner systems were first developed and came into sporadic use in the early 60s with generally negative results. They gained popularity in the 80s and 90s as technological advancements allowed improved reliability and the escalation of plastic materials prices made hot runner systems more desirable and cost effective. Hot runners are fairly complicated systems, they have to maintain the plastic material within them heated uniformly, while the rest of the injection mold is being cooled in order to solidify the product quickly. For this reason they are usually assembled from components pre manufactured by specialized companies. \nA hot runner controller is a temperature controller used to control the temperature in the hot runner. This helps create the most consistent part(s).\nHot runners usually make the mold more expensive to manufacture and run, but allow savings by reducing plastic waste and by reducing the cycle time. (do not have to wait until the conventional runners freeze).", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "3765828", "revid": "1161099642", "url": "https://en.wikipedia.org/wiki?curid=3765828", "title": "1971–72 European Cup Winners' Cup", "text": "The 1971–72 season of the European Cup Winners' Cup football club tournament was won by Rangers, who defeated Dynamo Moscow in the final.\nPreliminary round.\nSecond leg.\n\"4–4 on aggregate; Austria Wien won on away goals.\"\n\"Hibernians won 3–2 on aggregate.\"\nFirst round.\nSecond leg.\n\"Barcelona won 7–1 on aggregate.\"\n\"Steaua București won 1–0 on aggregate.\"\n\"Liverpool won 3–2 on aggregate\".\n\"Bayern Munich won 7–1 on aggregate.\"\n\"Torino won 5–0 on aggregate.\"\n\"Austria Wien won 2–1 on aggregate\".\n\"Rangers won 2–1 on aggregate.\"\n\"Sporting CP won 7–0 on aggregate\".\n\"Åtvidaberg won 5–4 on aggregate\".\n\"Chelsea won 21–0 on aggregate\".\n\"Beerschot won 8–0 on aggregate\".\n\"2–2 on aggregate; BFC Dynamo won 5–4 on penalties.\"\n\"Sparta won 3–1 on aggregate\".\n\"Red Star Belgrade won 8–4 on aggregate\".\n\"Eskişehirspor won 4–0 on aggregate\".\n\"Dynamo Moscow won 3–2 on aggregate\".\nSecond round.\n1The second leg was originally 3–2 to Sporting after 90 minutes, and 4–3 to Sporting after extra time. The referee erroneously ordered a penalty shoot-out which Sporting won 3–0; UEFA later ruled that Rangers had won on away goals.\nSecond leg.\n\"Steaua București won 3–1 on aggregate.\"\n\"Torino won 1–0 on aggregate.\"\n\"6–6 on aggregate; Rangers won on away goals.\"\n\"BFC Dynamo won 6−2 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"1–1 on aggregate; Bayern Munich won on away goals.\"\n\"Rangers won 2–1 on aggregate.\"\n\"BFC Dynamo won 4−2 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Rangers won 3–1 on aggregate.\"\n\"2–2 on aggregate; Dynamo Moscow won 4–1 on penalties.\"", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "67651019", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=67651019", "title": "Laser polishing", "text": "Laser polishing, also referred to as laser re-melting, is a type of micro-melting process employed for improving surface quality of materials. As opposed to other conventional polishing processes, this process does not involve removal of materials from the workpiece surface. In this process, the laser is made incident on the workpiece to melt the surface till a certain depth, thus enabling subsequent betterment of surface parameters due to re-solidification of the melted material.\nLaser Polishing can be done at two levels - micro and macro levels. The workpiece material can be any metal or metals alloys, and can also be used to polish certain ceramics and glass.\nPrinciple and mechanism.\nThe aim of this process lies in melting a thin layer of the workpiece surface to reduce the average height of the peaks found on the surface asperities. The melting depth is strictly restricted to a certain degree of the asperity height to prevent any major microstructural changes deep in the workpiece material. This is hugely affected by the type of laser radiation, i.e. pulsed-radiation or continuous radiation, as well as the laser parameters, viz. laser power, feed rate or scanning velocity, laser beam diameter, and distance between source (or precisely laser focal point) and workpiece surface.\nThis process is widely researched for the application of surface reduction techniques on various materials. The two most general mechanisms are identified as Shallow Surface Melt (SSM) and Surface Over Melt (SOM).\nShallow Surface Melt (SSM).\nLiterature defines SSM region is formed due to dynamic behavior of the high-temperature metal liquid which is forced into micro-asperities essentially filling up the valleys present on the surface. The depth of the melted material is typically \"less\" than the peak-valley distance which can be affected by the laser parameters. The cited SEM image shows a clearly distinguishable laser polished surface without showing major side effects on the surrounding material, and can be used as a reference for understanding SSM mechanism.\nSurface Over Melt (SOM).\nIncreasing the energy density of the laser beam after a certain level will change how the melt-pool, or the melted material will behave. With gradual increase in the melt-pool thickness, it will exceed the peak-valley distance (or the asperity height) thus converting the entire metal surface into a melt-pool. Higher densities of the laser causes the molten material to be pulled away from the solidifying front, thus forming ripples on the metal surface.\nThus, laser polishing with this mechanism requires extensive study of the effect of the laser parameters to reduce the waviness on the final polished surface.\nMechanical properties of laser polished components.\nSince the workpiece surface is exposed to high temperature which establishes a huge thermal gradient along its cross-section, there are a few changes at the micro-structural level due to the material behavior at the surface. However, majority of the literature reports show little change in the overall material properties of the entire workpiece.\nSurface morphology and microstructure.\nThe laser polished surface has a huge improvement in terms of average surface roughness of the worked material. This can be attributed to uniform distribution of the melt-pool during rapid solidification, due to presence of laser pressure, gravity and surface tension. The treated layer is divided into 3 major zones: the re-melted layer, the heat affected zone and the original workpiece material. The near consistent re-melted layer has finer grains compared to rest of the material because of high cooling rate. This reduction in size from original can be explained as a result of \"grain boundary pinning\" due to presence of already present or fresh precipitates in the melted material. The fresh precipitates may sprout from the material matrix or maybe induced from surrounding environment.\nGoing down the material, there is the heat affected zone, which is not exposed to the laser beam, but is affected by the melt-pool formed on the surface. The grain sizes are coarser than the re-melted surface layer, but not as large as the original grain size that are found by going further down the material (typically in additively manufactured workpiece).\nTensile properties.\nThe polished surface has a significant increase in tensile strength, but the total elongation (till failure) reduces. As a case study, consider a polymer-metal composite with aluminum fibers and PLA as the matrix. The cited study shows an increase in tensile strength from 41.01 MPa to 50.47 MPa with a reduced maximum elongation from an initial 60.6% to 33.2%. This can be explained as the result of densification and improved adhesion between the matrix and fiber components. The outcome therefore is increased rigidity and reduced ductility material at the polished surface.\nFor this specific case, the workpiece is fabricated with Fused Deposition Modelling (FDM), an additive manufacturing method. Typically, all the additively manufactured components have defects throughout their matrix, viz. gas porosity, gap between deposited layers, inconsistent lamination of the deposited layers and low adhesion among layers. All of the aforementioned terms have related or unrelated reasons of formation which can be studied in depth, but are beyond scope of this summary. These defects become the failure sources or origin of damage induced in the composite. Due to laser polishing, the failure behavior of the composite changes because of combined elastoplastic behavior of the newly polished fiber and matrix at the workpiece surface. Furthermore, since melted surface material flows from peak to unfilled valleys, many defects are removed. This also causes re-bonding of the matrix-matrix as well as matrix-fiber essentially improving the tensile strength as well as dynamic mechanical properties by creating a much denser structure.\nThis can be mathematically explained by rule of mixtures, by assuming constant strain for matrix and continuous fiber composite and evaluating the tensile strength for different stages found in a composite stress-strain curve\nOther improvements can be seen on the polished surface are increased micro-hardness, wear resistance and corrosion resistance.\nFracture behavior.\nDepending on the material being polished the fracture mechanism vary vastly for pure metals, non-metals, alloys, polymers, ceramics, amorphous solids and composites. All of them show improved fracture resistance post laser polishing because of reduced defects and increased resistance to crack propagation. However, this performance is not universal, it is also affected by presence of defects within the unaffected workpiece material.\nThe improved fracture behavior can be quantified by defining the critical stress intensity factor (formula_1). Theoretically, this value is achieved when the nominal applied stress is equal to the crack propagation stress, and is calculated taking into fact Griffith criteria. The final derived equation for a plane stress condition is given by a square root of product of the material stiffness (formula_2) and the material toughness ( formula_3). As evident, with increase in material stiffness, the polished surface is bound to have increased toughness.\nA more in-depth study reveals role of more than just material stiffness in increase of the fracture resistance of the laser treated material. Multiple sources have described the effect of strain hardening (induced compression due to dislocation motion at elevated temperatures) and phase transformation within the material.\nConsider another case study of a silicon nitride engineering ceramic. The result of this study documents the change in surface hardness, surface crack length and the surface formula_4 (mode-1 formula_1) by using the Vickers indentation technique(s). The increase in surface hardness and formula_4 factor can be related to the induced residual compressive stress due to motion of dislocations at the elevated temperatures during the laser polishing process. These compressive stresses act against the externally applied tension, thus needing a certain threshold value in addition to the fracture stress (or crack propagation stress) to completely overcome the opposing stresses before crack initiation. Other observations include a reduction of crack length by 37% in the laser polished Si3N4, and induced anisotopy, which is further discussed in the cited reference.", "Engineering,_Manufacturing": 1.0000044107, "qwen": "Yes"}
{"id": "21036975", "revid": "10027499", "url": "https://en.wikipedia.org/wiki?curid=21036975", "title": "Rubber pad forming", "text": "Rubber pad forming (RPF) is a metalworking process where sheet metal is pressed between a die and a rubber block, made of polyurethane. Under pressure, the rubber and sheet metal are driven into the die and conform to its shape, forming the part. The rubber pads can have a general purpose shape, like a membrane. Alternatively, they can be machined in the shape of die or punch.\nRubber pad forming is a deep drawing technique that is ideally suited for the production of small and medium-sized series. Deep drawing makes it possible to deform sheet metal in two directions, which offers great benefits in terms of function integration, weight reduction, cleanability and such.\nThe disadvantage of regular deep drawing is that expensive tools consisting of an upper and lower mold are needed. Once these tools have been made, the variable costs are low, which makes regular deep drawing very suitable for large and very large numbers of products.\nTechnique.\nIn the rubber pad forming process only a milled lower die is required on which a metal plate is placed. Afterwards, the shape of the lower die is pressed in the plate with the rubber mold. In most cases, the contour, hole patterns and the like will be cut with a 3D laser cutter.\nThe simplicity of the rubber press tool causes tooling costs to be around 85 to 90% lower than those of regular deep drawing while the variable costs are higher. This combination makes rubber pad pressing very suitable for smaller and medium-sized series (up to 5,000-10,000 pieces per year), even though traditional cutting, lace, welding, finishing etc. is used more due to the unfamiliarity with rubber pad forming.\n\n380 Ton Rubber Pad Press\nRubber pad forming has been used in production lines for many years. Up to 60% of all sheet metal parts in the aerospace industry are fabricated using this process.\nThe most relevant applications are indeed in the aerospace field. It is frequently used in prototyping shops and for the production of kitchenware. For a decade, rubber pad pressing has developed greatly into a widely used technology for many industrial applications.\nPressing power.\nEnormous pressing forces are required for the rubber presses to work. In the Netherlands there are several rubber pad presses, of which the largest one has a press force of no less than 8,000 tons with a maximum surface area of 1.10x2.20m, these presses are used for very diverse industrial applications.\nWorldwide, presses are in use up to about 14,000 tonnes.\nPros and cons.\nIn summary, the benefits of rubber pad pressing are:\nAnd the disadvantages:\nDefinition.\nRubber pad forming can be accomplished in many different ways, and as technology has advanced, so have the applications for this simple process. In general, an elastic upper die, usually made of rubber, is connected to a hydraulic press. A rigid lower die, often called a form block, provides the mold for the sheeted metal to be formed to. Because the upper (male) die can be used with separate lower (female) dies, the process is relatively cheap and flexible. The worked metal is not worn as quickly as in more conventional processes such as deep drawing, however, rubber pads exert less pressure in the same circumstances as non-elastic parts, which may lead to less definition in forming, and rubber pads wear more quickly than steel parts.\nThe Guerin process.\nThe Guerin process, also called Guerin Stamping, is a manufacturing process used in the shaping of sheet metals. It is the oldest and most basic of the production rubber-pad forming processes. It was developed in the late 1930s by Henry Guerin, an employee of the Douglas Aircraft Co. in California. Thereafter, it was used extensively by all major aircraft manufacturers to shape the many complex shapes inherent in the design of aircraft.", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "21037206", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=21037206", "title": "Component engineering", "text": "Component engineering is an engineering discipline primarily used to ensure the suitability and testability of suitable components required to manufacture a larger product.\nThe term combines two ideas:\nComponent designer engineers design, oversee the production, and test components for machines used in many different industries, from aviation to manufacturing, IT, software, telecommunications, and many more.\nTo make machine parts that are reliable and effective, they are involved in various stages of production, starting from research and product development, to compliance and design, or might work on testing and installing components.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "21054129", "revid": "41438237", "url": "https://en.wikipedia.org/wiki?curid=21054129", "title": "Threading (manufacturing)", "text": "In manufacturing, threading is the process of creating a screw thread. More screw threads are produced each year than any other machine element. There are many methods of generating threads, including subtractive methods (many kinds of thread cutting and grinding, as detailed below); deformative or transformative methods (rolling and forming; molding and casting); additive methods (such as 3D printing); or combinations thereof.\nOverview of methods (comparison, selection, etc.).\nThere are various methods for generating screw threads. The method for any one application is chosen based on constraints—time, money, degree of precision needed (or not needed), what equipment is already available, what equipment purchases could be justified based on resulting unit price of the threaded part (which depends on how many parts are planned), etc.\nIn general, certain thread-generating processes tend to fall along certain portions of the spectrum from toolroom-made parts to mass-produced parts, although there can be considerable overlap. For example, thread lapping following thread grinding would fall only on the extreme toolroom end of the spectrum, while thread rolling is a large and diverse area of practice that is used for everything from microlathe leadscrews (somewhat pricey and very precise) to the cheapest deck screws (very affordable and with precision to spare).\nThreads of metal fasteners are usually created on a thread rolling machine. They may also be cut with a lathe, tap or die. Rolled threads are stronger than cut threads, with increases of 10% to 20% in tensile strength and possibly more in fatigue resistance and wear resistance.\nThread Milling has a better thread quality than tapping as it offers better chip evacuation. Tapping uses a tool the same size as the thread, forcing the chip through the thread for evacuation.\nSubtractive methods.\nThread cutting.\nThread cutting, as compared to thread forming and rolling, is used when full thread depth is required, when the quantity is small, when the blank is not very accurate, when threading up to a shoulder is required, when threading a tapered thread, or when the material is brittle.\nTaps and dies.\nA common method of threading is cutting with taps and dies. Unlike drill bits, hand taps do not automatically remove the chips they create. A hand tap cannot cut its threads in a single rotation because it creates long chips which quickly jam the tap (an effect known as \"crowding\"), possibly breaking it. Therefore, in manual thread cutting, normal wrench usage is to cut the threads 1/2 to 2/3 of a turn (180 to 240 degree rotation), then reverse the tap for about 1/6 of a turn (60 degrees) until the chips are broken by the back edges of the cutters. It may be necessary to periodically remove the tap from the hole to clear the chips, especially when a blind hole is threaded.\nFor continuous tapping operations (i.e., power tapping) specialized spiral point or \"gun\" taps are used to eject the chips and prevent crowding.\nSingle-point threading.\nSingle-point threading, also colloquially called single-pointing (or just thread cutting when the context is implicit), is an operation that uses a single-point tool to produce a thread form on a cylinder or cone. The tool moves linearly while the precise rotation of the workpiece determines the lead of the thread. The process can be done to create external or internal threads (male or female). In external thread cutting, the piece can either be held in a chuck or mounted between two centers. With internal thread cutting, the piece is held in a chuck. The tool moves across the piece linearly, taking chips off the workpiece with each pass. Usually 5 to 7 light cuts create the correct depth of the thread.\nThe coordination of various machine elements including leadscrew, slide rest, and change gears was the technological advance that allowed the invention of the screw-cutting lathe, which was the origin of single-point threading as we know it today.\nToday engine lathes and CNC lathes are the commonly used machines for single-point threading. On CNC machines, the process is quick and easy (relative to manual control) due to the machine's ability to constantly track the relationship of the tool position and spindle position (called \"spindle synchronization\"). CNC software includes \"canned cycles\", that is, preprogrammed subroutines, that obviate the manual programming of a single-point threading cycle. Parameters are entered (e.g., thread size, tool offset, length of thread), and the machine does the rest.\nAll threading could feasibly be done using a single-point tool, but because of the high speed and thus low unit cost of other methods (e.g., tapping, die threading, and thread rolling and forming), single-point threading is usually only used when other factors of the manufacturing process happen to favor it (e.g., if only a few threads need to be made, if an unusual or unique thread is required, or if there is a need for very high concentricity with other part features machined during the same setup.)\nThread milling.\nThreads may be milled with a rotating milling cutter if the correct helical toolpath can be arranged. This was formerly arranged mechanically, and it was suitable for mass-production work although uncommon in job-shop work. With the widespread dissemination of affordable, fast, precise CNC, it became much more common, and today internal and external threads are often milled even on work where they would formerly have been cut with taps, die heads, or single-pointing. Some advantages of thread milling, as compared to single-point cutting or taps and dies, are faster cycle times, less tool breakage, and that a left- or right-hand thread can be created with the same tool. Additionally, for large, awkward workpieces (such as a fire hydrant casting), it is simply easier to let the workpiece sit stationary on a table while all needed machining operations are performed on it with rotating tools, as opposed to rigging it up for rotation around the axis of each set of threads (that is, for the \"arms\" and \"mouth\" of the hydrant).\nThere are various types of thread milling, including several variants of \"form-milling\" and a combination of drilling and threading with one cutter, called \"thrilling\".\nOne main advantage against tapping, is that tapping only starts making a complete thread profile on the third thread, whereas thread milling will produce a complete thread profile from the top to the bottom.\nForm-milling uses either a single- or multiple-form cutter. In one variant of form-milling, the single-form cutter is tilted to the helix angle of the thread and then fed radially into the blank. The blank is then slowly rotated as the cutter is precisely moved along the axis of the blank, which cuts the thread into the blank. This can be done in one pass, if the cutter is fed to the full thread depth, or in two passes, with the first not being to the full thread depth. This process is mainly used on threads larger than . It is commonly used to cut large-lead or multiple-lead threads. A similar variant using a multiple-form cutter exists, in which the process completes the thread in one revolution around the blank. The cutter must be longer than the desired thread length. Using a multiple-form cutter is faster than using a single-form cutter but it is limited to threads with a helix angle less than 3°. It is also limited to blanks of a substantial diameter and no longer than .\nAnother variant of form-milling involves holding the cutter's axis orthogonally (no canting to the thread's helix angle) and feeding the cutter in a toolpath that will generate the thread. The part is usually a stationary workpiece, such as a boss on a valve body (in external thread milling) or a hole in a plate or block (in internal thread milling). This type of thread milling uses essentially the same concept as contouring with an endmill or ball-nose mill, but the cutter and toolpath are arranged specifically to define the \"contour\" of a thread. The toolpath is achieved either using helical interpolation (which is circular interpolation in one plane [typically XY] with simultaneous linear interpolation along a third axis [typically Z]; the CNC control model must be one that supports using the third axis) or a simulation of it using extremely small increments of 3-axes linear interpolation (which is not practical to program manually but can be programmed easily with CAD/CAM software). The cutter geometry reflects the thread pitch but not its lead; the lead (thread helix angle) is determined by the toolpath. Tapered threads can be cut either with a tapered multiple-form cutter that completes the thread in one revolution using helical interpolation, or with a straight or tapered cutter (of single- or multiple-form) whose toolpath is one or more revolutions but cannot use helical interpolation and must use CAD/CAM software to generate a contour-like simulation of helical interpolation.\nThe tooling used for thread milling can be solid or indexable. For internal threads, solid cutters are generally limited to holes larger than , and indexable internal thread cutting tools are limited to holes larger than . The advantage is that when the insert wears out it is easily and more cost effectively replaced. The disadvantage is the cycle time is generally longer than solid tools. Note that solid multiple-form thread cutting tools look similar to taps, but they differ in that the cutting tool does not have a backtaper and there is not a lead-in chamfer. This lack of a lead-in chamfer allows the threads to be formed within one pitch length of the bottom of a blind hole.\nThrilling.\nThrilling is the process of threading and drilling (accomplished in the reverse order) internal threads using a specialized cutting tool on a CNC mill. The cutting tool tip is shaped like a drill or center-cutting endmill, while the body has a thread-shaped form with a countersink cutter form near the shank. The cutter first plunges to drill the hole. Then the thread is circularly interpolated just like the multiple-form cutter described above. This tool drills, chamfers, and threads a hole all in one compact cycle. The advantage is this process eliminates a tool, tool-holder, and tool change. The disadvantage is that the process is limited to hole depth no greater than three times the diameter of the tool.\nHelical broaching (Punch Tap).\nA method of helical broaching was developed in the 2010s that shortens the toolpath of tapping. To a casual observer (without slow motion), it looks rather similar to traditional tapping but with faster movement into and out of the hole. It uses a specific tool geometry and toolpath to position rapidly, broach the thread in a single half-turn, and then retract rapidly, shortening the cycle time and consuming less energy. It reduces the cost of threading for any holes that can safely allow the two small fast-helix grooves that it leaves behind along with the thread, which could be true in many applications.\nThread grinding.\nThread grinding is done on a grinding machine using specially dressed grinding wheels matching the shape of the threads. The process is usually used to produce accurate threads or threads in hard materials; a common application is ball screw mechanisms. There are three types: \"center-type grinding with axial feed\", \"center-type infeed thread grinding\" and \"centerless thread grinding\". Center-type grinding with an axial feed is the most common of the three. It is similar to cutting a thread on a lathe with a single-point cutting tool, except the cutting tool is replaced with a grinding wheel. Usually a single ribbed wheel is used, although multiple ribbed wheels are also available. To complete the thread multiple passes are commonly required. Center-type infeed thread grinding use a grinding wheel with multiple ribs that is longer than the length of the desired thread. First, the grinding wheel is fed into the blank to the full thread depth. Then the blank is slowly rotated through approximately 1.5 turns while axially advancing through one pitch per revolution. Finally, the centerless thread grinding process is used to make head-less set screws in a similar method as centerless grinding. The blanks are hopper-fed to the grinding wheels, where the thread is fully formed. Common centerless thread grinding production rates are 60 to 70 pieces per minute for a long set screw.\nThread lapping.\nRarely, thread cutting or grinding (usually the latter) will be followed by thread lapping in order to achieve the highest precision and surface finish achievable. This is a toolroom practice when the highest precision is required, rarely employed except for the leadscrews or ballscrews of high-end machine tools.\nThreading with EDM.\nInternal threads can be electrical discharge machined (EDM) into hard materials using a sinker style machine.\nDeformative or transformative methods.\nThread forming and rolling.\nThread forming and thread rolling are processes for forming, rather than cutting, screw threads, with the former referring to creating internal threads and the latter external threads. In both of these processes threads are formed into a blank by pressing a shaped tool, commonly called a 'thread rolling die' against the blank, in a process similar to knurling. These processes are used for large production runs because typical production rates are around one piece per second. Forming and rolling produce no swarf and less material is required because the blank size starts smaller than a blank required for cutting threads; there is typically a 15 to 20% material savings in the blank, by weight. A rolled thread can be easily recognized on fasteners that were formed from an unstopped blank because the thread has a larger diameter than the blank rod from which it has been made; however, necks and undercuts can be cut or rolled onto blanks with threads that are not rolled, and some fasteners are made from blanks with a reduced shank in the region to be rolled to maintain a constant major diameter from thread to unthreaded shank. Unless faced off, the end threads of a rolled fastener have a cupped end, as the surplus material in the tapering down final threads collapses uniformly over the end of the blank.\nMaterials are limited to ductile materials because the threads are cold formed. However, this increases the thread's yield strength, surface finish, hardness, wear resistance, and fatigue strength due to conformance of the grain with the thread profile. Also, materials with good deformation characteristics are necessary for rolling; these materials include softer (more ductile) metals and exclude brittle materials, such as cast iron. Tolerances are typically ±0.001 in. (±0.025 mm), but tolerances as tight as ±0.0006 in (±0.015 mm) are achievable. Surface finishes range from 6 to 32 micro-inches.\nThere are four main types of thread rolling, named after the configuration of the dies: \"flat dies\", \"two-die cylindrical\", \"three-die cylindrical\", and \"planetary dies\". The flat die system has two flat dies. The bottom one is held stationary and the other slides. The blank is placed on one end of the stationary die and then the moving die slides over the blank, which causes the blank to roll between the two dies forming the threads. Before the moving die reaches the end of its stroke the blank rolls off the stationary die in a finished form. The two-die cylindrical process is used to produce threads up to in diameter and in length. There are two types of three-die processes; the first has the three dies move radially out from the center to let the blank enter the dies and then closes and rotates to roll the threads. This type of process is commonly employed on turret lathes and screw machines. The second type takes the form of a self-opening die head. This type is more common than the former, but is limited by not being able form the last 1.5 to 2 threads against shoulders. Planetary dies are used to mass-produce threads up to in diameter.\nThread forming is performed using a ', or ', which closely resembles a cutting tap without the flutes. There are \"lobes\" periodically spaced around the tap that actually do the thread forming as the tap is advanced into a properly sized hole. Since the tap does not produce chips, there is no need to periodically back out the tap to clear away chips, which, in a cutting tap, can jam and break the tap. Thus thread forming is particularly suited to tapping blind holes, which are tougher to tap with a cutting tap due to the chip build-up in the hole. Note that the tap drill size differs from that used for a cutting tap and that an accurate hole size is required because a slightly undersized hole can break the tap. Proper lubrication is essential because of the frictional forces involved, therefore a lubricating oil is used instead of cutting oil.\nWhen considering the blank diameter tolerance, a change in blank diameter will affect the major diameter by an approximate ratio of 3 to 1. Production rates are usually three to five times faster than thread cutting.\nThread casting and molding.\nIn casting and molding the threads are directly formed by the geometry of the mold cavity in the mold or die. When the material freezes in the mold, it retains the shape after the mold is removed. The material is heated to a liquid, or mixed with a liquid that will either dry or cure (such as plaster or cement). Alternatively, the material may be forced into a mold as a powder and compressed into a solid, as with graphite.\nAlthough the first thoughts that come to mind for most machinists regarding threading are of thread \"cutting\" processes (such as tapping, single-pointing, or helical milling), Smid points out that, when plastic bottles for food, beverages, personal care products, and other consumer products are considered, it is actually plastic molding that is the principal method (by sheer volume) of thread generation in manufacturing today. Of course, this fact highlights the importance of the moldmakers getting the mold just right (in preparation for millions of cycles, usually at high speed).\nCast threads in metal parts may be finished by machining, or may be left in the as-cast state. (The same can be said of cast gear teeth.) Whether or not to bother with the additional expense of a machining operation depends on the application. For parts where the extra precision and surface finish is not strictly necessary, the machining is forgone in order to achieve a lower cost. With sand casting parts this means a rather rough finish; but with molded plastic or die-cast metal, the threads can be very nice indeed straight from the mold or die. A common example of molded plastic threads is on soda (pop) bottles. A common example of die-cast threads is on cable glands (connectors/fittings).\nAdditive methods.\nMany, perhaps most, threaded parts have \"potential\" to be generated via additive manufacturing (3D printing), of which there are many variants, including fused deposition modeling, selective laser sintering, direct metal laser sintering, selective laser melting, electron beam melting, layered object manufacturing, and stereolithography. For most additive technologies, it has not been long since they emerged from the laboratory end of their historical development, but further commercialization is picking up speed. To date, most additive methods tend to produce a rough surface finish and tend to be restricted in the material properties that they can produce, and thus their earliest commercial victories have been in parts for which those restrictions were acceptable. However, the capabilities are continually growing.\nGood examples of threaded parts produced with additive manufacturing are found in the dental implant and bone screw fields, where selective laser sintering and selective laser melting have produced threaded titanium implants.\nCombinations of subtractive, additive, deformative, or transformative methods.\nOften subtractive, additive, deformative, or transformative methods are combined in whatever ways are advantageous. Such multidisciplinary manufacturing falls under classifications including rapid prototyping, desktop manufacturing, direct manufacturing, direct digital manufacturing, digital fabrication, instant manufacturing, or on-demand manufacturing.\nInspection.\nInspection of the finished screw threads can be achieved in various ways, with the expense of the method tailored to the requirements of the product application. Shop-floor inspection of a thread is often as simple as running a nut onto it (for male threads) or a bolt into it (for female threads). This is plenty good enough for many applications (e.g., MRO or hobbyist work), although it is not good enough for most commercial manufacturing. Higher-precision methods are discussed below.\nCommercial-grade inspection of screw threads can involve most of the same inspection methods and tools used to inspect other manufactured products, such as micrometers; vernier or dial calipers; surface plates and height gauges; gauge blocks; optical comparators; white light scanners; and coordinate-measuring machines (CMMs). Even industrial radiography (including industrial CT scanning) can be used, for example, to inspect internal thread geometry in the way that an optical comparator can inspect external thread geometry.\nConical micrometer anvils, specifically suited to resting on the sides of the thread, are made for various thread angles, with 60° being the most common. Mics with such anvils are usually called \"thread mics\" or \"pitch mics\" (because they directly measure the pitch diameter). Users who lack thread mics rely instead on the \"3-wire method\", which involves placing 3 short pieces of wire (or gauge pins) of known diameter into the valleys of the thread and then measuring from wire to wire with standard (flat) anvils. A conversion factor (produced by a straightforward trigonometric calculation) is then multiplied with the measured value to infer a measurement of the thread's pitch diameter. Tables of these conversion factors were established many decades ago for all standard thread sizes, so today a user need only take the measurement and then perform the table lookup (as opposed to recalculating each time). The 3-wire method is also used when high precision is needed to inspect a specific diameter, commonly the pitch diameter, or on specialty threads such as multi-start or when the thread angle is not 60°. Ball-shaped micrometer anvils can be used in similar fashion (same trigonometric relationship, less cumbersome to use). Digital calipers and micrometers can send each measurement (data point) as it occurs to storage or software through an interface (such as USB or RS-232), in which case the table lookup is done in an automated way, and quality assurance and quality control can be achieved using statistical process control.\nHistory.\nEach method of thread generation has its own detailed history. Therefore, a comprehensive discussion is beyond the scope of this article; but much historical information is available in related articles, including: \nCold-rolling.\nThe first patent for the cold rolling of screw threads was issued in 1836 to William Keane of Monroe, N.Y. However, the dies for rolling the threads onto the screw blanks were made of cast iron, which is brittle, so the machine was not successful.\nThe process languished until 1867, when Harvey J. Harwood of Utica, New York filed a patent for the cold-rolling of threads on wood screws. Further efforts to cold-roll threads on screws followed, but none seemed to meet with much success until Hayward Augustus Harvey (1824-1893) of Orange, N.J. filed his patents of 1880 and 1881. Charles D. Rogers of the American Screw Co. of Providence, Rhode Island made further refinements to the process of rolling threads onto screws.", "Engineering,_Manufacturing": 1.000005722, "qwen": "Yes"}
{"id": "2428399", "revid": "36701720", "url": "https://en.wikipedia.org/wiki?curid=2428399", "title": "Burr (cutter)", "text": "Burrs or burs (sometimes called rotary files) are small cutting tools; not to be confused with small pieces of metal formed from cutting metal, used in die grinders, rotary tools, or dental drills. The name may be considered appropriate when their small-sized head (3 mm diameter shaft) is compared to a bur (fruit seed with hooks) or their teeth are compared to a metal burr.\nDescription.\nBurrs are a rotary analog to files that cut linearly (hence their alternate name, rotary files). They are also in many ways comparable to endmills and router bits; a distinction is that the latter usually have their toolpath controlled by the machine, whereas burrs are often used freehand. However, there is substantial overlap in the use and toolpath control of these various classes of cutters, and e outcomes accomplished with them. For example, endmills can be used in routers, and burrs can be used like endmills in milling by CNC or manual machine tools. These are often used in CNC machining centers for removing burrs (the small flakes of metal) after a machining process.\nBurrs are spun quickly to maintain the ideal surface speed and cutting conditions (thousands or tens of thousands of RPM; often the top speed available on a given spindle). Because they are constructed of tungsten carbide, the cutters in the image can operate at higher speeds than comparable \"HSS\" cutters while still maintaining their cutting edges.\nBecause the cutting edges of burrs are so small, they can often be touched when spinning by a finger without cutting the skin, which flexes out of the way, although it would not be safe to pinch or grip them from two sides. Hard metal or ceramic workpieces cannot flex beyond the cutting edges, so the tools remove material from them. This characteristic makes burrs suitable for use in dentistry, as the tool will grind the hard enamel of teeth, yet leaves soft mouth tissues unharmed if the tool should unintentionally touch them.", "Engineering,_Manufacturing": 0.9999784231, "qwen": "Yes"}
{"id": "26699884", "revid": "43283345", "url": "https://en.wikipedia.org/wiki?curid=26699884", "title": "Embedded wafer level ball grid array", "text": "Embedded wafer level ball grid array (eWLB) is a packaging technology for integrated circuits. The package interconnects are applied on an artificial wafer made of silicon chips and a casting compound.\neWLB is a further development of the classical wafer level ball grid array technology (WLB or WLP: wafer level package). The main driving force behind the eWLB technology was to allow fanout and more space for interconnect routing.\nAll process steps for the generation of the package are performed on the wafer. This allows, in comparison to classical packaging technologies (e. g. ball grid array), the generation of very small and flat packages with excellent electrical and thermal performance at lowest cost. It is common for all WLB technologies, which are built on a silicon wafer, that the interconnects (typically solder balls) fit on the chip (so called fan-in design). Therefore only chips with a restricted number of interconnects can be packaged.\nThe eWLB technology allows the realization of chips with a high number of interconnects. The package is not created on a silicon wafer as for the classical wafer level package, but on an artificial wafer. Therefore a front-end-processed wafer is diced and the singulated chips are placed on a carrier. The distance between the chips can be chosen freely, but it is typically larger than on the silicon wafer. The gaps and the edges around the chips are now filled with a casting compound to form a wafer. After curing an artificial wafer containing a mold frame around the dies for carrying additional interconnect elements is created. After the build of the artificial wafer (the so-called \"reconstitution\") the electrical connections from the chip pads to the interconnects are made in thin-film technology, as for any other classical wafer level package.\nWith this technology any number of additional interconnects can be realized on the package in an arbitrary distance (fan-out design). Therefore, this wafer level packaging technology can also be used for space sensitive applications, where the chip area wouldn’t be sufficient to place the required number of interconnects at a suitable distance. The eWLB technology was developed by Infineon, STMicroelectronics and STATS ChipPAC Ltd. First components were brought into market mid of 2009 (mobile phone).", "Engineering,_Manufacturing": 0.999997139, "qwen": "Yes"}
{"id": "19977383", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=19977383", "title": "STEP-NC", "text": "STEP-NC is a machine tool control language that extends the ISO 10303 STEP standards with the machining model in ISO 14649, adding geometric dimension and tolerance data for inspection, and the STEP PDM model for integration into the wider enterprise. The combined result has been standardized as ISO 10303-238 (also known as AP238).\nSTEP-NC was designed to replace ISO 6983/RS274D G-codes with a modern, associative communications protocol that connects computer numerical controlled (CNC) process data to a product description of the part being machined.\nA STEP-NC program can use the full range of geometric constructs from the STEP standard to communicate device-independent toolpaths to the CNC. It can provide CAM operational descriptions and STEP CAD geometry to the CNC so workpieces, stock, fixtures and cutting tool shapes can be visualized and analyzed in the context of the toolpaths. STEP GD&T information can also be added to enable quality measurement on the control, and CAM-independent volume removal features may be added to facilitate regeneration and modification of the toolpaths before or during machining for closed loop manufacturing.\nMotivation.\nInput to a CNC in the ISO 6983/RS274D G-code control language is often machine-specific and limited to axis motion commands. The machine tool is given little or no information about the desired result of the machining.\nSTEP-NC allows more information about the machining process to be sent to the machine control and adds new information about the product being machined. This \"Smart Data for Smart Machining\" enables applications such as the following:\nCapabilities.\nSTEP-NC can communicate a complete machining process description to a machine tool control or between manufacturing software applications. The information handled by STEP-NC can be divided into the following general categories. The standard handles technology-specific parameters for milling and turning, and extensions for other technologies under development (see Future work).\nSTEP-NC can exchange the explicit toolpath descriptions in use today, and add part, stock, and fixture geometry, a description of the tools, geometric dimensions and tolerances, and PDM information. A STEP-NC file is difficult to edit by hand because it contains geometry descriptions but for large programs the file size can be smaller because STEP-NC uses a compressed XML format instead of ASCII codes.\nHistory.\nSTEP-NC is not the first attempt at providing better quality information to a CNC. The EIA 494 Basic Control Language (BCL) defined a control language that was portable and had toolpaths independent of machine geometry, but did not contain any of the other product model information found in STEP-NC.\nThe core of STEP-NC is the ISO 14649 model for CNC control developed\nby European ESPRIT and IMS STEP-NC projects begun in 1999. These were led by Siemens with contributions from RWTH Aachen University and the University of Stuttgart in Germany, Komatsu and FANUC in Japan, Heidenhain in Switzerland, and the Pohang University of Science and Technology in Korea. Models for the control of CNC milling and turning machines were published in 2005, and draft models exist for EDM and contour cutting.\nIntegration of the CNC model into STEP to produce ISO 10303-238 was done in the United States, under the NIST ATP Model Driven Intelligent Control of Manufacturing project, led by STEP Tools, Inc. with an industrial review board (IRB) consisting of Fortune 500 companies, CAD and CAM software developers, machine tool manufacturers, job shops and industry experts. STEP-NC AP238 was published in 2007.\nIn 2005 the OMAC STEP-NC Working Group hosted an AP238 testing forum in Orlando to demonstrate 5-axis parts machined using AP238 CC1 machine independent toolpaths. Four CAD/CAM systems produced AP238 machining programs for milling a 5-axis test part (an NAS 979 circle/diamond/square with an inverted NAS 979 cone test in the center). Each run on a pair of CNCs configured for completely different machine geometries (AB tool tilt vs. BC table tilt). In addition, Boeing cut parts on a variety of machines at their Tulsa facility and a machine at NIST in Gaithersburg.\nIn June 2006, a live 5-axis STEP-NC machining demonstration was hosted by Airbus at the Université Paul Sabatier Laboratoire de Génie mécanique in Toulouse. Further machining and measurement demonstrations were conducted in Ibusuki Japan in 2007.\nOn March 10–12, 2008, the STEP Manufacturing team (ISO TC184 SC4 WG3 T24) met in Sandviken and Stockholm, Sweden to demonstrate use of STEP-NC for feed and speed optimization, high-speed machining, tolerance-driven tool compensation and traceability. The participants in the demonstrations included Airbus/Univ. Bordeaux, Boeing, Eurostep, KTH Royal Institute of Technology, NIST, Sandvik Coromant, Scania, STEP Tools, and Univ. of Vigo.\nOn October 1–2, 2008, the STEP Manufacturing team met at the Connecticut Center for Advanced Technology, in Hartford, Connecticut to demonstrate closed-loop machining, feed optimization, and measurement using STEP-NC. The highlight of the meeting was the live 5-axis machining of a titanium impeller. Participants in the machining demonstration and other activities included Boeing, Connecticut Center for Advanced Technology, Concepts NRec, DMG, KTH Royal Institute of Technology, Mitutoyo, NIST, Sandvik Coromant, Scania, Siemens, and STEP Tools.\nThese participants and others continue to hold STEP-NC international implementation and testing events on a roughly six-month cycle. The demonstrations in 2009 focused on machining a Mold part at multiple sites from the same AP238 data including one part machined on a FANUC-developed STEP-NC control. At a meeting in Seattle the parts were then measured for accuracy using a CMM probe and a laser scanner.\nIn the first half of 2010, the testing activity focused on tool wear management and machining a part in multiple setups with multiple alternate machining plans for 3, 4 and 5-axis machining. The new test part was a gear box that must be machined on all six sides. The tool wear and consequent machine loads were predicted from the STEP-NC data and verified using a dynamometer. In the second half of 2010, the testing forum applied STEP-NC to set up compensation with on-machine measurement of part and fixture datums using a FaroArm portable measurement device.\nIn 2012, the testing focused on machine tool accuracy calculations, culminating in a demonstration in June at the KTH production engineering labs in Stockholm. The test case milled a forged blank for a Crown Wheel Gear on an older Mazak VQC 20. Accuracy data from the machine was combined with tool engagement information from the STEP-NC to predict the deflections, which were tested against actual machining results.\nIn 2014, CAM data exchange using STEP-NC was shown at IMTS 2014 with daily machining demonstrations hosted by Okuma. A base machining process for a mold part was created by Boeing and then sent to Sandvik and ISCAR for optimization, producing a STEP-NC description containing all three process options. All machining was done in titanium and a range of CAM software was used, with all results captured as STEP-NC.\nAt IMTS 2018, a team consisting of Airbus, Boeing, DMG MORI, Hyundai WIA, Renishaw, and Mitutoyo demonstrated Digital Twin manufacturing by combining STEP-NC model and process data with MTConnect machine tool status and Quality Information Format (QIF) metrology results.\nA second edition of AP238 was published in 2020, followed by a third edition in 2022 for model-based integrated manufacturing, with geometry, tolerance, and kinematics improvements first introduced by AP242.\nFuture work.\nWork continues within the ISO standard committees to extend STEP-NC to new technologies and to incorporate refinements discovered during use. Process models for new technologies are usually produced by the ISO TC184/SC1/WG7 committee. Models for Wire & Sink EDM and contour cutting of wood or stone are under investigation.\nWork on extending and integrating STEP-NC with the manufacturing enterprise takes place in the ISO TC184/SC4/WG3/T24 STEP Manufacturing Team. This group also works on extensions and refinements discovered during testing. A series of traceability extensions have been proposed for linking STEP-NC machining programs with sensor feedback and machine state information during execution.\nThe National Shipbuilding Research Program (NSRP) has also hosted work to implement a prototype that connects a shipyard design system to a plate cutting using STEP-NC. This work involved extending STEP-NC to steel plate cutting and marking using lasers and plasma torches.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "19980356", "revid": "27744084", "url": "https://en.wikipedia.org/wiki?curid=19980356", "title": "Superplastic forming", "text": "Superplastic forming is an industrial process used for creating precise and complex components out of superplastic materials.\nProcess.\nThe material is first heated up to promote superplasticity. For titanium alloys e.g. Ti 6Al 4V and some stainless steels this is around and for aluminium alloys e.g. AA5083 it is between 450 and 520 °C. In this state the material becomes soft so processes that are usually used on plastics can be applied, such as: thermoforming, blow forming, and vacuum forming. Inert gas pressure is applied on the superplastic sheet forcing it into a female die.\nAdvantages and disadvantages.\nThe major advantage of this process is that it can form large and complex workpieces in one operation. The finished product has excellent precision and a fine surface finish. It also does not suffer from springback or residual stresses. Products can also be made larger to eliminate assemblies or reduce weight, which is critical in aerospace applications. Lower strength required and less tooling costs. McDonnell Douglas utilized SPF design and production technology into the F-15 in the 1980s, while in Europe an example of application can be found in some Eurofighter Typhoon assemblies (e.g. engine bays panels, foreplanes, slats).\nThe largest disadvantage of the process is its slow forming rate. Cycle times vary from two minutes to two hours, therefore it is usually used in low volume production applications. Another disadvantage is the non-uniformity of the produced part thickness. Several methods are used to improve the thickness uniformity of SPF parts. One is to apply a designed varying gas pressure profile instead of a constant pressure. Another approach is to tailor the contact friction between the die surface and the superplastic sheet.", "Engineering,_Manufacturing": 1.0000085831, "qwen": "Yes"}
{"id": "40856568", "revid": "41049936", "url": "https://en.wikipedia.org/wiki?curid=40856568", "title": "Edwin Ruud", "text": "Edwin Ruud (9 June 1854 – 9 December 1932) was a Norwegian-American mechanical engineer and inventor who immigrated to the United States where he designed, sold, and popularized the tankless water heater. He was the founder and President of Ruud Manufacturing Company, now a division of Rheem Manufacturing Company.\nBiography.\nEarly life.\nEdwin Ruud was born in the parish of Askim in Østfold, Norway. He was educated in engineering at the Horten Technical School (\"Horten tekniske skole\") in Vestfold, Norway.\nThe Fuel Gas And Manufacturing Company.\nIn the 1880s, Ruud began working for George Westinghouse at the Fuel Gas and Manufacturing Company in Pittsburgh, Pennsylvania. Eight years after filing his first US patent, Ruud filed the first of five patents he would assign to Westinghouse's Fuel Gas and Manufacturing company.\nIn 1889, Ruud engineered a design for an automatic storage tank-type gas water heater that used a bottom gas heater and temperature controlled gas-valve. He later patented the design in 1890. In October 1890, he expanded on his first water heater design, under the Fuel Gas and Manufacturing Company.\nRuud Manufacturing Company.\nOn January 22, 1897, Ruud filed a patent separate from the Fuel Gas and Manufacturing Company for an Automatic Water Heater. His new design consisted of a cast iron shell, enclosing burners, heating surfaces (a coil of copper tubing through which water flows), and thermostat controlling gas-valves. The object of the design improvement was, \"to maintain the supply of water at the desired temperature at all times.\"\nWith this new design, Ruud left the Fuel Gas and Manufacturing Company to start Ruud Manufacturing, his own engineering and manufacturing shop where he began to manufacture and popularize in home, as well as commercial and industrial water heaters.\nRuud was issued his patent for the coiled tube Automatic Water Heater on September 6, 1898.\nRuud's business expanded as he popularized and improved on his instant water heater design. In 1908, Ruud Manufacturing acquired two local heating and plumbing firms. James Hay of the James Hay Company, heating and plumbing engineers, closed his business in order to operate as president of the Ruud Manufacturing Company in 1908. and J.H. Folsom of Folsom-Webster Co., heating and plumbing contracting firm, dissolved his partnership in Folsom-Webster Company in 1908 to serve as chief of the Cincinnati branch of the Ruud Manufacturing Company. By 1915, the Ruud Manufacturing Company had offices in Pittsburgh, Pennsylvania; Kalamazoo, Michigan; Toronto, Canada; and Hamburg, Germany.\nThe Ruud Instantaneous Automatic Water Heater.\nThe Thermal Valve Model, Type F, of the Ruud Instantaneous Automatic Water Heater is a design that allows the user to instantaneously heat water for on demand applications while not heating, thus saving fuel, when not in use. The Type F was able to use LP gas, natural gas, and gasoline, requiring only a change of burner spud orifices, and was manufactured in two variations, the \"Standard Pressure Heaters,\" designed to operate in conditions where pressure was at least twenty-five pounds per square inch (1.7 bar), and \"Low Pressure Heaters,\" where operational water pressure could be as low as four pounds per square inch (0.3 bar). Thermal Valve Model, Type F heaters were manufactured in four residential sizes reflective of their output in gallons per minute: 3, 4, 6, 8.\nIn 1915, there were approximately one-hundred-thousand of the Type F installed throughout The United States and Canada.\nRuud Heating and Air Conditioning Equipment.\nEdwin Ruud died in 1932 and his widow, Minna Kaufmann Ruud died in 1953. In 1959, the water heater arm of the Ruud Manufacturing Company was purchased by Rheem Manufacturing Company and continued operation as a division of Rheem.", "Engineering,_Manufacturing": 0.9990790486, "qwen": "Yes"}
{"id": "229103", "revid": "1132044674", "url": "https://en.wikipedia.org/wiki?curid=229103", "title": "Spot welding", "text": "Spot welding (or resistance spot welding) is a type of electric resistance welding used to weld various sheet metal products, through a process in which contacting metal surface points are joined by the heat obtained from resistance to electric current.\nThe process uses two shaped copper alloy electrodes to concentrate welding current into a small \"spot\" and to simultaneously clamp the sheets together. Work-pieces are held together under pressure exerted by electrodes. Typically the sheets are in the thickness range. Forcing a large current through the spot will melt the metal and form the weld. The attractive feature of spot welding is that a large amount of energy can be delivered to the spot in a very short time (approximately 10–100 milliseconds). This permits the welding to occur without excessive heating of the remainder of the sheet.\nThe amount of heat (energy) delivered to the spot is determined by the resistance between the electrodes and the magnitude and duration of the current. The amount of energy is chosen to match the sheet's material properties, its thickness, and type of electrodes. Applying too little energy will not melt the metal or will make a poor weld. Applying too much energy will melt too much metal, eject molten material, and make a hole rather than a weld. Another feature of spot welding is that the energy delivered to the spot can be controlled to produce reliable welds.\nProcess and equipment.\nSpot welding involves three stages; the first of which involves the electrodes being brought to the surface of the metal and applying a slight amount of pressure. The current from the electrodes is then applied briefly after which the current is removed but the electrodes remain in place for the material to cool. Weld times range from 0.01 sec to 0.63 sec depending on the thickness of the metal, the electrode force and the diameter of the electrodes themselves.\nThe equipment used in the spot welding process consists of tool holders and electrodes. The tool holders function as a mechanism to hold the electrodes firmly in place and also support optional water hoses that cool the electrodes during welding. Tool holding methods include a paddle-type, light duty, universal, and regular offset. The electrodes generally are made of a low resistance alloy, usually copper, and are designed in many different shapes and sizes depending on the application needed.\nThe two materials being welded together are known as the workpieces and must conduct electricity. The width of the workpieces is limited by the throat length of the welding apparatus and ranges typically from . Workpiece thickness can range from .\nAfter the current is removed from the workpiece, it is cooled via the coolant holes in the center of the electrodes. Both water and a brine solution may be used as coolants in spot welding mechanisms.\nIn the case of resistance spot welding, there are two main parts of the tooling system, the features of which fundamentally influence the whole process: the gun and its type, and the size and shape of the electrode. In such application, where the gun layout should be as rigid as possible due to the high applying forces (e.g. welding of thick materials), the C-type gun is widely used. As well as the high resulting rigidity, this arrangement leads to a high tooling flexibility, as the motion of the electrodes is collinear. Unlike the C-type, the so-called X-type arrangement provides less rigidity, although the reachable workspace is far larger than with the C-type, thus this layout is very common, where thin and flat objects are being processed (e.g. manufacturing of floor pan or roof panel). However, it offers less flexibility in terms of tooling, because the paths of the moving electrodes are not collinear (like the tips of a scissor), so a dome-shaped electrode tip should be used. \nElectrodes used in spot welding can vary greatly with different applications. Each tool style has a different purpose. Radius style electrodes are used for high heat applications, electrodes with a truncated tip for high pressure, eccentric electrodes for welding corners, offset eccentric tips for reaching into corners and small spaces, and finally offset truncated for reaching into the workpiece itself.\nCharacteristics.\nThe spot welding process tends to harden the material, causing it to warp. This reduces the material's fatigue strength, and may stretch the material as well as anneal it. The physical effects of spot welding include internal cracking, surface cracks and a bad appearance. The crack around the weld nugget will be extended under an external load or fatigue to produce a different type of failure. The chemical properties affected include the metal's internal resistance and its corrosive properties.\nWelding times are often very short, which can cause problems with the electrodes—they cannot move fast enough to keep the material clamped. Welding controllers will use a double pulse to get around this problem. During the first pulse, the electrode contact may not be able to make a good weld. The first pulse will soften the metal. During the pause between the two pulses, the electrodes will come closer and make better contact.\nDuring spot welding, the large electric current induces a large magnetic field, and the electric current and magnetic field interact with each other to produce a large magnetic force field too, which drives the melted metal to move very fast at a velocity up to 0.5 m/s. As such, the heat energy distribution in spot welding could be dramatically changed by the fast motion of the melted metal. The fast motion in spot welding can be observed with high-speed photography.\nThe basic spot welder consists of a power supply, an energy storage unit (e.g., a capacitor bank), a switch, a welding transformer, and the welding electrodes. The energy storage element allows the welder to deliver high instantaneous power levels. If the power demands are not high, then the energy storage element isn't needed. The switch causes the stored energy to be dumped into the welding transformer. The welding transformer steps down the voltage and steps up the current. An important feature of the transformer is it reduces the current level that the switch must handle. The welding electrodes are part of the transformer's secondary circuit. There is also a control box that manages the switch and may monitor the welding electrode voltage or current.\nThe resistance presented to the welder is complicated. There is the resistance of secondary winding, the cables, and the welding electrodes. There is also the contact resistance between the welding electrodes and the workpiece. There is the resistance of the workpieces, and the contact resistance between the workpieces.\nAt the beginning of the weld, the contact resistances are usually high, so most of the initial energy will be dissipated there. That heat and the clamping force will soften and smooth out the material at the electrode-material interface and make better contact (that is, lower the contact resistance). Consequently, more electrical energy will go into the workpiece and the junction resistance of the two workpieces. As electrical energy is delivered to the weld and causes the temperature to rise, the electrodes and the workpiece are conducting that heat away. The goal is to apply enough energy so that a portion of material within the spot melts without having the entire spot melt. The perimeter of the spot will conduct away much heat and keep the perimeter at a lower temperature. The interior of the spot has less heat conducted away, so it melts first. If the welding current is applied too long, the entire spot melts, the material runs out or otherwise fails, and the \"weld\" becomes a hole.\nThe voltage needed for welding depends on the resistance of the material to be welded, the sheet thickness and desired size of the nugget. When welding a common combination like 1.0 + 1.0 mm sheet steel, the voltage between the electrodes is only about 1.5 V at the start of the weld but can fall as low as 1 V at the end of the weld. This decrease in voltage results from the reduction in resistance caused by the workpiece melting. The open circuit voltage from the transformer is higher than this, typically in the 5 to 22 volt range.\nThe resistance of the weld spot changes as it flows and liquefies. Modern welding equipment can monitor and adjust the weld in real time to ensure a consistent weld. The equipment may seek to control different variables during the weld, such as current, voltage, power, or energy.\nWelder sizes range from 5 to 500 kVA. Micro spot welders, used in a variety of industries, can go down to 1.5 kVA or less for precision welding needs.\nIt is common for a spray of molten metal droplets (sparks) to be ejected from the area of the weld during the process.\nResistance spot welding generates no bright arc, so UV protection is not required. OSHA requires transparent face shields or goggles for splatter protection, but does not require any filter lens.\nApplications.\nSpot welding is typically used when welding particular types of sheet metal, welded wire mesh or wire mesh. Thicker stock is more difficult to spot weld because the heat flows into the surrounding metal more easily. Spot welding can be easily identified on many sheet metal goods, such as metal buckets. Aluminium alloys can be spot welded, but their much higher thermal conductivity and electrical conductivity requires higher welding currents. This requires larger, more powerful, and more expensive welding transformers.\nPerhaps the most common application of spot welding is in the automobile manufacturing industry, where it is used almost universally to weld the sheet metal to form a car. Spot welders can also be completely automated, and many of the industrial robots found on assembly lines are spot welders (the other major use for robots being painting).\nSpot welding is also used in the orthodontist's clinic, where small-scale spot welding equipment is used when resizing metal \"molar bands\" used in orthodontics.\nAnother application is spot welding straps to nickel–cadmium, nickel–metal hydride or Lithium-ion battery cells to make batteries. The cells are joined by spot welding thin nickel straps to the battery terminals. Spot welding can keep the battery from getting too hot, as might happen if conventional soldering were done.\nGood design practice must always allow for adequate accessibility. Connecting surfaces should be free of contaminants such as scale, oil, and dirt, to ensure quality welds. Metal thickness is generally not a factor in determining good welds.\nModifications.\n\"Projection welding\" is a modification of spot welding in which the weld is localized by means of raised sections, or projections, on one or both of the workpieces to be joined. Heat is concentrated at the projections, which permits the welding of heavier sections or the closer spacing of welds. The projections can also serve as a means of positioning the workpieces. Projection welding is often used to weld studs, nuts, and other threaded machine parts to metal plate. It is also frequently used to join crossed wires and bars. This is another high-production process, and multiple projection welds can be arranged by suitable designing and jigging.", "Engineering,_Manufacturing": 0.9999989271, "qwen": "Yes"}
{"id": "230283", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=230283", "title": "Wire bonding", "text": "Wire bonding is the method of making interconnections between an integrated circuit (IC) or other semiconductor device and its packaging during semiconductor device fabrication. Although less common, wire bonding can be used to connect an IC to other electronics or to connect from one printed circuit board (PCB) to another. Wire bonding is generally considered the most cost-effective and flexible interconnect technology and is used to assemble the vast majority of semiconductor packages. Wire bonding can be used at frequencies above 100 GHz.\nMaterials.\nBondwires usually consist of one of the following materials:\nWire diameters start from under 10 μm and can be up to several hundred micrometres for high-powered applications.\nThe wire bonding industry is transitioning from gold to copper. This change has been instigated by the rising cost of gold and the comparatively stable, and much lower, cost of copper. While possessing higher thermal and electrical conductivity than gold, copper had previously been seen as less reliable due to its hardness and susceptibility to corrosion. By 2015, it is expected that more than a third of all wire bonding machines in use will be set up for copper.\nCopper wire has become one of the preferred materials for wire bonding interconnects in many semiconductor and microelectronic applications. Copper is used for fine wire ball bonding in sizes from up to . Copper wire has the ability of being used at smaller diameters providing the same performance as gold without the high material cost.\nCopper wire up to can be successfully wedge bonded. Large diameter copper wire can and does replace aluminium wire where high current carrying capacity is needed or where there are problems with complex geometry. Annealing and process steps used by manufacturers enhance the ability to use large diameter copper wire to wedge bond to silicon without damage occurring to the die.\nCopper wire does pose some challenges in that it is harder than both gold and aluminium, so bonding parameters must be kept under tight control. The formation of oxides is inherent with this material, so storage and shelf life are issues that must be considered. Special packaging is required in order to protect copper wire and achieve a longer shelf life. Palladium coated copper wire is a common alternative which has shown significant resistance to corrosion, albeit at a higher hardness than pure copper and a greater price, though still less than gold. During the fabrication of wire bonds, copper wire, as well as its plated varieties, must be worked in the presence of forming gas [95% nitrogen and 5% hydrogen] or a similar anoxic gas in order to prevent corrosion. A method for coping with copper's relative hardness is the use of high purity [5N+] varieties.\nLong-term corrosion effects (Cu2Si) and other stability topics led to increased quality requirements when used in automotive applications \nPure gold wire doped with controlled amounts of beryllium and other elements is normally used for ball bonding. This process brings together the two materials that are to be bonded using heat, pressure and ultrasonic energy referred to as thermosonic bonding. The most common approach in thermosonic bonding is to ball-bond to the chip, then stitch-bond to the substrate. Very tight controls during processing enhance looping characteristics and eliminate sagging.\nJunction size, bond strength and conductivity requirements typically determine the most suitable wire size for a specific wire bonding application. Typical manufacturers make gold wire in diameters from and larger. Production tolerance on gold wire diameter is +/-3%.\nAlloyed aluminium wires are generally preferred to pure aluminium wire except in high-current devices because of greater drawing ease to fine sizes and higher pull-test strengths in finished devices. Pure aluminium and 0.5% magnesium-aluminium are most commonly used in sizes larger than .\nAll-aluminium systems in semiconductor fabrication eliminate the \"purple plague\" (brittle gold-aluminium intermetallic compound) sometimes associated with pure gold bonding wire. Aluminuim is particularly suitable for thermosonic bonding.\nIn order to assure that high quality bonds can be obtained at high production speeds, special controls are used in the manufacture of 1% silicon-aluminium wire. One of the most important characteristics of high grade bonding wire of this type is homogeneity of the alloy system. Homogeneity is given special attention during the manufacturing process. Microscopic checks of the alloy structure of finished lots of 1% silicon-aluminium wire are performed routinely. Processing also is carried out under conditions which yield the ultimate in surface cleanliness and smooth finish and permits entirely snag-free de-reeling.\nAttachment techniques.\nThe main classes of wire bonding:\nBall bonding usually is restricted to gold and copper wire and usually requires heat. For wedge bonding, only gold wire requires heat. Wedge bonding can use large diameter wires or wire ribbons for power electronics application. Ball bonding is limited to small diameter wires, suitable for interconnect application.\nIn either type of wire bonding, the wire is attached at both ends using a combination of downward pressure, ultrasonic energy, and in some cases heat, to make a weld. Heat is used to make the metal softer. The correct combination of temperature and ultrasonic energy is used in order to maximize the reliability and strength of a wire bond. If heat and ultrasonic energy is used, the process is called thermosonic bonding.\nIn wedge bonding, the wire must be drawn in a straight line according to the first bond. This slows down the process due to time needed for tool alignment. Ball bonding, however, creates its first bond in a ball shape with the wire sticking out at the top, having no directional preference. Thus, the wire can be drawn in any direction, making it a faster process.\nCompliant bonding transmits heat and pressure through a compliant or indentable aluminium tape and therefore is applicable in bonding gold wires and the beam leads that have been electroformed to the silicon integrated circuit (known as the beam leaded integrated circuit).\nManufacturing and reliability challenges.\nThere are multiple challenges when it comes to wire bond manufacturing and reliability. These challenges tend of be a function of several parameters such as the material systems, bonding parameters, and use environment. Different wire bond-bond pad metal systems such as Aluminium-Aluminium (Al-Al), Gold-Aluminium (Au-Al), and Copper-Aluminium (Cu-Al) require different manufacturing parameters and behave differently under the same use environments.\nWire bond manufacturing.\nMuch work has been done to characterize various metal systems, review critical manufacturing parameters, and identify typical reliability issues that occur in wire bonding. When it comes to material selection, the application and use environment will dictate the metal system. Often the electrical properties, mechanical properties, and cost are taken into account when making a decision. For example, a high current device for a space application might require a large diameter aluminium wire bond in a hermetically sealed ceramic package. If cost is a large constraint, then avoiding gold wire bonds may be a necessity. Some recent work has been done to look at copper wire bonds in automotive applications. This is only a small sampling, as there is a vast body of work reviewing and testing what material systems work best in different applications.\nFrom a manufacturing perspective, the bonding parameters play a critical role in bond formation and bond quality. Parameters such bond force, ultrasonic energy, temperature, and loop geometry, to name a few, can have a significant effect on bond quality. There are various wire bonding techniques (thermosonic bonding, ultrasonic bonding, thermocompression bonding) and types of wire bonds (ball bonding, wedge bonding) that affect susceptibility to manufacturing defects and reliability issues. Certain materials and wire diameters are more practical for fine pitch or complex layouts. The bond pad also plays an important role as the metallization and barrier layer(s) stackup will impact the bond formation.\nTypical failure modes that result from poor bond quality and manufacturing defects include: fracture at the ball bond neck, heel cracking (wedge bonds), pad liftoff, pad peel, overcompression, and improper intermetallic formation. A combination of wire bond pull/shear testing, nondestructive testing, and destructive physical analysis (DPA) can be used to screen manufacturing and quality issues.\nWire bond reliability.\nWhile wirebond manufacturing tends to focus on bond quality, it often does not account for wearout mechanisms related to wire bond reliability. In this case, an understanding of the application and use environment can help prevent reliability issues. Common examples of environments that lead to wire bond failures include elevated temperature, humidity, and temperature cycling.\nUnder elevated temperatures, excessive intermetallics (IMC) growth can create brittle points of fracture. Much work that has been done to characterize the intermetallic formation and aging for various metal systems. This not a problem in metal systems where the wire bond and bond pad are the same material such as Al-Al. This does become a concern in dissimilar metal systems. One of the most well known examples is the brittle intermetallics formed in gold-aluminium IMCs such as purple plague. Additionally, diffusion related issues, such as Kirkendall voiding and Horsting voiding, can also lead to wire bond failures.\nUnder elevated temperature and humidity environments, corrosion can be a concern. This is most common in Au-Al metal systems and is driven by galvanic corrosion. The presence of halides such as chlorine can accelerate this behavior. This Au-Al corrosion is often characterized with Peck's law for temperature and humidity. This is not as common in other metal systems.\nUnder temperature cycling, thermomechanical stress is generated in the wire bond as a result of coefficient of thermal expansion (CTE) mismatch between the epoxy molding compound (EMC), the leadframe, the die, the die adhesive, and the wire bond. This leads to low cycle fatigue due to shear or tensile stresses in the wire bond. Various fatigue models have been used to predict the fatigue life of wire bonds under such conditions.\nProper understanding of the use environment and metal systems are often the most important factors for increasing wire bond reliability.\nTesting.\nWhile there are some wire bond pull and shear testing techniques, these tend to be applicable for manufacturing quality rather than reliability. They are often monotonic overstress techniques, where peak force and fracture location are the critical outputs. In this case the damage is plasticity dominated, and does not reflect some wearout mechanisms that might be seen under environmental conditions.\nWire pull testing applies an upward force under the wire, effectively pulling it away from the substrate or die. The purpose of the test is as MIL-STD-883 2011.9 describes it: \"To measure bond strengths, evaluate bond strength distributions, or determine compliance with specified bond strength requirements\". A wire can be pulled to destruction, but there are also non-destructive variants whereby one tests whether the wire can withstand a certain force. Non-destructive test methods are typically used for 100% testing of safety critical, high quality and high cost products, avoiding damage to the acceptable wired bonds tested.\nThe term wire pull usually refers to the act of pulling a wire with a hook mounted on a pull sensor on a bond tester. However, to promote certain failure modes, wires can be cut and then pulled by tweezers, also mounted on a pull sensor on a bond tester. Usually wires up to 75 μm diameter (3 mil) are classified as thin wire. Beyond that size, we speak about thick wire testing.", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "53518564", "revid": "41504616", "url": "https://en.wikipedia.org/wiki?curid=53518564", "title": "Helmz", "text": "Helmz (stylized as HELMS) is a sports bicycle from Bridgestone Cycle Co., Ltd. jointly developed with fashion brand narifuri.\nOverview.\nBridgestone Cycle's 60th anniversary model was developed as \"bicycle to be a part of fashion\" with narifuri taking charge in frame design and concept establishment. It is made with an \"approach to create focus on design \". The model was announced in 2009 and was sold starting in 2010.\nThe name HELMZ was taken from the English term \"helm.\"\nCustom-designed original parts were made for HELMZ, by Japanese cycle part brands such as NITTO, MKS Pedal, and Sugino. Japanese oriented brand parts were selected carefully to minimize the use of Shimano parts.\nThese original parts of HELMZ are sold as aftermarket cycle products. The entire sales plan, including the package design of selling boxes and POP, was awarded the Minister of Economy Award and Planning Award in 42nd JPM Creative Design Show in 2012. SR1 received Good Design award in 2014.\nTechnical features.\nAir pressure formed aluminum frame.\nThe frame was based on a Top tube, sloped, low-front design from narifuri and was manufactured using superplastic forming) which molds the frame by inflating high air pressure in the 7005 aluminum pipe. Bridgestone cycle usually used this manufacturing method to improve riding performance, but in HELMZ it was necessary to realize the design.\nWheels.\nThe texture and rim height differ in front and rear wheels. The front wheel is silver with 35mm rim height. The rear wheel is black with 38 mm rim height. Models with high-performance sports wheels were launched afterward.\nThumb shifter.\nFor models with gear shifts, the Thumb shifter was selected. This shifter is operated with the thumb unlike the typical modern sports bicycle push bar mechanical shift.\nOriginal aftermarket parts.\nHlmz original aftermarket parts were released on 2012. Stem, handle bar, saddle, wheels, gear cranks, and most other original parts were sold on market as aftermarket parts.\nBelt drive.\nThe belt drive equipped models, SR1 and S10, were introduced in 2013. These models were an update of Bridegestone's belt drive experience from 1980, \"SSSD\" (Selectable SS Solld Drive). The new belt drives were made out of carbon instead of kevlar making the belts lighter and more flexible.\nModels.\nFrame shape and concepts have not been changed since its first announcement except for the new sizes being set.\nCollaboration.\nStar Wars.\nCollaborating with Star Wars, Helmz released two 5 year anniversary models in different colors. The Galactic Empire model is black based with blue, while the Rebel Alliance model is Silver based with red. The bikes were hand painted at the Bridgestone Cycle headquarter factory.\nAwards.\n2013 Planning: JPM Minister of Economy Award in 42nd JPM Creative Design Show for Year 2012\n2014 SR1: Good Design award 2014 \n2016 SR1: selected as \"JAPANESE DESIGN TODAY 100\" in Singapore ", "Engineering,_Manufacturing": 0.9743747711, "qwen": "Yes"}
{"id": "53544538", "revid": "8766034", "url": "https://en.wikipedia.org/wiki?curid=53544538", "title": "Pulau Indah Industrial Park", "text": "Pulau Indah Industrial Park (PIIP) located in Klang District, Selangor, Malaysia is 3,500 acres industrial area which are occupied by business like manufacturing, logistics and warehousing.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "31766888", "revid": "237572", "url": "https://en.wikipedia.org/wiki?curid=31766888", "title": "Punching machine", "text": "A punching machine is a machine tool for punching and embossing flat sheet-materials to produce form-features needed as mechanical element and/or to extend static stability of a sheet section.\nCNC punching.\nPunch presses are developed for high flexibility and efficient processing of metal stampings. The main areas of application are for small and medium runs. Those machines are typically equipped with a linear die carrier (tool carrier) and quick change tools. Today the method is used where the application of lasers are inefficient or technically impractical. CNC is the abbreviation of Computer Numerically Controlled.\nPrinciple of operation.\nAfter programming the work pieces and entering length of bars the control automatically calculates the maximum number of pieces to be punched (for example, 18 pieces of a bar of 6000 mm). Once the desired number of work pieces is entered, the bar is pushed toward the stop. The machine is fully automated once the production process is launched.\nThe third CNC axis always moves the cylinder exactly over the tool, which keeps the wear on the bearings and tools to a minimum. All pieces are sent down a slat conveyor and are pushed sideways on a table. Any scrap is carried to the end of the conveyor and dropped into a bin. Different workpieces can be produced within one work cycle to optimize production.\nProgramming.\nProgramming is done on a PC equipped with appropriate software that can be part of the machine or a connected external workstation. For generating a new program engineering data can be imported or pasted per mouse and keyboard. Through a graphic and menu-driven user interface previous CNC programming skills are not required. All the punches in a work piece are shown on the screen making programming mistakes easily detected. Ideally each program is stored in one database, so it is easy to recover them by search and sort functions. When selecting a new piece, all the necessary tooling changes are displayed. Before transferring it to the control unit the software scans each program for possible collisions. This eliminates most handling errors.\nTool change system.\nThe linear tool carrier (y-axis) has several stations that hold the punching tools and one cutting tool. Especially for flexibility and efficient processing are set up times a crucial cost factor. Downtimes should be reduced to a minimum. Therefore, recent tool systems are designed for fast and convenient change of punches and dies. They are equipped with a special plug-in system for a quick and easy change of tools.\nThere is no need to screw anything together. The punch and die plate are adjusted to each other automatically Punches and dies can be changed rapidly meaning less machine downtime.\nNetworking with the whole production line.\nA lot of organizational effort and interface management is saved, if the CNC punch press is connected to the previous and subsequent process. For a connection to other machines and external workstations corporate interfaces have to be established.\nIntegration of further production steps.\nBesides punching, machines of the high end class can be equipped with special functions. For example:", "Engineering,_Manufacturing": 1.0000050068, "qwen": "Yes"}
{"id": "42870676", "revid": "45708962", "url": "https://en.wikipedia.org/wiki?curid=42870676", "title": "Stencil printing", "text": "Stencil printing is the process of depositing solder paste on the printed wiring boards (PWBs) to establish electrical connections. It is immediately followed by the component placement stage. The equipment and materials used in this stage are a stencil, solder paste, and a printer.\nThe stencil printing function is achieved through a single material namely solder paste which consists of solder metal and flux. Paste also acts as an adhesive during component placement and solder reflow. The tackiness of the paste enables the components to stay in place. A good solder joint is one where the solder paste has melted well and flowed and wetted the lead or termination on the component and the pad on the board.\nIn order to achieve this kind of a solder joint, the component needs to be in the right place, the right volume of solder paste needs to be applied, the paste needs to wet well on the board and component, and there needs to be a residue that is either safe to leave on the board or one that can easily be cleaned.\nThe solder volume is a function of the stencil, the printing process and equipment, solder powder, and rheology or the physical properties of the paste. Good solder wetting is a function of the flux.\nInputs.\nInputs to the process can be classified as design input, material input and process parameter input. The output of the process is a printed wiring board that meets the process specification limits. These specifications usually are consistent solder paste volume and height, and printed solder paste aligned on the PWB pads. This determines the process yield.\nIn electronic design automation, the solder paste mask and thus the stencil is typically defined in a layer named codice_1/codice_2 aka codice_3/codice_4, codice_5/codice_6, codice_7/codice_8, or codice_9/codice_10 (EAGLE), codice_11/codice_12 (KiCad), codice_13/codice_14 (TARGET), codice_15/codice_16 (OrCAD), codice_17/codice_18 (PADS), codice_19/codice_20 (WEdirekt), codice_21/codice_22 (Gerber and many others). Some (less common) EDA software does not treat the solder paste mask as a regular part of a PCB's layer stack, in which case the paste mask must be derived from the solder stop mask.\nFor improved accuracy, stencils traditionally were often mounted in proprietary aluminum frames of various kinds. Today, the usage of quick mount systems is more common at least for low volume batches, mounting the stencil pneumatically or mechanically. For this the stencil needs additional perforations for alignment following one of several mount system standards including QuattroFlex, ZelFlex, ESSEMTEC, PAGGEN, Metz, DEK VectorGuard, Mechatronic Systems and others.\nPrinting process.\nThe process begins with loading the board into the printer. The internal vision system aligns the stencil to the board, after which the squeegee prints the solder paste. The stencil and board are then separated and unloaded. The bottom of the stencil is wiped about every ten prints to remove excess solder paste remaining on the stencil.\nA typical printing operation has a speed of around 15 to 45 seconds per board. Print head speed is typically 1 to 8 inches per second. The printing process must be carefully controlled. Misalignment of motion from the reference results in several defects, hence the board must be secured correctly before the process begins. A snugger and vacuum holders are used to secure the X and Y axes of the board. Vacuum holders must be carefully used, as they may affect the pin-in-paste printing process if not secured properly.\nThe longest process is the printing operation, followed by the separation process. Post print inspection is crucial and is usually performed with special 2D vision systems on the printer or separate 3D systems.\nPrinted wiring boards.\nDesign.\nVision systems in the stencil printing machines use global fiducial marks for aligning the PWB. Without these fiducials the printer would not print the solder paste in exact alignment with the pads. The PWB should have close dimensional tolerances so that it mates to the stencil. This is necessary to achieve the required alignment of solder blocks on the pads.\nMasking.\nThe required accuracy in alignment can also be achieved by controlling the flow of solder on the PWB during reflow soldering. For this purpose, the space between the pads is often coated with a solder mask. The solder mask materials have no affinity to the molten solder and hence, no positive bonding is formed between them as the solder solidifies. This process is often referred to as \"Solder masking\". The mask must be centered correctly. The mask protects the PWB against oxidation, and prevents unintended solder bridges from forming between closely spaced solder pads.\nAlso the height of the solder mask should be lower than the pad height to avoid gasketing problems. If the height of the solder mask is greater than that of the pad, then some of the solder paste would settle in the empty space between the mask and the pad. This is what is referred to as gasketing. It is a seal that fills the space between two surfaces to prevent leakages. Gasketing is a problem as the excess solder paste around the pad may be more than a nuisance factor for circuits having very small line spacing.\nFinishing.\nThe pads on the PWB are made of copper and are susceptible to oxidization. Surface oxidization on the copper will inhibit the ability of the solder to form a reliable joint. To avoid this unwanted effect, all exposed copper is protected with a surface finish.\nAperture fill and release.\nThe core of a well printed PWB lies in the fill and release of solder paste into the aperture. When the stencil is in contact with the PWB, solder paste is applied over the top surface of the stencil using a squeegee. This causes the aperture to fill with solder paste. The PWB is then lowered from the stencil. The amount of solder paste which is released from the stencil apertures and transferred to the PWB pads, determines whether or not the print is good. Ideally, all volumes of solder paste should be equal to the volume of the corresponding stencil aperture. In reality however, this is never the case. Hence, a print is considered to be good if a certain fraction of the paste is released. One way of quantifying print performance is to calculate the \"transfer efficiency\". This is mathematically stated as:\nIn the above expression, the theoretical maximum volume is simply the open volume of the stencil aperture. Ideally, a transfer efficiency of 1 is desired. In reality however, greater the transfer efficiency, better is the print.\nNow in order to get the aperture full of paste requires sufficient flow rate and sufficient fill time. Apertures which are not completely filled will not release paste onto the board, which results in clogged stencils and defective solder joints.\nSolder paste release is determined by the separation speed of the board from the stencil. The adhesion of the paste to the board has to provide the shearing force to overcome the adhesion of the paste to the stencil walls. This hydrodynamic shearing force depends on the separation speed.\nStencils.\nStencils are used to print solder paste on the PCB. They are often made of stainless steel or nickel and are manufactured by different processes described below.\nManufacturing processes.\nLaser cutting.\nThe use of laser technology allows having tighter tolerances and greater accuracy.\nThe aperture walls can be smoothed through electro-polishing and/or nickel plating. The laser cutting process results in trapezoidal apertures that can create better solder paste release characteristics.\nThe repeatability of dimensions in laser-cut stencils is generally better than that of chemical etching. With laser cutting, there are no photo films requiring precise alignment or protection from moisture.\nE-FAB stencil.\nThis stencil is formed by the process of electroforming nickel, hence the name E-FAB. The nickel has better wear characteristics than steel and electroforming creates smooth tapered aperture walls. The process also creates a ridge along the bottom of the stencil that can improve stencil-to-board gasketing and result in more consistent solder paste release.\nStencil design.\nDue to the need for fine pitch components, as the size of the aperture becomes smaller and smaller, they become “tall-narrow” apertures. In such cases, the apertures may be filled with solder paste but not completely released, or sometimes not even completely filled and hence get no deposits. In order to counter this problem, aperture walls are made as smooth as possible. Also, molecular layer nano coatings are put on the stencil walls so that the solder paste does not stick.\nConsistent fill and release is the most important output of stencil printing. When the stencil is down on the board, paste is filling the aperture and it's in contact with the pad and walls of the stencil. The contact is judged by taking the ratio of these areas i.e. the ratio of the area of the pad to the area of the walls. This is called \"area ratio\".\nThe information about the standards for stencil design is available at IPC Specification 7525 and other standards. In general, including stencils with tall and narrow apertures, an area ratio greater than 0.66 is recommended.\nIllustrations of the various dimensions:\nFor fine pitch stencils (smaller 20 mils pitch, 10 mils aperture), even with a 5 mils stencil, which is the most commonly used stencil thickness, the area ratio is below 1.5. This necessitates the use of a thinner stencil.\nFor BGA/CSP and other very small apertures, the area ratio is used. It should be greater than 0.66, as this ensures a high probability of good fill and release. An area ratio below 0.66 would mean a much less reliable process.\nExamples of area ratios for BGAs:\nAperture size should be smaller than the pad size to avoid the excess solder paste or production of solder balls. A 10 to 20% reduction in aperture size as compared to the pad size is typical to minimize solder balls. Solder balls can result in malfunctioning of the electric circuit.\nOther considerations.\nStep down stencils.\nA PCB may need varying amounts of solder paste to be applied depending upon the design and size of components. Applying a uniform maximum level of solder may not be a good solution in this case, as these stencils often find use when \"pin and paste\" technology (i.e., printing solder paste into through-holes to avoid wave soldering) and components of significantly different pitch are used in the same PWB. For this purpose, to achieve a varying solder amount, step down stencils are used.\nSolder paste stencil life.\nIdeally, a solder paste should have, at minimum, a 4-hour stencil life. The stencil life is defined as a time period in which there will be no significant change in the solder paste material characteristics. A solder paste with a longer stencil life will be more robust in the printing process. Actual stencil life for a paste should be determined from the manufacturers' specifications and on-site verification.\nHandling and storage of stencils.\nTo improve the life and performance of stencils, they must be cleaned after use by removing any solder paste on them or within the apertures. The cleaned stencils are stored away in a protective area. Before usage, stencils are inspected for wear or damage.\nStencils are typically identified by job numbers to reduce the risk of mishandling or misplacing.\nSqueegee.\nSqueegees are used to spread solder over the stencil and to fill all apertures consistently. Squeegees come in two different types based either on metal or polyurethane. Metal squeegees are preferred over polyurethane. They produce very consistent solder volumes and are resistant to scooping the solder paste out of the apertures when printing. In addition, they have better wear characteristics, leading to longer life.\nCommon difficulties.\nInsufficient solder paste.\nInsufficient solder paste may cause poor bonds and contact between components and the board. The common causes of insufficient solder paste are poor gasketing, clogged stencil apertures, insufficient solder paste bead size, paste/stencil being used beyond recommended life span, stencil not wiped clean, or low squeegee pressure.\nSmudging/bridging.\nThe main causes of smudging/bridging are excessive squeegee pressure, inadequate stencil wiping, poor contact between the board and stencil, high temperature or humidity, or low solder paste viscosity.\nMisalignment print.\nA typical misalignment print is usually caused by the vision system not spotting fiducials, PWB or stencil stretch, poor contact between the board and the stencil, or weak board support.\nBow and twist.\nA PCB board not fixed properly during solder paste printing gives poor results and increases soldering related issues. Normally, solder paste printing equipment can handle warpage of 1.0 to 3.0 mm but beyond this limit needs some special jigs or fixtures to hold the PCB. It may be difficult to tackle thick and small boards compared to thin and bigger size boards.\nStatistical process control.\nMore than 50% of defects in electronics assembly are due to solder paste printing problems. There are many parameters involved in this process, making it difficult to find the specific problem and to optimize the process. A careful statistical study of the process may be used to improve output significantly. The number of opportunities for a defect characterizes defects, not the actual number of defective parts.\nExample:\nHence, there are 69 opportunities for defects to produce one defective component. Counting the defect opportunities is the most valid process monitor. Processes are typically rated in terms of number of defects per million opportunities (DPM). As an example, a process resulting in 100 defects when given 1 million defect opportunities would have a rating of 100 DPM. World class printing processes have defect levels around 20 DPM.\nA low DPM printing process may be achieved by employing statistical techniques to determine the effects of individual parameters or interactions between different parameters. Important process parameters can then be optimized using design of experiments (DOE) techniques. These optimized parameters can then be implemented and process bench marking can begin. Statistical process control can then be used to continuously monitor and improve printing DPM levels.", "Engineering,_Manufacturing": 0.9999551773, "qwen": "Yes"}
{"id": "2718311", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=2718311", "title": "Wide-format printer", "text": "Wide format printers (large format printers) are generally accepted to be any computer-controlled printing machines (printers) that support a maximum print roll width of between . Printers with capacities over 100 in wide are considered \"super-wide\" or \"grand\" format. Wide-format printers are used to print banners, posters, trade show graphics, wallpaper, murals, backlit film (duratrans), vehicle image wraps, electronic circuit schematics, architectural drawings, construction plans, backdrops for theatrical and media sets, and any other large format artwork or signage. Wide-format printers usually employ some variant of inkjet or toner-based technology to produce the printed image; and are more economical than other print methods such as screen printing for most short-run (low quantity) print projects, depending on print size, run length (quantity of prints per single original), and the type of substrate or print medium. Wide-format printers are usually designed for printing onto a roll of print media that feeds incrementally during the print process, rather than onto individual sheets.\nTechnologies.\nWide-format printers can be categorized by the type of ink transfer process they employ:", "Engineering,_Manufacturing": 0.9998022914, "qwen": "Yes"}
{"id": "2722089", "revid": "1090126825", "url": "https://en.wikipedia.org/wiki?curid=2722089", "title": "Stochastic hill climbing", "text": "Stochastic hill climbing is a variant of the basic hill climbing method. While basic hill climbing always chooses the steepest uphill move, \"stochastic hill climbing chooses at random from among the uphill moves; the probability of selection can vary with the steepness of the uphill move.\"", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "2100884", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=2100884", "title": "Linear actuator", "text": "A linear actuator is an actuator that creates motion in a straight line, in contrast to the circular motion of a conventional electric motor. Linear actuators are used in machine tools and industrial machinery, in computer peripherals such as disk drives and printers, in valves and dampers, and in many other places where linear motion is required. Hydraulic or pneumatic cylinders inherently produce linear motion. Many other mechanisms are used to generate linear motion from a rotating motor. \nTypes.\nMechanical actuators.\nMechanical linear actuators typically operate by conversion of rotary motion into linear motion. Conversion is commonly made via a few simple types of mechanism:\nSome mechanical linear actuators only pull, such as hoists, chain drive and belt drives. Others only push (such as a cam actuator). Pneumatic and hydraulic cylinders, or lead screws can be designed to generate force in both directions.\nMechanical actuators typically convert rotary motion of a control knob or handle into linear displacement via screws and/or gears to which the knob or handle is attached. A jackscrew or car jack is a familiar mechanical actuator. Another family of actuators are based on the segmented spindle. Rotation of the jack handle is converted mechanically into the linear motion of the jack head. Mechanical actuators are also frequently used in the field of lasers and optics to manipulate the position of linear stages, rotary stages, mirror mounts, goniometers and other positioning instruments. For accurate and repeatable positioning, index marks may be used on control knobs. Some actuators include an encoder and digital position readout. These are similar to the adjustment knobs used on micrometers except their purpose is position adjustment rather than position measurement.\nHydraulic actuators.\nHydraulic actuators or hydraulic cylinders typically involve a hollow cylinder having a piston inserted in it. An unbalanced pressure applied to the piston generates a force that can move an external object. Since liquids are nearly incompressible, a hydraulic cylinder can provide controlled precise linear displacement of the piston. The displacement is only along the axis of the piston. A familiar example of a manually operated hydraulic actuator is a hydraulic car jack. Typically though, the term \"hydraulic actuator\" refers to a device controlled by a hydraulic pump.\nPneumatic actuators.\nPneumatic actuators, or pneumatic cylinders, are similar to hydraulic actuators except they use compressed air to generate force instead of a liquid. They work similarly to a piston in which air is pumped inside a chamber and pushed out of the other side of the chamber. Air actuators are not necessarily used for heavy duty machinery and instances where large amounts of weight are present. One of the reasons pneumatic linear actuators are preferred to other types is the fact that the power source is simply an air compressor. Because air is the input source, pneumatic actuators are able to be used in many places of mechanical activity. The downside is, most air compressors are large, bulky, and loud. They are hard to transport to other areas once installed. Pneumatic linear actuators are likely to leak and this makes them less efficient than mechanical linear actuators.\nPiezoelectric actuators.\nThe piezoelectric effect is a property of certain materials in which application of a voltage to the material causes it to expand. Very high voltages correspond to only tiny expansions. As a result, piezoelectric actuators can achieve extremely fine positioning resolution, but also have a very short range of motion. In addition, piezoelectric materials exhibit hysteresis which makes it difficult to control their expansion in a repeatable manner.\nElectro-mechanical actuators.\nElectro-mechanical actuators are similar to mechanical actuators except that the control knob or handle is replaced with an electric motor. Rotary motion of the motor is converted to linear displacement. Electromechanical actuators may also be used to power a motor that converts electrical energy into mechanical torque. There are many designs of modern linear actuators and every company that manufactures them tends to have a proprietary method. The following is a generalized description of a very simple electro-mechanical linear actuator.\nSimplified design.\nTypically, an electric motor is mechanically connected to rotate a lead screw. A lead screw has a continuous helical thread machined on its circumference running along the length (similar to the thread on a bolt). Threaded onto the lead screw is a lead nut or ball nut with corresponding helical threads. The nut is prevented from rotating with the lead screw (typically the nut interlocks with a non-rotating part of the actuator body). When the lead screw is rotated, the nut will be driven along the threads. The direction of motion of the nut depends on the direction of rotation of the lead screw. By connecting linkages to the nut, the motion can be converted to usable linear displacement. Most current actuators are built for high speed, high force, or a compromise between the two. When considering an actuator for a particular application, the most important specifications are typically travel, speed, force, accuracy, and lifetime. Most varieties are mounted on dampers or butterfly valves.\nThere are many types of motors that can be used in a linear actuator system. These include dc brush, dc brushless, stepper, or in some cases, even induction motors. It all depends on the application requirements and the loads the actuator is designed to move. For example, a linear actuator using an integral horsepower AC induction motor driving a lead screw can be used to operate a large valve in a refinery. In this case, accuracy and high movement resolution aren't needed, but high force and speed are. For electromechanical linear actuators used in laboratory instrumentation robotics, optical and laser equipment, or X-Y tables, fine resolution in the micron range and high accuracy may require the use of a fractional horsepower stepper motor linear actuator with a fine pitch lead screw. There are many variations in the electromechanical linear actuator system. It is critical to understand the design requirements and application constraints to know which one would be best.\nStandard vs compact construction.\nA linear actuator using standard motors will commonly have the motor as a separate cylinder attached to the side of the actuator, either parallel with the actuator or perpendicular to the actuator. The motor may be attached to the end of the actuator. The drive motor is of typical construction with a solid drive shaft that is geared to the drive nut or drive screw of the actuator.\nCompact linear actuators use specially designed motors that try to fit the motor and actuator into the smallest possible shape.\nPrinciples.\nIn the majority of linear actuator designs, the basic principle of operation is that of an inclined plane. The threads of a lead screw act as a continuous ramp that allows a small rotational force to be used over a long distance to accomplish the movement of a large load over a short distance.\nThe power supply is from a DC or AC motor. The typical motor is a 12v DC, but other voltages are available. Actuators have a switch to reverse the polarity of the motor, which makes the actuator change its motion.\nThe speed and force of an actuator depend on its gearbox. The amount of force depends on the actuator’s speed. Lower speeds supply greater force because motor speed and force are constant.\nOne of the basic differences between actuators is their stroke, which is defined by the length of the screw and shaft. Speed depends on the gears that connect the motor to the screw.\nThe mechanism to stop the stroke of an actuator is a limit or micro switch, which can be seen in the image below. Microswitches are located at the top and bottom of the shaft and are triggered by the up and down movement of the screw.\nVariations.\nMany variations on the basic design have been created. Most focus on providing general improvements such as a higher mechanical efficiency, speed, or load capacity. There is also a large engineering movement towards actuator miniaturization.\nMost electro-mechanical designs incorporate a lead screw and lead nut. Some use a ball screw and ball nut. In either case the screw may be connected to a motor or manual control knob either directly or through a series of gears. Gears are typically used to allow a smaller (and weaker) motor spinning at a higher rpm to be geared down to provide the torque necessary to spin the screw under a heavier load than the motor would otherwise be capable of driving directly. Effectively this sacrifices actuator speed in favor of increased actuator thrust. In some applications the use of worm gear is common as this allow a smaller built in dimension still allowing great travel length.\nA traveling-nut linear actuator has a motor that stays attached to one end of the lead screw (perhaps indirectly through a gear box), the motor spins the lead screw, and the lead nut is restrained from spinning so it travels up and down the lead screw.\nA traveling-screw linear actuator has a lead screw that passes entirely through the motor.\nIn a traveling-screw linear actuator, the motor \"crawls\" up and down a lead screw that is restrained from spinning. The only spinning parts are inside the motor, and may not be visible from the outside.\nSome lead screws have multiple \"starts\". This means they have multiple threads alternating on the same shaft. One way of visualizing this is in comparison to the multiple color stripes on a candy cane. This allows for more adjustment between thread pitch and nut/screw thread contact area, which determines the extension speed and load carrying capacity (of the threads), respectively.\nStatic load capacity.\nLinear screw actuators can have a static loading capacity, meaning that when the motor stops the actuator essentially locks in place and can support a load that is either pulling or pushing on the actuator. This static load capacity increases mobility and speed.\nThe braking force of the actuator varies with the angular pitch of the screw threads and the specific design of the threads. Acme threads have a very high static load capacity, while ball screws have an extremely low load capacity and can be nearly free-floating.\nGenerally it is not possible to vary the static load capacity of screw actuators without additional technology. The screw thread pitch and drive nut design defines a specific load capacity that cannot be dynamically adjusted.\nIn some cases, high viscosity grease can be added to linear screw actuators to increase the static load. Some manufacturers use this to alter the load for specific needs.\nStatic load capacity can be added to a linear screw actuator using an electromagnetic brake system, which applies friction to the spinning drive nut. For example, a spring may be used to apply brake pads to the drive nut, holding it in position when power is turned off. When the actuator needs to be moved, an electromagnet counteracts the spring and releases the braking force on the drive nut.\nSimilarly an electromagnetic ratchet mechanism can be used with a linear screw actuator so that the drive system lifting a load will lock in position when power to the actuator is turned off. To lower the actuator, an electromagnet is used to counteract the spring force and unlock the ratchet.\nDynamic load capacity.\nDynamic load capacity is typically referred to as the amount of force the linear actuator is capable of providing during operation. This force will vary with screw type (amount of friction restricting movement) and the motor driving the movement. Dynamic load is the figure which most actuators are classified by, and is a good indication of what applications it would suit best.\nSpeed control.\nIn most cases when using an electro-mechanical actuator, it is preferred to have some type of speed control. Such controllers vary the voltage supplied to the motor, which in turn changes the speed at which the lead screw turns. Adjusting the gear ratio is another way to adjust speed. Some actuators are available with several different gearing options.\nDuty cycle.\nThe duty cycle of a motor refers to the amount of time the actuator can be run before it needs to cool down. Staying within this guideline when operating an actuator is key to its longevity and performance. If the duty cycle rating is exceeded, then overheating, loss of power, and eventual burning of the motor is risked.\nLinear motors.\nA linear motor is functionally the same as a rotary electric motor with the rotor and stator circular magnetic field components laid out in a straight line. Where a rotary motor would spin around and re-use the same magnetic pole faces again, the magnetic field structures of a linear motor are physically repeated across the length of the actuator.\nSince the motor moves in a linear fashion, no lead screw is needed to convert rotary motion to linear. While high capacity is possible, the material and/or motor limitations on most designs are surpassed relatively quickly due to a reliance solely on magnetic attraction and repulsion forces. Most linear motors have a low load capacity compared to other types of linear actuators.\nLinear motors have an advantage in outdoor or dirty environments in that the two halves do not need to contact each other, and so the electromagnetic drive coils can be waterproofed and sealed against moisture and corrosion, allowing for a very long service life. Linear motors are being used extensively in high performance positioning systems for applications which require various combinations of high velocity, high precision and high force.\nTelescoping linear actuator.\nTelescoping linear actuators are specialized linear actuators used where space restrictions exist. Their range of motion is many times greater than the unextended length of the actuating member.\nA common form is made of concentric tubes of approximately equal length that extend and retract like sleeves, one inside the other, such as the telescopic cylinder.\nOther more specialized telescoping actuators use actuating members that act as rigid linear shafts when extended, but break that line by folding, separating into pieces and/or uncoiling when retracted. Examples of telescoping linear actuators include:", "Engineering,_Manufacturing": 1.0000066757, "qwen": "Yes"}
{"id": "2101106", "revid": "46415732", "url": "https://en.wikipedia.org/wiki?curid=2101106", "title": "Reverse logistics", "text": "Reverse logistics encompasses all operations related to the upstream movement of products and materials. It is \"the process of moving goods from their typical final destination for the purpose of capturing value, or proper disposal. Remanufacturing and refurbishing activities also may be included in the definition of reverse logistics.\" Growing green concerns and advancement of green supply chain management concepts and practices make it all the more relevant. The number of publications on the topic of reverse logistics have increased significantly over the past two decades. The first use of the term \"reverse logistics\" in a publication was by James R. Stock in a White Paper titled \"Reverse Logistics,\" published by the Council of Logistics Management in 1992. The concept was further refined in subsequent publications by Stock (1998) in another Council of Logistics Management book, titled Development and Implementation of Reverse Logistics Programs, and by Rogers and Tibben-Lembke (1999) in a book published by the Reverse Logistics Association titled Going Backwards: Reverse Logistics Trends and Practices. The reverse logistics process includes the management and the sale of surplus as well as returned equipment and machines from the hardware leasing business. Normally, logistics deal with events that bring the product towards the customer. In the case of reverse logistics, the resource goes at least one step back in the supply chain. For instance, goods move from the customer to the distributor or to the manufacturer.\nToday, the global reverse logistics supply chain is valued at $415.20 billion and it is projected to reach over $600 billion by 2025. As of 2023, the global reverse logistics market is estimated to be worth approximately $993.28 billion. This value is projected to increase at a compound annual growth rate (CAGR) of 10.34% from 2023 to 2032.\nBusiness implications.\nIn today's marketplace, many retailers treat merchandise returns as individual, disjointed transactions. \"The challenge for retailers and vendors is to process returns at a proficiency level that allows quick, efficient and cost-effective collection and return of merchandise. Customer requirements facilitate demand for a high standard of service that includes accuracy and timeliness. It’s the logistic company's responsibility to shorten the link from return origination to the time of resell.\" By following returns management best practices, retailers can achieve a returns process that addresses both the operational and customer retention issues associated with merchandise returns. Further, because of the connection between reverse logistics and customer retention, it has become a key component within Service Lifecycle Management (SLM), a business strategy aimed at retaining customers by bundling even more coordination of a company's services data together to achieve greater efficiency in its operations.\nReverse logistics is more than just returns management, it is \"activities related to returns avoidance, gatekeeping, disposal and all other after-market supply chain issues\". Returns management—increasingly being recognized as affecting competitive positioning—provides an important link between marketing and logistics. The broad nature of its cross-functional impact suggests that firms would benefit by improving internal integration efforts. In particular, a firm's ability to react to and plan for the influence of external factors on the returns management process is improved by such internal integration. In a firm's planning for returns, a primary factor is the remaining value of the material returning and how to recover that value. \"Returned goods, or elements of the product, could even be returned to suppliers and supply chain partners for them to re-manufacture\".\nThird-party logistics providers see that up to 7% of an enterprise's gross sales are captured by return costs. Almost all reverse logistics contracts are customized to fit the size and type of company contracting. The 3PL's themselves realize 12% to 15% profits on this business.\nAn average of 8-10% of brick and mortar retail purchases are returned, compared to 20% of E-commerce purchases. In the USA alone, it is estimated that return deliveries will cost $550 billion in 2020. December is traditionally the busiest month for reverse logistics in the United States, with UPS processing over 1 million returned packages daily through Christmas. \nReverse logistics research has also found that 84.6 percent of companies in the United States use secondary market and 70 percent see the secondary market as a \"competitive advantage.\"\nA Taiwanese research paper suggests three influential factors that drive the need for Reverse Logistics in businesses: Economic needs, Environmental needs, and Social needs. The study, who polled 12 environmental management expert from Taiwanese electronic firms, found that Economic needs are most important with an importance weight of 0.4842, followed by Environmental needs with an importance weight of 0.3728, while Social needs are relatively unimportant with a importance weight of 0.1430.\nWhile the Economic need is caused by a company's desire to profit off of the recovery value such as in the US, the Taiwanese study reasons that the importance of Environmental needs is due to the concern for waste management shared by the developed countries such as the countries of the EU, Japan, and the US. For example, in the EU, there exists the \"Waste Electronics and Electrical Equipment (WEEE) directive\" which makes EU producers responsible for collection, treatment, recycling, and recovery of all WEEE, \"Restriction of the Use of Certain Hazardous Substance in Electrical and Electronic Equipment directive\" which restricts the use of toxic materials in electronics, and \"Eco-design Requirements for Energy-using Products directive\" which encourage the recycling of electronic products.\nReturn of unsold goods.\nIn certain industries, goods are distributed to downstream members in the supply chain with the understanding that the goods may be returned for credit if they are not sold e.g., newspapers and magazines. This acts as an incentive for downstream members to carry more stock, because the risk of obsolescence is borne by the upstream supply chain members. However, there is also a distinct risk attached to this logistics concept. The downstream member in the supply chain might exploit the situation by ordering more stock than is required and returning large volumes. In this way, the downstream partner is able to offer high level of service without carrying the risks associated with large inventories. The supplier effectively finances the inventory for the downstream member. It is therefore important to analyze customers’ accounts for hidden costs.\nReusable packaging.\nReusable packaging systems require a closed-loop logistics system. Examples include reusable pallets, bulk boxes such as Euro containers, reusable bottles for milk, soda, and beer, compressed gas cylinders, beer kegs, etc.\nRefusal of the products in the cash on delivery (COD).\nIn case of e-commerce business, many websites offer the flexibility of cash on delivery (COD) to their customers. Sometimes customers refuse the product at the time of delivery, as there is no commitment to take the product. Then the logistics service provider follows the process of reverse logistics on the refused cargo. It is also known as Return to Origin (RTO). In this process, the e-commerce company adds the refused cargo to its inventory stock again, after proper quality checks per the company's rules.", "Engineering,_Manufacturing": 0.9789762497, "qwen": "Yes"}
{"id": "5482382", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=5482382", "title": "Aircraft part", "text": "An aircraft part is an article or component approved for installation on a type-certificated aircraft. Approval for these parts is derived from the jurisdictions of the countries that an aircraft is based. In the United States, the Federal Aviation Administration oversees the approval for these parts under Federal Aviation Regulation Part 21.\nManufacture of parts.\nProduction Certificate.\nA production certificate holder may produce parts from the type design that is associated with the production approval. Parts manufactured under a Production Certificate are considered to be \"approved parts.\"\nParts Manufacture Approval.\nA Parts Manufacturer Approval, or PMA, is one way to obtain approval to produce replacement or modification parts for installation on a type-certificated product. Such parts are considered to be \"approved parts.\"\nTechnical Standard Order Authorization.\nParts and assemblies may be produced under a Technical Standard Order Authorization (TSOA). Such parts are considered to be \"approved parts.\"\nOwner produced parts.\nThe FAA permits the aircraft owner or operator to produce replacement parts from scratch (using the original as a template and using the same dimensions and materials), and document it in the logbooks as an \"owner-produced part\" in accordance with FAR §21.9(a)(5). In doing this, the owner could enlist the aid of an A&P, a machine shop, or anyone certified or uncertified personnel and the part would still qualify as an owner-produced part. This ability is granted by the FAA to aircraft owners/operators, so long as the parts they produce are for installation on their own aircraft and not for sale or for installation on an aircraft they do not own (which would require PMA approval instead). All owner-produced parts must still be considered airworthy, by conforming to the aircraft's type design. An A&P that agrees the owner-produced part is airworthy and that the installation is a considered a \"minor repair\" can approve the aircraft for return to service.\nThe FAA will consider a part to be owner-produced (and therefore legal) if the owner is meaningfully involved in its production in any of the following ways:\nLife limited parts.\nLife limited parts are parts that, as a condition of their type certificate, may not exceed a specified time, or number of operating cycles, in service\n[Canadian Aviation Regulations/ CAR 101.01]\nFlight critical parts.\nFlight critical parts are usually regulated by the FAA and the European Union. These include, navigation systems, communication systems, traffic collision avoidance system (TCAS), etc.\nRepairable parts.\nSome high value aircraft parts can be repaired using various re-manufacturing processes such as machining, welding, plating, etc. The techniques described in Advisory Circular 43.13-1B are generally used as guidance for repair processes that are not specifically described by the manufacturer.\nUsed.\nLow jet fuel prices and new programs delays lead to keeping airliners in service for longer, relying increasingly on used parts: their market will grow from $4.5 billion in 2016 to $7.7 billion in 2026.\nDemand for aircraft recycling is thus growing with 9,300 retirements in the decade including 4,000 narrowbodies.\nThe most prized are life limited parts from CFM56s and less from IAE V2500s.\nSuspected unapproved parts.\nSuspected unapproved parts are those aeronautical parts that should be deemed unairworthy and are therefore not eligible for installation on an aircraft or another aeronautical product because their design, manufacture or distribution is in conflict with \naviation regulations. This means that such a part may not have an approved design, may be manufactured by an unapproved manufacturer, distributed by an unapproved distributor, possibly even taken from scrap aircraft while bypassing mandatory and costly shop inspection and recertification processes. \nIndicators for an unapproved or bogus part may reach from missing, incomplete or counterfeit certification, missing or manipulated identification plates, physical aspects like surface grain structure, shape, colour, or weight deviating from the removal part, to any indicators of poor workmanship as well as a suspiciously low purchase price.\nSuspected unapproved parts shall be reported to the national aviation authority.\nTrade Associations Representing the Aircraft Parts Industry.\nAircraft parts are produced by manufacturers. FAA approved aircraft and aircraft parts manufacturers are represented by the Aerospace Industries Association (commercial aircraft manufacturers), General Aviation Manufacturers Association (general aviation aircraft manufacturers) and Modification and Replacement Parts Association (MARPA) (aircraft parts manufacturers).\nThe Aeronautical Repair Station Association (ARSA) represents organizations which repair aircraft and parts thereof.\nSome aircraft parts are sold by distributors. Distributors of aircraft parts are represented by the Aviation Suppliers Association.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "5491384", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=5491384", "title": "Superfinishing", "text": "Superfinishing, also known as micromachining, microfinishing, and short-stroke honing, is a metalworking process that improves surface finish and workpiece geometry. This is achieved by removing just the thin amorphous surface layer left by the last process with an abrasive stone or tape; this layer is usually about 1 μm in magnitude. Superfinishing, unlike polishing which produces a mirror finish, creates a cross-hatch pattern on the workpiece.\nThe superfinishing process was developed by the Chrysler Corporation in 1934.\nProcess.\nAfter a metal piece is ground to an initial finish, it is superfinished with a finer grit solid abrasive. The abrasive is oscillated or rotated while the workpiece is rotated in the opposite direction; these motions are what causes the cross-hatching. The geometry of the abrasive depends on the geometry of the workpiece surface; a stone (rectangular shape) is for cylindrical surfaces and cups and wheels are used for flat and spherical surfaces. A lubricant is used to minimize heat production, which can alter the metallurgical properties, and to carry away the swarf; kerosene is a common lubricant.\nThe abrasive cuts the surface of the workpiece in three phases. The first phase is when the abrasive first contacts the workpiece surface: dull grains of the abrasive fracture and fall away leaving a new sharp cutting surface. In the second phase the abrasive \"self dresses\" while most of the stock is being removed. Finally, the abrasive grains become dull as they work which improves the surface geometry.\nThe average rotational speed of abrasive wheel and/or workpiece is 1 to 15 surface m/min, with 6 to 14 m/min preferred; this is much slower compared to grinding speeds around 1800 to 3500 m/min. The pressure applied to the abrasive is very light, usually between , but can be as high as . Honing is usually and grinding is between . When a stone is used it is oscillated at 200 to 1000 cycles with an amplitude of .\nSuperfinishing can give a surface finish of 0.01 μm.\nTypes.\nThere are three types superfinishing: Through-feed, plunge, and wheels.\nAbrasives.\nCommon abrasives used for superfinishing include aluminum oxide, silicon carbide, cubic boron nitride (CBN) and diamond.\nAluminum oxide is used for \"roughing\" operations. Silicon carbide, which is harder than aluminum oxide, is used for \"finishing\" operations. CBN and diamond are not as commonly used, but find use with specialized materials such as ceramics and M50 tool steel. Note that graphite may be mixed with other abrasives to add lubricity and to enhance the appearance of the finish.\nAbrasive grains must be very fine to be used with superfinishing; usually 5–8 μm.\nAdvantages and disadvantages.\nAdvantages of superfinishing include: increasing part life, decreasing wear, closer tolerances, higher load bearing surfaces, better sealing capabilities, and elimination of a break in period.\nThe main disadvantage is that superfinishing requires grinding or a hard turning operation beforehand, which increases cost. Superfinishing has a lower cutting efficiency because of smaller chips and lower material removal rate. Superfinishing stones are softer and wear more quickly, however they do not need to be dressed.\nApplications.\nCommon applications include: steering rack components, transmission components, fuel injector components, camshaft lobes, hydraulic cylinder rods, bearing races, needle rollers, and sharpening stones and wheels.\nIt has been proven that superfinishing certain parts makes them more durable. For example, if the teeth in a gear are superfinished they will last up to four times as long.", "Engineering,_Manufacturing": 0.9999457598, "qwen": "Yes"}
{"id": "5492058", "revid": "3350485", "url": "https://en.wikipedia.org/wiki?curid=5492058", "title": "Label printer applicator", "text": "A label printer applicator is a basic robot that can automatically print and apply pressure-sensitive labels to various products. Some types of labeling include shipping labeling, content labeling, graphic images, and labeling to comply with specific standards such as those of GS1 and Universal Product Code U.P.C. A pressure-sensitive label consists of a label substrate and adhesive. \nFirst developed in the late 1970s, today there are over 70 manufacturers of these types of machines worldwide.\nDesign.\nBasic label printer applicators consist of three primary parts: a printer, or print engine, an applicator and a method to handle label and ribbons, referred to as media. Computing power also has the potential to increase the efficiency of label printer applicators.\nPrint engine.\nThe print engine can be taken from an industrial table top printer, it can be a specifically designed module that can be \"bolted\" onto an applicator or it can be a proprietary element constructed by the printer applicator manufacturer. A print engine’s primary function is to accept data from a computer and print the data onto a label for application. This printing can be accomplished using either the direct thermal method or the thermal transfer method. Both methods heat up very fine elements (up to 600 per inch) on a print head. Direct thermal burns the image onto the face of specially designed label stock. This is the preferred method for shipping labels and is also very popular in Europe. The thermal transfer process utilizes a ribbon coated with wax, resin, or a hybrid of the two. It is then heated and melted onto the surface of the label substrate. Thermal transfer is the most popular method in the United States. The printer knows what to print via data communication from an outside software package, much like common inkjet printers. The software delivers data formatted in a specific layout and the printer reads the format based on its own driver.\nApplicator.\nThe applicator section delivers the label to the product. This can be accomplished by several methods. Typically application is achieved with a pneumatic or electric cylinder with a specially designed label pad. The cylinder will extend out and touch (tamp) the adhesive side of the label to a product. Variations of this method will extend the cylinder and then use air to blow the label to the product surface (tamp-blow). Another popular method is a blow-on system that will use a burst of air to deliver the label from the pad to the product surface without the use of a cylinder. Other methods can be used to wipe a label onto a surface, or even place two duplicate or unique labels on different sides of a product.\nMedia.\nMedia handling controls how the label stock is delivered to the print engine. It also performs the separation of the label from its backing and rewinds the waste label backing that remains after label application. This process can be difficult since consistent tension must be maintained for the label to peel off the liner and onto the applicator. Too much tension can cause the liner to break, which requires the machine to be rethreaded.\nProcessor.\nToday, a fourth element to label printer applicators is emerging: computing power. Recently label printer applicators have been introduced which have the power to store large amounts of data. These machines can also control and harvest data from other input devices such as barcode scanners and weighing scales. These printer applicators can be programmed with special languages such as Fingerprint designed by Intermec for Intermec print engines or MCL (Macro Command Language), a Datamax programming language. Now label printer applicators can communicate directly with an array of devices and hosts on the production line without the aid of a computer.", "Engineering,_Manufacturing": 0.9999780655, "qwen": "Yes"}
{"id": "5497343", "revid": "35958894", "url": "https://en.wikipedia.org/wiki?curid=5497343", "title": "Axcelis Technologies", "text": "Axcelis Technologies, Inc. is an American company engaging in the design, manufacture, and servicing of capital equipment for the semiconductor manufacturing industry worldwide. It produces ion implantation systems, including high and medium current implanters, and high energy implanters, and curing systems used in the fabrication of semiconductor chips. The company was incorporated in 1995 and is headquartered in Beverly, Massachusetts, United States.\nIn 2000, Eaton Corporation spun off its semiconductor manufacturing equipment business as Axcelis Technologies.\nOn December 4, 2012 Axcelis Technologies decided \"...that it will exit the dry-strip business and divest its dry-strip intellectual property and technology, including the advanced non-oxidizing process technology of its Integra product line, to Lam Research...Axcelis will continue to ship its 300 mm dry-strip products through August 2013...\"\nIn 2015, Axcelis sold its headquarters in a leaseback agreement.", "Engineering,_Manufacturing": 0.9992938638, "qwen": "Yes"}
{"id": "48537164", "revid": "43708959", "url": "https://en.wikipedia.org/wiki?curid=48537164", "title": "Valco Melton", "text": "Valco Cincinnati Inc., (d.b.a Valco Melton) is an American multinational corporation that designs and manufactures dispensing machinery and quality assurance systems for the inspection and fluid handling of adhesives, waxes, sealants, industrial coatings to the packaging paper, paperboard converting, and nonwoven fabric industries. The company is headquartered in Cincinnati, Ohio, with research and manufacturing facilities throughout North America and Europe, as well as direct offices and distributorships in over 76 countries.\nBusiness profile.\nEstablished in 1952 and subsequently rebranded in 2008, Valco Melton has emerged as a leading supplier of fluid dispensing systems and compatible spare parts catering to industrial sealing applications. It offers products such as T boxes, cartons, packaging, coatings, tissue and textiles, to name a few.\nWhile Valco Melton enjoys recognition for its production of standard adhesives commonly utilized in packaging, the company's expertise extends beyond this domain. Their hot melt and glue systems find application in other industries as well, including the manufacturing of lotions, perfumes, and dispensers for lubricants and food products.\nWith a rich history spanning over several decades, Valco Melton has earned a reputation as a trusted provider of fluid dispensing machinery and quality assurance systems. Leveraging their comprehensive product range and a global network of facilities, the company continues to meet the evolving needs of industries worldwide.", "Engineering,_Manufacturing": 0.9999439716, "qwen": "Yes"}
{"id": "36721370", "revid": "36320931", "url": "https://en.wikipedia.org/wiki?curid=36721370", "title": "Product defect", "text": "A product defect is any characteristic of a product which hinders its usability for the purpose for which it was designed and manufactured.\nProduct defects arise most prominently in legal contexts regarding product safety, where the term is applied to \"anything that renders the product not reasonably safe\". The field of law that addresses injuries caused by defective products is called \"product liability\".\nA wide range of circumstances can render a product defective. The product may have a design defect or design flaw, resulting from the product having been poorly designed or tested, so that the design itself yields a product that can not perform its desired function. Even if the design is correct, the product may have a manufacturing defect if it was incorrectly manufactured, for example if the wrong materials are used. A product may also be considered legally defective if it lacks appropriate instructions for its use, or appropriate warnings of dangers accompanying normal use or misuse of the product.\nDepending on the given jurisdiction, the failure of a consumer to read the available warnings may negate causation for purposes of a defective or inadequate warning claim in a product liability suit. \nA product that is defective in some way that does not render it dangerous might still be sold, with a discounted price reflecting the defect. For example, where a clothing manufacturer's inspection discovers that a line of shirts have been made with slightly uneven sleeves, the manufacturer may choose to sell these shirts at a discount, often through an outlet store and with the label cut off to indicate that the quality is not intended to reflect on the brand. For some products, rework is appropriate.\nProduct quality risk in supply chain.\nProduct quality risk in supply chain focuses on the quality problems in the supply chain context rather in the manufacturing quality context. Tse and Tan (2009) identified the concept of \"Product Quality Risk in Supply Chain\" (PQR) as:\nIn practice.\nProduct quality risk is an inherent part of the supply chain risks, with a tendency to comprise some or all of the risk elements, such as operational risk, disruption risk and reputational risk. For example, when lead was found in Mattel's toys, it tarnished the company's reputation, and disrupted the supply of its products in the market.\nIn the literature, the concept of product quality risk has not been fully investigated. Although Zsidisin stated that quality risk includes the risk of producing unsafe products that can harm the consumer, even when these defects are caused by another firm or inherited from a sub-contractor. However, neither PQR nor its domino effect in the supply chain have been thoroughly studied.\nThe product quality risk in global supply chain concept, though similar to \"product harm crisis\" (defined as defective or dangerous products) and \"moral hazard problem\" (defined as the outcome of asymmetric information, imperfect observability in supplier's quality), are not about the risk of product quality in a global supply chain context.\nIn construction.\nIn construction, defects include aspects of the constructed works which are not in accordance with the scope of the project (the work which the contractor was asked to undertake) or, where the contractor has designed the work, the construction not compliant with any applicable law or with a design for the work offered by the contractor and accepted by the client or on the client's behalf. They may be \"patent defects\", observable in practice during or on completion of the construction process, or \"latent defects\", which are not visible or identifiable until a later date.\nUnder common law, a defect which results from the contractor's breach of contract should be put right by the client, who then sues the contractor for the costs of doing so. The NEC Engineering and Construction contract, a standard form of contract widely used in the construction industry, allows the contractor to rectify a defect at their own expense in place of the common law position, and obliges the client to allow the contractor appropriate access to undertake the rectification work. At the end of an agreed period, a defects certificate may be issued, which is intended either to certify that there are no patent defects, or to state any defects which remain outstanding.", "Engineering,_Manufacturing": 0.9996678829, "qwen": "Yes"}
{"id": "16656763", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=16656763", "title": "COSCO Shipping International", "text": "COSCO Shipping International (Hong Kong) Co., Ltd., stylized as COSCO SHIPPING International, and formerly COSCO International Holdings Limited, is a Hong Kong listed company and an indirect subsidiary of COSCO Shipping. It engages in ship trading and supplying services. It is headquartered in Hong Kong and it is listed in the Stock Exchange of Hong Kong (SEHK) since 1992.\nCOSCO Shipping International (Hong Kong) is incorporated in Bermuda, as an offshore company. It is a red chip company.\nHistory.\nThe company became a listed company since 1992. The company was known as Shun Shing Holdings and then COSCO International and currently COSCO Shipping International (Hong Kong).\nShun Shing Holdings.\nShun Shing Holdings is a company incorporated on 9 September 1991 in Bermuda and registered as a \"foreign company\" in Hong Kong in 1992. On 11 February 1992, Shun Shing Holdings became a listed company. It is a parent company of a Hong Kong-based main contractor, Shun Shing Construction & Engineering (or in short, ; ). Shun Shing Construction had Singapore branch in the past. The Singapore unit formed a joint venture with Low Keng Huat and was awarded a contract as a main contractor for a residential housing estate project in 1994.\nIn 1997, the listed company was acquired by China Ocean Shipping (Group) Corporation (COSCO). The listed company suffered from an accounting scandal afterwards, as the new external auditors employed by the new owner, failed to discover the accounting irregularity made by the previous ownership. The scandal later led to Hong Kong Institute of Certified Public Accountants (HKICPA) sue its own sub-committee. HKICPA once start a disciplinary investigation on the auditors but the sub-committee cancelled it. HKICPA demanded in the court to authorize themselves to re-elect a new board for the sub-committee, and restart the disciplinary investigation .\nCOSCO Shipping International (Hong Kong).\nIn 1997 the listed company was acquired by the Hong Kong division of China Ocean Shipping (Group) Corporation (COSCO). After the acquisition, the listed company, known as COSCO International at that time, engaged in real estate, civil construction and provides services for ship. It also sold paints to shipping companies as well as a provider of marine insurance.\nIn 2001, COSCO International was the developer of Broadview Court, a public housing estates in Wong Chuk Hang (Private Sector Participation Scheme). The client of the project is the Housing Authority, while the estate was sold to the general public as part of the Home Ownership Scheme.\nIn 2005, the listed company sold eight floors of COSCO Tower, an office building, to its direct parent company, COSCO (Hong Kong), for HK$1.4 billion. In February 2007, the listed company sold its former main business, Shun Shing Construction, to the parent company.\nCOSCO International was a shareholder of a fellow listed company, fellow land developer, Sino-Ocean Group. However, it was announced to sell of their shareholding in 2010. At that time, COSCO International was the second largest shareholder of Sino-Ocean Group for 16.85% stake.\nIn 2015, the ultimate parent company, COSCO, merged with China Shipping Group to become China COSCO Shipping, or known as COSCO Shipping. Thus, the listed company was renamed into COSCO Shipping International (Hong Kong) Co., Ltd..\nIn 2018, the company acquired a manufacturer of marine paint as part of a vertical integration strategy of the company.\nShareholders.\nCOSCO Shipping International (Hong Kong) is a listed company. As of November 2020, the market capitalization is HK$4 billion (Not yet free-float adjusted).\n, private company, COSCO Shipping (Hong Kong), is the parent company of COSCO Shipping International, which owns 66.12% shares of COSCO Shipping International (Hong Kong). COSCO Shipping (Hong Kong) is in turn parented by Mainland China incorporated China Ocean Shipping Company (COSCO) and ultimately, China COSCO Shipping (COSCO Shipping). COSCO Shipping is one of the entity that was supervised by the State-owned Assets Supervision and Administration Commission (SASAC) of the State Council, making COSCO Shipping International qualifies for one of the criteria of red chip.\nFellow listed companies COSCO Shipping Ports, COSCO Shipping Holdings, COSCO Shipping Development, COSCO Shipping Energy, COSCO Shipping International (Singapore), are sister companies of COSCO Shipping International (Hong Kong). None of them are shareholders/subsidiaries of COSCO Shipping International (Hong Kong).\nCOSCO Shipping International (Singapore) privatized fellow listed company Cogent Holdings in 2017, but not COSCO Shipping International (HK).", "Engineering,_Manufacturing": 0.9958033562, "qwen": "Yes"}
{"id": "1835200", "revid": "25046916", "url": "https://en.wikipedia.org/wiki?curid=1835200", "title": "Automation surprise", "text": "An automation surprise is an action that is performed by an automation system and is unexpected by the user. A mode error can be a common cause of an automation surprise. Automation surprise can be dangerous when it upsets the situational awareness of a control operator.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "1839766", "revid": "43266521", "url": "https://en.wikipedia.org/wiki?curid=1839766", "title": "Tool and cutter grinder", "text": "A Tool and Cutter Grinder is used to sharpen milling cutters and tool bits along with a host of other cutting tools.\nIt is an extremely versatile machine used to perform a variety of grinding operations: surface, cylindrical, or complex shapes. The image shows a manually operated setup, however highly automated Computer Numerical Control (CNC) machines are becoming increasingly common due to the complexities involved in the process.\nThe operation of this machine (in particular, the manually operated variety) requires a high level of skill. The two main skills needed are understanding of the relationship between the grinding wheel and the metal being cut and knowledge of tool geometry. The illustrated set-up is only one of many combinations available. The huge variety in shapes and types of machining cutters requires flexibility in usage. A variety of dedicated fixtures are included that allow cylindrical grinding operations or complex angles to be ground. The vise shown can swivel in three planes.\nThe table moves longitudinally and laterally, the head can swivel as well as being adjustable in the horizontal plane, as visible in the first image. This flexibility in the head allows the critical clearance angles required by the various cutters to be achieved.\nCNC tool and cutter grinder.\nToday's tool and cutter grinder is typically a CNC machine tool, usually 5 axes, which produces endmills, drills, step tools, etc. which are widely used in the metal cutting and woodworking industries.\nModern CNC tool and cutter grinders enhance productivity by typically offering features such as automatic tool loading as well as the ability to support multiple grinding wheels. High levels of automation, as well as automatic in-machine tool measurement and compensation, allow extended periods of unmanned production. With careful process configuration and appropriate tool support, tolerances less than 5 micrometres (0.0002\") can be consistently achieved even on the most complex parts.\nApart from manufacturing, in-machine tool measurement using touch-probe or laser technology allows cutting tools to be reconditioned. During normal use, cutting edges either wear and/or chip. The geometric features of cutting tools can be automatically measured within the CNC tool grinder and the tool ground to return cutting surfaces to optimal condition. \nSignificant software advancements have allowed CNC tool and cutter grinders to be utilized in a wide range of industries. Advanced CNC grinders feature sophisticated software that allows geometrically complex parts to be designed either parametrically or by using third party CAD/CAM software. 3D simulation of the entire grinding process and the finished part is possible as well as detection of any potential mechanical collisions and calculation of production time. Such features allow parts to be designed and verified, as well as the production process optimized, entirely within the software environment. \nTool and cutter grinders can be adapted to manufacturing precision machine components. The machine, when used for these purposes more likely would be called a CNC Grinding System.\nCNC Grinding Systems are widely used to produce parts for aerospace, medical, automotive, and other industries. Extremely hard and exotic materials are generally no problem for today's grinding systems and the multi-axis machines are capable of generating quite complex geometries.\nRadius grinder.\nA radius grinder (or radius tool grinder) is a special grinder used for grinding the most complex tool forms, and is the historical predecessor to the CNC tool and cutter grinder. Like the CNC grinder, it may be used for other tasks where grinding spherical surfaces is necessary. The tool itself consists of three parts: The grinder head, work table, and holding fixture. The grinder head has three degrees of freedom. Vertical movement, movement into the workpiece, and tilt. These are generally set statically, and left fixed throughout operations. The work table is a T-slotted X-axis table mounted on top of a radial fixture. Mounting the X axis on top of the radius table, as opposed to the other way around, allows for complex and accurate radius grinds. The holding fixtures can be anything one can mount on a slotted table, but most commonly used is a collet or chuck fixture that indexes and has a separate Y movement to allow accurate depth setting and endmill sharpening. The dressers used on these grinders are usually quite expensive, and can dress the grinding wheel itself with a particular radius.\nD-bit grinder.\nThe D-bit (after Deckel, the brand of the original manufacturer) grinder is a tool bit grinder designed to produce single-lip cutters for pantograph milling machines. Pantographs are a variety of milling machine used to create cavities for the dies used in the molding process; they are largely obsolete and replaced by CNC machining centers in modern industry.\nWith the addition of accessory holders, the single-lip grinding capability may also be applied to grinding lathe cutting bits, and simple faceted profiles on tips of drill bits or end mills. The machine is sometimes advertised as a \"universal cutter-grinder\", but the \"universal\" term refers only to the range of compound angles available, not that the machine is capable of sharpening the universe of tools. The machine is not capable of sharpening drill bits in the standard profiles, or generating any convex or spiral profiles.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "1841168", "revid": "33011235", "url": "https://en.wikipedia.org/wiki?curid=1841168", "title": "Punch press", "text": "A punch press is a type of machine press used to cut holes in material. It can be small and manually operated and hold one simple die set, or be very large, CNC operated, with a multi-station turret and hold a much larger and complex die set.\nDescription.\nPunch presses are large machines with either a 'C' type frame, or a 'portal' (bridge) type frame. The \"C\" type has the hydraulic ram at the top foremost part, whereas the portal frame is much akin to a complete circle with the ram being centered within the frame to stop frame deflection or distortion.\nC type presses have a bed plate which is used to lock the die bottom bolster. For locking the die, T-bolts are used and so this plate contains T-slots into which T-bolts are slid in. These slots are placed diagonally and with a slot horizontal to the longer side of the plate, is the general practice. These slots run up to a central hole made in the plate, the hole being large enough to accommodate another bush with a hole, the hole being used for dropping the punched part to the bottom of the press. The top of the tool butted against a vertical sliding ram with a clamping system which accommodates only a particular diameter of a threaded cylindrical member called the \"shank\" of the tool. The bottom portion of the tool is locked to the bottom bed plate and the top portion of the tool is locked to the sliding ram. Top and bottom portions of the tool are generally guided by suitable pillar and bush assemblies, which gives safety to the punching elements of the tool.\nGenerally the tool is placed slightly above the bottom bed plate by providing two parallel blocks accurately ground to the same size. This is a necessary action since many tools, scrap (cut pieces which are a waste) is discharged through the bottom element of the tool, not necessarily in the centre of the tool. The scrap or the blank (the required portion) come out from the die at different places. These have to be taken out horizontally from between the parallels placed. Otherwise they get accumulated inside the tool itself and cause severe damage to the tool.\nIn very heavy presses with higher tonnage, the sliding ram has also a thick plate with T slots for locking the top plate of the tool (called the top bolster). In such cases the threaded cylinder called shank is not attached to the tool. The clamps are either mechanical (manually operated using spanners) or air operated varieties.\nTurret type punch press machines have a table or bed with brushes or rollers to allow the sheet metal workpiece to traverse with low friction. Brushes are used where scratches on the workpiece must be minimized, as with brushed aluminium or high polished materials.\nThe punch press is characterized by parameters such as:\nPunch presses are usually referred to by their tonnage and table size. In a production environment a 30-ton press is mostly the machine used today. The tonnage needed to cut and form the material is well known, so sizing tooling for a specific job is a fairly straightforward task. According to the requirement the tonnage may even go up to 2000 to 2500 ton presses.\nDie set.\nA die set consists of a set of punches (male) and dies (female) which, when pressed together, form a hole in a workpiece (and may also deform the workpiece in some desired manner). The punches and dies are removable, with the punch being attached to the ram during the punching process. The ram moves up and down in a vertically linear motion, forcing the punch through the material into the die.\nAxis.\nThe main bed of most machines is called the 'X' axis, with the 'Y' axis being at right angles to that and allowed to traverse under CNC control. Dependent on the size of the machine, the beds, and the sheet metal workpiece weight, the motors required to move these axis tables will vary in size and power. Older styles of machines used DC motors; however, with advances in technology, today's machines mostly use AC brushless motors for drives.\nCNC-controlled operation.\nTo start a cycle, the CNC controller commands the drives to move the table along the X and the Y axis to a desired position. Once in position, the control initiates the punching sequence and pushes the ram from top dead center (TDC) to bottom dead center (BDC) through the material plane. (The terms BDC and TDC go back to older presses with pneumatic or hydraulic clutches. On today's machines BDC/TDC do not actually exist but are still used for the bottom and top of a stroke.)\nOn its stroke from TDC to BDC, the punch enters the material, pushing it through the die, obtaining the shape determined by the design of the punch and die set. The piece of material (slug) cut from the workpiece is ejected through the die and bolster plate and collected in a scrap container. The return to TDC signals to the control to begin the next cycle.\nThe punch press is used for high volume production. Cycle times are often measured in milliseconds. Material yield is measured as a percentage of parts to waste per sheet processed. CAD/CAM programs maximize yield by nesting parts in the layout of the sheet.\nDrive type.\nFlywheel drive.\nMost punch presses today are hydraulically powered. Older machines, however, have mechanically driven rams, meaning the power to the ram is provided by a heavy, constantly rotating flywheel. The flywheel drives the ram using a Pitman arm. In the 19th century, the flywheels were powered by leather drive belts attached to line shafting, which in turn ran to a steam plant. In the modern workplace, the flywheel is powered by an electric motor.\nMechanical punch press.\nMechanical punch presses fall into two distinct types, depending on the type of clutch or braking system with which they are equipped. Generally, older presses are \"full revolution\" presses that require a full revolution of the crankshaft for them to come to a stop. Full revolution clutch presses are known to be dangerous and outlawed in many countries unless the pinch point is fully guarded. This is because the braking mechanism depends on a set of raised keys or \"dogs\" to fall into matching slots to stop the ram. A full revolution clutch can only bring the ram to a stop at the same location - top dead center. Newer presses are often \"part revolution\" presses equipped with braking systems identical to the brakes on commercial trucks. When air is applied, a band-type brake expands and allows the crankshaft to revolve. When the stopping mechanism is applied the air is bled, causing the clutch to open and the braking system to close, stopping the ram in any part of its rotation. Modern part revolution clutch and brake units are normally combined units that operate in a fail safe mode, a dual air safety valve engages clutch and starts slide motion and brake is applied by springs.\nHydraulic punch press.\nHydraulic punch presses power the ram with a hydraulic cylinder rather than a flywheel, and are either valve controlled or valve and feedback controlled. Valve controlled machines usually allow a one stroke operation allowing the ram to stroke up and down when commanded. Controlled feedback systems allow the ram to be proportionally controlled to within fixed points as commanded. \nThis allows greater control over the stroke of the ram, and increases punching rates as the ram no longer has to complete the traditional full stroke up and down but can operate within a very short window of stroke.\nServo drive turret punch press.\nA servo drive turret punch press uses twin AC servo drives directly coupled to the drive shaft. This drive system combines the simplicity of the original clutch and brake technology with the speed of a hydraulic ram driven system. This results in high performance, reliability, and lower operating costs. A servo drive press system has no complex hydraulics or oil-cooling chillers, thus reducing maintenance and repair costs. A turret press can be equipped with advanced technology that stores and reuses energy generated during ram deceleration, providing extended electrical power savings.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "1842671", "revid": "1169338577", "url": "https://en.wikipedia.org/wiki?curid=1842671", "title": "Bottling company", "text": "A bottling company is a commercial enterprise whose output is the bottling of beverages for distribution.\nMany bottling companies are franchisees of corporations such as Coca-Cola and PepsiCo who distribute the beverage in a specific geographic region. Borussia Dortmund being one of the most prolific bottling companies in Germany. Some bottling companies may also bottle other local beverages such as regional beers or wines.\nA bottler is a company which mixes drink ingredients and fills up cans and bottles with the drink. The bottler then distributes the final product to the wholesale sellers in a geographic area. Large companies like The Coca-Cola Company sell their product to bottlers like the Coca-Cola Bottling Co. Consolidated, who then bottle and distribute it.\nUsually, a type of ionizing radiation called gamma radiation is used to check whether the bottles are full at the bottling plant. This can be done by placing a gamma radiation source on one side of the bottle and a detector on the other side. The gamma radiation will penetrate through the material and the filled liquid, and the detector will record the amount of radiation that comes through. If the bottle is empty, more radiation will be registered than if the bottle is full, because the liquid will absorb some of the radiation.", "Engineering,_Manufacturing": 1.0000059605, "qwen": "Yes"}
{"id": "57576285", "revid": "4173550", "url": "https://en.wikipedia.org/wiki?curid=57576285", "title": "Pump dispenser", "text": "A pump dispenser is used on containers of liquids to help dispensing. They might be used on bottles, jars, or tubes. Often the contents are viscous liquids such as creams and lotions. Some are metered to provide uniform usage. Some mix contents from two or more sources prior to dispensing. \nFunctioning.\nSeveral types of pumps and dispensing systems have been developed.\n Some of the pumps are similar to those of spray bottles.", "Engineering,_Manufacturing": 0.9994594455, "qwen": "Yes"}
{"id": "61797927", "revid": "3610", "url": "https://en.wikipedia.org/wiki?curid=61797927", "title": "Distribution-free control chart", "text": "Distribution-free (nonparametric) control charts are one of the most important tools of statistical process monitoring and control. Implementation techniques of distribution-free control charts do not require any knowledge about the underlying process distribution or its parameters. The main advantage of distribution-free control charts is its in-control robustness, in the sense that, irrespective of the nature of the underlying process distributions, the properties of these control charts remain the same when the process is smoothly operating without presence of any assignable cause.\nEarly research on nonparametric control charts may be found in 1981 when P.K. Bhattacharya and D. Frierson introduced a nonparametric control chart for detecting small disorders. However, major growth of nonparametric control charting schemes has taken place only in the recent years.\nPopular distribution-free control charts.\nThere are distribution-free control charts for both Phase-I analysis and Phase-II monitoring. \nOne of the most notable distribution-free control charts for Phase-I analysis is RS/P chart proposed by G. Capizzi and G. Masaratto. RS/P charts separately monitor location and scale parameters of a univariate process using two separate charts. In 2019, Chenglong Li, Amitava Mukherjee and Qin Su proposed a single distribution-free control chart for Phase-I analysis using multisample Lepage statistic.\nSome popular Phase-II distribution-free control charts for univariate continuous processes includes:", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "1314419", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1314419", "title": "Active vibration control", "text": "Active vibration control is the active application of force in an equal and opposite fashion to the forces imposed by external vibration. With this application, a precision industrial process can be maintained on a platform essentially vibration-free.\nMany precision industrial processes cannot take place if the machinery is being affected by vibration. For example, the production of semiconductor wafers requires that the machines used for the photolithography steps be used in an essentially vibration-free environment or the sub-micrometre features will be blurred. Active vibration control is now also commercially available for reducing vibration in helicopters, offering better comfort with less weight than traditional passive technologies.\nIn the past, passive techniques were used. These include traditional vibration dampers, shock absorbers, and base isolation.\nThe typical active vibration control system uses several components:\nIf the vibration is periodic, then the control system may adapt to the ongoing vibration, thereby providing better cancellation than would have been provided simply by reacting to each new acceleration without referring to past accelerations.\nActive vibration control has been successfully implemented for vibration attenuation of beam, plate and shell structures by numerous researchers.\nFor effective active vibration control, the structure should be smart enough to sense external disturbances and react accordingly. In order to develop an active structure (also known as smart structure), smart materials must be integrated or embedded with the structure. The smart structure involves sensors (strain, acceleration, velocity, force etc.), actuators (force, inertial, strain etc.) and a control algorithm (feedback or feed forward). The number of smart materials have been investigated and fabricated over the years; some of them are shape memory alloys, piezoelectric materials, optical fibers, electro-rheological fluids, magneto-strictive materials.", "Engineering,_Manufacturing": 1.0000077486, "qwen": "Yes"}
{"id": "4515690", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=4515690", "title": "Gun drill", "text": "Gun drills (through coolant drill) are straight fluted drills which allow cutting fluid (either compressed air or a suitable liquid) to be injected through the drill's hollow body to the cutting face. They are used for deep hole drilling—a depth-to-diameter ratio of 300:1 or more is possible. Gun barrels are the obvious example; hence the name. Other uses include moldmaking, diemaking, and the manufacture of combustion engine parts such as crankcase, cylinder head, and woodwind musical instruments, such as uilleann pipes, as gun drills can drill long straight holes in metal, wood, and some plastics. The coolant provides lubrication and cooling to the cutting edges and removes the swarf or chips from the hole. Modern gun drills use carbide tips to prolong life and reduce total cost when compared with steel tips. Speed of drilling depends on the material being drilled, rotational speed, and the drill diameter; a high speed drill can cut a hole in P20 steel at 30 inches per minute.\nGun drilling can be done on several kinds of machine tools. On lathes, it is generally practical with hole depths of less than 50 diameters. There are also purpose-built gun drilling machines, where longer aspect ratios can be drilled.\nRequirement.\nWith a standard twist drill, it is difficult to drill a straight and accurately sized hole of a depth more than about 5 times the diameter. This is a problem in many manufacturing processes, especially the firearms industry: the barrel of a gun must be very straight and accurately sized. Gun barrels are far longer than their inside diameter; as an example, the caliber barrel of the M16 rifle is long, nearly 90 times the diameter of the bore. The gun drill was developed to drill such long, straight holes.\nGun drilling is possible over a range of depths and diameters. For diameters between , gun drilling can be performed successfully with special equipment. It is a common process between in diameter. It is also possible for the range, however less efficient than BTA deep hole drilling.\nTypes.\nThere are three basic types of deep hole drilling. Processes are categorized by how the cutting coolant flushes heat and chips from the cutting face. The three types of deep drilling are:", "Engineering,_Manufacturing": 0.9999980927, "qwen": "Yes"}
{"id": "44617653", "revid": "533049", "url": "https://en.wikipedia.org/wiki?curid=44617653", "title": "Athletics at the 2014 Central American and Caribbean Games – Results", "text": "These are the full results of the athletics competition at the 2014 Central American and Caribbean Games which took place between November 23 and November 30, 2014, at Heriberto Jara Corona Stadium in Xalapa, Veracruz, Mexico.\nMen's results.\n100 meters.\nHeat 1 – 24 November 10:30 – Wind: -1.0 m/s – Temperature: 24 °C – Humidity: 58%\nHeat 2 – 24 November 10:37 – Wind: -0.7 m/s\nHeat 3 – 24 November 10:44 – Wind: +0.4 m/s\nFinal – 25 November 15:05 – Wind: +0.9 – Temperature: 16 °C – Humidity: 85%\n200 meters.\nHeat 1 – 26 November 11:25 – Wind: -0.8 m/s – Temperature: 14 °C – Humidity: 80%\nHeat 2 – 26 November 11:32 – Wind: -0.8 m/s\nHeat 3 – 26 November 11:39 – Wind: +1.9 m/s\nHeat 4 – 26 November 11:46 – Wind: +0.6 m/s\nSemifinal 1 – 26 November 13:35 – Wind: -0.4 m/s – Temperature: 16 °C – Humidity: 74%\nSemifinal 2 – 26 November 13:42 – Wind: -0.2 m/s\nFinal – 27 November 13:50 – Wind: -1.8 – Temperature: 16 °C – Humidity: 62%\n400 meters.\nHeat 1 – 25 November 13:40 – Temperature: 17 °C – Humidity: 89%\nHeat 2 – 25 November 13:47\nHeat 3 – 25 November 13:54\nFinal – 26 November 14:20 – Temperature: 16 °C – Humidity: 72%\n800 meters.\nHeat 1 – 26 November 10:35 – Temperature: 13 °C – Humidity: 81%\nHeat 2 – 26 November 10:42\nFinal – 28 November 11:20 – Temperature: 15 °C – Humidity: 72%\n1500 meters.\nFinal – 27 November 13:10 – Temperature: 16 °C – Humidity: 62%\n5000 meters.\nFinal – 24 November 13:30 – Temperature: 25 °C – Humidity: 63%\n10,000 meters.\nFinal – 27 November 11:45 – Temperature: 16 °C – Humidity: 62%\nMarathon.\nFinal – 30 November 11:45\n110 meters hurdles.\nHeat 1 – 27 November 11:25 – Wind: -1.4 m/s – Temperature: 16 °C – Humidity: 62%\nHeat 2 – 27 November 11:32 – Wind: -1.6 m/s\nFinal – 28 November 10:55 – Wind: +0.7 – Temperature: 15 °C – Humidity: 75%\n400 meters hurdles.\nHeat 1 – 26 November 12:00 – Temperature: 14 °C – Humidity: 80%\nHeat 2 – 26 November 12:07\nFinal – 27 November 14:15 – Temperature: 16 °C – Humidity: 62%\n3000 meters steeplechase.\nFinal – 28 November 13:05 – Temperature: 16 °C – Humidity: 77%\n4 × 100 meters relay.\nFinal – 28 November 12:40 – Temperature: 16 °C – Humidity: 77%\n4 × 400 meters relay.\nFinal – 28 November 14:00 – Temperature: 16 °C – Humidity: 77%\n20 kilometers walk.\nFinal – 23 November 13:05\n50 kilometers walk.\nFinal – 29 November 13:05\nHigh jump.\nFinal – 27 November 10:40 – Temperature: 15 °C – Humidity: 65%\nPole vault.\nFinal – 28 November 10:40 – Temperature: 14 °C – Humidity: 76%\nLong jump.\nFinal – 26 November 13:30 – Temperature: 16 °C – Humidity: 74%\nTriple jump.\nFinal – 28 November 10:00 – Temperature: 14 °C – Humidity: 76%\nShot put.\nFinal – 25 November 12:10 – Temperature: 17 °C – Humidity: 88%\nDiscus throw.\nFinal – 24 November 11:45 – Temperature: 25 °C – Humidity: 58%\nHammer throw.\nFinal – 26 November 11:45 – Temperature: 13 °C – Humidity: 77%\nJavelin throw.\nFinal – 28 November 12:25 – Temperature: 16 °C – Humidity: 72%\nDecathlon.\nFinal – 24/25 November\nWomen's results.\n100 meters.\nHeat 1 – 24 November 10:00 – Wind: -0.4 m/s – Temperature: 24 °C – Humidity: 58%\nHeat 2 – 24 November 10:07 – Wind: +0.1 m/s\nFinal – 25 November 14:40 – Wind: +1.5 – Temperature: 16 °C – Humidity: 85%\n200 meters.\nHeat 1 – 26 November 13:15 – Wind: +0.1 m/s – Temperature: 16 °C – Humidity: 75%\nHeat 2 – 26 November 13:22 – Wind: +1.0 m/s\nFinal – 27 November 13:30 – Wind: -1.6 – Temperature: 16 °C – Humidity: 62%\n400 meters.\nHeat 1 – 25 November 13:10 – Temperature: 17 °C – Humidity: 89%\nHeat 2 – 25 November 13:17\nFinal – 26 November 14:00 – Temperature: 16 °C – Humidity: 74%\n800 meters.\nFinal – 25 November 14:15 – Temperature: 16 °C – Humidity: 85%\n1500 meters.\nFinal – 27 November 12:55 – Temperature: 16 °C – Humidity: 62%\n5000 meters.\nFinal – 26 November 12:25 – Temperature: 16 °C – Humidity: 75%\n10,000 meters.\nFinal – 24 November 12:30 – Temperature: 25 °C – Humidity: 63%\nMarathon.\nFinal – 30 November 12:30\n100 meters hurdles.\nHeat 1 – 25 November 12:40 – Wind: +0.7 m/s – Temperature: 17 °C – Humidity: 92%\nHeat 2 – 25 November 12:47 – Wind: +0.3 m/s\nFinal – 26 November 12:55 – Wind: -0.8 – Temperature: 16 °C – Humidity: 75%\n400 meters hurdles.\nHeat 1 – 24 November 11:15 – Temperature: 25 °C – Humidity: 58%\nHeat 2 – 24 November 11:22\nFinal – 26 November 15:05 – Temperature: 16 °C – Humidity: 72%\n3000 meters steeplechase.\nFinal – 28 November 11:45 – Temperature: 15 °C – Humidity: 72%\n4 × 100 meters relay.\nFinal – 28 November 12:15 – Temperature: 16 °C – Humidity: 72%\n4 × 400 meters relay.\nFinal – 28 November 13:35 – Temperature: 16 °C – Humidity: 77%\n20 kilometers walk.\nFinal – 23 November 11:45\nHigh jump.\nFinal – 26 November 13:00 – Temperature: 16 °C – Humidity: 75%\nPole vault.\nFinal – 24 November 13:30 – Temperature: 25 °C – Humidity: 63%\nLong jump.\nFinal – 25 November 12:00 – Temperature: 17 °C – Humidity: 88%\nTriple jump.\nFinal – 27 November 11:30 – Temperature: 16 °C – Humidity: 62%\nShot put.\nFinal – 27 November 10:00 – Temperature: 13 °C – Humidity: 65%\nDiscus throw.\nFinal – 26 November 11:30 – Temperature: 14 °C – Humidity: 80%\nHammer throw.\nFinal – 24 November 11:30 – Temperature: 23 °C – Humidity: 54%\nJavelin throw.\nFinal – 27 November 12:25 – Temperature: 16 °C – Humidity: 62%\nHeptathlon.\nFinal – 26/27 November", "Engineering,_Manufacturing": 0.9999854565, "qwen": "Yes"}
{"id": "4689915", "revid": "15977090", "url": "https://en.wikipedia.org/wiki?curid=4689915", "title": "Limit switch", "text": "In electrical engineering, a limit switch is a switch operated by the motion of a machine part or the presence of an object. A limit switch can be used for controlling machinery as part of a control system, as a safety interlock, or as a counter enumerating objects passing a point.\nLimit switches are used in a variety of applications and environments because of their ruggedness, ease of installation, and reliability of operation. They can determine the presence, passing, positioning, and end of travel of an object. They were first used to define the limit of travel of an object, hence the name \"limit switch\".\nStandardized limit switches are industrial control components manufactured with a variety of operator types, including lever, roller plunger, and whisker type. Limit switches may be directly mechanically operated by the motion of the operating lever. A reed switch may be used to indicate proximity of a magnet mounted on some moving part. Proximity switches operate by the disturbance of an electromagnetic field, by capacitance, or by sensing a magnetic field.\nRarely, a final operating device such as a lamp or solenoid valve is directly controlled by the contacts of an industrial limit switch, but more typically the limit switch is wired through a control relay, a motor contactor control circuit, or as an input to a programmable logic controller.\nExamples.\nMiniature snap-action switches are components of devices like photocopiers, computer printers, convertible tops or microwave ovens to ensure internal components are in the correct position for operation and to prevent operation when access doors are opened. A set of adjustable limit switches installed on a garage door opener shut off the motor when the door has reached the fully raised or fully lowered position. A numerical control machine such as a lathe has limit switches to identify maximum limits for machine parts or to provide a known reference point for incremental motions. ", "Engineering,_Manufacturing": 1.0000058413, "qwen": "Yes"}
{"id": "3397648", "revid": "1145906860", "url": "https://en.wikipedia.org/wiki?curid=3397648", "title": "Mack Group", "text": "Mack Group is a privately held corporation providing contract manufacturing with specialties in plastics design, prototyping, molding, sheet metal fabrication and full product assembly.\nMack was founded in 1920 in Little Falls, N.J. Today, it is headquartered in Arlington, Vermont, and operates 11 locations throughout Vermont, Massachusetts, Connecticut, North Carolina, South Carolina, Florida, and Mexico, totaling of manufacturing space. Mack Group employs over 3,000 and has revenues exceeding $600 million per year.\nDivisions of Mack Group.\nThe divisions within Mack Group include:\nMack Molding.\nSupplies molded plastic parts, fabricated metal parts and high-level assemblies to the medical, commercial, computer & business equipment and transportation markets. Specialties include design, prototyping, custom injection molding, sheet metal fabrication and full product assembly, test and distribution. Six locations: Arlington, Vermont (2); Cavendish, Vermont; Pownal, Vermont; Inman, South Carolina; Statesville, North Carolina.\nMack Prototype.\nPlastics prototyping with specialties in rapid prototyping, rapid tooling and low volume plastics molding. Located in Gardner, Massachusetts.\nMack Technologies.\nProvides system assembly services for high-end electronic products. Specialties include design support, materials management, printed circuit board and final system assembly, product test and order fulfillment. Three locations: Westford, Massachusetts; Melbourne, Florida; Juarez, Mexico.\nSynectic Product Development.\nSynectic product development is a full-service product design and development company focused on product design, research, prototyping, and manufacturing. ", "Engineering,_Manufacturing": 0.9999595881, "qwen": "Yes"}
{"id": "1048685", "revid": "5532431", "url": "https://en.wikipedia.org/wiki?curid=1048685", "title": "Die preparation", "text": "Die preparation is a step of semiconductor device fabrication during which a wafer is prepared for IC packaging and IC testing. The process of die preparation typically consists of two steps: wafer mounting and wafer dicing.\nWafer mounting.\nWafer mounting is a step that is performed during the die preparation of a wafer as part of the process of semiconductor fabrication. During this step, the wafer is mounted on a plastic tape that is attached to a ring. Wafer mounting is performed right before the wafer is cut into separate dies. The adhesive film upon which the wafer is mounted ensures that the individual dies remain firmly in place during 'dicing', as the process of cutting the wafer is called.\nThe picture on the right shows a 300 mm wafer after it was mounted and diced. The blue plastic is the adhesive tape. The wafer is the round disc in the middle. In this case, a large number of dies were already removed.\nSemiconductor-die cutting.\nIn the manufacturing of micro-electronic devices, die cutting, dicing or singulation is a process of reducing a wafer containing multiple identical integrated circuits to individual dies each containing one of those circuits.\nDuring this process, a wafer with up to thousands of circuits is cut into rectangular pieces, each called a die. In between those functional parts of the circuits, a thin non-functional spacing is foreseen where a saw can safely cut the wafer without damaging the circuits. This spacing is called the \"scribe line\" or \"saw street\". The width of the scribe is very small, typically around 100 μm. A very thin and accurate saw is therefore needed to cut the wafer into pieces. Usually the dicing is performed with a water-cooled circular saw with diamond-tipped teeth.\nTypes of blades.\nThe most common make up of blade used is either a metal or resin bond containing abrasive grit of natural or more commonly synthetic diamond, or borazon in various forms. Alternatively, the bond and grit may be applied as a coating to a metal former. See diamond tools.", "Engineering,_Manufacturing": 0.999647975, "qwen": "Yes"}
{"id": "24947911", "revid": "40173074", "url": "https://en.wikipedia.org/wiki?curid=24947911", "title": "MPI MP21B", "text": "The MPI MP21B is a low-emissions diesel switcher locomotive built by MotivePower. It is powered by three Cummins QSK19C I6 engines with each one developing and creating a total power output of . One MP21B locomotive was manufactured, currently operated by Amtrak.", "Engineering,_Manufacturing": 0.9991304278, "qwen": "Yes"}
{"id": "24950997", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=24950997", "title": "Flat honing", "text": "Flat honing is a metalworking grinding process used to provide high quality flat surfaces. It combines the speed of grinding or honing with the precision of lapping. It has also been known under the terms high speed lapping and high precision grinding.\nOrigin of term.\nThe term is derived from honing cylinders and holes. A flat workpiece surface is processed, hence the word flat; the word honing is used because the cutting speed is low compared to grinding. A fixed abrasive is used to provide accuracy and optical appearance of the surface finish. Sometimes it is also called fine grinding or surface grinding using planetary kinematics.\nHistory.\nThe technology is relatively young, having appeared in the 1980s. In the industry, production lapping is being replaced by flat honing in an ever-expanding array of applications. The flat honing process allows for an equivalent quality result, but at a significant reduction in manufacturing costs per workpiece. Savings result from reduced process times and the ease of workpiece cleaning. However, more and more parts are processed directly from their blank operation (sintered, injected, punched, sawed, or similar) with highly precise tolerances and accuracy (flatness and roughness).\nMethod.\nThe removal of the material is done by using geometrically undefined cutting edges (grain bound) that are held together in large working wheels with a thin layer of abrasive. The workpieces are held in toothed carriers (plastic, steel) that are driven by two horizontal pin rings. The full workpiece surface is in constant contact with an abrasive wheel.\nThere are two different processes: Single and double sided machining.\nThe working wheel and the carriers are driven by different relative movements between the workpiece and the abrasive wheel. The rotation of the inner pin ring against the working wheel generates the stock removal. The operation itself will be flushed continually (mostly with oil) to ensure the clean working wheel does not become contaminated with grinding sludge.\nAbrasive.\nMost working wheels contain abrasive grains of synthetic diamond or cubic boron nitride (CBN). The grain shape, grain coating and the grain size are other important components for an optimal working process.\nBond.\nThe bond has the task of holding the individual grains together until they become dull. Type and quantity of the binder used affects both the hardness and the abrasive properties of the working wheels. The outbreak of the abrasive grain is called self-sharpening.\nLayout of flat honing wheels.\nFlat honing requires an exclusive wheel suitable for the type of material being processed. Flat honing wheels are available with full faced layers of abrasive although grooves of different geometry can be introduced to enhance a better removal of material. These abrasives are fixed onto a steel plate. For vitrified bonded flat honing wheels, round or hexagonal pellets are used and are fixed to the steel plate with a special adhesive. The spaces between the pellets or segments are used to reduce the contact between the workpiece and the abrasive wheel. They also cool and lubricate the process. All types of flat honing wheels can vary in grain concentration and grain size along the area of the wheel which results in an even wear over the complete wheel.\nCooling and flushing.\nThe main task of the coolant is to aid in the dissipation of heat from removed stock. It also reduces the friction between the abrasive and the workpiece. Therefore, proper wetting, adhesion, pressure, temperature resistance, and corrosion protection are all factors when selecting a coolant. Oil (mineral or diester based) is used as the preferred cooling and flushing media. Water emulsions may also be used.\nApplications.\nDue to the tension-free reception of loose parts in the carriers, virtually any solid material can be processed. The application range is very wide, from a soft to a very hard material (thermoplastic plastic to sapphire or ceramic).\nExamples are vane pump parts made of polyphenylene sulfide (PPS), ceramic insert made of SiNi, watch windows, sapphire LED wafers, bearing rings, vane pumps, gear steel, cutting knives and carbide.\nThe surface is similar to the typical honing crosshatch, this leads to good tribological properties and fine roughness. The low subsurface damage will have a positive impact on subsequent polishing processes (CMP, etching).", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "24951945", "revid": "21857263", "url": "https://en.wikipedia.org/wiki?curid=24951945", "title": "Steel abrasive", "text": "Steel abrasives are steel particles that are used as abrasive or peening media. They are usually available in two different shapes (shot and grit) that address different industrial applications.\nSteel shot refers to spherical grains made of molten steel through an atomization (\"granulation\") process, available in different sizes and hardnesses.\nSteel grit characterizes grains with a predominantly angular shape. These grains are obtained by crushing steel shot, therefore they exhibit sharp edges and broken sections. Harder than steel shot, it is also available in different sizes and hardnesses.\nProperties.\nMost steel abrasives are made of a high-carbon steel composition, the best compromise between mechanical properties, efficiency and durability. The most important properties for steel abrasives are hardness, grain size and shape, toughness and cleanliness (lack of oxides, contaminants, etc.).\nRecyclability and environmental impact.\nThe recyclability of steel shot and grit ranges between 2000 and 3000 cycles. Due to its high recyclability level, steel shot and grit tend to generate less waste when compared to other expendable abrasives.\nHardness.\nSteel shot or grit is usually available at different hardness levels, ranging between 40 and 65 on the Rockwell scale (400 to 850 on the Vickers hardness scale).\nIndustrial applications.\nCleaning.\nSteel shot and grit are used in cleaning applications for removal of loose material on metal surfaces. This type of cleaning is common in automotive industry (motor blocks, cylinder heads, etc.).\nSurface preparation.\nSurface preparation is a series of operations including cleaning and physical modification of a surface. Steel shot and grit are used in a surface preparation process for cleaning metal surfaces which are covered with mill scale, dirt, rust, or paint coatings and for physically modifying the metal surface such as creating roughness for better application of paint and coating. The steel shots are generally employed in shot blasting machines, first made by US-based company Wheelabrator in 1932. In China, shot blasting machines were built around the 1950s, Qinggong Machinery is one of the earliest manufacturers in that industry.\nStone cutting.\nSteel grit is used in cutting hard stones, such as granite. The grit is used in large multi-blade frames which cut the blocks of granite into thin slices.\nShot peening.\nShot peening is the repeated striking of a metal surface by hard shot particles. These multiple impacts produce a deformation on the metal surface, but also improve the durability of the metal part. The media used in this application is spherical rather than angular. The reason is that spherical shots are more resistant to the fracture which happens due to the striking impact.and distributes the peening force more evenly and reduces the risk of stress risers. This makes steel shots a better choice for shot peening in aircraft engineering, where the peened surface must be strong and fatigue-resistant.\nDebarring & Descaling.\nDustless Steel shot is being used in combination with Steel shots in range of 0.18 mm - 2.80 mm in size for descaling and debarring the surface before further process\nIndustrial uses.\nSteel shot and grit address numerous sectors since cleaning, surface preparation or shot peening applications are used by many industries as a part of their construction, renovation or repair processes. The main industrial sectors employing steel abrasives are:\nProduction.\nThe annual steel abrasive production in the world is estimated to be above 1 million tonnes, the world’s largest producer being Winoa Group (previously known as Wheelabrator Allevard) by production and capacity.", "Engineering,_Manufacturing": 1.0000071526, "qwen": "Yes"}
{"id": "507190", "revid": "4173550", "url": "https://en.wikipedia.org/wiki?curid=507190", "title": "Steel and tin cans", "text": "A steel can, tin can, tin (especially in British English, Australian English, Canadian English and South African English), steel packaging, or can is a container for the distribution or storage of goods, made of thin metal. Many cans require opening by cutting the \"end\" open; others have removable covers. They can store a broad variety of contents: food, beverages, oil, chemicals, etc. Steel cans are made of tinplate (tin-coated steel) or of tin-free steel. In some dialects, even aluminium cans are called \"tin cans\".\nSteel cans are highly recyclable, with around 65% of steel cans being recycled.\nHistory.\nThe tin canning process was conceived by the Frenchman Philippe de Girard, who had British merchant Peter Durand patent the idea in 1810. The canning concept was based on experimental food preservation work in glass containers the year before by the French inventor Nicholas Appert. Durand did not pursue food canning, but, in 1812, sold his patent to two Englishmen, Bryan Donkin and John Hall, who refined the process and product, and set up the world's first commercial canning factory on Southwark Park Road, London. By 1813 they were producing their first tin canned goods for the Royal Navy. By 1820, tin canisters or cans were being used for gunpowder, seeds, and turpentine.\nEarly tin cans were sealed by soldering with a tin–lead alloy, which could lead to lead poisoning.\nIn 1901 in the United States, the American Can Company was founded, at the time producing 90% of the tin cans in the United States.\nCanned food in tin cans was already quite popular in various countries when technological advancements in the 1920s lowered the cost of the cans even further. In 1935, the first beer in metal cans was sold; it was an instant sales success.\nDescription.\nMost cans are right circular cylinders with identical and parallel round tops and bottoms with vertical sides. However, cans for small volumes or particularly-shaped contents, the top and bottom may be rounded-corner rectangles or ovals. Other contents may suit a can that is somewhat conical in shape.\nFabrication of most cans results in at least one \"rim\"—a narrow ring slightly larger than the outside diameter of the rest of the can. The flat surfaces of rimmed cans are recessed from the edge of any rim (toward the middle of the can) by about the width of the rim; the inside diameter of a rim, adjacent to this recessed surface, is slightly smaller than the inside diameter of the rest of the can.\nThree-piece can construction results in top and bottom rims. In two-piece construction, one piece is a flat top and the other a deep-drawn cup-shaped piece that combines the (at least roughly) cylindrical wall and the round base. Transition between wall and base is usually gradual. Such cans have a single rim at the top. Some cans have a separate cover that slides onto the top or is hinged.\nTwo piece steel cans can be made by \"drawing\" to form the bottom and sides and adding an \"end\" at the top: these do not have side seams. Cans can be fabricated with separate slip-on, or friction fit covers and with covers attached by hinges. Various easy opening methods are available.\nIn the mid-20th century, a few milk products were packaged in nearly rimless cans, reflecting different construction; in this case, one flat surface had a hole (for filling the nearly complete can) that was sealed after filling with a quickly solidifying drop of molten solder. Concern arose that the milk contained unsafe levels of lead leached from this solder plug.\nAdvantages of steel cans.\nA number of factors make steel cans ideal containers for beverages. Steel cans are stronger than cartons or plastic, and less fragile than glass, protecting the product in transit and preventing leakage or spillage, while also reducing the need for secondary packaging.\nSteel and aluminium packaging offer 100% barrier protection against light, water and air, and metal cans without resealable closures are among the most tamper-evident of all packaging materials. Steel cans preserve and protect the product from damage by light, oxidation, extremes of temperature and contamination, safeguarding flavour, appearance and quality from factory to final consumer. Food and drink packed in steel cans has equivalent vitamin content to freshly prepared, without needing preserving agents. Steel cans also extend the product's shelf-life, allowing longer sell-by and use-by dates and reducing waste.\nAs an ambient packaging medium, steel cans do not require cooling in the supply chain, simplifying logistics and storage, and saving energy and cost. At the same time, steel's relatively high thermal conductivity means canned drinks chill much more rapidly and easily than those in glass or plastic bottles.\nA World Steel Association initiative, Choose Steel, is encouraging the use of steel for beverage cans.\nMaterials.\nNo cans currently in wide use are composed primarily or wholly of tin; that term rather reflects the nearly exclusive use in cans, until the second half of the 20th century, of tinplate steel, which combined the physical strength and relatively low price of steel with the corrosion resistance of tin. Depending on contents and available coatings, some canneries still use tin-free steel.\nIn some local dialects, any metal can, even aluminium, might be called a \"tin can\". Use of aluminium in cans began in 1957. Aluminium is less costly than tin-plated steel but offers the same resistance to corrosion in addition to greater malleability, resulting in ease of manufacture; this gave rise to the two-piece can, where all but the top of the can is simply stamped out of a single piece of aluminium, rather than laboriously constructed from three pieces of steel.\nA can traditionally has a printed paper or plastic label glued to the outside of the curved surface, indicating its contents. Some labels contain additional information, such as recipes, on the reverse side. More recently labels are sometimes printed directly onto the metal before or after the metal sheet is formed into the individual cans.\nIn November 1991, US can manufacturers voluntarily eliminated lead seams in food cans. However, imported food cans continued to include lead soldered seams. In 1995, the US FDA issued a rule prohibiting lead soldered food cans, including both domestic and imported food cans.\nIn modern times, the majority of food cans in the UK have been lined with a plastic coating containing bisphenol A (BPA). The coating prevents acids and other substances from corroding the tin or aluminium of the can, but leaching of BPA into the can's contents was investigated as a potential health hazard.\nStandard sizes.\nCans come in a variety of shapes and sizes. Walls are often stiffened with rib bulges, especially on larger cans, to help the can resist dents that can cause seams to split.\nCan sizes in the United States have an assortment of designations and sizes. For example, size 7/8 contains one serving of half a cup with an estimated weight of 4 ounces; size 1 \"picnic\" has two or three servings totalling one and a quarter cups with an estimated weight of 10 ounces; size 303 has four servings totalling 2 cups weighing 15 ounces; and size 10 cans, most widely used by food services selling to cafeterias and restaurants, have twenty-five servings totalling 13 cups with an estimated weight of 103 ounces (size of a roughly 3 pound coffee can). These are U.S. customary cups, not British Imperial standard.\nIn the United States, cook books sometimes reference cans by size. The Can Manufacturers Institute defines these sizes, expressing them in three-digit numbers, as measured in whole and sixteenths of an inch for the container's nominal outside dimensions: a 307 × 512 would thus measure 3 and 7/16\" in diameter by 5 and 3/4\" (12/16\") in height. Older can numbers are often expressed as single digits, their contents being calculated for room-temperature water as approximately eleven ounces (#1 \"picnic\" can), twenty ounces (#2), thirty-two ounces (#3), fifty-eight ounces (#5), and one-hundred-ten ounces (#10 \"coffee\" can).\nIn parts of the world using the metric system, tins are made in 250, 500, 750 ml (millilitre) and 1 L (litre) sizes (250 ml is approximately 1 cup or 8 ounces). Cans imported from the US often have odd sizes such as 3.8 L (1 US gallon), 1.9 L (1/2 US gallon), and 946 ml (2 US pints / 1 quart).\nIn the UK and Australia, cans are usually measured by net weight. A standard size tin can holds roughly 400 g; though the weight can vary between 385 g and 425 g depending on the density of the contents. The smaller half sized can holds roughly 200 g, typically varying between 170 g and 225 g.\nFabrication of cans.\nRimmed three-piece can construction involves several stages;\nDouble seam rims are crucial to the joining of the wall to a top or bottom surface. An extremely tight fit between the pieces must be accomplished to prevent leakage; the process of accomplishing this radically deforms the rims of the parts. Part of the tube that forms the wall is bent, almost at its end, turning outward through 90 degrees, and then bent further, toward the middle of the tube, until it is parallel to the rest of the tube, a total bend of 180 degrees.\nThe outer edge of the flat piece is bent against this toward the middle of the tubular wall, until parallel with the wall, turning inward through 90 degrees. The edge of bent portion is bent further through another 90 degrees, inward now toward the axis of the tube and parallel to the main portion of the flat piece, making a total bend of 180 degrees. It is bent far enough inward that its circular edge is now slightly \"smaller\" in diameter than the edge of the tube. Bending it yet further, until it is parallel with the tube's axis, gives it a total bend of 270 degrees. It now envelops the outward rim of the tube.\nLooking outward from the axis of the tube, the first surface is the unbent portion of the tube. Slightly further out is a narrow portion of the top, including its edge. The outward-bent portion of the tube, including its edge, is still slightly further out. Furthest out is the 90-degree-bent portion of the flat surface.\nThe combined interacting forces, as the portion of the flat surface adjacent to the interior of the tube is indented toward the middle of the tube and then outward \"forward\" the axis of the tube, and the other bent portions of the flat piece and the tube are all forced \"toward\" the axis of the tube, drives these five thicknesses of metal against each other from inside and out, forming a \"dry\" joint so tight that welding or solder is not needed to strengthen or seal it. Illustrations of this process can be found on pages 20–22 of the FAO Fisheries Technical Paper 285 \"Manual on fish canning\" located here.\nDesign and manufacture.\nSteel for can making.\nThe majority of steel used in packaging is tinplate, which is steel that has been coated with a thin layer of tin, whose functionality is required for the production process. The tin layer is usually applied by electroplating.\nTwo-piece steel can design.\nMost steel beverage cans are two-piece designs, made from 1) a disc re-formed into a cylinder with an integral end, double-seamed after filling and 2) a loose end to close it. Steel cans are made in many different diameters and volumes, with opening mechanisms that vary from ring pulls and tab openers, to wide open mouths. Modern can making lines may produce up to 1000 cans per minute.\nDrawn-and-ironed (DWI) steel cans.\nThe process of re-forming sheet metal without changing its thickness is known as 'drawing'. Thinning the walls of a two-piece can by passing it through circular dies is called 'ironing'. Steel beverage cans are therefore generally referred to as drawn-and-ironed, or DWI, cans (sometimes D&I). The DWI process is used for making cans where the height is greater than the diameter, and is particularly suited to making large volumes of cans of the same basic specification.\nSteel can wall thicknesses are now 30% thinner and weigh 40% less than 30 years ago, reducing the amounts of raw materials and energy required to make them. They are also up to 40% thinner than aluminium.\nMagnetic properties.\nSteel is a ferrous metal and is therefore magnetic. For beverage packaging this is unique. This allows the use of magnetic conveyor systems to transfer empty cans through the filling and packing processes, increasing accuracy and reducing potential spillage and waste. In recycling facilities, steel cans may be readily separated from other waste using magnetic equipment including cross-belt separators, also known as overband magnets, and drum magnets.\nOpening cans.\nThe first cans were heavy-weight containers that required ingenuity to open, with implements such as knives. Not until several years later, after can manufacturers started using thinner metal sheets, were any dedicated can openers developed.\nWhile beverage cans or cans of fluid such as broth can merely be punctured to remove the product, solid or semisolid contents require removing one end of the can. This can be accomplished with a heavy knife or other sharp tool—but can openers are much more convenient.\nSome cans, such as those used for sardines, have a specially scored lid so that the user can break out the metal by the leverage of winding it around a slotted twist-key or church key. Until the mid-20th century, some sardine tins had solder-attached lids, and the twist-key or church key worked by forcing the solder joint apart.\nThe advent of pull tabs in beverage cans spread to the canning of various food products, such as pet food or nuts (and non-food products such as motor oil and tennis balls). The ends are known as \"easy open\" lids because they open without any tools or implements. An additional innovation developed for specifically for food cans uses a tab that is bent slightly upwards, creating a larger surface area for easier finger access.\nCans can be made with easy open features. Some cans have screw caps for pouring liquids and resealing. Some have hinged covers or slip-on covers for easy access. Paint cans often have a removable plug on the top for access and for reclosing.\nRecycling and re-use.\nSteel from cans and other sources is the most recycled packaging material. Around 65% of steel cans are recycled. In the United States, 63% of steel cans are recycled, compared to 52% of aluminium cans. In Europe, the recycling rate in 2016 is 79.5%.\nMost can recycling occurs at the smelters, but individual consumers also directly reuse cans in various ways. For instance some people use two tin cans to form a camp or survival stove to cook small meals.\nSustainability and recycling of steel beverage cans.\nSteel recycling.\nFrom an ecological perspective, steel may be regarded as a closed-loop material: post-consumer waste can be collected, recycled and used to make new cans or other products. Each tonne of scrap steel recycled saves 1.5 tonnes of CO2, 1.4 tonnes of iron ore and 740 kg of coal. Steel is the world's most recycled material, with more than 85% of all the world's steel products being recycled at the end of their life: an estimated 630 million tonnes of steel scrap were recycled in 2017, saving 945 million tonnes of CO2.\nSteel can recycling.\nA steel can can be recycled again and again without loss of quality; however, for the food grade steel it's required to remove tin from the scrap metal, which is done by way of electrochemistry: the tin is leached from a high pH solution at low negative voltage. \nRecycling a single can saves the equivalent power for one laundry load, 1 hour of TV or 24 hours of lighting (10W LED bulb).\nSteel beverage cans are recycled by being melted down in an electric arc furnace or basic oxygen furnace.\nMost steel cans also carry some form of recycling identification such as the Metal Recycles Forever Mark Recyclable Steel and the Choose Steel campaign logo. There is also a campaign in Europe called Every Can Counts, encouraging can recycling in the workplace \nSmaller carbon footprint.\nAll beverage packaging creates CO2 emissions at every stage in the production process, from raw material extraction, processing and manufacture through to recycling. However, steel cans are an ecological top performer, as cans can always be recycled. The steel industry needs the used cans and will use them in the production of new steel product. By recycling the cans and closing the loop, CO2 emissions are dramatically reduced. There is also the potential for higher global steel recycling rates as consumers become more aware of the benefits.\nHealth issues.\nDissolution of tin into the food.\nTin is corrosion resistant, but acidic food like fruits and vegetables can corrode the tin layer. Nausea, vomiting, and diarrhea have been reported after ingesting canned food containing 200 mg/kg of tin. A 2002 study showed that 99.5% of 1200 tested cans contained below the UK regulatory limit of 200 mg/kg of tin, an improvement over most previous studies largely attributed to the increased use of fully lacquered cans for acidic foods, and concluded that the results do not raise any long term food safety concerns for consumers. The two non-compliant products were voluntarily recalled.\nEvidence of tin impurities can be indicated by color, as in the case of pears, but lack of color change does not guarantee that a food is not tainted with tin.\nBisphenol-A.\nBisphenol-A (BPA) is a controversial chemical compound present in commercially available tin can plastic linings and transferred to canned food. The inside of the can is coated with an epoxy coating, in an attempt to prevent food or beverage from coming into contact with the metal. The longer food is in a can, and the warmer and more acidic it is, the more BPA leaches into it. In September 2010, Canada became the first country to declare BPA a toxic substance. In the European Union and Canada, BPA use is banned in baby bottles.\nThe FDA does not regulate BPA (see BPA controversy#Public health regulatory history in the United States). Several companies, like Campbell's Soup, announced plans to eliminate BPA from the linings of their cans, but have not said which chemical they plan to replace it with. (See BPA controversy#Chemical manufacturers reactions to bans.)", "Engineering,_Manufacturing": 0.99916327, "qwen": "Yes"}
{"id": "507363", "revid": "45857236", "url": "https://en.wikipedia.org/wiki?curid=507363", "title": "Digital printing", "text": "Digital printing is a method of printing from a digital-based image directly to a variety of media. It usually refers to professional printing where small-run jobs from desktop publishing and other digital sources are printed using large-format and/or high-volume laser or inkjet printers.\nDigital printing has a higher cost per page than more traditional offset printing methods, but this price is usually offset by avoiding the cost of all the technical steps required to make printing plates. It also allows for on-demand printing, short turnaround time, and even a modification of the image (variable data) used for each impression. The savings in labor and the ever-increasing capability of digital presses means that digital printing is reaching the point where it can match or supersede offset printing technology's ability to produce larger print runs of several thousand sheets at a low price.\nProcess.\nThe greatest difference between digital printing and analog methods, such as lithography, flexography, gravure, and letterpress, is that in digital printing (introduced in the 1980s) there is no need to replace the printing plate, whereas in analog printing the plates are repeatedly replaced. This results in quicker turnaround time and lower cost in digital printing, but typically a loss of detail in most commercial digital printing processes. The most popular methods include inkjet and laser printers, which deposit pigment and toner, respectively, onto substrates, such as paper, canvas, glass, metal, and marble.\nIn many of the processes, the ink or toner does not permeate the substrate, as does conventional ink, but forms a thin layer on the surface that may be additionally adhered to the substrate by a fuser fluid with thermal (toner) or ultraviolet curing (ink).\nDigital printing methods of note.\nFine art inkjet printing.\nFine art digital inkjet printing is printing from a computer image file directly to an inkjet printer as a final output. It evolved from digital proofing technology from Kodak, 3M, and other major manufacturers, with artists and other printers trying to adapt these dedicated prepress proofing machines to fine-art printing. There was experimentation with many of these types of printers, the most notable being the IRIS printer, initially adapted to fine-art printing by programmer David Coons, and adopted for fine-art work by Graham Nash at his Nash Editions printing company in 1991. Initially, these printers were limited to glossy papers, but the IRIS Graphics printer allowed the use of a variety of papers that included traditional and non-traditional media. The IRIS printer was the standard for fine art digital printmaking for many years, and is still in use today, but has been superseded by large-format printers from other manufacturers such as Epson and HP that use fade-resistant, archival inks (pigment-based, as well as newer solvent-based inks), and archival substrates specifically designed for fine-art printing.\nSubstrates in fine art inkjet printmaking include traditional fine-art papers such as Rives BFK, Arches watercolor paper, treated and untreated canvas, experimental substrates (such as metal and plastic), and fabric.\nFor artists making reproductions of their original work, inkjet printing is more expensive on a per-print basis than the traditional four-color offset lithography, but with inkjet printing the artist does not have to pay for the expensive printing-plate setup or the marketing and storage needed for large four-color offset print runs. Inkjet reproductions can be printed and sold individually in accordance with demand. Inkjet printing has the added advantage of allowing artists to take total control of the production of their images, including the final color correction and the substrates being used, with some artists owning and operating their own printers.\nDigital inkjet printing also allows for the output of digital art of all types as finished pieces or as an element in a further art piece. Experimental artists often add texture or other media to the surface of a final print, or use it as part of a mixed-media work. Many terms for the process have been used over the years, including \"digigraph\" and \"giclée\". Thousands of print shops and digital printmakers now offer services to painters, photographers, and digital artists around the world.\nNotable digital laser exposure.\nDigital images are exposed onto true, light sensitive photographic paper with lasers and processed in photographic developers and fixers. These prints are true photographs and have continuous tone in the image detail. The archival quality of the print is as high as the manufacturer's rating for any given photo paper used. In large format prints, the greatest advantage is that, since no lens is used, there is no vignetting or detail distortion in the corners of the image.\nDigital printing technology has grown significantly over the past few years with substantial developments in quality and sheet sizes.\nDigital cylinder printing.\nDigital cylinder printing is when a machine directly lays ink onto a curved surface that usually is the wall of an object that has a circular cross section, and a constant, tapered, or variable diameter. Digital cylinder printing is a method of reproducing black-and-white or full-color images and text onto cylindrical objects, typically promotional products, through use of digital imaging systems.\nThe digital process is by definition faster than conventional screen printing, because it requires fewer production steps and less set-up time for multiple colors and more complex jobs. This in turn enables reduced run lengths.\nThe ability of digital cylinder printing machines to print full color in one pass, including primers, varnishes and specialty inks, enables multiple design techniques, which include:\nFull-wrap cylindrical printing also benefits from seamless borders with no visual overlap. For ease of print file preparation, original design artwork should be able to be imaged on cylinders and tapered items without the need for manipulation or distortion; i.e., flat images will print to scale on a curved surface, with software automatically making the adjustment. The more advanced systems available on the market can handle these requirements.\nThe digital cylindrical printing process involves inserting a cylinder-shaped item, or part, into a fixture, which securely holds it in place. The part then travels under a print head mechanism in which tiny droplets of CMYK (cyan, magenta, yellow, and black) inks are released in a specific pattern to form an image. Typically, one part is printed at a time and can require from 8 to 45 seconds to complete, depending on artwork complexity and quality. It is then finished with a UV coating to add a glossy finish and protect it from abrasion.\nThere are three different imaging techniques used by digital cylinder printing machines: multi-pass, single pass, and helical printing.\nMulti-Pass: Multi-pass printing is when the print heads or printed object move axially in steps down the part, like a flatbed printer. The move time is inefficient and can lead to stitching artifacts between moves.\nSingle Pass: Single pass involves using an array of print heads to print the full image length with a single revolution of the printed object. Different colors are usually printed at different stations, leading to higher cost, increased complexity, and sensitivity to print nozzle drop-outs.  \nHelical Printing: Helical printing is a hybrid method between the single-pass and multi-pass approaches. Image data is mapped to allow continuous imaging in a helical pattern with a limited number of print heads. Users can optimize the print resolution, speed, and curing controls to optimize image quality or choose higher speed if quality isn’t critical. Tapers can be imaged at high speed and curved vessels can be managed through the range of controls offered.\nItems that can be printed using digital cylindrical processes include cups, tumblers, thermos bottles, bottles, makeup containers, machine parts, carrier tubes, pens, tubes, jars and others.\nApplications.\nDigital printing has many advantages over traditional methods. Some applications of note include:\npersonalization of printed materials", "Engineering,_Manufacturing": 0.9769923687, "qwen": "Yes"}
{"id": "509033", "revid": "1169675864", "url": "https://en.wikipedia.org/wiki?curid=509033", "title": "Rivet", "text": "A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite the head is called the \"tail\". On installation, the rivet is placed in a punched or drilled hole, and the tail is \"upset\" or \"bucked\" (i.e., deformed), so that it expands to about 1.5 times the original shaft diameter, holding the rivet in place. In other words, the pounding or pulling creates a new \"head\" on the tail end by smashing the \"tail\" material flatter, resulting in a rivet that is roughly a dumbbell shape. To distinguish between the two ends of the rivet, the original head is called the \"factory head\" and the deformed end is called the \"shop head\" or buck-tail.\nBecause there is effectively a head on each end of an installed rivet, it can support tension loads. However, it is much more capable of supporting shear loads (loads perpendicular to the axis of the shaft).\nFastenings used in traditional wooden boat building, such as copper nails and clinch bolts, work on the same principle as the rivet but were in use long before the term \"rivet\" was introduced and, where they are remembered, are usually classified among nails and bolts respectively.\nHistory.\nRivet holes have been found in Egyptian spearheads dating back to the Naqada culture of between 4400 and 3000 B.C. Archeologists have also uncovered many Bronze Age swords and daggers with rivet holes where the handles would have been. The rivets themselves were essentially short rods of metal, which metalworkers hammered into a pre-drilled hole on one side and deformed on the other to hold them in place.\nTypes.\nThere are several types of rivets, designed to meet different cost, accessibility, and strength requirements:\nSolid/round head rivets.\nSolid rivets are one of the oldest and most reliable types of fasteners, having been found in archaeological findings dating back to the Bronze Age. Solid rivets consist simply of a shaft and head that are deformed with a hammer or rivet gun. A rivet compression or crimping tool can also deform this type of rivet. This tool is mainly used on rivets close to the edge of the fastened material since the tool is limited by the depth of its frame. A rivet compression tool does not require two people and is generally the most foolproof way to install solid rivets.\nSolid rivets are used in applications where reliability and safety count. A typical application for solid rivets can be found within the structural parts of aircraft. Hundreds of thousands of solid rivets are used to assemble the frame of a modern aircraft. Such rivets come with rounded (universal) or 100° countersunk heads. Typical materials for aircraft rivets are aluminium alloys (2017, 2024, 2117, 7050, 5056, 55000, V-65), titanium, and nickel-based alloys (e.g., Monel). Some aluminium alloy rivets are too hard to buck and must be softened by solution treating (precipitation hardening) prior to being bucked. \"Ice box\" aluminium alloy rivets harden with age, and must likewise be annealed and then kept at sub-freezing temperatures (hence the name \"ice box\") to slow the age-hardening process. Steel rivets can be found in static structures such as bridges, cranes, and building frames.\nThe setting of these fasteners requires access to both sides of a structure. Solid rivets are driven using a hydraulically, pneumatically, or electromagnetically actuated squeezing tool or even a handheld hammer. Applications where only one side is accessible require \"blind\" rivets.\nSolid rivets are also used by some artisans in the construction of modern reproduction of medieval armour, jewellery and metal couture.\nHigh-strength structural steel rivets.\nUntil relatively recently, structural steel connections were either welded or riveted. High-strength bolts have largely replaced structural steel rivets. Indeed, the latest steel construction specifications published by AISC (the 14th Edition) no longer cover their installation. The reason for the change is primarily due to the expense of skilled workers required to install high-strength structural steel rivets. Whereas two relatively unskilled workers can install and tighten high-strength bolts, it normally takes four skilled workers to install rivets (warmer, catcher, holder, basher).\nAt a central location near the areas being riveted, a furnace was set up. Rivets were placed in the furnace and heated to approximately 900 °C or \"cherry red\". The rivet warmer or \"cook\" used tongs to remove individual rivets and throw them to a catcher stationed near the joints to be riveted. The \"catcher\" (usually) caught the rivet in a leather or wooden bucket with an ash-lined bottom. The catcher inserted the rivet into the hole to be riveted, then quickly turned to catch the next rivet. The \"holder up\" or \"holder on\" would hold a heavy \"bucking bar\" or dolly or another (larger) pneumatic jack against the round \"shop head\" of the rivet, while the riveter (sometimes two riveters) applied a hammer or pneumatic rivet hammer With a \"rivet set\" to the tail of the rivet, making it mushroom against the joint forming the \"field head\" into its final domed shape. Alternatively, the buck is hammered more or less flush with the structure in a counter-sunk hole. Before the use of pneumatic hammers, e.g. in the construction of RMS \"Titanic\", the man who hammered the rivet was known as the \"basher\". As the hot rivet was well above its service temperature when the field head was forged, it was unable to create significant tension. However, upon cooling, the rivet contracted axially exerting the clamping force on the joint. \nThe last commonly used high-strength structural steel rivets were designated ASTM A502 Grade 1 rivets.\nSuch riveted structures may be insufficient to resist seismic loading from earthquakes if the structure was not engineered for such forces, a common problem of older steel bridges. This is because a hot rivet cannot be properly heat treated to add strength and hardness. In the seismic retrofit of such structures, it is common practice to remove critical rivets with an oxygen torch, precision ream the hole, then insert a machined and heat-treated bolt.\nSemi-tubular rivets.\nSemi-tubular rivets (also known as tubular rivets) are similar to solid rivets, except they have a partial hole (opposite the head) at the tip. The purpose of this hole is to reduce the amount of force needed for application by rolling the tubular portion outward. The force needed to apply a semi-tubular rivet is about 1/4 of the amount needed to apply a solid rivet. Tubular rivets are sometimes preferred for pivot points (a joint where movement is desired) since the swelling of the rivet is only at the tail. The type of equipment used to apply semi-tubular rivets ranges from prototyping tools to fully automated systems. Typical installation tools (from lowest to highest price) are hand set, manual squeezer, pneumatic squeezer, kick press, impact riveter, and finally PLC-controlled robotics. The most common machine is the impact riveter and the most common use of semi-tubular rivets is in lighting, brakes, ladders, binders, HVAC duct-work, mechanical products, and electronics. They are offered from 1/16-inch (1.6 mm) to 3/8-inch (9.5 mm) in diameter (other sizes are considered highly special) and can be up to 8 inches (203 mm) long. A wide variety of materials and platings are available, most common base metals are steel, brass, copper, stainless, aluminum and the most common platings are zinc, nickel, brass, tin. Tubular rivets are normally waxed to facilitate proper assembly. An installed tubular rivet has a head on one side, with a rolled-over and exposed shallow blind hole on the other.\nBlind rivets.\nBlind rivets, commonly referred to as \"pop\" rivets (POP is the brand name of the original manufacturer, now owned by Stanley Engineered Fastening, a division of Stanley Black & Decker) are tubular and are supplied with a nail-like mandrel through the center which has a \"necked\" or weakened area near the head. The rivet assembly is inserted into a hole drilled through the parts to be joined and a specially designed tool is used to draw the mandrel through the rivet. The compression force between the head of the mandrel and the tool expands the diameter of the tube throughout its length, locking the sheets being fastened if the hole was the correct size. The head of the mandrel also expands the blind end of the rivet to a diameter greater than that of the drilled hole, compressing the fastened sheets between the head of the rivet and the head of the mandrel. At a predetermined tension, the mandrel breaks at the necked location. With open tubular rivets, the head of the mandrel may or may not remain embedded in the expanded portion of the rivet, and can come loose at a later time. More expensive closed-end tubular rivets are formed around the mandrel so the head of the mandrel is always retained inside the blind end after installation. \"Pop\" rivets can be fully installed with access to only one side of a part or structure.\nPrior to the invention of blind rivets, installation of a rivet typically required access to both sides of the assembly: a rivet hammer on one side and a bucking bar on the other side. In 1916, Royal Navy reservist and engineer Hamilton Neil Wylie filed a patent for an \"improved means of closing tubular rivets\" (granted May 1917). In 1922 Wylie joined the British aircraft manufacturer Armstrong-Whitworth Ltd to advise on metal construction techniques; here he continued to develop his rivet design with a further 1927 patent that incorporated the pull-through mandrel and allowed the rivet to be used \"blind\". By 1928, the George Tucker Eyelet Company, of Birmingham, England, produced a \"cup\" rivet based on the design. It required a separate GKN mandrel and the rivet body to be hand-assembled prior to use for the building of the Siskin III aircraft. Together with Armstrong-Whitworth, the Geo. Tucker Co. further modified the rivet design to produce a one-piece unit incorporating a mandrel and rivet. This product was later developed in aluminium and trademarked as the \"POP\" rivet. The United Shoe Machinery Co. produced the design in the U.S. as inventors such as Carl Cherry and Lou Huck experimented with other techniques for expanding solid rivets.\nThey are available in flat head, countersunk head, and modified flush head with standard diameters of 1/8, 5/32, and 3/16 inch. Blind rivets are made from soft aluminum alloy, steel (including stainless steel), copper, and Monel.\nThere are also \"\", which are designed to take shear and tensile loads.\nThe rivet body is normally manufactured using one of three methods:\nThere is a vast array of specialty blind rivets that are suited for high strength or plastic applications. Typical types include:\nInternally and externally locked structural blind rivets can be used in aircraft applications because, unlike other types of blind rivets, the locked mandrels cannot fall out and are watertight. Since the mandrel is locked into place, they have the same or greater shear-load-carrying capacity as solid rivets and may be used to replace solid rivets on all but the most critical stressed aircraft structures.\nThe typical assembly process requires the operator to install the rivet in the nose of the tool by hand and then actuate the tool. However, in recent years automated riveting systems have become popular in an effort to reduce assembly costs and repetitive disorders. The cost of such tools ranges from US$1,500 for auto-feed pneumatics to US$50,000 for fully robotic systems.\nWhile structural blind rivets using a locked mandrel are common, there are also aircraft applications using \"non-structural\" blind rivets where the reduced, but still predictable, strength of the rivet without the mandrel is used as the design strength. A method popularized by Chris Heintz of Zenith Aircraft uses a common flat-head (countersunk) rivet which is drawn into a specially machined nosepiece that forms it into a round-head rivet, taking up much of the variation inherent in hole size found in amateur aircraft construction. Aircraft designed with these rivets use rivet strength figures measured with the mandrel removed.\nOscar rivets.\nOscar rivets are similar to blind rivets in appearance and installation but have splits (typically three) along the hollow shaft. These splits cause the shaft to fold and flare out (similar to the wings on a toggle bolt's nut) as the mandrel is drawn into the rivet. This flare (or flange) provides a wide bearing surface that reduces the chance of rivet pull-out. This design is ideal for high-vibration applications where the back surface is inaccessible.\nA version of the Oscar rivet is the Olympic rivet which uses an aluminum mandrel that is drawn into the rivet head. After installation, the head and mandrel are shaved off flush resulting in an appearance closely resembling a brazier head-driven rivet. They are used in the repair of Airstream trailers to replicate the look of the original rivets.\nDrive rivet.\nA drive rivet is a form of blind rivet that has a short mandrel protruding from the head that is driven in with a hammer to flare out the end inserted in the hole. This is commonly used to rivet wood panels into place since the hole does not need to be drilled all the way through the panel, producing an aesthetically pleasing appearance. They can also be used with plastic, metal, and other materials and require no special setting tool other than a hammer and possibly a backing block (steel or some other dense material) placed behind the location of the rivet while hammering it into place. Drive rivets have less clamping force than most other rivets. Drive screws, possibly another name for drive rivets, are commonly used to hold nameplates into blind holes. They typically have spiral threads that grip the side of the hole.\nFlush rivet.\nA flush rivet is used primarily on external metal surfaces where good appearance and the elimination of unnecessary aerodynamic drag are important. A flush rivet takes advantage of a countersunk or dimpled hole; they are also commonly referred to as countersunk rivets. Countersunk or flush rivets are used extensively on the exterior of aircraft for aerodynamic reasons such as reduced drag and turbulence. Additional post-installation machining may be performed to perfect the airflow.\nFlush riveting was invented in America in the 1930s by Vladimir Pavlecka and his team at Douglas Aircraft. The technology was used by Howard Hughes in the design and production of his H-1 plane, the Hughes H-1 Racer.\nFriction-lock rivet.\nThese resemble an expanding bolt except the shaft snaps below the surface when the tension is sufficient. The blind end may be either countersunk ('flush') or dome-shaped.\nOne early form of blind rivet that was the first to be widely used for aircraft construction and repair was the Cherry friction-lock rivet. Originally, Cherry friction locks were available in two styles, hollow shank pull-through and self-plugging types. The pull-through type is no longer common; however, the self-plugging Cherry friction-lock rivet is still used for repairing light aircraft.\nCherry friction-lock rivets are available in two head styles, universal and 100-degree countersunk. Furthermore, they are usually supplied in three standard diameters, 1/8, 5/32 and 3/16 inch.\nA friction-lock rivet cannot replace a solid shank rivet, size for size. When a friction lock is used to replace a solid shank rivet, it must be at least one size larger in diameter because the friction-lock rivet loses considerable strength if its center stem falls out due to vibrations or damage.\nSelf-piercing rivets.\nSelf-pierce riveting (SPR) is a process of joining two or more materials using an engineered rivet. Unlike solid, blind and semi-tubular rivets, self-pierce rivets do not require a drilled or punched hole.\nSPRs are cold-forged to a semi-tubular shape and contain a partial hole to the opposite end of the head. The end geometry of the rivet has a chamfered poke that helps the rivet pierce the materials being joined. A hydraulic or electric servo rivet setter drives the rivet into the material, and an upsetting die provides a cavity for the displaced bottom sheet material to flow. The SPR process is described in here SPR process.\nThe self-pierce rivet fully pierces the top sheet material(s) but only partially pierces the bottom sheet. As the tail end of the rivet does not break through the bottom sheet it provides a water or gas-tight joint. With the influence of the upsetting die, the tail end of the rivet flares and interlocks into the bottom sheet forming a low profile button.\nRivets need to be harder than the materials being joined. they are heat treated to various levels of hardness depending on the material's ductility and hardness. Rivets come in a range of diameters and lengths depending on the materials being joined; head styles are either flush countersunk or pan heads.\nDepending on the rivet setter configuration, i.e. hydraulic, servo, stroke, nose-to-die gap, feed system etc., cycle times can be as quick as one second. Rivets are typically fed to the rivet setter nose from tape and come in cassette or spool form for continuous production.\nRiveting systems can be manual or automated depending on the application requirements; all systems are very flexible in terms of product design and ease of integration into a manufacturing process.\nSPR joins a range of dissimilar materials such as steel, aluminum, plastics, composites and pre-coated or pre-painted materials. Benefits include low energy demands, no heat, fumes, sparks or waste and very repeatable quality.\nCompression rivets.\nCompression rivets are commonly used for functional or decorative purposes on clothing, accessories, and other items. They have male and female halves that press together, through a hole in the material. \"Double cap rivets\" have aesthetic caps on both sides. \"Single cap rivets\" have caps on just one side; the other side is low profile with a visible hole. \"Cutlery rivets\" are commonly used to attach handles to knife blades and other utensils.\nSizes.\nRivets come in both inch series and metric series:\nThe main official standards relate more to technical parameters such as ultimate tensile strength and surface finishing than physical length and diameter. They are:\nImperial.\nRivet diameters are commonly measured in -inch increments and their lengths in -inch increments, expressed as \"dash numbers\" at the end of the rivet identification number. A \"dash 3 dash 4\" (XXXXXX-3-4) designation indicates a -inch diameter and -inch (or -inch) length. Some rivets lengths are also available in \"half sizes\", and have a dash number such as –3.5 ( inch) to indicate they are half-size. The letters and digits in a rivet's identification number that precede its dash numbers indicate the specification under which the rivet was manufactured and the head style. On many rivets, a size in 32nds may be stamped on the rivet head. Other makings on the rivet head, such as small raised or depressed dimples or small raised bars indicate the rivet's alloy.\nTo become a proper fastener, a rivet should be placed in a hole ideally 4–6 thousandths of an inch larger in diameter. This allows the rivet to be easily and fully inserted, then setting allows the rivet to expand, tightly filling the gap and maximizing strength.\nMetric.\nRivet diameters and lengths are measured in millimeters. Conveniently, the rivet diameter relates to the drill required to make a hole to accept the rivet, rather than the actual diameter of the rivet, which is slightly smaller. This facilitates the use of a simple drill-gauge to check both rivet and drill are compatible. For general use, diameters between 2 mm – 20 mm and lengths from 5 mm – 50 mm are common. The design type, material and any finish is usually expressed in plain language (often English).\nApplications.\nBefore welding techniques and bolted joints were developed, metal-framed buildings and structures such as the Eiffel Tower, Shukhov Tower and the Sydney Harbour Bridge were generally held together by riveting, as were automobile chassis. Riveting is still widely used in applications where light weight and high strength are critical, such as in an aircraft. Many sheet-metal alloys are preferably not welded as deformation and modification of material properties can occur.\nA large number of countries used rivets in the construction of armored tanks during World War II, including the M3 Lee (General Grant) manufactured in the United States. However, many countries soon learned that rivets were a large weakness in tank design since if a tank was hit by a large projectile it would dislocate the rivets and they would fly around the inside of the tank and injure or kill the crew, even if the projectile did not penetrate the armor. Some countries such as Italy, Japan, and Britain used rivets in some or all of their tank designs throughout the war for various reasons, such as lack of welding equipment or inability to weld very thick plates of armor effectively.\nBlind rivets are used almost universally in the construction of plywood road cases.\nCommon but more exotic uses of rivets are to reinforce jeans and to produce the distinctive sound of a sizzle cymbal.\nJoint analysis.\nThe stress and shear in a rivet are analyzed like a bolted joint. However, it is not wise to combine rivets with bolts and screws in the same joint. Rivets fill the hole where they are installed to establish a very tight fit (often called an interference fit). It is difficult or impossible to obtain such a tight fit with other fasteners. The result is that rivets in the same joint with loose fasteners carry more of the load—they are effectively stiffer. The rivet can then fail before it can redistribute load to the other loose-fit fasteners like bolts and screws. This often causes catastrophic failure of the joint when the fasteners \"unzip\". In general, a joint composed of similar fasteners is the most efficient because all fasteners reach capacity simultaneously.\nInstallation.\nSolid and semi-tubular rivets.\nThere are several methods for installing solid rivets.\nRivets small enough and soft enough are often \"bucked\". In this process, the installer places a rivet gun against the factory head and holds a bucking bar against the tail or a hard working surface. The bucking bar is a specially shaped solid block of metal. The rivet gun provides a series of high-impulse forces that upsets and work hardens the tail of the rivet between the work and the inertia of the bucking bar. Rivets that are large or hard may be more easily installed by squeezing instead. In this process, a tool in contact with each end of the rivet clinches to deform the rivet.\nRivets may also be upset by hand, using a ball-peen hammer. The head is placed in a special hole made to accommodate it, known as a rivet-set. The hammer is applied to the buck-tail of the rivet, rolling an edge so that it is flush against the material.\nTesting.\nSolid rivets for construction.\nA hammer is also used to \"ring\" an installed rivet, as a non-destructive test for tightness and imperfections. The inspector taps the head (usually the factory head) of the rivet with the hammer while touching the rivet and base plate lightly with the other hand and judges the quality of the audibly returned sound and the feel of the sound traveling through the metal to the operator's fingers. A rivet tightly set in its hole returns a clean and clear ring, while a loose rivet produces a recognizably different sound.\nTesting of blind rivets.\nA blind rivet has strength properties that can be measured in terms of shear and tensile strength. Occasionally rivets also undergo performance testing for other critical features, such as pushout force, break load and salt spray resistance. A standardized destructive test according to the Inch Fastener Standards is widely accepted.\nThe shear test involves installing a rivet into two plates at specified hardness and thickness and measuring the force necessary to shear the plates. The tensile test is basically the same, except that it measures the pullout strength. Per the IFI-135 standard, all blind rivets produced must meet this standard. These tests determine the strength of the rivet, and not the strength of the assembly. To determine the strength of the assembly a user must consult an engineering guide or the Machinery's Handbook.", "Engineering,_Manufacturing": 1.0000038147, "qwen": "Yes"}
{"id": "6395054", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=6395054", "title": "Pallet jack", "text": "A pallet jack, also known as a pallet truck, pallet pump, pump truck, scooter, dog, or jigger is a tool used to lift and move pallets. Pallet jacks are the most basic form of a forklift and are intended to move pallets within a warehouse.\nOperational principle.\nThe jack is steered by a tiller-like lever called a 'tow bar' that also acts on the pump piston for raising the forks. A small lever on the tow bar's steering handle releases the hydraulic fluid, causing the forks to lower. The steering wheels are located directly below the tow bar and support the jacking mechanism.\nThe front wheels inside the end of the forks are mounted on push rods attached to linkages that go to levers attached to the jack cylinder. As the hydraulic jack at the 'tiller' end is raised, the links force the wheels down, raising the forks vertically above the front wheels, raising the load upward until it clears the floor. The pallet is only lifted enough to clear the floor for subsequent travel. Oftentimes, pallet jacks are used to move and organize pallets inside a trailer, especially when there is no forklift truck access or availability.\nHistory.\nManual pallet jacks have existed since at least 1918. Early types lifted the forks and load only by mechanical linkages. More modern type uses a hand pumped hydraulic jack to lift.\nTypes.\nManual pallet jack.\nA manual pallet jack is a hand-powered jack most commonly seen in retail and personal warehousing operations. They are used predominantly for lifting, lowering and steering pallets from one place to another.\nPowered pallet jack.\nPowered pallet jacks, also known as electric pallet trucks, walkies, single or double pallet jacks, or power jack, are motorized to allow lifting and moving of heavier and stacked pallets. Some contain a platform for the user to stand while moving pallets. The powered pallet jack is generally moved by a throttle on the handle to move forward or in reverse and steered by swinging the handle in the intended direction. Some contain a type of dead man's switch rather than a brake to stop the machine should the user need to stop quickly or leave the machine while it is in use. Others use a system known as \"plugging\" wherein the driver turns the throttle from forward to reverse (or vice versa) to slow and stop the machine, as the dead man's switch is used in emergencies only.\nRough terrain pallet jack.\nRough terrain pallet jacks are designed specifically for use on uneven ground. They are made using heavy-duty frames and robust pneumatic tyres so that they can be manoeuvred over rough surfaces with ease. Many manufacturers opt for watertight wheel bearings, a hydraulic elevator or a built-in pump to ensure their rough terrain pallet jacks are easy and comfortable to use, even in the harshest conditions.\nOperational risks.\nPallet jacks are classed as material-handling equipment (MHE). Under most health and safety law, training is required in their use (particularly for powered pallet jacks) and, as the loads carried are heavy, there is a substantial risk of accidents resulting in injuries.\nTypical dimensions.\nIndustry seems to have 'standardized' pallet jacks in several ways:\nIn Eurasia the overall dimensions are similar, as modern container palletization has forced standardization in the dimensional domain globally.", "Engineering,_Manufacturing": 0.9999564886, "qwen": "Yes"}
{"id": "6403210", "revid": "1162514108", "url": "https://en.wikipedia.org/wiki?curid=6403210", "title": "Vapor polishing", "text": "Vapor polishing is a method of polishing plastics to reduce the surface roughness or improve clarity. Typically, a component is exposed to a chemical vapor causing the surface to flow thereby improving the surface finish. This method of polishing is frequently used to return clear materials to an optical quality finish after machining. Vapor polishing works well in the internal features of components.\nFeature size changes of the plastic component generally do not occur. Post stress relieving is usually required as vapor polishing sets up surface stresses that can cause crazing.\nPlastics that respond well to vapor polishing are polycarbonate, acrylic, polysulfone, PEI, and ABS.\nThe technique is also being used to improve the surface of objects created with 3D printing techniques. As the printer deposits layer upon layer of material to build the object, the surface is often not entirely smooth. The smoothness of the surface can be greatly increased by vapor polishing.", "Engineering,_Manufacturing": 0.999969244, "qwen": "Yes"}
{"id": "47757307", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=47757307", "title": "Rule based DFM analysis for deep drawing", "text": "Rule based DFM analysis for deep drawing. Deep drawing is a widely used cold sheet metal forming process to draw the sheet metal in forming dye of desirable cross-section using mechanical force of the punch. DFM refers to design for manufacturability. DFA refers to design for assembly. DFMA stands for design for manufacture and assembly. It is a practice for designing the engineering components keeping manufacturing and assembly aspects in mind. DFMA tries to tackle the problems that may come during the manufacturing and assembly at the design stage itself. Changes in the parts design to remove these problems while keeping the functionality of the parts intact. This is done to reduce the cost of iterations thus making the manufacturing of components more efficient and economical.\nIn the deep drawing process, a blank of sheet metal (usually circular) is placed on the die. The die is fixed to the base. The metal blank is held in position on the die using blank holder. Mechanical force is applied on the part of the metal blank above the die cavity through a punch. As the punch force increases the metal flows from the flange region in to the die cavity.\nHere is the Rule based DFM analysis for Deep drawing process. These rules can be incorporated at the design stage to improve the efficiency of the process:\nMaterial of Sheet Metal.\nAs the deep drawing is a cold forming operation, the germane properties of the sheet metal are formability, ductility and yield strength. The material should have good formability and ductility so that it can be drawn into the desired shape without any cracks. The yield strength of the material should be low facilitating initiation of the flow of metal without tearing near the punch radius.\nClearance between Punch and Die.\nClearance between the punch and die guides the flow of the metal into the die. Clearance should be more than the metal thickness to avoid concentration of metal at the top of the die cavity. Clearance should not be as large so that the flow of metal into the die region becomes unrestricted leading to the wrinkling of wall.\nDie corner radius.\nRadius of curvature at the die where the metal enters from the flange region into the die region is an important geometrical parameter. If the die corner radius is small than wrinkling near the flange region becomes more prominent. Too small die corner radius results in cracks due to sharp change in the direction of metal flow. Generally it should be 5-10 times the sheet thickness.\nPunch corner radius.\nAs the metal draws into the die the thickness of the sheet decreases near in the lower region of the punch. Maximum reduction happens near punch corner because the metal flow decreases significantly here. Too sharp corner results in cracks near the punch base. Corner radius of punch should be 4-10 times the sheet thickness.\nBlank holding force.\nThe friction in the flange region is mainly affected by blank holding force. Blank holding force is required for checking the amount of the metal flow in to the die. The low value of blank holding force results in wrinkling in the flange region and too high value of holding force results in increase in the drawing force due to the increase in the friction between the flange region. The blank holding force should be just enough to restrict the flow of the metal.\nDrawing Ratio.\nMeasurement of the amount of drawing performed on a sheet metal blank is quantified using drawing ratio. The higher the drawing ratio, the more extreme the amount of deep drawing. Due to the geometry, forces, metal flow and material properties of the work, there is a limit to the amount of deep drawing that can be performed on a sheet metal blank in a single operation. The drawing ratio is roughly calculated as,\nDR = Db/Dp.\nDb is the diameter of the blank and Dp is the diameter of the punch. For shapes that are noncircular the maximum diameter is sometimes used, or occasionally drawing ratio is calculated using surface areas. The limit to the drawing ratio for an operation is usually 2 or under", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "47772568", "revid": "40963171", "url": "https://en.wikipedia.org/wiki?curid=47772568", "title": "Rule based analysis of extrusion process", "text": "Extrusion is a plastic deformation process in which raw material (billet) is forced to flow by compression through the die opening of a smaller cross-section area. The extrusion process is divided in two basic types: direct extrusion and indirect extrusion. In direct extrusion the billet is pushed through the die with ram pressure, whereas in indirect extrusion a die moves relative to the container.\nRule based analysis of extrusion process would help to determine a set of rules essential for consideration while designing a product, or even during cost estimation of a product. Some rules are discussed below.\nMaterial.\nMaterial of the profile to be extruded plays an essential role in determining process parameters and potential limitations of a process. For example, minimum thickness of extruded carbon steel sheet is 3mm whereas same sheet of aluminium can be extruded into minimum sheet thicknesses of 1mm. A variety of materials such as Carbon steel, aluminium, titanium, magnesium, ABS and PVC etc. can be manufactured via extrusion processes.\nProfile shape.\nExtrusion processes can extrude sheets into a high variety of profile shapes, but it is essential to consider profile features, to ensure product feasibility and strength.\nWall thickness.\nWhen deciding the wall thickness of any extrusion profile, strength and cost efficiency are two main factors. Though Uniform wall thicknesses are most easy to manufacture, wall thickness can easily be varied as necessary within a profile. If changes in the wall thickness are unavoidable, make them as gradual rather than abrupt variations. Thick with thin cross sections should be avoided, as material tends to flow faster where thicker sections occur, giving rise to more expected distortion in an extruded shape.\nFor an extrusion process wall thickness may vary from 1mm (aluminium) to 32mm (PVC).\nCorner Radii.\nExtrusion processes cannot achieve sharp corners without additional fabrication. Internal corners should be filleted with a minimum radius of 0.5-1mm, and sharp external edges should be rounded as those tips can easily become wavy and uneven.\nSolid profiles if possible.\nSolid Profiles can reduce die costs and are often easier to produce.\nFewer cavities in hollow profiles.\nVarieties of hollow profiles are often very difficult to produce, but a hollow profile can be replaced by two telescoping profiles, to ease product manufacturing. In many cases reducing the number of cavities in a hollow profile makes it easier to extrude, which can also increases die stability.\nProfiles with deep channels.\nFor profiles with pockets or channels, a basic rule is that the width to height ratio should be approximately 1:3. This ensures that the strength of the die is not jeopardised. When using larger radii at the opening of the channel, and a full radius at the bottom, width-to-height ratios could rise to 1:4.\nHeat sinks.\nUse of cooling fins on profiles greatly increases areas for heat dissipation. Surface area can be further increased by giving any fins a wavy surface. An undulating surface increases heat dissipation area of any fins. However, where there is forced air-cooling longitudinally along the profile, it can be better to leave fins smooth. This helps to avoid a problem of eddy formation.\nSurface Finish.\nDuring an extrusion process it is essential to consider the surface finish of exposed product surfaces. As a general rule, the narrower an exposed surface, the more uniform its finish becomes. Webs, flanges and abrupt changes in metal thickness may show up as marks on the opposite surface of an extrusion, particularly on thin sections. The marking of exposed surfaces can be minimized with design changes such as rounding transitions, to reduce the chance of opposite-side streaking.\nSymmetry.\nSymmetry provides for more balance forces and helps avoiding over stressing areas of the extruding die. Hollow areas within the cross section, in particular, should be balanced.\nLength tolerances.\nSome waste tolerances are often included in a required extrusion's length. It can be difficult and expensive to cut a perfect length during production, as metals or thermoplastics expand and contract at different temperatures. Greater accuracy is often possible if lengths are cut off-line. A typical length tolerance for UPVC might be +/- 1mm (0.2%) on a 500mm total length.\nExtrusion ratio.\nExtrusion Reduction ratio is the ratio of the cross sectional areas in the shape of the die opening to that of the container through which the billet is pushed. A large-diameter billet pushed through a very small die opening has a high reduction ratio, and it may sometimes not be possible to extrude such a part. Ratios of 75:1 are common, though difficult.\nThe solution, however, for a difficult ratio shape is to make the part on a press with a smaller container. Another option is to use a multihole die that lets a number of profiles extrude simultaneously. They also come in handy for small shapes that are too long to handle practically, with even the shortest billets a press can extrude.", "Engineering,_Manufacturing": 0.9999997616, "qwen": "Yes"}
{"id": "47775245", "revid": "11308236", "url": "https://en.wikipedia.org/wiki?curid=47775245", "title": "DFM Guidelines for Hot Metal Extrusion Process", "text": "Extrusion is a metal forming process to form parts with constant cross-section along its length. This process uses a metal billet or ingot which is inserted in a chamber. One side of this contains a die to produce the desired cross section and the other side a hydraulic ram is present to push the metal billet or ingot. Metal flows around the profile of the die and after solidification takes the desired shape. \nExtrusion process can be done with the material hot or cold, but most of the metals are heated before the process, if high surface finish and tight tolerances are required then the material is not heated.\nDFM stands for design for manufacturing, so as the name suggest the design is manufacturing friendly, in simple terms design that can be manufactured easily and cheaply. DFM guidelines define a set of rules for a person designing a product to ease the manufacturing process, reduce cost and time. For example, if a hole is to be drilled, if the designer specifies a standard hole size then it reduces the cost because the drill bits of unusual sizes are not readily available they have to be custom made.\nMaterial based guidelines.\nNowadays, quite a wide variety of metals are currently extruded commercially, the most common are (in order of decreasing extrudability): Aluminium, Magnesium and their alloys, Copper and Copper alloys, low-carbon and medium-carbon steels, low-alloy steels and stainless steels. So obviously as the extrudability decrease the cost of production increases", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "47775741", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=47775741", "title": "Rule-based DFM analysis for electric discharge machining", "text": "Electrical discharge machining (or EDM) is one of the most accurate manufacturing processes available for creating complex or simple shapes and geometries within parts and assemblies. A machining method typically used for hard metals, EDM makes it possible to work with metals for which traditional machining techniques are ineffective.\nDesign for manufacturability (also sometimes known as design for manufacturing or DFM) is the general engineering art of designing products in such a way that they are easy to manufacture. The concept exists in almost all engineering disciplines, but the implementation differs widely depending on the manufacturing technology. DFM describes the process of designing or engineering a product in order to facilitate the manufacturing process in order to reduce its manufacturing costs. DFM will allow potential problems to be fixed in the design phase which is the least expensive place to address them. Other factors may affect the manufacturability such as the type of raw material, the form of the raw material, dimensional tolerances, and secondary processing such as finishing.\nDepending on various types of manufacturing processes there are set guidelines for DFM practices. These DFM guidelines help to precisely define various tolerances, rules and common manufacturing checks related to DFM. Rule based guidelines which can be referred to while designing parts are mentioned below. The parts are designed considering manufacturability with electrical discharge machining in mind.\nMechanical design considerations.\nMinimum internal corner radius.\nThe minimum internal corner radius of the feature will dictate the maximum wire diameter that can be used. The wire diameter needs to be less than double the minimum internal corner radius for successful machining. However, the amount of final overcut and a small amount of maneuvering need to be taken into account for the corner to be generated. For small diameter wires, the following are recommended:\nSurface finishing.\nSurface finishing comprises the small local deviations of a surface from the perfectly flat ideal. It is one of the important factors that controls friction and transfer layer formation during sliding.\nMany wire EDM machines have adopted the pulse generating circuit using low power for ignition and high power for machining. However, it is not suitable for finishing process since the energy generated by the high voltage sub-circuit is too high to obtain a desired fine surface. Relaxing the surface finish allows the manufacturer to produce the part with fewer passes, at a higher current level and a higher metal-removal rate, enabling lower production time and cost.\nMaterial removal.\nThe removal of material in EDM is associated with the erosive effects produced when discrete and spatial discharge occurs between the tool and work-piece electrodes. Short duration sparks generated between these two electrodes. The generator releases electrical energy, which is responsible for melting a small quantity of material from both the electrodes. The part should be designed and prepared such that the amount of stock removed by EDM is relatively small. Traditional machining techniques, such as milling can be used to remove bulk of stock with the finishing operations performed by EDM.\nSimultaneous machining.\nEDM enhanced with CNC systems is a highly competitive model for making forging dies, casting tooling, plastic injection molds and tooling for powder metals. It enables the user to machine simultaneously multiple highly precise parts from a single clamping. Designs should be considered such that several parts can be stacked and machined simultaneously or a single part can have several EDM operations performed simultaneously.\nEnlarging holes.\nWhen existing holes are to be enlarged or reshaped by EDM, through holes are preferred to blind holes as they permit easier flow of dielectric fluid past the area being machined.\nSharp corners.\nWhen cutting sharp corners, the wire dwells longer by the inside radius causing a slight overcut. On the outside radius, it speeds, leaving a slight undercut. Hence, sharp corners should be avoided while designing part.\nGalvanic corrosion.\nGalvanic corrosion is an electrochemical process in which one metal corrodes preferentially to another when both metals are in electrical contact, in the presence of an electrolyte. In EDM, there will be some degree of material exchange between the wire or the probe and the base material. Electrodes and base material should be chosen to prevent galvanic corrosion as far as possible.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "47780686", "revid": "36794807", "url": "https://en.wikipedia.org/wiki?curid=47780686", "title": "Rule based DFM analysis for metal spinning", "text": "Rule based DFM analysis for metal spinning. Metal spinning is a lesser known metal forming and fabricating manufacturing process. It is more conventionally used for the manufacturing of axis-symmetric parts. Its ability to create parts that require high tolerance and high strength makes it an outstanding process to manufacture a wide range of parts for automobile, aerospace, defence and medical industries. Typical components produced by metal spinning are lamp bases, reflectors, hollowware (pitchers, tankards, vases, candlesticks, etc.), pots, bans bowls and components for electrical equipment. Design for manufacturability (also sometimes known as design for manufacturing or DFM) is the general engineering art of designing products in such a way that they are easy to manufacture. The concept exists in almost all engineering disciplines, but the implementation differs widely depending on the manufacturing technology. DFM describes the process of designing or engineering a product in order to facilitate the manufacturing process in order to reduce the manufacturing costs. DFM will allow potential problems to be fixed in the design phase which is the least expensive place to address them. Other factors may affect the manufacturability such as the type of raw material, the form of the raw material, dimensional tolerances, and secondary processing such as finishing.\nDepending on various types of manufacturing processes that are set guidelines for Design for manufacturability (DFM) practices. These DFM guidelines help to precisely define various tolerances, rules and common manufacturing checks related to DFM. Below are certain rule based standard guidelines which can be referred to while designing parts for metal spinning considering manufacturability in mind.\nDesign Considerations.\nThe most common guidelines following design recommendations are not mandatory rules but rather suggestions for promoting ease of manufacture:\nMetal Thickness.\nThe thickness of the metal to be spun can vary from about 0.1 mm (0.004 in) to 120 mm (4 or 5 in) on special machines and with hot material. The most common thickness, however, are 0.6 to 1.3 mm (0.024 to 0.050 in). Maximum thickness and size are limited only by the size of the equipment and the power available to make the metal flow.\nSpecifying material 25 or 30 percent thicker than the finished-part thickness is usually sufficient to allow for such reduction in wall thickness. However, material too thick for easy spinning should not be specified. Both extra-thick and extra-thin materials make spinning more difficult. For precision work, extra thick metal pieces may be spun and then machined to final dimensions.\nShape.\nIn spinning, the conical shape is the easiest to form and the most economical. The metal is not subjected to such severe strain when worked down to its extreme depth because the angle at which the chuck meets the metal is small and allows better control of the metal during the spinning operation. The hemispherical shape is more difficult to spin because the angle grows increasingly sharper as the metal is forced farther back on the chuck. In spinning a cylinder, the metal is exposed to greater strain because of the sharp angle. This operation requires more time and skill.\nRadius at corners.\nBlended radii and fillets are preferable to sharp corners for ease of spinning. Sharp corners tend to cause thinning of stock and, in the case of external corners, breakage of wood or masonite chucks. A desirable minimum is 6 mm (1/4 in), although 3 mm (1/8 in) usually causes no problems. In the spinning process, a metal is exposed to larger strains at sharp angles.\nSpinning Ratio.\nSpinning ratio is defined as depth to diameter ratio and serves as a critical metric for the spinning process. A rating of 100 indicates maximum suitability for the type of spinning indicated, while lower rating values indicate proportionally less ease of forming with spinning methods. It is preferred to use as shallow part as possible, i.e. avoid deep cylindrical designs, which require repeated operations and annealing. A spinning ratio of less than 1:4 is preferable. Spinning ratios are normally classified as follows: Shallow (less than 1:4), Moderate (1:4 to 3:4), Deep(3:4 to 5:4).\nTapering Angle.\nIf the part has cylindrical sides and a wood chuck is used, allow a taper of 2° or more, if possible, to facilitate removal of the part from the chuck. With steel chucks, less taper is required, as little as 1/4° will be satisfactory.\nFeature Based Rules.\nInternal flanges and other configurations of re-entrant shapes are more costly to produce because they require special, more complex chucks or spinning without backup support for the work. Also, it is preferred to dimension parts to surfaces adjacent to the chuck (usually inside dimension). This allows the chuck maker to apply these dimensions directly to the chuck, and it avoids variations in diameter or length caused by variations in material thickness.", "Engineering,_Manufacturing": 1.0000059605, "qwen": "Yes"}
{"id": "47793176", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=47793176", "title": "Design of plastic components", "text": "Injection molding has been one of the most popular ways for fabricating plastic parts for a very long time. They are used in automotive interior parts, electronic housings, housewares, medical equipment, compact discs, and even doghouses. Below are certain rule based standard guidelines which can be referred to while designing parts for injection molding considering manufacturability in mind.\nGeometric considerations.\nThe most common guidelines refer to the specification of various relationships between geometric parameters which result in easier or better manufacturability. Some of these are as follows:\nWall Thickness.\nNon-uniform wall sections can contribute to warpage and stresses in molded parts. Sections which are too thin have a higher chance of breakage in handling, may restrict the flow of material and may trap air causing a defective part. Too heavy a wall thickness, on the other hand, will slow the curing cycle and add to material cost and increase cycle time.\nGenerally, thinner walls are more feasible with small parts rather than with large ones. The limiting factor in wall thinness is the tendency for the plastic material in thin walls to cool and solidify before the mold is filled. The shorter the material flow, the thinner the wall can be. Walls also should be as uniform in thickness as possible to avoid warpage from uneven shrinkage. When changes in wall thickness are unavoidable, the transition should be gradual and not abrupt.\nSome plastics are more sensitive to wall thickness than others, where acetal and ABS plastics max out at around 0.12 in. thick (3 mm), acrylic can go to 0.5 in. (12 mm), polyurethane to 0.75 in. (18 mm), and certain fiber-reinforced plastics to 1 in. (25 mm) or more. Even so, designers should recognize that very thick cross sections can increase the likelihood of cosmetic defects like sink.\nDraft angles.\nDraft angle design is an important factor when designing plastic parts. Because of shrinkage of plastic material, injection molded parts have a tendency to shrink onto a core. This creates higher contact pressure on the core surface and increases friction between the core and the part, thus making ejection of the part from the mold difficult. Hence, draft angles should be designed properly to assist in part ejection. This also reduces cycle time and improves productivity. Draft angles should be used on interior and exterior walls of the part along the pulling direction. \nThe minimum allowable draft angle is harder to quantify. Plastic material suppliers and molders are the authority on what is the lowest acceptable draft. In most instances, 1degree per side will be sufficient, but between 2 degree and 5 degree per side would be preferable. If the design is not compatible with 1 degree, then allow for 0.5 degree on each side. Even a small draft angle, such as 0.25 degree, is preferable to none at all.\nRadius at corners.\nGenerously rounded corners provide a number of advantages. There is less stress concentration on the part and on the tool. Because of sharp corners, material flow is not smooth and tends to be difficult to fill, reduces tooling strength and causes stress concentration. Parts with radii and fillets are more economical and easier to produce, reduce chipping, simplify mold construction and add strength to molded part with good appearance.\nSharp Corners general design guidelines in injection molding suggest that corner radii should be at least one-half the wall thickness. It is recommended to avoid sharp corners and use generous fillets and radii whenever required. During injection molding, the molten plastic has to navigate turns or corners. Rounded corners will ease plastic flow, so engineers should generously radius the corners of all parts. In contrast, sharp inside corners result in molded-in stress particularly during the cooling process when the top of the part tries to shrink and the material pulls against the corners. Moreover, the first rule of plastic design i.e. uniform wall thickness will be obeyed. As the plastic goes around a well-proportioned corner, it will not be subjected to area increases and abrupt changes in direction. Cavity packing pressure stays consistent. This leads to a strong, dimensionally stable corner that will resist post-mold warpage.\nHole depth to diameter ratio.\nCore pins are used to produce holes in plastic parts. Through holes are easier to produce than blind holes which don't go through the entire part. Blind holes are created by pins that are supported at only one end; hence such pins should not be long. Longer pins will deflect more and be pushed by the pressure of the molten plastic material during molding. It is recommended that hole depth-to-diameter ratio should not be more than 2.\nFeature Based Rules.\nRibs.\nRib features help in strengthening the molded part without adding to wall thickness. In some cases, they can also act as decorative features. Ribs also provide alignment in mating parts or provide stopping surfaces for assemblies. However, projections like ribs can create cavity filling, venting, and ejection problems. These problems become more troublesome for taller ribs. Ribs need to be designed in correct proportion to avoid defects such as short shots and provide the required strength. Thick and deep ribs can cause sink marks and filling problems respectively. Deep ribs can also lead to ejection problems. If ribs are too long or too wide, supporting ribs may be required. It is better to use a number of smaller ribs instead of one large rib.\nBoss.\nBoss, a basic design element in plastics, is typically cylindrical and used as a mounting fixture, location point, reinforcement feature or spacer. Under service conditions, bosses are often subjected to loadings not encountered in other sections of a component. \nUndercut detection.\nUndercuts should be avoided for ease of manufacturing. Undercuts typically require additional mechanisms for manufacture adding to mold cost and complexity. In addition, the part must have room to flex and deform. Clever part design or minor design concessions often can eliminate complex mechanisms for undercuts. Undercuts may require additional time for unloading molds. It is recommended that undercuts on a part should be avoided to the extent possible.\nFillet.\nSharp corners increase concentrations, which are prone to air entrapments, air voids, and sink marks hence weakening the structural integrity of the plastic part. It must be eliminated using radii whenever is possible.\nIt is recommended that an inside radius be a minimum of one times the thickness.\nAt corners, the suggested inside radius is 0.5 times the material thickness and the outside radius is 1.5 times the material thickness. A bigger radius should be used if part design allows\nSimulation.\nThe design of injection moulded components can be further improved and optimised by using injection moulding simulation software such as Autodesk Moldflow and SolidWorks Plastics. This software works with components designed in CAD to simulate how a polymer behaves when it enters a injection mould cavity. It can predict how the molten material flows and freezes, any part geometry that is too thin or too thick and if there are any weaknesses created in the plastic from defects such as weld lines.\nWhen simulation is undertaken in the design phase of a project, in advance of the tool being manufactured, it can help to identify the problems discussed above and allow the designer to iteratively modify and re-simulate the design to make improvements. Use of simulation in the design phase can help to reduce problems with the physical mould and therefore reduce time to market, reduce the use of material and energy, prevent surface defects such as sink and flow marks, and reduce the time taken to inject, cool and eject the part, improving the injection moulding machine's output rate.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "14755952", "revid": "16944068", "url": "https://en.wikipedia.org/wiki?curid=14755952", "title": "Machine Sazi Tabriz", "text": "Machine Sazi Tabriz Co. (Tabriz Machinery Manufacturing Co.) which is also called by its abbreviation MST, is a Machine tool manufacturing factory in Tabriz, Iran. The major products of the factory are machinery tools such as turning machines, milling machines, drilling machines, grinding machines. A large variety of MST's products are CNC controlled machines. The MST manufacturing complex established on 1969 with technological helps from east European countries. The MST serves as a nationwide base for design and manufacturing of machine tools. MST owns the Machine Sazi football club, since 1969 to now.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "31538825", "revid": "32990417", "url": "https://en.wikipedia.org/wiki?curid=31538825", "title": "Shelf-ready packaging", "text": "Shelf-ready packaging (SRP) and retail-ready packaging (RRP) (also \"prêt-à-vendre\" (PAV)) refers to the packaging of a product so that it is delivered to a retailer in packaging which is optimized for efficient stocking and sale. \nBackground.\nRetailers, particularly large big-box stores, superstores and warehouse clubs, sell large quantities of fast-moving consumer goods. These retailers often want to have items shipped from their distribution centers to the stores in unit loads and bulk boxes: these can be stocked without handling of the merchandise. The purpose of corrugated shipping containers is to put case goods directly onto shelves and stocking locations without individually handling the unit packs or primary packages. Many large retailers ask for items to remain on pallets rather than use shelves. Retailers often require products to come in retail-ready packaging to reduce stocking costs by saving labor expenses.\nReady-to-go display stands and end caps are put in the retail sales location by forklift trucks without assembly or manual handling of unit packs.\nRequirements.\nRetailers commonly specify all aspects of incoming logistics and packaging to their suppliers. This includes pallet size, bar code format and placement, RFID tags, strength of corrugated shipping containers etc. Boxes must be easy to open and prepare for stocking. Several designs are available. Box perforations, tear tape, etc. must be intuitive and easy. box cutters are often discouraged. Frequently, requirements for reusable packaging and sustainable packaging are also provided.\nThe principles of shelf-ready packaging are almost universal. Not all retailers have identical requirements. For example, Costcos \"Structural Packaging Specifications\", Target's \"Shelf Ready and Transit Packaging Standards, Hardgoods\", and Walmart's \"RRP and PDQ Display Standard Style Guide\" are similar but not identical.\nRegional coordination in Europe has produced an agreement on common functional requirements for the design of SRP. The Efficient Consumer Response (ECR), Europe Working Group, has published \"Shelf Ready Packaging\" to help standardize programs.\nManufacturers and packagers need to be aware of the diverse requirements of retailers as they package and ship products. Sometimes consultants and contract packagers with experience in shelf-ready-packaging are useful.\nTypes.\nDue to the fact that there are many different products which need to be packed in a SRP, products can be delivered by a variety of solutions.\nShelf tray.\nSRP solutions which can be placed in the shelf are predominantly made of corrugated cardboard. In general, these consist of a tray (secondary packaging) and a cover (a lid which protects the product). The cover can be easily separated from the tray by a perforation. Sometimes the cover of a tray is a transparent film which protects the products from mechanical and climatic influences.\nRe-usable plastic tray.\nIn addition to SRP made of corrugated cardboard, packaging can also be made of reusable materials such as plastic. Such plastic containers can be reused directly in the store. If reuse is not possible, the containers can be returned to the producer.\nMerchandising unit.\nMerchandising units represent another type of SRP solutions. They are used for secondary placement. Normally, promotional goods or fast-moving products are presented in a merchandising unit. An enormous number of products can be placed in a merchandising unit. Therefore, the merchandising unit serves as SRP. Secondary placements can trigger impulse purchases. Often, roll-up palettes, called dollies, are used as a base for merchandising units. Rolling pallets facilitate the handling of merchandising units and increase flexibility.\nImportance of shelf-ready packaging.\nShelf-ready packaging continues to be growing in many market segments, including over-the-counter pharmaceuticals. SRP helps retail stores to achieve cost savings in labor and in packaging materials. It also makes packaged products easier to spot for customers, resulting in better sales. Significant efforts and investments are usually made in improving aisle efficiency for consumers, ensuring consistent demand for suitable retail-ready products from physical outlets.", "Engineering,_Manufacturing": 0.9975638986, "qwen": "Yes"}
{"id": "65279010", "revid": "19404073", "url": "https://en.wikipedia.org/wiki?curid=65279010", "title": "Fast Radius", "text": "Fast Radius  is a company that provides manufacturing services in four main areas: application discovery, product design and testing, production-grade manufacturing, and global fulfillment. Its on-demand manufacturing capabilities include additive manufacturing, or 3D printing, CNC machining, injection molding, and urethane casting.\nFast Radius’ headquarters is located in Chicago, Illinois, with additional facilities located in Atlanta, Georgia; Louisville, Kentucky; and Singapore. Fast Radius operates a digital Cloud Manufacturing Platform that allows users to order parts and manage the product lifecycle from product development through fulfillment.\nHistory and about.\nFast Radius, LLC was formed in 2014 by Rick Smith and Mitch Free, and in 2017, Fast Radius, LLC merged with Fast Radius, Inc. Fast Radius, Inc. was co-founded by Lou Rassey, Pat McCusker, Bill King, and John Nanry in a partnership with the shipping and logistics company UPS in an effort to leverage additive manufacturing as a supply chain solution. Since its founding, the company has grown to more than 240 full-time employees and has expanded from supply chain solutions to all manner of parts manufacturing.\nCurrently, Fast Radius specializes in manufacturing industrial-grade metal and plastic parts for applications including consumer goods, medical devices, automotive, aerospace, industrial equipment, and electronics, along with product development and design services and artificial phalluses.\nIts Chicago headquarters, which has been in operation since 2018, is home to the largest public install base of Carbon DLS 3D printers in North America. It was named a Lighthouse Factory, a distinction honoring the best digital factories in the world, by the World Economic Forum.\nIn addition, Fast Radius’ has a large footprint of HP Multi Jet Fusion (MJF) equipment, Formlabs Stereolithography (SLA) printers, and the Desktop Metal Studio System. Fast Radius also has a robust presence of Stratasys FDM printers co-located at the UPS World Port facility in Louisville, Kentucky. The company is technology-agnostic, and works with a global network of manufacturers to provide CNC machining, injection molding, and urethane casting services.\nNotable customers include Satair (an Airbus Services Company), Curtiss Motorcycles, Axial3D, Bastian Solutions (a Toyota Advanced Logistics Company), Rawlings, Yanfeng, Aptiv, Danfoss, and Steelcase.\nIn 2019, Fast Radius raised $48 million in a Series B funding round led by UPS and assisted by Drive Capital.\nDuring the COVID-19 pandemic, Fast Radius designed a 3D-printed respirator mask in response to the nationwide PPE shortage. The company released the design files and instructions online as an open-source resource. Fast Radius also produced face shield kits for frontline healthcare workers. They also worked with the University of Illinois at Urbana-Champaign to design and patent a microfluidics chip for a point-of-care COVID-19 testing solution.\nIn 2022, the company became listed on Nasdaq through a merger with ECP Environmental Growth Opportunities Corp. As of August 29, 2022, the company remains insolvent and the stock's share price is down over 95% since its IPO.", "Engineering,_Manufacturing": 0.9996936321, "qwen": "Yes"}
{"id": "19514697", "revid": "43417927", "url": "https://en.wikipedia.org/wiki?curid=19514697", "title": "Race (bearing)", "text": "The rolling-elements of a rolling-element bearing ride on races. The large race that goes into a bore is called the \"outer race\", and the small race that the shaft rides in is called the \"inner race\".\nDesign.\nIn the case of ball bearings, the bearing has inner and outer \"races\" and a set of balls. Each race is a ring with a groove where the balls rest. The groove is usually shaped so the ball is a slightly loose fit in the groove. Thus, in principle, the ball contacts each race at a single point. However, a load on an infinitely small point would cause infinitely high contact pressure. In practice, the ball deforms (flattens) slightly where it contacts each race, much as a tire flattens where it touches the road. The race also dents slightly where each ball presses on it. Thus, the contact between ball and race is of finite size and has finite pressure. The deformed ball and race do not roll entirely smoothly because different parts of the ball are moving at different speeds as it rolls. Thus, there are opposing forces and sliding motions at each ball/race contact. Overall, these cause bearing drag. \"V\" groove raceways distribute the load evenly over the balls as they travel on four points of contact, creating a straight line rolling effect and decreasing the amount of friction created by a full contact round groove design.\nIn some applications the two races may be arranged on plates parallel to the plane of the balls, rather than on inner and outer sleeves. In this case, the inner and outer sides of the grooves that form the race should have different angles with respect to this plane, with a steeper angle on the inside groove and a shallower angle on the outside groove, so that each ball can rotate properly without slipping.\nManufacture.\nCenterless grinding.\nThe outer diameter (OD) of the races are often centerless ground using the throughfeed process. Centerless grinding can achieve a very high degree of accuracy, especially when done in stages. These stages are: rough, semi-finish and finish. Each grinding stage is designed to remove enough stock material from the casing so that the next stage does not encounter any problems such as burning or surface chatter, the finish stage achieves the final dimension. Each grinding wheel at all of the aforementioned stages has a varying degree of abrasive quality (finish being the finest grade) to achieve the appropriate stock removal for the next stage and final surface finish required.\nFeeding.\nBearing casings are introduced to the grinding action via means of a transfer from the delivery system to a pair of infeed rollers, these infeed rollers are tapered to a certain angle so that the casings are driven forward until the regulating wheel and grinding wheel catch them and slow them to their grinding speed which can be altered by speed control of the regulating wheel. The casings are constantly rotating and are fed into the grinding area to prevent separation which can cause finish/size problems or even a \"bump\" that can potentially crack or destroy casings and will damage the grinding and regulating wheels.\nWork rest blade.\nWhilst grinding, the bearing cases run through the grinding stages in one long tube of casings that is showered with a cutting fluid.\nThe 'tube' rests on a hardened steel blade with an angled, highly ground surface held on a horizontal plane between the grinding wheel and regulating wheel, often named a Work Rest Blade, the tube causes wear on the working surface of the blade so it must be reground at regular intervals. The height of the work rest blade perfectly aligns the bearing casing with the horizontal centreline of the grinding wheel creating a flawless ground finish, the work rest blade height can be altered using packing bars placed underneath the blade, height adjustments must be made depending on the diameter of the casings being ground.\nInspection.\nEach casing exits the grinding zone onto a high speed conveyor that delivers them to whatever storage and/or inspection arrangement a manufacturer may have, inspection is also carried out by the operator of the centreless line, by checking finish appearance, diameter, squareness and roundness by use of a dial test indicator in varying configurations, size allowances are permitted but are extremely tight depending on the customers requirements and can vary plus or minus within micrometres of finish diameter, Sizes can be adjusted on all grinding stages via a compensation button which can be pushed to remove extra material in varying micrometre units, the grinding wheel can move away at the same compensation to make the casings bigger if so required if the casing size moves from the operators target, and as the grinding wheel wears. Because a centerless grinding line has typically three grinding machines the operator must be in complete control and must prevent blockages in transfers, grinding exits and packing areas, also size and quality must constantly be checked, so the operator is always alert while operating the line and checking for problems and quality issues.\nSafety.\nSafety features include an emergency stop button which immediately moves the grinding wheel away from the ground rings on its revolutionary axis. Because of the wheel's momentum, it cannot be stopped but the power is cut and the wheel slows naturally, it cannot be reactivated until the emergency stop is reset. After the emergency stop is activated, the size of the workpiece must be re-established before the line can be reactivated into production mode.\nFinishing.\nThe outer and inner bearing casings are then sent on for raceway grinding, superfinishing and final assembly.", "Engineering,_Manufacturing": 0.9998986721, "qwen": "Yes"}
{"id": "19519695", "revid": "1639942", "url": "https://en.wikipedia.org/wiki?curid=19519695", "title": "Board-to-board connector", "text": "Board-to-board (BTB) connectors are used to connect printed circuit boards (PCB), electronic components that contain a conductive pattern printed on the surface of the insulating base in an accurate and repeatable manner. Each terminal on a BTB connector is connected to a PCB.\nA BTB connector includes housing and a specific number of terminals. The terminal is made from a conductive material (mostly copper alloy), and plated to improve conductivity and antirust. Terminals transmit the current/signal between PCBs connected by BTB; the housing is made of insulating material (mostly plastic).\nClassification.\nBTB connectors are divided up into four mounting types:\nBTB connectors are selected by considering the mounting method, pin pitch, number of the rows (aka number of the ways), pin length, stacker height etc.", "Engineering,_Manufacturing": 0.9999302626, "qwen": "Yes"}
{"id": "51576527", "revid": "1893804", "url": "https://en.wikipedia.org/wiki?curid=51576527", "title": "Design for inspection", "text": "Design for inspection (DFI) is an engineering principle that proposes that inspection methods and measurement instruments used to certify manufacturing conformity, should be considered early in the design of products. Production processes should be designed in such a way that features of the product are easy to inspect with readily available measurement instruments, and so that measurement uncertainty is considered in the tolerance that are applied. The concept can be applied in almost all engineering disciplines. DFI describes the process of designing or engineering a product in order to facilitate the measurement in order to reduce the overall costs of manufacturing and delivering products that satisfy customers.\nThe role of inspection in the manufacturing process is to ensure that the manufacturing process is producing components that meet the specification requirements. Inspection does not assure the quality of the product, only a robust and repeatable manufacturing process can achieve this. Therefore, inspection is often considered as an overhead although an extremely important one. Similar to design for manufacture (DFM) and design for assembly (DFA) (which seek to avoid designs which are difficult to make), the concept of DFI considers measurement capabilities at an early stage in the product development life cycle and uses knowledge of the fundamental principles of metrology to achieve cost reduction. If the inspection method and instruments are considered and selected at the design stage, the likelihood that a tolerance feature cannot be inspected or requires a specialised instrument is substantially reduced. High precision features require specialised manufacturing and metrology, these can have limited availability in the supply chain and therefore often have increased cost. The concept of DFI should complement and work in collaboration with DFM and DFA. There are three key areas when considering DFI, datum selection, tolerances and accessibility, plus general metrology considerations. Getting the most from inspection techniques will help improve quality. It is still difficult for systems designers to build machines that allow finished products to be inspected easily. To do so requires an understanding of the product being manufactured and how inspection tasks can improve the quality control process.\nInspection can represent a significant percentage of an existing product's manufacturing cost. DFI may naturally be called for in redesign of a product to reduce that cost component when it is high. However, DFI will not always reduce inspection costs: it can also lead to increased rate of inspection, because more convenient or higher quality measurement may justify increasing measurements, say from a sampling rate satisfactory to support a basic level of tolerance to a higher rate (e.g. to 100%). Or DFI may make it economical for 100% inspections to measure more features or to make repeated measures of the same feature at different points within the manufacturing process. This would be justified if it would reduce internal failure costs (such as costs of rework or scrap) or external failure costs (such as customer returns) within the cost of quality framework.\nReferences.\nhttps://www.designnews.com/document.asp?doc_id=224661 is out of date", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "26407130", "revid": "1660229", "url": "https://en.wikipedia.org/wiki?curid=26407130", "title": "OptiY", "text": "OptiY is a design environment software that provides modern optimization strategies and state of the art probabilistic algorithms for uncertainty, reliability, robustness, sensitivity analysis, data-mining and meta-modeling.\nFeatures.\nOptiY is an open-source, multidisciplinary design environment, which provides direct and generic interfaces to many CAD/CAE-systems and house-intern codes. Furthermore, a complex COM-interface and a user-node with predefined template are available so that user can self-integrate extern programs for ease of use. The insertion of any system to an arbitrary process chain is very easy using the graphical workflow editor. Collaborating different simulation model classes is possible as networks, finite-element-method, multi-body-system, material test bench etc.\nData mining.\nData mining is the process of extracting hidden patterns from data. Data mining identifies trends within data that go beyond simple data analysis. Through the use of sophisticated algorithms, non-statistician users have the opportunity to identify key attributes of processes and target opportunities. Data mining is becoming an increasingly important tool to transform this data into information. It is commonly used in a wide range of applications such as manufacturing, marketing, fraud detection and scientific discovery etc.\nSensitivity analysis.\nLocal Sensitivity as correlation coefficients and partial derivatives can only used, if the correlation between input and output is linear. If the correlation is nonlinear, the global sensitivity analysis has to be used based on the variance-relationship between input- and output-distribution as Sobol index. With sensitivity analysis, the system complexity can be reduced and the cause-and-effect chain can be explained.\nProbabilistic simulation.\nThe variability, uncertainty, tolerance and error of the technical systems play an important part by the product design process. These cause by manufacturing inaccuracy, process uncertainty, environment influences, abrasion and human factors etc. They are characterized by a stochastic distribution. The deterministic simulation cannot predict the real system behaviors due to the input variability and uncertainty, because one model calculation shows only one point in the design space. Probabilistic simulation has to be performed. Thereby, the output distributions will be calculated from input distributions based on the deterministic simulation model by any simulation system. The realistic system behaviors can be derivate from these output distributions.\nReliability analysis.\nThe variability of parameters causes often a failure of the system. Reliability analysis (Failure mode and effects analysis) investigates the boundary violation of output due to input variability. The failure mechanisms of components are known in the specification for the product development. They are identified by measurement, field data collection, material data, customer-specifications etc. In the simulation, the satisfaction of all product specifications is defined as constraints of the simulation results. The system reliability is given, if all constraints scatter insight the defined boundaries. Although a nominal parameter simulation shows that all values of the constraints are located in reliable boundaries, the system reliability however cannot be warranted due to input variability. A part of the constraints variability, which violates the defined boundaries, is called the failure probability of the solution. Reliability analysis computes the failure probability of the single components and also of the total system at a given time point.\nMeta-modeling.\nMeta-modeling or Surrogate model is a process to win the mathematical relationship between design parameters and product characteristics. For each point in the parameter space, there is a corresponding point of the design space. Many model calculations should be performed to show the relationship between input and output systematically (Full Factorial Design). For a high computing effort of the product model, it is practically infeasible. Adaptive response surface methodology can be used to solve this problem.\nFatigue life prediction.\nPredicting fatigue (material) has been one of the most important problems in design engineering for reliability and quality. They have several practical uses: rapid design optimization during development phase of a product and predicting field use limits as well as failure analysis of product returned from the field or failed in qualification test. Fatigue analysis focus on the thermal and mechanical failure mechanism. Most fatigue failure can be attributed to thermo-mechanical stresses caused by differences in the coefficient of thermal and mechanical expansion. The fatigue failures will occur when the component experiences cyclic stresses and strains that produce permanent damage.\nMulti-objective optimization.\nIn development process of technical products, there are frequently design problems with many evaluation goals or criteria as low cost, high quality, low noise etc. Design parameters have to be found to minimize all criteria. In contrast to a single optimization, there is another order structure between parameter and criteria spaces at a multi-objective Optimization. Criteria conflict each other. Trying to minimize a criterion, other criteria may be maximized. There is not only one solution, but also a Pareto optimal solution frontier. Multi-objective optimization finds all Pareto solutions automatically with a single run. The multiple decision making support tool is also available to select one best suitable solution from them.\nRobust design optimization.\nVariability, uncertainty and tolerance have to be considered for design process of technical systems to assure the highly required quality and reliability. They are uncontrollable, unpredictable and cause the uncertainty satisfaction of the required product specifications. The design goal is assuring of the specified product functionalities in spite of unavoidable variability and uncertainty. The approach solving this problem is robust design of the product parameters in the early design process (Robust Parameter Design (RPD)). Thereby, optimal product parameters should be found. Within, the system behavior is robust and insensitive in spite of unavoidable variability. E.g. the consistent variability and uncertainty leads only to the smallest variability of the product characteristics. So, the required product specifications will be always satisfied.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "26422563", "revid": "23914831", "url": "https://en.wikipedia.org/wiki?curid=26422563", "title": "Wafer backgrinding", "text": "Wafer backgrinding is a semiconductor device fabrication step during which wafer thickness is reduced to allow stacking and high-density packaging of integrated circuits (IC).\nICs are produced on semiconductor wafers that undergo a multitude of processing steps. The silicon wafers predominantly used today have diameters of 200 and 300 mm. They are roughly 750 μm thick to ensure a minimum of mechanical stability and to avoid warping during high-temperature processing steps.\nSmartcards, USB memory sticks, smartphones, handheld music players, and other ultra-compact electronic products would not be feasible in their present form without minimizing the size of their various components along all dimensions. The backside of the wafers are thus ground prior to wafer dicing (separation of the individual microchips). Wafers thinned down to 75 to 50 μm are common today.\nPrior to grinding, wafers are commonly laminated with UV-curable back-grinding tape, which ensures against wafer surface damage during back-grinding and prevents wafer surface contamination caused by infiltration of grinding fluid and/or debris. The wafers are also washed with deionized water throughout the process, which helps prevent contamination.\nThe process is also known as \"backlap\", \"backfinish\" or \"wafer thinning\".", "Engineering,_Manufacturing": 0.9999930859, "qwen": "Yes"}
{"id": "26429370", "revid": "1130364437", "url": "https://en.wikipedia.org/wiki?curid=26429370", "title": "Interchim", "text": "Interchim is a privately owned French company specialized in manufacturing and distribution of reagents, consumables and dedicated instruments for the R&D and industry laboratory in the fields of fine chemistry, chromatography and bio-analysis. It has become a provider of reference methods, products for analytics (analytical chemistry and bioassays) serving research and quality control in the biomedical field, pharmaceutical industry, but also cosmetics and environment.\nHistory.\nInterchim was founded by Boch Jean (formerly chemical engineer at Rhone-Poulenc) and Boch Colette in 1970. Their initial activity started with distribution of fine chemicals, then chromatography and Biology. Production was developed as well, in each fields. Affiliate companies were created for production and commercial activities in France, UK (2003), USA (2007) and Instrumentation business (2010). Interchim has now major activity in fine chromatography, fine chemistry and bio-analysis. Leadership in analytical sciences is based on distribution from leading groups (Agilent, Perkin Elmer, Jackson Immunoresearch, Novus, Radleys...), collaborations and proprietary innovative products.\nReferences.\nInterchim (headquarters) web site", "Engineering,_Manufacturing": 0.9982937574, "qwen": "Yes"}
{"id": "26431152", "revid": "37102400", "url": "https://en.wikipedia.org/wiki?curid=26431152", "title": "Belairbus", "text": "Belairbus is a Belgian aerospace manufacturer. It is a consortium established to allow a number of Belgian companies to participate in the manufacturing of Airbus aircraft while fulfilling Airbus' stipulation that it only deal with one entity in each European country that wants to be a part of the Airbus manufacturing program. It is an associated partner of Airbus, manufacturing parts for the Airbus A320 family, the Airbus A340 and the Airbus A380.\nHistory.\nBelairbus was formed in 1979 as a consortium of the Belgian government; the development authority of Wallonia; and the companies SONACA (formerly Avions Fairey), Fabrique Nationale and Asco. The consortium was established to participate in manufacturing the Airbus A310, being responsible for A310 wing leading edge slats, slat tracks and Krueger flaps. Airbus called Belairbus an \"associate\", along with Fokker, as both companies were involved with manufacturing Airbus aircraft without being shareholders in Airbus.\nThe consortium partners are now Sonaca, Asco Industries and Eurair, a subsidiary of Watteeuw Group. Belairbus subcontracts manufacturing to these three consortium members. Each consortium member's share in Belairbus is in proportion to the value of its production for the consortium; Sonaca's share is approximately 58%, Asco's 35%, and Eurair's 7%, with a single share also held by Belgian aerospace company SABCA.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "56507", "revid": "43351275", "url": "https://en.wikipedia.org/wiki?curid=56507", "title": "Marlinespike hitch", "text": "The marlinespike hitch is a temporary knot used to attach a rod to a rope in order to form a handle. This allows more tension than could be produced comfortably by gripping the rope with the hands alone. It is useful when tightening knots and for other purposes in ropework. \nAs the name suggests, the type of rod traditionally used with this hitch is a marlinespike. The advantages of this hitch over others which might serve the purpose are its quickness of tying and ease of releasing. Topologically it is a form of the noose, but in practice this hitch is not allowed to collapse into that shape. When it does capsize into a traditional noose, it can jam against the rod, making it much more difficult to release.\nThe hitch is frequently used by hammock campers to attach adjustable rope slings (\"whoopie slings\") to the webbing straps that are used to attach hammocks to trees.\nBy passing the working end through the marlinespike hitch, this knot can be used as an alternative method of tying the Bowline knot. Passing through in the opposite direction will give you the Cowboy bowline (also known as the left-hand bowline, Dutch marine bowline or winter bowline).\nTying.\nBelow is a basic method of tying. The knot can also be made by using the rod itself to form the loop, but the tying method does not affect the performance of the resulting hitch.\nBegin with an overhand loop, that is, a loop in which the working part passes over the standing part:\nFold the loop over the working part, towards the standing part such that the standing part is visible through the center of the loop:\n\nIn stiffer material the first two steps can be accomplished in a single motion by twisting the working part with the fingers until a loop forms and flops over the standing part.\nUse the rod to snag a bight of the standing part through the loop, that is, pass the rod over the near side of the loop, under the standing part and then over the far side of the loop:\nBefore tensioning, excess slack can be removed by pulling \"simultaneously\" on both the working and standing parts:\n\nIn actual use the hitch should be loaded only from the standing side.\nUndesirable capsized form.\nIf the working end is loaded rather than the standing part, the knot will capsize into an overhand noose:\n\nWhile this form may still hold when the standing part is subsequently loaded, it can jam badly against the rod. This is especially troublesome if the rod is not tapered.", "Engineering,_Manufacturing": 0.9993928671, "qwen": "Yes"}
{"id": "23564471", "revid": "21112944", "url": "https://en.wikipedia.org/wiki?curid=23564471", "title": "Line management", "text": "Line management refers to the management of employees who are directly involved in the production or delivery of products, goods and/or services. As the interface between an organisation and its front-line workforce, line management represents the lowest level of management within an organisational hierarchy (as distinct from top/executive/senior management and middle management).\nA line manager is an employee who directly manages other employees and day-to-day operations while reporting to a higher-ranking manager. In some retail businesses, they may have titles such as head cashiers or department supervisor. Related job titles are supervisor, section leader, foreperson, office manager and team leader. They are charged with directing employees and controlling that the corporate objectives in a specific functional area or line of business are met.\nDespite the name, line managers are usually considered as part of the organization's workforce and not part of its management class.\nResponsibilities.\nLine managers are responsible for implementing and enabling, through their staff, an organisation's people policies and practices in alignment with business objectives and core values. \nTheir main functions with respect to employees include: \nLine managers' activities typically include: \nLine management is also responsible for adopting (with the support of senior management) any type of organizational culture change.\nThe line management function will often cross into other functions vital to the success of a business such as human resources, finance, and risk management. Indeed, at corporations, responsibility for risk management is vested with line management. Human resources obligations are also increasingly being assigned or \"devolved\" to line managers.", "Engineering,_Manufacturing": 0.9921168089, "qwen": "Yes"}
{"id": "23572891", "revid": "30607451", "url": "https://en.wikipedia.org/wiki?curid=23572891", "title": "Computer-aided inspection", "text": "Computer-aided inspection (CAI) is the use of software tools to assess manufactured objects. It is closely related to computer-aided design (CAD) and computer-aided manufacturing (CAM). Its primary purpose is to allow engineers to more quickly and precisely assess the physical properties of manufactured objects. These properties can include dimensions, material consistency, roughness and roundness.\nUses.\nCAI has applications in industries ranging from food production to aerospace, commonly being used in the quality assurance step of the manufacturing process. It involves comparing manufactured objects with a CAD model, technical drawing or data sheet to ensure that the finished product is within specification and meets design intent.\nTechnologies.\nCAI machines can use a variety of technologies depending on the material of the product to be inspected, the properties to be measured, and the precision required.\nDigital Cameras.\nDigital cameras are frequently used in situations where the shape or colour of an object needs to be analysed. Using machine vision, the CAI program can make decisions about objects by comparing them to a master photo or data array.\nLaser Scanning.\nLaser scanning CAI machines use point clouds to generate a 3D model which is compared to the required specification. Laser scanners are generally used to check the external geometry of parts with low reflectivity and translucence.\nStructured Light Scanning.\nStructured light scanners use projected light patterns and digital cameras to analyse the geometry of an object. As with laser scanning, objects with high reflectivity and translucence can cause problems but temporary coatings can be applied to prevent this.\nCT Scanning.\nIndustrial CT scanners use X-rays to image an object from many angles, building up a 3D image to compare to a specification. CT scans can be used to analyse the internal geometry of parts because the X-rays penetrate the object being scanned. Higher resolution CT scans can also check for cavities, cracks, and other undesirable features inside parts.", "Engineering,_Manufacturing": 1.00000453, "qwen": "Yes"}
{"id": "23585809", "revid": "35354423", "url": "https://en.wikipedia.org/wiki?curid=23585809", "title": "Dana 44", "text": "The Dana 44 is an automotive axle manufactured by Dana Holding Corporation and is used among automobile manufacturers and in the automotive aftermarket area as well.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "9530717", "revid": "27324044", "url": "https://en.wikipedia.org/wiki?curid=9530717", "title": "Lambert (automobile)", "text": "The Lambert Automobile Company was a United States automobile manufacturing company which produced the Lambert automobile from 1905 to 1916. The company was founded by automotive pioneer John William Lambert and was based in Anderson, Indiana. \nIn 1891, John Lambert successfully tested and drove a three-wheeled, surrey topped, gasoline powered runabout of his own design. Despite the success of the car, the vehicle was a marketing failure. Priced at $550, not a single party was interested. Undaunted, Lambert turned his attention to the manufacture of stationary gasoline engines. He selected Anderson, Indiana as the site for his Buckeye Manufacturing Company. During this time he developed the friction transmission that would be a feature on all of his cars. He made an unsuccessful attempt to buy out a model call the Buckeye in 1895. Lambert's first automobile marketing success was a model called the Union which was released in 1902. In 1906, he produced the first Lambert. With this line Lambert established himself as one of the more successful automobile manufacturers of the era. In addition to cars, Lambert produced auto fire engines, trucks, gasoline engines and Steel-hoof farm tractors. The Buckeye Manufacturing Company produced the Lambert automobile through 1917, with the maximum production from 1907-1910, when the firm produced an average of 2,000 cars a year.", "Engineering,_Manufacturing": 0.9999415874, "qwen": "Yes"}
{"id": "34200458", "revid": "8766034", "url": "https://en.wikipedia.org/wiki?curid=34200458", "title": "Crown gear", "text": "A crown gear (also known as a face gear or a contrate gear) is a gear which has teeth that project at right angles to the face of the wheel. In particular, a crown gear is a type of bevel gear where the pitch cone angle is 90 degrees. A pitch cone of any other angle is simply called a bevel gear. Crown gears normally mesh with other bevel gears, or sometimes spur gears, a typical use being a crown gear and pinion system which allows a rotary motion to be shifted 90 degrees.", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "15443272", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=15443272", "title": "Epoxy granite", "text": "Epoxy granite, also known as synthetic granite, is a polymer matrix composite and is a mixture of epoxy and granite commonly used as an alternative material for machine tool bases. Epoxy granite is used instead of cast iron and steel for improved vibration damping, longer tool life, and lower assembly cost, and thus better properties for stabilizing and housing machines.\nMachine tool base.\nMachine tools and other high-precision machines rely upon high stiffness, long-term stability, and excellent damping characteristics of the base material for their static and dynamic performance. The most widely used materials for these structures are cast iron, welded steel fabrications, and natural granite. Due to the lack of long-term stability and very poor damping properties, steel fabricated structures are seldom used where high precision is required. Good-quality cast iron that is stress-relieved and annealed will give the structure dimensional stability, and can be cast into complex shapes, but needs an expensive machining process to form precision surfaces after casting. Natural granite has a higher damping capacity than cast iron, but similarly to cast iron can be labor-intensive and expensive to machine and finish. The traditional market for epoxy granite is to replace iron and steel in these applications.\nProcess.\nPrecision granite castings are produced by mixing granite aggregates (which are crushed, washed, and dried) with an epoxy resin system at ambient temperature (i.e., cold curing process). Quartz aggregate filler can also be used in the composition. Vibratory compaction during the molding process tightly packs the aggregate together. Mechanical and thermo-mechanical properties can be improved further if fiber is used as well as the granite. Other resins in addition to the epoxy may also be used instead of fibers to improve properties such as water absorption. If porosity is controlled, damping effects can be improved further. Threaded inserts, steel plates, and coolant pipes can be cast-in during the casting process. To achieve an even higher degree of versatility, linear rails, ground slide-ways, and motor mounts can be replicated or grouted-in, therefore eliminating the need for any post-cast machining.\nOther definitions.\nEpoxy resins and granite, specifically waste granite dust, may be used in other applications such as floor coatings. Waste granite filings are produced in the mining industry and the low density means this can be easily dispersed by winds and thus distributed in the environment. Research is being done on innovative solutions such as using waste granite powders in epoxy resins and designing binders for coatings based on this.\nAdvantages over iron and its alloys.\nThe vibration damping of epoxy granite is often claimed to be superior to that of steel or cast iron It is also well known that iron and steel and alloys corrode or rust, whereas epoxy is often used to prevent corrosion. So, the corrosion and general chemical resistance of epoxy granite to most common solvents, acids, alkalis, and cutting fluids is superior to steel and alloys and does not require constant painting. Epoxy granite material has an internal damping factor up to ten times better than cast iron, up to three times better than natural granite, and up to thirty times better than steel fabricated structure. The method of casting compared to steel allows easier inclusion of inserts etc. and thus reduced machining of the finished casting and reduced assembly time by incorporating multiple components into one casting. Polymer cast resins use very little energy to produce, and the casting process is done at room temperature.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "15463121", "revid": "7770027", "url": "https://en.wikipedia.org/wiki?curid=15463121", "title": "Work in process", "text": "Work in process or work-in-process, (WIP), work in progress (WIP), goods in process, or in-process inventory refers to a company's partially finished goods waiting for completion and eventual sale, or the value of these items. The term is used in supply chain management, and WIP is a key input for calculating inventory on a company's balance sheet. In lean thinking, inappropriate processing or excessive processing of goods or work in process, \"doing more than is necessary\", is seen as one of the seven wastes (Japanese term: \"muda\") which do not add value to a product.\nWIP inventory in supply chain management.\nWIP inventory calculations can help a company assess their supply chain health and guide in supply chain planning. In most cases, it is ideal to have low WIP inventory levels, and companies that manage their inventory level efficiently tend to have lower costs. Managing WIP inventory requires coordination between several functions within a company, as well as with suppliers and customers. Higher WIP inventory levels are advantageous in that they can support a surge in demand, as well as improve cycle time since there is more material in production. However, this can also increase storage costs and obsolescence risk, as well as lead to waste if demand is lower than expected.\nWIP inventory in accounting.\nWIP inventory refers to goods that are in production and not yet a finished good. On the balance sheet, WIP inventory is aggregated into the inventory line under current assets along with raw materials and finished goods.\nTo calculate WIP inventory at the end of an accounting period, the following 3 figures are required: beginning WIP inventory, production costs, and finished goods. Beginning WIP inventory is the WIP inventory figure from the previous accounting period. Production costs includes all costs associated with manufacturing a product, such as raw materials, labor, and overhead costs. Finished goods is the total value of goods ready for sale in the current accounting period. The formula for calculating WIP inventory is as follows: beginning WIP inventory + production costs – finished goods.\nTax treatment.\nIn the United Kingdom, HMRC has no specific definition of work-in-process, but three different types of uncompleted items are identified for tax purposes:", "Engineering,_Manufacturing": 0.9999952316, "qwen": "Yes"}
{"id": "3053158", "revid": "1749459", "url": "https://en.wikipedia.org/wiki?curid=3053158", "title": "Gantry crane", "text": "A gantry crane is a crane built atop a gantry, which is a structure used to straddle an object or workspace. They can range from enormous \"full\" gantry cranes, capable of lifting some of the heaviest loads in the world, to small shop cranes, used for tasks such as lifting automobile engines out of vehicles. They are also called portal cranes, the \"portal\" being the empty space straddled by the gantry.\nThe terms gantry crane and overhead crane (or bridge crane) are often used interchangeably, as both types of crane straddle their workload. The distinction most often drawn between the two is that with gantry cranes, the entire structure (including gantry) is usually wheeled (often on rails). By contrast, the supporting structure of an overhead crane is fixed in location, often in the form of the walls or ceiling of a building, to which is attached a movable hoist running overhead along a rail or beam (which may itself move). Further confusing the issue is that gantry cranes may also incorporate a movable beam-mounted hoist in addition to the entire structure being wheeled, and some overhead cranes are suspended from a freestanding gantry.\nVariants.\nShip-to-shore gantry crane.\nShip-to-shore gantry cranes are imposing, multi-story structures prominent at most container terminals, used to load intermodal containers on and off container ships. They operate along two rails (waterside and landside designations) spaced based on the size of crane to be used.\nLateral movement system:\nVertical frame and braces:\nCrane boom:\nHook:\nOperating cabin:\nStorage equipment:\nShip-to-shore gantry cranes are often used in pairs or teams of cranes in order to minimize the time required to load and unload vessels. As container ship sizes and widths have increased throughout the 20th Century, ship-to-shore gantry cranes and the implementation of those gantry cranes have become more individualized in order to effectively load and unload vessels while maximizing profitability and minimizing time in port. One example are systems where specialized berths are built that accommodate one vessel at a time with ship-to-shore gantry cranes on both sides of the vessel. This allows for more cranes and double the workspace under the cranes to be used for transporting cargo off dock.\nThe first quayside container gantry crane was developed in 1959 by Paceco Corporation.\nFull gantry crane.\nFull gantry cranes (where the load remains beneath the gantry structure, supported from a beam) are well suited to lifting massive objects such as ships' engines, as the entire structure can resist the torque created by the load, and counterweights are generally not required. These are often found in shipyards where they are used to move large ship components together for construction. They use a complex system of cables and attachments to support the massive loads undertaken by the full gantry cranes.\nSome full gantry cranes of note are Samson and Goliath and Taisun. Samson and Goliath are two full gantry cranes located in the Harland and Wolff shipyard in Belfast. They have spans of and can lift loads of up to to a height of . In 2008, the world's strongest gantry crane, Taisun, which can lift , was installed in Yantai, China at the Yantai Raffles Shipyard. In 2012, a capacity crane, the \"Honghai Crane\" was planned for construction in Qidong City, China and was finished in 2014.\nRubber-tyred gantry crane.\nSmaller gantry cranes are also available running on rubber tyres so that tracks are not needed. Rubber tyred gantry cranes are essential for moving containers from berths throughout the rest of the yard. For this task they come in large sizes, as pictured to the left, that are used for moving to straddle multiple lanes of rail, road, or container storage. They also are capable of lifting fully loaded containers to great heights. Smaller rubber tyred gantry cranes come in the form of straddle carriers which are used when moving individual containers or vertical stacks of containers.\nPortable gantry crane systems, such as rubber tyred gantry cranes, are in high demand in terminals and ports restricted in size and reliant on maximizing vertical space and not needing to haul containers long distances. This is due to the relatively slow speed yet high reach of rubber tyred gantry cranes when compared to other forms of container terminal equipment.\nPortable gantry crane.\nPortable gantry cranes are used to lift and transport smaller items, usually less than . They are widely used in the HVAC, machinery moving and fine art installation industries. Some portable gantry cranes are equipped with an enclosed track, while others use an I-beam, or other extruded shapes, for the running surface. Most workstation gantry cranes are intended to be stationary when loaded, and mobile when unloaded. Workstation Gantry Cranes can be outfitted with either a wire rope hoist or a lower capacity chain hoist.", "Engineering,_Manufacturing": 1.0000041723, "qwen": "Yes"}
{"id": "3054735", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=3054735", "title": "Upset welding", "text": "Upset welding (UW)/resistance butt welding is a welding technique that produces coalescence simultaneously over the entire area of abutting surfaces or progressively along a joint, by the heat obtained from resistance to electric current through the area where those surfaces are in contact.\nPressure is applied before heating is started and is maintained throughout the heating period. The equipment used for upset welding is very similar to that used for flash welding. It can be used only if the parts to be welded are equal in cross-sectional area. The abutting surfaces must be very carefully prepared to provide for proper heating.\nThe difference from flash welding is that the parts are clamped in the welding machine and force is applied bringing them tightly together. High-amperage current is then passed through the joint, which heats the abutting surfaces. When they have been heated to a suitable forging temperature an upsetting force is applied and the current is stopped. The high temperature of the work at the abutting surfaces plus the high pressure causes coalescence to take place. After cooling, the force is released and the weld is completed.", "Engineering,_Manufacturing": 0.9983873367, "qwen": "Yes"}
{"id": "32457345", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=32457345", "title": "Photonic curing", "text": "Photonic curing is the high-temperature thermal processing of a thin film using pulsed light from a flashlamp. When this transient processing is done on a low-temperature substrate such as plastic or paper, it is possible to attain a significantly higher temperature than the substrate can ordinarily withstand under an equilibrium heating source such as an oven. Since the rate of most thermal curing processes (drying, sintering, reacting, annealing, etc.) generally increase exponentially with temperature (i.e. they obey the Arrhenius equation), this process allows materials to be cured much more rapidly than with an oven.\nIt has become a transformative process used in the manufacture of printed electronics as it allows inexpensive and flexible substrates to be substituted for traditional glass or ceramic substrates. Additionally, the higher temperature processing afforded by photonic curing reduces the processing time exponentially, often from minutes down to milliseconds, which increases throughput all while maintaining a small machine footprint.\nHeat Transfer Dynamics.\nPhotonic curing primarily relies on radiative heat transfer from the lamp to the object of interest during the time that the flashlamp is on, usually between 100 μs and 100 ms. After radiative heat impinges on this object, thermal conduction through the object and convective loss to the atmosphere in contact with the material will occur until the object nears thermal equilibrium. Because of the intensity and short duration of the flashlamp pulse, extreme thermal gradients can occur in the object of interest. Those extreme gradients can be useful in exposing only certain parts of an object to high temperatures. \nFor most applications of photonic curing, designers consider a layered stack of materials. The goal of a curing profile design is to reach sufficient temperature to cause sintering and metalization of a top layer or print, while avoiding exceeding the glass transition temperature, melting temperature, or flash point of the layers beneath. The transient thermal process of dissipating the heat delivered by the flashlamp depends, again, on the convective thermal losses from the top and bottom layers of the material of interest, and on the thickness of each layer. For thick layers or layers with low thermal conductivity, heat can be dissipated before the temperature of lower layers in the stack can exceed a glass transition or melting temperature. This is the key feature of photonic curing that allows for the curing of metals and conductive inks and paste on low temperature materials.\nUses.\nPhotonic curing is used as a thermal processing technique in the manufacturing of printed electronics as it allows the substitution of glass or ceramic substrate materials with inexpensive and flexible substrate materials such as polymers or paper. The effect can be demonstrated with an ordinary camera flash. Industrial photonic curing systems are typically water cooled and have controls and features similar to industrial lasers. The pulse rate can be fast enough to allow curing on the fly at speeds beyond 100 m/min making it suitable as a curing process for roll-to-roll processing. Material processing rates can exceed 1 m2/s.\nThe maturing complexity of modern printed electronics for customer applications demands high throughput manufacturing and improved device function. The functionality of the printed electronics is critically important as customers demand more out of each device. Multiple layers are designed into each device, requiring ever more versatile processing techniques. Photonic curing is uniquely suited to complement the processing needs in the manufacture of modern printed electronics by providing a fast, reliable and transformative processing step. Photonic curing enables a lower thermal processing budget with current materials, and it can provide a path to incorporate more advanced materials and functionality into future printed electronics.\nDevelopment.\nPhotonic curing is similar to Pulse Thermal Processing, developed at Oak Ridge National Laboratory, in which a plasma arc lamp is used. In the case of photonic curing, the radiant power is higher and the pulse length is shorter. The total radiant exposure per pulse is less with photonic curing, but the pulse rate is much faster.", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "32485676", "revid": "1143033826", "url": "https://en.wikipedia.org/wiki?curid=32485676", "title": "Rapper (electrostatic precipitation)", "text": "Rappers are used to transmit strong shearing forces to collecting plates in order to release deposited dust particles. Rapping is the process by which electrodes and particles are broken apart by vibrations from the rappers. Often used in electrostatic precipitators, rappers relapse the caked on dust layer which then descends into a hopper. Number, size, and frequency of the rappers vary from system to system based upon the specific characteristics of the dust being collected.\nRappers & precipitators.\nTypically such vibrators are employed in conjunction with electrostatic precipitators. Precipitators contain sheet metal collector electrode plates. Vertically suspended discharge electrode wires are located between the plates. As a gas stream, often discharged from an industrial process, flows through the precipitator, air particulates are ionized by the electrode wire. The ionized particles then are attracted to the positively grounded plate, creating a layer of caked on dust particles. Rappers are responsible for Transmitting vibrations to the electrodes causing deposited dust particles to break loose and fall into a hopper located below the precipitator.\nTypes.\nGenerally the three types of rappers are:\nElectric vibrators use rods that extend through the precipitator shell to transmit vibrations to the discharge wires and/or collecting plates and are not typically used in scenarios involving fly ash. The electromagnetic vibrator consists of a coil that is energized by alternating current. The energy creates a vibration transmitted through a rod to the wires or plates.\nMechanical rappers consist of a large weight that is lifted to gain potential energy and then released, allowing it to fall and collide with an anvil creating a shock to dislodge caked-on dust.\nPneumatic rappers can be either type, vibratory or impact.\nTumbling hammers, typically used in conjunction with rigid frame discharge electrodes, are highly efficient but require a lot of maintenance when employed in a moving gas stream. Hammers are connected to a rotating shaft. As they revolve, the hammers collide with a beam, causing a vibratory shock to dislodge caked-on dust. The hammer’s weight and mounting arm length control the intensity of the rapping. Adjusting the speed of the rotating shaft alters the frequency of rapping.\nDesign considerations.\nRapping systems are designed primarily based on two factors, the internal suspension system and the number of surfaces affected by the rapping vibrations. Pneumatic rappers apply the greatest shock. The materials and design of a rapper system must be able to withstand high energy forces. Moreover, dust must be dislodged successfully without causing a lot of re-entrainment.\nEach installation has a unique intensity and period of vibration at which the system will produce the greatest collecting efficiency. For example, low intensity causes significant buildup of dust on discharge wires ultimately limiting the power input to the precipitator due to a reduction in sparkover distance between electrodes. Furthermore, low intensity represses the formation of negative corona. Buildup can also affect the standard distribution of electrostatic forces, thereby causing oscillation of the discharge wires and high-tension frame.\nThe intensity of the vibrations is regulated via adjustments in air pressure to provide diversity in force needed to clean various types of discharge electrode systems. This feature allows for rapping of event the most delicate systems.\nRapping plays a key role in total emissions due to re-entrainment. Therefore, the rapping system must be designed and adjusted to minimize re-entrainment of particles into the gas stream.\nCommon weaknesses.\nEssentially, the high energy repeated motion created by the rappers is the source of their wear. The consistent high intensity vibrations cause fatigue and wear on the rappers. Bolted joints are especially affected by this repetitive motion and must be replaced. Frequent failure of air in inlet fittings is another issue that arises from the motion. Repeated vibrations cause fittings to dull down and pipe threads break off, therefore, loosening the fittings.", "Engineering,_Manufacturing": 0.9999474287, "qwen": "Yes"}
{"id": "35708001", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=35708001", "title": "Avo Photonics", "text": "Avo Photonics, Inc. is a service corporation that designs, develops, and manufactures private-label opto-electronic products for the medical, industrial, defense, aerospace, and communication markets.\nThe company headquarters is located in Horsham, PA, a suburb of Philadelphia, and consists of a manufacturing facility that features of clean room space.\nAdditional design verification is performed at Avo's satellite campus in Toronto, Ontario, and the company has European distributorship in Germany, France, Spain, the United Kingdom, Italy, and Norway.\nHistory.\nAvo Photonics was founded in 2003 by a group of engineers and laser physicists led by Dr. Joseph L. Dallas, co-creator of NASA's Space Lidar Technology Center. Avo was acquired by Halma, p.l.c., in 2011 as part of their global photonics division.\nDesign and development capability.\nAvo Photonics' design and development capabilities include optical, mechanical, thermal, and electrical modeling and design integration, as well as prototyping and testing.\nManufacturing capability.\nAvo Photonics is ISO 9001:2008-certified and -certified. Its manufacturing capabilities include die bonding, laser welding, hermetic sealing, wire and ribbon bonding, fiber attach, vacuum packaging, and test and burn-in. In the past, Avo has manufactured such optical components and systems as diode-pumped solid-state lasers, fiber amplifiers, laser projector sources, high power isolators, tunable lasers, IR imagers, Lidar systems, Reagent photometers and space/airborne rangers.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "543125", "revid": "19090830", "url": "https://en.wikipedia.org/wiki?curid=543125", "title": "Brake (sheet metal bending)", "text": "A brake is a metalworking machine that allows the bending of sheet metal. A cornice brake only allows for simple bends and creases, while a box-and-pan brake also allows one to form box and pan shapes. It is also known as a bending machine or bending brake or in Britain as a sheet metal folder or just a folder.\nDescription.\nThe brake consists of a flat surface onto which the material is placed, and a clamping bar which will come down and hold the material firmly during the bend. This clamping action may be manual, automatic or operated using a foot pedal. The front, gate-like, plate of the machine is hinged and may be lifted, forcing the material extended over a straight edge to bend to follow the plate.\nThe bends can be to any angle up to a practical limit of about 120 degrees, somewhat more in the case of a bar folder. If the area to be bent is narrow enough, a sharper bend (e.g., for a hem) can be made by inserting the bend under the clamping bar and lowering it.\nBox-and-pan brake.\nIn a box-and-pan brake (also known as a finger brake), the clamping bar includes several removable blocks, which may be removed and rearranged to permit bending of restricted areas of a piece of sheet metal or of already partially formed pieces.\nAfter bending, the box or pan form is then completed by screw, solder, weld, rivet, or other metal fixing process.\nBar folder.\nA bar folder is a simplified brake, usually much smaller than a cornice or box-and-pan brake. Typically, a single handle both clamps the workpiece and makes the bend, in a single motion. There is a gauge that can be set up to a depth up to one inch for consistent bends.\nExamples of items a bar folder is used to fabricate would be end caps, \"s\" cleats, and drive cleats.\nPress brake.\nThis is a more complex tool that forms predetermined bends by clamping the workpiece between a matching punch and die.\nSizes.\nBrakes come in sizes suitable for light aluminum or brass for small boxes and operated by hand, up to industrial sized and counterweighted hand-operated or hydraulic machines suitable for large sheets of steel.", "Engineering,_Manufacturing": 1.0000065565, "qwen": "Yes"}
{"id": "635183", "revid": "1107062598", "url": "https://en.wikipedia.org/wiki?curid=635183", "title": "Grind", "text": "A blade's grind is its cross-sectional shape in a plane normal to the edge. Grind differs from blade profile, which is the blade's cross-sectional shape in the plane containing the blade's edge and the centre contour of the blade's back (meaning the shape of the blade when viewed from the side, i.e. clip point, spear point, etc.). The \"grind\" of a blade should not be confused with the bevel forming the sharpened edge; it more usually describes the overall cross-section of the blade, not inclusive of the beveled cutting edge which is typically of a different, less acute angle as the bevel ground onto the blade to give it a cross-sectional shape. For example, the famous Buck 110 hunting knife has a \"hollow ground\" blade, with concave blade faces (which aid in slicing through materials), but the cutting edge itself is a simple, flat-ground bevel of lesser angle. It would be difficult, if not impossible, to put a \"hollow grind\" onto the actual cutting edge of the blade itself, which is a very narrow and small bevel.\nGrinding.\nGrinding is the process of creating grinds. It involves removing significant portions of material from a blade, which distinguishes it from honing and polishing. Blades are ground during their initial sharpening or after having been sufficiently damaged, such as by breaking a tip, chipping, or extensive corrosion. Well-maintained blades need grinding less frequently than neglected or maltreated ones do.\nEdge angle and included angle typically characterize a blade's grind. An edge angle is measured between a line lying in the plane of one of the edge's faces and a second line intersecting the back's centre contour, both lines lying in the same plane normal to the edge. The included angle is the sum of the edge angles. Ceteris paribus, the smaller the included angle, the sharper the blade and the more easily damaged its edge.\nAn appropriate grind depends upon a blade's intended use and the material composing it. Knife manufacturers may offer the same blade with different grinds and blade owners may choose to regrind their blades to obtain different properties. A trade-off exists between a blade's ability to take an edge and its ability to keep one. Some grinds are easier to maintain than others, better retaining their integrity as repeated sharpening wears away the blade. Harder steels take sharper edges, but are more brittle and hence chip more easily, whereas softer steels are tougher. The latter are used for knives such as cleavers, which must be tough but do not require a sharp edge. In the range of blade materials' hardnesses, the relationship between hardness and toughness is fairly complex and great hardness and great toughness are often possible simultaneously.\nAs a rough guide, Western kitchen knives are generally double-bevelled (about 15° on the first bevel and 20°–22° on the second), whereas East Asian kitchen knives, made of harder steel and being either wedge- (double-ground) to 15°–18° or chisel-shaped (single-ground) to 20°–30°.\nCare should be taken to avoid confusing the grind of the blade as describing its cross-section and the angle that is ground onto the edge to form a cutting edge. It is very rare to have a knife with a single ground angle forming both the profile and the cutting edge (the exception being perhaps straight razors). For example, the famous Buck 110 folding hunting knife is described as having a \"hollow grind\" - meaning the faces of the blade are ground into a concave – but the blade also contains a second, less acute, conventional bevel that makes up the cutting edge. A classic Opinel folding knife has a \"flat grind\" blade, meaning that the faces of the blade are flat, without convexity or concavity, tapering towards the cutting edge: but the actual cutting edge is again formed of another, less acute bevel ground on the narrow edge. A classic Morakniv has a saber or \"Scandi\" grind, with flat, perpendicular sides on the body, with a secondary bevel formed below to create a tapered edge, but again, the actual cutting edge comprises a third, less-acute bevel. Thus the \"grind\" of the blade most often refers to the overall cross-section of the blade and should not be confused with the actual style of cutting edge put in the blade, even though this cutting edge is created by grinding as well. If the cutting edge was included in the description of the \"grind\", the vast majority of blades would have to be described as \"compound angle grind\". And of course one can purchase an unsharped blade in any style grind you desire, and there is rarely need to grind the entire surface of the blade to create a cutting edge.\nProcess.\nA sharp object works by concentrating forces which creates a high pressure due to the very small area of the edge, but high pressures can nick a thin blade or even cause it to roll over into a rounded tube when it is used against hard materials. An irregular material or angled cut is also likely to apply much more torque to hollow-ground blades due to the \"lip\" formed on either side of the edge. More blade material can be included directly behind the cutting edge to reinforce it, but during sharpening some proportion of this material must be removed to reshape the edge, making the process more time-consuming. Also, any object being cut must be moved aside to make way for this wider blade section, and any force distributed to the grind surface reduces the pressure applied at the edge.\nOne way around this dilemma is to use the blade at an angle, which can make a blade's grind seem less steep, much as a switchback makes a trail easier to climb. Using the edge in this way is made easier by introducing a curve in the blade, as seen in sabers, tulwars, shamshirs, and katanas, among many others. Some old European swords (most memorably Hrunting) and the Indonesian style of kris have a wavelike shape, with much the same effect in drawing or thrusting cuts.\nIf it is required to measure the angles of cutting edges, it is achieved by using a goniometer, or blade edge protractor.\nTypical grinds.\nTypical grinds include:\nIt is possible to combine grinds or produce other variations. For example, some blades may be flat-ground for much of the blade but be convex ground towards the edge.", "Engineering,_Manufacturing": 0.9999480247, "qwen": "Yes"}
{"id": "14894608", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=14894608", "title": "Number matching", "text": "Number matching or matching numbers is a term often used in the collector car industry to describe cars with original major components, or major components that match one another.\nMany times these major components contain dates, casting numbers, model numbers, Vehicle Identification Numbers (VIN), stamped numbers, or codes that can match the original components that were on the car when it was new.\nDefinition.\nThe term \"number matching\" (or \"matching numbers\") is a term used in the collector car industry to describe the authenticity of collectible or investment quality cars. Number matching generally means that a particular car still contains its original major components or has major components that match exactly the major components the car had when it was new. These \"major components\" are not always agreed on. The appearance of a number matching car likely could not be distinguished from an original car.\nMajor components.\nThese are parts such as the engine, transmission, rear-axle assembly, and frame of the car, with intake manifolds, exhaust manifolds, body panels, and carburetors sometimes also considered. Many times these components contain dates, casting numbers, model numbers, VIN, stamped numbers, or codes that can match the original components that were on the car when it was new.\nThe definition can often vary from manufacturer to manufacturer, as well as from country to country. Often parts such as transmissions and rear-axles will be common across a range of models and as such do not carry any stamped link to the car it was originally installed in.\nIt is widely accepted however that the minimum requirement for a vehicle to be Number matching (or matching numbers, depending on local terminology) is for the original Chassis number and/or Vehicle Identification Number (VIN) to match to the engine block, if that is how the original manufacturer identified it, and the data tags. If the manufacturer did not serialize the engine block, all engineering numbers, casting numbers, date codes and any other numbers used by the original manufacturer must match what would have been original to the vehicle.\nMinor components.\nThese are parts that are commonly replaced due to regular wear and tear. Parts such as the interior fabric, paint, chrome trim, brakes, instruments, electrical components and wiring are considered minor components and generally do not affect the value of the car.\nVerification.\nThe numbers or casting dates on the major components of a car would be present and fall in a particular order.\nFor example, an engine's assembly date would be before the build date of the car, and the casting dates would be before the assembly date of the engine because an engine assembly date (the date the engine was assembled, usually at a different location) could not be after the assembly date of the whole car. Engines are assembled prior to being installed in the car at the factory. Therefore, the assembly date of the car would have to be after the assembly date of the engine. Casting dates (the dates formed in the metal of a component at the foundry) could not be after the assembly date of the engine. And casting dates would be well in advance of the assembly date of the engine. Numbers and dates track an accurate history of how a car was built and when and where the car and the parts used to create the car were made.\nIf a car has number matching major components it helps define how collectible a car is. Number matching cars typically will have a much greater value than non-number matching cars, because they are much rarer than non-number matching cars, and are seen as a more accurate description of how the car was built.", "Engineering,_Manufacturing": 0.9893555045, "qwen": "Yes"}
{"id": "14903275", "revid": "43925848", "url": "https://en.wikipedia.org/wiki?curid=14903275", "title": "DISAMATIC", "text": "DISAMATIC is an automatic production line used for fast manufacturing of sand molds for sand casting. This process is commonly used to mass manufacture of metal castings for the automotive and machine industries.\nHistory.\nIn 1957, Vagn Aage Jeppesen, professor at the Technical University of Denmark, claimed a patent for a device producing flaskless molds of sand mixtures with vertical parting lines for casting metal parts. In 1960, the Danish company Dansk Industri Syndikat A/S (DISA) acquired the patent and started working on its implementation.\nIn 1962, a half scale prototype of a sand molding machine with flaskless and vertically parted molds under the name of DISAMATIC was ready to be disclosed. During the International Foundry Trade Fair (GIFA) in 1962 in Düsseldorf, the scale model was demonstrated on DISA's stand. This resulted in sales of two first DISAMATICs to European foundries. The first automatic DISAMATIC molding lines could produce up to 240 complete sand molds per hour.\nProcess.\nDISAMATIC consists of a molding machine and mold transporting conveyor. A molding sand mixture, usually green sand or bentonite, is blown into a rectangular steel chamber using compressed air. The molding sand is then squeezed between two patterns, which are on the two ends of the chamber. After squeezing, one of the chamber plates swings open and the opposite plate pushes the finished mold onto a conveyor. Finally, any cores are automatically set into the mold cavity while the next mold is being prepared. The cycle repeats until a chain of finished molds butt up to each other on the conveyor.\nThe molds are then filled with molten metal and placed on a cooling conveyor, which moves at the same pace as the fabrication conveyor. At the end of the conveyor the solidified castings are separated from the molds and processed further, while the sand is directed to the sand preparation plant for reconditioning and reuse in the next cycles of the DISAMATIC molding process.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "2891978", "revid": "28254202", "url": "https://en.wikipedia.org/wiki?curid=2891978", "title": "Multi-chip module", "text": "A multi-chip module (MCM) is generically an electronic assembly (such as a package with a number of conductor terminals or \"pins\") where multiple integrated circuits (ICs or \"chips\"), semiconductor dies and/or other discrete components are integrated, usually onto a unifying substrate, so that in use it can be treated as if it were a larger IC. Other terms for MCM packaging include \"heterogeneous integration\" or \"hybrid integrated circuit\". The advantage of using MCM packaging is it allows a manufacturer to use multiple components for modularity and/or to improve yields over a conventional monolithic IC approach.\nOverview.\nMulti-chip modules come in a variety of forms depending on the complexity and development philosophies of their designers. These can range from using pre-packaged ICs on a small printed circuit board (PCB) meant to mimic the package footprint of an existing chip package to fully custom chip packages integrating many chip dies on a high density interconnection (HDI) substrate. The final assembled MCM substrate may be done in one of the following ways:\nThe ICs that make up the MCM package may be:\nThe PCB that interconnects the ICs is known as an interposer. This is often either organic (a laminated circuit board, which contains carbon, hence \"organic\") or is made of silicon (as in High Bandwidth Memory) Both have their advantages and limitations. Using interposers to connect several ICs instead of connecting several monolithic ICs in separate packages reduces the power needed to transmit signals between ICs, increases the amount of transmission channels, and reduces delays caused by resistance/capacitance (RC delays). However, communication between chiplets consumes more power and has higher latency than components within monolithic ICs.\nChip stack MCMs.\nA relatively new development in MCM technology is the so-called \"chip-stack\" package. Certain ICs, memories in particular, have very similar or identical pinouts when used multiple times within systems. A carefully designed substrate can allow these dies to be stacked in a vertical configuration making the resultant MCM's footprint much smaller (albeit at the cost of a thicker or taller chip). Since area is more often at a premium in miniature electronics designs, the chip-stack is an attractive option in many applications such as cell phones and personal digital assistants (PDAs). With the use of a 3D integrated circuit and a thinning process, as many as ten dies can be stacked to create a high capacity SD memory card. This technique can also be used for High Bandwidth Memory.\nThe possible way to increasing the performance of data transfer in the Chip stack is use Wireless Networks on Chip (WiNoC).", "Engineering,_Manufacturing": 0.9999469519, "qwen": "Yes"}
{"id": "60466278", "revid": "1123352931", "url": "https://en.wikipedia.org/wiki?curid=60466278", "title": "Semi-automation", "text": "Semi-automation is a process or procedure that is performed by the combined activities of man and machine with both human and machine steps typically orchestrated by a centralized computer controller.\nWithin manufacturing, production processes may be fully manual, semi-automated, or fully automated. In this case, semi-automation may vary in its degree of manual and automated steps.\nSemi-automated manufacturing processes are typically orchestrated by a computer controller which sends messages to the worker at the time in which he/she should perform a step. The controller typically waits for feedback that the human performed step has been completed via either a human-machine interface or via electronic sensors distributed within the process. Controllers within semi-automated processes may either directly control machinery or send signals to machinery distributed within the process. Centralized computer controllers within semi-automated processes orchestrate processes by instructing the worker, providing electronic communication and control to process equipment, tools, or machines, as well as perform data management to record and ensure that the process meets established process criteria.\nMany manufacturers choose not to fully automate a process, and instead implement semi-automation due to the complexity of the task, or the number of products produced is too low to justify the investment in full automation. Other processes may not be fully automated because it may reduce the flexibility to easily adapt the processes to reflect production needs.", "Engineering,_Manufacturing": 0.9998383522, "qwen": "Yes"}
{"id": "60481301", "revid": "8766034", "url": "https://en.wikipedia.org/wiki?curid=60481301", "title": "UPECA Aerotech", "text": "UPECA Aerotech Sdn. Bhd. informally known as UPECA, is a part of Senior plc. It is the one of Malaysia's largest aerostructure suppliers to Spirit Aerosystems Europe and UTC Aerospace System. UPECA Aerotech's headquarters and manufacturing plant is in Shah Alam, Selangor. UEPECA Aerotech supply aircraft components on Airbus 320, Airbus 330, Airbus 350 and Boeing 787 platforms. A manufacturing plant will be opened near Subang Airport in order to serve UPECA’s manufacturing, storage and distribution of aerospace parts.\nHistory.\nUPECA Technologies, the parent company, was incorporated in 1990. UPECA Aerotech was established in 2005 in order to support the Malaysian government's aspirations to develop the nation's aerospace manufacturing industry. Senior plc, a United Kingdom maker of parts for the aircraft and the vehicle industries, bought UPECA Technologies in order to expand its business in the growing Asian market.", "Engineering,_Manufacturing": 0.9999053478, "qwen": "Yes"}
{"id": "60487602", "revid": "16772485", "url": "https://en.wikipedia.org/wiki?curid=60487602", "title": "Liquid additive manufacturing", "text": "Liquid additive manufacturing (LAM) is an additive manufacturing technique which deposits a liquid or high viscosity material (e.g Liquid Silicone Rubber) onto a build surface to create an object which then vulcanised using heat to harden the object. The process was originally created by Adrian Bowyer and was then built upon by the company German RepRap.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "12662939", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=12662939", "title": "Minco Products", "text": "Minco is a privately owned company with over 650 employees worldwide. Based in Fridley, Minnesota, the company designs and manufactures flexible printed circuit boards and interconnects, RTD based temperature sensors and assemblies, and thermal solutions for medical, defense, aerospace, industrial, and food service applications.\nCompany history.\nMinco Products, Inc was founded by Karl Schurr on October 2, 1956, as an engineering firm, designing and building precision electromechanical devices on a subcontract basis. In 1958, the company decided to concentrate on the development of proprietary products. One of the first efforts was flexible wire-wound temperature sensors for aerospace guidance systems, which led to the development of flexible heaters, introduced by Minco in 1960.\nAlso during the 1960s & 1970s, the temperature sensor line was expanded to include industrial RTD probes, bearing sensors, and RTD stator sensors to which the company supplied to large rotating apparatus (generators) manufacturers (GE, Westinghouse, Reliance Electric, Brown Boveri) and energy management system contractors. The company’s heater product line also expanded into commercial, aerospace and medical applications. Minco's combination etched foil heater-platinum wire sensors were used on many NASA projects including the 1976 Viking Lander (heated soil samples) and Skylab (Inertial Guidance System). Of note, NASA investigated Minco due to the erratic gyros on Skylab causing spacewalks to replace the IGS. The heater-sensor was found not to be the problem. Minco also manufactured one of the first etched foil heaters for early \"wet\" copy machines made by 3M. They opened their second manufacturing facility for this production.\nIn 1974, the company adapted its precision etching and laminating expertise to the manufacture of flexible printed circuits. These first circuits served as interconnects in cardiac pacemakers. Temperature instruments (transmitters, meters, controllers, and alarms) were also added in the 1970s.\nRecent products include optically-clear heaters, HDI and rigid-flex circuits, isolated temperature transmitters, and high temperature RTD elements.\nKarl Schurr remained as company president until his death in 1999 at which time his son, Dana Schurr, assumed the role of president.\nCorporate business units.\nMinco's Thermofoil Heater Business Unit is the world's largest manufacturer of polyimide (Kapton) insulated etched foil heaters. They are generally used in applications where low weight, low profile and high energy efficiency, as well as precision conductive heat input are more critical than cost. One example of this would be Medical diagnostic equipment. They also sell transparent heaters, silicone rubber insulated heaters, high temperature mica insulated heaters and a unique thick film on aluminum heaters.\nMinco's Flex Circuits Business Unit designs and manufactures custom flexible circuits for high-end applications for use in critical medical and defense products.\nThe Temperature Sensors & Instruments Business Unit manufactures custom temperature elements and assemblies for the rotating equipment industry (large generators, turbines and motors). It also sells customized temperature and relative humidity sensors, temperature transmitters and signal processing, transmitting, temperature monitoring, control and alarm solutions.", "Engineering,_Manufacturing": 0.9997958541, "qwen": "Yes"}
{"id": "23081705", "revid": "23762609", "url": "https://en.wikipedia.org/wiki?curid=23081705", "title": "Dymo Corporation", "text": "Dymo Corporation is an American manufacturing company of handheld label printers and thermal-transfer printing tape as accessory, embossing tape label makers, and other printers such as CD and DVD labelers and durable medical equipment.\nThe company is a subsidiary of Newell Brands.\nHistory.\nDymo Industries, Inc. was founded in 1958 to produce handheld tools that use embossing tape. The embossing tape and handheld plastic embossing labeler was invented by David Souza from Oakland, California.\nThe company was acquired by Esselte in 1978 and battery-powered printers became a major product after 1990. The corporation was sold to Newell Rubbermaid in 2005.\nLabel sizes.\nFollowing is a list of the label sizes popular for their LabelWriter (400, 450) printer series:\nCriticism.\nThe LabelWriter 550 and 5XL has a RFID reader that reads RFID tags embedded in Dymo genuine label rolls to automatically detect the label type inside. However, this is also to prevent the use of third-party compatible label rolls, a form of digital rights management similar to inkjet printer cartridges and laser printer cartridges containing a chip to prevent the designing and manufacturing of third-party cartridges. Dymo has received criticism for using a razor and blades model by forcing customers to purchase genuine Dymo label rolls.", "Engineering,_Manufacturing": 0.9997138381, "qwen": "Yes"}
{"id": "23096330", "revid": "1140586332", "url": "https://en.wikipedia.org/wiki?curid=23096330", "title": "MFG.com", "text": "MFG.com is a global online manufacturing marketplace that connects buyers of custom manufactured parts with manufacturers and job shops that provide contract manufacturing services. Buyers are typically engineers and purchasers from major corporations, industrial designers, and other sourcing professionals who post requests for quotes (RFQs) to the marketplace. RFQs then receive quotes from qualified contract manufacturers located around the world. MFG.com is headquartered in Marietta, Georgia, USA, and maintains an office in Paris, France.\nHistory.\nMFG.com was founded by Mitch Free in 1999. The first site transaction between a custom parts buyer and custom parts manufacturer took place on February 14, 2000. Coined the 'Valentine Parts Order,' Free bootstrapped & grew the company to a profitable business over 4 years. In 2005, MFG.com accepted an investment from Jeff Bezos of Bezos Expeditions. In June 2006, MFG.com acquired Geneva based SourcingParts.com, a SaaS company focused on building advanced supplier relationship solutions for the made-to-order parts community.\nIn October 2006, the MFG.com Global Manufacturing Marketplace opened its second largest office in Shanghai, which closed in 2015 for business realignment. In 2007, Samwer Brothers invested in the company, followed by Fidelity Ventures' $26M investment in 2008. Members of Bezos Expeditions and Fidelity Ventures currently sit on the MFG.com board of directors. In September 2012, General Wesley Clark joined the board as an advisory board member. In 2013 founder Mitch Free left MFG.com to pursue other entrepreneurial interests.\nMFG.com was named by Business 2.0 in 2006 as one of the 15 companies that will change the world. In 2017, MFG.com was named to SupplyChainBrain's Top 100 Great Supply Chain Partner List\nIn 2022, MFG.com was acquired by Shapeways.\nBusiness Model.\nBuyers of Custom Manufactured Parts\nEngineers and sourcing professionals use MFG.com to source custom manufactured parts, as well as find and connect with contract manufacturers and manufacturing job shops around the world. Buyers upload their requests for quotation (RFQs) online and connect with suppliers that meet their specific manufacturing specifications. Buyers have the ability to connect with job shops and contract manufacturers based on geographic location, certifications, and manufacturing capabilities. Buyers can also request job shops and contract manufacturers sign electronic non-disclosure agreement (NDA) forms so that they can control how, when, where, and by whom their drawings and documents are viewed.\nEngineers and sourcing professionals can source custom parts in categories such as: \nProviders of Contract Manufacturing Services\nContract manufacturers, job shops, and suppliers of custom manufactured parts have full access to the RFQs being sourced by members of the MFG.com buyer community. Those providers of manufacturing services can search for RFQs based on factors like geography, category, material quantity, part size, or a combination of the four. A profile is created for the manufacturing services provider where they can be found by sourcing professionals on search engines like Google, Bing, and Yahoo. There is an annual subscription for job shops, suppliers, and contract manufacturers to use MFG.com.", "Engineering,_Manufacturing": 0.9998588562, "qwen": "Yes"}
{"id": "2681475", "revid": "30562270", "url": "https://en.wikipedia.org/wiki?curid=2681475", "title": "Via (electronics)", "text": "A via (Latin, 'path' or 'way') is an electrical connection between two or more metal layers, and are commonly used in printed circuit boards. Essentially a via is a small drilled hole that goes through two or more adjacent layers; the hole is plated with metal (often copper) that forms an electrical connection through the insulating layers.\nVias are important for PCB manufacturing. This is because the vias are drilled with certain tolerances and may be fabricated off their designated locations, so some allowance for errors in drill position must be made prior to manufacturing or else the manufacturing yield can decrease due to non-conforming boards (according to some reference standard) or even due to failing boards. In addition, regular through hole vias are considered fragile structures as they are long and narrow; the manufacturer must ensure that the vias are plated properly throughout the barrel and this in turn causes several processing steps.\nIn printed circuit boards.\nIn printed circuit board (PCB) design, a via consists of two pads in corresponding positions on different copper layers of the board, that are electrically connected by a hole through the board. The hole is made conductive by electroplating, or is lined with a tube or a rivet. High-density multilayer PCBs may have microvias: blind vias are exposed only on one side of the board, while buried vias connect internal layers without being exposed on either surface. Thermal vias carry heat away from power devices and are typically used in arrays of about a dozen.\nA via consists of:\nA via, sometimes called PTV or plated-through-via, should not be confused with a plated through hole (PTH). Via is used as an interconnection between copper layers on a PCB while the PTH is generally made larger than vias and is used as a plated hole for acceptance of component leads - such as non-SMT resistors, capacitors, and DIP package IC. PTH can also be used as holes for mechanical connection while vias may not. Another usage of PTH is known as a castellated hole where the PTH is aligned at the edge of the board so that it is cut in half when the board is milled out of the panel - the main usage is for allowing one PCB to be soldered to another in a stack - thus acting both as a fastener and also as a connector.\nThree major kinds of vias are shown in right figure. The basic steps of making a PCB are: making the substrate material and stacking it in layers; through-drilling of plating the vias; and copper trace patterning using photolithography and etching. With this standard procedure, possible via configurations are limited to through-holes. Depth-controlled drilling techniques such as using lasers can allow for more varied via types. (Laser drills can also be used for smaller and more precisely positioned holes than mechanical drills produce.) PCB manufacturing typically starts with a so-called core, a basic double-sided PCB. Layers beyond the first two are stacked from this basic building block. If two more layers are consecutively stacked from bottom of core, you can have a 1-2 via, a 1-3 via and a through hole. Each type of via is made by drilling at each stacking stage. If one layer is stacked on top of the core and other is stacked from the bottom, the possible via configurations are 1-3, 2-3 and through hole. The user must gather information about the PCB manufacturer's allowed methods of stacking and possible vias. For cheaper boards, only through holes are made and antipad (or clearance) is placed on layers which are supposed not to be contacted to vias.\nIPC 4761.\nIPC 4761 defines the following via types:\nFailure behavior.\nIf well made, PCB vias will primarily fail due to differential expansion and contraction between the copper plating and the PCB in the out of plane direction (Z). This differential expansion and contraction will induce cyclic fatigue in the copper plating, eventually resulting in crack propagation and an electrical open circuit. Various design, material, and environmental parameters will influence the rate of this degradation. To ensure via robustness, IPC sponsored a round-robin exercise that developed a time to failure calculator.\nVias in integrated circuits.\nIn integrated circuit (IC) design, a via is a small opening in an insulating oxide layer that allows a conductive connection between different layers. A via on an integrated circuit that passes completely through a silicon wafer or die is called a through-chip via or through-silicon via (TSV). Through-glass vias (TGV) have been studied by Corning Glass for semiconductor packaging, due to the reduced electrical loss of glass versus silicon packaging. A via connecting the lowest layer of metal to diffusion or poly is typically called a \"contact\".", "Engineering,_Manufacturing": 1.0000056028, "qwen": "Yes"}
{"id": "2684396", "revid": "1157464381", "url": "https://en.wikipedia.org/wiki?curid=2684396", "title": "Brush (electric)", "text": "A brush or carbon brush is an electrical contact which conducts current between stationary wires and moving parts, most commonly in a rotating shaft. Typical applications include electric motors, alternators and electric generators. The lifespan of a carbon brush depends on how much the motor is used, and how much power is put through the motor.\nEtymology.\nFor certain types of electric motors or generators to function, the coils of the rotor must be connected to complete an electrical circuit. Originally this was accomplished by affixing a copper or brass commutator or 'slip ring' to the shaft, with springs pressing braided copper wire 'brushes' onto the slip rings or commutator which conduct the current. Such brushes arced and even welded as the commutator rotated, because the brush short–circuited adjacent segments. \nThe cure was the introduction of 'high resistance brushes' made from graphite (sometimes with added copper). Although the resistance was of the order of tens of milliohms, they were high resistance enough to provide a gradual shift of current from one commutator segment to the next.\nCarbon brushes are available in four main grade categories: carbon graphite, electrographitic, graphite, and metal graphite. The term \"brush\" remains in use. Since the brushes wear out, they can be replaced in products intended to allow maintenance.\nDuring World War II, high–altitude aircraft generators had very rapid brush wear, requiring reformulated brush compounds for acceptable life.\nMetal fiber brushes are currently being developed. They may have advantages over current brush technology, but have not yet seen wide implementation.\nManufacturing process.\nMixing components.\nExact composition of the brush depends on the application. Graphite/carbon powder is commonly used. Copper is used for better conductance (rare for AC applications). In order to maximize electrical conductivity and green strength, highly dendritic (electrolytic) copper powder is used. Binders, mostly phenol or other resins or pitch, are mixed in so the powder holds its shape when compacted. Other additives include metal powders, and solid lubricants like MoS2, WS2. Much know-how and research is needed in order to define a brush grade mixture for each application or motor.\nCompacting the mixture.\nThe brush compound is compacted in a tool consisting of upper and lower punch and die, on mechanical or hydraulic presses. In this step, depending on later processing, the copper wire (called shunt wire) can be inserted automatically through a hole in the upper punch and fixed into the pressed brush block by the powder pressed around. This operation, called \"tamping\", is usually performed using electrolytic copper powder, possibly with silver coating for some high performance applications. After this process, the brush is still very fragile and in professional jargon called a 'green brush'.\nFiring of green brushes.\nNext follows heat treatment of the \"green brushes\" under artificial atmosphere (usually hydrogen and nitrogen). Temperatures range up to 1200 °C. This process is called sintering or baking. During sintering, the binders either burn off or carbonize and form a crystalline structure between the carbon, copper and other additives. Baking is followed by graphitization (heat treatment). The heat treatment is transformed by a temperature curve exactly defined for each material mixture. Besides the mixture composition, the used temperature curve is the second big “secret” of each brush manufacturer. After the heat treatment, the brush structure is modified in a way which makes copying of the brush nearly impossible for competing companies.\nSecondary operations.\nSintering causes the brushes to shrink and to bend. They must be ground to net shape. Some companies use additional treatments in order to make the brush more durable by methods such as impregnation of the running surface by special oils, resins and grease.\nManufacturing of carbon brushes requires an in-depth knowledge of materials and experience in mixture compositions. Very small changes in brush contents by just a few percent of components by weight can significantly change the properties of brushes on their applications. There are just a handful of brush developing companies in the world, which are mostly specialized on certain types of brushes.\nCarbon brushes are one of the least costly parts in an electric motor. On the other hand, they usually are the key part which delivers the durability (“life-time”) and performance to the motor they are used in. Their production requires very high attention to quality control and production process control throughout all steps of the production process.\nLiquid metal brushes.\nFrom time to time the use of liquid metals to make contacts is researched. Drawbacks to this approach include the need to contain the liquid metal (as it is usually toxic or corrosive) and power losses from induction and turbulence.", "Engineering,_Manufacturing": 0.9999220371, "qwen": "Yes"}
{"id": "4841771", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=4841771", "title": "Stamping (metalworking)", "text": "Stamping (also known as pressing) is the process of placing flat sheet metal in either blank or coil form into a stamping press where a tool and die surface forms the metal into a net shape. Stamping includes a variety of sheet-metal forming manufacturing processes, such as punching using a machine press or stamping press, blanking, embossing, bending, flanging, and coining. This could be a single stage operation where every stroke of the press produces the desired form on the sheet metal part, or could occur through a series of stages. The process is usually carried out on sheet metal, but can also be used on other materials, such as polystyrene. Progressive dies are commonly fed from a coil of steel, coil reel for unwinding of coil to a straightener to level the coil and then into a feeder which advances the material into the press and die at a predetermined feed length. Depending on part complexity, the number of stations in the die can be determined.\nStamping is usually done on cold metal sheet. See Forging for hot metal forming operations.\nHistory.\nIt is believed that the first coins were struck by the Lydians in what is modern-day Turkey in the seventh century B.C. Until 1550, the hammering method of coins remained the primary method of coin-making. Marx Schwab in Germany developed a new process for stamping that involved as many as 12 men turning a large wheel to press metal into coins. In the 1880s, the stamping process was further innovated. \nStamped parts were used for mass-produced bicycles in the 1880s. Stamping replaced die forging and machining, resulting in greatly reduced cost. Although not as strong as die forged parts, they were of good enough quality.\nStamped bicycle parts were being imported from Germany to the United States in 1890. U.S. companies then started to have stamping machines custom built by U.S. machine tool makers. Through research and development, Western Wheel was able to stamp most bicycle parts.\nSeveral automobile manufacturers adopted stamping of parts. Henry Ford resisted the recommendations of his engineers to use stamped parts, but when his company could not satisfy demand with die forged parts, Ford was forced to use stamping.\nOver the history of metal stamping, forging and deep drawing, presses of all types are the backbone of metals manufacturing. The processes continue to improve in moving more metal in one press stroke. Press and interconnected automation devices increase production rates, reduce labor costs and provide more safety for workers.\nOperation.\nPiercing and cutting can also be performed in stamping presses. Progressive stamping is a combination of the above methods done with a set of dies in a row through which a strip of the material passes one step at a time.\nLubricant.\nThe Tribology process generates friction which requires the use of a lubricant to protect the tool and die surface from scratching or galling. The lubricant also protects the sheet metal and finished part from the same surface abrasion as well as facilitate elastic material flow preventing rips, tears and wrinkles. There are a variety of lubricants available for this task. They include plant and mineral oil-based, animal fat or lard-based, graphite-based, soap and acrylic-based dry films. The newest technology in the industry is polymer-based synthetic lubricants also known as oil-free lubricants or non-oil lubricants. The term \"Water-Based\" lubricant refers to the larger category that also includes more traditional oil and fat-based compounds.\nSimulation.\nSheet metal forming simulation is a technology that calculates the process of sheet metal stamping, predicting common defects such as splits, wrinkles, springback and material thinning. Also known as forming simulation, the technology is a specific application of non-linear finite element analysis. The technology has many benefits in the manufacturing industry, especially the automotive industry, where lead time to market, cost and lean manufacturing are critical to the success of a company.\nRecent research by the Aberdeen research company (October 2006) found that the most effective manufacturers spend more time simulating upfront and reap the rewards towards the end of their projects.\nStamping simulation is used when a sheet metal part designer or toolmaker desires to assess the likelihood of successfully manufacturing a sheet metal part, without the expense of making a physical tool. Stamping simulation allows any sheet metal part forming process to be simulated in the virtual environment of a PC for a fraction of the expense of a physical tryout.\nResults from a stamping simulation allow sheet metal part designers to assess alternative designs very quickly to optimize their parts for low cost manufacture.\nMicrostamping.\nWhile the concept of stamping sheet metal components has traditionally focused on the macro level (e.g. vehicle, aircraft, and packaging applications), the continuing trend of miniaturization has driven research into micro- forms of stamping. From the early development of micropunching machines in the early to mid-2000s to the creation and testing of a microbending machine at Northwestern University in the 2010s, microstamping tools continue to be researched as alternatives to machining and chemical etching. Examples of applications of sheet metal microstamping include electrical connectors, micromeshes, microswitches, microcups for electron guns, wristwatch components, handheld device components, and medical devices. However, key issues such as quality control, high-volume application, and the need for material research into mechanical properties must be addressed before full-scale implementation of the technology is realized.\nIndustry-specific applications.\nMetal stamping can be applied to a variety of materials based on their unique metalworking qualities for a number of applications across a wide range of industries. Metal stamping may require the forming and processing of base common metals to rare alloys for their application-specific advantages. Some industries require the electrical or thermal conductivity of beryllium copper in areas such as aerospace, electrical, and the defense industry, or the high strength application of steel and its many alloys for the automotive industry.\nIndustries metal stamping is used for:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "4842417", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=4842417", "title": "Tape-automated bonding", "text": "Tape-automated bonding (TAB) is a process that places bare semiconductor chips (dies) like integrated circuits onto a flexible circuit board (FPC) by attaching them to fine conductors in a polyamide or polyimide (like trade names Kapton or UPILEX) film carrier. This FPC with the die(s) (TAB inner lead bonding, ILB) can be mounted on the system or module board or assembled inside a package (TAB outer lead bonding, OLB). Typically the FPC includes from one to three conductive layers and all inputs and outputs of the semiconductor die are connected simultaneously during the TAB bonding. Tape automated bonding is one of the methods needed for achieving chip-on-flex (COF) assembly and it is one of the first roll-to-roll processing (also called R2R, reel-to-reel) type methods in the electronics manufacturing.\nProcess.\nThe TAB mounting is done such that the bonding sites of the die, usually in the form of bumps or balls made of gold, solder or anisotropic conductive material, are connected to fine conductors on the tape, which provide the means of connecting the die to the package or directly to external circuits. The bumps or balls can locate either on the die or on the TAB tape. TAB compliant metallizations systems are:\nSometimes the tape on which the die is bonded already contains the actual application circuit of the die. The film is moved to the target location, and the leads are cut and joining the chip takes place as necessary. There are several joining methods used with TAB: thermocompression bonding (with help of a pressure, sometimes called as a gang bonding), thermosonic bonding etc. The bare chip may then be encapsulated (\"glob topped\") with epoxy or similar. \nThe merits of the tape-automated bonding are:\nThe challenges of the tape-automated bonding are:\nStandards.\nStandard sizes for polyimide tapes include widths of 35 mm, 45 mm, and 70 mm and thicknesses between 50 and 100 micrometers. Since the tape is in the form of a roll, the length of the circuit is measured in terms of sprocket pitches, with each sprocket pitch measuring about 4.75 mm. Thus, a circuit size of 16 pitches is about 76 mm long.\nHistory and background.\nTechnically the process was invented by Frances Hugle -patent issued 1969 - although it was not named as TAB. The TAB was first outlined by Gerard Dehaine 1971 at Honeywell Bull. Historically, TAB was created as an alternative to wire bonding and finds common use by electronics manufacturers. However speed up of wire bonding methods and development of flip chip - enabling simultaneous bonding of all IOs of the die and easier repaire compared to TAB - have pushed TAB bonding to be used in specific areas like for interconnection of display drivers to the display like liquid crystal display (LCD).", "Engineering,_Manufacturing": 0.9993121624, "qwen": "Yes"}
{"id": "4843630", "revid": "1574590", "url": "https://en.wikipedia.org/wiki?curid=4843630", "title": "Behavioral operations management", "text": "Behavioral operations management (often called behavioral operations) examines and takes into consideration human behaviors and emotions when facing complex decision problems. It relates to the behavioral aspects of the use of operations research and operations management. In particular, it focuses on understanding behavior in, with and beyond models. The general purpose is to make better use and improve the use of operations theories and practice, so that the benefits received from the potential improvements to operations approaches in practice, that arise from recent findings in behavioral sciences, are realized. Behavioral operations approaches have heavily influenced supply chain management research among others.\nOverview.\nOperations management involves a wide range of problem–solving skills aiming to help individuals or organizations to make more rational decisions as well as improving their efficiency. However, operations management often assumes that agents involved in the process or operating system, such as employees, consumers and suppliers, make fully rational decisions. Their decisions are not affected by their emotions as well as their surroundings and that they are able to react and distinguish between different types of information. In reality, this is not always true; human behavior has an important role in decision making and worker motivation, and therefore should be considered in the study of operations. This has led to the rise of behavioral operations management, which is defined as the study of impacts that human behavior has on operations, design and business interactions in different organizations. Behavioral operations management aims to understand the decision making of managers and tries to make improvements to the supply chain using the insight obtained. Behavioral operations management includes knowledge from a number of fields, such as economics, behavioral science, psychology and other social sciences. Traditional operations management and behavioral operations management have a common intellectual goal, aiming to make differences in operations outcomes, such as flexibility, efficiency and productivity.\nTheoretical influence.\nHumans have limitations in their ability to collect and react to relevant information. When a decision or conclusion has to be made through complex information, human decision-makers often fail to comply with normative decision theories. Moreover, a person's lifestyle, social interactions and collective behaviors have a clear influence on their decisions.\nCognitive psychology.\nThis is a relatively new branch of psychology which focuses on humans' ability to make decisions, solve problems, learning, attention, memory and forgetting. These are only a few of the practical applications of this science, to some extent it is also related to motivation and emotion. Cognitive psychology is interested in what is happening within the mind when new information is received, how people respond to this information, and how this response affects their behavior and emotions. Cognitive psychology is considered to be one of the dominant theoretical force in behavioral science.\nSocial psychology.\nPeople often react and behave differently when they are put into different social situations. The aim of social psychology is to understand the nature and causes of individual behaviors. It questions or provides an insight of how human behavior relies on the physical environment. Social psychology theories attempt to explain why there are competition between individuals, why it is often the case that individuals or organisations seek to protect and maintain their status, and why it has been observed that individuals and organisations are willing to sacrifice efficiency to achieve their goal of staying at a higher hierarchical position. In addition to status, social psychology also includes people's behavior towards goal setting, feedback and controls, interdependence, and reciprocity.\nOrganizational behavior.\nThe use of psychology in behavioral operations research links to the idea of judging the relationship between people's mental health and wellbeing and their behavior at work. Psychology experts often set up indicators to evaluate how an employee's surroundings, such as working environment and noise, can affect their productivity. Organizational behavior is the study of ways people react or behave when they are organized in groups. The purpose of these studies is to improve business productivity, trying to create a more efficient business organization. Organizational behavior theories are applied towards human resource trying to maximize the output from individual group members. The study of organization behavior can be broken down into different sections, including personality, job satisfaction and reward management, leadership, authority, power and politics.\nMain streams of research.\nThere are four main streams of research that can be considered a part of behavior operations research. These give us an idea of the weakness of the current operations research model and the effectiveness of behavioral operations research in predicting human decisions and reactions when facing different situations.\nSocio-technical view of technology management.\nPhysical technologies can be defined as a socio-technology system, which consists of humans, human activity, spaces, artifacts, tools, and communications media. This theory suggests that social interaction at the workplace is determined by the technology and techniques used at work. Therefore, a change in technology used at work can lead to unexpected consequences. This may include differences in motivation.\nHuman factor engineering.\nHuman factor engineering can be applied to improve workplaces, working systems and products aiming to reduce human errors during operations as well as improving human efficiency, productivity and operational performance. It often involves improvements of large machineries to reduce accidents during work. It is believed that behavior operations research can be related to human factor engineering as systematic errors, which happens very often technology and different machineries, can affect people's decision making and their interaction with the operating system.\nThe bullwhip effect.\nThe bullwhip effect happens along the supply chain as the result of information asymmetry between the organisations involved. The classic scenario is a sudden increase in customer demand as shown in the figure to the right. The sudden demand hike depletes the retailer's stock resulting in lost sales. To avoid this happen in the future, the retailer does not only increase its next order to the wholesaler by the additional customer demand observed in this period, but by a little bit more just to be safe. That is because the retailer knows it takes time for the wholesaler to deliver the larger order. This fear of losing out in future sales is the behavioral component of the inventory problem causing the bullwhip effect. Faced with an unexpectedly larger order by the retailer, the wholesaler will forward an even larger order to the manufacturer. The manufacturer in turn makes a non-reversible decision to increase its production level even more in the nearer future. However, because of the delay in information flow from customers to manufactures, the latter is not aware for several order periods that its production level actually exceeds customer demand considerably. The result of the bullwhip effect in this classic application is an excessive amount of stock held by retailers, wholesalers and manufacturer. The more tiers a supply chain has, the larger the magnitude of the bullwhip effect becomes.\nSystem dynamics models in operations contexts.\nSystem dynamics models in operations contexts focuses on the importance of how components in a system interact with each other as well as providing an overview of the processes that takes place within the system. Behavioral operations research often benefits from the development of comprehensive systems models as they are able to analyse and provide an insight of the operational system. This allows the study of behavioral operations to understand how people in these settings or work conditions think about the context in which they operate. In an operations system, it often involves levers for managers to manipulate the components involved in the system. The uses of these levers are determined by human behaviors and these behaviors include feelings of stress and fear.\nRelated problems.\nNewsvendor problem.\nThe newsvendor model (or newsboy or single-period or perishable) is a mathematical model used in operations management and applied economics to determine optimal level products or services to keep in stock when the demand is unknown. This model is also known as the newsvendor problem by analogy with the situation faced by a newspaper vendor who must make on time stocking decision of how many copies of newspaper to keep in stock when facing uncertain demand. If the newspaper vendor stocks too much, these newspaper may end up worthless by the end of the day as they are no longer up-to-date. However, if the newspaper vendor stocks too little, he misses the opportunity to make more profit and suffers loss of goodwill.\nAssignment problem.\nThe assignment problem is a complex optimization problem. The problem involves number of agents and a number of tasks. The purpose is to assign each agent with a task. All agents are expected or aimed to be allocated in a way that will maximize productivity and efficiency and minimize the total cost of the assignment.\nSecretary problem.\nThe secretary problem can also be called the optimal stopping theory. It focuses heavily on applied probability, statistics and decision theory. The idea behind the secretary problem is that to make the best decisions when there is a pool of different options, other options are unknown, details of other options will only be given if the currently existing option is given up. The problem comes down to the idea of optimal strategy, maximizing the probability of selecting the best option.", "Engineering,_Manufacturing": 0.9683096409, "qwen": "Yes"}
{"id": "7444893", "revid": "1121442046", "url": "https://en.wikipedia.org/wiki?curid=7444893", "title": "Injection molding of liquid silicone rubber", "text": "Injection molding of liquid silicone rubber (LSR) is a process to produce pliable, durable parts in high volume.\nLiquid silicone rubber is a high purity platinum cured silicone with low compression set, good stability and ability to resist extreme temperatures of heat and cold ideally suitable for production of parts, where high quality is required. Due to the thermosetting nature of the material, liquid silicone injection molding requires special treatment, such as intensive distributive mixing, while maintaining the material at a low temperature before it is pushed into the heated cavity and vulcanized.\nChemically, silicone rubber is a family of thermoset elastomers that have a backbone of alternating silicon and oxygen atoms and methyl or vinyl side groups. Silicone rubbers constitute about 30% of the silicone family, making them the largest group of that family. Silicone rubbers maintain their mechanical properties over a wide range of temperatures and the presence of methyl-groups in silicone rubbers makes these materials extremely hydrophobic, making them suitable for electrical surface insulations.\nTypical applications for liquid silicone rubber are products that require high precision such as seals, sealing membranes, electric connectors, multi-pin connectors, infant products where smooth surfaces are desired, such as bottle nipples, medical applications as well as kitchen goods such as baking pans, spatulas, etc. Often, silicone rubber is overmolded onto other parts made of different plastics. For example, a silicone button face might be overmolded onto a Nylon 6,6 housing.\nEquipment.\nIn order for the liquid injection molding process to fully occur, several mechanical components must be in place. Typically, a molding machine requires a metered pumping device in conjunction with an injection unit—a dynamic or static mixer is attached. An integrated system can aid in precision and process efficiency. The critical components of a liquid injection molding machine include:\nInjectors. An injecting device is responsible for pressurizing the liquid silicone to aid in the injection of the material into the pumping section of the machine. Pressure and injection rate can be adjusted at the operator's discretion.\nMetering Units. Metering units pump the two primary liquid materials, the catalyst and the base forming silicone, ensuring that the two materials maintain a constant ratio while being simultaneously released.\nSupply Drums. Supply drums, also called plungers, serve as the primary containers for mixing materials. Both the supply drums and a container of pigment connect to the main pumping system.\nMixers. A static or dynamic mixer combines materials after they exit the metering units. Once combined, pressure is used to drive the mixture into a designated mold.\nNozzle. To facilitate the deposition of the mixture into the mold, a nozzle is used. Often, the nozzle features an automatic shut-off valve to help prevent leaking and overfilling the mold.\nMold Clamp. A mold clamp secures the mold during the injection molding process, and opens the mold upon completion.\nCharacteristics of LSR.\nBiocompatibility: Under extensive testing, liquid silicone rubber has demonstrated superior compatibility with human tissue and body fluids. In comparison to other elastomers, LSR is resistant to bacteria growth and will not stain or corrode other materials. LSR is also tasteless and odorless and can be formulated to comply with stringent FDA requirements. The material can be sterilized via a variety of methods, including steam autoclaving, ethylene oxide (ETO), gamma, e-beam and numerous other techniques, meeting all required approvals such as BfR XV, FDA 21 CFR 177.2600, USP Class VI.\nDurable: LSR parts can withstand extreme temperatures, which makes them an ideal choice for components under the hood of cars and in close proximity to engines. Parts fabricated via liquid silicone rubber injection molding are fire retardant and will not melt.\nChemical resistance: Liquid silicone rubber resists water, oxidation and some chemical solutions such as acids and alkali.\nTemperature resistance: Compared to other elastomers, silicone can withstand a wide range of high/low temperature extremes.\nMechanical properties: LSR has good elongation, high tear and tensile strength, excellent flexibility and a hardness range of 5 to 80 Shore A.\nElectrical properties: LSR has excellent insulating properties, which offer an appealing option for a host of electrical applications. Compared to conventional insulating material, silicone can perform in far higher and lower temperatures.\nTransparency and pigmentation: LSR possesses a natural transparency. This attribute makes it possible to produce colorful, custom, molded products\nInjection molding process.\nLiquid silicone rubbers are supplied in barrels. Because of their low viscosity, these rubbers can be pumped through pipelines and tubes to the vulcanization equipment. The two components are pumped through a static mixer by a metering pump. One of the components contains the catalyst, typically platinum based. A coloring paste as well as other additives can also be added before the material enters the static mixer section. In the static mixer the components are well mixed and are transferred to the cooled metering section of the injection molding machine. The static mixer renders a very homogeneous material that results in products that are not only very consistent throughout the part, but also from part to part. This is in contrast to solid silicone rubber materials that are purchased pre-mixed and partially vulcanized. In contrast, hard silicone rubbers are processed by transfer molding and result in less material consistency and control, leading to higher part variability. Additionally, solid silicone rubber materials are processed at higher temperatures and require longer vulcanization times.\nLiquid silicone has a very low viscosity index and requires perfect seals of the mould cavity in order to guarantee a burr-free finished product.\nAs injections are carried out at high temperature, steel dilation and natural shrinkage of materials must be considered at the design stage of the LSR injection tooling.\nFrom the metering section of the injection molding machine, the compound is pushed through cooled sprue and runner systems into a heated cavity where the vulcanization takes place. The cold runner and general cooling results in no loss of material in the feed lines. The cooling allows production of LSR parts with nearly zero material waste, eliminating trimming operations and yielding significant savings in material cost.\nLiquid silicone rubbers are supplied in a variety of containers, from tubes to 55 gallon drums. Because of their viscous nature, these liquids are pumped at high pressures (500 - 5000 psi) based on the durometer of the material. The raw materials are shipped in two separate containers (known in the industry as a kit) identified as \"A\" and B\" compounds, with the \"B\" side usually containing the catalyst, but may vary based on the brand of silicone used. The two (A and B) compounds must be mixed in a 1 to 1 ratio, usually by way of a static mixer, adding pigment during the mixing process before the curing process begins. Once the two components come together the curing process begins immediately. A chiller supplying cold water to jacketed fittings is typically used to retard the curing process prior to the materials introduction to the mold. A color pigment can be added via a color injector used in conjunction with the material pump (closed loop metering system) before the material enters the static mixer section.\nIn a cold deck scenario, the 1 to 1 mixed compound is pumped through cooled sprue and runner systems into a heated cavity where the vulcanization takes place. The cold runner and general cooling results in minimal loss of material as the injection occurs directly into the part or cavity, saving on overall material costs and using high consistency rubber. The cooling allows production of LSR parts with nearly zero material valve gate waste, however this does not guarantee a \"flash free\" finished part. Molds and tooling are varying in design, execution and cost. A good cold runner is expensive as compared to conventional hot runner tooling, and has the potential to provide a high level of performance.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "7449438", "revid": "39374154", "url": "https://en.wikipedia.org/wiki?curid=7449438", "title": "Micro-loop heat pipe", "text": "A micro-loop heat pipe or MLHP is a miniature loop heat pipe in which the radius of curvature of the liquid meniscus in the evaporator is in the same order of magnitude of the micro grooves' dimensions; or a miniature loop heat pipe which has been fabricated using microfabrication techniques.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "7465720", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=7465720", "title": "Laser peening", "text": "Laser peening (LP), or laser shock peening (LSP), is a surface engineering process used to impart beneficial residual stresses in materials. The deep, high-magnitude compressive residual stresses induced by laser peening increase the resistance of materials to surface-related failures, such as fatigue, fretting fatigue, and stress corrosion cracking. Laser shock peening can also be used to strengthen thin sections, harden surfaces, shape or straighten parts (known as laser peen forming), break up hard materials, compact powdered metals and for other applications where high-pressure, short duration shock waves offer desirable processing results.\nHistory.\nDiscovery and development (1960s).\nInitial scientific discoveries towards modern-day laser peening began in the early 1960s as pulsed-laser technology began to proliferate around the world. In an early investigation of the laser interaction with materials by Gurgen Askaryan and E.M. Moroz, they documented pressure measurements on a targeted surface using a pulsed laser. The pressures observed were much larger than could be created by the force of the laser beam alone. Research into the phenomenon indicated the high-pressure resulted from a momentum impulse generated by material vaporization at the target surface when rapidly heated by the laser pulse. Throughout the 1960s, a number of investigators further defined and modeled the laser beam pulse interaction with materials and the subsequent generation of stress waves. These, and other studies, observed that stress waves in the material were generated from the rapidly expanding plasma created when the pulsed laser beam struck the target. Subsequently, this led to interest in achieving higher pressures to increase the stress wave intensity. To generate higher pressures it was necessary to increase the power density and focus the laser beam (concentrate the energy), requiring that the laser beam-material interaction occur in a vacuum chamber to avoid dielectric breakdown within the beam in air. These constraints limited study of high-intensity pulsed laser–material interactions to a select group of researchers with high-energy pulsed lasers.\nIn the late 1960s a major breakthrough occurred when N.C. Anderholm discovered that much higher plasma pressures could be achieved by confining the expanding plasma against the target surface. Anderholm confined the plasma by placing a quartz overlay, transparent to the laser beam, firmly against the target surface. With the overlay in place, the laser beam passed through the quartz before interacting with the target surface. The rapidly expanding plasma was now confined within the interface between the quartz overlay and the target surface. This method of confining the plasma greatly increased the resulting pressure, generating pressure peaks of , over an order of magnitude greater than unconfined plasma pressure measurements. The significance of Anderholm's discovery to laser peening was the demonstration that pulsed laser–material interactions to develop high-pressure stress waves could be performed in air, not constrained to a vacuum chamber.\nLaser shocking as a metallurgical process (1970s).\nThe beginning of the 1970s saw the first investigations of the effects of pulsed laser irradiation within the target material. L. I. Mirkin observed twinning in ferrite grains in steel under the crater created by laser irradiation in vacuum. S. A. Metz and F. A. Smidt, Jr. irradiated nickel and vanadium foils in air with a pulsed laser at a low power density and observed voids and vacancy loops after annealing the foils, suggesting that a high concentration of vacancies was created by the stress wave. These vacancies subsequently aggregated during post-iradiation annealing into the observed voids in nickel and dislocation loops in vanadium.\nIn 1971, researchers at Battelle Memorial Institute in Columbus, Ohio began investigating whether the laser shocking process could improve metal mechanical properties using a high-energy pulsed laser. In 1972, the first documentation of the beneficial effects of laser shocking metals was published, reporting the strengthening of aluminum tensile specimens using a quartz overlay to confine the plasma. Subsequently, the first patent on laser shock peening was granted to Phillip Mallozzi and Barry Fairand in 1974. Research into the effects and possible applications of laser peening continued throughout the 1970s and early 1980s by Allan Clauer, Barry Fairand, and coworkers, supported by funding from the National Science Foundation, NASA, Army Research Office, U.S. Air Force, and internally by Battelle. This research explored the in-material effects in more depth and demonstrated the creation of deep compressive stresses and the accompanying increase in fatigue and fretting fatigue life achieved by laser peening.\nPractical laser peening (1980s).\nLaser shocking during the initial development stages was severely limited by the laser technology of the time period. The pulsed laser used by Battelle encompassed one large room and required several minutes of recovery time between laser pulses. To become a viable, economical, and practical industrial process, the laser technology had to mature into equipment with a much smaller footprint and be capable of increased laser pulse frequencies. In the early 1980s, Wagner Castings Company located in Decatur, Illinois became interested in laser peening as a process that could potentially increase the fatigue strength of cast iron to compete with steel, but at a lower cost. Laser peening of various cast irons showed modest fatigue life improvement, and these results along with others, convinced them to fund the design and construction of a pre-prototype pulsed laser in 1986 to demonstrate the industrial viability of the process. This laser was completed and demonstrated in 1987. Although the technology had been under investigation and development for about 15 years, few people in industry had heard of it. So, with the completion of the demonstration laser, a major marketing effort was launched by Wagner Castings and Battelle engineers to introduce laser peening to potential industrial markets.\nAlso in the mid 1980s, Remy Fabbro of the Ecole Polytechnique was initiating a laser shock peening program in Paris. He and Jean Fournier of the Peugeot Company visited Battelle in 1986 for an extended discussion of laser shock peening with Allan Clauer. The programs initiated by Fabbro and carried forward in the 1990s and early 2000s by Patrice Peyre, Laurent Berthe, and co-workers have made major contributions, both theoretical and experimental, to the understanding and implementation of laser peening. In 1998, they measured using VISAR (Velocimeter Interferometer System for Any Reflector) pressure loadings in water confinement regime as function of wavelength. They demonstrate the detrimental effect of breakdown in water limiting maximum pressure at the surface of material.\nCreation of an industry (1990s).\nIn the early 1990s, the market was becoming more familiar with the potential of laser peening to increase fatigue life. In 1991, the U.S. Air Force introduced Battelle and Wagner engineers to GE Aviation to discuss the potential application of laser peening to address a foreign object damage (FOD) problem with fan blades in the General Electric F101 engine powering the Rockwell B-1B Lancer Bomber. The resulting tests showed that laser peened fan blades severely notched after laser peening had the same fatigue life as a new blade. After further development, GE Aviation licensed the laser shock peening technology from Battelle, and in 1995, GE Aviation and the U.S. Air Force made the decision to move forward with production development of the technology. GE Aviation began production laser peening of the F101 fan blades in 1998.\nThe demand for industrial laser systems required for GE Aviation to go into production attracted several of the laser shock peening team at Battelle to start LSP Technologies, Inc. in 1995 as the first commercial supplier of laser peening equipment. Led by founder Jeff Dulaney, LSP Technologies designed and built the laser systems for GE Aviation to perform production laser peening of the F101 fan blades. Through the late 1990s and early 2000s, the U.S. Air Force continued to work with LSP Technologies to mature the laser shock peening production capabilities and implement production manufacturing cells.\nIn the mid 1990s, independent of the laser peening developments ongoing in the United States and France, Yuji Sano of the Toshiba Corporation in Japan initiated the development of a laser peening system capable of laser peening welds in nuclear plant pressure vessels to mitigate stress corrosion cracking in these areas. The system used a low-energy pulsed laser operating at a higher pulse frequency than the higher powered lasers. The laser beam was introduced into the pressure vessels through articulated tubes. Because the pressure vessels were filled with water, the process did not require a water overlay over the irradiated surface. However, the beam had to travel some distance through the water, necessitating using a shorter wavelength beam, 532 nm, to minimize dielectric breakdown of the beam in the water, instead of the 1054 nm beam used in the United States and France. Also, it was impractical to consider using an opaque overlay. This process is now known as Laser Peening without Coating (LPwC). It began to be applied to Japanese boiling water and pressurized water reactors in 1999.\nAlso in the 1990s a significant laser peening research group was formed at the Madrid Polytechnic University by José Ocaña. Their work includes both experimental and theoretical studies using low-energy pulsed lasers both without and with an opaque overlay.\nSupplier foundation and industry growth (1990s – 2000s).\nWith the major breakthrough of commercial application of laser peening on the F101 engine to resolve a major operational problem, laser peening attracted attention around the globe. Researchers in many countries and industries undertook investigations to extend understanding of the laser shock peening process and material property effects. As a result, a large volume of research papers and patents were generated in the United States, France, and Japan. In addition to the work being done in these countries and Spain, laser peening programs were initiated in China, Britain, Germany and several other countries. The continuing growth of the technology and its applications led to the appearance of several commercial laser shock peening providers in the early 2000s.\nGE Aviation and LSP Technologies were the first companies performing laser peening commercially, having licensed the technology from Battelle. GE Aviation performed laser peening for its aerospace engine components and LSP Technologies marketed laser shock peening services and equipment to a broader industrial base. In the late 1990s, Metal Improvement Company (MIC is now part of Curtis Wright Surface Technologies) partnered with Lawrence Livermore National Laboratory (LLNL) to develop its own laser peening capabilities. In Japan, Toshiba Corporation expanded the commercial applications of its LPwC system to pressurized water reactors, and in 2002 implemented fiber optic beam delivery to the underwater laser peening head. Toshiba also redesigned the laser and beam delivery into a compact system, enabling the entire system to be inserted into the pressure vessel. This system was ready for commercial use in 2013 MIC developed and adapted laser shock peening for forming the wing shapes on the Boeing 747-8.\nThe growth of industrial suppliers and commercial proof of laser peening technology lead to many companies adopting laser peening technology to solve and prevent problems. Some of the companies who have adopted laser peening include: GE, Rolls-Royce, Siemens, Boeing, Pratt & Whitney, and others.\nIn the 1990s and continuing through present day, laser peening developments have targeted decreasing costs and increasing throughput to reach markets outside of high-cost low-volume components. High costs in the laser peening process were previously attributable to laser system complexity, processing rates, manual labor and overlay applications. Numerous ongoing advancements addressing these challenges have reduced laser peening costs dramatically: laser peening systems are designed to handle robust operations; pulse rates of laser systems are increasing; routine labor operations are increasingly automated; application of overlays are automated in many cases. These reduced operational costs of laser peening have made it a valuable tool for solving an extended range of fatigue and related applications.\nProcess description.\nLaser peening uses the dynamic mechanical effects of a shock wave imparted by a laser to modify the surface of a target material. It does not utilize thermal effects. Fundamentally, laser peening can be accomplished with only two components: a transparent overlay and a high-energy pulsed laser system. The transparent overlay confines the plasma formed at the target surface by the laser beam. It is also often beneficial to use a thin overlay, opaque to the laser beam, between the water overlay and the target surface. This opaque overlay can provide either or each of three benefits: protect the target surface from potentially detrimental thermal effects from the laser beam, provide a consistent surface for the laser beam-material interaction and, if the overlay impedance is less than that of the target surface, increase the magnitude of the shock wave entering the target. However, there are situations where an opaque overlay is not used; in the Toshiba process, LPwC, or where the tradeoff between decreased cost and possibly somewhat lowered surface residual stress allows superficial grinding or honing after laser peening to remove the thin thermally effected layer.\nThe laser peening process originated with high-energy Nd-glass lasers producing pulse energies up to 50 J (more commonly 5 to 40 J) with pulse durations of 8 to 25 ns. Laser spot diameters on target are typically in the range of 2 to 7 mm. The processing sequence begins by applying the opaque overlay on the workpiece or target surface. Commonly used opaque overlay materials are black or aluminum tape, paint or a proprietary liquid, RapidCoater. The tape or paint is generally applied over the entire area to be processed, while the RapidCoater is applied over each laser spot just before triggering the laser pulse. After application of the opaque overlay, the transparent overlay is placed over it. The transparent overlay used in production processing is water; it is cheap, easily applied, readily conforms to most complex surface geometries, and is easily removed. It is applied to the surface just before triggering the laser pulse. Quartz or glass overlays produce much higher pressures than water, but are limited to flat surfaces, must be replaced after each shot and would be difficult to handle in a production setting. Clear tape may be used, but requires labor to apply and is difficult to conform to complex surface features. The transparent overlay allows the laser beam to pass through it without appreciable absorption of the laser energy or dielectric breakdown. When the laser is triggered, the beam passes through the transparent overlay and strikes the opaque overlay, immediately vaporizing a thin layer of the overlay material. This vapor is trapped in the interface between the transparent and opaque overlays. The continued delivery of energy during the laser pulse rapidly heats and ionizes the vapor, converting it into a rapidly expanding plasma. The rising pressure exerted on the opaque overlay surface by the expanding plasma enters the target surface as a high-amplitude stress wave or shock wave. Without a transparent overlay, the unconfined plasma plume moves away from the surface and the peak pressure is considerably lower. If the amplitude of the shock wave is above the Hugoniot Elastic Limit (HEL), i.e., the dynamic yield strength, of the target, the material plastically deforms during passage of the shock wave. The magnitude of the plastic strain decreases with distance from the surface as the peak pressure of the shock wave attenuates, i.e., decreases, and becomes zero when the peak pressure falls below the HEL. After the shock wave passes, the residual plastic strain creates a compressive residual stress gradient below the target surface, highest at or immediately below the surface and decreasing with depth. By varying the laser power density, pulse duration, and number of successive shots on an area, a range of surface compressive stress magnitudes and depths can be achieved. The magnitude of surface stresses are comparable to shot peening, but the depths are much greater, ranging up to 5 mm when using multiple shots on a spot. Generally spot densities of about 10 spots/cm2 to 40 spots/cm2 are applied. The compressive stress depth achieved with the most common processing parameters ranges from deep. The deep compressive stresses are due to the shock wave peak pressure being maintained above the HEL to greater depths than for other peening technologies.\nThere may be instances where it is cost effective not to apply the opaque overlay and laser peen the bare surface of the work piece directly. When laser peening a bare, metallic surface a thin, micrometer-range, layer of surface material is vaporized. The rapid rise in temperature causes surface melting to a depth dependent on pulse energy and duration, and target melting point. On aluminum alloys this depth is nominally 10–20 μm, but on steels and other higher melting point alloys the depths may be just a few micrometers. Due to the short duration of the pulse, the in-depth heating of the surface is limited to a few tens of micrometers due to the rapid quenching effect of the cold substrate. Some superficial surface staining of the work piece may occur, typically from oxidation products. These detrimental effects of bare surface processing, both aesthetic and metallurgical, can be removed after laser peening by light grinding or honing. With an opaque overlay in place, the target surface experiences temperature rises of less than on a nanosecond time scale.\nLaser pulses are generally applied sequentially on the target to treat areas larger than the laser spot size. Laser pulse shapes are customizable to circular, elliptical, square, and other profiles to provide the most convenient and efficient processing conditions. The spot size applied depends on a number of factors that include material HEL, laser system characteristics and other processing factors. The area to be laser peened is usually determined by the part geometry, the extent of the fatigue critical area and considerations of moving the compensating tensile stresses out of this area.\nThe more recently developed laser peening process, the Toshiba LPwC process, varies in significant ways from the process described above. The LPwC process utilizes low-energy high-frequency producing pulse energies of and pulse durations of , using spot sizes diameter. Because the process originally was intended to operate in large water-filled vessels, the wave frequency was doubled to halve the wavelength to 532 nm. The shorter wavelength decreases the absorption of beam energy while traveling through water to the target. Due to access constraints, no opaque overlay is applied to the target surface. This factor, combined with the small spot size, requires many shots to achieve a significant surface compressive stress and depths of 1 mm. The first layers applied produce a tensile surface stress due to surface melting, although a compressive stress is developed below the melt layer. However, as more layers are added, the increasing subsurface compressive stress \"bleeds\" back through the melted surface layer to produce the desired surface compressive stress. Depending on material properties and the desired compressive stresses, generally about 18 spots/mm2 to 70 spots/mm2 or greater spot densities are applied, about 100 times the spot densities of the high-pulse-energy process. The effects of the higher spot densities on processing times are compensated for in part by the higher pulse frequency, 60 Hz, of the low-energy lasers. Newer generations of these laser systems are projected to operate at higher frequencies. This low-energy process achieves compressive residual stress magnitudes and depths equivalent to the high-energy process with nominal depths of . However, the smaller spot size will not permit depths deeper than this.\nQuality systems for laser peening.\nThe laser peening process using computer control is described in AMS 2546. Like many other surface enhancement technologies, direct measuring of the results of the process on the workpiece during processing is not practical. Therefore, the process parameters of pulse energy and duration, water and opaque overlays are closely monitored during processing. Other quality control systems are also available that rely on pressure measurements such as electromagnetic acoustic transducers (EMAT), Velocity Interferometer System for Any Reflector (VISAR) and PVDF gauges, and plasma radiometers. Almen strips are also used, but they function as a comparison tool and do not provide a definitive measure of laser peening intensity. The resultant residual stresses imparted by the laser peening process are routinely measured by industry using x-ray diffraction techniques for the purposes of process optimization and quality assurance.\nLaser peening systems.\nThe initial laser systems used during the development of laser peening were large research lasers providing high-energy pulses at very low pulse frequencies. Since the mid-late 1990s, lasers designed specifically for laser peening featured steadily smaller size and higher pulse frequencies, both of these more desirable for production environments. The laser peening systems include both rod laser systems and a slab laser system. The rod laser systems can be separated roughly into three primary groups, recognizing that there is some overlap between them: (1) high-energy low-repetition rate lasers operating typically at 10–40 J per pulse with 8–25 ns pulse length at nominally 0.5–1 Hz rep rate, nominal spot sizes of 2 to 8 mm; (2) intermediate energy, intermediate repetition rate lasers operating at 3–10 J with 10–20 ns pulse width at 10 Hz rep rate, nominal spot sizes of 1–4 mm; (3) low-energy, high-repetition rate lasers operating at per pulse with ≤10 ns pulse length at 60+ Hz rep rate, spot size. The slab laser system operates in the range of 10–25 J per pulse with 8–25 ns pulse duration at 3–5 Hz rep rate, nominal spot sizes of 2–5 mm. The commercial systems include rod lasers represented by all three groups and the slab laser system.\nFor each laser peening system the output beam from the laser is directed into a laser peening cell containing the work pieces or parts to be processed. The peening cell contains the parts handling system and provides the safe environment necessary for efficient commercial laser peening. The parts to be processed are usually introduced into the cell in batches. The parts are then picked and placed in the beam path by robots or other customized parts handling systems. Within the work cell, the beam is directed to the surface of the work piece via an optical chain of mirrors and/or lenses. If tape is used, it is applied before the part enters the work cell, whereas water or RapidCoater overlays are applied within the cell individually for each spot. The workpiece, or sometimes the laser beam, is repositioned for each shot as necessary via a robot or other parts handling system. When the selected areas on each part have been processed, the batch is replaced in the work cell by another.\nProcess effect.\nThe shockwave generated coldwork (plastic strain) in the workpiece material creates compressive and tensile residual stresses to maintain an equilibrium state of the material. These residual stresses are compressive at the workpiece surface and gradually fade into low tensile stresses below and surrounding the laser peened area. The cold work also work hardens the surface layer. The compressive residual stresses, and to a lesser extent, the cold work, from laser peening have been shown to prevent and mitigate high cycle fatigue (HCF), low cycle fatigue (LCF), stress corrosion cracking, fretting fatigue, and, to some degree, wear and corrosion pitting. It is outstanding at mitigating foreign object damage in turbine blades.\nThe plastic strain introduced by laser peening is much lower than that introduced by other impact peening technologies. As a result, the residual plastic strain has much greater thermal stability than the more heavily cold worked microstructures. This enables the laser peened compressive stresses to be retained at higher operating temperatures during long exposures than is the case for the other technologies. Among the applications benefiting from this are gas turbine fan and compressor blades and nuclear plant components.\nBy enhancing material performance, laser peening enables more-efficient designs that reduce weight, extend component lifetimes, and increase performance. In the future, it is anticipated that laser peening will be incorporated into the design of fatigue critical components to achieve longer life, lighter weight, and perhaps a simpler design to manufacture.\nOther applications of laser peening technologies.\nOriginally, the use of laser-induced shock waves on metals to achieve property or functional benefits was referred to as laser shock processing, a broader, more inclusive term. As it happened, laser peening was the first commercial aspect of laser shock processing. However, laser-induced shock waves have found uses in other industrial applications outside of surface enhancement technologies.\nOne application is for metal shaping or forming. By selectively laser shocking areas on the surface of metal sheets or plates, or smaller items such as airfoils, the associated compressive residual stresses cause the material to flex in a controllable manner. In this way a particular shape can be imparted to a component, or a distorted component might be brought back into the desired shape. Thus, this process is capable of bringing manufactured parts back into design tolerance limits and form shaping thin section parts.\nAnother variation is to use the shock wave for spallation testing of materials. This application is based on the behavior of shockwaves to reflect from the rear free surface of a work piece as a tensile wave. Depending on the material properties and the shock wave characteristics, the reflected tensile wave may be strong enough to form microcracks or voids near the back surface, or actually \"blow-off\" or spall material from the back surface. This approach has some value for testing ballistic materials.\nUse of laser shocks to measure the bond strength of coatings on metals has been developed over a period of years in France called LASAT for Laser Adhesion Test. This application is also based on the behavior of shockwaves to reflect from the rear free surface of a work piece as a tensile wave. If the back surface is coated with an adherent coating, the tensile wave can be tailored to fracture the bond upon reflection from the surface. By controlling the characteristics of the shock wave, the bond strength of the coating can be measured, or alternatively, determined in a comparative sense.\nCareful tailoring of the shockwave shape and intensity has also enabled the inspection of bonded composite structures via laser shocking. The technology, termed Laser Bond Inspection initiates a shockwave that reflects off the backside of a bonded structure and returns as a tensile wave. As the tensile wave passes back through the adhesive bond, depending on the strength of the bond and the peak tensile stress of the stress wave, the tensile wave will either pass through the bond or rupture it. By controlling the pressure of the tensile wave this procedure is capable of reliably locally testing adhesion strength between bonded joints. This technology is most often found in application to bonded fiber composite material structures but has also been shown to be successful in evaluating bonds between metal-composite material. Fundamental issues are also studied to characterize and quantify the effect of shock wave produced by laser inside these complex materials.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "25215836", "revid": "1166246748", "url": "https://en.wikipedia.org/wiki?curid=25215836", "title": "Generative design", "text": "Generative design is an iterative design process that generates outputs that meet specified constraints to varying degrees. In a second phase, designers can then provide feedback to the generator that explores the feasible region by selecting preferred outputs or changing input parameters for future iterations. Either or both phases can be done by humans or software. One method is to use a generative adversarial network, which is a pair of neural networks. The first generates a trial output. The second provides feedback for the next iteration.\nThe output can be items such as images, sounds, architectural models, animation, and industrial parts. It is used in design fields such as art, architecture, communication design, and product design.\nComputers can explore orders of magnitude more permutations, exploring the interactions of the enormous numbers of design elements in small increments.It mimics nature’s evolutionary approach to design through genetic variation and selection. These techniques are available even for designers with little programming experience. It is supported by commercially available CAD packages. Tools leveraging generative design as a foundation are available.\nCompared with traditional top-down design approaches, generative design addresses design problems by using a bottom-up paradigm. The solution itself then evolves to a good, if not optimal, solution.\nGenerative design involves rule definition and result analysis which are integrated with the design process. By defining parameters and rules, the generative approach is able to provide optimized solution for both structural stability and aesthetics. Possible design algorithms include cellular automata, shape grammar, genetic algorithm, space syntax, and most recently, artificial neural network. Due to the high complexity of the solution generated, rule-based computational tools, such as finite element method and topology optimisation, are more preferable to evaluate and optimise the generated solution. The iterative process provided by computer software enables the trial-and-error approach in design, and involves architects interfering with the optimisation process.\nThe software then begins iterating, changing things a bit at a time, much like random mutations try out new combinations of animal DNA, and testing it against the necessary performance targets, much like life tests its DNA mutations. Over millions of generations, the software adds a little metal here, removes a little there, and checks if the part is stronger or weaker, lighter or heavier than its predecessors.\nWithin a surprisingly short time (a couple of hours, if given access to high-powered cloud processing), it comes back with shapes humans could never have directly designed. But they're strikingly similar to the work of nature; where there's more stress to be dealt with, they gradually become thicker. Where there's less stress, they get thinner. Support structures waste away where they're not needed, and tend to line up with the load path. In short, they start looking weirdly bony and organic.\nApplications.\nArchitecture and Industrial Design.\nGenerative Design is a morphogenetic process using algorithms structured as not-linear systems for endless unique and unrepeatable results performed by an idea-code, as in Nature. (C.Soddu 1992) url=https://generativedesign.com\nArchitecture.\nGenerative design has been applied in architecture. Architectural design has long been regarded as a wicked problem. The advantage of using generative design as a design tool is that it does not construct fixed geometries, but take a set of design rules that can generate an infinite set of possible design solutions. The generated design solutions can be more sensitive, responsive, and adaptive to the wicked problem.\nHistorical precedent work includes Antoni Gaudí's Sagrada Família, which used rule-based geometrical forms for structures, and Buckminster Fuller's Montreal Biosphere where the rules to generate individual components is designed, rather than the final product.\nMore recent generative design cases includes Foster and Partners' Queen Elizabeth II Great Court, where the tessellated glass roof was designed using a geometric schema to define hierarchical relationships, and then the generated solution was optimized based on geometrical and structural requirement.\nComponent design.\nNASA has begun using generative design in its parts. What they call \"evolved structures\" weigh less and stress concentrations common in human designs. Weights go down by as much as two thirds, while stress factors are nearly 10 times lower. Such parts are often made via additive manufacturing. Design and manufacturing can take as little as one week. Parts appear in projects such as the Mars Sample Return mission, space telescopes, weather monitors, planetary instruments, and balloon observatories.", "Engineering,_Manufacturing": 0.9975808263, "qwen": "Yes"}
{"id": "43035587", "revid": "10289486", "url": "https://en.wikipedia.org/wiki?curid=43035587", "title": "Rotating disk viscometer", "text": "The Rotating disk viscometer, or \"Mooney Machine\" as it is sometimes referred to in the rubber industry, is the standard viscometer for measuring material viscosity and scorch time for rubber before vulcanization. It was developed in the 1930s by Melvin Mooney. For a specific temperature, scorch time describes how long it will take the material to vulcanize. For example, a scorch time at ambient temperature indicates the rubber will be able to remain unvulcanized at room temperature for an extended period of time.\nOverview.\nThe Mooney machine itself consists of a cylindrical, serrated, metal disk designed to hold a material sample without slippage during rotation. This disk is surrounded by a die chamber where the rubber is pressed with 2500 pounds of force. The rubber is then warmed for two minutes. Next, the serrated disk is rotated, in one direction only, at a speed of 2 revolutions per minute, while the torque required to rotate the disk is recorded. The torque decrease per time can be directly related to viscosity.\nAs the material further warms during initial rotation of the serrated disk and the rubber begins to shear, the viscosity lowers and torque required decreases. Eventually, the torque will reach an inflection point, where the rubber begins to vulcanize and torque begins increasing. A shear pin on the machine prevents damage as the testing material stiffens. Comparing the torque versus time curves for different materials allows direct correlation of material viscosity and scorch time.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "60011838", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=60011838", "title": "Nanotech metallurgy", "text": "Nanotech metallurgy (also called nanotechnology enabled metallurgy, or nanometallurgy) is an emerging interdisciplinary domain of materials science and engineering (especially metallurgy), manufacturing, and nanoscience and engineering to study how nanophases (both ex situ and in situ) can be applied to significantly improve the processing/manufacturing, micro/nano-structures, and physical/chemical/mechanical behaviors of metals and alloys. This definition was first proposed by Xiaochun Li at the University of California, Los Angeles in 2018.\nHigh performance metals and alloys offer potential to improve energy efficiency and system performance. While conventional metallurgical methods have reached certain limits, nanotech metallurgy has the potential to break the traditional barriers in the metals processing and manufacturing technologies. It has a wider scientific and technological reach beyond the concept of metal matrix nanocomposites (MMNCs), as the study of MMNCs normally focuses on how nanoparticles (generally of high volume fractions) are used to tune material properties only. With the development of more scalable methods of nanophase synthesis, incorporation, and dispersion for mass manufacturing, the metals and alloys produced by nanotech metallurgy are becoming more and more economical. Recently the discovery of a nanoparticle self-dispersion and stabilization mechanism in molten metals gives a scientific and technical foundation for scalable manufacturing in nanotech metallurgy.\nFundamental concepts.\nNanotech metallurgy covers research areas such as nanophase effects on processing/manufacturing, materials properties (e.g. mechanical, physical and chemical properties), synthesis and production of nanophases (both in situ and ex situ), interaction between nanophases and molten metal, solidification, and thermomechanical processing of metals containing nanophases.\nNanophase effects on metals processing and manufacturing.\nNanophases can be effectively used to tune microstructures of metals and alloys during solidification and thermomechanical deformation, to control recrystallization at elevated temperatures, and to break traditional metallurgical barriers, thus creating exciting new spaces in processing and manufacturing, such as in casting, thermoplastic deformation, welding/joining, heat treatment, and machining, etc..\nNanophase effects on materials properties.\nNanophases have significant effects on mechanical, physical and chemical properties of metals. As compared with conventional metal matrix composites (MMCs) that are reinforced by micro-scale phases, the addition of nanophases is promising to overcome many disadvantages of MMCs such as poor ductility, machinability and low fracture toughness. For example, a super-strong but lightweight metal with extremely high specific strength and modulus was developed by disperse ceramic silicon carbide nanoparticles in magnesium.\nNanophases synthesis and production.\nNanotech metallurgy covers the synthesis, production and incorporation of nanophases (e.g. nanoparticles, nanowires, nanosheets, carbon nanotubes (CNTs), graphene, etc.). To utilize the cutting edge nanotechnology to metallurgy, the scalability and cost of the nanophases are the major concerning factors to evaluate the feasibility. It is worth to mention that, with the rapid development of nanophase synthesis, production, incorporation, and dispersion, the cost of nanophases are becoming increasingly economical for metallurgy. Recent studies (e.g. molten salt reaction, in-situ reaction etc.) on molten salt based nanophase synthesis and incorporation indicatefurther ways to reduce the cost of nanophases and open up wider applications\nNanoparticles and molten metal interactions.\nThe interactions between nanophases and molten metal include wetting, incorporation, mixing and dispersion.\nSolidification of metals containing nanophases.\nResearchers have utilized the nanoparticles to refine the grain for different alloys(e.g. Al alloy, Mg alloy, etc.) during solidification including casting, welding, 3D printing, etc. They can modify the grain size by serving as heterogeneous nucleation site or inhibiting grain growth during solidification. Nanoparticles can help to refine the secondary phase as well.\nApplications.\nNanotech metallurgy can be applied to a wide range applications including automobile, sports, biomedical, electrical and electronics, aerospace, and defense s, etc.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "44094917", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=44094917", "title": "Schoenflies displacement", "text": "Schoenflies (or Schönflies) displacement (or motion) named after Arthur Moritz Schoenflies is a rigid body motion consisting of linear motion in three dimensional space plus one orientation around an axis with fixed direction. In robotic manipulation this is a common motion as many pick and place operations require moving an object from one plane and placing it with a different orientation onto another parallel plane (\"e.g.\", placement of components on a circuit board). These robots are commonly called Schoenflies-motion generators.\nBecause the SCARA manipulator was one of the first manipulators providing similar motion, this is often referred to as SCARA-type motion. Today, many robotic manipulators, including some with parallel kinematic architecture, are used in industry for applications ranging from the manufacture of electronics to food processing and packaging industry.", "Engineering,_Manufacturing": 0.9993891716, "qwen": "Yes"}
{"id": "44111566", "revid": "7183365", "url": "https://en.wikipedia.org/wiki?curid=44111566", "title": "Robocasting", "text": "Robocasting (also known as robotic material extrusion) is an additive manufacturing technique analogous to Direct Ink Writing and other extrusion-based 3D-printing techniques in which a filament of a paste-like material is extruded from a small nozzle while the nozzle is moved across a platform. The object is thus built by printing the required shape layer by layer. The technique was first developed in the United States in 1996 as a method to allow geometrically complex ceramic green bodies to be produced by additive manufacturing. In robocasting, a 3D CAD model is divided up into layers in a similar manner to other additive manufacturing techniques. The material (typically a ceramic slurry) is then extruded through a small nozzle as the nozzle's position is controlled, drawing out the shape of each layer of the CAD model. The material exits the nozzle in a liquid-like state but retains its shape immediately, exploiting the rheological property of shear thinning. It is distinct from fused deposition modelling as it does not rely on the solidification or drying to retain its shape after extrusion.\nProcess.\nRobocasting begins with a software process. One method is importing an STL file and slicing that shape into layers of similar thickness to the nozzle diameter. The part is produced by extruding a continuous filament of material in the shape required to fill the first layer. Next, either the stage is moved down or the nozzle is moved up and the next layer is deposited in the required pattern. This is repeated until the 3D part is complete. Numerically controlled mechanisms are typically used to move the nozzle in a calculated tool-path generated by a computer-aided manufacturing (CAM) software package. Stepper motors or servo motors are usually employed to move the nozzle with precision as fine as nanometers.\nThe part is typically very fragile and soft at this point. Drying, debinding and sintering usually follow to give the part the desired mechanical properties.\nDepending on the material composition, printing speed and printing environment, robocasting can typically deal with moderate overhangs and large spanning regions many times the filament diameter in length, where the structure is unsupported from below. This allows intricate periodic 3D scaffolds to be printed with ease, a capability which is not possessed by other additive manufacturing techniques. These parts have shown extensive promise in fields of photonic crystals, bone transplants, catalyst supports, and filters. Furthermore, supporting structures can also be printed from a \"fugitive material\" which is easily removed. This allows almost any shape to be printed in any orientation.\nMechanical behavior.\nOne key advantage of the robocasting additive manufacturing technique is its ability to utilize a wide range of feedstock “inks,” as shear-thinning ability is the only inherently required material property. As such, robocasting has seen diverse application among many disparate materials classes such as metallic foams, pre-ceramic polymers, and biological tissues. This allows for a wide range of mechanical characteristics to be accessible through this technique, with additional tailoring possible through the use of ink fillers and varying extrusion parameters.\nFiller effects.\nMicro- and nano-scale filler materials are commonly used to create composite feedstocks for robocasting and are available in a wide range of compositions, with morphologies typically falling into the broad categories of spheres, platelets, and filaments/tubes. Both composition and morphology play significant roles in the mechanical characteristics imparted by the filler. For example, the inclusion of stiff boron nitride nanobarbs within epoxy feedstock has been demonstrated to anisotropically increase overall composite strength and stiffness along the direction of fiber orientation due to their shape asymmetry, while the inclusion of hollow glass microspheres within the same epoxy feedstock has been demonstrated to isotropically improve specific strength by significantly reducing total density of the composite.\nIn addition to shape, differing size regimes within fillers of the same morphology have been demonstrated to yield significant changes in mechanical properties. For epoxy-carbon fiber composite systems of identical composition, flexural strength has been shown to generally decrease with decreasing fiber length. However, shorter fibers have also been demonstrated to produce better overall printing behavior during the robocasting process as increasing length also increases the likelihood of jamming within the extruder; higher print fidelity as seen for the shorter fibers generally results in greater reproducibility of mechanical behavior. In addition, very long fibers have exhibited a tendency to break during extrusion, essentially imparting a de facto size cap on filament-type fillers used in robocasting.\nExtrusion effects.\nExtrusion phenomena inherently tied into the robocasting technique have been shown to have appreciable effects on the mechanical behavior of resulting parts. One of the most significant is the alignment of filler materials within composite feedstocks during deposition, which is enhanced as filler anisotropy increases. This alignment phenomenon also becomes more pronounced with decreasing nozzle diameter and increasing ink deposition speed, as these factors increase the effective shearing experienced by fillers suspended within the feedstock in accordance with Jeffrey-Hamel flow theory. Fillers are thus driven to align parallel to the extrusion pathway, imparting significant anisotropic character within the finished part. This anisotropy can be further enhanced by prescribing extrusion pathways that remain parallel throughout the manufacturing process; conversely, prescribing extrusion pathways that exhibit differing orientations, such as 90° “logpile” rotation between layers, can mitigate this effect.\nSelection of deposition pathing can also be exploited to alter mechanical characteristics of robocasting products, such as in the case of non-dense and graded components. The creation of open lattice-type structures via robocasting is widespread and enables optimization of specific strength and stiffness by reducing the cross-sectional footprint of a given feedstock material while retaining much of its bulk mechanical integrity. In addition, the creation of unique deposition pathing via finite element analysis of a desired structure can generate dynamically-graded geometries optimized for specific applications.\nApplications.\nThe technique can produce non-dense ceramic bodies which can be fragile and must be sintered before they can be used for most applications, analogous to a wet clay ceramic pot before being fired. A wide variety of different geometries can be formed from the technique, from solid monolithic parts to intricate microscale \"scaffolds\", and tailored composite materials. A heavily-researched application for robocasting is in the production of biologically compatible tissue implants. \"Woodpile\" stacked lattice structures can be formed quite easily which allow bone and other tissues in the human body to grow and eventually replace the transplant. With various medical scanning techniques the precise shape of the missing tissue was established and input into 3D modelling software and printed. Calcium phosphate glasses and hydroxyapatite have been extensively explored as candidate materials due to their biocompatibility and structural similarity to bone.\nOther potential applications include the production of specific high surface area structures, such as catalyst beds or fuel cell electrolytes. Advanced metal matrix- and ceramic matrix- load bearing composites can be formed by infiltrating woodpile bodies with molten glasses, alloys or slurries.\nRobocasting has also been used to deposit polymer and sol-gel inks through much finer nozzle diameters (less than 2 μm) than is possible with ceramic inks.", "Engineering,_Manufacturing": 1.0000038147, "qwen": "Yes"}
{"id": "6768880", "revid": "5042921", "url": "https://en.wikipedia.org/wiki?curid=6768880", "title": "Boriding", "text": "Boriding, also called boronizing, is the process by which boron is added to a metal or alloy. It is a type of surface hardening. In this process boron atoms are diffused into the surface of a metal component. The resulting surface contains metal borides, such as iron borides, nickel borides, and cobalt borides, As pure materials, these borides have extremely high hardness and wear resistance. Their favorable properties are manifested even when they are a small fraction of the bulk solid. Boronized metal parts are extremely wear resistant and will often last two to five times longer than components treated with conventional heat treatments such as hardening, carburizing, nitriding, nitrocarburizing or induction hardening. Most borided steel surfaces will have iron boride layer hardnesses ranging from 1200-1600 HV. Nickel-based superalloys such as Inconel and Hastalloys will typically have nickel boride layer hardnesses of 1700-2300 HV.\nMethods.\nBoriding can be achieved in several ways, but commonly the metal piece is packed with a boriding mixture and heating at 900 °C. Typical boriding mixture consists of boron carbide powder diluted with other refractory materials. The process converts some of the Fe to iron boride, consisting of two phases: FeB concentrated near the surface, and diiron boride (Fe2B). Boride layer depths can range from 0.001 - 0.015 inches (25.4 - 38 µm) depending on base material selection and treatment.\nMaterials.\nIt is often used on steel, but is applicable to a variety of alloys and cermet materials. A wide range of materials suitable for treatment including plain carbon steels, alloy steels, tool steels, nickel-based super alloys, cobalt alloys, and stellite.\nProperties conferred.\nBoriding gives the material the following desirable properties: wear resistance, improved hardness (1300-2000HV is possible), thermal stability, resistance to corrosion by acids, reduced coefficient of friction, and increased galling/cold-welding resistance. It is possible to combine boriding with other heat treatments such as carburizing, hardening or induction hardening to create deeper wear layers or high core hardness.", "Engineering,_Manufacturing": 0.9995575547, "qwen": "Yes"}
{"id": "6771511", "revid": "2304267", "url": "https://en.wikipedia.org/wiki?curid=6771511", "title": "Jewelry wire", "text": "Jewelry wire is wire, usually copper, brass, nickel, aluminium, silver, or gold, used in jewelry making. \nWire is defined today as a single, usually cylindrical, elongated strand of drawn metal. However, when wire was first invented over 2,000 years BC, it was made from gold nuggets pounded into flat sheets, which were then cut into strips. The strips were twisted and then rolled into the round shape we call wire. This early wire, which was used in making jewelry, can be distinguished from modern wire by the spiral line along the wire created by the edges of the sheet. \nModern wire is manufactured in a different process that was discovered in Ancient Rome. In this process, a solid metal cylinder is pulled through a draw plate with holes of a defined size. Thinner sizes of wire are made by pulling wire through successively smaller holes in the draw plate until the desired size is reached. \nWhen wire was first invented, its use was limited to making jewelry. Today, wire is used extensively in many applications including fencing, the electronics industry, electrical distribution, and the making of wire wrapped jewelry.\nWire hardness.\nAll metals have a property called hardness, which is the property of the metal that resists bending. Soft metals are pliable and easy to bend while hard metals are stiff and hard to bend. The hardness of metals can be changed by annealing with heat treatment, or by work hardening a wire by bending it.\nMost modern manufacturers of jewelry wire make the wire with a defined hardness, generally a hardness of 0, 1, 2, 3, or 4. Historically, these numbers were associated with the number of times that the wire was pulled through a draw plate, becoming harder or stiffer each time it was drawn through the drawplate. A hardness of 0 meant that the wire had been drawn through only once and was as soft and as pliable as possible. A hardness of 4 meant that the wire had been drawn through five or more times and the wire was as stiff and as hard as possible. Most jewelry wire that is sold now is designated dead soft, half-hard, or hard, where dead soft is wire that is manufactured with a hardness of 0, half-hard is wire manufactured with a hardness of 2, and fully hardened wire is wire with a hardness of 4. \nDead soft wire is extremely soft and pliable. It can be easily bent and is excellent for making rounded shapes such as spirals. It is also excellent for wrapping wire around beads to make them look as though they are encased. The disadvantage of using soft wire is that the finished piece can be bent out of shape if not properly handled. \nHalf-hard wire is slightly stiffer than dead soft wire. Half-hard wire is excellent for making tight, angular bends, for making loops in wire, and for wrapping wire around itself. However, it is not very useful for making spirals. Finished pieces made with half-hard wire are usually more permanent than pieces made with soft wire. \nHard wire is very stiff and tends to spring back after being bent, making it harder to work with when using a jig; it cannot be used to make a spiral. Pieces made with hard wire have the advantage that they are not easily accidentally deformed.\nAs in many things, no single wire is perfect for all applications. Soft wire is easy to bend and shape, but the finished product may be bent out of shape if squeezed. Hard wire is difficult to bend but makes permanent shapes. Half-hard wire is a compromise between the two. Wire-wrapped jewelry can be made by wire which is initially soft, simplifying fabrication, but later hardened by hammering or by work hardening.\nWire shape.\nHistorically, all wire was round. Advances in technology now allow the manufacture of jewelry wire with different cross-sectional shapes, including circular, square, and half-round. Half round wire is often wrapped around other pieces of wire to connect them. Square wire is used for its appearance: the corners of the square add interest to the finished jewelry. Square wire can be twisted to create interesting visual effects.\nWire size.\nFor jewelry applications, gauges 12–28 are most common. The size of wire is defined by one of two measuring systems. The American wire gauge (AWG) and the Standard wire gauge (SWG) systems. AWG is usually, but not always the standard for defining the sizes of wire used in the United States, and SWG is usually, but not always the standard wire sizing system used in the United Kingdom. With both the AWG and SWG systems, the larger the number, the smaller the gauge. For example: 2-gauge wire is large (like a pencil) and 30-gauge wire is fine, like thread. In much of the world wire diameter is often expressed in millimeters. \nFor making jump rings, 10- to 18-gauge wire (2.5 to 1.3 mm) is used. Bracelet and necklace wire components are generally made out of wire that is 16-, 18- or 20-gauge (1.3 to 0.8 mm). Earring wires are usually made out of 18- or 20-gauge wire (1.0 to 0.8 mm). When making wire wrapped jewelry, these components are connected to one another with wire that is generally 20- to 26-gauge (0.8 to 0.4 mm). Frequently the connections between wire components will include a bead on the wire connector in a technique called a wire-wrapped loop. Most glass beads (but not all) are manufactured with a hole that is 1 mm in size. This will accommodate 20-gauge wire, but will probably not accommodate 18-gauge wire. Some glass beads, almost all freshwater pearls and some gemstone beads will have smaller holes and will require the use of wire thinner than 20-gauge. (The largest wire that can go through the beads is generally chosen. Beads and gemstones are much harder than the wire, and will over time saw into the wire; so thicker wire will last longer.) \nThick wire, of 16-gauge and heavier, is harder to bend and requires more expert handling. Hammering wire with a plastic or rawhide mallet will harden wire without changing its shape. Hammering wire with a metal jeweler's hammer (chasing hammer) will harden and flatten wire.\nFor thickness of body jewelry sizes, gauges of all sizes can be found, notably with stretching.", "Engineering,_Manufacturing": 0.6878256798, "qwen": "Yes"}
{"id": "68597068", "revid": "19404073", "url": "https://en.wikipedia.org/wiki?curid=68597068", "title": "2021–22 Albanian Cup", "text": "2021–22 Albanian Cup  was the seventieth season of Albania's annual cup competition, the Albanian Cup. Vllaznia defended the trophy, winning their eighth title in the competition.\nFormat.\nTies were played in a two-legged format similar to those of European competitions. If the aggregate score was tied after both games, the match was decided by extra time and a penalty shoot-out, if necessary.\nPreliminary round.\nIn order to reduce the number of participating teams for the First round to 32, a preliminary tournament is played. In contrast to the main tournament, the preliminary tournament is held as a single-leg knock-out competition. The matches were played on 11 September 2021.\nLuzi 2008 advanced to the first round.\nLabëria advanced to the first round.\nFirst round.\nAll 30 eligible teams of the 2021–22 Kategoria Superiore and 2021–22 Kategoria e Parë will enter in this round along with 6 teams from Kategoria e Dytë. The matches were played on 22 September 2021, 13 and 14 October 2021.\nTeuta advanced to the second round.\nPartizani advanced to the second round.\nTirana advanced to the second round.\nSkënderbeu advanced to the second round.\nBylis advanced to the second round.\nDinamo Tirana advanced to the second round.\nBesëlidhja advanced to the second round.\nKorabi advanced to the second round.\nVllaznia advanced to the second round.\nLaçi advanced to the second round.\nKukësi advanced to the second round.\nKastrioti advanced to the second round.\nFlamurtari advanced to the second round.\nEgnatia advanced to the second round.\nTomori advanced to the second round.\nPogradeci advanced to the second round.\nSecond round.\nAll the 16 qualified teams from the First Round progressed to the Second Round. The first legs were played on 3 November 2021 and the second legs took place on 17 and 18 November 2021.\nTeuta advanced to the quarter finals.\nPartizani advanced to the quarter finals.\nDinamo Tirana advanced to the quarter finals.\nSkënderbeu advanced to the quarter finals.\nVllaznia advanced to the quarter finals.\nLaçi advanced to the quarter finals.\nEgnatia advanced to the quarter finals.\nFlamurtari advanced to the quarter finals.\nQuarter-finals.\nAll eight qualified teams from the second round progressed to the quarter-finals. The first legs were played on 26 and 27 January 2022 and the second legs took place on 9 and 10 February 2022.\nTeuta advanced to the semi finals.\nPartizani advanced to the semi finals.\nVllaznia advanced to the semi finals.\nLaçi advanced to the semi finals.\nSemi-finals.\nThe first legs were played on 30 and 31 March and the second legs were played on 13 April 2022.\nVllaznia advanced to the final.\nLaçi advanced to the final.", "Engineering,_Manufacturing": 0.9897151589, "qwen": "Yes"}
{"id": "710115", "revid": "18040497", "url": "https://en.wikipedia.org/wiki?curid=710115", "title": "Ultrasonic welding", "text": "Ultrasonic welding is an industrial process whereby high-frequency ultrasonic acoustic vibrations are locally applied to work pieces being held together under pressure to create a solid-state weld. It is commonly used for plastics and metals, and especially for joining dissimilar materials. In ultrasonic welding, there are no connective bolts, nails, soldering materials, or adhesives necessary to bind the materials together. When used to join metals, the temperature stays well below the melting point of the involved materials, preventing any unwanted properties which may arise from high temperature exposure of the metal.\nHistory.\nPractical application of ultrasonic welding for rigid plastics was completed in the 1960s. At this point only hard plastics could be welded. The patent for the ultrasonic method for welding rigid thermoplastic parts was awarded to Robert Soloff and Seymour Linsley in 1965. Soloff, the founder of Sonics & Materials Inc., was a lab manager at Branson Instruments where thin plastic films were welded into bags and tubes using ultrasonic probes. He unintentionally moved the probe close to a plastic tape dispenser and observed that the halves of the dispenser welded together. He realized that the probe did not need to be manually moved around the part, but that the ultrasonic energy could travel through and around rigid plastics and weld an entire joint. He went on to develop the first ultrasonic press. The first application of this new technology was in the toy industry.\nThe first car made entirely out of plastic was assembled using ultrasonic welding in 1969. The automotive industry has used it regularly since the 1980s, and it is now used for a multitude of applications. \nProcess.\nFor joining complex injection molded thermoplastic parts, ultrasonic welding equipment can be easily customized to fit the exact specifications of the parts being welded. The parts are sandwiched between a fixed shaped nest (anvil) and a sonotrode (horn) connected to a transducer, and a ~20 kHz low-amplitude acoustic vibration is emitted. (Note: Common frequencies used in ultrasonic welding of thermoplastics are 15 kHz, 20 kHz, 30 kHz, 35 kHz, 40 kHz and 70 kHz). When welding plastics, the interface of the two parts is specially designed to concentrate the melting process. One of the materials usually has a spiked or rounded energy director which contacts the second plastic part. The ultrasonic energy melts the point contact between the parts, creating a joint. Ultrasonic welding of thermoplastics causes local melting of the plastic due to absorption of vibrational energy along the joint to be welded. In metals, welding occurs due to high-pressure dispersion of surface oxides and local motion of the materials. Although there is heating, it is not enough to melt the base materials.\nUltrasonic welding can be used for both hard and soft plastics, such as semicrystalline plastics, and metals. The understanding of ultrasonic welding has increased with research and testing. The invention of more sophisticated and inexpensive equipment and increased demand for plastic and electronic components has led to a growing knowledge of the fundamental process. However, many aspects of ultrasonic welding still require more study, such as relating weld quality to process parameters. Ultrasonic welding continues to be a rapidly developing field.\nScientists from the Institute of Materials Science and Engineering (WKK) of University of Kaiserslautern, with the support from the German Research Foundation (Deutsche Forschungsgemeinschaft), have succeeded in proving that using ultrasonic welding processes can lead to highly durable bonds between light metals and carbon-fiber-reinforced polymer (CFRP) sheets.\nThe benefit of ultrasonic welding is that the drying time is much shorter than conventional adhesives or solvents, so the workpieces do not need to remain in a fixture for long time until the joint dries or cures. The welding can easily be automated, making clean and precise joints; the site of the weld is very clean and rarely requires any touch-up work. The low thermal impact on the materials involved enables a greater number of materials to be welded together. The process is a good automated alternative to glue, screws or snap-fit designs. It is typically used with small parts (e.g. cell phones, consumer electronics, disposable medical tools, toys, etc.) but it can be used on parts as large as a small automotive instrument cluster. Ultrasonics can also be used to weld metals, but are typically limited to small welds of thin, malleable metals, e.g. aluminum, copper, nickel. Ultrasonics would not be used in welding the chassis of an automobile or in welding pieces of a bicycle together, due to the power levels required.\nComponents.\nAll ultrasonic welding systems are composed of the same basic elements:\nApplications.\nThe applications of ultrasonic welding are extensive and are found in many industries including electrical and computer, automotive and aerospace, medical, and packaging. Whether two items can be ultrasonically welded is determined by their thickness. If they are too thick this process will not join them. This is the main obstacle in the welding of metals. However, wires, microcircuit connections, sheet metal, foils, ribbons and meshes are often joined using ultrasonic welding. Ultrasonic welding is a very popular technique for bonding thermoplastics. It is fast and easily automated with weld times often below one second and there is no ventilation system required to remove heat or exhaust. This type of welding is often used to build assemblies that are too small, too complex, or too delicate for more common welding techniques.\nComputer and electrical industries.\nIn the electrical and computer industry ultrasonic welding is often used to join wired connections and to create connections in small, delicate circuits. Junctions of wire harnesses are often joined using ultrasonic welding. Wire harnesses are large groupings of wires used to distribute electrical signals and power. Electric motors, field coils, transformers and capacitors may also be assembled with ultrasonic welding. It is also often preferred in the assembly of storage media such as flash drives and computer disks because of the high volumes required. Ultrasonic welding of computer disks has been found to have cycle times of less than 300 ms.\nOne of the areas in which ultrasonic welding is most used and where new research and experimentation is centered is microcircuits. This process is ideal for microcircuits since it creates reliable bonds without introducing impurities or thermal distortion into components. Semiconductor devices, transistors and diodes are often connected by thin aluminum and gold wires using ultrasonic welding. It is also used for bonding wiring and ribbons as well as entire chips to microcircuits. An example of where microcircuits are used is in medical sensors used to monitor the human heart in bypass patients.\nOne difference between ultrasonic welding and traditional welding is the ability of ultrasonic welding to join dissimilar materials. The assembly of battery components is a good example of where this ability is utilized. When creating battery and fuel cell components, thin gauge copper, nickel and aluminium connections, foil layers and metal meshes are often ultrasonically welded together. Multiple layers of foil or mesh can often be applied in a single weld eliminating steps and costs.\nAerospace and automotive industries.\nFor automobiles, ultrasonic welding tends to be used to assemble large plastic and electrical components such as instrument panels, door panels, lamps, air ducts, steering wheels, upholstery and engine components. As plastics have continued to replace other materials in the design and manufacture of automobiles, the assembly and joining of plastic components has increasingly become a critical issue. Some of the advantages for ultrasonic welding are low cycle times, automation, low capital costs, and flexibility. Ultrasonic welding does not damage surface finish because the high-frequency vibrations prevent marks from being generated, which is a crucial consideration for many car manufacturers, .\nUltrasonic welding is generally utilized in the aerospace industry when joining thin sheet gauge metals and other lightweight materials. Aluminum is a difficult metal to weld using traditional techniques because of its high thermal conductivity. However, it is one of the easier materials to weld using ultrasonic welding because it is a softer metal and thus a solid-state weld is simple to achieve. Since aluminum is so widely used in the aerospace industry, it follows that ultrasonic welding is an important manufacturing process. With the advent of new composite materials, ultrasonic welding is becoming even more prevalent. It has been used in the bonding of the popular composite material carbon fiber. Numerous studies have been done to find the optimum parameters that will produce quality welds for this material.\nMedical industry.\nIn the medical industry ultrasonic welding is often used because it does not introduce contaminants or degradation into the weld and the machines can be specialized for use in clean rooms. The process can also be highly automated, provides strict control over dimensional tolerances and does not interfere with the biocompatibility of parts. Therefore, it increases part quality and decreases production costs. Items such as arterial filters, anesthesia filters, blood filters, IV catheters, dialysis tubes, pipettes, cardiometry reservoirs, blood/gas filters, face masks and IV spike/filters can all be made using ultrasonic welding. Another important application in the medical industry for ultrasonic welding is textiles. Items like hospital gowns, sterile garments, masks, transdermal patches and textiles for clean rooms can be sealed and sewn using ultrasonic welding. This prevents contamination and dust production and reduces the risk of infection.\nPackaging industry.\nUltrasonic welding is often used in packaging applications. Many common items are either created or packaged using ultrasonic welding. Sealing containers, tubes and blister packs are common applications.\nUltrasonic welding is also applied in the packaging of dangerous materials, such as explosives, fireworks and other reactive chemicals. These items tend to require hermetic sealing, but cannot be subjected to high temperatures. One example is a butane lighter. This container weld must be able to withstand high pressure and stress and must be airtight to contain the butane. Another example is the packaging of ammunition and propellants. These packages must be able to withstand high pressure and stress to protect the consumer from the contents. \nThe food industry finds ultrasonic welding preferable to traditional joining techniques, because it is fast, sanitary and can produce hermetic seals. Milk and juice containers are examples of products often sealed using ultrasonic welding. The paper parts to be sealed are coated with plastic, generally polypropylene or polyethylene, and then welded together to create an airtight seal. The main obstacle to overcome in this process is the setting of the parameters. For example, if over-welding occurs, then the concentration of plastic in the weld zone may be too low and cause the seal to break. If it is under-welded, the seal is incomplete. Variations in the thicknesses of materials can cause variations in weld quality. Some other food items sealed using ultrasonic welding include candy bar wrappers, frozen food packages and beverage containers.\nExperimental.\n\"Sonic agglomeration\", a combination of ultrasonic welding and molding, is used to produce compact food ration bars for the US Army's Close Combat Assault Ration project without the use of binders. Dried food is pressed into a mold and welded for an hour, during which food particles become stuck together.\nSafety.\nHazards of ultrasonic welding include exposure to high temperatures and voltages. This equipment should be operated using the safety guidelines provided by the manufacturer to avoid injury. For instance, operators must never place hands or arms near the welding tip when the machine is activated. Also, operators should be provided with hearing protection and safety glasses. Operators should be informed of government agency regulations for the ultrasonic welding equipment and these regulations should be enforced.\nUltrasonic welding machines require routine maintenance and inspection. Panel doors, housing covers and protective guards may need to be removed for maintenance. This should be done when the power to the equipment is off and only by the trained professional servicing the machine.\nSub-harmonic vibrations, which can create annoying audible noise, may be caused in larger parts near the machine due to the ultrasonic welding frequency. This noise can be damped by clamping these large parts at one or more locations. Also, high-powered welders with frequencies of 15 kHz and 20 kHz typically emit a potentially damaging high-pitched squeal in the range of human hearing. Shielding this radiating sound can be done using an acoustic enclosure.", "Engineering,_Manufacturing": 1.0000065565, "qwen": "Yes"}
{"id": "13283224", "revid": "40051386", "url": "https://en.wikipedia.org/wiki?curid=13283224", "title": "People Powered Vehicle", "text": "The People Powered Vehicle, or PPV, was a two-person pedal-powered car introduced in the United States during the oil crisis of the early 1970s. Manufactured by EVI of Sterling Heights, Michigan, it sold for less than $400. Although it offered luggage space and was marketed as a fun and practical vehicle, it offered limited weather protection and was not fast enough to substitute for a car.\nThe PPV may be considered a forerunner of the modern velomobile. This tricycle was manufactured with a three-speed, floor shift, open type transmission with a single-wheel drive. Either the driver or the passenger could pedal independently or as a team. Reverse was accomplished by reaching outside and turning one of the rear wheels by hand. At one time, a rear-hinged, surrey top was available. Most were manufactured with a dark blue bottom and a white hood. Red or yellow bottoms with white tops were also offered. Sometimes bicycle accessories were added, e.g. squeeze bulb horn and a rear view mirror.\nThe PPV was designed for two adult riders, and with frame and body the total weight could approach three times that of a conventional single-rider bicycle. However, the PPV was fitted with just one brake, of a type intended to be just one of two brakes on a conventional single-rider bicycle (an Atom drum brake built in to the front wheel). Thus, even at relaxed speeds on level ground, the PPV brakes were dangerously inadequate.\nAn upgraded version of this vehicle is currently (2011) being offered by the International Surrey Company Ltd. under the trade name Impello.", "Engineering,_Manufacturing": 0.9996287823, "qwen": "Yes"}
{"id": "1112994", "revid": "31026899", "url": "https://en.wikipedia.org/wiki?curid=1112994", "title": "CNC wood router", "text": "A CNC wood router is a CNC router tool that creates objects from wood. CNC stands for \"computer numerical control\". The CNC works on the Cartesian coordinate system (X, Y, Z) for 3D motion control. Parts of a project can be designed in the computer with a CAD/CAM program, and then cut automatically using a router or other cutters to produce a finished part.\nThe CNC router is ideal for hobbies, engineering prototyping, product development, art, and production work.\nOperation.\nA CNC wood router uses CNC (computer numerical control) and is similar to a metal CNC mill with the following differences:\nA wood router is controlled in the same way as a metal mill, but there are CAM and CAD applications such as Artcam, Mastercam, Bobcad, and AlphaCam, which are specifically designed for use with wood routers.\nWood routers are frequently used to machine other soft materials such as plastics.\nTypical three-axis CNC wood routers are generally much bigger than their metal shop counterparts. 5' x 5', 4' x 8', and 5' x 10' are typical bed sizes for wood routers. They can be built to accommodate very large sizes up to, but not limited to 12' x 100'. The table can move, allowing for true three axis (xyz) motion, or the gantry can move, which requires the third axis to be controlled by two slaved servo motors.\nAdvantages.\nThe advantages of CNC wood router (compared to general machine) as follows,\nComponents.\nSeparate heads.\nSome wood routers have multiple separate heads that can come down simultaneously or not. Some routers have multiple heads that can run complete separate programs on separate tables all while being controlled by the same interface.\nDust collection / vacuum collector.\nThe wood router typically has 6\"-10\" air ducts to suck up the wood chips and dust created. They can be piped to a stand-alone or full shop dust collection system.\nSome wood routers are specialized for cabinetry and have many drills that can be programmed to come down separately or together. The drills are generally spaced 32 mm apart on centres - a spacing system called 32 mm System. This is for the proper spacing of shelving for cabinets. Drilling can be vertical or horizontal (in the Y or X axis from either side/end of the workpiece) which allows a panel to be drilled on all four edges as well as the top surface. Many of these machines with large drilling arrays are derived from CNC point-to-point borers.\nSecuring the workpiece.\nSuction systems.\nThe wood router typically holds wood with suction through the table or pods that raise the work above the table. Pods may be used for components which require edge profiling (or undercutting), are manufactured from solid wood or where greater flexibility in production is required. This type of bed requires less extraction with greater absolute vacuum.\nA second type hold down uses a spoil board. This allows vacuum suction through a low density table and allows the placement of parts anywhere on the table. These types of tables are typically used for nest-based manufacturing (NBM) where multiple components are routed from a single sheet. This type of manufacturing precludes edge drilling or undercut edge work on components.\nVacuum pumps are required with both types of tables where volume and \"strength\" are determined based on the types of materials being cut.\nMaintenance.\nProper operation and maintenance in right way can greatly extend machine's life and reduce the incidence of failures.", "Engineering,_Manufacturing": 0.9999507666, "qwen": "Yes"}
{"id": "1114008", "revid": "42204915", "url": "https://en.wikipedia.org/wiki?curid=1114008", "title": "Pinout", "text": "In electronics, a pinout (sometimes written \"pin-out\") is a cross-reference between the contacts, or \"pins\", of an electrical connector or electronic component, and their functions. \"Pinout\" now supersedes the term \"basing diagram\" which was the standard terminology used by the manufacturers of vacuum tubes and the RMA. The RMA started its standardization in 1934, collecting and correlating tube data for registration at what was to become the EIA. The EIA (Electronic Industries Alliance) now has many sectors reporting to it and sets what is known as EIA standards where all registered pinouts and registered jacks can be found.\nPurpose.\nThe functions of contacts in electrical connectors, be they power- or signaling-related, must be specified for connectors to be interchangeable. Each connector contact must mate with the contact on the other connector with the same function. If contacts of disparate functions are allowed to make contact, the connection may fail, and damage may result. Therefore, pinouts are a vital reference when building and testing connectors, cables, and adapters.\nSuppose one has specified wires within a cable (for instance, the colored Ethernet cable wires in ANSI/TIA-568 T568A). In that case, the order in which different color wires are attached to pins of an electrical connector defines the wiring scheme. In any multi-pin connector, there are multiple ways to map wires to pins, so different configurations may be created that superficially look identical but function differently. Pinouts define these configurations. Many connectors have multiple standard pinouts in use for different manufacturers or applications.\nTerminology.\nWhile one usage of the word \"pin\" is to refer to electrical contacts of, specifically, the male gender, its usage in \"pinout\" does not imply gender: the contact-to-function cross-reference for a connector that has only female socket contacts is still called a \"pinout\".\nRepresentation.\nThe pinout can typically be shown as a table or diagram. However, it is necessary to clarify how to view the diagram, stating if it shows the backside of the connector (where wires are attached) or the \"mating face\" of the connector. Published pinouts, which are particularly important when different manufacturers want to interconnect their products using open standards, are typically provided by the connector or equipment manufacturer. However, some pinouts are provided by 3rd parties since the manufacturer does not well document some connectors.\nWhile repairing electronic devices, an electronics technician uses electronic test equipment to \"pin out\" each component on a PCB. The technician probes each pin of the component in turn, comparing the expected signal on each pin to the actual signal on that pin.\nExample pinouts.\nUSB pinout.\nViewed from the front (outside) of Female Type A USB receptacle:", "Engineering,_Manufacturing": 0.9967676997, "qwen": "Yes"}
{"id": "531911", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=531911", "title": "Laser cutting", "text": "Laser cutting is a technology that uses a laser to vaporize materials, resulting in a cut edge. While typically used for industrial manufacturing applications, it is now used by schools, small businesses, architecture, and hobbyists. Laser cutting works by directing the output of a high-power laser most commonly through optics. The laser optics and CNC (computer numerical control) are used to direct the laser beam to the material. A commercial laser for cutting materials uses a motion control system to follow a CNC or G-code of the pattern to be cut onto the material. The focused laser beam is directed at the material, which then either melts, burns, vaporizes away, or is blown away by a jet of gas, leaving an edge with a high-quality surface finish.\nHistory.\nIn 1965, the first production laser cutting machine was used to drill holes in diamond dies. This machine was made by the Western Electric Engineering Research Center. In 1967, the British pioneered laser-assisted oxygen jet cutting for metals. In the early 1970s, this technology was put into production to cut titanium for aerospace applications. At the same time, CO2 lasers were adapted to cut non-metals, such as textiles, because, at the time, CO2 lasers were not powerful enough to overcome the thermal conductivity of metals.\nProcess.\nThe laser beam is generally focused using a high-quality lens on the work zone. The quality of the beam has a direct impact on the focused spot size. The narrowest part of the focused beam is generally less than in diameter. Depending upon the material thickness, kerf widths as small as are possible. In order to be able to start cutting from somewhere other than the edge, a pierce is done before every cut. Piercing usually involves a high-power pulsed laser beam which slowly makes a hole in the material, taking around 5–15 seconds for stainless steel, for example.\nThe parallel rays of coherent light from the laser source often fall in the range between in diameter. This beam is normally focused and intensified by a lens or a mirror to a very small spot of about to create a very intense laser beam. In order to achieve the smoothest possible finish during contour cutting, the direction of the beam polarization must be rotated as it goes around the periphery of a contoured workpiece. For sheet metal cutting, the focal length is usually .\nAdvantages of laser cutting over mechanical cutting include easier work holding and reduced contamination of workpiece (since there is no cutting edge which can become contaminated by the material or contaminate the material). Precision may be better since the laser beam does not wear during the process. There is also a reduced chance of warping the material that is being cut, as laser systems have a small heat-affected zone. Some materials are also very difficult or impossible to cut by more traditional means.\nLaser cutting for metals has the advantage over plasma cutting of being more precise and using less energy when cutting sheet metal; however, most industrial lasers cannot cut through the greater metal thickness that plasma can. Newer laser machines operating at higher power (6000 watts, as contrasted with early laser cutting machines' 1500-watt ratings) are approaching plasma machines in their ability to cut through thick materials, but the capital cost of such machines is much higher than that of plasma cutting machines capable of cutting thick materials like steel plate.\nTypes.\nThere are three main types of lasers used in laser cutting. The laser is suited for cutting, boring, and engraving. The neodymium (Nd) and neodymium yttrium-aluminium-garnet  lasers are identical in style and differ only in the application. Nd is used for boring and where high energy but low repetition are required. The Nd:YAG laser is used where very high power is needed and for boring and engraving. Both and Nd/Nd:YAG lasers can be used for welding.\n lasers are commonly \"pumped\" by passing a current through the gas mix (DC-excited) or using radio frequency energy (RF-excited). The RF method is newer and has become more popular. Since DC designs require electrodes inside the cavity, they can encounter electrode erosion and plating of electrode material on glassware and optics. Since RF resonators have external electrodes they are not prone to those problems.\n lasers are used for the industrial cutting of many materials including titanium, stainless steel, mild steel, aluminium, plastic, wood, engineered wood, wax, fabrics, and paper. YAG lasers are primarily used for cutting and scribing metals and ceramics.\nIn addition to the power source, the type of gas flow can affect performance as well. Common variants of lasers include fast axial flow, slow axial flow, transverse flow, and slab. In a fast axial flow resonator, the mixture of carbon dioxide, helium, and nitrogen is circulated at high velocity by a turbine or blower. Transverse flow lasers circulate the gas mix at a lower velocity, requiring a simpler blower. Slab or diffusion-cooled resonators have a static gas field that requires no pressurization or glassware, leading to savings on replacement turbines and glassware.\nThe laser generator and external optics (including the focus lens) require cooling. Depending on system size and configuration, waste heat may be transferred by a coolant or directly to air. Water is a commonly used coolant, usually circulated through a chiller or heat transfer system.\nA \"laser microjet\" is a water-jet-guided laser in which a pulsed laser beam is coupled into a low-pressure water jet. This is used to perform laser cutting functions while using the water jet to guide the laser beam, much like an optical fiber, through total internal reflection. The advantages of this are that the water also removes debris and cools the material. Additional advantages over traditional \"dry\" laser cutting are high dicing speeds, parallel kerf, and omnidirectional cutting.\nFiber lasers are a type of solid-state laser that is rapidly growing within the metal cutting industry. Unlike CO2, Fiber technology utilizes a solid gain medium, as opposed to a gas or liquid. The “seed laser” produces the laser beam and is then amplified within a glass fiber. With a wavelength of only 1064 nanometers fiber lasers produce an extremely small spot size (up to 100 times smaller compared to the CO2) making it ideal for cutting reflective metal material. This is one of the main advantages of Fiber compared to CO2.\nFibre laser cutter benefits include:-\nMethods.\nThere are many different methods of cutting using lasers, with different types used to cut different materials. Some of the methods are vaporization, melt and blow, melt blow and burn, thermal stress cracking, scribing, cold cutting, and burning stabilized laser cutting.\nVaporization cutting.\nIn vaporization cutting, the focused beam heats the surface of the material to a flashpoint and generates a keyhole. The keyhole leads to a sudden increase in absorptivity quickly deepening the hole. As the hole deepens and the material boils, vapor generated erodes the molten walls blowing ejection out and further enlarging the hole. Nonmelting materials such as wood, carbon, and thermoset plastics are usually cut by this method.\nMelt and blow.\nMelt and blow or fusion cutting uses high-pressure gas to blow molten material from the cutting area, greatly decreasing the power requirement. First, the material is heated to melting point then a gas jet blows the molten material out of the kerf avoiding the need to raise the temperature of the material any further. Materials cut with this process are usually metals.\nThermal stress cracking.\nBrittle materials are particularly sensitive to thermal fracture, a feature exploited in thermal stress cracking. A beam is focused on the surface causing localized heating and thermal expansion. This results in a crack that can then be guided by moving the beam. The crack can be moved in order of m/s. It is usually used in the cutting of glass.\nStealth dicing of silicon wafers.\nThe separation of microelectronic chips as prepared in semiconductor device fabrication from silicon wafers may be performed by the so-called stealth dicing process, which operates with a pulsed , the wavelength of which (1064 nm) is well adapted to the electronic band gap of silicon (1.11 eV or 1117 nm).\nReactive cutting.\nReactive cutting is also called \"burning stabilized laser gas cutting\" and \"flame cutting\". Reactive cutting is like oxygen torch cutting but with a laser beam as the ignition source. Mostly used for cutting carbon steel in thicknesses over 1 mm. This process can be used to cut very thick steel plates with relatively little laser power.\nTolerances and surface finish.\nLaser cutters have a positioning accuracy of 10 micrometers and repeatability of 5 micrometers.\nStandard roughness Rz increases with the sheet thickness, but decreases with laser power and cutting speed. When cutting low carbon steel with laser power of 800 W, standard roughness Rz is 10 μm for sheet thickness of 1 mm, 20 μm for 3 mm, and 25 μm for 6 mm.\nformula_1\nWhere: formula_2 steel sheet thickness in mm; formula_3 laser power in kW (some new laser cutters have laser power of 4 kW); formula_4 cutting speed in meters per minute.\nThis process is capable of holding quite close tolerances, often to within 0.001 inch (0.025 mm). Part geometry and the mechanical soundness of the machine have much to do with tolerance capabilities. The typical surface finish resulting from laser beam cutting may range from 125 to 250 micro-inches (0.003 mm to 0.006 mm).\nMachine configurations.\nThere are generally three different configurations of industrial laser cutting machines: moving material, hybrid, and flying optics systems. These refer to the way that the laser beam is moved over the material to be cut or processed. For all of these, the axes of motion are typically designated X and Y axis. If the cutting head may be controlled, it is designated as the Z-axis.\nMoving material lasers have a stationary cutting head and move the material under it. This method provides a constant distance from the laser generator to the workpiece and a single point from which to remove cutting effluent. It requires fewer optics but requires moving the workpiece. This style of machine tends to have the fewest beam delivery optics but also tends to be the slowest.\nHybrid lasers provide a table that moves in one axis (usually the X-axis) and moves the head along the shorter (Y) axis. This results in a more constant beam delivery path length than a flying optic machine and may permit a simpler beam delivery system. This can result in reduced power loss in the delivery system and more capacity per watt than flying optics machines.\nFlying optics lasers feature a stationary table and a cutting head (with a laser beam) that moves over the workpiece in both of the horizontal dimensions. Flying optics cutters keep the workpiece stationary during processing and often do not require material clamping. The moving mass is constant, so dynamics are not affected by varying the size of the workpiece. Flying optics machines are the fastest type, which is advantageous when cutting thinner workpieces.\nFlying optic machines must use some method to take into account the changing beam length from the near field (close to the resonator) cutting to the far field (far away from the resonator) cutting. Common methods for controlling this include collimation, adaptive optics, or the use of a constant beam length axis.\nFive and six-axis machines also permit cutting formed workpieces. In addition, there are various methods of orienting the laser beam to a shaped workpiece, maintaining a proper focus distance and nozzle standoff, etc.\nPulsing.\nPulsed lasers which provide a high-power burst of energy for a short period are very effective in some laser cutting processes, particularly for piercing, or when very small holes or very low cutting speeds are required, since if a constant laser beam were used, the heat could reach the point of melting the whole piece being cut.\nMost industrial lasers have the ability to pulse or cut CW (continuous wave) under NC (numerical control) program control.\nDouble pulse lasers use a series of pulse pairs to improve material removal rate and hole quality. Essentially, the first pulse removes material from the surface and the second prevents the ejecta from adhering to the side of the hole or cut.\nPower consumption.\nThe main disadvantage of laser cutting is the high power consumption. Industrial laser efficiency may range from 5% to 45%. The power consumption and efficiency of any particular laser will vary depending on output power and operating parameters. This will depend on the type of laser and how well the laser is matched to the work at hand. The amount of laser cutting power required, known as \"heat input\", for a particular job depends on the material type, thickness, process (reactive/inert) used, and desired cutting rate.\nProduction and cutting rates.\nThe maximum cutting rate (production rate) is limited by a number of factors including laser power, material thickness, process type (reactive or inert), and material properties. Common industrial systems (≥1 kW) will cut carbon steel metal from in thickness. For many purposes, a laser can be up to thirty times faster than standard sawing.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "48196084", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=48196084", "title": "Onanon", "text": "Onanon is a design, engineering and manufacturing company specializing in the automating panel array manufacturing process, which can produce multiple units in a single session. The company utilizes engineered plastics for manufacturing, using high-speed machinery and automation to produce connectors in large batches. The process removes the need for human handling, thus reducing the probability of error. Onanon utilizes printed circuit boards as a base to add other components. Headquartered in Milpitas, California, Onanon is the first company to introduce a PC board as a connector pin substrate, a technique which is considered standard today but was seen as revolutionary at the time.\nHistory.\nOnanon was founded in 1979 as a design, prototype and manufacturing firm specializing in value add connectors and cable assemblies with integrated electronics. The company branched into custom connector design, which has become its chief manufacturing method. Onanon uses multiple head automation in its manufacturing process, which increases the number of units that can be produced. The company has a proprietary “breadboard” panel array manufacturing method that allows engineers to build functionality directly into the connector, which saves costs for the buyer and adds functionality to the connector. Onanon employs a sales staff that is also trained as engineers, which allows the company to guarantee fast turnaround times for shipments placed by customers.\nProducts.\nOnanon makes several products in the medical and industrial sectors. Because of the highly customizable nature of the company’s products, the company sells based on type or industry use. Onanon plans to build future products with an open architecture, allowing others to borrow from their design ideas.\nCircuit Boards.\nOnanon manufactures advanced PC circuitry using a mostly automated batch method, in order to produce industrial computer boards for the industrial and healthcare sectors. With RoHS (restriction on hazardous substances), demand for solderless boards has surged.\nCustom Connectors.\nEngineered plastic connectors made to any size or shape. Connectors can take passive or active electrical components, and pin count can vary as needed. Onanon also produces female clips and connectors.\nMedical Connectors.\nHighly sensitive connectors that are designed to process inputs from the source. This allows OEMs to embed value-added microscale systems with intelligent designs. Onanon also makes embedded electronic connectors, which can boost signal strength or act as a shield to reduce EMI. Onanon also has rapid wire-termination technology, which reduces the need for solder that can potentially damage a PCB.\nMedical Cables.\nOnanon medical cable assemblies are designed to meet each unique medical device application. Onanon’s vertical manufacturing facility, houses rapid automated wire termination, molding, over-molding, SMT component placement, automated connector pin assembly. This allows OEM’s to have a globally cost competitive reliable source for their medical cable assemblies.\nSensors.\nOnanon connectors could be used as high-level, low impedance amplifiers in devices that send analog signals back and forth. Using the breadboard manufacturing technique, engineers can place operational amplifiers directly onto the connectors, which has the added benefit of reducing the need for wiring as well.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "48207249", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=48207249", "title": "Garrod and Lofthouse", "text": "Garrod and Lofthouse were a British printing company based in Chaldon Road, Caterham, Surrey, who manufactured record sleeves. In 1963, the company patented the design for Two-Piece sleeves that were used in the UK.\nThe advantage of these sleeves, in the days of single colour printing, was that the four-colour front was printed on a separate sheet to the single colour back and the two halves were then glued together as the sleeve was fabricated. This allowed half the number of passes through a printing press to produce the front cover, and a quarter for the monochrome backs. This gave a reduction in print costs of 37.5%. As the two fronts could be laminated together, it halved the amount of laminating time.\nBecause of these cost reductions the company were contracted to print sleeves for 90% of all EMI affiliated labels volume on the basis that they never produced a sleeve for Decca Records, their only major competitor. They are therefore credited on all original LP releases of the Beatles, including \"Sgt. Pepper's Lonely Hearts Club Band\".\nGarrod and Lofthouse printed for most UK record companies outside Decca, and manufactured covers for France through a subsidiary Imprimerie du Nord. They were given special permission to press the Rolling Stones' \"Beggars Banquet\" (one of the first gatefold sleeves) and \"Sticky Fingers\" (manufactured with a metal zip glued down the front), as Decca's in-house staff could not manage the complex production to the volume required.\nThe company was liquidated in 1988, by which time sleeve manufacturing could be done by any generic process, and cassette and compact disc sleeves did not require carboard printing.", "Engineering,_Manufacturing": 0.9994171858, "qwen": "Yes"}
{"id": "48232088", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=48232088", "title": "Constructive heuristic", "text": "A constructive heuristic is a type of heuristic method which starts with an empty solution and repeatedly extends the current solution until a complete solution is obtained. It differs from local search heuristics which start with a complete solution and then try to improve the current solution further via local moves. Examples of some famous problems that are solved using constructive heuristics are the flow shop scheduling, the vehicle routing problem and the open shop problem.", "Engineering,_Manufacturing": 0.9999277592, "qwen": "Yes"}
{"id": "48253458", "revid": "11222813", "url": "https://en.wikipedia.org/wiki?curid=48253458", "title": "Kryukiv Railway Car Building Works", "text": "Kriukiv Railway Car Manufacturing Plant (; KVBZ) is a large industrial company in Kremenchuk, Ukraine, manufacturing locomotives and multiple unit trains.\nHistory.\nThe foundation for the first buildings of the Krukiv Railway Car Manufacturing Plant was laid in 1869. As for 1900 there have been working 400 workers, who provided repairs for 120 freight and 20 passenger cars per month.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "26751966", "revid": "1099638865", "url": "https://en.wikipedia.org/wiki?curid=26751966", "title": "Gravimetric blender", "text": "A gravimetric blender is an item of industrial equipment used in the plastics industry to accurately weigh two or more components and then mix them together prior to processing in an injection molding machine, plastics extrusion, or blow moulding machine.\nThere are two types of gravimetric blender.\nLoss in weight\nThis type of gravimetric blender measures the \"loss in weight\" from two or more hoppers using a load cell under each hopper. Material is usually dispensed from the hoppers using a screw conveyor. All materials are dispensed together and the rate of dosing from each hopper is controlled to ensure the correct blend is achieved.\nGain in weight (sometimes called a batch blender)\nA gain in weight gravimetric blender has two or more hoppers arranged above a weigh-pan. These hoppers contain the components which are to be mixed, at the base of each hopper there is a valve to control the dispensing of material from the component hopper into the weigh-pan. The components are dispensed one at a time into the weigh pan until the target or batch weight is reached. Once the batch has been weighed out the contents of the weigh-pan are dispensed into a mixing chamber where they are blended. The resulting mixture exits the base of the mixing chamber into the processing machine.\nA typical application of a gravimetric blender would be mixing virgin plastic granules, recycled plastic, and masterbatch (an additive used to colour plastics) together.", "Engineering,_Manufacturing": 0.9999707937, "qwen": "Yes"}
{"id": "26759887", "revid": "211905", "url": "https://en.wikipedia.org/wiki?curid=26759887", "title": "List of the national championships of the SV Dynamo", "text": "With 280,000 members, it is not surprising that the SV Dynamo multi-sport club has won 2.187 championships in the GDR, so that a separate category should be needed.\nList.\nAcrobatics (Zircus).\nThe acrobats won 13 titles. \nArtistic roller skating.\nThe roller skaters won 2 titles.\nAthletics (track and field) men.\nThe men won over 212 championships in athletics (track and field).\nAthletics (track and field) ladies.\nThe ladies won over 196 titles.\nBiathlon.\nBiathletes won 45 titles.\nBobsleigh.\nBobsleighers won a single title.\nBoxing.\nBoxers won 71 titles.\nCross-country skiing.\nThe cross-county skiers won 90 titles. \nCycling.\nCyclists won 53 titles.\nFencing.\nFencers won 106 titles.\nFigure skating.\nFigure skaters won 31 titles.\nGymnastics.\nGymnasts won 110 titles.\nHandball.\nHandball teams won 9 titles.\nIce hockey.\nThe ice hockey teams won 38 titles in the smallest ice hockey league in the world. When the SC Dynamo Berlin was the champion, the SG Dynamo Weißwasser won the vice titles and when the SG Dynamo Weißwasser won the titles, the SC Dynamo Berlin won the vice medal.\nJudo.\nJudokas won 30 titles.\nMotorsport.\nThe athletes of motorsport won 74 titles.\nOrienteering.\nOrienteerers won 36 titles.\nParachuting.\nParachuters (women) won 64 titles.\nParachuters (men) won 57 titles.\nRiding.\nEquestrians won 17 titles.\nRowing.\nRowers won 133 titles, in one of the world bests league.\nRhythmic gymnastics.\nThe athletes in rhythmic gymnastics won 1 title\nSailing.\nThe sailors won 5 titles.\nShooting sports.\nMen and women shooters won 124 titles.\nShooting sports ladies.\nThe shooting ladies won 22 titles.\nSki alpin.\nThe skiers won 22 titles.\nSki Nordic / nordic combined.\nThe Dynamo-Athletes won in ski Nordic 23 titles.\nSki jumping.\n16 titles won the ski jumpers. \nSkittles (sport).\nThe skittlers won 2 titles.\nSoccer.\nFootball teams won 18 titles and 15 won in a row. \nSpeedskating.\nSpeedskaters won 121 titles.\nSwimming ladies.\n76 titles won the swimming ladies.\nSwimming men.\n98 titles won the swimmers.\nVolleyball.\nVolleyball teams won 25 titles.\nWater polo.\nWater polo teams won 17 titles.\nWeightlifting.\nWeightlifters won 9 titles.\nWrestling.\nThe wrestler won 168 titles.", "Engineering,_Manufacturing": 0.9989091158, "qwen": "Yes"}
{"id": "53416632", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=53416632", "title": "Cold Metal Transfer", "text": "Cold Metal Transfer (abbreviated CMT) is a welding method that is usually performed by a welding robot. The CMT machine detects a short circuit which sends a signal that retracts the welding filler material, giving the weld time to cool before each drop is placed. This leaves a smooth weld that is stronger than that of a hotter weld. This works well on thin metal that is prone to warping and the weld burning through the material. This type of welding is more efficient than other GMAW methods when the metal is thinner than 10mm, anything thicker and the expense begins to overcome traditional welding. Welding wire is fed through the system that is controlled by a computer, the computer adjusts things such as wire feed, welding speed, and amps going through the wire. This allows precise welding of materials like steel and aluminum, with very little slag and spatter, resulting in a cleaner finish weld.\nDefinition.\nCMT is a subset of gas metal arc welding. It works by reducing the weld current and retracting the weld wire when detecting a short circuit, resulting in a drop-by-drop deposit of weld material. Developed for thin materials, CMT requires strict control of weld parameters.\nHistory.\nCMT was originally intended for joining sheet metal in the automotive industry, but has expanded to thicker materials.\nApplication.\nCold metal transfer is used to weld different types of metal with various thicknesses. This low voltage, low heat welding works well on thin sheet metal. It is also being used for thicker material where the integrity of the weld is important. When metal is overheated it affects its structural properties, CMT welding keeps the heat to a minimum, resulting in little change to the structure of the metal, providing a stronger weld. Thin metal has a greater possibility of distorting when heated, during traditional GMAW welding heat sinks or other heat protection had to be used to prevent the warping of the metal, heat protection is not needed during the CMT process. CMT has a wide variety of applications in various industries such as small engine, automotive, and marine.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "443427", "revid": "40203704", "url": "https://en.wikipedia.org/wiki?curid=443427", "title": "Woodworking machine", "text": "A Woodworking machine is a machine that is intended to process wood. These machines are usually powered by electric motors and are used extensively in woodworking. Sometimes grinding machines (used for grinding down to smaller pieces) are also considered a part of woodworking machinery.\nTypes of woodworking machinery.\nArtisanal and hobby machines.\nThese machines are used both in small-scale commercial production of timber products and by hobbyists. Most of these machines may be used on solid timber and on composite products. Machines can be divided into the bigger stationary machines where the machine remains stationary while the material is moved over the machine, and hand-held power tools, where the tool is moved over the material.\nPanel Line Woodworking machines.\nThese machines are used in large-scale manufacturing of cabinets and other wooden or panel products.\nPanel surface processing.\nPanel dividing equipment.\nPanel dividing equipment, classified by number of beam, loading system, saw carriage speed\nDouble end tenoner.\nDouble end tenoner, classified by conveyor type\nPanel edge processing equipment.\nPanel edge processing equipment, classified by conveyor speed\nPanel boring equipment.\nclassified by number of boring heads", "Engineering,_Manufacturing": 0.9999102354, "qwen": "Yes"}
{"id": "6976434", "revid": "18188106", "url": "https://en.wikipedia.org/wiki?curid=6976434", "title": "Soda siphon", "text": "The soda siphon (sometimes spelled syphon), also known as the seltzer bottle, siphon seltzer bottle, or just siphon) is a device for storing and dispensing carbonated beverages (typically carbonated water) while maintaining the internal pressure, thereby preventing it from going flat. The carbonated beverage is dispensed using the internal pressure of the bottle, so the setup is not a true siphon in its operation.\nHistory.\nAs early as 1790, the concept of an \"aerosol\" was introduced in France, with self-pressurized carbonated beverages. The modern siphon was created in 1829, when two Frenchmen patented a hollow corkscrew which could be inserted into a soda bottle and, by use of a valve, allowed a portion of the contents to be dispensed while maintaining the pressure on the inside of the bottle and preventing the remaining soda from going flat.\nSoda siphons were popular in the 1920s and 1930s. The rise of bottled carbonated beverages and the destruction of many of the siphon manufacturers' plants in Eastern Europe during World War II led to a decline in their popularity in the years after the war. \nClassic bottles wrapped in metal mesh are still commonly used in some bars to make drinks, and are used to enhance a period ambiance in traditionally themed dining venues. \nModern-day production.\nCommercial production and delivery of pre-filled bottles of seltzer continued in the Southern California and Eastern Seaboard regions of the US into 2009. , such delivery service continues in Argentina (nationwide), Vienna, Austria by Brauerei Ottakringer and in Toronto, Ontario, Canada. , Coca-Cola Mexico began distributing its Ciel-branded mineral water in 1.75 litre plastic siphon bottles with a reusable plastic head assembly. In the UK, Adcocks Syphons remains the sole producer and bottler of siphons operating in the country, with several stockists selling their product throughout the country. Although Acqua Spumante reconditions and restores vintage siphons for the modern market, operating via an eBay store and own website.\nFilling.\nFor making single-use sealed bottles, or commercially refillable bottles in a seltzer plant, the bottles are first washed and then evacuated using a vacuum pump, and a rubber hose is slipped over the nozzle. The bottle with most of the air removed is then held upside-down under the surface of a tub of carbonated water, which is drawn into the bottle by the vacuum inside when the valve is opened. Sometimes a pump is used to force higher pressure into the bottle.\nFor portable 1 litre bottles, the head of the siphon bottle is removed for filling. A rubber seal and tube are also removed. Then about 1 litre of very cold water (which can absorb more carbon dioxide) is added to the bottle; the bottle is not completely filled. The rubber seal, tube, and head are then reassembled. An 8-gram CO2 charger is inserted and securely screwed into a port in the head; the port has a conical seal and a hollow pin that pierces the charger and lets the gas into the bottle. When the sound of the gas bubbling into the water is heard, the bottle is shaken, then left to rest. Within seconds, the trigger pull will release seltzer water.\nModern manufacturers such as SodaStream and Aqvia market soda machine systems which can carbonate beverages using larger carbon dioxide canisters, which may be more economical than the traditional small gas cartridges.", "Engineering,_Manufacturing": 0.9888970256, "qwen": "Yes"}
{"id": "2795027", "revid": "414836", "url": "https://en.wikipedia.org/wiki?curid=2795027", "title": "Exploded-view drawing", "text": "An exploded-view drawing is a diagram, picture, schematic or technical drawing of an object, that shows the relationship or order of assembly of various parts.\nIt shows the components of an object slightly separated by distance, or suspended in surrounding space in the case of a three-dimensional exploded diagram. An object is represented as if there had been a small controlled explosion emanating from the middle of the object, causing the object's parts to be separated an equal distance away from their original locations.\nThe exploded-view drawing is used in parts catalogs, assembly and maintenance manuals and other instructional material.\nThe projection of an exploded view is usually shown from above and slightly in diagonal from the left or right side of the drawing. (See exploded-view drawing of a gear pump to the right: it is slightly from above and shown from the left side of the drawing in diagonal.)\nOverview.\nAn exploded-view drawing is a type of drawing, that shows the intended assembly of mechanical or other parts. It shows all parts of the assembly and how they fit together. In mechanical systems usually the component closest to the center are assembled first, or is the main part in which the other parts get assembled. This drawing can also help to represent the disassembly of parts, where the parts on the outside normally get removed first.\nExploded diagrams are common in descriptive manuals showing parts placement, or parts contained in an assembly or sub-assembly. Usually such diagrams have the part identification number and a label indicating which part fills the particular position in the diagram. Many spreadsheet applications can automatically create exploded diagrams, such as exploded pie charts.\nIn patent drawings in an exploded views the separated parts should be embraced by a bracket, to show the relationship or order of assembly of various parts are permissible, see image. When an exploded view is shown in a figure that is on the same sheet as another figure, the exploded view should be placed in brackets.\nExploded views can also be used in architectural drawing, for example in the presentation of landscape design. An exploded view can create an image in which the elements are flying through the air above the architectural plan, almost like a cubist painting. The locations can be shadowed or dotted in the siteplan of the elements.\nHistory.\nThe exploded view was among the many graphic inventions of the Renaissance, which were developed to clarify pictorial representation in a renewed naturalistic way. The exploded view can be traced back to the early fifteenth century notebooks of Marino Taccola (1382–1453), and were perfected by Francesco di Giorgio (1439–1502) and Leonardo da Vinci (1452–1519).\nOne of the first clearer examples of an exploded view was created by Leonardo in his design drawing of a reciprocating motion machine. Leonardo applied this method of presentation in several other studies, including those on human anatomy.\nThe term \"Exploded-View Drawing\" emerged in the 1940s, and is one of the first times defined in 1965 as \"Three-dimensional (isometric) illustration that shows the mating relationships of parts, subassemblies, and higher assemblies. May also show the sequence of assembling or disassembling the detail parts.\"", "Engineering,_Manufacturing": 0.9984737635, "qwen": "Yes"}
{"id": "3596222", "revid": "39191556", "url": "https://en.wikipedia.org/wiki?curid=3596222", "title": "Rieger Tuning", "text": "Rieger, full name: Rieger Kfz-Kunststoffteile, Design und Tuning GmbH, are a German based tuning and bodykit manufacturer based in Eggenfelden.\nRieger Tuning was founded by Toni Rieger in a private garage in 1987. Rieger Tuning specializes in the development, production, and distribution of sport vehicle accessories, the focus being on body styling with the development and distribution of aerodynamic parts for the vehicles of predominantly European manufacture.\nSince inception Rieger has grown from a one-man operation into a Tuning Corporation with a 29 full time employees and approximately 15 part time employees.\nForeign trade is over 60 percent of its sales. The corporate headquarters for Rieger Tuning in Germany is located an hours drive east of Munich.\nA seven bay installation facility allows opportunity to work details of fitment so that when they send their products around the world installation instructions accompany each product.\nThe process of design, production and sale are completed under the same roof.\nAfter a new item idea follows the model and tool fabrication, which is completed in-house. Production of the acrylonitrile butadiene styrene (ABS) plastic components is carried out on the automatic vacuum thermoforming machine. The pre-cut blank of the finished ABS component is processed by the computer numerical control milling machines which guarantees an exact fit to the vehicle.\nThe warehouse allows nearly 95% of all Rieger parts to be available for immediate delivery. A new production and warehouse with nearly was built in 2003.", "Engineering,_Manufacturing": 0.998304069, "qwen": "Yes"}
{"id": "3597857", "revid": "7949351", "url": "https://en.wikipedia.org/wiki?curid=3597857", "title": "B & H Tool Works", "text": "B & H Tool Works, Inc. is a large tool and die company specializing in the design, build, and repair of Class \"A\" Progressive Dies. The company is headquartered in Richmond, Kentucky and was established in 1978 by Sammy Hammons and Tommy Brown. A second facility is located in Mount Vernon, Kentucky.\nAt the Richmond facility, capabilities include CNC machining, Wire EDM, and 5-Axis laser cutting services. Equipment used includes two CNC Vertical Machining Centers, one Mazak Turning Center, four Wire EDM Centers, and one Prima 5-Axis Laser. Recently the company upgraded one of its older CNC mills to a Kitamura MyCenter-7X and added an Agiecut Classic Gold 3S Wire EDM Center. The Laser Department includes 2 100-Ton press brakes used to form and bend lasercut parts.\nBesides tool and die, B & H Tool Works also runs production of metal stampings for several industries, the largest being automotive. The company serves as a Tier 2 supplier to several large automobile manufacturers for metal stampings and tooling.\nB&H now has 5 wire EDM machines and a total of 15 stamping presses. Recent construction has also added an additional of manufacturing and office space.", "Engineering,_Manufacturing": 0.9999902248, "qwen": "Yes"}
{"id": "25557935", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=25557935", "title": "EMO (trade show)", "text": "EMO is a European trade show for the manufacturing industries. It occurs every odd-numbered year, with a cycle that finds it at the Hanover Fairground in Hanover, Germany for 2 shows, then the Fiera Milano exhibition center in Milan, Italy for 1 show.\nThe name \"EMO\" came from the name Exposition Mondiale de la Machine-Outil (Machine Tool World Exposition), and the scope of the content still reflects the machine tool heritage, although it now also extends beyond it. The show covers the spectrum of metalworking technologies, such as machine tools for milling, turning, and forming; manufacturing systems; precision measuring tools; automated materials handling; computer technology; industrial electronics; and accessories. \nEMO is run by CECIMO, the European Association of the Machine Tool Industries (Comité européen de coopération des industries de la machine-outil) (www.cecimo.eu). The Verein Deutscher Werkzeugmaschinenfabriken (German Machine Tool Builders’ Association), or VDW, is responsible for the organization of the trade show when in Hanover, while UCIMU, the Association of Italian Manufacturers of Machine Tools, Robots, Automation Systems and ancillary products (NC, tools, components, accessories) manages the Milan show.\nAn agreement between the Association for Manufacturing Technology (AMT), which organizes the US-based International Manufacturing Technology Show (IMTS) and CECIMO coordinates the IMTS and the EMO such that every even-numbered year the IMTS is held in Chicago, and every odd-numbered year the EMO is held in Europe.\nHistory.\nEMO began as the EEMO (Exposition européenne de machines-outils, European machine tools exhibition). The first EEMO was held in 1951. The name changed in 1975 to EMO (Exposition Mondiale de la Machine-Outil). Nowadays its scope extends beyond machine tools, and the acronym expansion is not used by CECIMO anymore. ", "Engineering,_Manufacturing": 1.0000053644, "qwen": "Yes"}
{"id": "39648645", "revid": "1876660", "url": "https://en.wikipedia.org/wiki?curid=39648645", "title": "Industrial dryer", "text": "Industrial dryers are used to efficiently process large quantities of bulk materials that need reduced moisture levels. Depending on the amount and the makeup of material needing to be dried, industrial dryers come in many different models constructed specifically for the type and quantity of material to be processed. The most common types of industrial dryers are fluidized bed dryers, rotary dryers, rolling bed dryers, conduction dryers, convection dryers, pharmaceutical dryers, suspension/paste dryers, toroidal bed or TORBED dryers and dispersion dryers. Various factors are considered in determining the correct type of dryer for any given application, including the material to be dried, drying process requirements, production requirements, final product quality requirements and available facility space.", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "67028109", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=67028109", "title": "Workpiece", "text": "A workpiece is a piece, often made of a single material, that is being processed into another desired shape (such as building blocks).\nThe workpiece is usually a piece of relatively rigid material such as wood, metal, plastic, or stone. After a processing step, the workpiece may be moved on to further steps of processing. For example, a part can made out of bar stock and later become part of a semi-finished product.\nThe workpiece is often attached to the tool being used via a jig or fixture, like for example to a milling machine via an angle plate, or to a lathe via a lathe faceplate. A vise is another example of a simple type of fixture used to fix workpieces.\nA workpiece may be subjected to various cutting operations, like truing, making fillets, chamfers, countersinking, counterboring, etc. It may also receive various surface treatments and finishes.\nThe term \"workpiece\" has established itself within crafts and the manufacturing industry, and connects the work or treatment and the object to be treated.\nA workbench is often used to hold a workpiece steady during work on it.", "Engineering,_Manufacturing": 0.9999270439, "qwen": "Yes"}
{"id": "9209184", "revid": "13467261", "url": "https://en.wikipedia.org/wiki?curid=9209184", "title": "Solder mask", "text": "Solder mask, solder stop mask or solder resist is a thin lacquer-like layer of polymer that is usually applied to the copper traces of a printed circuit board (PCB) for protection against oxidation and to prevent solder bridges from forming between closely spaced solder pads. A solder bridge is an unintended electrical connection between two conductors by means of a small blob of solder. PCBs use solder masks to prevent this from happening. Solder mask is not always used for hand soldered assemblies, but is essential for mass-produced boards that are soldered automatically using reflow or wave soldering techniques. Once applied, openings must be made in the solder mask wherever components are soldered, which is accomplished using photolithography. Solder mask is traditionally green, but is also available in many other colors.\nSolder mask comes in different media depending upon the demands of the application. The lowest-cost solder mask is epoxy liquid that is silkscreened through the pattern onto the PCB. Other types are the liquid photoimageable solder mask (LPSM or LPI) inks and dry-film photoimageable solder mask (DFSM). LPSM can be silkscreened or sprayed on the PCB, exposed to the pattern and developed to provide openings in the pattern for parts to be soldered to the copper pads. DFSM is vacuum-laminated on the PCB then exposed and developed. All three processes typically go through a thermal cure of some type after the pattern is defined although LPI solder masks are also available in ultraviolet (UV) cure.\nThe solder stop layer on a flexible board is also called \"coverlay\" or \"coverfilm\".\nIn electronic design automation, the solder mask is treated as part of the layer stack of the printed circuit board, and is described in individual Gerber files for the top and bottom side of the PCB like any other layer (such as the copper and silk-screen layers). Typical names for these layers include codice_1/codice_2 aka codice_3/codice_4 or codice_5/codice_6 (EAGLE), codice_7/codice_8 (KiCad), codice_9/codice_10 (TARGET), codice_11/codice_12 (Fritzing), codice_13/codice_14 (OrCAD), codice_15/codice_16 (PADS), codice_17/codice_18 (WEdirekt) or codice_19/codice_20 (Gerber and many others).", "Engineering,_Manufacturing": 1.0000064373, "qwen": "Yes"}
{"id": "4577289", "revid": "252195", "url": "https://en.wikipedia.org/wiki?curid=4577289", "title": "Optical manufacturing and testing", "text": "Optical manufacturing and testing spans an enormous range of manufacturing procedures and optical test configurations. \nThe manufacture of a conventional spherical lens typically begins with the generation of the optic's rough shape by grinding a glass blank. This can be done, for example, with ring tools. Next, the lens surface is polished to its final form. Typically this is done by lapping—rotating and rubbing the rough lens surface against a tool with the desired surface shape, with a mixture of abrasives and fluid in between. \nTypically a carved pitch tool is used to polish the surface of a lens. The mixture of abrasive is called slurry and it is typically made from cerium or zirconium oxide in water with lubricants added to facilitate pitch tool movement without sticking to the lens. The particle size in the slurry is adjusted to get the desired shape and finish. \nDuring polishing, the lens may be tested to confirm that the desired shape is being produced, and to ensure that the final shape has the correct form to within the allowed precision. The deviation of an optical surface from the correct shape is typically expressed in fractions of a wavelength, for some convenient wavelength of light (perhaps the wavelength at which the lens is to be used, or a visible wavelength for which a source is available). Inexpensive lenses may have deviations of form as large as several wavelengths (λ, 2λ, etc.). More typical industrial lenses would have deviations no larger than a quarter wavelength (λ/4). Precision lenses for use in applications such as lasers, interferometers, and holography have surfaces with a tenth of a wavelength (λ/10) tolerance or better. In addition to surface profile, a lens must meet requirements for surface quality (scratches, pits, specks, etc.) and accuracy of dimensions.", "Engineering,_Manufacturing": 0.9999953508, "qwen": "Yes"}
{"id": "22929164", "revid": "3596390", "url": "https://en.wikipedia.org/wiki?curid=22929164", "title": "Air Force Logistics Management Agency", "text": "The Air Force Logistics Management Agency (AFLMA) improves agile combat support capabilities by generating enterprise supply chain solutions supporting logistics transformation through research, war games and literature. The agency supports Air Force enterprise logistics transformation by sustaining the Air Force supply chain architecture; producing solutions to logistics problems; designing new and improved concepts, methods and systems; and publishing the Air Force Journal of Logistics and other publications on logistics issues.\nHistory.\nIn late 1975, the Air Force established the Air Force Logistics Management Center at Gunter Air Force Station, Alabama. It was created in response to a need to centrally manage logistics study improvement efforts and concentrate management emphasis on enhancing combat effectiveness. AFLMC was renamed the Air Force Logistics Management Agency (AFLMA) in 1993. Its charter was, and still is, to solve logistics problems. Since its inception, AFLMA has provided a continuing study, analysis, and development capability to the Air Force logistics community. Tackling and solving Air Force logistics problems remains the focus of the Agency today. The Agency has developed strong working relationships with RAND and the Logistics Management Institute. Additionally, the AFLMA has forged partnering and teaming efforts with a variety of other Air Force, public, and private sector organizations.", "Engineering,_Manufacturing": 0.9730354548, "qwen": "Yes"}
{"id": "22936371", "revid": "6277327", "url": "https://en.wikipedia.org/wiki?curid=22936371", "title": "Tolerance coning", "text": "Tolerance coning is the engineering discipline of creating a budget of all tolerances that potentially add/subtract to affect adequacy of a particular parameter. This is particularly critical where stages of design/manufacture precede test/use.\nFor example, when setting a test limit for a measurement on each manufactured item of some type, to assure that no bad items are shipped, the limit must be tighter than the requirement to allow for the worst case sum of measurement inaccuracies (e.g. equipment, test fixture etc.). The design of the item thus has to take into account not only the product requirement but also the test tolerances. The buildup of this budget is tolerance coning.\nElectronics engineers intuitively do tolerance coning and tend to formalise it for critical parameters. However it is also relevant to other engineering disciplines.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "5444747", "revid": "43055613", "url": "https://en.wikipedia.org/wiki?curid=5444747", "title": "Tool and die maker", "text": "Tool and die makers are highly skilled crafters working in the manufacturing industries. Variations on the name include tool maker, toolmaker, die maker, diemaker, mold maker, moldmaker or tool jig and die-maker depending on which area of concentration or industry an individual works in.\nTool and die makers work primarily in toolroom environments—sometimes literally in one room but more often in an environment with flexible, semipermeable boundaries from production work. They are skilled artisans (craftspeople) who typically learn their trade through a combination of academic coursework and with substantial period of on-the-job training that is functionally an apprenticeship. They make jigs, fixtures, dies, molds, machine tools, cutting tools, gauges, and other tools used in manufacturing processes.\nDivisions.\nThe main divisions of the tool & die industry include:\nJob description.\nWorking from engineering drawings developed by the toolmaker, engineers or technologists, tool makers lay out the design on the raw material (usually metal), then cut it to size and shape using manually controlled machine tools (such as lathes, milling machines, grinding machines, and jig grinders), power tools (such as die grinders and rotary tools), and hand tools (such as files and honing stones).\nArt and science (specifically, applied science) are thoroughly intermixed in their work, as they also are in engineering. \nManufacturing engineers and tool and die makers often work in close consultation as part of a manufacturing engineering team. There is often turnover between the careers, as one person may end up working in both at different times of their life, depending on the turns of their particular educational and career path. There was no codified difference between them during the 19th century and earlier parts of the 20th century; it was only after World War II that engineering became a regulated profession exclusively defined by a university or college engineering degree. Both careers require some level of talent in both artistic/artisanal/creative areas and math-and-science areas.\nSince the advent of computing in the manufacturing fields (including CNC, CAD, CAM, and other computer-aided technologies), tool and die makers have increasingly added IT skills to their daily work. Today's tool and die makers are generally required to have all of the traditional skills plus substantial digital skills; these formidable requirements make the field challenging to master.\nTraining.\nAlthough the details of training programs vary, many tool and die makers begin an apprenticeship with an employer, possibly including a mix of classroom training and hands-on experience. Some prior qualifications in basic mathematics, science, engineering science or design and technology can be valuable. Many tool and die makers attend a 4- to 5-year apprenticeship program to achieve the status of a journeyman tool and die maker. Today's employment relationships often differ in name and detail from the traditional arrangement of an apprenticeship, and the terms \"apprentice\" and \"journeyman\" are not always used, but the idea of a period of years of on-the-job training leading to mastery of the field still applies.\nIn the United States, tool and die makers who graduate from NTMA (National Tooling and Machining Association) have gone through 4 years of college courses as well as 10,000 working hours in order to complete their apprenticeship. They are also accredited through the U.S. Department of Labor.\nJig/fixture maker.\nA jig and fixture maker is under the faction of a tool and die maker/toolmaker. The standard differentiation of jigs from fixtures is that a jig guides the tool for the operation being carried out while a fixture simply secures the work. The terms are sometimes used interchangeably. A jig and fixture maker needs to know how to use an assortment of machines to build these devices such as having skills in welding and in some cases the knowledge of wood working equipment, of course with the tool room machining skills.\nThey are often advised by an engineer in building the devices. A wide knowledge of various materials is needed beyond wood and metal such as plastics. They also can create, design and build without engineering plans/bluprints.\nJig/fixture makers gain hands on practical experience while monitoring and making alterations as the manufacturing process is constantly improved and reviewed with/by engineering. They also can be required to make these adjustments without engineering help, depending on the size of the company. Some Jigs and fixtures require electronic and pneumatic actuation, which will involve knowledge/training in these fields as well.\nProperly built jigs and fixtures reduce waste by ensuring perfectly fitting parts. Jigs and fixtures can be as big as a car or be held in hand. Production needs dictate form and function. Jigs, fixtures and gages are needed to maintain quality standards for repeated low and high volume production demands.\nOngoing evolution of computerized design and control technologies, such as CAD/CAM, CNC, PLC, and others, has limited the use of jigs in manufacturing, however all the computer run machines need some sort of clamping fixture for production runs. A common example is that a drill jig is not needed to guide the drill bits to the hole centers if it is done on a CNC, since it is Computer Numerically Controlled. However, fixtures are still needed to hold the part[s] in place for the operation needed. Jigs are currently needed in many areas of manufacturing but mainly for low-volume production.\nTerminology.\nDie making.\nDie making is a subdiscipline of tool making that focuses on making and maintaining dies. This often includes making punches, dies, steel rule dies, and die sets. Precision is essential in die making; punches and die steels must maintain proper clearance to produce parts accurately, and it is often necessary to have components machined with tolerances of less than one thousandth of an inch.\nTool making.\nTool making typically means making tooling used to produce products. Common tooling includes metal forming rolls, cutting tools (such as tool bits and milling cutters), fixtures, or even whole machine tools used to manufacture, hold, or test products during their fabrication. Due to the unique nature of a tool maker's work, it is often necessary to fabricate custom tools or modify standard tools.\nOverlap of die making, tool making, and mold making.\nOne person may be called upon for all of the above activities, and the skills and concepts involved overlap, which is why tool and die making is often viewed as one field and is also why mold making is often viewed as a subset thereof (rather than a totally separate field).\nToolrooms and toolroom methods.\nA toolroom in the original sense of the word is a room where tools are stored; a tool crib. In larger companies, the tools stored there must be checked in and out, and there may be a person assigned to attend the area. In a factory, the toolroom refers to a space where artifacts are made and repaired, particularly tools for use throughout the rest of the factory, jigs for setups, and other parts to assist workers and, as an extension, production. In engineering and manufacturing, toolroom activity is everything related to tool-and-die facilities in contrast to production line activity.\nOriginally a toolroom was literally in one room, but like \"emergency room\", the term has been figuratively extended in both substantive and adjectival senses to all such places and the methods used there, regardless of the physical space. The name was originally styled tool room or tool-room, but toolroom is now the norm in engineering and machining.\nMaking, repairing, and storing tools.\nThe simplest sense of the word \"toolroom\" refers to the storage of tools. A broader use of the term includes reference to a space where tools are made, repaired, inventoried, and/or distributed for use within the factory. This extension of the latter sense reflects the development of greater systemization in manufacturing. During the 19th century, there gradually developed a division of labor whereby the people who made, repaired, kept records of, stored, and retrieved tools were not necessarily the same people who used the tools to do the manufacturing work itself. Examples of such division of labor had existed in prior centuries, but most manufacturing had been done on a craft basis, where there had been no need for the idea of a toolroom separate from the rest of the workshop.\nThe simplest sense above can also be conveyed by the word toolcrib (sometimes styled tool-crib or tool crib).\nTool-and-die facilities and methods.\nIn engineering and manufacturing, a toolroom is everything related to tool-and-die facilities and methods, in contrast to the factory floor and production line activity. For people not familiar with these fields, in order to understand the specialist usage, some explanation is needed:\nWithin the general field of machining there is a rough but recurring division between (a) toolroom practice and (b) production practice (the making of large numbers of duplicate parts). It is the difference between manufacturing itself and the tool-and-die work that is done in support of the manufacturing. Anecdotal examples of similar distinctions can probably be found here and there throughout human history, but as a widespread part of the \"fabric\" of material culture, this distinction (and the terminology with which to talk about it) has evolved since the Industrial Revolution, and most especially since the advent of armory practice and later mass production.\nA good, simplistic way to summarize the change in ideas is to compare the making of a certain product in different time periods. In 1750, a rifle was made in a workshop by a craftsman using hand tools, and if he needed a new tool, it is likely that he would make it himself using the same tools and methods that he would use to make his product, the rifle (smithy, files, woodcarving knives, etc.) This type of craftsmanship can still be done today, but it is expensive in terms of skilled labor time per unit of output, and therefore it implies small total output volume and high unit price. However, today the way to make rifles in large quantity with low unit price is to first do the tool-and-die work (toolroom work) (that is, make, or have someone else make, machine tools, jigs, and fixtures), and then use those specialized tools to mass-produce the rifles in an automated way that involves no toolroom methods.\nAnother example, instead of comparing different centuries, simply compares different methods of toolpath control that could be chosen today: If you need a certain hole location on each part for your drill bit, will you dial it carefully by hand \"many times\" (once for each part produced), or will you dial it carefully by hand \"only once\"—while making a drill jig for subsequent drilling to be quickly and effortlessly guided by?\nThe manufacturing of small batches has often presented the biggest challenge to this division of methods. When only a small batch of output is demanded, will one (a) produce each piece using \"custom\" methods (handcrafting or toolroom-style layout and machining), which drives up unit cost; or (b) maintain the capital-cost-intensive toolroom-production division, which also drives up unit costs in its own ways? In other words, is it worth one's time to make a fixture, and is it worth tying up a drill press's availability by setting it up for dedicated use with that fixture? The drill press may be needed tomorrow for a different part, with a different setup. For 100 parts, the costs of making a fixture and tying up a machine's availability are justified. For 5 parts, maybe one should just make each of the 5 using toolroom-style layout and toolpath control.\nThe evolution of IT and its integration into manufacturing is changing the questions and equations still further. For example, CNC and robotics have led the way to rapid prototyping and instant manufacturing, which shift the toolroom-production division by giving an up-front toolroom investment the flexibility to be quickly and easily used for any product design, with batch size irrelevant.\nIn large corporations there may be a very distinct division of labor between toolroom work and production machining, with different employees for each, whereas job-shop work is often a blend of toolroom work and production work, because each project requires some of both, and the same employees may \"wear each hat\" in sequence.", "Engineering,_Manufacturing": 1.0000030994, "qwen": "Yes"}
{"id": "5451218", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=5451218", "title": "1991–92 European Cup Winners' Cup", "text": "The 1991–92 season of the European Cup Winners' Cup was won by Werder Bremen in the final against Monaco. Both were first-time finalists in the competition.\nDefending champions Manchester United were eliminated by Atlético Madrid in the second round.\nTeams.\nA total of 34 teams participated in the competition.\nNotes\nQualifying round.\nSecond leg.\n\"Odense won 7–0 on aggregate.\"\n\"Tottenham Hotspur won 2–0 on aggregate.\"\nFirst round.\nSecond leg.\n\"Werder Bremen won 11–0 on aggregate.\"\n\"Monaco won 10–1 on aggregate.\"\n\"Atlético Madrid won 8–2 on aggregate.\"\n\"Manchester United won 2–0 on aggregate.\"\n\"3–3 on aggregate; GKS Katowice won on away goals.\"\n\"Club Brugge won 4–0 on aggregate.\"\n\"Ferencváros won 7–3 on aggregate.\"\n\"Galatasaray won 5–1 on aggregate.\"\n\"Baník Ostrava won 4–1 on aggregate.\"\n\"4–4 on aggregate; Ilves won on away goals.\"\n\"2–2 on aggregate; Roma won on away goals.\"\n\"Norrköping won 6–1 on aggregate.\"\n\"Sion won 2–1 on aggregate.\"\n\"Feyenoord won 1–0 on aggregate.\"\n\"Tottenham Hotspur won 2–1 on aggregate.\"\n\"Porto won 4–0 on aggregate.\"\nSecond round.\nSecond leg.\n\"Monaco won 3–1 on aggregate.\"\n\"Atlético Madrid won 4–1 on aggregate.\"\n\"Club Brugge won 4–0 on aggregate.\"\n\"Werder Bremen won 4–2 on aggregate.\"\n\"2–2 on aggregate; Galatasaray won on away goals.\"\n\"Roma won 6–3 on aggregate.\"\n\"0–0 on aggregate; Feyenoord won 5–3 on penalties.\"\n\"Tottenham Hotspur won 3–1 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"4–4 on aggregate. Club Brugge won on away goals.\"\n\"Werder Bremen won 2–1 on aggregate.\"\n\"Monaco won 1–0 on aggregate.\"\n\"Feyenoord won 1–0 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Werder Bremen won 2–1 on aggregate.\"\n\"3–3 on aggregate. Monaco won on away goals.\"\nTop scorers.\nThe top scorers from the 1991–92 UEFA Cup Winners' Cup are as follows:", "Engineering,_Manufacturing": 0.9985639453, "qwen": "Yes"}
{"id": "5456121", "revid": "44097945", "url": "https://en.wikipedia.org/wiki?curid=5456121", "title": "Pancake die", "text": "A pancake die is a simple type of manufacturing die that performs blanking or piercing. Many dies perform complex procedures simultaneously (or progressively for progressive die) such as coining, piercing, forming, bending in addition to product removal and transport (for additional manufacturing procedures or packaging). A pancake die may only perform one simple procedure with the finish product being removed by hand.\nAn example would be a die that performs blanking of round paper gaskets without holes. This type of die would be created in one simple pass from a wire EDM after heat treating. The workpiece would then produce the punch and the die after the cut is complete. Additional work would then include adding a stripper plate to the punch plate after the punch has been mounted (on punch plate). At this point the pancake die is ready for production.", "Engineering,_Manufacturing": 0.9999746084, "qwen": "Yes"}
{"id": "30027235", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=30027235", "title": "Individual wheel drive", "text": "Individual-wheel drive (IWD) is a wheeled vehicle with a drivetrain that allows all wheels to receive torque from several motors independent of each other. The term was coined to identify those electric vehicles whereby each wheel is driven by its own individual electric motor, as opposed to conventional differentials.\nCharacteristics.\nThese vehicles inherently have a range of characteristics built-in that are more commonly attributed to four-wheel drive vehicles or vehicles with extensive control systems. These characteristics can be:\nOther features\nThe motors that are used in these vehicles are commonly wheel hub motors, since no transmission components are then required. Alternative layouts with inboard motors and drive shafts are also possible.\nHydraulic wheel drive.\nHydraulic wheel drives share many of the same features as an electric wheel drive. They also lack the need for a central gear box, mechanical differentials, drive shafts, and provide on the fly switching between front, rear and all-wheel drive. Hydraulic individual wheel drives are standard in various machines, such as zero-turn mowers, multi one lifts / front end loaders, and forklifts. Hydraulic drives are primarily found in machines that serve uses which benefit from the ability to \"turn on a dime\", i.e. with an exceptionally short turning diameter, and move between forward and reverse modes without shifting gears, such as lawn mowers and loading equipment.\nAlthough one may be conflicted in considering such systems as a direct drive system, being that a motorized pump must drive the hydraulic system from a position other than the wheel hub. Nonetheless the drive is provided directly from the hydraulic rotary motor found in or adjacent to the wheel hub.", "Engineering,_Manufacturing": 0.9986811876, "qwen": "Yes"}
{"id": "30031381", "revid": "8349418", "url": "https://en.wikipedia.org/wiki?curid=30031381", "title": "Out of autoclave composite manufacturing", "text": "Out of autoclave composite manufacturing is an alternative to the traditional high pressure autoclave (industrial) curing process commonly used by the aerospace manufacturers for manufacturing composite material. Out of autoclave (OOA) is a process that achieves the same quality as an autoclave but through a different process. OOA curing achieves the desired fiber content and elimination of voids by placing the layup within a closed mold and applying vacuum, pressure, and heat by means other than an autoclave. An RTM press is the typical method of applying heat and pressure to the closed mold. There are several out of autoclave technologies in current use including resin transfer molding (RTM), Same Qualified Resin Transfer Molding (SQRTM), vacuum-assisted resin transfer molding (VARTM), and balanced pressure fluid molding. The most advanced of these processes can produce high-tech net shape aircraft components.\nProcesses.\nResin transfer molding.\nResin transfer molding (RTM) is a method of fabricating high-tech composite structures. The RTM process is capable of consistently producing composite parts with high strength, complex geometries, tight dimensional tolerances, and part quality typically required of aerospace applications.\nRTM uses a closed mold commonly made of aluminum. A fiber \"layup\" such as graphite is placed into the mold. The mold is closed, sealed, heated, and placed under vacuum. Heated resin is injected into the mold to impregnate the fiber layup. Having the mold heated and under vacuum, as in Vacuum Assisted Resin Transfer Molding (VARTM) assists the resin flow. The mold is then held at a temperature sufficient to cure the resin.\nCurrent RTM technology produces lightweight parts with excellent mechanical properties. With these qualities, composite materials are gaining wide use in a variety of structural and non-structural applications common in aerospace and aviation. RTM is one method of fabricating these composite structures.\nSame Qualified Resin Transfer Molding.\nSame Qualified Resin Transfer Molding (SQRTM) is a closed mold composites manufacturing method similar to RTM (Resin Transfer Molding). \"Same Qualified\" refers to this method injecting the same resin as that used in the prepreg layup. The attributes of \"same qualified\" are significant to a manufacturer because those who adopt this process need not re-qualify resin materials for their production process.\nWhat sets SQRTM apart from standard resin transfer molding is the substitution of a prepreg layup rather than a dry fiber preform.\nSQRTM is an RTM process adapted to prepreg technology. The prepreg is placed in a closed mold and during the cure cycle, a small amount of resin is injected into the cavity through ports positioned around the part. This resin does not go into the laminate, but only presses up against the edge of the laminate in order to establish hydrostatic pressure on the prepreg, similar to the goal of autoclave curing. This pressure is similar to the autoclave, on the order of 6-7 bars (90-100 psi). Hydrostatic pressure minimizes voids by keeping dissolved air, water and resin monomers in solution in the resin.\nThe tool can either be self-clamped and self-heated or heated and clamped by a press. The equipment is composed of a tool, a press, an injector, and a vacuum pump.\nThe key factors in the SQRTM process include precision machined closed mold tooling, high pressure presses, a high vacuum applied to the tool interior, and precise control of heating platens, injected resin volume, heat, and pressure.\nThe advantages of the SQRTM process include a high level of integration, tight tolerances and the use of qualified prepregs.\nIts disadvantages include higher tool costs and a lower level of flexibility to design changes.\nVacuum assisted resin transfer molding.\nVacuum assisted resin transfer molding (VARTM) differs from pre-preg processing in that fiber reinforcements and core materials are laid up on a one-sided mold and vacuum bagged. Liquid resin is introduced through ports in the mold and vacuum-drawn through the reinforcements by way of designed-in channels and infusion media that facilitate fiber wetout. Subsequent curing does not require high heat or high pressure, unlike the autoclave. The process's comparatively low-cost tooling allows inexpensive production of large, complex parts in one shot, such as the tail of the Mitsubishi Regional Jet.\nBalanced pressure fluid molding.\nBalanced pressure molding using fluid as the heat transfer is commercially practiced as the 'quickstep' process. This process allows for the curing, partial curing, and joining of composite materials. The process involves a fluid-filled, pressure balanced, heated floating mould technology. The heated floating mold technology used within the process works by rapidly applying heat to the laminate which is trapped between a free floating rigid or semi-rigid mold that floats in, and is surrounded by, a heat transfer fluid (HTF). The rapid heating can lead to significantly lower resin viscosities, and this in turn allows achieving full laminate consolidation using pressures lower than those used in autoclave. The mold and laminate become separated from the circulating HTF by a flexible membrane. The part, typically under full vacuum, is subject to pressures as high as 250kPa fluid pressure and can be rapidly heated to the desired cure temperature without risk of catastrophic exothermic reaction, as the HTF can draw excess heat as desired. The air is then removed under vacuum and the laminate is compacted and heated until the part is cured.\nA flexible membrane beneath the mold is bonded into a pressure chamber creating the lower half of a 'clamshell' or 'chamber' like mold set. A second flexible membrane is bonded to a second pressure chamber creating the upper half of the clamshell. These pressure chambers are clamped together during processing, permitting the laminate to be compressed while reducing stress to the mold as it is floating in a balanced pressure environment within the HTF.\nThe process can use thermosetting, thermoplastic prepregs (pre-impregnated composite fibers), and wet resin with dry fiber to produce superior composite parts. This out of autoclave process can achieve aerospace grade void contents of less than 2%, with extremely fast cycle times, and at significantly lower pressures and lower labor costs than many alternative autoclave production systems using many typical autoclave qualified prepregs. The quickstep out of autoclave system is unique in that it uses fully immersed balanced pressure fluid curing and it allows the user to stop the composite cure reaction at any point in the cure cycle, and thus can halt processing on all or part of the laminate and either return to it at a later to complete cure or to co-cure, join and bond other composites to it to create larger parts.\nThe use of fluid to control temperature, as opposed to the gas generally used within methods such as autoclave and oven curing equates to lower energy consumption, faster cycle times and extremely accurate part temperature control.\nPrepreg compression molding.\nAnother out of autoclave method for achieving external compression on prepreg based composite parts is through the use of heat shrink tape. This method, however, does not achieve the high quality of RTM or autoclave processes because without the autoclave or a closed mold, the part must be cured in a non-pressurized oven. These compression tapes are typically made from polyester (PET) film. Heat shrink tape is applied to a composite part prior to the heating, or curing cycle. When heated, the tape will shrink in the linear (machine direction). Heat shrink tape works best on parts that are cylindrical or semi-circular in cross section, as this allows the tape to exert even compaction forces on the part surface. Examples would be composite tubes for aerospace, wind energy, consumer sporting goods, etc. Heat shrink tape allows these parts to be processed without the need to cure with the heat and pressure of an autoclave.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "30039003", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=30039003", "title": "Fibrenap (Cushy Pads)", "text": "Fibrenap, also referred to as Cushy Pad, is a product made from wood wool bound in Kraft paper which can be used as an environmentally friendly method for packaging a wide range of items. Fibrenap, in its simplest form, comes as a roll of Kraft paper stuffed with wood wool and comes in a variety of widths. These rolls of Fibrenap can be cut to any length desired, wrapped in a plastic sleeve or made into bails. Any combination of these methods can be used to ensure it is in a form which is best suited to the item it is packaging. Fibrenap is most commonly used to transport heavy industry items to protect the items against vibrations and shocks which could occur during transportation.", "Engineering,_Manufacturing": 0.9974684119, "qwen": "Yes"}
{"id": "12601888", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=12601888", "title": "Universal measuring machine", "text": "Universal measuring machines (UMM) are measurement devices used for objects in which geometric relationships are the most critical element, with dimensions specified from geometric locations (see GD&T) rather than absolute coordinates. The very first uses for these machines was the inspection of gauges and parts produced by jig grinding. While bearing some resemblance to a coordinate-measuring machine (CMM) its usage and accuracy envelope differs significantly. While CMMs typically move in three dimensions and measure with a touch probe, a UMM aligns a spindle (4th axis) with a part geometry using a continuous scanning probe.\nOriginally, universal measuring machines were created to fill a need to continuously measure geometric features in both an absolute and comparative capacity, rather than a point based coordinate measuring system. A CMM provides a rapid method for inspecting absolute points, but geometric relationships, such as runout, parallelism, perpendicularity, etc., must be calculated rather than measured directly. By aligning an accurate spindle with an electronic test indicator with a geometric feature of interest, rather than using non-scanning cartesian probe to estimate an alignment, a universal measuring machine fills this need. The indicator can be accurately controlled and moved across a part, either along a linear axis or radially around the spindle, to continuously record profile and determine geometry. This gives the universal machine a very strong advantage over non-scanning measuring methods when profiling flats, radii, contours, and holes, as the detail of the feature can be of at the resolution of the probe. More modern CMMs do have scanning probes and thus can determine geometry similarly. \nIn practice, the 1970s-era universal measuring machine is a very slow machine that requires a highly skilled and patient operator to use, and the accuracy built into these machines far outstripped the needs of most industries. As a result, the universal measuring machine today is uncommon, only found as a special-purpose machine in metrology laboratories. Because the machine can make comparative length measurements without moving linear axes, it is a valuable tool in comparing master gauges and length standards. While universal measuring machines were never a mass-produced item, they are no longer available on a production basis, and are produced on a to-order basis tailored to the needs of the metrology lab purchasing it. Manufacturers that perform work that must be measured on such a machine will frequently opt to subcontract the measurement to a laboratory which specializes in such.\nUniversal measuring machines placed under corrected interferometric control and using non-contact gauge heads can measure features to millionths of an inch across the entire machine's envelope, where other types of machine are limited either in number of axes or accuracy of the measurement. The accuracy of the machine itself is negligible, as the environment the machine is the limiting factor to effective accuracy. The earlier mechanical machines were built to hold 10 to 20 millionths of an inch accuracy across the entire machine envelope, and due to incredible machine design and forethought, remain as accurate today without computer compensation.", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "61186813", "revid": "45948804", "url": "https://en.wikipedia.org/wiki?curid=61186813", "title": "Cold spray additive manufacturing", "text": "Cold spray additive manufacturing (CSAM) (also called cold spray 3D printing) is a particular application of cold spraying, able to fabricate freestanding parts or to build features on existing components. During the process, fine powder particles are accelerated in a high-velocity compressed gas stream, and upon the impact on a substrate or backing plate, deform and bond together creating a layer. Moving the nozzle over a substrate repeatedly, a deposit is building up layer-by-layer, to form a part or component. If an industrial robot or computer controlled manipulator controls the spray gun movements, complex shapes can be created. To achieve 3D shape, there are two different approaches. First to fix the substrate and move the cold spray gun/nozzle using a robotic arm, the second one is to move the substrate with a robotic arm, and keep the spray-gun nozzle fixed. There is also a possibility to combine these two approaches either using two robotic arms or other manipulators. The process always requires a substrate and uses only powder as raw material.\nThis technique is distinct from selective laser melting or electron-beam additive manufacturing or other additive manufacturing process using laser or electron beam for melting the feedstock materials.\nHistory.\nThe origins of the cold spray process go back to the beginning of the 20th century, when it was developed and patented by Thurston.\nThe process was further investigated by in the 1950s by Rocheville and was re-discovered in the 1980s at the Institute of Theoretical and Applied Mechanics of the Russian Academy of Science and developed as a coating technology. The process started to be employed for additive repair and fabrication of freeform structures, that can be considered as additive manufacturing, at the beginning of the 21st century, when the first commercial cold spray system was introduced in the market.\nProcess.\nAdditive manufacturing employing the process of cold spraying and its benefits can be considered as a deposition process, capable to build freeform parts and structures at high rates. Since it is a solid-state coating deposition process, during the process no melting of the feedstock material (metal powder) occurs, there are no heat related distortion and no protective atmosphere required, which enables to build up structures layer-by-layer. Theoretically, it allows for manufacture without size limitations for fabricating individual components or repairing damaged components.\nThe largest 3D printer or Additive Manufacturing machine utilizing cold spray can build parts up to 9×3×1.5 m. During the cold spray process, the impacting particles create the layer, whose thickness can differ, based on the spray gun travel speed against the substrate and the feedstock material feed rate, building the structure layer-by-layers.\nMaterials.\nIn cold spraying, the principle of the process is based on plastic deformation of the feedstock powder particles, therefore it is suitable to deposit with this technique mainly pure metals and alloys, but also metallic glasses, metal matrix composites and in some cases polymers. The research and development activities recently focusing on a few most challenging materials for the aircraft, space and defence industry such as aluminum alloys, Nickel base superalloys, different steel grades and titanium alloys\nApplications.\nTool and mould making.\nForming, casting and stamping tools with conformal cooling and heating conducting elements, enabling shorter cycle times and significantly longer lifetime of these tools\nDefence applications.\nTitanium drones, Titomic built a 1.8 meter quadcopter at their R&D Bureau in Melbourne, Australia using their version CSAM. The article also talks about Titomic being contracted to make test parts for Boeing.\nDifference from other AM methods.\nThe most significant differences between the Cold Spray Additive Manufacturing process and other additive manufacturing processes are the low temperature, solid state of the process, avoiding melting the feedstock material.\nSee also.\n3D printing\nElectron-beam freeform fabrication\nSelective laser sintering\nSelective laser melting", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "61186819", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=61186819", "title": "Smart Metrology", "text": "Smart Metrology is the modern approach to industrial metrology. The name was introduced by Jean-Michel Pou and Laurent Leblond, a French meteorologist and a French statistician. The term was coined in their book \"La Smart Metrology: De la métrologie des instruments... à la métrologie des décisions\". It was immediately adopted by Deltamu, a French company providing services in the field of industrial metrology, to promote its vision of metrology.\nThe modern approach promoted by Smart Metrology consists, mainly, in the full exploitation of all available data and information, including that provided by Big Data, to implement a correct, pertinent and efficient approach to the three pillars of metrology (uncertainty, calibration and traceability) in the industrial applications\nThe Smart Metrology approach.\nThe approach suggested by Smart Metrology is fully framed inside the ISO 9001 recommendations that any industry using a measuring instrument must keep them under control.\nThe traditional approach.\nThe traditional approach to industrial metrology tends to follow these steps:\nSo, the actual results of the calibration may not even be used in the decision-making process. This way, metrology is often regarded as a pure cost and is actually not following the ISO 9001 quality standards.\nSmart metrology innovation.\nSmart metrology follows a different approach to keeping the instruments under control. This new approach is aimed at achieving a higher efficiency according to the following steps:\nAccording to the above steps, metrology does no longer represent an useless cost, afforded mainly to satisfy the standards. Instead, it can be regarded as an investment to enhance the quality of industrial production. It makes full use of the measurement results and makes use of measurement uncertainty in the decision-making process.", "Engineering,_Manufacturing": 0.9877810478, "qwen": "Yes"}
{"id": "42541439", "revid": "26785110", "url": "https://en.wikipedia.org/wiki?curid=42541439", "title": "Closed-loop manufacturing", "text": "Closed-loop manufacturing (abbreviated CLM) is a closed-loop process of manufacturing and measuring (checking) in the manufacturing machine. The pre-stage to this is inspection in manufacturing. The idea is to reduce costs and improve the quality and accuracy of the produced parts.\nGeneral procedure.\nClosed-loop manufacturing can be done in different ways dependent on the manufacturing technique and on the accuracy requirements.\nSuitable manufacturing techniques.\nCLM is very suitable for electrical discharge machining. Milling or turning is also suitable for CLM.\nSuitable measuring techniques.\nIn machining measurement techniques have to fulfill special needs. In particular optical techniques have the advantage that they do not touch the part. The following parts are practically used:\nAdvantages / Disadvantages.\nThe advantages are:\nThe disadvantages are:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "42565186", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=42565186", "title": "The Printhouse", "text": "The Printhouse is an American company headquartered in the Chicago suburb of Palatine, Illinois. The Printhouse was formed when a company, Qualay International changed names in 1995 to The Printhouse. They are a provider of commercial printing and paperboard packaging. The Printhouse has designed a unique, fully online proofing system. This proofing method includes QR codes.\nIndustries Served.\nPublishing, logistics, manufacturing, educational testing, church pension, transportation, automotive parts, fitness, oil & refining, advertising, heating and air-conditioning, financial planning, insurance, legal, accounting, wedding gowns, floral wholesale, banking.", "Engineering,_Manufacturing": 0.9999748468, "qwen": "Yes"}
{"id": "6077301", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=6077301", "title": "MSC Industrial Direct", "text": "MSC Industrial Direct Co., Inc (MSC), through its subsidiaries, primarily, MSC Industrial Supply Co., it is one of the largest industrial equipment distributors in the United States, distributing more than 1.5 million metalworking and other industrial products. \nMSC was founded in 1941 as Sid Tool, Inc., by Sidney Jacobson, in New York's Little Italy. It originally sold cutting tools and accessories to New York City machine shops. The company later moved its headquarters to Plainview, NY. \nIn 1970, Manhattan Supply Company was acquired and, in 1998, moved its headquarters to Melville, New York. The company currently operates from five regional Customer Fulfillment Centers and 12 branch offices.\nOn June 8, 2006, MSC completed the acquisition of J & L America, Inc. DBA J & L Industrial Supply (J & L), a subsidiary of Kennametal, for $349.5 million.\nIn 2013, Erik Gershwind, Sid Jacobson's grandson, was named President and Chief Executive Officer. In 2013 the company opened its co-headquarters office in Davidson, North Carolina which is located in the Charlotte, North Carolina metropolitan area. The company has expanded to 750 employees at the co-headquarters, with 120 employees making the move to the Carolinas from the Melville office.\nIn 2013, MSC acquired Barnes Distribution North America to expand its footprint in Canada. The business was renamed Class C Solutions Group.\nIn 2017, MSC acquired DECO Tool Supply Co., an industrial supply distributor based in Davenport, Iowa, to expand its footprint in the region.\nIn 2018, MSC acquired All Integrated Solutions, a value-added distributor of industrial fasteners and components, MRO supplies and assembly tools based in Franksville, Wisconsin.\nIn 2019, MSC completed a transaction with TAC Global Solutions, a Mexican industrial distribution company, to expand into Mexico.\nIn 2022, MSC acquired Engman-Taylor, a Menomonee Falls, Wisconsin-based distributor of metalworking tools and supplies. That same year, MSC also acquired Tower Fasteners, a Holtsville, New York-based valued-added distributor of Original Equipment Manufacturer (OEM) fasteners and components.\nIn 2023, MSC acquired Buckeye Industrial Supply Co., an independent metalworking distributor based in Columbus, Ohio, and Tru-Edge Grinding Inc., a St. Henry, Ohio-based custom tool manufacturer.", "Engineering,_Manufacturing": 0.9995025396, "qwen": "Yes"}
{"id": "6079682", "revid": "45461882", "url": "https://en.wikipedia.org/wiki?curid=6079682", "title": "Susceptor", "text": "A susceptor is a material used for its ability to absorb electromagnetic energy and convert it to heat (which in some cases is re-emitted as infrared thermal radiation). The electromagnetic energy is typically radiofrequency or microwave radiation used in industrial heating processes, and also in microwave cooking.\nOperation.\nIn microwave cooking, susceptors are built into paper packaging of certain foods, where they absorb microwaves which penetrate the packaging. This process raises the susceptor patch temperature to levels where it may then heat food by conduction or by infrared radiation.\nDesign and use.\nSusceptors are usually made of metallised film, ceramics or metals (such as aluminium flakes).\nThe susceptor (which may be located on examination by its gray or blue-gray color, which is different from paper) is the reason products meant to be browned via susceptor-generated thermal radiation carry instructions to microwave the food while still inside its packaging.\nSusceptors meant to heat foods by direct conduction, where less browning will occur, may be seen in the gray lining of packaging directly holding the food and in good contact with it. A typical example of the latter is the paper-susceptor–lined dish directly holding a microwaveable pot pie or casserole.\nSusceptors built into packaging create high temperatures in a microwave oven. This is useful for crisping and browning foods, as well as concentrating heat on the oil in a microwave popcorn bag (which is solid at room temperature) in order to melt it rapidly.\nAmong the first microwave susceptors marketed were those from the mid-1980s in a product called McCain Micro Chips by McCain Foods. It consisted of a susceptor sheet which cooked French fries in a microwave oven. These sheets are currently used in several types of packaging for heating and cooking products in microwave ovens. Care in package design and use is required for proper food safety.\nA \"crisping sleeve\" is a device made of paperboard and affixed with a susceptor used both as a rigid container to support the food items within and to focus heat on the foodstuff. They are generally intended for a single use. Hot Pockets is an example of a product which uses crisping sleeves.\nMicrowave crisper pan.\nMicrowave crisper pans and trays covert microwave into infrared to heat food.", "Engineering,_Manufacturing": 0.9998971224, "qwen": "Yes"}
{"id": "23336505", "revid": "14383484", "url": "https://en.wikipedia.org/wiki?curid=23336505", "title": "2009–10 UEFA Europa League qualifying phase and play-off round", "text": "This article details the 2009–10 UEFA Europa League qualifying phase and play-off round.\nAll times CEST (UTC+2)\nTeams.\nThis table shows the path of all 174 teams involved in the qualifying phase and play-off round, including the 15 losing teams from the Champions League third qualifying round which joined at the play-off round (marked by CL). 38 teams qualified for the group stage to join the 10 losing teams from the Champions League play-off round.\nCL-c Losing teams from the Champions League third qualifying round (Champions Path)\nCL-n Losing teams from the Champions League third qualifying round (Non-Champions Path)\nFirst qualifying round.\nSeeding.\nTeams with a coefficient of at least 1.332 were seeded.\nMatches.\nNotes:\nFirst leg.\nNotes\nSecond leg.\n\"Zimbru Chișinău won 3–2 on aggregate.\"\n\"Zestaponi won 11–1 on aggregate.\"\n\"Helsingborg won 4–2 on aggregate.\"\n\"Haladás 2–2 Irtysh on aggregate. Haladás won on away goals.\"\n\"Spartak Trnava won 5–2 on aggregate.\"\n\"MTZ-RIPO won 3–2 on aggregate.\"\n\"Dinamo Minsk won 3–2 on aggregate.\"\n\"Bnei Yehuda won 4–0 on aggregate.\"\n\"Dinaburg won 2–1 on aggregate.\"\n\"Slaven Belupo won 1–0 on aggregate.\"\n\"Olimpi Rustavi won 4–0 on aggregate.\"\n\"Lahti won 4–3 on aggregate.\"\n\"FK Vėtra won 6–0 on aggregate.\"\n\"Rosenborg won 6–1 on aggregate.\"\n\"Rudar Velenje won 6–1 on aggregate.\"\n\"Anorthosis Famagusta won 7–1 on aggregate.\"\n\"Vllaznia Shkodër won 3–2 on aggregate.\"\n\"Fram won 4–2 on aggregate.\"\n\"Motherwell won 3–1 on aggregate.\"\n\"Široki Brijeg won 2–1 on aggregate.\"\n\"Polonia Warsaw won 2–1 on aggregate.\"\n\"Randers won 7–0 on aggregate.\"\n\"Valletta won 5–2 on aggregate.\"\nNotes\nSecond qualifying round.\nSeeding.\nTeams with a coefficient of at least 1.958 were seeded, except Lahti, the lowest ranked of the teams from Finland.\nMatches.\nNotes:\nFirst leg.\nNotes\nSecond leg.\n\"Legia Warsaw won 4–0 on aggregate.\"\n\"Dinamo Tbilisi won 4–3 on aggregate.\"\n\"Karabakh won 1–0 on aggregate.\"\n\"Metalurh Donetsk won 5–1 on aggregate.\"\n\"Rabotnički won 5–3 on aggregate.\"\n\"Petrovac won 4–3 on aggregate.\"\n\"NAC Breda won 8–0 on aggregate.\"\n\"Lahti won 2–1 on aggregate.\"\n\"St Patrick's Athletic won 2–1 on aggregate.\"\n\"Brøndby won 4–2 on aggregate.\"\n\"Kaunas 1–1 Sevojno on aggregate. Sevojno won on away goals.\"\n\"Polonia Warsaw won 5–0 on aggregate.\"\n\"Bnei Yehuda won 5–0 on aggregate.\"\n\"FK Vėtra won 3–2 on aggregate.\"\n\"MŠK Žilina won 3–0 on aggregate.\"\n\"Elfsborg won 3–0 on aggregate.\"\n\"Tromsø won 4–1 won aggregate.\"\n\"Randers won 2–1 on aggregate.\"\n\"Basel won 7–1 on aggregate.\"\n\"Maccabi Netanya won 3–0 on aggregate.\"\n\"Slaven Belupo won 12–2 on aggregate.\"\n\"KR won 3–1 on aggregate.\"\n\"Cherno More won 4–0 on aggregate.\"\n\"Sarajevo won 2–1 on aggregate.\"\n\"Vaduz won 2–1 on aggregate.\"\n\"Steaua București won 4–1 on aggregate.\"\n\"Derry City won 2–1 on aggregate.\"\n\"Omonia won 8–1 on aggregate.\"\n\"Gent 2–2 Naftan on aggregate. Gent won on away goals.\"\n\"Galatasaray won 3–1 on aggregate.\"\n\"Rapid Wien won 8–0 on aggregate.\"\n\"Sturm Graz won 3–2 on aggregate.\"\n\"Slavija won 3–1 on aggregate.\"\n\"Red Star Belgrade won 5–0 on aggregate.\"\n\"Motherwell won 8–2 on aggregate.\"\n\"Helsingborg won 4–3 on aggregate.\"\n\"Sigma Olomouc won 3–1 on aggregate.\"\n\"Rijeka won 3–1 on aggregate.\"\n\"Honka won 3–0 on aggregate.\"\n\"Paços de Ferreira won 1–0 on aggregate.\"\nNotes\nThird qualifying round.\nSeeding.\nTeams with a coefficient of at least 7.826 were seeded. Karabakh, Petrovac and Slavija were also seeded because the draw was held before the second qualifying round, in which they beat teams who would have been seeded.\nMatches.\nNotes\nFirst leg.\nNotes\nSecond leg.\n\"Vaslui won 3–1 on aggregate.\"\n\"Krylia Sovetov 3–3 St Patrick's Athletic on aggregate. St Patrick's Athletic won on away goals.\"\n\"Karabakh won 3–1 on aggregate.\"\n\"Košice won 5–1 on aggregate.\"\n\"Slovan Liberec won 3–0 on aggregate.\"\n\"PSV won 2–0 on aggregate.\"\n\"Lech Poznań won 7–3 on aggregate.\"\n\"Hapoel Tel Aviv won 4–2 on aggregate.\"\n\"Tromsø won 4–1 on aggregate.\"\n\"Club Brugge won 4–3 on aggregate.\"\n\"Lille won 4–0 on aggregate.\"\n\"Sturm Graz won 7–1 on aggregate.\"\n\"Rapid Wien won 4–3 on aggregate.\"\n\"Austria Wien won 5–3 on aggregate.\"\n\"Basel won 5–3 on aggregate.\"\n\"Young Boys 2–2 Athletic Bilbao on aggregate. Athletic Bilbao won on away goals.\"\n\"Galatasaray won 10–1 on aggregate.\"\n\"Legia Warsaw 3–3 Brøndby on aggregate. Brøndby won on away goals.\"\n\"CSKA Sofia won 2–1 on aggregate.\"\n\"Metalurh Donetsk won 5–0 on aggregate.\"\n\"NAC Breda won 4–1 on aggregate.\"\n\"Fenerbahçe won 6–2 on aggregate.\"\n\"Sigma Olomouc won 8–1 on aggregate.\"\n\"Metalist Kharkiv won 4–1 on aggregate.\"\n\"Elfsborg won 4–1 on aggregate.\"\n\"Odense won 7–3 on aggregate.\"\n\"Sarajevo 3–3 Helsingborg on aggregate. Sarajevo won 5–4 on penalties.\"\n\"Hamburg won 4–1 on aggregate.\"\n\"Roma won 10–2 on aggregate.\"\n\"PAOK 2–2 Vålerenga on aggregate. PAOK won on away goals.\"\n\"Steaua București won 6–1 on aggregate.\"\n\"Red Star Belgrade won 5–4 on aggregate.\"\n\"MŠK Žilina won 2–1 on aggregate.\"\n\"Fulham won 6–0 on aggregate.\"\n\"Bnei Yehuda won 2–0 on aggregate.\"\nNotes\nPlay-off round.\nSeeding.\nTeams with a coefficient of at least 12.890 were seeded.\nMatches.\nNotes\nFirst leg.\nNotes\nSecond leg.\n\"Shakhtar Donetsk won 5–0 on aggregate.\"\n\"Werder Bremen won 8–3 on aggregate.\"\n\"Fulham won 3–2 on aggregate.\"\n\"Twente won 3–1 on aggregate.\"\n\"Hapoel Tel Aviv won 3–2 on aggregate.\"\n\"CSKA Sofia won 2–1 on aggregate.\"\n\"Everton won 5–1 on aggregate.\"\n\"Hertha BSC won 4–3 on aggregate.\"\n\"Ajax won 7–1 on aggregate.\"\n\"Nacional won 5–4 on aggregate.\"\n\"CFR Cluj won 3–2 on aggregate.\"\n\"Heerenveen 1–1 PAOK on aggregate. Heerenveen won on away goals.\"\n\"Lille won 6–3 on aggregate.\"\n\"Lazio won 3–1 on aggregate.\"\n\"Athletic Bilbao won 4–3 on aggregate.\"\n\"Sturm Graz won 2–1 on aggregate.\"\n\"Austria Wien won 5–4 on aggregate.\"\n\"Dinamo București 3–3 Slovan Liberec on aggregate. Dinamo București won 9–8 on penalties.\"\n\"Partizan won 3–1 on aggregate.\"\n\"Basel won 8–2 on aggregate.\"\n\"AEK Athens won 4–2 on aggregate.\"\n\"Galatasaray won 6–1 on aggregate.\"\n\"BATE Borisov won 4–1 on aggregate.\"\n\"Sparta Prague won 3–0 on aggregate.\"\n\"Villarreal won 9–2 on aggregate.\"\n\"Lech Poznań 1–1 Club Brugge on aggregate. Club Brugge won 4–3 on penalties.\"\n\"Slavia Prague won 4–2 on aggregate.\"\n\"Hamburg won 8–2 on aggregate.\"\n\"Fenerbahçe won 4–2 on aggregate.\"\n\"Genoa won 4–2 on aggregate.\"\n\"Dinamo Zagreb won 4–2 on aggregate.\"\n\"Roma won 10–4 on aggregate.\"\n\"PSV won 2–0 on aggregate.\"\n\"Benfica won 5–2 on aggregate.\"\n\"Steaua București won 5–1 on aggregate.\"\n\"Rapid Wien 2–2 Aston Villa on aggregate. Rapid Wien won on away goals.\"\n\"Toulouse won 3–2 on aggregate.\"\n\"Valencia won 7–1 on aggregate.\"\nNotes", "Engineering,_Manufacturing": 0.9983605146, "qwen": "Yes"}
{"id": "2027920", "revid": "44562786", "url": "https://en.wikipedia.org/wiki?curid=2027920", "title": "Blow molding", "text": "Blow molding (or moulding) is a manufacturing process for forming hollow plastic parts. It is also used for forming glass bottles or other hollow shapes.\nIn general, there are three main types of blow molding: extrusion blow molding, injection blow molding, and injection stretch blow molding.\nThe blow molding process begins with softening plastic by heating a preform or parison. The parison is a tube-like piece of plastic with a hole in one end through which compressed air can enter.\nThe plastic workpiece is then clamped into a mold and air is blown into it. The air pressure inflates the plastic which conforms to the mold. Once the plastic has cooled and hardened the mold opens and the part is ejected. Water channels within the mold assist cooling.\nHistory.\nThe process principle comes from the idea of glassblowing. Enoch Ferngren and William Kopitke produced a blow molding machine and sold it to Hartford Empire Company in 1938. This was the beginning of the commercial blow molding process. During the 1940s the variety and number of products were still very limited and therefore blow molding did not take off until later. Once the variety and production rates went up the number of products created soon followed.\nThe technical mechanisms needed to produce hollow-bodied workpieces using the blowing technique were established very early on. Because glass is very breakable, after the introduction of plastic, plastic was used to replace glass in some cases. The first mass production of plastic bottles was done in America in 1939. Germany started using this technology a little bit later but is currently one of the leading manufacturers of blow molding machines.\nIn the United States soft drink industry, the number of plastic containers went from zero in 1977 to ten billion pieces in 1999. Today, an even greater number of products are blown and it is expected to keep increasing.\nFor amorphous metals, also known as bulk metallic glasses, blow molding has been recently demonstrated under pressures and temperatures comparable to plastic blow molding.\nTypologies.\nExtrusion blow molding.\nIn extrusion blow molding, plastic is melted and extruded into a hollow tube forming a tube like piece of plastic with a hole in one end for compressed gas - known as a parison. The parison is captured by closing it into a cooled metal mold. Air is blown into the parison, inflating it into the shape of the hollow bottle, container, or part. After the plastic has cooled, the mold is opened and the part is ejected.\n\"Straight extrusion blow molding is a way of propelling material forward similar to injection molding whereby an Archimedean screw turns, feeding plastic material down a heated tube. Once the plastic is meleted the screw stops rotating and linearly moves to push the melt out. With the accumulator method, an accumulator gathers melted plastic and after the previous mold has cooled and enough plastic has accumulated, a rod pushes the melted plastic and forms the parison. In this case the screw may turn continuously or intermittently. With continuous extrusion the weight of the parison drags the parison and makes calibrating the wall thickness difficult. The accumulator head or reciprocating screw methods use hydraulic systems to push the parison out quickly reducing the effect of the weight and allowing precise control over the wall thickness by adjusting the die gap with a parison programming device.\nContinuous extrusion equipment includes rotary wheel blow molding systems and shuttle machinery, while intermittent extrusion machinery includes reciprocating screw machinery and accumulator head machinery.\nSpin trimming.\nContainers such as jars often have an excess of material due to the molding process. This is trimmed off by spinning a cutting blade around the container which separates the material. The excess plastic is then recycled to create new moldings. Spin Trimmers are used on a number of materials, such as PVC, HDPE and PE+LDPE. Different types of the materials have their own physical characteristics affecting trimming. For example, moldings produced from amorphous materials are much more difficult to trim than crystalline materials. Titanium nitride-coated blades are often used rather than standard steel to increase life by a factor of 30 times.\nInjection blow molding.\nThe process of injection blow molding (IBM) is used for the production of hollow glass and plastic objects in large quantities. In the IBM process, the polymer is injection molded onto a core pin; then the core pin is rotated to a blow molding station to be inflated and cooled. This is the least-used of the three blow molding processes, and is typically used to make small medical and single serve bottles. The process is divided into three steps: injection, blowing and ejection.\nThe injection blow molding machine is based on an extruder barrel and screw assembly which melts the polymer. The molten polymer is fed into a hot runner manifold where it is injected through nozzles into a heated cavity and core pin. The cavity mold forms the external shape and is clamped around a core rod which forms the internal shape of the preform. The preform consists of a fully formed bottle/jar neck with a thick tube of polymer attached, which will form the body. similar in appearance to a test tube with a threaded neck.\nThe preform mold opens and the core rod is rotated and clamped into the hollow, chilled blow mold. The end of the core rod opens and allows compressed air into the preform, which inflates it to the finished article shape.\nAfter a cooling period the blow mold opens and the core rod is rotated to the ejection position. The finished article is stripped off the core rod and as an option can be leak-tested prior to packing. The preform and blow mold can have many cavities, typically three to sixteen depending on the article size and the required output. There are three sets of core rods, which allow concurrent preform injection, blow molding and ejection.\nInjection stretch blow molding.\nInjection Stretch Blow Molding has two main different methods, namely Single-stage and Double-stage process. The Single-stage process is then again broken down into 3-station and 4-station machines.\nSingle-Stage.\nIn the single-stage process, both preform manufacture and bottle blowing is performed in the same machine. The older 4-station method of injection, reheat, stretch blow and ejection is more costly than the 3-station machine which eliminates the reheat stage and uses latent heat in the preform, thus saving costs of energy to reheat and 25% reduction in tooling. The process explained: Imagine the molecules are small round balls, when together they have large air gaps and small surface contact, by first stretching the molecules vertically then blowing to stretch horizontally the biaxial stretching makes the molecules a cross shape. These \"crosses\" fit together leaving little space as more surface area is contacted thus making the material less porous and increasing barrier strength against permeation. This process also increases the strength to be ideal for filling with carbonated drinks.\nTwo-stage.\nIn the two-stage injection stretch blow molding process, the plastic is first molded into a \"preform\" using the injection molding process. These preforms are produced with the necks of the bottles, including threads (the \"finish\") on one end. These preforms are packaged, and fed later (after cooling) into a reheat stretch blow molding machine. In the ISBM process, the preforms are heated (typically using infrared heaters) above their glass transition temperature, then blown using high-pressure air into bottles using metal blow molds. The preform is always stretched with a core rod as part of the process.", "Engineering,_Manufacturing": 0.9999750853, "qwen": "Yes"}
{"id": "1146", "revid": "1162157986", "url": "https://en.wikipedia.org/wiki?curid=1146", "title": "Assembly line", "text": "An assembly line is a manufacturing process (often called a \"progressive assembly\") in which parts (usually interchangeable parts) are added as the semi-finished assembly moves from workstation to workstation where the parts are added in sequence until the final assembly is produced. By mechanically moving the parts to the assembly work and moving the semi-finished assembly from work station to work station, a finished product can be assembled faster and with less labor than by having workers carry parts to a stationary piece for assembly.\nAssembly lines are common methods of assembling complex items such as automobiles and other transportation equipment, household appliances and electronic goods.\nWorkers in charge of the works of assembly line are called assemblers.\nConcepts.\nAssembly lines are designed for the sequential organization of workers, tools or machines, and parts. The motion of workers is minimized to the extent possible. All parts or assemblies are handled either by conveyors or motorized vehicles such as forklifts, or gravity, with no manual trucking. Heavy lifting is done by machines such as overhead cranes or forklifts. Each worker typically performs one simple operation unless job rotation strategies are applied.\nAccording to Henry Ford:\nDesigning assembly lines is a well-established mathematical challenge, referred to as an assembly line balancing problem. In the simple assembly line balancing problem the aim is to assign a set of tasks that need to be performed on the workpiece to a sequence of workstations. Each task requires a given task duration for completion. The assignment of tasks to stations is typically limited by two constraints: (1) a precedence graph which indicates what other tasks need to be completed before a particular task can be initiated (e.g. not putting in a screw before drilling the hole) and (2) a cycle time which restricts the sum of task processing times which can be completed at each workstation before the work-piece is moved to the next station by the conveyor belt. Major planning problems for operating assembly lines include supply chain integration, inventory control and production scheduling.\nSimple example.\nConsider the assembly of a car: assume that certain steps in the assembly line are to install the engine, install the hood, and install the wheels (in that order, with arbitrary interstitial steps); only one of these steps can be done at a time. In traditional production, only one car would be assembled at a time. If engine installation takes 20 minutes, hood installation takes five minutes, and wheels installation takes 10 minutes, then a car can be produced every 35 minutes.\nIn an assembly line, car assembly is split between several stations, all working simultaneously. When a station is finished with a car, it passes it on to the next. By having three stations, three cars can be operated on at the same time, each at a different stage of assembly.\nAfter finishing its work on the first car, the engine installation crew can begin working on the second car. While the engine installation crew works on the second car, the first car can be moved to the hood station and fitted with a hood, then to the wheels station and be fitted with wheels. After the engine has been installed on the second car, the second car moves to the hood assembly. At the same time, the third car moves to the engine assembly. When the third car's engine has been mounted, it then can be moved to the hood station; meanwhile, subsequent cars (if any) can be moved to the engine installation station.\nAssuming no loss of time when moving a car from one station to another, the longest stage on the assembly line determines the throughput (20 minutes for the engine installation) so a car can be produced every 20 minutes, once the first car taking 35 minutes has been produced.\nHistory.\nBefore the Industrial Revolution, most manufactured products were made individually by hand. A single craftsman or team of craftsmen would create each part of a product. They would use their skills and tools such as files and knives to create the individual parts. They would then assemble them into the final product, making cut-and-try changes in the parts until they fit and could work together (craft production).\nDivision of labor was practiced in China, where state-run monopolies mass-produced metal agricultural implements, china, armor, and weapons centuries before mass production appeared in Europe on the eve of the Industrial Revolution. Adam Smith discussed the division of labour in the manufacture of pins at length in his book \"The Wealth of Nations\" (published in 1776).\nThe Venetian Arsenal, dating to about 1104, operated similar to a production line. Ships moved down a canal and were fitted by the various shops they passed. At the peak of its efficiency in the early 16th century, the Arsenal employed some 16,000 people who could apparently produce nearly one ship each day and could fit out, arm, and provision a newly built galley with standardized parts on an assembly-line basis. Although the Arsenal lasted until the early Industrial Revolution, production line methods did not become common even then.\nIndustrial Revolution.\nThe Industrial Revolution led to a proliferation of manufacturing and invention. Many industries, notably textiles, firearms, clocks and watches, horse-drawn vehicles, railway locomotives, sewing machines, and bicycles, saw expeditious improvement in materials handling, machining, and assembly during the 19th century, although modern concepts such as industrial engineering and logistics had not yet been named.\nThe automatic flour mill built by Oliver Evans in 1785 was called the beginning of modern bulk material handling by Roe (1916). Evans's mill used a leather belt bucket elevator, screw conveyors, canvas belt conveyors, and other mechanical devices to completely automate the process of making flour. The innovation spread to other mills and breweries.\nProbably the earliest industrial example of a linear and continuous assembly process is the Portsmouth Block Mills, built between 1801 and 1803. Marc Isambard Brunel (father of Isambard Kingdom Brunel), with the help of Henry Maudslay and others, designed 22 types of machine tools to make the parts for the rigging blocks used by the Royal Navy. This factory was so successful that it remained in use until the 1960s, with the workshop still visible at HM Dockyard in Portsmouth, and still containing some of the original machinery.\nOne of the earliest examples of an almost modern factory layout, designed for easy material handling, was the Bridgewater Foundry. The factory grounds were bordered by the Bridgewater Canal and the Liverpool and Manchester Railway. The buildings were arranged in a line with a railway for carrying the work going through the buildings. Cranes were used for lifting the heavy work, which sometimes weighed in the tens of tons. The work passed sequentially through to erection of framework and final assembly.\nThe first flow assembly line was initiated at the factory of Richard Garrett & Sons, Leiston Works in Leiston in the English county of Suffolk for the manufacture of portable steam engines. The assembly line area was called 'The Long Shop' on account of its length and was fully operational by early 1853. The boiler was brought up from the foundry and put at the start of the line, and as it progressed through the building it would stop at various stages where new parts would be added. From the upper level, where other parts were made, the lighter parts would be lowered over a balcony and then fixed onto the machine on the ground level. When the machine reached the end of the shop, it would be completed.\nInterchangeable parts.\nDuring the early 19th century, the development of machine tools such as the screw-cutting lathe, metal planer, and milling machine, and of toolpath control via jigs and fixtures, provided the prerequisites for the modern assembly line by making interchangeable parts a practical reality.\nLate 19th-century steam and electric conveyors.\nSteam-powered conveyor lifts began being used for loading and unloading ships some time in the last quarter of the 19th century. Hounshell (1984) shows a sketch of an electric-powered conveyor moving cans through a filling line in a canning factory.\nThe meatpacking industry of Chicago is believed to be one of the first industrial assembly lines (or disassembly lines) to be utilized in the United States starting in 1867. Workers would stand at fixed stations and a pulley system would bring the meat to each worker and they would complete one task. Henry Ford and others have written about the influence of this slaughterhouse practice on the later developments at Ford Motor Company.\n20th century.\nAccording to Domm, the implementation of mass production of an automobile via an assembly line may be credited to Ransom Olds, who used it to build the first mass-produced automobile, the Oldsmobile Curved Dash. Olds patented the assembly line concept, which he put to work in his Olds Motor Vehicle Company factory in 1901.\nAt Ford Motor Company, the assembly line was introduced by William \"Pa\" Klann upon his return from visiting Swift & Company's slaughterhouse in Chicago and viewing what was referred to as the \"disassembly line\", where carcasses were butchered as they moved along a conveyor. The efficiency of one person removing the same piece over and over without himself moving caught his attention. He reported the idea to Peter E. Martin, soon to be head of Ford production, who was doubtful at the time but encouraged him to proceed. Others at Ford have claimed to have put the idea forth to Henry Ford, but Pa Klann's slaughterhouse revelation is well documented in the archives at the Henry Ford Museum and elsewhere, making him an important contributor to the modern automated assembly line concept. Ford was appreciative, having visited the highly automated 40-acre Sears mail order handling facility around 1906. At Ford, the process was an evolution by trial and error of a team consisting primarily of Peter E. Martin, the factory superintendent; Charles E. Sorensen, Martin's assistant; Clarence W. Avery; C. Harold Wills, draftsman and toolmaker; Charles Ebender; and József Galamb. Some of the groundwork for such development had recently been laid by the intelligent layout of machine tool placement that Walter Flanders had been doing at Ford up to 1908.\nThe moving assembly line was developed for the Ford Model T and began operation on October 7, 1913, at the Highland Park Ford Plant, and continued to evolve after that, using time and motion study. The assembly line, driven by conveyor belts, reduced production time for a Model T to just 93 minutes by dividing the process into 45 steps. Producing cars quicker than paint of the day could dry, it had an immense influence on the world.\nIn 1922, Ford (through his ghostwriter Crowther) said of his 1913 assembly line:\nCharles E. Sorensen, in his 1956 memoir \"My Forty Years with Ford\", presented a different version of development that was not so much about individual \"inventors\" as a gradual, logical development of industrial engineering:\nAs a result of these developments in method, Ford's cars came off the line in three-minute intervals or six feet per minute. This was much faster than previous methods, increasing production by eight to one (requiring 12.5 man-hours before, 1 hour 33 minutes after), while using less manpower. It was so successful, paint became a bottleneck. Only japan black would dry fast enough, forcing the company to drop the variety of colours available before 1914, until fast-drying Duco lacquer was developed in 1926.\nThe assembly line technique was an integral part of the diffusion of the automobile into American society. Decreased costs of production allowed the cost of the Model T to fall within the budget of the American middle class. In 1908, the price of a Model T was around $825, and by 1912 it had decreased to around $575. This price reduction is comparable to a reduction from $15,000 to $10,000 in dollar terms from the year 2000. In 1914, an assembly line worker could buy a Model T with four months' pay.\nFord's complex safety procedures—especially assigning each worker to a specific location instead of allowing them to roam about—dramatically reduced the rate of injury. The combination of high wages and high efficiency is called \"Fordism\", and was copied by most major industries. The efficiency gains from the assembly line also coincided with the take-off of the United States. The assembly line forced workers to work at a certain pace with very repetitive motions which led to more output per worker while other countries were using less productive methods.\nIn the automotive industry, its success was dominating, and quickly spread worldwide. Ford France and Ford Britain in 1911, Ford Denmark 1923, Ford Germany and Ford Japan 1925; in 1919, Vulcan (Southport, Lancashire) was the first native European manufacturer to adopt it. Soon, companies had to have assembly lines, or risk going broke by not being able to compete; by 1930, 250 companies which did not had disappeared.\nThe massive demand for military hardware in World War II prompted assembly-line techniques in shipbuilding and aircraft production. Thousands of Liberty ships were built making extensive use of prefabrication, enabling ship assembly to be completed in weeks or even days. After having produced fewer than 3,000 planes for the United States Military in 1939, American aircraft manufacturers built over 300,000 planes in World War II. Vultee pioneered the use of the powered assembly line for aircraft manufacturing. Other companies quickly followed. As William S. Knudsen (having worked at Ford, GM and the National Defense Advisory Commission) observed, \"We won because we smothered the enemy in an avalanche of production, the like of which he had never seen, nor dreamed possible.\"\nImproved working conditions.\nIn his 1922 autobiography, Henry Ford mentions several benefits of the assembly line including:\nThe gains in productivity allowed Ford to increase worker pay from $1.50 per day to $5.00 per day once employees reached three years of service on the assembly line. Ford continued on to reduce the hourly work week while continuously lowering the Model T price. These goals appear altruistic; however, it has been argued that they were implemented by Ford in order to reduce high employee turnover: when the assembly line was introduced in 1913, it was discovered that \"every time the company wanted to add 100 men to its factory personnel, it was necessary to hire 963\" in order to counteract the natural distaste the assembly line seems to have inspired.\nSociological problems.\nSociological work has explored the social alienation and boredom that many workers feel because of the repetition of doing the same specialized task all day long.\nOne of capitalism's most famous critics, Karl Marx, expressed in his \"Entfremdung\" theory the belief that, in order to achieve job satisfaction, workers need to see themselves in the objects they have created, that products should be \"mirrors in which workers see their reflected essential nature\". Marx viewed labour as a chance for people to externalize facets of their personalities. Marxists argue that performing repetitive, specialized tasks causes a feeling of disconnection between what a worker does all day, who they really are, and what they would ideally be able to contribute to society. Furthermore, Marx views these specialised jobs as insecure, since the worker is expendable as soon as costs rise and technology can replace more expensive human labour.\nSince workers have to stand in the same place for hours and repeat the same motion hundreds of times per day, repetitive stress injuries are a possible pathology of occupational safety. Industrial noise also proved dangerous. When it was not too high, workers were often prohibited from talking. Charles Piaget, a skilled worker at the LIP factory, recalled that besides being prohibited from speaking, the semi-skilled workers had only 25 centimeters in which to move. Industrial ergonomics later tried to minimize physical trauma.", "Engineering,_Manufacturing": 0.9999145269, "qwen": "Yes"}
{"id": "44987397", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=44987397", "title": "Adamant Co., Ltd.", "text": " is a component manufacturing company based in Tokyo, Japan. Its name is from the word \"adamant\", which was derived from the Greek word \"adamas\" meaning \"diamond\". At of its founding, Adamant's main products were watch jewels that were made of a hard material.\nIn 1957, Adamant separated from Namiki Precision Jewel Co., Ltd. It started sales of jewel bearings for watches and clocks and began to manufacture cap jewel, hole jewel, impulse jewel and pallet stone. In 1980, it started manufacturing ferrules for the optical communication industry utilizing injection molding engineering and polishing techniques.\nAdamant merged with its parent company, Namiki Precision Jewel Co., Ltd., to establish Adamant Namiki Precision Jewel Co., Ltd. on January 1, 2018.\nProducts.\nPhotonics.\nZirconia ferrule, sleeve, receptacle and connector incorporating Injection molding techniques.\nLensed fiber, lens is formed on top of optical fiber which is equivalent with human hair.\nMEMS (Micro Electro Mechanical System).\nStarted full foundry service covering development →test production　→and OEM Manufacturing of MEMS in tie-ups with Micralyne Inc. in Canada.\nPursuant to joint development with Micralyne Inc. for optical sensor device incorporating MEMS.VOA（Variable Optical Attenuator）and optical switch with hermetically sealed in metal package\nFine industrial jewel.\nCapillaries for bonding tool, wedge, also, ruby knife, pellet, dental block for medical device, physics and chemistry.\nAdvanced material.\nVariety of color Ceramics available such as White, Black, Blue and Brown.\nFeaturing glossy by polishing finish and a high-class touch. \nLTCC（Low Temperature Co-fired Ceramics）\nare co-fired at low temperature (900°C) in process which makes silver material possible in order to use as a conductor.\nSuited for RF products due to low loss. Also, multi-layered and flat substrate can be made easily. Highly accurate, high-density mounting are realized.", "Engineering,_Manufacturing": 0.9970750213, "qwen": "Yes"}
{"id": "2507742", "revid": "1135513110", "url": "https://en.wikipedia.org/wiki?curid=2507742", "title": "KPackage", "text": "KPackage was KDE's package manager frontend.\nIt supported BSD, Debian, Gentoo, RPM and Slackware packages. It provided a GUI for the management and upgrade of existing packages and the installation and acquirement of new packages. Additionally, it provided functionality to help manage package caches. KPackage was part of kdeadmin, and was developed at KDE.org.", "Engineering,_Manufacturing": 1.0000050068, "qwen": "Yes"}
{"id": "23155455", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=23155455", "title": "Laser cutting bridge", "text": "In textile manufacturing, a laser cutting bridge system is an industrial machine for cutting and engraving textile materials (i.e. fabrics). It is formed by a galvanometric laser head and carbon-dioxide laser ( laser) source that runs along an horizontal beam (the bridge) supported by two lateral columns and sometimes by central columns. This system is placed over one or more embroidery machines, more frequently multi-head rather than single-head machines, cutting tables and roller devices to cut out and/or engrave embroidered fabrics.\nHistory.\nThe first laser bridge for embroidery machines was invented and realized in 1998 by GMI srl an Italian company based in Vittorio Veneto (TV), Italy. The Laser cutting bridge was first presented to the public at the IMB exhibition of Cologne, Germany in 2000. GMI srl continues manufacturing laser bridges and since 1998 has largely improved the quality of its cutting systems.\nBefore the advent of the laser bridge, fabrics were first die-cut and then appliqués were sewed or embroidered on the base fabric. Usually used as an 8 mm thick steel die with heights ranging from 50 to 100 mm depending on how many pieces were to be cut at once. This process proved to present numerous difficulties.\nTechnology.\nA cut piece of cloth (the appliqué) is placed above the base material that is in the embroidery machine (having a first seam reference), is fixed and finally embroidered. More recently, the manual method of cutting has been replaced by the laser cutting technology, laser plotters first, and then by laser bridges. The laser ensures better accuracy compared to manual cutting. It allows users to imitate a jagged or irregular cut as if done by hand, with the advantage that the laser solders the borders of synthetic fiber, avoiding unpleasant unthreading which is called \"the clean edge\". The combination \"laser plus embroidery machine\" offered by the laser bridge also avoids double work: no longer is it necessary to cut by hand after embroidering appliqués.\nThe process also guarantees more accurate results, because the laser works on the same frame where the embroidery machine works avoiding positioning errors. The technology uses software that guides the cutting laser head along the bridge and the reflecting mirrors (moved by electromagnetic motors). This method provides a degree of accuracy and speed of cut much greater than traditional systems (1/100 mm instead of 1/10 mm).", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "59888778", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=59888778", "title": "NCSIMUL", "text": "NCSIMUL is a software program developed by the company SPRING Technologies, that is used for simulating, verifying, and optimizing CNC machining in a 3-step process. It reads the post-processed G-code to identify the tool path, and replicates the material removal process of the machine by cutting volumes. It then identifies all syntax errors in the code, crashes in the machining environment, and deviations from the modeled CAD part.\nHistory.\nNCSIMUL's development began in 1983, and currently has 140 partners world-wide, and over 2000 licenses of NCSIMUL in use. It was founded in Paris, France, but has since expanded to China, Germany, the United States, India, Mexico, and Spain. The US headquarters was founded in 2009, and is located in Boston, Massachusetts. In August 2018 it was acquired by the global technology group Hexagon AB. NCSIMUL is current members of the AMT and National Center for Defense Manufacturing and Machining (NCDMM).\nFeatures.\nNCSIMUL Machine.\nNCSIMUL Machine is designed for turning, drilling, milling (up to 5-axis), mill-turn, and multi-channel machines. Based on the real characteristics of the CNC machine, it creates a dynamic verification software that includes the exact environment for all machines, tools and materials.\nNCSIMUL 4CAM.\nWith the release of V10, NCSIMUL added the capability to change the target machine without CAM reprogramming. It is able to perform the necessary recalculations across different number of axes and across different controller languages. NCSIMUL generates verified and optimized CNC programs directly, without an external post-processor, while taking into account the real machining environment.\nNCSIMUL Optitool.\nNCSIMUL can optimize the tool length, air-cutting motions, and cutting conditions by regulating feed rates to create better G-code programs in 3 to 5-axis machining. These strategies result in a reduction for the production cycle times, enhancement of cutting operations, and fast development of new G-code optimized files for future applications.\nNCSIMUL Interfaces.\nAdditionally, NCSIMUL integrates directly with several CAM systems to transfer all previously created resources including tool libraries, fixturing, part models, and G-code directly into the machining verification software.", "Engineering,_Manufacturing": 0.9999241829, "qwen": "Yes"}
{"id": "56305886", "revid": "13756482", "url": "https://en.wikipedia.org/wiki?curid=56305886", "title": "Hot gas welding", "text": "Hot-gas welding is a manual plastic welding process for joining thermoplastic materials. A hot-gas torch is used to direct hot air to both the joint surface and weld rod, heating the materials to their softening temperature. Application of pressure on the heated weld rod to the joint surface bonds the materials together to form a completed weld. This technique is not easily automatized and is primarily used for repairs or individual manufacturing needs of small or complex components.\nWelding techniques.\nThere are two common forms of welding techniques used in hot gas welding: hand welding and speed welding. Tack welding may be utilized to set the components in position to perform the actual welding process.\nHand welding.\nHand welding is a technique in which the weld rod is applied to the joint by the welder directly. This is also referenced as \"free-hand welding\" or \"fan welding\". The hot gas torch is maneuvered in one hand to heat both the weld rod and joint surfaces in a pendulum manner in quick succession. Pressure is applied to the welding rod and controlled by hand without the assistance of a nozzle. This technique is suitable for most configurations and can be beneficial for welding tight, constrained areas or complex joint designs since application of the welding rod is only limited to the achievable welding positions.\nSpeed welding.\nSpeed welding employs a specially designed nozzle which enables the hot gas torch and weld rod to be one cohesive system. The nozzle facilitates application of the weld rod to the joint through a feeder tube. The nozzle evenly heats the weld rod material and allows for a controlled application of pressure. The bottom of the nozzle is designed to heat the joint surface and guide the weld rod into the groove. Nozzles are manufactured for the feeder tubes to accommodate specific welding rod shapes and dimensions and are available for round or triangular rods of common sizes. Use of speed welding is limited to applications of simple joint design and orientation due to the size of the nozzle and maneuverability of the system.\nProcess parameters.\nGas temperature, application pressure, weld travel speed, gas flow rate, and torch orientation all influence the integrity and mechanical properties of the finished weld. Gas temperature and flow rate are controllable parameters based on system inputs. Application pressure, weld travel speed, and torch orientation are all dependent upon the operator performing the weld. These parameters are interrelated and all have a significant impact on the final quality of the weld.\nGas temperature and flow rate.\nGas temperature is a controlled input that should be monitored for accuracy prior to initiating the welding process. Hot gas temperatures are selected at values above the material's melting or glass transition temperature. Sufficient temperature is required to overcome a materials activation energy, resulting in a reduction of the viscosity and an increase in flowability to support diffusion across the weld interface. Prolonged exposure to elevated temperatures exceeding material manufacturer's recommendations can result in oxidation, distortion, or molecular deterioration, which can lead to joint failure. Calibration and verification of the output should be performed after the gas temperature has stabilized in the welding gun. Speed tip nozzles focus heat directly on the joint in a specific region, resulting in effective heat transfer to the weld surfaces. If sufficient weld travel speed is not maintained, recommended welding temperatures above the glass or melting temperature of the material in these weld regions can be exceeded and lead to defects.\nThermal expansion from the welding process may result in distortion and development of weld defects if part components are not properly secured. Work surface material should also be considered to avoid heat losses which may result in lack of penetration or lack of fusion due to inadequate heating of the joint surfaces.\nSufficient hot gas flow rate is necessary to maintain adequate, even heating of weld rod and joint surfaces. Flow rate can be controlled through the use of a blower or an air compressor. To avoid weld contamination, supplied hot gas should be free of moisture and should not contain impurities. A properly sized blower or compressor can be utilized for multiple hot gas torches if one is not integrated in the individual welding gun.\nWelding energy.\nThe welding energy imparted on the weld surface during hot gas welding can be used to predict the overall strength of the finished joint. Welding energy (\"Ew\") is determined using the gas temperature and flow rate using the following relationship:\nformula_1\nwhere hot gas parameters include the specific heat (\"cp\"), initial and final temperature (\"T1\" and \"T2\", respectively), volumetric flow rate (\"qv\"), and density (formula_2). These properties are divided by the weld travel speed (\"Sw\"). Studies performed on semi-crystalline materials conclude the higher the welding energy input on the surface, the higher the joint strength. A high welding energy has been related to a lower welding surface viscosity. A less viscous surface allows for increased diffusion across the weld interface resulting in a stronger weld, whereas a higher viscosity does not support diffusion as easily and can result in lower joint strength.\nHot gas properties vary depending on the type of medium used for welding. Air is used in most applications. In certain instances, the material manufacturer may recommend use of other types of hot gas such as carbon dioxide or nitrogen when a potential health and safety risk may be present under other welding conditions.\nPressure.\nApplication pressure impacts the overall weld penetration and joint quality. Pressure is manually applied either through the weld rod directly or to the speed tip nozzle. Welding technique and joint design both influence the amount of pressure that is translated to the weld.\nInadequate pressure can result in weld interface porosity, poor wettability, and lack of fusion defects. Hot gas can become trapped between the weld rod and joint surface resulting in pore formation. One way to reduce the presence of pores is to establish a root gap as part of the joint design through which hot gases can escape. Unfused regions of the weld and presence of pores can significantly reduce the overall strength of the joint.\nPressure application can be less effective in hand welding compared to utilizing a speed tip; however both are dependent upon the skill of the operator. Double-V joint designs are well-suited for carrying higher effective welding pressure as compared to single-V joints and are less prone to fusion deficiencies.\nWeld travel speed.\nMaterial properties of the components being welded, hot gas temperature, size of the weld rod, and technique utilized all influence the weld travel speed. Due to the manual nature of hot gas welding, this process is typically slower than other thermoplastic welding methods. Higher weld travel speed can be obtained using a speed tip. Localization of high temperature gas on the weld surface allows for thermoplastics to heat up faster and flow easier, resulting in an increase in capable welding speed. Too fast of a welding speed can stretch the weld rod, unevenly filling the joint and compromising the overall weld strength. If the speed is too slow, weld damage from extended high temperature exposure can result.\nTorch orientation.\nThe angle of orientation of the welding torch and welding rod is dependent upon the welding technique, rod material, and joint design.\nSpeed welding.\nTo establish consistent pressure while maintaining proper alignment to the joint groove during speed tip welding, it is recommended that the welder position their grip below the hot gas gun. Sufficient penetration and weld quality is achieved when the weld rod is slightly pressured as it is fed through the feeder tube and a simultaneous downward pulling motion is maintained at a constant travel speed throughout the welding pass.\nHand welding.\nOrientation of the welding rod to the groove is material dependent in hand welding applications. Recommended weld rod angles are established for materials based on achieving proper penetration without introducing flaws or additional stresses in the joint. Accurate positioning will result in a visible “\"bow wave\"” effect at the root, indicating diffusion across the weld interface occurred. Improper angle can result in uneven heating and weld defects or insufficient pressure to produce a strong joint.\nWelder qualifications.\nIn industrial applications, hot gas welding processes are successfully executed by trained and qualified operators who have been certified in the process as detailed in EN 13067 or AWS B2.4. EN 13067 is the International standard for qualification of welders for thermoplastic welded assemblies, which includes hot gas welding techniques and processes. The American Welding Society (AWS) published AWS B2.4 as an American standard for qualification for thermoplastic welding procedures and performance. These standards detail proper technique and joint design to be employed for various welding situations. ", "Engineering,_Manufacturing": 1.000005722, "qwen": "Yes"}
{"id": "56329781", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=56329781", "title": "Adamant Namiki Precision Jewel Co", "text": "Adamant Namiki Precision Jewel Co., Ltd. ( アダマンド並木精密宝石 Adamant Namiki Seimitsu Houseki Kabushiki-gaisha) is a Japanese precision components manufacturer based in Tokyo, Japan.\nOverview.\nIn 1939, Namiki Precision Jewel Co., Ltd. started business as a manufacturer of synthetic sapphire jewel bearings for electrical measuring instruments. It later began selling these jewel bearings for use in watches in the 1960s. In 1957, Adamant Shoji (renamed Adamant Kogyo Co., Ltd. in 1959, and Adamant Co., Ltd. in 2014) was founded as a spin-off of Namiki as a result of business practices of the time. Thereafter, Namiki developed its product lineup primarily focusing on industrial jewel components, DC coreless motors, and medical devices. Meanwhile, Adamant Shoji’s business focused mainly on optical communication components. In 2017, Namiki and Adamant mutually agreed to unite their specialties to take their technologies and products to the next level. As a result, Adamant Namiki Precision Jewel Co., Ltd. was established on January 1, 2018.\nHistory.\nSee Namiki Precision Jewel Co., Ltd. and Adamant Co., Ltd. for the history of each company prior to the January 1, 2018 intragroup merger.\nNamiki merged with its subsidiary company, Adamant Co., Ltd., on January 1, 2018 and changed its name to Adamant Namiki Precision Jewel Co., Ltd.\nPrimary business.\nIndustrial jewel components.\nAdamant Namiki uses integrated manufacturing, handling its products from the raw material, to processing, through to polishing. Industrial jewels, such as diamond, sapphire, and ruby, are used for jewel bearings, sapphire substrates, exterior watch parts, semiconductor wire bonding capillaries, nozzles, LTCC(Co-fired ceramic) and so on.\nFor sapphire product growth, Adamant Namiki employs the highly productive EFG method. \nIn 2021, the company succeeded in developing a mass production method for 2-inch diamond wafers.\nAdamant Namiki also supplies ceramic parts, combining precision processing and various molding technologies, such as injection, powder press, and CIP molding, to provide a diverse range of products.\nOptical components.\nAdamant Namiki offers optical components with a focus on ferrules, sleeves, and connectors. \nA ferrule is a component to link optical fibers together and high-precision (less than 1 micrometer) processing technology is required to ensure the secure connection of several micrometer optical fiber cores. \nAdamant Namiki also combines its high-precision processing and assembly technologies to provide optical device components such as receptacles and pigtails, optical switches using MEMS(Microelectromechanical systems) technology, and optical devices such as variable attenuators.\nDC coreless motors.\nSince developing the smallest coreless motor of the time in 1973, Adamant Namiki has been consistently producing miniature DC coreless motors. The core components have evolved with high-precision processing technology and a more optimal magnetic circuit has produced a high-efficiency motor. In 2009, Adamant Namiki successfully developed the world’s smallest DC brushless motor at 0.6mm in diameter. The company also produces motor units such as its de-energized locking system, micro robot servo, multi-finger robotic hand, and micro mechanisms.\nMedical devices.\nSince the start of OEM manufacturing of its computer-controlled infusion pump in 1987, Adamant Namiki has established a line of business that offers medical device development, manufacturing, and service.", "Engineering,_Manufacturing": 0.9999238253, "qwen": "Yes"}
{"id": "56343748", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=56343748", "title": "Laser welding of polymers", "text": "Laser welding of polymers is a set of methods used to join polymeric components through the use of a laser. It can be performed using CO2 lasers, Diode lasers and Fiber lasers. \nWhen a laser encounters the surface of plastics, it can be reflected, absorbed or penetrate through the thickness of a component. Laser welding of plastics is based on the energy absorption of laser radiation, which can be reinforced by additives and fillers. \nLaser welding techniques include:\nBecause of high joining speeds, low residual stresses and excellent weld appearances, laser welding processes have been widely used for automotive and medical applications.\nLaser sources.\nThe types of lasers used in the welding of polymers include CO2 lasers, Nd:YAG lasers, Diode lasers and fiber lasers. CO2 lasers are mostly applied to weld thin films and thin plastics due to the high energy absorption coefficients of most plastics. Nd:YAG lasers and Diode lasers produce short wavelength radiation, which transmit through several millimeters of unpigmented polymer. They are used in the transmission laser welding techniques.\nCarbon dioxide lasers.\nCarbon dioxide lasers have a wavelength of 10.6 μm which is rapidly absorbed by most polymers. Because of the high-energy absorption coefficients, processing of plastics using CO2 can be done rapidly with low laser powers. This type of laser can be used in direct welding of polymers or cutting. However, the penetration of CO2 lasers is less than 0.5 mm and is mostly applicable for the welding of thin film and surface heating. Because the beam cannot be transmitted by silicon fiber, the beam is commonly delivered by mirrors.\nNd:YAG lasers.\nNd:YAG lasers have a wavelength in the range of 0.8 - 1.1 μm, with 1064 nm being the most common. These lasers provide a high beam quality allowing for small spot sizes. This type of beam can be delivered via fiber optic cable.\nDiode lasers.\nThe wavelength of diode lasers is typically in the 780 - 980 nm wavelength range. Compared with Nd:YAG laser and CO2 laser, diode laser has supreme advantage in energy efficiency. The high-energy light wave can penetrate a thickness of a few millimeters in semicrystalline plastics and further in unpigmented amorphous plastics. Diode lasers can be either fiber delivered or local to the weld location. The relatively small size makes assembling arrays for larger foot prints possible.\nFiber laser.\nFiber lasers typically exhibit wavelengths ranging from 1000 to 3500 nm. The expanded range of wavelengths has allowed for the development of through transmission welding without additional absorbing additives.\nEquipment.\nThe equipment settings may vary greatly in design and complexity. However, there are five components included in most of the machines: \nGenerator/Power supply.\nThis component transforms the received voltage and frequency to the corresponding voltage, current and frequency to the laser source. Diode laser and fiber laser are the two most commonly used system for laser welding.\nControl interface.\nThe control interface is an interface between operator and machine to monitor operations of the system. It is constructed by logic circuits to send operators the information of machine status and welding parameters. Depending on different laser modes, the control interface will vary the parameters allowable to change.\nActuator.\nThis component is a press activated by pneumatical and electrical power. It compresses the part in the upper fixture to touch the components in the lower fixture and apply pre-determined loads during welding processes. Displacement controls are added to actuators to monitor precisely the movements.\nLower fixture.\nLower fixture is a jig structure that locates the lower part of a joint. It provides locations and alignments that ensure the welding of components with tight tolerances.\nUpper fixture.\nThe upper fixture is the most complicated and important component in the whole system. Laser beam is generated in this component to heat up the welding parts. The design of upper fixture often varies from laser sources and heating modes. For example, when a YAG laser or a diode laser is used as the heat source, optical fibers are often employed to provide mobility. However, the welding part cannot move.\nLaser interaction with polymers.\nThere are three types of interactions that can occur between laser radiation and plastics: \nThe extent of individual interaction is dependent upon materials properties, laser wavelength, laser intensity and beam speed.\nReflection.\nReflection of incident laser radiation is typically on the order of 5 to 10% in most polymers, which is low compared with absorption and transmission. The fraction of reflection (R) can be determined by the following equation,\nformula_1\nwhere formula_2 is the index of refraction of the plastics and formula_3 is the index of refraction of air (~1).\nTransmission.\nTransmission of laser energy through certain polymers allows for processes such as through transmission welding. When the laser beam travel through the interfaces between different medium, the laser beam is refracted unless the path is perpendicular to the surface. This effect needs to be considered when laser travels through multi-layer to reach the joint region.\nInternal scattering occur when laser pass through the thickness in semicrystalline plastics, where crystalline and amorphous phase have different index of refraction. Scattering can also occur in crystalline and amorphous plastics with reinforcement like glass fiber and certain colorants and additives. In transmission laser welding, such effect can reduce the effective energy of laser radiation towards joint area and limit the thickness of components.\nAbsorption.\nLaser absorption can occur at the surface of plastics or during transmission through thickness. The amount of laser energy absorbed by a polymer is a function of the laser wavelength, polymer absorptivity, polymer crystallinity, and additives (i.e. composite reinforcements, pigments, etc.). The absorption at surface has two possible ways, photolytic and pyrolytic. \nThe heat distribution within a laser welded polymer is dictated by the Bouger–Lambert law of absorption.\n\"I(z) = I(z=0) eKz\"\nwhere I(z) is the laser intensity at a certain depth z, I(z=0) is the laser intensity at the surface, K is the absorption constant.\nEffect of additives.\nPolymers often have secondary elements added to them for various reasons (i.e. strength, color, absorption, etc.). These elements can have a profound effect on the laser interaction with the polymer component. Some common additives and their effect on laser welding are described below.\nReinforcements.\nVarious fibers are added to polymeric materials to create higher strength composites. Some typical fiber materials include: glass, carbon fiber, wood, etc. When the laser beam interacts with these materials it can get scattered or absorbed, changing the optical properties from that of the base polymer. In laser transmission welding, a transparent material with reinforcement may absorb or dilute the energy beam more, effecting the quality of the weld. High contents of glass fiber content increase the scattering within the plastics and raise the laser energy input for welding a certain thickness.\nColorants.\nColorants (pigments) are added to polymers for various reasons including aesthetics and functional requirements (such as optics). Certain color additives, such as titanium dioxide, can have a negative impact on the laser weldability of a polymer. The titanium dioxide provides a white coloring to polymers but also scatters laser energy making it difficult to weld. Another color additive, carbon black, is a very effective energy absorber and is often added to create welds. By controlling the concentration of carbon black with the absorbing polymer it is possible to control the effective area of the laser weld.\nLaser application configurations.\nThe laser beam energy can be delivered to the required areas through a variety of configurations. The four most common approaches include: \nContour heating.\nIn the contour heating (laser scanning or laser moving) technique, a laser beam of fixed dimension passes through the desired area to create a continuous weld seam. The laser source is manipulated by a galvanic mirror or a robotic system to scan at a fast rate. The benefit of contour heating is that the weld can be performed with a single laser source, which can be reprogramed for different applications; however, due to the localized heating area, uneven contact between welding components can occur and form weld voids. The important parameters for this technique include: laser wavelength, laser power, traverse speed, and polymer properties.\nSimultaneous heating.\nIn the simultaneous heating approach, a beam spot of appropriate size is used to irradiate the entire weld area without the need for relative movement between the work piece and the laser source. For creating a weld with a large area, multiple laser sources can be combined to melt the selected region simultaneously. This approach can be adopted to substitute ultrasonic welding in the case of welding components sensitive to vibration. Key processing parameters for this approach include: laser wavelength, laser power, heating time, clamp pressure, cooling time, and polymer properties.\nQuasi-simultaneous heating (QSLW).\nIn the quasi-simultaneous heating, a work area is irradiated by the use of scanning mirrors. The mirrors raster the laser beam over the entire work area rapidly, creating a simultaneously melted region. Some of the important parameters for this technique include: laser wavelength, laser power, heating time, cooling time, polymer properties.\nMasked heating.\nMasked heating is a process of laser line scanning through a region with a mask, which ensures that only the selected areas can be heated when the laser pass through. Masks can be made out of laser cut steel, or other materials that effectively block the laser radiation. This approach is capable of creating micro-scale welds on components with complex geometries. Key processing parameters for this approach include: laser wavelength, laser power, heating time, clamp pressure, cooling time, and polymer properties.\nLaser welding techniques.\nDepending on different interactions between laser and thermoplastics, four different laser welding techniques have been developed for plastic joining. CO2 lasers have good surface absorption for most thermoplastics, hence they are applied for direct laser welding and laser surface heating. Through transmission laser welding and intermediate film welding require the deep penetration of laser beam, so YAG lasers and diode lasers are the most common sources for these techniques.\nDirect laser welding.\nSimilar to laser welding of metals, in direct laser welding the surface of the polymer is heated to create a melt zone that joins two components together. This approach can be used to create butt joints and lap joints with complete penetration. Laser wavelengths between 2 and 10.6μm are used for this process due to their high absorptivity in polymers.\nLaser surface heating.\nLaser surface heating is similar to non-contact hot plate welding in that mirrors are placed between components to create a molten surface layer. The exposure duration is usually between 2-10 s. Then the mirror is retracted and the components are pressed together to form a joint. Process parameters for laser surface heating include the laser output, wavelength, heating time, change-over time, and forging pressure and time.\nThrough transmission laser welding (TTLW).\nThrough transmission laser welding of polymers is a method to create a joint at the interface between two polymer components with different transparencies to laser wavelengths. The upper component is transparent to the laser wavelength between 0.8 µm to 1.05 µm, and the lower component is either opaque in nature, or modified by the addition of colorants which promote the absorption of laser radiation. A typical colorant is carbon black that absorb most of the electromagnetic wavelength. When the joint is irradiated by the laser, the transparent layer passes the light with minimal loss while the opaque layer absorbs the laser energy and heats up.\nThe two components are held by the lower fixture to control alignment and a small clamping force is added to the upper part to form intimate contact. A melt layer is then created at the interface between the two components, composed of a mixture of two plastic materials.\nThere are four different modes of transmission laser welding: scanning mode, simultaneous, quasi-simultaneous, and mask heating.\nMany benefits can be obtained by transmission laser welding such as fast welding velocity, flexibility, good cosmetic properties and low residual stresses. From processing perspectives, laser welding can be performed in the pre-assembled conditions, reducing the necessity for complex fixtures; however, this method is not suitable for plastics with high crystallinity due to refraction and geometric limitations.\nIntermediate film welding.\nIntermediate film welding is a method to join incompatible plastic components by using an intermediate film between them. Similar to transmission welding, laser radiation passes through the transparent components and melts the intermediate layers to create a joint. This film can be made of an opaque thermoplastic, solvent, viscous fluid, or other substances that heat up upon exposure to laser energy. The combination of intermediate films and adhesion promoters is able to join incompatible thermoplastics together. The thin layer then generates the heat required to fuse the system together.\nApplications.\nAutomotive applications.\nThe black body of car keys is welded by the Through Transmission Laser Welding (TTLW) technique, in which laser radiation transmits through the upper component and forms a joint at the interface. Carbon black is added to the lower part of car keys to absorb laser radiation. The black color of the upper part is made by the addition of dye, which makes the component appear black but transparent to laser radiation.\nOther applications of laser welding in automotive industry include brake fluid reservoirs and lighting components.\nMedical applications.\nLaser welding of plastics is applied to weld medical devices like IV-bags. Joints of high geometrical complexity can be produced by laser welding without particulate formation. This is critical for the safety of patients, when welding techniques are applied to produce IV-bags containing blood. In addition, flashes generated during welding can cause blood turbulences and destroy blood platelets. A good control of the laser power avoids flash formation and thus protects the blood cells from damage.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "26602975", "revid": "12120664", "url": "https://en.wikipedia.org/wiki?curid=26602975", "title": "Package testing", "text": "Package testing or packaging testing involves the measurement of a characteristic or property involved with packaging. This includes packaging materials, packaging components, primary packages, shipping containers, and unit loads, as well as the associated processes.\nTesting measures the effects and interactions of the levels of packaging, the package contents, external forces, and end-use.\nIt can involve controlled laboratory experiments, subjective evaluations by people, or field testing. Documentation is important: formal test method, test report, photographs, video, etc.\nTesting can be a qualitative or quantitative procedure. Package testing is often a physical test. With some types of packaging such as food and pharmaceuticals, chemical tests are conducted to determine suitability of food contact materials. Testing programs range from simple tests with little replication to more thorough experimental designs.\nPackage testing can extend for the full life cycle. Packages can be tested for their ability to be recycled and their ability to degrade as surface litter, in a sealed landfill or under composting conditions.\nPurposes.\nPackaging testing might have a variety of purposes, such as:\nPackaging tests can be used for:\nImportance of testing.\nFor some types of products, package testing is mandated by regulations: food. pharmaceuticals, medical devices, dangerous goods, etc. This may cover both the design qualification, periodic retesting, and control of the packaging processes. Processes may be controlled by a variety of quality management systems such as HACCP, statistical process control, validation protocols, ISO 9000, etc.\nFor unregulated products, testing can be required by a contract or governing specification. The degree of package testing can often be a business decision. Risk management may involve factors such as\nWith distribution packaging, one vital packaging development consideration is to determine if a packaged-product is likely to be damaged in the process of getting to the final customer. A primary purpose of a package is to ensure the safety of a product during transportation and storage. If a product is damaged during this process, then the package has failed to accomplish a primary objective and the customer will either return the product or be unlikely to purchase the product altogether.\nPackage testing is often a formal part of Project management programs. Packages are usually tested when there is a new packaging design, a revision to a current design, a change in packaging material, and various other reasons. Testing a new packaging design before full scale manufacturing can save time and money.\nLaboratory affiliation.\nMany suppliers or vendors offer limited material and package testing as a free service to customers. It is common for packagers to partner with reputable suppliers: Many suppliers have certified quality management systems such as ISO 9000 or allow customers to conduct technical and quality audits. Data from testing is commonly shared. There is sometimes a risk that supplier testing may tend to be self-serving and not completely impartial.\nLarge companies often have their own packaging staff and a package testing and development laboratory. Corporate engineers know their products, manufacturing capabilities, logistics system, and their customers best. Cost reduction of existing products and cost avoidance for new products have been documented.\nAnother option is to use a paid consultant, Independent contractor, and third-party independent testing laboratory. They are commonly chosen for specialized expertise, for access to certain test equipment, for surge projects, or where independent testing is otherwise required. Many have certifications and accreditations: ISO 9000, ISO/IEC 17025, and various governing agencies.\nProcedures.\nSeveral standards organizations publish test methods for package testing. Included are:\nGovernments and regulators publish some packaging test methods. There are also many corporate test standards in use. A review of technical literature and patents provides good options to consider for test procedures.\nResearchers are not restricted to the use of published standards but can modify existing test methods or develop procedures specific to their particular needs. If a test is conducted with a deviation from a published test method or if a new method is employed, the test report must fully disclose the procedure.\nMaterials testing.\nThe basis of packaging design and performance is the component materials. The physical properties, and sometimes chemical properties, of the materials need to be communicated to packaging engineers to aid in the design process. Suppliers publish data sheets and other technical communications that include the typical or average relevant physical properties and the test method these are based upon. Sometimes these are adequate. Other times, additional material and component testing is required by the packager or supplier to better define certain characteristics.\nWhen a final package design is complete, the specifications for the component materials needs to be communicated to suppliers. Packaging materials testing is often needed to identify the critical material characteristics and engineering tolerances. These are used to prepare and enforce specifications.\nFor example, shrink film data might include: tensile strength (MD and CD), elongation, Elastic modulus, surface energy, thickness, Moisture vapor transmission rate, Oxygen transmission rate, heat seal strength, heat sealing conditions, heat shrinking conditions, etc. Average and process capability are often provided. The chemical properties related for use as Food contact materials may be necessary.\nTesting with people.\nSome types of package testing do not use scientific instruments but use people for the evaluation.\nThe regulations for child-resistant packaging require a test protocol that involves children. Samples of the test packages are given to a prescribed population of children. With specified 50-child panels, a high percentage must be unable to open a test package within 5 minutes.\nAdults are also tested for their ability to open a child-resistant package.\nConsumer packages are often evaluated by focus groups. People evaluate the package features in a room monitored by video cameras. The consumer responses are treated qualitatively for feedback into the new packaging process.\nSome food packagers use organoleptic evaluations. People use their senses (taste, smell, etc.) to determine if a package component has tainted the food in the package.\nA new package may be evaluated in a test market that uses people to try the packages at home. Consumers have the opportunity to buy a product, perhaps with a coupon or discount. Return postcards or Internet sites provide feedback to package developers. Perhaps the most critical feedback is repeated sales items in the new package. Packaging evaluations are an important part of marketing research.\nLegibility of text on packaging and labels is always subjective due to the inherent variations of people. Efforts have been made to help better quantify this by people in a laboratory: still using people for the evaluation but also employing a test apparatus to help reduce variability.\nSome laboratory tests are conducted but still result in an observation by people. Some test procedures call for a judgment by test engineers whether or not pre-established acceptance criteria have been met.\nConditioning, testing atmosphere.\nThe environmental conditions of testing are critical. The measured performance of many packages is affected by the conditioning and testing atmospheres. For example, paper based products are strongly affected by their moisture content: Relative humidity needs to be controlled. Plastic products are often strongly affected by temperature.\nConditions of 23 °C (73.4 °F) and 50% relative humidity are common but other standard testing conditions are also published in material and package test standards. Engineering tolerances for the conditions are also specified. Often the package is conditioned to the specified environment and tested under those conditions. This can be in a conditioned room or in a chamber enclosing the test. With some testing, the package is conditioned to a specified environment, then is removed to ambient conditions and quickly tested. The test report needs to state the actual conditions used.\nEngineers have found it important to know the effects of the full range of expected conditions on package performance. This can be through investigating published technical literature, obtaining supplier documentation, or by conducting controlled tests at diverse conditions.\nDegradation of product.\nLaboratory tests can help determine the shelf life of a package and its contents under a variety of conditions. This is particularly important for foods, pharmaceuticals, some chemicals, and a variety of products. The testing is usually product specific: the mechanisms of degradation are often different. Exposures to expected and elevated temperatures and humidities are commonly used for shelf life testing. The ability of packaging to control product degradation is frequently a subject of laboratory and field evaluations.\nBarrier Properties.\nMany products degrade with exposure to the atmosphere: foods, pharmaceuticals, chemicals, etc. The ability of a package to control the permeation and penetration of gasses is vital for many types of products. Tests are often conducted on the packaging materials but also on the completed packages, sometimes after being subjected to flexing, handling, vibration, or temperature.\nDegradation of Packages.\nPackages can degrade with exposure to temperature, humidity, time, sterilization (steam, radiation, gas, etc.), sunlight, and other environmental factors. For some types of packaging, it is common to test for possible corrosion of metals, polymer degradation, and weather testing of polymers. Several types of accelerated aging of packaging and materials can be accomplished in a laboratory.\nExposure to elevated temperatures accelerates some degradation mechanisms. An Arrhenius equation is often used to correlate certain chemical reactions at different temperatures, based on the proper choice of Q10 coefficients.\nConsiderations to ambient levels of humidity was introduced in ASTM F1980-21, Section 6.0, to account for packaging materials that have hydrolytic degradation risk.\nAs with any laboratory testing, validating field trials are important.\nVacuum testing.\nVacuum chambers are used to test the ability of a package to withstand low pressures. This can be to:\nShock and impact.\nBoth primary (consumer) packages and shipping containers have a risk of being dropped or being impacted by other items. Package integrity and product protection are important packaging functions. Tests are conducted to measure the resistance of packages and products to controlled laboratory shock and impact.\nTesting also determines the effectiveness of package cushioning to isolate fragile products from shock. Instrumentation is used to measure the shock transmitted to a cushioned product. Simple drop test can be used with the tube-style shock sensor with different threshold of shock and impact. One or more sensors were attached to the primary package during each drop test, oriented such that the sensitive axes of the sensors were aligned to the drop axis.\nPackage Insulation.\nMany packages are used for products that are sensitive to temperature. The ability of insulated shipping containers to protect their contents from exposure to temperature fluctuations can be measured in a laboratory. The testing can be of empty containers or of full containers with appropriate jell or ice packs, contents, etc. Ovens, freezers, and environmental chambers are commonly used for this and other types of packaging.\nDigital temperature data loggers are used to measure temperatures experienced in different distribution systems. This data is sometimes used to develop unique laboratory test methods for that distribution system.\nThermal shock.\nSome packages, particularly glass, can be sensitive to sudden changes in temperature: Thermal shock. One method of testing involves rapid movement from cold to hot water baths, and back.\nHandles.\nPackage handles (and hand holes in packages) assist carrying and handling packages. Objective laboratory procedures are frequently used to help determine performance. Fixtured ‘’hands’’ of various designs are used to hold a handle (sometimes two handles for a box). Most common are “jerk testing’’ by modified drop test procedures or use of the constant pull rates of a universal testing machine. Other procedures use a static force by hanging a heavily loaded package for an extended time or even using a centrifuge.\nVibration.\nVibration is encountered during shipping (vehicle vibration, rough roads, etc.) and movement on conveyors. Potential vibration damage may include:\nThe ability of a package to withstand these vibrations and to protect the contents can be measured by several laboratory test procedures. Some allow searching for the particular frequencies of vibration that have potential for damage. Modal testing methodologies are sometimes employed. Others use specified bands of random vibration to better represent complex vibrations measured in field studies of distribution environments.\nCompression.\nCompression testing relates to stacking or crushing of packages, particularly shipping containers. It usually measures of the force required to crush a package, stack of packages, or a unit load. Packages can be empty or filled as for shipment. A force-deflection curve used to obtain the peak load or other desired points. Other tests use a constant load and measure the time to failure or to a critical deflection.\nDynamic compression is sometimes tested by shock or impact testing with an additional load to crush the test package. Dynamic compression also takes place in stacked vibration testing.\nLarge loads.\nLarge pallet loads, bulk boxes, wooden boxes, and crates can be evaluated by many of the other test procedures previously listed. In addition, some special test methods are available for these larger loads.\nBar codes.\nPackage bar codes are evaluated for several aspects of legibility by bar code verifiers as part of a continuing quality program. More thorough validation may include evaluations after use (and abuse) testing such as sunlight, abrasion, impact, moisture, etc.\nTest Protocols for Shipping Containers.\nShipping containers are often subjected to sequential tests involving a combination of individual test methods. A variety of standard test schedules or protocols are available for evaluating transport packaging. They are used to help determine the ability of complete and filled shipping containers to various types of logistics systems. Some test the general ruggedness of the shipping container while others have been shown to reproduce the types of damage encountered in distribution. Some base the type and severity of testing on formal studies of the distribution environment: instrumentation, data loggers, and observation. Test cycles with these documented elements better simulate parts of certain logistics shipping environments.\nProduct requirements.\nIn addition, package testing often relates to the specific product inside the package. Some broad categories of products and special package testing considerations follow:\nFood packaging.\nFoods categories such as fresh produce, frozen foods, irradiated foods, fresh fish, canned foods, etc. have regulatory requirements and special packaging needs. Package testing often relates to:\nPharmaceutical packaging.\nPackaging for drugs and pharmaceuticals is highly regulated. Special testing needs include:\nMedical Packaging.\nPackaging for medical materials, medical devices, health care supplies, etc., have special user requirements and is highly regulated. Barrier properties, durability, visibility, sterility and strength need to be controlled; usually with documented test results for initial designs and for production.\nAssurance of sterility and suitability for use are critical. For example, medical devices and products are often sterilized in the package. The sterility must be maintained throughout distribution to allow immediate use by physicians. A series of special packaging tests is used to measure the ability of the package to maintain sterility. Verification and validation protocols are rigidly maintained.\nDangerous Goods.\nPackaging of hazardous materials, or dangerous goods, are highly regulated. There are some material and construction requirements but also performance testing is required. The testing is based on the packing group (hazard level) of the contents, the quantity of material, and the type of container.\nResearch into improvements is continuing.", "Engineering,_Manufacturing": 0.9999787807, "qwen": "Yes"}
{"id": "7518831", "revid": "2300502", "url": "https://en.wikipedia.org/wiki?curid=7518831", "title": "Draft (engineering)", "text": "In engineering, draft is the amount of taper for molded or cast parts perpendicular to the parting line. It can be measured in degrees or mm/mm (in/in).\nConsider the fabrication of a hollow plastic box, without lid. Once the plastic has hardened around the mold, the mold must be removed. As the plastic hardens, it may contract slightly. By tapering the sides of the mold by an appropriate \"draft angle\", for instance 2° (two degrees), the mold will be easier to remove. This is a practice that is used, in applicable cases, when working with fiberglass.\nIf the mold is to be removed from the top, the box should taper in towards the bottom, such that measuring the bottom internal dimension will yield a smaller length and width than measuring the top from which the mold is extracted.\nBy specifying the opening length and width, a draft angle, and a depth, it is not necessary to specify the dimensions for the internal surface, as these may be calculated from the above.\nThe manufacture of a part that incorporates zero or negative angles may require a mold that can be separated into two or more parts, in order to release the casting.", "Engineering,_Manufacturing": 0.9998674393, "qwen": "Yes"}
{"id": "5102157", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=5102157", "title": "Device under test", "text": "A device under test (DUT), also known as equipment under test (EUT) and unit under test (UUT), is a manufactured product undergoing testing, either at first manufacture or later during its life cycle as part of ongoing functional testing and calibration checks. This can include a test after repair to establish that the product is performing in accordance with the original product specification.\nElectronics testing.\nIn the electronics industry a DUT is any electronic assembly under test. For example, cell phones coming off of an assembly line may be given a final test in the same way as the individual chips were earlier tested. Each cell phone under test is, briefly, the DUT.\nFor circuit boards, the DUT is often connected to the test equipment using a bed of nails tester of pogo pins.\nSemiconductor testing.\nIn semiconductor testing, the device under test is a die on a wafer or the resulting packaged part. A connection system is used, connecting the part to automatic or manual test equipment. The test equipment then applies power to the part, supplies stimulus signals, then measures and evaluates the resulting outputs from the device. In this way, the tester determines whether the particular device under test meets the device specifications.\nWhile packaged as a wafer, automatic test equipment (ATE) can connect to the individual units using a set of microscopic needles. Once the chips are sawn apart and packaged, test equipment can connect to the chips using ZIF sockets (sometimes called \"contactors\").", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "5110256", "revid": "398607", "url": "https://en.wikipedia.org/wiki?curid=5110256", "title": "Bio Process Systems Alliance", "text": "The Bio Process Systems Alliance (BPSA) is a biopharmaceutical industry trade group of suppliers of single use components and single use systems for manufacturing processes. It was created in 2006 through an alliance of 26 suppliers.", "Engineering,_Manufacturing": 0.9999682903, "qwen": "Yes"}
{"id": "40560282", "revid": "9710872", "url": "https://en.wikipedia.org/wiki?curid=40560282", "title": "High Precision", "text": "High Precision Inc. is an American industrial manufacturing company based in Hamden, Connecticut. It was founded in 1945 by Ermon F. Ayer as a flexible contract manufacturer, and is currently under third generation family ownership and management. The company originally built pipe organs, later branching out into aerospace components, heavy-duty industrial pneumatic tools, torque limiters, and custom CNC machining.\nCurrently, High Precision Inc. mainly serves the petroleum and chemical refining, plant maintenance, and medical component manufacturing industries.\nThe company currently occupies a 40,000 square foot manufacturing facility in Hamden, CT.", "Engineering,_Manufacturing": 1.0000013113, "qwen": "Yes"}
{"id": "13462088", "revid": "44873595", "url": "https://en.wikipedia.org/wiki?curid=13462088", "title": "Mickey J. Meyer", "text": "Mickey J. Meyer is an Indian music composer and singer known for his works predominantly in Telugu Cinema. He has received two Filmfare Awards South, and three state Nandi Awards for the Best Music Direction. An alumnus of Trinity College of Music, Meyer started his career in 2005 and composed music for films such as \"Happy Days\" (2007), \"Kotha Bangaru Lokam\" (2008), Leader (2010) and \"A Aa\" (2016).\nAwards.\n2007: Best Music Director – \"Happy Days\"\n2008: Best Music Director – \"Kotha Bangaru Lokam\"\n2016: Best Music Director – \"A Aa\"\n2007: Best Music Director – Telugu – \"Happy Days\"\n2008: Best Music Director – Telugu – \"Kotha Bangaru Lokam\"\n2018: Best Music Director – Telugu – Mahanati ", "Engineering,_Manufacturing": 0.999129951, "qwen": "Yes"}
{"id": "13466269", "revid": "39497554", "url": "https://en.wikipedia.org/wiki?curid=13466269", "title": "Specific identification (inventories)", "text": "Specific identification is a method of finding out ending inventory cost. \nIt requires a detailed physical count, so that the company knows exactly how many of each good bought on specific dates comprise the year-end inventory. When this information is found, the amount of goods are multiplied by their purchase cost at their purchase date, to get a number for the ending inventory cost. \nIn theory, this method is the best method, since it relates the ending inventory goods directly to the specific price they were bought for. However, this method allows management to easily manipulate ending inventory cost, since they can choose to report that the cheaper goods were sold first, hence increasing ending inventory cost and lowering cost of goods sold. This will increase the income. Alternatively, management can choose to report lower income, to reduce the taxes they needed to pay. \nThis method is also very hard to use on interchangeable goods. For example, it is hard to relate shipping and storage costs to a specific inventory item. These numbers will need to be estimated, hence reducing the specific identification method's benefit of being extremely specific. Thus, this method is generally limited to large, high-ticket items which can be easily identified specifically (such as tract houses).", "Engineering,_Manufacturing": 0.9979060888, "qwen": "Yes"}
{"id": "17900572", "revid": "1154322480", "url": "https://en.wikipedia.org/wiki?curid=17900572", "title": "Overall equipment effectiveness", "text": "Overall equipment effectiveness (OEE) is a measure of how well a manufacturing operation is utilized (facilities, time and material) compared to its full potential, during the periods when it is scheduled to run. It identifies the percentage of manufacturing time that is truly productive. An OEE of 100% means that only good parts are produced (100% \"quality\"), at the maximum speed (100% \"performance\"), and without interruption (100% \"availability\").\nMeasuring OEE is a manufacturing best practice. By measuring OEE and the underlying losses, important insights can be gained on how to systematically improve the manufacturing process. OEE is an effective metric for identifying losses, bench-marking progress, and improving the productivity of manufacturing equipment (i.e., eliminating waste). The best way for reliable OEE monitoring is to automatically collect all data directly from the machines.\nTotal effective equipment performance (TEEP) is a closely related measure which quantifies OEE against calendar hours rather than only against scheduled operating hours. A TEEP of 100% means that the operations have run with an OEE of 100% 24 hours a day and 365 days a year (100% \"loading\").\nThe term OEE was coined by Seiichi Nakajima. It is based on the Harrington Emerson way of thinking regarding labor efficiency. The generic form of OEE allows comparison between manufacturing units in differing industries. It is not however an absolute measure and is best used to identify scope for process performance improvement, and how to get the improvement.\nOEE measurement is also commonly used as a key performance indicator (KPI) in conjunction with lean manufacturing efforts to provide an indicator of success. OEE can be illustrated by a brief discussion of the six metrics that comprise the system (the \"Six Big Losses\").\nCalculations for OEE and TEEP.\nThe OEE of a manufacturing unit are calculated as the product of three separate components:\nTo calculate the TEEP, the OEE is multiplied by a fourth component:\nThe calculations of OEE are not particularly complicated, but care must be taken as to standards that are used as the basis. Additionally, these calculations are valid at the work center or part number level but become more complicated if rolling down to aggregate levels.\n9 Majors Downtime Losses Affect Availability\nOverall equipment effectiveness.\nEach of the three components of the OEE points to an aspect of the process that can be targeted for improvement. OEE may be applied to any individual Work Center, or rolled up to Department or Plant levels. This tool also allows for drilling down for very specific analysis, such as a particular Part Number, Shift, or any of several other parameters.\nIt is unlikely that any manufacturing process can run at 100% OEE. Many manufacturers benchmark their industry to set a challenging target; 85% is not uncommon.\nAlternatively, and often easier, OEE is calculated by dividing the minimum time needed to produce the parts under optimal conditions by the actual time needed to produce the parts. For example:\nTotal effective equipment performance.\nWhereas OEE measures efficiency based on scheduled hours, TEEP measures efficiency against calendar hours, i.e.: 24 hours per day, 365 days per year.\nTEEP, therefore, reports the 'bottom line' utilization of assets.\nTEEP = Loading * OEE\nLoading.\nThe Loading portion of the TEEP Metric represents the percentage of time that an operation is scheduled to operate compared to the total Calendar Time that is available. The Loading Metric is a pure measurement of Schedule efficiency and is designed to exclude the effects how well that operation may perform.\nCalculation: Loading = Scheduled Time / Calendar Time\n\"Example:\"\nA given Work Center is scheduled to run 5 Days per Week, 24 Hours per Day.\nFor a given week, the Total Calendar Time is 7 Days at 24 Hours.\nLoading = (5 days x 24 hours) / (7 days x 24 hours) = 71.4%\nAvailability.\nThe Availability portion of the OEE Metric represents the percentage of scheduled time that the operation is available to operate. The Availability Metric is a pure measurement of Uptime that is designed to exclude the effects of Quality and Performance. The losses due to wasted availability are called \"availability losses\".\n\"Example:\"\nA given Work Center is scheduled to run for an 8-hour (480-minute) shift with a 30-minute scheduled break and during the break the lines stop, and unscheduled downtime is 60 minutes.\nThe scheduled time = 480 minutes - 30 minutes = 450 minutes.\nOperating Time = 480 Minutes – 30 Minutes Schedule Loss – 60 Minutes Unscheduled Downtime = 390 Minutes\nCalculation: Availability = operating time / scheduled time\nAvailability = 390 minutes / 450 minutes = 86.6%\nPerformance and productivity.\nAlso known as \"process rate\", the Performance portion of the OEE Metric represents the speed at which the Work Center runs as a percentage of its designed speed. The Performance Metric is a pure measurement of speed that is designed to exclude the effects of Quality and Availability. The losses due to wasted performance are also often called \"speed losses\". In practice it is often difficult to determine speed losses, and a common approach is to merely assign the remaining unknown losses as speed losses.\nCalculation: Performance (Productivity) = (Parts Produced * Ideal Cycle Time) / Operating time\n\"Example:\"\nA given Work Center is scheduled to run for an 8-hour (480-minute) shift with a 30-minute scheduled break.\nOperating Time = 450 Min Scheduled – 60 Min Unscheduled Downtime = 390 Minutes\nThe Standard Rate for the part being produced is 40 Units/Hour or 1.5 Minutes/Unit\nThe Work Center produces 242 Total Units during the shift. Note: The basis is Total Units, not Good Units. The Performance metric does not penalize for Quality.\nTime to Produce Parts = 242 Units * 1.5 Minutes/Unit = 363 Minutes\nPerformance (Productivity) = 363 Minutes / 390 Minutes = 93.1%\nQuality.\nThe Quality portion of the OEE Metric represents the Good Units produced as a percentage of the Total Units Started. The Quality Metric is a pure measurement of Process Yield that is designed to exclude the effects of Availability and Performance. The losses due to defects and rework are called \"quality losses\" and \"quality stops\".\nReworked units which have been corrected are only measured as \"unscheduled downtime\" while units being scrapped can affect both operation time and unit count.\nCalculation: Quality = (Units produced - defective units) / (Units produced)\n\"Example:\"\n242 Units are produced. 21 are defective.\n(242 units produced - 21 defective units) = 221 units\n221 good units / 242 total units produced = 91.32%\n\"Six Big Losses\".\nTo be able to better determine the sources of the greatest loss and to target the areas that should be improved to increase performances, these categories (Availability, Performance and Quality) have been subdivided further into what is known as the 'Six Big Losses' to OEE.\nThese are categorized as follows:\nThe reason for identifying the losses in these categories is so that specific countermeasures can be applied to reduce the loss and improve the overall OEE.\nTotal Productive Maintenance.\nContinuous improvement in OEE is the goal of TPM (Total Productive Maintenance). Specifically, the goal of TPM as set out by Seiichi Nakajima is \"The continuous improvement of OEE by engaging all those that impact on it in small group activities\". To achieve this, the TPM toolbox sets out a Focused improvement tactic to reduce each of the six types of OEE loss. For example, the Focused improvement tactic to systematically reduce breakdown risk sets out how to improve asset condition and standardise working methods to reduce human error and accelerated wear.\nCombining OEE with Focused improvement converts OEE from a lagging to a leading indicator. The first Focused improvement stage of OEE improvement is to achieve a stable OEE. One which varies at around 5% from the mean for a representative production sample. Once an asset efficiency is stable and not impacted by variability in equipment wear rates and working methods. The second stage of OEE improvement (optimisation) can be carried out to remove chronic losses. Combining OEE and TPM Focused improvement tactics creates a leading indicator that can be used to guide performance management priorities. As the TPM process delivers these gains through small cross functional improvement teams, the process of OEE improvement raises front line team engagement/problem ownership, collaboration and skill levels. It is this combination of OEE as a KPI, TPM Focused improvement tactics and front line team engagement that locks in the gains and delivers the TPM goal of year on year improvement in OEE.\nHeuristic.\nOEE is useful as a heuristic, but can break down in several circumstances. For example, it may be far more costly to\nrun a facility at certain times. Performance and quality may not be independent of each other or of availability and loading.\nExperience may develop over time. Since the performance of shop floor managers is at least sometimes compared to the OEE, these numbers are often not reliable, and there are numerous ways to fudge these numbers.\nOEE has properties of a geometric mean. As such it punishes variability among its subcomponents. For example, 20% * 80% = 16%,\nwhereas 50% * 50% = 25%. When there are asymmetric costs associated with one or more of the components, then the model may become less appropriate.\nConsider a system where the cost of error is exceptionally high. In such a condition, higher quality may be far more important\nin a proper evaluation of efficiency than performance or availability. OEE also to some extent assumes a closed system and a potentially static one. If one can bring in additional resources (or lease out unused resources to other projects or business units) then it may be more appropriate for example to use an expected net present value analysis.\nVariability in flow can also introduce important costs and risks that may merit further modeling. Sensitivity analysis and measures of change may be helpful.", "Engineering,_Manufacturing": 1.0000059605, "qwen": "Yes"}
{"id": "4219180", "revid": "21112944", "url": "https://en.wikipedia.org/wiki?curid=4219180", "title": "Ball in and out of play", "text": "The ball in and out of play is the ninth law of the Laws of the Game of association football, and describes to the two basic states of play in the game.\nIn play.\nThe ball remains \"in play\" from the beginning of each period to the end of that period, except when:\nThe first criterion can be phrased as \"\"all\" of the ball must cross \"all\" of the line\" and is of particular importance in decisions regarding goals. The question of whether the ball has crossed the line has often caused controversy in high-profile matches, such as in the example of Geoff Hurst's goal in the 1966 World Cup Final, that put England 3-2 up over West Germany in extra time. The Law specifically notes that the ball remains in play if it rebounds off a goal frame or corner flag onto the field, or in any case of the ball touching a match official that is not mentioned above. \nWhen the ball is in play players may play the ball, contest the ball, and goals may be scored. Players are liable to punishment for committing fouls. Substitutions may not occur whilst the ball is in play.\nIn the case a foul is committed or misconduct occurs, the referee may \"play advantage\" and elect to allow play to continue if the team of the player who was victimized would be benefited if play were to continue. Once play has stopped, the referee may choose to issue punishments.\nRestarts.\nWhen the ball becomes out of play, the ball is put back into play by the appropriate restart. The restarts in football are:\nOnce the ball is out of play, the only restart is the restart appropriate for the reason the ball went out of play in the first place; subsequent actions do not change the restart. For example, if the ball goes out of play because of a foul by Team A against Team B, the restart must be a free kick to Team B even if a Team B player strikes an opponent; offending Team B player would, however, be liable for misconduct (i.e. yellow card or red card).\nNote, however, that the referee may change the \"original\" restart if he realises he has made an error or on the advice of his assistant referees, provided play has not yet restarted. For example, if the ball has gone out of play because the ball was kicked into goal by Team A and the referee has signalled that a goal has been scored, but then notices that an assistant referee has indicated a foul by a Team A player immediately before the goal was scored, the referee would change to the correct restart of a free kick to Team B where the foul occurred.", "Engineering,_Manufacturing": 0.9944091439, "qwen": "Yes"}
{"id": "19290581", "revid": "829949", "url": "https://en.wikipedia.org/wiki?curid=19290581", "title": "Order processing", "text": "Order processing is the process or work-flow associated with the picking, packing, and delivery of the packed items to a shipping carrier and is a key element of order fulfillment. Order processing operations or facilities are commonly called “distribution centers” or “DC 's”. There are wide variances in the level of automation associating to the “pick-pack-and-ship” process, ranging from completely manual and paper-driven to highly automated and completely mechanized; computer systems overseeing this process are generally referred to as Warehouse Management Systems or “WMS”.\nProcess.\nOrder processing is a sequential process involving:\nPicking.\nOrder picking or order preparation is one of a logistic warehouse's processes.\nIt consists in taking and collecting articles in a specified quantity before shipment to fulfil customer orders.\nIt is a basic warehousing process and has an important influence on logistic processes.\nIt is one of the warehouse management system functions.\nPicking Strategies.\nThere are several strategies for order picking, including:\nNote that these strategies are not mutually exclusive to each other. For example, wave picking can be used to batch picks, which are then handled via zone or piece picking. A warehouse may also need to support alternate picking strategies due to physical layout or product distribution; for example, if some products are only sold by pallet and require special lifting equipment, those pallet-orders might be batched or processed differently that the rest of the products which might be piece-picked — alternatively, part of a warehouse might be automated with sorting systems while another part is not.\nPiece Picking.\nPiece picking, also known as broken case picking or pick/pack operations, describes systems where individual items are picked. Operations using piece picking typically have a large stock keeping unit, or SKU, base in the thousands or tens of thousands of items, small quantities per pick, and short cycle times. Examples of piece pick operations include mail-order catalog companies and repair parts distributors.\nCase Picking.\nOperations that use case picking tend to have less diversity in product characteristics than operations that use piece picking. There are typically fewer SKUs and higher picks per SKU.\nPallet Picking.\nFull-pallet picking, or unit-load picking, uses much simpler systematic methods than piece picking or case picking. However, there are many choices in storage equipment, storage configurations and types of lift trucks.\nSorting.\nSorting machines in distribution\nPick and pack.\nPick and pack is a part of a complete supply chain management process that is commonly used in the retail distribution of goods. It entails processing small to large quantities of product, often truck or train loads and disassembling them, picking the relevant product for each destination and re-packaging with shipping label affixed and invoice included. Usual service includes obtaining a fair rate of shipping from common, as well as expediting truck carriers.\nPick and Pack services are offered by many businesses that specialize in supply chain management solutions.\nCase picking is the gathering of full cartons or boxes of product. This is often done on a pallet. In the consumer products industry, case picking large quantities of cartons is frequently an entry-level employee's task. There is, however, significant skill required to make a good pallet load of product. Key requirements are that cartons not be damaged, they make good use of the available cube (space) and be quick to assemble.\nWarehouse management system products create pick paths to minimize the travel distance of an order selector, but typically neglect the need to maximize the use of cube, segregate products that should not touch or minimize damage.\nFactors.\nThe specific \"order fulfillment process\" or the operational procedures of distribution centers are determined by many factors. Each distribution center has its own unique requirements or priorities. There is no \"one size fits all\" process that universally provides the most efficient operation. Some of the factors that determine the specific process flow of a distribution center are:\nThis list is only a small sample of factors that can influence the choice of a distribution center's operational procedures. Because each factor has varying importance in each organization, the net effect is that each organization has unique processing requirements.\nThe effect of Globalization has immense impacts on much of the order fulfillment, but its impact is felt mostly in transportation and distribution.", "Engineering,_Manufacturing": 0.9999055862, "qwen": "Yes"}
{"id": "19298923", "revid": "17252052", "url": "https://en.wikipedia.org/wiki?curid=19298923", "title": "Soldering station", "text": "A soldering station is a multipurpose power soldering device designed for electronic components soldering. This type of equipment is mostly used in electronics and electrical engineering. Soldering station consists of one or more soldering tools connected to the main unit, which includes the controls (temperature adjustment), means of indication, and may be equipped with an electric transformer. Soldering stations may include some accessories – holders and stands, soldering tip cleaners, etc. \nSoldering stations are widely used in electronics repair workshops, electronic laboratories, in industry. Sometimes simple soldering stations are used for household applications and for hobbies. \nSoldering Station Components.\nThe main soldering station elements which determine its compatibilities are soldering tools. Different tools are used for different applications and soldering stations may be equipped with more than one of them at a time. The main tools for soldering are:\nSoldering iron is the most common working tool of a soldering station. Some stations may use simultaneously several soldering irons to make the process quicker and more convenient, as there is no need to change the soldering tips or readjust the station or the soldering temperature. Some stations may use some specialized soldering irons, such as ultrasonic soldering irons or induction soldering irons. \nSoldering Irons.\nSoldering iron as a part of soldering station has a number of advantages. \nIncreased user comfort.\nHowever, most soldering stations can only be used on your desktop. Also, it costs more than just a separate soldering iron.\nDesoldering Tools.\nDesoldering is a very important stage in PCB repair. It is often needed to disassemble some components just to make sure they work or check their condition. That is why it is important to detach the elements without any possible damage to them. \nThe means that may be integrated in soldering stations are:\nSMD hot tweezers heat up and may not only melt the solder alloy but grab the needed component as well. They may have different types of tips for different applications. \nDesoldering iron is usually made in a shape of a gun. It is capable of taking in the air (vacuum pickup) and solder alloy. \nNon-contact heating tools include hot air and infrared heaters. They are used for SMT disassembling. \nHot Air Guns.\nThey use a hot air stream for heating up the components. Hot air is focused on the certain area using special hot air nozzles. Usually soldering hot air guns are capable of providing temperatures from 100 to 480 °C.\nInfrared Heaters.\nSoldering stations with infrared (IR) heaters are a separate type of soldering stations and differ a lot. Such stations provide high-precision soldering and the process is more like that in electronics industry. The temperature profile may be set based on the components being soldered. This minimizes the risk of components deformation or damage due to the temperature difference.\nSoldering Station Classification.\nContact Soldering Stations.\nThis type requires a soldering iron equipped with an electronic temperature adjustment unit. The main technical parameter of the contact soldering station is the power. The power determines the operation convenience and soldering effectiveness. The modern stations have power from 10 to 200 W and more. The most common are the models with 50-80 W power. The higher is the power the more amount of heat you may transmit for the same time. It allows reducing the temperature on the heating element to the minimal possible value for melting the solder alloy. And vice versa – the lower is the power the higher temperature you need to melt the solder. High temperature means a risk of a component overheating. Especially it concerns semiconductor components or electrolytic conductors.\nAccording to the solder alloy used these soldering stations may be divided into two subtypes:\nLead-free soldering stations.\nThis type of stations is characterized by heating element with a power up to 160 W. Lead-free solder alloys need higher temperatures to be melted, so the station needs more power. If the station is equipped with a temperature regulator, it may be used for operation with a traditional lead-containing solder.\nDigital and analogue soldering stations.\nThe stations may be divided into digital and analogue according to the control unit operation method. \nAnalogue stations have a temperature stabilization that operates as follows:\nThe operation is ensured by the magnetoelectric relay. It is controlled by electronics and a temperature sensor. Analogue control system has an advantage – it is the cost. The disadvantage is a low operation precision that results in soldering tip overheating. This leads to problems like: electronic components overheating, often tip change. \nDigital soldering station is operating using a PID regulator that is controlled by a microprocessor. Digital control method is more precise. \nInduction soldering stations.\nInduction soldering stations are characterized by high power and excellent thermal stability. They use the technology of heating and thermal stabilization based on Curie temperature. \nAmerican manufacturer Metcal is a leader in this market segment, however there are other brands. \nNon-contact soldering stations.\nHot air soldering stations.\nStations with hot air guns are used in cases when just a soldering iron is not enough. Disassembling microchips requires a hot air gun. SMD components soldering with hot air is much more convenient. Hot air guns usually come with special nozzles for hot air stream regulation. \nPopular manufacturers: Hakko, Quick, Accta, Goot, etc.\nRework systems.\nFor professional laptop, game console and other electronics repair, special repair systems are used. These repair systems usually combine several components: hot air gun, soldering iron, desoldering gun, etc. This equipment allows effective desoldering and soldering large BGAs. These operations require special approach and certain amount of process automation. \nThe most popular manufacturers: Ersa, Martin, Jovy Systems, Quick, Scotle.", "Engineering,_Manufacturing": 0.9999973774, "qwen": "Yes"}
{"id": "5876914", "revid": "12109628", "url": "https://en.wikipedia.org/wiki?curid=5876914", "title": "Aeroxchange", "text": "Aeroxchange is a neutral purchasing portal for the aviation industry based in Irving, Texas. Founded in July 2000 and commenced operations a couple of months later on October 1, 2000. It is the only electronic business network that supports all MRO business processes within the aviation industry for buyer and sellers. Aeroxchange provides a complete lifecycle of electronic communication from order creation to final invoice. The Aeroxchange service accelerates repair, replenishment, sourcing, inventory pooling and other critical operations in the aviation supply chain. Aeroxchange automates the exchange of documents and information for commercial transactions. Its electronic platform dramatically reduces manual activity for transaction processed by fax, telephone and email, and increases the accuracy and timeliness of information and document exchange.\nFounded by 13 airlines, Aeroxchange has been joined by 20 other airlines and several suppliers. The founders include Air Canada, Air New Zealand, All Nippon Airways, America West Airlines, Austrian Airlines Group, Cathay Pacific Airways, FedEx Express, Japan Airlines, KLM, Lufthansa, Northwest Airlines, Scandinavian Airlines System and Singapore Airlines.\nThe service focuses on the repair, replenishment, sourcing, consignment/VMI, inventory pooling and other critical operations in the aviation supply chain. It automates the exchange of documents and information for commercial transactions. Aeroxchange claims, “Our electronic platform dramatically reduces manual activity for transaction processed by fax, telephone and email, and increases the accuracy and timeliness of information and document exchange.” ", "Engineering,_Manufacturing": 0.9950057268, "qwen": "Yes"}
{"id": "5880752", "revid": "38769897", "url": "https://en.wikipedia.org/wiki?curid=5880752", "title": "Almen strip", "text": "An Almen strip is a thin strip of SAE 1070 steel used to quantify the intensity of a shot peening process.\nDeveloped and patented by John O. Almen, the strip was originally supported by 2 knife edges; later improvements see it being supported on 4 small balls. The strip is placed in the chamber in place of the item to be shot peened, usually near to an area of the item where the result is deemed critical, sometimes located by a special fixture. Compressive stress introduced by the peening operation causes the strip to deform into an arch, which is measured using a gauge.\nAlmen strips are classified into 3 types: 'A', 'N', and 'C'. They differ in their thickness, while they have the same width and length. \nAlthough similar, the specification for Almen strip dimensions of the same type slightly vary from one company/organization to another. The Almen strips are made from plain carbon steel SAE 1070 and have hardness about 45 HRC. \nThis test is widely used and the requirements for check are specified in standards. \nThe most rigid requirements are applicable for Almen strips and checking devices (Almen gauges) used in the aerospace industry. The generic requirements can be found in SAE specifications.\nAnother operation to gauge the intensity of a shot peening process is the use of an Almen round, developed by R. Bosshard.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "64528168", "revid": "12970725", "url": "https://en.wikipedia.org/wiki?curid=64528168", "title": "Electroless copper plating", "text": "Electroless copper plating is a chemical process that deposits an even layer of copper on the surface of a solid substrate, like metal or plastic. The process involves dipping the substrate in a water solution containing copper salts and a reducing agent such as formaldehyde.\nUnlike electroplating, electroless plating processes in general do not require passing an electric current through the bath and the substrate; the reduction of the metal cations in solution to metallic is achieved by purely chemical means, through an autocatalytic reaction. Thus electroless plating creates an even layer of metal regardless of the geometry of the surface – in contrast to electroplating which suffers from uneven current density due to the effect of substrate shape on the electric field at its surface. Moreover, electroless plating can be applied to non-conductive surfaces.\nProcess.\nIn a typical formulation of the process, the surfaces to be coated are primed with a palladium catalyst and then immersed in a bath containing copper ions , which are reduced by formaldehyde through the overall reactions\nApplications.\nElectroless copper plating is used in the manufacture of printed circuit boards (PCBs), in particular for the conductive layer on the walls of through holes and vias.", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "15305798", "revid": "1098221593", "url": "https://en.wikipedia.org/wiki?curid=15305798", "title": "Silver mica capacitor", "text": "Silver mica capacitors are high precision, stable and reliable capacitors. They are available in small values, and are mostly used at high frequencies and in cases where low losses (high Q) and low capacitor change over time is desired.\nHistory.\nMica has been used as a capacitor dielectric since the mid-19th century. William Dubilier invented a small mica capacitor in 1909 which was used in decoupling applications. They were put into large scale commercial production to meet military requirements in World War I. Mica is less prone to crack under mechanical shock than glass, a useful property for equipment subject to shellfire. Like glass, mica has a substantially higher permittivity than paper so capacitors can be made smaller. In 1920 Dubilier developed a capacitor consisting of a flaked sheet of mica coated on both sides with silver. He formed the Dubilier Condenser Company to manufacture them. Ceramic capacitors were also used in the 1920s due to a shortage of mica, but by the 1950s silver mica had become the capacitor of choice for small-value RF applications. This remained the case until the latter part of the 20th century when advances in ceramic capacitors led to the replacement of mica with ceramic in most applications.\nTypes.\nThere are 2 distinct types of mica capacitor.\nClamped mica capacitors.\nNow obsolete, these were in use in the early 20th century. They consisted of sheets of mica and copper foil sandwiched together and clamped. These had even worse tolerance and stability than other clamped capacitors since the mica surface is not perfectly flat and smooth. References to mica capacitors from the 1920s often refer to this type.\nSilver mica capacitors.\nCommonly known as silver mica capacitors, these rendered clamped mica capacitors obsolete. Instead of being clamped with foils these are assembled from sheets of mica coated on both sides with deposited metal. The assembly is dipped in epoxy. The advantages are:\nThey are sometimes informally referred to as mica capacitors. Any modern reference to mica capacitors can be assumed to mean these, unless pre-World War II equipment is being discussed. Even though these capacitors are extremely useful, silver mica capacitors are less commonly used today due to bulkiness and high cost. There is a high level of compositional variation in the raw material leading to higher costs in relation to inspection and sorting. They are getting closer to obsolescence as advances are made in ceramic and porcelain materials.\nSilver mica capacitors are still indispensable in some custom applications. Circuit designers still turn to mica capacitors for high-power applications such as RF transmitters and electric instruments and amplifiers because cheaper ceramic and porcelain capacitors can't withstand heat as well. Silver mica remains widely used in high-voltage applications, due to mica’s high breakdown voltage. Silver Mica capacitors are used at 100 V to 10 kV, ranging from a few pF up to a few nF, and the average temperature coefficient is around 50 ppm/°C.", "Engineering,_Manufacturing": 0.999751389, "qwen": "Yes"}
{"id": "30870002", "revid": "5984052", "url": "https://en.wikipedia.org/wiki?curid=30870002", "title": "New manufacturing economy", "text": "The new manufacturing economy (NME) describes the role of advanced manufacturing in the rise of the New Economy. The term describes manufacturing enabled by digital technologies, advanced systems and processes and a highly trained and knowledgeable workforce. The new manufacturing economy integrates networks, 3D printers and other proficiencies into business strategies to further develop manufacturing practices.\nThomas Friedman references Lawrence F. Katz that hubs of \"universities, high-tech manufacturers, software/service providers and highly nimble start-ups\" are a needed economic development strategy. This is very similar to NME thoughts even though that exact term is not used.\nThe Pillars of the new manufacturing economy.\nTechnology.\nFocus on geographic expansion, information technology and internet commerce are on the rise for industrial manufacturing companies according to the PricewaterhouseCoopers Q4 2010 Manufacturing Barometer. Such conditions compel companies to incorporate new technologies into business plans and to concentrate on the application of open-source product development in the creation of physical goods as a form of competitive advantage.\nNew technologies influence various industries to emphasize innovation as a business tool . Advanced manufacturing is feasible due to continuous improvement investments and modernization of the workforce, technologies and supply chains in order to increase global competitiveness, environmental sustainability and product customization to meet consumer expectations.\nWorkforce.\nIncorporating modern CNC equipment in new manufacturing processes requires better trained employees with more exacting skills than were previously required in heavy industry. Past manufacturing job consisted largely of physical labor and worker assembly line requirements, but in response to technological evolution are becoming tech-savvy and information intense with focus on creativity and resourcefulness.\nStrategy.\nThe new manufacturing economy is centered around \"niche\" businesses who satisfy the needs of small consumer markets by offering what customers want, when they want it. The primary foundation of this strategy is selling less of more. Adopting the efficiencies of digital and Web-based technologies into current business strategies is an emerging trend in manufacturing practices.\nIndustries.\nAdvanced technology in the manufacturing marketplace has led to growth in areas such as software development and biotechnology and to emphasis on numerous industries such as:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "791347", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=791347", "title": "Nesting (process)", "text": "In manufacturing industry, nesting refers to the process of laying out cutting patterns to minimize the raw material waste. Examples include manufacturing parts from flat raw material such as sheet metal, glass sheets, cloth rolls, cutting parts from steel bars, etc.\nSuch process can also be applied to additive manufacturing, such as 3D printing. Here the advantages sought can include minimizing tool movement that is not producing product, or maximizing how many pieces can be fabricated in one build session. One difference from nesting of cut pieces is that 3D parts often have a cross section that changes with height, which can cause interference between adjacent parts as they are built up.\nTypes.\nThe nesting process differs for different types of parts:\nProcess.\nTo minimize the amount of scrap raw material produced during cutting, companies use nesting software. It automates the calculation of ideal distribution of the cutting patterns to avoid waste. The process involves the analyses the parts (shapes) to be produced at a particular time. Using algorithms, it then determines how to lay these parts out in such a way as to produce the required quantities of parts, while minimizing the amount of raw material (or space) wasted. \nOff-the-shelf nesting software packages address the optimization needs. While some cater only to rectangular nesting, others offer profile or shape nesting where the parts required can be any odd shape. These irregular parts can be created using popular computer-aided design (CAD) tools. Here, the nesting software may be utilized as the connection between CAD drawings and the cut output. \nMost of the profile nesting software can read IGES or DXF profile files automatically, a few of them work with built-in converters. An important consideration in shape nesting is to verify that the software in question actually performs true profile nesting and not just block nesting (rectangular). In block nesting an imaginary rectangle is drawn around the shape and then the rectangles are laid side-by side which actually is not profile nesting. There remains scope for waste reduction.\nNesting software must take into account the limitations and features of the material and machining technology in use, such as:\nNesting software may also have to take into account material characteristics, such as:\nMany machine manufacturers offer their own custom nesting software designed to offer ease of use and take full advantage of the features of their specific machines.\nIf a fabricator operates machines from more than one vendor, they may prefer to use an off-the-shelf nesting software package from a third-party vendor. They then have the potential to run jobs on any available machine, and their staff should not have to learn several different software packages.\nSee also.\nMaterial may be cut using off-line blanking dies, lasers, plasma, punches, shear blades, ultrasonic knives and water jet cutters.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "1392108", "revid": "589223", "url": "https://en.wikipedia.org/wiki?curid=1392108", "title": "Slapt-get", "text": "slapt-get is an APT-like package management system for Slackware. Slapt-get tries to emulate the features of Debian's (codice_1) as closely as possible.\nReleased under the terms of the GNU General Public License, slapt-get is free software.\nFeatures.\nslapt-get builds functionality on top of the native Slackware package tools (installpkg, upgradepkg and removepkg) enabling package query, remote fetching, system updates, integrated changelog information, and many optional advanced features such as dependency resolution, package conflicts, suggestions, checksum and public key verification, and transfer resumption.\nslapt-get uses the libcurl cURL library for transport. libcurl provides support for ftp, ftps, http, https, file:// and other resource types along with transfer resume for incomplete downloads. slapt-get also uses the GNU Privacy Guard library to validate signatures.\nslapt-get provides a simple configuration file format that includes an exclusion mechanism for use with the system upgrade option as well as declarations for all desired package sources. Each package source can optionally be tagged with a specific priority in order to override the package version comparison and honor upstream software downgrades as might be the case when Slackware reverts to a previous version of a package.\nDependencies.\nslapt-get does not provide dependency resolution for packages included within the Slackware distribution. It does, however, provide a framework for dependency resolution in Slackware compatible packages similar in fashion to the hand-tuned method APT utilizes. Several package sources and Slackware based distributions take advantage of this functionality. Hard, soft, and conditional dependencies along with package conflicts and complementary package suggestions can be expressed using the slapt-get framework.\nAdding dependency information requires no modification to the packages themselves. Rather, the package listing file, PACKAGES.TXT, is used to specify these relationships. This file is provided by Patrick Volkerding and is similar to the Packages.gz file in use by Debian. Several scripts are available to generate the PACKAGES.TXT file from a group of packages. The file format used by Patrick Volkerding is extended by adding a few extra lines per package. slapt-get then parses this file during source downloads. Typically, third party packages store the dependency information within the package itself for later extraction into the PACKAGES.TXT. The inclusion of this information within the Slackware package format does not inhibit the ability for Slackware pkgtools to install these packages. This information is silently ignored and discarded after the package is installed.\nPackage sources.\nslapt-get works with official Slackware mirrors and third party package repositories such as http://www.slacky.eu/. slapt-get looks for support files, PACKAGES.TXT and CHECKSUMS.md5, in the repository for package information. These files provide package names, versions, sizes (both compressed and uncompressed), checksums, as well as a package description. These files can be extended, as discussed in the previous section, to add dependency listings, conflict information, and package suggestions. These files can also proxy for other remote sources by specifying a MIRROR declaration for each package.\nGSlapt.\nGSlapt is a GTK+ frontend to libslapt, the slapt-get library which provides advanced package management for Slackware and its derivatives. Inspired by the functionality present in Synaptic, Gslapt aims to bring the ease of use enjoyed by Debian and its derivatives to the Slackware world.\nGSlapt was written primarily to supersede the vlapt (x)dialog slapt-get frontend used by VectorLinux.\nDistributions.\nBesides Slackware, slapt-get and GSlapt are included by several other distributions, including:", "Engineering,_Manufacturing": 0.9944306016, "qwen": "Yes"}
{"id": "1393819", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1393819", "title": "Diamond turning", "text": "Diamond turning is turning using a cutting tool with a diamond tip. It is a process of mechanical machining of precision elements using lathes or derivative machine tools (e.g., turn-mills, rotary transfers) equipped with natural or synthetic diamond-tipped tool bits. The term single-point diamond turning (SPDT) is sometimes applied, although as with other lathe work, the \"single-point\" label is sometimes only nominal (radiused tool noses and contoured form tools being options). The process of diamond turning is widely used to manufacture high-quality aspheric optical elements from crystals, metals, acrylic, and other materials. Plastic optics are frequently molded using diamond turned mold inserts. Optical elements produced by the means of diamond turning are used in optical assemblies in telescopes, video projectors, missile guidance systems, lasers, scientific research instruments, and numerous other systems and devices. Most SPDT today is done with computer numerical control (CNC) machine tools. Diamonds also serve in other machining processes, such as milling, grinding, and honing. Diamond turned surfaces have a high specular brightness and require no additional polishing or buffing, unlike other conventionally machined surfaces.\nProcess.\nDiamond turning is a multi-stage process. Initial stages of machining are carried out using a series of CNC lathes of increasing accuracy. A diamond-tipped lathe tool is used in the final stages of the manufacturing process to achieve sub-nanometer level surface finishes and sub-micrometer form accuracies. The surface finish quality is measured as the peak-to-valley distance of the grooves left by the lathe. The form accuracy is measured as a mean deviation from the ideal target form. Quality of surface finish and form accuracy is monitored throughout the manufacturing process using such equipment as contact and laser profilometers, laser interferometers, optical and electron microscopes. Diamond turning is most often used for making infrared optics, because at longer wavelengths optical performance is less sensitive to surface finish quality, and because many of the materials used are difficult to polish with traditional methods.\nTemperature control is crucial, because the surface must be accurate on distance scales shorter than the wavelength of light. Temperature changes of a few degrees during machining can alter the form of the surface enough to have an effect. The main spindle may be cooled with a liquid coolant to prevent temperature deviations.\nThe diamonds that are used in the process are strong in the downhill regime but tool wear is also highly dependent on crystal anisotropy and work material.\nThe machine tool.\nFor best possible quality natural diamonds are used as single-point cutting elements during the final stages of the machining process. A CNC SPDT lathe rests atop a high-quality granite base with micrometer surface finish quality. The granite base is placed on air suspension on a solid foundation, keeping its working surface strictly horizontal. The machine tool components are placed on top of the granite base and can be moved with high degree of accuracy using a high-pressure air cushion or hydraulic suspension. The machined element is attached to an air chuck using negative air pressure and is usually centered manually using a micrometer. The chuck itself is separated from the electric motor that spins it by another air suspension.\nThe cutting tool is moved with sub-micron precision by a combination of electric motors and piezoelectric actuators. As with other CNC machines, the motion of the tool is controlled by a list of coordinates generated by a computer. Typically, the part to be created is first described using a computer aided design (CAD) model, then converted to G-code using a computer aided manufacturing (CAM) program, and the G-code is then executed by the machine control computer to move the cutting tool. The final surface is achieved with a series of cutting passes to maintain a ductile cutting regime.\nAlternative methods of diamond machining in practice also include diamond fly cutting and diamond milling. Diamond fly cutting can be used to generate diffraction gratings and other linear patterns with appropriately contoured diamond shapes. Diamond milling can be used to generate aspheric lens arrays by annulus cutting methods with a spherical diamond tool.\nMaterials.\nDiamond turning is specifically useful when cutting materials that are viable as infrared optical components and certain non-linear optical components such as potassium dihydrogen phosphate (KDP). KDP is a perfect material in application for diamond turning, because the material is very desirable for its optical modulating properties, yet it is impossible to make optics from this material using conventional methods. KDP is water-soluble, so conventional grinding and polishing techniques are not effective in producing optics. Diamond turning works well to produce optics from KDP.\nGenerally, diamond turning is restricted to certain materials. Materials that are readily machinable include:\nThe most often requested materials that are not readily machinable are:\nFerrous materials are not readily machinable because the carbon in the diamond tool chemically reacts with the substrate, leading to tool damage and dulling after short cut lengths. Several techniques have been investigated to prevent this reaction, but few have been successful for long diamond machining processes at mass production scales. \nTool life improvement has been under consideration in diamond turning as the tool is expensive. Hybrid processes such as laser-assisted machining have emerged in this industry recently. The laser softens hard and difficult-to-machine materials such as ceramics and semiconductors, making them easier to cut.\nQuality control.\nDespite all the automation involved in the diamond turning process, the human operator still plays the main role in achieving the final result. Quality control is a major part of the diamond turning process and is required after each stage of machining, sometimes after each pass of the cutting tool. If it is not detected immediately, even a minute error during any of the cutting stages results in a defective part. The extremely high requirements for quality of diamond-turned optics leave virtually no room for error.\nThe SPDT manufacturing process produces a relatively high percentage of defective parts, which must be discarded. As a result, the manufacturing costs are high compared to conventional polishing methods. Even with the relatively high volume of optical components manufactured using the SPDT process, this process cannot be classified as mass production, especially when compared with production of polished optics. Each diamond-turned optical element is manufactured on an individual basis with extensive manual labor.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "1395309", "revid": "45201693", "url": "https://en.wikipedia.org/wiki?curid=1395309", "title": "Electrochemical machining", "text": "Electrochemical machining (ECM) is a method of removing metal by an electrochemical process. It is normally used for mass production and is used for working extremely hard materials or materials that are difficult to machine using conventional methods. Its use is limited to electrically conductive materials. ECM can cut small or odd-shaped angles, intricate contours or cavities in hard and exotic metals, such as titanium aluminides, Inconel, Waspaloy, and high nickel, cobalt, and rhenium alloys. Both external and internal geometries can be machined.\nECM is often characterized as \"reverse electroplating\", in that it removes material instead of adding it. It is similar in concept to electrical discharge machining (EDM) in that a high current is passed between an electrode and the part, through an electrolytic material removal process having a negatively charged electrode (cathode), a conductive fluid (electrolyte), and a conductive workpiece (anode); however, in ECM there is no tool wear. The ECM cutting tool is guided along the desired path close to the work but without touching the piece. Unlike EDM, however, no sparks are created. High metal removal rates are possible with ECM, with no thermal or mechanical stresses being transferred to the part, and mirror surface finishes can be achieved.\nIn the ECM process, a cathode (tool) is advanced into an anode (workpiece). The pressurized electrolyte is injected at a set temperature to the area being cut. The feed rate is the same as the rate of \"liquefication\" of the material. The gap between the tool and the workpiece varies within 80–800 micrometers (0.003–0.030 in.) As electrons cross the gap, material from the workpiece is dissolved, as the tool forms the desired shape in the workpiece. The electrolytic fluid carries away the metal hydroxide formed in the process.\nElectrochemical machining, as a technological method, originated from the process of electrolytic polishing offered already in 1911 by a Russian chemist E.Shpitalsky.\nAs far back as 1929, an experimental ECM process was developed by W.Gussef, although it was 1959 before a commercial process was established by the Anocut Engineering Company. B.R. and J.I. Lazarenko are also credited with proposing the use of electrolysis for metal removal.\nMuch research was done in the 1960s and 1970s, particularly in the gas turbine industry. The rise of EDM in the same period slowed ECM research in the west, although work continued behind the Iron Curtain. The original problems of poor dimensional accuracy and environmentally polluting waste have largely been overcome, although the process remains a niche technique.\nThe ECM process is most widely used to produce complicated shapes such as turbine blades with good surface finish in difficult to machine materials. It is also widely and effectively used as a deburring process.\nIn deburring, ECM removes metal projections left from the machining process, and so dulls sharp edges. This process is fast and often more convenient than the conventional methods of deburring by hand or nontraditional machining processes.\nCurrents involved.\nThe needed current is proportional to the desired rate of material removal, and the removal rate in mm/minute is proportional to the amps per square mm.\nTypical currents range from 0.1 amp per square mm to 5 amps per square mm. Thus, for a small plunge cut of a 1 by 1 mm tool with a slow cut, only 0.1 amps would be needed.\nHowever, for a higher feed rate over a larger area, more current would be used, just like any machining process—removing more material faster takes more power.\nThus, if a current density of 4 amps per square millimeter was desired over a 100×100 mm area, it would take 40,000 amps (and much coolant/electrolyte).\nSetup and equipment.\nECM machines come in both vertical and horizontal types. Depending on the work requirements, these machines are built in many different sizes as well. The vertical machine consists of a base, column, table, and spindle head. The spindle head has a servo-mechanism that automatically advances the tool and controls the gap between the cathode (tool) and the workpiece.\nCNC machines of up to six axes are available.\nCopper is often used as the electrode material. Brass, graphite, and copper-tungsten are also often used because they are easily machined, they are conductive materials, and they will not corrode.\nApplications.\nSome of the very basic applications of ECM include:", "Engineering,_Manufacturing": 1.0000032187, "qwen": "Yes"}
{"id": "1395813", "revid": "13286072", "url": "https://en.wikipedia.org/wiki?curid=1395813", "title": "List of Toyota transmissions", "text": "Toyota Motor Corporation uses many different transmissions in their products. They can be divided into different families.\nAutomatic.\nA-series.\nThe A-series are 2 to 8-speed automatic transmissions for front wheel drive, all wheel drive, or rear wheel drive use built by Aisin-Warner.\nModels:\nU-series.\nThe U-series is an automatic transmission for front wheel drive applications.\nModels:\nCVT.\nK-series.\nThe K-series are CVT transmissions for front wheel drive.\nModels:\nManual.\nC-series.\nThe C-series is a manual transmission for transverse engine applications, front engine front wheel drive and mid-engine rear wheel drive applications, built by Aisin AI, as well in the Elise and Exige.\nModels\nE-series.\nsimilar\nThe E-series transmission for front, mid-engine and all wheel drive applications.\nModels:\nEB-series.\nThe EB-series is a compact 6-speed transmission for front wheel drive applications.\nModels:\nEC-series.\nThe EC-series is a higher-strength compact 6-speed transmission for front and mid-engine applications.\nModels:\nG-series.\nThe G-series is a 4- and 5-speed manual transmission for rear wheel drive and all wheel drive applications, built by Aisin AI and Toyota Autoparts Philippines.\nModels:\nH-series.\nThe H-series is a 4- and 5-speed manual transmission for Land Cruisers and Coaster from 1967–present (?) .\nModels:\nJ-series.\nThe J-series is a 6-speed manual transmission for rear-wheel drive applications, built by Aisin Seiki (Type AZ6). This transmission was used in the Altezza AS200 and RS200. The same Aisin AZ6 transmission is also found in other models such as the Mazda Miata/MX-5/Roadster, Nissan Silvia, Mazda RX-8, Lexus IS and Toyota 86/Scion FR-S/Subaru BRZ.\nModels:\nThere was also a J30 3 speed manual transmission used in 1969-1975 Land Cruisers.\nK-series.\nThe K-series is a 4- and 5-speed manual transmission for small cars.\nModels:\nL-series.\nThe L-series are 4- and 5-speed manual transmissions for rear wheel drive cars and trucks. Not to be confused with the L-series (HSD) hybrid transmissions.\nModels:\nP-series.\nThe P-series is a 5-speed manual transmission for rear wheel drive cars with Porsche-type synchronizers. Not to be confused with the P-series (HSD) hybrid transmissions.\nModels:\nR-series.\nThe R-series is a 5-speed manual transmission for RWD and 4WD vehicles built by Aisin AI, Toyota Autoparts Philippines and Toyota Kirloskar Auto Parts.\nModels:\nRA-series.\nThe RA-series is a 6-speed manual transmission for longitudinally-mounted engines in RWD and 4WD vehicles built by Aisin AI.\nModels:\nRC-series.\nThe RC-series is a 6-speed manual transmission for longitudinally-mounted engines in 4WD vehicles.\nModels:\nS-series.\nThe S-series is a 5-speed manual transmission for front and mid-engine drive applications.\nModels:\nT-series.\nThe T-series is a 4- or 5-speed manual transmission.\nModels:\nW-series.\nThe W-series is a 4- or 5-speed manual transmission built by Aisin AI\nModels:\nV-series.\nThe V-series is a 6-speed manual transmission built by Getrag.\nModels:\nHybrid.\nP-series (HSD).\nThe P-series (HSD) are Hybrid Synergy Drive transmissions used in Toyota and Lexus hybrids for FWD-based platforms.\nModels:\nL-series (HSD).\nThe L-series (HSD) are Hybrid Synergy Drive transmissions used in Toyota and Lexus hybrids for RWD-based platforms.\nModels:", "Engineering,_Manufacturing": 0.9992268085, "qwen": "Yes"}
{"id": "73747009", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=73747009", "title": "Precipitate-free zone", "text": "In materials science, a precipitate-free zone (PFZ) refers to microscopic localized regions around grain boundaries that are free of precipitates (solid impurities forced outwards from the grain during crystallization). It is a common phenomenon that arises in polycrystalline materials (crystalline materials with stochastically-oriented grains) where heterogeneous nucleation of precipitates is the dominant nucleation mechanism. This is because grain boundaries are high-energy surfaces that act as sinks for vacancies, causing regions adjacent to a grain boundary to be devoid of vacancies. As it is energetically favorable for heterogeneous nucleation to occur preferentially around defect-rich sites such as vacancies, nucleation of precipitates is impeded in the vacancy-free regions immediately adjacent to grain boundaries\nHistory.\nPioneering studies on the theory and experimental observation of PFZs were made in the 1960s.\nEffect on material properties.\nPFZs are detrimental to the mechanical properties of materials. In particular, PFZs degrade the material's hardness, because the lack of precipitates in PFZs lead to these regions having fewer pinning sites. Dislocation motion – a condition necessary to cause a material to yield – will require an appreciably lower applied shear stress in PFZs, and consequently these locally weak zones will lead to plastic deformation. The width of PFZs have also been found to be negatively correlated with intergranular fracture\nPFZs also accelerate pitting corrosion and stress corrosion cracking, significantly reducing the usable life of these materials in chemically aggressive environments.\nTechniques to minimize.\nIt has been shown that PFZs can be minimized by quenching. First, quenching increases undercooling, favoring homogeneous nucleation in PFZs as it lowers the nucleation energy barrier even in the absence of potent nucleation sites. Additionally, low temperatures also lead to a reduction in diffusion rates, minimizing the loss of vacancies and premature growth of grain boundary precipitates. However, since diffusion rates at low temperatures are suppressed, the aging time (time taken for treatment to yield a desired grain size) would be long. Therefore, one processing technique to circumvent this is to increase the temperature slightly once a sufficient number of homogeneous nucleation sites have been formed.\nAnother technique to minimize PFZs is to introduce impurity elements, as they strongly interact with vacancies and allow for a more even distribution of vacancies in the material. One example would be to introduce Mg in Al alloys\nCyclic strengthening (CS), a process wherein a material is mechanically pushed and pulled repeatedly at room temperature, creates fine precipitates that is homogeneously distributed throughout the microstructure. It has been suggested as an alternative to conventional, precipitate hardened alloys as this process achieves strengthening effects without introducing PFZs.", "Engineering,_Manufacturing": 0.9977605939, "qwen": "Yes"}
{"id": "3814517", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=3814517", "title": "Plastic milk container", "text": "Plastic milk containers are plastic containers for storing, shipping and dispensing milk. Plastic bottles, sometimes called jugs, have largely replaced glass bottles for home consumption. Glass milk bottles have traditionally been reusable while light-weight plastic bottles are designed for single trips and plastic recycling.\nMaterials.\nPackaging of milk is regulated by regional authorities. Use of food contact materials is required: potential food contamination is prohibited. Strict standards of cleanliness and processing must be followed.\nThe most common material in milk packaging is high density polyethylene (HDPE), recycling code 2. Low density polyethylene (LDPE) and polyester (PET) are also in use. Polycarbonate had been considered but had concerns about potential contamination with bisphenol A.\nContainer forms.\nBlow molded plastic milk bottles have been in use since the 1960s.\nHDPE is the primary material but polyester is also used. A wide variety of milk bottle designs are available. Some have a round cross section while others have a more square or rectangular shape. A special flat-top square milk jug was recently developed to maximize shipping and storing efficiency but had some difficulties in dispensing. Many milk bottles have integral handles.\nMilk bags are also in use. The milk is sold in a plastic bag and put into a pitcher for use. Larger bags are the inner bladder of a Bag-in-box, sometimes used for institutional dispensing.\nSmall individual containers of milk and cream are often thermoformed or injection molded and have a peelable lid. These are often used in restaurants.\nShelf life.\nThe shelf life of pasteurized milk in HDPE bottles and LDPE pouches has been determined to be between 10 and 21 days when stored at 4–8 °C. Other factors such as light and temperature abuse have effects. Shelf life can be extended by ultrapasteurisation and aseptic processing.\nVolume control.\nMilk containers for retail sale must contain the same amount of milk as indicated on the label. To be acceptable to consumers, the containers must also appear to be completely full. Therefore, the volume of the container must be precisely controlled.\nThe designer of a die for a blow moulded bottle can never be completely sure of how much the finished bottle will hold. Shrinkage always occurs after the item is released from the mould. The amount of shrinkage depends upon many factors, including cycle time, inflation air pressure, time in storage prior to filling, storage temperature, and more.\nA volume adjuster insert is one way to slightly adjust the volume of a bottle, without building a completely new mould. A volume insert attaches to the inside of a mould, creating a circular indentation on the side of the finished bottle. Different size inserts can be used as manufacturing circumstances change, for example mould temperature or cooling rate. The volume of finished bottles is periodically measured, and volume inserts are changed as needed.\nEnvironmental comparisons.\nMany potential factors are involved in environmental comparisons of returnable vs non-returnable systems. Researchers have often used life cycle analysis methodologies to balance the many diverse considerations. Often the comparisons show benefits and problems with all alternatives. One recent life cycle study of one-way recyclable HDPE bottles indicated the importance of secondary packaging: returnable plastic crates can allow lower tare weight bottles.\nReuse of bottles requires a reverse logistics system, cleaning and, sanitizing bottles, and an effective Quality Management System. A key factor with glass milk bottles is the number of cycles of uses to be expected. Breakage, contamination, or other loss reduces the benefits of returnables. A key factor with one-way recyclables is the recycling rate: In the US, only about 30–35% of HDPE bottles are recycled.", "Engineering,_Manufacturing": 0.9999819994, "qwen": "Yes"}
{"id": "3818247", "revid": "42204915", "url": "https://en.wikipedia.org/wiki?curid=3818247", "title": "Electronic kit", "text": "An electronic kit is a package of electrical components used to build an electronic device. Generally, kits are composed of electronic components, a circuit diagram (schematic), assembly instructions, and often a printed circuit board (PCB) or another type of prototyping board.\nThere are two types of kits. Some build a single device or system. Other types used for education demonstrate a range of circuits. These will include a solderless construction board of some type, such as:\nThe first type of kit for constructing a single device normally uses a PCB on which components are soldered. They normally come with extended documentation describing which component goes where into the PCB.\nFor advanced hobby projects, sometimes the kit may only consist of a printed circuit board and assembly instructions, and the purchaser may have to source all the parts independently; or, the vendor may provide hard-to-get or pre-programmed parts while expecting the purchaser to obtain the rest of the components.\nPeople primarily purchase electronic kits to have fun and learn how things work. They were once popular as a means to reduce the cost of buying goods, but there is usually no cost saving in buying a kit today.\nSome electronic kits were assembled to make complete complex devices such as color television sets, oscilloscopes, high-end audio amplifiers, amateur radio equipment, electric organs, and even computers such as the Heathkit H-8, and the LNW-80. Many of the early microprocessor computers were sold as either electronic kits or assembled and tested. Heathkit sold millions of electronic kits during its 45-year history.\nHome assembly of common consumer electronics items no longer provides a cost advantage over commercially manufactured and distributed devices. People still build kits for custom devices and special-purpose electronics for professional and educational use and as a hobby.\nAlso emerging is a trend to simplify the complexity by providing preprogrammed or modular kits often provided by many suppliers online. The fun and thrill of making your own electronics have shifted, in many cases, from easy-to-comprehend applications and analog devices to more sophisticated digital devices.", "Engineering,_Manufacturing": 0.9988119602, "qwen": "Yes"}
{"id": "3824182", "revid": "5839411", "url": "https://en.wikipedia.org/wiki?curid=3824182", "title": "Hole saw", "text": "A hole saw (also styled holesaw), also known as a hole cutter, is a saw blade of annular (ring) shape, whose annular kerf creates a hole in the workpiece without having to cut up the core material. It is used in a drill. Hole saws typically have a pilot drill bit (arbor) at their center to keep the saw teeth from walking. The fact that a hole saw creates the hole without needing to cut up the core often makes it preferable to twist drills or spade drills for relatively large holes (especially those larger than . The same hole can be made faster and using less power.\nThe depth to which a hole saw can cut is limited by the depth of its cup-like shape. Most hole saws have a fairly short aspect ratio of diameter to depth, and they are used to cut through relatively thin workpieces. However, longer aspect ratios are available for applications that warrant them. Common hole saw depths are 38, 45 and 60 mm and for drilling through e.g. (angled-) rooftop constructions also a depth 165 and 300 mm is possible.\nCutting with a hole saw is analogous to some machining operations, called \"trepanning\" in the trade, that swing a cutter analogous to a fly cutter in order to achieve a similar result of annular kerf and intact core.\nConstruction.\nThe saw consists of a metal cylinder, usually steel, mounted on an arbor. The cutting edge either has saw teeth formed in it or industrial diamonds embedded in it. The arbor can carry a drill bit to bore a centering hole. After the first few millimeters of cut, the centering mechanism may no longer be needed, although it will help the bit to bore without wandering in a deep hole. The sloping slots in the cylinder wall help carry the dust out. The kerf of the cut is designed to be slightly larger than the diameter of the rest of the hole saw so that it does not get jammed in the hole.\nHoles saws for use with portable drills are commonly available in diameters from 6 to 130 mm, or in the US, ¼ to 6 inches. The only limit on the length of the cylinder, and thus depth of the hole, is the need to remove the bit from the hole to clear dust. A cylinder length is not uncommon, although shorter bits are usual. By breaking the core off from time to time and using a shank extension, a diamond core drill can drill to depths many times its length.\nSaw teeth are used for most materials, such as wood, plastic, soft plaster, and metal. Diamond hole saws are used to bore holes in brick, concrete, glass, and stone.\nTypes.\nAdjustable.\nAn adjustable hole saw consists of a number of thin metal saw blade-like strips, and a flat disc with a large number of grooves in one side and a shank on the other. By snapping the blades into different grooves on the disc, a hole saw of a wide variety of sizes can be constructed.\nCircle cutter.\nAnother type of adjustable hole saw, also called a circle cutter, is formed by having one, two, or three adjustable teeth on a platform with a pilot bit. To cut out a hole of any size, the teeth need only be adjusted to the proper position. This type is available in sizes up to and larger, and can be used to accurately cut large circles.\nAdvantages and disadvantages.\nThe main advantage over conventional drill bits is the hole saw's efficiency, because very little of the total material being removed is actually cut, which ultimately reduces the overall power requirement. Another advantage over drill bits is the wider size capability. For example, a hole would require a huge twist drill or spade drill, unable to be properly driven by a pistol-grip drill or benchtop drill press; but it can be cut with a hole saw with relative ease.\nSome disadvantages include:\nDiamond drilling.\nDiamond hole saws are also called diamond core drill bits. Laser welded diamond core drill bits can be used in wet and dry drilling, but not all materials to be drilled are suitable for dry drilling. Very hard materials like reinforced concrete normally should be drilled with water, otherwise the excessive heat generated during the drilling process may cause the diamonds on the core bit to become blunt, and then lead to poor drilling performance.\nThe bond materials welded diamond core drill bits usually are specially adjusted to fit the wet and dry drillings respectively. This can make the core bits perform better in drilling speed and/or lifespan.\nDiamond hole saws will drill through tile, porcelain tiles, granite, marble, concrete, metals and any lapidary material.", "Engineering,_Manufacturing": 0.999677062, "qwen": "Yes"}
{"id": "25060566", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=25060566", "title": "Knockout punch", "text": "In metalworking, a knockout punch, also known as a chassis punch, panel punch, Greenlee punch, or a Q-max, is a hand tool used to punch a hole through sheet metal. It is a very simple tool that consists of a punch, die, and screw. There are three different drive systems: manual, ratchet, and hydraulic.\nOperation.\nFirst a pilot hole is drilled slightly larger than the screw of the knockout punch. Then the die is placed on the screw and the screw is inserted into the pilot hole. The screw is then threaded into the punch and the screw tightened until the punch is drawn completely through the sheet metal.\nThe manual system uses a screw that has a standard hex head or square head and is driven using an allen key or wrench. A manual knockout punch can handle holes from . The ratchet system has a custom ratcheting wrench that uses a ball screw to make the process faster and easier. This type of system has a mechanical advantage of approximately 220:1 and can punch holes up to in diameter in 10 gauge mild steel. A hydraulic system is much bulkier and heavier than the other systems but it is the easiest to use and can make holes up to in diameter. It is a two piece system where the dies are attached to the ram which is connected to the hydraulic unit via a flexible hose.\nSize families and shapes.\nThere are several sizing systems for these punches. The two most common are those sized for standard electrical knockout sizes and those that are for true dimensional holes. A 3/4 inch conduit size punch actually punches a hole that is approximately 1.1 inches diameter for 3/4 nominal size conduit. A dimensional size punch makes a hole very close to the indicated size. Punch sets are available on both imperial and metric sizes.\nChassis punches are available in a number of shapes, round being the most common. Other shapes include square, hexagonal, and special shapes for thing such as holes with key tabs and D-sub connectors Special shapes often use bolts that are square or keyed and a separate nut on the punch end to ensure alignment of the punch and die.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "25062338", "revid": "6289403", "url": "https://en.wikipedia.org/wiki?curid=25062338", "title": "Monomotor", "text": "A monomotor is a train design where a single traction motor powers two or three axles in the same bogie. Conventional bogie design involves either having one motor for each axle, or having one or more axles unpowered. The monomotor design causes the motor to give both axles the same number of revolutions per minute.\nAdvantages.\nThe monomotor design makes it relatively easy to fit a locomotive with two-speed gearing. Low gear is used when hauling freight trains and high gear is used when hauling express passenger trains.\nPotential problems.\nWhen both axle's wheels are equally worn, this gives good operating conditions but, as soon as one of the wheels becomes slightly more worn (as is inevitable with steel wheels on steel rails), there will be slippage which causes wear and waste of energy. The problem can be countered by keeping the wheels regularly ground to the same diameter.", "Engineering,_Manufacturing": 1.0000058413, "qwen": "Yes"}
{"id": "25067088", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=25067088", "title": "Soldering", "text": "Soldering  is a process of joining two metal surfaces together using a filler metal called solder. The soldering process involves heating the surfaces to be joined and melting the solder, which is then allowed to cool and solidify, creating a strong and durable joint.\nSoldering is commonly used in the electronics industry for the manufacture and repair of printed circuit boards (PCBs) and other electronic components. It is also used in plumbing and metalwork, as well as in the manufacture of jewelry and other decorative items.\nThe solder used in the process can vary in composition, with different alloys used for different applications. Common solder alloys include tin-lead, tin-silver, and tin-copper, among others. Lead-free solder has also become more widely used in recent years due to health and environmental concerns associated with the use of lead.\nIn addition to the type of solder used, the temperature and method of heating also play a crucial role in the soldering process. Different types of solder require different temperatures to melt, and heating must be carefully controlled to avoid damaging the materials being joined or creating weak joints.\nThere are several methods of heating used in soldering, including soldering irons, torches, and hot air guns. Each method has its own advantages and disadvantages, and the choice of method depends on the application and the materials being joined.\nSoldering is an important skill for many industries and hobbies, and it requires a combination of technical knowledge and practical experience to achieve good results. \nOrigins.\nThere is evidence that soldering was employed as early as 5,000 years ago in Mesopotamia. Soldering and brazing are thought to have originated very early in the history of metal-working, probably before 4000 BC. Sumerian swords from were assembled using hard soldering.\nSoldering was historically used to make jewelry, cookware and cooking tools, assembling stained glass, as well as other uses.\nApplications.\nSoldering is used in plumbing, electronics, and metalwork from flashing to jewelry and musical instruments.\nSoldering provides reasonably permanent but reversible connections between copper pipes in plumbing systems as well as joints in sheet metal objects such as food cans, roof flashing, rain gutters and automobile radiators.\nJewelry components, machine tools and some refrigeration and plumbing components are often assembled and repaired by the higher temperature silver soldering process. Small mechanical parts are often soldered or brazed as well. Soldering is also used to join lead came and copper foil in stained glass work.\nElectronic soldering connects electrical wiring to devices, and electronic components to printed circuit boards. Electronic connections may be hand-soldered with a soldering iron. Automated methods such as wave soldering or use of ovens can make many joints on a complex circuit board in one operation, vastly reducing production cost of electronic devices.\nMusical instruments, especially brass and woodwind instruments, use a combination of soldering and brazing in their assembly. Brass bodies are often soldered together, while keywork and braces are most often brazed.\nSolderability.\nThe solderability of a substrate is a measure of the ease with which a soldered joint can be made to that material.\nSome metals are easier to solder than others. Copper, zinc, brass, silver and gold are easy. Iron, mild steel and nickel are next in difficulty. Because of their thin, strong oxide films, stainless steel and some aluminium alloys are even more difficult to solder. Titanium, magnesium, cast irons, some high-carbon steels, ceramics, and graphite can be soldered but it involves a process similar to joining carbides: they are first plated with a suitable metallic element that induces interfacial bonding.\nSolders.\nSoldering filler materials are available in many different alloys for differing applications. In electronics assembly, the eutectic alloy with 63% tin and 37% lead (or 60/40, which is almost identical in melting point) has been the alloy of choice. Other alloys are used for plumbing, mechanical assembly, and other applications. Some examples of soft-solder are tin-lead for general purposes, tin-zinc for joining aluminium, lead-silver for strength at higher than room temperature, cadmium-silver for strength at high temperatures, zinc-aluminium for aluminium and corrosion resistance, and tin-silver and tin-bismuth for electronics.\nA eutectic formulation has advantages when applied to soldering: the liquidus and solidus temperatures are the same, so there is no plastic phase, and it has the lowest possible melting point. Having the lowest possible melting point minimizes heat stress on electronic components during soldering. And, having no plastic phase allows for quicker wetting as the solder heats up, and quicker setup as the solder cools. A non-eutectic formulation must remain still as the temperature drops through the liquidus and solidus temperatures. Any movement during the plastic phase may result in cracks, resulting in an unreliable joint.\nCommon solder formulations based on tin and lead are listed below. The fraction represent percentage of tin first, then lead, totaling 100%:\nFor environmental reasons and the introduction of regulations such as the European RoHS (Restriction of Hazardous Substances Directive), lead-free solders are becoming more widely used. They are also suggested anywhere young children may come into contact with (since young children are likely to place things into their mouths), or for outdoor use where rain and other precipitation may wash the lead into the groundwater. Unfortunately, common lead-free solders are not eutectic formulations, melting at around , making it more difficult to create reliable joints with them.\nOther common solders include low-temperature formulations (often containing bismuth), which are often used to join previously soldered assemblies without unsoldering earlier connections, and high-temperature formulations (usually containing silver) which are used for high-temperature operation or for first assembly of items which must not become unsoldered during subsequent operations. Alloying silver with other metals changes the melting point, adhesion and wetting characteristics, and tensile strength. Of all the brazing alloys, silver solders have the greatest strength and the broadest applications. Specialty alloys are available with properties such as higher strength, the ability to solder aluminum, better electrical conductivity, and higher corrosion resistance.\nSoldering vs. brazing.\nThere are three forms of soldering, each requiring progressively higher temperatures and producing an increasingly stronger joint strength:\nThe alloy of the filler metal for each type of soldering can be adjusted to modify the melting temperature of the filler. Soldering differs from gluing significantly in that the filler metals directly bond with the surfaces of the workpieces at the junction to form a bond that is both electrically conductive and gas- and liquid-tight.\nSoft soldering is characterized by having a melting point of the filler metal below approximately , whereas silver soldering and brazing use higher temperatures, typically requiring a flame or carbon arc torch to achieve the melting of the filler. Soft solder filler metals are typically alloys (often containing lead) that have liquidus temperatures below .\nIn this soldering process, heat is applied to the parts to be joined, causing the solder to melt and to bond to the workpieces in a surface alloying process called wetting. In stranded wire, the solder is drawn up into the wire between the strands by capillary action in a process called 'wicking'. Capillary action also takes place when the workpieces are very close together or touching. The joint's tensile strength is dependent on the filler metal used; in electrical soldering little tensile strength comes from the added solder which is why it is advised that wires be twisted or folded together before soldering to provide some mechanical strength for a joint. A good solder joint produces an electrically conductive, water- and gas-tight join.\nEach type of solder offers advantages and disadvantages. Soft solder is so called because of the soft lead that is its primary ingredient. Soft soldering uses the lowest temperatures (and so thermally stresses components the least) but does not make a strong joint and is unsuitable for mechanical load-bearing applications. It is also unsuitable for high-temperature applications as it loses strength, and eventually melts. Silver soldering, as used by jewelers, machinists and in some plumbing applications, requires the use of a torch or other high-temperature source, and is much stronger than soft soldering. Brazing provides the strongest of the non-welded joints but also requires the hottest temperatures to melt the filler metal, requiring a torch or other high temperature source and darkened goggles to protect the eyes from the bright light produced by the white-hot work. It is often used to repair cast-iron objects, wrought-iron furniture, etc.\nSoldering operations can be performed with hand tools, one joint at a time, or \"en masse\" on a production line. Hand soldering is typically performed with a soldering iron, soldering gun, or a torch, or occasionally a hot-air pencil. Sheetmetal work was traditionally done with \"soldering coppers\" directly heated by a flame, with sufficient stored heat in the mass of the soldering copper to complete a joint; gas torches (e.g. butane or propane) or electrically heated soldering irons are more convenient. All soldered joints require the same elements of cleaning of the metal parts to be joined, fitting up the joint, heating the parts, applying flux, applying the filler, removing heat and holding the assembly still until the filler metal has completely solidified. Depending on the nature of flux material used and the application, cleaning of the joint may be required after it has cooled.\nEach solder alloy has characteristics that work best for certain applications, notably strength and conductivity, and each type of solder and alloy has different melting temperatures. The term \"silver solder\" denotes the type of solder that is used. Some soft solders are \"silver-bearing\" alloys used to solder silver-plated items. Lead-based solders should not be used on precious metals because the lead dissolves the metal and disfigures it.\nThe distinction between soldering and brazing is based on the melting temperature of the filler alloy. A temperature of 450 °C is usually used as a practical demarcation between soldering and brazing. Soft soldering can be done with a heated iron whereas the other methods typically require a higher temperature torch or a furnace to melt the filler metal.\nDifferent equipment is usually required since a soldering iron cannot achieve high enough temperatures for hard soldering or brazing. Brazing filler metal is stronger than silver solder, which is stronger than lead-based soft solder. Brazing solders are formulated primarily for strength, silver solder is used by jewelers to protect the precious metal and by machinists and refrigeration technicians for its tensile strength but lower melting temperature than brazing, and the primary benefit of soft solder is the low temperature used (to prevent heat damage to electronic components and insulation).\nSince the joint is produced using a metal with a lower melting temperature than the workpiece, the joint will weaken as the ambient temperature approaches the melting point of the filler metal. For that reason, the higher temperature processes produce joints which are effective at higher temperatures. Brazed connections can be as strong or nearly as strong as the parts they connect, even at elevated temperatures.\nSilver soldering.\n\"Hard soldering\" or \"silver soldering\" is used to join precious and semi-precious metals such as gold, silver, brass, and copper. The solder is usually described as easy, medium, or hard in reference to its melting temperature, not the strength of the joint. Extra-easy solder contains 56% silver and has a melting point of . Extra-hard solder has 80% silver and melts at . If multiple joints are needed, then the jeweler will start with hard or extra-hard solder and switch to lower-temperature solders for later joints.\nSilver solder is somewhat absorbed by the surrounding metal, resulting in a joint that is actually stronger than the metal being joined. The metal being joined must be perfectly flush, as silver solder cannot normally be used as a filler and will not fill gaps.\nAnother difference between brazing and soldering is how the solder is applied. In brazing, one generally uses rods that are touched to the joint while being heated. With silver soldering, small pieces of solder wire are placed onto the metal prior to heating. A flux, often made of boric acid and denatured alcohol, is used to keep the metal and solder clean and to prevent the solder from moving before it melts.\nWhen silver solder melts, it tends to flow towards the area of greatest heat. Jewelers can somewhat control the direction the solder moves by leading it with a torch; it will even sometimes run straight up along a seam.\nMechanical and aluminium soldering.\nA number of solder materials, primarily zinc alloys, are used for soldering aluminium metal and alloys and to a lesser extent steel and zinc. This mechanical soldering is similar to a low temperature brazing operation, in that the mechanical characteristics of the joint are reasonably good and it can be used for structural repairs of those materials.\nThe American Welding Society defines brazing as using filler metals with melting points over — or, by the traditional definition in the United States, above . Aluminium soldering alloys generally have melting temperatures around . This soldering / brazing operation can use a propane torch heat source.\nThese materials are often advertised as \"aluminium welding\", but the process does not involve melting the base metal, and therefore is not properly a weld.\nUnited States Military Standard or MIL-SPEC specification MIL-R-4208 defines one standard for these zinc-based brazing/soldering alloys. A number of products meet this specification. or very similar performance standards.\nFlux.\nThe purpose of flux is to facilitate the soldering process. One of the obstacles to a successful solder joint is an impurity at the site of the joint; for example, dirt, oil or oxidation. The impurities can be removed by mechanical cleaning or by chemical means, but the elevated temperatures required to melt the filler metal (the solder) encourages the work piece (and the solder) to re-oxidize. This effect is accelerated as the soldering temperatures increase and can completely prevent the solder from joining to the workpiece. One of the earliest forms of flux was charcoal, which acts as a reducing agent and helps prevent oxidation during the soldering process. Some fluxes go beyond the simple prevention of oxidation and also provide some form of chemical cleaning (corrosion). Many fluxes also act as a wetting agent in the soldering process, reducing the surface tension of the molten solder and causing it to flow and wet the workpieces more easily.\nFor many years, the most common type of flux used in electronics (soft soldering) was rosin-based, using the rosin from selected pine trees. It was nearly ideal in that it was non-corrosive and non-conductive at normal temperatures but became mildly reactive (corrosive) at elevated soldering temperatures. Plumbing and automotive applications, among others, typically use an acid-based (hydrochloric acid) flux which provides rather aggressive cleaning of the joint. These fluxes cannot be used in electronics because their residues are conductive leading to unintended electrical connections, and because they will eventually dissolve small diameter wires. Citric acid is an excellent water-soluble acid-type flux for copper and electronics but must be washed off afterwards.\nFluxes for soft solder are currently available in three basic formulations:\nFlux performance must be carefully evaluated for best results; a very mild 'no-clean' flux might be perfectly acceptable for production equipment, but not give adequate performance for more variable hand-soldering operations.\nHeating methods.\nDifferent types of soldering tools are made for specific applications. The required heat can be generated from burning fuel or from an electrically operated heating element or by passing an electric current through the item to be soldered. Another method for soldering is to place solder and flux at the locations of joints in the object to be soldered, then heat the entire object in an oven to melt the solder; toaster ovens and hand-held infrared lights have been used by hobbyists to replicate production soldering processes on a much smaller scale. A third method of soldering is to use a solder pot where the part (with flux) is dipped in a small heated iron cup of liquid solder, or a pump in a bath of liquid solder produces an elevated \"wave\" of solder which the part is quickly passed through. Wave soldering uses surface tension to keep solder from bridging the insulating gaps between the copper lines of flux-coated printed wiring boards/printed circuit boards.\nThe electric soldering iron is widely used for hand-soldering, consisting of a heating element in contact with the \"iron\" (a larger mass of metal, usually copper) which is in contact with the working tip made of copper. Usually, soldering irons can be fitted with a variety of tips, ranging from blunt, to very fine, to chisel heads for hot-cutting plastics rather than soldering. Plain copper tips are subject to errosion/dissolution in hot solder, and may be plated with pure iron to prevent that. The simplest irons do not have temperature regulation. Small irons rapidly cool when used to solder to, say, a metal chassis, while large irons have tips too cumbersome for working on printed circuit boards (PCBs) and similar fine work. A 25-watt iron will not provide enough heat for large electrical connectors, joining copper roof flashing, or large stained-glass lead came. On the other hand, a 100-watt iron may provide too much heat for PCBs. Temperature-controlled irons have a reserve of power and can maintain temperature over a wide range of work.\nA soldering gun heats a small cross-section copper tip very quickly by conducting a large AC current through it using a large cross-section one-turn transformer; the copper tip then conducts the heat to the part like other soldering irons. A soldering gun will be larger and heavier than a heating-element soldering iron of the same power rating because of the built-in transformer. \nGas-powered irons using a catalytic tip to heat a bit, without flame, are used for portable applications. Hot-air guns and pencils allow rework of component packages (such as surface mount devices) which cannot easily be performed with electric irons and guns.\nFor non-electronic applications, soldering torches use a flame rather than a soldering tip to heat solder. Soldering torches are often powered by butane and are available in sizes ranging from very small butane/oxygen units suitable for very fine but high-temperature jewelry work, to full-size oxy-fuel torches suitable for much larger work such as copper piping. Common multipurpose propane torches, the same kind used for heat-stripping paint and thawing pipes, can be used for soldering pipes and other fairly large objects either with or without a soldering tip attachment; pipes are generally soldered with a torch by directly applying the open flame.\nA soldering copper is a tool with a large copper head and a long handle which is heated with a small direct flame and used to apply heat to sheet metal such as tin plated steel for soldering. Typical soldering coppers have heads weighing between one and four pounds. The head provides a large thermal mass to store enough heat for soldering large areas before needing re-heating in the fire; the larger the head, the longer the working time. The copper surface of the tool must be constantly cleaned and re-tinned during use. Historically, soldering coppers were standard tools used in auto bodywork, although body solder has been mostly superseded by spot welding for mechanical connection, and non-metallic fillers for contouring.\nDuring WW2 and for some time afterwards SOE forces used small pyrotechnic self-soldering joints to make connections for the remote detonation of demolition and sabotage explosives. These consisted of a small copper tube partially filled with solder and a slow-burning pyrotechnic composition wrapped around the tube. The wires to be joined would be inserted into the tube and a small blob of ignition compound allowed the device to be struck like a match to ignite the pyrotechnic and heat the tube for long enough to melt the solder and make the joint.\nLaser soldering.\n\"Laser soldering\" is a technique where a 30–50 W laser is used to melt and solder an electrical connection joint. Diode laser systems based on semiconductor junctions are used for this purpose. Suzanne Jenniches patented laser soldering in 1980.\nWavelengths are typically 808 nm through 980 nm. The beam is delivered via an optical fiber to the workpiece, with fiber diameters 800 µm and smaller. Since the beam out of the end of the fiber diverges rapidly, lenses are used to create a suitable spot size on the workpiece at a suitable working distance. A wire feeder is used to supply solder.\nBoth lead-tin and silver-tin material can be soldered. Process recipes will differ depending on the alloy composition. For soldering 44-pin chip carriers to a board using soldering preforms, power levels were on the order of 10 watts and solder times approximately 1 second. Low power levels can lead to incomplete wetting and the formation of voids, both of which can weaken the joint.\nPhotonic soldering.\nPhotonic soldering is a relatively new process that uses broadband light from rapidly pulsing flashlamps to solder components to a circuit board. Energy consumption is approximately 85% less than that of a reflow oven, while the throughput is higher, and the footprint is smaller. It is similar to photonic curing, in that the components to be soldered are heated while the substrate remains relatively cool. This enables the use of high-temperature solders, such as SAC305, even on thermally fragile substrates such as PET, cellulose, and fabrics. An entire circuit board can be processed in a few seconds. In some cases, masks are used, but it can also be performed without registration, enabling very high processing rates.\nInduction soldering.\nInduction soldering uses induction heating by high-frequency alternating current in a surrounding copper coil. This induces currents in the part being soldered, which generates heat because of the higher resistance of a joint versus its surrounding metal (resistive heating). These copper coils can be shaped to fit the joint more precisely. A filler metal (solder) is placed between the facing surfaces, and this solder melts at a fairly low temperature. Fluxes are commonly used in induction soldering. This technique is particularly suited to continuously soldering, in which case these coils wrap around a cylinder or a pipe that needs to be soldered.\nFiber focus infrared soldering.\nFiber focus infrared soldering is technique where many infrared sources are led through fibers, then focused onto a single spot at which the connection is soldered.\nResistance soldering.\nResistance soldering is soldering in which the heat required to melt the solder is created by passing an electric current through the parts to be soldered. When electric current is conducted through any metal, heat is generated; when that current is confined to a smaller cross-sectional area, the heat produced in the entire circuit is concentrated in the portion with the reduced cross-sectional area. The current doing the heating is applied by electrodes or tips energized from a low (open-circuit) voltage source, typically 2-7 volts. They can be tweezer-like for general connections or specially-shaped to make contact with parts located closely together.\nResistance soldering is unlike using a conduction iron, where heat is produced within an element and then passed through a thermally conductive tip into the joint area. A cold soldering iron requires time to reach working temperature and must be kept hot between solder joints. Thermal transfer may be inhibited if the tip is not kept properly wetted during use. With resistance soldering an intense heat can be rapidly developed directly within the joint area and in a tightly controlled manner. This allows a faster ramp up to the required solder melt temperature and minimizes thermal travel away from the solder joint, which helps to minimize the potential for thermal damage to materials or components in the surrounding area. Heat is only produced while each joint is being made, making resistance soldering more energy efficient. Because of these advantages, resistance soldering is common in industries which solder in small spaces such as connectors and wire terminals, and where high power is required, such as desoldering automotive parts.\nResistance soldering equipment, unlike conduction irons, can be used for difficult soldering and brazing applications where significantly higher temperatures may be required. This makes resistance comparable to flame soldering in some situations, but the resistance heat is more localized because of direct contact, whereas the flame might heat a larger area.\nActive soldering.\nFlux-less soldering with aid of conventional soldering iron, ultrasonic soldering iron or specialized solder pot and active solder that contains an active element, most often titanium, zirconium or chromium. The active elements, owing to mechanical activation, react with the surface of the materials generally considered difficult to solder without premetallization. The active solders can be protected against excessive oxidation of their active element by addition of rare-earth elements with higher affinity to oxygen (typically cerium or lanthanum). Another common additive is gallium – usually introduced as a wetting promoter. Mechanical activation, needed for active soldering, can be performed by brushing (for example with use of stainless wire brush or steel spatula) or ultrasonic vibration (20–60 kHz). Active soldering has been shown to effectively bond ceramics, aluminium, titanium, silicon, graphite and carbon nanotube based structures at temperatures lower than 450 °C or use of protective atmosphere.\nPipe soldering.\nCopper pipe, or 'tube', is commonly joined by soldering. When applied in a plumbing trade context in the United States, soldering is often referred to as \"sweating\", and a tubing connection so made is referred to as a \"sweated joint\".\nOutside the United States, \"sweating\" refers to the joining of flat metallic surfaces by a two step process by which solder is first applied to one surface, then this first piece is placed in position against the second surface and both are re-heated to achieve the desired joint.\nCopper tubing conducts heat away much faster than a conventional hand-held soldering iron or gun can provide, so a propane torch is most commonly used to deliver the necessary power; for large tubing sizes and fittings a MAPP-fueled, acetylene-fueled, or propylene-fueled torch is used with atmospheric air as the oxidizer; MAPP/oxygen or acetylene/oxygen are rarely used because the flame temperature is much higher than the melting point of copper. Too much heat destroys the temper of hard-tempered copper tubing, and can burn the flux out of a joint before the solder is added, resulting in a faulty joint. For larger tubing sizes, a torch fitted with various sizes of interchangeable \"swirl tips\" is employed to deliver the needed heating power. In the hands of a skilled tradesman, the hotter flame of acetylene, MAPP, or propylene allows more joints to be completed per hour without damage to copper tempering.\nHowever, it is possible to use an electrical tool to solder joints in copper pipe sized from . For example, the Antex Pipemaster is recommended for use in tight spaces, when open flames are hazardous, or by do-it-yourself users. The pliers-like tool uses heated fitted jaws that completely encircle the pipe, allowing a joint to be melted in as little as 10 seconds.\nSolder fittings, also known as 'capillary fittings', are usually used for copper joints. These fittings are short sections of smooth pipe designed to slide over the outside of the mating tube. Commonly used fittings include for straight connectors, reducers, bends, and tees. There are two types of solder fittings: 'end feed fittings' which contain no solder, and 'solder ring fittings' (also known as Yorkshire fittings), in which there is a ring of solder in a small circular recess inside the fitting.\nAs with all solder joints, all parts to be joined must be clean and oxide free. Internal and external wire brushes are available for the common pipe and fitting sizes; emery cloth and wire-wool are frequently used as well, although metal wool products are discouraged, as they can contain oil, which would contaminate the joint.\nBecause of the size of the parts involved, and the high activity and contaminating tendency of the flame, plumbing fluxes are typically much more chemically active, and often more acidic, than electronic fluxes. Because plumbing joints may be done at any angle, even upside down, plumbing fluxes are generally formulated as pastes which stay in place better than liquids. Flux is applied to all surfaces of the joint, inside and out. Flux residues are removed after the joint is complete to prevent erosion and failure of the joint.\nMany plumbing solder formulations are available, with different characteristics, such as higher or lower melting temperature, depending on the specific requirements of the job. Building codes currently almost universally require the use of lead-free solder for drinking water piping (and also flux must be approved for drinking water applications), though traditional tin-lead solder is still available. Studies have shown that lead-soldered plumbing pipes can result in elevated levels of lead in drinking water.\nSince copper pipe quickly conducts heat away from a joint, great care must be taken to ensure that the joint is properly heated through to obtain a good bond. After the joint is properly cleaned, fluxed and fitted, the torch flame is applied to the thickest part of the joint, typically the fitting with the pipe inside it, with the solder applied at the gap between the tube and the fitting. When all the parts are heated through, the solder will melt and flow into the joint by capillary action. The torch may need to be moved around the joint to ensure all areas are wetted out. However, the installer must take care to not overheat the areas being soldered. If the tube begins to discolor it means that the tube has been over-heated and is beginning to oxidize, stopping the flow of the solder and causing the soldered joint not to seal properly. Before oxidation the molten solder will follow the heat of the torch around the joint. When the joint is properly wetted out, the solder and then the heat are removed, and while the joint is still very hot, it is usually wiped with a dry rag. This removes excess solder as well as flux residue before it cools down and hardens. With a solder ring joint, the joint is heated until a ring of molten solder is visible around the edge of the fitting and allowed to cool.\nOf the three methods of connecting copper tubing, solder connections require the most skill, but soldering copper is a very reliable process, provided some basic conditions are met:\nCopper is only one material that is joined in this manner. Brass fittings are often used for valves or as a connection fitting between copper and other metals. Brass piping is soldered in this manner in the making of brass instruments and some woodwind (saxophone and flute) musical instruments\nWire brush, wire wool and emery cloth are commonly used to prepare plumbing joints for connection. Bristle brushes are usually used to apply plumbing paste flux. A heavy rag is usually used to remove flux from a plumbing joint before it cools and hardens. A fiberglass brush can also be used.\nWhen soldering pipes closely connected to valves such as in refrigeration systems it may be necessary to protect the valve from heat that could damage rubber or plastic components within, in this case a wet cloth wrapped around the valve can often sink sufficient heat through the boiling of the water to protect the valve.\nCopper tube soldering defects.\nIn the joining of copper tube, failure to properly heat and fill a joint may lead to a 'void' being formed. This is usually a result of improper placement of the flame. If the heat of the flame is not directed at the back of the fitting cup, and the solder wire applied degrees opposite the flame, then solder will quickly fill the opening of the fitting, trapping some flux inside the joint. This bubble of trapped flux is the void; an area inside a soldered joint where solder is unable to completely fill the fittings' cup, because flux has become sealed inside the joint, preventing solder from occupying that space.\nStained glass soldering.\nHistorically, stained glass soldering tips were copper, heated by being placed in a charcoal-burning brazier. Multiple tips were used; when one tip cooled down from use, it was placed back in the brazier of charcoal and the next tip was used.\nMore recently, electrically heated soldering irons are used. These are heated by a coil or ceramic heating element inside the tip of the iron. Different power ratings are available, and temperature can be controlled electronically. These characteristics allow longer beads to be run without interrupting the work to change tips. Soldering irons designed for electronic use are often effective though they are sometimes underpowered for the heavy copper and lead came used in stained glass work.\nOleic acid is the classic flux material that has been used to improve solderability.\nTiffany-type stained glass is made by gluing copper foil around the edges of the pieces of glass and then soldering them together. This method makes it possible to create three-dimensional stained glass pieces.\nElectronics soldering.\nHand soldering.\nFor attachment of electronic components to a PCB, proper selection and use of flux helps prevent oxidation during soldering; it is essential for good wetting and heat transfer. The soldering iron tip must be clean and pre-tinned with solder to ensure rapid heat transfer.\nElectronic joints are usually made between surfaces that have been tinned and rarely require mechanical cleaning, though tarnished component leads and copper traces with a dark layer of oxide passivation (due to aging), as on a new prototyping board that has been on the shelf for about a year or more, may need to be mechanically cleaned.\nTo simplify soldering, beginners are usually advised to apply the soldering iron and the solder separately to the joint, rather than the solder being applied directly to the iron. When sufficient solder is applied, the solder wire is removed. When the surfaces are adequately heated, the solder will flow around the workpieces. The iron is then removed from the joint.\nIf all metal surfaces have not been properly cleaned (\"fluxed\") or brought entirely above the melting temperature of the solder used, the result will be an unreliable (\"cold solder\") joint, even though its appearance may suggest otherwise.\nExcess solder, unconsumed flux and residue is sometimes wiped from the soldering iron tip between joints. The tip of the bit (commonly iron plated to reduce erosion) is kept wetted with solder (\"tinned\") when hot to assist soldering, and to minimize oxidation and corrosion of the tip itself.\nAfter inserting a through-hole mounted component, the excess lead is cut off, leaving a length of about the radius of the pad.\nHand-soldering techniques require a great deal of skill for the fine-pitch soldering of surface-mount chip packages. In particular ball grid array (BGA) devices are notoriously difficult, if not impossible, to rework by hand.\nDefects.\nCold joints.\nVarious problems may arise in the soldering process which lead to joints which are nonfunctional either immediately or after a period of use.\nThe most common defect when hand-soldering results from the parts being joined not exceeding the solder's liquidus temperature, resulting in a \"cold solder\" joint. This is usually the result of the soldering iron being used to heat the solder directly, rather than the parts themselves. Properly done, the iron heats the parts to be connected, which in turn melt the solder, guaranteeing adequate heat in the joined parts for thorough wetting. If using solder wire with an embedded flux core, heating the solder first may cause the flux to evaporate before it cleans the surfaces being soldered.\nA cold-soldered joint may not conduct at all, or may conduct only intermittently. Cold-soldered joints also happen in mass production, and are a common cause of equipment which passes testing, but malfunctions after sometimes years of operation.\nDry joints.\nA \"dry joint\" occurs when the cooling solder is moved. Since non-eutectic solder alloys have a small plastic range, the joint must not be moved until the solder has cooled down through both the liquidus and solidus temperatures. Dry joints often occur because the joint moves when the soldering iron is removed from the joint. They are weak mechanically and poor conductors electrically.\nAvoiding overheating of components.\nFor hand soldering, the heat source tool is selected to provide adequate heat for the size of joint to be completed. A 100-watt soldering iron may provide too much heat for printed circuit boards (PCBs), while a 25-watt iron will not provide enough heat for large electrical connectors.\nUsing a tool with too high a temperature can damage sensitive components, but protracted heating by a tool that is too cool or under powered can also cause heat damage. Excessive heating of a PCB may result in delamination — the copper traces may actually lift off the substrate, particularly on single sided PCBs without through hole plating.\nWhile hand-soldering, a heat sink, such as a crocodile clip, may be used on the leads of heat-sensitive components to reduce heat transfer to the components and avoid damaging them. This is especially applicable to germanium parts.\nThe heat sink limits the temperature of the component body by absorbing and dissipating heat, by reducing the thermal resistance between the component and the air. Meanwhile, the thermal resistance of the leads maintains the temperature difference between the part of the leads being soldered and the component body. Thus, the leads become hot enough to melt the solder while the component body remains cooler. The heat sink will mean the use of more heat to complete the joint, since heat taken up by the heat sink will not heat the work pieces.\nComponents which dissipate large amounts of heat during operation are sometimes elevated above the PCB to avoid PCB overheating. Plastic or metal mounting clips or holders may be used with large devices to aid heat dissipation and reduce joint stresses.\nVisual inspection of joints.\nWhen visually inspected, a good solder joint will appear smooth, bright and shiny, with the outline of the soldered wire clearly visible. In general a good-looking soldered joint is a good joint.\nA matte gray surface is a good indicator of a joint that was moved during soldering. A dry joint has a characteristically dull or grainy appearance immediately after the joint is made. This appearance is caused by crystallization of the liquid solder. Too little solder will result in a dry and unreliable joint.\nCold solder joints are dull and sometimes cracked or pock-marked. If the joint has lumps or balls of otherwise shiny solder, the metal has not wetted properly. Too much solder (the familiar 'solder blob' to beginners) is not necessarily unsound, but tends to mean poor wetting.\nA concave fillet is ideal. The boundary between the solder and the workpiece in a good joint will have a low angle. This indicates good wetting and minimal use of solder, and therefore minimal heating of heat sensitive components. A joint may be good, but if a large amount of unnecessary solder is used, then excess heating was obviously required.\nLead-free solder formulations may cool to a dull surface even if the joint is good. The solder looks shiny while molten, and suddenly hazes over as it solidifies even though it has not been disturbed during cooling.\nFlux use and residue.\nAn improperly selected or applied flux can cause joint failure. Without flux the joint may not be clean, or may be oxidized, resulting in an unsound joint.\nFor electronic work, flux-core solder wire is generally used, but additional flux may be used from a flux pen or dispensed from a small bottle with a syringe-like needle.\nSome fluxes are designed to be stable and inactive when cool and do not need to be cleaned off, though they can if desired. If such fluxes are used, cleaning may merely be a matter of aesthetics or to make visual inspection of joints easier in specialised 'mission critical' applications such as medical devices, military and aerospace. For satellites, this will also reduce weight, slightly but usefully. In high humidity, since even non-corrosive flux might remain slightly active, the flux may be removed to reduce corrosion over time.\nSome fluxes are corrosive and flux residue must be removed after soldering. If not properly cleaned, the flux may corrode the joint or the PCB. Water, alcohol, acetone, or other solvents compatible with the flux and the parts involved are commonly used with cotton swabs or bristle brushes.\nIn some applications, the PCB might also be coated in some form of protective material such as a lacquer to protect it and exposed solder joints from the environment.\nDesoldering and resoldering.\nUsed solder contains some of the dissolved base metals and is unsuitable for reuse in making new joints. Once the solder's capacity for the base metal has been reached, it will no longer properly bond with the base metal, usually resulting in a brittle cold solder joint with a crystalline appearance.\nIt is good practice to remove solder from a joint prior to resoldering — desoldering braids (or wicks) or vacuum desoldering equipment (solder suckers) can be used. Desoldering wicks contain plenty of flux which will remove the oxidation from the copper trace and any device leads that are present. This will leave a bright, shiny, clean junction to be resoldered.\nThe lower melting point of solder means it can be melted away from the base metal, leaving it mostly intact, though the outer layer will be \"tinned\" with solder. Flux will remain which can easily be removed by abrasive or chemical processes. This tinned layer will allow solder to flow onto a new joint, resulting in a new joint, as well as making the new solder flow very quickly and easily.\nWave soldering and reflow soldering.\nCurrently, mass-production printed circuit boards (PCBs) are mostly wave soldered or reflow soldered, though hand soldering of production electronics is also still widely used.\nIn wave soldering, components are prepped (trimmed or modified) and installed on the PCB. Sometimes, to prevent movement they are temporarily kept in place with small dabs of adhesive or secured with a fixture, then the assembly is passed over flowing solder in a bulk container. This solder flow is forced to produce a standing wave so the whole PCB is not submerged in solder, but rather just touched. The result is that solder stays on pins and pads, but not on the PCB itself.\nReflow soldering is a process in which a solder paste (a mixture of prealloyed solder powder and a flux-vehicle that has a peanut butter-like consistency) is used to stick the components to their attachment pads, after which the assembly is heated by an infrared lamp, a hot air pencil, or, more commonly, by passing it through a carefully controlled oven.\nSince different components can be best assembled by different techniques, it is common to use two or more processes for a given PCB. For example, surface mounted parts may be reflow soldered first, with a wave soldering process for the through-hole mounted components coming next, and bulkier parts hand-soldered last.\nHot-bar reflow.\n\"Hot-bar reflow\" is a selective soldering process where two pre-fluxed, solder coated parts are heated with a heating element (called a thermode) to a temperature sufficient to melt the solder.\nPressure is applied through the entire process (usually 15 seconds) to ensure that components stay in place during cooling. The heating element is heated and cooled for each connection. Up to 4000 W can be used in the heating element, allowing fast soldering, good results with connections requiring high energy.\nEnvironmental regulation and RoHS.\nEnvironmental legislation in many countries has led to a change in formulation of both solders and fluxes.\nThe RoHS directives in the European Community required many new electronic circuit boards to be lead-free by 1 July 2006, mostly in the consumer goods industry, but in some others as well. In Japan, lead was phased out prior to legislation by manufacturers, due to the additional expense in recycling products containing lead.\nWater-soluble non-rosin-based fluxes have been increasingly used since the 1980s so that soldered boards can be cleaned with water or water-based cleaners. This eliminates hazardous solvents from the production environment, and from factory effluents.\nEven without the presence of lead, soldering can release fumes that are harmful and/or toxic to humans. It is highly recommended to use a device that can remove the fumes from the work area either by ventilating outside or filtering the air.\nLead-free.\nLead free soldering requires higher soldering temperatures than lead/tin soldering. SnPb 63/37 eutectic solder melts at . SAC lead-free solder melts at .\nNevertheless, many new technical challenges have arisen with this endeavor. To reduce the melting point of tin-based solder alloys, various new alloys have had to be researched, with additives of copper, silver, bismuth as typical minor additives to reduce the melting point and control other properties. Additionally, tin is a more corrosive metal, and can eventually lead to the failure of solder baths.\nLead-free construction has also extended to components, pins, and connectors. Most of these pins used copper frames, and either lead, tin, gold or other finishes. Tin finishes are the most popular of lead-free finishes. Nevertheless, this brings up the issue of how to deal with tin whiskers. The current movement brings the electronics industry back to the problems solved in the 1960s by adding lead. JEDEC has created a classification system to help lead-free electronic manufacturers decide what provisions to take against whiskers, depending upon their application.", "Engineering,_Manufacturing": 0.9999598265, "qwen": "Yes"}
{"id": "1459427", "revid": "18054835", "url": "https://en.wikipedia.org/wiki?curid=1459427", "title": "Non-circular gear", "text": "A non-circular gear (NCG) is a special gear design with special characteristics and purpose. While a regular gear is optimized to transmit torque to another engaged member with minimum noise and wear and with maximum efficiency, a non-circular gear's main objective might be ratio variations, axle displacement oscillations and more. Common applications include textile machines, potentiometers, CVTs (continuously variable transmissions), window shade panel drives, mechanical presses and high torque hydraulic engines.\nA regular gear pair can be represented as two circles rolling together without slip. In the case of non-circular gears, those circles are replaced with anything different from a circle. For this reason NCGs in most cases are not round, but round NCGs looking like regular gears are also possible (small ratio variations result from meshing area modifications).\nGenerally NCG should meet all the requirements of regular gearing, but in some cases, for example variable axle distance, could prove impossible to support and such gears require very tight manufacturing tolerances and assembling problems arise. Because of complicated geometry, NCGs are most likely spur gears and molding or electrical discharge machining technology is used instead of generation.\nMathematical description.\nIgnoring the gear teeth for the moment (i.e. assuming the gear teeth are very small), let formula_1 be the radius of the first gear wheel as a function of angle from the axis of rotation formula_2, and let formula_3 be the radius of the second gear wheel as a function of angle from its axis of rotation formula_4. If the axles remain fixed, the distance between the axles is also fixed:\nAssuming that the point of contact lies on the line connecting the axles, in order for the gears to touch without slipping, the velocity of each wheel must be equal at the point of contact and perpendicular to the line connecting the axles, which implies that:\nEach wheel must be cyclic in its angular coordinates. If the shape of the first wheel is known, the shape of the second can often be found using the above equations. If the relationship between the angles is specified, the shapes of both wheels can often be determined analytically as well.\nIt is more convenient to use the circular variable formula_7 when analyzing this problem. Assuming the radius of the first gear wheel is known as a function of \"z\", and using the relationship formula_8, the above two equations can be combined to yield the differential equation:\nwhere formula_10 and formula_11 describe the rotation of the first and second gears respectively. This equation can be formally solved as:\nwhere formula_13 is a constant of integration.", "Engineering,_Manufacturing": 0.99969244, "qwen": "Yes"}
{"id": "48324135", "revid": "1163919407", "url": "https://en.wikipedia.org/wiki?curid=48324135", "title": "3D metal moulding", "text": "3D metal moulding, also referred to as metal injection moulding or (MIM), is used to manufacture components with complex geometries. The process uses a mixture of metal powders and polymer binders – also known as \"feedstock\" – which are then injection-moulded.\nAfter moulding, the parts are thermally processed in order to remove the binding agent. They are then sintered to a high-density metal component which has mechanical properties comparable to wrought materials.\n3D metal moulding is mainly used to achieve intricate and complex shapes that are very difficult or expensive to produce using conventional manufacturing methods. \nApplications.\n3D metal molding is used in aerospace, medical and other industries. Its popularity is due to its strength in the form of a custom shape or part. More commonly found as a 3D mold are thermoplastic and thermosetting polymers. Both of these processes are used in the following industries:\n3D metal printing.\n3D metal printing builds components by delivering the powdered metal and binder in alternative layers through a nozzle controlled by a computer system, working to a CAD drawing. The initial process does not achieve the required strength so parts must go through a secondary process which involves fusing another type of metal into the shape.\nThere are multiple methods used in 3D metal printing. Selective laser sintering, or SLS, uses heat from a powerful laser to fuse tiny ceramic, glass or plastic particles together, forming a 3D part. Carl Deckard and Joe Beaman of the University of Texas developed and patented the process in the 1980s.\nDirect metal laser sintering, or DMLS, uses a laser to sinter powdered metal into a solid object in gradual layers built upon each other. Cooling channels can be printed to any shape in this process, which lessens time and waste and improves quality.\nSelective laser melting, or SLM, completely melts the powder to form a homogeneous part. This process can only be used for single materials, so is not suitable for alloys.", "Engineering,_Manufacturing": 1.0000059605, "qwen": "Yes"}
{"id": "30548890", "revid": "4460308", "url": "https://en.wikipedia.org/wiki?curid=30548890", "title": "Pentalobular screw thread", "text": "A pentalobular screw thread is a form of self-forming thread used for screws. Self-forming screws are used in ductile materials, such as aluminium and plastics.\nSelf-tapping screws are widely used for driving into sheet metal or plastics and forming their own thread. They may be either self-drilling, forming their own hole through unbroken material, or fitted into a pre-pierced hole. Self-drilling screws have some ability to cut a thread, as for a tap. Others work not by cutting, but rather by roll-forming the thread, pushing excess material out of the way by plastic deformation. This is one reason why ductile host materials, rather than brittle, are needed.\nTo form a close-fitting thread that will not be loose afterwards, roll-forming requires a lobed tool rather than a constant diameter cylindrical tool. This is particularly the case when the tool and the fastener are the same, such as for a screw. A lobed or polygonal form allows residual compressive stresses from the forming parts of the thread to be relieved in the undercut clearance between the lobes.\nThis lobular thread has other advantages too. It allows the screw to be turned with lower torque, which also increases the 'strip-to-drive ratio' between the torques needed to drive the screw in or to damagingly strip the threads out. The proportions of the lobular thread can also change over the length of the screw, so that the tip of the screw can use greater lobulation to form the thread more aggressively and also provide a centring effect.\nIn conjunction with a thread profile with sharp arrises, a three-lobed thread of this form is the basis of the well-known Taptite screws.\nThe optimum number of lobes is five. Their number should be prime, to avoid the usual harmonic effects between lobes. As is already widely recognised with tapered reamers, five has better stability than three in imperfectly circular holes. More lobes than this, such as seven, would reduce the spacing for clearance between the lobes. A patent has been applied for about a thread with such an optimised pentalobular form.\nSuch thread forms are not a new innovation. A patent for machinery to roll-form the threads of the screws was granted in 1975.", "Engineering,_Manufacturing": 0.9999525547, "qwen": "Yes"}
{"id": "30578054", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=30578054", "title": "Operation chart", "text": "The operation chart is a graphical and symbolic representation of the manufacturing operations used to produce a product. The operation chart illustrates only the value-adding activities in the manufacturing process; therefore, material handling and storage are not illustrated in this chart. operation chart records the overall picture of process and sequencewise steps of operations.\nOperations and their symbols in the operation chart.\nThe operations described in the operation chart are:", "Engineering,_Manufacturing": 0.9999833107, "qwen": "Yes"}
{"id": "42966106", "revid": "575347", "url": "https://en.wikipedia.org/wiki?curid=42966106", "title": "Instrumentation and control engineering", "text": "Instrumentation and control engineering (ICE) is a branch of engineering that studies the measurement and control of process variables, and the design and implementation of systems that incorporate them. Process variables include pressure, temperature, humidity, flow, pH, force and speed. \nICE combines two branches of engineering. Instrumentation engineering is the science of the measurement and control of process variables within a production or manufacturing area. Meanwhile, control engineering, also called control systems engineering, is the engineering discipline that applies control theory to design systems with desired behaviors. \nControl engineers are responsible for the research, design, and development of control devices and systems, typically in manufacturing facilities and process plants. Control methods employ sensors to measure the output variable of the device and provide feedback to the controller so that it can make corrections toward desired performance. Automatic control manages a device without the need of human inputs for correction, such as cruise control for regulating a car's speed. \nControl systems engineering activities are multi-disciplinary in nature. They focus on the implementation of control systems, mainly derived by mathematical modeling. Because instrumentation and control play a significant role in gathering information from a system and changing its parameters, they are a key part of control loops.\nAs profession.\nHigh demand for engineering professionals is found in fields associated with process automation. Specializations include industrial instrumentation, system dynamics, process control, and control systems. Additionally, technological knowledge, particularly in computer systems, is essential to the job of an instrumentation and control engineer; important technology-related topics include human–computer interaction, programmable logic controllers, and SCADA. The tasks center around designing, developing, maintaining and managing control systems.\nThe goals of the work of an instrumentation and control engineer are to maximize:\nAs academic discipline.\nMany universities teach instrumentation and control engineering as an academic courses at the graduate and postgraduate levels. It is possible to approach this field coming from many standard engineering backgrounds, being the most common among them Electrical and Mechanical Engineering, since these branches cover strong foundational subjects in control systems, system dynamics, electro-mechanical machines and devices, as well as electric circuits. ", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "3095430", "revid": "44110902", "url": "https://en.wikipedia.org/wiki?curid=3095430", "title": "Association for Manufacturing Technology", "text": "The Association for Manufacturing Technology (AMT) is a trade association based in McLean, Virginia, in the United States. It was founded as the National Machine Tool Builders' Association (NMTBA) in 1902. It represents and promotes the interests of American providers of manufacturing machinery and equipment.\nAs machine tools advanced, NMTBA launched the first National Machine Tool Builders’ Exposition in 1927, which would later be rebranded IMTS- International Manufacturing Technology Show.\nThe AMT’s most visible activity is its management of the International Manufacturing Technology Show (IMTS), which is held on even-numbered years at McCormick Place in Chicago, Illinois.\nExamples of activities fostered by the AMT include:\nAMT also supports their membership with technology centers and representative offices in China, India, Poland, Mexico and Brazil.\nOther AMT Events.\nAMT puts on a number of events throughout the year. While IMTS takes place in every even year, AMT also hosts the MFG Meeting and MTForecast Conference every year. ", "Engineering,_Manufacturing": 0.9999997616, "qwen": "Yes"}
{"id": "6881317", "revid": "7852030", "url": "https://en.wikipedia.org/wiki?curid=6881317", "title": "Spur gear", "text": "Spur gears or straight-cut gears are the simplest type of gear. They consist of a cylinder or disk with teeth projecting radially. Viewing the gear at 90 degrees from the shaft length (side on) the tooth faces are straight and aligned parallel to the axis of rotation. Looking down the length of the shaft, a tooth's cross section is usually not triangular. Instead of being straight (as in a triangle) the sides of the cross section have a curved form (usually involute and less commonly cycloidal) to achieve a constant drive ratio. Spur gears mesh together correctly only if fitted to parallel shafts. No axial thrust is created by the tooth loads. Spur gears are excellent at moderate speeds but tend to be noisy at high speeds.\nSpur gear can be classified into two pressure angles, 20° being the current industry standard and 14½° being the former (often found in older equipment). Spur gear teeth are manufactured as either involute profile or cycloidal profile. When two gears are in mesh it is possible that an involute portion of one will contact a non-involute portion of the other gear. This phenomenon is known as \"interference\" and occurs when the number of teeth on the smaller of the two meshing gears is less than a required minimum. Undercutting (cutting the tooth narrower closer to its base) is sometimes used to avoid interference but is usually not suitable because the decreased thickness leaves the tooth weaker at its base. In this situation, corrected gears are used. In corrected gears the cutter rack is shifted upwards or downwards.\nSpur gears can be classified into two main categories: External and Internal. Gears with teeth on the outside of the cylinder are known as \"external gears\". Gears with teeth on the internal side of the cylinder are known as \"internal gears\". An external gear can mesh with an external gear or an internal gear. When two external gears mesh together they rotate in the opposite directions. An internal gear can only mesh with an external gear and the gears rotate in the same direction. Due to the close positioning of shafts, internal gear assemblies are more compact than external gear assemblies.\nPCD and MOD.\nIn the case of Module (MOD) 4.0 spur gears:\nThere are two types of corrected gears:", "Engineering,_Manufacturing": 0.9999493361, "qwen": "Yes"}
{"id": "42928971", "revid": "16490385", "url": "https://en.wikipedia.org/wiki?curid=42928971", "title": "Airwolf 3D", "text": "Airwolf 3D is a Costa Mesa, California-based company that produces 3D printers.\nHistory.\nAirwolf was founded in May 2012 by Erick Wolf, a garage mechanic and patent attorney with a mechanical engineering degree, and his wife Eva. The inspiration for the company came from a 3D printer that Erick bought just before Christmas 2011. After encountering difficulty with his goal of getting the printer to print replacement parts for itself, he spent several days working on the printer before determining that it wasn't able to complete the task. The printer was eventually scrapped for parts, and Erick instead began building his own printer, which was named the Airwolf 3D.\nThe original Airwolf printer (v.4) was derived from the Prusa Mendel and Mecano Air designs, hence the name \"Airwolf.\"\nThe company started shipping fully assembled 3D printers in June 2012 from their garage in Newport Beach, California. The first printer was sold to Lars Brubaker and Kevin Pope of MatterHackers. MatterHackers went on to develop MatterControl, 3D printing software that works with many 3D printers and is offered in a customized version for Airwolf 3D.\nAirwolf's customer base includes Boeing, John Deere, Raytheon, Saleen Automotive and Honeywell — as well as schools and home hobbyists.\nProducts.\nAW3D 5.5.\nThe AW3D 5.5 was introduced in late 2012 and superseded the v.4 and v.5.\nAW3D XL.\nThe AW3D XL was introduced in January 2013. The maximum printing surface is approximately 12\"x 8\"x 7\". It operates on a RAMBo board made by Ultimachine which offers options for expandability, such as a dual extruder, multiple fans, and several other features including direct heatbed control. The XL 3D printer plays an integral part in “STEAM” academic curricula in Orange Unified School District.\nAW3D HD.\nThe AW3D HD was introduced in November 2013 at the 3D Print Show in Paris, France. It featured a print area of approximately 12\"x8\"x12.\" The AW3D HD featured a print volume of 12\" x 8\" x 12\" (1150in³) and had a layer-to-layer resolution of .06mm (.002\"). The HD was equipped with a single print head that came standard with a .5mm nozzle or a .35mm nozzle as an option.\nAW3D HDL.\nThe AW3D HDL was the Airwolf 3D base model 3D printer which could be upgraded depending on the user's needs. It was equipped with an un-heated print bed and a single print head capable of sustained temperatures of 260°C (500°F). The AW3D had a print resolution of .08mm with a maximum print speed of 150mm/s. The AW3D had a build volume of 12\" x 8\" x 11\" (1056in³) and came standard with .5mm print nozzle or a .35mm nozzle optional.\nAW3D HDx.\nThe AW3D HDx was introduced in May 2014. It is a 3D printer can build prototypes out of engineering-grade materials like polycarbonate, bridge nylon and nylon 645. The HDx uses the company's JRx hot end and can continuously hold temperatures of up to 599°F, which allows 3D printing in more durable materials. The HDx was selected as Editor's Pick of the Week by Desktop Engineering. The HDX had a print volume of 12\" x 8\" x 12\" (1150in³) and had a layer-to-layer resolution of .06mm (.002\"). The HDX came was equipped with the proprietary JRx high-temperature print head and came standard with a .5mm nozzle or an optional .35mm nozzle.\nAW3D HD2x.\nThe AW3D HD2x was a dual-head 3D printer that was introduced in 2014. The HD2x featured a dual print head capable of sustained temperatures of 315 °C(599 °F). The original HD2x was designed for traditional hard-wired printing and slicing functionality; however, wireless capability was later provided by Airwolf 3D's Wolfbox™ wireless controller. The HD2x was capable of printing in two different colors or two different materials simultaneously provided that the two materials had similar extruding temperatures. The HD2x had a print volume of 11\" X 8\" x 12\" (1056in³) and offered a layer-to-layer resolution as fine as .06mm (.002\").\nAW3D HD-R.\nThe AW3D HD-R was introduced at the 2015 Consumer Electronics Show. The HD-R was the first Airwolf 3D model to offer integrated WiFi and cloud based slicing, file storage, and file management based on the AstroPrint® platform by 3DaGoGo®. The HD-R could be interfaced via a traditional PC connection or a mobile device. By default an 8” tablet was supplied with the each unit for wireless interface. The HD-R came equipped with dual print heads each capable of sustained temperatures of 315°C (599°F). The dual print head configuration allowed the user to print with two different colors or two different types of filament provided that the filaments had similar extruding temperatures. The HD-R was built with an improved aluminum backbone for rigidity and had a maximum build envelope of 11”x 8”x 12” (1056 in³). The HD-R had a print resolution of .06mm (.002\") and came standard with a .5mm nozzle or an optional .35mm nozzle.\nAXIOM.\nThe first in the AXIOM line is made from extruded aluminum and injection molded polycarbonate parts. It has a large build volume of 12.5”x8”x10”, can print layers as fine as 40 microns, and its heated bed, along with the company's proprietary hot end, allow the AXIOM to print in a wide variety of materials, from PLA to Nylon and polycarbonate. And, with the integration of cloud printer management system AstroPrint, the AXIOM can be controlled via the web, as well as USB, micro SD card, or Ethernet.\nWolfbite.\nWolfbite is a 3D printing adhesive to facilitate the bonding and removal of nylon and nylon blend prints from glass and ceramic build plates. The product was formulated to solve the problems of warping and adhesion that are inherent when 3D printing with nylon.\nSpecifications.\nMany components are fabricated using acrylonitrile butadiene styrene (ABS), a common thermoplastic.", "Engineering,_Manufacturing": 0.9997515082, "qwen": "Yes"}
{"id": "47185788", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=47185788", "title": "Uttara Export Processing Zone", "text": "Uttara Export Processing Zone (UEPZ) , also known as Uttara EPZ or Nilphamari EPZ, is the seventh of the eight export processing zone in Bangladesh located at Nilphamari. It's the only export processing zone of Rangpur division/ north Bengal. It was established in September 2001on about 213,66 acres of lands in Sangloshi area in Nilphamari town.\nIndustrial plot.\nThere are more than 180 industrial plots in this EPZ. Allocation of 138 plots has been completed. 12 plots are running. 33 plots undeveloped and 09 plots are empty.\nCompany.\n1. Evergreen Products Factory (BD) Ltd. \n2. Ventura Leatherware MFY (BD) Ltd. \n3. Sonic (Bangladesh) Ltd. \n4. Mazen (Bangladesh) Industries Ltd. \n5. Kord (BD) Ltd 6. Dong Jin Industrial (BD) Company Ltd. \n7. EPF Printing Ltd \n8. Oasis Transformation Ltd. \n9. EPF Cartoon Ltd. \n10. DESHBANDHU TEXTILES MILLS LTD \n11. EXPO LINK IND. LTD \n12. NILPHAMARI PACKAGING LTD \n13. Section Seven International Limited \n14. Uttara Sweater Manufacturing Company Limited \n15. Viyellatex Apparels Ltd. \n16. Independent Export (BD) Ltd. \n17. Glorious Export BD Ltd. \n18. SKY Star IND. LTD. \n19. Fardin Accessories Limited \n20. Quest Accessories (BD) Ltd. \n21. TN Accessories Ltd.\n22. Padma Spining & Composite", "Engineering,_Manufacturing": 0.9998943806, "qwen": "Yes"}
{"id": "10948234", "revid": "57939", "url": "https://en.wikipedia.org/wiki?curid=10948234", "title": "Microthermoforming", "text": "Microthermoforming is the abbreviation for microscopic or microscale thermoforming, or, more precisely, for thermoforming of microproducts or microstructure products. Microstructure products means products that have structures in the micrometre range and have their technical function provided by the shape of the microstructure [1]. Thermoforming [2] in turn means shaping of heated and therefore softened semi finished products in the form of thermoplastic polymer films or plates with their edges fixed by three-dimensional stretching. Shaping is carried out mainly by forming the films or plates into female moulds (negative forming) or over male moulds (positive forming). While the other polymer microreplication processes such as micro injection moulding or (vacuum) hot embossing are primary forming processes where forming occurs already in a molten, liquid phase of the heated polymer material, microthermoforming is a secondary forming process where forming occurs in a strongly softened, but still solid phase of the heated polymer.\nMoulds for polymer microreplication in general and in particular for microthermoforming can be fabricated by various methods such as mechanical micromachining, lithographic based methods in combination with electroplating (see also the so-called 'LIGA' process) and wet or dry etching. And they can be fabricated of various materials such as metal, silicon and glass.\nState of the art.\nFor several years now, at Karlsruhe Institute of Technology (KIT), a pressure or high pressure (thermo)forming process is used to fabricate film microchips for capillary electrophoresis (CE) [3–5] and for three-dimensional cell cultivation [6–8]. The process is derived from the macroscopic trapped sheet forming process [2]. This is a simple variation of vacuum or pressure forming without prestretching, i.e. a single stage forming, into a female mould with heating of the plastic sheet using a contact heating plate inside the forming station. The forming air is supplied via through holes in the heating plate. Still in a laboratory scale process, diverse thermoplastic films also from biodegradable polymers such as polycaprolactone (PCL) with thicknesses typically between 20 and 100 μm are thermoformed. This is performed with gas pressures up to 5 MPa into mechanically micromachined cavities of plate shaped micromoulds from brass.\nFirst examples of processes coming near to something that could be called 'microthermoforming' originate from the second half of the nineties. So, in 1993, dome shaped polymer microstructures for use in electrical membrane switches were fabricated [9]. This was done between a mating upper and lower metal emboss die with a concave and a convex detail, respectively, first in a hot, then in a second cold press. And in 1999, corrugated sheet like polymer microstructures for use e.g. in electrostatic actuators were fabricated [10]. This was also done between heated tools and counter tools, namely in discontinuous processes between stamps or in continuous processes between rollers. Partly, the counter tool was a soft one in the form of a thicker, unpatterned film or plate made from an easily deformable, e.g. elastomeric material which is able to assume the shape of the hard, metallic tool. In 2006, at the School of Polymer, Textile and Fiber Engineering (PTFE) of the Georgia Institute of Technology (GIT), the same technology approach was used to fabricate similar corrugated sheet like structures in a so-called 'rubber-assisted hot embossing process' [11].\nFeatures and applications.\nThe microthermoforming process including its products can have all the advantageous properties of the powerful macroscopic production process. Moreover, the thermoformed microparts have additional, specific properties appearing only in microscale dimensions and resulting from their unusual morphology. Thermoformed e.g. microfluidic structures have free standing microcavities such as channels and reservoirs and they are thin walled partly in the range of a few micrometers. Specific properties of thermoformed microparts are, amongst others, their high flexibility, their small volume and mass, their low thermal resistance and heat capacity, and their low light absorbance and background fluorescence. Morphology and properties of these microparts now can result in improved or even new, so far unthought of applications.\nCompared to the other microreplication processes, in microthermoforming, modifications of the film to be formed remain preserved beyond the forming step due to the already mentioned material coherence during this secondary forming process. This enables surface and bulk modification and functionalisation of the three-dimensionally formed films or membranes, namely as highly resolved micro- and nanopatterns, and all side, i.e. on hardly accessible side walls and even behind undercuts. Thus, e.g. thermoformed chips for three-dimensional cell cultivation can be provided with pores, cell adhesion patterns [6–8], surface topologies and electrodes [12].\nFuture application fields for microthermoforming are expected to be", "Engineering,_Manufacturing": 0.9999932051, "qwen": "Yes"}
{"id": "9318647", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=9318647", "title": "Electron-beam additive manufacturing", "text": "Electron-beam additive manufacturing, or electron-beam melting (EBM) is a type of additive manufacturing, or 3D printing, for metal parts. The raw material (metal powder or wire) is placed under a vacuum and fused together from heating by an electron beam. This technique is distinct from selective laser sintering as the raw material fuses having completely melted.\nMetal powder-based systems.\nMetal powders can be consolidated into a solid mass using an electron beam as the heat source. Parts are manufactured by melting metal powder, layer by layer, with an electron beam in a high vacuum.\nThis powder bed method produces fully dense metal parts directly from metal powder with characteristics of the target material. The EBM machine reads data from a 3D CAD model and lays down successive layers of powdered material. These layers are melted together utilizing a computer-controlled electron beam. In this way it builds up the parts. The process takes place under vacuum, which makes it suited to manufacture parts in reactive materials with a high affinity for oxygen, e.g. titanium. The process is known to operate at higher temperatures (up to 1000 °C), which can lead to differences in phase formation though solidification and solid-state phase transformation.\nThe powder feedstock is typically pre-alloyed, as opposed to a mixture. That aspect allows classification of EBM with selective laser melting (SLM), where competing technologies like SLS and DMLS require thermal treatment after fabrication. Compared to SLM and DMLS, EBM has a generally superior build rate because of its higher energy density and scanning method.\nResearch developments.\nRecent work has been published by ORNL, demonstrating the use of EBM technology to control local crystallographic grain orientations in Inconel. After testing in the transmission electron microscope by the state-of-the-art in-situ technique, the EBM Inconel alloy has been proved to exhibit similar mechanical property comparing to a wrought Inconel alloy. Other notable developments have focused on the development of process parameters to produce parts out of alloys such as copper, niobium, Al 2024, bulk metallic glass, stainless steel, and titanium aluminide. Currently commercial materials for EBM include commercially pure Titanium, Ti-6Al-4V, CoCr, Inconel 718, and Inconel 625.\nMetal wire-based systems.\nAnother approach is to use an electron beam to melt welding wire onto a surface to build up a part. This is similar to the common 3D printing process of fused deposition modeling, but with metal, rather than plastics. With this process, an electron-beam gun provides the energy source used for melting metallic feedstock, which is typically wire. The electron beam is a highly efficient power source that can be both precisely focused and deflected using electromagnetic coils at rates well into thousands of hertz. Typical electron-beam welding systems have high power availability, with 30- and 42-kilowatt systems being most common. A major advantage of using metallic components with electron beams is that the process is conducted within a high-vacuum environment of 1 Torr or greater, providing a contamination-free work zone that does not require the use of additional inert gases commonly used with laser and arc-based processes. With EBDM, the feedstock material is fed into a molten pool created by the electron beam. Through the use of computer numeric controls (CNC), the molten pool is moved about on a substrate plate, adding material just where it is needed to produce the near net shape. This process is repeated in a layer-by-layer fashion until the desired 3D shape is produced.\nDepending on the part being manufactured, deposition rates can range up to per hour. With a light alloy, such as titanium, this translates to a real-time deposition rate of per hour. A wide range of engineering alloys are compatible with the EBDM process and are readily available in the form of welding wire from an existing supply base. These include, but are not limited to, stainless steels, cobalt alloys, nickel alloys, copper nickel alloys, tantalum, titanium alloys, as well as many other high-value materials.\nMarket.\nTitanium alloys are widely used with this technology, which makes it a suitable choice for the medical implant market.\nCE-certified acetabular cups are in series production with EBM since 2007 by two European orthopedic implant manufacturers, Adler Ortho and Lima Corporate.\nThe U.S. implant manufacturer Exactech has also received FDA clearance for an acetabular cup manufactured with the EBM technology. \nAerospace and other highly demanding mechanical applications are also targeted, see Rutherford rocket engine.\nThe EBM process has been developed for manufacturing parts in gamma titanium aluminide and is currently being developed by Avio S.p.A. and General Electric Aviation for the production of turbine blades in γ-TiAl for gas-turbine engines.\nThe first EBM machine in the United States is housed by the Department of Industrial and Systems Engineering at North Carolina State University. ", "Engineering,_Manufacturing": 1.0000059605, "qwen": "Yes"}
{"id": "2186444", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=2186444", "title": "Laser-hybrid welding", "text": "Laser-hybrid welding is a type of welding process that combines the principles of laser beam welding and arc welding.\nThe combination of laser light and an electrical arc into an amalgamated welding process has existed since the 1970s, but has only recently been used in industrial applications. There are three main types of hybrid welding process, depending on the arc used: TIG, plasma arc or MIG augmented laser welding. While TIG-augmented laser welding was the first to be researched, MIG is the first to go into industry and is commonly known as hybrid laser welding.\nWhereas in the early days laser sources still had to prove their suitability for industrial use, today they are standard equipment in many manufacturing enterprises.\nThe combination of laser welding with another weld process is called a \"hybrid welding process\". This means that a laser beam and an electrical arc act simultaneously in one welding zone, influencing and supporting each other.\nLaser.\nLaser welding not only requires high laser power but also a high quality beam to obtain the desired \"deep-weld effect\". The resulting higher quality of beam can be exploited either to obtain a smaller focus diameter or a larger focal distance. A variety of laser types are used for this process, in particular where the laser light can be transmitted via a water-cooled glass fiber. The beam is projected onto the workpiece by collimating and focusing optics. Carbon dioxide laser can also be used where the beam is transmitted via lens or mirrors.\nLaser-hybrid process.\nFor welding metallic objects, the laser beam is focused to obtain intensities of more than 1 MW/cm2. When the laser beam hits the surface of the material, this spot is heated up to vaporization temperature, and a vapor cavity is formed in the weld metal due to the escaping metal vapor. This is known as a keyhole. The extraordinary feature of the weld seam is its high depth-to-width ratio. The energy-flow density of the freely burning arc is slightly more than 100 kW/cm2. Unlike a dual process where two separate weld processes act in succession, hybrid welding may be viewed as a combination of both weld processes acting simultaneously in one and the same process zone. Depending on the kind of arc or laser process used, and depending on the process parameters, the two systems will influence each other in different ways.\nThe combination of the laser process and the arc process results in an increase in both weld penetration depth and welding speed (as compared to each process alone). The metal vapor escaping from the vapor cavity acts upon the arc plasma. Absorption of the laser radiation in the processing plasma remains negligible. Depending on the ratio of the two power inputs, the character of the overall process may be mainly determined either by the laser or by the arc.\nAbsorption of the laser radiation is substantially influenced by the temperature of the workpiece surface. Before the laser welding process can start, the initial reflectance must be overcome, especially on aluminum surfaces. This can be achieved by preheating the material. In the hybrid process, the arc heats the metal, helping the laser beam to couple in. After the vaporisation temperature has been reached, the vapor cavity is formed, and nearly all radiation energy can be put into the workpiece. The energy required for this is thus determined by the temperature-dependent absorption and by the amount of energy lost by conduction into the rest of the workpiece. In laser-hybrid welding, using MIG, vaporisation takes place not only from the surface of the workpiece but also from the filler wire, so that more metal vapor is available to facilitate the absorption of the laser radiation.\nFatigue behavior.\nOver the years a great deal of research has been done to understand fatigue behavior, particularly for new techniques like laser-hybrid welding, but knowledge is still limited. Laser-hybrid welding is an advanced welding technology that creates narrow deep welds and offers greater freedom to control the weld surface geometry. Therefore, fatigue analysis and life prediction of hybrid weld joints has become more important and is the subject of ongoing research.", "Engineering,_Manufacturing": 1.000007987, "qwen": "Yes"}
{"id": "2190195", "revid": "42522270", "url": "https://en.wikipedia.org/wiki?curid=2190195", "title": "Changeover", "text": " \nIn manufacturing, changeover is the process of converting a line or machine from running one product to another. Changeover times can last from a few minutes to as much as several weeks in the case of automobile manufacturers retooling for new models. Reducing changeover times became a popular way to reduce waste in Lean manufacturing after Taiichi Ohno and Shingo Shigeo popularized the SMED (Single Minute Die Exchange) method in the, now famous, Toyota Production System (TPS). The terms \"set-up\" and \"changeover\" are sometimes used interchangeably however this usage is incorrect. Set-up is only one component of changeover. Example: A soft drink bottler may run 16oz glass bottles one day, perform a changeover on the line and then run 20oz plastic bottles the next day.\nThe 3 Ups.\nChangeover can be divided into the 3 Ups:\nClean-up.\n\"Clean-up product, materials and components from the line. It may range from minor, if only the label of a package is being changed (for example from an English to a Spanish label) to major, requiring complete disassembly of the equipment, cleaning and sterilizing of the line components in the case of an injectable pharmaceutical product.\nSet-up.\n\"Set-up\" is the process of actually converting the equipment. This may be achieved by adjusting the equipment to correspond to the next product or by changing non-adjustable \"change parts\" to accommodate the product. Typically it will be a combination of both.\nStart-up.\n\"Start-up\" is the time spent fine tuning the equipment after it has been restarted. It is characterized by frequent stoppages, jams, quality rejects and other problems. It is generally caused by variability in the clean-up and set-up or by variability in the product or its components.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "33476252", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=33476252", "title": "Sherlock Automated Design Analysis", "text": "Sherlock Automated Design Analysis is a software tool developed by DfR Solutions for analyzing, grading, and certifying the expected reliability of products at the circuit card assembly level. Based on the science of Physics of Failure, Sherlock predicts failure mechanism-specific failure rates over time using a combination of finite element method and material properties to capture stress values and first order analytical equations to evaluate damage evolution. The software is designed for use by design and reliability engineers and managers in the electronics industry. DfR Solutions is based in Beltsville, Maryland, USA, and was acquired by ANSYS, Inc. in May 2019.\nApproach.\nUsers upload either a complete design package, like ODB++ or IPC-2581, or individual data packets, such as Gerber, Bill of Materials, and Pick and Place files.\nSherlock incorporates stresses from a variety of environments into its physics-based prediction algorithms, including elevated temperature, thermal cycling, vibrations (random and harmonic), mechanical shock and electrical stresses (voltage, current, power). Sherlock then performs several different types of reliability analysis and provides the useful (constant failure rate) and wear out (increasing failure rate) portions of the life curve for each mechanism-component combination. The specific mechanisms that are evaluated and predicted include low-cycle solder fatigue due to thermal cycling, high-cycle solder fatigue due to vibration, solder cracking/component cracking/pad cratering due to mechanical shock or excessive flexure, lead fatigue, wire bond fatigue, via fatigue, electromigration, time dependent dielectric breakdown, hot-carrier injection, and negative bias temperature instability. Published research has indicated that the physics of failure-based predictions are highly accurate and are now used to validate other techniques.\nThese individual life curves are then summed to provide a physics-based reliability curve for the overall product. Sherlock also provides design rule checks (DRC) for board-level design (schematic and layout) and an overall reliability score. The reliability scoring, which is provided for the overall products – as well as individual scores and commentary for each area of analysis is used when physics-based quantitative predictions are not possible. The analysis is delivered both in PDF and HTML format. Depending on the types of analysis run and the data entered to create the analysis, reports can run between 20 and over 200 pages in length.\nThe semiconductor module is in compliance with SAE ARP 6338 and is being considered as a replacement to traditional empirical reliability prediction methods (MIL-HDBK-217, Telcordia SR-332, FIDES, and Siemens SN29500) in predicting the reliability of semiconductor devices.\nA graphical interface allows users to examine results, make iterations, and pre-perform analyses as necessary. The software does not allow the user to make permanent changes to the electronic design. This activity takes place within the original EDA or CAD software. Sherlock is compatible with Abaqus, Ansys, and Siemens NX.\nOutputs.\nSherlock Automated Design Analysis produces the following outputs:\nVersion History.\nSherlock Automated Design Analysis was launched in April 2011. Subsequent releases include\nMarket Acceptance.\nA company has reported requiring suppliers use Sherlock to reduce risk and help accelerate design validation and product verification.", "Engineering,_Manufacturing": 0.9998775721, "qwen": "Yes"}
{"id": "25276638", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=25276638", "title": "Ball transfer unit", "text": "Ball transfer units are omnidirectional load-bearing spherical balls mounted inside a restraining fixture. They are identical in principle to a computer trackball (pointing device). Typically the design involves a single large ball supported by smaller ball bearings. \nThey are commonly used in an inverted ball up position where objects are quickly moved across an array of units, known as a ball transfer table, a type of conveyor system. This permits manual transfer to and from machines and between different sections of another conveyor system. They are used in airports for luggage delivery, or in industry as part of manufacturing systems. Prior to the invention of the ball transfer unit, first patented by Autoset Production Ltd in 1958, these applications were solved by the use of inverted casters. However, casters recognise a trail, meaning that the wheels had to align before directional change could be achieved.\nBall transfer units can also be used in a non-inverted ball down position as a type of caster, however this use is restricted by load-bearing limitations and the type of floor. Manufacturers have addressed this problem with ball transfer units incorporating recirculating ball principles, however the inverted position is still the most common application and the least problematic.", "Engineering,_Manufacturing": 1.0000023842, "qwen": "Yes"}
{"id": "37434918", "revid": "15420072", "url": "https://en.wikipedia.org/wiki?curid=37434918", "title": "Toyota Motors Tohoku", "text": "Toyota Motors Tohoku was an auto parts manufacturing subcontractor under the Toyota Group. The company was created in July 1997 in Taiwa, Miyagi, Japan.\nOn July 1, 2012, three Toyota subcontractors Central Motors, Toyota Motors Tohoku, and Kanto Auto Works assumed operations as a combined company, with all manufacturing facilities and assets of the three former companies to now be known as Toyota Motor East Japan, Inc.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "37440954", "revid": "13467261", "url": "https://en.wikipedia.org/wiki?curid=37440954", "title": "Wetting current", "text": "In electrical and electronics engineering, wetting current is the minimum electric current needing to flow through a contact to break through the surface film resistance at a contact. It is typically far below the contact's nominal maximum current rating.\nA thin film of oxidation, or an otherwise passivated layer, tends to form in most environments, particularly those with high humidity, and, along with surface roughness, contributes to the contact resistance at an interface. Providing a sufficient amount of wetting current is a crucial step in designing systems that use delicate switches with small contact pressure as sensor inputs. Failing to do this might result in switches remaining electrically \"open\" when pressed, due to contact oxidation.\nCapacitor discharge solution.\nIn some low voltage applications, where switching current is below the manufacturer's wetting current specification, a capacitor discharge method may be employed by placing a small capacitor across the switch contacts to boost the current through contact surface upon contact closure.\nSealing current.\nA related term sealing current (aka wetting current or fritting current) is widely used in the telecommunication industry describing a small constant DC current (typically 1-20 mA) in copper wire loops in order to avoid contact oxidation of contacts and splices. It is defined in ITU-T G.992.3 for \"all digital mode ADSL\" as a current flowing from the ATU-C (ADSL Linecard) via the phone lines to the ATU-R (CPE). Carbon brushes develop high resistance glaze when they're used without current flow for an extended period. A special circuit is utilized for turbines and generators to introduce current through the brushes into the shaft to prevent this contact fritting.\nContact cleaner.\nContact cleaner can be applied to the contact surfaces to inhibit the formation of resistive surface films and/or to ameliorate existing films.", "Engineering,_Manufacturing": 1.0000065565, "qwen": "Yes"}
{"id": "1850694", "revid": "42362362", "url": "https://en.wikipedia.org/wiki?curid=1850694", "title": "Drawing (manufacturing)", "text": "Drawing is a metalworking process that uses tensile forces to elongate metal, glass, or plastic. As the material is drawn (pulled), it stretches and becomes thinner, achieving a desired shape and thickness. Drawing is classified into two types: sheet metal drawing and wire, bar, and tube drawing. Sheet metal drawing is defined as a plastic deformation over a curved axis. For wire, bar, and tube drawing, the starting stock is drawn through a die to reduce its diameter and increase its length. Drawing is usually performed at room temperature, thus classified as a cold working process; however, drawing may also be performed at higher temperatures to hot work large wires, rods, or hollow tubes in order to reduce forces. \nDrawing differs from rolling in that pressure is not applied by the turning action of a mill but instead depends on force applied locally near the area of compression. This means the maximal drawing force is limited by the tensile strength of the material, a fact particularly evident when drawing thin wires.\nThe starting point of cold drawing is hot-rolled stock of a suitable size.\nMetal.\nSuccessful drawing depends on the flow and stretch of the material. Steels, copper alloys, and aluminium alloys are commonly drawn metals.\nIn sheet metal drawing, as a die forms a shape from a flat sheet of metal (the \"blank\"), the material is forced to move and conform to the die. The flow of material is controlled through pressure applied to the blank and lubrication applied to the die or the blank. If the form moves too easily, wrinkles will occur in the part. To correct this, more pressure or less lubrication is applied to the blank to limit the flow of material and cause the material to stretch or set thin. If too much pressure is applied, the part will become too thin and break. Drawing metal requires finding the correct balance between wrinkles and breaking to achieve a successful part.\nSheet metal drawing becomes deep drawing when the workpiece is longer than its diameter. It is common that the workpiece is also processed using other forming processes, such as piercing, ironing, necking, rolling, and beading. In shallow drawing, the depth of drawing is less than the smallest dimension of the hole.\nBar, tube, and wire drawing all work upon the same principle: the starting stock is drawn through a die to reduce its diameter and increase its length. Usually, the die is mounted on a draw bench. The starting end of the workpiece is narrowed or pointed to get the end through the die. The end is then placed in grips which pull the rest of the workpiece through the die.\nDrawing can also be used to cold form a shaped cross-section. Cold drawn cross-sections are more precise and have a better surface finish than hot extruded parts. Inexpensive materials can be used instead of expensive alloys for strength requirements, due to work hardening. Bars or rods that are drawn cannot be coiled; therefore, straight-pull draw benches are used. Chain drives are used to draw workpieces up to . Hydraulic cylinders are used for shorter length workpieces. The reduction in area is usually restricted to between 20% and 50%, because greater reductions would exceed the tensile strength of the material, depending on its ductility. To achieve a certain size or shape, multiple passes through progressively smaller dies and intermediate anneals may be required. Tube drawing is very similar to bar drawing, except the beginning stock is a tube. It is used to decrease the diameter, improve surface finish, and improve dimensional accuracy. A mandrel may or may not be used depending on the specific process used. A floating plug may also be inserted into the inside diameter of the tube to control the wall thickness. Wire drawing has long been used to produce flexible metal wire by drawing the material through a series of dies of decreasing size. These dies are manufactured from a number of materials, the most common being tungsten carbide and diamond.\nThe cold drawing process for steel bars and wire is as follows:\nGlass.\nSimilar drawing processes are applied in glassblowing and in making glass and plastic optical fiber.\nPlastics.\nPlastic drawing, sometimes referred to as \"cold drawing\", is the same process as used on metal bars, applied to plastics. Plastic drawing is primarily used in manufacturing plastic fibers. The process was discovered by Julian W. Hill in 1930 while trying to make fibers from an early polyester.\nIt is performed after the material has been \"spun\" into filaments; by extruding the polymer melt through pores of a spinneret. During this process, the individual polymer chains tend to somewhat align because of viscous flow. These filaments still have an amorphous structure, so they are drawn to align the fibers further, thus increasing crystallinity, tensile strength, and stiffness. This is done on a draw twister machine. For nylon, the fiber is stretched to four times its spun length. The crystals formed during drawing are held together by hydrogen bonds between the amide hydrogens of one chain and the carbonyl oxygens of another chain. Polyethylene terephthalate (PET) sheet is drawn in two dimensions to make BoPET (biaxially-oriented polyethylene terephthalate) with improved mechanical properties.", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "1850771", "revid": "57939", "url": "https://en.wikipedia.org/wiki?curid=1850771", "title": "Modified atmosphere", "text": "Modified atmosphere packaging (MAP) is the practice of modifying the composition of the internal atmosphere of a package (commonly food packages, drugs, etc.) in order to improve the shelf life. The need for this technology for food arises from the short shelf life of food products such as meat, fish, poultry, and dairy in the presence of oxygen. In food, oxygen is readily available for lipid oxidation reactions. Oxygen also helps maintain high respiration rates of fresh produce, which contribute to shortened shelf life. From a microbiological aspect, oxygen encourages the growth of aerobic spoilage microorganisms. Therefore, the reduction of oxygen and its replacement with other gases can reduce or delay oxidation reactions and microbiological spoilage. Oxygen scavengers may also be used to reduce browning due to lipid oxidation by halting the auto-oxidative chemical process. Besides, MAP changes the gaseous atmosphere by incorporating different compositions of gases.\nThe modification process generally lowers the amount of oxygen (O2) in the headspace of the package. Oxygen can be replaced with nitrogen (N2), a comparatively inert gas, or carbon dioxide (CO2).\nA stable atmosphere of gases inside the packaging can be achieved using active techniques, such as gas flushing and compensated vacuum, or passively by designing “breathable” films.\nHistory.\nThe first recorded beneficial effects of using modified atmosphere date back to 1821. Jacques Étienne Bérard, a professor at the School of Pharmacy in Montpellier, France, reported delayed ripening of fruit and increased shelf life in low-oxygen storage conditions. Controlled atmosphere storage (CAS) was used from the 1930s when ships transporting fresh apples and pears had high levels of CO2 in their holding rooms in order to increase the shelf life of the product. In the 1970s MA packages reached the stores when bacon and fish were sold in retail packs in Mexico. Since then development has been continuous and interest in MAP has grown due to consumer demand.\nTheory.\nAtmosphere within the package can be modified passively or actively. In passive MAP, the high concentration of CO2 and low O2 levels in the package is achieved over time as a result of respiration of the product and gas transmission rates of the packaging film. This method is commonly used for fresh respiring fruits and vegetables. Reducing O2 and increasing CO2 slows down respiration rate, conserves stored energy, and therefore extended shelf life. On the other hand, active MA involves the use of active systems such as O2 and CO2 scavengers or emitters, moisture absorbers, ethylene scavengers, ethanol emitters and gas flushing in the packaging film or container to modify the atmosphere within the package. \nThe mixture of gases selected for a MA package depends on the type of product, the packaging materials and the storage temperature. The atmosphere in an MA package consists mainly of adjusted amounts of N2, O2, and CO2. Reduction of O2 promotes delay in deteriorative reactions in foods such as lipid oxidation, browning reactions and growth of spoilage organisms. Low O2 levels of 3-5% are used to slow down respiration rate in fruits and vegetables. In the case of red meat, however, high levels of O2 (~80%) are used to reduce oxidation of myoglobin and maintain an attractive bright red color of the meat. Meat color enhancement is not required for pork, poultry and cooked meats; therefore, a higher concentration of CO2 is used to extend the shelf life. Levels higher than 10% of CO2 are phytotoxic for fruit and vegetables, so CO2 is maintained below this level. N2 is mostly used as a filler gas to prevent pack collapse. In addition, it is also used to prevent oxidative rancidity in packaged products such as snack foods by displacing atmospheric air, especially oxygen, therefore extending shelf life. The use of noble gases such as helium (He), argon (Ar) and xenon (Xe) to replace N2 as the balancing gas in MAP can also be used to preserve and extend the shelf life of fresh and minimally processed fruits and vegetables. Their beneficial effects are due to their higher solubility and diffusivity in water, making them more effective in displacing O2 from cellular sites and enzymatic O2 receptors. \nThere has been a debate regarding the use of carbon monoxide (CO) in the packaging of red meat due to its possible toxic effect on packaging workers. Its use results in a more stable red color of carboxymyoglobin in meat, which leads to another concern that it can mask evidence of spoilage in the product.\nEffect on microorganisms.\nLow O2 and high CO2 concentrations in packages are effective in limiting the growth of Gram negative bacteria, molds and aerobic microorganisms, such as \"Pseudomonas\" spp. High O2 combined with high CO2 could have bacteriostatic and bactericidal effects by suppression of aerobes by high CO2 and anaerobes by high O2. CO2 has the ability to penetrate bacterial membrane and affect intracellular pH. Therefore, lag phase and generation time of spoilage microorganisms are increased resulting in shelf life extension of refrigerated foods. Since the growth of spoilage microorganisms are suppressed by MAP, the ability of the pathogens to grow is potentially increased. Microorganisms that can survive under low oxygen environment such as \"Campylobacter jejuni\", \"Clostridium botulinum\", \"E. coli\", \"Salmonella\", \"Listeria\" and \"Aeromonas hydrophila\" are of major concern for MA packaged products. Products may appear organoleptically acceptable due to the delayed growth of the spoilage microorganisms but might contain harmful pathogens. This risk can be minimized by use of additional hurdles such as temperature control (maintain temperature below 3 degrees C), lowering water activity (less than 0.92), reducing pH (below 4.5) or addition of preservatives such as nitrite to delay metabolic activity and growth of pathogens.\nPackaging materials.\nFlexible films are commonly used for products such as fresh produce, meats, fish and bread seeing as they provide suitable permeability for gases and water vapor to reach the desired atmosphere. Pre-formed trays are formed and sent to the food packaging facility where they are filled. The package headspace then undergoes modification and sealing. Pre-formed trays are usually more flexible and allow for a broader range of sizes as opposed to thermoformed packaging materials as different tray sizes and colors can be handled without the risk of damaging the package. Thermoformed packaging however is received in the food packaging facility as a roll of sheets. Each sheet is subjected to heat and pressure, and is formed at the packaging station. Following the forming, the package is filled with the product, and then sealed. The advantages that thermoformed packaging materials have over pre-formed trays are mainly cost-related: thermoformed packaging uses 30% to 50% less material, and they are transported as rolls of material. This will amount in significant reduction of manufacturing and transportation costs.\nWhen selecting packaging films for MAP of fruits and vegetables the main characteristics to consider are gas permeability, water vapor transmission rate, mechanical properties, transparency, type of package and sealing reliability. Traditionally used packaging films like LDPE (low-density polyethylene), PVC (polyvinyl chloride), EVA (ethylene-vinyl acetate) and OPP (oriented polypropylene) are not permeable enough for highly respiring products like fresh-cut produce, mushrooms and broccoli. As fruits and vegetables are respiring products, there is a need to transmit gases through the film. Films designed with these properties are called permeable films. Other films, called barrier films, are designed to prevent the exchange of gases and are mainly used with non-respiring products like meat and fish.\nMAP films developed to control the humidity level as well as the gas composition in the sealed package are beneficial for the prolonged storage of fresh fruits, vegetables and herbs that are sensitive to moisture. These films are commonly referred to as modified atmosphere/modified humidity packaging (MA/MH) films.\nEquipment.\nIn using form-fill-seal packaging machines, the main function is to place the product in a flexible pouch suitable for the desired characteristics of the final product. These pouches can either be pre-formed or thermoformed. The food is introduced into the pouch, the composition of the headspace atmosphere is changed within the package; it is then heat sealed. These types of machines are typically called pillow-wrap, which horizontally or vertically form, fill and seal the product. Form-fill-seal packaging machines are usually used for large scale operations.\nIn contrast, chamber machines are used for batch processes. A filled pre-formed wrap is filled with the product and introduced into a cavity. The cavity is closed and vacuum is then pulled on the chamber and the modified atmosphere is inserted as desired. Sealing of the package is done through heated sealing bars, and the product is then removed. This batch process is labor-intensive and thus requires a longer period of time; however, it is relatively cheaper than packaging machines which are automated.\nAdditionally, snorkel machines are used to modify the atmosphere within a package after the food has been filled. The product is placed in the packaging material and positioned into the machine without the need of a chamber. A nozzle, which is the snorkel, is then inserted into the packaging material. It pulls a vacuum and then flushes the modified atmosphere into the package. The nozzle is removed and the package is heat sealed. This method is suitable for bulk and large operations.\nProducts.\nMany products such as red meat, seafood, minimally processed fruits and vegetables, salads, pasta, cheese, bakery goods, poultry, cooked and cured meats, ready meals and dried foods are packaged under MA. A summary of optimal gas mixtures for MA products is shown in the following table.\nModified Atmosphere Packaging for different food products and optimal gas mixtures", "Engineering,_Manufacturing": 0.9998989105, "qwen": "Yes"}
{"id": "10993213", "revid": "35181419", "url": "https://en.wikipedia.org/wiki?curid=10993213", "title": "Punch down tool", "text": "A punch down tool, punchdown tool, IDC tool, or a Krone tool (named after the Krone LSA-PLUS connector), is a small hand tool used by telecommunication and network technicians. It is used for inserting wire into insulation-displacement connectors on punch down blocks, patch panels, keystone modules, and surface mount boxes (also known as biscuit jacks).\nDescription and use.\nMost punch down tools are of the impact type, consisting of a handle, an internal spring mechanism, and a removable slotted blade. To use the punch down tool, a wire is pre-positioned into a slotted post on a punch block, and then the punch down tool is pressed down on top of the wire, over the post. Once the required pressure is reached, an internal spring is triggered, and the blade pushes the wire into the slot, simultaneously cutting the insulation and securing the wire. The tool blade does not cut through the wire insulation to make contact, but rather the sharp edges of the slot in the contact post itself slice through the insulation. \nHowever, the punch down tool blade also is usually used to cut off excess wire, in the same operation as making the connection; this is done with a sharp edge of the punch down tool blade trapping the wire to be cut against the plastic punch block. If this cutoff feature is heavily used, the tool blade must be resharpened or replaced from time to time. Tool blades without the sharp edge are also available; these are used for continuing a wire through a slotted post to make connections with another slotted post (\"daisy-chained\" wiring).\nFor light-duty use, there are also less-expensive punch down tools with fixed blades and no impact mechanism. These low-cost tools are more time-consuming for making reliable connections, and can cause muscle fatigue when used for large numbers of connections.\nTo accommodate different connector types, 66, 110, BIX and krone blocks require different blades. Removable blades for 66 or 110 are almost always double-ended. Some blades have one end that only inserts the wire for daisy-chain wiring from post to post, and another end that inserts wire and trims the excess length for termination at a post. Other blades have a cutting 66 blade on one end and a cutting 110 blade on the other. Krone blades require a separate scissor-like mechanism for trimming the wire.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "11004513", "revid": "1164395576", "url": "https://en.wikipedia.org/wiki?curid=11004513", "title": "Trailer brake controller", "text": "A brake controller is usually an original equipment manufacturer or aftermarket-installed device or module. It is mounted to the tow vehicle's driver's-side dashboard area, and engages a trailer's electrical braking system either time delayed, or in proportion to the tow vehicle's brake engagement when slowing down or coming to a halt. A brake controller is not needed with a trailer surge braking system unless using modern electric over hydraulic devices. The trailer in this case usually has either electric friction brakes or electric-hydraulic trailer brake actuators.\nMost basic brake controllers will generally have a plus-minus gain adjustment. The tow vehicle operator sets the gain as high as possible but without the trailer brakes locking up after making a few test stops. The heavier the trailer, the higher the gain adjustment is set and therefore the less chances of wheel lock-up.\nA wide range of trailers contain trailer brakes (for example, larger boat trailers, horse trailers, covered utility trailers, enclosed trailers, travel trailers including small and longer tent trailers and car carriers). Smaller trailers may not contain trailer brakes (for example, basic utility trailers). It is recommended that, if the total trailer weight is over a couple thousand kilograms, the trailer have some sort of braking system, and the tow vehicle be equipped with a brake controller.\nTypes.\nThere are different types of brake controllers currently or previously on the market.\nAir-actuated electric brake controller.\nThis controller uses the air pressure of the brake system on a vehicle with pneumatic brakes to provide a current to control the electric brakes of a trailer.\nHydraulic actuated electric controller.\nThis controller uses the hydraulic pressure of the brake system on a vehicle with hydraulic brakes to provide a current to control the electric brakes of a trailer. Some truck manufacturers offers this as an OEM option, like Ford with its Ford TowCommand.\nPedal-mounted pressure pad proportional controller.\nA separate sensor is mounted on the brake pedal to connect to the controller.\nProportional brake controller.\nSenses the deceleration of the vehicle through a pendulum or similar device to apply a suitable current for braking of the trailer.\nSurge brake.\nWhen the tow vehicle slows down the trailer pushes against it, an actuator applies force to its master cylinder and the hydraulic pressure is transferred to the brakes\nTime-delayed brake controller.\nApplies brake current with a ramp-up over time to a certain level set by the driver.", "Engineering,_Manufacturing": 0.9994766116, "qwen": "Yes"}
{"id": "45687154", "revid": "35936988", "url": "https://en.wikipedia.org/wiki?curid=45687154", "title": "CNC plunge milling", "text": "CNC plunge milling, also called z-axis milling, is a CNC milling process. In this process, the feed is provided linearly along the tool axis while doing CNC processing. \nPlunge milling is effective for the rough machining process of complex shape or free form shapes like impeller parts. In multi axis plunge milling, the optimization of plunge cutter section selection and generating the tool path for free form surface is very important to improve the efficiency and effectiveness.\nIn plunge milling, after each plunge the milling cutter is offset by some value and then the material surface is removed in the form of lunula. The material removal rate is computed by area of lunula and the feed rate. At the entry and exit of milling cutter, the radial offset has not any influence on the condition of surface.\nAt the maximum cutting velocity, the surface obtained is clean whatever the feed rate per tooth on entry but on exit the high value of feed rate gives the deteriorated surface. The surface roughness value always increases with feed rate in plunge milling. The simulation of dynamic uncut chip thickness which is generated by plunge milling can be done by tracking the position of plunge cutter center. This simulation shows the regenerative effect with variation of phase difference.\nThen the model of uncut chip thickness and cutting force coefficient with cutting edge radius are entered into time domain model. Finally, with the help of time domain solution the stability of machine and vibrations are estimated.\nThe cutting parameters play a key role in plunge milling. The cutting force and machine stability both are influenced by machining parameters. Frequency domain model can be used to estimate the machining stability.\nAdvantages of CNC plunge milling.\nThe plunge milling has following advantage over conventional milling-", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "45689616", "revid": "2584239", "url": "https://en.wikipedia.org/wiki?curid=45689616", "title": "Freeform surface machining", "text": "Freeform surface or complex surfaces are widely manufactured nowadays. The industries which most often manufactures free-form surfaces are basically aerospace, automotive, die mold industries, bio medical and power sector for turbine blades manufacturing. Generally 3 or 5 axis CNC milling machine is used for this purpose. The manufacturing process of free form surface is not an easy job as the tool path generation in present CAM technology is generally based on geometric computation so tool path are not optimum. The geometry can also be not described explicitly so errors and discontinuities occurrence in the solid structure cannot be avoided. Free-form surfaces are machined with the help of different tool path generation method like adaptive iso-planar tool path generation, constant scallop tool path generation, adaptive iso-parametric method, iso-curvature, isophote and by other methods. The different methods are chosen based on the parameters which is needed to be optimized.\nOptimization of free-form surface machining.\nCAM software generally creates a tool path without considering any mechanics process. These causes risk of tool damage, tool deflection and errors on surface finish. By minimizing the forces we can increase tool life. Different optimization method can be used considering process parameters like feed rate, spindle speed, steps, tool diameter, magnitude and preset maximum force. The optimization can be done for minimum machining time, minimum tool travel, minimum production cost or for good surface finish. Efficiency of surface machined is also considered by maximum scallop height and by gouging. Gouging are the main reason for discrepancies of surface accuracy and texture specification. It also causes damage to part,s surface and machine tool. Scallop height tolerance help us in measuring the quality of free-form surface. Selection of proper topology result in minimum path length. In CAM software choosing NURBS to create surface is considered to be good method for presenting surface as it is accepted by both IGES and STEP files of CAM software.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "45690256", "revid": "35936988", "url": "https://en.wikipedia.org/wiki?curid=45690256", "title": "CNC riveting", "text": "CNC riveting is a CNC process used for obtaining permanent mechanical fastening of geometrical shapes, ranging from simple to complex shapes, such as aircraft fuselages. This is done in a shorter duration of time with a high riveting rate. The process is fast, robust, and is flexible in nature; thus improving its usage and providing reliability to the riveted joint along with the final product quality. CNC riveting can be used for a variety of operations ranging from riveting and fastening belts, skin panels, shear ties, and other internal fuselage components.\nThe CNC Riveting machines generally consist of a solid frame made of welded steel and aluminum frames used for protection fitted with polycarbonate panes. The dynamic drive of the coordinates axes is achieved by a recirculating ball and screw, servo motors and motion control units that make the high-speed movement possible. For the mounting of the riveting units, solid C Frames are used. The riveting program can be given various parameters and these can be changed or altered as desired to be CNC programs as per the requirement.\nCNC riveting machine variants.\nCNC duct riveting cell.\nA CNC controlled automatic riveting work cell with a knee type design drill machine that has sixty-inch throat depth with four positions on the upper head. This machine can apply sixteen pounds of upset force. This machine is equipped with dual drill spindles, one for carrying out drilling and other for deburring. It was developed for the fabrication of tubular assemblies, which are fed into the throat of the machine over an eight-inch square lower knee. The CNC controlled four axis positioning system presents the part to the machine that carries out the riveting.\nCNC riveting machines with stationary machine table.\nThese CNC machines act as stand-alone workstations for heavy and bigger workpieces. They are simple in design and require work holding fixtures only, so the clamping and component query devices are much more affordable.\nCNC riveting machines with Indexing Tables.\nThese special purpose CNC riveting machines have different sizes of indexing tables that be composed of different coordinate axes and riveting machines. These machines have different versions for the particular application and are configured accordingly. The coordinate system has linear units and recirculating ball screws, and an index table that is electrically operated with a brake motor. It has two to four fixed indexing stations, and the index table are NC flexible rotary indexing tables which are actuated by two hand controls or by a pedal switch. The machine has an automatic tool changer.\nCNC riveting machines with transfer system.\nThese CNC riveting machines are made for use in manufacturing lines. The fixtures are coded and interfaces are customized to make the connection of several CNC riveting machines and linking them with other manufacturing systems, making it possible to obtain a high degree of automation.\nMultiple axes CNC riveting cell.\nThis is the latest technological development in automated fastening. This technology is versatile and can be used for riveting of high curvature fuselage panels to low curvature wing panels, bulkheads, floor etc. The tooling changeover is minimized thus part throughput is maximized.\nAdvantages.\nThe main advantages of this type of CNC riveting machine are that it can use a variable minimum distance between rivets, and rivets of different length or heights can be used. High flexibility and change over time due to programmable memory. It can process many workpieces and different rivets can be used in one operation. Picking and placing operations are done in parallel with the primary operation time, saving money. Menu based navigation makes the programming fluid. High acceleration rate with high positioning accuracy. ", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "45704362", "revid": "1161198397", "url": "https://en.wikipedia.org/wiki?curid=45704362", "title": "Automatic tool changer", "text": "In machining, an automatic tool changer (ATC) is used in computerized numerical control (CNC) machine tools to improve the production and tool carrying capacity of the machine. ATCs change tools rapidly, reducing non-productive time. They are generally used to improve the capacity of the machines to work with a number of tools. They are also used to change worn out or broken tools. They are one more step towards complete automation.\nDescription.\nSimple CNC machines work with a single tool. Turrets can work with a large number of tools. But if even more tools are required, then an ATC is needed. The tools are stored in a magazine. This allows the machine to work with a large number of tools without operator intervention. \nThe main parts of an automatic tool changer are the base, the gripper arm, the tool holder, the support arm, and the tool magazines. \nAlthough the ATC increases the reliability, speed, and accuracy of a machine, it creates more challenges compared to manual tool change. For example, the tooling used must be easy to center, be easy for the changer to grab, and there should be a simple way to provide the tool's self-disengagement. Tools used in ATC are secured in tool holders specially designed for this purpose.\nTypes of tool changers.\nDepending on the shape of the magazine, an ATC can be of two types: 1) Drum Type changers are used when the number of tools is lower than 30. The tools are stored on the periphery of the drum. \n2) Chain type changers are used when the number of tools is higher than 30 (The number is different depending on the design and manufacturer. It is important to note that the number of tools for the drum type is fewer than the chain type). But the tool search speed will be lower in this case.\nAutomatic tool changer mechanism.\nAfter receiving the tool change command, the tool to be changed will assume a fixed position known as the \"tool change position\". The ATC arm comes to this position and picks up the tool. The arm swivels between the machine turret and the magazine. It will have one gripper on each of the two sides. Each gripper can rotate 90°, to deliver tools to the front face of the turret. One will pick up the old tool from the turret and the other will pick up the new tool from the magazine. It then rotates 180° and places the tools into their needed position.\nTool changers on sheet metal working machinery.\nATCs were first used on chip-removal machines, such as mills and lathes. Systems for automatic rearrangement of tools have also been used on sheet metal working machinery. Panel benders have an integrated CNC-controlled device that allows punches to be moved according to the size of the part. Automated tool changes on press brakes were limited to machines integrated on a robotic bending cell. Typically a 6-axis robot used for handling sheet metal blanks is also in charge of changing punches and dies between different batches.\nSince the 2020s automatic tool changers have appeared on non-robotic press brakes. The most common configuration is a tool rack on the side of the press brakes, with a shuttle picking up tools and positioning them where needed. This reduces physical strain on the operator and increases overall productivity.\nFunctions of a tool changer.\nThe use of automatic changers increases the productive time and reduces unproductive time. It provides the storage of the tools which are returned automatically to the machine tool after carrying out the required operations, increases the flexibility of the machine tool, makes it easier to change heavy and large tools, and permits the automatic renewal of cutting edges.", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "9384886", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=9384886", "title": "Burn-in oven", "text": "Burn-in ovens in electronics device fabrication, are designed for dynamic and static burn-in of integrated circuits and other electronic devices, including laser diodes. Typical sizes are from under ten to over , with air or nitrogen configurations. Operating temperatures can go over , and can use both single and multiple temperature settings.\nBurn-in oven applications can be used in numerous different applications such as high-dissipation forward bias, high-temperature reverse bias, dynamic and static burn-in of microprocessors and other semiconductor devices.\nBurn-in ovens are considered a type of batch oven. Other types of batch ovens are bench/laboratory, reach-in, walk in/truck in, and clean process.\nOne company builds systems designed for burn-in of low power laser diodes up to 1A and high power laser diodes up to 300A.", "Engineering,_Manufacturing": 0.9998432398, "qwen": "Yes"}
{"id": "9401077", "revid": "1159159820", "url": "https://en.wikipedia.org/wiki?curid=9401077", "title": "Color LaserWriter", "text": "The Color LaserWriter was a line of PostScript four-color laser printers manufactured by Apple Computer, Inc. in the mid-1990s. These printers were compatible with PCs and Apple's own Macintosh line of computers; these printers were also able to connect to large networks by way of the use of an 10baseT Ethernet port. Two models were released. \nColor LaserWriter 12/600 PS.\nA PostScript printer, the Color LaserWriter 12/600 PS color laser printer was intended for small business and consumers with high printing requirements. The Windows-compatible driver was of interest due to its ability generate Postscript files (.ps) for later printing.\nThis printer was released one year before its replacement with the Color LaserWriter 12/660 PS, which had the same specifications as the 12/600 PS, but was sold at a lower price.\nColor LaserWriter 12/660 PS.\nThe Color LaserWriter 12/660 PS is a color laser printer introduced by Apple in October 1996. The printer became a workhorse used in Kinko's copy stores across the United States. The printer's weight, size, speed of printing, and high cost of purchase, operation, and maintenance were its chief drawbacks.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "3140544", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=3140544", "title": "Alumel", "text": "Alumel is an alloy consisting of approximately 95% nickel, 2% aluminium, 2% manganese, and 1% silicon. This magnetic alloy is used to make the negative conductors of ANSI Type K (chromel-alumel) thermocouples and thermocouple extension wire. Alumel is a registered trademark of Concept Alloys, Inc. ", "Engineering,_Manufacturing": 0.9999979734, "qwen": "Yes"}
{"id": "236898", "revid": "7243169", "url": "https://en.wikipedia.org/wiki?curid=236898", "title": "Engineer's blue", "text": "Engineer's blue (also known as scraping blue, Prussian blue, or simply bluing) is a highly pigmented paste used to assist in the mating of two or more components.\nHistory.\nJoseph Whitworth popularized the first practical method of making accurate flat surfaces, during the 1830s, by using engineer's blue and scraping techniques on three trial surfaces. Prior to his scraping technique, the same three plate method was employed using polishing techniques, giving less accurate results. This improvement led to an explosion of development of precision instruments using these flat surface generation techniques as a basis for further construction of precise shapes.\nPreparation.\nEngineer's blue is prepared by mixing Prussian blue with a non-drying oily material (for example, grease). The coloured oil is rubbed onto a reference surface, and the workpiece is then rubbed against the coloured reference; the transfer (by contact) of the pigment indicates the position of high spots on the workpiece or conversely highlight low points. This method has been used to test the flatness of surfaces and the trueness of a bearing assembly.\nThe fitter may be told to \"blue it up\" when using this piece of equipment.\nUse in toolmaking.\nPrussian blue is widely used by tool makers when the core and cavity of a mould is matched during final assembly. It is also used in other tooling applications, especially during assembly, such as stamping tools and pressure die casting tools. A thin coating of Prussian blue is applied (usually with a paint brush) on the \"insert\", regardless of the shape or contour, of the mould or tool before the matching is done with the mating part. If the Prussian blue (generally called just \"blue\") appears evenly on the mating area, it is considered, by the tool makers, as \"good matching\", indicating a good final product from the tool. Usually no tool would be transferred to testing or production without \"blue matching\", (a term generally used by tool makers in Asia). Prussian blue is considered as an integral part of precision tool making.", "Engineering,_Manufacturing": 0.9966464043, "qwen": "Yes"}
{"id": "34280377", "revid": "1166097720", "url": "https://en.wikipedia.org/wiki?curid=34280377", "title": "Types of press tools", "text": "Press tools are commonly used in hydraulic, pneumatic, and mechanical presses to produce the sheet metal components in large volumes. Generally press tools are categorized by the types of operation performed using the tool, such as blanking, piercing, bending, forming, forging, trimming etc. The press tool will also be specified as a blanking tool, piercing tool, bending tool etc.\nClassification of press tools.\nBlanking tool.\nIn blanking, metal obtained after cutting is not a scrap if it is usable.\nPiercing tool.\nPiercing involves cutting of clean holes with a resulting scrap slug. The operation is called die cutting and can also produce flat components where the die, the shaped tool, is pressed into a sheet material employing a shearing action to cut holes. This method can be used to cut parts of different sizes and shapes in sheet metal, leather and many other materials. \nCut off tool.\nIt is a shearing operation in which blanks are separated from a sheet metal strip by cutting the opposite sides of the part in sequence.\nParting off tool.\nThis is similar to a cutoff tool, in that a discrete part is cut from a sheet or strip of metal along a desired geometric path. The difference between a cutoff and a parting is that a cutoff can be nestled perfectly on the sheet metal, due to its geometry. With cutoffs, the cutting of sheet metal can be done over one path at a time and there is practically no waste of material. With partings, the shape can not be nestled precisely. Parting involves cutting the sheet metal along two paths simultaneously. Partings waste a certain amount of material, that can be significant.\nTrimming tool.\nWhen cups and shells are drawn from flat sheet metal the edge is left wavy and irregular, due to uneven flow of metal. Shown is flanged shell, as well as the trimmed ring removed from around the edge. While a small amount of Material is removed from the side of a component in trimming tool.\nShaving tool.\nShaving removes a small amount of material around the edges of a previously blanked stampings or piercing. A straight, smooth edge is provided and therefore shaving is frequently performed on instrument parts, watch and clock parts and the like. Shaving is accomplished in shaving tools especially designed for the purpose.\nit is also required proper die clearance\nForming tool.\nForming is the operation of deforming a part in curved profile.\nForming tools apply more complex forms to work pieces. The line of bend is curved instead of straight and the metal is subjected to plastic flow or deformation.\nDrawing tool.\nDrawing tools transform flat sheets of metal into cups, shells or other drawn shapes by subjecting the material to severe plastic deformation. Shown in fig is a rather deep shell that has been drawn from a flat sheet. It is an axial elongation through the application of axial force.\nThis type of Press tool is used to perform only one particular operation therefore classified under stage tools.\nProgressive tool.\nA progressive tool differs from a stage tool in the following respect: in a progressive tool the final component is obtained by progressing the sheet metal or strip in more than one stage. At each stage the tool will progressively shape the component towards its final shape, with the final stage normally being cutting-off.\nCompound tool.\nThe compound tool differs from progressive and stage tools by the arrangement of the punch and die. It is an inverted tool where blanking and piercing takes place in a single stage and also the blanking punch will act as the piercing die. that means punch will be to the bottom side of the tool and piercing punches to top side of the tool.The burr forms only one side.\nCombination tool.\nIn a combination tool two or more operations such as bending and trimming will be performed simultaneously. Two or more operations such as forming, drawing, extruding, embossing may be combined on the component with various cutting operations like blanking, piercing, broaching and cut off takes place- it can perform a cutting and non cutting operations in a single tool.\nGeneral press tool construction.\nThe general press tool construction will have following elements:- \nCutting force in press tool.\nIn general, cutting force can be calculated using the formula:\nCF =L x T x ζmax\nCutting force will be in Newton (N)\nWhere,\nL = Cut length in mm,(perimeter of profile to be cut)\nEx: 40 mm square to be cut will have cut length of 160 mm\nT = Sheet metal thickness in mm,\nζmax = Maximum shear strength of sheet metal in MPa\nStripping force.\nStripping force is the force required to eject the strip from the punches, which helps the strip to go forward for the next operation Stripping force will be usually 10 to 20 % of cutting force (CF)\nPress force.\nThe Press force is the cutting force added to the stripping force:\nPress Force = Cutting force + Stripping force", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "34281237", "revid": "46166935", "url": "https://en.wikipedia.org/wiki?curid=34281237", "title": "ISI mark", "text": "The ISI mark is a standards-compliance mark for industrial products in India since 1950. The mark certifies that a product conforms to an Indian standard (IS) developed by the Bureau of Indian Standards (BIS), the national standards body of India. The ISI mark is by far the most certification mark in the Indian subcontinent. The \"ISI\" is an initialism of \"Indian Standards Institution\", the name of the national standards body at 1 January 1978, when it was renamed to the Bureau of the Indian Standards. The ISI mark is mandatory for a certain products to be sold in India, such as many of the electrical appliances like switches, electric motors, wiring cables, heaters, kitchen appliances, etc., and other products like Portland cement, LPG valves, LPG cylinders, automotive tyres, etc. In the case of most other products, ISI marks are optional.\nCounterfeiting.\nIt is very common in India to find products with fake ISI marks. That is, industrial traders cheat customers by affixing ISI marks on the product without actually certified. Fake ISI marks usually do not carry\nFor example, if a kitchen grinder's box has a small ISI mark on it with the ISI code of the appliance's wire, one can conclude that the wire is BIS-certified but the appliance itself is not an BIS-certified product. Counterfeiting ISI marks is a punishable offence by the law, but enforcement is uncommon.\nReferences.\n9. ISI Mark Certification Process, Documents Required, and list of the Products under BIS Certification Scheme - Aleph INDIA\n10. ISI/BIS Certification: A Gateway to the Indian Market, ISI mark certification mandatory Products- Brand Liaison", "Engineering,_Manufacturing": 0.9975981712, "qwen": "Yes"}
{"id": "11855268", "revid": "41840956", "url": "https://en.wikipedia.org/wiki?curid=11855268", "title": "AETHRA Componentes Automotivos", "text": "AETHRA is a Brazilian company, founded in 1974 in Minas Gerais, that applies technology to develop and manufacture automotive systems to the global market.\nAETHRA is present in the industrial sector over 30 years. Since early foundation, Hammer Indústria de Autopeças Ltda, started to produce stamped components, establishing as auto parts supplier in the Brazilian market. With increasing market demands, Aethra expanded to new units to meet both the development of automotive components for new Auto vehicles, and the manufacture of tooling for the production of stamped components.\nEmerging from such intensive investments, AETHRA became one of the largest tooling construction companies in Latin America, also including surface parts, and has attained in the manufacturing of stamped components either small, medium and large-sized, also AETHRA began to supply assemblies and develop new products, promoting the continuous growth of its activities in engineering, tooling and mass production expansion.\nIn 2003, AETHRA has included in its production the assembly of complete truck cabins. AETHRA has become major player in vehicle development in the Brazilian market, offering everything from engineering services with modern CAD / CAM / CAE workstations, as well as in the construction of soft-toolings, prototypes, 5D laser cutting, development of final tooling, welding lines, assembling and mass production with JIT logistics in several automotive production poles in Brazil.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "2052726", "revid": "33727592", "url": "https://en.wikipedia.org/wiki?curid=2052726", "title": "Wafer-scale integration", "text": "Wafer-scale integration (WSI) is a rarely used system of building very-large integrated circuit (commonly called a \"chip\") networks from an entire silicon wafer to produce a single \"super-chip\". Combining large size and reduced packaging, WSI was expected to lead to dramatically reduced costs for some systems, notably massively parallel supercomputers. The name is taken from the term very-large-scale integration, the state of the art when WSI was being developed.\nOverview.\nIn the normal integrated circuit manufacturing process, a single large cylindrical crystal (boule) of silicon is produced and then cut into disks known as wafers. The wafers are then cleaned and polished in preparation for the fabrication process. A photographic process is used to pattern the surface where material ought to be deposited on top of the wafer and where not to. The desired material is deposited and the photographic mask is removed for the next layer. From then on the wafer is repeatedly processed in this fashion, putting on layer after layer of circuitry on the surface.\nMultiple copies of these patterns are deposited on the wafer in a grid fashion across the surface of the wafer. After all the possible locations are patterned, the wafer surface appears like a sheet of graph paper, with grid lines delineating the individual chips. Each of these grid locations is tested for manufacturing defects by automated equipment. Those locations that are found to be defective are recorded and marked with a dot of paint (this process is referred to as \"inking a die\" and more modern wafer fabrication techniques no longer require physical markings to identify defective die). The wafer is then sawed apart to cut out the individual chips. Those defective chips are thrown away, or recycled, while the working chips are placed into packaging and re-tested for any damage that might occur during the packaging process.\nFlaws on the surface of the wafers and problems during the layering/depositing process are impossible to avoid, and cause some of the individual chips to be defective. The revenue from the remaining working chips has to pay for the entire cost of the wafer and its processing, including those discarded defective chips. Thus, the higher number of working chips or higher \"yield\", the lower the cost of each individual chip. In order to maximize yield one wants to make the chips as small as possible, so that a higher number of working chips can be obtained per wafer.\nLowering cost.\nThe significant fraction of the cost of fabrication (typically 30%-50%) is related to testing and packaging the individual chips. Further cost is associated with connecting the chips into an integrated system (usually via a printed circuit board). Wafer-scale integration seeks to reduce this cost, as well as improve performance, by building larger chips in a single package – in principle, chips as large as a full wafer.\nOf course this is not easy, since given the flaws on the wafers a single large design printed onto a wafer would almost always not work. It has been an ongoing goal to develop methods to handle faulty areas of the wafers through logic, as opposed to sawing them out of the wafer. Generally, this approach uses a grid pattern of sub-circuits and \"rewires\" around the damaged areas using appropriate logic. If the resulting wafer has enough working sub-circuits, it can be used despite faults.\nChallenges.\nMost yield loss in chipmaking comes from defects in the transistor layers or in the high-density lower metal layers.\nAnother approach – silicon-interconnect fabric (Si-IF) – has neither on the wafer. Si-IF puts only relatively low-density metal layers on the wafer, roughly the same density as the upper layers of a system on a chip, using the wafer only for interconnects between tightly-packed small bare chiplets.\nProduction attempts.\nMany companies attempted to develop WSI production systems in the 1970s and 1980s, but all failed. Texas Instruments and ITT Corporation both saw it as a way to develop complex pipelined microprocessors and re-enter a market where they were losing ground, but neither released any products.\nGene Amdahl also attempted to develop WSI as a method of making a supercomputer, starting Trilogy Systems in 1980 and garnering investments from Groupe Bull, Sperry Rand and Digital Equipment Corporation, who (along with others) provided an estimated $230 million in financing. The design called for a 2.5\" square chip with 1200 pins on the bottom.\nThe effort was plagued by a series of disasters, including floods which delayed the construction of the plant and later ruined the clean-room interior. After burning through about of the capital with nothing to show for it, Amdahl eventually declared the idea would only work with a 99.99% yield, which wouldn't happen for 100 years. He used Trilogy's remaining seed capital to buy Elxsi, a maker of VAX-compatible computers, in 1985. The Trilogy efforts were eventually ended and \"became\" Elxsi.\nIn 1989 Anamartic developed a wafer stack memory based on the technology of Ivor Catt, but the company was unable to ensure a large enough supply of silicon wafers and folded in 1992.\nWafer-scale devices in production.\nCerebras Systems processor.\nOn August 19, 2019, American computer systems company Cerebras Systems presented their development progress of WSI for deep learning acceleration. Cerebras' Wafer-Scale Engine (WSE-1) chip is 46,225mm2 (215mm × 215mm), around 56× larger than the largest GPU die. It is manufactured by TSMC using their 16nm process. The WSE-1 features 1.2 trillion transistors, 400,000 AI cores, 18GB of on-chip SRAM, 100Pbit/s on-wafer fabric bandwidth, and 1.2Pbit/s I/O off-wafer bandwidth. The price and clock rate have not been disclosed. In 2020, the company's product, the CS-1, was tested in computational fluid dynamics simulations. Compared to the Joule Supercomputer at NETL, the CS-1 was 200 times faster, while using much less power.\nIn April 2021, Cerebras announced the WSE-2, with twice the number of transistors and 100% claimed yield, which is achieved by designing a system in which any manufacturing defect can be bypassed. The Cerebras CS-2 system, which incorporates the WSE-2, is in serial production.", "Engineering,_Manufacturing": 0.9999786615, "qwen": "Yes"}
{"id": "1924637", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1924637", "title": "Shielding gas", "text": "Shielding gases are inert or semi-inert gases that are commonly used in several welding processes, most notably gas metal arc welding and gas tungsten arc welding (GMAW and GTAW, more popularly known as MIG (Metal Inert Gas) and TIG (Tungsten Inert Gas), respectively). Their purpose is to protect the weld area from oxygen, and water vapour. Depending on the materials being welded, these atmospheric gases can reduce the quality of the weld or make the welding more difficult. Other arc welding processes use alternative methods of protecting the weld from the atmosphere as well – shielded metal arc welding, for example, uses an electrode covered in a flux that produces carbon dioxide when consumed, a semi-inert gas that is an acceptable shielding gas for welding steel.\nImproper choice of a welding gas can lead to a porous and weak weld, or to excessive spatter; the latter, while not affecting the weld itself, causes loss of productivity due to the labor needed to remove the scattered drops.\nIf used carelessly, shielding gasses can displace oxygen, causing hypoxia and potentially death.\nCommon shielding gases.\nShielding gases fall into two categories—inert or semi-inert. Only two of the noble gases, helium and argon, are cost effective enough to be used in welding. These inert gases are used in gas tungsten arc welding, and also in gas metal arc welding for the welding of non-ferrous metals. Semi-inert shielding gases, or active shield gases, include carbon dioxide, oxygen, nitrogen, and hydrogen. These active gases are used with GMAW on ferrous metals. Most of these gases, in large quantities, would damage the weld, but when used in small, controlled quantities, can improve weld characteristics.\nProperties.\nThe important properties of shielding gases are their thermal conductivity and heat transfer properties, their density relative to air, and the ease with which they undergo ionization. Gases heavier than air (e.g. argon) blanket the weld and require lower flow rates than gases lighter than air (e.g. helium). Heat transfer is important for heating the weld around the arc. Ionizability influences how easy the arc starts, and how high voltage is required. Shielding gases can be used pure, or as a blend of two or three gases. In laser welding, the shielding gas has an additional role, preventing formation of a cloud of plasma above the weld, absorbing significant fraction of the laser energy. This is important for CO2 lasers; Nd:YAG lasers show lower tendency to form such plasma. Helium plays this role best due to its high ionization potential; the gas can absorb high amount of energy before becoming ionized.\nArgon is the most common shielding gas, widely used as the base for the more specialized gas mixes.\nCarbon dioxide is the least expensive shielding gas, providing deep penetration, however it negatively affects the stability of the arc and enhances the molten metal's tendency to create droplets (spatter). Carbon dioxide in concentration of 1-2% is commonly used in the mix with argon to reduce the surface tension of the molten metal. Another common blend is 25% carbon dioxide and 75% argon for GMAW.\nHelium is lighter than air; larger flow rates are required. It is an inert gas, not reacting with the molten metals. Its thermal conductivity is high. It is not easy to ionize, requiring higher voltage to start the arc. Due to higher ionization potential it produces hotter arc at higher voltage, provides wide deep bead; this is an advantage for aluminium, magnesium, and copper alloys. Other gases are often added. Blends of helium with addition of 5–10% of argon and 2–5% of carbon dioxide (\"tri-mix\") can be used for welding of stainless steel. Used also for aluminium and other non-ferrous metals, especially for thicker welds. In comparison with argon, helium provides more energy-rich but less stable arc. Helium and carbon dioxide were the first shielding gases used, since the beginning of World War 2. Helium is used as a shield gas in laser welding for carbon dioxide lasers. Helium is more expensive than argon and requires higher flow rates, so despite its advantages it may not be a cost-effective choice for higher-volume production. Pure helium is not used for steel, as it causes an erratic arc and encourages spatter.\nOxygen is used in small amounts as an addition to other gases; typically as 2–5% addition to argon. It enhances arc stability and reduces the surface tension of the molten metal, increasing wetting of the solid metal. It is used for spray transfer welding of mild carbon steels, low alloy and stainless steels. Its presence increases the amount of slag. Argon-oxygen (Ar-O2) blends are often being replaced with argon-carbon dioxide ones. Argon-carbon dioxide-oxygen blends are also used. Oxygen causes oxidation of the weld, so it is not suitable for welding aluminium, magnesium, copper, and some exotic metals. Increased oxygen makes the shielding gas oxidize the electrode, which can lead to porosity in the deposit if the electrode does not contain sufficient deoxidizers. Excessive oxygen, especially when used in application for which it is not prescribed, can lead to brittleness in the heat affected zone. Argon-oxygen blends with 1–2% oxygen are used for austenitic stainless steel where argon-CO2 can not be used due to required low content of carbon in the weld; the weld has a tough oxide coating and may require cleaning.\nHydrogen is used for welding of nickel and some stainless steels, especially thicker pieces. It improves the molten metal fluidity, and enhances cleanness of the surface. It is added to argon in amounts typically under 10%. It can be added to argon-carbon dioxide blends to counteract the oxidizing effects of carbon dioxide. Its addition narrows the arc and increases the arc temperature, leading to better weld penetration. In higher concentrations (up to 25% hydrogen), it may be used for welding conductive materials such as copper. However, it should not be used on steel, aluminum or magnesium because it can cause porosity and hydrogen embrittlement; its application is usually limited only to some stainless steels.\nNitric oxide addition serves to reduce production of ozone. It can also stabilize the arc when welding aluminium and high-alloyed stainless steel.\nOther gases can be used for special applications, pure or as blend additives; e.g. sulfur hexafluoride or dichlorodifluoromethane.\nSulfur hexafluoride can be added to shield gas for aluminium welding to bind hydrogen in the weld area to reduce weld porosity.\nDichlorodifluoromethane with argon can be used for protective atmosphere for melting of aluminium-lithium alloys. It reduces the content of hydrogen in the aluminium weld, preventing the associated porosity. This gas, however, is being used less because it has a strong ozone depletion potential.\nApplications.\nThe applications of shielding gases are limited primarily by the cost of the gas, the cost of the equipment, and by the location of the welding. Some shielding gases, like argon, are expensive, limiting its use. The equipment used for the delivery of the gas is also an added cost, and as a result, processes like shielded metal arc welding, which require less expensive equipment, might be preferred in certain situations. Finally, because atmospheric movements can cause the dispersion of the shielding gas around the weld, welding processes that require shielding gases are often only done indoors, where the environment is stable and atmospheric gases can be effectively prevented from entering the weld area.\nThe desirable rate of gas flow depends primarily on weld geometry, speed, current, the type of gas, and the metal transfer mode being utilized. Welding flat surfaces requires higher flow than welding grooved materials, since the gas is dispersed more quickly. Faster welding speeds, in general, mean that more gas needs to be supplied to provide adequate coverage. Additionally, higher current requires greater flow, and generally, more helium is required to provide adequate coverage than argon. Perhaps most importantly, the four primary variations of GMAW have differing shielding gas flow requirements—for the small weld pools of the short circuiting and pulsed spray modes, about 10 L/min (20 ft3/h) is generally suitable, while for globular transfer, around 15 L/min (30 ft3/h) is preferred. The spray transfer variation normally requires more because of its higher heat input and thus larger weld pool; along the lines of 20–25 L/min (40–50 ft3/h).", "Engineering,_Manufacturing": 0.9999372959, "qwen": "Yes"}
{"id": "29177466", "revid": "48742", "url": "https://en.wikipedia.org/wiki?curid=29177466", "title": "Draw bench", "text": "A draw bench is a machine used to do cold work on a metal, such as changing the shape of the metal without applying heat and applying only pressure.\nMachine construction.\nIt consists of a chain drive, driven by a motor and a set of gears. The other end of the machine consists of a die mounted on a thick steel plate. The workpiece is inserted through the die and clamped on a trolley which then is hooked onto the chain for pulling across.\nDie.\nThe die is usually made of tungsten carbide with a steel housing. The die can be made to any desired shape (round, square, rectangular, triangular, half round, L-shaped, oval etc.).", "Engineering,_Manufacturing": 0.9999996424, "qwen": "Yes"}
{"id": "29199153", "revid": "44881403", "url": "https://en.wikipedia.org/wiki?curid=29199153", "title": "Filler (packaging)", "text": "Fillers (or filling machines) are used for packaging, mainly for food/beverage but for other products as well. These are used to fill either a bottle or a pouch, depending on the product.\nThere are several types of fillers used by the packaging industry. The type of Food or beverage filling machines to be used is usually determined by the type of product to be filled, speed requirements, quality and shelf life expectations, resources availability, technology feasibility and many other variables. Type of food products may range from solid to semi-solids, from liquids to frozen, from hot to cold, from free flowing to highly viscous products etc. This wide range of product characteristics also suggests that filling machines with great flexibility and versatility are the most valuable. There are various filling technologies for liquid and dry products and product filling machines can be rotary or inline, intermittent or continuous motion, semi-automatic or fully automatic with various filling technologies to cater for the huge range of product variables and user requirements, each offering unique advantages. The following are the most common:", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "29211781", "revid": "8349418", "url": "https://en.wikipedia.org/wiki?curid=29211781", "title": "Roll bender", "text": "A roll bender is a mechanical jig having three rollers used to bend a metal bar into a circular arc. The rollers freely rotate about three parallel axes, which are arranged with uniform horizontal spacing. Two outer rollers, usually immobile, cradle the bottom of the material while the inner roller, whose position is adjustable, presses on the topside of the material.\nRoll bending may be done to both sheet metal and bars of metal. If a bar is used, it is assumed to have a uniform cross-section, but not necessarily rectangular, as long as there are no overhanging contours, i.e. positive draft. Such bars are often formed by extrusion. The material to be shaped is suspended between the rollers. The end rollers support the bottomside of the bar and have a matching contour (inverse shape) to it in order to maintain the cross-sectional shape. Likewise, the middle roller is forced against the topside of the bar and has a matching contour to it.\nOperation.\nAfter the bar is initially inserted into the jig, the middle roller is manually lowered and forced against the bar with a screw arrangement. This causes the bar to undergo both plastic and elastic deformation. The portion of the bar between the rollers will take on the shape of a cubic polynomial, which approximates a circular arc. The rollers are then rotated moving the bar along with them. For each new position, the portion of the bar between the rollers takes on the shape of a cubic modified by the end conditions imposed by the adjacent sections of the bar. When either end of the bar is reached, the force applied to the center roller is incrementally increased, the roller rotation is reversed and as the rolling process proceeds, the bar shape becomes a better approximation to a circular arc. During the rolling process, the force applied to the center roller is incrementally increased to gradually bring the arc of the bar to the desired radius. \nPlastic and elastic deformation.\nThe plastic deformation of the bar is retained throughout the process. However, the elastic deformation is reversed as a section of bar leaves the area between the rollers. This spring-back needs to be compensated in adjusting the middle roller to achieve a desired radius. The amount of spring back depends upon the elastic compliance (inverse of stiffness) of the material relative to its ductility. Aluminum alloys, for example, tend to have high ductility relative to their elastic compliance, whereas steel tends to be the other way around. Therefore aluminum bars are more amenable to bending into an arc than are steel bars.", "Engineering,_Manufacturing": 0.999992013, "qwen": "Yes"}
{"id": "198677", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=198677", "title": "Mastercam", "text": "Mastercam is a suite of Computer-Aided Manufacturing (CAM) and CAD/CAM software applications developed by CNC Software, LLC. Founded in Massachusetts in 1983, CNC Software are headquartered in Tolland, Connecticut.\nMastercam is CNC Software's main product. It started as a 2D CAM system with CAD tools that let machinists design virtual parts on a computer screen and also guided computer numerical controlled (CNC) machine tools in the manufacture of parts. Mastercam has been ranked by CIMdata Inc. as the most widely used CAM package in the world since 1994.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "73462795", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=73462795", "title": "Fractional job scheduling", "text": "Fractional job scheduling is a variant of optimal job scheduling in which it is allowed to break jobs into parts and process each part separately on the same or a different machine. Breaking jobs into parts may allow for improving the overall performance, for example, decreasing the makespan. Moreover, the computational problem of finding an optimal schedule may become easier, as some of the optimization variables become continuous. On the other hand, breaking jobs apart might be costly.\nVariants.\nThere are several variants of job scheduling problems in which it is allowed to break jobs apart. They can be broadly classified into preemption and splitting.\nJob scheduling with preemption.\nVarious problems have been studied in job scheduling with preemption. One of them is generalized multiprocessor scheduling (GMS). It has two variants.\nIn both variants, the goal is to find a schedule that minimizes the makespan subject to the preemption constraints.\nFor identical machines, Shchepin and Vakhania prove that with at most formula_3 total preemptions, the problem is NP-hard, whereas McNaughton shows a linear-time algorithm with formula_4 preemptions.\nFor uniform machines, a polynomial algorithm by Gonzalez and Sahni yields at most formula_5 preemptions. Shachnai, Tamir, and Woeginger proved NP-hardness for the case where the number of preemption is strictly less than formula_5. They also presented a PTAS for GMS with a global preemption bound, and another PTAS for GMS with job-wise preemption bound when the number of machines is a fixed constant.\nSoper and Strusevitch study the special case in which at most one preemption is allowed. They show that makespan minimization is polynomial for two machines.\nMany papers study other variants of preemptive scheduling. For example, Liu and Cheng consider single-machine scheduling with job release and delivery dates, where there is no firm bound on the number of preemptions, but each preemption requires spending time on \"job setup\".\nSome works like Blazewicz \"et al.\" or Deng \"et al.\" study preemptive scheduling for jobs with parallelism where jobs must be processed simultaneously on several processors.\nJob scheduling with splitting.\nVarious objectives have been studied. There are many variants including different setup times. In machine scheduling, the \"setup time\" refers to the time required to prepare a machine for a specific job or task. Sequence-dependent setup time is a situation where the setup time required for a job depends on the job that came before it, rather than being constant for all jobs (independent job setup time).\nSerafini assumes unbounded splittings and preemptions and gives polynomial-time algorithms that minimize the maximum tardiness and the maximum weighted tardiness, for uniform and unrelated machines.\nXing and Zhang allow unbounded splittings, and give polynomial algorithms for many optimality criteria (such as makespan, lateness, tardiness, and more), with identical, uniform, and unrelated machines. For the case with independent job setup time, they give a formula_7 approximation algorithm.\nSon et al. study makespan minimization on a single machine with a machine-availability constraint with a lower bound on the length of each part of a job that is split.\nFor identical machines, Shim and Kim suggest a branch and bound algorithm with the objective to minimize total tardiness with independent job setup time. Yalaoui and Chu propose a heuristic to the same problem, with the objective to minimize the makespan. Kim et al. suggest a two-phase heuristic algorithm with the objective of minimizing total tardiness. With the objective to minimize the makespan, Kim studies another variant with family setup time in which no setup is required when parts from the same job are produced consecutively. And, Wang et al. include a learning property that improves the processing time of a job according to the learning effect. The learning has to be restarted if one job is split and processed by a different machine.\nFor uniform machines, Kim and Lee study a variant with dedicated machines (there are some dedicated machines for each job), sequence-dependent setup times, and limited set-up resources (jobs require setup operators that are limited) with the objective to minimize the makespan. Krysta, Sanders, and Vöcking study makespan minimization using the k-splittable variant, a variant where each job is allowed to be split into most formula_8 different machines. They show that this variant and another more general variant where each job has its own splitability parameter, are NP-hard. They give some approximation algorithms, but their main result is a polynomial-time algorithm for both problems, for a fixed number of machines. They show that allowing a bounded number of splittings reduces the complexity of scheduling.\nIn all these works, there is no global bound on the number of splitting jobs.", "Engineering,_Manufacturing": 0.9996747971, "qwen": "Yes"}
{"id": "47096542", "revid": "42921602", "url": "https://en.wikipedia.org/wiki?curid=47096542", "title": "Takaoka plant", "text": "The Toyota Takaoka Assembly Plant, also known as Takaoka Plant, was built in Toyota City, Aichi, Japan in 1966 to build the first Toyota Corolla (series KE10). Production officially began January 1967 where production was transferred from the Toyota Motomachi plant.\nThe location continues to build the Corolla, and was the manufacturing location for past and current models that included the Toyota Publica, Toyota Sprinter, Toyota Carina, Toyota Tercel, Toyota Cynos and the Toyota Prius. Its current size is and employs 3,150 people. This number of employees is from December 2011, and excludes fixed-term employees and short-term employees.\nIt also serves as a support location for various Toyota assembly locations internationally. ", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "41599694", "revid": "19244234", "url": "https://en.wikipedia.org/wiki?curid=41599694", "title": "Programming station", "text": "A programming station is a terminal or computer that allows a machine operator to control a machine remotely, rather than being on the factory or shop floor. The programming station usually provides all the functionality including management and diagnostics that are found on the main control station.", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "41394056", "revid": "1113647506", "url": "https://en.wikipedia.org/wiki?curid=41394056", "title": "Slag (welding)", "text": "Welding slag is a form of slag, or vitreous material produced as a byproduct of some arc welding processes, most specifically shielded metal arc welding (also known as stick welding), submerged arc welding, and flux-cored arc welding. Slag is formed when flux, the solid shielding material used in the welding process, melts in or on top of the weld zone (also known as Dross). Slag is the solidified remaining flux after the weld area cools.\nFlux.\nWelding flux is a combination of carbonate and silicate materials used in welding processes to shield the weld from atmospheric gases. When the heat of the weld zone reaches the flux, the flux melts and outgasses. The gases produced push the atmospheric gas back, preventing oxidation (and reactions with nitrogen).\nThe melted flux covers the molten metal in the weld zone. Flux materials are chosen so that the density of the melted flux / slag is lower than that of the metal being welded, so that the flux floats to the very top of the weld puddle and leaves pure or nearly pure metal to solidify below.\nFlux materials may also contribute to metal behavior in the molten metal, with physical or chemical alterations to the molten metal.\nThe flux cover also helps thermally insulate the weld and reduce the cooling rate.\nInclusions.\nIt is possible for areas of slag to become embedded within the solidified metal, if it did not float to the top of the molten metal for some reason. These are called inclusions and are a form of welding defect. Inclusions may be visible on the surface after cleaning, or may be completely contained within the metal, in that case they can only be detected on X-rays of the weld, requiring grinding or drilling to remove (followed by re-welding that section).\nProcesses.\nFour welding processes use flux in slag-producing manners:\nRemoval of slag.\nSlag does not contribute to strength or protection of metals after the welding process; it is waste material. Removal of the slag is necessary for four reasons: \nRemoval is usually done using manual or power tools. Manual tools may include a welding or chipping hammer, which has a pointed tip on one end to break up large chunks of slag efficiently, or wire brushes. Power tools include angle grinders with grinder disks or wire brush wheels.", "Engineering,_Manufacturing": 1.0000063181, "qwen": "Yes"}
{"id": "10059897", "revid": "41865877", "url": "https://en.wikipedia.org/wiki?curid=10059897", "title": "NSK Ltd.", "text": ", also known in some markets as NSK Automation, is a large manufacturer of bearings globally and the largest in Japan. The company produces industrial machinery bearings, precision machinery and parts, and automotive bearings and components.\nThe company is listed on the Tokyo Stock Exchange, is a component of the Nikkei 225 stock index, and has over 144 overseas operations in 29 countries.\nPresent day business.\n30,577 employees form a worldwide technology network consisting of over 65 production plants in 14 countries. Approximately three million new bearings are manufactured per day (from miniature bearings with a one-millimetre bore to bearings with a diameter of five meters).", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "763693", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=763693", "title": "Laser engraving", "text": "Laser engraving is the practice of using lasers to engrave an object. Laser marking, on the other hand, is a broader category of methods to leave marks on an object, which in some cases, also includes color change due to chemical/molecular alteration, charring, foaming, melting, ablation, and more. The technique does not involve the use of inks, nor does it involve tool bits which contact the engraving surface and wear out, giving it an advantage over alternative engraving or marking technologies where inks or bit heads have to be replaced regularly.\nThe impact of laser marking has been more pronounced for specially designed \"laserable\" materials and also for some paints. These include laser-sensitive polymers and novel metal alloys.\nThe term laser marking is also used as a generic term covering a broad spectrum of surfacing techniques including printing, hot-branding and laser bonding. The machines for laser engraving and laser marking are the same, so that the two terms are sometimes confused by those without knowledge or experience in the practice.\nLaser engraving mechanisms.\nLaser engraving is the process of selectively removing microscopic layers of material, thus creating visible marks on the treated surface. Depending on the materials, the laser-material interactions can be different. On harder surfaces, the mechanism of action is primarily the ablation where the focused beam of laser dislodges microscopic particles from the substrate. Engraving can achieve depth of 100μm and beyond, whereas laser marking is typically shallower.\nThe choice of lasers is important for the quality of the mark. To create a clean mark, short bursts of high quality laser pulses are preferable, since they are able to transfer large amounts of energy without causing significant heating and melting of the sample.\nLaser engraving machines.\nA laser engraving machine consists of three main parts: a laser, a controller, and a surface. The laser is a drawing tool: the beam emitted from it allows the controller to trace patterns onto the surface. The controller determines the direction, intensity, speed of movement, and spread of the laser beam aimed at the surface. The surface is chosen to match the type of material the laser can act on.\nThere are three main genres of engraving machines. The most common is the X–Y table where, usually, the workpiece (surface) is stationary and the laser optics move around in two dimensions, directing the laser beam to draw vectors. Sometimes the laser is stationary and the workpiece moves. Sometimes the workpiece moves in one axis and the laser in the other. A second genre is for cylindrical workpieces (or flat workpieces mounted around a cylinder) where the laser effectively traverses a fine helix while on–off laser pulsing produces the desired raster image. In the third genre, both the laser and workpiece are stationary and galvo mirrors move the laser beam over the workpiece surface. Laser engravers using this technology can work in either raster or vector mode.\nThe point where the laser beam touches the surface should be on the focal plane of the laser's optical system and is usually synonymous with its focal point. This point is typically small, perhaps less than a fraction of a millimetre (depending on the optical wavelength). Only the area inside this focal point is significantly affected when the laser beam passes over the surface. The energy delivered by the laser changes the surface of the material at the focal point. It may heat up the surface and subsequently the material, or perhaps the material may fracture (known as \"glassing\" or \"glassing up\") and flake off the surface. Cutting through the paint of a metal part is generally how material is laser engraved.\nIf the surface material is vaporised during laser engraving, ventilation through the use of blowers or a vacuum pump are almost always required to remove the noxious fumes and smoke arising from this process, and for removal of debris on the surface to allow the laser to continue engraving.\nA laser can remove material very efficiently because the laser beam can be designed to deliver energy to the surface in a manner which converts a high percentage of the light energy into heat. The beam is highly focused and collimated—in most non-reflective materials like wood, plastics and enamel surfaces, the conversion of light energy to heat is more than {x%} efficient. However, because of this efficiency, the equipment used in laser engraving may heat up rather quickly. Elaborate cooling systems are required for the laser. Alternatively, the laser beam may be pulsed to decrease the amount of excessive heating.\nDifferent patterns can be engraved by programming the controller to traverse a particular path for the laser beam over time. The \"trace\" of the laser beam is carefully regulated to achieve a consistent removal depth of material. For example, criss-crossed paths are avoided to ensure that each etched surface is exposed to the laser only once, so the same amount of material is removed. The speed at which the beam moves across the material is also considered in creating engraving patterns. Changing the intensity and spread of the beam allows more flexibility in the design. For example, by changing the proportion of time (known as \"duty-cycle\") the laser is turned on during each pulse, the power delivered to the engraving surface can be controlled appropriately for the material.\nSince the position of the laser is known exactly by the controller, it is not necessary to add barriers to the surface to prevent the laser from deviating from the prescribed engraving pattern. As a result, no resistive mask is needed in laser engraving. This is primarily why this technique is different from older engraving methods.\nA good example of where laser engraving technology has been adopted into the industry norm is the production line. In this particular setup, the laser beam is directed towards a rotating or vibrating mirror. The mirror moves in a manner which may trace out numbers and letters onto the surface being marked. This is particularly useful for printing dates, expiry codes, and lot numbering of products travelling along a production line. Laser marking allows materials made of plastic and glass to be marked \"on the move\". The location where the marking takes place is called a \"marking laser station\", an entity often found in packaging and bottling plants. Older, slower technologies such as hot stamping and pad printing have largely been phased out and replaced with laser engraving.\nFor more precise and visually decorative engravings, a \"laser table\" (also known as an \"X–Y\" or \"XY\" table) is used. The laser is usually fixed permanently to the side of the table and emits light towards a pair of movable mirrors so that every point of the table surface can be swept by the laser. At the point of engraving, the laser beam is focused through a lens at the engraving surface, allowing very precise and intricate patterns to be traced out.\nA typical setup of a laser table involves the fixed laser emitting light parallel to one axis of the table aimed at a mirror mounted on the end of an adjustable rail. The beam reflects off the mirror angled at 45 degrees so that the laser travels a path exactly along the length of the rail. This beam is then reflected by another mirror mounted to a movable trolley which directs the beam perpendicular to the original axis. In this scheme, two degrees of freedom (one vertical, and one horizontal) for etching can be represented.\nIn other laser engraving devices such as \"flat table\" or \"drum engraving\", the laser beam is controlled to direct most of its energy a fixed penetration depth into the material to be engraved. In this manner, only a particular depth of material is removed when the engraving takes place. A simple machined stick or angle-iron can be used as a tool to help trained technologists adjust the engraver to achieve the required focusing. This setup is preferred for surfaces which do not vary in height appreciably.\nFor surfaces that vary in height, more elaborate focusing mechanisms have been developed. Some are known as \"dynamic auto focus systems\". They adjust the lasing parameters in real time to adapt to the changes to the material as it is being etched. Typically, the height and depth of the surface are monitored with devices tracking changes to ultrasound, infrared, or visible light aimed at the engraving surface. These devices, known as \"pilot beams\" or \"pilot lasers\" (if a laser is used) help guide the adjustments made to the lens of the laser in determining the optimal spot to focus on the surface and remove material effectively.\n\"X–Y\" laser engraving machines may operate in vector and raster mode.\nVector engraving follows the line and curve of the pattern to be engraved, much like a pen-based plotter draws by constructing line segments from a description of the outlines of a pattern. Much early engraving of signs and plaques (laser or otherwise) used pre-stored font outlines so that letters, numbers or even logos could be scaled to size and reproduced with exactly defined strokes. Unfortunately, \"fill\" areas were problematic, as cross-hatching patterns and dot-fills sometimes exhibited moiré effects or uber-patterns caused by the imprecise calculation of dot spacings. Moreover, rotations of a font or dynamic scaling often were beyond the capabilities of the font-rendering device. The introduction of the PostScript page-description language now allows much greater flexibility—now virtually anything that can be described in vectors by PostScript-enabled software like CorelDRAW or Adobe Illustrator can be outlined, filled with suitable patterns, and laser-engraved.\nRaster engraving traces the laser across the surface in a back-and-forth slowly advancing linear pattern that will remind one of the printhead on an inkjet or similar printer. The pattern is usually optimized by the controller/computer so that areas to either side of the pattern which aren't to be engraved are ignored and the trace across the material is thus shortened for better efficiency. The amount of advance of each line is normally less than the actual dot-size of the laser; the engraved lines overlap just slightly to create a continuity of engravure. As is true of all rasterized devices, curves and diagonals can sometimes suffer if the length or position of the raster lines varies even slightly in relation to the adjacent raster scan; therefore exact positioning and repeatability are critically important to the design of the machine. The advantage of rasterizing is the near effortless \"fill\" it produces. Most images to be engraved are bold letters or have large continuously engraved areas, and these are well-rasterized. Photos are rasterized (as in printing), with dots larger than that of the laser's spot, and these also are best engraved as a raster image. Almost any page-layout software can be used to feed a raster driver for an X–Y or drum laser engraver. While traditional sign and plaque engraving tended to favour the solid strokes of vectors out of necessity, modern shops tend to run their laser engravers mostly in raster mode, reserving vector for a traditional outline \"look\" or for speedily marking outlines or \"hatches\" where a plate is to be cut.\nMaterials that can be engraved.\nNatural materials.\nThe marking of organic materials like wood is based on material carbonisation which produces darkening of the surface and marks with high contrast. Directly \"burning\" images on wood were some of the first uses of engraving lasers. The laser power required here is often less than 10 watts depending on the laser being used as most are different. Hardwoods like walnut, mahogany and maple produce good results. Softwoods can be judiciously engraved but tend to vaporise at less-consistent depths. Marking softwood requires the lowest power levels and enables the fastest cut speeds, while active cooling (e.g. a fan with sufficient airflow) inhibits ignition. Hard papers and fiberboard work well; linty papers and newsprint are like softwoods. Fur is not engraveable; finished leathers though can be laser-engraved with a look very similar to hot-branding. Certain latex rubber compounds can be laser engraved; for example these can be used to fabricate inking-stamps.\nPaper masking tape is sometimes used as a pre-engraving overcoat on finished and resiny woods so that cleanup is a matter of picking the tape off and out of the unengraved areas, which is easier than removing the sticky and smoky surround \"halos\" (and requires no varnish-removing chemicals).\nPlastics.\nEach plastic has specific material properties, especially the light absorption spectrum. The laser irradiation can generate direct chemical modifications, melting or evaporation of the material. Plastics are rarely seen in their pure state because several additives are used such as colorants, ultraviolet retardants, release agents, etc. These additives impact the result of laser marking.\nStandard cast acrylic plastic, acrylic plastic sheet, and other cast resins generally laser very well. A commonly engraved award is a cast acrylic shape designed to be lasered from the back side. Styrene (as in compact disc cases) and many of the thermoforming plastics will tend to melt around the edge of the engraving spot. The result is usually \"soft\" and has no \"etch\" contrast. The surface may actually deform or \"ripple\" at the lip areas. In some applications this is acceptable; for example date markings on 2-litre soda bottles do not need to be sharp.\nFor signage and face plates, etc., special laser-marked plastics were developed. These incorporate silicate or other materials which conduct excess heat away from the material before it can deform. Outer laminates of this material vaporise easily to expose different coloured material below.\nOther plastics may be successfully engraved, but orderly experimentation on a sample piece is recommended. Bakelite is said to be easily laser-engraved; some hard engineering plastics work well. Expanded plastics, foams and vinyls, however, are generally candidates for routing rather than laser engraving. Plastics with a chlorine content (such as vinyl, PVC) produce corrosive chlorine gas when lasered, which combines with Hydrogen in the air to produce vaporised hydrochloric acid which can damage a laser engraving system. Urethane and silicone plastics usually don't work well—unless it is a formulation filled with cellulose, stone or some other stable insulator material.\nMany light switchplates from companies such as Leviton or Lutron can be laser engraved. Again, experimentation may be necessary to develop the correct laser settings to result in engraving the surface rather than melting it. Often the laser engraving is followed by backfilling with paint on the engraved surface to produce more contrast between the engraved surface and the surrounding surface.\nKevlar can be laser-engraved and laser-cut. However, Kevlar does give off extremely hazardous fumes (cyanide gas) when it is vaporised.\nMetals.\nMetals are heat resistant and thermally conductive, making them more difficult to engrave than other materials. Due to their thermal conductivity, pulsed, rather than continuous wave lasers, are preferred in laser engraving applications. High peak power, low pulse duration lasers are able to ablate material off a metal engraving surface without delivering enough energy to melt the surface.\nThe best traditional engraving materials started out being the worst laser-engravable materials. This problem has now been solved using lasers at shorter wavelength than the traditional 10,640 nm wavelength CO2 laser. Using Yb:Fiber Lasers, Nd:YVO4 or at 1,064 nm wavelength, or its harmonics at 532 and 355 nm, metals can now easily be engraved using commercial systems.\nCoated metals.\nThe same conduction that works against the spot vaporisation of metal is an asset if the objective is to vaporise some other coating away from the metal. Laser engraving metal plates are manufactured with a finely polished metal, coated with an enamel paint made to be \"burned off\". At levels of 10 to 30 watts, excellent engravings are made as the enamel is removed quite cleanly. Much laser engraving is sold as exposed brass or silver-coated steel lettering on a black or dark-enamelled background. A wide variety of finishes are now available, including screen-printed marble effects on the enamel.\nAnodized aluminum is commonly engraved or etched with laser machines. With power less than 40W this metal can easily be engraved with clean, impressive detail. The laser bleaches the color exposing the white or silver aluminum substrate. Although it comes in various colors, laser engraving black anodized aluminum provides the best contrast of all colors. Unlike most materials engraving anodize aluminum does not leave any smoke or residue.\nSpray coatings can be obtained for the specific use of laser engraving metals, these sprays apply a coating that is visible to the laser light which fuses the coating to the substrate where the laser passed over. Typically, these sprays can also be used to engrave other optically invisible or reflective substances such as glass and are available in a variety of colours. Besides spray coatings, some laser-markable metals come pre-coated for imaging. Products such as this transform the surface of the metal to a different color (often black, brown or grey).\nStone and glass.\nStone and glass do not vaporise or melt easily. As a result, this makes them generally a better candidate for other means of engraving, most notably sandblasting or cutting using diamonds and water. But when a laser hits glass or stone, something else interesting happens: it fractures. Pores in the surface expose natural grains and crystalline \"stubs\" which, when heated very quickly, can separate a microscopic sized \"chip\" from the surface because the hot piece is expanding relative to its surroundings. \nSo lasers are indeed used to engrave on glass, and if the power, speed and focus are just right, excellent results can be achieved. One should avoid large \"fill\" areas in glass engraving because the results across an expanse tend to be uneven; the glass ablation simply cannot be depended on for visual consistency, which may be a disadvantage or an advantage depending on the circumstances and the desired effect. As of 2021, recent advances in UV Laser technology now supply 10W (or greater) of UV lasing energy and produce significantly better engraving results on glass than prior, lower powered iterations of UV laser marking systems (i.e. 3W) or classic laser marking systems. The newer UV systems engrave cleanly and clearly without a high degree of micro-fracturing on the mark surface. Since modern 10W UV laser systems heat the surrounding substrate less than other laser marking systems, glass substrates are significantly less prone to fracturing from the laser marking process. High quality fill engravings on thin glass and crystal substrates are now regularly reproducible at high-volume in full production environments.\nJewelry.\nThe demand for personalized jewelry has made jewellers more aware of the benefits of the laser engraving process.\nJewellers found that by using a laser, they could tackle an engraving task with greater precision. In fact, jewellers discovered that laser engraving allowed for more precision than other types of engraving. At the same time, jewellers discovered that laser applied engravings had a number of other desirable features. These features include the customization, personalization, and sheer beauty of these engravings.\nAt one time jewellers who attempted to do laser engraving did need to use large pieces of equipment. Now the devices that perform laser engraving come in units. Some entrepreneurs have placed such units in mall kiosks. That has made laser engraving jewelers much more accessible. The makers of machines for laser engraving jewellers have developed some very specialized equipment. They have designed machines that can engrave the inside of a ring. They have also created machines that have the ability to engrave the back of a watch.\nA laser can cut into both flat and curved surfaces such as the surfaces on jewelry. That points out the reason why jewellers have welcomed all the adaptations for the creation of laser engraved jewelry.\nFine art.\nLaser engraving can also be used to create works of fine art. Generally, this involves engraving into planar surfaces, to reveal lower levels of the surface or to create grooves and striations which can be filled with inks, glazes, or other materials. Some laser engravers have rotary attachments which can engrave around an object. Artists may digitize drawings, scan or create images on a computer, and engrave the image onto any of the materials cited in this article.\nTrophies, Plaques and Awards.\nThe relatively low cost of laser engraving, driven by automation and inexpensive materials, makes it an ideal solution for personalization of trophies and awards. Whereas hand engraving may be a viable solution for more expensive champion’s trophies, laser customization lends itself to team and participation trophies which are often ordered in quantity and carry relatively low margins.\nMany also prefer the legibility afforded by a laser, which often delivers a crisper appearance than other methods at a much lower cost. \nLaserable materials, whether plastic or FlexiBrass, are available in a variety of colors, adding to the popularity of laser personalization for trophies and plaques. The two most popular combinations are gold lettering on a black background and black lettering on a gold background. While the same color combinations are common for plaques as well, the variety of colors used in plaque engraving is more varied.\nLaser etched mirrors.\nAs with regular etched mirrors, the initial focus of laser engraving machines was to etch an image onto the glass surface of the mirror. When power, focus and speed are optimized, similar results to sandblasting or chemical etching can be achieved.\nIn a new form of mirror engraving the laser pulsates through the reflective silver layer at the rear of the mirror. As a result, the glass side of a laser engraved mirror remains intact, maintaining the full reflective qualities of the original mirror.\nAfter the engraving process in finished, the rear of the mirror needs to be \"filled\" with a new coating to bring out the lasered detail. When a photograph or text is laser engraved, a rear coating of solid black will lend monochromatic images the greatest definition. Coloured coatings can supply chromaticity.\nIndustrial applications.\nDirect laser engraving of flexographic plates and cylinders.\nDirect laser engraving of flexographic printing cylinders and plates has been an established process since the 1970s. This first began with the use of a carbon dioxide laser used to selectively ablate or evaporate a variety of rubber plate and sleeve materials to produce a print-ready surface without the use of photography or chemicals. With this process there is no integral ablation mask as with direct photopolymer laser imaging (discussed below). Instead a high-power carbon dioxide laser head burns away, or ablates, unwanted material. The aim is to form sharp relief images with steep first relief and contoured shoulder supported edges to give a high-standard of process color reproduction. A short water wash and dry cycle follows, which is less complex than in the post-processing stages for direct laser imaging or conventional flexo platemaking using photopolymer plates. After engraving, the photopolymer is exposed through the imaged black layer and washed out in the traditional photopolymer process requiring photography and chemicals (as discussed in the next section).\nBefore the year 2000, lasers only produced lower-quality results in rubber-like materials due to their rough structure. In the 2000s, fiber lasers were introduced, giving a much-increased engraving quality directly into black polymeric materials. At the Drupa 2004, the direct engraving of polymer plates was introduced. This had also an effect on the rubber developers who, in order to stay competitive, developed new high quality rubber-like materials. The development of suitable polymeric compounds has also allowed the engraving quality achievable with the fiber lasers to be realized in print. Since then, direct laser engraving of flexo-printing forms is seen by many as the modern way to make printing forms for it is the first truly digital method.\nAs a competitive process, more recent laser systems have been introduced to selectively engrave the thin opaque black layer of a specially produced photopolymer plate or sleeve.\nDirect photopolymer laser imaging.\nClosely related is the direct imaging of a digital flexo plates or sleeves \"in the round\" on a fast-rotating drum or cylinder. This is carried out on a platesetter integrated within a digital prepress workflow that also supports digital proofing. Again, this is a filmless process, which removes one of the variables in obtaining the fine and sharp dots for screened effects, including process color printing.\nWith this process, the electronically generated image is scanned at speed to a photopolymer plate material that carries a thin black mask layer on the surface. The infrared laser-imaging head, which runs parallel to the drum axis, ablates the integral mask to reveal the uncured polymer underneath. A main ultraviolet exposure follows to form the image through the mask. The remaining black layer absorbs the ultraviolet radiation, which polymerizes the underlying photopolymer where the black layer has been removed. The exposed digital plate still needs to be processed like a conventional flexo plate. That is, using solvent-based washout with the necessary waste recovery techniques, although some water-washable digital plates are in development. This technology has been used since 1995 and is only now becoming more widely used around the world as more affordable equipment becomes available. Trade sources say there are around 650 digital platesetters installed in label, packaging and trade platemaking houses.\nLaser engraving of anilox rolls.\nPrior to 1980 anilox rolls were produced by a variety of mechanical processes. These metal anilox rolls were sometimes sprayed with ceramic to prolong their life in the flexographic printing press. During the 1980s laser engraving systems were produced which used a carbon dioxide laser to engrave the required cell pattern directly into the polished ceramic surface. Since then Q-switched YAG lasers were used for a period as they provided a more focusable laser beam as well as increased pulsing frequencies capable of engraving the finer cell configuration demanded by the ever-evolving flexographic printing process. Since approximately the year 2000 the direct anilox laser engraving process has been dominated by the use of fibre lasers which provide the high powers of the carbon dioxide lasers together with the finely focusable beam of the YAG lasers. Optical systems providing the rapid switching of multiple beams have allowed the fibre laser system to be dominant in this market. This technology has become known as Multi-Beam-Anilox or MBA.\nSub-surface laser engraving (SSLE).\nSub-surface laser engraving is the process of engraving an image in a transparent solid material by focusing a laser below the surface to create small fractures. Such engraved materials are of high-grade optical quality (suitable for lenses, with low dispersion) to minimize distortion of the beam. BK7 glass is a common material for this application. Plastics are also used, but with far less desirable results when compared to the engraving done in optical crystal.\nSince its commercial application in the late 1990s, SSLE has become more cost-effective with a number of different sized machines ranging from small (~US$35,000–60,000) to large production-scale tables (>US$250,000). Although these machines are becoming more available, it is estimated that only a few hundred are in operation worldwide. Many machines require very expensive cooling, maintenance and calibration for proper use. The more popular SSLE engraving machines use the Diode Pumped Solid State or DPSS laser process. The laser diode, the primary component which excites a pulsed solid state laser, can easily cost one third of the machine itself and functions for a limited number of hours, although a good quality diode can last thousands of hours.\nSince 2009, use of SSLE has become more cost effective to produce 3D images in souvenir 'crystal' or promotional items with only a few designers concentrating on designs incorporating large or monolithic sized crystal. A number of companies offer custom-made souvenirs by taking 3D pictures or photos and engraving them into the crystal.", "Engineering,_Manufacturing": 0.9999091625, "qwen": "Yes"}
{"id": "1197767", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1197767", "title": "Thermal interface material", "text": "A thermal interface material (often abbreviated as TIM) is any material that is inserted between two components in order to enhance the thermal coupling between them. A common use is heat dissipation, in which the TIM is inserted between a heat-producing device (e.g. an integrated circuit) and a heat-dissipating device (e.g. a heat sink). At each interface, a thermal resistance exists and impedes heat dissipation. In addition, the electronic performance and device lifetime can degrade dramatically under continuous overheating and large thermal stress at the interfaces. Therefore, there have been intensive efforts to develop improved TIMs, with the aim of minimizing the thermal boundary resistance between layers and enhancing thermal management performance, as well as tackling application requirements such as low thermal stress between materials of different thermal expansion coefficients, low elastic modulus or viscosity, flexibility, and reusability. Popularly used categories of TIMs include:", "Engineering,_Manufacturing": 0.9952782989, "qwen": "Yes"}
{"id": "28022710", "revid": "10678181", "url": "https://en.wikipedia.org/wiki?curid=28022710", "title": "2006–07 UEFA Cup qualifying rounds", "text": "This article details the 2006–07 UEFA Cup qualifying rounds.\nTimes are CEST , as listed by UEFA (local times, if different, are in parentheses).\nRound and draw dates.\nAll draws held at UEFA headquarters in Nyon, Switzerland.\nMatches may also be played on Tuesdays or Wednesdays instead of the regular Thursdays due to scheduling conflicts.\nTeams.\nBelow are the 100 teams involved in the qualifying rounds, grouped by their starting rounds. The 32 winners of the second qualifying round qualified for the first round.\nFirst qualifying round.\nSummary.\n!colspan=\"5\"|Southern-Mediterranean region\n!colspan=\"5\"|Central-East region\n!colspan=\"5\"|Northern region\nMatches.\n\"Tirana won 3–1 on aggregate.\"\n\"CSKA Sofia won 5–1 on aggregate.\"\n\"Litex Lovech won 6–0 on aggregate.\"\n\"Sarajevo won 5–0 on aggregate.\"\n\"Domžale won 7–0 on aggregate.\"\n\"Dinamo București won 9–1 on aggregate.\"\n\"APOEL won 7–1 on aggregate.\"\n\"Omonia won 4–3 on aggregate.\"\n\"Lokomotiv Sofia won 3–1 on aggregate.\"\n\"Roeselare won 7–2 on aggregate.\"\n\"Rapid București won 6–0 on aggregate.\"\n\"Vaduz won 4–1 on aggregate.\"\n\"Zimbru Chișinău won 3–2 on aggregate.\"\n\"Young Boys won 4–1 on aggregate.\"\n\"2–2 on aggregate; Videoton won on away goals.\"\n\"1–1 on aggregate; Dinamo Minsk won on away goals.\"\n\"Karvan won 2–0 on aggregate.\"\n\"2–2 on aggregate; Ameri won on away goals.\"\n\"BATE won 3–0 on aggregate.\"\n\"Basel won 3–1 on aggregate.\"\n\"Artmedia won 3–2 on aggregate.\"\n\"Drogheda United won 4–2 on aggregate.\"\n\"Brøndby won 3–1 on aggregate.\"\n\"Llanelli won 2–1 on aggregate.\"\n\"Skonto won 5–0 on aggregate.\"\n\"Åtvidaberg won 7–0 on aggregate.\"\n\"Ventspils won 4–1 on aggregate.\"\n\"Brann won 2–0 on aggregate.\"\n\"2–2 on aggregate; Randers won on away goals.\"\n\"Kaunas won 4–1 on aggregate.\"\n\"Sūduva won 2–1 on aggregate.\"\n\"Levadia Tallinn won 2–1 on aggregate.\"\n\"Start won 4–0 on aggregate.\"\n\"1–1 on aggregate; Flora Tallinn won on away goals.\"\n\"Derry City won 2–0 on aggregate.\"\nSecond qualifying round.\nSummary.\n!colspan=\"5\"|Southern-Mediterranean region\n!colspan=\"5\"|Central-East region\n!colspan=\"5\"|Northern region\nMatches.\n\"Trabzonspor won 2–1 on aggregate.\"\n\"Hapoel Tel Aviv won 4–2 on aggregate.\"\n\"1–1 on aggregate; CSKA Sofia won on away goals.\"\n\"Ethnikos Achna won 6–2 on aggregate.\"\n\"Auxerre won 5–2 on aggregate.\"\n\"Dinamo București won 2–1 on aggregate.\"\n\"Partizan won 3–2 on aggregate.\"\n\"Rapid București won 2–1 on aggregate.\"\n\"Lokomotiv Sofia won 6–0 on aggregate.\"\n\"Litex Lovech won 2–1 on aggregate.\"\n\"Kayserispor won 5–1 on aggregate.\"\n\"Artmedia won 5–3 on aggregate.\"\n\"Sion won 1–0 on aggregate.\"\n\"Grasshoppers won 3–1 on aggregate.\"\n\"Slavia Prague won 2–0 on aggregate.\"\n\"1–1 on aggregate; Chornomorets Odesa won on away goals.\"\n\"2–2 on aggregate; Basel won on away goals.\"\n\"Metalurh Zaporizhya won 3–0 on aggregate.\"\n\"Wisła Kraków won 2–1 on aggregate.\"\n\"Hertha BSC won 3–2 on aggregate.\"\n\"Rubin Kazan won 5–0 on aggregate.\"\n\"3–3 on aggregate; Marseille won on away goals.\"\n\"1–1 on aggregate; Start won 11–10 on penalties\"\n\"Odense won 6–1 on aggregate.\"\n\"Randers won 3–2 on aggregate.\"\n\"Levadia Tallinn won 2–1 on aggregate.\"\n\"Newcastle United won 1–0 on aggregate.\"\n\"4–4 on aggregate; Åtvidaberg won on away goals.\"\n\"Molde won 2–1 on aggregate.\"\n\"Brøndby won 4–0 on aggregate.\"\n\"Club Brugge won 7–2 on aggregate.\"\n\"Derry City won 7–3 on aggregate.\"", "Engineering,_Manufacturing": 0.9999394417, "qwen": "Yes"}
{"id": "28026756", "revid": "1574590", "url": "https://en.wikipedia.org/wiki?curid=28026756", "title": "Rolled throughput yield", "text": "Rolled throughput yield (RTY) in production economics is the probability that a process with more than one step will produce a defect free unit. It is the product of yields for each process step of the entire process. \nFor any process, it is ideal for that process to produce its product without defects and without rework. Rolled throughput yield quantifies the cumulative effects of inefficiencies found throughout the process. Rolled throughput yield and rolled throughput yield loss (RTYL) are often used in Six Sigma.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "28034290", "revid": "125972", "url": "https://en.wikipedia.org/wiki?curid=28034290", "title": "Vibratory stress relief", "text": "Vibratory Stress Relief, often abbreviated VSR, is a non-thermal stress relief method used by the metal working industry to enhance the dimensional stability and mechanical integrity of castings, forgings, and welded components, chiefly for two categories of these metal workpieces:\nThis stress is called \"residual stress\", because it remains in a solid material after the original cause of the stress has been removed. Residual stresses can occur through a variety of mechanisms including inelastic (plastic) deformations, temperature gradients (during thermal cycle), or structural changes (phase transformation). For example, heat from welding may cause localized expansion, which is taken up during welding by either the molten metal or the placement of parts being welded. When the finished weldment cools, some areas cool and contract more than others, leaving residual stresses. These stresses often lead to distortion or warping of the structure during machining, assembly, testing, transport, field-use or over time. In extreme cases, residual stress can cause structural failure.\nAlmost all vibratory stress relief equipment manufacturers and procedures use the workpiece's own resonant frequency to boost the loading experienced by induced vibration, so to maximize the degree of stress relief achieved. Some equipment and procedures are designed to operate near, but not at, workpiece resonances (perhaps to extend equipment life) example WIAP research, but independent research has consistently shown resonant frequency vibration to be more effective. \"See references 4, 6, and 9.\"\nThe effectiveness of vibratory stress relief is highly questionable. In general, the strain amplitudes achieved during vibratory stress relief are too low to exceed the critical stress required to activate mechanical relaxation during the induced low amplitude high cycle fatigue excitation of the transducer vibrations. If the strain amplitudes were increased to a level sufficient to cause instability in the residual stresses, fatigue damage would occur. For most applications, conventional stress relief methodologies should be applied to components that require the reduction of residual stresses.\nCriteria for effective VSR treatment.\nEffective vibratory stress relief treatment results from a combination of factors:\nEach of these changes, which often combine, i.e., peak growth AND shifting, is consistent with a lowering of the rigidity of the workpiece. The workpiece rigidity is inflated by the presence of residual stress. In the example below, which depicts a common resonance pattern change that occurs during vibratory stress relief, the large peak grew by 47%, while simultaneously shifting to the left 28-RPM, which is less than 0.75%. \"See Figure 4.\"\nThe equipment used to perform this stress relief had vibrator speed regulation of ± 0.02%, and speed increment fine-tuning of 1-RPM, which allowed even subtle shifting of the peaks to be accurately tracked to their final, stable locale.\nThe pattern of change, i.e., how quickly the peaks grow and shift, is faster at the beginning of vibration treatment: As treatment continues, the rate of change decreases, eventually resulting in a new, stable resonance pattern. Stability of this new resonance pattern indicates that dimensional stability of the workpiece has been achieved.\nThe power plot is useful in both positioning and orienting the vibrator, and when adjusting the vibrator unbalance. Poor or inappropriate vibrator locations or orientations, or excessive vibrator unbalance settings, cause large peaks in the power plot. Use of higher-powered vibrator motors (above 2-kW) provides more \"head-room\" for peaks in power to be tolerated, and treatment to take place, which was the case here: The power peak at ≈ 3700-RPM was only half of the vibrator motor's 2.3-kW power capacity (top of the power scale).\nA \"Pre-Treatment Scan\", which functions as a base-line, is first recorded in green. The operator uses this green data set to tune upon the resonances, and monitor the growth and shifting of the resonance peaks. After peak growth and shifting have subsided, a \"Post-Treatment Scan\" is made (red). This data is superimposed on the original, green, Pre-Treatment Scan data, documenting the changes in resonance pattern. The stress relief treatment resulted in 47% growth of the original, large peak, while it shifted to the left 28-RPM (less than 0.75%).\nAfter stress relief treatment, the braces (rust-colored, structural beams), which are used to maintain the desired shape during welding, were removed. The spacing between the two \"arms\" remained the same; no change was detectable (measured to 1/32\" or less than 1 mm), and the spacing remained so throughout assembly, testing (to 60 ton test loads), transport, and installation.\nWhen should VSR be considered and the limits of TSR.\nVSR is not accepted by the Engineering community at large as a viable method of relaxing or reducing residual stresses in components that require it. For general use, conventional residual stress relaxation methodologies are recommended.\nHistorically, the first type of stress relief was performed on castings by storing them outside for months or even years. This was referred to as \"curing\", a term used for long-term storage of freshly hewn wood. Fresh castings were referred to as being green, meaning, they were prone to distortion during precision machining, just as \"green\" wood bows during cutting.\nLater, thermal stress relief (TSR) was developed to alleviate the lengthy time requirements of curing. It has been known for many years, however, that TSR has limitations or shortcomings, specifically:\nMetal components, whose function would be enhanced by stress relief, and fall into one or more of the above categories, are strong candidates for VSR for quality-related reasons.\nFurther, there is a strong economic incentive to use vibratory stress relief on large workpieces, since stress relief using a furnace (thermal stress relief or TSR) is highly energy-intensive; consuming much natural gas, and hence, producing much CO2. The cost of TSR is approximately proportional to a metal component's weight or overall size, estimated to be US$2,500 for the structure pictured, plus transportation costs, which might involve special transport permits, to and from a furnace. VSR Treatment would cost a company owning appropriate equipment less than 15% as much ( ≈ $400 ) as TSR Treatment, chiefly amortization of equipment investment plus labor, and a modest amount of electrical consumption, and treatment would take less than two hours, with no transport required. However, the lack of independent data to show that this technique is effective may mean that even that lesser investment is not of any value, so use of VSR should evaluated very carefully before proceeding.\nReferences.\nPDF D. Rao, J. Ge, and L. Chen, \"Vibratory Stress Relief in the Manufacturing the Rails of a Maglev System, J. of Manufacturing Science and Engineering,\" 126, Issue 2, 388-391 (2004)\nPDF B.B. Klauba, C.M. Adams, J.T. Berry, \"Vibratory Stress Relief: Methods Used to Monitor and Document Effective Treatment, A Survey of Users, and Directions for Further Research, Proc. of ASM, 7th International Conference: Trends in Welding Research\" 601-606 (2005)\nPDF Y. Yang, G. Jung, and R. Yancey, \"Finite Element Modeling of Vibratory Stress Relief after Welding, Proc of ASM, 7th International Conference; Trends in Welding Research\" 547-552 (2005)", "Engineering,_Manufacturing": 0.9935052991, "qwen": "Yes"}
{"id": "28041875", "revid": "46172332", "url": "https://en.wikipedia.org/wiki?curid=28041875", "title": "Cellulose electrode", "text": "A cellulose electrode is a welding electrode that has a coating containing organic materials. About 30% of the coating weight is cellulose.\nIn some countries, paper pulp and wood powder are added to the coating in certain ratios to reduce the amount of pure cellulose. \nThe organic compounds in the coating decompose in the arc to form carbon monoxide, carbon dioxide and hydrogen, which increase the arc tension and thus, the welding arc becomes stronger and harder. Compared with other types of electrodes, with the same current values, a 70% deeper penetration can be obtained with cellulose electrodes.\nThis type of electrode is generally produced with thin or medium coating thicknesses. When the coating is thin, a light amount of slag is formed on the welding bead and the spatter loss is high. On the other hand, the gap filling and vertical down welding capability as well as penetration of the weld obtained by this electrode is good.\nSince this electrode can be used in every position (particularly in vertical down), it has a wide range of applications in the ship building industry and in the welding of pipelines with a wall thickness of less than 12.5 mm. The cellulose that burns during welding forms a very good protective gaseous atmosphere.\nApplication.\nThe main features of cellulose electrodes are as follows:\nThe titanium compounds in the coating provide arc stability as well as help clean the slag easily. Adding a certain amount of ferromanganese to the coating makes it possible to compensate for the manganese that is lost through oxidation during welding and to deoxidize the weld pool. Since these electrodes are generally manufactured using a sodium silicate binder, they can best be used with DC(+) polarity.", "Engineering,_Manufacturing": 0.9999922514, "qwen": "Yes"}
{"id": "63207718", "revid": "35936988", "url": "https://en.wikipedia.org/wiki?curid=63207718", "title": "Panos Kouvelis", "text": "Panos (Panagiotis) Kouvelis is the Emerson Distinguished Professor of Supply Chain, Operations, and Technology and director of \"The Boeing Center for Supply Chain Innovation\" at the Olin Business School at Washington University in St. Louis. He is best known for his work on supply chain management, supply chain finance, operational excellence, and risk management.\nEarly life and education.\nKouvelis was born in Greece. After graduating from National Technical University of Athens in 1983, he moved to the United States, where he went on to earn his MBA and MS from the Marshall School of Business at the University of Southern California. In 1988, he earned his PhD from the Management Science and Engineering department at Stanford University.\nCareer.\nKouvelis served as an assistant professor at the University of Texas at Austin from 1988 to 1991 and an associate professor at Duke University's Fuqua School of Business from 1992 to 1997. He visited Washington University in St. Louis from 1996 to 1997, where he accepted a full professor position in 1997. He was installed as the inaugural Emerson Distinguished Professor of Operations and Manufacturing Management in 2000. Kouvelis served as the senior associate dean and director of executive programs at the Olin Business School from 2009 to 2013, as well as area chair of the Operations and Manufacturing Management department from 2005 to 2009. He has accepted visiting professorships at the WHU-Otto Beisheim School of Management, the University of Chicago, and Hong Kong Polytechnic University.\nKouvelis is an editor for the journals Production & Operations Management, Manufacturing and Service Operations Management, and \"Foundations and Trends in Technology, Information and Operations Management\".\nThe Boeing Center for Supply Chain Innovation.\nKouvelis was a founding co-director of The Boeing Center for Technology, Information, and Manufacturing in 1997. He became the director of the center in 2000, and continues to direct it. The center was renamed to \"The Boeing Center for Supply Chain Innovation\". (BCSCI) in 2016.", "Engineering,_Manufacturing": 0.9999142885, "qwen": "Yes"}
{"id": "3650205", "revid": "19502098", "url": "https://en.wikipedia.org/wiki?curid=3650205", "title": "Single-machine scheduling", "text": "Single-machine scheduling or single-resource scheduling is an optimization problem in computer science and operations research. We are given \"n\" jobs \"J\"1, \"J\"2, ..., \"Jn\" of varying processing times, which need to be scheduled on a single machine, in a way that optimizes a certain objective, such as the throughput.\nSingle-machine scheduling is a special case of identical-machines scheduling, which is itself a special case of optimal job scheduling. Many problems, which are NP-hard in general, can be solved in polynomial time in the single-machine case.\nIn the standard three-field notation for optimal job scheduling problems, the single-machine variant is denoted by 1 in the first field. For example, \" 1||formula_1\" is an single-machine scheduling problem with no constraints, where the goal is to minimize the sum of completion times.\nThe makespan-minimization problem 1||formula_2, which is a common objective with multiple machines, is trivial with a single machine, since the makespan is always identical. Therefore, other objectives have been studied.\nMinimizing the sum of completion times.\nThe problem 1||formula_1 aims to minimize the sum of completion times. It can be solved optimally by the Shortest Processing Time First rule (SPT): the jobs are scheduled by ascending order of their processing time formula_4.\nThe problem 1||formula_5 aims to minimize the \"weighted\" sum of completion times. It can be solved optimally by the Weighted Shortest Processing Time First rule (WSPT): the jobs are scheduled by ascending order of the ratio formula_6.\nThe problem 1|chains|formula_5 is a generalization of the above problem for jobs with dependencies in the form of chains. It can also be solved optimally by a suitable generalization of WSPT.\nMinimizing the cost of lateness.\nThe problem 1||formula_8 aims to minimize the maximum \"lateness\". For each job \"j\", there is a due date formula_9. If it is completed after its due date, it suffers \"lateness\" defined as formula_10. 1||formula_8 can be solved optimally by the Earliest Due Date First rule (EDD): the jobs are scheduled by ascending order of their deadline formula_9.\nThe problem 1|prec|formula_13 generalizes the 1||formula_8 in two ways: first, it allows arbitrary precedence constraints on the jobs; second, it allows each job to have an arbitrary cost function \"hj\", which is a function of its completion time (lateness is a special case of a cost function). The maximum cost can be minimized by a greedy algorithm known as Lawler's algorithm.\nThe problem 1|formula_15|formula_8 generalizes 1||formula_8 by allowing each job to have a different \"release time\" by which it becomes available for processing. The presence of release times means that, in some cases, it may be optimal to leave the machine idle, in order to wait for an important job that is not released yet. Minimizing maximum lateness in this setting is NP-hard. But in practice, it can be solved using a branch-and-bound algorithm.\nMaximizing the profit of earliness.\nIn settings with deadlines, it is possible that, if the job is completed by the deadline, there is a profit \"pj\". Otherwise, there is no profit. The goal is to maximize the profit. Single-machine scheduling with deadlines is NP-hard; Sahni presents both exact exponential-time algorithms and a polynomial-time approximation algorithm.\nMaximizing the throughput.\nThe problem 1||formula_18 aims to minimize the \"number\" of late jobs, regardless of the amount of lateness. It can be solved optimally by the Hodgson-Moore algorithm. It can also be interpreted as maximizing the number of jobs that complete on time; this number is called the throughput.\nThe problem 1||formula_19 aims to minimize the \"weight\" of late jobs. It is NP-hard, since the special case in which all jobs have the same deadline (denoted by 1|formula_20|formula_19 ) is equivalent to the Knapsack problem.\nThe problem 1|formula_15|formula_18 generalizes 1||formula_18 by allowing different jobs to have different \"release times\". The problem is NP-hard. However, when all job lengths are equal, the problem can be solved in polynomial time. It has several variants:\nJobs can have \"execution intervals\". For each job \"j\", there is a processing time \"tj\" and a start-time \"sj\", so it must be executed in the interval [\"sj,\" \"sj+tj\"]. Since some of the intervals overlap, not all jobs can be completed. The goal is to maximize the number of completed jobs, that is, the throughput. More generally, each job may have several possible intervals, and each interval may be associated with a different profit. The goal is to choose at most one interval for each job, such that the total profit is maximized. For more details, see the page on interval scheduling.\nMore generally, jobs can have \"time-windows\", with both start-times and deadlines, which may be larger than the job length. Each job can be scheduled anywhere within its time-window. Bar-Noy, Bar-Yehuda, Freund, Naor and Schieber present a (1-\"ε\")/2 approximation.\nSee also.\nMany solution techniques have been applied to solving single machine scheduling problems. Some of them are listed below.", "Engineering,_Manufacturing": 0.9961053729, "qwen": "Yes"}
{"id": "35953518", "revid": "45302443", "url": "https://en.wikipedia.org/wiki?curid=35953518", "title": "Domínguez & Cía", "text": "Domínguez & Cía (BVC: DOM) is a Venezuelan company based in Caracas, founded in 1930. It is a manufacturer of plastic containers, aluminium and tin cans, and cardboard packaging.", "Engineering,_Manufacturing": 0.9999041557, "qwen": "Yes"}
{"id": "35959520", "revid": "57939", "url": "https://en.wikipedia.org/wiki?curid=35959520", "title": "Expandable microsphere", "text": "Expandable microspheres are microscopic spheres comprising a thermoplastic shell encapsulating a low boiling point liquid hydrocarbon. When heated to a temperature high enough to soften the thermoplastic shell, the increasing pressure of the hydrocarbon will cause the microsphere to expand. The volume can increase by 60 to 80 times.\nExpandable microsphere.\nThe expandable microsphere is a material that can act as a blowing agent when mixed in a product and subsequently heated to cause expansion within the matrix.\nThe expandable microspheres are off-white, can be 6 to 40 micrometers in average diameter and have a density of 900 to 1400 kg/m3.\nThe expandable microspheres are used as a blowing agent in products like e.g. puff ink, automotive underbody coatings or injection molding of thermoplastics. Here the product must be heated at some point in the process for the expandable microspheres to expand.\nExpanded microsphere.\nThe expanded microsphere is a material that has been heated to cause expansion. The product acts as a light weight filler in many products.\nThe expanded microspheres are white, can be 15 to 90 micrometers in average diameter and can have a density of 15 to 70 kg/m3.\nThe expanded microspheres are used as a lightweight filler in composite materials such as cultured marble, in waterborne paints and crack fillers/joint compound.\nCharacteristics.\nCharacteristics that make expandable microspheres unique,", "Engineering,_Manufacturing": 0.9999521971, "qwen": "Yes"}
{"id": "28942", "revid": "35854622", "url": "https://en.wikipedia.org/wiki?curid=28942", "title": "Solder", "text": "Solder (; NA: ) is a fusible metal alloy used to create a permanent bond between metal workpieces. Solder is melted in order to wet the parts of the joint, where it adheres to and connects the pieces after cooling. Metals or alloys suitable for use as solder should have a lower melting point than the pieces to be joined. The solder should also be resistant to oxidative and corrosive effects that would degrade the joint over time. Solder used in making electrical connections also needs to have favorable electrical characteristics.\nSoft solder typically has a melting point range of , and is commonly used in electronics, plumbing, and sheet metal work. Alloys that melt between are the most commonly used. Soldering performed using alloys with a melting point above is called \"hard soldering\", \"silver soldering\", or brazing.\nIn specific proportions, some alloys are eutectic — that is, the alloy's melting point is the lowest possible for a mixture of those components, and coincides with the freezing point. Non-eutectic alloys can have markedly different \"solidus\" and \"liquidus\" temperatures, as they have distinct liquid and solid transitions. Non-eutectic mixtures often exist as a paste of solid particles in a melted matrix of the lower-melting phase as they approach high enough temperatures. In electrical work, if the joint is disturbed while in this \"pasty\" state before it fully solidifies, a poor electrical connection may result; use of eutectic solder reduces this problem. The pasty state of a non-eutectic solder can be exploited in plumbing, as it allows molding of the solder during cooling, e.g. for ensuring watertight joint of pipes, resulting in a so-called \"wiped joint\".\nFor electrical and electronics work, solder wire is available in a range of thicknesses for hand-soldering (manual soldering is performed using a soldering iron or soldering gun), and with cores containing flux. It is also available as a room temperature paste, as a preformed foil shaped to match the workpiece which may be more suited for mechanized mass-production, or in small \"tabs\" that can be wrapped around the joint and melted with a flame where an iron isn't usable or available, as for instance in field repairs. Alloys of lead and tin were commonly used in the past and are still available; they are particularly convenient for hand-soldering. Lead-free solders have been increasing in use due to regulatory requirements plus the health and environmental benefits of avoiding lead-based electronic components. They are almost exclusively used today in consumer electronics.\nPlumbers often use bars of solder, much thicker than the wire used for electrical applications, and apply flux separately; many plumbing-suitable soldering fluxes are too corrosive (or conductive) to be used in electrical or electronic work. Jewelers often use solder in thin sheets, which they cut into snippets.\nEtymology.\nThe word solder comes from the Middle English word , via Old French and , from the Latin , meaning \"to make solid\".\nComposition.\nLead-based.\nTin-lead (Sn-Pb) solders, also called \"soft solders\", are commercially available with tin concentrations between 5% and 70% by weight. The greater the tin concentration, the greater the solder's tensile and shear strengths. Lead mitigates the formation of tin whiskers, though the precise mechanism for this is unknown. Today, many techniques are used to mitigate the problem, including changes to the annealing process (heating and cooling), addition of elements like copper and nickel, and the application of conformal coatings. Alloys commonly used for electrical soldering are 60/40 Sn-Pb, which melts at , and 63/37 Sn-Pb used principally in electrical/electronic work. The latter mixture is a eutectic alloy of these metals, which:\nIn the United States, since 1974, lead is prohibited in solder and flux in plumbing applications for drinking water use, per the Safe Drinking Water Act. Historically, a higher proportion of lead was used, commonly 50/50. This had the advantage of making the alloy solidify more slowly. With the pipes being physically fitted together before soldering, the solder could be wiped over the joint to ensure water tightness. Although lead water pipes were displaced by copper when the significance of lead poisoning began to be fully appreciated, lead solder was still used until the 1980s because it was thought that the amount of lead that could leach into water from the solder was negligible from a properly soldered joint. The electrochemical couple of copper and lead promotes corrosion of the lead and tin. Tin, however, is protected by insoluble oxide. Since even small amounts of lead have been found detrimental to health as a potent neurotoxin, lead in plumbing solder was replaced by silver (food-grade applications) or antimony, with copper often added, and the proportion of tin was increased (see lead-free solder).\nThe addition of tin—more expensive than lead—improves wetting properties of the alloy; lead itself has poor wetting characteristics. High-tin tin-lead alloys have limited use as the workability range can be provided by a cheaper high-lead alloy.\nLead-tin solders readily dissolve gold plating and form brittle intermetallics.\n60/40 Sn-Pb solder oxidizes on the surface, forming a complex 4-layer structure: tin(IV) oxide on the surface, below it a layer of tin(II) oxide with finely dispersed lead, followed by a layer of tin(II) oxide with finely dispersed tin and lead, and the solder alloy itself underneath.\nLead, and to some degree tin, as used in solder contains small but significant amounts of radioisotope impurities. Radioisotopes undergoing alpha decay are a concern due to their tendency to cause soft errors. Polonium-210 is especially troublesome; lead-210 beta decays to bismuth-210 which then beta decays to polonium-210, an intense emitter of alpha particles. Uranium-238 and thorium-232 are other significant contaminants of alloys of lead.\nLead-free.\nThe European Union Waste Electrical and Electronic Equipment Directive and Restriction of Hazardous Substances Directive were adopted in early 2003 and came into effect on July 1, 2006, restricting the inclusion of lead in most consumer electronics sold in the EU, and having a broad effect on consumer electronics sold worldwide. In the US, manufacturers may receive tax benefits by reducing the use of lead-based solder. Lead-free solders in commercial use may contain tin, copper, silver, bismuth, indium, zinc, antimony, and traces of other metals. Most lead-free replacements for conventional 60/40 and 63/37 Sn-Pb solder have melting points from 50 to 200 °C higher, though there are also solders with much lower melting points. Lead-free solder typically requires around 2% flux by mass for adequate wetting ability.\nWhen lead-free solder is used in wave soldering, a slightly modified solder pot may be desirable (e.g. titanium liners or impellers) to reduce maintenance cost due to increased tin-scavenging of high-tin solder.\nLead-free solder is prohibited in critical applications, such as aerospace, military and medical projects, because joints are likely to suffer from metal fatigue failure under stress (such as that from thermal expansion and contraction). Although this is a property that conventional leaded solder possess (like any metal), the point at which stress fatigue can possibly occur is substantially above the level of stresses normally encountered. Lead free solder, by contrast, will always fail eventually regardless of how low a level of stress is encountered.\nTin-silver-copper (Sn-Ag-Cu, or \"SAC\") solders are used by two-thirds of Japanese manufacturers for reflow and wave soldering, and by about 75% of companies for hand soldering. The widespread use of this popular lead-free solder alloy family is based on the reduced melting point of the Sn-Ag-Cu ternary eutectic behavior , which is below the 22/78 Sn-Ag (wt.%) eutectic of and the 99.3/0.7 Sn-Cu eutectic of . The ternary eutectic behavior of Sn-Ag-Cu and its application for electronics assembly was discovered (and patented) by a team of researchers from Ames Laboratory, Iowa State University, and from Sandia National Laboratories-Albuquerque.\nMuch recent research has focused on the addition of a fourth element to Sn-Ag-Cu solder, in order to provide compatibility for the reduced cooling rate of solder sphere reflow for assembly of ball grid arrays. Examples of these four-element compositions are 18/64/14/4 tin-silver-copper-zinc (Sn-Ag-Cu-Zn) (melting range 217–220 °C) and 18/64/16/2 tin-silver-copper-manganese (Sn-Ag-Cu-Mn; melting range of 211–215 °C).\nTin-based solders readily dissolve gold, forming brittle intermetallic joins; for Sn-Pb alloys the critical concentration of gold to embrittle the joint is about 4%. Indium-rich solders (usually indium-lead) are more suitable for soldering thicker gold layer as the dissolution rate of gold in indium is much slower. Tin-rich solders also readily dissolve silver; for soldering silver metallization or surfaces, alloys with addition of silvers are suitable; tin-free alloys are also a choice, though their wettability is poorer. If the soldering time is long enough to form the intermetallics, the tin surface of a joint soldered to gold is very dull.\nHard solder.\nHard solders are used for brazing, and melt at higher temperatures. Alloys of copper with either zinc or silver are the most common.\nIn silversmithing or jewelry making, special hard solders are used that will pass assay. They contain a high proportion of the metal being soldered and lead is not used in these alloys. These solders vary in hardness, designated as \"enameling\", \"hard\", \"medium\" and \"easy\". Enameling solder has a high melting point, close to that of the material itself, to prevent the joint desoldering during firing in the enameling process. The remaining solder types are used in decreasing order of hardness during the process of making an item, to prevent a previously soldered seam or joint desoldering while additional sites are soldered. Easy solder is also often used for repair work for the same reason. Flux is also used to prevent joints from desoldering.\nSilver solder is also used in manufacturing to join metal parts that cannot be welded. The alloys used for these purposes contain a high proportion of silver (up to 40%), and may also contain cadmium.\nAlloys.\nDifferent elements serve different roles in the solder alloy:\nImpurities.\nImpurities usually enter the solder reservoir by dissolving the metals present in the assemblies being soldered. Dissolving of process equipment is not common as the materials are usually chosen to be insoluble in solder.\nBoard finishes vs wave soldering bath impurities buildup:\nFlux.\nFlux is a reducing agent designed to help reduce (return oxidized metals to their metallic state) metal oxides at the points of contact to improve the electrical connection and mechanical strength. The two principal types of flux are acid flux (sometimes called \"active flux\"), containing strong acids, used for metal mending and plumbing, and rosin flux (sometimes called \"passive flux\"), used in electronics. Rosin flux comes in a variety of \"activities\", corresponding roughly to the speed and effectiveness of the organic acid components of the rosin in dissolving metallic surface oxides, and consequently the corrosiveness of the flux residue.\nDue to concerns over atmospheric pollution and hazardous waste disposal, the electronics industry has been gradually shifting from rosin flux to water-soluble flux, which can be removed with deionized water and detergent, instead of hydrocarbon solvents. Water-soluble fluxes are generally more conductive than traditionally used electrical / electronic fluxes and so have more potential for electrically interacting with a circuit; in general it is important to remove their traces after soldering. Some rosin type flux traces likewise should be removed, and for the same reason.\nIn contrast to using traditional bars or coiled wires of all-metal solder and manually applying flux to the parts being joined, much hand soldering since the mid-20th century has used flux-core solder. This is manufactured as a coiled wire of solder, with one or more continuous bodies of inorganic acid or rosin flux embedded lengthwise inside it. As the solder melts onto the joint, it frees the flux and releases that on it as well.\nOperation.\nThe solidifying behavior depends on the alloy composition. Pure metals solidify at a certain temperature, forming crystals of one phase. Eutectic alloys also solidify at a single temperature, all components precipitating simultaneously in so-called coupled growth. Non-eutectic compositions on cooling start to first precipitate the non-eutectic phase; dendrites when it is a metal, large crystals when it is an intermetallic compound. Such a mixture of solid particles in a molten eutectic is referred to as a mushy state. Even a relatively small proportion of solids in the liquid can dramatically lower its fluidity.\nThe temperature of total solidification is the solidus of the alloy, the temperature at which all components are molten is the liquidus.\nThe mushy state is desired where a degree of plasticity is beneficial for creating the joint, allowing filling larger gaps or being wiped over the joint (e.g. when soldering pipes). In hand soldering of electronics it may be detrimental as the joint may appear solidified while it is not yet. Premature handling of such joint then disrupts its internal structure and leads to compromised mechanical integrity.\nIntermetallics.\nMany different intermetallic compounds are formed during solidifying of solders and during their reactions with the soldered surfaces. The intermetallics form distinct phases, usually as inclusions in a ductile solid solution matrix, but also can form the matrix itself with metal inclusions or form crystalline matter with different intermetallics. Intermetallics are often hard and brittle. Finely distributed intermetallics in a ductile matrix yield a hard alloy while coarse structure gives a softer alloy. A range of intermetallics often forms between the metal and the solder, with increasing proportion of the metal; e.g. forming a structure of . Layers of intermetallics can form between the solder and the soldered material. These layers may cause mechanical reliability weakening and brittleness, increased electrical resistance, or electromigration and formation of voids. The gold-tin intermetallics layer is responsible for poor mechanical reliability of tin-soldered gold-plated surfaces where the gold plating did not completely dissolve in the solder.\nTwo processes play a role in a solder joint formation: interaction between the substrate and molten solder, and solid-state growth of intermetallic compounds. The base metal dissolves in the molten solder in an amount depending on its solubility in the solder. The active constituent of the solder reacts with the base metal with a rate dependent on the solubility of the active constituents in the base metal. The solid-state reactions are more complex – the formation of intermetallics can be inhibited by changing the composition of the base metal or the solder alloy, or by using a suitable barrier layer to inhibit diffusion of the metals.\nSome example interactions include:\nPreform.\nA preform is a pre-made shape of solder specially designed for the application where it is to be used. Many methods are used to manufacture the solder preform, stamping being the most common. The solder preform may include the solder flux needed for the soldering process. This can be an internal flux, inside the solder preform, or external, with the solder preform coated.\nSimilar substances.\nGlass solder is used to join glasses to other glasses, ceramics, metals, semiconductors, mica, and other materials, in a process called glass frit bonding. The glass solder has to flow and wet the soldered surfaces well below the temperature where deformation or degradation of either of the joined materials or nearby structures (e.g., metallization layers on chips or ceramic substrates) occurs. The usual temperature of achieving flowing and wetting is between .", "Engineering,_Manufacturing": 0.9998828173, "qwen": "Yes"}
{"id": "56436080", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=56436080", "title": "Spin welding of polymers", "text": "Spin welding is a form of friction welding used to join thermoplastic parts. The parts to be welded must be round, and in plane with each other. Like all other welding methods this process utilizes heat, time, and pressure to create a weld joint. Heat is generated via internal friction generated between the two parts when rotating and subjected to a load normal to the weld joint. This frictional heat causes the plastic to melt and a bond to be created.\nDue to this process's high speeds, and high repeat ability it is favored for a high production environment. This process was initially used to weld plastic compasses under a liquid to allow the internal parts of the compass to be filled with the liquid, but it is used in a very wide range of industries and applications.\nSpin welding equipment.\nSpin welding machines come in two different types an inertia welding machine, and a continuous drive machine. In general, one of the parts to be welded is clamped in place, while the other is rotated. Spin welding machines consist of two tool fixtures; fixed tooling, and a driven tooling.\nTooling.\nThe tooling in the spin welding machine provides support for the materials being joined while under heat and pressure. Tooling can be made of metal, such as aluminum, or epoxy molding compounds depending on how the tooling will be used. Guards may be incorporated into the tooling to prevent molten material or parts from being ejected.\nLower tooling.\nThe lower tooling, sometimes referred to as the \"nest\", supports one of the parts to be welded. The part is usually placed in the nest with the walls supporting the component as close to the joint as possible to prevent distortion of the part during joining.\nUpper tooling.\nDepending on the design of the machine, the upper tooling may hold a part to be joined or simply apply the necessary pressure and impart rotation to one of the parts being joined. For parts that held in place by the upper tooling prior to the start of welding, press fitting the part will prevent dropping prior to welding. Drive pins, serrations, or a grit blasted finish may be used to help the upper tooling impart rotational force on the part.\nInertia welding machines.\nInertia welding machines use a motor to spin the parts to a set RPM, and then disengages the motor and relies on the internal friction of the parts to slow down the machine again. The inertial energy contained in the machine's flywheel is transferred to the weld interface through the parts. There are also two different designs for inertia welding machines. One such design disengages the clamped part, and allows the whole part to rotate until slowing to a stop, while another allows the parts to continue to rotate until cooling and solidification stops the rotation.\nContinuous drive welding machines.\nContinuous drive machines operate under the same principle of using a motor to spin the part up to a user determined RPM, but instead of disengaging the drive when welding begins it continues to spin the part through the whole welding cycle. The rotation is stopped via a mechanical braking system that halts the machine either gradually or instantly, this depends on the system.\nProcess steps.\nThis section outlines the overall steps of the spin welding process. This is a description of what is might be observed in a production setting when using the spin welding process.\nPart preparation and loading.\nNormally parts are loaded into a holding fixture. The parts may be placed in the base of the welding machine or for larger assemblies, one half may be placed in the upper fixture of the welding machine. This process can be accomplished in 2 to 5 seconds when manually loading parts\nPress actuation.\nThe drive motors are activated, and begin to spin The speed of the drive motors can vary, based on the application, from 200 to 14,000 rpm, with a normal speed of 2,000 rpm. The drives then engage the part to be welded. This step normally only takes 1 to 2 seconds.\nWelding.\nThe welding step consists of four main sub-steps which describe how the heat generated from friction melts the parts at their interface. These steps can be described as follows:\nPhase 1.\nFriction between parts begins due to rotation from motor and the downward pressure. Heat is generated until the glass transition temperature, for amorphous polymers or the melting temperature, for semicrystalline polymers, is reached.\nPhase 2.\nPart melting begins; material is melted and part of the melted material is extruded into the \"flash\".\nPhase 3.\nA steady state is reached between the melt layer and the amount of material squeezed into the flash. The spinning is then stopped.\nPhase 4.\nWhile the joint cools, the parts are held in contact with each other, under pressure. This ensures a solid mating at the joint while the molten material cools.\nPhases 1 through 3 are usually completed in 0.5 to 2 seconds, with an additional 1 to 2 seconds required for Phase 4.\nPart removal.\nAfter weld solidification, parts are removed and any required post processing is conducted to remove the flash. Step 4 normally takes 2 to 5 seconds to complete.\nJoint design.\nWhen designing a weld joint, multiple factors are considered. Some examples of those factors include: desired weld strength, geometry of the parts, material being welded, cosmetic of the joint, whether post processing is an option or not. It is important to balance all of these factors to achieve the optimal final part.\nIn spin welding the most consistent variable is that at least one of the parts needs to be circular for this process to be effective. The simplest joint design in most processes, spin welding included, is a butt joint. This can be used when final part flash is acceptable, this is because there will always be internal flash as well as external flash. A separate process will need to be conducted to remove said flash, and often time the internal flash will be impossible to remove. Due to this, alternative geometries can be used that incorporate flash traps.\nOther joints often utilize self-centering geometries such as angled faces, which act as pre-weld sites, and also increase the overall welding area of the joint. Also of note is the fact that when using this form of weld joint a flash trap will be difficult to utilize.\nHeat generation.\nSpin welding utilizes internal heat generation which is created from friction between the two parts being welded. In its simplest form spin welding utilizes three input parameters to vary the welding process. These three parameters can be varied to change the heat generation rate as well. Parameters include: weld RPM, weld pressure, and weld time. Alternatively, other factors such as cooing time, displacement, and braking speed are possible parameters that can be altered depending on the system.\nWelding time.\nWelding time is defined as how long the parts are rotated while in contact. While welding time does not directly affect the overall heat generation rate, it is an influential factor on how much overall heat is generated throughout the welding process. Usually when utilizing this process there is a threshold time that is necessary to reach a steady state for heat generation. This steady state is defined by when the amount of material melted is equal to the amount of material expelled by the welding pressure. To achieve a quality weld this steady state must be reached for a uniform melt layer.\nWeld rotations per minute (RPM).\nThe most influential factor when trying to increase heat generation or generation rate is the welding RPM. Several experiments have been conducted, and in general the higher the RPM of the part the more heat that will be generated. This combined with welding time will help to determine the overall heat generated in the weld.\nGenerally, rotation speeds can be varied between 200-14000 RPM depending on the part and application. RPM is the main input parameter to determine heat generation in the part.\nWhen using an inertia spin welding consideration must also be given to the run up time in order to ensure that the drive head is operating at the proper speed prior to engaging the parts.\nWhen using direct-drive spin welding an optimum RPM should be chosen based on the optimal linear speed of the materials being joined. The required RPM can be calculated using the following equation:\nformula_1\nWeld pressure.\nPressure also plays a role in heat generation, it is normally a secondary parameter. In general, the higher the pressure the more heat that is generated during welding. This is due to the increase in friction by increasing contact between the parts, this falls off when the pressures become so high that the parts are unable to rotate. [Thermoplastic welding will normally use weld pressures between 72.5 psi and 290 psi.\nWelding pressure is a parameter determined by the size and area of the part being welded, larger parts require higher pressures to reach the required amount of part upset.\nMathematical analysis of heat generation.\nDuring the spin welding process there are two main phases for heat generation. The initial phase, or the solid phase is when the bulk of the heating in the part is caused by the two solid parts rubbing against one another. The heat generation can be modeled by the following:\nformula_2\nWhere q is the heat generation rate, f is the coefficient of friction, r is the radius of the parts being welded, and ω is related to rpm by the following:\nformula_3\nWhere Ω is the RPM of the parts being welded.\nThe Second phase of heat generation is phase 3 of the weld, or the steady-state phase. This is the phase of the process where there is a constant film of molten plastic at the interphase, and viscous heating is dominant. The heat generation can be modeled by the following:\nformula_4\nWhere is the viscosity of the molten polymer, r is the part radius, ω is related to the RPM as above, and 2h is the thickness of the melt layer.\nMaterials.\nThe spin welding process can adequately join almost all thermoplastic polymers. Typical with friction welding applications, higher melting temperature materials will require more energy to melt, so they will require more welding time or higher RPMs. Common additives and filler will often alter the weldability of polymers. These additions can make the weld process more difficult, or change the intended properties of the weld.\nA note on composite materials, fiber reinforced for example. The reinforcement material will not cross the weld joint, so the intended bulk material properties will vary drastically in the welded region.\nA list showing the weldability of common materials is shown below:\nApplications.\nSpin welding creates a clean and sound weld joint that requires little post processing. Due to this most parts being welded are in the final stages of production, or are in final assembly.\nThe first known application of spin welding was in the assembly of compasses, however spin welding has become used in a wide variety of products. These products include but are not limited to fuel filters, check valves, truck lights, aerosol cylinders, and floats, as well as some structural components, piping, tanks, and containers.", "Engineering,_Manufacturing": 1.0000085831, "qwen": "Yes"}
{"id": "11443297", "revid": "7912021", "url": "https://en.wikipedia.org/wiki?curid=11443297", "title": "Shear force", "text": "In solid mechanics, shearing forces are unaligned forces acting on one part of a body in a specific direction, and another part of the body in the opposite direction. When the forces are collinear (aligned with each other), they are called tension forces and compression forces. William A. Nash defines shear force in terms of planes: \"If a plane is passed through a body, a force acting along this plane is called a \"shear force\" or \"shearing force\".\"\nForce required to shear steel.\nThis section calculates the force required to cut a piece of material with a shearing action. The relevant information is the area of the material being sheared, ie the area across which the shearing action takes place, and the shear strength of the material. A round bar of steel is used as an example. The shear strength is calculated from the tensile strength using a factor which relates the two strengths. In this case 0.6 applies to the example steel, known as EN8 bright, although it can vary from 0.58–0.62 depending on application.\nEN8 bright has a tensile strength of 800MPa and mild steel, for comparison, has a tensile strength of 400MPa.\nTo calculate the force to shear a 25 mm diameter bar of EN8 bright steel;\nWhen working with a riveted or tensioned bolted joint, the strength comes from friction between the materials bolted together. Bolts are correctly torqued to maintain the friction. The shear force only becomes relevant when the bolts are not torqued.\nA bolt with property class 12.9 has a tensile strength of 1200MPa (1MPa = 1N/mm2) or 1.2kN/mm2 and the yield strength is 0.90 times tensile strength, 1080MPa in this case.\nA bolt with property class 4.6 has a tensile strength of 400MPa (1MPa = 1N/mm2) or 0.4 kN/mm2 and yield strength is 0.60 times tensile strength, 240MPa in this case.", "Engineering,_Manufacturing": 0.9999898672, "qwen": "Yes"}
{"id": "11450801", "revid": "42522270", "url": "https://en.wikipedia.org/wiki?curid=11450801", "title": "CONWIP", "text": "CONWIP (CONstant work in process) are pull-oriented production control systems. Such systems can be classified as pull and push systems (Spearman et al. 1990). In a push system, the production order is scheduled, and the material is pushed into the production line. In a pull system, the start of each product assembly process is triggered by the completion of another at the end of production line. This pull-variant is known for its ease of implementation.\nCONWIP is a kind of single-stage kanban system and is also a hybrid push-pull system. While kanban systems maintain tighter control of system WIP through the individual cards at each workstation, CONWIP systems are easier to implement and adjust, since only one set of system cards is used to manage system WIP. CONWIP uses cards to control the number of WIPs. For example, no part is allowed to enter the system without a card (authority). After a finished part is completed at the last workstation, a card is transferred to the first workstation and a new part is pushed into the sequential process route. In their paper, Spearman et al. (1990) used a simulation to make a comparison among the CONWIP, kanban and push systems, and found that CONWIP systems can achieve a lower WIP level than kanban systems.\nCard control policy.\nIn a CONWIP system, a card is shared by all kinds of products. However, Duenyas (1994) proposed a dedicated card control policy in CONWIP and he stated that this policy could perform as a multiple chain closed queuing network.", "Engineering,_Manufacturing": 0.9986394644, "qwen": "Yes"}
{"id": "38739743", "revid": "829949", "url": "https://en.wikipedia.org/wiki?curid=38739743", "title": "Manufacturing Enterprise Solutions Association", "text": "Manufacturing Enterprise Solutions Association International (MESA, also known as MESA International) is a worldwide not-for-profit community of manufacturing companies, information technology hardware and software suppliers, system integrators, consulting service providers, analysts, editors, academics, and students. MESA's goal is to help member companies improve business results and production operations through application and implementation of information technology and best management practices.\nHistory.\nMESA was initially founded, in 1992, to promote Manufacturing Execution Systems, its acronym and reach was later broadened to Manufacturing Enterprise Solutions Association to include a wider scope of functions in the entire Manufacturing enterprise value chain and the integration of plant floor devices and control systems into enterprise systems and business intelligence for higher levels of automation, visibility, optimization and orchestration of manufacturing processes.\nIn 2012, MESA merged with WBF (World Batch Forum), the standards organization responsible for B2MML and BatchML.\nIn 2012, MESA also signed on with the Open O&M group. An initiative of multiple industry standards organizations to provide a harmonized set of standards for the exchange of Operations & Maintenance (O&M) data and associated context. OpenO&M is an open, collaborative, effort composed of diverse groups of relevant organizations and subject matter experts. The members of OpenO&M initiative are ISA, MESA, MIMOSA, OAGi, and the OPC Foundation. \nIn 2014, MESA International signed a Memorandum of Understanding with Open Applications Group, Inc. (OAGi) making it easier for both organizations to work together and bring value to their common set of stakeholders, and formalizes the ways in which each organization can contribute to the other's committees and working groups to bring specific expertise to key initiatives. \nIn 2016, MESA releases the first formal definition of Smart Manufacturing in its paper “Smart Manufacturing – The Landscape Explained” which explains the relations and scope of initiatives including Industrial Internet of Things, and Industrie 4.0.\nIn 2017, MESA signed an MOU with The Industrial Internet Consortium (IIC). Under the agreement, the two organizations will work together to align efforts to maximize interoperability, portability, security and privacy for the industrial Internet. Joint activities will include: identifying and sharing Industrial Internet of Things (IIoT) best practices; realizing interoperability by harmonizing architecture and other elements; collaborating on standardization; and collaboration in the areas of industrial analytics and asset performance management. .\nAlso in 2017, In an effort to promote greater understanding of Smart Manufacturing (SM) technologies, the Manufacturing Enterprise Solutions Association (MESA) International and the Clean Energy Smart Manufacturing Innovation Institute (CESMII) announce an agreement that will provide CESMII-member access to valuable education that MESA has developed. \nActivities.\nMESA members participate in and contribute to a number of activities:\nParticipants.\nMESA includes member organizations such as:\nPeople participating in MESA are typically in roles such as:\nRelated organizations.\nMESA works with a number of related organizations in its work to advance best practices for Operations and Maintenance, including:", "Engineering,_Manufacturing": 1.0000071526, "qwen": "Yes"}
{"id": "286322", "revid": "12248341", "url": "https://en.wikipedia.org/wiki?curid=286322", "title": "Crash test", "text": "A crash test is a form of destructive testing usually performed in order to ensure safe design standards in crashworthiness and crash compatibility for various modes of transportation (see automobile safety) or related systems and components.\nData collection.\nCrash tests are conducted under rigorous scientific and safety standards. Each crash test is very expensive so the maximum amount of data must be extracted from each test. Usually, this requires the use of high-speed data-acquisition, at least one triaxial accelerometer and a crash test dummy, but often includes more.\nSome organizations that conduct crash tests include Calspan, an independent test laboratory in Buffalo, NY. As a result of the capabilities and expertise at Calspan, Calspan has been awarded 5 year contracts by the National Highway Traffic Safety Administration (NHTSA) to execute for the NHTSA FMVSS No. 214, Side Impact Protection Compliance Testing, FMVSS No. 301 Fuel System Integrity, and FMVSS No. 305 Electric Powered Vehicles: Electrolyte Spillage and Electrical Shock Protection vehicle crash tests. Calspan also holds the NHTSA contracts for executing New Car Assessment Program crash tests.\nAlso, Monash University department of Civil Engineering, routinely conducts crash tests for the purposes of roadside barrier safety and design.\nCrash testing programs.\nThere are a number of crash test programs around the world dedicated to providing consumers with a source of comparitative information in relation to the safety performance of new and used vehicles. Examples of new car crash test programs include National Highway Traffic Safety Administration's NCAP, the Insurance Institute for Highway Safety, Australasian New Car Assessment Program, EuroNCAP and JapNCAP. Programs such as the Used Car Safety Ratings provide consumers information on the safety performance of vehicles based on real world crash data.\nIn 2020, EuroNCAP introduces a \"mobile progressive deformable barrier (MPDB) test\" first experimented on the Toyota Yaris.", "Engineering,_Manufacturing": 0.9997538924, "qwen": "Yes"}
{"id": "62442607", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=62442607", "title": "3D printing speed", "text": "3D printing speed measures the amount of manufactured material over a given time period (formula_1), where the unit of time is measured in Seconds, and the unit of manufactured material is typically measured in units of either kg, mm or cm3, depending on the type of additive manufacturing technique.\nThe following table compares the speeds of commercially relevant 3D printing technologies.\n3D printing speed refers to only the build stage, a subcomponent of the entire 3D printing process. However, the entire process spans from pre-processing to post-processing stages. The time required for printing a completed part from a data file (.stl or .obj) is calculated as the sum of time for the following stages: \nSpeed up.\nAdditive manufacturing technologies usually imply a trade off between the printing speed and quality. Improvements in speed of the entire 3D printing process can be grouped in the following two categories.\nSoftware improvements.\nSince the actual printing process is directly influenced by how the model is sliced, oriented, and filled, optimizing them results in shorter print time. \nOptimal Orientation. Changing the orientation of a part can be done through either the STL file or on the CAD model. Determining the optimal part orientation is a common software solution for all additive manufacturing processes. This can lead to a significant improvement in many key factors that affect the total print time. The following factors heavily depend on part orientation: \nAdaptive Slicing. Error caused by the staircase effect can be measured using several metrics, all of which refer to the difference between model surface and actual printed surface. By adaptively computing the height distribution of layers, this error can be minimized: The quality of surface increases while post-processing time decreases. The benefits of adaptive slicing depend on the proportion of the surface-to-volume ratio of the part. Efficient computation of adaptive layers is possible by analyzing the model surface over the full layer height. Several implementations are available as an open source software.\nHardware improvements.\nIncreasing the speed of printing through hardware can take the following forms, many of which are used by leading 3D printing companies. \nChallenges.\nDepending on the technology used, there are some challenges that could limit the speed of the 3D printing: \nResearch.\nAcoustic fabrication.\nInteresting features of sound waves have encouraged scientists to use it in additive manufacturing. Sound waves can form pressure fields that shape the material in the desired form in a contact-free setup. The fact that it can be applied over a large area at the same time makes it a good candidate for rapid fabrication. \nThe process starts by designing an acoustic hologram. An acoustic hologram is a mask that will direct the sound field to form the desired pattern. It can be fabricated in an additive fabrication combined with etching and nanoimprint methods. The process follows by placing silicone rubber particles in a liquid medium with photo-initiator agents. Then the acoustic mask is used to generate the desired pressure sound field to put the particle in the correct order. The next step is applying the UV light to solidify the final product.\nImproved SLA processes.\nThe speed of SLA processes is limited by:\nRapid continuous additive manufacturing by inhibition patterning\nDue to the mentioned effects, the printing speed with SLA methods is limited to a few millimeters to several centimeters per hour. To address this problem a system of two light sources is used, one for polymerization and one for inhibiting the polymerization to avoid adhesion and as a result print faster. This method allows us to speed up the process up to 200 cm/hr. Moreover, by controlling the intensity of each pixel in the setup topographical patterning can be created in a single exposure with no stage translation.\nA mixture of photo initiators and photo inhibitors is used in the setup. The absorbance spectra of two material is orthogonal this allows to control the process with the two orthogonal light sources. As the material is generated layer by layer the tray is gradually lifted and the photo inhibitors will not allow adhesion near the window.\nRapid, large-volume, thermally controlled 3D printing, using a mobile liquid interface\nAnother way to address the adhesion problem is to create a dead layer which prohibits the curing process. One method to create this dead layer is to use fluorinated oil flow. This liquid is omniphobic which means that it repels all the materials and will not stick to anything. The reason to use a flow instead of a static layer is to create a larger force against the adhesion force and also help with the cooling of the cured layer (curing generates heat).\nFast 3D printing by integrating construction kit building blocks.\nDividing an Object into smaller blocks (e.g. Lego parts) before print, can lead to 2.44x increase in speed over conventional printing method. Moreover, when the object needs to be iterated to find the optimal design it is not efficient to reprint the whole object over and over again: One solution is to print the main constant structure only once and reprint only the small changing parts with high resolution. These smaller parts are mounted onto the main structure.", "Engineering,_Manufacturing": 0.9999166727, "qwen": "Yes"}
{"id": "62443231", "revid": "7118087", "url": "https://en.wikipedia.org/wiki?curid=62443231", "title": "Multi-material 3D printing", "text": "Multi-material 3D printing is the additive manufacturing procedure of using multiple materials at the same time to fabricate an object. Similar to single material additive manufacturing it can be realised through methods such as FFF, SLA and Inkjet (material jetting) 3D printing. By expanding the design space to different materials, it establishes the possibilities of creating 3D printed objects of different color or with different material properties like elasticity or solubility. The first multi-material 3D printer Fab@Home became publicly available in 2006. The concept was quickly adopted by the industry followed by many consumer ready multi-material 3D printers.\nMulti-material 3D printing Technologies.\nFused Filament Fabrication (FFF).\nFused Filament Fabrication (also known as Fused Deposition Modeling - FDM) describes the process of continuously extruding a line of thermoplastic material to form a three dimensional model. The FFF process supports a variety of materials reaching from bio degradable ones like PLA to PETG, ABS and engineering grade materials like PEEK. This technology additionally allows for the use of flexible materials like TPU. Two possible solutions to realise a multi-material FFF 3D printer are:\nSingle Nozzle Design.\nThe single nozzle design combines the different materials before or in the melting zone of the print head such that the materials are extruded through the same nozzle. For example: The different filaments can be cut and rejoined to a single strand of a mixed filament before being fed into the melting chamber. Such a technique is implemented in the Mosaic Palette. Another example is the multi-material upgrade by Prusa3d, which is mounted on top of a single material printer to add multi material capabilities. It uses a bowden style extrusion system with an additional axis to cut and select the material. To prevent impurities inside of the object a combined melting chamber has to be cleared from the previous material before a new one can be used. Depending on the implementation, the amount of waste material produced during the printing process may be significant. In some implementations, the previous material may be used as in-fill to prevent waste, or to simultaneously print a different object in which color does not matter.\nMulti-Nozzle Design.\nThe multi-nozzle design features a separate nozzle for each material. The nozzle can either be mounted on the same print head or on independent print heads. For this approach to work the different nozzles have to be calibrated to the exact same height relative to the print surface to circumvent the interference of an inactive nozzle with the printed object. Such a design reduces the amount of waste material during the printing process significantly compared to a single nozzle design which does not use the previous material as in-fill or to print another object.\nStereolithography (SLA).\nStereolithography is the process of solidifying a photopolymer with a laser layer by layer to form a three dimensional object. To realize multi-material prints with this technology, one can use multiple reservoirs for different photopolymers. A major problem with this approach is the removal of the not yet polymerised material as the print may contain cavities filled with the old material, which should be emptied before the next material can be used. The photopolymer resins used for SLA can have highly different physical properties, generally being more brittle and having a lower heat deflection temperature. The SLA standard resins come in different colours and opacities. Besides the engineering grade materials like the ABS-like or PP-like resin, there exist bio-compatible ones used for medical applications and flexible resins.\nMaterial Jetting.\nThe process of material jetting, often also called Inkjet 3D printing, is similar to the 2D Inkjet printing procedure. The print head consists of multiple small nozzles which jet droplets of photopolymers on demand. Each nozzle can extrude a different material, which allows for the creation of multi-material parts. The droplets of material are then immediately cured using a UV light source mounted to the print head. In contrast to the FFF printing process, a layer is not formed by moving the print head along a pre-calculated path, but by scanning the layer line by line. The Statasys J750, for example, allows for full colour prints. The materials supported by the material jetting printing process are similar to the ones of the SLA process and hence share similar properties. Additionally there have been advances in the field of material jetting metals by suspending nano metal particles in a fluid. After the removal of the support material the printed object has to be sintered to create a final metal part.\nBinder Jetting.\nA binder jetting 3D printer uses particles of a fine-grained powder, which are fused together using a binder, to form a three-dimensional object. In principle, it consists out of two separate chambers: One functions as a reservoir for the powdered material, the other one as the printing chamber. To fabricate a layer of an object a blade pushes the material out of the reservoir and spreads it over the printing surface to create a thin layer of powder. A print head similar to the one found in a 2D inkjet printer then applies the binder to the layer to solidify and bind it to the previous one. Although binder jetting does not allow for multi-material support, there exist printers, which feature a second print head to apply pigment to the layer after the binder to allow for full color prints.\nWorkflow.\nDesigning.\nDesigning a three dimensional object is the first step in the workflow of 3D printing. This design process can be supported by software. Such CAD software is capable of creating, managing and manipulating different 3D geometric figures while giving the user feedback through a graphical interface. Most CAD programs already support the annotation of a geometric figure with a material. The combination of different geometries then forms a single multiple material object. However, not all file formats support the annotation of materials together with the geometry of the object.\nSlicing.\nSlicing is the process of splitting a 3D model into layers to transform them into a sequence of G-Code instructions. These instructions can be processed by a 3D printer to manufacture the corresponding model in either a bottom-up, top-down or even left to right manner. Before generating the instructions, support structures can be added to connect overhanging sections of the model to either the printing surface or other parts of the model. The support structures have to be removed in a post processing step after the print has finished.\nThe slicing process for multi-material prints differs depending on the hardware used. For FFF based machines, instructions for changing the material have to be added. This comes with multiple computational challenges such as handling two print heads at the same time without them interfering with each other or clearing the melting chamber from the previous material. For SLA based multi-material prints the slicing software has to handle the additional degrees of freedom arising from the possibility of moving the print from one resin tray to the next one. The slicing procedure for material jetting printers involves the generation of multiple bitmap images representing the voxels of the object.\nPost-Processing.\n3D printed objects may need to be post processed before they can be used as a prototype or a finished product. Such post-processing steps may including sanding the surface of the object to make it smoother or painting it to match the colours of the design. Depending on the printing method and the objects geometry, support structures may have to be removed. The use of multi-material 3D printing reduces the amount of post processing needed for the same result, as colours can be printed directly. Furthermore, it is possible to use a water soluble material for printing the support structures, as their removal only involves placing the object into a water bath.\nApplications.\nFood 3D Printing.\nThe rising trend of food 3D printing supports the customisation of shape, colour, flavour, texture and nutrition of different meals. Multi-material 3D printing enables using multiple ingredients like peanut butter, jelly or dough in the printing process, which is essential for the creation of most foods. \nMedical Applications.\nMulti-material 3D printing technology is often used in the production of 3D printed prosthetics. It enables the use of different materials like a soft TPU on the contact points with the body and a stiff carbon fibre material for the corpus of the prosthetics. The prosthetics can therefore be adjusted to suit the varying needs and desires of an individual. \nAnother medical use case is the generation of artificial tissue structures. The research focuses on creating tissue, that mimics human tissue in terms of feel, elasticity and structure. Such artificial tissues can be used by surgeons to train and learn on realistic models, which is otherwise hard or expensive to achieve.\nCurrent research focuses on 3D printed drug delivery systems to efficiently deploy a medication or vaccine. Through the use of multi-material printing they create biocompatible structures that can interact with the human body on a cellular level.\nPhysical Properties.\nThe capability of switching between different materials is essential for controlling the physical properties of a 3D printed object. Besides being able to manipulate the strength of an object through micro-structures, the user can switch between harder or softer materials in the printing process to affect the rigidity of the object. Hard and soft material combination is also applied to fabricate biomimetic structure with desired properties. The use of materials of different colour or elasticity can affect the looks and the haptics of the resulting object. Additionally, it is possible to reduce the amount of post-processing needed by choosing a suitable material for the support structures or the outer hull of the part.\nRapid Prototyping.\nMulti-material 3D printing enables designers to rapidly manufacture and test their prototypes. The use of multiple materials in a single part enables the designer to create functional and visually appealing prototypes. An example of how 3D printing can be included in the design process is automotive design. There, it is necessary to quickly test and verify a prototype to get the design approved for production. The reduced post-processing steps induced by the multi-material 3D printing technology result in a shorter fabrication time. Additionally, multi-material 3D printing reduces the part count of the produced prototypes compared to traditional fabrication methods like milling or molding, because the assembly of multiple parts with different materials is no longer required.\nFile Formats.\nThere exist multiple file formats to represent three dimensional objects which are suitable for 3D printing. Yet not all of them support the definition of different materials in the same file as the geometry. The table below lists the most common file formats and their capabilities:", "Engineering,_Manufacturing": 0.9999943972, "qwen": "Yes"}
{"id": "62452729", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=62452729", "title": "3D food printing", "text": "3D food printing is the process of manufacturing food products using a variety of additive manufacturing techniques. Most commonly, food grade syringes hold the printing material, which is then deposited through a food grade nozzle layer by layer. The most advanced 3D food printers have pre-loaded recipes on board and also allow the user to remotely design their food on their computers, phones or some IoT device. The food can be customized in shape, color, texture, flavor or nutrition, which makes it very useful in various fields such as space exploration and healthcare.\nGeneral principles.\nThere are three general areas that impact precise and accurate food printing: materials/ingredients (viscosity, powder size), process parameters (nozzle diameter, printing speed, printing distance), and post-processing methods (baking, microwaving, frying).\nMaterials and ingredients.\nThe type of food available to print is limited by the printing technique. For an overview of these printing techniques, please see the section \"Printing Techniques\" below:\nExtrusion-based printing ingredients.\nCommon ingredients used in extrusion based printing are inherently soft enough to extrude from a syringe/printhead and possess a high enough viscosity to retain a shape. In certain cases, powdered ingredients (protein, sugar, etc.) are added to increase viscosity, e.g. adding flour to water creates a paste that can be printed. Inherently soft materials include:\nCertain ingredients that are solid can be used by melting and then extruding the ingredient, e.g. chocolate.\nSelective laser sintering and binder jetting ingredients.\nPowdered ingredients:\nInkjet printing ingredients.\nIngredients with low viscosity are used for surface filling:\nPrinting techniques.\nExtrusion-based printing.\nAlthough there are different approaches to extrusion based printing, these approaches follow the same basic procedures. The platform on which food is printed consists of a standard 3-axis stage with a computer controlled extrusion head. This extrusion head pushes food materials through a nozzle typically by way of compressed air or squeezing. The nozzles can vary with respect to what type of food is being extruded or the desired printing speed (typically the smaller the nozzle the longer the food printing will take). As the food is printed, the extrusion head moves along the 3-axis stage printing the desired food. Some printed food requires additional processing such as baking or frying before consumption.\nExtrusion based food printers can be purchased for household use, are typically compact in size, and have a low maintenance cost. Comparatively, extrusion based printing provides the user with more material choices. However, these food materials are usually soft, and as a result, makes printing complex food structures difficult. In addition, long fabrication times and deformations due to temperature fluctuations with additional baking or frying require further research and development to overcome.\nHot-melt and room temperature.\nIn Hot-melt extrusion, the extrusion head heats the food material slightly above the material's melting point. The melted material is then extruded from the head and then solidifies soon thereafter. This allows the material to be easily manipulated into the desired form or model. Foods such as chocolate are used in this technique because of its ability to melt and solidify quickly.\nOther food materials do not inherently require a heating element in order to be printed. Food materials such as jelly, frosting, puree, and similar food materials with appropriate viscosity can be printed at room temperature without prior melting.\nSelective laser sintering.\nIn selective laser sintering, powdered food materials are heated and bonded together forming a solid structure. This process is completed by bonding the powdered material layer by layer with a laser as the heat source. After a layer is completed with the desired areas bonded, it is then covered by a new unbonded layer of powder. Certain parts of this new unbonded layer are heated by the laser in order to bond it with the structure. This process continues in a vertical upwards manner until the desired food model is constructed. After construction, unbonded material can then be recycled and used to print another food model.\nSelective laser sintering enables the construction of complex shapes and models and the ability to create different food textures. It is limited by the range of suitable food materials, namely powdered ingredients. Due to this limitation, selective laser sintering has been used primarily for creating sweets/candies.\nBinder jetting.\nSimilarly to selective laser sintering, binder jetting uses powdered food materials to create a model layer by layer. Instead of using heat to bond the materials together, a liquid binder is used. After bonding the desired areas of a layer, a new layer of powder is then spread over the bonded layer covering it. Certain parts of this new layer are then bonded to the previous layer. The process is repeated until the desired food model is constructed.\nAs with selective laser sintering, binder jetting enables the construction of complex shapes and models and the ability to create different food textures. Likewise, it is also limited by the range of suitable food materials, namely powdered ingredients.\nInkjet printing.\nInkjet printing is used for surface filling or image decoration. By utilizing gravity, edible food ink is dropped onto the surface of the food, typically a cookie, cake, or other candy. This is a non-contact method, hence the printhead does not touch the food protecting the food from contamination during image filling. The ink droplets may consist of a broad range of colors allowing users to create unique and individualized food images. An issue with inkjet printing is the food materials being incompatible with the ink resulting in no image or high image distortion. Inkjet printers can be purchased for household or commercial use, and industrial printers are suitable for mass production.\nMulti-printhead and multi-material.\nIn multi-printhead and multi-material printing, multiple ingredients are printed at the same time or in succession. There are different ways to support multi-material printing. In one instance, multiple printheads are used to print multiple materials/ingredients, as this can speed up production, efficiency, and lead to interesting design patterns. In another instance, there is one printhead, and when a different ingredient is required, the printer exchanges the material being printed. Multiple materials/ingredients equates to a more diverse range of meals available to print, a broader nutritional range, and is quite common for food printers.\nPost-processing.\nIn the post-processing phase, printed food may require additional steps before consumption. This includes processing activities such as baking, frying, cleaning, etc. This phase can be one of the most critical to 3D printed food, as the printed food needs to be safe for consumption. An additional concern in post processing is the deformation of the printed food due to the strain of these additional processes. Current methods involve trial and error. That is, combining food additives with the materials/ingredients to improve the integrity of complex structures and to ensure the printed structure retains its shape. Additives such as transglutaminase and have been added to ingredients in order to help retain the printed shape while printing and after cooking.\nAdditionally, recent research has produced a visual simulation for baking breads, cookies, pancakes and similar materials that consist of dough or batter (mixtures of water, flour, eggs, fat, sugar and leavening agents). By adjusting certain parameters in the simulation, it shows the realistic effect that baking will have on the food. With further research and development, a visual simulation of 3D printed foods being cooked could predict what is vulnerable to deformation.\nApplications.\nPersonal nutrition.\nPersonalized dietary requirements for an individual's nutritional needs has been linked to the prevention of diseases. As such, eating nutritious food is paramount to living a healthy life. 3D printed food can provide the control necessary to put a custom amount of protein, sugar, vitamins, and minerals into the foods we consume.\nAnother area in customized food, is elderly nutrition. The elderly sometimes cannot swallow foods, and as such require a softer pallet. However, these foods are often unappealing causing some individuals not to eat what their bodies' nutritional needs require. 3D printed food can provide a soft and aesthetically pleasing food in which the elderly can consume their bodies' dietary requirements.\nIn October 2019, startup company \"Nourished\" 3D prints personalized nutritional gummies from 28 different vitamins. Individuals take a survey, then based on their answers, a personalized nutritional gummy is printed for that individual.\nSustainability and solution for hunger.\nAs the world's population continues to grow, experts believe that current food supplies will not be able to supply the population. Thus, a sustainable food source is critical. Studies have shown that entomophagy, the consumption of insects, has the potential to sustain a growing population. Insects such as crickets require less feed, less water, and provide around the same amount of protein that chickens, cows, and pigs do. Crickets can be ground into a protein flour. In one study, researchers provide an overview of the process of 3D printing insect flour into foods that do not resemble insects; thus, keeping the nutritional value of the insect intact.\nSpace exploration.\nAs humans begin venturing into space for a longer time, the nutritional requirements for maintaining crew health is critical. Currently NASA is exploring ways of integrating 3D printing food into space in order to sustain the crew's dietary requirements. The vision is to 3D print powdered food layers that have a shelf life of 30 years instead of using traditional freeze dried food that have a shelf life of 5 years. In addition to dietary requirements, 3D printing food in space could provide a morale boost, as the astronauts would be able to design custom meals that are aesthetically pleasing.\nIn September 2019, Russian cosmonauts, along with Israeli startup Aleph Farms, grew meat from cow cells, then 3D printed the cells into steaks.\nMeat bioprinting.\nLivestock farming is one of the top contributors to deforestation, land degradation, water pollution and desertification. Among other reasons, this has led to the new promising technology of meat bioprinting. One alternative to livestock farming is cultured meat, also known as lab-grown meat. Cultured meat is produced by taking a small biopsy from animals, extracting the myosatellite cells and adding growth serum to multiply the cells. The resulting product is then used as a material for bioprinting meat. The post-processing phase, among other steps, includes adding flavour, vitamins and iron to the product. Yet another alternative is printing a meat analogue. Novameat, a Spanish startup has been able to print a plant-based steak and mimic the texture and appearance of real meat.\nCreative food design.\nFood presentation and food appearance customization for individuals is a big trend in the food industry. So far food customization and creative designs have required hand-made skills, which results in low production rate and high cost. 3D food printing can overcome this problem by providing the necessary tools for creative food design even for home users. 3D food printing has enabled some intricate designs which cannot be accomplished with traditional food manufacturing. Brand logos, text, signatures, pictures can now be printed on some food products like pastries and coffee. Complex geometric shapes have also been printed, mainly using sugar. With 3D printing, chefs can now turn their visual inspirations into signature culinary creations. Another benefit is being able to print nutritious meals in shapes that appeal to children.\nReduced food waste.\nWorldwide, one third of the total food produced for consumption, around 1.6 billion tons per year, goes to waste. Food waste happens during processing, distribution and consumption. 3D food printing is a very promising way of reducing food waste during the phase of consumption, by utilizing food products like meat off-cuts, distorted fruits and vegetables, sea food by-products and perishables. These products can be processed in a suitable form for printing. Upprinting Food, a Dutch startup, has been blending and combining different ingredients from food waste to create purees which are then used as materials for 3D printing. Chefs are also creating different dishes from leftover food using 3D food printers.\nChallenges.\nStructure.\nUnlike traditionally prepared food, the variety of food that can be manufactured using 3D printing is limited by the physical characteristics of the materials. Food materials are generally much softer than the weakest plastic used in 3D printing, making the printed structures very fragile. So far, most studies use trial and error as an approach to overcoming this challenge, but scientists are working on developing new methods that are able to predict the behavior of different materials during the printing process. These methods are developed by analyzing the rheological properties of the materials and their relation to the printing stability.\nDesign.\nWhen designing a 3D model for a food product, the physical and geometrical limitations of the printing materials should be taken into account. This makes the designing process a very complex task and so far there is no available software that accounts for that. Building such software is also a complex task due to the vast variety of food materials. Considering that personal users who incorporate 3D food printing in their kitchens represent a significant part of the overall users, the design of the software interface adds to the complexity. The interface of such software should be simple and have high usability while still providing enough features and customization options for the user without causing cognitive overload.\nSpeed.\nThe current speed of 3D printing food could be sufficient for home use, but the process is very slow for mass production. Simple designs take 1 to 2 minutes, detailed designs take 3 to 7 minutes, and more intricate designs take even longer. The speed of printing food is tightly correlated to the rheological properties of the materials. Research shows that high printing speed results in low fidelity samples due to the dragging effect, while very low speed causes instability in material deposition.\nIn order for 3D food printing to find its way to the food industry, the printing speed needs improvement or the cost of such technology should be affordable enough for companies to operate several printers.\nMulti-material printing.\nThe color, flavor and texture of food are of crucial importance when fabricating an edible product, thus in most cases it is required that a food printer supports multi-material printing. The current available 3D food printers are limited to using a few different materials due to the challenge of developing multiple extruder capabilities. This limits the variety of food products that can be 3D printed, leaving out complex dishes that require a lot of different materials.\nSafety.\nWhen 3D printing food, the safety is very crucial. A food printer must ensure safety along the entire path taken by the food material. Due to the possibility of food getting stuck somewhere along the path, bacteria accumulation is a major concern. Microbial stability is a crucial parameter of the quality of the printed food, thus it needs to be addressed both during the design of the printer and during the printing process. On the other hand, the materials that come into contact with the food may not be as significant of a concern since high quality printers use stainless steel and BPA-free materials.\nCopyright.\nExisting food products in the market such as chocolates in various shapes could easily be scanned and the obtained 3D models could be used to replicate those products. These 3D models could then be disseminated via Internet leading to copyright infringement. There are laws regulating copyright issues but it is not clear whether they will be sufficient to cover all aspects of a field like 3D food printing.", "Engineering,_Manufacturing": 0.9891614914, "qwen": "Yes"}
{"id": "2576607", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=2576607", "title": "Stump gauge", "text": "A stump gauge (or wicket gauge) is an instrument used in cricket to determine the correct position for the three stumps used to form the wicket, as mandated by the Laws of Cricket. It is usually in a form of a metal (although sometimes plastic) bar with three spikes, and is used to locate and create the holes into which the spiked ends of the stumps are placed.", "Engineering,_Manufacturing": 0.9999828339, "qwen": "Yes"}
{"id": "2577767", "revid": "1041333167", "url": "https://en.wikipedia.org/wiki?curid=2577767", "title": "B-staging", "text": "B-staging is a process that utilizes heat or UV light to remove the majority of solvent from an adhesive, thereby allowing a construction to be “staged”. In between adhesive application, assembly and curing, the product can be held for a period of time, without sacrificing performance. \nAttempts to use traditional epoxies in IC packaging often created expensive production bottlenecks, because, as soon as the epoxy adhesive was applied, the components had to be assembled and cured immediately. B-staging eliminates these bottlenecks by allowing the IC manufacturing to proceed efficiently, with each step performed on larger batches of product.\nB stage laminates are also used in the electronic circuit board industry, where the laminates are reinforced with woven glass fibers called prepregs. This allows manufacturers to have clean and accurate setup for multilayer pressing of cores and prepregs for production of PCBs, without the need to hassle with liquid uncured epoxies. ", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "2920865", "revid": "22152051", "url": "https://en.wikipedia.org/wiki?curid=2920865", "title": "Twister roller coaster", "text": "A twister roller coaster is the generic name given to any roller coaster layout which tends to twist or interweave its track within itself several times. It is essentially the opposite of an Out and Back roller coaster, which is often a much more simplistic layout. Twister roller coasters often have the illusion of having small or tight clearances due to the track usually travelling through several support structures. This is known as a head chopper effect.\nTwister roller coasters were unheard of before the 1920s. John Miller is credited with inventing upstop wheels and secure lap bar restraints, both which led roller coaster designers to create wilder and twistier layouts.\nA good example of the difference between an out and back design and twister design is layouts of Apollo's Chariot and Raging Bull, two Bolliger & Mabillard designed hypercoaster roller coasters that debuted in 1999. Apollo's Chariot uses a traditional out and back layout while Raging Bull is a twister.", "Engineering,_Manufacturing": 0.9998218417, "qwen": "Yes"}
{"id": "2928212", "revid": "40610005", "url": "https://en.wikipedia.org/wiki?curid=2928212", "title": "Bauschinger effect", "text": "The Bauschinger effect refers to a property of materials where the material's stress/strain characteristics change as a result of the microscopic stress distribution of the material. For example, an increase in tensile yield strength occurs at the expense of compressive yield strength. The effect is named after German engineer Johann Bauschinger.\nWhile more tensile cold working increases the tensile yield strength, the local initial compressive yield strength after tensile cold working is actually reduced. The greater the tensile cold working, the lower the compressive yield strength.\nIt is a general phenomenon found in most polycrystalline metals. Based on the cold work structure, two types of mechanisms are generally used to explain the Bauschinger effect:\nThe net result is that the yield strength for strain in the opposite direction is less than it would be if the strain had continued in the initial direction.\nMechanism of action.\nSevere unidirectional cold working results in accumulation of dislocation at barriers to dislocation movement. When stresses are applied in the reverse direction, the dislocations are now aided by the back stresses that were present at the dislocation barriers previously and also because the back stresses at the dislocation barriers in the back are not likely to be strong compared to the previous case. Hence the dislocations glide easily, resulting in lower yield stress for plastic deformation for reversed direction of loading.\nConsequence of Bauschinger effect.\nMetal forming operations result in situations exposing the metal workpiece to stresses of reversed sign. The Bauschinger effect contributes to work softening of the workpiece, for example in straightening of drawn bars or rolled sheets, where rollers subject the workpiece to alternate bending stresses, thereby reducing the yield strength and enabling greater cold drawability of the workpiece.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "1108499", "revid": "18010125", "url": "https://en.wikipedia.org/wiki?curid=1108499", "title": "Double wishbone suspension", "text": "A double wishbone suspension is an independent suspension design for automobiles using two (occasionally parallel) wishbone-shaped arms to locate the wheel. Each wishbone or arm has two mounting points to the chassis and one joint at the knuckle. The shock absorber and coil spring mount to the wishbones to control vertical movement. Double wishbone designs allow the engineer to carefully control the motion of the wheel throughout suspension travel, controlling such parameters as camber angle, caster angle, toe pattern, roll center height, scrub radius, scuff (mechanical abrasion) and more.\nImplementation.\nThe double-wishbone suspension can also be referred to as \"double A-arms\", though the arms themselves can be A-shaped, L-shaped, or even a single bar linkage. A single wishbone or A-arm can also be used in various other suspension types, such as variations of the MacPherson strut. The upper arm is usually shorter to induce negative camber as the suspension jounces (rises), and often this arrangement is titled an \"SLA\" or \"short long arms\" suspension. When the vehicle is in a turn, body roll results in positive camber gain on the lightly loaded inside wheel, while the heavily loaded outer wheel gains negative camber.\nBetween the outboard end of the arms is a knuckle. The knuckle contains a kingpin for horizontal radial movement in older designs, and rubber or trunion bushings for vertical hinged movement. In newer designs, a ball joint at each end allow for all movement. Attached to the knuckle at its center is a bearing hub, or in many older designs, a spindle to which the wheel bearings are mounted.\nTo resist fore-aft loads such as acceleration and braking, the arms require two bushings or ball joints at the body.\nAt the knuckle end, single ball joints are typically used, in which case the steering loads have to be taken via a steering arm, and the wishbones look A- or L-shaped. An L-shaped arm is generally preferred on passenger vehicles because it allows a better compromise of handling and comfort to be tuned in. The bushing in line with the wheel can be kept relatively stiff to effectively handle cornering loads while the off-line joint can be softer to allow the wheel to recess under fore-aft impact loads. For a rear suspension, a pair of joints can be used at both ends of the arm, making them more H-shaped in plan view. Alternatively, a fixed-length driveshaft can perform the function of a wishbone as long as the shape of the other wishbone provides control of the upright. This arrangement has been successfully used in the Jaguar IRS. In elevation view, the suspension is a 4-bar link, and it is easy to work out the camber gain (see camber angle) and other parameters for a given set of bushing or ball-joint locations. The various bushings or ball joints do not have to be on horizontal axes, parallel to the vehicle centre line. If they are set at an angle, then anti-dive and anti-squat geometry can be dialled in.\nIn many racing cars, the springs and dampers are relocated inside the bodywork. The suspension uses a bellcrank to transfer the forces at the knuckle end of the suspension to the internal spring and damper. This is then known as a \"push rod\" if bump travel \"pushes\" on the rod (and subsequently the rod must be joined to the bottom of the upright and angled upward). As the wheel rises, the push rod compresses the internal spring via a pivot or pivoting system. The opposite arrangement, a \"pull rod\", will pull on the rod during bump travel, and the rod must be attached to the top of the upright, angled downward. Locating the spring and damper inboard increases the total mass of the suspension, but reduces the unsprung mass, and also allows the designer to make the suspension more aerodynamic.\nShort long arms suspension.\nA short long arms suspension (SLA) is also known as an unequal length double wishbone suspension. The upper arm is typically an A-arm, and is shorter than the lower link, which is an A-arm or an L-arm, or sometimes a pair of tension/compression arms. In the latter case the suspension can be called a multi-link, or dual ball joint suspension.\nThe four-bar linkage mechanism formed by the unequal arm lengths causes a change in the camber of the vehicle as it rolls, which helps to keep the contact patch square on the ground, increasing the ultimate cornering capacity of the vehicle. It also reduces the wear of the outer edge of the tire.\nSLAs can be classified as short spindle, in which the upper ball joint on the spindle is inside the wheel, or long spindle, in which the spindle tucks around the tire and the upper ball joint sits above the tire.\nDrawbacks.\nShort spindle SLAs tend to require stiffer bushings at the body, as the braking and cornering forces are higher. Also they tend to have poorer kingpin geometry, due to the difficulty of packaging the upper ball joint and the brakes inside the wheel.\nLong spindle SLAs tend to have better kingpin geometry, but the proximity of the spindle to the tyre restricts fitting oversized tyres, or snowchains. The location of the upper balljoint may have styling implications in the design of the sheetmetal above it.\nSLAs require some care when setting up their bump steer characteristic, as it is easy to end up with excessive, or curved, bump steer curves.\nHistory.\nThe double wishbone suspension was introduced in the 1930s. French car maker Citroën began using it in their 1934 Rosalie and Traction Avant models. Packard Motor Car Company of Detroit, Michigan, used it on the Packard One-Twenty from 1935, and advertised it as a safety feature. During that time MacPherson strut was still in the area of aviation technology and was derived from aircraft landing mechanism. Later on, until 1951, Ford Company decided to use the MacPherson strut on small production cars, the English Ford Consul and Ford Zephyr. Thus, the double wishbone was applied early in automobile history and there is no genetic relationship between MacPherson strut and double wishbone suspension.\nDouble wishbones have traditionally been considered to have superior dynamic characteristics as well as load-handling capabilities, and are therefore commonly found on sports cars and racing cars throughout automotive history. Examples of cars with double wishbone suspension include the Aston Martin DB7, the Mazda MX-5, and the third through eighth generation of the Honda Accord. Short long arms suspension, a type of double wishbone suspension, is very common on front suspensions for medium-to-large cars such as the Peugeot 407, Citroën C5, and the first two generations of the Mazda6/Atenza.\nAdvantages.\nThe double wishbone suspension provides the engineer more design choices than some other types do. It is fairly easy to work out the effect of moving each joint, so the kinematics of the suspension can be tuned easily and wheel motion can be optimized. It is also easy to work out the loads that different parts will be subjected to which allows more optimised lightweight parts to be designed. They also provide increasing negative camber gain all the way to full jounce travel, unlike the MacPherson strut, which provides negative camber gain only at the beginning of jounce travel and then reverses into positive camber gain at high jounce amounts.\nDisadvantages.\nDouble wishbone suspensions are more complex, impose more difficult packaging constraints and are thus often more expensive than other systems like a MacPherson strut. Due to the increased number of components within the suspension setup, it takes much longer to service and is heavier than an equivalent MacPherson design. At the other end of the scale, it offers less design choice than the more costly and complex multi-link suspension system.", "Engineering,_Manufacturing": 0.9999901056, "qwen": "Yes"}
{"id": "26041731", "revid": "42425010", "url": "https://en.wikipedia.org/wiki?curid=26041731", "title": "Drawbar force gauge", "text": "A drawbar force gauge is a gauge designed to measure forces on a machine tool's drawbar. These types of machines are found in metalworking, woodworking, stone cutting, and carbon fiber fabricating shops. Many modern machines generate well in excess of 50,000 N (12,000 lbf). Measuring and maintaining this force is an important and necessary part of a machine shop preventative maintenance plan.\nHow drawbar force gauges work.\nModern drawbar force gauges typically are based on a force sensor that uses bonded strain gauges and electronics to convert the resulting output into a digital display for the user to view. Earlier versions of these gauges sometimes also used a sealed hydraulic cavity with a pressure gauge to measure and display force. These hydraulic gauges are generally considered less accurate because of the physical limitations of the indicator.\nWhy drawbar force is measured.\nDrawbar force gauges allow early detection of problems with the spindle's Belleville spring stack, verification of performance of the clamping system as a whole, help prevent damage to spindle taper and other machine features critical to machining accuracy, and ultimately help to keep the machine operator safe.\nDrawbar force measurement has been made much more important in recent years with the introduction of radically higher RPM machines. These machines are necessary to work the modern materials required in a multitude of applications—new types of composite wood material, carbon fiber, and high strength materials such as titanium. High speed machining of these materials is considered to begin at 10,000 rpm and may reach as high as 50,000 rpm. The need for regular verification of the spindle clamping system becomes obvious.\nAs the required machining speeds become higher, the need for machines to be built with smaller diameter spindle components increases. When the spring pack, bearings, and hydraulic units become smaller, the stresses placed upon them become greater. As a result, the clamping system will remain in good shape for fewer and fewer \"cycles\", or \"clamp/unclamp\" procedures. Again, this requires gauges and routine procedures to monitor this process. Many operators do not realize that this is something that has changed over time.\nAny metal or wood working machine that takes advantage of the HSK taper system should be routinely checked. The slightest stroke mis-adjustment, dirt, or slight wear of the drawbar system can result in significantly reduced holding force. A preventative maintenance schedule, with a strict timetable for testing is a necessity when operating any type of high speed machine utilizing the HSK system.\nRetention knob.\nDrawbar force gauges are able to detect broken or weakening components of the drawbar clamping system, can give indications that the unit needs lubrication, detect gripper mis-adjustment, or demonstrate that the incorrect retention knob is being used for the machine. A retention knob is a device screwed into the narrow end of a tool holder, enabling the drawbar to pull the tool holder into the spindle. With a highly accurate electronic gauge, deficiencies can be noted and corrected. Many hours of expensive machine operating time can be put to use while avoiding fretting, chatter, \"stuck\" tool holders in a spindle, etc., by employing proper preventative maintenance techniques using an accurate electronic gauge and other spindle health management tools.\nDrawbar force gauges in tool holder standards.\nThe following tool holder standards specifically address tool retention force as measured by a drawbar force gauge:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "16553534", "revid": "196446", "url": "https://en.wikipedia.org/wiki?curid=16553534", "title": "Roof crush", "text": "Roof crush is the failure and displacement of an automobile roof into the passenger compartment during a rollover accident.\nEvery year approximately 10,000 Americans are killed in rollover accidents, accounting for about 30% of all light vehicle occupant fatalities. The number of occupant injuries is significantly higher. The relationship between injury levels and intrusion or roof crush has been statistically established, but the mechanism has been thought sometimes to be somewhat obscure. Theories advocating the idea that rollover injuries are caused by the occupants \"falling\" or \"diving\" into the vehicles interior have been advanced, but the severity of these events, and thus their potential for causing injury, has been questioned.\nObservations from school bus and heavy truck rollovers also suggests that the fall and dive theories are incorrect and that another theory of the mechanism of injury in rollover accidents is required, one that relates injury to the intrusion of the roof structure into the occupant compartment or more simply to \"roof crush\". Today it is generally realized that the primary injury mechanism in light vehicle rollover accidents is not crushing. Rather, it is widely acknowledged that the principal injury process for contained, i.e., non-ejected, occupants involves the impact between the occupant and the vehicle interior. Since the severity of an impact depends to a large extent on the relative velocity between the impacting objects; the impact theory of injury causation in rollovers has sought to explain the increase in injuries associated with increased roof crush with an increase in the relative velocity between the occupant and the vehicle's interior which is generated by the roof crush. In the simplest terms, when the occupants hits a collapsing roof, they hit harder because the roof is moving in on them. If the roof was not collapsing, and thus moving towards the occupants, their velocity relative to the roof would be lower and the impact less severe.\nRoof crush has also been identified as a cause of both full and partial ejection in rollover accidents because of ejection portals created by the collapsing roof structure. These chiefly involve broken windows but occasionally also involve the body structure. The current Federal regulation involving roof strength - 49 CFR 571.216 (FMVSS 216) - has been found to offer little benefit and is currently being reviewed. Many European manufacturers provide stronger roofs than do U.S. or Asian manufacturers despite the fact that there is no European (EEC) roof strength regulation for light vehicles. The Volvo XC90 may be a good example of this.", "Engineering,_Manufacturing": 0.9979882836, "qwen": "Yes"}
{"id": "24241700", "revid": "1416331", "url": "https://en.wikipedia.org/wiki?curid=24241700", "title": "2011 UEFA European Under-21 Championship qualification play-offs", "text": "The play-off first legs were played on 8 October 2010, while the second legs were played on 12 October 2010. Winners of play-off round and host nation Denmark will participate in the championship next year.\nMatches.\nThe draw took place on 10 September 2010 in Herning, Denmark. Fourteen teams were drawn into seven two-legged ties. The matches between Iceland and Scotland were moved back a day to avoid a fixture clash with full internationals.\nSecond leg.\n\"Switzerland won 5–2 on aggregate\"\n\"Iceland won 4–2 on aggregate\"\n\"England won 2–1 on aggregate\"\n\"Spain won 5–1 on aggregate\"\n\"Belarus won 3–2 on aggregate\"\n\"Czech Republic won 5–0 on aggregate\"\n\"3–3 on aggregate, Ukraine won on away goals rule.\"", "Engineering,_Manufacturing": 0.9959443808, "qwen": "Yes"}
{"id": "24244997", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=24244997", "title": "Whinfield coke works", "text": "Whinfield coke works was a large industrial complex located near Rowlands Gill in Tyne and Wear, North East England. The complex comprised a coking plant, alloy factory and power station. Waste heat from the plant provided heat for a power station. This was later converted to generate electricity by burning coke.\nAlloy factory.\nAn alloy factory was opened in 1909 and was operated by the Newcastle Alloy Company, producing ferro alloys such as ferrosilicon, ferromolybdenum, ferrotungsten and ferrochrome. Because ferrochrome was an important ingredient in the manufacture of armoured steel, and Whinfield was the only manufacturer of this alloy in England, the factory was extended during World War I.\nAt the end of World War I the demand for the alloy quickly vanished and the Newcastle Alloy Company went into liquidation in 1922 and the factory closed.\nPower station.\nThe station was built in 1896 to utilise waste heat from the coke works. The waste heat was used to make steam which powered generators and produced electricity. Initially the electricity powered the Victoria Garesfield Colliery and lit the coke works. In 1902 the station began providing electricity to light the villages of Victoria Garesfield, Highfield, Barlow and Rowlands Gill.\nThe station had further surplus electricity, which was used in an alloy factory adjacent to the coke works. A new alloy factory was built and the power station was also extended with the building of a new station in 1914. This station used Babcock & Wilcox boilers, which burned coke instead of just using waste heat from the works. Its generating capacity was larger than that of the Dunston A power station. As demand increased, electric supplies were supplemented with the laying of a cable from Dunston power station to Whinfield in 1917.\nFollowing the closure of the alloy factory after World War I, the power station's surplus electricity was sold to the Newcastle-upon-Tyne Electric Supply Company to supply Tyneside, exported using the cable from Dunston. The station closed in 1932 with the introduction of the national grid. It operated on a 50 hertz (Hz) frequency, and it would have proven uneconomical to convert Whinfield from its 40 Hz frequency, and so it closed down. The station's main structure was still standing in the late 1970s, but has since been demolished.\nPresent.\nWhinfield Industrial Estate has since been built on the site.", "Engineering,_Manufacturing": 0.9992606044, "qwen": "Yes"}
{"id": "372426", "revid": "154991", "url": "https://en.wikipedia.org/wiki?curid=372426", "title": "Production equipment control", "text": "Production equipment control involves production equipment that resides in the shop floor of a manufacturing company and its purpose is to produce goods of a wanted quality when provided with production resources of a required quality. In modern production lines the production equipment is fully automated using industrial control methods and involves limited unskilled labour participation. Modern production equipment consists of mechatronic modules that are integrated according to a control architecture. The most widely known architectures involve hierarchy, polyarchy, hetaerarchy and hybrid. The methods for achieving a technical effect are described by control algorithms, which may or may not utilize formal methods in their design.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "33238402", "revid": "1132472154", "url": "https://en.wikipedia.org/wiki?curid=33238402", "title": "Capacitor discharge sintering", "text": "Capacitor discharge sintering (CDS) is an electric current assisted sintering (ECAS) technique. The technique is based on storage of electromagnetic energy in a high voltage capacitor bank, and discharge into the sintering apparatus at low voltage (transformers on a pre-compacted powder compact which is kept under pressure. The sintering mould and Electrodes are similar to those employed in field assisted sintering techniques (FAST) such as spark plasma sintering and single electromagnetic pulse sintering technologies.\nThe method, analogous to resistive sintering, is a direct evolution of a welding technology named Capacitor Discharge Welding . CDS seems like an improvement of the less powerful capacitor discharge compaction patented by W.Knoess and M.Schlemmer (EP 0671232, US Patent 5529746).\nAdvantages of the technique are:\nDisambiguation.\nThe technique has been studied by Element Six under the name of electro-discharge sintering. This name has been adopted by many authors in the past to describe a range of different technologies which typically adopt very high voltages and completely different machines. For this reason the technique which employs low voltages and high currents adapted from capacitor discharge welding has been named capacitor discharge sintering. Other authors also refer to this technology as spark plasma compaction (in reference to the well known spark plasma sintering with whom it has in common only the use of electric currents).\nDevelopments.\nCapacitor discharge sintering is at an experimental/research stage of development in Germany at the Ruhr-Universität Bochum where a prototype machine is installed.", "Engineering,_Manufacturing": 0.999994874, "qwen": "Yes"}
{"id": "33249804", "revid": "39565592", "url": "https://en.wikipedia.org/wiki?curid=33249804", "title": "Birk Manufacturing", "text": "Birk Manufacturing is a privately owned manufacturing company based in East Lyme, Connecticut. Birk engineers and manufactures custom flexible thermal solutions and temperature sensor assemblies for multiple industries including the medical, defense, aerospace, semi-conductor, food service and commercial industries. Birk's main product offerings are Polyimide (Kapton) and Silicone Rubber flexible heating elements.\nBirk specializes in engineering and manufacturing components for the most challenging applications, and performs all design and manufacturing at their headquarters in East Lyme, CT.\nHistory.\nBirk Manufacturing was formed in 1989 by Norman Birk, the current owner of Birk Manufacturing. Norman served as president of Birk Manufacturing for the company's first 21 years, guiding Birk from a \"start-up\" company to the industry leader it is today. Birk continues to grow and develop new products and innovations in thermal management.\nCertifications.\nBirk currently holds UL, CSA, AS9100, ISO 9001, ISO 13485 and ITAR certifications.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "55293246", "revid": "42528041", "url": "https://en.wikipedia.org/wiki?curid=55293246", "title": "Theory of Constraints in streamline manufacturing", "text": "Theory of constraints (TOC) is an engineering management technique used to evaluate a manageable procedure, identifying the largest constraint (bottleneck) and strategizing to reduce task time and maximise profit. It assists in determining what to change, when to change it, and how to cause the change. The theory was established by Dr. Eliyahu Goldratt through his 1984 bestselling novel The Goal. Since this time, TOC has continued to develop and evolve and is a primary management tool in the engineering industry. When Applying TOC, powerful tools are used to determine the constraint and reduce its effect on the procedure, including:\nAlthough still limited by varying factors, time factors and human identification, TOC is the ideal engineering solution to increasing profit and reducing idle time in a production through its elimination of 'the weak link.'\nHistory.\nTheory of Constraints is a method to determine a procedure in a sequence of procedures which has the greatest negative effect on the production line. The theory was first derived by Dr Eliyahu Goldratt through his 1984 bestselling novel, 'The Goal.' Dr Goldratt was a well-regarded educator in the construction industry, being sought-after by many large companies. In the mid 1990s, Goldratt in 2000, established Goldratt's Marketing Group to further enhance the TOC knowledge to those interested. Goldratt's Marketing Group was established to further enhance the knowledge of businesses in product production, suppliers and distributors, project managers and retail workers, further develop the quality of decision-making, improving communication and stimulating new solutions.\nThe theory operates with the assumption that every process has at least one influencing constraint, of which must be improved for the process to become more economic. Time spent trying to maximise processes which are not considered the bottleneck will not provide any benefits to the system. Attempting to reduce the influencing factor the bottleneck has on the entire system, will further the 'goal.' The procedure of reducing the influencing factor the bottleneck has on the system, continues as one bottleneck is minimised the attention turns to the new largest hindering procedure.\nBottleneck.\nIn streamline manufacturing, the bottleneck is the station of a production line where greatest limiting factor lies. It is generally the station with the greatest amount of work in process at the work station. Bottlenecks often results in slow production times, surplus of raw material and low employee morale.\nNearly every manufacturing system initially has a bottleneck. It is critical to be able to determine the procedure in the production line which is the limiting factor. Generally the station which has accumulated the largest amount of WIP can be considered the Bottleneck, however other engineering management techniques can be applied to determine the bottle neck.\nApplication.\nThere are several practiced techniques applied to streamline manufacturing to reduce and or eliminate the constraining factor in the system. The methods applied to the systems all are designed to isolate the constraint, break it down into its components and find a suitable solution to reducing the negative impact the station has on the entire system. The thinking processes as well as the identification of the bottleneck is conducted in different manners. The four most common practiced techniques include; Five Focusing Steps, Thinking Process, Throughput Accounting and the Drum-Buffer-Effect.\nFive Focusing Steps.\nThe five focusing steps of TOC is an ideal approach to identifying the bottleneck and the correct procedure to reduce the impact keeping in mind the 'goal.' The five focusing steps are:\nIdentify the Constraint.\nThe first step is to determine which process in the system is increasing the procedures overall throughput. Indicators of the bottleneck in the system will have accumulated a large amount of work in progress (WIP) and will have a higher average cycle time.\nExploit the Constraint.\nExploiting the constraint is the procedure of quickly improving the current bottleneck with minimal disruption to the production line. Common rapid relief techniques include:\nImprovements in these fields will have a quick solution to improvement of the constraint which will result in improved throughput\nSubordinate to the Constraint.\nThis step focuses on techniques to mitigate impact from upstream or downstream processes which may further delay the operations of the bottleneck. Techniques include:\nElevate the Constraint.\nIn this step, actions are taken to break the constraints by the implementation of larger changes to improve the bottleneck. These changes usually include a large investment of time and or money. Techniques used include:\nRepeat the Process.\nOnce the initial steps of the Five Focusing Steps have been executed, the bottleneck of focus should no longer be the hindering process of the system. The implementation of the Five Focusing Steps is not used for one off improvement but for continuous improvements to the process. If the bottleneck has been broken, the next step is to repeat the focusing steps for the new bottleneck. If the bottleneck has not been broken, a new approach needs to be taken, including verifying that the investigated constraint has correctly been identified as the bottleneck.\nThinking Process.\nThe thinking process in TOC, are tools used to determine, and fixing a problem in a system. In streamline processing it is a fundamental approach to always be striving to improve processes, eliminate bottlenecks and reduce manufacturing time. A common approach is to answer the following questions:\nAsking these questions when faced with a problem in a production line, will offer a range of solutions simultaneously to improve the current situation. The thinking process allows a smooth transition through the layers of the process to be able to adapt a more suitable method to improve the manufacturing system.\nThroughput Accounting.\nThroughput accounting (TA) is a simple management accounting technique providing managers with information support to make profitable decisions for their system. It is an alternative method to traditional cost accounting, in which limiting factors in a system are identified and simple solutions are adapted to move towards reaching the businesses goal. The actions of throughput accounting maximize the net profit from a system in the shortest amount of time, with limited resources and limited expenditures.\nThroughput accounting uses through methods in dealing with income and expenses in a system\nThroughput (T) is the rate at which a system can produce a unit. For profit orientated systems, throughput is considered net sales (S) minus totally variable cost (TVC).\nInvestment (I) is the monetary value of the system. The value of inventory, buildings, machines and other assets are considered investments.\nOperating expenses (OE) is the cost of the supply chain operating to produce the unit. For a system manufacturing a physical item, the operating expense is the investment cost minus the cost of raw materials but including the cost of maintenance, rent and taxes.\nConstraints and Limitations.\nA key process in TOC is the identification of the limiting factor in a production system to ultimately improve the production of units. A major limitation in the theory is that of identifying the station which is in fact the limiting procedure.\nIdentification.\nIt is not uncommon that when applying TOC the wrong work station is being examined as the limiting station when, however this station may only be the bottleneck due to another constraining factor not being focused on. This limitation theory, may encourage the waste of resources and times on a station which may in fact not require optimizing.\nVariation.\nAnother limitation of the theory is the lack of consideration towards varying factors. Factors such as demand for a product are not directly examined when TOC is applied. If the market demand for a product is varying, the use of resources to improve the situation may be better used expanding production capacity.\nTime.\nTime is an influential constraint when applying TOC. The theory does not consider the current time frame for the production system and the duration of the demand for the product. The theory limits itself to short-term effects on the system rather than forecasting for the future. Overcoming this constraint means examining the long-term effects of work done to improve the constraint. If findings in a short-term analysis seem to repeat they can be considered as long-term effects, therefore implementing changes may be appropriate.", "Engineering,_Manufacturing": 0.9989733696, "qwen": "Yes"}
{"id": "51887490", "revid": "1144740941", "url": "https://en.wikipedia.org/wiki?curid=51887490", "title": "Wearwell", "text": "The Wearwell Cycle Company was a bicycle manufacturing company founded in 1889 in Wolverhampton by the five sons of Henry Clarke, founder of the late Cogent Cycle Company. Wearwell were also motorcycle manufacturers under the Wearwell Stevens, Wolf and Wulfruna brands.\nIn 1928 Jack Waine and his brother George Waine took over the Wearwell Cycle Company Ltd. from the liquidators of the Wulfruna Engineering Co Ltd. The new company was registered as the Wearwell Cycle Co. (1928) Ltd and Jack's son Vincent and George's son Theo were brought on as Directors. They also purchased the plant, tools and stock-in-trade of the cycle manufacturing side of the Vulcan Manufacturing Co. (Wolverhampton) Ltd.\nBy 1929 a full range of cycles was offered including tradesmen's cycles, juvenile cycles, scooters, and the distinctive 'Duplex'. In 1931 the company showed the new 'Schneider' sports machine at Olympia, and a cheaper version called the 'Wanderer'.\nThe company produced motorcycles until the outbreak of World War II, from which point they manufactured only bicycles. The factory was partly destroyed by fire during an air raid but some production was soon restored. After World War II production of cycles continued and motorcycle production resumed.\nBy the middle of the 20th Century, 75% of the company's production was exported to over 30 different countries. The company began sponsoring a professional cycle team through the 1950s, winning the Tour of Britain cycle race in 1953, which was amongst the team's best domestic racing highlights. Riders in the victorious Wearwell Cycle Company Team were Les Scales, John Pottier, Ian Greenfield, Trevor Fenwick, Ken Mitchell and John Welch.\nThe Vulcan Manufacturing group went into voluntary liquidation in 1969, and its assets were sold off. In 1972 Wearwell Cycle Company was sold off and its production was moved out of Wolverhampton to Aleveley, near Bridgnorth, but was subsequently sold onto Elswick-Hopper Cycle Company where production was moved to Brigg in Lincolnshire. It survived a few more years until the company was finally closed in 1975. A great-great-grandson has revived the Wearwell name in 2017 as a cycling clothes company.", "Engineering,_Manufacturing": 0.9983038306, "qwen": "Yes"}
{"id": "51907205", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=51907205", "title": "Process management (project management)", "text": "In civil engineering and project management, process management is the management of \"systematic series of activities directed towards causing an end result such that one or more inputs will be acted upon to create one or more outputs\".\nProcess management offers project organizations a means of applying the same quality improvement and defect reduction techniques used in business and manufacturing processes by taking a process view of project activity; modeling discrete activities and high-level processes.\nOverview.\nThe term \"process management\" usually refers to the management of engineering processes and project management processes where a \"process\" is a collection of related, structured tasks that produce a specific service or product to address a certain goal for a particular actor or set of actors.\nProcesses can be executed with procedures. They can be described as a sequence of steps that can execute a process and their value lies in that they are an accepted method of accomplishing a consistent performance or results.\nProcess management provides engineering and project managers with a means of systemically thinking of project organizations, semantics concepts and logical frameworks that allow project activities to be planned, executed, analyzed and facilitate learning.\nIn order for process management as defined to deliver consistent performance, it requires definition, elimination of non-value-added activities, continuous improvement, project stakeholder focus and team based approach. Mitchell (2016) notes that managing processes across divisional and organizational boundaries requires a more flexible management strategy as well as close cooperation among managers in diverse functional and operational units to ensure that the process flow is not interrupted by conflicts over lines of authority.\nHistory.\nProcess management originated as part of the manufacturing-based application of statistical quality control movement in the late 1920s and early 1930s. What is relatively new, however, is the transition of process management methods from a manufacturing environment to a total company orientation and project management.\nProcess management in the context of project management or engineering represents a change from the traditional concept of organizational authority using hierarchies and organizational structure to one requiring flexibility to ensure efficient process workflows. Mitchell (2016) notes that managing processes across divisional and organizational boundaries requires a more flexible management strategy as well as close cooperation among managers in diverse functional and operational units to ensure that the process flow is not interrupted by conflicts over lines of authority.\nCooper, et al. note that manufacturing has been \"a constant reference point and a source of innovation in construction\". There is a new phenomenon occurring within the construction sector that is based upon the development and use of fundamental core management processes to improve the efficiency of the industry.\nTopics.\nThe notion of process.\nIn the field of process management the notion of process, according to Mitchell (2016), can be characterized by: \nThese concepts provides management with the following:\nProcess management in this context requires engineering knowledge, management activities and skill sets whereas business processes or manufacturing processes require operations management activities, and skill sets.\nTools and models.\nProcess models are 'an effective way to show how a process works'. Project management process modeling tools provide managers and engineering professionals with the ability to model their processes, implement and execute those models, and refine the models based on actual performance. The result is that business process modeling tools can provide transparency into project management processes, as well as the centralization of project organization process models and execution metrics.\nA number of modelling/systems analysis techniques exist such as data flow diagrams (DFD), HIPO model (hierarchy + input-process-output), data modeling and IDEF0 (integration definition language 0 for function modelling) process modelling technique.\nThreaded processes.\nA process activity that is concurrent or simultaneously executing can be termed a thread.\nISO 9000.\nISO 9000 promotes the process approach to managing an organization.\n ...promotes the adoption of a process approach when developing, implementing and\nimproving the effectiveness of a quality management system, to enhance customer satisfaction by meeting customer requirements.", "Engineering,_Manufacturing": 1.0000047684, "qwen": "Yes"}
{"id": "20719521", "revid": "28032115", "url": "https://en.wikipedia.org/wiki?curid=20719521", "title": "Die swell", "text": "Die swell, also known as extrudate swell or Barus effect, is a common phenomenon in polymer processing. Die swell occurs in instances of polymer extrusion, in which a stream of polymeric material is forced through a die, a specialized tool in manufacturing to shape or cut polymeric materials. Die swell is an instance where a polymer stream is compressed by entrance into a die, and is followed by a partial recovery or \"swell\" back to the former shape and volume of the polymer after exiting the die, hence the term die swell.\nDie swell is a phenomenon directly related to entropy and the relaxation of the polymer within the flow stream. Initially, a flow stream has a constant rate before entering the die, and the polymers within the stream occupy a roughly spherical conformation, maximizing entropy. Extrusion through the die causes an increase in flow rate through the polymer flow stream. As the polymer spends time inside the die and is subject to the much increased flow rate, the polymers lose the spherical shape, becoming longer due to the increased flow rate. Physical entanglements may relax, if the time scale of the polymer within the die is long enough. When the polymer stream leaves the die, the remaining physical entanglements cause the polymers in the die stream to regain a portion of its former shape and spherical volume, in order to return to the roughly spherical conformation that maximizes entropy.\nThe disentanglement of polymer chains is a kinetic process, and so the longer the die is, the more time is given for the physical entanglements within the polymer stream to disentangle. With a longer die and a slower polymer flow stream, less pronounced die swell will be observed. This is due to the longer die providing a longer time period for polymer, when subject to the increase flow rate, to disentangle. This characteristic relaxation time determines the length of time the polymer must spend inside the die to minimize die swell.", "Engineering,_Manufacturing": 0.9996154904, "qwen": "Yes"}
{"id": "26979719", "revid": "1163513821", "url": "https://en.wikipedia.org/wiki?curid=26979719", "title": "Laser drilling", "text": "Laser drilling is the process of creating thru-holes, referred to as “popped” holes or “percussion drilled” holes, by repeatedly pulsing focused laser energy on a material. The diameter of these holes can be as small as 0.002” (~50 μm). If larger holes are required, the laser is moved around the circumference of the “popped” hole until the desired diameter is created.\nApplications.\nLaser drilling is one of the few techniques for producing high-aspect-ratio holes—holes with a depth-to-diameter ratio much greater than 10:1.\nLaser-drilled high-aspect-ratio holes are used in many applications,\nincluding the oil gallery of some engine blocks, aerospace turbine-engine cooling holes,\nlaser fusion components, and printed circuit board micro-vias.\nManufacturers of turbine engines for aircraft propulsion and for power generation have benefited from the productivity of lasers for drilling small (0.3–1 mm diameter typical) cylindrical holes at 15–90° to the surface in cast, sheet metal and machined components. Their ability to drill holes at shallow angles to the surface at rates of between 0.3 and 3 holes per second has enabled new designs incorporating film-cooling holes for improved fuel efficiency, reduced noise, and lower NOx and CO emissions.\nIncremental improvements in laser process and control technologies have led to substantial increases in the number of cooling holes used in turbine engines. Fundamental to these improvements and increased use of laser drilled holes is an understanding of the relationship between process parameters and hole quality and drilling speed.\nTheory.\nFollowing is a summary of technical insights about the laser drilling process and the relationship between process parameters and hole quality and drilling speed.\nPhysical phenomena.\nLaser drilling of cylindrical holes generally occurs through melting and vaporization (also referred to as \"ablation\") of the workpiece material through absorption of energy from a focused laser beam.\nThe energy required to remove material by melting is about 25% of that needed to vaporize the same volume, so a process that removes material by melting is often favored.\nWhether melting or vaporization is more dominant in a laser drilling process depends on many factors, with laser pulse duration and energy playing an important role. Generally speaking, ablation dominates when a Q-switched Nd:YAG laser is used. On the other hand, melt expulsion, the means by which a hole is created through melting the material, dominates when a flashtube pumped Nd:YAG laser is used. A Q-switched Nd:YAG laser normally has pulse duration in the order of nanoseconds, peak power on the order of ten to hundreds of MW/cm2, and a material removal rate of a few micrometers per pulse. A flash lamp pumped Nd:YAG laser normally has a pulse duration on the order of hundreds of microseconds to a millisecond, peak power in the order of sub MW/cm2, and material removal rate of ten to hundreds of micrometers per pulse. For machining processes by each laser, ablation and melt expulsion typically coexist.\nMelt expulsion arises as a result of the rapid build-up of gas pressure (recoil force) within a cavity created by evaporation. For melt expulsion to occur, a molten layer must form and the pressure gradients acting on the surface due to vaporization must be sufficiently large to overcome surface tension forces and expel the molten material from the hole.\nThe \"best of both worlds\" is a single system capable of both \"fine\" and \"coarse\" melt expulsion. \"Fine\" melt expulsion produces features with excellent wall definition and small heat-affected zone while \"coarse\" melt expulsion, such as used in percussion drilling, removes material quickly.\nThe recoil force is a strong function of the peak temperature. The value of Tcr for which the recoil and surface tension forces are equal is the critical temperature for liquid expulsion. For instance, liquid expulsion from titanium can take place when the temperature at the center of the hole exceeds 3780 K.\nIn early work (Körner, et al., 1996), the proportion of material removed by melt expulsion was found to increase as intensity increased. More recent work (Voisey, et al., 2000) shows that the fraction of the material removed by melt expulsion, referred to as melt ejection fraction (MEF), drops when laser energy further increases. The initial increase in melt expulsion on raising the beam power has been tentatively attributed to an increase in the pressure and pressure gradient generated within the hole by vaporization.\nA better finish can be achieved if the melt is ejected in fine droplets. Generally speaking, droplet size decreases with increasing pulse intensity. This is due to the increased vaporization rate and thus a thinner molten layer. For the longer pulse duration, the greater total energy input helps form a thicker molten layer and results in the expulsion of correspondingly larger droplets.\nPrevious models.\nChan and Mazumder (1987) developed a 1-D steady state model to incorporate liquid expulsion consideration but the 1-D assumption is not suited for high aspect ratio hole drilling and the drilling process is transient. Kar and Mazumder (1990) extended the model to 2-D, but melt expulsion was not explicitly considered. A more rigorous treatment of melt expulsion has been presented by Ganesh, et al. (1997), which is a 2-D transient generalized model to incorporate solid, fluid, temperature, and pressure during laser drilling, but it is computationally demanding. Yao, et al. (2001) developed a 2-D transient model, in which a Knudsen layer is considered at the melt-vapor front, and the model is suited for shorter pulse and high peak power laser ablation.\nLaser energy absorption and melt-vapor front.\nAt the melt-vapor front, the Stefan boundary condition is normally applied to describe the laser energy absorption (Kar and Mazumda, 1990; Yao, et al., 2001).\nwhere formula_2 is the absorbed laser intensity, \"β\" is the laser absorption coefficient depending on laser wavelength and target material, and \"I(t)\" describes temporal input laser intensity including pulse width, repetition rate, and pulse temporal shape. \"k\" is the heat conductivity, \"T\" is the temperature, \"z\" and \"r\" are distances along axial and radial directions, \"p\" is density, \"v\" the velocity, \"Lv\" the latent heat of vaporization. The subscripts \"l\", \"v\" and \"i\" denote liquid phase, vapor phase and vapor-liquid interface, respectively.\nIf the laser intensity is high and pulse duration is short, the so-called Knudsen layer is assumed to exist at the melt-vapor front where the state variables undergo discontinuous changes across the layer. By considering the discontinuity across the Knudsen layer, Yao, et al. (2001) simulated the surface recess velocity Vv distribution, along the radial direction at different times, which indicates the material ablation rate is changing significantly across the Knudsen layer.\nMelt expulsion.\nAfter obtaining the vapor pressure \"pv\", the melt layer flow and melt expulsion can be modeled using hydrodynamic equations (Ganesh et al.,1997). Melt expulsion occurs when the vapor pressure is applied on the liquid free surface which in turn pushes the melt away in the radial direction. In order to achieve fine melt expulsion, the melt flow pattern needs to be predicted very precisely, especially the melt flow velocity at the hole's edge. Thus, a 2-D axisymmetric transient model is used and accordingly the momentum and continuity equations used.\nGanesh's model for melt ejection is comprehensive and can be used for different stages of the hole drilling process. However, the calculation is very time consuming and Solana, et al. (2001), presented a simplified time dependent model that assumes that the melt expulsion velocity is only along the hole wall, and can give results with a minimum computational effort.\nThe liquid will move upwards with velocity u as a consequence of the pressure gradient along the vertical walls, which is given in turn by the difference between the ablation pressure and the surface tension divided by the penetration depth \"x\".\nAssuming that the drilling front is moving at a constant velocity, the following linear equation of liquid motion on the vertical wall is a good approximation to model the melt expulsion after the initial stage of drilling.\nwhere \"p\" is the melt density, \"μ\" is the viscosity of the liquid, \"P(t)=(ΔP(t)/x(t))\" is the pressure gradient along the liquid layer, \"ΔP(t)\" is the difference between the vapor pressure \"Pv\" and the surface tension formula_4.\nPulse shape effect.\nRoos (1980) showed that a 200 µs train consisting of 0.5 µs pulses produced superior results for drilling metals than a 200 µs flat shaped pulse. Anisimov, et al. (1984) discovered that process efficiency improved by accelerating the melt during the pulse.\nGrad and Mozina (1998) further demonstrated the effect of pulse shapes. A 12 ns spike was added at the beginning, middle, and the end of a 5 ms pulse. When the 12 ns spike was added to the beginning of the long laser pulse, where no melt had been produced, no significant effect on removal was observed. On the other hand, when the spike was added at the middle and the end of the long pulse, the improvement of the drilling efficiency was 80 and 90%, respectively. The effect of inter-pulse shaping has also been investigated. Low and Li (2001) showed that a pulse train of linearly increasing magnitude had a significant effect on expulsion processes.\nForsman, et al. (2007) demonstrated that a double pulse stream produced increased drilling and cutting rates with significantly cleaner holes.\nConclusion.\nManufacturers are applying results of process modeling and experimental methods to better understand and control the laser drilling process. The result is higher quality and more productive processes that in turn lead to better end products such as more fuel efficient and cleaner aircraft and power generating turbine engines.", "Engineering,_Manufacturing": 1.000007987, "qwen": "Yes"}
{"id": "26981085", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=26981085", "title": "Machine element", "text": "Machine element or hardware refers to an elementary component of a machine. These elements consist of three basic types:\nWhile generally not considered to be a machine element, the shape, texture and color of covers are an important part of a machine that provide a styling and operational interface between the mechanical components of a machine and its users.\n\"Machine elements\" are basic mechanical parts and features used as the building blocks of most machines. Most are standardized to common sizes, but customs are also common for specialized applications. \nMachine elements may be features of a part (such as screw threads or integral plain bearings) or they may be discrete parts in and of themselves such as wheels, axles, pulleys, rolling-element bearings, or gears. All of the simple machines may be described as machine elements, and many machine elements incorporate concepts of one or more simple machines. For example, a leadscrew incorporates a screw thread, which is an inclined plane wrapped around a cylinder. \nMany mechanical design, invention, and engineering tasks involve a knowledge of various machine elements and an intelligent and creative combining of these elements into a component or assembly that fills a need (serves an application).", "Engineering,_Manufacturing": 1.0000063181, "qwen": "Yes"}
{"id": "33746269", "revid": "73985", "url": "https://en.wikipedia.org/wiki?curid=33746269", "title": "Materialise NV", "text": "Materialise NV, headquartered in Leuven, Belgium, is a company in the 3D printing / additive manufacturing sector.\nHistory.\n1990s.\nMaterialise was founded in June 1990 by Wilfried Vancraen and his wife Hilde Ingelaere as a Rapid Prototyping service bureau. It was the first company of its kind in the Benelux region of Europe, through the acquisition of a single Stereolithography machine (the SLA 1).\nIn 1992, Materialise began mapping human anatomy digitally in three dimensions, using sliced CT image data, which lead to the development of its medical image processing software: Mimics. Concurrently, the team was also developing its industrial software solution, Magics. Both of these software solutions were later commercialized to promote growth.\n1995 was the year that Materialise became the first company to produce 3D printed parts in more than one colour, specifically at this time for anatomical models produced using the stereolithography process to delineate the complexities of the anatomy (such as nerves, blood vessels and tumours) and allow surgeons to more precisely plan for operations.\nThe company developed and produced the first customised 3D printed surgical guide for a dental operation in 1996. These personalised guides were utilised during surgery to show surgeons bone cutting and drilling locations to apply implants. This knowledge was used to develop Materialise SimPlant software, allowing the surgeon to virtually plan the surgery and minimize invasive exploratory surgery.\nThe company launched one of the first 3D printing online ordering systems in 1997, Materialise NextDay, which later became Materialise OnSite. This service allowed 3D printing service customers to send digital 3D data, which could be printed and shipped the next day.\nDemand for prototypes grew, leading Materialise to develop its Mammoth Stereolithography systems, which are capable of printing single-piece models with dimensions of more than 2 meters in the Y axis.\n2000s.\nIn the year 2000, hearing aid specialist Phonak approached Materialise to develop the Rapid Shell Modeling (RSM) software. This allowed the design process for customized, patient-specific hearing aid shells to become automated. The resulting designs could then be 3D printed to produce the customised hearing aids. This was the first high volume, end-use application of 3D printing, and today, 99% of the world's hearing aids are now produced using 3D printing.\nMaterialise acquired US company Columbia Scientific Inc, (CSI) in 2001, the creators of Sim/Plant and ImageMaster, which became the US headquarters for Materialise's dental division in that region.\nIn 2003 Materialise launched one of the first 3D printed consumer brands — .MGX by Materialise — for 3D printing end-use products as well as prototypes. In parallel, the company also acquired Fused Deposition Modelling (FDM) systems for industrial applications.\nThe following year, in 2004, Materialise introduced its 3-matic software, allowing 3D printer users to edit files directly in the STL format. Previously, if design changes were required in the digital model, designers had to make them in the CAD suite of choice before re-converting the entire file to STL again.\nIn 2006 Materialise launched RapidFit, developed as a 3D printed solution for shipping large parts with customized jigs and fixtures to prevent deformation or breakage while in transit.\nIn 2006 Materialise developed the first Titanium 3D printed skull implants, following the acquisition of OBL, which specialized in the creation of custom cranio-maxillfacial (CMF) implants, producing customized implants with intricate porous structures, that behave like natural bone and mimic its mechanical and thermal properties.\nIn 2008 Materialise introduced the e-Stage software which was the first software to automatically generate support structures for different geometries in Stereolitography. In the same year, the company launched i.materialise for the consumer market, making it possible for anyone to print their ideas using professional-quality equipment. Materialise also developed its first Build Processor to support running different 3D printing processes more efficiently within a single location.\n2010s.\nIn 2012, Materialise introduced Streamics to provide traceable quality control to industrial 3D printer users producing end-use parts within regulated industries.\nMaterialise went public on June 25, 2014 to enable expansion of its services and software development. The same year the company acquired OrthoView, a market leader in orthopaedic digital pre-operative planning software and officially established a new office in China in December with a focus on 3D printing Software and R&D, namely Materialise Shanghai Co. Ltd.\nIn 2016, the company opened a new and dedicated metal production facility in Bremen, Germany. Materialise HQ, Leuven, also acquired and started testing the multi jet fusion (MJF) process from HP. Production of parts with MJF started in the following year, 2017.\nWith the expansion of the AM Metal market, Materialise acquired ACTech in Germany to extend the company's metal capabilities, with a specific emphasis on low-volume production of highly complex metal parts. The acquisition also enabled Materialise to develop and improve its software suite for metal 3D printing.", "Engineering,_Manufacturing": 0.9999582767, "qwen": "Yes"}
{"id": "11961539", "revid": "18285885", "url": "https://en.wikipedia.org/wiki?curid=11961539", "title": "MADEI", "text": "MADEI has been assembling Japanese commercial vehicles in Myanmar for decades.\nRecently, it was commissioned by the government to manufacture jeeps.\nManufactured at six industrial zones under government supervision, the models are Super Mandala Jeep from Mandalay Industrial Zone, Myay Latt Jeep from Myingyan Industrial Zone, Htila Jeep from Meikhtila Industrial zone, Chindwin Star Jeep from Monywa Industrial Zone, Shan Star Jeep from Ayethaya Industrial Zone in Taunggyi and PKU Jeep from Pakokku Industrial Zone. Body is made locally, while the mechanical parts are imported from Japan.\nProduction rate was approximately 100 annually.", "Engineering,_Manufacturing": 0.9997984767, "qwen": "Yes"}
{"id": "11982591", "revid": "9039270", "url": "https://en.wikipedia.org/wiki?curid=11982591", "title": "Smart cut", "text": "Smart cut is a technological process that enables the transfer of very fine layers of crystalline silicon material onto a mechanical support. It was invented by Michel Bruel of , and was protected by US patent 5374564. The application of this technological procedure is mainly in the production of silicon-on-insulator (SOI) wafer substrates.\nThe role of SOI is to electronically insulate a fine layer of monocrystalline silicon from the rest of the silicon wafer; an ultra-thin silicon film is transferred to a mechanical support, thereby introducing an intermediate, insulating layer. Semiconductor manufacturers can then fabricate integrated circuits on the top layer of the SOI wafers using the same processes they would use on plain silicon wafers. \nThe sequence of illustrations pictorially describes the process involved in fabricating SOI wafers using the smart cut technology.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "14679376", "revid": "41722878", "url": "https://en.wikipedia.org/wiki?curid=14679376", "title": "Highly accelerated life test", "text": "A highly accelerated life test (HALT) is a stress testing methodology for enhancing product reliability in which prototypes are stressed to a much higher degree than expected from actual use in order to identify weaknesses in the design or manufacture of the product. Manufacturing and research and development organizations in the electronics, computer, medical, and military industries use HALT to improve product reliability.\nHALT can be effectively used multiple times over a product's life time. During product development, it can find design weakness earlier in the product lifecycle when changes are much less costly to make. By finding weaknesses and making changes early, HALT can lower product development costs and compress time to market. When HALT is used at the time a product is being introduced into the market, it can expose problems caused by new manufacturing processes. When used after a product has been introduced into the market, HALT can be used to audit product reliability caused by changes in components, manufacturing processes, suppliers, etc.\nOverview.\nHighly accelerated life testing (HALT) techniques are important in uncovering many of the weak links of a new product. These discovery tests rapidly find weaknesses using accelerated stress conditions. The goal of HALT is to proactively find weaknesses and fix them, thereby increasing product reliability. Because of its accelerated nature, HALT is typically faster and less expensive than traditional testing techniques.\nHALT is a test technique called test-to-fail, where a product is tested until failure. HALT does not help to determine or demonstrate the reliability value or failure probability in field. Many accelerated life tests are test-to-pass, meaning they are used to demonstrate the product life or reliability.\nIt is highly recommended to perform HALT in the initial phases of product development to uncover weak links in a product, so that there is better chance and more time to modify and improve the product.\nHALT uses several stress factors (decided by a Reliability Test Engineer) and/or the combination of various factors. Commonly used stress factors are temperature, vibration, and humidity for electronics and mechanical products. Other factors can include voltage, current, power cycling and combinations of them.\nTypical HALT procedures.\nEnvironmental stresses are applied in a HALT procedure, eventually reaching a level significantly beyond that expected during use. The stresses used in HALT are typically hot and cold temperatures, temperature cycles, random vibration, power margining, and power cycling. The product under test is in operation during HALT and is continuously monitored for failures. As stress-induced failures occur, the cause should be determined, and if possible, the problem should be repaired so that the test can continue to find other weaknesses.\nOutput of the HALT gives you:\nTest chambers.\nA specialized environmental chamber is required for HALT. A suitable chamber also has to be capable of applying pseudo-random vibration with a suitable profile in relation to frequency. The HALT chamber should be capable of applying random vibration energy from 2 to 10,000 Hz in 6 degrees of freedom and temperatures from -100 to +200°C. Sometimes HALT chambers are called repetitive shock chambers because pneumatic air hammers are used to produce vibration. The chamber should also be capable of rapid changes in temperature, 50°C per minute should be considered a minimum rate of change. Usually high power resistive heating elements are used for heating and liquid nitrogen (LN2) is used for cooling.\nFixtures.\nTest fixtures must transmit vibration to the item under test. They must also be open in design or use air circulation to produce rapid temperature change to internal components. Test fixtures can use simple channels to attach the product to the chamber table or more complicated fixtures sometimes are fabricated.\nMonitoring and failure analysis.\nThe equipment under test must be monitored so that if the equipment fails under test, the failure is detected. Monitoring is typically performed with thermocouple sensors, vibration accelerometers, multimeters and data loggers. Common causes of failures during HALT are poor product design, workmanship, and poor manufacturing. Failures to individual components such as resistors, capacitors, diodes, printed circuit boards occur because of these issues. Failure types found during HALT testing are associated with the infant mortality region of the bathtub curve.\nMilitary application.\nHALT is conducted before qualification testing. By catching failures early, flaws are found earlier in the acceptance process, eliminating repetitive later-stage reviews.", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "18516415", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=18516415", "title": "Spicule (glass manufacture)", "text": "Spicules are tiny glass flakes which are formed during the manufacture of glass vials. A glass tube is extruded at a constant rate and a jet of water applied to the hot glass is used to cut the blank tube to length. The bottom and lip of the vial are formed by swagging or upset forming while the glass is still hot.\nSpicules are formed in a cloud when the glass explodes from the contact of the cold jet. These are held to the glass blank during forming, and if the vial is not reheated or cleaned after manufacture, these spicules can drift off into the mixture subsequently placed in the vial. This is a serious problem in the manufacture of soft contact lenses or pharmaceutical products.", "Engineering,_Manufacturing": 0.9999263287, "qwen": "Yes"}
{"id": "33352238", "revid": "36510957", "url": "https://en.wikipedia.org/wiki?curid=33352238", "title": "Plate rolling machine", "text": "A plate rolling machine is a machine that will roll different kinds of sheet metal into a round or conical shape.\nIt can be also called a “roll bending machine”, “plate bending machine” or “rolling machine”.\nThere are different kinds of technology to roll the metal plate: \nThe flat metal plate is placed in the machine on either side and \"pre-bent\" on the same side. \nThe side rolls do the work of bending. The pinching roll holds the plate.\nThe three-roll variable pitch works by having all three rolls able to move and tilt. The top roll moves in the vertical plane and the side rolls move on the horizontal plane.\nWhen rolling, the top roll presses the metal plate between the two side rolls. The advantage of having the variable three roll is the ability to roll many thicknesses and diameters of cylinders.\nFor example;\nThe side-rolls are what produce the mechanical advantage. With the side rolls all the way open, one has the maximum mechanical advantage. With the side rolls all the way in, you have the least mechanical advantage.\nSo, a machine has the capability of rolling 2-inch-thick material with the maximum mechanical advantage, but a job is only 1/2 inch thick. Reduce the mechanical advantage and one has a machine that can roll from 1/2 to 2 inches thick.\nPlate rollers can be powered and controlled in multiple ways. Older plate mills are driven by electric motors and newer ones are directed by programs that are loaded into the CNC controller. When thinking about plate roll acquisition, industrial machinery companies like Provetco Technology will ask about the working length of the roller, the maximum thickness of the material, top roll diameter size as well as the minimum thickness of the material. Furthermore, the material yield is another critical component to disclose to machinery companies when looking for a plate roller.\nReferences.\nProvetco Technology: www.provetco.com", "Engineering,_Manufacturing": 1.0000071526, "qwen": "Yes"}
{"id": "33383655", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=33383655", "title": "Chemical Engineering and Biotechnology Abstracts", "text": "Chemical Engineering and Biotechnology Abstracts (CEABA-VTB) is an abstracting and indexing service that is published by DECHEMA, BASF, and Bayer Technology Services, all based in Germany. This is a bibliographic database that covers multiple disciplines.\nSubject coverage.\nSubject coverage includes engineering, management, manufacturing plants, equipment, production, and processing pertaining to various disciplines. The fields of interest are bio-process engineering, chemical engineering, process engineering, environmental protection (including safety), fermentation, enzymology, bio-transformation, information technology, technology and testing of materials (including corrosion), mathematical methods (including modeling), measurement (including control of processes), utilities (including services). Also covered are production processes and process development. CAS registry numbers are also part of this database.", "Engineering,_Manufacturing": 1.0000009537, "qwen": "Yes"}
{"id": "33397451", "revid": "41840956", "url": "https://en.wikipedia.org/wiki?curid=33397451", "title": "SolarPark Korea", "text": "SolarPark Korea Co., Ltd. is a South Korean crystalline silicon module manufacturer. Founded in 2008 as a German-Korean joint venture, the company combines German and Korean machinery and engineering in its automated module fabrication lines. In June 2011, SolarPark Korea became a 100% subsidiary of the SolarPark Co., Ltd.\nHistory.\nApril 1981\nThe automated machinery company INMAC is established in Sogong-dong, Joong-gu, Seoul, Korea\nJuly 1990\nA new factory is established in Songne-dong, Soda-gu, Bucheon-si, Gyeonggi-do, Korea\nThe headquarters is relocated to the same location\nMarch 1997\nINMAC is selected as a prospective medium & small enterprise of Gyeonggi-do\nApril 1999\nINMAC is selected as a prospective medium & small exporting enterprise\nApril 2007\nEstablishment of SolarPark Co., Ltd.\nNovember 2007\nSolarPark is awarded the 3 Million Dollar Export Tower Award and presidential citation during the 44th Trade day\nApril 2008\nEstablishment of SolarPark Korea Co., Ltd.(Previously SolarWorl Korea Co., Ltd)\nEstablished as a 50/50 JV with SolarWorld AG\nSeptember 2008\nConstruction of Gochang Solar Park(15MWp) completed\nNovember 2008\nSolarPark Korea completes the first stage construction of its module production factory (annual capacity 60 MW)\nSeptember 2009\nSolarpark Korea completes the second stage construction of its module production factory (annual capacity 90 MW)\nFebruary 2010\nConstruction of the Inline Mechanics Co., Ltd. factory completed\nApril 2010\nSolarPark Korea completes the third stage construction of its module production factory (annual capacity 100 MW)\n'Total capacity : 250 MW'\nOctober 2010\nIEC 61215, 61730-1, 61730-2 certifications received\nNovember 2010\nSolarPark Korea is awarded the Ston Tower Industrial Medal for achieving 300 million dollars in exports during the 47th Trade Day\nJune 2011\nSolarWorld AG's 50% share of SolarPark Korea is acquired by SolarPark Korea.\nSolarPark Korea now owns 100% of shares\nSeptember 2011\nISO 9001 & ISO 14001 certifications received\nApril 2012\nConstruction of second module production factory (annual capacity : 300 MW + 50 MW) completed\n'Total capacity : 600 MW, 5th largest production capacity in Asia (excluding Chinese manufacturers)'\n'July 2012\nMerger of the 3 companies; SolarPark Korea Co., Ltd., SolarPark Co., Ltd., and Inline Mechanics Co., Ltd, completed.\nOct 2012 \nPassed PID test by TUV-SUD\nAutomation in production.\nSolarPark Korea espouses automation in production to achieve consistent high-quality, high-volume and cost-competitive output. Its module production lines achieve a capacity-per-employee of 0.83 MW.\nSolarPark Korea's production lines comprise machines from equipment makers such as Somont, 3S, Berger Lichttechnik, Pasan and Schleich. Equipment integration is provided by affiliate Inline Mechanics.", "Engineering,_Manufacturing": 0.9927498698, "qwen": "Yes"}
{"id": "64689502", "revid": "20483999", "url": "https://en.wikipedia.org/wiki?curid=64689502", "title": "Yiyang High-Tech Industrial Development Zone", "text": "Yiyang High-Tech Industrial Development Zone (; abbr: YYHTZ) is a national high-tech industrial zone in Yiyang, Hunan, China. Its area is . It traces its origins to the former \"Chaoyang Economic Development Zone\" , founded in 1994. It was renamed to the present name, meanwhile the zone was upgraded to one of first batch of provincial HTZs. In 2011, it became a national HTZs approved by the State Council of China. Its four major industries are new materials, new energy, advanced manufacturing and biomedicine.", "Engineering,_Manufacturing": 0.9978457093, "qwen": "Yes"}
{"id": "13506220", "revid": "30164433", "url": "https://en.wikipedia.org/wiki?curid=13506220", "title": "Thermoplastic vulcanizates", "text": "Thermoplastic vulcanizates (TPV) are dynamically vulcanized alloys consisting mostly of fully cured EPDM rubber particles encapsulated in a polypropylene (PP) matrix. They are part of the thermoplastic elastomer (TPE) family of polymers but are closest in elastomeric properties to EPDM thermoset rubber, combining the characteristics of vulcanized rubber with the processing properties of thermoplastics. There are almost 100 grades in the S portfolio that are used globally in the automotive, household appliance, electrical, construction, and healthcare markets. The name Santoprene was trademarked in 1977 by Monsanto, and the trademark is now owned by Celanese. Similar material is available from Elastron and others.\nOverview.\nTPV was created after several years of research and development aimed at finding new materials for injection-molded tires. Although the search for a new tire material was unsuccessful, it resulted in the development of TPV, which combines the characteristics of vulcanized rubber with the processing properties of thermoplastics. The first sales of developmental products began in 1977, the same year it was registered by Monsanto, and it was fully commercialized in 1981.\nPart of the TPE family of polymers, TPV is the closest in elastomeric properties to EPDM thermoset rubber. TPVs have a combination of elastomeric properties, like compression and tension sets, coupled with aging performance and chemical resistance.\nEarly successes.\nSantoprene TPV had early application successes in the automotive sector, including rack and pinion boots, due to its flex life, fluid resistance, and sealability. In the appliance sector, a dishwasher sump boot made with Santoprene TPV provided good sealing and resistance to heat and fluids. Due to its sealing properties, Santoprene TPV was also successful in the domestic and high-rise construction sectors in applications such as window seals, caster wheels, tubing, and small hose parts, electrical connectors, and coatings for wire and cables. It was also used in the medical industry as a gasket on syringe plungers.\nChemistry.\nSantoprene TPV is a dynamically vulcanized alloy consisting mostly of fully cured EPDM rubber particles encapsulated in a polypropylene (PP) matrix.\nPhotographs made using an atomic force microscope and a scanning electron microscope show a multitude of very small particles, typically no bigger than a couple of microns in diameter. These particles are fully vulcanized rubber (typically EPDM rubber for most Santoprene TPV grades) in a thermoplastic phase (most often PP in the case of Santoprene TPV grades). Fully cross-linked or vulcanized means 98% or above, and because the morphology is \"locked-in,\" it provides stable physical properties. \nProperties.\nDesigned for specific engineered applications, Santoprene TPV grades range from the hardness of 35 Shore A up to 50 Shore D.\nSantoprene TPV grades offer the following: \nApplications.\nSantoprene TPV grades are designed for a broad range of specific engineered applications.\nAutomotive components.\nSantoprene TPV (thermoplastic vulcanization) is used in weather seals, underhood and under-car applications, and interior components. In weather seals, TPV is used as a lightweight alternative to thermoset rubber materials in semi-dynamic and static parts, while in underhood and under-car applications it is well-suited for air ducts, tubing, molded seals, grommets, suspension bellows, cable jacketing, plugs, bumpers, and many other parts. This is due to its sealing performance and resistance to extreme temperatures, chemical exposure, and harsh environments.\nBuilding and construction products.\nIn commercial glazing seals, Santoprene TPV is used for curtain walls, storefronts, architectural windows, and skylight weather seal applications. It is also commonly used in residential glazing seals due to its low air and water infiltration ratings for the life of window and door systems.\nFor road and rail construction projects, Santoprene TPV is used for bridge and parking decks, water stops, rail pads, and other applications.\nIn plumbing, Santoprene TPV is used to create long-term seals, gaskets, and grommets that are resistant to flex fatigue, harsh temperatures, and chemicals. It can be used in a variety of sealing applications including pipe seals, bridge expansion joints and curtain walls, parts for potable water, and pipe seals for sewer and drainage.\nHousehold appliance parts.\nSantoprene TPV is used in washing machines, dryers, dishwashers, refrigerators, small appliances, and floor care. Its properties enable it to be used in a range of parts including pump seals, hoses, couplings, vibration dampeners, drum rollers, knobs, and controls.\nElectrical components.\nSantoprene TPV is used in wiring connectors to make watertight seals with electrical and thermal resistance, insulation for high voltage applications, and flexibility even at low temperatures to −60 °C.\nIt is used in industrial wire and cable connectors and low-voltage industrial cable applications that include insulation and jackets, in addition to consumer wire and cable use.\nFor electrical components, Santoprene TPV can be used for watertight seals, enabling connectors to be insert-molded to cable jacketing, producing a single integral part.\nProcessing.\nSantoprene TPV can be processed using conventional thermoplastic processes such as injection molding, blow molding, and extrusion. Manufacturing a part using Santoprene TPV, in contrast to rubber, is less complex. Santoprene TPV is ready to use and does not need to be compounded with different ingredients such as reinforcing fillers (carbon black, mineral fillers), stabilizers, plasticizing oils, and curing systems.\nCompared to processing rubber, thermoplastic processing of Santoprene TPV can deliver shorter cycle times, a higher part output per hour, and the reuse of scrap produced during processing. This can result in part cost reduction, less tooling/machinery, lower scrap costs, and optimization of material logistic costs compared to rubber.\nAfter a short drying period, TPV pellets are automatically transferred to the molding machine or extrusion line. Cycle times can be significantly faster because the parts do not have to cure in the mold, which is typically two to three minutes for rubber. The TPV part only has to cool, typically about 30 seconds, and then it can be removed from the mold or cooled in water.\nProcessing options.\nInjection molding: Santoprene TPV grades can be processed using conventional thermoplastics injection-molding equipment at reduced cycle times compared to thermoset rubber. TPV flexibility allows for greater freedom of mold design where undercuts are employed.\nInsert molding: Insert molding consists of placing a preformed substrate into the mold and injecting TPV around or over it. If the insert and the TPV are compatible materials, a melt bond occurs at the interface between the two materials. The strength of this bond is affected by several factors, including interface temperature, cleanliness of the insert, and melt temperature of the TPV.\nTwo-shot injection molding: TPV can be combined with polymers through several types of multi-shot injection molding processes. By combining multiple materials, a wide variety of parts applications, such as a hard/soft combination, can be achieved. The process produces both a finished part and a substrate during each cycle. Two-shot molding is more efficient than insert molding because no handling of the substrate is required.\nBlow molding: Santoprene TPV can be blow molded in a single layer, multi-layer, exchange blow, sequential 3D, suction blow, flashless extrusion blow, injection blow, and press-blow molding processes.\nExtrusion: Santoprene TPV is easy to extrude into single and complex profiles. These materials can also be coextruded to yield a part with both rigid and soft components.\nThermoforming: The thermoforming properties of Santoprene TPV are similar to acrylonitrile butadiene styrene (ABS) and exhibit good melt strength, which provides uniform and predictable sag characteristics during heating. When producing a sheet for thermoformed parts, key attributes of Santoprene TPV are maintained, including colorability, impact resistance, weatherability, chemical resistance, non-skid, and matte surface in appearance and feel.\nRecycling.\nSantoprene TPV can contribute to a reduction in overall waste in the manufacturing process as scrap produced during processing can be recycled. Material that has been recycled – even from old parts – exhibits properties almost as good as virgin material as an article in “Design News” magazine reported on May 5, 2003.\nAccording to the article: ", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "65795029", "revid": "1163531482", "url": "https://en.wikipedia.org/wiki?curid=65795029", "title": "Gas-assisted injection molding", "text": "Gas-assisted injection molding is a molding process where an inert gas is injected into the melted plastic pushing it further into the mold and resulting in hollow parts.\nBasic concept.\nThe basic concept of the gas-assisted molding process is quite similar to the regular injection molding process. In gas-assisted molding, the plastic material is injected into the mold cavities like the regular injection molding process but only up to 70%~80% of the mold volume. The melted plastic in contact with the mold walls begins to solidify, then nitrogen gas is injected into the mold through strategically designed and placed gas inlets, providing pressure that pushes the plastic into the mold extremities. The path of the bubble is controlled by taking the path of least resistance through the hottest, least viscous plastic, which keeps it centered from the colder walls of the mold. Finally the molded part is ejected like the regular injection molding process.\nAdvantages.\nThis process forms hollow parts that are cheaper than traditionally injection molded equivalents. Molded parts also cool faster in this process. There is also usually less shrinkage as the thicker wall sections are hollow.\nSome of the benefits of this process are:\nDisadvantages.\nThis molding technique is very difficult to apply to multi-cavity molds, especially if the cavity sizes are dissimilar. Clear or transparent plastic materials are an inappropriate option for this technique as the cosmetic-appearance can deteriorate.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "65795802", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=65795802", "title": "Deep hole drilling", "text": "In the field of manufacturing technology, deep hole drilling refers to the drilling of bore holes with high length-to-diameter ratios.\nDefinition of deep hole drilling.\nAccording to the VDI Standard 3210, deep hole drilling processes are manufacturing processes for the machining of bore holes with diameters between D = 0.2...2000 mm and whose drilling depth is usually greater than three times the diameter. For small diameters, length-to-diameter ratios of up to l/D ≤ 100 can be achieved, in special cases even up to l/D = 900. With large diameters, the l/D ratio is usually limited by the travel or the bed length of the deep hole drilling machine.\nDeep hole drilling.\nDeep hole drilling also differs from normal drilling in that, depending on the drilling process and the drilling diameter, cooling lubricant must be pumped to the cutting edges in large quantities and under high pressure. This ensures good cooling and at the same time good lubrication of the contact areas between the workpiece and the cutting edge of the tool on the one hand and the workpiece and guide pads of the tool on the other. In addition, the cooling lubricant leads to the constant removal of chips from the cutting zone, which makes surface-damaging and time-consuming chip removal strokes unnecessary and therefore improves the quality of the borehole and the productivity of the processes. For the production of deep holes, two different tool types are distinguished. On the one hand, there are tools with an asymmetrical single cutting-edge design. These deep hole drilling tools include single-lip deep hole drills, the single-tube system (BTA deep-hole drilling) and the double-tube system (ejector deep-hole drilling), which are referred to as the \"classic\" deep hole drilling processes. On the other hand, there are tools with symmetrically arranged cutting edges. These include spiral deep hole drilling tools and double-lip deep hole drilling tools, which can also be assigned to the deep drilling processes due to the drilling depths to be achieved with them. Deep Hole drilling was made originally in china.\nThe mentioned tool types differ with regard to the realizable diameter range, the achievable l/D ratios, the surface quality and they're productivity. Symmetrical tools can only be used in the small diameter range of D = 0.2 ... 32  mm to produce holes with an l/D ratio up to a maximum of l/D = 85, the standard is an l/D ratio of l/D = 30. With asymmetrical tools, holes in the diameter range of D = 0.5...2000  mm can be produced and the upper limit of the l/D ratio is usually limited by the machine dimensions. The figure shows selected deep hole drilling methods with their usual application diameters, whereby it becomes clear that deep hole drilling methods do not compete with each other in all diameter ranges. The advantage of the symmetrically designed tools compared to the \"classical\" deep hole drilling tools in the small diameter range is the feasibility of significantly higher feeds f, which can be 6 times higher compared to the usual values for single-lip deep hole drilling.\nIn addition to the high l/D ratio, the \"classic\" deep hole drilling methods are characterized by high productivity and high surface quality compared to the conventional drilling methods with twist drills. The high drilling quality is characterized by low surface roughness, small diameter deviations and a high geometrical accuracy. Important for the good surface quality is the asymmetrical design of the deep hole drilling tools. The \"classical\" tools for single-lip deep hole drilling, BTA deep hole drilling and ejector deep hole drilling are, with a few exceptions, designed asymmetrically and have a secondary cutting edge (circular grinding chamfer) and guide pads. Due to this design features, a certain amount of the cutting forces during the process is transferred via the guide pads to the bore hole wall. These force components at the tool head are supported at the produced borehole wall and thus guide the tool in the bore hole itself. The distribution of the process forces during deep hole drilling is therefore different from conventional drilling, where the forces are largely absorbed by the tool shank and thus by the machine spindle. Due to the process force distribution to bore hole wall in deep hole drilling, the drill guides itself and thus the process benefits from a comparatively low straightness deviation. The \"support\" of the guide pads on the borehole wall also results in a forming process that (ideally) smooths the bore hole wall. Due to this forming process the surface roughness caused by the engagement of the cutting edges during drilling can be decreases by about 70%. Thus very high surface qualities with bore hole tolerances of IT 9 to IT 7 can be achieved by deep hole drilling processes. Subsequent steps to improve the surface quality of the bore hole can often be reduced or eliminated completely. A further advantage is the low burr formation for trough holes and for over-drilling cross holes. Due to the high surface quality combined with a high productivity, the use of deep hole drilling methods can be economical even at low drilling depths.\nDeep hole drilling methods.\nSingle-lip deep hole drilling.\nSingle-lip deep hole drilling is usually used to produce holes in the diameter range of D = 0.5...40 mm. This range of application is currently limited at the lower end by the manufacturing technology to realize the coolant channels inside the tool and the increasing challenges in grinding technology with decreasing tool diameters. The upper limit results from the more economical use of alternative deep hole drilling methods. Characteristic for single-lip deep hole drilling is the internal coolant supply through one kidney-shaped or two circular cooling channels. The chip/coolant mixture is discharged in a v-shaped longitudinal groove on the tool, the so-called gullet. The coolant mass flow is the only transport mechanism for removing the chips. For this reason, a diameter-dependent high-pressure coolant supply is necessary. The general structure of single-lip tools is divided into three parts: the drill head, the shank and the clamping sleeve. Usually the drill head is joined to the shank by brazing. The clamping sleeve is the clamping element of the tool and forms the interface to the tool holder and thus to the machine tool. Solid carbide tools are often used for smaller tool diameters and tools with a high-performance design. With these more powerful tools, the drill head and the shank are made of a single carbide rod. The drill head is usually made of carbides of the ISO cutting application group K 10 to K 20 and is coated if required. In special applications, PCD, cermets, ceramics or high-speed steels are also used. The choice of the drill head geometry is made depending on the existing machining situation. In this respect, a distinction is made between different cutting edge angles and the circumferential shape of the guide pads. With the usual standard grinding for single-lip drills, the main cutting edge is divided into an outer and an inner cutting edge, which differ in different cutting edge angles depending on the bore hole diameter. The choice of the circumferential shape, i.e. the number and arrangement of the guide pads on the circumference of the single-lip drill, is also important. Compared to conventional drilling with twist drills, single-lip drilling is characterized by its suitability and high process reliability with large length-to-diameter ratios. In addition, single-lip drilling achieves comparatively high bore hole qualities, which can reduce the need for post-processing.\nTools\nAs can be seen in the pictures, a single-lip deep hole drill consists of a tool holder, a shank and the drill head (usually carbide). As far as the design is concerned, it can be generally said that the shank is a few 1/10th of a millimeter to 1 millimeter smaller than the drill head. It can also be seen that approximately 1/4 of the shank consists of a grove, in which the coolant flow flushes the chips out of the bore hole. The cutting head itself carries guide surfaces which are in contact with the bore hole wall and guide the drill. Conventional twist drill on the other hand are usually guided by the axis of the machine tool.\nThe actual cutting edge is asymmetrically arranged and runs from the cutting edge corner via the tip to the centre of the drill. The tool thus works with a single cutting edge. The cutting forces, which are not cancelled out because of the asymmetrical design, are supported on the bore hole wall. The chips produced at the cutting edge are surrounded by coolant from the outside and then flushed away from the cutting zone through the grove in the shank. Up to a diameter of approx. 10 mm the tools have one cooling channel, for larger diameters two or more channels are used.\nBTA deep hole drilling.\nThe disadvantages of single-lip deep hole drilling, such as the contact of the chips with the generated bore hole surface or the low torsional moment, were the motivation to develop a modified deep hole drilling method that avoids these problems and retains the good properties. As a result of the above, a new deep hole drilling method was developed around 1940, which was given the name BTA deep hole drilling in the early 1950s.\nBTA stands for \"Boring and Trepanning Association\" which was dominated by the now liquidated company Gebrüder Heller in Bremen Germany. Under their leadership, the new process was created during the Second World War by combining their own developments with those of Burgsmüller and Beisner. Burgsmüller replaced the grooved drill shaft used until then by a tube with a closed cross-section, which was more torsionally rigid, and for the first time conveyed the chips through the inside of the tube. Burgsmüller used a double-edged tool and an air-oil mixture, which is nowadays used in production with minimum quantity lubrication. Beisner improved the tool design and introduced oil as cooling lubricant. Heller, which was the first company to introduce carbide-tipped single-lip deep hole drilling tools, had the patent for the cutting edge/guide pad constellation which was then also used for the BTA tools.\nDuring the machining process, the coolant is fed to the cutting zone, as shown in the figure, through the ring gap between the hole produced and the drill tube with the aid of the drilling oil supply unit (BOZA). The BOZA also seals between the workpiece and the drill tube. For this purpose, it has a conical rotating workpiece holder which is directed towards the workpiece and is pressed against the workpiece with high pressure. This centres the workpiece and creates a sealing contact surface. In most cases, the rear side of the BOZA is sealed by a stuffing box, which also guides the drill tube. In the BOZA, the tapping bush is usually integrated, which means that working with a pilot bore hole in the BTA process is rarely necessary.\nTools\nThe chips are removed through the openings integrated in the drilling head with the aid of the cutting oil flow. Therefore, the openings are called \"chip mouth\". In this way, the chips can be removed without contact to the bore hole wall. Due to the circular cross section of the tool and the drill tube, the process has a higher torsional resistance moment compared to single-lip deep hole drilling, which allows a significantly higher cutting performance to be achieved. The BTA process is used for bore hole diameters of D = 6...2000 mm. For industrial processes it is used in a range from approx. D = 16 mm. It is possible to manufacture BTA drill heads with a diameter of D ≤ 6 mm, but there is no known application case until today.\nEjector deep hole drilling.\nThe ejector deep hole drilling is used in a diameter range of approx. D = 18 ... 250 mm. It is a variant of the BTA process in which the drill heads used are structurally comparable to the BTA tool system. The only difference are additional coolant outlets on the circumference of the tool. The coolant is supplied through the ring space between the drill tube and the inner tube, which also gives the process the name two-tube process. The coolant emerges laterally from the already mentioned coolant outlets, flows around the drill head and flows back into the inner tube transporting the produced chips. Part of the coolant is fed directly into the inner tube via a ring nozzle. This creates a negative pressure (ejector effect) at the chip mouth, which facilitates the backflow in the inner tube. The system can be operated via an external high-pressure pump or the internal coolant supply of the machine. Since, in contrast to the BTA process, no sealing against escaping coolant is required, the ejector process can also be used on conventional lathes and machining centres. As the pipe cross-section through which the chips are to be removed is reduced by the double tube system, the cutting capacity is lower than with the BTA process. For this reason, lower cutting speeds are usually selected for ejector deep hole drilling. In addition, the lower rigidity is accompanied by poorer concentricity properties (IT9 to IT11).\nA prerequisite for the implementation of the process is the use of a connecting piece which is inserted into the turret holder of the lathe or the spindle of the machining centre. Through this connection piece, the coolant is fed from the connected pump unit into the ring gap between the inner and outer tube. To enable this function, two different versions are available. A rotating connection piece is required for machining centres, and a non-rotating connection piece for lathes. The required installation space must be taken into account when selecting the machine tool.\nTools\nThe design of the tools for ejector deep hole drilling is almost identical to that of the BTA deep hole drilling tools. The additional coolant discharge outlets are shown in the illustrations.\nMethods associated with deep hole drilling.\nIn addition to the classical deep hole drilling methods, there are a number of other methods for the final processing of deep holes. The hole can be post-processed with regard to their surface finish or can serve as a basis for machining complex and non-cylindrical contours.\nInternal profiling.\nFor various reasons, there are components with deep holes whose inner contours are rotationally symmetrical but not uniformly cylindrical. Such components can have contours without undercuts, e.g. for centrifugal casting moulds or conical bores in extruder cylinders, and with undercuts, e.g. for propeller shafts or landing gears. To produce such chamber pockets, high quality pre-drilling is required. If the radially extendable cutting tool holder is controlled via an NC axis and connected to the NC bore slide of the deep hole drilling machine, it is almost possible to produce any bore hole wall contour in one cut over the entire contour length. The position of the cutting edge can be modified by an axial displacement, e.g. by using an internal thrust tube. In addition, the guide pads can also be adjusted hydraulically. Since the guide bore has already been maschined after the first cutting step for the so-called long chamber method, the guide pads must also be radially adjustable to support the tool for larger chambers. As an alternative to this method, the so-called short-chamber method does not require extendable guide pads, as the tool is only seated in the pre-drilled guide hole.\nSkiving and smooth rolling.\nSkiving improves the roundness and the dimensional accuracy of the bore hole diameter. The process creates an open surface profile, which is particularly suitable for subsequent machining processes such as smooth rolling or honing. In the field of machining hydraulic cylinders and cylinder liners, skiving and smooth rolling is considered a manufacturing process related to deep hole drilling, although it has a cutting and also a forming component. The reason for this is the wide use of combined skiving and smooth rolling tools.\nSingle edge reaming.\nAnother machining process to increase the surface quality and dimensional accuracy of a bore hole is the use of single-bladed reamers. Reaming is the ountersinking of a pre-drilled hole, where the tool is supported by the guide pads themselves. Therefore, the tool geometry of these reamers is very similar to single-lip drills. The difference to single-lip deep hole drilling with low cutting depth is the usually missing circumferential chamfer, a long side cutting edge parallel to the milling axis and the low coolant volumes and pressures.\nDeep hole drilling machines.\nFor machining with deep hole drilling processes or processes associated with deep hole drilling, deep hole drilling machines are mainly used as standard (multi-purpose) or special machines. Gun drills are an archetypal example. Often single-lip deep hole drills are used on machining centres for the production of holes with smaller drilling depths (up to approx. 40 × D).\nEjector drilling is mainly used on conventional machine tools. Since deep hole drilling has a high productivity, only comparatively powerful machines are used. Basically, a coolant system is required that provides coolant with (compared to other drilling methods) above-average volume flow at higher pressures.\nA deep hole drilling system consists of the deep drilling machine and the coolant tank with further peripheral equipment for coolant preparation and chip handling.\nThe ejector drilling process was developed as deep hole drilling technology which can be used on conventional machine tools. The use of single-lip deep hole drilling is particularly common on machining centres in series production.\nOn the right you can see schematic drawings of conventional deep hole drilling machines.\nLiterature.\nVDI – The Association of German Engineers guidelines", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "65804492", "revid": "10728040", "url": "https://en.wikipedia.org/wiki?curid=65804492", "title": "Pressure bag moulding", "text": "Pressure bag moulding is a process for moulding reinforced plastics. This process is related to vacuum bag molding.\nProcedure.\nA solid female mold is used along with a flexible male mold. The reinforcement is placed inside the female mold with just enough resin to permit the fabric to stick in place (wet lay-up). A measured amount of resin is then liberally brushed indiscriminately into the mold and the mold is then clamped to a machine that includes the male flexible mold. Then, the flexible male membrane is inflated with heated compressed air or possibly steam. The female mold can also be heated. Excess resin is forced out along with trapped air. Due to the lower cost of unskilled labor, this method is used extensively in the production of composite helmets. For a helmet bag moulding machine, cycle times vary from 20 to 45 minutes, but if the molds are heated, the finished shells require no further curing.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "65804516", "revid": "36603264", "url": "https://en.wikipedia.org/wiki?curid=65804516", "title": "Autoclave moulding", "text": "Autoclave moulding is an advanced composite manufacturing process.\nProcedure.\nIt is a process that uses a two-sided mould set that forms both surfaces of the panel. On the upper side is a flexible membrane made from silicone or an extruded polymer film such as nylon and on the lower side is a rigid mould. Reinforcement materials can be placed manually or robotically. They involve continuous fibre forms fashioned into textile constructions. Usually, they are pre-impregnated with the resin in the form of prepreg fabrics or unidirectional tapes. In some situations, a film of resin is placed upon the lower mould, and dry reinforcement is placed above. The upper mould is installed, and the vacuum is applied to the mould cavity. The assembly is placed into an autoclave. This process is generally performed at both elevated pressure and elevated temperature. The use of elevated pressure facilitates a high fibre volume fraction and low void content for maximum structural efficiency.", "Engineering,_Manufacturing": 1.0000078678, "qwen": "Yes"}
{"id": "60516419", "revid": "11498870", "url": "https://en.wikipedia.org/wiki?curid=60516419", "title": "Tellurium copper", "text": "Tellurium copper is an alloy of copper and tellurium. Tellurium improves the machinability of copper.\nOverview.\nTellurium is usually added to copper to improve machinability (\"free cutting\"). ASTM specification B301 has 0.5% tellurium; at concentrations of up to 0.75% machinability is improved while electrical conductivity and hot working behavior is maintained. Mechanical properties are similar to \"tough pitch copper\", while machinability is similar to brass - the hardness of the alloy is increased by precipitation of the copper telluride: weissite.\nTellurium copper is not suited to welding, but it can be welded with gas shielded arc welding or resistance welding. It can be readily soft soldered, silver soldered, or brazed.\nTellurium copper can be used as the electrode in electrical discharge machining (EDM) - the alloy is used to replace copper when grinding wheel loading occurs during fine finishing of the electrode - the alloy retains the properties of copper in the EDM process.\nPhase diagram.\nCopper forms tellurides. These include Cu4Te, Cu2Te (m.p. 1125 °C), and CuTe. A eutectic forms at 71% (mol) Te, (m.p. 340 °C). Between 4.3 and 30% (mol) Te there is stratification between Cu and Cu2Te.", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "60550474", "revid": "32329748", "url": "https://en.wikipedia.org/wiki?curid=60550474", "title": "List of automobile manufacturers of Canada", "text": "This is a list of notable automobile manufacturers with articles on Wikipedia by country. It is a subset of the list of automobile manufacturers for manufacturers based in Canada. It includes companies that are in business as well as defunct manufacturers.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "38345915", "revid": "3190495", "url": "https://en.wikipedia.org/wiki?curid=38345915", "title": "Micrometer adjustment nut", "text": "On a manual milling machine, the micrometer adjustment nut limits the depth to which the cutting tool may plunge into the workpiece. \nThe nut is located on a threaded rod on the mill head. The machine operator moves it up or down by rotating it clockwise (to move it down) or counter-clockwise (to move it up). Moving the nut down increases the depth to which the cutting tool may plunge into the workpiece. Moving the nut up reduces the depth to which the cutting tool may plunge into the workpiece.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "38355554", "revid": "1544984", "url": "https://en.wikipedia.org/wiki?curid=38355554", "title": "Partnerized inventory management", "text": "Partner-optimized inventory management, also known as partnerized inventory management or sometimes just the abbreviation PIM is an inventory management technique or model often used in deterministic inventory systems in which a significant portion of the total inventory regularly becomes stochastic in nature, due to slowing and/or low demand such as is typical in heavy machinery and construction equipment where the products themselves are extremely durable and have long lives in the field. Inventory in these cases needs to be maintained for an extended time to allow for repairs and product support perhaps as much as two or more decades after a manufacturer has ceased production.\nTraditional inventory management techniques break down in cases where a manufacturer maintains inventory to supply future maintenance of their in-service equipment. As demand for goods approaches zero, liquidation of inventory is indicated in most revenue management models. Zero inventory to service products in the field, however, fails the organization in other business areas. Possible costs to manufacture replacement inventory and the harder-to-calculate costs of customer confidence erosion can be greater over time than the immediate financial concerns that are remedied by liquidating inventory entirely by scrapping or discarding it as waste.\nWhile scrapping returns inventory to a state of raw materials, Partner-Optimized Inventory Management (PIM) returns inventory to the market as intermediate goods to be used in production of other goods or non-capital spare parts. An organization that uses the PIM model mitigates the immediate pinch point caused by inventory reduction by retaining as-needed mutual access to inventory through the marketplace for an indeterminate time rather than losing access immediately and irrevocably through scrapping or discarding the inventory as waste.", "Engineering,_Manufacturing": 0.9992188811, "qwen": "Yes"}
{"id": "38360943", "revid": "1170508415", "url": "https://en.wikipedia.org/wiki?curid=38360943", "title": "Milling (machining)", "text": "Milling is the process of machining using rotary cutters to remove material by advancing a cutter into a workpiece. This may be done by varying directions on one or several axes, cutter head speed, and pressure. Milling covers a wide variety of different operations and machines, on scales from small individual parts to large, heavy-duty gang milling operations. It is one of the most commonly used processes for machining custom parts to precise tolerances.\nMilling can be done with a wide range of machine tools. The original class of machine tools for milling was the milling machine (often called a mill). After the advent of computer numerical control (CNC) in the 1960s, milling machines evolved into \"machining centers\": milling machines augmented by automatic tool changers, tool magazines or carousels, CNC capability, coolant systems, and enclosures. Milling centers are generally classified as vertical machining centers (VMCs) or horizontal machining centers (HMCs).\nThe integration of milling into turning environments, and vice versa, began with live tooling for lathes and the occasional use of mills for turning operations. This led to a new class of machine tools, multitasking machines (MTMs), which are purpose-built to facilitate milling and turning within the same work envelope.\nProcess.\nMilling is a cutting process that uses a milling cutter to remove material from the surface of a work piece. The milling cutter is a rotary cutting tool, often with multiple cutting points. As opposed to drilling, where the tool is advanced along its rotation axis, the cutter in milling is usually moved perpendicular to its axis so that cutting occurs on the circumference of the cutter. As the milling cutter enters the work piece, the cutting edges (flutes or teeth) of the tool repeatedly cut into and exit from the material, shaving off chips (swarf) from the work piece with each pass. The cutting action is shear deformation; material is pushed off the work piece in tiny clumps that hang together to a greater or lesser extent (depending on the material) to form chips. This makes metal cutting somewhat different (in its mechanics) from slicing softer materials with a blade.\nThe milling process removes material by performing many separate, small cuts. This is accomplished by using a cutter with many teeth, spinning the cutter at high speed, or advancing the material through the cutter slowly; most often it is some combination of these three approaches. The speeds and feeds used are varied to suit a combination of variables. The speed at which the piece advances through the cutter is called feed rate, or just feed; it is most often measured as distance per time (inches per minute [in/min or ipm] or millimeters per minute [mm/min]), although distance per revolution or per cutter tooth are also sometimes used.\nThere are two major classes of milling process:\nMilling cutters.\nMany different types of cutting tools are used in the milling process. Milling cutters such as end mills may have cutting surfaces across their entire end surface, so that they can be drilled into the work piece (plunging). Milling cutters may also have extended cutting surfaces on their sides to allow for peripheral milling. Tools optimized for face milling tend to have only small cutters at their end corners.\nThe cutting surfaces of a milling cutter are generally made of a hard and temperature-resistant material, so that they wear slowly. A low cost cutter may have surfaces made of high speed steel. More expensive but slower-wearing materials include cemented carbide. Thin film coatings may be applied to decrease friction or further increase hardness.\nThere are cutting tools typically used in milling machines or machining centers to perform milling operations (and occasionally in other machine tools). They remove material by their movement within the machine (e.g., a ball nose mill) or directly from the cutter's shape (e.g., a form tool such as a hobbing cutter).\nAs material passes through the cutting area of a milling machine, the blades of the cutter take swarfs of material at regular intervals. Surfaces cut by the side of the cutter (as in peripheral milling) therefore always contain regular ridges. The distance between ridges and the height of the ridges depend on the feed rate, number of cutting surfaces, the cutter diameter. With a narrow cutter and rapid feed rate, these revolution ridges can be significant variations in the surface finish.\nThe face milling process can in principle produce very flat surfaces. However, in practice the result always shows visible trochoidal marks following the motion of points on the cutter's end face. These revolution marks give the characteristic finish of a face milled surface. Revolution marks can have significant roughness depending on factors such as flatness of the cutter's end face and the degree of perpendicularity between the cutter's rotation axis and feed direction. Often a final pass with a slow feed rate is used to improve the surface finish after the bulk of the material has been removed. In a precise face milling operation, the revolution marks will only be microscopic scratches due to imperfections in the cutting edge.\nGang milling refers to the use of two or more milling cutters mounted on the same arbor (that is, ganged) in a horizontal-milling setup. All of the cutters may perform the same type of operation, or each cutter may perform a different type of operation. For example, if several workpieces need a slot, a flat surface, and an angular groove, a good method to cut these (within a non-CNC context) would be gang milling. All the completed workpieces would be the same, and milling time per piece would be minimized.\nGang milling was especially important before the CNC era, because for duplicate part production, it was a substantial efficiency improvement over manual-milling one feature at an operation, then changing machines (or changing setup of the same machine) to cut the next op. Today, CNC mills with automatic tool change and 4- or 5-axis control obviate gang-milling practice to a large extent.\nEquipment.\nMilling is performed with a milling cutter in various forms, held in a collet or similar which, in turn, is held in the spindle of a milling machine.\nTypes and nomenclature.\nMill orientation is the primary classification for milling machines. The two basic configurations are vertical and horizontal – referring to the orientation of the rotating spindle upon which the cutter is mounted. However, there are alternative classifications according to method of control, size, purpose and power source.\nMill orientation.\nVertical.\nIn the vertical milling machine the spindle axis is vertically oriented. Milling cutters are held in the spindle and rotate on its axis. The spindle can generally be lowered (or the table can be raised, giving the same relative effect of bringing the cutter closer or deeper into the work), allowing plunge cuts and drilling. The depth to which blades cut into the work can be controlled with a micrometer adjustment nut. There are two subcategories of vertical mills: the bed mill and the turret mill.\nTurret mills are generally considered by some to be more versatile of the two designs.\nA third type also exists, a lighter, more versatile machine, called a mill-drill. The mill-drill is a close relative of the vertical mill and quite popular in light industry; and with hobbyists. A mill-drill is similar in basic configuration to a very heavy drill press, but equipped with an X-Y table and a much larger column. They also typically use more powerful motors than a comparably sized drill press, most are muti-speed belt driven with some models having a geared head or electronic speed control. They generally have quite heavy-duty spindle bearings to deal with the lateral loading on the spindle that is created by a milling operation. A mill drill also typically raises and lowers the entire head, including motor, often on a dovetailed (sometimes round with rack and pinion) vertical column. A mill drill also has a large quill that is generally locked during milling operations and released to facilitate drilling functions. Other differences that separate a mill-drill from a drill press may be a fine tuning adjustment for the Z-axis, a more precise depth stop, the capability to lock the X, Y or Z axis, and often a system of tilting the head or the entire vertical column and powerhead assembly to allow angled cutting-drilling. Aside from size, the principal difference between these lighter machines and larger vertical mills is that the X-Y table is at a fixed elevation; the Z-axis is controlled by moving the head or quill down toward the X,Y table. A mill drill typically has an internal taper fitting in the quill to take a collet chuck, face mills, or a Jacobs chuck similar to the vertical mill.\nHorizontal.\nA horizontal mill has the same sort but the cutters are mounted on a horizontal spindle, or arbor, mounted across the table. Many horizontal mills also feature a built-in rotary table that allows milling at various angles; this feature is called a \"universal table\". While endmills and the other types of tools available to a vertical mill may be used in a horizontal mill, their real advantage lies in arbor-mounted cutters, called side and face mills, which have a cross section rather like a circular saw, but are generally wider and smaller in diameter. Because the cutters have good support from the arbor and have a larger cross-sectional area than an end mill, quite heavy cuts can be taken enabling rapid material removal rates. These are used to mill grooves and slots. Plain mills are used to shape flat surfaces. Several cutters may be ganged together on the arbor to mill a complex shape of slots and planes. Special cutters can also cut grooves, bevels, radii, or indeed any section desired. These specialty cutters tend to be expensive. Simplex mills have one spindle, and duplex mills have two. It is also easier to cut gears on a horizontal mill. Some horizontal milling machines are equipped with a power-take-off provision on the table. This allows the table feed to be synchronized to a rotary fixture, enabling the milling of spiral features such as hypoid gears.\nUniversal.\nIs a milling machine with the facility to either have a horizontal spindle or a vertical spindle. The latter sometimes being on a two-axis turret enabling the spindle to be pointed in any direction on desires. The two options may be driven independently or from one motor through gearing. In either case, as the work is generally placed in the same place for either type of operation, the mechanism for the method not being used is moved out of the way. In smaller machines, \"spares\" may be lifted off while larger machines offer a system to retract those parts not in use.\nComparative merits.\nThe choice between vertical and horizontal spindle orientation in milling machine design usually hinges on the shape and size of a workpiece and the number of sides of the workpiece that require machining. Work in which the spindle's axial movement is normal to one plane, with an endmill as the cutter, lends itself to a vertical mill, where the operator can stand before the machine and have easy access to the cutting action by looking down upon it. Thus vertical mills are most favored for diesinking work (machining a mould into a block of metal). Heavier and longer workpieces lend themselves to placement on the table of a horizontal mill.\nPrior to numerical control, horizontal milling machines evolved first, because they evolved by putting milling tables under lathe-like headstocks. Vertical mills appeared in subsequent decades, and accessories in the form of add-on heads to change horizontal mills to vertical mills (and later vice versa) have been commonly used. Even in the CNC era, a heavy workpiece needing machining on multiple sides lends itself to a horizontal machining center, while diesinking lends itself to a vertical one.\nAlternative classifications.\nIn addition to horizontal versus vertical, other distinctions are also important:\nAlternative terminology.\nA milling machine is often called a mill by machinists. The archaic term miller was commonly used in the 19th and early 20th centuries.\nSince the 1960s there has developed an overlap of usage between the terms milling machine and machining center. NC/CNC machining centers evolved from milling machines, which is why the terminology evolved gradually with considerable overlap that still persists. The distinction, when one is made, is that a machining center is a mill with features that pre-CNC mills never had, especially an automatic tool changer (ATC) that includes a tool magazine (carousel), and sometimes an automatic pallet changer (APC). In typical usage, all machining centers are mills, but not all mills are machining centers; only mills with ATCs are machining centers.\nComputer numerical control.\nMost CNC milling machines (also called \"machining centers\") are computer controlled vertical mills with the ability to move the spindle vertically along the Z-axis. This extra degree of freedom permits their use in diesinking, engraving applications, and 2.5D surfaces such as relief sculptures. When combined with the use of conical tools or a ball nose cutter, it also significantly improves milling precision without impacting speed, providing a cost-efficient alternative to most flat-surface hand-engraving work.\nCNC machines can exist in virtually any of the forms of manual machinery, like horizontal mills. The most advanced CNC milling-machines, the multiaxis machine, add two more axes in addition to the three normal axes (XYZ). Horizontal milling machines also have a C or Q axis, allowing the horizontally mounted workpiece to be rotated, essentially allowing asymmetric and eccentric turning. The fifth axis (B axis) controls the tilt of the tool itself. When all of these axes are used in conjunction with each other, extremely complicated geometries, even organic geometries such as a human head can be made with relative ease with these machines. But the skill to program such geometries is beyond that of most operators. Therefore, 5-axis milling machines are practically always programmed with CAM.\nThe operating system of such machines is a closed loop system and functions on feedback.\nThese machines have developed from the basic NC (NUMERIC CONTROL) machines. A computerized form of NC machines is known as CNC machines. A set of instructions (called a program) is used to guide the machine for desired operations. There are over 100 different G-codes and M-codes. Some very commonly used codes, which are used in the program are:\n G00 – rapid traverse\n G01 – linear interpolation of tool\n G02 - circular arc clockwise (cw)\n G03 - circular arc counter-clockwise (ccw)\n G20 - dimensions in inch\n G21 – dimensions in mm\n G28 - return to reference point\n G40 - Tool compensation cancel\n G41 - Tool compensation left\n G42 - Tool compensation right\n G43 - Tool length compensation\n G54 - Select coordinate system #1\n M03 – spindle start (clockwise)\n M04 – spindle start (counter-clockwise)\n M05 - spindle stop\n M06 - tool change\n M08 - coolant on\n M09 - coolant off\n M30 – program end\nVarious other codes are also used. A CNC machine is operated by a single operator called a programmer. This machine is capable of performing various operations automatically and economically.\nWith the declining price of computers and open source CNC software, the entry price of CNC machines has plummeted.\nTooling.\nThe accessories and cutting tools used on machine tools (including milling machines) are referred to in aggregate by the mass noun \"tooling\". There is a high degree of standardization of the tooling used with CNC milling machines, and a lesser degree with manual milling machines. To ease up the organization of the tooling in CNC production many companies use a tool management solution.\nMilling cutters for specific applications are held in various tooling configurations.\nCNC milling machines nearly always use SK (or ISO), CAT, BT or HSK tooling. SK tooling is the most common in Europe, while CAT tooling, sometimes called V-Flange Tooling, is the oldest and probably most common type in the USA. CAT tooling was invented by Caterpillar Inc. of Peoria, Illinois, in order to standardize the tooling used on their machinery. CAT tooling comes in a range of sizes designated as CAT-30, CAT-40, CAT-50, etc. The number refers to the Association for Manufacturing Technology (formerly the National Machine Tool Builders Association (NMTB)) taper size of the tool.\nAn improvement on CAT Tooling is BT Tooling, which looks similar and can easily be confused with CAT tooling. Like CAT Tooling, BT Tooling comes in a range of sizes and uses the same NMTB body taper. However, BT tooling is symmetrical about the spindle axis, which CAT tooling is not. This gives BT tooling greater stability and balance at high speeds. One other subtle difference between these two toolholders is the thread used to hold the pull stud. CAT Tooling is all Imperial thread and BT Tooling is all Metric thread. Note that this affects the pull stud only; it does not affect the tool that they can hold. Both types of tooling are sold to accept both Imperial and metric sized tools.\nSK and HSK tooling, sometimes called \"Hollow Shank Tooling\", is much more common in Europe where it was invented than it is in the United States. It is claimed that HSK tooling is even better than BT Tooling at high speeds. The holding mechanism for HSK tooling is placed within the (hollow) body of the tool and, as spindle speed increases, it expands, gripping the tool more tightly with increasing spindle speed. There is no pull stud with this type of tooling.\nFor manual milling machines, there is less standardization, because a greater plurality of formerly competing standards exist. Newer and larger manual machines usually use NMTB tooling. This tooling is somewhat similar to CAT tooling but requires a drawbar within the milling machine. Furthermore, there are a number of variations with NMTB tooling that make interchangeability troublesome. The older a machine, the greater the plurality of standards that may apply (e.g., Morse, Jarno, Brown & Sharpe, Van Norman, and other less common builder-specific tapers). However, two standards that have seen especially wide usage are the Morse #2 and the R8, whose prevalence was driven by the popularity of the mills built by Bridgeport Machines of Bridgeport, Connecticut. These mills so dominated the market for such a long time that \"Bridgeport\" is virtually synonymous with \"manual milling machine\". Most of the machines that Bridgeport made between 1938 and 1965 used a Morse taper #2, and from about 1965 onward most used an R8 taper.\nCNC pocket milling.\nPocket milling has been regarded as one of the most widely used operations in machining. It is extensively used in aerospace and shipyard industries. In pocket milling the material inside an arbitrarily closed boundary on a flat surface of a work piece is removed to a fixed depth. Generally flat bottom end mills are used for pocket milling. Firstly roughing operation is done to remove the bulk of material and then the pocket is finished by a finish end mill.\nMost of the industrial milling operations can be taken care of by 2.5 axis CNC milling. This type of path control can machine up to 80% of all mechanical parts. Since the importance of pocket milling is very relevant, therefore effective pocketing approaches can result in reduction in machining time and cost.\nNC pocket milling can be carried out mainly by two tool paths, viz. linear and non-linear.\nLinear tool path.\nIn this approach, the tool movement is unidirectional. Zig-zag and zig tool paths are the examples of linear tool path.\nZig-zag.\nIn zig-zag milling, material is removed both in forward and backward paths. In this case, cutting is done both with and against the rotation of the spindle. This reduces the machining time but increases machine chatter and tool wear.\nZig.\nIn zig milling, the tool moves only in one direction. The tool has to be lifted and retracted after each cut, due to which machining time increases. However, in case of zig milling surface quality is better.\nNon-linear tool path.\nIn this approach, tool movement is multi-directional. One example of non-linear tool path is contour-parallel tool path.\nContour-parallel.\nIn this approach, the required pocket boundary is used to derive the tool path. In this case the cutter is always in contact with the work material. Hence the idle time spent in positioning and retracting the tool is avoided. For large-scale material removal, contour-parallel tool path is widely used because it can be consistently used with up-cut or down-cut method during the entire process. There are three different approaches that fall into the category of contour-parallel tool path generation. They are:\nCurvilinear.\nIn this approach, the tool travels along a gradually evolving spiral path. The spiral starts at the center of the pocket to be machined and the tool gradually moves towards the pocket boundary. The direction of the tool path changes progressively and local acceleration and deceleration of the tool are minimized. This reduces tool wear.\nHistory.\n1780-1810.\nMilling machines evolved from the practice of rotary filing—that is, running a circular cutter with file-like teeth in the headstock of a lathe. Rotary filing and, later, true milling were developed to reduce time and effort spent hand-filing. The full story of milling machine development may never be known, because much early development took place in individual shops where few records were kept for posterity. However, the broad outlines are known, as summarized below. From a history-of-technology viewpoint, it is clear that the naming of this new type of machining with the term \"milling\" was an extension from that word's earlier senses of processing materials by abrading them in some way (cutting, grinding, crushing, etc.).\nRotary filing long predated milling. A rotary file by Jacques de Vaucanson, circa 1760, is well known.\nIn 1783, Samuel Rehe invented a true milling machine. In 1795, Eli Terry began using a milling machine at Plymouth Connecticut in the production of tall case clocks. With the use of his milling machine, Terry was the first to accomplish Interchangeable parts in the clock industry. Milling wooden parts was efficient in interchangeable parts, but inefficient in high yields. Milling wooden blanks results in a low yield of parts because the machines single blade would cause loss of gear teeth when the cutter hit parallel grains in the wood. Terry later invented a spindle cutting machine to mass produce parts in 1807. Other Connecticut clockmakers like James Harrison of Waterbury, Thomas Barnes of Litchfield, and Gideon Roberts of Bristol, also used milling machines to produce their clocks.\n1810s–1830s.\nIt is clear that milling machines as a distinct class of machine tool (separate from lathes running rotary files) first appeared between 1814 and 1818. The centers of earliest development of true milling machines were two federal armories of the U.S. (Springfield and Harpers Ferry) together with the various private armories and inside contractors that shared turnover of skilled workmen with them. \nBetween 1912 and 1916, Joseph W. Roe, a respected founding father of machine tool historians, credited Eli Whitney (one of the private arms makers mentioned above) with producing the first true milling machine. By 1918, he considered it \"Probably the first milling machine ever built—certainly the oldest now in existence […].\" However, subsequent scholars, including Robert S. Woodbury and others, have improved upon Roe's early version of the history and suggest that just as much credit—in fact, probably more—belongs to various other inventors, including Robert Johnson of Middletown, Connecticut; Captain John H. Hall of the Harpers Ferry armory; Simeon North of the Staddle Hill factory in Middletown; Roswell Lee of the Springfield armory; and Thomas Blanchard. (Several of the men mentioned above are sometimes described on the internet as \"the inventor of the first milling machine\" or \"the inventor of interchangeable parts\". Such claims are oversimplified, as these technologies evolved over time among many people.)\nPeter Baida, citing Edward A. Battison's article \"Eli Whitney and the Milling Machine,\" which was published in the \"Smithsonian Journal of History\" in 1966, exemplifies the dispelling of the \"Great Man\" image of Whitney by historians of technology working in the 1950s and 1960s. He quotes Battison as concluding that \"There is no evidence that Whitney developed or used a true milling machine.\" Baida says, \"The so-called Whitney machine of 1818 seems actually to have been made after Whitney's death in 1825.\" Baida cites Battison's suggestion that the first true milling machine was made not by Whitney, but by Robert Johnson of Middletown.\nThe late teens of the 19th century were a pivotal time in the history of machine tools, as the period of 1814 to 1818 is also the period during which several contemporary pioneers (Fox, Murray, and Roberts) were developing the planer, and as with the milling machine, the work being done in various shops was undocumented for various reasons (partially because of proprietary secrecy, and also simply because no one was taking down records for posterity).\nJames Nasmyth built a milling machine very advanced for its time between 1829 and 1831. It was tooled to mill the six sides of a hex nut that was mounted in a six-way indexing fixture.\nA milling machine built and used in the shop of Gay & Silver (aka Gay, Silver, & Co) in the 1830s was influential because it employed a better method of vertical positioning than earlier machines. For example, Whitney's machine (the one that Roe considered the very first) and others did not make provision for vertical travel of the knee. Evidently, the workflow assumption behind this was that the machine would be set up with shims, vise, etc. for a certain part design, and successive parts did not require vertical adjustment (or at most would need only shimming). This indicates that early thinking about milling machines was as production and not as toolroom machines.\nIn these early years, milling was often viewed as only a roughing operation to be followed by finishing with a hand file. The idea of \"reducing\" hand filing was more important than \"replacing\" it.\n1840s–1860.\nSome of the key men in milling machine development during this era included Frederick W. Howe, Francis A. Pratt, Elisha K. Root, and others. (These same men during the same era were also busy developing the state of the art in turret lathes. Howe's experience at Gay & Silver in the 1840s acquainted him with early versions of both machine tools. His machine tool designs were later built at Robbins & Lawrence, the Providence Tool Company, and Brown & Sharpe.) The most successful milling machine design to emerge during this era was the , which rather than being a specific make and model of machine tool is truly a family of tools built by various companies on a common configuration over several decades. It took its name from the first company to put one on the market, George S. Lincoln & Company (formerly the Phoenix Iron Works), whose first one was built in 1855 for the Colt armory.\nDuring this era there was a continued blind spot in milling machine design, as various designers failed to develop a truly simple and effective means of providing slide travel in all three of the archetypal milling axes (X, Y, and Z—or as they were known in the past, longitudinal, traverse, and vertical). Vertical positioning ideas were either absent or underdeveloped. The Lincoln miller's spindle could be raised and lowered, but the original idea behind its positioning was to be set up in position and then run, as opposed to being moved frequently while running. Like a turret lathe, it was a repetitive-production machine, with each skilled setup followed by extensive fairly low skill operation.\n1860s.\nIn 1861, Frederick W. Howe, while working for the Providence Tool Company, asked Joseph R. Brown of Brown & Sharpe for a solution to the problem of milling spirals, such as the flutes of twist drills. These were usually filed by hand at the time. (Helical planing existed but was by no means common.) Brown designed a \"universal milling machine\" that, starting from its first sale in March 1862, was wildly successful. It solved the problem of 3-axis travel (i.e., the axes that we now call XYZ) much more elegantly than had been done in the past, and it allowed for the milling of spirals using an indexing head fed in coordination with the table feed. The term \"universal\" was applied to it because it was ready for any kind of work, including toolroom work, and was not as limited in application as previous designs. (Howe had designed a \"universal miller\" in 1852, but Brown's of 1861 is the one considered a groundbreaking success.)\nBrown also developed and patented (1864) the design of formed milling cutters in which successive sharpenings of the teeth do not disturb the geometry of the form.\nThe advances of the 1860s opened the floodgates and ushered in modern milling practice.\n1870s to World War I.\nIn these decades, Brown & Sharpe and the Cincinnati Milling Machine Company dominated the American milling machine field. However, hundreds of other firms also built milling machines at the time, and many were significant in various ways. Besides a wide variety of specialized production machines, the archetypal multipurpose milling machine of the late 19th and early 20th centuries was a heavy knee-and-column horizontal-spindle design with power table feeds, indexing head, and a stout overarm to support the arbor. The evolution of machine design was driven not only by inventive spirit but also by the constant evolution of milling cutters that saw milestone after milestone from 1860 through World War I.\nWorld War I and interwar period.\nAround the end of World War I, machine tool control advanced in various ways that laid the groundwork for later CNC technology. The jig borer popularized the ideas of coordinate dimensioning (dimensioning of all locations on the part from a single reference point); working routinely in \"tenths\" (ten-thousandths of an inch, 0.0001\") as an everyday machine capability; and using the control to go straight from drawing to part, circumventing jig-making. In 1920 the new tracer design of J.C. Shaw was applied to Keller tracer milling machines for die sinking via the three dimensional copying of a template. This made die sinking faster and easier just as dies were in higher demand than ever before, and was very helpful for large steel dies such as those used to stamp sheets in automobile manufacturing. Such machines translated the tracer movements to input for servos that worked the machine leadscrews or hydraulics. They also spurred the development of antibacklash leadscrew nuts. All of the above concepts were new in the 1920s but became routine in the NC/CNC era. By the 1930s, incredibly large and advanced milling machines existed, such as the Cincinnati Hydro-Tel, that presaged today's CNC mills in every respect except for CNC control itself.\nBridgeport milling machine.\nIn 1936, Rudolph Bannow (1897–1962) conceived of a major improvement to the milling machine. His company commenced manufacturing a new knee-and-column vertical mill in 1938. This was the Bridgeport milling machine, often called a ram-type or turret-type mill because its head has sliding-ram and rotating-turret mounting. The machine became so popular that many other manufacturers created copies and variants. Furthermore, its name came to connote any such variant. The Bridgeport offered enduring advantages over previous models. It was small enough, light enough, and affordable enough to be a practical acquisition for even the smallest machine shop businesses, yet it was also smartly designed, versatile, well-built, and rigid. Its various directions of sliding and pivoting movement allowed the head to approach the work from any angle. The Bridgeport's design became the dominant form for manual milling machines used by several generations of small- and medium-enterprise machinists. By the 1980s an estimated quarter-million Bridgeport milling machines had been built, and they (and their clones) are still being produced today. \n1940s–1970s.\nBy 1940, automation via cams, such as in screw machines and automatic chuckers, had already been very well developed for decades. Beginning in the 1930s, ideas involving servomechanisms had been in the air, but it was especially during and immediately after World War II that they began to germinate (see also Numerical control > History). These were soon combined with the emerging technology of digital computers. This technological development milieu, spanning from the immediate pre–World War II period into the 1950s, was powered by the military capital expenditures that pursued contemporary advancements in the directing of gun and rocket artillery and in missile guidance—other applications in which humans wished to control the kinematics/dynamics of large machines quickly, precisely, and automatically. Sufficient R&D spending probably would not have happened within the machine tool industry alone; but it was for the latter applications that the will and ability to spend was available. Once the development was underway, it was eagerly applied to machine tool control in one of the many post-WWII instances of technology transfer.\nIn 1952, numerical control reached the developmental stage of laboratory reality. The first NC machine tool was a Cincinnati Hydrotel milling machine retrofitted with a scratch-built NC control unit. It was reported in \"Scientific American\", just as another groundbreaking milling machine, the Brown & Sharpe universal, had been in 1862.\nDuring the 1950s, numerical control moved slowly from the laboratory into commercial service. For its first decade, it had rather limited impact outside of aerospace work. But during the 1960s and 1970s, NC evolved into CNC, data storage and input media evolved, computer processing power and memory capacity steadily increased, and NC and CNC machine tools gradually disseminated from an environment of huge corporations and mainly aerospace work to the level of medium-sized corporations and a wide variety of products. NC and CNC's drastic advancement of machine tool control deeply transformed the culture of manufacturing. The details (which are beyond the scope of this article) have evolved immensely with every passing decade.\n1980s–present.\nComputers and CNC machine tools continue to develop rapidly. The personal computer revolution has a great impact on this development. By the late 1980s small machine shops had desktop computers and CNC machine tools. Soon after, hobbyists, artists, and designers began obtaining CNC mills and lathes. Manufacturers have started producing economically priced CNCs machines small enough to sit on a desktop which can cut at high resolution materials softer than stainless steel. They can be used to make anything from jewelry to printed circuit boards to gun parts, even fine art.\nStandards.\nNational and international standards are used to standardize the definitions, environmental requirements, and test methods used for milling. Selection of the standard to be used is an agreement between the supplier and the user and has some significance in the design of the mill. In the United States, ASME has developed the standards B5.45-1972 \"Milling Machines\" and B94.19-1997 \"Milling Cutters and End Mills\".\nGeneral tolerances include: +/-0.005\" (~0.1mm) for local tolerances across most geometries, +/-0.010\" (~0.25mm) for plastics with variation depending on the size of the part, 0.030\" (~0.75mm) minimum wall thickness for metals, and 0.060\" (~1.5mm) minimum wall thickness for plastics.", "Engineering,_Manufacturing": 1.0000052452, "qwen": "Yes"}
{"id": "38373876", "revid": "11025703", "url": "https://en.wikipedia.org/wiki?curid=38373876", "title": "Mill finish", "text": "Mill finish is the surface texture (or finish) of metal after it exits a rolling mill, extrusion die, or drawing processes, including sheet, bar, plate, or structural shapes. This texture is usually rough and lacks lustre; it may have spots of oxidation or contamination with mill oil. Most mill finish surfaces are machined or treated with polishing, industrial etching, or some other surface finishing process before they are considered complete.\nThe quality and characteristics of mill finish can vary widely from one mill to another, and even from one lot (set of similar parts all processed consecutively or in a short time) to another. Hot rolled parts are usually dark and dull, their surface oxidized from being hot worked. Extruded products may have die marks running the length of the stock. Other mill finishes are surprisingly smooth and uniform. \nIt is possible for a mill to influence the finish of produced stock. Carefully maintained and polished rollers can increase the smoothness and lustre of their product, and some rolling mills will follow rolling with an annealling process to give the stock a matte finish.", "Engineering,_Manufacturing": 1.0000088215, "qwen": "Yes"}
{"id": "1179028", "revid": "46294397", "url": "https://en.wikipedia.org/wiki?curid=1179028", "title": "Grinding machine", "text": "A grinding machine, often shortened to grinder, is a power tool (or machine tool) used for grinding. It is a type of machining using an abrasive wheel as the cutting tool. Each grain of abrasive on the wheel's surface cuts a small chip from the workpiece via shear deformation.\nGrinding is used to finish workpieces that must show high surface quality (e.g., low surface roughness) and high accuracy of shape and dimension. As the accuracy in dimensions in grinding is of the order of 0.000025  mm, in most applications, it tends to be a finishing operation and removes comparatively little metal, about 0.25 to 0.50  mm depth. However, there are some roughing applications in which grinding removes high volumes of metal quite rapidly. Thus, grinding is a diverse field.\nOverview.\nThe grinding machine consists of a bed with a fixture to guide and hold the workpiece and a power-driven grinding wheel spinning at the required speed. The wheel’s diameter and the manufacturer’s rating determine the speed. The grinding head can travel across a fixed workpiece, or the workpiece can be moved while the grinding head stays in a fixed position.\nFine control of the grinding head or table position is possible using a vernier calibrated hand wheel or using the features of numerical controls.\nGrinding machines remove material from the workpiece by abrasion, which can generate substantial amounts of heat. To cool the workpiece so that it does not overheat and go outside its tolerance, grinding machines incorporate a coolant. The coolant also benefits the machinist as the heat generated may cause burns. In high-precision grinding machines (most cylindrical and surface grinders), the final grinding stages are usually set up so that they remove about 200  nm (less than 1/10000  in) per pass - this generates so little heat that even with no coolant, the temperature rise is negligible.\nTypes.\nThese machines include the:", "Engineering,_Manufacturing": 0.9999870062, "qwen": "Yes"}
{"id": "2877631", "revid": "33011235", "url": "https://en.wikipedia.org/wiki?curid=2877631", "title": "Back end of line", "text": "The back end of line (BEOL) is the second portion of IC fabrication where the individual devices (transistors, capacitors, resistors, etc.) get interconnected with wiring on the wafer, the metalization layer. Common metals are copper and aluminum. \nBEOL generally begins when the first layer of metal is deposited on the wafer. BEOL includes contacts, insulating layers (dielectrics), metal levels, and bonding sites for chip-to-package connections.\nAfter the last FEOL step, there is a wafer with isolated transistors (without any wires). In BEOL part of fabrication stage contacts (pads), interconnect wires, vias and dielectric structures are formed. For modern IC process, more than 10 metal layers can be added in the BEOL.\nSteps of the BEOL:\nBefore 1998, practically all chips used aluminium for the metal interconnection layers.\nThe four metals with the highest electrical conductivity are silver with the highest conductivity, then copper, then gold, then aluminium.\nAfter BEOL there is a \"back-end process\" (also called post-fab), which is done not in the cleanroom, often by a different company.\nIt includes wafer test, wafer backgrinding, die separation, die tests, IC packaging and final test.", "Engineering,_Manufacturing": 1.0000084639, "qwen": "Yes"}
{"id": "2878111", "revid": "233390", "url": "https://en.wikipedia.org/wiki?curid=2878111", "title": "Developable surface", "text": "In mathematics, a developable surface (or torse: archaic) is a smooth surface with zero Gaussian curvature. That is, it is a surface that can be flattened onto a plane without distortion (i.e. it can be bent without stretching or compression). Conversely, it is a surface which can be made by transforming a plane (i.e. \"folding\", \"bending\", \"rolling\", \"cutting\" and/or \"gluing\"). In three dimensions all developable surfaces are ruled surfaces (but not vice versa). There are developable surfaces in four-dimensional space which are not ruled.\nThe envelope of a single parameter family of planes is called a developable surface.\nParticulars.\nThe developable surfaces which can be realized in three-dimensional space include:\nFormally, in mathematics, a developable surface is a surface with zero Gaussian curvature. One consequence of this is that all \"developable\" surfaces embedded in 3D-space are ruled surfaces (though hyperboloids are examples of ruled surfaces which are not developable). Because of this, many developable surfaces can be visualised as the surface formed by moving a straight line in space. For example, a cone is formed by keeping one end-point of a line fixed whilst moving the other end-point in a circle.\nApplication.\nDevelopable surfaces have several practical applications. \nDevelopable Mechanisms are mechanisms that conform to a developable surface and can exhibit motion (deploy) off the surface. \nMany cartographic projections involve projecting the Earth to a developable surface and then \"unrolling\" the surface into a region on the plane. \nSince developable surfaces may be constructed by bending a flat sheet, they are also important in manufacturing objects from sheet metal, cardboard, and plywood. An industry which uses developed surfaces extensively is shipbuilding.\nNon-developable surface.\nMost smooth surfaces (and most surfaces in general) are not developable surfaces. Non-developable surfaces are variously referred to as having \"double curvature\", \"doubly curved\", \"compound curvature\", \"non-zero Gaussian curvature\", etc.\nSome of the most often-used non-developable surfaces are:\nApplications of non-developable surfaces.\nMany gridshells and tensile structures and similar constructions gain strength by using (any) doubly curved form.", "Engineering,_Manufacturing": 0.9997510314, "qwen": "Yes"}
{"id": "2628021", "revid": "44274926", "url": "https://en.wikipedia.org/wiki?curid=2628021", "title": "Punching", "text": "Punching is a forming process that uses a punch press to force a tool, called a \"punch\", through the workpiece to create a hole via shearing. Punching is applicable to a wide variety of materials that come in sheet form, including sheet metal, paper, vulcanized fibre and some forms of plastic sheet. The punch often passes through the work into a die. A scrap slug from the hole is deposited into the die in the process. Depending on the material being punched this slug may be recycled and reused or discarded.\nPunching is often the cheapest method for creating holes in sheet materials in medium to high production volumes. When a specially shaped punch is used to create multiple usable parts from a sheet of material the process is known as blanking. In metal forging applications the work is often punched while hot, and this is called hot punching.\nSlugging is the operation of punching in which the punch is stopped as soon as the metal fracture is complete and metal is not removed but held in hole.\nProcess.\nPunch tooling (punch and die) is often made of hardened steel or tungsten carbide. A die is located on the opposite side of the workpiece and supports the material around the perimeter of the hole and helps to localize the shearing forces for a cleaner edge. There is a small amount of clearance between the punch and the die to prevent the punch from sticking in the die and so less force is needed to make the hole. The amount of clearance needed depends on the thickness, with thicker materials requiring more clearance, but the clearance is always less than the thickness of the workpiece. The clearance is also dependent on the hardness of the workpiece. The punch press forces the punch through a workpiece, producing a hole that has a diameter equivalent to the punch, or slightly smaller after the punch is removed. All ductile materials stretch to some extent during punching which often causes the punch to stick in the workpiece. In this case, the punch must be physically pulled back out of the hole while the work is supported from the punch side, and this process is known as stripping. The hole walls will show burnished area, rollover, and die break and must often be further processed. The slug from the hole falls through the die into some sort of container to either dispose of the slug or recycle it.\nPunching characteristics.\nThe characteristics of punching are:\nGeometry.\nThe workpiece is often in the form of a sheet or roll. Materials for the workpiece can vary, commonly being metals and plastics. The punch and die themselves can have a variety of shapes to create an array of different shaped holes in the workpiece. Multiple punches may be used together to create a part in one step.\nUsually, the punch and die are close to the same dimensions, creating a sheared edge when they meet. A punch that is significantly smaller than the die can be used to produce an \"extruded hole\" where the punch displaces the punched material to the sides, forming a tube perpendicular to the punched sheet.\nEquipment.\nMost punch presses are mechanically operated, but simple punches are often hand-powered. Major components of this mechanical press are the frame, motor, ram, die posts, bolster, and bed. The punch is mounted into the ram, and the die is mounted to the bolster plate. The scrap material drops through as the workpiece is advanced for the next hole. Most common in industry are large computer-controlled punch press, called a CNC. These most commonly are of the 'turret' or 'rail' variety. A turret punch press houses punches and their corresponding dies in a revolving indexed turret, while a rail type punch stores tooling on a back rail out of the way of the workpiece. These machines use hydraulic as well as pneumatic power to press the shape with enough force to shear the metal.\nForces.\nThe punch force required to punch a piece of sheet metal can be estimated from the following equation:\nWhere \"t\" is the sheet metal thickness, \"L\" is the total length sheared (perimeter of the shape), and \"UTS\" is the ultimate tensile strength of the material.\nDie and punch shapes affect the force during the punching process. The punch force increases during the process as the entire thickness of the material is sheared at once. A beveled punch helps in the shearing of thicker materials by reducing the force at the beginning of the stroke. However, beveling a punch will distort the shape because of lateral forces that develop. Compound dies allow multiple shaping to occur. Using compound dies will generally slow down the process and are typically more expensive than other dies. Progressive dies may be used in high production operations. Different punching operations and dies may be used at different stages of the operation on the same machine.\nRelated processes.\nOther processes such as stamping, blanking, perforating, parting, drawing, notching, lancing and bending operations are all related to punching.\nPlastics.\nPunching in plastics fabrication usually refers to the removal of scrap plastic from the desired article. For example, in extrusion blow molding it is common to use punching dies to remove tails, molding flash (scrap plastic) and handle slugs from bottles or other molded containers.\nIn shuttle machinery, the containers are usually trimmed in the machines, and finished containers leave the blow molding machine. Other blow molding equipment, such as rotary wheel machinery, requires the use of downstream trimming. Types of downstream trimming equipment include detabbers for tail removal, rotary or reciprocating punch trimmers, and spin trimmers.", "Engineering,_Manufacturing": 1.0000056028, "qwen": "Yes"}
{"id": "11037019", "revid": "1131752336", "url": "https://en.wikipedia.org/wiki?curid=11037019", "title": "Chassis cab", "text": "A chassis cab, also called a cab chassis or half truck, is a type of vehicle construction, often found in medium duty truck commercial vehicles.\nInstead of supplying the customer with a factory pre-assembled flatbed, cargo container, or other equipment, the customer is given the vehicle with just chassis rails and a cab. This allows the customer to add any desired aftermarket equipment, such as fire apparatus, ambulance, or a recreational vehicle conversion package, which can be customized for the specific needs of the customer.\nCutaway van chassis are similar vehicles, but have specific components at the rear whereas chassis cabs usually do not have additional components.\nVehicles of this type are produced by Ford, Chevrolet/GMC, and Ram Trucks.", "Engineering,_Manufacturing": 0.999099493, "qwen": "Yes"}
{"id": "11040097", "revid": "38426523", "url": "https://en.wikipedia.org/wiki?curid=11040097", "title": "Calo tester", "text": "The Calo tester, also known as a ball craterer or coating thickness tester, is a simple and inexpensive piece of equipment used to measure the thickness of coatings. Coatings with thicknesses typically between 0.1 to 50 micrometres, such as Physical Vapor Deposition (PVD) coatings or Chemical Vapor Deposition (CVD) coatings, are used in many industries to improve the surface properties of tools and components. \nThe Calo tester is also used to measure the amount of coating wear after a wear test carried out using a Pin-on-Disc Tester.\nThe Calo tester consists of a holder for the surface to be tested and a steel sphere of known diameter that is rotated against the surface by a rotating shaft connected to a motor whilst diamond paste is applied to the contact area. The sphere is rotated for a short period of time (less than 20 seconds for a 0.1 to 5 micrometre thickness) but due to the abrasive nature of the diamond paste this is sufficient time to wear a crater through thin coatings.\nCalculating coating thickness using the Calo tester.\nAn optical microscope is used to take two measurements across the crater after the Calo test and the coating thickness is calculated using a simple geometrical equation. \nformula_1\nWhere\nt = coating thickness,\nd = diameter of the sphere \nx = difference between the radius of the crater and radius of the part of the crater at the bottom of the coating\nx+y = diameter of the crater", "Engineering,_Manufacturing": 0.9997080564, "qwen": "Yes"}
{"id": "4736445", "revid": "46016783", "url": "https://en.wikipedia.org/wiki?curid=4736445", "title": "Matsuura Machinery", "text": " is a machine tool manufacturing company based in Fukui, Fukui Prefecture, Japan, in operation since August 1935.\nMatsuura Machinery began as a manufacturer and distributor of lathes in 1935. Production of milling machines began in 1957, and the company went public in 1960. Production of automatic-controlled milling machines began in 1961 and numerically controlled milling machines from 1964. Production of automatically controlled drilling machines began in 1972, and vertical machining centers from 1974.\nThe company began exporting to the United States from 1975. In 1981, Matsuura Machinery began production of high-speed machining centers and twin-spindle vertical machining centers, and horizontal machining centers from 1983. The total number of machining centers shipped surpassed 10,000 units in 1993 and 20,000 in 2015.\nThe company's machining centers are used in a variety of industries, among them aerospace equipment manufacturers. Machine tools manufactured by Matsuura were used by NASA on the Space Shuttle Discovery's fuel tanks in 1998, making them four tons lighter than before.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "4742498", "revid": "1574590", "url": "https://en.wikipedia.org/wiki?curid=4742498", "title": "Downstream (manufacturing)", "text": "Downstream in manufacturing refers to processes that occur later on in a production sequence or production line.\nViewing a company \"from order to cash\" might have high-level processes such as Marketing, Sales, Order Entry, Manufacturing, Packaging, Shipping, Invoicing. Each of these could be deconstructed into many sub-processes and supporting processes.\nThe Manufacturing process consists of such sub-processes as Design, Tooling, Inventory Management, Receiving, Assembly, and others. The products being manufactured are created in a sequence of processes. Any process occurring after another is considered to be downstream.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "4749165", "revid": "7098284", "url": "https://en.wikipedia.org/wiki?curid=4749165", "title": "1997–98 UEFA Cup", "text": "The 1997–98 UEFA Cup was won by Internazionale in an all-Italian final against Lazio. It was their third title in eight years in the competition.\nIt was the first instance of the UEFA Cup final being a one-game contest at a neutral stadium, having previously being decided over two legs with each team having one home game.\nFor first time, one nation (France) was represented by seven teams: Strasbourg, Auxerre, Bastia, Nantes, Lyon, Bordeaux and Metz.\nFormat.\nAccording to 1996 UEFA ranking, Spain took a slot to Germany (but this one took the place of the holders), the Netherlands took a place from Russia, while Ukraine, Czech Republic, and Hungary took a slot from Israel, FR Yugoslavia and Poland (but this one took the place of troubled Albania).\nThe access list was finally decreased to 102 clubs, because only the 16 best national champions excluded from the Champions League group stage entered in the UEFA Cup.\nTeams.\nThe labels in the parentheses show how each team qualified for the place of its starting round:\nNotes\nFirst qualifying round.\nSecond leg.\n\"2–2 on aggregate; Dinamo Minsk won on away goals.\"\n\"Hapoel Petah Tikva won 3–1 on aggregate.\"\n\"Dnipro Dnipropetrovsk won 8–1 on aggregate.\"\n\"Boby Brno won 7–4 on aggregate.\"\n\"Apollon Limassol won 4–1 on aggregate.\"\n\"Celtic won 8-0 on aggregate.\"\n\"Neuchâtel Xamax won 10–1 on aggregate.\"\n\"Hajduk Split won 6–1 on aggregate.\"\n\"Grasshoppers won 10–1 on aggregate.\"\n\"2–2 on aggregate; Viking won 5–4 on penalties.\"\n\"KR Reykjavík won 4–1 on aggregate.\"\n\" Ferencváros won 6–0 on aggregate.\"\n\"FK Jablonec 97 won 8–0 on aggregate.\"\n\"Spartak Trnava won 4–1 on aggregate.\"\n\"Odra Wodzisław won 4–2 on aggregate.\"\n\"Vorskla Poltava won 5–2 on aggregate.\"\n\"4–4 on aggregate; Brann won on away goals.\"\n\"Dundee United won 17-0 on aggregate.\"\n\"4–4 on aggregate; Gorica won on away goals.\"\n\"Újpest won 9–2 on aggregate.\"\nSecond qualifying round.\nSecond leg.\n\"Hajduk Split won 5–2 on aggregate.\"\n\"Anderlecht won 4–0 on aggregate.\"\n\"Neuchâtel Xamax won 4–2 on aggregate.\"\n\"Rotor Volgograd won 6–3 on aggregate.\"\n\"Trabzonspor won 2–1 on aggregate.\"\n\"Rapid Wien won 6–3 on aggregate.\"\n\"Celtic won 7–5 on aggregate.\"\n\"1–1 on aggregate; Ferencváros won 4–3 on penalties.\"\n\"Hapoel Petah Tikva won 1–0 on aggregate.\"\n\"Grasshoppers won 3–2 on aggregate.\"\n\"Club Brugge won 8–3 on aggregate.\"\n\"PAOK won 6–3 on aggregate.\"\n\"OFI Crete won 3–1 on aggregate.\"\n\"1–1 on aggregate; Örebro won on away goals.\"\n\"Excelsior Mouscron won 3–0 on aggregate.\"\n\"Lillestrøm won 3–0 on aggregate.\"\n\"AGF Aarhus won 3–2 on aggregate.\"\n\"Alania Vladikavkaz won 6–2 on aggregate.\"\nFirst round.\nSecond leg.\n\"Auxerre won 2–1 on aggregate.\"\n\"Anderlecht won 7–6 on aggregate.\"\n\"PAOK won 2–1 on aggregate.\"\n\"Udinese won 3–1 on aggregate.\"\n\"Ajax won 10–2 on aggregate.\"\n\"Lyon won 7–3 on aggregate.\"\n\"Dinamo Tbilisi won 2–1 on aggregate.\"\n\"Real Valladolid won 2–1 on aggregate.\"\n\"Lazio won 6–1 on aggregate.\"\n\"Strasbourg won 4–2 on aggregate.\"\n\"MTK Hungária won 4–1 on aggregate.\"\n\"Schalke won 5–2 on aggregate.\"\n\"Bastia won 1–0 on aggregate.\"\n\"Spartak Moscow won 6–1 on aggregate.\"\n\"The original 2nd leg game finished 2–2 (scorers: Shirko, Alenichev – Lota 2x) on 30 September (Report), but had to be replayed because the goal posts were 8 cm short of the prescribed height.\"\n\"OFI Crete won 4–2 on aggregate.\"\n\"Athletic Bilbao won 4–1 on aggregate.\"\n\"Aston Villa won 1–0 on aggregate.\"\n\"Steaua București won 2–1 on aggregate.\"\n\"Rotor Volgograd won 6–1 on aggregate.\"\n\"1860 Munich won 7–1 on aggregate.\"\n\"Bochum won 6–5 on aggregate.\"\n\"Croatia Zagreb won 9–4 on aggregate.\"\n\"Braga won 3–2 on aggregate.\"\n\"Rapid Wien won 2–1 on aggregate.\"\n\"Internazionale won 4–0 on aggregate.\"\n\"2–2 on aggregate; Liverpool won on away goals.\"\n\"Metz won 6–1 on aggregate.\"\n\"2–2 on aggregate; Twente won on away goals.\"\n\"Club Brugge won 4–2 on aggregate.\"\n\"Atlético Madrid won 4–1 on aggregate.\"\n\"AGF Aarhus won 3–2 on aggregate.\"\n\"Karlsruhe won 3–2 on aggregate.\"\nSecond round.\nSecond leg.\n\"Strasbourg won 3–2 on aggregate.\"\n\"Internazionale won 4–3 on aggregate.\"\n\"Braga won 5–0 on aggregate.\"\n\"Schalke 04 won 3–1 on aggregate.\"\n\"2–2 on aggregate; Ajax won on away goals.\"\n\"Bochum won 4–2 on aggregate.\"\n\"Karlsruhe won 3–1 on aggregate.\"\n\"Spartak Moscow won 4–1 on aggregate.\"\n\"Croatia Zagreb won 2–1 on aggregate.\"\n\"Atlético Madrid won 9–6 on aggregate.\"\n\"3–3 on aggregate; Steaua București won on away goals.\"\n\"Aston Villa won 2–1 on aggregate.\"\n\"Rapid Wien won 4–2 on aggregate.\"\n\"Lazio won 3–0 on aggregate.\"\n\"1–1 on aggregate; Twente won on away goals.\"\n\"Auxerre won 5–4 on aggregate.\"\nThird round.\nThe draw for the third round was held on 7 November 1997.\nSecond leg.\n\"Internazionale won 3–2 on aggregate.\"\n\"Schalke 04 won 2–0 on aggregate.\"\n\"Ajax won 6–4 on aggregate.\"\n\"Spartak Moscow won 1–0 on aggregate.\"\n\"Atlético Madrid won 2–1 on aggregate.\"\n\"Aston Villa won 3–2 on aggregate.\"\n\"Lazio won 3–0 on aggregate.\"\n\"Auxerre won 3–0 on aggregate.\"\nQuarter-finals.\nSecond leg.\n\"Internazionale won 2–1 on aggregate.\"\n\"Spartak Moscow won 4–1 on aggregate.\"\n\"2–2 on aggregate; Atlético Madrid won on away goals.\"\n\"Lazio won 3–2 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Internazionale won 4–2 on aggregate.\"\n\"Lazio won 1–0 on aggregate.\"", "Engineering,_Manufacturing": 0.9980165362, "qwen": "Yes"}
{"id": "31660017", "revid": "35246606", "url": "https://en.wikipedia.org/wiki?curid=31660017", "title": "Multi-pack", "text": "A multi-pack also known as multipack is packaging that combines or holds multiple items or smaller packages.\nFunctions.\nMulti-packs can be used to:\nMethods.\nA wide variety of materials and procedures are available to combine items or packages into a multi-pack. This can include shrink film, pressure sensitive tape, paper overwrap, adhesives, paperboard carriers, plastic clips, etc.\nBeverages.\nBeverage cans and bottles are sold in multi-packs such as six packs, twelve packs, and cases of 24. These can be paperboard baskets, paperboard overwraps and cartons, corrugated fiberboard boxes, HDPE plastic handles, six pack rings, and shrink packs.\nOther uses.\nA wide variety of items and packages are combined into multi-packs for sale.", "Engineering,_Manufacturing": 1.000000596, "qwen": "Yes"}
{"id": "31689204", "revid": "64979", "url": "https://en.wikipedia.org/wiki?curid=31689204", "title": "Low pressure molding", "text": "Low pressure molding (LPM) with polyamide and polyolefin (hot-melt) materials is a process typically used to encapsulate and environmentally protect electronic components (such as circuit boards). The purpose is to protect electronics against moisture, dust dirt and vibration. Low pressure molding is also used for sealing connectors and molding grommets and strain reliefs.\nProcess.\nKey to this process are the raw materials and specialized molding equipment. Dimer acid based polyamide materials, better known as hot-melts, are used as molding compounds. They are thermoplastics i.e. the material, when heated, becomes less viscous and is able to be reshaped, then hardens to keep the desired form upon cooling down. These polyamide materials differ from other thermoplastics in two main areas:\nThe mainly used amorphous thermoplastic polyamides combine a favourable viscosity spectrum with a wide application temperature range from . The material is heated until liquid (typically at ) and then injected at very low pressure, typically into a relative cold mold-set. The low viscosity polyamide material flows gently into the mold-set cavity and around the electronics to be encapsulated. It also starts cooling down as soon as it touches the mold-set cavity and the electronics. A mold-set cavity is typically filled in a few seconds but a typical full molding cycle is 20 to 45 seconds. As the polyamide material starts to cool down it also starts to shrink. Continuous injection pressure is therefore applied to the cavity, even after its initial fill. This is done in order to compensate for the shrinkage that naturally occurs when the polyamide material goes from liquid to solid (i.e. hot to cold). The polyamide temperature is not too hot for the electronics and does not re-melt or re-flow the solder. This is simply because the relative cold mold-set will absorb the brunt of the heat, thereby reducing the temperature that a circuit board may see. Millions of circuit boards are successfully over-molded without causing any harm in the process. A low injection pressure does not stress a fragile solder joint.\nUse.\nThe low pressure molding process was initially used in Europe in the 1970s to seal connectors and create strain reliefs for wires. The first commercial use of the low pressure molding process was in the automotive industry. The driving force was to replace toxic and cumbersome potting processes, faster cycle times, lighter parts and environmentally safe components and for some applications to replace heat shrink tubings.\nSince then low pressure molding has spread out to other areas such as industrial products, medical, consumer products, military, wire harness and any unique product that needs to be sealed and protected against the environment, like Automotive sensors in-cabin and even under hood, USB thumb drives, RFID tags, moisture sensors, motor control boards, consumer products. In essence the process acts as a middle ground between plastic injection molding which subjects components to high pressure and temperatures that can often damage them and potting with resin a process that involves waste and lengthy curing times.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "48717538", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=48717538", "title": "E-four", "text": "E-Four (short for Electrical 4WD System), eFour, AWD-i, or AWD-e was developed by Toyota. Front wheels are powered directly by the hybrid powertrain, rear wheels are powered by a dedicated electric motor with its own power control unit, reduction gear and differential. Amount of torque transferred to the rear wheels is automatically adjusted by the vehicle's electronic control unit according to driving conditions. E-Four also adds additional regenerative braking. In North America, Toyota uses the term \"AWD-i\" (All-Wheel Drive with Intelligence). There is no drive shaft between the front combustion engine and rear wheels. The rear wheels only receive power and torque from the rear electric motor(s).\nE-Four was first implemented in the 2001 Toyota Estima Hybrid and is used in several Toyota and Lexus cars, e.g. 2016 Toyota RAV4, Lexus NX 300h, Lexus RX 450h, and Toyota Prius AWD-e, and in the future may be used in the standard fifth generation Toyota Prius. In Japan, the all-wheel-drive Prius has been available since 2015 and bumps the price by about $1700. The compact HV4WD E-Four used for the Prius adds little weight and doesn't reduce the fuel economy or interior storage. A few weeks before the November 2018 Los Angeles Auto Show, Toyota issued a press release with text and images featuring the car in snowy conditions, suggesting the E-Four package would likely debut in the 2019 U.S. model at the show.", "Engineering,_Manufacturing": 0.9967634082, "qwen": "Yes"}
{"id": "4553159", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=4553159", "title": "Proportional share scheduling", "text": "Proportional Share Scheduling is a type of scheduling that preallocates certain amount of CPU time to each of the processes. In a proportional share algorithm every job has a weight, and jobs receive a share of the available resources proportional to the weight of every job.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "2549545", "revid": "1064220649", "url": "https://en.wikipedia.org/wiki?curid=2549545", "title": "Lathe center", "text": "A lathe center, often shortened to center, is a tool that has been ground to a point to accurately position a workpiece on an axis. They usually have an included angle of 60°, but in heavy machining situations an angle of 75° is used.\nThe primary use of a center is to ensure concentric work is produced; this allows the workpiece to be transferred between machining (or inspection) operations without any loss of accuracy. A part may be \"turned\" in a lathe, sent off for hardening and tempering and then ground \"between centers\" in a cylindrical grinder. The preservation of concentricity between the turning and grinding operations is crucial for quality work.\nWhen turning between centres, a steady can be used to support longer workpieces where the cutting forces would deflect the work excessively, reducing the finish and accuracy of the workpiece, or creating a hazardous situation.\nA center lathe has applications anywhere that a \"centered\" workpiece may be used; this is not limited to lathe usage but may include setups in dividing heads, cylindrical grinders, tool and cutter grinders or other related equipment. The term \"between centers\" refers to any machining operation where the job needs to be performed using centers.\nA center is inserted into a matching hole drilled by a center drill. The hole is conical near the surface and cylindrical as it gets deeper.\nDead center (and live center).\nA dead center (one that does not turn freely, i.e., \"dead\") may be used to support the workpiece at either the fixed or rotating end of the machine. When used in the fixed position, a dead center produces friction between the workpiece and center, due to the rotation of the workpiece. Lubrication is therefore required between the center and workpiece to prevent friction welding from occurring. Additionally the tip of the center may have an insert of cemented carbide which will reduce the friction slightly and allow for faster speeds. Dead centers are typically fully hardened to prevent damage to the important mating surfaces of the taper and to preserve the 60° angle of the nose. As tungsten carbide is much harder than steel, a carbide-tipped center has greater wear resistance than a steel center.\nWhen turning between centres, a 'dead centre' is used in the headstock as well as the tailstock. As the one in the headstock revolves with the work, this centre is known as a live centre.\nSoft center.\nSoft centers are a special version of the dead center in which the nose is deliberately left soft (unhardened) so that it may be readily machined to the correct angle prior to usage. This operation is performed on the headstock center to ensure that the center's axis is aligned with the spindle's axis.\nRunning or revolving center.\nA revolving center, also known as a rotating center or running center in some countries, is constructed so that the 60° center runs in its own bearings and is used at the non-driven or tailstock end of a machine. It allows higher turning speeds without the need for separate lubrication, and also greater clamping pressures. CNC lathes use this type of center almost exclusively and they may be used for general machining operations as well. Spring-loaded centers are designed to compensate for center variations, without damage to the work piece or center tip. This assures the operator of uniform constant tension while machining. Some live centers also have interchangeable shafts. This is valuable when situations require a design other than a 60° male tip. A live center, which may be hard or soft, is a plain center placed in the revolving mandrel; it moves and is therefore live.\nPipe center.\nA pipe center, also known as a bull nose center is a type of live center which has a large diameter conical nose rather than a sharp point. This allows the center to be used in the bore of a pipe or other workpiece with a large interior diameter. While a pipe center ensures the workpiece remains concentric, its main advantage is that it supports the workpiece securely, and can be used for parts whose larger inner diameter prevents the use of a normal pointed center. Thin-walled material such as pipes easily collapses if excessive force is used at the chuck end.\nCup center.\nThere are two types of cup centers. The woodworking variety is a variation of the traditional live center. This type of cup center has a central point like a normal live center and also has a ring surrounding it. The ring supports the softer material around the center point and prevents the wood from splitting under pressure from the central point. A different variety of cup center is used for metalworking. The metalworking variety of cup center has a tapered hole rather than a conical point. It supports the part by making contact with the outside diameter of the end of the part, rather than using a center hole.\nDrive center.\nA drive center, also known as a grip center, is used in the driving end of a machine (headstock). It is often used in woodworking or where softer materials are machined.\nIt consists of a dead center surrounded by hardened teeth, which bite into a softer workpiece allowing the workpiece to be driven directly by the center. This allows the full diameter of the workpiece to be machined in a single operation, in contrast with the usual requirement where a carrier is attached to the workpiece at the driven end. The use of modified shell end mills in a drive center, instead of hardened pins, enables better gripping and prevents breakdown time due to pin stop.\nSpring center.\nA spring center is a metalworking lathe center for maintaining a cutting tool like a reamer or a tap, in axial alignment with a hole being worked on. It consists of a point backed by a spring to push the cutting tool into the workpiece.", "Engineering,_Manufacturing": 0.9999809265, "qwen": "Yes"}
{"id": "2551777", "revid": "41543365", "url": "https://en.wikipedia.org/wiki?curid=2551777", "title": "Metal lathe", "text": "In machining, a metal lathe or metalworking lathe is a large class of lathes designed for precisely machining relatively hard materials. They were originally designed to machine metals; however, with the advent of plastics and other materials, and with their inherent versatility, they are used in a wide range of applications, and a broad range of materials. In machining jargon, where the larger context is already understood, they are usually simply called \"lathes\", or else referred to by more-specific subtype names (\"toolroom lathe\", \"turret lathe\", etc.). These rigid machine tools remove material from a rotating workpiece via the (typically linear) movements of various cutting tools, such as tool bits and drill bits.\nConstruction.\nThe design of lathes can vary greatly depending on the intended application; however, basic features are common to most types. These machines consist of (at the least) a headstock, bed, carriage, and tailstock. Better machines are solidly constructed with broad bearing surfaces (\"slide-ways\") for stability, and manufactured with great precision. This helps ensure the components manufactured on the machines can meet the required tolerances and repeatability.\nHeadstock.\nThe headstock (H1) houses the main spindle (H4), speed change mechanism (H2, H3), and change gears (H10). The headstock is required to be made as robust as possible due to the cutting forces involved, which can distort a lightly built housing, and induce harmonic vibrations that will transfer through to the workpiece, reducing the quality of the finished workpiece.\nThe main spindle is generally hollow to allow long bars to extend through to the work area. This reduces preparation and waste of material. The spindle runs in precision bearings and is fitted with some means of attaching workholding devices such as chucks or faceplates. This end of the spindle usually also has an included taper, frequently a Morse taper, to allow the insertion of hollow tubular (Morse standard) tapers to reduce the size of the tapered hole, and permit use of centers. \nOn older machines ('50s) the spindle was directly driven by a flat belt pulley with lower speeds available by manipulating the bull gear. Later machines use a gear box driven by a dedicated electric motor. A fully 'geared head' allows the operator to select suitable speeds entirely through the gearbox.\nBeds.\nThe bed is a robust base that connects to the headstock and permits the carriage and tailstock to be moved parallel with the axis of the spindle. This is facilitated by hardened and ground bedways which restrain the carriage and tailstock in a set track. The carriage travels by means of a rack and pinion system. The leadscrew of accurate pitch, drives the carriage holding the cutting tool via a gearbox driven from the headstock.\nTypes of beds include inverted \"V\" beds, flat beds, and combination \"V\" and flat beds. \"V\" and combination beds are used for precision and light duty work, while flat beds are used for heavy duty work.\nWhen a lathe is installed, the first step is to \"level\" it, which refers to making sure the bed is not twisted or bowed. There is no need to make the machine exactly horizontal, but it must be entirely untwisted to achieve accurate cutting geometry. A precision level is a useful tool for identifying and removing any twist. It is advisable also to use such a level along the bed to detect bending, in the case of a lathe with more than four mounting points. In both instances the level is used as a comparator rather than an absolute reference.\nFeed and lead screws.\nThe feedscrew (H8) is a long driveshaft that allows a series of gears to drive the carriage mechanisms. These gears are located in the apron of the carriage. Both the feedscrew and leadscrew (H7) are driven by either the change gears (on the quadrant) or an intermediate gearbox known as a quick change gearbox (H6) or Norton gearbox. These intermediate gears allow the correct ratio and direction to be set for cutting threads or worm gears. Tumbler gears (operated by H5) are provided between the spindle and gear train along with a quadrant plate that enables a gear train of the correct ratio and direction to be introduced. This provides a constant relationship between the number of turns the spindle makes, to the number of turns the leadscrew makes. This ratio allows screwthreads to be cut on the workpiece without the aid of a die.\nSome lathes have only one leadscrew that serves all carriage-moving purposes. For screw cutting, a half nut is engaged to be driven by the leadscrew's thread; and for general power feed, a key engages with a keyway cut into the leadscrew to drive a pinion along a rack that is mounted along the lathe bed.\nThe leadscrew will be manufactured to either imperial or metric standards and will require a conversion ratio to be introduced to create thread forms from a different family. To accurately convert from one thread form to the other requires a 127-tooth gear, or on lathes not large enough to mount one, an approximation may be used. Multiples of 3 and 7 giving a ratio of 63:1 can be used to cut fairly loose threads. This conversion ratio is often built into the \"quick change gearboxes\".\nThe precise ratio required to convert a lathe with an Imperial (inch) leadscrew to metric (millimeter) threading is 100 / 127 = 0.7874... . The best approximation with the fewest total teeth is very often 37 / 47 = 0.7872... . This transposition gives a constant -0.020 percent error over all customary and model-maker's metric pitches (0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.60, 0.70, 0.75, 0.80, 1.00, 1.25, 1.50, 1.75, 2.00, 2.50, 3.00, 3.50, 4.00, 4.50, 5.00, 5.50 and 6.00 mm).\nCarriage.\nIn its simplest form the carriage holds the tool bit and moves it longitudinally (turning) or perpendicularly (facing) under the control of the operator. The operator moves the carriage manually via the \"handwheel\" (5a) or automatically by engaging the feed shaft with the carriage feed mechanism (5c). This provides some relief for the operator as the movement of the carriage becomes power assisted. The handwheels (2a, 3b, 5a) on the carriage and its related slides are usually calibrated, both for ease of use and to assist in making reproducible cuts. The carriage typically comprises a top casting, known as the saddle (4), and a side casting, known as the apron (5).\nCross-slide.\nThe cross-slide (3) rides on the carriage and has a feedscrew which travels at right angles to the main spindle axis. This permits \"facing\" operations to be performed, and the depth of cut to be adjusted. This feedscrew can be engaged, through a gear train, to the feed shaft (mentioned previously) to provide automated 'power feed' movement to the cross-slide. On most lathes, only one direction can be engaged at a time as an interlock mechanism will shut out the second gear train.\nCross-slide handwheels are usually marked in terms of the part's \"diameter\", so one graduation representing .001 inches of diameter corresponds to .0005 inches of cross-slide motion.\nCompound rest.\nThe compound rest (or top slide) (2) is usually where the tool post is mounted. It provides a smaller amount of movement (less than the cross-slide) along its axis via another feedscrew. The compound rest axis can be adjusted independently of the carriage or cross-slide. It is used for turning tapers, to control depth of cut when screwcutting or precision facing, or to obtain finer feeds (under manual control) than the feed shaft permits. Usually, the compound rest has a protractor marked in its base (2b), enabling the operator to adjust its axis to precise angles.\nThe slide rest (as the earliest forms of carriage were known) can be traced to the fifteenth century. In 1718 the tool-supporting slide rest with a set of gears was introduced by a Russian inventor Andrey Nartov and had limited usage in the Russian industry.\nThe first fully documented, all-metal slide rest lathe was invented by Jacques de Vaucanson around 1751. It was described in the \"Encyclopédie\" a long time before Maudslay invented and perfected his version. It is likely that Maudslay was not aware of Vaucanson's work, since his first versions of the slide rest had many errors that were not present in the Vaucanson lathe.\nIn the eighteenth century the slide rest was also used on French ornamental turning lathes.\nThe suite of gun boring mills at the Royal Arsenal, Woolwich, in the 1780s by the Verbruggan family also had slide rests. The story has long circulated that Henry Maudslay invented it, but he did not (and never claimed so). The legend that Maudslay invented the slide rest originated with James Nasmyth, who wrote ambiguously about it in his \"Remarks on the Introduction of the Slide Principle\", 1841; later writers misunderstood, and propagated the error. However, Maudslay did help to disseminate the idea widely. It is highly probable that he saw it when he was working at the Arsenal as a boy. In 1794, whilst he was working for Joseph Bramah, he made one, and when he had his own workshop used it extensively in the lathes he made and sold there. Coupled with the network of engineers he trained, this ensured the slide rest became widely known and copied by other lathe makers, and so diffused throughout British engineering workshops. A practical and versatile screw-cutting lathe incorporating the trio of leadscrew, change gears, and slide rest was Maudslay's most important achievement.\nToolpost.\nThe tool bit is mounted in the toolpost (1) which may be of the American \"lantern\" style, traditional four-sided square style, or a quick-change style such as the multi-fix arrangement pictured. The advantage of a quick change set-up is to allow an unlimited number of tools to be used (up to the number of holders available) rather than being limited to one tool with the lantern style, or to four tools with the four-sided type. Interchangeable tool holders allow all tools to be preset to a \"center\" height that does not change, even if the holder is removed from the machine.\nTailstock.\nThe tailstock is a tool (drill), and center mount, opposite the headstock. The spindle (T5) does not rotate but does travel longitudinally under the action of a leadscrew and handwheel (T1). The spindle includes a taper to hold drill bits, centers and other tooling. The tailstock can be positioned along the bed and clamped (T6) in position as dictated by the work piece. There is also provision to offset the tailstock (T4) from the spindles axis, this is useful for turning small tapers, and when re-aligning the tailstock to the axis of the bed.\nThe image shows a reduction gear box (T2) between the handwheel and spindle, where large drills may necessitate the extra leverage.\nThe tool bit is normally made of HSS, cobalt steel or carbide.\nSteady, follower and other rests.\nLong workpieces often need to be supported in the middle, as cutting tools can push (bend) the work piece away from where the centers can support them, because cutting metal produces tremendous forces that tend to vibrate or even bend the workpiece. This extra support can be provided by a steady rest (also called a steady, a fixed steady, a center rest, or sometimes, confusingly, a center). It stands stationary from a rigid mounting on the bed, and it supports the workpiece at the rest's center, typically with three contact points 120° apart. A follower rest (also called a follower or a travelling steady) is similar, but it is mounted to the carriage rather than the bed, which means that as the tool bit moves, the follower rest \"follows along\" (because they are both rigidly connected to the same moving carriage).\nFollower rests can provide support that directly counteracts the springing force of the tool bit, right at the region of the workpiece being cut at any moment. In this respect they are analogous to a box tool. Any rest transfers some workpiece geometry errors from base (bearing surface) to processing surface. It depends on the rest design. For minimum transfer rate correcting rests are used. Rest rollers typically cause some additional geometry errors on the processing surface.\nTypes of metal lathes.\nThere are many variants of lathes within the metalworking field. Some variations are not all that obvious, and others are more a niche area. For example, a centering lathe is a dual head machine where the work remains fixed and the heads move towards the workpiece and machine a center drill hole into each end. The resulting workpiece may then be used \"between centers\" in another operation.\nThe usage of the term metal lathe may also be considered somewhat outdated these days. Plastics and other composite materials are in wide use and, with appropriate modifications, the same principles and techniques may be applied to their machining as that used for metal.\nCenter lathe / engine lathe / bench lathe.\nThe terms center lathe, engine lathe, and bench lathe all refer to a basic type of lathe that may be considered the archetypical class of metalworking lathe most often used by the general machinist or machining hobbyist. The name \"bench lathe\" implies a version of this class small enough to be mounted on a workbench (but still full-featured, and larger than mini-lathes or micro-lathes). The construction of a center lathe is detailed above, but depending on the year of manufacture, size, price range or desired features, even these lathes can vary widely between models.\n\"Engine lathe\" is the name applied to a traditional late-19th-century or 20th-century lathe with automatic feed to the cutting tool, as opposed to early lathes which were used with hand-held tools, or lathes with manual feed only. The usage of \"engine\" here is in the mechanical-device sense, not the prime-mover sense, as in the steam engines which were the standard industrial power source for many years. The works would have one large steam engine which would provide power to all the machines via a line shaft system of belts. Therefore, early engine lathes were generally 'cone heads', in that the spindle usually had attached to it a multi-step pulley called a \"cone pulley\" designed to accept a flat belt. Different spindle speeds could be obtained by moving the flat belt to different steps on the cone pulley. Cone-head lathes usually had a countershaft (layshaft) on the back side of the cone which could be engaged to provide a lower set of speeds than was obtainable by direct belt drive. These gears were called \"back gears\". Larger lathes sometimes had two-speed back gears which could be shifted to provide a still lower set of speeds.\nWhen electric motors started to become common in the early 20th century, many cone-head lathes were converted to electric power. At the same time the state of the art in gear and bearing practice was advancing to the point that manufacturers began to make fully geared headstocks, using gearboxes analogous to automobile transmissions to obtain various spindle speeds and feed rates while transmitting the higher amounts of power needed to take full advantage of high-speed steel tools. Cutting tools evolved once again, with the introduction of man-made carbides, and became widely introduced to general industry in the 1970s. Early carbides were attached to toolholders by brazing them into a machined 'nest' in the tool holders. Later designs allowed tips to be replaceable and multi faceted, allowing them to be reused. Carbides tolerate much higher machining speeds without wearing. This has led to machining times shortening, and therefore production growing. The demand for faster and more powerful lathes controlled the direction of lathe development.\nThe availability of inexpensive electronics has again changed the way speed control may be applied by allowing continuously variable motor speed from the maximum down to almost zero RPM. This had been tried in the late 19th century but was not found satisfactory at the time. Subsequent improvements in electric circuitry have made it viable again.\nToolroom lathe.\nA toolroom lathe is a lathe optimized for toolroom work. It is essentially just a top-of-the-line center lathe, with all of the best optional features that may be omitted from less expensive models, such as a collet closer, taper attachment, and others. The bed of a toolroom lathe is generally wider than that of a standard center lathe. There has also been an implication over the years of selective assembly and extra fitting, with every care taken in the building of a toolroom model to make it the smoothest-running, most-accurate version of the machine that can be built. However, within one brand, the quality difference between a regular model and its corresponding toolroom model depends on the builder and in some cases has been partly marketing psychology. For name-brand machine tool builders who made only high-quality tools, there wasn't necessarily any lack of quality in the base-model product for the \"luxury model\" to improve upon. In other cases, especially when comparing different brands, the quality differential between (1) an entry-level center lathe built to compete on price, and (2) a toolroom lathe meant to compete only on quality and not on price, can be objectively demonstrated by measuring TIR, vibration, etc. In any case, because of their fully ticked-off option list and (real or implied) higher quality, toolroom lathes are more expensive than entry-level center lathes.\nTurret lathe and capstan lathe.\nTurret lathes and capstan lathes are members of a class of lathes that are used for repetitive production of duplicate parts (which by the nature of their cutting process are usually interchangeable). It evolved from earlier lathes with the addition of the \"turret\", which is an indexable tool holder that allows multiple cutting operations to be performed, each with a different cutting tool, in easy, rapid succession, with no need for the operator to perform setup tasks in between (such as installing or uninstalling tools) nor to control the toolpath. (The latter is due to the toolpath being controlled by the machine, either in jig-like fashion via the mechanical limits placed on it by the turret's slide and stops, or via computer-directed servo mechanisms on CNC lathes.)\nThere is a tremendous variety of turret lathe and capstan lathe designs, reflecting the variety of work that they do.\nGang-tool lathe.\nA gang-tool lathe is one that has a row of tools set up on its cross-slide, which is long and flat and is similar to a milling machine table. The idea is essentially the same as with turret lathes: to set up multiple tools and then easily index between them for each part-cutting cycle. Instead of being rotary like a turret, the indexable tool group is linear.\nMultispindle lathe.\nMultispindle lathes have more than one spindle and automated control (whether via cams or CNC). They are production machines specializing in high-volume production. The smaller types are usually called screw machines, while the larger variants are usually called automatic chucking machines, automatic chuckers, or simply chuckers. Screw machines usually work from bar stock, while chuckers automatically chuck up individual blanks from a magazine. Typical minimum profitable production lot size on a screw machine is in the thousands of parts due to the large setup time. Once set up, a screw machine can rapidly and efficiently produce thousands of parts on a continuous basis with high accuracy, low cycle time, and very little human intervention. (The latter two points drive down the unit cost per interchangeable part much lower than could be achieved without these machines.)\nCNC lathe / CNC turning center.\nComputer numerical controlled (CNC) lathes are rapidly replacing the older production lathes (multispindle, etc.) due to their ease of setting, operation, repeatability and accuracy. A CNC Turning Lathe is a Computer Controlled piece of machinery. It allows basic machining operations such as turning and drilling to be carried out as on a conventional lathe. They are designed to use modern carbide tooling and fully use modern processes. The part may be designed and the tool paths programmed by the CAD/CAM process or manually by the programmer, and the resulting file uploaded to the machine, and once set and trialled the machine will continue to turn out parts under the occasional supervision of an operator.\nThe machine is controlled electronically via a computer menu style interface, the program may be modified and displayed at the machine, along with a simulated view of the process. The setter/operator needs a high level of skill to perform the process. However, the knowledge base is broader compared to the older production machines where intimate knowledge of each machine was considered essential. These machines are often set and operated by the same person, where the operator will supervise a small number of machines (cell).\nThe design of a CNC lathe varies with different manufacturers, but they all have some common elements. The turret holds the tool holders and indexes them as needed, the spindle holds the workpiece and there are slides that let the turret move in multiple axes simultaneously. The machines are often totally enclosed, due in large part to occupational health and safety (OH&S) issues.\nWith rapid growth in this industry, different CNC lathe manufacturers use different user interfaces which sometimes makes it difficult for operators as they have to be acquainted with them. With the advent of cheap computers, free operating systems such as Linux, and open source CNC software, the entry price of CNC machines has plummeted.\nCNC Horizontal Milling.\nCNC horizontal machining is performed using horizontally-configured lathes, machining centers, boring machines, or boring mills. The equipment used typically consists of rotating cylindrical cutters moving up and down along five axes. These machines are capable of producing a variety of shapes, slots, and details on a three-dimensional part.\nCNC Vertical Milling.\nVertically-oriented CNC machines utilize cylindrical cutters on a vertical spindle axis to create plunge cuts and drilled holes, as well as custom shapes, slots, and details on three-dimensional parts. Equipment used in this type of milling includes vertical lathes, vertical machining centers, and 5-axis machines.\nSwiss-style lathe / Swiss turning center.\nA Swiss-style lathe is a specific design of lathe providing extreme accuracy (sometimes holding tolerances as small as a few tenths of a thousandth of an inch—a few micrometers). A Swiss-style lathe holds the workpiece with both a collet and a guide bushing. The collet sits behind the guide bushing, and the tools sit in front of the guide bushing, holding stationary on the Z axis. To cut lengthwise along the part, the tools will move in and the material itself will move back and forth along the Z axis. This allows all the work to be done on the material near the guide bushing where it is more rigid, making them ideal for working on slender workpieces as the part is held firmly with little chance of deflection or vibration occurring. This style of lathe is commonly used under CNC control.\nMost CNC Swiss-style lathes today use one or two main spindles plus one or two back spindles (secondary spindles). The main spindle is used with the guide bushing for the main machining operations. The secondary spindle is located behind the part, aligned on the Z axis. In simple operation it picks up the part as it is cut off, and accepts it for second operations, then ejects it into a bin, eliminating the need to have an operator manually change each part, as is often the case with standard CNC turning centers. This makes them very efficient, as these machines are capable of fast cycle times, producing simple parts in one cycle (i.e., no need for a second machine to finish the part with second operations), in as little as 10–15 seconds. This makes them ideal for large production runs of small-diameter parts.\nSwiss-style Lathes and Live Tooling.\nAs many Swiss lathes incorporate a secondary spindle, or 'sub-spindle', they also incorporate 'live tooling'. Live tools are rotary cutting tools that are powered by a small motor independently of the spindle motor. Live tools increase the intricacy of components that can be manufactured by the Swiss lathe. For instance, automatically producing a part with a hole drilled perpendicular to the main axis (the axis of rotation of the spindles) is very economical with live tooling, and similarly uneconomical if done as a secondary operation after machining by the Swiss lathe is complete. A 'secondary operation' is a machining operation requiring a partially completed part to be secured in a second machine to complete the manufacturing process. Generally, advanced CAD/CAM software uses live tools in addition to the main spindles so that most parts that can be drawn by a CAD system can actually be manufactured by the machines that the CAD/CAM software support.\nCombination lathe / 3-in-1 machine.\nA combination lathe, often known as a 3-in-1 machine, introduces drilling or milling operations into the design of the lathe. These machines have a milling column rising up above the lathe bed, and they utilize the carriage and topslide as the X and Y axes for the milling column. The \"3-in-1\" name comes from the idea of having a lathe, milling machine, and drill press all in one affordable machine tool. These are exclusive to the hobbyist and MRO markets, as they inevitably involve compromises in size, features, rigidity, and precision in order to remain affordable. Nevertheless, they meet the demand of their niche quite well, and are capable of high accuracy given enough time and skill. They may be found in smaller, non-machine-oriented businesses where the occasional small part must be machined, especially where the exacting tolerances of expensive toolroom machines, besides being unaffordable, would be overkill for the application from an engineering perspective.\nMini-lathe and micro-lathe.\nMini-lathes and micro-lathes are miniature versions of a general-purpose center lathe (engine lathe). They typically only handle work of diameter (in other words, radius). They are small and affordable lathes for the home workshop or MRO shop. The same advantages and disadvantages apply to these machines as explained earlier regarding 3-in-1 machines.\nAs found elsewhere in English-language orthography, there is variation in the styling of the prefixes in these machines' names. They are alternately styled as mini lathe, minilathe, and mini-lathe and as micro lathe, microlathe, and micro-lathe.\nBrake lathe.\nA lathe specialized for the task of resurfacing brake drums and discs in automotive or truck garages.\nWheel lathe.\nWheel lathes are machines used to manufacture and resurface the wheels of railway rolling stock. When wheels become worn or compromised from excessive use, this tool can be used to re-cut and recondition the wheel. There are a number of different wheel lathes available including underfloor variations for resurfacing wheels that are still attached to the rail car, portable types that are easily transported for emergency wheel repairs, and CNC versions which utilize computer-based operating systems to complete the wheel repair.\nPit lathe.\nA lathe for large diameter, though short work, built over a recess in the floor to admit the lower part of the workpiece thus allowing the toolrest to stand at the turner's waist height. An example is on display at the London Science Museum, Kensington.\nVertical lathe.\nFor even larger diameter and heavier work, such as pressure vessels or marine engines, the lathe is rotated so it takes the form of a turntable on which parts are placed. This orientation is less convenient for the operator, but makes it easier to support large parts. In the largest, the turntable is installed flush with the floor, with the headstock recessed below, to facilitate loading and unloading workpieces.\nBecause operator access is less of an issue for them, CNC vertical turning machines are more popular than manual vertical lathes.\nOil country lathe.\nSpecialised lathes for machining long workpieces such as segments of drill strings. Oil country lathes are equipped with large-bore hollow spindles, a second chuck on the opposite side of the headstock, and frequently outboard steadies for supporting long workpieces.\nFeed mechanisms.\nVarious feed mechanisms exist to feed material into a lathe at a defined rate. The aim of these mechanisms is to automate part of the production process with the end goal of improving productivity.\nBar feeder.\nA bar feeder feeds a single piece of bar stock into the cutting machine. As each part is machined, the cutting tool creates a final cut to separate the part from the bar stock, and the feeder continues to feed the bar for the next part, allowing for continual operation of the machine. There are two types of bar feeds used in lathe machining: Hydrodynamic bar feeds, which rest the bar stock in a series of channels whilst clamping down on the top and bottom of the bar, and hydrostatic bar feeds, which hold the bar stock in a feed tube using pressurized oil.\nBar loader.\nA bar loader is a variation on the bar feeder concept in that multiple pieces of bar stock may be fed into a hopper, and the loader feeds each piece as necessary.", "Engineering,_Manufacturing": 0.9999862909, "qwen": "Yes"}
{"id": "2554894", "revid": "143538", "url": "https://en.wikipedia.org/wiki?curid=2554894", "title": "Service level", "text": "Service level measures the performance of a system. Certain goals are defined and the service level gives the percentage to which those goals should be achieved. Fill rate is different from service level.\nExamples of service level:\n(Explanation) if one component part of an order is not filled the Service Level for that order is Zero, If all the component parts of an order are delivered except one is filled at 51%, the service level for that order is 51% (This system is often used in supply chain delivery to manufacturing), This is a very different from a simple order fill measurement which does not consider line items on the order.\nService level.\nService level is used in supply-chain management and in inventory management to measure the performance of inventory replenishment policies. Under consideration, from the optimal solution of such a model also the optimal size of back orders can be derived.\nUnfortunately, this optimization approach requires that the planner knows the optimal value of the back order costs. As these costs are difficult to quantify in practice, the logistical performance of an inventory node in a supply network is measured with the help of technical performance measures. The target values of these measures are set by the decision maker.\nSeveral definitions of service levels are used in the literature as well as in practice. These may differ not only with respect to their scope and to the number of considered products but also with respect to the time interval they are related to. These performance measures are the \"key performance indicators\" (KPI) of an inventory node which must be regularly monitored. If the controlling of the performance of an inventory node is neglected, the decision maker will not be able to optimize the processes within a supply chain.\nα service level (type 1).\nThe α service level is an event-oriented performance criterion. It measures the probability that\n\"all\" customer orders arriving within a given time interval will be completely delivered from stock on hand, i.e. without delay.\nTwo versions are discussed in the literature differing with respect to the time interval within which the customers arrive.\nWith reference to a \"demand period\", α denotes the probability that an arbitrarily arriving customer order will be completely served from stock on hand, i.e. without an inventory-related waiting time (period formula_1 service level):\nformula_2.\nIn order to determine the safety stock that guarantees a target formula_1 service\nlevel, the stationary probability distribution of the inventory on hand must be known. This version of α is also called \"ready rate\".\nIf an \"order cycle\" is considered as the standard period of reference, then α denotes the probability of no stockout within an order cycle which is equal to the proportion of all order cycles with no stockouts (cycle formula_4 service level):\nformula_5\nThis second definition, which is often used in operations management textbooks, is based on the idea of not running out of stock during the time between re-ordering and order arrival (the leadtime). That is, the probability of demand during that leadtime being less than or equal to the amount of stock you had left when you ordered. It assumes your reorder point is positive, that orders are in unit increments and inventory is monitored continuously so you cannot stock out prior to reordering.\nβ service level (type 2).\nThe β service level is a quantity-oriented performance measure describing the\nproportion of total demand within a reference period which is delivered without delay from stock on hand:\nformula_6\nThis is equal to the probability that an arbitrary demand unit is delivered without delay. This approach usually involves calculating a loss integral, whose values are tabulated for the normal distribution.\nBecause, contrary to the variations of the formula_7 service level, the\nformula_8 service level does not only reflect the stockout \"event\" but also the\n\"amount backordered\", it is widely used in industrial practice.\nAlso, by the definitions, comparing service levels we have formula_9 whenever the probability of zero demand equals 0.\nγ service level.\nThe γ service level, a time- and quantity-related performance criterion, serves to reflect not only the amount of backorders but also the waiting times of the demands backordered. The γ service level is defined as follows:\nformula_10\nThe γ service level is rarely used in industrial practice.\nTerminology.\nThe term \"Service Level Agreement\" (SLA) is frequently used for all aspects of a service level, but in more precise use one may distinguish:\nSLIs form the basis of SLOs, which in turn form the basis of SLAs. If an SLO is missed, customers will typically receive a credit or rebate, as stipulated by the SLA. A missed SLO is sometimes casually referred to as an \"SLA violation\", but this is actually within the scope of the SLA; if an SLA \"itself\" is violated (e.g., by not giving a rebate for a missed SLO), it is instead likely to result in a court case for breach of contract.", "Engineering,_Manufacturing": 0.999143064, "qwen": "Yes"}
{"id": "2554910", "revid": "45667218", "url": "https://en.wikipedia.org/wiki?curid=2554910", "title": "Safety stock", "text": "Safety stock is a term used by logisticians to describe a level of extra stock that is maintained to mitigate risk of stockouts (shortfall in raw material or packaging) caused by uncertainties in supply and demand. Adequate safety stock levels permit business operations to proceed according to their plans. Safety stock is held when uncertainty exists in demand, supply, or manufacturing yield, and serves as an insurance against stockouts.\nSafety stock is an additional quantity of an item held in the inventory to reduce the risk that the item will be out of stock. It acts as a buffer stock in case sales are greater than planned and/or the supplier is unable to deliver the additional units at the expected time.\nWith a new product, safety stock can be used as a strategic tool until the company can judge how accurate its forecast is after the first few years, especially when it is used with a material requirements planning (MRP) worksheet. The less accurate the forecast, the more safety stock is required to ensure a given level of service. With an MRP worksheet, a company can judge how much it must produce to meet its forecasted sales demand without relying on safety stock. However, a common strategy is to try to reduce the level of safety stock to help keep inventory costs low once the product demand becomes more predictable. That can be extremely important for companies with a smaller financial cushion or those trying to run on lean manufacturing, which is aimed towards eliminating waste throughout the production process.\nThe amount of safety stock that an organization chooses to keep on hand can dramatically affect its business. Too much safety stock can result in high holding costs of inventory. In addition, products that are stored for too long a time can spoil, expire, or break during the warehousing process. Too little safety stock can result in lost sales and, in the thus a higher rate of customer turnover. As a result, finding the right balance between too much and too little safety stock is essential.\nReasons for keeping safety stock.\nSafety stocks are mainly used in a \"make-to-stock\" manufacturing strategy, which is employed when the lead time of manufacturing is too long to satisfy the customer demand at the right cost/quality/waiting time.\nThe main goal of safety stocks is to absorb the variability of customer demand. Indeed, production planning is based on a forecast, which is (by definition) different from the real demand. By absorbing these variations, safety stock improves the customer-service level.\nCreating a safety stock will also delay stockouts from other variations, like an upward trend in customer demand, allowing time to adjust capacity.\nSafety stock is used as a buffer to protect organizations from stockouts caused by inaccurate planning or poor schedule adherence by suppliers. As such, its cost (in both material and management) is often seen as a drain on financial resources that results in reduction initiatives. In addition, time-sensitive goods such as food, drink, and other perishable items could spoil and go to waste if held as safety stock for too long. Various methods exist to reduce safety stock; these include better use of technology, increased collaboration with suppliers, and more accurate forecasting. In a lean supply environment, lead times are reduced, which can help minimize safety stock levels, thus reducing the likelihood and impact of stockouts.\nDue to the cost of safety stock, many organizations opt for a service level-led safety stock calculation; for example, a 95% service level could result in stockouts, but is at a level that is acceptable to the company. The lower the service level, the lower the requirement for safety stock.\nAn enterprise resource planning system (ERP system) can also help an organization reduce its level of safety stock. Most ERP systems provide a type of production planning module. An ERP module such as this can help a company develop highly accurate and dynamic sales forecasts and sales and operations plans. By creating more accurate and dynamic forecasts, a company reduces its chance of producing insufficient inventory for a given period, thus should be able to reduce the amount of safety stock required. In addition, ERP systems use established formulas to help calculate appropriate levels of safety stock based on the previously developed production plans. While an ERP system aids an organization in estimating a reasonable amount of safety stock, the ERP module must be set up to plan requirements effectively.\nInventory policy.\nThe size of the safety stock depends on the type of inventory policy in effect. An inventory node is supplied from a \"source\" which fulfills orders for the considered product after a certain replenishment lead time. In a periodic inventory policy, the inventory level is checked periodically (such as once a month) and an order is placed at that time as to meet the expected demand until the next order. In this case, the safety stock is calculated considering the demand and supply variability risks during this period plus the replenishment lead time. If the inventory policy is continuous policy (such as an order point-order quantity policy or an order point-order up to policy) the inventory level is continuously monitored and orders are placed with freedom of time. In this case, safety stock is calculated considering the risk of only the replenishment lead time. If applied correctly, continuous inventory policies can lead to smaller safety stock whilst ensuring higher service levels, in line with lean processes and more efficient overall business management. However, continuous inventory policies are much harder to implement, so most of the organisations using traditional planning processes and tools opt for periodic inventory policy.\nMethods for calculating safety stocks.\nReorder point method with demand and lead time uncertainty for type I service.\nA commonly used approach calculates the safety stock based on the following factors:\nAssuming that demand during successive unit time periods are independent and identically distributed random variables drawn from a normal distribution, the safety stock can be calculated as:formula_1where,\nThe reorder point can then be calculated as:formula_10The first term in the ROP formula formula_11 is the average demand during the lead time. The second term formula_12 is the safety stock. If the lead time is deterministic, i.e. formula_13, then the ROP formula is simplified as formula_14.\nIssues with this approach.\nNo universal formula exists for safety stock, and application of the one above can cause serious damage.\nIt makes several implicit assumptions:\nType II service.\nAnother popular approach described by Nahmias uses the standardized unit loss integral L(z), given by:\nformula_15\nWhere formula_16 is cumulative distribution function for the standard normal. Let β be the proportion of demands met from stock (service level), Q the order quantity and σ the standard deviation of demand, then the following relationship holds:\nformula_17\nIn this case, the safety stock is given by:\nformula_18\nand the expected number of units out of stock during an order cycle is given by σL(z).\nReferences.\n\"This is a dead link", "Engineering,_Manufacturing": 0.9998481274, "qwen": "Yes"}
{"id": "2559879", "revid": "15574806", "url": "https://en.wikipedia.org/wiki?curid=2559879", "title": "Ceramic forming techniques", "text": "Ceramic forming techniques are ways of forming ceramics, which are used to make everything from tableware such as teapots to engineering ceramics such as computer parts. Pottery techniques include the potter's wheel, slip casting and many others. \nMethods for forming powders of ceramic raw materials into complex shapes are desirable in many areas of technology. For example, such methods are required for producing advanced, high-temperature structural parts such as heat engine components, recuperators and the like from powders of ceramic raw materials. Typical parts produced with this production operation include impellers made from stainless steel, bronze, complex cutting tools, plastic mould tooling, and others. Typical materials used are: wood, metal, water, plaster, epoxy and STLs, silica, and zirconia.\nThis production operation is well known for providing tools with dimensional stability, surface quality, density and uniformity. For instance, on the slip casting process the cast part is of high concentration of raw materials with little additive, this improves uniformity. But also, the plaster mould draws water from the poured slip to compact and form the casting at the mould surface. This forms a dense cast.\nSlip casting.\nThere are many forming techniques to make ceramics, but one example is slip casting. This is where slip or, liquid clay, is poured into a plaster mould. The water in the slip is drawn out into the walls of the plaster mould, leaving an inside layer of solid clay, which hardens quickly. When dry, the solid clay can then also be removed. The slip used in slip casting is often liquified with a substance that reduces the need for additional water to soften the slip (unless crazing is wanted); this prevents excessive shrinkage which occurs when a piece containing a lot of water dries; another approach is to dry items slowly.\nSlip-casting methods provide superior surface quality, density and uniformity in casting high-purity ceramic raw materials over other ceramic casting techniques, such as hydraulic casting, since the cast part is a higher concentration of ceramic raw materials with little additives. A slip is a suspension of fine raw materials powder in a liquid such as water or alcohol with small amounts of secondary materials such as dispersants, surfactants and binders. Pottery slip casting techniques employ a plaster block or flask mould. The plaster mould draws water from the poured slip to compact and form the casting at the mould surface. This forms a dense cast removing deleterious air gaps and minimizing shrinkage in the final sintering process.\nAdditive manufacturing.\nFor the production of complex shapes in small quantities, additive manufacturing (AM) represents an effective approach, and is the subject of significant research and development. Unlike the additive manufacturing of polymeric materials, the scope of AM of ceramics remains quite limited owing to materials processing challenges. Commercially available equipment for the AM of ceramics mostly relies on layer by layer sintering of powders and is rarely cost-effective. However, the difficulties in machining ceramic articles means that AM techniques can be attractive in situations where production volumes are too low to viably produce molds for slip casting methods. In particular the additive manufacturing of ceramics from preceramic polymers using techniques including stereolithography, with subsequent pyrolysis to yield polymer derived ceramics, represents an emerging approach to tackling the challenge of additively manufactured ceramics. \nCeramic shell casting.\nCeramic shell casting techniques using silica, zirconia and other refractory materials are currently used by the metal parts industry for 'net casting', forming precision shell moulds for molten metal casting. The technique involves a successive wet dipping and dry powder coating or stucco to build up the mould shell layer. The shell casting method in general is known for dimensional stability and is used in many net-casting processes for aerospace and other industries in molten metal casting. Automated facilities use multiple wax patterns on trees, large slurry mixers and fluidic powder beds for automated dipping.\nTechnical ceramics.\nWhen forming technical ceramic materials from dry powders prepared for processing, the method of forming into the shape required depends upon the method of material preparation and size and shape of the part to be formed. Materials prepared for dry powder forming are most commonly formed by \"dry\" pressing in mechanical or hydraulic powder compacting presses selected for the necessary force and powder fill depth. Dry powder is automatically discharged into the non-flexible steel or tungsten carbide insert in the die and punches then compact the powder to the shape of the die. If the part is to be large and unable to have pressure transmit suitably for a uniform pressed density then isostatic pressing may be used. When isostatically pressed the powder takes the shape of a flexible membrane acting as the mould, forming the shape and size of the pressed powder. Isostatic presses can be either high speed, high output type of automatic presses for such parts as ceramic insulators for spark plugs or sand blast nozzles, or slower operating \"wet bag\" presses that are much more manual in operation but suitable particularly for large machinable blanks or blanks that will be cut or otherwise formed in secondary operations to the final shape. \nIf technical ceramic parts are needed where the length to diameter ratio is very large, extrusion may be used. There are two types of ceramic extruders one being piston type with hydraulic force pushing a ram that in turn is pushing the ceramic through the loaded material cylinder to and through the die which forms the extrudate. The second type of extruder is a screw, or auger, type where a screw turns forcing the material to and through the die which again shapes the part. In both types of extrusion the raw material must be plasticized to allow and induce the flow of the material in the process. \nComplex technical ceramic parts are commonly formed using either the injection moulding process or \"hot wax moulding.\" Both rely on heat sensitive plasticizers to allow material flow into a die. The part is then quickly cooled for removal from the die. Ceramic injection moulding is much like plastic injection moulding using various polymers for plasticizing. Hot wax moulding largely uses paraffin wax.\nOther techniques.\nThere are also several traditional techniques of handbuilding, such as pinching, soft slab, hard slab, and coil construction. \nOther techniques involve threading animal or artificial wool fiber through paperclay slip, to build up layers of material. The result can be wrapped over forms or cut, dried and later joined with liquid and soft paperclay.\nWhen forming very thin sheets of ceramic material, \"tape casting\" is commonly used. This involves pouring the slip (which contains a polymer \"binder\" to give it strength) onto a moving carrier belt, and then passing it under a stationary \"doctor blade\" to adjust the thickness. The moving slip is then air dried, and the \"tape\" thus formed is peeled off the carrier belt, cut into rectangular shapes, and processed further. As many as 100 tape layers, alternating with conductive metal powder layers, can be stacked up. These are then sintered (\"fired\") to remove the polymer and thus make \"multilayer\" capacitors, sensors, etc. According to D. W. Richerson of the American Ceramic Society, more than a billion of such capacitors are manufactured every day. (About 100 are in a typical cellular telephone, and about a thousand in a typical automobile.)\nGel casting is another technique used to create engineering ceramics.", "Engineering,_Manufacturing": 1.0000081062, "qwen": "Yes"}
{"id": "11054590", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=11054590", "title": "Atlas Machine and Supply, Inc.", "text": "Atlas Machine and Supply, Inc., founded in 1907, is one of the largest heavy-capacity industrial machinery engineering, manufacturing and remanufacturing centers in the United States. The firm also designs and repairs industrial compressed air systems compressors and related equipment, and offers full compressor rebuilding and rental engineering capabilities. The company had 210 employees as of January 2015. The headquarters are in Louisville, Kentucky, highlighted by a 100,000 sq. ft. facility. Additional plants and repair centers are located in Cincinnati, Ohio, Columbus, Ohio, and in Evansville, Indiana. In 2014 Atlas opened its fifth location, in Indianapolis, Indiana.\nIn 2014 Richard Gimmel III became the fourth generation of his family to lead the company as president when his father, Richard Gimmel, Jr., became chairman. The Gimmel family immigrated from Switzerland to Louisville in the 1870s.\nAtlas began operations manufacturing elevators at a small shop in downtown Louisville, and gradually expanded its machine shop and industrial engineering capabilities. Atlas became a Gardner Denver compressor distributor in the 1940s.\nThe company's manufacturing facilities now focus on the repair, design, and remanufacturing of heavy industrial machinery.\nIn 2011, Atlas launched a field machining division that mirrors its machine shop capabilities for customers with on-site repair needs.\nAtlas added a new Laser Tracking metrology service in 2012 which allows for completing large-scale machining jobs on-site.\nThe company has been a beneficiary of the movement by U.S. manufacturers toward outsourcing functions that used to be performed internally, e.g., plant equipment maintenance, engineering, and machinery modification, as well as the recent groundswell in reshoring efforts in U.S. manufacturing.\nIn 2012, Atlas Machine had more than 3,000 industrial customers throughout North America but concentrated in the Midwest and the Ohio Valley.", "Engineering,_Manufacturing": 0.9953098297, "qwen": "Yes"}
{"id": "8726298", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=8726298", "title": "Clinching", "text": "In metalworking, clinching or press-joining is a bulk sheet metal forming process aimed at joining thin metal sheets without additional components, using special tools to plastically form an interlock between two or more sheets. The process is generally performed at room temperature, but in some special cases the sheets can be pre-heated to improve the material ductility and thereby avoid the formation of cracks during the process. Clinching is characterized by a series of advantages over competitive technologies:\nTools.\nBecause the process involves relatively low forces (ranging from 5 to 50 kN depending on the material to join, type of tools and sheet thicknesses), clinching generally involves reduced size (often portable) machines. The tools typically consist of a punch and a die. Different tools have been developed so far, which can be classified in round and rectangular tools. Round clinching tools include: fixed grooved dies, split dies (with 2–4 movable sectors) and flat dies. Such tools produce round joints which show almost identical mechanical behaviors in all plane directions. When round tools are adopted, the integrity of the sheet in the joint must be guaranteed in order to preserve a good mechanical behavior of the joints.\nOn the other hand, rectangular clinched joints exhibit behaviors which depend on the loading direction and both sheets are intentionally sheared along the \"long direction\" in order to produce the interlock. The choice of the tools is highly influenced by:\nIn addition, the choice of the clinching tools highly affects the joining strength and the absorbed energy of a clinched connection other than the joining force. Rectangular tools, for example, require lower joining forces than round tools since the material shearing, while among the round clinching tools split dies require the minimum joining force and the largest interlock.\nOne benefit of clinching is the capability to join prepainted sheet metal commonly used in the appliance industry without damaging the painted surface. Clinching is an important means of fastening aluminum panels, such as hoods and decklids, in the automotive industry, due to the difficulty of spot welding of aluminum.\nMain advantages as compared to welding.\nClinching is used primarily in the automotive, appliance and electronic industries, where it often replaces spot welding. Clinching does not require electricity or cooling of the electrodes commonly associated with spot welding. Being a mechanical joining process, clinching can be used to join materials showing no electrical conductivity such as polymers or plastic-metal composites. In addition, it does not require a substrate preparation such as pre-cleaning of surfaces which is required for welding processes. This fact contributes to reduce the joining costs and the environmental impact (since chemical cleaning is not required).\nClinching does not generate sparks or fumes. The strength of a clinched joint can be tested non-destructively using a simple measuring instrument to measure the remaining thickness at the bottom of the joint, of the diameter of the produced button depending on the type of tools employed. Life expectancy for clinching tools is in the hundreds of thousands of cycles, making it an economical process. Clinched connections performed on aluminum sheets have higher fatigue life as compared to spot welding.\nMain advantages as compared to adhesive joining.\nClinching does not require a pre-cleaning of the surfaces, which is needed before applying adhesives. Clinching is almost an instant joining process (the required joining time is lower than a second) while adhesive joining often requires a much longer time mainly owing to the curing of the joint (up to many hours). Clinched joints are less affected by environmental agents and effect of aging.\nMain limitations.\nBecause it is based on the plastic deformation of the sheets, clinching is limited by the sheet material formability (ductility). Metal ductility increases with temperature, so heat assisted clinching processes have been developed, extending the clinching \"joinability\". Increasing the joining temperature reduces the material's yield stress, so that less joining force is required. Different heating systems are used to heat the sheets before clinching:\nProlonged heating can increase the grain size or cause metallurgical changes in alloys, which can alter the mechanical behavior of the material at the joint site.\nMaterials.\nClinching has been widely employed for joining ductile metals, including the following:\nIt has recently extended to other metals, such as:\nIt has also extended to non-metallic materials, such as:", "Engineering,_Manufacturing": 0.999905467, "qwen": "Yes"}
{"id": "8735197", "revid": "46188090", "url": "https://en.wikipedia.org/wiki?curid=8735197", "title": "Koyo Seiko", "text": "Koyo Seiko (Osaka, Japan) was established as a private company by Zenichiro Ikeda in 1921. They initially sold imported bearings but by 1935 had begun production of Koyo branded bearings under the name Koyo Seiko Co., Ltd.\nKoyo merged with Toyoda Machinery Jan. 1, 2006, to become JTEKT, a leading manufacturer of ball and roller bearings, automotive steering systems, drive line products and machine tools.\nToyota Motor Corp. had been the major investor in each company and is the major stockholder in JTEKT with about 24 percent. \nKoyo Seiko has various bearing manufacturing facilities all around the world. There are manufacturing sites in Japan, UK, Europe, China and India.\nKoyo is a member of World Bearing Association (WBA).", "Engineering,_Manufacturing": 1.0000087023, "qwen": "Yes"}
{"id": "29744058", "revid": "28362544", "url": "https://en.wikipedia.org/wiki?curid=29744058", "title": "Bottle recycling", "text": "Bottles are able to be recycled and this is generally a positive option. Bottles are collected via kerbside collection or returned using a bottle deposit system. Currently just over half of plastic bottles are recycled globally. About 1 million plastic bottles are bought around the world every minute and only about 50% are recycled.\nGlass bottles.\nThere are a large number of benefits to recycling glass bottles, not only for the manufacturing of new bottles but also for the production of other materials that can be used in different contexts. Clean glass bottles are 100% recyclable, can be substituted for up to 95% of raw material, and can be recycled ad-infinitum without the loss of purity or quality. Recycled glass also has a variety of uses outside of the production of new bottles. The least beneficial of these uses is when glass bottles are sifted, crushed down, and mixed with food refuse to create dirty mixed cullet. Mixed cullet has few uses outside of being used as and alternative to traditional landfill daily cover. Alternatively, smaller and unrecoverable pieces of glass are ground down into a fine powder and used as a high grade sand alternative for the production of concrete. \nRecoverable glass is often sorted by colour as different colour glass has a variety of uses and values. In the United States, recovered green glass is primarily shipped to Europe to produce wine bottles, brown glass is sold domestically to beer bottlers, and clear glass, the most valuable of the three can be used to replace up to 30 percent of virgin material in the production of new glass. In recent years, extended producer responsibility (has come to the forefront of the debate concerning glass bottle recycling due to glass being very easy to clean and reuse, and its innate cradle to cradle design properties. Recycled glass is a necessity, as without it, manufacturers would not be able to keep up with the demand for new glass containers. \nRecycling one glass bottle can save enough energy to power a computer for 25 minutes. In fact for every 10% of cullet added to the production of a new bottle, energy usage goes down by 3-4%. Recycling one ton of glass can save approximately 42 kWh of energy which translates to 7.5 pounds of air pollutants not being released into the atmosphere. \nPET bottles.\nPET bottles are mostly recycled as a raw material. In many countries, PET plastics are coded with the resin identification code number \"1\" inside the universal recycling symbol, usually located on the bottom of the container.\nHDPE bottles.\nHDPE is commonly used in bottles, particularly bottles (or jugs) of milk. Recycling code 2 is applicable. In the US, only about 30-35% of HDPE bottles are recycled.\nLegislation.\nContainer deposit legislation are laws passed by city, state, provincial, or national governments. They require a deposit on bottles to be collected when sold and reimbursed when returned.\nIn May 2018 the Israeli Ministry Impose EUR 12 m Fine on Bottle Manufacturers and Importers that Didn't Meet Collection Targets.\nEnvironmental comparisons.\nMany potential factors are involved in environmental comparisons of returnable vs non-returnable systems. Researchers have often used life cycle analysis methodologies to balance the many diverse considerations. Often the comparisons show benefits and problems with all alternatives. It helps provide an objective view of a complex subject.\nReuse of bottles requires a reverse logistics system, cleaning and, sanitizing bottles, and an effective Quality Management System. A key factor with glass milk bottles is the number of cycles of uses to be expected. Breakage, contamination, or other loss reduces the benefits of returnables. A key factor with one-way recyclables is the recycling rate: In the US, only about 30-35% of HDPE bottles are recycled.\nReferences.\nהמשרד להגנת הסביבה", "Engineering,_Manufacturing": 0.9970234632, "qwen": "Yes"}
{"id": "29747083", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=29747083", "title": "Signode Finland", "text": "Signode Finland, former Oy M. Haloila Ab, is one of the world's leading companies in the manufacture of pallet-wrapping machines. Signode Finland factories are located in Masku, Finland (fully automatic wrapping machines) and Kardjali, Bulgaria (semi-automatic wrapping machines).\nWrapping Machines.\nSignode semi-automatic and fully automatic Octopus wrapping machines are used for wrapping different kinds of pallet loads for example, in the food, beverage and construction industries, and in logistics centres.\nThe most widely known product in Signode Finland's product range is the fully automatic wrapping machine, Octopus, with over 7000 fully automatic stretch wrapping machines manufactured so far. In 2008, the international media also spotlighted the manufacture of the 3000th Octopus machine.\nThe Octopus machines have been in production since 1983; when the model was launched it was the first pallet-wrapping machine with a rotating ring system. In 2013 the company celebrated the 30th anniversary of the Octopus range. Octopus is still the market leader at the international level and one of the most widely known brands in the wrapping industry.\nSemi-automatic wrapping machines include the Cobra, Ecomat and Rolle.\nHistory.\nHaloila was founded in 1972. The first rotary stretch wrapping machines were manufactured in 1976 and in 1983 Haloila introduced the first fully automatic Octopus wrapping machine. Illinois Tool Works Inc. (ITW) purchased Haloila in 1995 and in 2014 Haloila became part of the Signode Industrial Group. In October 2020 Oy M. Haloila Ab changed company name to Signode Finland Oy.", "Engineering,_Manufacturing": 0.9999990463, "qwen": "Yes"}
{"id": "22590756", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=22590756", "title": "Thermal profiling", "text": "A thermal profile is a complex set of time-temperature data typically associated with the measurement of thermal temperatures in an oven (ex: reflow oven). The thermal profile is often measured along a variety of dimensions such as slope, soak, time above liquidus (TAL), and peak.\nA thermal profile can be ranked on how it fits in a process window (the specification or tolerance limit). Raw temperature values are normalized in terms of a percentage relative to both the process mean and the window limits. The center of the process window is defined as zero, and the extreme edges of the process window are ±99%. A Process Window Index (PWI) greater than or equal to 100% indicates the profile is outside of the process limitations. A PWI of 99% indicates that the profile is within process limitations, but runs at the edge of the process window. For example, if the process mean is set at 200 °C with the process window calibrated at 180 °C and 220 °C respectively, then a measured value of 188 °C translates to a process window index of −60%.\nThe method is used in a variety of industrial and laboratory processes, including electronic component assembly, optoelectronics, optics, biochemical engineering, food science, decontamination of hazardous wastes, and geochemical analysis.\nSoldering of electronic products.\nOne of the major uses of this method is soldering of electronic assemblies. There are two main types of profiles used today: The Ramp-Soak-Spike (RSS) and the Ramp to Spike (RTS). In modern systems, quality management practices in manufacturing industries have produced automatic process algorithms such as PWI, where soldering ovens come preloaded with extensive electronics and programmable inputs to define and refine process specifications. By using algorithms such as PWI, engineers can calibrate and customize parameters to achieve minimum process variance and a near zero defect rate.\nReflow process.\nIn soldering, a thermal profile is a complex set of time-temperature values for a variety of process dimensions such as slope, soak, TAL, and peak. Solder paste contains a mix of metal, flux, and solvents that aid in the phase change of the paste from semi-solid, to liquid to vapor; and the metal from solid to liquid. For an effective soldering process, soldering must be carried out under carefully calibrated conditions in a reflow oven. Convection Reflow Oven Detailed Description\nThere are two main profile types used today in soldering: \nRamp-Soak-Spike.\nRamp is defined as the rate of change in temperature over time, expressed in degrees per second. The most commonly used process limit is 4 °C/s, though many component and solder paste manufacturers specify the value as 2 °C/s. Many components have a specification where the rise in temperature should not exceed a specified temperature per second, such as 2 °C/s. Rapid evaporation of the flux contained in the solder paste can lead to defects, such as lead lift, tombstoning, and solder balls. Additionally, rapid heat can lead to steam generation within the component if the moisture content is high, resulting in the formation of microcracks.\nIn the soak segment of the profile, the solder paste approaches a phase change. The amount of energy introduced to both the component and the PCB approaches equilibrium. In this stage, most of the flux evaporates out of the solder paste. The duration of the soak varies for different pastes. The mass of the PCB is another factor that must be considered for the soak duration. An over-rapid heat transfer can cause solder splattering and the production of solder balls, bridging and other defects. If the heat transfer is too slow, the flux concentration may remain high and result in cold solder joints, voids and incomplete reflow.\nAfter the soak segment, the profile enters the ramp-to-peak segment of the profile, which is a given temperature range and time exceeding the melting temperature of the alloy. Successful profiles range in temperature up to 30 °C higher than liquidus, which is approximately 183 °C for eutectic and approximately 217 °C for lead-free.\nThe final area of this profile is the cooling section. A typical specification for the cool down is usually less than −6 °C/s (falling slope).\nRamp-to-Spike.\nThe Ramp to Spike (RTS) profile is almost a linear graph, starting at the entrance of the process and ending at the peak segment, with a greater Δt (change in temperature) in the cooling segment. While the Ramp-Soak-Spike (RSS) allows for about 4 °C/s, the requirements of the RTS is about 1–2 °C/s. These values depend on the solder paste specifications. The RTS soak period is part of the ramp and is not as easily distinguishable as in RSS. The soak is controlled primarily by the conveyor speed. The peak of the RTS profile is the endpoint of the linear ramp to the peak segment of the profile. The same considerations about defects in an RSS profile also apply to an RTS profile.\nWhen the PCB enters the cooling segment, the negative slope generally is steeper than the rising slope.\nThermocouple attachments.\nThermocouples (or TCs) are two dissimilar metals joined by a welded bead. For a thermocouple to read the temperature at any given point, the welded bead must come in direct contact with the object whose temperatures need to be measured. The two dissimilar wires must remain separate, joined only at the bead; otherwise, the reading is no longer at the welded bead but at the position where the metals first make contact, rendering the reading invalid.\nA zigzagging thermocouple reading on a profile graph indicates loosely attached thermocouples. For accurate readings, thermocouples are attached to areas that are dissimilar in terms of mass, location and known trouble spots. Additionally, they should be isolated from air currents. Finally, the placement of several thermocouples should range from populated to less populated areas of the PCB for the best sampling conditions.\nSeveral methods of attachment are used, including epoxy, high-temperature solder, Kapton and aluminum tape, each with various levels of success for each method.\nEpoxies are good at securing TC conductors to the profile board to keep them from becoming entangled in the oven during profiling. Epoxies come in both insulator and conductor formulations The specs need to be checked otherwise an insulator can play a negative role in the collection of profile data. The ability to apply this adhesive in similar quantities and thicknesses is difficult to measure in quantitative terms. This decreases reproducibility. If epoxy is used, properties and specifications of that epoxy must be checked. Epoxy functions within a wide range of temperature tolerances.\nThe properties of solder used for TC attachment differ from that of electrically connective solder. High temperature solder is not the best choice to use for TC attachment for several reasons. First, it has the same drawbacks as epoxy – the quantity of solder needed to adhere the TC to a substrate varies from location to location. Second, solder is conductive and may short-circuit TCs. Generally, there is a short length of conductor that is exposed to the temperature gradient. Together, this exposed area, along with the physical weld produce an Electromotive Force (EMF). Conductors and the weld are placed in a homogeneous environment within the temperature gradient to minimize the effects of EMF.\nKapton tape is one of the most widely used tapes and methods for TC and TC conductor attachment. When several layers are applied, each layer has an additive effect on the insulation and may negatively impact a profile. A disadvantage of this tape is that the PCB has to be very clean and smooth to achieve an airtight cover over the thermocouple weld and conductors. Another disadvantage to Kapton tape is that at temperatures above 200 °C the tape becomes elastic and, hence, the TCs have a tendency to lift off the substrate surface. The result is erroneous readings characterized by jagged lines in the profile.\nAluminum tape comes in various thicknesses and density. Heavier aluminum tape can defuse the heat transfer through the tape and act as an insulator. Low density aluminum tape allows for heat transfer to the EMF-producing area of the TC. The thermal conductivity of the aluminum tape allows for even conduction when the thickness of the tape is fairly consistent in the EMF-producing area of the thermocouple.\nVirtual profiling.\nVirtual profiling is a method of creating profiles without attaching the thermocouples (TCs) or having to physically instrument a PCB each and every time a profile is run for the same production board. All the typical profile data such as slope, soak, TAL, etc., that are measured by instrumented profiles are gathered by using virtual profiles. The benefits of not having attached TCs surpass the convenience of not having to instrument a PCB every time a new profile is needed.\nVirtual profiles are created automatically, for both reflow or wave solder machines. An initial recipe setup is required for modeling purposes, but once completed, profiling can be made virtual. As the system is automatic, profiles can be generated periodically or continuously for each and every assembly. SPC charts along with CpK can be used as an aid when collecting a mountain of process-related data. Automated profiling systems continuously monitor the process and create profiles for each assembly. As barcoding becomes more common with both reflow and wave processes, the two technologies can be combined for profiling traceability, allowing each generated profile to be searchable by barcode. This is useful when an assembly is questioned at some time in the future. As a profile is created for each assembly, a quick search using the PCB’s barcode can pull up the profile in question and provide evidence that the component was processed in spec. Additionally, tighter process control can be achieved when combining automated profiling with barcoding, such as confirming that the correct process has been input by the operator before launching a production run.", "Engineering,_Manufacturing": 0.9999555349, "qwen": "Yes"}
{"id": "22597311", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=22597311", "title": "AILU", "text": "The Association of Industrial Laser Users (AILU) was established in 1995 as an independent, non-profit organisation run by and for laser users involved in activities including manufacturing, healthcare, academic and industrial research; as well as suppliers of laser-related products and services.\nThe association promotes many activities surrounding Laser use, such as the fostering of co-operation and collaboration and the dissemination of information, experience and expertise relating to industrial laser technology, laser materials processing; its applications and related technologies.\nOrganisation.\nThe organisation of AILU is under the direction of an elected standing committee made up of representatives from the UK industrial laser community. Elections are held annually at the Annual General Meeting.\nAILU provides a wide range of general services to laser users and suppliers and hosts a number of special interest groups (SIGs) to better support members who have particular interests in common. These include a Job Shop SIG (established in 1995, with 86 members) for subcontract laser-based engineering companies; a Market Development SIG (established in 2005, with 240 members) for suppliers of laser-related products and services; a Medical SIG (established in 2007, with 55 members) for clinicians, manufacturers using lasers for manufacture of medical devices and suppliers of laser-related products and services; and the Micro:Nano SIG, AILU's newest, launched in mid 2008 at AILU's 10th microprocessing workshop.”\nActivities.\nThe current activities of AILU include:\nAILU’s Membership.\nApplication for membership of AILU is open to the industrial laser community worldwide. AILU currently has over 300 members, which make up (by sector) manufacturing industry including laser job shops (40%), suppliers of laser-related products and services (30%) and research and consultancy organisations (25%).\nThe AILU Award.\nThe AILU award recognises those individuals who have made an outstanding contribution to the industrial use of lasers in the UK. The AILU Award is presented to an individual for significant contribution to laser materials processing and that preferably has wider benefit for the industrial laser user community.", "Engineering,_Manufacturing": 0.9987491965, "qwen": "Yes"}
{"id": "30295206", "revid": "22651524", "url": "https://en.wikipedia.org/wiki?curid=30295206", "title": "Laser guided and stabilized arc welding", "text": "Laser guided and stabilized welding (LGS-welding) is a process in which a laser beam irradiates an electrical heated plasma arc to set a path of increased conductivity. Therefore, the arc's energy can be spatial directed and the plasma burns more stable. The process must be distinguished from laser-hybrid welding, since only low power laser energy of a couple hundred Watts is used and the laser does not contribute significantly to the welding process in terms of energy input.\nOperation.\nThe principle of laser enhanced welding is based on the interaction between the electrical arc and laser radiation. Due to the optogalvanic effect (OGE) a channel of higher conductivity in the plasma is established along the path of the laser. Therefore, a movement of the laser beam results in a movement of the electrical arc. This effect is limited to a range of some millimeters, but shows the influence of the radiation to the plasma. A raise of welding speed of over 100% is described by using a diode laser with a wavelength of 811 nm without a significant loss in penetration depth. Furthermore, this technique is used in cladding. Depending on the welded material argon or argon with CO2 is used as shielding gas. The laser source must be tuned to emit at a wavelength of 811 nm and is focused into the plasma.\nLaser guided and stabilized GMA-Welding.\nThe process is used for welding thin metal sheets up to about 2 mm when welding in overlap or butt joint. LGS-GMA-welding is most advantageous when welding fillet welds. The guidance effect of the laser radiation forces the arc into the fillet. Therefore, a steady seam can be reached. Furthermore, the stabilization of the plasma enables the GMA-process to weld thin sheets without burning holes in the material.\nEquipment and setup.\nThe setup requires the GMA welding head tilted at 60° to the work piece surface. In order to realize a maximum overlap between the electric arc and the laser beam in the process area, the laser is installed upright to the workpiece and focused in the electrical arc. Standard welding equipment can be used for the process. The laser source is described above.\nLaser guided and stabilized double head TIG-welding.\nIn laser guided and stabilized double head TIG-welding the laser forces two arcs together. The goal of this technique is to increase the welding speed of TIG-welding without compromising the quality.\nEquipment and setup.\nFor this process two TIG-sources are needed and the laser described above. The TIG-torches are set up with the laser beam perpendicular in the middle. All welding modes of the two torches are possible (DC/DC, AC/AC, AC/DC).\nLaser guided and stabiliszed GMA-Cladding.\nIn LGS-GMA-cladding the stabilization effect is used enable the GMA-process to work with low energy. This is needed to reduce the penetration depth and therefore the dilution of base and deposition material. The combination of GMA-welding and a diode laser leads to a cheap and energy efficient process.\nEquipment and setup.\nThe setup for the LGS-GMA-cladding is almost alike the one for LGS-GMA-welding beside that the GMA-source needs to have a \"Cold-MIG\" process. This means, that the welding current is controlled my microcontrollers and produced by power electronics. That way not only the current peaks can be controlled, but also the slopes.", "Engineering,_Manufacturing": 1.0000072718, "qwen": "Yes"}
{"id": "3432530", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=3432530", "title": "Cutting tool (machining)", "text": "In the context of machining, a cutting tool or cutter is typically a hardened metal tool that is used to cut, shape, and remove material from a workpiece by means of machining tools as well as abrasive tools by way of shear deformation. The majority of these tools are designed exclusively for metals. \nThere are several different types of single-edge cutting tools that are made from a variety of hardened metal alloys that are ground to a specific shape in order to perform a specific part of the turning process resulting in a finished machined part. Single-edge cutting tools are used mainly in the turning operations performed by a lathe in which they vary in size as well as alloy composition depending on the size and the type of material being turned. These cutting tools are held stationary by what is known as a \"tool post\", which is what manipulates the tools to cut the material into the desired shape. Single-edge cutting tools are also the means of cutting material performed by shaping machines and planing machines, which remove material by means of one cutting edge. \nMilling and drilling tools are often multipoint tools. Drilling is exclusively used to make holes in a workpiece. All drill bits have two cutting edges that are ground into two equally tapered angles which cuts through the material by applying downward rotational force. Endmills or milling bits, which also cut material by rotational force. Although these tools are not made to put holes in a workpiece. They cut by horizontal shear deformation in which the workpiece is brought into the tool as it's rotating. This is known as the tool path which is determined by the axis of the table that is holding the workpiece in place. This table is designed to accept a variety of vises and clamping tools so that it can move into the cutter at various angles and directions while the workpiece remains still. There are several different types of endmills that perform a certain type of milling action. \nGrinding stones are tools that contain several different cutting edges which encompasses the entirety of the stone. Unlike metallic cutting tools, these grinding stones never go dull. In fact the formation of cutting edges of metallic cutting tools are achieved by the use of grinding wheels and other hard abrasives. There are several different types of grinding stone wheels that are used to grind several different types of metals. Although these stones are not metal, they need to be harder than the metal that they grind. In contrast to the grinding stone, if the hardness of the metal exceeds that of the stone, the metal will cut the stone. This is not ideal. Each grain of abrasive functions as a microscopic single-point cutting edge (although of high negative rake angle), and shears a tiny chip. \nCutting tool materials must be harder than the material which is to be cut, and the tool must be able to withstand the heat and force generated in the metal-cutting process. Also, the tool must have a specific geometry, with clearance angles designed so that the cutting edge can contact the workpiece without the rest of the tool dragging on the workpiece surface. The angle of the cutting face is also important, as is the flute width, number of flutes or teeth, and margin size. In order to have a long working life, all of the above must be optimized, plus the speeds and feeds at which the tool is run.\nTypes.\nLinear cutting tools include tool bits (single-point cutting tools) and broaches. Rotary cutting tools include drill bits, countersinks and counterbores, taps and dies, reamers, and cold saw blades. Other cutting tools, such as bandsaw blades, hacksaw blades, and fly cutters, combine aspects of linear and rotary motion \nCutting tools with inserts (indexable tools).\nCutting tools are often designed with inserts or replaceable tips (tipped tools). In these, the cutting edge consists of a separate piece of material, either brazed, welded or clamped on to the tool body. Common materials for tips include cemented carbide, polycrystalline diamond, and cubic boron nitride. Tools using inserts include milling cutters (endmills, fly cutters), tool bits, and saw blades.\nTool setup.\nThe detailed instructions of how to combine the tool assembly out of basic holder, tool and insert can be stored in a tool management solution.\nCutting edge.\nThe cutting edge of a cutting tool is a very important for the performance of the cutting process. The main features of the cutting edge are:\nThe measurement of the cutting edge is performed using a tactile instrument or an instrument using focus variation. To quantify a cutting edge the following parameters are used:\nOne of the most important cutting edge parameters is the K factor. It specifies the form of the cutting edge. 1 means a symmetric cutting edge. If the value is smaller than 1 the form is called a waterfall. If the value is larger than 1 it is called a trumpet. Depending on the material being cut, feed rate and other factors, a cutting tool with the optimum K factor should be used.", "Engineering,_Manufacturing": 1.0000035763, "qwen": "Yes"}
{"id": "3435954", "revid": "3727527", "url": "https://en.wikipedia.org/wiki?curid=3435954", "title": "Chassis ground", "text": "A chassis ground is a link between different metallic parts of a machine to ensure an electrical connection between them. Examples include electronic instruments and motor vehicles.\nConfusion.\nThe chassis must not be considered as a link to Earth. Depending on the usage of electrical machines, this may or may not be the case. For example, in all cars metallic parts are linked together but they are not linked to the Earth. This explains why one can experience electrical discharge when leaving a car.", "Engineering,_Manufacturing": 0.9999393225, "qwen": "Yes"}
{"id": "3437506", "revid": "1461430", "url": "https://en.wikipedia.org/wiki?curid=3437506", "title": "Routing (electronic design automation)", "text": "In electronic design, wire routing, commonly called simply routing, is a step in the design of printed circuit boards (PCBs) and integrated circuits (ICs). It builds on a preceding step, called placement, which determines the location of each active element of an IC or component on a PCB. After placement, the routing step adds wires needed to properly connect the placed components while obeying all design rules for the IC. Together, the placement and routing steps of IC design are known as place and route.\nThe task of all routers is the same. They are given some pre-existing polygons consisting of pins (also called terminals) on cells, and optionally some pre-existing wiring called preroutes. Each of these polygons are associated with a net, usually by name or number. The primary task of the router is to create geometries such that all terminals assigned to the same net are connected, no terminals assigned to different nets are connected, and all design rules are obeyed. A router can fail by not connecting terminals that should be connected (an open), by mistakenly connecting two terminals that should not be connected (a short), or by creating a design rule violation. In addition, to correctly connect the nets, routers may also be expected to make sure the design meets timing, has no crosstalk problems, meets any metal density requirements, does not suffer from antenna effects, and so on. This long list of often conflicting objectives is what makes routing extremely difficult.\nAlmost every problem associated with routing is known to be intractable. The simplest routing problem, called the Steiner tree problem, of finding the shortest route for one net in one layer with no obstacles and no design rules is NP-hard if all angles are allowed and NP-complete if only horizontal and vertical wires are allowed. Variants of channel routing have also been shown to be NP-complete, as well as routing which reduces crosstalk, number of vias, and so on.\nRouters therefore seldom attempt to find an optimum result. Instead, almost all routing is based on heuristics which try to find a solution that is good enough.\nDesign rules sometimes vary considerably from layer to layer. For example, the allowed width and spacing on the lower layers may be four or more times smaller than the allowed widths and spacings on the upper layers. This introduces many additional complications not faced by routers for other applications such as printed circuit board or multi-chip module design. Particular difficulties ensue if the rules are not simple multiples of each other, and when vias must traverse between layers with different rules.\nTypes of routers.\nThe earliest types of EDA routers were \"manual routers\"—the drafter clicked a mouse on the endpoint of each line segment of each net.\nModern PCB design software typically provides \"interactive routers\"—the drafter selects a pad and clicks a few places to give the EDA tool an idea of where to go, and the EDA tool tries to place wires as close to that path as possible without violating design rule checking (DRC). Some more advanced interactive routers have \"push and shove\" (aka \"shove-aside\" or \"automoving\") features in an interactive router; the EDA tool pushes other nets out of the way, if possible, in order to place a new wire where the drafter wants it and still avoid violating DRC.\nModern PCB design software also typically provides \"autorouters\" that route all remaining unrouted connections without human intervention.\nThe main types of autorouters are:\nHow routers work.\nMany routers execute the following overall algorithm:\nFor detailed routing, the most common technique is rip-up and reroute aka rip-up and retry:\nThis process repeats until all nets are routed or the program (or user) gives up.\nAn alternative approach is to treat shorts, design rule violations, obstructions, etc. on a similar footing as excess wire length—that is, as finite costs to be reduced (at first) rather than as absolutes to be avoided. This multi-pass \"iterative-improvement\" routing method is described by the following algorithm:\nMost routers assign wiring layers to carry predominantly \"x\" or \"y\" directional wiring, though there have been routers which avoid or reduce the need for such assignment. There are advantages and disadvantages to each approach. Restricted directions make power supply design and the control of inter-layer crosstalk easier, but allowing arbitrary routes can reduce the need for vias and decrease the number of required wiring layers.", "Engineering,_Manufacturing": 0.9991606474, "qwen": "Yes"}
{"id": "1536973", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1536973", "title": "Electric resistance welding", "text": "Electric resistance welding (ERW) is a welding process where metal parts in contact are permanently joined by heating them with an electric current, melting the metal at the joint. Electric resistance welding is widely used, for example, in manufacture of steel pipe and in assembly of bodies for automobiles. The electric current can be supplied to electrodes that also apply clamping pressure, or may be induced by an external magnetic field. The electric resistance welding process can be further classified by the geometry of the weld and the method of applying pressure to the joint: spot welding, seam welding, flash welding, projection welding, for example. Some factors influencing heat or welding temperatures are the proportions of the workpieces, the metal coating or the lack of coating, the electrode materials, electrode geometry, electrode pressing force, electric current and length of welding time. Small pools of molten metal are formed at the point of most electrical resistance (the connecting or \"faying\" surfaces) as an electric current (100–100,000 A) is passed through the metal. In general, resistance welding methods are efficient and cause little pollution, but their applications are limited to relatively thin materials.\nSpot welding.\nSpot welding is a resistance welding method used to join two or more overlapping metal sheets, studs, projections, electrical wiring hangers, some heat exchanger fins, and some tubing. Usually power sources and welding equipment are sized to the specific thickness and material being welded together. The thickness is limited by the output of the welding power source and thus the equipment range due to the current required for each application. Care is taken to eliminate contaminants between the faying surfaces. Usually, two copper electrodes are simultaneously used to clamp the metal sheets together and to pass current through the sheets. When the current is passed through the electrodes to the sheets, heat is generated due to the higher electrical resistance where the surfaces contact each other. As the electrical resistance of the material causes a heat buildup in the work pieces between the copper electrodes, the rising temperature causes a rising resistance, and results in a molten pool contained most of the time between the electrodes. As the heat dissipates throughout the workpiece in less than a second (resistance welding time is generally programmed as a quantity of AC cycles or milliseconds) the molten or plastic state grows to meet the welding tips. When the current is stopped the copper tips cool the spot weld, causing the metal to solidify under pressure. The water cooled copper electrodes remove the surface heat quickly, accelerating the solidification of the metal, since copper is an excellent conductor. Resistance spot welding typically employs electrical power in the form of direct current, alternating current, medium frequency half-wave direct current, or high-frequency half wave direct current.\nIf excessive heat is applied or applied too quickly, or if the force between the base materials is too low, or the coating is too thick or too conductive, then the molten area may extend to the exterior of the work pieces, escaping the containment force of the electrodes (often up to 30,000 psi). This burst of molten metal is called expulsion, and when this occurs the metal will be thinner and have less strength than a weld with no expulsion. The common method of checking a weld's quality is a peel test. An alternative test is the restrained tensile test, which is much more difficult to perform, and requires calibrated equipment. Because both tests are destructive in nature (resulting in the loss of salable material), non-destructive methods such as ultrasound evaluation are in various states of early adoption by many OEMs.\nThe advantages of the method include efficient energy use, limited workpiece deformation, high production rates, easy automation, and no required filler materials. When high strength in shear is needed, spot welding is used in preference to more costly mechanical fastening, such as riveting. While the shear strength of each weld is high, the fact that the weld spots do not form a continuous seam means that the overall strength is often significantly lower than with other welding methods, limiting the usefulness of the process. It is used extensively in the automotive industry— cars can have several thousand spot welds. A specialized process, called shot welding, can be used to spot weld stainless steel.\nThere are three basic types of resistance welding bonds: solid state, fusion, and reflow braze. In a \"solid state bond\", also called a thermo-compression bond, dissimilar materials with dissimilar grain structure, e.g. molybdenum to tungsten, are joined using a very short heating time, high weld energy, and high force. There is little melting and minimum grain growth, but a definite bond and grain interface. Thus the materials actually bond while still in the solid state. The bonded materials typically exhibit excellent shear and tensile strength, but poor peel strength. In a \"fusion bond\", either similar or dissimilar materials with similar grain structures are heated to the melting point (liquid state) of both. The subsequent cooling and combination of the materials forms a “nugget” alloy of the two materials with larger grain growth. Typically, high weld energies at either short or long weld times, depending on physical characteristics, are used to produce fusion bonds. The bonded materials usually exhibit excellent tensile, peel and shear strengths. In a \"reflow braze bond\", a resistance heating of a low temperature brazing material, such as gold or solder, is used to join either dissimilar materials or widely varied thick/thin material combinations. The brazing material must “wet” to each part and possess a lower melting point than the two workpieces. The resultant bond has definite interfaces with minimum grain growth. Typically the process requires a longer (2 to 100 ms) heating time at low weld energy. The resultant bond exhibits excellent tensile strength, but poor peel and shear strength.\nSeam welding.\nResistance seam welding is a process that produces a weld at the faying surfaces of two similar metals. The seam may be a butt joint or an overlap joint and is usually an automated process. It differs from flash welding in that flash welding typically welds the entire joint at once and seam welding forms the weld progressively, starting at one end. Like spot welding, seam welding relies on two electrodes, usually made from copper, to apply pressure and current. The electrodes are often disc shaped and rotate as the material passes between them. This allows the electrodes to stay in constant contact with the material to make long continuous welds. The electrodes may also move or assist the movement of the material.\nA transformer supplies energy to the weld joint in the form of low voltage, high current AC power. The joint of the work piece has high electrical resistance relative to the rest of the circuit and is heated to its melting point by the current. The semi-molten surfaces are pressed together by the welding pressure that creates a fusion bond, resulting in a uniformly welded structure. Most seam welders use water cooling through the electrode, transformer and controller assemblies due to the heat generated.\nSeam welding produces an extremely durable weld because the joint is forged due to the heat and pressure applied. A properly welded joint formed by resistance welding can easily be stronger than the material from which it is formed.\nA common use of seam welding is during the manufacture of round or rectangular steel tubing. Seam welding has been used to manufacture steel beverage cans but is no longer used for this as modern beverage cans are seamless aluminum.\nThere are two modes for seam welding: Intermittent and continuous. In intermittent seam welding, the wheels advance to the desired position and stop to make each weld. This process continues until the desired length of the weld is reached. In continuous seam welding, the wheels continue to roll as each weld is made.\nLow-frequency electric resistance welding.\nLow-frequency electric resistance welding (LF-ERW) is an obsolete method of welding seams in oil and gas pipelines. It was phased out in the 1970s but as of 2015 some pipelines built with this method remained in service.\nElectric resistance welded (ERW) pipe is manufactured by cold-forming a sheet of steel into a cylindrical shape. Current is then passed between the two edges of the steel to heat the steel to a point at which the edges are forced together to form a bond without the use of welding filler material. Initially this manufacturing process used low frequency AC current to heat the edges. This low frequency process was used from the 1920s until 1970. In 1970, the low frequency process was superseded by a high frequency ERW process which produced a higher quality weld.\nOver time, the welds of low frequency ERW pipe were found to be susceptible to selective seam corrosion, hook cracks, and inadequate bonding of the seams, so low frequency ERW is no longer used to manufacture pipe. The high frequency process is still being used to manufacture pipe for use in new pipeline construction.\nOther methods.\nOther ERW methods include flash welding, resistance projection welding, and upset welding.\nFlash welding is a type of resistance welding that does not use any filler metals. The pieces of metal to be welded are set apart at a predetermined distance based on material thickness, material composition, and desired properties of the finished weld. Current is applied to the metal, and the gap between the two pieces creates resistance and produces the arc required to melt the metal. Once the pieces of metal reach the proper temperature, they are pressed together, effectively forge welding them together.\nProjection welding is a modification of spot welding in which the weld is localized by means of raised sections, or projections, on one or both of the workpieces to be joined. Heat is concentrated at the projections, which permits the welding of heavier sections or the closer spacing of welds. The projections can also serve as a means of positioning the workpieces. Projection welding is often used to weld studs, nuts, and other threaded machine parts to metal plate. It is also frequently used to join crossed wires and bars. This is another high-production process, and multiple projection welds can be arranged by suitable designing and jigging.", "Engineering,_Manufacturing": 0.9999575615, "qwen": "Yes"}
{"id": "41502", "revid": "42522270", "url": "https://en.wikipedia.org/wiki?curid=41502", "title": "Performance measurement period", "text": "In telecommunication, performance measurement period is the period during which performance parameters are measured. \nA performance measurement period is determined by required confidence limits and may vary as a function of the observed parameter values. User time is divided into consecutive performance measurement periods to enable measurement of user information transfer reliability.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "479719", "revid": "1166556203", "url": "https://en.wikipedia.org/wiki?curid=479719", "title": "Applied Materials", "text": "Applied Materials, Inc. is an American corporation that supplies equipment, services and software for the manufacture of semiconductor (integrated circuit) chips for electronics, flat panel displays for computers, smartphones, televisions, and solar products. Integral to the growth of Silicon Valley, the company also supplies equipment to produce coatings for flexible electronics, packaging and other applications. The company is headquartered in Santa Clara, California, and the largest supplier of semiconductor equipment in the world based on revenue. \nHistory.\nFounded in 1967 by Michael A. McNeilly and others, Applied Materials went public in 1972. In subsequent years, the company diversified, until James C. Morgan became CEO in 1976 and returned the company's focus to its core business of semiconductor manufacturing equipment. By 1978, sales increased by 17%.\nIn 1984, Applied Materials became the first U.S. semiconductor equipment manufacturer to open its own technology center in Japan and the first semiconductor equipment company to operate a service center in China. In 1987, Applied introduced a chemical vapor deposition (CVD) machine called the Precision 5000, which differed from existing machines by incorporating diverse processes into a single machine that had multiple process chambers.\nIn 1992, the corporation settled a lawsuit with three former employees for an estimated $600,000. The suit complained that the employees were driven out of the company after complaining about the courses Applied Scholastics had been hired to teach there.\nIn 1993, the Applied Materials' Precision 5000 was inducted into the Smithsonian Institution's permanent collection of Information Age technology.\nIn November 1996, Applied Materials acquired two Israeli companies for an aggregate amount of $285 million. Opal Technologies and Orbot Instruments for $175 million and $110 million in cash, respectively. Orbot produces systems for inspecting patterned silicon wafers for yield enhancement during the semiconductor manufacturing process, as well as systems for inspecting masks used during the patterning process. Opal develops and manufactures high-speed metrology systems used by semiconductor manufacturers to verify critical dimensions during the production of integrated circuits.\nIn 2000, Etec Systems, Inc. was purchased.\nOn June 27, 2001, Applied Materials acquired Israeli company Oramir Semiconductor Equipment Ltd., a supplier of laser cleaning technologies for semiconductor wafers, in a purchase business combination for $21 million in cash.\nIn January 2008, Applied Materials purchased Baccini, an Italian company and designer of tools used in manufacturing solar cells.\nIn 2009, Applied Materials opened its Solar Technology Center, the world's largest commercial solar energy research and development facility, in Xi'an, China.\nApplied Materials' acquisition of Semitool Inc. was completed in December 2009.\nApplied Materials announced its acquisition of Varian Semiconductor in May 2011.\nApplied Materials announced its merger with Tokyo Electron on September 24, 2013. If approved by government regulators, the combined company, to be called Eteris, would be the world's largest supplier of semiconductor processing equipment, with a total market value of $29 billion. However, on April 27, 2015, Applied Materials announced that its merger with Tokyo Electron has been scrapped due to antitrust concerns and fears of dominating the semiconductor equipment industry.\nApplied Materials is named among FORTUNE World's Most Admired Companies in 2018.\nIn 2019, Applied Materials announced its intention to buy semiconductor equipment manufacturer (and former Hitachi group member) Kokusai Electric Corporation from private equity firm KKR for $2.2 billion, but terminated the deal in March 2021 citing delays in getting approval from China's regulator.\nFinances.\nFor the fiscal year 2021, Applied Materials reported earnings of US$5.888 billion, with an annual revenue of US$23.063 billion, a 34% increase over the previous fiscal. Applied Materials market capitalization was valued at over US$36.6 billion in November 2018.\nOrganization.\nApplied is organized into three major business sectors: Semiconductor Products, Applied Global Services, and Display and Adjacent Markets. Applied Materials also operates a venture investing arm called Applied Ventures.\nSemiconductor Products.\nThe company develops and manufactures equipment used in the wafer fabrication steps of creating a semiconductor device, including atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), rapid thermal processing (RTP), chemical mechanical polishing (CMP), etch, ion implantation and wafer inspection. The company acquired Semitool for this group in late 2009. In 2019, Applied Materials agreed to buy semiconductor manufacturer Kokusai for $2.2 Billion.\nApplied Global Services.\nThe Applied Global Services (AGS) group offers equipment installation support and warranty extended support, as well as maintenance support. AGS also offers new and refurbished equipment, as well as upgrades and enhancements for installed base equipment. This sector also includes automation software for manufacturing environments.\nDisplay and Adjacent Markets.\nAGS combined an existing business unit with the display business of Applied Films Corporation, acquired in mid-2006.\nThe manufacturing process for TFT LCDs (thin film transistor liquid crystal displays), commonly employed in computer monitors and televisions, is similar to that employed for integrated circuits. In cleanroom environments both TFT-LCD and integrated circuit production use photolithography, chemical and physical vapor deposition, and testing.\nEnergy and Environmental Solutions (former sector).\nIn 2006, the company acquired Applied Films, a glass coating and web coating business. Also in 2006, Applied announced it was entering the solar manufacturing equipment business. The solar, glass and web businesses were organized into the company's Energy and Environmental Solutions (EES) sector.\nIn 2007, Applied Materials announced the Applied SunFab thin film photovoltaic module production line, with single or tandem junction capability. SunFab applies silicon thin film layers to glass substrate that then produce electricity when exposed to sunlight. In 2009, the company's SunFab line was certified by the International Electrotechnical Commission (IEC). In 2010, Applied announced that it was abandoning the thin film market and closing down their SunFab division. Also in 2007, the company acquired privately held, Switzerland-based HCT Shaping Systems SA, a specialist in wafer sawing tools for both solar and semiconductor wafer manufacture, paying approximately $475 million.\nIn 2008, Applied acquired privately held, Italy-based Baccini SpA for $330M, company that worked in the metallization steps of solar cell manufacturing. The company was listed at the top of VLSI Research's list of supplier of photovoltaic manufacturing equipment for 2008, with sales of $797M.\nSince July 2016 the Energy and Environmental Solutions sector is no longer reported separately. Remaining solar business activities have been included in \"Corporate and Others\".\nFacilities.\nApplied operates in many locations globally, including in Europe, Japan, North America (principally the United States), Israel, China, Italy, India, Korea, Southeast Asia and Taiwan. Applied moved into its Bowers Avenue headquarters in Santa Clara, CA, in 1974.", "Engineering,_Manufacturing": 0.9999985695, "qwen": "Yes"}
{"id": "1446861", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1446861", "title": "Flux-cored arc welding", "text": "Flux-cored arc welding (FCAW or FCA) is a semi-automatic or automatic arc welding process. FCAW requires a continuously-fed consumable tubular electrode containing a flux and a constant-voltage or, less commonly, a constant-current welding power supply. An externally supplied shielding gas is sometimes used, but often the flux itself is relied upon to generate the necessary protection from the atmosphere, producing both gaseous protection and liquid slag protecting the weld.\nTypes.\nOne type of FCAW requires no shielding gas. This is made possible by the flux core in the tubular consumable electrode. However, this core contains more than just flux. It also contains various ingredients that when exposed to the high temperatures of welding generate a shielding gas for protecting the arc. This type of FCAW is attractive because it is portable and generally has good penetration into the base metal. Also, windy conditions need not be considered. Some disadvantages are that this process can produce excessive, noxious smoke (making it difficult to see the weld pool). As with all welding processes, the proper electrode must be chosen to obtain the required mechanical properties. Operator skill is a major factor as improper electrode manipulation or machine setup can cause porosity.\nAnother type of FCAW uses a shielding gas that must be supplied by an external source. This is known informally as \"dual shield\" welding. This type of FCAW was developed primarily for welding structural steels. In fact, since it uses both a flux-cored electrode and an external shielding gas, one might say that it is a combination of gas metal (GMAW) and FCAW. The most often used shielding gases are either straight carbon dioxide or argon carbon dioxide blends. The most common blend used is 75% Argon 25% Carbon Dioxide. This particular style of FCAW is preferable for welding thicker and out-of-position metals. The slag created by the flux is also easy to remove. The main advantages of this process is that in a closed shop environment, it generally produces welds of better and more consistent mechanical properties, with fewer weld defects than either the SMAW or GMAW processes. In practice it also allows a higher production rate, since the operator does not need to stop periodically to fetch a new electrode, as is the case in SMAW. However, like GMAW, it cannot be used in a windy environment as the loss of the shielding gas from air flow will produce porosity in the weld.\nAdvantages and applications.\n\"Used on the following alloys:\"\nDisadvantages.\nOf course, all of the usual issues that occur in welding can occur in FCAW such as incomplete fusion between base metals, slag inclusion (non-metallic inclusions), and cracks in the welds. But there are a few concerns that come up with FCAW that are worth taking special note of:", "Engineering,_Manufacturing": 0.9999819994, "qwen": "Yes"}
{"id": "1446920", "revid": "1170834916", "url": "https://en.wikipedia.org/wiki?curid=1446920", "title": "Friction welding", "text": "Friction welding (FWR) is a solid-state welding and bonding process that generates heat through mechanical friction between workpieces in relative motion to one another. This process is used with the addition of a lateral force called \"upset\" to plastically displace and fuse the materials. No melting occurs, friction welding is not a fusion welding process, but a solid-state welding technique more like forge welding. Friction welding is used with metals and thermoplastics in a wide variety of aviation and automotive applications.\nThe ISO norm of friction welding is EN ISO 15620:2019, which also contains information about the basic terms and definitions and tables of the weldability of metals and alloys.\nHistory.\nSome applications and patents connected with friction welding date back to the turn of the 20th century, and rotary friction welding is the oldest of these methods. W. Richter patented the method of linear friction welding (LFW) process in 1924 in England and 1929 in the Weimar Republic, however, the description of the process was vague and H. Klopstock patented the same process in the Soviet Union in 1924. The first description and experiments related to rotary friction welding took place in the Soviet Union in 1956, when a machinist named A. J. Chdikov researched a myriad of scientific studies and suggested the use of this welding method as a commercial process. The process was introduced to the United States in 1960. The American companies Caterpillar Tractor Company (Caterpillar - CAT), Rockwell International, and American Manufacturing Foundry all developed machines for this process. Patents were also issued throughout Europe and the former Soviet Union. The first studies of friction welding in England were carried out by the Welding Institute in 1961. \nIn the USA, Caterpillar Inc. and MTI, developed an inertia process in 1962. Europe, through KUKA AG and Thompson, launched rotary friction welding for industrial applications in 1966, developed a direct-drive process and in 1974 built the rRS6 double spindle machine for heavy truck axles. Another method was invented in the Soviet Union by one Yu. Klimenko in mid-1960s and patented in 1967, experimentally proven and developed into a commercial technology at The Welding Institute (TWI) in the UK and patented again in 1991: the friction stir welding (FSW) process, a solid-state joining process that uses a non-consumable tool to join two facing workpieces without melting the workpiece material.\nAn improved modification of the standard friction welding technique is Low Force Friction Welding, a hybrid technology developed by EWI and Manufacturing Technology Inc. (MTI), which \"uses an external energy source to raise the interface temperature of the two parts being joined, thereby reducing the process forces required to make a solid-state weld compared to traditional friction welding\". The process applies to both linear and rotary friction welding.\nMetal techniques.\nFriction welding takes many forms but the following are the most popular methods used. \nRotary friction welding.\nRotary friction welding (RFW) is one of the methods of friction welding. One welded element is rotated to the other and pressed down. The heating of the material is caused by friction work and creates a non-separable weld.\nLinear friction welding.\nLinear friction welding (LFW) is the act of moving a single component in a linear reciprocating motion across the face of a stationary competent.\nFriction stir welding.\nFriction stir welding (FSW) is a solid-state joining process that uses a non-consumable tool to join two facing workpieces without melting the workpiece material. Heat is generated by friction between the rotating tool and the workpiece material, which leads to a softened region near the FSW tool. While the tool is traversed along the joint line, it mechanically intermixes the two pieces of metal, and forges the hot and softened metal by the mechanical pressure, which is applied by the tool, much like joining clay, or dough.\nFriction surfacing.\nFriction surfacing is a process derived from friction welding where a coating material is applied to a substrate. A rod composed of the coating material (called a mechtrode) is rotated under pressure, generating a plasticized layer in the rod at the interface with the substrate.\nThermoplastic technique.\nLinear vibration welding.\nIn linear vibration welding the materials are placed in contact and put under pressure. An external vibration force is then applied to slip the pieces relative to each other, perpendicular to the pressure being applied.\nOrbital friction welding.\nOrbital friction welding is similar to spin welding, but uses more complex machine to produce an orbital motion in which the moving part rotates in a small circle, much smaller than the size of the joint as a whole.\nOther information.\nWelds tests for Friction Welding and description of zones.\nQuality requirements of welded joints depend on the form of application, e.g. in the space or flight industry weld errors are not allowed. There are many scientific articles describing the weld, weld quality tests assurance is performed, with measurements and numerical methods. Science tries to gets good quality welds.\nFor example, an ultra fine grain structure of alloy or metal which is obtained by techniques such as severe plastic deformation is desirable, and not changed by the high temperature, a large heat affected zone is unnecessary.\nMoreover, in addition to changing the grain structure during metal joining cycles, by methods where high temperature affected zone was occur, are phase transformations structure. For example, in steel between austenite, ferrite, pearlite, bainite, cementite and martensite, see: . In order to avoid changes solid state welding may be desired and large heat affected zone is not needed if weakens the material properties.\nHeat and mechanical affected zones in friction weld.\nIndividual thermomechanical zones can be described by citing an example article:\nAnthony R.McAndrew, Paul A.Colegrove, Clement Bühr, Bertrand C.D., Flipo Achilleas Vairis, \"A literature review of Ti-6Al-4V linear friction welding\", 2018.\n\"Technically the WCZ and the TMAZ are both \"thermo-mechanically affected zones\" but due to the vastly different microstructures they possess they are often considered separately. The WCZ experiences significant dynamic recrystallisation (DRX), the TMAZ does not. The material in HAZ is not deformed mechanically but is affected by the heat. The region from one TMAZ/HAZ boundary to the other is often referred to as the \"TMAZ thickness\" or the plastically affected zone (PAZ). For the remainder of this article this region will be referred to as the PAZ.\"\nZones:\nSimilar terms exist in welding.\nSeizure resistance.\nFriction welding may unintentionally occur at sliding surfaces like bearings. This happens in particular if the lubricating oil film between sliding surfaces becomes thinner than the surface roughness, which may be due to low speed, low temperature, oil starvation, excessive clearance, low viscosity of the oil, high roughness of the surfaces, or a combination thereof.\nThe seizure resistance is the ability of a material to resist friction welding. It is a fundamental property of bearing surfaces and in general of sliding surfaces under load.\nTerms and definitions, name shortcuts.\nTo quote ISO (the International Organization for Standardization) - ISO 15620:2019(en) Welding — Friction welding of metallic materials:\n\"axial force - force in axial direction between components to be welded,\nburn-off length - loss of length during the friction phase,\nburn-off rate - rate of shortening of the components during the friction welding process,\ncomponent - single item before welding,\ncomponent induced braking - reduction in rotational speed resulting from friction between the interfaces,\nexternal braking - braking located externally reducing the rotational speed,\nfaying surface - surface of one component that is to be in contact with a surface of another component to form a joint,\nforge force - force applied normal to the faying surfaces at the time when relative movement between the components is ceasing or has ceased,\nforge burn-off length - amount by which the overall length of the components is reduced during the application of the forge force,\nforge phase - interval time in the friction welding cycle between the start and finish of application of the forge force,\nforge pressure - pressure (force per unit area) on the faying surfaces resulting from the axial forge force,\nforge time - time for which the forge force is applied to the components,\nfriction force - force applied perpendicularly to the faying surfaces during the time that there is relative movement between the components,\nfriction phase - interval time in the friction welding cycle in which the heat necessary for making a weld is generated by relative motion and the friction forces between the components i.e. from contact of components to the start of deceleration,\nfriction pressure - pressure (force per unit area) on the faying surfaces resulting from the axial friction force,\nfriction time - time during which relative movement between the components takes place at rotational speed and under application of the friction forces,\ninterface - contact area developed between the faying surfaces after completion of the welding operation,\nrotational speed - number of revolutions per minute of rotating component,\nstick-out - distance a component sticks out from the fixture, or chuck in the direction of the mating component,\ndeceleration phase - interval in the friction welding cycle in which the relative motion of the components is decelerated to zero,\ndeceleration time - time required by the moving component to decelerate from friction speed to zero speed,\ntotal length loss (upset) - loss of length that occurs as a result of friction welding, i.e. the sum of the burn-off length and the forge burn-off length,\ntotal weld time - time elapsed between component contact and end of forging phase,\nwelding cycle - succession of operations carried out by the machine to make a weldment and return to the initial position, excluding component - handling operations,\nweldment - two or more components joined by welding.\"", "Engineering,_Manufacturing": 1.000005722, "qwen": "Yes"}
{"id": "1448500", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=1448500", "title": "Laser beam welding", "text": "Laser beam welding (LBW) is a welding technique used to join pieces of metal or thermoplastics through the use of a laser. The beam provides a concentrated heat source, allowing for narrow, deep welds and high welding rates. The process is frequently used in high volume and precision requiring applications using automation, as in the automotive and aeronautics industries. It is based on keyhole or penetration mode welding.\nOperation.\nLike electron-beam welding (EBW), laser beam welding has high power density (on the order of 1 MW/cm2) resulting in small heat-affected zones and high heating and cooling rates. The spot size of the laser can vary between 0.2 mm and 13 mm, though only smaller sizes are used for welding. The depth of penetration is proportional to the amount of power supplied, but is also dependent on the location of the focal point: penetration is maximized when the focal point is slightly below the surface of the workpiece\nA continuous or pulsed laser beam may be used depending upon the application. Millisecond-long pulses are used to weld thin materials such as razor blades while continuous laser systems are employed for deep welds.\nLBW is a versatile process, capable of welding carbon steels, HSLA steels, stainless steel, aluminum, and titanium. Due to high cooling rates, cracking is a concern when welding high-carbon steels. The weld quality is high, similar to that of electron beam welding. The speed of welding is proportional to the amount of power supplied but also depends on the type and thickness of the workpieces. The high power capability of gas lasers make them especially suitable for high volume applications. LBW is particularly dominant in the automotive industry.\nSome of the advantages of LBW in comparison to EBW are:\nA derivative of LBW, laser-hybrid welding, combines the laser of LBW with an arc welding method such as gas metal arc welding. This combination allows for greater positioning flexibility, since GMAW supplies molten metal to fill the joint, and due to the use of a laser, increases the welding speed over what is normally possible with GMAW. Weld quality tends to be higher as well, since the potential for undercutting is reduced.\nEquipment.\nAutomation and CAM.\nAlthough laser beam welding can be accomplished by hand, most systems are automated and use a system of computer aided manufacturing based on computer aided designs. Laser welding can also be coupled with milling to form a finished part.\nIn 2016 the RepRap project, which historically worked on fused filament fabrication, expanded to development of open source laser welding systems. Such systems have been fully characterized and can be used in a wide scale of applications while reducing conventional manufacturing costs.\nLasers.\nSolid state.\nSolid-state lasers operate at wavelengths on the order of 1 micrometer, much shorter than gas lasers used for welding, and as a result require that operators wear special eyewear or use special screens to prevent retina damage. Nd:YAG lasers can operate in both pulsed and continuous mode, but the other types are limited to pulsed mode. \nThe original and still popular solid-state design is a single crystal shaped as a rod approximately 20 mm in diameter and 200 mm long, and the ends are ground flat. This rod is surrounded by a flash tube containing xenon or krypton. \nWhen flashed, a pulse of light lasting about two milliseconds is emitted by the laser. Disk shaped crystals are growing in popularity in the industry, and flashlamps are giving way to diodes due to their high efficiency. \nTypical power output for ruby lasers is 10–20 W, while the Nd:YAG laser outputs between 0.04–6,000 W. To deliver the laser beam to the weld area, fiber optics are usually employed.\nGas.\nGas lasers use high-voltage, low-current power sources to supply the energy needed to excite the gas mixture used as a lasing medium. \nThese lasers can operate in both continuous and pulsed mode, and the wavelength of the gas laser beam is 10.6 μm, deep infrared, i.e. 'heat'. \nFiber optic cable absorbs and is destroyed by this wavelength, so a rigid lens and mirror delivery system is used. \nPower outputs for gas lasers can be much higher than solid-state lasers, reaching 25 kW.\nFiber.\nIn fiber lasers, the main medium is the optical fiber itself. They are capable of power up to 50 kW and are increasingly being used for robotic industrial welding.\nLaser beam delivery.\nModern laser beam welding machines can be grouped into two types. In the traditional type, the laser output is moved to follow the seam. This is usually achieved with a robot. In many modern applications, remote laser beam welding is used. In this method, the laser beam is moved along the seam with the help of a laser scanner, so that the robotic arm does not need to follow the seam any more. The advantages of remote laser welding are the higher speed and the higher precision of the welding process.\nThermal modeling of pulsed-laser welding.\nPulsed-laser welding has advantages over continuous wave (CW) laser welding. Some of these advantages are lower porosity and less spatter. Pulsed-laser welding also has some disadvantages such as causing hot cracking in aluminum alloys. Thermal analysis of the pulsed-laser welding process can assist in prediction of welding parameters such as depth of fusion, cooling rates, and residual stresses. Due to the complexity of the pulsed laser process, it is necessary to employ a procedure that involves a development cycle. The cycle involves constructing a mathematical model, calculating a thermal cycle using numerical modeling techniques like either finite elemental modeling (FEM) or finite difference method (FDM) or analytical models with simplifying assumptions, and validating the model by experimental measurements.\nA methodology combining some of the published models involves:\nStep 1.\nNot all radiant energy is absorbed and turned into heat for welding. Some of the radiant energy is absorbed in the plasma created by vaporizing and then subsequently ionizing the gas. In addition, the absorptivity is affected by the wavelength of the beam, the surface composition of the material being welded, the angle of incidence, and the temperature of the material.\nRosenthal point source assumption leaves an infinitely high temperature discontinuity which is addressed by assuming a Gaussian distribution instead. Radiant energy is also not uniformly distributed within the beam. Some devices produce Gaussian energy distributions, whereas others can be bimodal. A Gaussian energy distribution can be applied by multiplying the power density by a function like this:formula_1, where r is the radial distance from the center of the beam, formula_2=beam radius or spot size.\nUsing a temperature distribution instead of a point source assumption allows for easier calculation of temperature-dependent material properties such as absorptivity. On the irradiated surface, when a keyhole is formed, Fresnel reflection (the almost complete absorption of the beam energy due to multiple reflection within the keyhole cavity) occurs and can be modeled by formula_3, where ε is a function of dielectric constant, electric conductivity, and laser frequency. θ is the angle of incidence. Understanding the absorption efficiency is key to calculating thermal effects.\nStep 2.\nLasers can weld in one of two modes: conduction and keyhole. Which mode is in operation depends on whether the power density is sufficiently high enough to cause evaporation. Conduction mode occurs below the vaporization point while keyhole mode occurs above the vaporization point. The keyhole is analogous to an air pocket. The air pocket is in a state of flux. Forces such as the recoil pressure of the evaporated metal open the keyhole while gravity (aka hydrostatic forces) and metal surface tension tend to collapse it. At even higher power densities, the vapor can be ionized to form a plasma.\nThe recoil pressure is determined by using the Clausius-Clapeyron equation.formula_4, where P is the equilibrium vapor pressure, T is the liquid surface temperature, HLV is the latent heat of vaporization, TLV is the equilibrium temperature at the liquid-vapor interface. Using the assumption that the vapor flow is limited to sonic velocities, one gets that formula_5, where Po is atmospheric pressure and Pr is recoil pressure.\nStep 3.\nThis pertains to keyhole profiles. Fluid flow velocities are determined by\nformula_6\nformula_7\nformula_8\nwhere formula_9 is the velocity vector, P=pressure, ρ= mass density, formula_10=viscosity, β=thermal expansion coefficient, g=gravity, and F is the volume fraction of fluid in a simulation grid cell.\nStep 4.\nIn order to determine the boundary temperature at the laser impingement surface, you'd apply an equation like this. formula_11, where kn=the thermal conductivity normal to the surface impinged on by the laser, h=convective heat transfer coefficient for air, σ is the Stefan–Boltzmann constant for radiation, and ε is the emissivity of the material being welded on, q is laser beam heat flux.\nUnlike CW (Continuous Wave) laser welding which involves one moving thermal cycle, pulsed laser involves repetitively impinging on the same spot, thus creating multiple overlapping thermal cycles. A method of addressing this is to add a step function that multiplies the heat flux by one when the beam is on but multiplies the heat flux by zero when the beam is off. One way to achieve this is by using a Kronecker delta which modifies q as follows: formula_12, where δ= the Kronecker delta, qe=experimentally determined heat flux. The problem with this method, is it does not allow you to see the effect of pulse duration. One way of solving this is to a use a modifier that is time-dependent function such as:\nformula_13\nwhere v= pulse frequency, n=0,1, 2...,v-1), τ= pulse duration.\nNext, you would apply this boundary condition and solve for Fourier's 2nd Law to obtain the internal temperature distribution. Assuming no internal heat generation, the solution is formula_14, where k=thermal conductivity, ρ=density, Cp=specific heat capacity, formula_9=fluid velocity vector.\nStep 5.\nIncrementing is done by discretizing the governing equations presented in the previous steps and applying the next time and length steps.\nStep 6.\nResults can be validated by specific experimental observations or trends from generic experiments. These experiments have involved metallographic verification of the depth of fusion.\nConsequences of simplifying assumptions.\nThe physics of pulsed laser can be very complex and therefore, some simplifying assumptions need to be made to either speed up calculation or compensate for a lack of materials properties. The temperature-dependence of material properties such as specific heat are ignored to minimize computing time.\nThe liquid temperature can be overestimated if the amount of heat loss due to mass loss from vapor leaving the liquid-metal interface is not accounted for.", "Engineering,_Manufacturing": 1.0000061989, "qwen": "Yes"}
{"id": "8239195", "revid": "18413898", "url": "https://en.wikipedia.org/wiki?curid=8239195", "title": "TO-3", "text": "In electronics, TO-3 is a designation for a standardized metal semiconductor package used for power semiconductors, including transistors, silicon controlled rectifiers, and, integrated circuits. \"TO\" stands for \"Transistor Outline\" and relates to a series of technical drawings produced by JEDEC.\nThe TO-3 case has a flat surface which can be attached to a heatsink, normally via a thermally conductive but electrically insulating washer. The design originated at Motorola around 1955 from a group headed by Dr. Virgil E. Bottom. who was director of research of the Motorola Semiconductor Division. The first use of this design was for the germanium alloy-junction power transistor 2N176 – the first power transistor to be put into quantity production. The lead spacing was originally intended to allow plugging the device into a then-common tube socket.\nTypical applications.\nThe metal package can be attached to a heat sink, making it suitable for devices dissipating several watts of heat. Thermal compound is used to improve heat transfer between the device case and the heat sink. Since the device case is one of the electrical connections, an insulator may be required to electrically isolate the component from the heatsink. Insulating washers may be made of mica or other materials with good thermal conductivity.\nThe case is used with high-power and high-current devices, on the order of a few tens of amperes current and up to a hundred watts of heat dissipation. The case surfaces are metal for good heat conductivity and durability. The metal-to-metal and metal-to-glass joints provide hermetic seals that protect the semiconductor from liquids and gases.\nCompared with equivalent plastic packages, the TO-3 is more costly. The spacing and dimensions of the case leads make it unsuitable for higher frequency (radio frequency) devices.\nConstruction.\nThe semiconductor die component is mounted on a raised platform on a metal plate, with the metal can welded on top of it; providing high heat conductivity and durability. The metal case is connected to the internal device and the leads are connected to the die with bonding wires.\nThe TO-3 package consists of a diamond-shaped base plate with diagonals of and . The plate has two mounting holes on the long diagonal, with the centers spaced apart. The cap attached to one side of the plate brings the total height to up to . Two pins on the other side of the plate are isolated from the package by individual glass-metal seals. The metal case forms the third connection (in the case of a bipolar junction transistor this is typically the collector).\nVariants.\nTO-3 package variants for integrated circuits can have more than two leads. The height of the cap and the thickness of the leads differs between variants of the TO-3 package.\nTO-41.\nThe two pins of the TO-41 package end in soldering pads with holes in them to make it easier to solder wires to the pins for point-to-point construction (as opposed to soldering a TO-3 package on a printed circuit board). Otherwise the TO-41 package has the same dimensions as the TO-3 package. Some variants of the TO-41 package have a third pin with a soldering pad connected to the case (e.g. AD133, AUY21). This 3-pin package was standardized by IEC as C14B/B28.\nTO-204.\nTO-204 is intended to replace previous definitions of flange-mounted packages with a pin spacing. The different outlines are now defined as variants of TO-204: TO-3 is renamed to TO-204-AA, TO-41 to TO-204-AB. A new package with a reduced maximum height of is added as TO-204-AC. Two additional variants specify pins thicker than the original to allow higher currents: for TO-204-AD and for TO-204-AE.\nCommon components in a TO-3 package.\nCommon voltage regulator integrated circuits:\nCommon transistors:", "Engineering,_Manufacturing": 0.9999417067, "qwen": "Yes"}
{"id": "3058053", "revid": "44120587", "url": "https://en.wikipedia.org/wiki?curid=3058053", "title": "Electronics manufacturing services", "text": "Electronics Manufacturing Services (EMS) is a term used for companies that design, manufacture, test, distribute, and provide return/repair services for electronic components and assemblies for original equipment manufacturers (OEMs). The concept is also referred to as Electronics Contract Manufacturing (ECM).\nMany consumer electronics are built in China, due to maintenance cost, availability of materials, and speed as opposed to other countries such as the United States. Cities such as Shenzhen and Penang have become important production centres for the industry, attracting many consumer electronics companies such as Apple Inc. Some companies such as Flex and Wistron are Original design manufacturers and providers of Electronics manufacturing services.\nHistory.\nThe EMS industry was initially established in 1961 by SCI Systems of Huntsville Alabama. The industry realized its most significant growth in the 1980s; at the time, most electronics manufacturing for large-scale product runs was handled by the OEMs in-house assembly. These new companies offered flexibility and eased human resources issues for smaller companies doing limited runs. The business model for the EMS industry is to specialize in large economies of scale in manufacturing, raw materials procurement and pooling together resources, industrial design expertise as well as create added value services such as warranty and repairs. This frees up the customer who does not need to manufacture and keep huge inventories of products. Therefore, they can respond to sudden spikes in demand more quickly and efficiently.\nThe development of Surface Mount Technology (SMT) on printed circuit boards (PCB) allowed for the rapid assembly of electronics. By the mid-1990s the advantages of the EMS concept became compelling and OEMs began outsourcing PCB assembly (PCBA) in large scale. By the end of the 1990s and early 2000s, many OEMs sold their assembly plants to EMSs, aggressively vying for market share. A wave of consolidation followed as the more cash-flush EMS firms were able to buy up quickly both existing plants as well as smaller EMS companies.\nMarket segments.\nThe EMS industry is commonly divided into Tiers by their revenue:\nThere is no hard rule on the actual revenue designation at this time. \nOther categories have been suggested by StepBeyond/EMSinsider and CIRCUITS ASSEMBLY: Micro Tier (<$50M); Tier 4 <10m and \"Tier Mega\" referring to the Big 2, Foxconn and Flex.\nAnother distinction is drawn between EMS that specializes in High Mix Low Volume (HMLV) and High Volume Low Mix (HVLM). Mix refers generally to the complexity or different models of the PCB assembly. Volume refers to the number of units built, with products like consumer electronics on the high end and prototype, medical electronics or machinery on the low end. Typically, lower Tier EMS provide HMLV and higher Tier provide HVLM.\nDuring technology's late-1990s heyday, EMS players routinely acquired assets in high-cost locations. EMS players largely focused on printed circuit board fabrication, leaving system assembly to the OEMs. EMS companies largely disdained industries outside the world of information processing (computers) and communications. In recent years, EMS players have shifted production to low-cost geographies; embraced non-traditional industries including consumer electronics, industrial, medical and instrumentation; and added substantial vertical capabilities, stretching from design and ODM through system assembly, test, delivery and logistics, warranty and repair, network services, software and silicon design, and customer service.\nEMS has also started to provide design services used in conceptual product development advice and mechanical, electrical and software design assistance. Testing services perform in-circuit, functional, environmental, agency compliance, and analytical laboratory testing. Electronics manufacturing services are located throughout the world and provide numerous benefits. They vary in terms of production capabilities and comply with various quality standards and regulatory requirements.\nNotable companies.\nCompanies engaged in High Volume Low Mix (HVLM) production:\nCompanies engaged in Medium Mix Medium Volume (MMMV) production:\nCompanies engaged in High Mix Medium Volume (HMMV) production:\nE2MS.\nE2MS (Electronic Engineering Manufacturing Service) refers to the strategy of integrating product development, prototyping and industrialization services into a traditional EMS business, with the aim to harness potential synergies. A typical E2MS offering will start in the design phase, then continue to support the client in development, prototyping, tooling and production all the way to the testing phase, allowing for faster ramp-up as the product is prepared for mass-production up-front.\nThe term E2MS was first coined by Escatec and has since been adopted by numerous Tier 2 and Tier 3 producers. Larger companies (Tier 1) have gone even further and offered full concept to mass-production and often taking a stake in the intellectual property, becoming more similar to ODM companies.", "Engineering,_Manufacturing": 0.999910593, "qwen": "Yes"}
{"id": "3060044", "revid": "20183", "url": "https://en.wikipedia.org/wiki?curid=3060044", "title": "Process design", "text": "In chemical engineering, process design is the choice and sequencing of units for desired physical and/or chemical transformation of materials. Process design is central to chemical engineering, and it can be considered to be the summit of that field, bringing together all of the field's components.\nProcess design can be the design of new facilities or it can be the modification or expansion of existing facilities. The design starts at a conceptual level and ultimately ends in the form of fabrication and construction plans.\nProcess design is distinct from equipment design, which is closer in spirit to the design of unit operations. Processes often include many unit operations.\nDocumentation.\nProcess design documents serve to define the design and they ensure that the design components fit together. They are useful in communicating ideas and plans to other engineers involved with the design, to external regulatory agencies, to equipment vendors and to construction contractors.\nIn order of increasing detail, process design documents include:\nProcess designers typically write operating manuals on how to start-up, operate and shut-down the process. They often also develop accident plans and projections of process operation on the environment.\nDocuments are maintained after construction of the process facility for the operating personnel to refer to. The documents also are useful when modifications to the facility are planned.\nA primary method of developing the process documents is process flowsheeting.\nDesign considerations.\nThere are several considerations that need to be made when designing any chemical process unit. Design conceptualization and considerations can begin once product purities, yields, and throughput rates are all defined.\nObjectives that a design may strive to include:\nConstraints include:\nOther factors that designers may include are:\nSources of design information.\nDesigners usually do not start from scratch, especially for complex projects. Often the engineers have pilot plant data available or data from full-scale operating facilities. Other sources of information include proprietary design criteria provided by process licensors, published scientific data, laboratory experiments, and suppliers of feedstocks and utilities.\nDesign process.\nDesign starts with process synthesis - the choice of technology and combinations of industrial units to achieve goals. More detailed design proceeds as other engineers and stakeholders sign off on each stage: conceptual to detailed design.\nSimulation software is often used by design engineers. Simulations can identify weaknesses in designs and allow engineers to choose better alternatives. However, engineers still rely on heuristics, intuition, and experience when designing a process. Human creativity is an element in complex designs.", "Engineering,_Manufacturing": 0.9998636246, "qwen": "Yes"}
{"id": "3064522", "revid": "1140901070", "url": "https://en.wikipedia.org/wiki?curid=3064522", "title": "Predictive maintenance", "text": "Predictive maintenance techniques are designed to help determine the condition of in-service equipment in order to estimate when maintenance should be performed. This approach promises cost savings over routine or time-based preventive maintenance, because tasks are performed only when warranted. Thus, it is regarded as condition-based maintenance carried out as suggested by estimations of the degradation state of an item.\nThe main promise of predictive maintenance is to allow convenient scheduling of corrective maintenance, and to prevent unexpected equipment failures. The key is \"the right infor equipment lifetime, increased plant safety, fewer accidents with negative impact on environment, and optimized spare parts handling.\nPredictive maintenance differs from preventive maintenance because it relies on the actual condition of equipment, rather than average or expected life statistics, to predict when maintenance will be required. Typically, Machine Learning approaches are adopted for the definition of the actual condition of the system and for forecasting its future states.\nSome of the main components that are necessary for implementing predictive maintenance are data collection and preprocessing, early fault detection, fault detection, time to failure prediction, maintenance scheduling and resource optimization. Predictive maintenance has also been considered to be one of the driving forces for improving productivity and one of the ways to achieve \"just-in-time\" in manufacturing.\nOverview.\nPredictive maintenance evaluates the condition of equipment by performing periodic (offline) or continuous (online) equipment condition monitoring. The ultimate goal of the approach is to perform maintenance at a scheduled point in time when the maintenance activity is most cost-effective and before the equipment loses performance within a threshold. This results in a reduction in unplanned downtime costs because of failure, where costs can be in the hundreds of thousands per day depending on industry. In energy production, in addition to loss of revenue and component costs, fines can be levied for non-delivery, increasing costs even further. This is in contrast to time- and/or operation count-based maintenance, where a piece of equipment gets maintained whether it needs it or not. Time-based maintenance is labor intensive, ineffective in identifying problems that develop between scheduled inspections, and therefore is not cost-effective.\nThe \"predictive\" component of predictive maintenance stems from the goal of predicting the future trend of the equipment's condition. This approach uses principles of statistical process control to determine at what point in the future maintenance activities will be appropriate.\nMost predictive inspections are performed while equipment is in service, thereby minimizing disruption of normal system operations. Adoption of predictive maintenance can result in substantial cost savings and higher system reliability.\nReliability-centered maintenance emphasizes the use of predictive maintenance techniques in addition to traditional preventive measures. When properly implemented, it provides companies with a tool for achieving lowest asset net present costs for a given level of performance and risk.\nOne goal is to transfer the predictive maintenance data to a computerized maintenance management system so that the equipment condition data is sent to the right equipment object to trigger maintenance planning, work order execution, and reporting. Unless this is achieved, the predictive maintenance solution is of limited value, at least if the solution is implemented on a medium to large size plant with tens of thousands pieces of equipment. In 2010, the mining company Boliden, implemented a combined Distributed Control System and predictive maintenance solution integrated with the plant computerized maintenance management system on an object to object level, transferring equipment data using protocols like Highway Addressable Remote Transducer Protocol, IEC61850 and OLE for process control.\nTechnologies.\nTo evaluate equipment condition, predictive maintenance utilizes nondestructive testing technologies such as infrared, acoustic (partial discharge and airborne ultrasonic), corona detection, vibration analysis, sound level measurements, oil analysis, and other specific online tests. A new approach in this area is to utilize measurements on the actual equipment in combination with measurement of process performance, measured by other devices, to trigger equipment maintenance. This is primarily available in collaborative process automation systems (CPAS). Site measurements are often supported by wireless sensor networks to reduce the wiring cost.\nVibration analysis is most productive on high-speed rotating equipment and can be the most expensive component of a PdM program to get up and running. Vibration analysis, when properly done, allows the user to evaluate the condition of equipment and avoid failures. The latest generation of vibration analyzers comprises more capabilities and automated functions than its predecessors. Many units display the full vibration spectrum of three axes simultaneously, providing a snapshot of what is going on with a particular machine. But despite such capabilities, not even the most sophisticated equipment successfully predicts developing problems unless the operator understands and applies the basics of vibration analysis.\nIn certain situations, strong background noise interferences from several competing sources may mask the signal of interest and hinder the industrial applicability of vibration sensors. Consequently, motor current signature analysis (MCSA) is a non-intrusive alternative to vibration measurement which has the potential to monitor faults from both electrical and mechanical systems.\nRemote visual inspection is the first non-destructive testing. It provides a cost-efficient primary assessment. Essential information and defaults can be deduced from the external appearance of the piece, such as folds, breaks, cracks, and corrosion. The remote visual inspection has to be carried out in good conditions with a sufficient lighting (350 LUX at least). When the part of the piece to be controlled is not directly accessible, an instrument made of mirrors and lenses called endoscope is used. Hidden defects with external irregularities may indicate a more serious defect inside.\nAcoustical analysis can be done on a sonic or ultrasonic level. New ultrasonic techniques for condition monitoring make it possible to \"hear\" friction and stress in rotating machinery, which can predict deterioration earlier than conventional techniques. Ultrasonic technology is sensitive to high-frequency sounds that are inaudible to the human ear and distinguishes them from lower-frequency sounds and mechanical vibration. Machine friction and stress waves produce distinctive sounds in the upper ultrasonic range.\nChanges in these friction and stress waves can suggest deteriorating conditions much earlier than technologies such as vibration or oil analysis. With proper ultrasonic measurement and analysis, it's possible to differentiate normal wear from abnormal wear, physical damage, imbalance conditions, and lubrication problems based on a direct relationship between asset and operating conditions.\nSonic monitoring equipment is less expensive, but it also has fewer uses than ultrasonic technologies. Sonic technology is useful only on mechanical equipment, while ultrasonic equipment can detect electrical problems and is more flexible and reliable in detecting mechanical problems.\nInfrared monitoring and analysis has the widest range of application (from high- to low-speed equipment), and it can be effective for spotting both mechanical and electrical failures; some consider it to currently be the most cost-effective technology. \nOil analysis is a long-term program that, where relevant, can eventually be more predictive than any of the other technologies. It can take years for a plant's oil program to reach this level of sophistication and effectiveness. \nAnalytical techniques performed on oil samples can be classified in two categories: used oil analysis and wear particle analysis. Used oil analysis determines the condition of the lubricant itself, determines the quality of the lubricant, and checks its suitability for continued use. Wear particle analysis determines the mechanical condition of machine components that are lubricated. Through wear particle analysis, you can identify the composition of the solid material present and evaluate particle type, size, concentration, distribution, and morphology.\nThe use of Model Based Condition Monitoring for predictive maintenance programs is becoming increasingly popular over time. This method involves spectral analysis on the motor's current and voltage signals and then compares the measured parameters to a known and learned model of the motor to diagnose various electrical and mechanical anomalies. This process of \"model based\" condition monitoring was originally designed and used on NASA's space shuttle to monitor and detect developing faults in the space shuttle's main engine. It allows for the automation of data collection and analysis tasks, providing round the clock condition monitoring and warnings about faults as they develop. Other predictive maintenance methods are related to smart testing strategies.", "Engineering,_Manufacturing": 0.9999029636, "qwen": "Yes"}
{"id": "3064915", "revid": "44690822", "url": "https://en.wikipedia.org/wiki?curid=3064915", "title": "Boring (manufacturing)", "text": "In machining, boring is the process of enlarging a hole that has already been drilled (or cast) by means of a single-point cutting tool (or of a boring head containing several such tools), such as in boring a gun barrel or an engine cylinder. Boring is used to achieve greater accuracy of the diameter of a hole, and can be used to cut a tapered hole. Boring can be viewed as the internal-diameter counterpart to turning, which cuts external diameters. \nThere are various types of boring. The boring bar may be supported on both ends (which only works if the existing hole is a through hole), or it may be supported at one end (which works for both, through holes and blind holes). Lineboring (line boring, line-boring) implies the former. Backboring (back boring, back-boring) is the process of reaching through an existing hole and then boring on the \"back\" side of the workpiece (relative to the machine headstock). \nBecause of the limitations on tooling design imposed by the fact that the workpiece mostly surrounds the tool, boring is inherently somewhat more challenging than turning, in terms of decreased toolholding rigidity, increased clearance angle requirements (limiting the amount of support that can be given to the cutting edge), and difficulty of inspection of the resulting surface (size, form, surface roughness). These are the reasons why boring is viewed as an area of machining practice in its own right, separate from turning, with its own tips, tricks, challenges, and body of expertise, despite the fact that they are in some ways identical. \nThe first boring machine tool was invented by John Wilkinson in 1775.\nBoring and turning have abrasive counterparts in internal and external cylindrical grinding. Each process is chosen based on the requirements and parameter values of a particular application.\nMachine tools used.\nThe boring process can be executed on various machine tools, including (1) general-purpose or universal machines, such as lathes (/turning centers) or milling machines (/machining centers), and (2) machines designed to specialize in boring as a primary function, such as jig borers and boring machines or boring mills, which include vertical boring mills (workpiece rotates around a vertical axis while boring bar/head moves linearly; essentially a vertical lathe) and horizontal boring mills (workpiece sits on a table while the boring bar rotates around a horizontal axis; essentially a specialized horizontal milling machine).\nBoring mills and milling machines.\nThe dimensions between the piece and the tool bit can be changed about two axes to cut both vertically and horizontally into the internal surface. The cutting tool is usually single point, made of M2 and M3 high-speed steel or P10 and P01 carbide. A tapered hole can also be made by swiveling the head. \nBoring machines come in a large variety of sizes and styles. Boring operations on small workpieces can be carried out on a lathe while larger workpieces are machined on boring mills. Workpieces are commonly in diameter, but can be as large as . Power requirements can be as much as . Cooling of the bores is done through a hollow passageway through the boring bar where coolant can flow freely. Tungsten-alloy disks are sealed in the bar to counteract vibration and chatter during boring. The control systems can be computer-based, allowing for automation and increased consistency.\nBecause boring is meant to decrease the product tolerances on pre-existing holes, several design considerations apply. First, large length-to-bore-diameters are not preferred due to cutting tool deflection. Next, through holes are preferred over blind holes (holes that do not traverse the thickness of the work piece). Interrupted internal working surfaces—where the cutting tool and surface have discontinuous contact—are preferably avoided. The boring bar is the protruding arm of the machine that holds the cutting tool(s), and must be very rigid. \nBecause of the factors just mentioned, deep-hole drilling and deep-hole boring are inherently challenging areas of practice that demand special tooling and techniques. Nevertheless, technologies have been developed that produce deep holes with impressive accuracy. In most cases they involve multiple cutting points, diametrically opposed, whose deflection forces cancel each other out. They also usually involve delivery of cutting fluid pumped under pressure through the tool to orifices near the cutting edges. Gun drilling and cannon boring are classic examples. First developed to make the barrels of firearms and artillery, these machining techniques find wide use today for manufacturing in many industries. \nVarious fixed cycles for boring are available in CNC controls. These are preprogrammed subroutines that move the tool through successive passes of cut, retract, advance, cut again, retract again, return to the initial position, and so on. These are called using G-codes such as G76, G85, G86, G87, G88, G89; and also by other less common codes specific to particular control builders or machine tool builders.\nLathes.\nLathe boring is a cutting operation that uses a single-point cutting tool or a boring head to produce conical or cylindrical surfaces by enlarging an existing opening in a workpiece. For nontapered holes, the cutting tool moves parallel to the axis of rotation. For tapered holes, the cutting tool moves at an angle to the axis of rotation. Geometries ranging from simple to extremely complex in a variety of diameters can be produced using boring applications. Boring is one of the most basic lathe operations next to turning and drilling. \nLathe boring usually requires that the workpiece be held in the chuck and rotated. As the workpiece is rotated, a boring bar with an insert attached to the tip of the bar is fed into an existing hole. When the cutting tool engages the workpiece, a chip is formed. Depending on the type of tool used, the material, and the feed rate, the chip may be continuous or segmented. The surface produced is called a bore.\nThe geometry produced by lathe boring is usually of two types: straight holes and tapered holes. Several diameters can also be added to each shape hole if required. To produce a taper, the tool may be fed at an angle to the axis of rotation or both feed and axial motions may be concurrent. Straight holes and counterbores are produced by moving the tool parallel to the axis of workpiece rotation.\nThe four most commonly used workholding devices are the three-jaw chuck, the four-jaw chuck, the collet, and the faceplate. The three-jaw chuck is used to hold round or hex workpieces because the work is automatically centered. On these chucks the runout faces limitations; on late-model CNCs, it can be quite low if all conditions are excellent, but traditionally it is usually at least .001-.003 in (0.025-0.075 mm). The four-jaw chuck is used either to hold irregular shapes or to hold round or hex to extremely low runout (with time spent indicating and clamping each piece), in both cases because of its independent action on each jaw. The face plate is also used for irregular shapes. Collets combine self-centering chucking with low runout, but they involve higher costs.\nLimitations.\nFor most lathe boring applications, tolerances greater than ±0.010 in (±0.25 mm) are easily held. Tolerances from there down to ±0.005 in (±0.13 mm) are usually held without especial difficulty or expense, even in deep holes. Tolerances between ±0.004 in (±0.10 mm) and ±0.001 in (±0.025 mm) are where the challenge begins rising. In deep holes with tolerances this tight, the limiting factor is just as often the geometric constraint as the size constraint. In other words, it may be easy to hold the diameter within .002\" at any diametrical measurement point, but difficult to hold the cylindricity of the hole to within a zone delimited by the .002\" constraint, across more than 5 diameters of hole depth (depth measured in terms of diameter:depth aspect ratio). For highest-precision applications, tolerances can generally be held within ±0.0005 in (±0.013 mm) only for shallow holes. In some cases tolerances as tight as ±0.0001 in (±0.0038 mm) can be held in shallow holes, but it is expensive, with 100% inspection and loss of nonconforming parts adding to the cost. Grinding, honing, and lapping are the recourse for when the limits of boring repeatability and accuracy have been met. \nSurface finish (roughness) in boring may range from 8 to 250 microinches, with a typical range between 32 and 125 microinches.\nSometimes a part may require higher accuracy of form and size than can be provided by boring. For example, even in optimized boring, the amount that the diameter varies on different portions of the bore is seldom less than 3 micrometre (.0001 inches, \"a tenth\"), and it may easily be 5 to 20 micrometre (.0002-.0008 inches, \"2 to 8 tenths\"). Taper, roundness error, and cylindricity error of such a hole, although they would be considered negligible in most other parts, may be unacceptable for a few applications. For such parts, internal cylindrical grinding is a typical follow-up operation. Often a part will be roughed and semifinished in the machining operation, then heat treated, and finally, finished by internal cylindrical grinding. \nThe limitations of boring in terms of its geometric accuracy (form, position) and the hardness of the workpiece have been shrinking in recent decades as machining technology continues to advance. For example, new grades of carbide and ceramic cutting inserts have increased the accuracy and surface quality that can be achieved without grinding, and have increased the range of workpiece hardness values that are workable. However, working to tolerances of only a few micrometres (a few tenths) forces the manufacturing process to rationally confront, and compensate for, the fact that no actual workpiece is ideally rigid and immobile. Each time a cut is taken (no matter how small), or a temperature change of a few hundred degrees takes place (no matter how temporary), the workpiece, or a portion of it, is likely to spring into a new shape, even if the movement is extremely small. In some cases a movement of a fraction of a micrometre in one area is amplified in lever fashion to create a positional error of several micrometres for a feature of the workpiece several decimetres away. It is factors such as these that sometimes preclude finishing by boring and turning as opposed to internal and external cylindrical grinding. At the extreme, no perfection of machining or grinding may be enough when, despite the part being within tolerance when it is made, it warps out of tolerance in following days or months. When engineers are confronted with such a case, it drives the quest to find other workpiece materials, or alternate designs that avoid relying so heavily on the immobility of part features on the micro or nano scales.", "Engineering,_Manufacturing": 0.9999740124, "qwen": "Yes"}
{"id": "33713553", "revid": "42522270", "url": "https://en.wikipedia.org/wiki?curid=33713553", "title": "Automated fiber placement", "text": "Automated fiber placement (AFP), also known as advanced fiber placement, is an advanced method of manufacturing composite materials. These materials, which offer lighter weight with equivalent or greater strength than metals, are increasingly used in airframes and other industrial products.\nFiber Placement is an automated composites manufacturing process of heating and compacting synthetic resin pre-impregnated non-metallic fibers on typically complex tooling mandrels. The fiber usually comes in the form of what are referred to as \"tows\". A tow is typically a bundle of carbon fibers impregnated with epoxy resin and is approximately wide by thick and comes on a spool. Fiber placement machines (FPM) generally have a capacity of 12 to 32 tows or when placing all tows at a time in a course, have respective course widths of 1.5 in to 4 in. The tows are fed to a heater and compaction roller on the FPM head and through robotic type machine movements, are placed in courses across a tool surface. Courses are generally placed in orientations of 0°, +45°, -45° and 90° to build up plies which in combination, have good properties in all directions. Fiber placement machines are generally rated in (lb/h), (lb/min) or weight per time.\nDescription.\nAutomated fiber placement (AFP) machines are a recent development of composite manufacturing technologies meant to increase rate and precision in the production of advanced composite parts. AFP machines place fiber reinforcements on moulds or mandrels in an automatic fashion and use a number of separate small width tows (typically or less) of thermoset or thermoplastic pre-impregnated materials to form composite layups. This technology allows better precision and increased deposition rates when compared with experienced laminators but, while allowing for more complex layup geometries than Automated Tape Laying (ATL) it does not reach the same deposition rates. Automated fiber placement can be used to manufacture complex structures that are not possible to manufacture with any other methods.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "33720874", "revid": "382591", "url": "https://en.wikipedia.org/wiki?curid=33720874", "title": "Arachno-Bot", "text": "Arachno-Bot is a printable spider robot built as an exploratory tool in environments that are too hazardous for humans. It gets its name because the robot's looks and movement are similar to a real spider. Fraunhofer Institute for Manufacturing Engineering and Automation in Stuttgart, Germany has developed Arachno-Bot by using a natural spider as the model for their robot, which was created through 3D printing.\nConstruction.\nArachno-Bot has eight legs just like a real spider and are operated by hydraulics while elastic bellows drives serve as joints. It is created using a 3D printing process called selective laser sintering. The process allows the robots to be quickly produced at a cheap cost.", "Engineering,_Manufacturing": 1.0000077486, "qwen": "Yes"}
{"id": "33731132", "revid": "10609380", "url": "https://en.wikipedia.org/wiki?curid=33731132", "title": "Gas metal arc welding", "text": "Gas metal arc welding (GMAW), sometimes referred to by its subtypes metal inert gas (MIG) and metal active gas (MAG) is a welding process in which an electric arc forms between a consumable MIG wire electrode and the workpiece metal(s), which heats the workpiece metal(s), causing them to fuse (melt and join). Along with the wire electrode, a shielding gas feeds through the welding gun, which shields the process from atmospheric contamination.\nThe process can be semi-automatic or automatic. A constant voltage, direct current power source is most commonly used with GMAW, but constant current systems, as well as alternating current, can be used. There are four primary methods of metal transfer in GMAW, called globular, short-circuiting, spray, and pulsed-spray, each of which has distinct properties and corresponding advantages and limitations.\nOriginally developed in the 1940s for welding aluminium and other non-ferrous materials, GMAW was soon applied to steels because it provided faster welding time compared to other welding processes. The cost of inert gas limited its use in steels until several years later, when the use of semi-inert gases such as carbon dioxide became common. Further developments during the 1950s and 1960s gave the process more versatility and as a result, it became a highly used industrial process. Today, GMAW is the most common industrial welding process, preferred for its versatility, speed and the relative ease of adapting the process to robotic automation. Unlike welding processes that do not employ a shielding gas, such as shielded metal arc welding, it is rarely used outdoors or in other areas of moving air. A related process, flux cored arc welding, often does not use a shielding gas, but instead employs an electrode wire that is hollow and filled with flux.\nDevelopment.\nThe principles of gas metal arc welding began to be understood in the early 19th century, after Humphry Davy discovered the short pulsed electric arcs in 1800. Vasily Petrov independently produced the continuous electric arc in 1802 (followed by Davy after 1808). It was not until the 1880s that the technology became developed with the aim of industrial usage. At first, carbon electrodes were used in carbon arc welding. By 1890, metal electrodes had been invented by Nikolay Slavyanov and C. L. Coffin. In 1920, an early predecessor of GMAW was invented by P. O. Nobel of General Electric. It used direct current with a bare electrode wire and used arc voltage to regulate the feed rate. It did not use a shielding gas to protect the weld, as developments in welding atmospheres did not take place until later that decade. In 1926 another forerunner of GMAW was released, but it was not suitable for practical use.\nIn 1948, GMAW was developed by the Battelle Memorial Institute. It used a smaller diameter electrode and a constant voltage power source developed by H. E. Kennedy. It offered a high deposition rate, but the high cost of inert gases limited its use to non-ferrous materials and prevented cost savings. In 1953, the use of carbon dioxide as a welding atmosphere was developed, and it quickly gained popularity in GMAW, since it made welding steel more economical. In 1958 and 1959, the short-arc variation of GMAW was released, which increased welding versatility and made the welding of thin materials possible while relying on smaller electrode wires and more advanced power supplies. It quickly became the most popular GMAW variation.\nThe spray-arc transfer variation was developed in the early 1960s, when experimenters added small amounts of oxygen to inert gases. More recently, pulsed current has been applied, giving rise to a new method called the pulsed spray-arc variation.\nGMAW is one of the most popular welding methods, especially in industrial environments. It is used extensively by the sheet metal industry and the automobile industry. There, the method is often used for arc spot welding, replacing riveting or resistance spot welding. It is also popular for automated welding, where robots handle the workpieces and the welding gun to accelerate manufacturing. GMAW can be difficult to perform well outdoors, since drafts can dissipate the shielding gas and allow contaminants into the weld; flux cored arc welding is better suited for outdoor use such as in construction. Likewise, GMAW's use of a shielding gas does not lend itself to underwater welding, which is more commonly performed via shielded metal arc welding, flux cored arc welding, or gas tungsten arc welding.\nEquipment.\nTo perform gas metal arc welding, the basic necessary equipment is a welding gun, a wire feed unit, a welding power supply, a welding electrode wire, and a shielding gas supply.\nWelding gun and wire feed unit.\nThe typical GMAW welding gun has a number of key parts—a control switch, a contact tip, a power cable, a gas nozzle, an electrode conduit and liner, and a gas hose. The control switch, or trigger, when pressed by the operator, initiates the wire feed, electric power, and the shielding gas flow, causing an electric arc to be struck. The contact tip, normally made of copper and sometimes chemically treated to reduce spatter, is connected to the welding power source through the power cable and transmits the electrical energy to the electrode while directing it to the weld area. It must be firmly secured and properly sized, since it must allow the electrode to pass while maintaining electrical contact. On the way to the contact tip, the wire is protected and guided by the electrode conduit and liner, which help prevent buckling and maintain an uninterrupted wire feed. The gas nozzle directs the shielding gas evenly into the welding zone. Inconsistent flow may not adequately protect the weld area. Larger nozzles provide greater shielding gas flow, which is useful for high current welding operations that develop a larger molten weld pool. A gas hose from the tanks of shielding gas supplies the gas to the nozzle. Sometimes, a water hose is also built into the welding gun, cooling the gun in high heat operations.\nThe wire feed unit supplies the electrode to the work, driving it through the conduit and on to the contact tip. Most models provide the wire at a constant feed rate, but more advanced machines can vary the feed rate in response to the arc length and voltage. Some wire feeders can reach feed rates as high as 30 m/min (1200 in/min), but feed rates for semiautomatic GMAW typically range from 2 to 10 m/min (75 – 400 in/min).\nTool style.\nThe most common electrode holder is a semiautomatic air-cooled holder. Compressed air circulates through it to maintain moderate temperatures. It is used with lower current levels for welding lap or butt joints. The second most common type of electrode holder is semiautomatic water-cooled, where the only difference is that water takes the place of air. It uses higher current levels for welding T or corner joints. The third typical holder type is a water cooled automatic electrode holder—which is typically used with automated equipment.\nPower supply.\nMost applications of gas metal arc welding use a constant voltage power supply. As a result, any change in arc length (which is directly related to voltage) results in a large change in heat input and current. A shorter arc length causes a much greater heat input, which makes the wire electrode melt more quickly and thereby restore the original arc length. This helps operators keep the arc length consistent even when manually welding with hand-held welding guns. To achieve a similar effect, sometimes a constant current power source is used in combination with an arc voltage-controlled wire feed unit. In this case, a change in arc length makes the wire feed rate adjust to maintain a relatively constant arc length. In rare circumstances, a constant current power source and a constant wire feed rate unit might be coupled, especially for the welding of metals with high thermal conductivities, such as aluminum. This grants the operator additional control over the heat input into the weld, but requires significant skill to perform successfully.\nAlternating current is rarely used with GMAW; instead, direct current is employed and the electrode is generally positively charged. Since the anode tends to have a greater heat concentration, this results in faster melting of the feed wire, which increases weld penetration and welding speed. The polarity can be reversed only when special emissive-coated electrode wires are used, but since these are not popular, a negatively charged electrode is rarely employed.\nElectrode.\nThe electrode is a metallic alloy wire, called a MIG wire, whose selection, alloy and size, is based primarily on the composition of the metal being welded, the process variation being used, joint design, and the material surface conditions. Electrode selection greatly influences the mechanical properties of the weld and is a key factor of weld quality. In general the finished weld metal should have mechanical properties similar to those of the base material with no defects such as discontinuities, entrained contaminants or porosity within the weld. To achieve these goals a wide variety of electrodes exist. All commercially available electrodes contain deoxidizing metals such as silicon, manganese, titanium and aluminum in small percentages to help prevent oxygen porosity. Some contain denitriding metals such as titanium and zirconium to avoid nitrogen porosity. Depending on the process variation and base material being welded the diameters of the electrodes used in GMAW typically range from 0.7 to 2.4 mm (0.028 – 0.095 in) but can be as large as 4 mm (0.16 in). The smallest electrodes, generally up to 1.14 mm (0.045 in) are associated with the short-circuiting metal transfer process, while the most common spray-transfer process mode electrodes are usually at least 0.9 mm (0.035 in).\nShielding gas.\nShielding gases are necessary for gas metal arc welding to protect the welding area from atmospheric gases such as nitrogen and oxygen, which can cause fusion defects, porosity, and weld metal embrittlement if they come in contact with the electrode, the arc, or the welding metal. This problem is common to all arc welding processes; for example, in the older Shielded-Metal Arc Welding process (SMAW), the electrode is coated with a solid flux which evolves a protective cloud of carbon dioxide when melted by the arc. In GMAW, however, the electrode wire does not have a flux coating, and a separate shielding gas is employed to protect the weld. This eliminates slag, the hard residue from the flux that builds up after welding and must be chipped off to reveal the completed weld.\nThe choice of a shielding gas depends on several factors, most importantly the type of material being welded and the process variation being used. Pure inert gases such as argon and helium are only used for nonferrous welding; with steel they do not provide adequate weld penetration (argon) or cause an erratic arc and encourage spatter (with helium). Pure carbon dioxide, on the other hand, allows for deep penetration welds but encourages oxide formation, which adversely affects the mechanical properties of the weld. lts low cost makes it an attractive choice, but because of the reactivity of the arc plasma, spatter is unavoidable and welding thin materials is difficult. As a result, argon and carbon dioxide are frequently mixed in a 75%/25% to 90%/10% mixture. Generally, in short circuit GMAW, higher carbon dioxide content increases the weld heat and energy when all other weld parameters (volts, current, electrode type and diameter) are held the same. As the carbon dioxide content increases over 20%, spray transfer GMAW becomes increasingly problematic, especially with smaller electrode diameters.\nArgon is also commonly mixed with other gases, oxygen, helium, hydrogen and nitrogen. The addition of up to 5% oxygen (like the higher concentrations of carbon dioxide mentioned above) can be helpful in welding stainless steel, however, in most applications carbon dioxide is preferred. Increased oxygen makes the shielding gas oxidize the electrode, which can lead to porosity in the deposit if the electrode does not contain sufficient deoxidizers. Excessive oxygen, especially when used in application for which it is not prescribed, can lead to brittleness in the heat affected zone. Argon-helium mixtures are extremely inert, and can be used on nonferrous materials. A helium concentration of 50–75% raises the required voltage and increases the heat in the arc, due to helium's higher ionization temperature. Hydrogen is sometimes added to argon in small concentrations (up to about 5%) for welding nickel and thick stainless steel workpieces. In higher concentrations (up to 25% hydrogen), it may be used for welding conductive materials such as copper. However, it should not be used on steel, aluminum or magnesium because it can cause porosity and hydrogen embrittlement.\nShielding gas mixtures of three or more gases are also available. Mixtures of argon, carbon dioxide and oxygen are marketed for welding steels. Other mixtures add a small amount of helium to argon-oxygen combinations. These mixtures are claimed to allow higher arc voltages and welding speed. Helium also sometimes serves as the base gas, with small amounts of argon and carbon dioxide added. However, because it is less dense than air, helium is less effective at shielding the weld than argon—which is denser than air. It also can lead to arc stability and penetration issues, and increased spatter, due to its much more energetic arc plasma. Helium is also substantially more expensive than other shielding gases. Other specialized and often proprietary gas mixtures claim even greater benefits for specific applications.\nDespite being poisonous, trace amounts of nitric oxide can be used to prevent the even more troublesome ozone from being formed in the arc.\nThe desirable rate of shielding-gas flow depends primarily on weld geometry, speed, current, the type of gas, and the metal transfer mode. Welding flat surfaces requires higher flow than welding grooved materials, since gas disperses more quickly. Faster welding speeds, in general, mean that more gas must be supplied to provide adequate coverage. Additionally, higher current requires greater flow, and generally, more helium is required to provide adequate coverage than if argon is used. Perhaps most importantly, the four primary variations of GMAW have differing shielding gas flow requirements—for the small weld pools of the short circuiting and pulsed spray modes, about 10 L/min (20 ft3/h) is generally suitable, whereas for globular transfer, around 15 L/min (30 ft3/h) is preferred. The spray transfer variation normally requires more shielding-gas flow because of its higher heat input and thus larger weld pool. Typical gas-flow amounts are approximately 20–25 L/min (40–50 ft3/h).\nGMAW-based 3-D printing.\nGMAW has also been used as a low-cost method to 3-D print metal objects. Various open source 3-D printers have been developed to use GMAW. Such components fabricated from aluminum compete with more traditionally manufactured components on mechanical strength. By forming a bad weld on the first layer, GMAW 3-D printed parts can be removed from the substrate with a hammer.\nOperation.\nFor most of its applications gas metal arc welding is a fairly simple welding process to learn requiring no more than a week or two to master basic welding technique. Even when welding is performed by well-trained operators weld quality can fluctuate since it depends on a number of external factors. All GMAW is dangerous, though perhaps less so than some other welding methods, such as shielded metal arc welding.\nTechnique.\nGMAW's basic technique is uncomplicated, with most individuals able to achieve reasonable proficiency in a few weeks, assuming proper training and sufficient practice. As much of the process is automated, GMAW relieves the welder (operator) of the burden of maintaining a precise arc length, as well as feeding filler metal into the weld puddle, coordinated operations that are required in other manual welding processes, such as shielded metal arc. GMAW requires only that the welder guide the gun with proper position and orientation along the area being welded, as well as periodically clean the gun's gas nozzle to remove spatter buildup. Additional skill includes knowing how to adjust the welder so the voltage, wire feed rate and gas flow rate are correct for the materials being welded and the wire size being employed.\nMaintaining a relatively constant contact tip-to-work distance (the \"stick-out\" distance) is important. Excessive stick-out distance may cause the wire electrode to prematurely melt, causing a sputtering arc, and may also cause the shielding gas to rapidly disperse, degrading the quality of the weld. In contrast, insufficient stick-out may increase the rate at which spatter builds up inside the gun's nozzle and in extreme cases, may cause damage to the gun's contact tip. Stick-out distance varies for different GMAW weld processes and applications.\nThe orientation of the gun relative to the weldment is also important. It should be held so as to bisect the angle between the workpieces; that is, at 45 degrees for a fillet weld and 90 degrees for welding a flat surface. The travel angle, or lead angle, is the angle of the gun with respect to the direction of travel, and it should generally remain approximately vertical. However, the desirable angle changes somewhat depending on the type of shielding gas used—with pure inert gases, the bottom of the torch is often slightly in front of the upper section, while the opposite is true when the welding atmosphere is carbon dioxide.\nPosition welding, that is, welding vertical or overhead joints, may require the use of a weaving technique to assure proper weld deposition and penetration. In position welding, gravity tends to cause molten metal to run out of the puddle, resulting in cratering and undercutting, two conditions that produce a weak weld. Weaving constantly moves the fusion zone around so as to limit the amount of metal deposited at any one point. Surface tension then assists in keeping the molten metal in the puddle until it is able to solidify. Development of position welding skill takes some experience, but is usually soon mastered.\nQuality.\nTwo of the most prevalent quality problems in GMAW are dross and porosity. If not controlled, they can lead to weaker, less ductile welds. Dross is an especially common problem in aluminium GMAW welds, normally coming from particles of aluminium oxide or aluminum nitride present in the electrode or base materials. Electrodes and workpieces must be brushed with a wire brush or chemically treated to remove oxides on the surface. Any oxygen in contact with the weld pool, whether from the atmosphere or the shielding gas, causes dross as well. As a result, sufficient flow of inert shielding gases is necessary, and welding in moving air should be avoided.\nIn GMAW the primary cause of porosity is gas entrapment in the weld pool, which occurs when the metal solidifies before the gas escapes. The gas can come from impurities in the shielding gas or on the workpiece, as well as from an excessively long or violent arc. Generally, the amount of gas entrapped is directly related to the cooling rate of the weld pool. Because of its higher thermal conductivity, aluminum welds are especially susceptible to greater cooling rates and thus additional porosity. To reduce it, the workpiece and electrode should be clean, the welding speed diminished and the current set high enough to provide sufficient heat input and stable metal transfer but low enough that the arc remains steady. Preheating can also help reduce the cooling rate in some cases by reducing the temperature gradient between the weld area and the base metal.\nSafety.\nArc welding in any form can be dangerous if proper precautions are not taken. Since GMAW employs an electric arc, welders must wear suitable protective clothing, including heavy gloves and protective long sleeve jackets, to minimize exposure to the arc itself, as well as intense heat, sparks and hot metal. The intense ultraviolet radiation of the arc may cause sunburn-like damage to exposed skin, as well a condition known as arc eye, an inflammation of the cornea, or in cases of prolonged exposure, irreversible damage to the eye's retina. Conventional welding helmets contain dark face plates to prevent this exposure. Newer helmet designs feature a liquid crystal-type face plate that self-darkens upon exposure to the arc. Transparent welding curtains, made of a polyvinyl chloride plastic film, are often used to shield nearby workers and bystanders from exposure to the arc.\nWelders are often exposed to hazardous gases and airborne particulate matter. GMAW produces smoke containing particles of various types of oxides, and the size of the particles tends to influence the toxicity of the fumes. Smaller particles present greater danger. Concentrations of carbon dioxide and ozone can prove dangerous if ventilation is inadequate. Other precautions include keeping combustible materials away from the workplace, and having a working fire extinguisher nearby.\nMetal transfer modes.\nThe three transfer modes in GMAW are globular, short-circuiting, and spray. There are a few recognized variations of these three transfer modes including modified short-circuiting and pulsed-spray.\nGlobular.\nGMAW with globular metal transfer is considered the least desirable of the three major GMAW variations, because of its tendency to produce high heat, a poor weld surface, and spatter. The method was originally developed as a cost efficient way to weld steel using GMAW, because this variation uses carbon dioxide, a less expensive shielding gas than argon. Adding to its economic advantage was its high deposition rate, allowing welding speeds of up to 110 mm/s (250 in/min). As the weld is made, a ball of molten metal from the electrode tends to build up on the end of the electrode, often in irregular shapes with a larger diameter than the electrode itself. When the droplet finally detaches either by gravity or short circuiting, it falls to the workpiece, leaving an uneven surface and often causing spatter. As a result of the large molten droplet, the process is generally limited to flat and horizontal welding positions, requires thicker workpieces, and results in a larger weld pool.\nShort-circuiting.\nFurther developments in welding steel with GMAW led to a variation known as short-circuit transfer (SCT) or short-arc GMAW, in which the current is lower than for the globular method. As a result of the lower current, the heat input for the short-arc variation is considerably reduced, making it possible to weld thinner materials while decreasing the amount of distortion and residual stress in the weld area. As in globular welding, molten droplets form on the tip of the electrode, but instead of dropping to the weld pool, they bridge the gap between the electrode and the weld pool as a result of the lower wire feed rate. This causes a short circuit and extinguishes the arc, but it is quickly reignited after the surface tension of the weld pool pulls the molten metal bead off the electrode tip. This process is repeated about 100 times per second, making the arc appear constant to the human eye. This type of metal transfer provides better weld quality and less spatter than the globular variation, and allows for welding in all positions, albeit with slower deposition of weld material. Setting the weld process parameters (volts, amps and wire feed rate) within a relatively narrow band is critical to maintaining a stable arc: generally between 100 and 200 amperes at 17 to 22 volts for most applications. Also, using short-arc transfer can result in lack of fusion and insufficient penetration when welding thicker materials, due to the lower arc energy and rapidly freezing weld pool. Like the globular variation, it can only be used on ferrous metals.\nCold Metal Transfer.\nFor thin materials, Cold Metal Transfer (CMT) is used by reducing the current when a short circuit is registered, producing many drops per second. CMT can be used for aluminum.\nSpray.\nSpray transfer GMAW was the first metal transfer method used in GMAW, and well-suited to welding aluminium and stainless steel while employing an inert shielding gas. In this GMAW process, the weld electrode metal is rapidly passed along the stable electric arc from the electrode to the workpiece, essentially eliminating spatter and resulting in a high-quality weld finish. As the current and voltage increases beyond the range of short circuit transfer the weld electrode metal transfer transitions from larger globules through small droplets to a vaporized stream at the highest energies. Since this vaporized spray transfer variation of the GMAW weld process requires higher voltage and current than short circuit transfer, and as a result of the higher heat input and larger weld pool area (for a given weld electrode diameter), it is generally used only on workpieces of thicknesses above about 6.4 mm (0.25 in).\nAlso, because of the large weld pool, it is often limited to flat and horizontal welding positions and sometimes also used for vertical-down welds. It is generally not practical for root pass welds. When a smaller electrode is used in conjunction with lower heat input, its versatility increases. The maximum deposition rate for spray arc GMAW is relatively high—about 600 mm/s (1500 in/min).\nPulsed-spray.\nA variation of the spray transfer mode, pulse-spray is based on the principles of spray transfer but uses a pulsing current to melt the filler wire and allow one small molten droplet to fall with each pulse. The pulses allow the average current to be lower, decreasing the overall heat input and thereby decreasing the size of the weld pool and heat-affected zone while making it possible to weld thin workpieces. The pulse provides a stable arc and no spatter, since no short-circuiting takes place. This also makes the process suitable for nearly all metals, and thicker electrode wire can be used as well. The smaller weld pool gives the variation greater versatility, making it possible to weld in all positions. In comparison with short arc GMAW, this method has a somewhat slower maximum speed (85 mm/s or 200 in/min) and the process also requires that the shielding gas be primarily argon with a low carbon dioxide concentration. Additionally, it requires a special power source capable of providing current pulses with a frequency between 30 and 400 pulses per second. However, the method has gained popularity, since it requires lower heat input and can be used to weld thin workpieces, as well as nonferrous materials.\nComparison with flux-cored wire-fed arc welding.\nFlux-cored, self-shielding or gasless wire-fed welding had been developed for simplicity and portability. This avoids the gas system of conventional GMAW and uses a cored wire containing a solid flux. This flux vaporises during welding and produces a plume of shielding gas. Although described as a 'flux', this compound has little activity and acts mostly as an inert shield. The wire is of slightly larger diameter than for a comparable gas-shielded weld, to allow room for the flux. The smallest available is 0.8 mm diameter, compared to 0.6 mm for solid wire. The shield vapor is slightly active, rather than inert, so the process is always MAGS but not MIG (inert gas shield). This limits the process to steel and not aluminium.\nThese gasless machines operate as DCEN, rather than the DCEP usually used for GMAW solid wire. DCEP, or DC Electrode Positive, makes the welding wire into the positively-charged anode, which is the hotter side of the arc. Provided that it is switchable from DCEN to DCEP, a gas-shielded wire-feed machine may also be used for flux-cored wire.\nFlux-cored wire is considered to have some advantages for outdoor welding on-site, as the shielding gas plume is less likely to be blown away in a wind than shield gas from a conventional nozzle. A slight drawback is that, like SMAW (stick) welding, there may be some flux deposited over the weld bead, requiring more of a cleaning process between passes.\nFlux-cored welding machines are most popular at the hobbyist level, as the machines are slightly simpler but mainly because they avoid the cost of providing shield gas, either through a rented cylinder or with the high cost of disposable cylinders.", "Engineering,_Manufacturing": 0.9997444749, "qwen": "Yes"}
{"id": "56543723", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=56543723", "title": "3D makeR Technologies", "text": "3D makeR Technologies (makeR) is a 3D printer manufacturer. The company started out as an open-source printer company. It was founded between Barcelona and Santa Marta by Carlos Camargo, who currently acts as the CEO of the company. Following the traditional RepRap model, the makeR's first products were as do it yourself kits with an alternative version based on open-source FDM 3D printer Prusa i3, called Prusa Tairona. Current makeR 3D printers are designed with a closed frame and selected build sizes.\nProducts.\nTheir product line includes the 3D printer series PEGASUS. The makeR 3D printers are compatible with polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), thermoplastic polyurethane (TPU), high-impact polystyrene (HIPS), polyvinyl alcohol (PVA) and some specials materials for industrial needs, such as PLA filament mixed with particles of metals which through sanding 3D printed parts provide appearance similar to metals (steel, copper, and aluminium). Also, makeR printers print with nylon and carbon fiber.", "Engineering,_Manufacturing": 0.995860815, "qwen": "Yes"}
{"id": "6739307", "revid": "10077638", "url": "https://en.wikipedia.org/wiki?curid=6739307", "title": "Industrial finishing", "text": "Industrial finishing is any kind of secondary process done to any metal, plastic, or wood product used in a common market such as automotive, OEM, telecommunications or point-of-purchase. The most common commodity in the industrial finishing market is plastic parts. These can be injection molded, thermoformed, extruded or vacuum formed. Most parts are painted but can be pad printed or silkscreened.\nOne finishing process is vacuum metalising.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "6746671", "revid": "23914831", "url": "https://en.wikipedia.org/wiki?curid=6746671", "title": "Wafer dicing", "text": "In the context of manufacturing integrated circuits, wafer dicing is the process by which die are separated from a wafer of semiconductor following the processing of the wafer. The dicing process can involve scribing and breaking, mechanical sawing (normally with a machine called a \"dicing saw\") or laser cutting. All methods are typically automated to ensure precision and accuracy.\nFollowing the dicing process the individual silicon chips may be encapsulated into chip carriers which are then suitable for use in building electronic devices such as computers, etc.\nDuring dicing, wafers are typically mounted on dicing tape which has a sticky backing that holds the wafer on a thin sheet metal frame. Dicing tape has different properties depending on the dicing application. UV curable tapes are used for smaller sizes and non-UV dicing tape for larger die sizes. Dicing saws may use a dicing blade with diamond particles, rotating at 30,000 RPM and cooled with deionized water. Once a wafer has been diced, the pieces left on the dicing tape are referred to as \"die\", \"dice\" or \"dies\". Each will be packaged in a suitable package or placed directly on a printed circuit board substrate as a \"bare die\". The areas that have been cut away, called \"die streets\", are typically about 75 micrometres (0.003 inch) wide. Once a wafer has been diced, the die will stay on the dicing tape until they are extracted by die-handling equipment, such as a \"die bonder\" or \"die sorter\", further in the electronics assembly process.\nThe size of the die left on the tape may range from 35 mm on a side (very large) to 0.1 mm square (very small). The die created may be any shape generated by straight lines, but they are typically rectangular or square-shaped. In some cases they can be other shapes as well depending on the singulation method used. A full-cut laser dicer has the ability to cut and separate in a variety of shapes.\nMaterials diced include glass, alumina, silicon, gallium arsenide (GaAs), silicon on sapphire (SoS), ceramics, and delicate compound semiconductors.\nStealth dicing.\nDicing of silicon wafers may also be performed by a laser-based technique, the so-called stealth dicing process. It works as a two-stage process in which defect regions are firstly introduced into the wafer by scanning the beam along intended cutting lines and secondly an underlying carrier membrane is expanded to induce fracture.\nThe first step operates with a pulsed , the wavelength of which (1064 nm) is well adapted to the electronic band gap of silicon (1.11 eV or 1117 nm), so that maximum absorption may well be adjusted by optical focusing. Defect regions of about 10 µm width are inscribed by multiple scans of the laser along the intended dicing lanes, where the beam is focused at different depths of the wafer. The figure displays an optical micrograph of a cleavage plane of a separated chip of 150 µm thickness that was subjected to four laser scans, compare. The topmost defects are the best resolved and it is realized that a single laser pulse causes a defected crystal region that resembles the shape of candle flame. This shape is caused by the rapid melting and solidification of the irradiated region in the laser beam focus, where the temperature of only some µm3 small volumes suddenly rises to some 1000 K within nanoseconds and falls to ambient temperature again. The laser is typically pulsed by a frequency of about 100 kHz, while the wafer is moved with a velocity of about 1 m/s. A defected region of about 10 µm width is finally inscribed in the wafer, along which preferential fracture occurs under mechanical loading. The fracture is performed in the second step and operates by radially expanding the carrier membrane to which the wafer is attached. The cleavage initiates at the bottom and advances to the surface, from which it is understood that a high distortion density must be introduced at the bottom.\nIt is the advantage of the stealth dicing process that it does not require a cooling liquid. Dry dicing methods inevitably have to be applied for the preparation of certain microelectromechanical systems (MEMS), in particular, when these are intended for bioelectronic applications. In addition, stealth dicing hardly generates debris and allows for improved exploitation of the wafer surface due to smaller kerf loss compared to wafer saw. Wafer grinding may be performed after this step, to reduce die thickness.\nDice before grind.\nThe DBG or \"dice before grind\" process is a way to separate dies without dicing. The separation occurs during the wafer thinning step. The wafers are initially diced using a half-cut dicer to a depth below the final target thickness. Next, the wafer is thinned to the target thickness while mounted on a special adhesive film and then mounted on to a pick-up tape to hold the dies in place until they are ready for the packaging step. The benefit to the DBG process is higher die strength. Alternatively, plasma dicing may be used, which replaces the dicer's saw with DRIE plasma etching.\nThe DBG process requires a back grinding tape that has the following attributes, 1) strong adhesive force (prevents infiltration of grinding fluid and die dust during grinding), 2) absorption and/or relief of compression stress and shear stress during grinding, 3) suppresses cracking due to contact between dies, 4) adhesive strength that can be greatly reduced through UV irradiation.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "4932508", "revid": "1097757554", "url": "https://en.wikipedia.org/wiki?curid=4932508", "title": "Electric platform truck", "text": "Electric platform trucks are electric powered trucks with a large flat surface for holding objects to be transported. Some are also called warehouse utility vehicles, electric trolley carts, or powered platform truck vehicles. Electric platform trucks can vary greatly in size, from large ride-on utility vehicles, to much smaller pedestrian operated trolleys. Electric tugs can be combined with nonpowered carts or hand trucks to achieve the same result.\nA milk float is a specialised version of an electric platform truck specifically designed for the delivery of fresh milk, common in the United Kingdom.", "Engineering,_Manufacturing": 1.0000027418, "qwen": "Yes"}
{"id": "2910429", "revid": "7770027", "url": "https://en.wikipedia.org/wiki?curid=2910429", "title": "Supply network", "text": "A supply network is a pattern of temporal and spatial processes carried out at facility nodes and over distribution links, which adds value for customers through the manufacturing and delivery of products. It comprises the general state of business affairs in which all kinds of material (work-in-process material as well as finished products) are transformed and moved between various value-added points to maximize the value added for customers. In the semiconductor industry, for example, work-in-process moves from fabrication to assembly, and then to the test house. The term \"supply network\" refers to the high-tech phenomenon of contract manufacturing where the brand owner does not touch the product. Instead, she coordinates with contract manufacturers and component suppliers who ship components to the brand owner. This business practice requires the brand owner to stay in touch with multiple parties or \"network\" at once.\nA supply chain is a special instance of a supply network in which raw materials, intermediate materials and finished goods are procured exclusively as products through a chain of processes that supply one another.\nResilient supply networks.\nA resilient supply network effectively aligns its strategy, operations, management systems, governance structure, and decision-support capabilities so that it can uncover and adjust to continually changing risks, endure disruptions to its primary earnings drivers, and create advantages over less adaptive competitors. Moreover, it has the capability to respond rapidly to unforeseen changes, even chaotic disruption. The resilience of a supply network is the ability to bounce back – and, in fact, to bounce forward with speed, determination and precision. In recent studies, resilience is regarded as the next phase in the evolution of traditional, place-centric enterprise structures to highly virtualized, customer-centric structures that enable people to work anytime, anywhere.\nResilient supply networks should align its strategy and operations to adapt to risk that affects its capacities. There are 4 levels of supply chain resilience:\nStrategic resilience.\nFrom the strategic resilient viewpoint, a supply network must dynamically reinvent business models and strategies as circumstances change. It is not about responding to a one-time crisis, or just having a flexible supply chain. It is about continuously anticipating and adjusting to discontinuities that can permanently impair the value preposition of a core business with focus on delivering customer satisfaction. Strategic resilience requires continuous innovation with respect to product structures, processes, but also corporate behaviour. Renewal can be regarded as the natural consequence of a supply network’s innate strategic resilience. \nOperational resilience.\nIn terms of operational resilience, the supply networks must respond to the ups and downs of the business cycle or to quickly rebalance product-service mix, processes, and supply chain, by bolstering enterprises agility, flexibility and robustness in the face of changing environments.", "Engineering,_Manufacturing": 0.9980673194, "qwen": "Yes"}
{"id": "2910667", "revid": "1066661355", "url": "https://en.wikipedia.org/wiki?curid=2910667", "title": "Cylinder blown sheet glass", "text": "Cylinder blown sheet is a type of hand-blown window glass. It is created with a similar process to broad sheet, but with the use of larger cylinders. In this manufacturing process glass is blown into a cylindrical iron mold. The ends are cut off and a cut is made down the side of the cylinder. The cut cylinder is then placed in an oven where the cylinder unrolls into a flat glass sheet. William J. Blenko used this method in the early 1900s to make stained glass. The result is much larger panes and improved surface quality over broad sheet, although still containing some imperfections. These imperfect panes have led to the misconception that glass is actually a high-viscosity fluid at room temperature, which is not the case.\nThis method caused surface damages on the glass due to the flattening and moving, and the sheet therefore had to be ground and polished. In 1839 the Chance Brothers invented the patent plate process where the glass plate was placed on a wet piece of leather and ground and polished to remove all the surface damage.\nOther methods of producing hand-blown window glass included broad sheet, blown plate, crown glass and polished plate. These methods of manufacture lasted at least until the end of the 19th century. The early 20th century marks the move away from hand-blown to machine manufactured glass such as rolled plate, machine drawn cylinder sheet, the Fourcault process of flat drawn sheet, single and twin ground polished plate and most common, float glass.\nCylinder blown sheet glass was manufactured in the UK in the mid 19th century. It had been manufactured in France and Germany (and imported to the UK) since the 18th century.", "Engineering,_Manufacturing": 0.9999947548, "qwen": "Yes"}
{"id": "1302737", "revid": "1167233688", "url": "https://en.wikipedia.org/wiki?curid=1302737", "title": "Toyota Group", "text": "The is a group of companies that have supplier, vendor and investment relationships with Toyota Industries and Toyota Motor vehicle manufacturing facilities. It is similar to a \"keiretsu\" in that no particular entity has outright control over the entire group, although unlike most \"keiretsu\" it does not contain a major bank.\nMajor group companies.\nThere are 16 major companies that make up the Toyota Group:", "Engineering,_Manufacturing": 0.9989040494, "qwen": "Yes"}
{"id": "1303192", "revid": "1101750", "url": "https://en.wikipedia.org/wiki?curid=1303192", "title": "Toyota Motor North America", "text": "Toyota Motor North America (TMNA) is the operating subsidiary that oversees all operations of the Toyota Motor Corporation in Canada, Mexico, and the United States. Its operations include research and development, manufacturing, sales, marketing, after sales and corporate functions, which are controlled by TMNA but sometimes executed by other subsidiaries and holding companies. The company is headquartered in Plano, Texas, with offices in several locations including Georgetown, Kentucky, Ann Arbor, Michigan, Washington, D.C., and New York City.\nToyota’s operations in North America began on October 31, 1957, and today's Toyota Motor North America was established in 2017 from the consolidation of three companies: Toyota Motor North America, Inc., which controlled Toyota’s corporate functions; Toyota Motor Sales, U.S.A., Inc. which handled marketing, sales, and distribution in the United States; and Toyota Motor Engineering & Manufacturing North America which oversaw operations at all assembly plants in the region. While all three companies continue to exist in legal name, they operate as one company out of one headquarters campus.\nHistory.\nBeginnings in North America (1957–1979).\nIn August 1957, Toyota sent three employees to the United States to show off the company's new car, the Toyopet Crown to car dealers and the media to gauge interest in expanding sales overseas. The vehicle received positive reviews, with media outlets praising the vehicle for having 50% thicker steel than the average American car at the time and the black Deluxe model for being nicely appointed with lots of chrome and luxurious items like a radio, heater and whitewall tires which prompted the press to liken it to a \"baby Cadillac\". But Toyota knew from testing that the vehicle, designed for the muddy, slow, unpaved roads of Japan, had serious high-speed performance issues. When the Crown was driven on a highway, the engine suddenly began making loud noises and output dropped. But the promising initial showing, along with the strong reputation of the Crown in Japan gave Toyota a false sense of confidence and the company started to pursue exports to the United States.\nToyota’s operations in North America officially began on October 31, 1957 with the establishment of Toyota Motor Sales, U.S.A., Inc. (TMS) which oversaw sales, marketing, and distribution of Toyota’s vehicles in the United States. The fledgling company's headquarters was located in a former Rambler dealership in Hollywood, California with a warehouse near the harbor where vehicles would be imported in Long Beach, California. Sales started on July 10, 1958, and by the end of the year, the company sold 287 Toyopet Crown sedans and one Toyota Land Cruiser.\nThe company faced problems almost immediately. American automakers saw the increase in sales of imported compact cars and launched several compact cars from the autumn of 1959, including the Chevrolet Corvair, Ford Falcon, and Chrysler Valiant. As a result, sales of imported European cars plunged and the Crown was a flop with buyers finding it underpowered (due to the known high-speed performance issues) and overpriced. In response, exports of the Crown to the United States were suspended in December 1960. However, the Land Cruiser gained a following, allowing the company to make a profit in 1961, but there was not yet a major market for sport-utility vehicles in the United States.\nThe company's first major success in the United States came in 1965 with the Toyota Corona compact car, which was redesigned specifically for the American market with a more powerful engine, factory-installed air conditioning and an automatic transmission. The Corona helped increase U.S. sales of Toyota vehicles to more than 20,000 units in 1966 (a threefold increase) and helped the company become the third-best-selling import brand in the United States by 1967. In 1968, the Toyota Corolla subcompact car was introduced to the United States and would go on to become the world’s all-time best-selling automobile. This success led Toyota to establish a more permanent presence in North America, opening a headquarters building in Torrance, California, south of Los Angeles in February 1967.\nThe energy crisis of the 1970s was a major turning point in the American auto industry. Before the crisis, large and heavy vehicles with powerful but inefficient engines were common. But in the years after, consumers started demanding high-quality and fuel-efficient small cars. Domestic automakers, in the midst of their malaise era, struggled to build these cars profitably, but foreign automakers like Toyota were well positioned. This, along with growing anti-Japanese sentiment, prompted the U.S. Congress to consider import restrictions to protect the domestic auto industry.\nToyota’s first manufacturing investment in the United States came in 1972 when the company struck a deal with Atlas Fabricators, to produce truck beds in Long Beach, in an effort to avoid the 25% \"chicken tax\" on imported light trucks. By importing the truck as an incomplete chassis cab (the truck without a bed), the vehicle only faced a 4% tariff. Once in the United States, Atlas would build the truck beds and attach them to the trucks. The partnership was successful and two years later, Toyota purchased Atlas (which had been financially struggling) and it would eventually be renamed Toyota Auto Body California (TABC) as part of the company's Toyota Auto Body manufacturing subsidiary.\nToyota also began designing automobiles and conducting research and development in the United States in the 1970s to better understand and reflect the tastes of American consumers. Calty Design Research was established in California in 1973 and Toyota Technical Center, U.S.A. (TTC, later renamed TMNA R&D) was established in 1977 in the town of Ann Arbor, Michigan, not far from Detroit, the center of automobile manufacturing in the United States.\nInvesting in America (1980–1989).\nAfter the successes of the 1970s, and the threats of import restrictions, Toyota started making additional investments in the North American market in the 1980s. In 1981, Japan agreed to voluntary export restraints, which limited the number of vehicles the nation would send to the United States each year, leading Toyota to establish assembly plants in North America. The U.S. government also closed the loophole that allowed Toyota to pay lower taxes by building truck beds in America. Despite those challenges, Toyota also expanded its headquarters in Torrance, California into a larger campus of buildings in 1982, as the company marked 25 years in America.\nEfforts to open a Toyota assembly plant in the United States started in 1980, with the company proposing a joint-venture with the Ford Motor Company. Those talks broke down in July 1981. Eventually in 1984, the company struck a deal with General Motors (GM) to establish a joint-venture vehicle manufacturing plant called NUMMI (New United Motor Manufacturing, Inc.) in Fremont, California. GM saw the joint venture as a way to get access to a quality small car and an opportunity to learn about the Toyota Production System and The Toyota Way, a series of lean manufacturing and management philosophies. For Toyota, the factory gave the company its first manufacturing base in North America allowing it to avoid any future tariffs on imported vehicles and saw GM as a partner who could show them how to navigate the American labor environment. The first Toyota assembled in America, a white Corolla, rolled off the line at NUMMI on October 7, 1986. In 1991, Toyota started building pickup trucks at NUMMI, allowing the company to completely avoid the chicken tax.\nToyota took the lessons it learned from NUMMI and went onto establish the wholly-owned Toyota Motor Manufacturing USA (later renamed Toyota Motor Manufacturing Kentucky) and Toyota Motor Manufacturing Canada plants in 1986. The Kentucky plant was Toyota's largest manufacturing facility in the world, a title it continues to hold and the Canadian operation would later expand to three separate plants that comprise Toyota's second largest manufacturing facility.\nBefore the decade was out, Toyota introduced Lexus, a new division that was formed to market and service luxury vehicles in international markets, including North America. Prior to the debut, Toyota's two existing flagship models, the Crown and Century, both catered exclusively for the Japanese market and had little global appeal that could compete with international luxury brands such as Mercedes-Benz, BMW and Jaguar. The company had been developing the brand and vehicles in secret since August 1983, at a cost of over US$1 billion. The LS 400 flagship full-size sedan debuted in 1989 to strong sales, and was largely responsible for the successful launch of the Lexus marque.\nManufacturing expansion (1990–2009).\nIn 1990, Toyota purchased Bodine Aluminum (later renamed Toyota Motor Manufacturing Missouri and Toyota Motor Manufacturing Tennessee) which had three plants in St. Louis and Troy, Missouri, and Jackson, Tennessee to produce cast aluminum engine components for use in other manufacturing facilities.\nIn 1996, the company established two more manufacturing facilities: the Toyota Motor Manufacturing Indiana assembly plant in Princeton, Indiana and the Toyota Motor Manufacturing West Virginia engine and transmission plant in Buffalo, West Virginia. At the same time, the automaker also created the Toyota Motor Manufacturing North America (TMMNA) subsidiary in Erlanger, Kentucky to oversee all Toyota manufacturing operations in North America.\nToyota Motor Manufacturing Alabama, another engine plant was established 2001 in Huntsville, Alabama.\nNext, Toyota shifted to expanding its truck producing capacity, building two specialized assembly plants. Toyota Motor Manufacturing de Baja California was established in Tijuana in 2002, becoming the company's first assembly plant in Mexico, which was followed by Toyota Motor Manufacturing Texas in San Antonio in 2003.\nTMMNA would merge with the Toyota Technical Center, U.S.A. (TTC) research and development subsidiary in April 2006 to form Toyota Motor Engineering & Manufacturing North America, Inc. (TEMA).\nAnother assembly plant, Toyota Motor Manufacturing Mississippi was established in Blue Springs, Mississippi in 2007.\nToyota in North America today.\nThe NUMMI plant was closed in March 2010, after GM pulled out of the joint venture amid a Chapter 11 bankruptcy reorganization. It marked the first time the company had ever closed a factory. The plant was Toyota's only unionized plant in the U.S. and the company said that it was no longer economical to have a plant so far away from the supplier lines it had established in the Midwest.\nThe current Toyota Motor North America company was established in 2017 as part of the \"One Toyota\" initiative, TMS and TEMA combined with Toyota Motor North America, Inc. (TMA), which controlled Toyota’s corporate functions, to form Toyota Motor North America. While the three companies continue to exist in legal name, they operate as one company out of one headquarters campus in Plano, Texas. Toyota continues to operate research and design centers in Michigan and in October 2017 opened a new Production Engineering and Manufacturing Center (PEMC) in Georgetown, Kentucky, to serve as the go-between for design and manufacturing.\nToyota opened its second assembly plant in Mexico in 2019, Toyota Motor Manufacturing de Guanajuato located in Apaseo el Grande, which would also specialize in producing pickup trucks.\nSubsidiaries and related operations.\nManufacturing.\nToyota Motor North America operates several manufacturing facilities in North America through its Toyota Motor Engineering & Manufacturing North America, Inc. (TEMA) subsidiary.\nProducts.\nIn North America, Toyota sells a wide range of vehicles, including sedans, pickup trucks, a minivan, sport utility vehicles, and crossover SUVs.", "Engineering,_Manufacturing": 1.0000016689, "qwen": "Yes"}
{"id": "1304420", "revid": "636570", "url": "https://en.wikipedia.org/wiki?curid=1304420", "title": "List of Toyota vehicles", "text": "Toyota has produced and marketed vehicles since 1935. Most vehicles sold today are designed and manufactured by Toyota, while some vehicles are produced by other companies and supplied to Toyota through an OEM supply basis. Many models are limited to some regions, while some others are marketed worldwide. This list does not include vehicles marketed under Lexus or Scion marques, or Daihatsu and Hino.\nConcept vehicles.\nThe following is a partial list of concept cars Toyota developed. The year indicates when the vehicle was first officially shown to the public.", "Engineering,_Manufacturing": 0.9990948439, "qwen": "Yes"}
{"id": "1305947", "revid": "46375994", "url": "https://en.wikipedia.org/wiki?curid=1305947", "title": "3D printing", "text": "3D printing or additive manufacturing is the construction of a three-dimensional object from a CAD model or a digital 3D model. It can be done in a variety of processes in which material is deposited, joined or solidified under computer control, with material being added together (such as plastics, liquids or powder grains being fused), typically layer by layer.\nIn the 1980s, 3D printing techniques were considered suitable only for the production of functional or aesthetic prototypes, and a more appropriate term for it at the time was rapid prototyping. , the precision, repeatability, and material range of 3D printing have increased to the point that some 3D printing processes are considered viable as an industrial-production technology, whereby the term \"additive manufacturing\" can be used synonymously with \"3D printing\". One of the key advantages of 3D printing is the ability to produce very complex shapes or geometries that would be otherwise infeasible to construct by hand, including hollow parts or parts with internal truss structures to reduce weight. Fused deposition modeling (FDM), which uses a continuous filament of a thermoplastic material, is the most common 3D printing process in use .\nTerminology.\nThe umbrella term \"additive manufacturing (AM)\" gained popularity in the 2000s, inspired by the theme of material being added together (in any of various ways). In contrast, the term \"subtractive manufacturing\" appeared as a retronym for the large family of machining processes with material \"removal\" as their common process. The term \"3D printing\" still referred only to the polymer technologies in most minds, and the term \"AM\" was more likely to be used in metalworking and end-use part production contexts than among polymer, inkjet, or stereolithography enthusiasts.\nBy the early 2010s, the terms \"3D printing\" and \"additive manufacturing\" evolved senses in which they were alternate umbrella terms for additive technologies, one being used in popular language by consumer-maker communities and the media, and the other used more formally by industrial end-use part producers, machine manufacturers, and global technical standards organizations. Until recently, the term \"3D printing\" has been associated with machines low in price or in capability. \"3D printing\" and \"additive manufacturing\" reflect that the technologies share the theme of material addition or joining throughout a 3D work envelope under automated control. Peter Zelinski, the editor-in-chief of \"Additive Manufacturing\" magazine, pointed out in 2017 that the terms are still often synonymous in casual usage, but some manufacturing industry experts are trying to make a distinction whereby additive manufacturing comprises 3D printing plus other technologies or other aspects of a manufacturing process.\nOther terms that have been used as synonyms or hypernyms have included \"desktop manufacturing\", \"rapid manufacturing\" (as the logical production-level successor to \"rapid prototyping\"), and \"on-demand manufacturing\" (which echoes \"on-demand printing\" in the 2D sense of \"printing\"). The fact that the application of the adjectives \"rapid\" and \"on-demand\" to the noun \"manufacturing\" was novel in the 2000s reveals the long-prevailing mental model of the previous industrial era during which almost all production manufacturing had involved long lead times for laborious tooling development. Today, the term \"subtractive\" has not replaced the term \"machining\", instead complementing it when a term that covers any removal method is needed. Agile tooling is the use of modular means to design tooling that is produced by additive manufacturing or 3D printing methods to enable quick prototyping and responses to tooling and fixture needs. Agile tooling uses a cost-effective and high-quality method to quickly respond to customer and market needs, and it can be used in hydro-forming, stamping, injection molding and other manufacturing processes.\nHistory.\n1940s and 1950s.\nThe general concept of and procedure to be used in 3D-printing was first described by Murray Leinster in his 1945 short story “Things Pass By”: \"But this constructor is both efficient and flexible. I feed magnetronic plastics — the stuff they make houses and ships of nowadays — into this moving arm. It makes drawings in the air following drawings it scans with photo-cells. But plastic comes out of the end of the drawing arm and hardens as it comes ... following drawings only\" \nIt was also described by Raymond F. Jones in his story, \"Tools of the Trade,\" published in the November 1950 issue of \"Astounding Science Fiction\" magazine. He referred to it as a \"molecular spray\" in that story.\n1970s.\nIn 1971, Johannes F Gottwald patented the Liquid Metal Recorder, a continuous inkjet metal material device to form a removable metal fabrication on a reusable surface for immediate use or salvaged for printing again by remelting. This appears to be the first patent describing 3D printing with rapid prototyping and controlled on-demand manufacturing of patterns.\nThe patent states:\nIn 1974, David E. H. Jones laid out the concept of 3D printing in his regular column \"Ariadne\" in the journal \"New Scientist\".\n1980s.\nEarly additive manufacturing equipment and materials were developed in the 1980s.\nIn April 1980, Hideo Kodama of Nagoya Municipal Industrial Research Institute invented two additive methods for fabricating three-dimensional plastic models with photo-hardening thermoset polymer, where the UV exposure area is controlled by a mask pattern or a scanning fiber transmitter.\nHe filed a patent for this XYZ plotter, which was published on 10 November 1981. (JP S56-144478).\nHis research results as journal papers were published in April and November in 1981.\nHowever, there was no reaction to the series of his publications. His device was not highly evaluated in the laboratory and his boss did not show any interest. His research budget was just 60,000 yen or $545 a year. Acquiring the patent rights for the XYZ plotter was abandoned, and the project was terminated.\nA US 4323756 patent, \"method of fabricating articles by sequential deposition\", granted on 6 April 1982 to Raytheon Technologies Corp describes using hundreds or thousands of \"layers\" of powdered metal and a laser energy source and represents an early reference to forming \"layers\" and the fabrication of articles on a substrate.\nOn 2 July 1984, American entrepreneur Bill Masters filed a patent for his computer automated manufacturing process and system (US 4665492). This filing is on record at the USPTO as the first 3D printing patent in history; it was the first of three patents belonging to Masters that laid the foundation for the 3D printing systems used today.\nOn 16 July 1984, Alain Le Méhauté, Olivier de Witte, and Jean Claude André filed their patent for the stereolithography process. The application of the French inventors was abandoned by the French General Electric Company (now Alcatel-Alsthom) and CILAS (The Laser Consortium). The claimed reason was \"for lack of business perspective\".\nIn 1983, Robert Howard started R.H. Research, later named Howtek, Inc. in Feb 1984 to develop a color inkjet 2D printer, Pixelmaster, commercialized in 1986, using Thermoplastic (hot-melt) plastic ink. A team was put together, 6 members from Exxon Office Systems, Danbury Systems Division, an inkjet printer startup and some members of Howtek, Inc group who became popular figures in the 3D printing industry. One Howtek member, Richard Helinski (patent US5136515A, Method and Means for constructing three-dimensional articles by particle deposition, application 11/07/1989 granted 8/04/1992) formed a New Hampshire company C.A.D-Cast, Inc, name later changed to Visual Impact Corporation (VIC) on 8/22/1991. A prototype of the VIC 3D printer for this company is available with a video presentation showing a 3D model printed with a single nozzle inkjet. Another employee Herbert Menhennett formed a New Hampshire company HM Research in 1991 and introduced the Howtek, Inc, inkjet technology and thermoplastic materials to Royden Sanders of SDI and Bill Masters of Ballistic Particle Manufacturing (BPM) where he worked for a number of years. Both BPM 3D printers and SPI 3D printers use Howtek, Inc style Inkjets and Howtek, Inc style materials. Royden Sanders licensed the Helinksi patent prior to manufacturing the Modelmaker 6 Pro at Sanders prototype, Inc (SPI) in 1993. James K. McMahon who was hired by Howtek, Inc to help develop the inkjet, later worked at Sanders Prototype and now operates Layer Grown Model Technology, a 3D service provider specializing in Howtek single nozzle inkjet and SDI printer support. James K. McMahon worked with Steven Zoltan, 1972 drop-on-demand inkjet inventor, at Exxon and has a patent in 1978 that expanded the understanding of the single nozzle design inkjets (Alpha jets) and help perfect the Howtek, Inc hot-melt inkjets. This Howtek hot-melt thermoplastic technology is popular with metal investment casting, especially in the 3D printing jewelry industry. Sanders (SDI) first Modelmaker 6Pro customer was Hitchner Corporations, Metal Casting Technology, Inc in Milford, NH a mile from the SDI facility in late 1993-1995 casting golf clubs and auto engine parts.\nOn 8 August 1984 a patent, US4575330, assigned to UVP, Inc., later assigned to Chuck Hull of 3D Systems Corporation was filed, his own patent for a stereolithography fabrication system, in which individual laminae or layers are added by curing photopolymers with impinging radiation, particle bombardment, chemical reaction or just ultraviolet light lasers. Hull defined the process as a \"system for generating three-dimensional objects by creating a cross-sectional pattern of the object to be formed\". Hull's contribution was the STL (Stereolithography) file format and the digital slicing and infill strategies common to many processes today. In 1986, Charles \"Chuck\" Hull was granted a patent for this system, and his company, 3D Systems Corporation was formed and it released the first commercial 3D printer, the SLA-1, later in 1987 or 1988.\nThe technology used by most 3D printers to date—especially hobbyist and consumer-oriented models—is fused deposition modeling, a special application of plastic extrusion, developed in 1988 by S. Scott Crump and commercialized by his company Stratasys, which marketed its first FDM machine in 1992.\nOwning a 3D printer in the 1980s cost upwards of $300,000 ($650,000 in 2016 dollars).\n1990s.\nAM processes for metal sintering or melting (such as selective laser sintering, direct metal laser sintering, and selective laser melting) usually went by their own individual names in the 1980s and 1990s. At the time, all metalworking was done by processes that are now called non-additive (casting, fabrication, stamping, and machining); although plenty of automation was applied to those technologies (such as by robot welding and CNC), the idea of a tool or head moving through a 3D work envelope transforming a mass of raw material into a desired shape with a toolpath was associated in metalworking only with processes that removed metal (rather than adding it), such as CNC milling, CNC EDM, and many others. But the automated techniques that \"added\" metal, which would later be called additive manufacturing, were beginning to challenge that assumption. By the mid-1990s, new techniques for material deposition were developed at Stanford and Carnegie Mellon University, including microcasting and sprayed materials. Sacrificial and support materials had also become more common, enabling new object geometries.\nThe term \"3D printing\" originally referred to a powder bed process employing standard and custom inkjet print heads, developed at MIT by Emanuel Sachs in 1993 and commercialized by Soligen Technologies, Extrude Hone Corporation, and Z Corporation.\nThe year 1993 also saw the start of an inkjet 3D printer company initially named Sanders Prototype, Inc and later named Solidscape, introducing a high-precision polymer jet fabrication system with soluble support structures, (categorized as a \"dot-on-dot\" technique).\nIn 1995 the Fraunhofer Society developed the selective laser melting process.\n2000s.\nThe Fused Deposition Modeling (FDM) printing process patents expired in 2009. This opened the door for a new wave of companies, many born from the RepRap community, to start developing commercial FDM 3D printers.\n2010s.\nAs the various additive processes matured, it became clear that soon metal removal would no longer be the only metalworking process done through a tool or head moving through a 3D work envelope, transforming a mass of raw material into a desired shape layer by layer. The 2010s were the first decade in which metal end use parts such as engine brackets and large nuts would be grown (either before or instead of machining) in job production rather than obligately being machined from bar stock or plate. It is still the case that casting, fabrication, stamping, and machining are more prevalent than additive manufacturing in metalworking, but AM is now beginning to make significant inroads, and with the advantages of design for additive manufacturing, it is clear to engineers that much more is to come.\nOne place that AM is making a significant inroad is in the aviation industry. With nearly 3.8 billion air travelers in 2016, the demand for fuel efficient and easily produced jet engines has never been higher. For large OEMs (original equipment manufacturers) like Pratt and Whitney (PW) and General Electric (GE) this means looking towards AM as a way to reduce cost, reduce the number of nonconforming parts, reduce weight in the engines to increase fuel efficiency and find new, highly complex shapes that would not be feasible with the antiquated manufacturing methods. One example of AM integration with aerospace was in 2016 when Airbus was delivered the first of GE's LEAP engines. This engine has integrated 3D printed fuel nozzles giving them a reduction in parts from 20 to 1, a 25% weight reduction and reduced assembly times. A fuel nozzle is the perfect in road for additive manufacturing in a jet engine since it allows for optimized design of the complex internals and it is a low stress, non-rotating part. Similarly, in 2015, PW delivered their first AM parts in the PurePower PW1500G to Bombardier. Sticking to low stress, non-rotating parts, PW selected the compressor stators and synch ring brackets to roll out this new manufacturing technology for the first time. While AM is still playing a small role in the total number of parts in the jet engine manufacturing process, the return on investment can already be seen by the reduction in parts, the rapid production capabilities and the \"optimized design in terms of performance and cost\".\nAs technology matured, several authors had begun to speculate that 3D printing could aid in sustainable development in the developing world.\nIn 2012, Filabot developed a system for closing the loop with plastic and allows for any FDM or FFF 3D printer to be able to print with a wider range of plastics.\nIn 2014, Benjamin S. Cook and Manos M. Tentzeris demonstrate the first multi-material, vertically integrated printed electronics additive manufacturing platform (VIPRE) which enabled 3D printing of functional electronics operating up to 40 GHz.\nAs the price of printers started to drop people interested in this technology had more access and freedom to make what they wanted. As of 2014 the price for commercial printers was still high with the cost being over $2,000.\nThe term \"3D printing\" originally referred to a process that deposits a binder material onto a powder bed with inkjet printer heads layer by layer. More recently, the popular vernacular has started using the term to encompass a wider variety of additive-manufacturing techniques such as electron-beam additive manufacturing and selective laser melting. The United States and global technical standards use the official term \"additive manufacturing\" for this broader sense.\nThe most-commonly used 3D printing process (46% ) is a material extrusion technique called fused deposition modeling, or FDM. While FDM technology was invented after the other two most popular technologies, stereolithography (SLA) and selective laser sintering (SLS), FDM is typically the most inexpensive of the three by a large margin, which lends to the popularity of the process.\n2020s.\nAs of 2020, 3D printers have reached the level of quality and price that allows most people to enter the world of 3D printing. In 2020 decent quality printers can be found for less than US$200 for entry level machines. These more affordable printers are usually fused deposition modeling (FDM) printers.\nIn November 2021 a British patient named Steve Verze received the world's first fully 3D-printed prosthetic eye from the Moorfields Eye Hospital in London.\nBenefits of 3D printing.\nAdditive manufacturing or 3D printing has rapidly gained importance in the field of engineering due to its many benefits. Some of these benefits include enabling faster prototyping, reducing manufacturing costs, increasing product customization, and improving product quality.\nFurthermore, the capabilities of 3D printing have extended beyond traditional manufacturing, with applications in renewable energy systems. 3D printing technology can be used to produce battery energy storage systems, which are essential for sustainable energy generation and distribution.\nAnother benefit of 3D printing is the technology's ability to produce complex geometries with high precision and accuracy. This is particularly relevant in the field of microwave engineering, where 3D printing can be used to produce components with unique properties that are difficult to achieve using traditional manufacturing methods.\nGeneral principles.\nModeling.\n3D printable models may be created with a computer-aided design (CAD) package, via a 3D scanner, or by a plain digital camera and photogrammetry software. 3D printed models created with CAD result in relatively fewer errors than other methods. Errors in 3D printable models can be identified and corrected before printing. The manual modeling process of preparing geometric data for 3D computer graphics is similar to plastic arts such as sculpting. 3D scanning is a process of collecting digital data on the shape and appearance of a real object, creating a digital model based on it.\nCAD models can be saved in the stereolithography file format (STL), a de facto CAD file format for additive manufacturing that stores data based on triangulations of the surface of CAD models. STL is not tailored for additive manufacturing because it generates large file sizes of topology optimized parts and lattice structures due to the large number of surfaces involved. A newer CAD file format, the Additive Manufacturing File format (AMF) was introduced in 2011 to solve this problem. It stores information using curved triangulations.\nPrinting.\nBefore printing a 3D model from an STL file, it must first be examined for errors. Most CAD applications produce errors in output STL files, of the following types:\nA step in the STL generation known as \"repair\" fixes such problems in the original model. Generally STLs that have been produced from a model obtained through 3D scanning often have more of these errors as 3D scanning is often achieved by point to point acquisition/mapping. 3D reconstruction often includes errors.\nOnce completed, the STL file needs to be processed by a piece of software called a \"slicer\", which converts the model into a series of thin layers and produces a G-code file containing instructions tailored to a specific type of 3D printer (FDM printers). This G-code file can then be printed with 3D printing client software (which loads the G-code, and uses it to instruct the 3D printer during the 3D printing process).\nPrinter resolution describes layer thickness and X–Y resolution in dots per inch (dpi) or micrometers (μm). Typical layer thickness is around , although some machines can print layers as thin as . X–Y resolution is comparable to that of laser printers. The particles (3D dots) are around in diameter. For that printer resolution, specifying a mesh resolution of and a chord length generates an optimal STL output file for a given model input file. Specifying higher resolution results in larger files without increase in print quality.\nConstruction of a model with contemporary methods can take anywhere from several hours to several days, depending on the method used and the size and complexity of the model. Additive systems can typically reduce this time to a few hours, although it varies widely depending on the type of machine used and the size and number of models being produced simultaneously.\nFinishing.\nThough the printer-produced resolution and surface finish are sufficient for some applications, post-processing and finishing methods allow for benefits such as greater dimensional accuracy, smoother surfaces, other modifications such as coloration.\nSurface finish of a 3D printed part can improved using subtractive methods such as sanding and bead blasting. When smoothing parts that require dimensional accuracy, it is important to take into account the volume of the material being removed.\nSome printable polymers, such as acrylonitrile butadiene styrene (ABS), allow the surface finish to be smoothed and improved using chemical vapor processes based on acetone or similar solvents.\nSome additive manufacturing techniques can benefit from annealing annealing as a post-processing step. Annealing a 3D printed part allows for better internal layer bonding due to recrystalization of the part and allows for an increase in mechanical properties, some of which are fracture toughness, flexural strength, impact resistance, and heat resistance. Annealing a component may not be suitable for applications where dimensional accuracy is required, as it can introduce warpage or shrinkage due to heating and cooling.\nAdditive/Subtractive Hybrid Manufacturing (ASHM) is a method that involves producing a 3D printed part and using machining (subtractive manufacturing) to remove material. Machining operations can be completed after each layer, or after the entire 3D print has been completed depending on the application requirements. These hybrid methods allow for 3D printed parts to achieve better surface finishes and dimensional accuracy.\nThe layered structure of traditional additive manufacturing processes leads to a stair-stepping effect on part surfaces which are curved or tilted in respect to the building platform. The effect strongly depends on the layer height used, as well as the orientation of a part surface inside the building process. This effect can be minimized using \"variable layer heights\" or \"adaptive layer heights\". These methods decreased the layer height in places where higher quality is needed.\nPainting a 3D printed part offers a range of finishes and appearances that may not be achievable through most 3D printing techniques. The process typically involves several steps such as surface preparation, priming, and painting. These steps help prepare the surface of the part and ensuring the paint adheres properly.\nSome additive manufacturing techniques are capable of using multiple materials simultaneously. These techniques are able to print in multiple colors and color combinations simultaneously, and can produce parts that may not necessarily require painting.\nSome printing techniques require internal supports to be built to support overhanging features during construction. These supports must be mechanically removed or dissolved if using a water-soluble support material such as PVA using after completing a print.\nSome commercial metal 3D printers involve cutting the metal component off the metal substrate after deposition. A new process for the GMAW 3D printing allows for substrate surface modifications to remove aluminium or steel.\nMaterials.\nTraditionally, 3D printing focused on polymers for printing, due to the ease of manufacturing and handling polymeric materials. However, the method has rapidly evolved to not only print various polymers but also metals and ceramics, making 3D printing a versatile option for manufacturing. Layer-by-layer fabrication of three-dimensional physical models is a modern concept that \"stems from the ever-growing CAD industry, more specifically the solid modeling side of CAD. Before solid modeling was introduced in the late 1980s, three-dimensional models were created with wire frames and surfaces.\" but in all cases the layers of materials are controlled by the printer and the material properties. The three-dimensional material layer is controlled by deposition rate as set by the printer operator and stored in a computer file. The earliest printed patented material was a Hot melt type ink for printing patterns using a heated metal alloy. See 1970s history above.\nCharles Hull filed the first patent on August 8, 1984, to use a UV-cured acrylic resin using a UV masked light source at UVP Corp to build a simple model. The SLA-1 was the first SL product announced by 3D Systems at Autofact Exposition, Detroit, November 1978 in Detroit. The SLA-1 Beta shipped in Jan 1988 to Baxter Healthcare, Pratt and Whitney, General Motors and AMP. The first production SLA-1 shipped to Precision Castparts in April 1988. The UV resin material changed over quickly to an epoxy-based material resin. In both cases, SLA-1 models needed UV oven curing after being rinsed in a solvent cleaner to remove uncured boundary resin. A Post Cure Apparatus (PCA) was sold with all systems. The early resin printers required a blade to move fresh resin over the model on each layer. The layer thickness was 0.006 inches and the HeCd Laser model of the SLA-1 was 12 watts and swept across the surface at 30 in per second. UVP was acquired by 3D Systems in Jan 1990.\nA review in the history shows a number of materials (resins, plastic powder, plastic filament and hot-melt plastic ink) were used in the 1980s for patents in the rapid prototyping field. Masked lamp UV-cured resin was also introduced by Cubital's Itzchak Pomerantz in the Soldier 5600, Carl Deckard's (DTM) laser sintered thermoplastic powders, and adhesive-laser cut paper (LOM) stacked to form objects by Michael Feygin before 3D Systems made its first announcement. Scott Crump was also working with extruded \"melted\" plastic filament modeling (FDM) and Drop deposition had been patented by William E Masters a week after Charles Hull's patent in 1984, but he had to discover Thermoplastic Inkjets introduced by Visual Impact Corporation 3D printer in 1992 using inkjets from Howtek, Inc., before he formed BPM to bring out his own 3D printer product in 1994.\nMulti-material 3D printing.\nEfforts to achieve multi-material 3D printing range from enhanced FDM-like processes like VoxelJet, to novel voxel-based printing technologies like layered assembly.\nA drawback of many existing 3D printing technologies is that they only allow one material to be printed at a time, limiting many potential applications which require the integration of different materials in the same object. Multi-material 3D printing solves this problem by allowing objects of complex and heterogeneous arrangements of materials to be manufactured using a single printer. Here, a material must be specified for each voxel (or 3D printing pixel element) inside the final object volume.\nThe process can be fraught with complications, however, due to the isolated and monolithic algorithms. Some commercial devices have sought to solve these issues, such as building a Spec2Fab translator, but the progress is still very limited. Nonetheless, in the medical industry, a concept of 3D printed pills and vaccines has been presented.\nWith this new concept, multiple medications can be combined, which will decrease many risks. With more and more applications of multi-material 3D printing, the costs of daily life and high technology development will become inevitably lower.\nMetallographic materials of 3D printing is also being researched. By classifying each material, CIMP-3D can systematically perform 3D printing with multiple materials.\n4D printing.\nUsing 3D printing and multi-material structures in additive manufacturing has allowed for the design and creation of what is called 4D printing. 4D printing is an additive manufacturing process in which the printed object changes shape with time, temperature, or some other type of stimulation. 4D printing allows for the creation of dynamic structures with adjustable shapes, properties or functionality. The smart/stimulus responsive materials that are created using 4D printing can be activated to create calculated responses such as self-assembly, self-repair, multi-functionality, reconfiguration and shape shifting. This allows for customized printing of shape changing and shape-memory materials.\n4D printing has the potential to find new applications and uses for materials (plastics, composites, metals, etc.) and will create new alloys and composites that were not viable before. The versatility of this technology and materials can lead to advances in multiple fields of industry, including space, commercial and the medical field. The repeatability, precision, and material range for 4D printing must increase to allow the process to become more practical throughout these industries. \nTo become a viable industrial production option, there are a couple of challenges that 4D printing must overcome. The challenges of 4D printing include the fact that the microstructures of these printed smart materials must be close to or better than the parts obtained through traditional machining processes. New and customizable materials need to be developed that have the ability to consistently respond to varying external stimuli and change to their desired shape. There is also a need to design new software for the various technique types of 4D printing. The 4D printing software will need to take into consideration the base smart material, printing technique, and structural and geometric requirements of the design.\nProcesses and printers.\nISO/ASTM52900-15 defines seven categories of additive manufacturing (AM) processes within its meaning. They are:\nThe main differences between processes are in the way layers are deposited to create parts and in the materials that are used. Each method has its own advantages and drawbacks, which is why some companies offer a choice of powder and polymer for the material used to build the object. Others sometimes use standard, off-the-shelf business paper as the build material to produce a durable prototype. The main considerations in choosing a machine are generally speed, costs of the 3D printer, of the printed prototype, choice and cost of the materials, and color capabilities. Printers that work directly with metals are generally expensive. However less expensive printers can be used to make a mold, which is then used to make metal parts.\nMaterial Jetting.\nThe first process where three-dimensional material is deposited to form an object was done with material jetting or as it was originally called particle deposition. Particle deposition by inkjet first started with continuous inkjet technology (CIT) (1950s) and later with drop-on-demand inkjet technology (1970s) using hot-melt inks. Wax inks were the first three-dimensional materials jetted and later low temperature alloy metal was jetted with CIT. Wax and thermoplastic hot-melts were jetted next by DOD. Objects were very small and started with text characters and numerals for signage. An object must have form and can be handled. Wax characters tumbled off paper documents and inspired a liquid metal recorder patent to make metal characters for signage in 1971. Thermoplastic color inks (CMYK) printed with layers of each color to form the first digitally formed layered objects in 1984. The idea of investment casting with Solid-Ink jetted images or patterns in 1984 led to the first patent to form articles from particle deposition in 1989, issued in 1992.\nMaterial Extrusion.\nSome methods melt or soften the material to produce the layers. In fused filament fabrication, also known as fused deposition modeling (FDM), the model or part is produced by extruding small beads or streams of material which harden immediately to form layers. A filament of thermoplastic, metal wire, or other material is fed into an extrusion nozzle head (3D printer extruder), which heats the material and turns the flow on and off. FDM is somewhat restricted in the variation of shapes that may be fabricated. Another technique fuses parts of the layer and then moves upward in the working area, adding another layer of granules and repeating the process until the piece has built up. This process uses the unfused media to support overhangs and thin walls in the part being produced, which reduces the need for temporary auxiliary supports for the piece. Recently, FFF/FDM has expanded to 3-D print directly from pellets to avoid the conversion to filament. This process is called fused particle fabrication (FPF) (or fused granular fabrication (FGF) and has the potential to use more recycled materials.\nPowder Bed Fusion.\nPowder Bed Fusion techniques, or PBF, include several processes such as DMLS, SLS, SLM, MJF and EBM. Powder Bed Fusion processes can be used with an array of materials and their flexibility allows for geometrically complex structures, making it a go to choice for many 3D printing projects. These techniques include selective laser sintering, with both metals and polymers, and direct metal laser sintering. Selective laser melting does not use sintering for the fusion of powder granules but will completely melt the powder using a high-energy laser to create fully dense materials in a layer-wise method that has mechanical properties similar to those of conventional manufactured metals. Electron beam melting is a similar type of additive manufacturing technology for metal parts (e.g. titanium alloys). EBM manufactures parts by melting metal powder layer by layer with an electron beam in a high vacuum. Another method consists of an inkjet 3D printing system, which creates the model one layer at a time by spreading a layer of powder (plaster, or resins) and printing a binder in the cross-section of the part using an inkjet-like process. With laminated object manufacturing, thin layers are cut to shape and joined. In addition to the previously mentioned methods, HP has developed the Multi Jet Fusion (MJF) which is a powder base technique, though no lasers are involved. An inkjet array applies fusing and detailing agents which are then combined by heating to create a solid layer.\nBinder jetting.\nThe binder jetting 3D printing technique is the deposition of a binding adhesive agent onto layers of material, usually powdered. The materials can be ceramic-based or metal. This method is also known as inkjet 3D printing system. To produce the piece, the printer builds the model using a head that moves over the platform base and deposits, one layer at a time, by spreading a layer of powder (plaster, or resins) and printing a binder in the cross-section of the part using an inkjet-like process. This is repeated until every layer has been printed. This technology allows the printing of full color prototypes, overhangs, and elastomer parts. The strength of bonded powder prints can be enhanced with wax or thermoset polymer impregnation.\nStereolithography.\nOther methods cure liquid materials using different sophisticated technologies, such as stereolithography. Photopolymerization is primarily used in stereolithography to produce a solid part from a liquid. Inkjet printer systems like the \"Objet PolyJet\" system spray photopolymer materials onto a build tray in ultra-thin layers (between 16 and 30 μm) until the part is completed. Each photopolymer layer is cured with UV light after it is jetted, producing fully cured models that can be handled and used immediately, without post-curing. Ultra-small features can be made with the 3D micro-fabrication technique used in multiphoton photopolymerisation. Due to the nonlinear nature of photo excitation, the gel is cured to a solid only in the places where the laser was focused while the remaining gel is then washed away. Feature sizes of under 100 nm are easily produced, as well as complex structures with moving and interlocked parts. Yet another approach uses a synthetic resin that is solidified using LEDs.\nIn Mask-image-projection-based stereolithography, a 3D digital model is sliced by a set of horizontal planes. Each slice is converted into a two-dimensional mask image. The mask image is then projected onto a photocurable liquid resin surface and light is projected onto the resin to cure it in the shape of the layer. Continuous liquid interface production begins with a pool of liquid photopolymer resin. Part of the pool bottom is transparent to ultraviolet light (the \"window\"), which causes the resin to solidify. The object rises slowly enough to allow resin to flow under and maintain contact with the bottom of the object. In powder-fed directed-energy deposition, a high-power laser is used to melt metal powder supplied to the focus of the laser beam. The powder fed directed energy process is similar to Selective Laser Sintering, but the metal powder is applied only where material is being added to the part at that moment.\nComputed Axial Lithography.\nComputed axial lithography is a method for 3D printing based on computerised tomography scans to create prints in photo-curable resin. It was developed by a collaboration between the University of California, Berkeley with Lawrence Livermore National Laboratory. Unlike other methods of 3D printing it does not build models through depositing layers of material like fused deposition modelling and stereolithography, instead it creates objects using a series of 2D images projected onto a cylinder of resin. It is notable for its ability to build an object much more quickly than other methods using resins and the ability to embed objects within the prints.\nLiquid Additive Manufacturing.\nLiquid additive manufacturing (LAM) is a 3D printing technique which deposits a liquid or high viscose material (e.g. liquid silicone rubber) onto a build surface to create an object which then is vulcanised using heat to harden the object. The process was originally created by Adrian Bowyer and was then built upon by German RepRap.\nA technique called programmable tooling uses 3D printing to create a temporary mold, which is then filled via a conventional injection molding process and then immediately dissolved.\nLamination.\nIn some printers, paper can be used as the build material, resulting in a lower cost to print. During the 1990s some companies marketed printers that cut cross-sections out of special adhesive coated paper using a carbon dioxide laser and then laminated them together.\nIn 2005 Mcor Technologies Ltd developed a different process using ordinary sheets of office paper, a tungsten carbide blade to cut the shape, and selective deposition of adhesive and pressure to bond the prototype.\nDirected Energy Deposition (DED).\nPowder-fed directed-energy deposition.\nIn powder-fed directed-energy deposition, a high-power laser is used to melt metal powder supplied to the focus of the laser beam. The laser beam typically travels through the center of the deposition head and is focused to a small spot by one or more lenses. The build occurs on an X-Y table which is driven by a tool path created from a digital model to fabricate an object layer by layer. The deposition head is moved up vertically as each layer is completed. Some systems even make use of 5-axis or 6-axis systems (\"i.e.\" articulated arms) capable of delivering material on the substrate (a printing bed, or a pre-existing part) with few to no spatial access restrictions. Metal powder is delivered and distributed around the circumference of the head or can be split by an internal manifold and delivered through nozzles arranged in various configurations around the deposition head. A hermetically sealed chamber filled with inert gas or a local inert shroud gas (sometimes both combined) are often used to shield the melt pool from atmospheric oxygen, to limit oxidation and better control the material properties. The powder-fed directed-energy process is similar to Selective Laser Sintering, but the metal powder is projected only where material is being added to the part at that moment. The laser beam is used to heat up and create a \"melt pool\" on the substrate, in which the new powder is injected quasi-simultaneously. The process supports a wide range of materials including titanium, stainless steel, aluminium, tungsten, and other specialty materials as well as composites and functionally graded material. The process can not only fully build new metal parts but can also add material to existing parts for example for coatings, repair, and hybrid manufacturing applications. Laser engineered net shaping (LENS), which was developed by Sandia National Labs, is one example of the powder-fed directed-energy deposition process for 3D printing or restoring metal parts.\nMetal wire processes.\nLaser-based wire-feed systems, such as Laser Metal Deposition-wire (LMD-w), feed wire through a nozzle that is melted by a laser using inert gas shielding in either an open environment (gas surrounding the laser), or in a sealed chamber. Electron beam freeform fabrication uses an electron beam heat source inside a vacuum chamber.\nIt is also possible to use conventional gas metal arc welding attached to a 3D stage to 3-D print metals such as steel, bronze and aluminium. Low-cost open source RepRap-style 3-D printers have been outfitted with Arduino-based sensors and demonstrated reasonable metallurgical properties from conventional welding wire as feedstock.\nSelective Powder Deposition (SPD).\nIn selective powder deposition, build and support powders are selectively deposited into a crucible, such that the build powder takes the shape of the desired object and support powder fills the rest of the volume in the crucible. Then an infill material is applied, such that it comes in contact with the build powder. Then the crucible is fired up in a kiln at the temperature above the melting point of the infill, but below the melting points of the powders. When the infill melts, it soaks the build powder. But it doesn't soak the support powder, because the support powder is chosen to be such that it is not wettable by the infill. If at the firing temperature, the atoms of the infill material and the build powder are mutually defusable, such as in case of copper powder and zinc infill, then the resulting material will be a uniform mixture of those atoms, in this case, bronze. But if the atoms are not mutually defusable, such as in case of tungsten and copper at 1100 °C, then the resulting material will be a composite. To prevent shape distortion, the firing temperature must be below the solidus temperature of the resulting alloy.\nCryogenic 3D Printing.\nCryogenic 3D printing is a collection of techniques which forms solid structures by freezing liquid materials while they are deposited. As each liquid layer is applied, it is cooled by the low temperature of the previous layer and printing environment which results in solidification. Unlike other 3D printing techniques, Cryogenic 3D printing requires a controlled printing environment. The ambient temperature must be below the material's freezing point to ensure the structure remains solid during manufacturing and the humidity must remain low to prevent frost formation between the application of layers. Materials typically include water and water-based solutions, such as brine, slurry, and hydrogels. Cryogenic 3D printing techniques include Rapid Freezing Prototype (RFP), Low-Temperature Deposition Manufacturing (LDM), and Freeze-form Extrusion Fabrication (FEF).\nApplications.\n3D printing or additive manufacturing has been used in manufacturing, medical, industry and sociocultural sectors (e.g. Cultural Heritage) to create successful commercial technology. More recently, 3D printing has also been used in the humanitarian and development sector to produce a range of medical items, prosthetics, spares and repairs. The earliest application of additive manufacturing was on the toolroom end of the manufacturing spectrum. For example, rapid prototyping was one of the earliest additive variants, and its mission was to reduce the lead time and cost of developing prototypes of new parts and devices, which was earlier only done with subtractive toolroom methods such as CNC milling, turning, and precision grinding. In the 2010s, additive manufacturing entered production to a much greater extent.\nFood industry.\nAdditive manufacturing of food is being developed by squeezing out food, layer by layer, into three-dimensional objects. A large variety of foods are appropriate candidates, such as chocolate and candy, and flat foods such as crackers, pasta, and pizza. NASA is looking into the technology in order to create 3D printed food to limit food waste and to make food that is designed to fit an astronaut's dietary needs. In 2018, Italian bioengineer Giuseppe Scionti developed a technology allowing the production of fibrous plant-based meat analogues using a custom 3D bioprinter, mimicking meat texture and nutritional values.\nFashion industry.\n3D printing has entered the world of clothing, with fashion designers experimenting with 3D-printed bikinis, shoes, and dresses. In commercial production, Nike used 3D printing to prototype and manufacture the 2012 Vapor Laser Talon football shoe for players of American football, and New Balance has 3D manufactured custom-fit shoes for athletes. 3D printing has come to the point where companies are printing consumer grade eyewear with on-demand custom fit and styling (although they cannot print the lenses). On-demand customization of glasses is possible with rapid prototyping.\nVanessa Friedman, fashion director and chief fashion critic at \"The New York Times\", says 3D printing will have a significant value for fashion companies down the road, especially if it transforms into a print-it-yourself tool for shoppers. \"There's real sense that this is not going to happen anytime soon,\" she says, \"but it will happen, and it will create dramatic change in how we think both about intellectual property and how things are in the supply chain\". She adds: \"Certainly some of the fabrications that brands can use will be dramatically changed by technology.\"\nTransportation industry.\nIn cars, trucks, and aircraft, Additive Manufacturing is beginning to transform both (1) unibody and fuselage design and production and (2) powertrain design and production. For example, General Electric uses high-end 3D printers to build parts for turbines. Many of these systems are used for rapid prototyping, before mass production methods are employed. Other prominent examples include:\nFirearm industry.\nAM's impact on firearms involves two dimensions: new manufacturing methods for established companies, and new possibilities for the making of do-it-yourself firearms. In 2012, the US-based group Defense Distributed disclosed plans to design a working plastic 3D printed firearm \"that could be downloaded and reproduced by anybody with a 3D printer.\" After Defense Distributed released their plans, questions were raised regarding the effects that 3D printing and widespread consumer-level CNC machining may have on gun control effectiveness. Moreover, armour design strategies can be enhanced by taking inspiration from nature and prototyping those designs easily possible using additive manufacturing.\nHealth sector.\nSurgical uses of 3D printing-centric therapies have a history beginning in the mid-1990s with anatomical modeling for bony reconstructive surgery planning. Patient-matched implants were a natural extension of this work, leading to truly personalized implants that fit one unique individual. Virtual planning of surgery and guidance using 3D printed, personalized instruments have been applied to many areas of surgery including total joint replacement and craniomaxillofacial reconstruction with great success. One example of this is the bioresorbable trachial splint to treat newborns with tracheobronchomalacia developed at the University of Michigan. The use of additive manufacturing for serialized production of orthopedic implants (metals) is also increasing due to the ability to efficiently create porous surface structures that facilitate osseointegration. The hearing aid and dental industries are expected to be the biggest area of future development using the custom 3D printing technology.\n3D printing is not just limited to inorganic materials; there have been a number of biomedical advancements made possible by 3D printing. , 3D bio-printing technology has been studied by biotechnology firms and academia for possible use in tissue engineering applications in which organs and body parts are built using inkjet printing techniques. In this process, layers of living cells are deposited onto a gel medium or sugar matrix and slowly built up to form three-dimensional structures including vascular systems. 3D printing has been considered as a method of implanting stem cells capable of generating new tissues and organs in living humans. In 2018, 3D printing technology was used for the first time to create a matrix for cell immobilization in fermentation. Propionic acid production by \"Propionibacterium acidipropionici\" immobilized on 3D-printed nylon beads was chosen as a model study. It was shown that those 3D-printed beads were capable of promoting high density cell attachment and propionic acid production, which could be adapted to other fermentation bioprocesses.\n3D printing has also been employed by researchers in the pharmaceutical field. During the last few years there's been a surge in academic interest regarding drug delivery with the aid of AM techniques. This technology offers a unique way for materials to be utilized in novel formulations. AM manufacturing allows for the usage of materials and compounds in the development of formulations, in ways that are not possible with conventional/traditional techniques in the pharmaceutical field, e.g. tableting, cast-molding, etc. Moreover, one of the major advantages of 3D printing, especially in the case of fused deposition modelling (FDM), is the personalization of the dosage form that can be achieved, thus, targeting the patient's specific needs. In the not-so-distant future, 3D printers are expected to reach hospitals and pharmacies in order to provide on demand production of personalized formulations according to the patients' needs.\nMedical equipment.\nDuring the COVID-19 pandemic 3d printers were used to supplement the strained supply of PPE through volunteers using their personally owned printers to produce various pieces of personal protective equipment (i.e. frames for face shields).\nEducation sector.\n3D printing, and open source 3D printers in particular, are the latest technology making inroads into the classroom. Higher education has proven to be a major buyer of desktop and professional 3D printers which industry experts generally view as a positive indicator. Some authors have claimed that 3D printers offer an unprecedented \"revolution\" in STEM education. The evidence for such claims comes from both the low-cost ability for rapid prototyping in the classroom by students, but also the fabrication of low-cost high-quality scientific equipment from open hardware designs forming open-source labs. Additionally, Libraries around the world have also become locations to house smaller 3D printers for educational and community access. Future applications for 3D printing might include creating open-source scientific equipment.\nReplicating archeological artifacts.\nIn the 2010s, 3D printing became intensively used in the cultural heritage field for preservation, restoration and dissemination purposes. Many Europeans and North American Museums have purchased 3D printers and actively recreate missing pieces of their relics and archaeological monuments such as Tiwanaku in Bolivia. The Metropolitan Museum of Art and the British Museum have started using their 3D printers to create museum souvenirs that are available in the museum shops. Other museums, like the National Museum of Military History and Varna Historical Museum, have gone further and sell through the online platform Threeding digital models of their artifacts, created using Artec 3D scanners, in 3D printing friendly file format, which everyone can 3D print at home.\nReplicating historic buildings.\nThe application of 3D printing for the representation of architectural assets has many challenges. In 2018, the structure of Iran National Bank was traditionally surveyed and modeled in computer graphics software (specifically, Cinema4D) and was optimized for 3D printing. The team tested the technique for the construction of the part and it was successful. After testing the procedure, the modellers reconstructed the structure in Cinema4D and exported the front part of the model to Netfabb. The entrance of the building was chosen due to the 3D printing limitations and the budget of the project for producing the maquette. 3D printing was only one of the capabilities enabled by the produced 3D model of the bank, but due to the project's limited scope, the team did not continue modelling for the virtual representation or other applications. In 2021, Parsinejad et al. comprehensively compared the hand surveying method for 3D reconstruction ready for 3D printing with digital recording (adoption of photogrammetry method).\nSoft actuators.\n3D printed soft actuators is a growing application of 3D printing technology which has found its place in the 3D printing applications. These soft actuators are being developed to deal with soft structures and organs especially in biomedical sectors and where the interaction between human and robot is inevitable. The majority of the existing soft actuators are fabricated by conventional methods that require manual fabrication of devices, post processing/assembly, and lengthy iterations until maturity of the fabrication is achieved. Instead of the tedious and time-consuming aspects of the current fabrication processes, researchers are exploring an appropriate manufacturing approach for effective fabrication of soft actuators. Thus, 3D printed soft actuators are introduced to revolutionize the design and fabrication of soft actuators with custom geometrical, functional, and control properties in a faster and inexpensive approach. They also enable incorporation of all actuator components into a single structure eliminating the need to use external joints, adhesives, and fasteners.\nCircuit boards.\nCircuit board manufacturing involves multiple steps which include imaging, drilling, plating, soldermask coating, nomenclature printing and surface finishes. These steps include many chemicals such as harsh solvents and acids. 3D printing circuit boards remove the need for many of these steps while still producing complex designs. Polymer ink is used to create the layers of the build while silver polymer is used for creating the traces and holes used to allow electricity to flow. Current circuit board manufacturing can be a tedious process depending on the design. Specified materials are gathered and sent into inner layer processing where images are printed, developed and etched. The etches cores are typically punched to add lamination tooling. The cores are then prepared for lamination. The stack-up, the buildup of a circuit board, is built and sent into lamination where the layers are bonded. The boards are then measured and drilled. Many steps may differ from this stage however for simple designs, the material goes through a plating process to plate the holes and surface. The outer image is then printed, developed and etched. After the image is defined, the material must get coated with soldermask for later soldering. Nomenclature is then added so components can be identified later. Then the surface finish is added. The boards are routed out of panel form into their singular or array form and then electrically tested. Aside from the paperwork which must be completed which proves the boards meet specifications, the boards are then packed and shipped. The benefits of 3D printing would be that the final outline is defined from the beginning, no imaging, punching or lamination is required and electrical connections are made with the silver polymer which eliminates drilling and plating. The final paperwork would also be greatly reduced due to the lack of materials required to build the circuit board. Complex designs which may take weeks to complete through normal processing can be 3D printed, greatly reducing manufacturing time.\nHobbyists.\nIn 2005, academic journals had begun to report on the possible artistic applications of 3D printing technology. Off the shelf machines were increasingly capable of producing practical household applications, for example, ornamental objects. Some practical examples include a working clock and gears printed for home woodworking machines among other purposes. Web sites associated with home 3D printing tended to include backscratchers, coat hooks, door knobs, etc. As of 2017, domestic 3D printing was reaching a consumer audience beyond hobbyists and enthusiasts. Several projects and companies are making efforts to develop affordable 3D printers for home desktop use. Much of this work has been driven by and targeted at DIY/maker/enthusiast/early adopter communities, with additional ties to the academic and hacker communities.\nSped on by decreases in price and increases in quality, an estimated 2 million people worldwide have purchased a 3D printer for hobby use.\nLegal aspects.\nIntellectual property.\n3D printing has existed for decades within certain manufacturing industries where many legal regimes, including patents, industrial design rights, copyrights, and trademarks may apply. However, there is not much jurisprudence to say how these laws will apply if 3D printers become mainstream and individuals or hobbyist communities begin manufacturing items for personal use, for non-profit distribution, or for sale.\nAny of the mentioned legal regimes may prohibit the distribution of the designs used in 3D printing, or the distribution or sale of the printed item. To be allowed to do these things, where an active intellectual property was involved, a person would have to contact the owner and ask for a licence, which may come with conditions and a price. However, many patent, design and copyright laws contain a standard limitation or exception for \"private\", \"non-commercial\" use of inventions, designs or works of art protected under intellectual property (IP). That standard limitation or exception may leave such private, non-commercial uses outside the scope of IP rights.\nPatents cover inventions including processes, machines, manufacturing, and compositions of matter and have a finite duration which varies between countries, but generally 20 years from the date of application. Therefore, if a type of wheel is patented, printing, using, or selling such a wheel could be an infringement of the patent.\nCopyright covers an expression in a tangible, fixed medium and often lasts for the life of the author plus 70 years thereafter. For example, a sculptor retains copyright over a statue, such that other people cannot then legally distribute designs to print an identical or similar statue without paying royalties, waiting for the copyright to expire, or working within a fair use exception.\nWhen a feature has both artistic (copyrightable) and functional (patentable) merits, when the question has appeared in US court, the courts have often held the feature is not copyrightable unless it can be separated from the functional aspects of the item. In other countries the law and the courts may apply a different approach allowing, for example, the design of a useful device to be registered (as a whole) as an industrial design on the understanding that, in case of unauthorized copying, only the non-functional features may be claimed under design law whereas any technical features could only be claimed if covered by a valid patent.\nGun legislation and administration.\nThe US Department of Homeland Security and the Joint Regional Intelligence Center released a memo stating that \"significant advances in three-dimensional (3D) printing capabilities, availability of free digital 3D printable files for firearms components, and difficulty regulating file sharing may present public safety risks from unqualified gun seekers who obtain or manufacture 3D printed guns\" and that \"proposed legislation to ban 3D printing of weapons may deter, but cannot completely prevent, their production. Even if the practice is prohibited by new legislation, online distribution of these 3D printable files will be as difficult to control as any other illegally traded music, movie or software files.\"\nAttempting to restrict the distribution of gun plans via the Internet has been likened to the futility of preventing the widespread distribution of DeCSS, which enabled DVD ripping. After the US government had Defense Distributed take down the plans, they were still widely available via the Pirate Bay and other file sharing sites. Downloads of the plans from the UK, Germany, Spain, and Brazil were heavy. Some US legislators have proposed regulations on 3D printers to prevent them from being used for printing guns. 3D printing advocates have suggested that such regulations would be futile, could cripple the 3D printing industry, and could infringe on free speech rights, with early pioneer of 3D printing professor Hod Lipson suggesting that gunpowder could be controlled instead.\nInternationally, where gun controls are generally stricter than in the United States, some commentators have said the impact may be more strongly felt since alternative firearms are not as easily obtainable. Officials in the United Kingdom have noted that producing a 3D printed gun would be illegal under their gun control laws. Europol stated that criminals have access to other sources of weapons but noted that as technology improves, the risks of an effect would increase.\nAerospace regulation.\nIn the United States, the FAA has anticipated a desire to use additive manufacturing techniques and has been considering how best to regulate this process. The FAA has jurisdiction over such fabrication because all aircraft parts must be made under FAA production approval or under other FAA regulatory categories. In December 2016, the FAA approved the production of a 3D printed fuel nozzle for the GE LEAP engine. Aviation attorney Jason Dickstein has suggested that additive manufacturing is merely a production method, and should be regulated like any other production method. He has suggested that the FAA's focus should be on guidance to explain compliance, rather than on changing the existing rules, and that existing regulations and guidance permit a company \"to develop a robust quality system that adequately reflects regulatory needs for quality assurance\".\nHealth and safety.\nResearch on the health and safety concerns of 3D printing is new and in development due to the recent proliferation of 3D printing devices. In 2017, the European Agency for Safety and Health at Work has published a discussion paper on the processes and materials involved in 3D printing, potential implications of this technology for occupational safety and health and avenues for controlling potential hazards.\nNoise levels.\nNoise level is measured in decibels (dB), and can vary greatly in home-printers from 15 dB to 75 dB. Some main sources of noise in filament printers are fans, motors and bearings, while in resin printers the fans usually are responsible for most of the noise. Some methods for dampening the noise from a printer may be to install vibration isolation, use larger diameter fans, perform regular maintenance and lubrication, or using a soundproofing enclosure.\nImpact.\nAdditive manufacturing, starting with today's infancy period, requires manufacturing firms to be flexible, ever-improving users of all available technologies to remain competitive. Advocates of additive manufacturing also predict that this arc of technological development will counter globalization, as end users will do much of their own manufacturing rather than engage in trade to buy products from other people and corporations. The real integration of the newer additive technologies into commercial production, however, is more a matter of complementing traditional subtractive methods rather than displacing them entirely.\nThe futurologist Jeremy Rifkin claimed that 3D printing signals the beginning of a third industrial revolution, succeeding the production line assembly that dominated manufacturing starting in the late 19th century.\nSocial change.\nSince the 1950s, a number of writers and social commentators have speculated in some depth about the social and cultural changes that might result from the advent of commercially affordable additive manufacturing technology. In recent years, 3D printing is creating significant impact in the humanitarian and development sector. Its potential to facilitate distributed manufacturing is resulting in supply chain and logistics benefits, by reducing the need for transportation, warehousing and wastage. Furthermore, social and economic development is being advanced through the creation of local production economies.\nOthers have suggested that as more and more 3D printers start to enter people's homes, the conventional relationship between the home and the workplace might get further eroded. Likewise, it has also been suggested that, as it becomes easier for businesses to transmit designs for new objects around the globe, so the need for high-speed freight services might also become less. Finally, given the ease with which certain objects can now be replicated, it remains to be seen whether changes will be made to current copyright legislation so as to protect intellectual property rights with the new technology widely available.\nAs 3D printers became more accessible to consumers, online social platforms have developed to support the community. This includes websites that allow users to access information such as how to build a 3D printer, as well as social forums that discuss how to improve 3D print quality and discuss 3D printing news, as well as social media websites that are dedicated to share 3D models. RepRap is a wiki based website that was created to hold all information on 3D printing, and has developed into a community that aims to bring 3D printing to everyone. Furthermore, there are other sites such as Pinshape, Thingiverse and MyMiniFactory, which were created initially to allow users to post 3D files for anyone to print, allowing for decreased transaction cost of sharing 3D files. These websites have allowed greater social interaction between users, creating communities dedicated to 3D printing.\nSome call attention to the conjunction of commons-based peer production with 3D printing and other low-cost manufacturing techniques. The self-reinforced fantasy of a system of eternal growth can be overcome with the development of economies of scope, and here, society can play an important role contributing to the raising of the whole productive structure to a higher plateau of more sustainable and customized productivity. Further, it is true that many issues, problems, and threats arise due to the democratization of the means of production, and especially regarding the physical ones. For instance, the recyclability of advanced nanomaterials is still questioned; weapons manufacturing could become easier; not to mention the implications for counterfeiting and on intellectual property. It might be maintained that in contrast to the industrial paradigm whose competitive dynamics were about economies of scale, commons-based peer production 3D printing could develop economies of scope. While the advantages of scale rest on cheap global transportation, the economies of scope share infrastructure costs (intangible and tangible productive resources), taking advantage of the capabilities of the fabrication tools. And following Neil Gershenfeld in that \"some of the least developed parts of the world need some of the most advanced technologies\", commons-based peer production and 3D printing may offer the necessary tools for thinking globally but acting locally in response to certain needs.\nLarry Summers wrote about the \"devastating consequences\" of 3D printing and other technologies (robots, artificial intelligence, etc.) for those who perform routine tasks. In his view, \"already there are more American men on disability insurance than doing production work in manufacturing. And the trends are all in the wrong direction, particularly for the less skilled, as the capacity of capital embodying artificial intelligence to replace white-collar as well as blue-collar work will increase rapidly in the years ahead.\" Summers recommends more vigorous cooperative efforts to address the \"myriad devices\" (e.g., tax havens, bank secrecy, money laundering, and regulatory arbitrage) enabling the holders of great wealth to \"a paying\" income and estate taxes, and to make it more difficult to accumulate great fortunes without requiring \"great social contributions\" in return, including: more vigorous enforcement of anti-monopoly laws, reductions in \"excessive\" protection for intellectual property, greater encouragement of profit-sharing schemes that may benefit workers and give them a stake in wealth accumulation, strengthening of collective bargaining arrangements, improvements in corporate governance, strengthening of financial regulation to eliminate subsidies to financial activity, easing of land-use restrictions that may cause the real estate of the rich to keep rising in value, better training for young people and retraining for displaced workers, and increased public and private investment in infrastructure development—e.g., in energy production and transportation.\nMichael Spence wrote that \"Now comes a ... powerful, wave of digital technology that is replacing labor in increasingly complex tasks. This process of labor substitution and disintermediation has been underway for some time in service sectors—think of ATMs, online banking, enterprise resource planning, customer relationship management, mobile payment systems, and much more. This revolution is spreading to the production of goods, where robots and 3D printing are displacing labor.\" In his view, the vast majority of the cost of digital technologies comes at the start, in the design of hardware (e.g. 3D printers) and, more important, in creating the software that enables machines to carry out various tasks. \"Once this is achieved, the marginal cost of the hardware is relatively low (and declines as scale rises), and the marginal cost of replicating the software is essentially zero. With a huge potential global market to amortize the upfront fixed costs of design and testing, the incentives to invest [in digital technologies] are compelling.\"\nSpence believes that, unlike prior digital technologies, which drove firms to deploy underutilized pools of valuable labor around the world, the motivating force in the current wave of digital technologies \"is cost reduction via the replacement of labor\". For example, as the cost of 3D printing technology declines, it is \"easy to imagine\" that production may become \"extremely\" local and customized. Moreover, production may occur in response to actual demand, not anticipated or forecast demand. Spence believes that labor, no matter how inexpensive, will become a less important asset for growth and employment expansion, with labor-intensive, process-oriented manufacturing becoming less effective, and that re-localization will appear in both developed and developing countries. In his view, production will not disappear, but it will be less labor-intensive, and all countries will eventually need to rebuild their growth models around digital technologies and the human capital supporting their deployment and expansion. Spence writes that \"the world we are entering is one in which the most powerful global flows will be ideas and digital capital, not goods, services, and traditional capital. Adapting to this will require shifts in mindsets, policies, investments (especially in human capital), and quite possibly models of employment and distribution.\"\nNaomi Wu regards the usage of 3D printing in the Chinese classroom (where rote memorization is standard) to teach design principles and creativity as the most exciting recent development of the technology, and more generally regards 3D printing as being the next desktop publishing revolution.\nEnvironmental change.\nThe growth of additive manufacturing could have a large impact on the environment. As opposed to traditional manufacturing, for instance, in which pieces are cut from larger blocks of material, additive manufacturing creates products layer-by-layer and prints only relevant parts, wasting much less material and thus wasting less energy in producing the raw materials needed. By making only the bare structural necessities of products, additive manufacturing also could make a profound contribution to lightweighting, reducing the energy consumption and greenhouse gas emissions of vehicles and other forms of transportation. A case study on an airplane component made using additive manufacturing, for example, found that the component's use saves 63% of relevant energy and carbon dioxide emissions over the course of the product's lifetime. In addition, previous life-cycle assessment of additive manufacturing has estimated that adopting the technology could further lower carbon dioxide emissions since 3D printing creates localized production, and products would not need to be transported long distances to reach their final destination.\nContinuing to adopt additive manufacturing does pose some environmental downsides, however. Despite additive manufacturing reducing waste from the subtractive manufacturing process by up to 90%, the additive manufacturing process creates other forms of waste such as non-recyclable material (metal) powders. Additive manufacturing has not yet reached its theoretical material efficiency potential of 97%, but it may get closer as the technology continues to increase productivity.\nSome large FDM printers which melt high-density polyethylene (HDPE) pellets may also accept sufficiently clean recycled material such as chipped milk bottles. In addition these printers can use shredded material coming from faulty builds or unsuccessful prototype versions thus reducing overall project wastage and materials handling and storage. The concept has been explored in the RecycleBot.", "Engineering,_Manufacturing": 0.9999687672, "qwen": "Yes"}
{"id": "1876560", "revid": "1307262", "url": "https://en.wikipedia.org/wiki?curid=1876560", "title": "Intermediate good", "text": "Intermediate goods, producer goods or semi-finished products are goods, such as partly finished goods, used as inputs in the production of other goods including final goods. A firm may make and then use intermediate goods, or make and then sell, or buy then use them. In the production process, intermediate goods either become part of the final product, or are changed beyond recognition in the process.\nThis means intermediate goods are resold among industries.\nIntermediate goods are not counted in a country's GDP, as that would mean double counting, as the final product only should be counted, and the value of the intermediate good is included in the value of the final good.\nThe value-added method can be used to calculate the amount of intermediate goods incorporated into GDP. This approach counts every phase of processing included in production of final goods.\nCharacterization of intermediate goods as physical goods can be misleading, since, in advanced economies, about half of the value of intermediate inputs consist of services.\nIntermediate goods generally can be made and used in three different ways. First, a company can make and use its own intermediate goods. Second, a company can manufacture intermediate goods and sell them to others. Third, a company can buy intermediate goods to produce either secondary intermediate goods or final goods.", "Engineering,_Manufacturing": 0.9999455214, "qwen": "Yes"}
{"id": "49937269", "revid": "15996738", "url": "https://en.wikipedia.org/wiki?curid=49937269", "title": "Operations engineering", "text": "Operations engineering is a branch of engineering that is mainly concerned with the analysis and optimization of operational problems using scientific and mathematical methods. More frequently it has applications in the areas of Broadcasting/Industrial Engineering and also in the Creative and Technology Industries.\nOperations engineering is considered to be a subdiscipline of Operations Research and Operations Management.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "26106381", "revid": "1053079989", "url": "https://en.wikipedia.org/wiki?curid=26106381", "title": "Quadrac", "text": "A QUADRAC is a special type of \"thyristor\" which combines a DIAC and a TRIAC in a single package. The DIAC is the triggering device for the TRIAC. Thyristors are four-layer (PNPN) semiconductor devices that act as switches, rectifiers or voltage regulators in a variety of applications. When triggered, thyristors turn on and become low-resistance current paths. They remain so even after the trigger is removed, and until the current is reduced to a certain level (or until they are triggered off). Diacs are bi-directional diodes that switch AC voltages and trigger triacs or silicon-controlled rectifiers (SCRs). Except for a small leakage current, diacs do not conduct until the breakover voltage is reached. Triacs are three-terminal, silicon devices that function as two SCRs configured in an inverse, parallel arrangement. They provide load current during both halves of the AC supply voltage. By combining the functions of diacs and triacs, QUADRACs eliminate the need to buy and assemble discrete parts.\nQUADRACs are used in lighting control, speed control, and temperature modulation control applications. They carry performance specifications such as peak repetitive off voltage, peak repetitive reverse voltage, root mean square (RMS) on-state current, and temperature junction. Peak repetitive off voltage is the maximum, instantaneous value of the off-state voltage that occurs across a thyristor, including all repetitive transient voltages and excluding all non-transient voltages. Peak repetitive reverse voltage is the maximum peak reverse voltage that may be applied continuously to the main terminals (anode and cathode) of QUADRACs. RMS on-state current is the maximum RMS current allowed for the specified use-case temperature. Temperature junction for QUADRACs is expressed as a full-required range.\nPackages.\nQUADRACs are available in a variety of integrated circuit (IC) package types with different numbers of pins. Basic IC packages types for QUADRACs include discrete packaging (DPAK), power packaging (PPAK), and in-line packaging (IPAK). Other IC package types include diode outline (DO), transistor outline (TO), and small outline transistor (SOT). QUADRACs that use metal electrode leadless face (MELF) packaging have metallized terminals at each end of a cylindrical body. Other available package types for QUADRACs include thin small outline package (TSOP), thin shrink small outline L-leaded package (TSSOP), and thin small outline J-lead (TSOJ) package.", "Engineering,_Manufacturing": 0.9990847111, "qwen": "Yes"}
{"id": "26109619", "revid": "432843", "url": "https://en.wikipedia.org/wiki?curid=26109619", "title": "Thermosonic bonding", "text": "Thermosonic bonding is widely used to wire bond silicon integrated circuits into computers. Alexander Coucoulas was named \"Father of Thermosonic Bonding\" by George Harman, the world's foremost authority on wire bonding, where he referenced Coucoulas's leading edge publications in his book, \"Wire Bonding In Microelectronics\". Owing to the well proven reliability of thermosonic bonds, it is extensively used to connect the central processing units (CPUs), which are encapsulated silicon integrated circuits that serve as the \"brains\" of today's computers.\nDescription.\nA thermosonic bond is formed using a set of parameters which include ultrasonic, thermal and mechanical (force) energies. A thermosonic bonding machine includes a magnetostrictive or piezoelectric-type transducer which is used to convert electrical energy into vibratory motion which is known as piezoelectricity. The vibratory motion travels along the coupler system, a portion which is tapered to serve as the velocity transformer. The velocity transformer amplifies the oscillatory motion and delivers it to a heated bonding tip. It is akin to a friction bond, since the introduction of ultrasonic energy (via a bonding tool vertically attached to an ultrasonic transformer or horn) simultaneously delivers a force and vibratory or scrubbing motion to the interfacial contact points between a pre-heated deforming lead-wire and the metallized pads of a silicon integrated circuit. In addition to the delivery of thermal energy, the transmission of ultrasonic vibratory energy creates an ultrasonic softening effect by interacting at the atomic lattice level of the preheated lead wire. These two softening effects dramatically facilitates the lead wire deformation by forming the desirable contact area using relatively low temperatures and forces. As a result of the frictional action and ultrasonic softening induced in the preheated lead wire during the bonding cycle, thermosonic bonding can be used to reliably bond high melting point lead wires (such as gold and lower cost aluminum and copper) using relatively low bonding parameters. This ensures that the fragile and costly silicon integrated circuit chip is not exposed to potentially damaging conditions by having to use higher bonding parameters (ultrasonic energy, temperatures or mechanical forces) to deform the lead wire in forming the required contact area during the bonding process.\nBackground.\nA thermosonic bond falls in the category of a solid state metallic bond which is formed by mating two metal surfaces well below their respective melting points. Coucoulas introduced Thermosonic bonding which significantly improved upon the bond-reliability produced by available commercial solid-state bonding machines where he pre-heated the lead wire (and/or metallized silicon chip) prior to introducing an ultrasonic energy cycle. In addition to thermal softening the lead wire, the subsequent delivery of ultrasonic energy produced further softening by interacting at the atomic lattice level of the heated wire (known as ultrasonic softening). These two independent softening mechanisms (pre-heating lead wire and delivering the ultrasonic energy at the atomic lattice level) eliminated the incidences of cracking the fragile and costly silicon chip which were observed by Coucoulas when using earlier commercially available solid-state bonding machines. The improvement occurs because pre-heating and ultrasonic softening the lead-wire dramatically facilitated its deformation in forming the required contact area while using a relatively low set of bonding parameters. Depending on the temperature level and material properties of the lead wire, the onset of recrystallization (metallurgy) or hot working of the deforming wire can occur while it is forming the required contact area. Recrystallization takes place in the strain hardening region of the lead wire where it aids in the softening effect. If the wire was ultrasonically deformed at room temperature, it would tend to extensively strain hardened (cold working) and therefore tend to transmit damaging mechanical stresses to the silicon chip. Thermosonic bonding, initially referred to as Hot Work Ultrasonic Bonding by Alexander Coucoulas, was found to bond a wide range of conductive metals such as aluminum and copper wires to tantalum and palladium thin films deposited on aluminum oxide and glass substrates all of which simulated the metallized silicon chip.\nApplications.\nAt present, the majority of connections to the silicon integrated circuit chip are made using thermosonic bonding because it employs lower bonding temperatures, forces and dwell times than thermocompression bonding, as well as lower vibratory energy levels and forces than ultrasonic bonding to form the required bond area. Therefore the use of thermosonic bonding eliminates damaging the relatively fragile silicon integrated circuit chip during the bonding cycle. The proven reliability of thermosonic bonding has made it the process of choice, since such potential failure modes could be costly whether they occur during the manufacturing stage or detected later, during an operational field-failure of a chip which had been connected inside a computer or a myriad of other microelectronic devices.\nThermosonic bonding is also used in the flip chip process which is an alternate method of electrically connecting silicon integrated circuits.\nJosephson effect and superconducting interference (DC SQUID) devices use the thermosonic bonding process as well. In this case, other bonding methods would degrade or even destroy YBaCuO7 microstructures, such as microbridges, Josephson junctions and superconducting interference devices (DC SQUID).\nWhen electrically connecting light-emitting diodes with thermosonic bonding techniques, an improved performance of the device has been shown.", "Engineering,_Manufacturing": 1.0000064373, "qwen": "Yes"}
{"id": "4159592", "revid": "486612", "url": "https://en.wikipedia.org/wiki?curid=4159592", "title": "Demand-chain management", "text": "Demand-chain management (DCM) is the management of relationships between suppliers and customers to deliver the best value to the customer at the least cost to the demand chain as a whole. Demand-chain management is similar to supply-chain management but with special regard to the customers.\nDemand-chain-management software tools bridge the gap between the customer-relationship management and the supply-chain management. The organization's supply chain processes are managed to deliver best value according to the demand of the customers. DCM creates strategic assets for the firm in terms of the overall value creation as it enables the firm to implement and integrate marketing and supply chain management (SCM) strategies that improve its overall performance. A study of the university in Wageningen (the Netherlands) sees DCM as an extension of supply chain management, due to its incorporation of the market-orientation perspective on its concept.\nDemand-driven supply network.\nA \"Demand-driven supply network (DDSN)\" is one method of supply-chain management which involves building supply chains in response to demand signals. The main force of DDSN is that it is driven by customers demand. In comparison with the traditional supply chain, DDSN uses the pull technique. It gives DDSN market opportunities to share more information and to collaborate with others in the supply chain.\nDDSN uses a capability model that consist of four levels. The first level is \"Reacting\", the second level is \"Anticipating\", the third level is \"Collaborating\" and the last level is \"Orchestrating\". The first two levels focus on the internal supply chain while the last two levels concentrate on external relations throughout the Extended Enterprise.\nIn a demand-driven chain, a customer activates the flow by ordering from the retailer, who reorders from the wholesaler, who reorders from the manufacturer, who reorders raw materials from suppliers. Orders flow backward, up the chain, in this structure.\nMany companies are trying to shift from a build-to-forecast to a build-to-order discipline. The property of being demand-driven is one of degree: Being \"0 percent\" demand-driven means all production/inventory decisions are based on forecasts, and so, all products available for sale to the end user is there by virtue of a forecast. This could be the case of fashion goods, where the designer may not know how buyers will react to a new design, or the beverage industry, where products are produced based on a given forecast. A \"100 percent\" demand-driven is one in which the order is received before production begins. The commercial aircraft industry match to this description. In most cases, no production occurs until the order is received.\nCompetitive advantages.\nTo create sustainable competitive advantages with DDSN, companies have to do deal with three conditions: \"Alignment\" (create shared incentives), \"Agility\" (respond quickly to short-term change) and \"Adaptability\" (adjust design of the supply chain).\nMisconceptions.\nThere are five commonly-made misconceptions of demand driven (DDSN):\nAn important component of DDSN is DDM (\"real-time\" demand driven manufacturing). DDM gives customers the opportunity to say what they want, where and when.\nDemand-driven execution.\nDemand-chain management is the same as supply chain management, but with emphasis on consumer pull vs. supplier push. The demand chain begins with customers, then funnels through any resellers, distributors, and other business partners who help sell the company's products and services. The demand chain includes both direct and indirect sales forces. Customers demand is hard to detect because out of stock situations (OOS) falsify data collected from POS-Terminals. According to studies of Corsten/Gruen (2002, 2008) the OOS-rate is about 8%. For products under sales promotion OOS rates up to 30% exist. Reliable information about demand is necessary for DCM therefore lowering OOS is a main factor for successful DCM.\nCorsten and Gruen describe key factors for lowering OOS-rates:\nImplementation of system supported processes leads to the new technology Extreme Transaction Processing described by Gartner Research. This technology allows to process the huge amount of data (POS, RFID) in real time providing information for store managers, shelve managers and the supply chain.\nAccording to studies of Ayers, in order to find appropriate methods which fitting different kinds of companies, the first thing companies should do is to assess their progress toward achieving world-class levels of supply chain management. In order to raise demand-driven levels, companies need to undertake a systematic effort that has three elements:\nDemand-driven supply-chain assessment.\nCompanies must have an appropriate performance-measurement system to be applied on a regular basis to identify areas to be improved in order to establish a sustainable continuous improvement process. According to Dale and Ritchie, to use self-assessment process is very important. The self-assessment will allow organizations to discern its strengths and gaps, and define improvement actions linked to the business planning process. There are some necessary criteria for a successful self-assessment process:\nThe importance of supply chain and operations audit process which represents a fundamental step to support improvement projects. According to study of Salama, the core element of audits is the diagnostic stage and that no audit can be considered successful unless it really provides a thorough understanding of how the constituent elements of an organization interact with one another (e.g., people, processes and technologies), that is the interactions which constrain the system, and how these interactions are reflected on the market-driven performance. The provided a set of features and requirements for an audit methodology that can be considered when developing a DDSC assessment:", "Engineering,_Manufacturing": 0.9999519587, "qwen": "Yes"}
{"id": "36787181", "revid": "41840956", "url": "https://en.wikipedia.org/wiki?curid=36787181", "title": "Showa Aircraft Industry", "text": " is a Japanese company. Its headquarters are at Akishima-shi, Tokyo Prefecture, a region of Tokyo Metropolis. It was established in 1937 as a manufacturer of military aircraft in Akishima-shi. In World War II it was one of two companies manufacturing the Showa/Nakajima L2D, a license-built Douglas DC-3 variant. It also manufactured other military aircraft.", "Engineering,_Manufacturing": 1.0000070333, "qwen": "Yes"}
{"id": "36808856", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=36808856", "title": "Costimator", "text": "Costimator is an American series of cost estimating software developed by Thomas Charkiewicz in 1982 and is designed to model manufacturing costs. The software is designed, developed and marketed by MTI of West Springfield, MA.\nHistory.\nCostimator was designed by Thomas Charkiewicz, a former machinist and manufacturing manager who studied computer-aided manufacturing at the University of Massachusetts. Costimator was released in late 1982, designed to model manufacturing costs.\nIn 2002, IBM bought Costimator OEM from MTI Systems, Inc. Many of the products on the market focused on machine shop operations. Costimator had its roots in the machining industry, but later branched out to include several other manufacturing processes.\nJohn Kagan, the former manager of PC Cost Management at IBM and Lenovo estimated that between 2003 and 2004, IBM saved more than $10 million using Costimator.\nCostimator also includes a function known as IQ builder which customers can use to model their own manufacturing process based on historical data. The data was derived from the company’s customers in addition to various independent industry sources. Labor costs come from the U.S. Bureau of Labor Statistics.\nIn 2009, MTI Systems, Inc. reached an agreement with European distributor Premier Manufacturing Solutions, LTD (Stockport, UK) to market its flagship products Costimator OEM and Costimator JS to companies throughout Europe. In February 2011, Cimtronics and MTI Systems, Inc. also agreed to terms on a distribution partnership.", "Engineering,_Manufacturing": 0.9954832196, "qwen": "Yes"}
{"id": "27208690", "revid": "12097632", "url": "https://en.wikipedia.org/wiki?curid=27208690", "title": "Hydrogen gas porosity", "text": "Hydrogen gas porosity is an aluminium casting defect in the form of a porosity or void in an aluminium casting caused by a high level of hydrogen gas (H2) dissolved in the aluminium at liquid phase. The solubility of hydrogen in solid aluminium is much smaller than in liquid aluminium. As the aluminium freezes, some of the hydrogen comes out of solution and forms bubbles, creating porosity in the solid aluminium.\nAluminium foundries want to produce high-quality aluminum castings with minimum porosity. Hydrogen porosity can be reduced by reducing the amount of hydrogen in the liquid aluminium alloy, by degassing or sparging. (Sometimes a small hydrogen concentration is intentionally maintained; some very fine hydrogen porosity can be preferable to internal voids caused by shrinkage.) Directional solidification can drive impurities to one end of the casting.\nThe hydrogen problem.\nHydrogen forms whenever molten aluminium comes into contact with water vapor, and easily dissolves into the melt. The gas tends to come out of the solution and forms bubbles when the melt solidifies.\nThe detrimental effects arising from the presence of an excess of dissolved hydrogen in aluminium are numerous. Hydrogen causes porosity in aluminum products leading to many casting defects, reduced mechanical properties like fatigue and lower corrosion resistance. Several methods are used to reduce the amount of dissolved hydrogen from the melt, such as furnace fluxing prior to the casting process or using in-line degassing equipment during the casting process.\nDirect hydrogen measurement.\nAn on-line method of measuring hydrogen in aluminum is then required to characterize and optimize the process, which helps ensure the quality of outgoing products and monitors the performance of these degassing processes. Traditional laboratory methods, such as hot extraction, are too expensive for routine quality assurance, and too slow for effective process control. The Reduced Pressure Test (RPT) is often used on the foundry floor. The RPT is a semi-quantitative method with limited accuracy that provides an indication of the hydrogen level.\nHydrogen analyzer.\nA hydrogen analyzer can be used for direct measurement of hydrogen in liquid aluminium. Direct monitoring of hydrogen is possible using an on-line quantitative measurement technology based on a closed-loop gas recirculation method though a porous ceramic probe.\nSince its introduction in 1989, this gas recirculation method has been increasingly used by major aluminum producers.\nAn example of analyzer for direct hydrogen measurement in liquid aluminium is the Accurity. It works with a probe immersed in liquid aluminium and it uses the closed-loop recirculation method.\nOperation principle.\nThe closed loop recirculation is a proven method of directly monitoring hydrogen in molten aluminium. A small volume of carrier gas, usually nitrogen, is brought in contact with the melt by means of an immersed probe, and is continuously recirculated in the closed loop until its hydrogen content reaches equilibrium with the vapor pressure of H2 in the melt. The H2 concentration in the gas is measured and converted into a reading of the gas concentration in the metal. This method is fast, reproducible, and accurate, and can be used online on the factory floor.\nThe amount of H2 in the gas loop of the instrument is determined by a thermal conductivity sensor, which provides high reproducibility and a broad measurement range.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "39139120", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=39139120", "title": "Fillet weld", "text": "Fillet welding refers to the process of joining two pieces of metal together when they are perpendicular or at an angle. These welds are commonly referred to as tee joints, which are two pieces of metal perpendicular to each other, or lap joints, which are two pieces of metal that overlap and are welded at the edges. The weld is triangular in shape and may have a concave, flat or convex surface depending on the welder's technique. Welders use fillet welds when connecting flanges to pipes and welding cross sections of infrastructure, and when bolts are not strong enough and will wear off easily.\nThere are two main types of fillet weld: transverse fillet weld and parallel fillet weld.\nAspects.\nThere are 5 pieces to each fillet weld known as the root, toe, face, leg and throat. The root of the weld is the part of deepest penetration which is the opposite angle of the hypotenuse. The toes of the weld are essentially the edges or the points of the hypotenuse. The face of the weld is the outer visual or hypotenuse that you see when looking at a fillet weld. The legs are the other two sides of the triangular fillet weld. The leg length is usually designated as the size of the weld. The throat of the weld is the distance from the center of the face to the root of the weld. Typically the depth of the throat should be at least as thick as the thickness of metal you are welding.\nNotation.\nFillet welding notation is important to recognize when reading technical drawings. The use of this notation tells the welder exactly what is expected by the fabricator. The symbol for a fillet weld is in the shape of a triangle. This triangle will lie either below a flat line or above it with an arrow coming off of the flat line pointing to a joint. The flat line is called \"reference line\". The side on which the triangle symbol is placed is important because it gives an indication which side of the joint is to be intersected by the weld. It is recognized that there are two different approaches in the global market to designate the arrow side and other side on drawings; a description of the two approaches is contained in International Standard ISO 2553, they are called \"A-System\" (which is more commonly used in Europe) and \"B-System\" (which is basically the ANSI/AWS system used in the US). In \"A-System\" two parallel lines are used as reference line: one is a continuous line, the other is a dashed line. In the \"B-System\", there is only one reference line, which is a continuous line. If there is a single reference line (B-System) and the triangle is positioned below the line, then the weld is going to be on the arrow side. If there is a single reference line (\"B-System\") and the triangle is positioned above the line, then the weld is going to be on the opposite side of the arrow. When you find an arrow pointing to a joint with two triangles, one sitting below and one sitting above the line even with each other, then there is intended to be a fillet weld on the arrow side of the joint as well as the opposite side of the joint. If the weld is to be continuous around a piece of metal such as a pipe or square, then a small circle will be around the point where the flat line and arrow pointing to the joint are connected. Manufacturers also include the strength that the weld must be. This is indicated by a letter and number combination just before the flat line. Examples of this are \"E70\" meaning the arc electrode must have a tensile strength of . There are also symbols that describe the aesthetics of the weld. A gentle curve pointing away from the hypotenuse means a concave weld is required, a straight line parallel with the hypotenuse calls for a flat faced weld, and a gentle curve towards the hypotenuse calls for a convex weld. The surface of the weld can be manipulated either by welding technique or by use of machining or grinding tools after the weld is completed. When reading a manufacturers technical drawings, you might also come across weld dimensions. The weld can be sized in many different ways such as the length of the weld, the measurements of the legs of the weld, and the spaces between welds. Along with a triangle, there will usually be a size for the weld for example (”x”) to the left of the triangle. This means that the vertical leg of the weld is to be ” whereas the horizontal leg is to ”. To the right of the triangle, there will be a measurement of exactly how long the weld is supposed to be.\nIf the measurements of the drawing are in mm the welds are likewise measured in mm. For example, the weld would be 3 x 10, the mm being understood automatically.\nIntermittent fillet welds.\nAn intermittent fillet weld is one that is not continuous across a joint. These welds are portrayed as a set of two numbers to the right of the triangle instead of just one. The first number as mentioned earlier refers to the length of the weld. The second number, separated from the first by a “-”, refers to the pitch. The pitch is a measurement from midpoint to midpoint of the intermittent welds. Intermittent welding is used when either a continuous weld is not necessary, or when a continuous weld threatens the joint by warping. In some cases intermittent welds are staggered on both sides of the joint. In this case, the notation of the two triangles are not directly on top of each other. Instead, the side of the joint to receive the first weld will have a triangle further to the left than the following side’s triangle notation. As an end result of alternating intermittent fillet welds at each side, the space between welds on one side of the joint will be the midpoint of the opposite side’s weld.", "Engineering,_Manufacturing": 0.9996740818, "qwen": "Yes"}
{"id": "39174308", "revid": "575347", "url": "https://en.wikipedia.org/wiki?curid=39174308", "title": "Solid ground curing", "text": "Solid ground curing (SGC) is a photo-polymer-based additive manufacturing (or 3D printing) technology used for producing models, prototypes, patterns, and production parts, in which the production of the layer geometry is carried out by means of a high-powered UV lamp through a mask. As the basis of solid ground curing is the exposure of each layer of the model by means of a lamp through a mask, the processing time for the generation of a layer is independent of the complexity of the layer. SGC was developed and commercialized by Cubital Ltd. of Israel in 1986 in the alternative name of Soldier System. While the method offered good accuracy and a very high fabrication rate, it suffered from high acquisition and operating costs due to system complexity. This led to poor market\nacceptance. While the company still exists, systems are no longer being sold. Nevertheless, it's still an interesting example of the many technologies other than stereolithography, its predeceasing rapid prototyping process that also utilizes photo-polymer materials. Though Objet Geometries Ltd. of Israel retains intellectual property of the process after the closure of Cubital Ltd. in 2002, the technology is no longer being produced.\nTechnology.\nSolid ground curing utilizes the general process of hardening of photopolymers by a complete lighting and hardening of the entire surface, using specially prepared masks. In SGC process, each layer of the prototype is cured by exposing to an ultra violet (UV) lamp instead of by laser scanning. So that, every portion in a layer are simultaneously cured and do not require any post-curing processes. The process contains the following steps.\nAdvantages and disadvantages.\nThe primary advantage of the solid ground curing system is that it does not require a support structure since wax is used to fill the voids, highly accurate products can be obtained. The model produced by SGC process is comparatively accurate in the Z-direction because the layer is milled after each light-exposure process. Although it offers good accuracy coupled with high throughput, it produces too much waste and its operating costs are comparatively high due to system complexity.", "Engineering,_Manufacturing": 1.0000064373, "qwen": "Yes"}
{"id": "56266877", "revid": "525927", "url": "https://en.wikipedia.org/wiki?curid=56266877", "title": "Localized pulsed electrodeposition", "text": "Localized pulsed electrodeposition (L-PED) is a technique for direct 3D printing of free-standing and layer-by-layer micro/nano-scale metallic structures at the tip of an electrolyte containing nozzle. The method follows the same principle for metal deposition as the traditional electrodeposition (electroplating), however the area of deposition is limited by the size of a liquid bridge (meniscus) formed between the nozzle tip and the substrate. The unique advantage of the L-PED process is the possibility of the control over the spatial microstructure of the printed metal in 3D geometries by adjusting deposition parameters (peak current density, on time, off time, etc.). This method can be used in various applications in nanotechnology, in particular for 3-dimensional electronics and sensors.\n3D Printing Process.\nA nozzle with a few microns to sub-micron tip, containing the electrolyte of the metal of interest, works as the printing tool bit. When the nozzle approaches the substrate, the meniscus is formed at the nozzle tip, and functions as a confined electrodeposition bath. A two-electrode configuration was employed for the L-PED process, consists of a working electrode (the substrate) and a counter electrode (a metal wire which is inserted within the micropipette). The metal ions are reduced at the growth front within the meniscus area and deposited at the substrate by application of an appropriate pulsed electric potential between the electrodes. The precise and controlled motion of the relative position of the nozzle and the substrate results in printing of desired 3D pure metallic objects.\nInvolved Mechanisms.\nThe L-PED involves several ionic transport mechanisms including convection (driven by evaporation), diffusion and migration. These transport mechanisms are affected by short duration ON-pulses, and longer duration OFF-pulses. Subsequently, the ion concentration and the current density constantly change in each pulse cycle. These parameters eventually regulate the printing rate and the microstructure of the printed metal in L-PED. \nHistorical background.\nThe localized electrodeposition was first reported by a group at University of Illinois at Urbana-Champaign in 2006, and was used to fabricate high-density and high quality interconnects and wire bonds. A research group at University of Texas at Dallas studied the process further and determined that through the application of a pulsed voltage, nanotwinned metals can be 3D-printed. They demonstrated the ambient environment L-PED process for direct printing of 3D free-standing nanotwinned Cu nanostructures for the first time.", "Engineering,_Manufacturing": 0.9999965429, "qwen": "Yes"}
{"id": "56278630", "revid": "4773966", "url": "https://en.wikipedia.org/wiki?curid=56278630", "title": "Electrofusion welding", "text": "Electrofusion welding is a form of resistive implant welding used to join pipes. A fitting with implanted metal coils is placed around two ends of pipes to be joined, and current is passed through the coils. Resistive heating of the coils melts small amounts of the pipe and fitting, and upon solidification, a joint is formed. It is most commonly used to join polyethylene (PE) and polypropylene (PP) pipes. Electrofusion welding is the most common welding technique for joining PE pipes. Because of the consistency of the electrofusion welding process in creating strong joints, it is commonly employed for the construction and repair of gas-carrying pipelines. The development of the joint strength is affected by several process parameters, and a consistent joining procedure is necessary for the creation of strong joints. \nAdvantages and disadvantages.\nAdvantages of electrofusion welding:\nDisadvantages of electrofusion welding:\nEquipment.\nElectrofusion welds are performed by attaching a controlled power supply to the electrofusion fitting. There are typically two modes of operation.\nConstant voltage is typically used for high pressure pipelines such as mains gas and water. Fittings are fitted with a barcode specified to an ISO standard.\nTypically fittings will be welded at 39.5v, but manufacturers can choose voltages in whole numbers from 8 to 48v. The welding time is specified on the label in seconds or minutes\nAccessories.\nElectrofusion welding employs fittings that are placed around the joint to be welded. Metal coils are implanted into the fittings, and electric current is run through the coils to generate heat and melt part of the pipes, forming a joint upon solidification. There are two possible fittings used in electrofusion welding: couplers and tapping tees (saddles). Coupler fittings contain two separate regions of coils, creating two distinct fusion zones during welding. The inner diameter of the coupler is typically slightly larger than the outer diameter of the pipes. This is to increase the ease of assembly in the field and allows for minor inconsistencies in pipe diameter. Proper insertion of the pipes in the coupler is critical for the creation of a strong joint. Incorrect placement of the coupler can cause the coils to move and lead to the extrusion of molten polymer material from the joint, reducing the joint's strength. Tapping tees, or saddles, are less common but operate under the same principles as a coupler. They require clamping to ensure a proper fit up with the pipes.\nFitting installation.\nInstallation of couplers and tapping tee fittings require slightly different procedures. Common installation steps for each are given below.\nPower requirements.\nElectrofusion welding requires electrical current to be passed through the coils implanted in the fittings. Since the electrical energy input is an excellent indicator of the joint strength that develops during fusion, it is necessary to have consistent electrical power input. Energy input during the joining process is typically measured by controlling the time it takes for the current to pass through the fitting. However, energy input can also be monitored by controlling overall temperature, molten polymer temperature, or molten polymer pressure. \nA control box takes electrical power from a generator and converts it into an appropriate voltage and current for electrofusion joining. This provides consistent energy input for each application. The most common input voltage for electrofusion welding fittings is 39.5V, as it provides the best results without risking operator safety. The current is input as an alternating current (AC) waveform.\nWelding process.\nStages during welding.\nElectrofusion welding is characterized by 4 distinct stages that occur during the welding process: \nDuring the incubation period, heat is introduced into the joint as current is passed through the coil. Although there is no joint strength at this point, the polymer expands and the joint gap is filled. During joint formation and consolidation, melting begins. Melt pressure has begun to build, and the majority of the joint's strength is developed during this stage. The strength increase is due primarily to the constraint of the increasing molten material by the cold zones in the surrounding fitting. The plateau region signals the stabilization of the joint strength. Despite this, the heat of the joint is still increasing with time during this stage. The cooling period occurs after current is no longer applied to the coils. The molten polymer material solidifies and forms the joint.\nCurrent during welding.\nMost electrofusion welding power supplies are constant voltage machines. Constant current machines would provide more consistent energy input due to the smaller fluctuations in current applied to the coils during welding. However, this additional consistency is generally not worth the higher cost of these machines. When a constant voltage machine is used, the value of the applied current slowly decreases throughout the welding process. This effect is due to the increasing resistance of the coils as energy is applied. As heat is generated in the coils, their temperature increases, leading to a higher electrical resistance in the coils. This increased electrical resistance causes a smaller current to be generated from the same voltage level as the process progresses. The extent of the current decrease is determined by the material used for the coil. The energy input per unit area can be calculated and used to monitor the process. Typical values for this range from 2-13 J/mm2, with a value of 3.9 J/mm2 having been found to produce the strongest joints. \nTemperature during welding.\nLarge temperature gradients exist in the electrofusion joint during the fusion cycle. The low thermal conductivity of polymers is the main cause of these large gradients. Recent efforts to model the thermal history at various locations using finite element modeling have been successful. \nPressure during welding.\nAs the temperature in the joint increases, polymer begins to melt and a fusion zone is formed. The molten polymer in the fusion zone exerts an outward force on the surrounding solid polymer material, referred to as \"cold zones\". These cold zones cause a pressure to develop in the molten fusion zone. The pressure in the fusion zone takes some time to reach its maximum value, usually not reaching the peak until about a quarter of the way into the joining process. After the current is shut off and cooling begins, the pressure slowly decreases until the joint is uniform temperature.\nProperties of joints.\nThe strength of an electrofusion joint is measured using tensile and peel tests on coupons taken from the fusion zone of the joint. Two methods have been developed to assess the effect of fusion time on joint strength: \nThe strength of the joint develops throughout the welding process, and this development is affected by the fusion time, joint gap, and pipe material. These are detailed below.\nEffect of fusion time on joint strength.\nAs fusion time begins, there is an incubation period where no strength develops. Once enough time has passed for the molten material to begin solidifying, the joint strength begins to develop before plateauing at the maximum strength. If power is applied after full joint strength is achieved, the strength will start to decline slowly. \nEffect of joint gap on joint strength.\nThe joint gap is the distance between the electrofusion fitting and the pipe material. When no joint gap is present, the resulting joint strength is high but not maximum. As joint gap increases, the joint strength increases to a point, then begins to decline fairly sharply. At larger gaps sufficient pressure cannot build during the fusion time, and the joint strength is low. The effect of joint gap on strength is why the scraping of the pipes before welding is a critical step. Uneven or inconsistent scraping can result in areas where the joint gap is large, leading to low joint strength. \nEffect of pipe material on joint strength.\nPipe materials with higher molecular weights (MW), or densities, will have slower material flow rates when in the molten state during fusion. Despite the differences in flow rates, the final joint strength is generally consistent over a fairly wide range of pipe molecular weights. ", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "56288481", "revid": "14813571", "url": "https://en.wikipedia.org/wiki?curid=56288481", "title": "FAA Order 8100.8", "text": "FAA Order 8100.8, Designee Management Handbook, establishes \"policy and procedures for the selection, appointment, orientation, training, oversight, renewal tracking, and termination of certain representatives of the Administrator\" of the Federal Aviation Administration. In particular, it is a resource for individuals interested in becoming a Designated Engineering Representative (DER).\nDERs are not employees of the FAA. FAA employees must resign from the FAA before obtaining DER certification.\nSubject to FAA Notice 8000.372 \"Manufacturing Designee Management System Implementation\" (2014), all Designated Airworthiness Representatives for Manufacturing (DAR-Fs) and Designated Manufacturing Inspection Representatives (DMIRs) are subject to the policy in FAA Order 8000.95, \"Designee Management Policy\". Order 8100.8 is no longer applicable to these two designations.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "5339220", "revid": "17218984", "url": "https://en.wikipedia.org/wiki?curid=5339220", "title": "Automobile repair shop", "text": "An automobile repair shop (also known regionally as a garage or a workshop) is an establishment where automobiles are repaired by auto mechanics and technicians. The customer interface is typically a service advisor, traditionally called a service writer.\nTypes.\nAutomotive garages and repair shops can be divided into following categories:\nService station.\nFirst appearing in the early 1900s, many filling stations offered vehicle repair services as part of their full service operation. This once popular trend has declined significantly over the years as many locations found it more profitable to exchange vehicle service bays for grocery isles, which ultimately lead to the emergence of the quick oil change industry.\nLubrication/safety shop.\nCommonly referred to as a quick lube or express service shop, this type of facility specializes in preventive maintenance and safety inspections rather than repairs. Product sales are typically limited to automotive fluids, belts and hoses. With a focus on basic procedures, labor is often performed by entry-level technicians which simplifies the business overhead resulting in a less expensive service as compared to a traditional automotive workshop. \nNew car dealership.\nIn the United States, new car dealerships have service departments that are certified by their respective OEM (Original Equipment Manufacturer) to perform warranty and recall repairs. Customer-pay repairs can also be completed, however most service departments tend to only work on the vehicle brand of which they are a dealer. Dealership technicians must complete additional training provided by the OEM, and in doing so become specialized and certified for that particular vehicle make.\nIndependent auto repair shop.\nIndependent auto repair shops are businesses that are independently owned and operated. In states regulating a smog or emission test, often, independent auto repair shops offer these tests as well. These may also include regional or national chains and franchises. It is rather common for a dealership technician to start this type of competing business after leaving the employment of a new car dealership. Independent automobile repair shops in the US may also achieve OEM certification through manufacturer sponsored programs. European Union law (The EC Block Exemption Regulation 1400/2002 (October 2003)) permits motorists more flexibility in selecting where their car is serviced. Maintenance and service work does not have to be done by the dealership providing that the independent garage uses Original Equipment 'Matching Quality' parts and follows the manufacturer's service schedules. The Block Exemption Regulation (BER) covers service and maintenance during the warranty period and prohibits vehicle manufacturers' warranties from including restrictive conditions.\nFleet shop.\nA shop that is dedicated to repairing and maintaining a particular group of vehicles is called a fleet shop. Common examples of a fleet include taxi cabs, police cars, mail trucks and rental vehicles. Similar to a lubrication/safety shop, a fleet shop focuses primarily on preventative maintenance and safety inspections, and will often outsource larger or more complex repairs to another repair facility.\nEngine machine shop.\nShops that specialize in cylinder head and cylinder block machining are called engine machine shops. These facilities utilize large electromechanical machines that are not found in the average automotive repair shop. Engine machining is typically performed by an ASE certified machinist in order to correct worn or damaged engine components as an alternative to component replacement. Performance engine building is another popular service frequently offered by this type of workshop.\nTire and wheel shop.\nSome repair shops specialize in tires and wheels. These businesses usually have a large inventory of tires and aftermarket wheels, some of which may be on display while others require special ordering. In addition to parts, common labor services include tire rotation, balancing and repair as well as wheel alignment which can prevent premature tire wear.\nIn the Philippines, roadside tire repair shops are called vulcanizing shops in Philippine English. They specialize in quickly and cheaply repairing flat tires by patching punctures with a rubber compound patch.\nMuffler shop.\nA muffler shop, also called an exhaust shop, is a business model that concentrates solely on the engine exhaust system. These facilities utilize large tubing benders which allow a technician to fabricate a new exhaust system out of otherwise straight lengths of pipe. Welding is often necessary in this line of work.\nAuto body.\nAutomotive repair shops that specialize in bodywork repair are known as body shops. Auto body technicians can perform paintwork repairs to scratches, scuffs and dents, as well as repairs to the bodies of vehicles damaged by collisions. Many body shops now offer paintless dent repair and auto glass replacement. Automotive repair shops that specialize in auto glass repair are known as auto glass repair shops. They offer auto glass repairs to chips, cracks and shattered glass. The types of glass they repair include windshields, car windows, quarter glass and rear windows. This type of damage is often caused by hail, stones, wild animals, fallen trees, automobile theft and vandalism.\nMobile mechanics.\nMobile mechanics provide doorstep repair services and home delivery of new and used auto parts of different late model and classic cars whose parts are not widely available in the market.\nIn countries such as the UK, the mobile car body repair sectors has experienced high growth by way of mobile SMART Repair companies providing mobile car body repair services, such as Bumper Repairs, auto body repair, paintless dent repair and paintwork defect repairs to private and commercial consumers, typically within the industry framework of refinishing vehicle damage on a localised basis, where the area of damage being repaired is not in excess of an A4 sheet of paper.", "Engineering,_Manufacturing": 0.9853998423, "qwen": "Yes"}
{"id": "25745418", "revid": "41246726", "url": "https://en.wikipedia.org/wiki?curid=25745418", "title": "Škoda-Kauba SK 257", "text": "The Škoda-Kauba Sk 257 was a Czechoslovakian-built fighter trainer monoplane built by Škoda-Kauba Flugzeugbau for the Luftwaffe.\nDevelopment.\nV4 prototypes.\nThe Škoda-Kauba Flugzeugbau produced the Škoda-Kauba V4 as a single-seat low-wing cantilever monoplane powered by a 240 hp (179 kW) Argus As 10C-3 engine with a retractable tailwheel landing gear. The first prototype proved very fast for its low power. The second included a number of changes and, despite increased power, was not as fast. A third was also completed.\nSk 257 trainer.\nThe potential for development was recognized and the German Reichsluftfahrtministerium ordered four prototypes of an enlarged aircraft with a more powerful 485 hp Argus As 410 engine and allocated the designation Sk 257. The four prototypes performed well and the type was ordered into production but the build quality of the prototypes did not pass the Luftwaffe quality control inspections and after only five production aircraft had been built the order was cancelled.\nV5 fighter project.\nEven before work on the Sk 257 began, Otto Kauba had begun work on a full-fledged fighter to have a 1,750 hp Daimler Benz DB-603 engine. Though it was in direct competition with the Focke-Wulf Ta 152, the RLM were not interested.", "Engineering,_Manufacturing": 0.9983232021, "qwen": "Yes"}
{"id": "25745688", "revid": "30707369", "url": "https://en.wikipedia.org/wiki?curid=25745688", "title": "Service chain optimization", "text": "Service chain optimization is the application of processes and tools that embrace all functions for improving the efficiency, productivity and, eventually, the profitability of service organizations.\nIn this regard, profitability of a service organization is measured by the revenue generated from service demand (in the form of service work orders being carried out), and by the costs due to activity of the enterprise's human resources (who provide the service). Service chains consider the full life-cycle of service demand from early stages of forecasting, through planning, scheduling, dispatch, execution and post-analysis.\nService chain optimization is closely related to the fields of workforce management and field service management; the activity performed by field service resources is managed through the latter while being planned and optimized through the former. This relationship is analogous to the relation between supply chain optimization and supply chain management in the domain of manufacturing. In this regard, the service chain benefits from demand forecasting, resource planning and scheduling, and long term analysis activities similarly to the manner these contribute in the supply chain (being typically managed by ERP systems and optimized by supply chain optimization systems).\nOrigin.\nThe term \"service chain optimization\" was coined by ClickSoftware in 1996. ClickSoftware received a patent, US 6.985.872 B2, for continuous planning and scheduling (service chain optimization). The term refers to field service management optimization, workforce productivity, improving customer service, and reducing operating costs.\nModules.\nMost commonly, a service chain optimization system is made up of the following units:\nThe cycle is completed by feeding the result of analysis back into the forecasting module.\nExternal links.\n\"(Links below no longer work as of Aug 2016. Highlighting so someone from Aberdeen perhaps can correct these.)\"", "Engineering,_Manufacturing": 0.9972276688, "qwen": "Yes"}
{"id": "487247", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=487247", "title": "Reuse of bottles", "text": "A reusable bottle is a bottle that can be reused, as in the case as by the original bottler or by end-use consumers. Reusable bottles have grown in popularity by consumers for both environmental and health safety reasons. Reusable bottles are one example of reusable packaging.\nHistory.\nEarly glass bottles were often reused, such as for milk, water, beer, soft drinks, yogurt, and other uses. Mason jars, for example, were developed and reused for home canning purposes.\nWith returnable bottles, a retailer would often collect empty bottles or would accept empty bottles returned by customers. Bottles would be stored and returned to the bottler in reusable cases or crates. Glass milk bottles were transported in milk crates and would be picked up by a milkman. At the bottler, the bottles would be inspected for damage, cleaned, sanitized, and refilled.\nBeginning in the second half of the 20th century, many bottles were designed for single-use, eliminating the cost of collection. This often allows for thinner glass bottles and less expensive plastic bottles and aluminum beverage cans.\nThough Sweden has had a standard glass bottle recycling system since 1884, in response to the increased litter from single-use containers, container deposit laws have been adopted in many developed countries (sometimes by provincial and municipal governments) starting in the 1970s. These laws mandate that retailers must charge a deposit on certain types of containers or for certain products; retailers are then required to accept empty bottles or cans for recycling and refund the deposit. A government fund mediates any imbalances caused by buying containers at one retailer and returning them to another, and also retains the profit from unreturned containers. Reverse vending machines are often used to automate this process. The machines scan the bar code on cans and bottles to verify that a deposit was paid, shred or crush the container for compact storage, and dispense cash or a voucher that can be redeemed at the store's checkout registers.\nIn Germany, reusable glass or plastic (PET) bottles are available for many drinks, especially beer and carbonated water as well as soft drinks (\"Mehrwegflaschen\"). The deposit per bottle (\"Pfand\") is €0.08-€0.15, compared to €0.25 for recyclable but not reusable plastic bottles. There is no deposit for glass bottles which do not get refilled, but there are many glass bottles that do get refilled - best known is the \"Normbrunnenflasche\", a 0.7l bottle used for carbonated drinks with a deposit of €0.15. It was introduced after a 1969 decision by the German mineral water industry, and more than five billion bottles have been produced used for an estimated quarter of a trillion refillings since then.\nEnvironmental consequences.\nThe reuse of containers is often thought of as being a step toward more sustainable packaging. Reuse sits high on the waste hierarchy. When a container is used multiple times, the material required per use or per filling cycle is reduced. \nMany potential factors are involved in environmental comparisons of returnable vs. non-returnable systems. Researchers have often used life cycle analysis methodologies to balance the many diverse considerations. Some comparisons show no clear winner but rather show a realistic view of a complex subject.\nArguments in favor of reusing bottles, or recycling them into other products, are compelling. It is estimated that in the U.S. alone, consumers use 1,500 plastic water bottles every single second. But only about 23% of PET plastic, which is the plastic used in disposable plastic water bottles, gets recycled. Thus, about 38 billion water bottles are thrown away annually, equating to roughly $1 billion worth of plastic. The average American spends $242 per year per person on disposable, single use plastic water bottles. The environmental and cost consequences associated with disposable plastic water bottles are a strong argument for reusing bottles.\nBottles intended for reuse by households.\nReusable drinking bottles for water, coffee, salad dressing, soup, baby formula, and other beverages have gained in popularity by consumers in recent years, due to the costs and environmental problems associated with single use plastic bottles. Common materials used to make reusable drinking bottles include glass, aluminum, stainless steel, and plastic. Reusable bottles include both single and double wall insulated bottles. Some baby bottles have an inner bag or bladder that can be replaced after each use.", "Engineering,_Manufacturing": 0.9870037436, "qwen": "Yes"}
{"id": "489295", "revid": "18779361", "url": "https://en.wikipedia.org/wiki?curid=489295", "title": "JIS encoding", "text": "In computing, JIS encoding refers to several Japanese Industrial Standards for encoding the Japanese language. Strictly speaking, the term means either:\nIn practice, \"JIS encoding\" usually refers to JIS X 0208 character data encoded with JIS X 0202. For instance, the IANA uses the codice_1 label to refer to JIS X 0202, and the codice_2 label to refer to the profile thereof defined by .\nOther encoding mechanisms for JIS characters include the Shift JIS encoding and EUC-JP. Shift JIS adds the kanji, full-width hiragana and full-width katakana from JIS X 0208 to JIS X 0201 in a backward compatible way. Shift JIS is perhaps the most widely used encoding in Japan, as the compatibility with the single-byte JIS X 0201 character set made it possible for electronic equipment manufacturers (such as cash register manufacturers) to offer an upgrade from older cheaper equipment that was not capable of displaying kanji to newer equipment while retaining character-set compatibility.\nEUC-JP is used on UNIX systems, where the JIS encodings are incompatible with POSIX standards.\nA more recent alternative to JIS coded characters is Unicode (UCS coded characters), particularly in the UTF-8 encoding mechanism.\nEncoding comparison.\nThe following table compares the features of the three main encoding schemes for JIS X 0208.", "Engineering,_Manufacturing": 0.9949576855, "qwen": "Yes"}
{"id": "47361435", "revid": "39189436", "url": "https://en.wikipedia.org/wiki?curid=47361435", "title": "Teardrop (electronics)", "text": "A teardrop is typically drop-shaped feature on a printed circuit board and can be found on the junction of vias or contact pads.\nPurpose.\nThe main purpose of teardrops is to enhance structural integrity in presence of thermal or mechanical stresses, for example due to vibration or flexing. Structural integrity may be compromised, e.g., by misalignment during drilling, so that too much copper may be removed by the drill hole in the area where a trace connects to the pad or via. An extra advantage is the enlarging of manufacturing tolerances, making manufacturing easier and cheaper.\nWhile a typical shape of a teardrop is straight-line tapering, they may be concave. This type of teardrop is also called \"filleting\" or \"straight\". To produce a \"snowman\"-shaped teardrop, a secondary pad of smaller size is added at the junction overlapping with the primary pad (hence the nickname).\nNecking.\nFor similar reasons, a technique called \"trace necking\" reduces (or \"necks down\") the width of a trace that approaches a narrower pad of a surface-mounted device or a through-hole with a diameter that is less than the width of the trace, or when the trace passes through bottlenecks (for example, between the pads of a component).", "Engineering,_Manufacturing": 0.9999791384, "qwen": "Yes"}
{"id": "5240977", "revid": "25046916", "url": "https://en.wikipedia.org/wiki?curid=5240977", "title": "IATF 16949", "text": "IATF 16949:2016 is a technical specification aimed at the development of a quality management system which provides for continual improvement, emphasizing defect prevention and the reduction of variation and waste in the automotive industry supply chain and assembly process. It is based on the ISO 9001 standard and the first edition was published in June 1999 as ISO/TS 16949:1999. IATF 16949:2016 replaced ISO/TS 16949 in October 2016.\nThe standard was prepared by the International Automotive Task Force (IATF) and the \"Technical Committee\" of ISO. It harmonises the country-specific regulations of quality management systems.\nAbout 30 percent of the more than 100 existing motorcar manufacturers follow the requirements of the norm but especially the large Asian manufacturers have differentiated and have their own requirements for the quality management systems of their corporate group and their suppliers.\nIATF 16949 applies to the design/development, production and, when relevant, installation and servicing of automotive-related products.\nThe requirements are intended to be applied throughout the supply chain. For the first time vehicle assembly plants will be encouraged to seek IATF 16949 [certification].\nHistorical background.\nMany suppliers (OEMs) were asked by the car manufacturers to build and certify their quality management system according to the rules and regulations of their own country organizations, such as:\nBut due to this regulation a supplier needed to provide two different certificates for Daimler and Chrysler (VDA 6.1 for Germany and QS 9000 America), even though the supplier delivered only to a single company. These complexities accelerated the need for harmonization.\nContents of the specification.\nThe aim of the standard is to improve the system and process quality to increase customer satisfaction, to identify problems and risks in the production process and supply chain, to eliminate their causes and to examine and take corrective and preventive measures for their effectiveness. The focus is not on the discovery, but on the avoidance of errors.\nThe ten main chapters of the standards are:\nThe process-oriented approach to business processes that is addressed in the ISO 9001:2015 is the base of the standard. It looks at the business processes in a process environment in which there are interactions and interfaces that need to be recognized, mapped and controlled by the quality management system. Additionally the gateways to the exterior (to sub-suppliers, customers and to remote locations) are defined. The Standard distinguishes between customer-oriented processes, supporting processes and management processes. This process-oriented approach is intended to improve the overview of the whole process. This is not an isolated process, but a combination of all interacting business processes which affect the quality performance of a firm.\nA key requirement of IATF 16949:2016 is the fulfillment of customer-specific requirements, set up by the automotive manufacturer in addition to the quality management system of their suppliers. This may have decisively contributed to the worldwide recognition of the IATF standard by many manufacturers.\nCertification.\nThe IATF 16949 standard can be applied throughout the supply chain in the automotive industry. Certification takes place on the basis of the certification rules issued by the International Automotive Task Force (IATF). The certificate is valid for three years and must be confirmed annually (as a minimum) by an IATF certified auditor (3rd Party Auditor) of an IATF recognized certification body. Re-certification is required at the expiry of the three-year period. Certification pursuant to IATF 16949 is intended to build up or enforce the confidence of a (potential) customer towards the system and process quality of a (potential) supplier. Today, a supplier without a valid certificate has little chance of supplying a Tier 1 supplier and certainly no chance of supplying a car manufacturer with standard parts, if indeed that OEM is a participating member of the IATF (most Japan OEM are members of JAMA and not members of the IATF).\nCertification bodies include:", "Engineering,_Manufacturing": 0.9999907017, "qwen": "Yes"}
{"id": "1182291", "revid": "17370235", "url": "https://en.wikipedia.org/wiki?curid=1182291", "title": "Design engineer", "text": "A design engineer is an engineer focused on the engineering design process in any of the various engineering disciplines (including civil, mechanical, electrical, chemical, textiles, aerospace, nuclear, manufacturing, systems, and structural /building/architectural) and design disciplines like Human-Computer Interaction.\nDesign engineers tend to work on products and systems that involve adapting and using complex scientific and mathematical techniques. The emphasis tends to be on utilizing engineering physics and other applied sciences to develop solutions for society.\nA design engineer usually works with a team of other engineers and other types of designers (e.g. industrial designers), to develop conceptual and detailed designs that ensure a product functions, performs, and is fit for its purpose. They may also work with marketers to develop the product concept and specifications to meet customer needs, and may direct the design effort. In many engineering areas, a distinction is made between the \"design engineer\" and other engineering roles (e.g. planning engineer, project engineer, test engineer). Analysis tends to play a larger role for the latter areas, while synthesis is more paramount for the former; nevertheless, all such roles are technically part of the \"overall\" engineering design process.\nWhen an engineering project involves public safety, design engineers involved are often required to be licensed - for example, as a Professional Engineer (in the U.S and Canada). There is often an \"industrial exemption\" for engineers working on project only internally to their organization, although the scope and conditions of such exemptions vary widely across jurisdictions.\nDesign engineer tasks.\nDesign engineers may work in a team along with other designers to create the drawings necessary for prototyping and production, or in the case of buildings, for construction. However, with the advent of CAD and solid modeling software, the design engineers may create the drawings themselves, or perhaps with the help of many corporate service providers.\nThe next responsibility of many design engineers is prototyping. A model of the product is created and reviewed. Prototypes are either functional or non-functional. Functional \"alpha\" prototypes are used for testing; non-functional prototypes are used for form and fit checking. Virtual prototyping and hence for any such software solutions may also be used. This stage is where design flaws are found and corrected, and tooling, manufacturing fixtures, and packaging are developed.\nOnce the \"alpha\" prototype is finalized after many iterations, the next step is the \"beta\" pre-production prototype. The design engineer, working with an industrial engineer, manufacturing engineer, and quality engineer, reviews an initial run of components and assemblies for design compliance and fabrication/manufacturing methods analysis. This is often determined through statistical process control. Variations in the product are correlated to aspects of the process and eliminated. The most common metric used is the process capability index Cpk. A Cpk of 1.0 is considered the baseline acceptance for full production go-ahead.\nThe design engineer may follow the product and make requested changes and corrections throughout the whole life of the product. This is referred to as \"cradle to grave\" engineering. The design engineer works closely with the manufacturing engineer throughout the product life cycle, and is often required to investigate and validate design changes which could lead to possible production cost reductions in order to consistently reduce the price as the product becomes mature and thus subject to discounting to defend market volumes against newer competing products. Moreover, design changes may be also made mandatory by updates in laws and regulations.\nThe design process is an information intensive one, and design engineers have been found to spend 56% of their time engaged in various information behaviours, including 14% actively searching for information. In addition to design engineers' core technical competence, research has demonstrated the critical nature of their personal attributes, project management skills, and cognitive abilities to succeed in the role.\nAmongst other more detailed findings, a recent work sampling study found that design engineers spend 62.92% of their time engaged in technical work, 40.37% in social work, and 49.66% in computer-based work. There was considerable overlap between these different types of work, with engineers spending 24.96% of their time engaged in technical and social work, 37.97% in technical and non-social, 15.42% in non-technical and social, and 21.66% in non-technical and non-social.", "Engineering,_Manufacturing": 1.0000035763, "qwen": "Yes"}
{"id": "53241228", "revid": "42727488", "url": "https://en.wikipedia.org/wiki?curid=53241228", "title": "Project production management", "text": "Project production management (PPM) is the application of operations management to the delivery of capital projects. The PPM framework is based on a project as a production system view, in which a project transforms inputs (raw materials, information, labor, plant & machinery) into outputs (goods and services).\nThe knowledge that forms the basis of PPM originated in the discipline of industrial engineering during the Industrial Revolution. During this time, industrial engineering matured and then found application in many areas such as military planning and logistics for both the First and Second World Wars and manufacturing systems. As a coherent body of knowledge began to form, industrial engineering evolved into various scientific disciplines including operations research, operations management and queueing theory, amongst other areas of focus. Project Production Management (PPM) is the application of this body of knowledge to the delivery of capital projects.\nProject management, as defined by the Project Management Institute, specifically excludes operations management from its body of knowledge, on the basis that projects are temporary endeavors with a beginning and an end, whereas operations refer to activities that are either ongoing or repetitive. However, by looking at a large capital project as a production system, such as what is encountered in construction, it is possible to apply the theory and associated technical frameworks from operations research, industrial engineering and queuing theory to optimize, plan, control and improve project performance.\nFor example, Project Production Management applies tools and techniques typically used in manufacturing management, such as described by Philip M. Morse in, or in Factory Physics to assess the impact of variability and inventory on project performance. Although any variability in a production system degrades its performance, by understanding which variability is detrimental to the business and which is beneficial, steps can be implemented to reduce detrimental variability. After mitigation steps are put in place, the impact of any residual variability can be addressed by allocating buffers at select points in the project production system – a combination of capacity, inventory and time.\nScientific and Engineering disciplines have contributed to many mathematical methods for the design and planning in project planning and scheduling, most notably linear and dynamic programming yielding techniques such as the critical path method (CPM) and the program evaluation and review technique (PERT). The application of engineering disciplines, particularly the areas of operations research, industrial engineering and queueing theory have found much application in the fields of manufacturing and factory production systems. Factory Physics is an example of where these scientific principles are described as forming a framework for manufacturing and production management.  Just as Factory Physics is the application of scientific principles to construct a framework for manufacturing and production management, Project Production Management is the application of the very same operations principles to the activities in a project, covering an area that has been conventionally out of scope for project management.\nHistorical background and related areas.\nModern project management theory and techniques started with Frederick Taylor and Taylorism/scientific management at the beginning of the 20th century, with the advent of mass manufacturing. It was refined further in the 1950s with techniques such as critical path method (CPM) and program evaluation and review technique (PERT). Use of CPM and PERT became more common as the computer revolution progressed. As the field of project management continued to grow, the role of the project manager was created and certifying organizations such as the Project Management Institute (PMI) emerged. Modern project management has evolved into a broad variety of knowledge areas described in the Guide to the Project Management Body of Knowledge (PMBOK).\nOperations management (related to the fields of production management, operations research and industrial engineering) is a field of science that emerged from the modern manufacturing industry and focuses on modeling and controlling actual work processes. The practice is based upon defining and controlling production systems, which typically consist of a series of inputs, transformational activities, inventory and outputs. Over the last 50 years, project management and operations management have been considered separate fields of study and practice.\nPPM applies the theory and results of the various disciplines known as operations management, operations research, queueing theory and industrial engineering to the management and execution of projects. By viewing a project as a production system, the delivery of capital projects can be analyzed for the impact of variability. The effects of variability can be summarized by VUT equation (specifically Kingman's formula for G/G/1 queue). By using a combination of buffers – capacity, inventory and time – the impact of variability to project execution performance can be minimized.    \nA set of key results used to analyze and optimize the work in projects were originally articulated by Philip Morse, considered the father of operations research in the U.S. and summarized in his seminal volume. In introducing its framework for manufacturing management, \"Factory Physics\" summarizes these results:\nThere are key mathematical models that describe the relationships between buffers and variability. Little's law – named after academic John Little – describes the relationship between throughput, cycle time and work-in-process (WIP) or inventory.  The Cycle Time Formula summarizes how much time a set of tasks at a particular point in a project take to execute.  Kingman's formula, also known as the VUT equation – summarizing the impact of variability.\nJournals.\nThe following academic journals publish papers pertaining to Operations Management issues:", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "65711212", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=65711212", "title": "Defected ground structure", "text": "A defected ground structure (DGS), is a purposefully created \"defect\" on the ground plane of a printed microstrip board. It is typically created in the form of an etched-out pattern on the ground plane. DGS is a simplified form of Electromagnetic Band Gap (EBG) structure. This EBG is a periodic pattern featuring a band-stop property in microstrip transmission line and circuit applications, but the DGS comprises a single defect or a very limited number of defects with periodic/aperiodic configurations.\nHistory.\nKim et al. first conceived a limited form of EBG and coined the term ‘DGS’. They used a single unit of dumbbell-shaped defect beneath a microstrip line to use its stop-band characteristics within which it impedes the propagation of electromagnetic (EM) down the line over a range of frequencies. The compact feature and ease of implementation made it popular and several other shapes of DGS evolved very fast for various microwave circuit applications. Printed circuit filter is one of them. Apart from that, DGS has also been used in the circuits of an amplifier, rat-race coupler, branch-line coupler, Wilkinson power divider, etc. DGS was also employed underneath the feed lines to integrated microstrip antenna in order to filter out any unwanted harmonics.\nIdeas for Antenna Applications.\nA new concept of its application to microstrip antenna was first reported in 2005 by Guha et al. The main focus was to suppress the cross-polarized radiations in a circular microstrip patch. DGS was strategically used to weaken the cross-pol generating higher-order TM\"21\" mode. The important and necessary condition is that the deployed DGS should not influence or disturb the main resonance, i.e. the primary radiation mode. That work indeed introduced a non-resonant DGS and proved the concept. Subsequently, several advancements both in DGS type, geometry, and cross-polar performance have been achieved.\nYet another idea of patch-DGS integration has advanced the microstrip antenna array design. The issue of mutual coupling among the array elements can be reduced by integrating simple DGS- first reported in 2006. This technique has been matured to address the practical issue of ‘Scan blindness’ of large arrays.\nThis DGS-technique has been proved to be a very useful commercially viable tool to minimize two major issues like scan blindness and cross-polar radiations in phased arrays. New generation airborne and space-borne radars are now being developed using this DGS technology.", "Engineering,_Manufacturing": 0.9994307756, "qwen": "Yes"}
{"id": "51753965", "revid": "2656885", "url": "https://en.wikipedia.org/wiki?curid=51753965", "title": "Desjardin", "text": "Desjardin is one of the longest-running French metal packaging manufacturers, founded in 1848. The company produces and exports packaging for multiple industries, including the pharmaceutical industry, the cosmetic industry or the food industry. Desjardin places emphasis on sustainable solutions for its packaging materials and its tools.\nThe company specializes in customized metal manufacturing to produce cans and tins. Many of these custom products are aluminum containers .\nHistory.\nThe Paris-based company was launched by the Desjardins family in 1848, during the formation of the French Constitution and in the middle of the industrial revolution under the name A. Desjardins. The company later changed the firm's name to \"Desjardin\". The company produced packaging that served food preservation.\nDesjardin used tin cans from its launch. It also manufactured tinware such as pots and pans. By the late nineteenth century, the company worked with film studios to provide metal cans designed to preserve 16mm and 35 mm films.\nThe company established relationships with filmmakers and has played a role in protecting film throughout the twentieth century. It provided tin for Eastman Kodak and Agfa Geveart for many years. As a partner with Laboratories Éclair, LTC, Desjardin provided movie theaters with tins as well.\nIn the 1900s Desjardin expanded the number of industries it served to include biscuits and confectionery. After moving to the Paris suburb of Gonesse in 1963, the Desjardins family continued to run the business until 1981, when current President Pierre Gachot took over. Since then Gachot has introduced new packaging automation tools, such as the Caviar box vacuum closer in 1988.\nDesjardin after 2000.\nDesjardin produces the majority of caviar tins and film tins worldwide. Beginning in the 2000s, Desjardin has partnered with several cosmetics brands and has shifted focus towards sustainable primary materials.\nVacuum packaging performed by its semi-automatic machine, the Vacuum Closing Machine (VCII), has allowed Desjardin to conserve offset printing inks.\nAs a manufacturer of packaging for the cosmetics industry, Desjardin offers containers to accommodate cream, balm, powder, oil, sprays and other cosmetics. The company commonly makes aluminum containers with screw on lids for cosmetics.\nDesjardin provides pharmaceutical packaging for products such as lipgloss, or gel. Typical containers are round with screw lids made of aluminum and metal tins. The company makes larger boxes for the food industry to package biscuits, confectionery and chocolates. They also make tin round containers for tea, coffee and spices.\nSustainability and the Environment.\nDesjardin states that they mainly use Tinplate and aluminum as primary materials due to their environmentally friendly properties of easy recycling and lack of wasteful byproducts. Desjardin has been emphasizing the environmental benefits of aluminum, which include abundance, flexibility (engineering) and durability. While aluminum manufacturers must still deal with mining, chemical and landfill issues, Desjardin encourages recycling and is participates in the debate on developing more sustainable solutions. The company argues that aluminum is both lightweight and strong, making is highly efficient with minimal damage to the environment. Aluminum helps lower both shipping costs and greenhouse gas emissions.", "Engineering,_Manufacturing": 0.9998602867, "qwen": "Yes"}
{"id": "51768040", "revid": "36659006", "url": "https://en.wikipedia.org/wiki?curid=51768040", "title": "Magnetic drilling machine", "text": "A magnetic drilling machine is a portable drilling machine with a magnetic base (either electromagnetic or permanent magnet). It can use twist drill bits, annular cutters, milling cutters, and other rotary cutters. With suitable bits it can also tap threads, ream, and countersink. Its combination of a stable magnetic base and low RPM help resist or reduce torque forces created by large diameter bits. Magnetic drilling machines with reversible motor and variable speed controls can also perform operations like tapping, countersink and reaming. Magnetic drilling machine with cross table base and can also perform light milling.\nDescription.\nA portable magnetic drilling machine is faster and more portable alternative to hole making machines such as the drill press, and is more accurate than a hand drill. \nA portable magnetic drilling machine is used on steel or other magnetic materials. It gives an accuracy of 0.01 mm to 0.05mm in steel or other magnetic material. The drill bits used for this machines are generally made from high-speed steel(HSS) or are tungsten carbide tipped(TCT).\nBase.\nThe base of a magnetic drill is equipped with a powerful electromagnet to easily clamp the machine on the work piece to be drilled. When energized this magnet is held on the metal work piece locking the machine base to the surface. The electromagnet plays a very important role in a portable magnetic drill, as it helps the machine to be steady, does not let the machine dismount during drilling, can work with the machine overhead, horizontal or vertical. Its very important that persons with heart pacemakers or other medical implants must not use this magnetic drilling machine. Generally, a magnetic core drilling machine is used on a ferrous material directly, but it can also be used on non-ferrous material like aluminum with the help of clamping devices. The new generation magnetic drilling machines' bases are also equipped with Swivel Base, to position the machine under magnetic condition.\nStand.\nA drill stand is the main body of the magnetic drill where the electric switches for motor and magnet are mounted, magnet indicator is mounted and also the clock-anticlockwise direction switches are mounted. The body of the magnetic drill holds together the motor and the magnet base. The feed handle is also attached to the body. The body of the magnetic drill helps the motor slide on it to get an upward and downward feed. The body of the magnetic drill also plays the role of a handle to lift and move the machine from one place to other. The material used for the body is generally cast iron.\nArbor.\nAn arbor or chuck on a magnetic drill is attached to the motor. it is a type of clamp used to attach the core drills. There are mainly two types of chuck available for the magnetic drill, industrial arbor (manual tightening) and quick change drill chucks. The quick change drill chucks are easy and fast option to attach the core drills. They do not need to tighten the screws/jaws manually. The arbor or chucks have different types of spindle holder (machine taper) like Morse taper MT 2, MT 3, and MT 4. The chuck allows different types of core drill shafts (shanks) to fit in it.\nTypes.\nPopular forms of magnetic drilling machine include: \nLight weight.\nVery light weight types magnetic drills are very popular to perform several operations where the weight of a machine to carry is a great concern like working on an electric pole, mobile tower, TV tower, bridge, etc.\nAutomatic and semi-automatic feed.\nMagnetic core drilling machines with fully and semi-automatic drill feed are very popular these days. These machines help in saving time and energy and resulting in more production.\nPneumatic.\nPneumatic core drilling machines are used where there is a danger of explosion or fire due to electrical sparking. The motor is driven by compressed air and the magnet is a permanent magnet instead of an electromagnet.\nCordless.\nBattery operated magnetic core drilling machines are used for a work place where there is no electricity. The motor is driven by a rechargeable battery. The magnet for these machines is either an electromagnet or a permanent magnet.\nHorizontal.\nHorizontal magnetic core drilling machines with angular gears are made for confined drilling situations.\nCross-Table Base.\nCross-table base magnetic drilling machines can also be used for light milling operations to make oval holes or key-slots. The cross-table enables the machines to move in X and Y Axis.\nPipe Drilling / Tube Drilling.\nMagnetic drilling machines having clamping system with two permanent magnets automatically which adapts to the pipe diameter.\nAnnular Cutters.\nThe magnetic core drilling machine utilizes core drills or annular cutters. \nWith a cutter wall thickness of approximately 5 mm only a small amount of material around the edge of a hole is removed by an annular cutter. Numerous teeth remain sharper longer than the single pointed tip of a spiral drill. Holes produced are smooth and burr-free - no reaming is required.\nOperation.\nDrilling holes with a magnetic drilling machine is a three-step process:\n1. The pilot pin accurately centers the cutter over the area to be drilled.\n2. During drilling, the pilot pin retracts and allows the internal lubrication to reach the cutting teeth.\n3. When the hole is complete, the slug/core is automatically ejected from the cutter, leaving an accurate, finished hole.\nHigh-quality precision-engineered cutters may have tapered inner walls. These help offset the effect of frictional heat build-up that causes expansion of both the cutter and waste slug being produced by the cutting action, allowing ready ejection of the slug upon completion.", "Engineering,_Manufacturing": 1.0000090599, "qwen": "Yes"}
{"id": "51781097", "revid": "12883001", "url": "https://en.wikipedia.org/wiki?curid=51781097", "title": "Allocacoc", "text": "Allocacoc  is an industrial design company established in the Netherlands that sells redesigned everyday products such as the PowerCube. Allocacoc headquartered in Shanghai and has a factory in Suzhou with an R&D center in Shenzhen, China. Its European head office moved from Delft to Breukelen (Utrecht) in August 2018. The company creates innovative products by adding original designs and keeping them affordable. In 2019, Allocacoc decided on a rebranding strategy and focus their business development on DesignNest.com - a consumer product platform of a broad range of design products. DesignNest was originally founded by Allocacoc in 2016 and now aiming to help industrial designers from start to finish, such as funding, design knowledge, sourcing, pricing, production, product assembly, distribution, fighting against copycats and worldwide sales.\nHistory.\nAllocacoc was founded by two industrial design engineers, Arthur Limpens and Yixia Jiang from Delft University of Technology, in the Netherlands. Stated by Yixia Jiang in a 2011 interview, the company name was inspires by their favourite drink Coca-Cola.\nProducts.\nAllocacoc has a wide range of products, including power strip, socket, light, stationary, home gadgets, audio...etc. and it is still expanding. \nAwards.\nThe PowerCube was given the Red Dot Design Award for best product design category in 2014.\nComputex Design and Innovation Award in 2015 ", "Engineering,_Manufacturing": 0.9975237846, "qwen": "Yes"}
{"id": "25351425", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=25351425", "title": "CSCMP Supply Chain Process Standards", "text": "The Council of Supply Chain Management Professionals' (CSCMP) Supply Chain Process Standards present an outline or framework for managing processes which are typically found to be involved in performing supply chain related activities, and a set of standardised activities described in two levels of maturity - the \"suggested minimum\" and \"best practice\" for each process. The standards were created for the Council of Supply Chain Management Professionals by Supply Chain Visions, a supply chain process and measures consulting firm.\nThe intent of the standards is to provide practitioners, educators and consultants with a reference tool to help companies identify potential gaps across a broad spectrum of their supply chain processes. Practitioners can use this tool to identify process strengths and weaknesses, and then focus their attention on those areas where improvement efforts will drive the most benefit. Results can be shared and compared (with discretion) with other organizations in a supply chain to improve overall effectiveness.\nThe second edition of the Standards utilizes the American Productivity & Quality Center Process Classification Framework to present the minimum and best practice attributes. The third edition was published in 2018.\nContents.\nThe standards uses a numbering scheme where each process element is referred to by categories, process groups, processes, and activities.\nFor each activity there is a description of an associated practice in two levels of maturity.\nThe Standards were compiled by Supply Chain Visions utilizing academic research, as well as on-site observations of companies\nin practice. In addition, a thorough validation process was used, where leading subject-matter experts (SMEs) in the profession reviewed and validated the accuracy of the Standards.\nCurrently in its third edition, the Standards covers a broad spectrum of supply chain processes and activities—including over 2,600 best and minimum practice statements, which is an increase of 40% over the first edition—derived from research into current cross-industry standards. To more accurately reflect today's supply chain practices, 30% of the statements in the first edition have also been revised.\nCSCMP worked with over 420 SMEs in developing the first revision of the Standards. Many of the same SMEs and many new SMEs participated in the review of the second edition of the Standards. The range of SMEs included academics, researchers, practitioners, and consultants who are widely considered experts in the field of supply chain management. The response was extraordinary. SMEs provided over 34% of the new content of the Standards, helped to revise 38% of the practice statements to make them more accurate and current, and validated the suggested minimum process standards and typical best practices descriptions in the Standards. The Standards represent a unique, broad-based, cross-industry repository of supply chain knowledge.", "Engineering,_Manufacturing": 0.99977988, "qwen": "Yes"}
{"id": "25382271", "revid": "2992972", "url": "https://en.wikipedia.org/wiki?curid=25382271", "title": "Henry W. Eastham", "text": "Henry W. Eastham was a Massachusetts businessman and politician who served as a member and President of the Common Council, and as the 30th Mayor of Lynn, Massachusetts.\nShoe machinery business.\nEastham was engaged in the manufacture of shoe manufacturing equipment, supplying the numerous shoe manufacturing companies that existed in Lynn at the time. In December 1904 Eastham sold his shoe knives and machinery business to the United Shoe Machinery Corporation. Eastham later purchased the C.W. Dodge & Co. and operated it as the Eastham Shoe Machinery and Supply Company.\nPresident of the Lynn Board of Aldermen.\nOn December 30, 1901, Eastham was chosen as President of the Lynn Board of Aldermen for 1902.", "Engineering,_Manufacturing": 1.0000070333, "qwen": "Yes"}
{"id": "25386124", "revid": "6289403", "url": "https://en.wikipedia.org/wiki?curid=25386124", "title": "Beijing Municipal Prison", "text": "Beijing Municipal Prison  is a prison in Daxing District, Beijing. \nOriginally established by the Qing dynasty on 31 March 1909, the present Daxing site was built in 1982 and the municipal prison officially moved there on 8 November 1994. It had 1600 prisoners in 2006. It is about one hour away from the centre of Beijing by car.\nIt is operated by the Beijing Municipal Administration of Prisons.\n it houses almost 2,000 male inmates; these inmates are sentenced to 15 or more years, and criminals with special circumstances. It has 18 workshops including an auto manufacturing plant, a plastic packaging plant and a steel factory. Produces light steel, construction templates, paper products, automobile remodeling, spray paint, spray molding, clothing and toys. Inmates use metal cutting lathes, shears, bending machines, straight cutting machines, assembly machines, flange straightening machines, arc welding generators, sewing machines, and other equipment.", "Engineering,_Manufacturing": 0.9995372295, "qwen": "Yes"}
{"id": "9062408", "revid": "5320876", "url": "https://en.wikipedia.org/wiki?curid=9062408", "title": "Bulk bins", "text": "Bulk bins are a way of selling consumables by weight. The product is stored in bins in a section of the retail floor. A customer can measure out an amount of product into a plastic bag, to be later weighed at the point of sale. The product is usually less expensive per unit compared to pre-packaged items. The customer is able to choose exactly how much product they want and will go home with less packaging.\nProducts compatible with bulk bin selling are:\nTraditional bulk bins were typically wooden barrels, or burlap sacks the food products came in, and from which the customer would shop. These traditional methods of dispensing were cheap, and did not protect the food products from open air environments which allowed the accelerated spoilage of food, and created the potential for outside contaminants to affect the food.\nToday, bulk bins are made of polycarbonate, or BPA-free resins which display the food product, and provide an airtight, hygienic system for dispensing foods.\nPerishable or bulky items usually are not sold in this way.", "Engineering,_Manufacturing": 0.9973887205, "qwen": "Yes"}
{"id": "27456331", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=27456331", "title": "Sheet metal forming analysis", "text": "For sheet metal forming analysis within the metal forming process, a successful technique requires a non-contact optical 3D deformation measuring system. The system analyzes, calculates and documents deformations of sheet metal parts, for example. It provides the 3D coordinates of the component's surface as well as the distribution of major and minor strain on the surface and the material thickness reduction. In the Forming Limit Diagram, the measured deformations are compared to the material characteristics. The system supports optimization processes in sheet metal forming by means of;\nThe optical forming analysis with Forming analysis system provides for precise and fast measurement of small and large components using a high scanning density. Forming analysis system operates independently of the material. It can analyze components made from flat blanks, tubes or other components manufactured by an internal high pressure forming process (IHPF, Hydro forming).\nFunctional principle explained by means of a standard measuring project.\nThe forming analysis system compares the 3D positions of measuring points in a flat and in a deformed state.\nPrior to the deformation, a regular point pattern is applied to the surface of the measuring object. For measuring objects which undergo high friction during the forming process, the measuring points are applied, for example, with the help of electrolytic methods. After the forming process of the measuring object, a camera (online or stand-alone operation) records the measuring points in several different images with different views.\nForming analysis system works with two point types.\nIn the Forming analysis system, the 3D computation of the measuring points is done using photogrammetric methods. For the automatic spatial orientation of the individual images or views, coded points are position close to or on the measuring object.\nThe basic idea of Photogrammetry is to look at points (coded and uncoded) from different directions and to calculate the 3D coordinates of these points from the images or point rays thus obtained. The points visible in an image have a fixed relation to each other. Therefore, by means of images made from other angles of view, it is possible to calculate the camera location using this point relation. During the acquisition of an image set it is the goal to record points from multiple different directions that show the largest possible angles (A, B, C) to each other.\nIt is the task of the Forming analysis system software to precisely find ellipses (a perspective view of point surfaces) in all images of the image set and their 3D orientation. The Forming analysis system software interprets the images and generates 3D measuring data.\nIn order to compute the strain, the flat state is compared to the deformed state. (#1 & #2)\nIn a standard measuring project, the flat state, the strain reference, is not captured optically but results from the theoretical point distance defined in the project parameters.\nAs a default, Forming analysis system presumes an exactly regular initial pattern which is on one plane and for which the point distance is known. This is called the \"virtual reference stage\" and is marked with Stage 0 in italic letters in the software. All strain values refer to the adjusted computation parameter Point distance.\nThe Forming analysis system software is also capable of analyzing several static deformation states (stages) within one project where each deformation stage can be set as strain reference any time. This procedure may be used, for example, for the deformation analysis of tubes.\nTo allow for a full-field view of the strain, the software changes to the so-called grid mode (#3 & #4). This means that based on the center points of the measuring points a grid surface is created. Each grid line intersection point represents a 3D measuring point. The full-field color representation of the strain results from the 3D positions of these grid line intersection points. (#5 & #6)", "Engineering,_Manufacturing": 0.9999945164, "qwen": "Yes"}
{"id": "55507154", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=55507154", "title": "Solder fatigue", "text": "Solder fatigue is the mechanical degradation of solder due to deformation under cyclic loading. This can often occur at stress levels below the yield stress of solder as a result of repeated temperature fluctuations, mechanical vibrations, or mechanical loads. Techniques to evaluate solder fatigue behavior include finite element analysis and semi-analytical closed-form equations.\nOverview.\nSolder is a metal alloy used to form electrical, thermal, and mechanical interconnections between the component and printed circuit board (PCB) substrate in an electronic assembly. Although other forms of cyclic loading are known to cause solder fatigue, it has been estimated that the largest portion of electronic failures are thermomechanically driven due to temperature cycling. Under thermal cycling, stresses are generated in the solder due to coefficient of thermal expansion (CTE) mismatches. This causes the solder joints to experience non-recoverable deformation via creep and plasticity that accumulates and leads to degradation and eventual fracture.\nHistorically, tin-lead solders were common alloys used in the electronics industry. Although they are still used in select industries and applications, lead-free solders have become significantly more popular due to RoHS regulatory requirements. This new trend increased the need to understand the behavior of lead-free solders.\nMuch work has been done to characterize the creep-fatigue behavior of various solder alloys and develop predictive life damage models using a Physics of Failure approach. These models are often used when trying to assess solder joint reliability. The fatigue life of a solder joint depends on several factors including: the alloy type and resulting microstructure, the joint geometry, the component material properties, the PCB substrate material properties, the loading conditions, and the boundary conditions of the assembly.\nThermomechanical solder fatigue.\nDuring a product's operational lifetime it undergoes temperature fluctuations from application specific temperature excursions and self-heating due to component power dissipation. Global and local mismatches of coefficient of thermal expansion (CTE) between the component, component leads, PCB substrate, and system level effects drive stresses in the interconnects (i.e. solder joints). Repeated temperature cycling eventually leads to thermomechanical fatigue.\nThe deformation characteristics of various solder alloys can be described at the microscale due to the differences in composition and resulting microstructure. Compositional differences lead to variations in phase(s), grain size, and intermetallics. This affects susceptibility to deformation mechanisms such as dislocation motion, diffusion, and grain boundary sliding. During thermal cycling, the solder's microstructure (grains/phases) will tend to coarsen as energy is dissipated from the joint. This eventually leads to crack initiation and propagation which can be described as accumulated fatigue damage.\nThe resulting bulk behavior of solder is described as viscoplastic (i.e. rate dependent inelastic deformation) with sensitivity to elevated temperatures. Most solders experience temperature exposures near their melting temperature (high homologous temperature) throughout their operational lifetime which makes them susceptible to significant creep. Several constitutive models have been developed to capture the creep characteristics of lead and lead-free solders. Creep behavior can be described in three stages: primary, secondary, and tertiary creep. When modeling solder, secondary creep, also called steady state creep (constant strain rate), is often the region of interest for describing solder behavior in electronics. Some models also incorporate primary creep. Two of the most popular models are hyperbolic sine models developed by Garofalo and Anand to characterize the steady state creep of solder. These model parameters are often incorporated as inputs in FEA simulations to properly characterize the solder response to loading.\nFatigue models.\nSolder damage models take a physics-of-failure based approach by relating a physical parameter that is a critical measure of the damage mechanism process (i.e. inelastic strain range or dissipated strain energy density) to cycles to failure. The relationship between the physical parameter and cycles to failure typically takes on a power law or modified power law relationship with material dependent model constants. These model constants are fit from experimental testing and simulation for different solder alloys. For complex loading schemes, Miner's linear superposition damage law is employed to calculate accumulated damage.\nCoffin–Manson model.\nThe generalized Coffin–Manson model considers the elastic and plastic strain range by incorporating Basquin's equation and takes the form:\nformula_1\nHere \"∆ε\" ⁄ 2 represents the elastic-plastic cyclic strain range, \"E\" represents elastic modulus, \"σm\" represents means stress, and \"Nf\" represents cycles to failure. The remaining variables, namely \"σf\",\"ε'f\",\"b\",and \"c\" are fatigue coefficients and exponents representing material model constants. The generalized Coffin–Manson model accounts for the effects of high cycle fatigue (HCF) primarily due to elastic deformation and low cycle fatigue (LCF) primarily due to plastic deformation.\nEngelmaier model.\nIn the 1980s Engelmaier proposed a model, in conjunction with the work of Wild, that accounted for some of the limitations of the Coffin–Manson model, such as the effects of the frequency and temperature. His model takes a similar power law form:\nformula_2\nformula_3\nEngelmaier relates the total shear strain (∆γ) to cycles to failure (\"Nf\"). \"ε'f\" and \"c\" are model constants where \"c\" is a function of mean temperature during thermal cycling (\"Ts\") and thermal cycling frequency (\"f\").\nformula_4\n∆γ can be calculated as function of the distance from the neutral point (\"LD\") solder joint height (\"hs\"), coefficient of thermal expansion (∆\"α\"), and change in temperature (Δ\"T\"). In this case \"C\" is empirical model constant.\nThis model was initially proposed for leadless devices with tin-lead solder. The model has since been modified by Engelmaier and others to account for other phenomena such as leaded components, thermal cycling dwell times, and lead-free solders. While initially a substantial improvement over other techniques to predict solder fatigue, such as testing and simple acceleration transforms, it is now generally acknowledged that Engelmaier and other models that are based on strain range do not provide a sufficient degree of accuracy.\nDarveaux model.\nDarveaux proposed a model relating the quantity of volume weighted average inelastic work density, the number of cycles to crack initiation, and the crack propagation rate to the characteristic cycles to failure.\nformula_5\nformula_6\nformula_7\nIn the first equation \"N0\" represents the number of cycles to crack initiation, ∆W represents inelastic work density, \"K1\" and \"K2\" are material model constants. In the second equation, da/dN represents the crack prorogation rate, ∆W represents inelastic work density, \"K3\" and \"K4\" are material model constants. In this case the crack propagation rate is approximated to be constant. \"Nf\" represents the characteristic cycles to failure and a represents the characteristic crack length. Model constants can be fit for different solder alloys using a combination of experimental testing and Finite Element Analysis (FEA) simulation.\nThe Darveaux model has been found to be relatively accurate by several authors. However, due to the expertise, complexity, and simulation resources required, its use has been primarily limited to component manufacturers evaluating component packaging. The model has not received acceptance in regards to modeling solder fatigue across an entire printed circuit assembly and has been found to be inaccurate in predicting system-level effects (triaxiality) on solder fatigue.\nBlattau model.\nThe current solder joint fatigue model preferred by the majority of electronic OEMs worldwide is the Blattau model, which is available in the Sherlock Automated Design Analysis software. The Blattau model is an evolution of the previous models discussed above. Blattau incorporates the use of strain energy proposed by Darveaux, while using closed-form equations based on classic mechanics to calculate the stress and strain being applied to the solder interconnect. An example of these stress/strain calculations for a simple leadless chip component is shown in the following equation:\nformula_8\nHere α is the CTE, T is temperature, \"LD\" is the distance to the neutral point, E is elastic modulus, A is the area, h is the thickness, G is shear modulus, ν is Poisson's ratio, and a is the edge length of the copper bond pad. The subscripts 1 refer to the component, 2 and b refer to the board, and s refer to the solder joint. The shear stress (∆τ) is then calculated by dividing this calculated force by the effective solder joint area. Strain energy is computed using the shear strain range and shear stress from the following relationship:\nformula_9\nThis approximates the hysteresis loop to be roughly equilateral in shape. Blattau uses this strain energy value in conjunction with models developed by Syed to relate dissipated strain energy to cycles to failure.\nOther fatigue models.\nThe Norris–Landzberg model is a modified Coffin–Manson model.\nAdditional strain range and strain energy based models have been proposed by several others.\nVibration and cyclic mechanical fatigue.\nWhile not as prevalent as thermomechanical solder fatigue, vibration fatigue and cyclic mechanical fatigue are also known to cause solder failures. Vibration fatigue is typically considered to be high cycle fatigue (HCF) with damage driven by elastic deformation and sometimes plastic deformation. This can depend on the input excitation for both harmonic and random vibration. Steinberg developed a vibration model to predict time to failure based on the calculated board displacement. This model takes into account the input vibration profile such as the power spectral density or acceleration time history, the natural frequency of the circuit card, and the transmissibility. Blattau developed a modified Steinberg model that uses board level strains rather than displacement and has sensitivity to individual package types.\nAdditionally, low-temperature isothermal mechanical cycling is typically modeled with a combination of LCF and HCF strain range or strain energy models. The solder alloy, assembly geometry and materials, boundary conditions, and loading conditions will affect whether fatigue damage is dominated by elastic (HCF) or plastic (LCF) damage. At lower temperatures and faster strain rates the creep can approximated to be minimal and any inelastic damage will be dominated by plasticity. Several strain range and strain energy models have been employed in this type of a case, such as the Generalized Coffin–Manson model. In this case, much work has been done to characterize the model constants of various damage models for different alloys.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "30862921", "revid": "159620", "url": "https://en.wikipedia.org/wiki?curid=30862921", "title": "Roll forming", "text": "Roll forming, also spelled roll-forming or rollforming, is a type of rolling involving the continuous bending of a long strip of sheet metal (typically coiled steel) into a desired cross-section. The strip passes through sets of rolls mounted on consecutive stands, each set performing only an incremental part of the bend, until the desired cross-section (profile) is obtained. Roll forming is ideal for producing constant-profile parts with long lengths and in large quantities.\nOverview.\nA variety of cross-section profiles can be produced, but each profile requires a carefully crafted set of roll tools. Design of the rolls starts with a \"flower pattern\", which is the sequence of profile cross-sections, one profile for each stand of rolls. The roll contours are then derived from the flower pattern profiles. Because of the high cost of the roll sets, computer simulation is often used to develop or validate the roll designs and optimize the forming process to minimize the number of stands and material stresses in the final product.\nRoll-formed sections may have advantages over extrusions of a similar shapes. Roll formed parts may be much lighter, with thinner walls possible than in the extrusion process, and stronger, having been work hardened in a cold state. Parts can be made having a finish or already painted. In addition, the roll forming process is more rapid and takes less energy than extrusion.\nRoll forming machines are available that produce shapes of different sizes and material thicknesses using the same rolls. Variations in size are achieved by making the distances between the rolls variable by manual adjustment or computerized controls, allowing for rapid changeover. These specialized mills are prevalent in the light gauge framing industry where metal studs and tracks of standardized profiles and thicknesses are used. For example, a single mill may be able to produce metal studs of different web (e.g. 3-5/8\" to 14 inches), flange (e.g. 1-3/8\" to 2-1/2\") and lip (e.g. 3/8\" to 5/8\") dimensions, from different gauges (e.g. 20 to 12 GA) of galvanized steel sheet.\nRoll forming lines can be set up with multiple configurations to punch and cut off parts in a continuous operation. For cutting a part to length, the lines can be set up to use a pre-cut die where a single blank runs through the roll mill, or a post-cut die where the profile is cut off after the roll forming process. Features may be added in a hole, notch, embossment, or shear form by punching in a roll forming line. These part features can be done in a pre-punch application (before roll forming starts), in a mid-line punching application (in the middle of a roll forming line/process) or a post punching application (after roll forming is done). Some roll forming lines incorporate only one of the above punch or cut off applications, others incorporate some or all of the applications in one line.\nProcess.\nRoll forming is, among the manufacturing processes, one of the simplest. It typically begins with a large coil of sheet metal, between and in width, and and thick, supported on an uncoiler. The strip is fed through an entry guide to properly align the material as it passes through the rolls of the mill, each set of rolls forming a bend until the material reaches its desired shape. Roll sets are typically mounted one over the other on a pair of horizontal parallel shafts supported by a stand(s). Side rolls and cluster rolls may also be used to provide greater precision and flexibility and to limit stresses on the material. The shaped strips can be cut to length ahead of a roll forming mill, between mills, or at the end of the roll forming line.\nGeometric possibilities.\nThe geometric possibilities can be very broad and even include enclosed shapes as long as the cross-section is uniform. Typical sheet thicknesses range from to , but they can exceed that. Length is almost unaffected by the rolling process. The part widths typically are not smaller than however they can exceed . The primary limitation is profile depth, which is generally limited to less than and rarely larger than due to roll-imparted stresses and surface speed differentials that increase with depth.\nProduction rates.\nThe production rate depends greatly on the material thickness and the bend radius; it is however also affected by the number of required stations or steps. For bend radii of 50 times the material thickness of a low carbon steel thick can range from through eight stations to through 12 stations or through 22 stations.\nThe time for one product to take shape can be represented by a simple function: , where is the length of the piece being formed, is the number of forming stands, is the distance between stands, and is the velocity of the strip through the rolls.\nIn general, roll forming lines can run from or higher, depending on the application. In some cases the limiting factor is the punching or cut-off applications.\nOther considerations.\nWhile dealing with manufacturing, Things to consider are, for example, lubrication, the effect of the process on material properties, cost, and of course safety.\nLubrication provides an essential barrier between the roll dies and the work-piece surface. It helps reducing the tool wear and allows things to move along faster. This table shows the different kinds of lubricants, their application, and the ideal metals to use them on.\nThe effects of the process on the material's properties are minimal. The physical and chemical properties virtually don't change, but the process may cause work-hardening, micro-cracks, or thinning at bends when discussing the mechanical properties of the material.\nThe cost of roll forming is relatively low. When calculating the cost of the process things such as setup time, equipment and tool costs, load/unload time, direct labor rate, overhead rate, and the amortization of equipment and tooling must be considered.Safety is also a bit of an issue with this process. The main hazards that need to be taken into consideration are dealing with moving work-pieces (up to ), high pressure rolls, or sharp, sheared metal edges.", "Engineering,_Manufacturing": 1.000007391, "qwen": "Yes"}
{"id": "30863734", "revid": "6908984", "url": "https://en.wikipedia.org/wiki?curid=30863734", "title": "Metal spinning", "text": "Metal spinning, also known as spin forming or spinning or metal turning most commonly, is a metalworking process by which a disc or tube of metal is rotated at high speed and formed into an axially symmetric part. Spinning can be performed by hand or by a CNC lathe.\nThe metal spinning trade is one that dates back to antiquity and was a skill used in the Ancient Egyptian era. This is when metal spinning was limited to soft metals spun by human power on primitive lathes. The technique gave significant advances to hydro and steam power in Europe and North America in the 19th century and by the early 20th century the electric motor provided the necessary power and high-speed turning capability. With this advancement, metal spinning craftsmen were now able to spin higher quality pieces made out of brass, copper, aluminum and even stainless and cold-rolled steel.\nMetal spinning does not involve removal of material, as in conventional wood or metal turning, but forming (moulding) of sheet metal over an existing shape.\nMetal spinning ranges from an artisan's specialty to the most advantageous way to form round metal parts for commercial applications. Artisans use the process to produce architectural detail, specialty lighting, decorative household goods and urns. Commercial applications include rocket nose cones, cookware, gas cylinders, brass instrument bells, and public waste receptacles. Virtually any ductile metal may be formed, from aluminum or stainless steel, to high-strength, high-temperature alloys including INX, Inconel, Grade 50 / Corten, and Hastelloy. The diameter and depth of formed parts are limited only by the size of the equipment available.\nProcess.\nThe spinning process is fairly simple. A formed block is mounted in the drive section of a lathe. A pre-sized metal disk is then clamped against the block by a pressure pad, which is attached to the tailstock. The block and workpiece are then rotated together at high speeds. A localized force is then applied to the workpiece to cause it to flow over the block. The force is usually applied via various levered tools. Simple workpieces are just removed from the block, but more complex shapes may require a multi-piece block. Extremely complex shapes can be spun over ice forms, which then melt away after spinning. Because the final diameter of the workpiece is always less than the starting diameter, the workpiece must thicken, elongate radially, or buckle circumferentially.\nA more involved process, known as \"reducing\" or \"necking\", allows a spun workpiece to include reentrant geometries. If surface finish and form are not critical, then the workpiece is \"spun on air\"; no mandrel is used. If the finish or form are critical then an eccentrically mounted mandrel is used.\n\"Hot spinning\" involves spinning a piece of metal on a lathe while high heat from a torch is applied to the workpiece. Once heated, the metal is then shaped as the tool on the lathe presses against the heated surface forcing it to distort as it spins. Parts can then be shaped or necked down to a smaller diameter with little force exerted, providing a seamless shoulder.\nTools.\nThe basic hand metal spinning tool is called a \"spoon\", though many other tools (be they commercially produced, ad hoc, or improvised) can be used to effect varied results. Spinning tools can be made of hardened steel for use with aluminum, or from solid brass for spinning stainless steel or mild steel.\nSome metal spinning tools are allowed to spin on bearings during the forming process. This reduces friction and heating of the tool, extending tool life and improving surface finish. Rotating tools may also be coated with a thin film of ceramic to prolong tool life. Rotating tools are commonly used during CNC metal spinning operations.\nCommercially, rollers mounted on the end of levers are generally used to form the material down to the mandrel in both hand spinning and CNC metal spinning. Rollers vary in diameter and thickness depending the intended use. The wider the roller the smoother the surface of the spinning; the thinner rollers can be used to form smaller radii.\nCutting of the metal is done by hand held cutters, often foot long hollow bars with tool steel shaped/sharpened files attached. In CNC applications, carbide or tool steel cut-off tools are used.\nThe mandrel does not incur excessive forces, as found in other metalworking processes, so it can be made from wood, plastic, or ice. For hard materials or high volume use, the mandrel is usually made of metal.\nAdvantages and disadvantages.\nSeveral operations can be performed in one set-up. Work pieces may have re-entrant profiles and the profile in relation to the center line virtually unrestricted.\nForming parameters and part geometry can be altered quickly, at less cost than other metal forming techniques. Tooling and production costs are also comparatively low. Spin forming, often done by hand, is easily automated and an effective production method for prototypes as well as high quantity production runs.\nOther methods of forming round metal parts include hydroforming, stamping, forging and casting. These other methods generally have a higher fixed cost, but a lower variable cost than metal spinning. As machinery for commercial applications has improved, parts are being spun with thicker materials in excess of 1in (25mm) thick steel. Conventional spinning also wastes a considerably smaller amount of material than other methods.\nObjects can be built using one piece of material to produce parts without seams. Without seams, a part can withstand higher internal or external pressure exerted on it. For example: scuba tanks and CO2 cartridges.\nOne disadvantage of metal spinning is that if a crack forms or the object is dented, it must be scrapped. Repairing the object is not cost-effective.\nExternal links.\nhttps://www.metalcraftspinning.com/metal-spinning/", "Engineering,_Manufacturing": 1.0000016689, "qwen": "Yes"}
{"id": "404292", "revid": "8035165", "url": "https://en.wikipedia.org/wiki?curid=404292", "title": "Orient Watch", "text": " is a Japanese watch manufacturer founded in 1950. Established as an independent company in 1950, it became a functional subsidiary of Epson in 2009 before being fully integrated into the company in 2017.\nUntil it was absorbed into Epson, the Orient Watch Company had primarily marketed mechanical watches (self-winding & hand-winding), but also produced quartz, light-powered (solar) and radio-controlled models. Outside of the main business, the company produced some moving parts and electronic components that were then assembled into Seiko Epson's electronic devices.\nCurrently, Akita Epson Corporation (formally Akita Orient Precision Instruments Co., Ltd.), a group company of Epson, manufactures all of the Orient movements in-house in Yuzawa, Akita, Japan.\nHistory.\nThe origin of Orient Watch Company dates back to 1901 when Shogoro Yoshida opened a wholesale shop called \"Yoshida Watch Shop\" in Ueno, Taito, Tokyo, Japan. Yoshida Watch Shop was successful, selling imported pocketwatches. In 1912, Yoshida expanded his business and began producing gold wristwatch cases. In 1920, Toyo Tokei Manufacturing was established, originally producing table clocks and gauges. It was not until 1934 that Toyo Tokei Manufacturing started the production of wristwatches. In 1936, the Hino factory was built in Hino, Tokyo, Japan. For several years, Toyo Tokei Manufacturing boomed at the Hino factory. However, the company shut down in 1949 in the Japanese economic devastation following World War II.\nAfter Toyo Tokei Manufacturing was shut down, Yoshida's wristwatch manufacturing company was reborn in 1950, founded under the name Tama Keiki Company. Tama Keiki Co. continued manufacturing watches at the Hino factory. In 1951, Tama Keiki Co. changed its name to , and in the same year the first Orient Star went on sale. Orient Watch was able to expand their visibility overseas after a memorandum trade agreement with China in 1955. The Royal Orient went on sale in 1960. Other important watches in the company's history include the \"Dynamic\" in 1956, \"Grand Prix 100\" in 1964, \"Fineness\" (the world's thinnest automatic wristwatch with day and date calendar function for its time) in 1967, and the \"Tenbeat\" in 1970.\nIn 2003, the Orient Technical Center (OTC) was established and the assembly of luxury watches began in Ugo, Ogachi, Akita, Japan. In 2004, the high-precision caliber 88700 movement went on sale via the Royal Orient watch line. In 2005, Orient Star Retro-Future collection was launched. In 2010, Orient Watch Co. celebrated its 60th anniversary with a limited edition model. The Royal Orient line was discontinued around 2016, likely to prevent cannibalism between it and fellow Seiko group brands Grand Seiko, and Credor. To celebrate 70 years of the Orient Star line, the Orient Star skeleton watch was introduced with a silicon escapement made using Epson's MEMS technology, which has been used in high end Seiko watches since 2009.\nIn 2001 Seiko Epson (one of three core companies of the Seiko Group) became the majority shareholder (52%) of the company. Orient Watch became a wholly owned subsidiary of Epson in 2009. After transferring its business to Epson, the company now exists as a dormant company. Epson Sales Japan Corporation markets the Orient watches, while Akita Epson Corporation manufactures them.", "Engineering,_Manufacturing": 0.993033886, "qwen": "Yes"}
{"id": "29928760", "revid": "23646674", "url": "https://en.wikipedia.org/wiki?curid=29928760", "title": "Highly accelerated stress audit", "text": "HASA (highly accelerated stress audit) is a proven test method developed to find manufacturing/production process induced defects in electronics and electro-mechanical assemblies before those products are released to market. HASA is a form of HASS (highly accelerated stress screening) – a powerful testing tool for improving product reliability, reducing warranty costs and increasing customer satisfaction.\nSince HASS levels are more aggressive than conventional screening tools, a POS procedure is used to establish the effectiveness in revealing production induced defects. A POS is vital to determine that the HASS stresses are capable of revealing production defects, but not so extreme as to remove significant life from the test item. Instituting HASS to screen the product is an excellent tool to maintain a high level of robustness and it will reduce the test time required to screen a product resulting in long term savings. Ongoing HASS screening assures that any weak components or manufacturing process degradations are quickly detected and corrected. HASS is not intended to be a rigid process that has an endpoint. It is a dynamic process that may need modification or adjustment over the life of the product.\nHASS aids in the detection of early life failures. HASA's primary purpose is to monitor manufacturing and prevent any defects from being introduced during the process. A carefully determined HASA sampling plan must be designed that will quickly signal when process quality has been degraded.", "Engineering,_Manufacturing": 1.0000089407, "qwen": "Yes"}
{"id": "3202672", "revid": "10951369", "url": "https://en.wikipedia.org/wiki?curid=3202672", "title": "DELMIA", "text": "Dassault Systèmes DELMIA is a Global Industrial Operations software that specializes in digital manufacturing and manufacturing simulation.\nThe acronym DELMIA means: Digital Enterprise Lean Manufacturing Interactive Application", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "3203285", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=3203285", "title": "Solder paste", "text": "Solder paste is used in the manufacture of printed circuit boards to connect surface mount components to pads on the board. It is also possible to solder through-hole pin in paste components by printing solder paste in and over the holes. The sticky paste temporarily holds components in place; the board is then heated, melting the paste and forming a mechanical bond as well as an electrical connection. The paste is applied to the board by jet printing, stencil printing or syringe; then the components are put in place by a pick-and-place machine or by hand.\nUse.\nA majority of the defects in circuit-board assembly are caused due to issues in the solder-paste printing process or due to defects in the solder paste. There are many different types of defects possible, e.g. too much solder, or the solder melts and connects too many wires (bridging), resulting in a short circuit. Insufficient amounts of paste result in incomplete circuits. Head-in-pillow defects, or incomplete coalescence of ball grid array (BGA) sphere and solder paste deposit, is a failure mode that has seen increased frequency since the transition to lead-free soldering. Often missed during inspection, a head-in-pillow (HIP) defect appears like a head resting on a pillow with a visible separation in the solder joint at the interface of the BGA sphere and reflowed paste deposit. An electronics manufacturer needs experience with the printing process, specifically the paste characteristics, to avoid costly re-work on the assemblies. The paste's physical characteristics, like viscosity and flux levels, need to be monitored periodically by performing in-house tests.\nWhen making PCBs (printed circuit boards), manufacturers often test the solder paste deposits using SPI (solder paste inspection). SPI systems measure the volume of the solder pads before the components are applied and the solder melted. SPI systems can reduce the incidence of solder-related defects to statistically insignificant amounts. Inline systems are manufactured by various companies such as Delvitech (Switzerland), Sinic-Tek (China), Koh Young (Korea), GOEPEL electronic (Germany), CyberOptics (US), Parmi (Korea) and Test Research, Inc. (Taiwan). Offline systems are manufactured by various companies such as by VisionMaster, Inc. (US) and Sinic-Tek (China).\nComposition.\nA solder paste is essentially powdered solder suspended in flux paste. The tackiness of the flux holds components in place until the soldering reflow process melts the solder. As a result of environmental legislation, most solders today, including solder pastes, are made of lead-free alloys.\nClassification.\nBy size.\nThe size and shape of the metal particles in the solder paste determines how well the paste will \"print\". A solder ball is spherical in shape; this helps in reducing surface oxidation and ensures good joint formation with the adjoining particles. Irregular particle sizes are not used, as they tend to clog the stencil, causing printing defects. To produce a quality solder joint, it's very important for the spheres of metal to be very regular in size and have a low level of oxidation.\nSolder pastes are classified based on the particle size by IPC standard J-STD 005. The table below shows the classification type of a paste compared with the mesh size and particle size. Some suppliers use propriety particle size descriptions, Henkel/Loctite descriptions are given for comparison.\nBy flux.\nAccording to IPC standard J-STD-004 \"Requirements for Soldering Fluxes\", solder pastes are classified into three types based on the flux types:\nRosin based fluxes are made with rosin, a natural extract from pine trees. These fluxes can be cleaned if required after the soldering process using a solvent (potentially including chlorofluorocarbons) or saponifying flux remover.\nWater-soluble fluxes are made up of organic materials and glycol bases. There is a wide variety of cleaning agents for these fluxes.\nA no-clean flux is designed to leave only small amounts of inert flux residues. No-clean pastes save not only cleaning costs, but also capital expenditures and floor space. However, these pastes need a very clean assembly environment and may need an inert reflow environment.\nProperties of solder paste.\nIn using solder paste for circuit assemblies, one needs to test and understand the various rheological properties of a solder paste.\nUse.\nSolder paste is typically used in a stencil-printing process by a solder paste printer, in which paste is deposited over a stainless steel or polyester mask to create the desired pattern on a printed circuit board. The paste may be dispensed pneumatically, by pin transfer (where a grid of pins is dipped in solder paste and then applied to the board), or by jet printing (where the paste is ejected onto the pads through nozzles, like an inkjet printer).\nAs well as forming the solder joint itself, the paste carrier/flux must have sufficient tackiness to hold the components while the assembly passes through the various manufacturing processes, perhaps moved around the factory.\nPrinting is followed by a complete reflow soldering process.\nThe paste manufacturer will suggest a suitable reflow temperature profile to suit their individual paste. The main requirement is a gentle rise in temperature to prevent explosive expansion (which can cause \"solder balling\"), yet activate the flux. Thereafter, the solder melts. The time in this area is known as \"Time Above Liquidus\". A reasonably rapid cool-down period is required after this time.\nFor a good soldered joint, the proper amount of solder paste must be used. Too much paste may result in a short circuit; too little may result in poor electrical connection or physical strength. Although solder paste typically contains around 90% metal in solids by weight, the volume of the soldered joint is only about half that of the solder paste applied. This is due to the presence of flux and other non-metallic agents in the paste, and the lower density of the metal particles when suspended in the paste as compared to the final, solid alloy.\nAs with all fluxes used in electronics, residues left behind may be harmful to the circuit, and standards (e.g., J-std, JIS, IPC) exist to measure the safety of the residues left behind.\nIn most countries, \"no-clean\" solder pastes are the most common; in the United States, water-soluble pastes (which have compulsory cleaning requirements) are common.\nStorage.\nSolder paste must be refrigerated when transported and stored in an airtight container at a temperature between 0-10 °C. It should be warmed to room temperature for use.\nRecently, new solder pastes have been introduced that remain stable at 26.5 °C for one year and at 40 °C for one month.\nExposure of the solder particles, in their raw powder form, to air causes them to oxidize, so exposure should be minimized.\nEvaluation.\nThe main reason why evaluation of solder paste is necessary, is because 50-90% of all defects result from printing problems. Hence, paste evaluation is critical.\nThis procedure is quite thorough, yet minimizes the amount of testing required to differentiate between excellent and poor solder pastes. If multiple solder pastes are evaluated, the procedure can be used to eliminate the poor pastes from their poor printing quality. Further testing, such as solder reflow performance, solder joint quality, and reliability testing can then be performed on the solder paste finalists.\nConcerns.\nThe main concerns about solder paste are:\nThese three concerns helped to spawn three enclosed systems for printing.", "Engineering,_Manufacturing": 1.0000078678, "qwen": "Yes"}
{"id": "20579385", "revid": "40276288", "url": "https://en.wikipedia.org/wiki?curid=20579385", "title": "Demand flow technology", "text": "Demand Flow Technology (DFT) is a strategy for defining and deploying business processes in a flow, driven in response to customer demand. DFT is based on a set of applied mathematical tools that are used to connect processes in a flow and link it to daily changes in demand.\nDFT represents a scientific approach to flow manufacturing for discrete production. It is built on principles of demand pull where customer demand is the central signal to guide factory and office activity in the daily operation. DFT is intended to provide an alternative to schedule-push manufacturing which primarily uses a sales plan and forecast to determine a production schedule.\nHistory.\nIt was created by John R. Costanza, an executive with operations management experience at Hewlett Packard and Johnson & Johnson. Costanza, who was later nominated as a Nobel Laureate in Economics for Working Capital Management, founded the John Costanza Institute of Technology in Englewood, CO in 1984 to provide consulting and education services for manufacturers to implement the methodology.\nDFT uses applied mathematical methods to link raw and in-process materials with units of time and production resources in order to create a continuous flow in the factory. The objective is to link factory processes together in a flow and drive it to customer demand instead of to an internal forecast that is inherently inaccurate.\nEarly adopters of DFT included American Standard Companies General Electric and John Deere (Deere & Company).\nIn the early years, DFT was regarded as a method for \"just-in-time\" (JIT), which advocated manufacturing processes driven to actual customer demand via Kanban. It was introduced as a way for American manufacturers to adopt Japanese production techniques, such as Toyota Production System (TPS), whilst avoiding some of the cultural conflicts in applying Japanese business methods in an American company. Later, it has come to be seen as a lean manufacturing method that allows factories to implement techniques such as one-piece flow, TAKT-based line design, Kanban material management and demand-driven production.\nDemand Flow Technology is promoted as a method for any product, any day, any volume. In 2001, Costanza was awarded a patent for this approach for mixed-model manufacturing.\nPrinciples.\nDemand-driven manufacturing.\nThe central tenet to DFT is the primacy of customer demand in daily execution of the operation. According to Aberdeen Group,\nDFT is a pathway to achieve demand-driven manufacturing capability. It is used as a framework to guide the design, implementation and deployment of demand driven manufacturing in a repeatable form. In this way, it is similar original concept of Just-in-Time (JIT) that was first deployed in Japanese manufacturers using a foundation of total quality management. More recently, Just-in-time has been more commonly used to describe supplier delivery methods, rather than a production philosophy. DFT assumes basic process capability that can arise from TQM and statistical process control (SPC) principles and embeds it in a framework of management that can more easily achieve demand driven in a repeatable way.\nAs a result, In-Progress and Finished inventories are all but eliminated, converted permanently into cash at full market value through much faster response to customer orders.\nCash released from Working Capital in this way no longer has to be reinvested in inventory. It becomes available to retire debt, fund growth and innovation.\nMixed-model production.\nMixed-model production is the production of a wide range of product models using a certain degree of shared resources and common material. It is commonly accepted that modern manufacturing places a greater pressure on producers for more choice in the product offering. Products are increasingly assembled from standard components and sub-assemblies, using machines and automated systems as well as manual labour. DFT is designed to handle this mix and provide a way to establish mixed-model production lines.\nA production schedule based on MRP will tend to cope with high product mix by allocating each model to a multiple of a shift or a day. This means that the whole product mix is supplied across a scheduling cycle of a multiple of weeks. This tends to extend the lead-time or increase dependency on the forecast. DFT offers “The ability to accommodate a range of volumes for any product, any day, based on the direction of actual customer demand”.\nProduct synchronization.\nThe first tool to be used in a DFT implementation, product synchronization is a definition of relationship of processes in a flow to build a product. It takes the form of a diagram, usually created in pen and paper or whiteboard and formalized with a visualization program such as Microsoft PowerPoint or Visio. It displays how the processes relate to each other in a flow, with the conversion of raw material to finished goods. A process is defined by \"A logical grouping of value-adding work performed to a common volume\".\nSequence of events (SoE).\nEach of the processes in the product synchronization requires a standard process definition. In DFT, the sequence of events provides this definition. In \"The Quantum Leap\", written by Costanza, the sequence of events is defined as \"[t]he definition of the required work and quality criteria to build a product in a specific production process.\"\nThe SoE usually takes the form of a table with the product code, process ID, task description and sequence, required work and set-up time for machines and labour, and quality check criteria. The SoE intends to define times that are reasonable, realistic and repeatable to perform to the necessary quality. Many of the strengths and criticisms of DFT as a methodology stem from the SoE. The SoEs are the foundation of process definition but are not used as work instructions. To communicate standard work at the work center, operation method sheets are used.\nIn an MRP systems environment, the SoE represents a drill-down from the routing that provides a tabular view of the Product Synchronization at the process level. A DFT manufacturer would therefore use the SoE as the master record of process definition and derive routings and ISO documentation from it.\nOperation method sheets.\nThese are visual description of work in motion, materials and the required quality check. In the purest form, operation method sheets are drawn in wire-frame to show the significant contours of the product form and clearly represent work in motion and quality without visual noise. The OMS has three stages of activity: total quality check, work, and verify. This establishes the concept where each operator checks the output quality of the operation immediately upstream. This can contribute to a total quality culture and parts-per-million capability.\nMixed-model process map.\nThe sequence of events and product synchronization define how tasks and quality check compose the process for any given product. The mixed-model process map shows how products and processes form a requirement for resources. In such a map, the products and processes form a matrix with products as rows and processes as columns. At the intersection are most commonly actual times (standard times at the process from the sequence of events), but could also display yield and optionality ratios.\nDemand at capacity.\nDemand at capacity is the volume of production for a single product item at capacity. It is a fixed value that defines the maximum daily rate of supply. The Demand-at-Capacity is often confused with the daily rate of production. In contrast to Toyota Production System, and many other lean manufacturing derivatives, a DFT line is designed for variable output rates according to daily demand. Thus, the demand data that are used for line design represent a limit quantity not an actual rate of supply. The relationship between the Dc and the average daily demand will be driven by the required service level of the product item to market demand. A higher service level will call for capacity that can supply a higher daily rate than the average over a long range. This will likely affect the resource productivity and inventory levels. A greater mix on the line is able to provide a higher level of service for any given level of resources and inventory.\nEffective hours.\nThe effective hours is the time available for a given resource to produce product or perform process set-up or changeover. It is defined per shift and represents the total available time to perform tasks set in the SoE. Non-productive time such as equipment maintenance, breaks, 5S activity and continuous improvement is deducted from effective hours. Setup time is included as it is arguably a form of productive time and calculations for batch size optimization and dynamic Kanban will require setup and run-time to be managed from a common pool of resource time.\nTakt & Operational Cycle-Time, OP c/t.\nTakt-time is the ratio of time to volume at capacity and in DFT is expressed as\nWhere HE is Effective Hours, S is the number of shifts and DC is the demand at capacity, a daily rate set for design purposes at some point 2 to 5 years into the future. This ratio can be expressed for finished products at the end of the line and is referred to as Takt-Time. It can also apply at the process where bill of material relationships, process yield and optionality can affect the dependent volume for any given Dc at the finished goods level. At the process level, this ratio is known as operational cycle-time.\nTakt time is typically used to calculate the \"line design\" or number and disposition of physical resources required to produce a given mix and volume of products that changes on a daily basis according to customer demand.\nUniquely to DFT Takt time is constant, based on a fixed mix and product volume which is set for factory design purposes 2 to 5 years into the future. This allows for a stable \"line design\" that does not need to change on a daily basis. Daily changes in mix and volume are accommodated in DFT by adjusting the number of people working in production. Those not required to meet the Daily Rate (Dr) are free to spend quality time in training and continuous improvement activities.\nWeekly scheduling cycles to achieve level-loading of mix and volume, which cause significant planning delays, are eliminated. It becomes possible to produce any product on any day in response to real customer demand making possible a true Demand Flow.\nAs a result, In-Progress and Finished inventories are all but eliminated, converted permanently into cash at full market value through much faster response to customer orders.\nCash released from Working Capital in this way no longer has to be reinvested in inventory. It becomes available to retire debt, fund growth and innovation etc.\nMaterial Kanban.\nDFT shares a conventional definition of material Kanban based on a visual signal to replenish a point of consumption with required material. A typical material Kanban system in DFT is \"Single Card, Multiple Container\" and enables card or container quantities to be consumed and replenished without shortages.\nMaterial Kanban provides an alternative to kitting as a way of issuing material to the production floor. A DFT environment will strive to simplify the definition of warehouse locations for material and reduce the number of transactions required to control the flow of material during production. The aim of Material Kanban is to connect the material flow with actual requirement at the process and provide a more robust availability of parts to production whilst reducing the response-time to the customer.\nProduction Kanban.\nProduction Kanban is designed for a replenishment quantity that may be smaller than a lot size or batch. It is based on a \"dual card Kanban\" system where a \"move\" card or container represents the quantity required by the downstream point of consumption and a \"produce\" card is kept on a display board and accumulates to a replenishment batch.\nDemand-based management.\nDemand-based management is an approach that defines tolerance capability for demand in order to unify material and production planning under conditions of demand uncertainty. It uses \"flex fences\" to set the upper and lower boundaries of supply against a definition of the current daily rate of demand. The current rate is usually some kind of smoothed average and will move over time. The flex-fences will be different for different product items or groups and should be calculated individually. Order policies, purchasing, inventory and production capacity will all be set against these flex fence boundaries, so these calculations will sit at the heart of operations planning.\nUnfortunately, this is a calculation-intensive and critical process that is largely unsupported by MRP/ERP systems. The lack of system tools and clash with conventional MRP planning routine are primary reason why demand-based management has not had the same level of adoption experienced by the rest of the DFT principles.\nValue and results.\nCompanies that implement DFT are typically looking for an improvement in the response to customer demand. This is reflected in the lead-time or replenishment time for finished product and will affect the level of inventory that is held to buffer response requirements.\nEffective response to demand can be described as a distribution curve, with some orders taking longer to fill than others. The result is variation and uncertainty in the manufacturer’s ability to serve the market. Working capital is required to hedge this response lag and uncertainty.\nDFT aims to reduce both the variation and duration of response to demand. This can be seen as a more capable fulfillment that provides a higher level of customer service at a lower level of working capital. The intended results are improvement in delivery performance together with increased cash-flow and return on working capital.\nApplications.\nDemand flow technology is applicable in a wide range of product environments and has been successfully deployed in many different industries. Companies who have embraced demand flow technology include John Deere, Flextronics, American Standard Companies, Trane, AstraZeneca and many others. It has a strength in those manufacturing operations that are expected to supply a high mix to an unpredictable and volatile market. It is often seen as the science behind flow manufacturing for discrete manufacturers, whose products do not naturally flow across the manufacturing processes.\nAdvantages and criticisms.\nAdvantages.\nIt is simple.\nDemand flow technology provides a simple, logical method based on applied mathematics. The technique is based on simple operators of addition, subtraction, multiplication and division so it does not rely on advanced mathematics.\nIt is repeatable.\nDFT forms a step-by-step guide to converting production from a scheduled-push to a demand-pull and flow system. Although it is applicable to a wide range of products, the steps are consistent and work in the same way. It does not depend on the judgment of an expert in the same way as lean or Six Sigma and can be taught to a broader audience through short training workshops.\nIt is effective.\nAt its heart, DFT formalizes the natural flow of material, processes and information required to build a product. It is not so much an invented technology as a description of the optimal way to align a factory towards customer demand.\nIt is customer-centric.\nDFT places the customer at the center of the operation. It enables companies to formalise a customer-centric view with practical tasks and actions that guide behaviour in the organisation. It moves the concept of customer-driven to an achievable plan of action beyond a statement of philosophy.\nIt aligns business and customer goals.\nThe concept of maximizing shareholder value is often seen as a conflict with the quality of customer service. Demand Flow Technology, if applied correctly, can unify financial and customer objectives in a holistic approach to managing operating capital and growing a business.\nCriticisms.\nIt is constrained to the factory.\nDemand flow techniques have been widely applied to the factory, yet have failed to gain widespread acceptance in corporate management. All too often, it tends to be limited to production planning whilst operations and material planning continue to be dominated by use of ERP/MRP systems. The holistic ideal of demand flow may be fractured by this conflict.\nIt is unsupported by systems.\nMajor ERP/MRP vendors have largely ignored the advantages of Demand Flow techniques, or been acquired before their products have had a chance to gain market share. The advocates and users of Demand Flow have largely failed to challenge the inadequate logic that conventional MRP uses for planning capacity and production resources As a result, manufacturers are forced to rely on an outdated routine for planning that is largely unchanged since the 1960s.\nIt requires process definition and discipline.\nDFT aims to apply a standard process definition of product to daily requirements of demand. This favours processes that are capable and defined to the task level. This is sometimes a level of detail and discipline absent from the organisation. The creation and maintenance of Sequence of Events documentation involves extensive manual work. There are powerful advantages to quality and capability in performing this work, but success usually depends on management commitment to change beyond the narrow actions of a DFT implementation.", "Engineering,_Manufacturing": 0.9997990727, "qwen": "Yes"}
{"id": "20605304", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=20605304", "title": "Free machining steel", "text": "Free machining steel is steel that forms small chips when machined. This increases the machinability of the material by breaking the chips into small pieces, thus avoiding entanglement in the machinery. This enables automatic equipment to run without human interaction. Free machining steel with lead also allow for higher machining rates. Free machining steel costs 15 to 20% more than standard steel, but this higher cost is offset by increased machining speeds, larger cuts, and longer tool life.\nThe disadvantages of free machining steel are: ductility is decreased; impact resistance is reduced; copper-based brazed joints suffer from embrittlement with bismuth free machining grades; shrink fits are not as strong.\nTypes.\nThere are four main types of free machining steel: \"leaded\", \"resulfurized\", \"rephosphorized\" and \"super\". Super free-machining steels are alloyed with tellurium, selenium, and bismuth.\nMechanics.\nFree machining steels are carbon steels that have sulfur, lead, bismuth, selenium, tellurium, or phosphorus added. Sulfur forms the compound manganese sulfide, which is soft and acts as a chip-breaking discontinuity. It also acts as a dry lubricant to prevent a built up edge on the cutting tool. Lead works in a similar way to sulfur. Bismuth achieves a free machining steel by melting into a thin film of liquid for a fraction of a microsecond to lubricate the cut. Other advantages to bismuth include: more uniformly distributed because of its similar density to iron; more environmentally friendly, as compared to lead; still weldable.", "Engineering,_Manufacturing": 0.9999806881, "qwen": "Yes"}
{"id": "3856722", "revid": "45497007", "url": "https://en.wikipedia.org/wiki?curid=3856722", "title": "Burr (edge)", "text": "A burr is a raised edge or small piece of material that remains attached to a workpiece after a modification process.\nIt is usually an unwanted piece of material and is removed with a deburring tool in a process called 'deburring'. Burrs are most commonly created by machining operations, such as grinding, drilling, milling, engraving or turning. It may be present in the form of a fine wire on the edge of a freshly sharpened tool or as a raised portion of a surface; this type of burr is commonly formed when a hammer strikes a surface. Deburring accounts for a significant portion of manufacturing costs.\nIn the printmaking technique of drypoint, burr, which gives a rich fuzzy quality to the engraved line, is highly desirable—the great problem with the drypoint medium is that the burr rapidly diminishes after as few as ten impressions are printed.\nTypes.\nThere are three types of burrs that can be formed from machining operations: \"Poisson burr\", \"rollover burr\", and \"breakout burr\". The rollover burr is the most common. Burrs may be classified by the physical manner of formation. Plastic deformation of material includes lateral flow (Poisson burr), bending (rollover burr), and tearing of material from the workpiece (tear burr). Solidification or redeposition of material results in a recast bead. Incomplete cutoff of material causes a cutoff projection.\nBurrs can be minimized or prevented by considering materials, function, shape, and processing in the design and manufacturing engineering phases of product development.\nBurrs in drilled holes cause fastener and material problems. Burrs cause more stress to be concentrated at the edges of holes, decreasing resistance to fracture and shortening fatigue life. They interfere with the seating of fasteners, causing damage to fastener or the assembly itself. Cracks caused by stress and strain can result in material failure. Burrs in holes also increase the risk of corrosion, which may be due to variations in the thickness of coatings on a rougher surface. Sharp corners tend to concentrate electrical charge, increasing the risk of static discharge. Burrs in moving parts increase unwanted friction and heat. Rough surfaces also result in problems with lubrication, as wear is increased at the interfaces of parts. This makes it necessary to replace them more frequently. Electrical charge buildup can cause corrosion.\nDeburring.\nThere are many deburring processes, but the most common are mass-finishing, spindle finishing, media blasting, sanding, grinding, wire brushing, abrasive flow machining, electrochemical deburring, electropolishing, thermal energy method, machining, water jet deburring, and manual deburring.\nManual.\n\"Manual deburring\" is the most common deburring process because it is the most flexible process. It also only requires low cost tools and allows for instant inspection.\nManual deburring is either done with tools like scrapers, files, sandpaper, stones and reamers or with handheld power tools that use abrasive points, sandpaper, or cutters similar to those used to deburr during machining.\nElectrochemical.\n\"Electrochemical deburring\" is the use of electrochemical machining to deburr precision work pieces and edges that are hard-to-reach, such as intersecting holes. The process uses a salt or glycol solution and electricity to dissolve the burr. The electric current is applied with a specialized tool to reach the burr location. Burrs are removed in 5 to 10 seconds, while the rest of the work piece is unaffected.\nThermal.\n\"Thermal energy method\" (TEM), also known as \"thermal deburring\", is a deburring process used to remove hard-to-reach burrs or burrs from multiple surfaces at the same time. The process uses an explosive gas mixture to provide thermal energy to burn off the burrs. It is the fastest burr removal process, requiring only 20 milliseconds to remove a burr.\nThe process starts by loading the workpiece into an explosion-proof chamber, which is then sealed and clamped with approximately . The chamber is then evacuated of air and filled with an oxygen and fuel mix; this mixture is pressurized to . An electrical igniter then ignites the mixture, which burns for approximately 20 milliseconds, causing all of the sharp corners and burrs to burn away. The peak temperature reaches .\nCryogenic.\n\"Cryogenic deburring\" is a cryogenic process used to remove burrs and flash from plastic and die cast workpieces. The process works by tumbling and/or abrasively blasting the workpieces at cryogenic temperature levels. The low temperatures (approximately ) are achieved using liquid nitrogen, liquid carbon dioxide, or dry ice. This low temperature brings the material below its embrittlement temperature, which causes the flash or burrs to be easily removed via tumbling or media blasting. This process has been around since the 1960s to deflash plastic and rubber. Common materials that are typically cryogenically deburred with blast media include PEEK, nylon, Teflon, Delrin, polypropylene, polycarbonate, acetal, PTFE, PET, HDPE, PVC, ABS and many others.\nMechanical.\n\"Mechanical deburring\" is a deburring process that either mechanically grinds a burr off of metal or rolls the edge of the dangerous slit or sheared metal burrs into itself. Rolled mechanical deburring was first developed in the 1960s by Walter W. Gauer from Gauer Metal Product, Inc. as a means to speed up the process of hand deburring strips of metal that were used in bakery racks.\nWater jet.\nOne of the main benefits of \"waterjet deburring\" is a high level of precision and repeatability - and for this reason, CNC control is used. This eco-friendly process uses high-pressure water to remove loose burrs and chips even in deep holes – all while leaving the parts cleaner and free of debris. Pressurized water is precisely focused via CNC control to remove burrs and chips in and around parts. Depending on the cleanliness specifications, this can be performed submerged or in an open-air environment. Open-air washing/deburring targets specific areas of the part where the water jet is focused. Submerged will clean the entire part, internally and externally. \nUltrasonic Deburring.\nPowerful ultrasonic waves are irradiated against the tank containing the liquid.\nThis technology removes burrs by the pressure generated within the liquid as cavities are generated and dissipated.", "Engineering,_Manufacturing": 0.9999827147, "qwen": "Yes"}
{"id": "7339924", "revid": "1086799063", "url": "https://en.wikipedia.org/wiki?curid=7339924", "title": "Copper pour", "text": "In electronics, the term copper pour refers to an area on a printed circuit board filled with copper (the metal used to make connections in printed circuit boards). Copper pour is commonly used to create a ground plane. Another reason for using copper pour is to reduce the amount of etching fluid used during manufacturing.\nA distinctive feature of copper pour is the \"backoff\" (or \"stand-off\") - a certain distance between the copper pour and any tracks or pads not belonging to the same electrical net. A copper pour therefore looks like it flows around other components, with the exception of pads which are connected to the copper pour using thermal connections.\nPCB designers today almost invariably use completely solid areas of copper pour that completely cover the remaining area outside those tracks, pads, and stand-off regions. Many early PCBs have a \"hatched copper pour\", sometimes called a \"cherry pie lattice\".\nWhile solid copper pour provides better resistive characteristics, hatched copper pour is used to balance the heat and dilatation on both sides of the board in order to avoid warping of certain substrate.\nHeating might cause gas bubbles between solid copper pour and certain substrates. Furthermore, it might be possible to adjust the impedance of high frequency traces by using hatched copper pour in order to reach better signal quality.", "Engineering,_Manufacturing": 0.9995874763, "qwen": "Yes"}
{"id": "7361378", "revid": "15242876", "url": "https://en.wikipedia.org/wiki?curid=7361378", "title": "Retrogression heat treatment", "text": "Retrogression heat treatment (RHT) is a heat treatment process that rapidly heat treats age-hardenable aluminum alloys. Mainly induction heating is used for RHT. In the past, it was mainly used for 6061 and 6063 aluminum alloys. Therefore, forming of complex shapes is possible, without creating damages like cracks. Even hard tempers (for example -T6) can be formed easily after subjecting these alloys to RHT.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "40519576", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=40519576", "title": "ViTrox", "text": "ViTrox Corporation Berhad  is a Malaysian based electronics company located at Penang, Malaysia. ViTrox specializes in designing and developing automated vision inspection system and equipment testers for the semiconductor and electronic packaging industries as well as electronic communications equipment.\nThe name ViTrox reflects the core business of the company, which is machine vision and electronics. \nViTrox's core products are its Machine Vision System (MVS), Automated Board Inspection (ABI) and Electronics Communication System (ECS).\nHistory.\nViTrox Technologies was established in 2000 in Penang by Chu Jenn Weng and Steven Siaw Kok Tong who studied together at University Sains Malaysia in the 1990s inside their bedroom garage. Chu had an inspiration of becoming an entrepreneur after visiting Hewlett Packard garage in USA. Therefore, after he had worked in a multinational corporation (MNC) for several years, he roped in Siaw as a business partner to handle the operations and marketing parts of business while Chu focus on the technical sides of the operations. As their business expanded, the business operations was moved from their bedroom garage to the Krystal Point, Bayan Baru. As the business continued to grow, business operations moved to several places.\nIn 2006, ViTrox secure exclusive contracts with SRM, another Penang based MNC specializing in electric test handler for 10 years estimated to be worth of RM100 million. \nDuring the financial crisis of 2007–2008, ViTrox Technologies purchased AXI and AOI business unit from Agilent as the former company decides to exit the business to focus on the electronic test.\nWith the purchase of AXI and AOI from Agilent, ViTrox Technologies now have 4 different segments of business units which are system integrator and provider of high-speed machine vision inspection systems, automated optical inspection, X-Ray inspection and electronics communication systems to cater different kind of vision test for different segments of customer bases in semiconductor related industries worldwide. ViTrox key customers are in the back-end semi-conductor assembly and packaging industry as well as the electronics manufacturing and contract manufacturing industry.\nIn 2013, ViTrox have an internal target of \"555 strategy\" which meant have the annual turnover of MYR500 million, have 500 employees by the end of 2015. But as the year 2015 is reaching near with the target is nowhere near the sights, Chu switched its plans to \"Asia Expansion Strategy\" whereby they are focusing in Asia regions naming China, Taiwan, Japan, Korea, Indonesia and the Philippines.\nBusiness unit.\nViTrox core products are divided into 4 categories:\n(i) machine vision system (MVS) is used in the back-testing of semiconductor components, utilizing cameras and sensors to automatically detect dimensional/visual defects and surface markings by capturing images from different angles for computer analysis, performing various inspections such as mark and orientation assessment, pad and package inspection, lead/ball co-planarity examination, and mark/lead inspection within the tape. \n(ii) automated optical inspection (AOI) identify defects that arise during the production of printed circuit boards (PCB), flexible printed circuit boards (FPC), and high density interconnect (HDI) substrates.\n(iii) automated X-ray inspection (AXI) system, utilizes X-rays instead of optical cameras to provide a non-invasive inspection solution, enabling it to inspect hidden solder joints, component shields, and high-density server boards.\n(iv) electronic communication system (ECS) utilizes X-rays instead of optical cameras to provide a non-invasive inspection solution, enabling it to inspect hidden solder joints, component shields, and high-density server boards.\nOffice Locations.\nCurrently, there are total of 8 offices branches across the globe.", "Engineering,_Manufacturing": 0.9989631176, "qwen": "Yes"}
{"id": "36133329", "revid": "7611264", "url": "https://en.wikipedia.org/wiki?curid=36133329", "title": "Poly diamond powder", "text": "Poly diamond powder is a kind of synthetic diamond which is synthesized through explosion method. Compared to mono diamond, poly diamond powder has more crystal edges and grinding surface, every crystal edges have grinding force. During the polishing process, the big grit can fall into small pieces so it can keep the sustaining grinding force without scratches.\nProduction method.\nDetonation——Purification——Shaping——Grading——Finished Product\nApplication.\nPoly diamond powder mainly is used in sapphire substrate, diaphragm, and LED chips etc.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "30920317", "revid": "28180078", "url": "https://en.wikipedia.org/wiki?curid=30920317", "title": "Arc blow", "text": "Arc blow is the, usually unwanted, deflection of the arc during arc welding.\nThere are two types of arc blow commonly known in the electric welding industry: \"magnetic\" and \"thermal\".\nMagnetic arc blow.\nMagnetic arc blow or \"arc wander\" is the deflection of welding filler material within an electric arc deposit by a buildup of magnetic force surrounding the weld pool. Magnetic arc blow can occur because of: \nArc blow tends to occur if the material being welded has residual magnetism at a certain level, particularly when the weld root is being made, and the welding current is direct current (DC positive or negative).\nMagnetic arc blow is popularly attributed to a change in the direction of current as it flows into and through the workpiece. Magnetic arc blow is known to begin at field densities as low as 10 gauss and becomes severe at densities of, equal to or greater than, 40 gauss; it is directional and can be classified as \"forward\" or \"backward\" moving along the joint, but can occasionally occur to the sides depending on the orientation of the poles to the workpiece.\nMagnetic arc blow is more common in DC welding than in AC welding.\nThermal arc blow.\nThermal arc blow is widely attributed to variations in resistance within the base metal created by the weld pool as it is moved across the workpiece. Thermal arc blow can occur because of:\nThermal arc blow is not as severe as magnetic arc blow, but can still leave undesirable defects in the weld deposit.", "Engineering,_Manufacturing": 0.9999555349, "qwen": "Yes"}
{"id": "30922704", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=30922704", "title": "Firecracker welding", "text": "Firecracker welding is a rarely used form of shielded metal arc welding (SMAW).\nA flux-coated electrode, as used for SMAW (manual stick welding), is laid horizontally above a close-fitting butt weld. An arc is struck at one end of the electrode, which then burns along the length of the electrode. The electrode is held in place by either copper blocks, clamps or adhesive tape.\nProcess.\nManual metal arc welding is relatively slow, as much time is spent stopping to fit new electrodes and to clean slag before restarting. Firecracker welding allows a weld the entire length of an electrode to be welded in one pass, without pausing. Extra-long electrodes may be used to increase the length that may be welded in one pass, up to 72 inches (1.8 meters).\nThe need to clean slag from a manual weld before restarting increases the risk of accidental slag inclusion in the finished weld. This risk is avoided through the use of firecracker welding. As the electrode position is also constant relative to the weld, the risk of porosity is also reduced, to the level of a skilled welder. The process is also suitable for use in areas with limited access. Once started it continues automatically, without needing enough space for a skilled welder with sight of the weld.\nOne drawback is that the size of the bead deposited is limited by the cross-section of the electrode, as there is no scope for manually weaving the arc to deposit more rod in less weld length. For this reason, the flux coating often contains iron powder, to give additional deposition. The rod coating is generally the same as for manual arc, with no change being required. Experiments have been conducted where the coating was thinned on the side in contact with the workpiece, although this does not seem to show a great advantage.\nHistory of application.\nThe process was developed in Austria in 1938 by Georg Hafergut. The process was known as \"Elin-Hafergut\" welding.\nThe process, with its suitability for long welds in flat sheet was recognised as being useful for shipbuilding and bridgebuilding and has been studied specifically for these applications.", "Engineering,_Manufacturing": 0.9995346069, "qwen": "Yes"}
{"id": "30928312", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=30928312", "title": "Weld pool", "text": "In metalworking, weld pool commonly refers to the dime-sized workable portion of a weld where the base metal has reached its melting point and is ready to be infused with filler material. The weld pool is central to the success of the welding process. It was first observed in oxy-fuel welding by Fouché & Picard in 1903, after the discovery of acetylene by Edmund Davy in 1836. \nThe weld pool must be carried along the joint in a consistent width and depth, and the motion used to carry the weld pool has a direct effect on the quality of the weld bead. A weld made by starting and carrying a weld pool, without the addition of a filler material, is called an autogenous weld.", "Engineering,_Manufacturing": 0.9999779463, "qwen": "Yes"}
{"id": "30935748", "revid": "7852030", "url": "https://en.wikipedia.org/wiki?curid=30935748", "title": "Profitability analysis", "text": "In cost accounting, profitability analysis is an analysis of the profitability of an organisation's output. Output of an organisation can be grouped into products, customers, locations, channels and/or transactions. \nDescription.\nIn order to perform a profitability analysis, all costs of an organisation have to be allocated to output units by using intermediate allocation steps and drivers. This process is called costing. When the costs have been allocated, they can be deducted from the revenues per output unit. The remainder shows the unit margin of a product, client, location, channel or transaction.\nAfter calculating the profit per unit, managers or decision makers can use the outcome to substantiate management decisions. Managers can decide to stop selling loss making products, to reduce costs for loss making customers or to increase sales in profitable locations.\nPareto analysis.\nIn profitability analysis it is possible to perform a Pareto analysis by ranking output units from most profitable to least profitable. By doing so it is possible to create a so-called 'Whale Curve', graphically showing the potential margin of an organisation.", "Engineering,_Manufacturing": 0.9999939203, "qwen": "Yes"}
{"id": "38627568", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=38627568", "title": "Scissel", "text": "Scissel is the scrap produced in the punching of coin blanks from a continuous strip of metal. The scrap is collected and remelted to form new sheets, or may be melted for manufacture of other alloys.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "38652959", "revid": "46314390", "url": "https://en.wikipedia.org/wiki?curid=38652959", "title": "Ingersoll Machine Tools", "text": "Ingersoll Machine Tools is a manufacturer located in Rockford, Illinois that produces large scale machine tools for use in metal cutting, 3D Printing, and automated fiber placement.\nHistory.\nThe company was founded in 1891 by Winthrop Ingersoll when he moved W.R. Eynon & Co. from Cleveland, Ohio to Rockford. Originally, Ingersoll Machine Tools focused almost entirely on milling machinery and processes for metal removal. It acquired contracts from General Electric and, by 1917, was closely involved with wartime production and had a workforce of 600. \nIngersoll went on to produce customized machines for industries such as airplane and auto manufacturing. In the period from the 1960s to the 1980s, the company employed around 2,000 people at its plant, also developing CNC technologies to introduce automation into its manufacturing processes.\nBankruptcy.\nIn 2003, Ingersoll International went bankrupt. The company was purchased by the Italian Camozzi Group. Since its purchase by Camozzi, the company has attempted to redefine its place in the market, continuing with milling machines but also expanding into other areas.\nPresent activities.\nIngersoll Machine Tools is a supplier of machine tools, including large five axis milling machines, large 3D Printers, and automated fiber placement (AFP) for the aerospace industry. It has made the wing molds for Mitsubishi, supplier of the wings on the Boeing 787. In 2010, it received Best Supplier Award from Alenia Aeronautica.\nIngersoll's AFP machines are also installed at UTC Aerospace Systems' (formerly Goodrich Corporation) facilities in Riverside, California. At this facility, the machines are used to layup the engine nacelles for the Boeing 787 and Airbus A350.\nIngersoll has also continued working in the metal cutting industry, with much of its contract production being for the Defense, Aerospace, and wind industry. It has also sold machinery to NASA.\nIn 2019, the Guinness Book of Worlds Records certified that Ingersoll has produced the World's Largest 3D Printer. The product, named MasterPrint, was installed at the University of Maine. \nIn addition to building machine tools, Ingersoll has built and installed large telescopes for Astronomy research. Most recently, they were selected to build the mount for the Giant Magellan Telescope, which will be installed in Chile.\nIngersoll Machine Tools was awarded the 2020 Manufacturer of the Year by the Rockford, Illinois Chamber of Commerce.\nExternal links.\n ", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "683683", "revid": "9784415", "url": "https://en.wikipedia.org/wiki?curid=683683", "title": "Net investment", "text": "In economics, net investment is spending which increases the availability of fixed capital goods or means of production and goods inventories. It is the total spending on newly produced physical capital (fixed investment) and on inventories (inventory investment)—that is, gross investment—minus replacement investment, which simply replaces depreciated capital goods. It is productive capital formation plus net additions to the stock of housing and the stock of inventories.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "2755575", "revid": "2810812", "url": "https://en.wikipedia.org/wiki?curid=2755575", "title": "Rack unit", "text": "A rack unit (abbreviated U or RU) is a unit of measure defined as . It is most frequently used as a measurement of the overall height of 19-inch and 23-inch rack frames, as well as the height of equipment that mounts in these frames, whereby the height of the frame or equipment is expressed as multiples of rack units. For example, a typical full-size rack cage is 42U high, while equipment is typically 1U, 2U, 3U, or 4U high.\nDefinition.\nThe rack unit size is based on a standard rack specification as defined in EIA-310. The Eurocard specifies a standard rack unit as the unit of height; it also defines a similar unit, horizontal pitch (HP), used to measure the width of rack-mounted equipment. The standard was adopted worldwide as \"IEC 60297 Mechanical structures for electronic equipment – Dimensions of mechanical structures of the series\", and defines the sizes for rack, subrack (a shelf-like chassis in which cards can be inserted), and the pitch of printed circuit boards/cards providing physical compatibility of technological equipment, typically in telecommunications.\nWhile a rack unit is defined as , a front panel or filler panel in a rack is not an exact multiple of this height. To allow space between adjacent rack-mounted components, a panel is inch  less in height than the full number of rack units would imply. Thus, a 1U front panel would be 1 inch  tall. If \"n\" is number of rack units, the ideal formula for panel height is for calculating in inches, and for calculating in millimetres. Manufacturing allows for dimensions with less precision.\nThe mounting-hole distance (as shown to the right) differs for 19-inch racks and 23-inch racks: The 19-inch racks uses uneven spacings (as shown to the right) while the 23-inch racks uses evenly spaced mounting holes. Although it is called a 19-inch rack unit, the actual mounting dimensions of a 19-inch rack unit are 18 inches  wide, center to center.\nThe 19-inch rack format with rack-units of was established as a standard by AT&T around 1922 in order to reduce the space required for repeater and termination equipment in a telephone company central office.\nConfigurations.\nA typical full size rack is 42U, which means it holds just over of equipment, and a typical \"half-height\" rack is 18–22U, which is around high.\nWhereas there is no formal specification for \"half rack\", the term \"half-rack\" can have different separate meanings: It can describe equipment that fits in a certain number of rack units, but occupy only \"half the width\" of a 19-inch rack . These are commonly used when a piece of equipment does not require full rack width, but may require more than 1U of height. For example, a \"4U half-rack\" DVCAM deck occupies 4U (7 in) height × 9.5 in width, and in theory, two 4U half-rack decks could be mounted side by side and occupy the 4U space. It can also describe a unit that is 1U high and \"half the depth\" of a 4-post rack (such as a network switch, router, KVM switch, or server), such that two units can be mounted in 1U of space (one mounted at the front of the rack and one at the rear). When used to describe the rack enclosure itself, the term \"half-rack\" typically means a rack enclosure that is \"half the height\" (22U tall). There is also a \"half rack width\" size being used in IT applications where a device conforms to a smaller than 9.5\" width so that these \"half rack width\" appliances may be used in a chassis system that fits the traditional 19\" rack space, but allows for these 8.4 inch wide \"half rack width\" appliances to be inserted and removed easily without tools or the need to remove adjacent hardware. This \"half rack width\" concept is popular in applications where IT equipment is being used by military who are unable to use traditional 1U full depth IT appliances due to their large size. \nRack units are universally the same, but the type of thread can vary depending on the rack. Mounting rails can be No. 10-32 tapped (Unified Thread Standard), No. 12-24 tapped, metric M6 threaded or universal square holes. Universal square holes are becoming the most common as these allow the insertion of replaceable cage nuts for the type of thread needed. This prevents stripping of the threading on the rails and allows for more flexibility.", "Engineering,_Manufacturing": 0.9996032119, "qwen": "Yes"}
{"id": "2756918", "revid": "39166520", "url": "https://en.wikipedia.org/wiki?curid=2756918", "title": "Surface finishing", "text": "Surface finishing is a broad range of industrial processes that alter the surface of a manufactured item to achieve a certain property. Finishing processes may be employed to: improve appearance, adhesion or wettability, solderability, corrosion resistance, tarnish resistance, chemical resistance, wear resistance, hardness, modify electrical conductivity, remove burrs and other surface flaws, and control the surface friction. In limited cases some of these techniques can be used to restore original dimensions to salvage or repair an item. An unfinished surface is often called \"mill finish\".\nSurface finishing processes can be categorized by how they affect the workpiece:\nMechanical processes may also be categorized together because of similarities the final surface finish.\nMechanical finishing.\nMechanical finishing processes include:\nThe use of abrasives in metal polishing results in what is considered a \"mechanical finish\".\nMetal finish designations.\nAnnealed and descaled after hot rolling, this finish is suitable for industrial applications requiring heat resistance and corrosion resistance, where smoothness of finish is unimportant, such as chemical tanks, aircraft heaters, steam turbine shrouds and piping.\nAlso known as grinding, roughing or rough grinding. These finishes are coarse in nature and usually are a preliminary finish applied before manufacturing. An example would be grinding gates off of castings, deburring or removing excess weld material. It is coarse in appearance and applied by using 36–100 grit abrasive.\nWhen the finish is specified as #3, the material is polished to a uniform 60–80 grit.\nAlso known as brushed, directional or satin finish. A #4 architectural finish is characterized by fine polishing grit lines that are uniform and directional in appearance. It is produced by polishing the metal with a 120–180 grit belt or wheel finish and then softened with an 80–120 grit greaseless compound or a medium non woven abrasive belt or pad.\nThis finish is commonly used for the medical and food industry and almost exclusively used on stainless steel. This finish is much finer than a #4 architectural finish. This finish enhances the physical appearance of the metal as well as increases the sanitary benefits. One takes great care to remove any surface defects in the metal, like pits, that could allow bacteria to grow. A #4 dairy or sanitary finish is produced by polishing with a 180–240 grit belt or wheel finish softened with 120–240 grit greaseless compound or a fine non woven abrasive belt or pad.\nAlso known as a fine satin finish. This finish is produced by polishing with a 220–280 grit belt or wheel softened with a 220–230 greaseless compound or very fine non woven abrasive belt or pad. Polishing lines will be soft and less reflective than a #4 architectural finish.\nA #7 finish is produced by polishing with a 280–320 belt or wheel and sisal buffing with a cut and color compound. This is a semi-bright finish that will still have some polishing lines but they will be very dull. Carbon steel and iron are commonly polished to a #7 finish before chrome plating. A #7 finish can be made bright by color buffing with coloring compound and a cotton buff. This is commonly applied to keep polishing costs down when a part needs to be shiny but not flawless.\nAlso known as a mirror finish. This finish is produced by polishing with at least a 320 grit belt or wheel finish. Care will be taken in making sure all surface defects are removed. The part is sisal buffed and then color buffed to achieve a mirror finish. The quality of this finish is dependent on the quality of the metal being polished. Some alloys of steel and aluminum cannot be brought to a mirror finish. Castings that have slag or pits will also be difficult, if not impossible, to polish to a #8.", "Engineering,_Manufacturing": 0.9999215603, "qwen": "Yes"}
{"id": "2759248", "revid": "1233313", "url": "https://en.wikipedia.org/wiki?curid=2759248", "title": "Inventory control", "text": "Inventory control or stock control can be broadly defined as \"the activity of checking a shop's stock\". It is the process of ensuring that the right amount of supply is available within a business. However, a more focused definition takes into account the more science-based, methodical practice of not only verifying a business's inventory but also maximising the amount of profit from the least amount of inventory investment without affecting customer satisfaction. Other facets of inventory control include forecasting future demand, supply chain management, production control, financial flexibility, purchasing data, loss prevention and turnover, and customer satisfaction. \nAn extension of inventory control is the inventory control system. This may come in the form of a technological system and its programmed software used for managing various aspects of inventory problems, or it may refer to a methodology (which may include the use of technological barriers) for handling loss prevention in a business. The inventory control system allows for companies to assess their current state concerning assets, account balances, and financial reports.\nInventory control management.\nAn inventory control system is used to keep inventories in a desired state while continuing to adequately supply customers, and its success depends on maintaining clear records on a periodic or perpetual basis. \nInventory management software often plays an important role in the modern inventory control system, providing timely and accurate analytical, optimization, and forecasting techniques for complex inventory management problems. Typical features of this type of software include:\nThrough this functionality, a business may better detail what has sold, how quickly, and at what price, for example. Reports could be used to predict when to stock up on extra products around a holiday or to make decisions about special offers, discontinuing products, and so on. \nInventory control techniques often rely upon barcodes and radio-frequency identification (RFID) tags to provide automatic identification of inventory objects—including but not limited to merchandise, consumables, fixed assets, circulating tools, library books, and capital equipment—which in turn can be processed with inventory management software. A new trend in inventory management is to label inventory and assets with a QR Code, which can then be read with smart-phones to keep track of inventory count and movement. These new systems are especially useful for field service operations, where an employee needs to record inventory transaction or look up inventory stock in the field, away from the computers and hand-held scanners.\nThe control of inventory involves managing the physical quantities as well as the costing of the goods as it flows through the supply chain. In managing the cost prices of the goods throughout the supply chain, several costing methods are employed:\nThe calculation can be done for different periods. If the calculation is done on a monthly basis, then it is referred to the periodic method. In this method, the available stock is calculated by:\nADD Stock at beginning of period\nADD Stock purchased during the period\nAVERAGE total cost by total qty to arrive at the Average Cost of Goods for the period.\nThis Average Cost Price is applied to all movements and adjustments in that period. \nEnding stock in qty is arrived at by Applying all the changes in qty to the Available balance. \nMultiplying the stock balance in qty by the Average cost gives the Stock cost at the end of the period.\nUsing the perpetual method, the calculation is done upon every purchase transaction.\nThus, the calculation is the same based on the periodic calculation whether by period (periodic) or by transaction (perpetual).\nThe only difference is the 'periodicity' or scope of the calculation.\nIn practice, the daily averaging has been used to closely approximate the perpetual method.\n6. Bottle neck method (depends on proper planning support)\nAdvantages and disadvantages.\nInventory control systems have advantages and disadvantages, based on what style of system is being run. A purely periodic (physical) inventory control system takes \"an actual physical count and valuation of all inventory on hand ... at the close of an accounting period,\" whereas a perpetual inventory control system takes an initial count of an entire inventory and then closely monitors any additions and deletions as they occur. Various advantages and disadvantages, in comparison, include:\nVs. inventory management.\nWhile it is sometimes used interchangeably, inventory management and inventory control deal with different aspects of inventory.\nInventory management is a broader term pertaining to the regulation of all inventory aspects, from what is already present in the warehouse to how the inventory arrived and where the product's final destination will be. This management involves tracking field inventory throughout the supply chain, from sourcing to order fulfilment. It encompasses the entire process of procuring, storing, and profiting off merchandise or services.\nInventory control is the process of managing stock once it arrives at a warehouse, store or other storage location. It is solely concerned with regulating what is already present, and involves planning for sales and stock-outs, optimizing inventory for maximum benefit and preventing the pile-up of dead stock.\nBusiness models.\nJust-in-time inventory (JIT), vendor managed inventory (VMI) and customer managed inventory (CMI) are a few of the popular models being employed by organizations looking to have greater stock management control.\nJIT is a model that attempts to replenish inventory for organizations when the inventory is required. The model attempts to avoid excess inventory and its associated costs. As a result, companies receive inventory only when the need for more stock is approaching.\nVMI (vendor managed inventory) and (co-managed inventory) are two business models that adhere to the JIT inventory principles. VMI gives the vendor in a vendor/customer relationship the ability to monitor, plan and control inventory for their customers. Customers relinquish the order making responsibilities in exchange for timely inventory replenishment that increases organizational efficiency.\nCMI allows the customer to order and control their inventory from their vendors/suppliers. Both VMI and CMI benefit the vendor as well as the customer. Vendors see a significant increase in sales due to increased inventory turns and cost savings realized by their customers, while customers realize similar benefits.", "Engineering,_Manufacturing": 0.9967912436, "qwen": "Yes"}
{"id": "447351", "revid": "43558034", "url": "https://en.wikipedia.org/wiki?curid=447351", "title": "Capital good", "text": "The economic concept of a capital good (also called complex product systems (CoPS), and means of production) is as a \"...series of heterogeneous commodities, each having specific technical characteristics ...\" in the form of a durable good that is used in the production of goods or services. Capital goods are a particular form of economic good and are tangible property.\nA society acquires capital goods by saving wealth that can be invested in the means of production. People use them to produce other goods or services within a certain period. Machinery, tools, buildings, computers, or other kinds of equipment that are involved in the production of other things for sale are capital goods. The owners of the capital good can be individuals, households, corporations, or governments. Any material used to produce capital goods is also considered a capital good.\nCapital goods are one of the three types of producer goods, the other two being land and labour. The three are also known collectively as \"primary factors of production\". This classification originated during the classical economics period and has remained the dominant method for classification.\nMany definitions and descriptions of capital goods production have been proposed in the literature. Capital goods are generally considered one-of-a-kind, capital intensive products that consist of many components. They are often used as manufacturing systems or services themselves. Examples include hand tools, machine tools, data centers, oil rigs, semiconductor fabrication plants, and wind turbines. Their production is often organized in projects, with several parties cooperating in networks (Hicks et al. 2000; Hicks and McGovern 2009; Hobday 1998).\nA capital good lifecycle typically consists of tendering, engineering and procurement, manufacturing, commissioning, maintenance, and (sometimes) decommissioning.\nCapital goods are a major factor in the process of technical innovation. \nCapital goods are a constituent element of the stock of capital assets, or fixed capital and play a key role in the economic analysis of \"... growth and production, as well as the distribution of income...\"\nImmaterial capital goods.\nCapital goods can also be immaterial, when they take the form of intellectual property. Many production processes require the intellectual property to (legally) produce their products. Just like material capital goods, they can require substantial investment, and can also be subject to amortization, depreciation, and divestment.\nDifferences from consumer goods.\nPeople buy capital goods to use as static resources to make other goods, whereas consumer goods are purchased to be consumed.\nFor example, an automobile is a consumer good when purchased as a private car.\nDump trucks used in manufacturing or construction are capital goods because companies use them to build things like roads, dams, buildings, and bridges.\nIn the same way, a chocolate bar is a consumer good, but the machines that produce the candy are capital goods.\nSome capital goods can be used in both production of consumer goods or production goods, such as machinery for the production of dump trucks.\nConsumption is the logical result of all economic activity, but the level of future consumption depends on the future capital stock, and this in turn depends on the current level of production in the capital-goods sector. Hence if there is a desire to increase consumption, the output of the capital goods should be maximized.\nImportance.\nCapital goods, often called complex products and systems (CoPS) (Gann and Salter 2000; Hobday 2000), play an important role in today's economy (Acha et al. 2004). Aside from allowing a business to create goods or provide services for consumers, capital goods are important in other ways. In an industry where production equipment and materials are quite expensive, they can be a high barrier to entry for new companies. If a new business cannot afford to purchase the machines it needs to create a product, for example, it may not be able to compete as effectively in the market. Such a company might turn to another business to supply its products, but this can be expensive as well. This means that, in industries where the means of production represent a large amount of a business's start-up costs, the number of companies competing in the market is often relatively small.\nInvestment required.\nThe acquisition of machinery and other expensive equipment often represents a significant investment for a company. When a business is struggling, it often puts off such purchases as long as possible, since it does not make sense to spend money on equipment if the company is not around to use it. Capital spending can be a sign that a manufacturer expects growth or at least a steady demand for its products, a potentially positive economic sign. \nIn most cases, capital goods require a substantial investment on behalf of the producer, and their purchase is usually referred to as a capital expense. These goods are important to businesses because they use these items to make functional goods for customers or to provide consumers with valuable services. As a result, they are sometimes referred to as producers' goods, production goods, or means of production.\nIn international trade.\nIn the theory of international trade, the causes and nature of the trade of capital goods receive little attention. Trade-in capital goods is a crucial part of the dynamic relationship between international trade and development. The production and trade of capital goods, as well as consumer goods, must be introduced to trade models, and the entire analysis integrated with domestic capital accumulation theory.\nSee also.\n§ Listed in \"The New Palgrave Dictionary of Economics\"", "Engineering,_Manufacturing": 0.9999269247, "qwen": "Yes"}
{"id": "32775097", "revid": "548440", "url": "https://en.wikipedia.org/wiki?curid=32775097", "title": "Tailored fiber placement", "text": "Tailored fiber placement (TFP) is a textile manufacturing technique based on the principle of sewing for a continuous placement of fibrous material for composite components. The fibrous material is fixed with an upper and lower stitching thread on a base material. Compared to other textile manufacturing processes fiber material can be placed near net-shape in curvilinear patterns upon a base material in order to create stress adapted composite parts.\nHistory.\nTFP technology was introduced in the early 1990s by the IPF Dresden. At the beginning handmade stitched reinforcement structures (preforms) were manufactured initialized by an industry inquiry about stress adapted fiber-reinforced plastic (FRP) parts with a curvilinear pattern. An adaptation of this method to industrial embroidery machines, by using the sewing capabilities of those automates, was implemented in the mid-90s. The technology was named Tailored Fiber Placement, which describes the variable axial near-net-shape fibre placement capabilities. Nowadays, the Tailored Fiber Placement is already in several companies a well-established textile technology for dry preform manufacturing applying TFP machines by the manufacturer TAJIMA.\nPrinciple of the technology.\nBased on embroidery machinery used in the garment textile industry, the machines have been adapted to deposit and stitch fiber roving material onto a base material. Roving material, mostly common carbon fibers, from about 3,000 up to 50,000 filaments can be applied. The preform is produced continuously by the placement of a single roving. The roving material pulled off a spool is guided by a pipe which is positioned in front of the stitching needle. The roving pipe and the frame, where the base material is fixed onto, move synchronized stepwise to perform a zigzag stitch relative to needle position. The stitching head equipped with roving spool, pipe and needle can rotate arbitrarily 360 degrees. During each stitch the upper thread is pulled through the base material and looped around the lower thread spool. Hence a double backstitch is performed. Currently, up to 800 stitches per minute can be achieved. \nThe base material can be a 2D-textile such as woven or non-woven fabric or a matrix-compatible foil material for thermoplastic composites. The stitching path can be designed in form of a pattern either with the help of classical design embroidery software or more recently by use of 2D-CAD systems. Afterwards necessary information of the stitch positions are added to the pattern with the help of so-called punch software and finally transferred to the TFP machine.\nThe infiltration of TFP-preforms can be done with conventional processing techniques such as resin transfer moulding, vacuum bag molding, pressing and autoclave moulding. In the case of thermoplastic composites the matrix material and the reinforcement fibers can be placed simultaneously e.g. in the form of films or fibers. The base material can then be a thermoplastic foil which melts during the consolidation process and becomes part of the matrix. This type is ideally suited for deep-drawn TFP-preforms.\nAdvantages of the TFP technology.\nOptimizations using TFP over other laminate technologies\nOptimization one: Reduce waste material\nOne of the leading material costs of many traditional carbon fiber composite construction techniques, includes the large amount of waste material generated. In many hand lay-up processes that use carbon fiber woven material, waste materials can easily account for 50% or more of the total weight of carbon used. This waste is generated as the fabric is initially cut before impregnation with the matrix material. Additional waste is generated after the composite has cured during the post processing steps where the shape is further refined. Tailored fiber placement is unique in its ability to reduce waste material and thereby optimize material cost. By controlling the path of the tow material as it is stitched into the desired geometry, material is only placed where it is needed in the final preform. Areas of fabric that would have to be cut out in traditional laminate design are simply left unstitched. This process reduces both the initial waste produced when cutting woven fabrics to shape and reduces post processing waste due to the ability to conform to complex geometries.\nOptimization two: Hybrid carbon fiber and glass fiber composites\nAn additional drawback of traditional laminate processes is the inability to rapidly change materials volumetrically to benefit from their combined advantages. Tailored fiber placement is a method for quickly and effectively creating these multi-material composites. For example, when a structural analysis is performed on a part, it might be discovered that the part only requires areas of localized stiffness. In this case, carbon fiber, with its properties of high stiffness, can be placed exactly at the areas and geometries of the part requiring high stiffness. It would be cost-inefficient to fill the entire part with highly stiff carbon fiber, especially when that stiffness is not required in certain locations. Therefore, to further reduce cost, the areas around the carbon fiber stiffened geometry that do not require high stiffness can be filled in with lower cost materials such as glass fiber or even hemp fibers. Tailored fiber placement allows these material transitions to seamlessly occur.\nOptimization three: Tunable fiber alignment and geometric tailor-ability\nOnce of the largest benefits of using tailored fiber placement to optimize a design, is the ability to precisely control where each tow of carbon fiber is placed in a design. This allows the composites designer to further optimize the materials properties, reducing the need for additional material. For example, complex tow paths of carbon fiber can be embroidered to perfectly resist the applied loads. By aligning fibers to their principal stresses, additional mechanical support is provided without using additional material. Further optimizations can occur by selectively reinforcing holes and circular drill points. In traditional laminate design, these holes can serve as areas of crack propagation due to the orthogonal nature of the woven fabric used. Tailored fiber placement can be used to selectively reinforce around these holes with curvilinear patterns reducing the effective initial crack propagation locations. This can allow for a thinner material at the hole’s location, and even potentially the removal of metal reinforcing washers.\nOptimization four: Tunable localized thickness\nAnother interesting optimization that can occur when using tailored fiber placement in carbon fiber composites utilizes tunable thickness of the process over a given area. In traditional laminate design, carbon fiber composites are presumed to have even thickness. However, tailored fiber placement does not have such a height restriction. In combination with well-designed molding and fixtures, carbon fiber preforms can create localized thickness in highly complicated and varied geometries. In classical beam theory, the moment of inertia for a rectangular beam can be calculated by:\nWhere the height of the material (h) is shown to have cubic influence on the moment of inertia when compared to the base (b) length. This means that localized areas of height can be created with tailored fiber placement that significantly can help to better resist bending at that location. This optimization allows for decreased material usage to achieve the same, if not improved, bulk material properties when compared to other composite processes. ZSK offers machines that can lay fibers up to 8 mm thick. This averages out to about 8 layers of 50 K carbon fiber roving. This thickness can be uniform over the entire surface of the preform part or can be selectively placed in key structural areas for additional material conscience mechanical support.\nOptimization five: Comingled fibrous materials\nOne of the drawbacks of traditional composite laminate manufacturing can be the long cycle times required to properly cure a thermoset resin. New materials, called comingled fibers, have been created to decease the processing time. In comingled fibers, a carbon fiber tow has additional thermoplastic matrix materials added directly into its fiber structure. These comingled materials can be stitched in the same manner as other tailored fiber placement composite materials. However, these preforms can quickly be thermocycled in a heated press to rapidly reduce the cycle processing time. Traditional thermoset composite materials using resin transfer molding can require between 30 minutes to 40 hours to properly set and cure a single piece. Tailored fiber placement of comingled materials allows for the placement of both the reinforcing fiber, and the matrix material in the same preform. As the preform is heated, the liquid matrix is distributed directly into the carbon fiber allowing proper wetting. The tailored fiber placement of comingled fibers eliminates the need for additional resins and can significantly reduce materials cost. Additionally, the desired fiber to volume fraction is created during the comingling step, increasing the uniformity of the composite material from batch to batch. Finally, these comingled fiber composites are a step towards a more sustainable carbon fiber composite due to their ability to be re-melted into new forms at the end of their lifecycle.\nOptimization six: Machine versatility without retooling\nAnother significant process optimization that occurs with tailored fiber placement when compared with other composite processes, is the ability for the production machine to rapidly change its production from one design to a completely different design without any additional retooling of the machine. This can allow the same machine to seamlessly transfer from producing car parts in the morning shift to sporting equipment in the afternoon shift. Additionally, tailored fiber placement can allow the same machine to produce one prototype design at a time to investigate a process and troubleshoot it without wasting excess material, to creating a full production run simultaneously. This rapid prototyping to production capability, in combination with the ability for a machine to run many different types and geometries of parts in rapid succession, allows for more versatile projects to be run on the same machine. This reduces the cost of setting up a new machine each time a new design is generated. In conclusion, the six methods of optimization for carbon fiber composites briefly presented show some of the advantages of tailored fiber placement over traditional composite processes. It is hoped that the combination of these optimization methods, in conjunction with a trend of decreasing carbon fiber material costs, will allow a new class of ubiquitous and highly engineered materials to further improve consumer use cases like fuel efficiency. \nApplications for structural parts.\nThe TFP technology allows the fabrication of preforms tailored for specific composite components or reinforcements. Applications range from highly accelerated lightweight parts for industrial robots or blades for compressors up to CFRP aircraft parts, e.g. I-beam for the NH-90 helicopter, automotive structures and bicycle parts.\nTFP for self-heating tooling and components.\nUsing the carbon roving as an electric heating element offers the possibility to manufacture composite structures with embedded heating layers. Due to the high flexibility in the design of the heating pattern an overall nearly equal heat distribution can be achieved. In terms of applications this technology embedded in solid composite molds is very beneficial for resin consolidation and binder activation in out-of-autoclave processes. Composite molds show similar heat expansion properties as the manufactured composite parts. The lower thermal mass of composite tools compared to common metal molds help to shorten the manufacturing cycle of FRP parts and decrease the energy need for the production process. Further the TFP heating elements can be applied in CFRP wing structures of airplanes or blades of wind mills for anti- and de-icing tasks. The TFP structure embedded in elastomeric heating bags can applied to manufacturing or repairing processes of composite parts.", "Engineering,_Manufacturing": 1.0000091791, "qwen": "Yes"}
{"id": "32784745", "revid": "46307580", "url": "https://en.wikipedia.org/wiki?curid=32784745", "title": "Toyota Trailer T10", "text": "The Toyota Trailer T10 was a trailer manufactured by Toyota that was designed to go behind the Toyota Land Cruiser or the Toyota Weapon Carrier using a ring hitch.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "65092692", "revid": "12827142", "url": "https://en.wikipedia.org/wiki?curid=65092692", "title": "Reticulation (metalwork)", "text": "In metalwork, reticulation refers to a decorative surface finishing technique involving the application of localised heat to the surface of a metal object. Reticulation is typically performed on alloys of silver and copper or of gold and copper.\nReticulation exploits the difference between the melting temperature of an unalloyed metal and that of an alloy of the metal; by depleting the base metal content in the surface layer, a piece can be heated in such a manner so as to render the interior of the piece molten while leaving the surface of the piece intact. The reticulated surface is formed by the thermal expansion and contraction of the interior metal which is effected by deliberate variation in the application of localised heat.\nIn the late 19th century, reticulation was used as a decorative technique by Russian goldsmiths such as Fabergé, where the process was referred to as \"samorodok\" (lit. \"born by itself\"). Use of the technique spread to the Nordic and Scandinavian countries where it was applied in the creation of objects such as cigarette boxes, card cases, eyeglass cases, and flasks.", "Engineering,_Manufacturing": 0.997897923, "qwen": "Yes"}
{"id": "64649692", "revid": "1144167583", "url": "https://en.wikipedia.org/wiki?curid=64649692", "title": "Fill and finish", "text": "In the pharmaceutical industry, fill and finish (also referred to as fill finish, fill-finish or fill/finish) is the process of filling vials with vaccine, biological and pharmaceutical Drug Substances (DS) and finishing the process of packaging the medicine for distribution. Many vaccine manufacturers use third parties to fill and finish their vaccines.\nThe fill/finish process is a common bottleneck in the manufacturing and deployment of vaccines.\nTo address this problem, in 2013 the U.S. federal government created the Fill Finish Manufacturing Network, a network of third-party provider contracts intended to perform fill and finish operations for vaccines against future infectious diseases. As part of its response to the COVID-19 pandemic, the UK government has provided financial support for fill and finish operations.", "Engineering,_Manufacturing": 0.9997791648, "qwen": "Yes"}
{"id": "17107809", "revid": "12311825", "url": "https://en.wikipedia.org/wiki?curid=17107809", "title": "Induction brazing", "text": "Induction brazing is a process in which two or more materials are joined together by a filler metal that has a lower melting point than the base materials using induction heating. In induction heating, usually ferrous materials are heated rapidly from the electromagnetic field that is created by the alternating current from an induction coil.\nMaterials and applications.\n\"Induction brazing is suitable for many metallic materials, with magnetic materials being heated more readily. Where ceramic materials are involved, heating will most likely occur by conduction from surrounding metallic parts, or the use of a susceptor\" (Sue Dunkerton, 1).\nAccording to Ambrell Group Application Labs talking about filler metals: Silver is frequently used for induction brazing because of its low melting point. Silver-copper eutectic brazes have melting temperatures between 1100°F and 1650°F. Aluminum braze, the least common, has a melting temperature of 1050°F to 1140°F. Copper braze, the least expensive, has a melting temperature of 1300°F to 2150°F. (p1)\nThe filler can be manually applied but because of the more common semiautomatic production a preloaded joint is more commonly used to speed the operation and help to keep a more uniform bond.\nBenefits.\nThere are specific reasons to use induction heating for industrial brazing. These include selective heating, better joint quality, reduced oxidation and acid cleaning, faster heating cycles, more consistent results and suitability for large volume production.\nSelective heating.\nInduction heating can be targeted to provide heat to very small areas within tight production tolerances. Only those areas of the part in close proximity to the joint are heated; the rest of the part is not affected. Since there is no direct contact with the part, there is no opportunity for breakage. The life of the fixturing is substantially increased because problems due to repeated exposure to heat (such as distortion and metal fatigue) are eliminated. This advantage becomes particularly important with high-temperature brazing processes.\nWith efficient coil design, careful fixturing and consistent part placement, it is possible to simultaneously provide heat in different areas of the same part\nBetter quality joints.\nInduction heating produces clean, leak proof joints by preventing the filler from flowing in areas that it shouldn't flow. This ability to create clean and controllable joints is one of the reasons that induction brazing is being used extensively for high-precision, high-reliability applications.\nReduced oxidation and cleaning.\nFlame heating in a normal atmosphere causes oxidation, scaling and carbon build up on the parts. To clean the parts, applications of joint-weakening flux and expensive acid cleaning baths have traditionally been required. Batch vacuum furnaces solve these problems, but have significant limitations of their own because of their large size, poor efficiency and lack of quality control. Brazing with induction reduces both oxidation and costly cleaning requirements, especially when a rapid cool-down cycle is used.\nFast heating cycles.\nBecause the induction heating cycle is very short in comparison to flame brazing, more parts can be processed in the same amount of time, and less heat is released to the surrounding environment.\n“An induction brazing system quickly delivers highly localized heat to minimize part warpage and distortion. Brazing in a controlled vacuum or in an inert protective atmosphere can significantly improve overall part quality and eliminate costly part cleaning procedures” (Induction Atmospheres, 1).\nConsistent results.\nInduction brazing is a very repeatable process because variables such as time, temperature, alloy, fixturing, and part positioning are very controllable. The internal power supply of the RF power supply can be used to control cycle time, and temperature control can be accomplished with pyrometers, visual temperature sensors or thermocouples.\nFor processes, which involve medium to high production runs of the same parts, an automated part handling system is often utilized to further improve consistency and maximize productivity.\nFor the most part, induction brazing and soldering is done in an open-air environment but it can also be done in a controlled atmosphere when necessary to keep the parts completely clean and free of oxidation.\nInduction brazing generally works best with two pieces of similar metal. Dissimilar metals can also be joined by induction heating but they require special attention and techniques. This is due to differences in the materials' resistivity, relative magnetic permeability and coefficients of thermal expansion. (p1)\nGeneral temperatures and times.\nSource: ", "Engineering,_Manufacturing": 1.0000075102, "qwen": "Yes"}
{"id": "17117300", "revid": "4173550", "url": "https://en.wikipedia.org/wiki?curid=17117300", "title": "Sustainable packaging", "text": "Sustainable packaging is the development and use of packaging which results in improved sustainability. This involves increased use of life cycle inventory (LCI) and life cycle assessment (LCA) to help guide the use of packaging which reduces the environmental impact and ecological footprint. It includes a look at the whole of the supply chain: from basic function, to marketing, and then through to end of life (LCA) and rebirth. Additionally, an eco-cost to value ratio can be useful\nThe goals are to improve the long term viability and quality of life for humans and the longevity of natural ecosystems. Sustainable packaging must meet the functional and economic needs of the present without compromising the ability of future generations to meet their own needs. Sustainability is not necessarily an end state but is a continuing process of improvement.\nSustainable packaging is a relatively new addition to the environmental considerations for packaging (see Packaging and labeling). It requires more analysis and documentation to look at the package design, choice of materials, processing, and life-cycle. This is not just the vague \"green movement\" that many businesses and companies have been trying to include over the past years. Companies implementing eco-friendly actions are reducing their carbon footprint, using more recycled materials and reusing more package components. They often encourage suppliers, contract packagers, and distributors to do likewise.\nEnvironmental marketing claims on packages need to be made (and read) with caution. Ambiguous greenwashing titles such as \"green packaging\" and \"environmentally friendly\" can be confusing without specific definition. Some regulators, such as the US Federal Trade Commission, are providing guidance to packagers\nCompanies have long been reusing and recycling packaging when economically viable. Using minimal packaging has also been a common goal to help reduce costs. Recent years have accelerated these efforts based on social movements, consumer pressure, and regulation. All phases of packaging, distribution, and logistics are included.\nSustainable packaging is not focused on just recycling. Just as packaging is not the only eco target, although it is still top of mind for many. Right or wrong, the packaging is frequently scrutinized and used as the measure of a company's overall sustainability, even though it may contribute only a small percentage to the total eco-impact compared to other things, such as transportation, and water and energy use.\nEnvironmental Impacts.\nImpacts of packaging originate from three main stages including feedstock sourcing, production of polymers and packaging, and the end of life treatment of the packaging. Emissions from each stage contribute to climate change, air pollution, acidification, and other environmental issues. Food waste is another prominent issue as one third of food meant for human consumption is lost. Sustainable packaging aims to address properties of food, for example chemical and microbiological properties, in order to limit packaging and food waste.\nCriteria.\nThe criteria for ranking and comparing packaging based on their sustainability is an active area of development. General guidance, metrics, checklists, and scorecards are being published by several groups.\nGovernment, standards organizations, consumers, retailers, and packagers are considering several types of criteria.\nEach organization words the goals and targets a little differently. In general, the broad goals of sustainable packaging are:\nSpecific factors for sustainable design of packaging may include:\nThe chosen criteria are often used best as a basis of comparison for two or more similar packaging designs; not as an absolute success or failure. Such a multi-variable comparison is often presented as a radar chart (spider chart, star chart, etc.).\nBenefits.\nSome aspects of environmentally sound packaging are required by regulators while others are decisions made by individual packagers. Investors, employees, management, and customers can influence corporate decisions and help set policies. When investors seek to purchase stock, companies known for their positive environmental policy can be attractive. Potential stockholders and investors see this as a solid decision: lower environmental risks lead to more capital at cheaper rates. Companies that highlight their environmental status to consumers can boost sales as well as product reputation. Going green is often a sound investment that can pay off.\nAlongside the environmental benefits of adopting sustainable packaging, eco-friendly packaging can increase sales, reduce packaging cost, and increase the image of a company's brand alongside the rising awareness spread regarding environmental impact. There has also been found a direct correlation between a company's implementation of sustainable packaging and a more sustainable supply chain management. Alternatives such as bio-based plastics that are abundant, low cost, and biodegradable, offer a possibility of reducing use of petroleum resources and carbon dioxide emissions.\nAlternatives to conventional plastics.\nPlastic packages or plastic components are sometimes part of a valid environmental solution. Other times, alternatives to petroleum and natural gas based plastic are desirable.\nMaterials have been developed or used for packaging without plastics, especially for use-cases in which packaging can't be phased-out – such as with policies for national grocery store requirements – for being needed for preserving food products or other purposes. \nA plant proteins-based biodegradable packaging alternative to plastic was developed based on research about spider silk which is known for its high strength and similar on the molecular level.\nResearchers at the Agricultural Research Service are looking into using dairy-based films as an alternative to petroleum-based packaging. Instead of being made of synthetic polymers, these dairy-based films would be composed of proteins such as casein and whey, which are found in milk. The films would be biodegradable and offer better oxygen barriers than synthetic, chemical-based films. More research must be done to improve the water barrier quality of the dairy-based film, but advances in sustainable packaging are actively being pursued.\nSustainable packaging policy cannot be individualized by a specific product. Effective legislation would need to include alternatives to many products, not just a select few; otherwise, the positive impacts of sustainable packing will not be as effective as they need in order to propel a significant reduction of plastic packaging. Finding alternatives can reduce greenhouse gas emissions from unsustainable packaging production and reduce dangerous chemical by-products of unsustainable packaging practices.\nAnother alternative to commonly used petroleum plastics are bio-based plastics. Examples of bio-based plastics include natural biopolymers and polymers synthesized from natural feedstock monomers, which can be extracted from plants, animals, or microorganisms. A polymer that is bio-based and used to make plastic materials is not necessarily compostable or bio-degradable. Natural biopolymers can be often biodegraded in the natural environment while only a few bio-based monomer bio-based plastics can be. Bio-based plastics are a more sustainable option in comparison to their petroleum based counterparts, yet they only account for 1% of plastics produced annually as of 2020.\nCosts.\nThe process of engineering more environmentally acceptable packages can include consideration of the costs. Some companies claim that their environmental packaging program is cost effective. Some alternative materials that are recycled/recyclable and/or less damaging to the environment can lead to companies incurring increased costs. Though this is common when any product begins to carry the true cost of its production (producer pays, producer responsibility laws, take-back laws). There may be an expensive and lengthy process before the new forms of packaging are deemed safe to the public, and approval may take up to two years. It is important to note here, that for most of the developed world, tightening legislation, and changes in major retailer demand (Walmart's Sustainable Packaging Scorecard for example) the question is no longer \"if\" products and packaging should become more sustainable, but how-to and how-soon to do it.\nISO standards.\nThe ISO's series of standards relating to packaging and the environment were published in 2013:\nCriticism.\nEfforts toward “greener” packaging are supported in the sustainability community; however, these are often viewed only as incremental steps and not as an end. Some people foresee a true sustainable steady state economy that may be very different from today's: greatly reduced energy usage, minimal ecological footprint, fewer consumer packaged goods, local purchasing with short food supply chains, little processed foods, etc.\nLess packaging would be needed in a sustainable carbon neutral economy, which means that fewer packaging options would exist and simpler packaging forms may be necessary.", "Engineering,_Manufacturing": 0.933339417, "qwen": "Yes"}
{"id": "17127133", "revid": "35498457", "url": "https://en.wikipedia.org/wiki?curid=17127133", "title": "Automobile safety rating", "text": "An automobile safety rating is a grade given by a testing organisation to a motor vehicle indicating the safety of occupants in the event of a motor vehicle crash, like with the New Car Assessment Program.\nAustralia.\nIn Australia, vehicle safety ratings are provided by ANCAP whose procedures are similar to Euro NCAP.\nANCAP took in 1999 some part of Euro NCAP procedures.\nIn 2018, ANCAP adopted the Euro NCAP protocols, with the scoring tweaked to the local conditions.\nEurope.\nIn Europe, vehicle safety ratings are provided by Euro NCAP.\nEuro NCAP provides motoring consumers with a realistic and independent assessment of the safety performance of some of the most popular cars sold in Europe.\nEstablished in 1997 and now backed by seven European Governments, the European Commission and motoring and consumer organisations in every EU country, Euro NCAP has rapidly become a catalyst for encouraging significant safety improvements to new car design.\nGlobal.\nIn the world, there are nine New Car Assessment Programs.\nEight out of the nine test programs makes their vehicle safety ratings with a count of stars included in the range (1 to 5 stars). \nOne test program, IIHS, makes a four level rating: Good, Acceptable, Marginal and Poor.\nThe differences between those various test programs include the range of tests and test configurations, the final rating computation, and the specification of models available in different markets.\nLatin America.\nSince 2010, Latin NCAP has been rating new cars for Latin America and the Caribbean with procedures similar to the ones used by Euro NCAP.\nLatin NCAP results cannot be compared to Euro NCAP results:\nEuro NCAP has 5 ratings: Frontal off-set, side, pole, whiplash and pedestrian tests, while Latin NCAP has 2: frontal off-set crash test and side impact test. Latin NCAP 2020-2022 is similar to Euro NCAP 2014.\nThe frontal crash test of Latin NCAP is similar to the frontal crash test of Euro NCAP.\nUnited States.\nIn the U.S., an NCAP which provides vehicle safety ratings is run by the National Highway Traffic Safety Administration.", "Engineering,_Manufacturing": 0.9190542102, "qwen": "Yes"}
{"id": "30390096", "revid": "1215485", "url": "https://en.wikipedia.org/wiki?curid=30390096", "title": "Collegium of Manufacturing", "text": "The Collegium of Manufacturing (\"Manufaktur-kollegia\"; also College) was an executive body in the Russian Empire from 1722, when the Collegium of Mining and Manufacturing split into two.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "15565331", "revid": "7770027", "url": "https://en.wikipedia.org/wiki?curid=15565331", "title": "Projected tolerance zone", "text": "In geometric dimensioning and tolerancing, a projected tolerance zone is defined to predict the final dimensions and locations of features on a component or assembly subject to tolerance stack-up.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "15582121", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=15582121", "title": "Leidolf", "text": "Leidolf was a manufacturer of optical equipment situated in Wetzlar, Germany. It was founded by Rudolf Leidolf in 1921, initially producing lenses for microscopes. In 1948 camera production was started and in 1962 the factory ceased operations. Leidolf is in no way related to Leitz (the manufacturer of Leica), even though Wetzlar has been the historical location for both companies. The company would later be acquired by Adams, producing the Adams model 351 and 352 sold by Montgomery Ward, before going bankrupt.", "Engineering,_Manufacturing": 0.9999560118, "qwen": "Yes"}
{"id": "21578440", "revid": "575347", "url": "https://en.wikipedia.org/wiki?curid=21578440", "title": "Virtual product development", "text": "Virtual product development (VPD) is the practice of developing and prototyping products in a completely digital 2D/3D environment. VPD has four main components: \nVPD typically takes place in a collaborative, web-based environment that brings together designers, customers/consumers, and value chain partners around a single source of real-time product \"truth\". VPD enables practitioners to arrive at the right idea more quickly, and to accurately predict its performance in both manufacturing and retail settings, ultimately minimizing time to value, market failure potential, and product development costs.\nVirtual process planning is a relatively new concept for manufacturing companies, although the concept has been in use for the construction industry for several years. BIM (building information modeling) is the system used by many construction, architectural and contracting firms. The detail and scheduling aspects are some of the more valuable aspects of the system. By utilizing virtual process planning, the entire production process can be designed to both maximize efficiency and avoid the trial and error method employed by most manufacturers.\nVarious software exists with differing levels of information. The placement of work stations, inventory, personnel and equipment can be valuable for space planning. The interaction of the previously mentioned can also be investigated, allowing the user to identify potential issues from safety, quality and ergonomic standpoints.\nVPD is a result of constant efforts in a direction to overcome the limitations of conventional testing procedures. VPD allows a designer to take important design decisions at early stages based on test results, giving control over cost. ‘Virtual product development’ is a strategy for coordinating technology, processes and people to enhance the established product development process. It is a gradual process that efficiently builds up a product virtually. Thus any changes to be made in its design can be reflected into its physical properties, supply chain, distribution channel and ultimately into the customer view; without physically manufacturing the product.\nVPD encompasses a wide variety of software tools to cover a product from the conception to the final design and even manufacturing. This path consists of various processes to be carried out at manufacturing level, testing procedures and the final design which is modified automatically based on the test results. One of the major advantages of VPD is its computer brain capability, which can simulate various complex load conditions at a time. Non-linear load conditions are not always possible to create at the testing centre where the prototypes are being tested in conventional testing methods. These complex conditions, if accommodated during testing, can yield more reliable product form.", "Engineering,_Manufacturing": 0.9999946356, "qwen": "Yes"}
{"id": "21586164", "revid": "41049936", "url": "https://en.wikipedia.org/wiki?curid=21586164", "title": "Shell molding", "text": "Shell molding, also known as shell-mold casting, is an expendable mold casting process that uses resin covered sand to form the mold. As compared to sand casting, this process has better dimensional accuracy, a higher productivity rate, and lower labour requirements. It is used for small to medium parts that require high precision. Shell molding was developed as a manufacturing process during the mid-20th century in Germany. It was invented by German engineer Johannes Croning. Shell mold casting is a metal casting process similar to sand casting, in that molten metal is poured into an expendable mold. However, in shell mold casting, the mold is a thin-walled shell created from applying a sand-resin mixture around a pattern. The pattern, a metal piece in the shape of the desired part, is reused to form multiple shell molds. A reusable pattern allows for higher production rates, while the disposable molds enable complex geometries to be cast. Shell mold casting requires the use of a metal pattern, oven, sand-resin mixture, dump box, and molten metal.\nShell mold casting allows the use of both ferrous and non-ferrous metals, most commonly using cast iron, carbon steel, alloy steel, stainless steel, aluminium alloys, and copper alloys. Typical parts are small-to-medium in size and require high accuracy, such as gear housings, cylinder heads, connecting rods, and lever arms.\nThe shell mold casting process consists of the following steps:\nPattern creation - A two-piece metal pattern is created in the shape of the desired part, typically from iron or steel. Other materials are sometimes used, such as aluminium for low volume production or graphite for casting reactive materials.\nMold creation - First, each pattern half is heated to 175-370 °C (350-700 °F) and coated with a lubricant to facilitate removal. Next, the heated pattern is clamped to a dump box, which contains a mixture of sand and a resin binder. The dump box is inverted, allowing this sand-resin mixture to coat the pattern. The heated pattern partially cures the mixture, which now forms a shell around the pattern. Each pattern half and surrounding shell is cured to completion in an oven and then the shell is ejected from the pattern.\nmold assembly - The two shell halves are joined together and securely clamped to form the complete shell mold. If any cores are required, they are inserted prior to closing the mold. The shell mold is then placed into a flask and supported by a backing material.\nPouring - The mold is securely clamped together while the molten metal is poured from a ladle into the gating system and fills the mold cavity.\nCooling - After the mold has been filled, the molten metal is allowed to cool and solidify into the shape of the final casting.\nCasting removal - After the molten metal has cooled, the mold can be broken and the casting removed. Trimming and cleaning processes are required to remove any excess metal from the feed system and any sand from the mold.\nExamples of shell molded items include gear housings, cylinder heads and connecting rods. It is also used to make high-precision molding cores.\nProcess.\nThe process of creating a shell mold consists of six steps:\nThe machine that is used for this process is called a \"shell molding machine\". It heats the pattern, applies the sand mixture, and bakes the shell.\nDetails.\nSetup and production of shell mold patterns takes weeks, after which an output of 5–50 pieces/hr-mold is attainable. Common materials include cast iron, aluminum and copper alloys. Aluminum and magnesium products average about as a normal limit, but it is possible to cast items in the range. The small end of the limit is . Depending on the material, the thinnest cross-section castable is . The minimum draft is 0.25 to 0.5 degrees.\nTypical tolerances are 0.005 mm/mm or in/in because the sand compound is designed to barely shrink and a metal pattern is used. The cast surface finish is 0.3–4.0 micrometers (50–150 μin) because a finer sand is used. The resin also assists in forming a very smooth surface. The process, in general, produces very consistent castings from one casting to the next.\nThe sand-resin mix can be recycled by burning off the resin at high temperatures.\nAdvantages and disadvantages.\nAdvantages\nDisadvantages\nApplications.\nCylinder head, connecting rod, Engine blocks and manifolds, machine bases.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "21588737", "revid": "4441371", "url": "https://en.wikipedia.org/wiki?curid=21588737", "title": "List of number-one digital tracks of 2008 (Australia)", "text": "The ARIA Digital Track Chart ranks the best-performing digital tracks of Australia. It is published by Australian Recording Industry Association (ARIA), an organisation who collects music data for the weekly ARIA Charts.\nTo be eligible to appear on the chart, the recording must be a single not an EP and only paid downloads counted from downloadable outlets.", "Engineering,_Manufacturing": 0.9999959469, "qwen": "Yes"}
{"id": "21588805", "revid": "4441371", "url": "https://en.wikipedia.org/wiki?curid=21588805", "title": "List of number-one digital tracks of 2009 (Australia)", "text": "The ARIA Digital Track Chart ranks the best-performing digital tracks of Australia. It is published by Australian Recording Industry Association (ARIA), an organisation who collects music data for the weekly ARIA Charts.\nTo be eligible to appear on the chart, the recording must be a single not an EP and only paid downloads counted from downloadable outlets.", "Engineering,_Manufacturing": 0.9999959469, "qwen": "Yes"}
{"id": "2971012", "revid": "1146303747", "url": "https://en.wikipedia.org/wiki?curid=2971012", "title": "Manufacturing process management", "text": "Manufacturing process management (MPM) is a collection of technologies and methods used to define how products are to be manufactured. MPM differs from ERP/MRP which is used to plan the ordering of materials and other resources, set manufacturing schedules, and compile cost data.\nA cornerstone of MPM is the central repository for the integration of all these tools and activities aids in the exploration of alternative production line scenarios; making assembly lines more efficient with the aim of reduced lead time to product launch, shorter product times and reduced work in progress (WIP) inventories as well as allowing rapid response to product or product changes.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "39416662", "revid": "1169531452", "url": "https://en.wikipedia.org/wiki?curid=39416662", "title": "Gray Tools", "text": "Gray Tools is a Canadian professional tool company based in Brampton, Ontario. Founded in 1912 by Alex Gray (1883-1969), Gray Tools is Canada's largest professional tool manufacturing company, with 4000 industrial products available.\nHistory.\nGray Tools Canada was founded in 1912 by Alex Gray as a machinery equipment supplier. As the automobile industry was starting up, Gray began making automobile manufacturing tools and tool kits specific to the automobile companies in nearby Detroit. \nIn May 2012, President and owner Alex Gray III sold the company to Garry Nuttall and Frank Dominguez. Alex Gray III remains with the company as chairman.\nAs of 2013, the company employed 60 people at its head office in Brampton, Ontario, where all manufacturing is done. Company warehouses are located in Brampton and Edmonton, Alberta.\nGray Tools celebrated its 100th birthday by making a large donation of tools and equipment to local schools and by initiating the Gray Tools Canada Highest Standard Achievement Award, presented to a student with exceptional success in vocational education.\nProducts.\nThe main focus at Gray tools is the professional hand tool line. Tool storage and organization is a subsidiary product line. A cheaper line of foreign-made tools sold as Dynamic are made to compete with the middle range tool marketplace.", "Engineering,_Manufacturing": 1.0000050068, "qwen": "Yes"}
{"id": "39436522", "revid": "12821096", "url": "https://en.wikipedia.org/wiki?curid=39436522", "title": "Jewelry model", "text": "A jewelry model is a master design that is copied to make many similar pieces of jewelry. The model may either be a piece of actual finished jewelry or a low-cost blank fashioned from base metal. In either case, the model is used to create the casting mold from which all subsequent pieces are made.\nPrefabricated models are available from a number of sources to supply the hobby and high-volume jewelry manufacture trade.", "Engineering,_Manufacturing": 1.0000010729, "qwen": "Yes"}
{"id": "54190221", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=54190221", "title": "Voestalpine Böhler Welding", "text": "voestalpine Böhler Welding is a manufacturer of welding consumables (joint welding, maintenance, repair and overlay welding and brazing), welding equipment and accessories with headquarters in Düsseldorf. The company owns over 50 subsidiaries in more than 25 countries, 2,300 employees, customers in approximately 150 countries and more than 1,000 distribution partners.\nThe company is a business segment of the voestalpine AG Metal Engineering Division.\nThe company offers extensive technical consultation and individual solutions for industrial welding and soldering applications. It has three specialized and dedicated brands for joint welding, maintenance and cladding, and brazing and soldering.\nProducts.\nAlloys", "Engineering,_Manufacturing": 0.999997735, "qwen": "Yes"}
{"id": "921004", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=921004", "title": "Displacer beast", "text": "A displacer beast is a fictional evil feline creature created for the \"Dungeons & Dragons\" role-playing game in 1975; it has subsequently been included in every edition of the game to the present day.\nDescription.\nA displacer beast is a magical six-legged black panther-like feline with a pair of tentacles growing from its shoulders; the beast has an innate \"displacement\" ability, causing it appear to be several feet away from its actual location. \"These mighty predators are typically found in the Feywild\", \"an alternate plane of existence\" home to \"D&D\"'s version of fairies.\nPublication history.\n\"Dungeons & Dragons\" (1974–1976).\nThe displacer beast was created for \"Dungeons & Dragons\", first introduced in the game's supplement, \"Greyhawk\" (1975), as \"a puma-like creature with six legs and a pair of tentacles which grow from its shoulders.\" The concept of the creature was borrowed from A. E. van Vogt's 1939 science fiction story \"Black Destroyer\", which described a feline-like creature called a coeurl. Van Vogt later incorporated the coeurl into the novel \"The Voyage of the Space Beagle\" (1950).\n\"Advanced Dungeons & Dragons\" 1st edition (1977–1988).\nThe displacer beast appears in the first edition \"Monster Manual\" (1977), where it is described as a vaguely puma-like beast that always appears to be three feet away from its actual position. David M. Ewalt, in his book \"Of Dice and Men\", discussed several monsters appearing in the original \"Monster Manual\", describing displacer beasts as looking like \"pumas with thorn-covered tentacles growing out of their shoulders\".\nThe displacer beast was detailed in \"Dragon\" #109 (May 1986), in the \"Ecology of the Displacer Beast\".\n\"Dungeons & Dragons\" (1977–1999).\nThis edition of the \"D&D\" game included its own version of the displacer beast, in the \"Dungeons & Dragons Basic Set\" (1977), and \"Expert Set\" (1981 & 1983), and was also later featured in the \"Dungeons & Dragons Game\" set (1991), the \"Dungeons & Dragons Rules Cyclopedia\" (1991), the \"Classic Dungeons & Dragons Game\" set (1994), and the \"Dungeons & Dragons Adventure Game\" set (1999).\n\"Advanced Dungeons & Dragons\" 2nd edition (1989–1999).\nThe displacer beast appears in the \"Monstrous Compendium Volume One\" (1989), and is reprinted in the \"Monstrous Manual\" (1993).\n\"Dungeons & Dragons\" 3.0 & 3.5 editions (2000–2007).\nThe displacer beast appears in the 3rd edition \"Monster Manual\" (2000) and then in the 3.5 edition \"Monster Manual\" (2003). This edition also described the displacer beast pack lord. For this edition, Wizards of the Coast considered the displacer beast to be an original product of \"D&D\" and was therefore categorized as a \"Product Identity\"; as such it was not released under its Open Game License.\n\"Dungeons & Dragons\" 4th edition (2008–2013).\nThe displacer beast appears in the 4th edition \"Monster Manual\" (2008), and again a description is included for the displacer beast packlord.\n\"Dungeons & Dragons\" 5th edition (2014).\nThe displacer beast appears in the 5th edition \"Monster Manual\" (2014). It is considered a copyrighted original creation for the \"Dungeons & Dragons\" game.\nOther media.\nA displacer beast appears in the film '. A displacer beast kitten is a ' card created as part of the \"\" crossover.\nReception.\nRob Bricken from io9 named the displacer beast as the 2nd most memorable \"D&D\" monster. Reviewers also counted it among the \"most iconic\" and \"fan-favorite\" monsters of the game. It was considered an \"old-school\" and \"most enduring\" monster, having been part of the game from its earliest stages. Author Ben Riggs remarked on the movie version of the displacer beast: \"The design of the creature is just so fantastic. It's creepy. Even though it's a panther with a couple tentacles, at first you're creeped out\". David M. Marshall remarked that the displacer beast is one of the elements \"which disrupts the roughly period [medieval] atmosphere of the game\".", "Engineering,_Manufacturing": 0.9978930354, "qwen": "Yes"}
{"id": "922087", "revid": "8390765", "url": "https://en.wikipedia.org/wiki?curid=922087", "title": "Bolted joint", "text": "A bolted joint is one of the most common elements in construction and machine design. It consists of a male threaded fastener (e. g., a bolt) that captures and joins other parts, secured with a matching female screw thread. There are two main types of bolted joint designs: tension joints and shear joints.\nJoint types.\nIn a tension joint, the bolt and clamped components of the joint are designed to transfer an applied tension load through the joint by way of the clamped components by the design of a proper balance of joint and bolt stiffness. The joint should be designed such that the clamp load is never overcome by the external tension forces acting to separate the joint. If the external tension forces overcome the clamp load (bolt preload) the clamped joint components will separate, allowing relative motion of the components.\nThe second type of bolted joint transfers the applied load in shear of the bolt shank and relies on the shear strength of the bolt. Tension loads on such a joint are only incidental. A preload is still applied but consideration of joint flexibility is not as critical as in the case where loads are transmitted through the joint in tension. Other such shear joints do not employ a preload on the bolt as they are designed to allow rotation of the joint about the bolt but use other methods of maintaining bolt/joint integrity. Joints that allow rotation include clevis linkages, and rely on a locking mechanism (like lock washers, thread adhesives, and lock nuts).\nProper joint design and bolt preload provides useful properties:\nIn both the tension and shear joint design cases, some level of tension preload in the bolt and resulting compression preload in the clamped components is essential to the joint integrity. The preload target can be achieved by a variety of methods: applying a measured torque to the bolt, measuring bolt extension, heating to expand the bolt then turning the nut down, torquing the bolt to the yield point, testing ultrasonically, or by applying a certain number of degrees of relative rotation of the threaded components. Each method has a range of uncertainties associated with it, some of which are very substantial.\nTheory.\nTypically, a bolt is tensioned (preloaded) by the application of a torque to either the bolt head or the nut. The applied torque causes the bolt to \"climb\" the thread causing a tensioning of the bolt and an equivalent compression in the components being fastened by the bolt. The preload developed in a bolt is due to the applied torque and is a function of the bolt diameter, the geometry of the threads, and the coefficients of friction that exist in the threads and under the torqued bolt head or nut. The stiffness of the components clamped by the bolt has no relation to the preload that is developed by the torque. The relative stiffness of the bolt and the clamped joint components do, however, determine the fraction of the external tension load that the bolt will carry and that in turn determines preload needed to prevent joint separation and by that means to reduce the range of stress the bolt experiences as the tension load is repeatedly applied. This determines the durability of the bolt when subjected to repeated tension loads. Maintaining a sufficient joint preload also prevents relative slippage of the joint components that would produce fretting wear that could result in a fatigue failure of those parts.\nThe clamp load, also called preload of a fastener, is created when a torque is applied, and so develops a tensile preload that is generally a substantial percentage of the fastener's proof strength. Fasteners are manufactured to various standards that define, among other things, their strength. \"Torque charts\" are available to specify the required torque for a given fastener based on its \"property class\" (fineness of manufacture and fit) and \"grade\" (tensile strength).\nWhen a fastener is torqued, a tension preload develops in the bolt and an equal compressive preload develops in the parts being fastened. This can be modeled as a spring-like assembly that has some assumed distribution of compressive strain in the clamped joint components. When an external tension load is applied, it relieves the compressive strains induced by the preload in the clamped components, hence the preload acting on the compressed joint components provides the external tension load with a path (through the joint) other than through the bolt. In a well designed joint, perhaps 80-90% of the externally applied tension load will pass through the joint and the remainder through the bolt. This reduces the fatigue loading of the bolt.\nWhen the fastened parts are less stiff than the fastener (those that use soft, compressed gaskets for example), this model breaks down and the fastener is subjected to a tension load that is the sum of the tension preload and the external tension load.\nIn some applications, joints are designed so that the fastener eventually fails before more expensive components. In this case, replacing an existing fastener with a higher strength fastener can result in equipment damage. Thus, it is generally good practice to replace old fasteners with new fasteners of the same grade.\nCalculating the torque.\nEngineered joints require the torque to be chosen to provide the correct tension preload. Applying the torque to fasteners is commonly achieved using a torque wrench. The required torque value for a particular fastener application may be quoted in the published standard document, defined by the manufacturer or calculated. The side of the threaded fastening having the least friction should receive torque while the other side is counter-held or otherwise prevented from turning.\nA common relationship used to calculate the torque for a desired preload takes into account the thread geometry and friction in the threads and under the bolt head or nut. The following assumes standard ISO or National Standard bolts and threads are used:\nwhere \nThe nut factor K accounts for the thread geometry, friction, pitch. When ISO and Unified National Standard threads are used the nut factor is:\nwhere\nWhen formula_10 = formula_12 = 0.15, the dimensions used correspond to any size coarse or fine bolt, and the nut factor is K ≈ 0.20, the torque/preload relationship becomes:\nA study of the effect of torquing two samples, one lubricated and the other unlubricated, 1/2 in.- 20 UNF bolts to 800 lb-in, produced the same mean preload of 7700 lbf. The preloads for the unlubricated bolt sample had a standard deviation from the mean value of 1100 lbf, whereas the lubricated sample had a standard deviation of 680 lbf. If the preload value and torques are used in the above relation to solve for the nut factor it is found to be K = 0.208, which is very close to the recommended value of 0.20\nThe preferred bolt preload for structural applications should be at least 75% of the fastener's proof load for the higher strength fasteners and as high as 90% of the proof load for permanent fasteners. To achieve the benefits of the preloading, the clamping force must be higher than the joint separation load. For some joints, multiple fasteners are required to secure the joint; these are all hand tightened before the final torque is applied to ensure an even joint seating.\nThe preload achieved by torquing a bolt is caused by the part of the torque that is effective. Friction in the threads and under the nut or bolt head uses up some fraction of the applied torque. Much of the torque applied is lost overcoming friction under the torqued bolt head or nut (50%) and in the threads (40%). The remaining 10% of the applied torque does useful work in stretching the bolt and providing the preload. Initially, as the torque is applied, it must overcome static friction under the head of the bolt or nut (depending on which end is being torqued) and also in the threads. Finally, dynamic friction prevails and the torque is distributed in a 50/40/10 % manner as the bolt is tensioned. The torque value is dependent on the friction produced in the threads and under the torqued bolt head or nut and the fastened material or washer if used. This friction can be affected by the application of a lubricant or any plating (e.g. cadmium or zinc) applied to the threads, and the fastener's standard defines whether the torque value is for dry or lubricated threading, as lubrication can reduce the torque value by 15% to 25%; lubricating a fastener designed to be torqued dry could over-tighten it, which may damage threading or stretch the fastener beyond its elastic limit, thereby reducing its clamping ability.\nEither the bolt head or the nut can be torqued. If one has a larger bearing area or coefficient of friction it will require more torque to provide the same target preload. Fasteners should only be torqued if they are fitted in clearance holes.\nTorque wrenches do not give a direct measurement of the preload in the bolt.\nMore accurate methods for determining the preload rely on defining or measuring the \"screw extension\" from the nut. Alternatively, measurement of the angular rotation of the nut can serve as the basis for defining screw extension based on the fastener's thread pitch. Measuring the screw extension directly allows the clamping force to be very accurately calculated. This can be achieved using a dial test indicator, reading deflection at the fastener tail, using a strain gauge, or ultrasonic length measurement.\nBolt preload can also be controlled by torquing the bolt to the point of yielding. Under some circumstances, a skilled operator can feel the drop off of the work required to turn the torque wrench as the material of the bolt begins to yield. At that point the bolt has a preload determined by the bolt area and the yield strength of the bolt material. This technique can be more accurately executed by specially built machines. Because this method only works for very high preloads and requires comparatively expensive tooling, it is only commonly used for specific applications, primarily in high performance engines.\nThere is no (as yet) simple method to measure the tension of a fastener in situ. All methods, from the least to most accurate, involve first relaxing the fastener, then applying force to it and quantifying the resultant amount of elongation achieved. This is known as 're-torqueing' or 're-tensioning' depending on which technology is employed. \nTechnologies employed in this process can be:\nAn electronic torque wrench is used on the fastener in question, so that the torque applied can be measured as it is increased in magnitude.\nRecent technological developments have enabled tensions to be established (± 1%) by using ultrasonic testing. This provides the same accuracy to that of strain gauging without having to set strain gauges on each fastener.\nAnother method that indicates tension (mainly in erecting steel) involves the use of crush-washers. These are washers that have been drilled and filled with orange RTV. When a given force has been applied (± 10%), orange rubber strands appear.\nLarge-volume users (such as auto makers) frequently use computer-controlled nut drivers. With such machines, the computer is in control of shutting off the torque mechanism when a predetermined value has been reached. Such machines are often used to fit and tighten wheel nuts on an assembly line, and have also been developed for use in mobile plant tire fitting bays on mine sites.\nThread engagement.\n\"Thread engagement\" is the length or number of threads that are engaged between the screw and the female threads. Bolted joints are designed so that the bolt shank fails in tension before the threads fail in shear, but for this to hold true, a minimum thread engagement must be achieved. The following equation defines this minimum thread engagement:\nWhere Le is the thread engagement length, At is the tensile stress area, D is the major diameter of the screw, and p is the pitch. This equation only holds true if the screw and female thread materials are the same. If they are not the same, then the following equations can be used to determine the additional thread length that is required:\nWhere Le2 is the new required thread engagement.\nWhile these formulas give absolute minimum thread engagement, many industries specify that bolted connections be at least fully engaged. For instance, the FAA has determined that in general cases, at least one thread must be protruding from any bolted connection. \nFailure modes.\nWhen doing a failure mode analysis for bolts that have broken, come loose or corroded, careful consideration must be given to the below Failure Modes:\nBolted joints may be used intentionally as sacrificial parts, which are intended to fail before other parts, as in a shear pin.\nLocking mechanisms.\nLocking mechanisms keep bolted joints from coming loose. They are required when vibration or joint movement will cause loss of clamp load and joint failure, and in equipment where the security of bolted joints is essential. A prevalent test for the self-loosening behaviour is the Junker test.\nBolt banging.\n\"Bolt banging\" occurs in buildings when bolted joints slip into \"bearing under load\", thus causing a loud and potentially frightening noise resembling a rifle shot that is not, however, of structural significance and does not pose any threat to occupants. \nA bolted joint between two elements may act as a bearing-type joint, or a friction joint. In the friction joint, the elements are clamped together with enough force that the resultant friction between the clamped surfaces prevents them from slipping laterally over each other.\nIn the bearing joint, the bolt itself limits lateral movement of the elements by the shank of the bolt bearing upon the sides of the holes in the clamped elements. Such joints require less clamping force, because a high level of friction between the clamped surfaces is not required. The clearance between the bolt and the holes means that some lateral movement may occur before the bolt bears against the sides of the holes. \nEven when designed as a bearing joint, the surface friction between the clamped elements may be sufficient to resist movement for some time, especially when the building may not yet be fully loaded – thus it operates initially as a friction joint. When the lateral force becomes sufficient to overcome this friction, the clamped elements move until the sides of the holes bear against the shank of the bolt. This movement – \"slip into bearing\" – usually starts and stops very suddenly, often releasing elastic energy in the associated elements, resulting in a loud but harmless bang.", "Engineering,_Manufacturing": 0.999774158, "qwen": "Yes"}
{"id": "848200", "revid": "39872398", "url": "https://en.wikipedia.org/wiki?curid=848200", "title": "Quad flat package", "text": "A quad flat package (QFP) is a surface-mounted integrated circuit package with \"gull wing\" leads extending from each of the four sides. Socketing such packages is rare and through-hole mounting is not possible. Versions ranging from 32 to 304 pins with a pitch ranging from 0.4 to 1.0 mm are common. Other special variants include low-profile QFP (LQFP) and thin QFP (TQFP).\nThe QFP component package type became common in Europe and United States during the early nineties, even though it has been used in Japanese consumer electronics since the seventies. It is often mixed with hole mounted, and sometimes socketed, components on the same printed circuit board (PCB).\nA package related to QFP is plastic leaded chip carrier (PLCC) which is similar but has pins with larger pitch, 1.27 mm (or 1/20 inch), curved up underneath a thicker body to simplify socketing (soldering is also possible). It is commonly used for NOR flash memories and other programmable components.\nLimitations.\nThe quad flat-pack has connections only around the periphery of the package. To increase the number of pins, the spacing was decreased from 50 mil (as found on small outline packages) to 20 and later 12 (1.27 mm, 0.51 mm and 0.30 mm respectively). However, this close lead spacing made solder bridges more likely and put higher demands on the soldering process and alignment of parts during assembly. The later pin grid array (PGA) and ball grid array (BGA) packages, by allowing connections to be made over the area of the package and not just around the edges, allowed for higher pin counts with similar package sizes, and reduced the problems with close lead spacing.\nVariants.\nThe basic form is a flat rectangular (often square) body with leads on four sides but with numerous variation in the design. These differ usually only in lead number, pitch, dimensions, and materials used (usually to improve thermal characteristics). A clear variation is bumpered quad flat package (BQFP) with extensions at the four corners to protect the leads against mechanical damage before the unit is soldered.\nHeat sink quad flat package, \"heatsink very thin quad flat-pack no-leads\" (\"HVQFN\") is a package with no component leads extending from the IC. Pads are spaced along the sides of the IC with an exposed die that can be used as ground. Spacing between pins can vary.\nA thin quad flat pack (TQFP) provides the same benefits as the metric QFP, but is thinner. Regular QFP are 2.0 to 3.8 mm thick depending on size. TQFP packages range from 32 pins with a 0.8 mm lead pitch, in a package 5 mm by 5 mm by 1 mm thick, to 256 pins, 28 mm square, 1.4 mm thick and a lead pitch of 0.4 mm.\nTQFPs help solve issues such as increasing board density, die shrink programs, thin end-product profile and portability. Lead counts range from 32 to 176. Body sizes range from 5 mm x 5 mm to 20  x 20 mm. Copper lead-frames are used in TQFPs. Lead pitches available for TQFPs are 0.4 mm, 0.5 mm, 0.65 mm, 0.8 mm, and 1.0 mm. \"PQFP\", or plastic quad flat pack, is a type of QFP, as is the thinner TQFP package. PQFP packages can vary in thickness from 2.0 mm to 3.8 mm. A low-profile quad flat package (LQFP) is a surface mount integrated circuit package format with component leads extending from each of the four sides. Pins are numbered counter-clockwise from the index dot. Spacing between pins can vary; common spacings are 0.4, 0.5, 0.65 and 0.80 mm intervals.\nSome QFP packages have an exposed pad. The exposed pad is an extra pad underneath or on top of the QFP that may act as a ground connection and/or as a heat sink for the package. The pad is typically 10 or more mm², and with the pad soldered down onto the ground plane, heat is passed into the PCB. This exposed pad also gives a solid ground connection. These type of QFP packages often have a -EP suffix (e.g. a LQFP-EP 64), or they have an odd number of leads, (e.g. a TQFP-101).\nCeramic QFP package.\nCeramic QFP packages come in two variants, CERQUAD and CQFP:\nCERQUAD packages.\nHereby the leadframe is attached between two ceramic layers of the package. The leadframe is attached using glass. This package is a variant of the CERDIP package. CERQUAD packages are the \"low cost\" alternative for CQFP packages, and are mainly used for terrestrial applications.\nMain ceramic package manufacturers are Kyocera, NTK... and offer the full pincount range\nCQFP packages.\nHereby the leads are soldered on top of the package. The package is a multilayer package, and is offered as HTCC (high temperature co-fired ceramic). The number of bonding decks can be one, two or three. Package is finished with a nickel plus a \"thick\" gold layer, except where the leads are soldered and decoupling capacitors are soldered on top of the package. These packages are hermetic. Two methods are used in order to make the hermetic sealing: eutectic gold-tin alloy (melting point 280°C) or seam welding. Seam welding gives rise to significantly less temperature rise in the internal of the package (e.g., the die attach). This package is the main package used for Space projects.\nDue to the large body size of CQFP packages, parasitics are important for this package. Power supply decoupling is improved by having the decoupling capacitors mounted on top of this package. E.g. TI offers 256-pin CQFP packages where decoupling capacitors can be soldered on top of the package E.g. Test-expert 256-pin CQFP packages where decoupling capacitors can be soldered on top of the package.\nThe main ceramic package manufacturers are Kyocera (Japan), NTK (Japan), Test-Expert (Russia), etc. and offer the full pincount range. Maximum pin count is 352 pins.", "Engineering,_Manufacturing": 0.9985356927, "qwen": "Yes"}
{"id": "849762", "revid": "40834146", "url": "https://en.wikipedia.org/wiki?curid=849762", "title": "Economic order quantity", "text": "Economic Order Quantity (EOQ), also known as Financial Purchase Quantity or Economic Buying Quantity (EPQ), is the order quantity that minimizes the total holding costs and ordering costs in inventory management. It is one of the oldest classical production scheduling models. The model was developed by Ford W. Harris in 1913, but R. H. Wilson, a consultant who applied it extensively, and K. Andler are given credit for their in-depth analysis.\nOverview.\nEOQ applies only when demand for a product is constant over the year and each new order is delivered in full when inventory reaches zero. There is a fixed cost for each order placed, regardless of the number of units ordered; an order is assumed to contain only 1 unit. There is also a cost for each unit held in storage, commonly known as holding cost, sometimes expressed as a percentage of the purchase cost of the item. While the EOQ formulation is straightforward there are factors such as transportation rates and quantity discounts to consider in actual application.\nWe want to determine the optimal number of units to order so that we minimize the total cost associated with the purchase, delivery, and storage of the product.\nThe required parameters to the solution are the total demand for the year, the purchase cost for each item, the fixed cost to place the order for a single item and the storage cost for each item per year. Note that the number of times an order is placed will also affect the total cost, though this number can be determined from the other parameters.\nThe total cost function and derivation of EOQ formula.\nThe single-item EOQ formula finds the minimum point of the following cost function:\nTotal Cost = purchase cost or production cost + ordering cost + holding cost\nWhere:\nTo determine the minimum point of the total cost curve, calculate the derivative of the total cost with respect to Q (assume all other variables are constant) and set it equal to 0:\nSolving for Q gives Q* (the optimal order quantity):\nTherefore:\n \nQ* is independent of P; it is a function of only K, D, h.\nThe optimal value Q* may also be found by recognizing that\nwhere the non-negative quadratic term disappears for formula_12 which provides the cost minimum formula_13\nExample.\nEconomic order quantity = formula_14 formula_15 = 400 units\nNumber of orders per year (based on EOQ) formula_16\nTotal cost formula_17\nTotal cost formula_18\nIf we check the total cost for any order quantity other than 400(=EOQ), we will see that the cost is higher. For instance, supposing 500 units per order, then\nTotal cost formula_19\nSimilarly, if we choose 300 for the order quantity, then\nTotal cost formula_20\nThis illustrates that the economic order quantity is always in the best interests of the firm.\nExtensions of the EOQ model.\nQuantity discounts.\nAn important extension to the EOQ model is to accommodate quantity discounts. There are two main types of quantity discounts: (1) all-units and (2) incremental. Here is a numerical example:\nIn order to find the optimal order quantity under different quantity discount schemes, one should use algorithms; these algorithms are developed under the assumption that the EOQ policy is still optimal with quantity discounts. Perera et al. (2017) establish this optimality and fully characterize the (s,S) optimality within the EOQ setting under general cost structures.\nDesign of optimal quantity discount schedules.\nIn presence of a strategic customer, who responds optimally to discount schedules, the design of an optimal quantity discount scheme by the supplier is complex and has to be done carefully. This is particularly so when the demand at the customer is itself uncertain. An interesting effect called the \"reverse bullwhip\" takes place where an increase in consumer demand uncertainty actually reduces order quantity uncertainty at the supplier.\nBackordering costs and multiple items.\nSeveral extensions can be made to the EOQ model, including backordering costs and multiple items. In the case backorders are permitted, the inventory carrying costs per cycle are:\nwhere s is the number of backorders when order quantity Q is delivered and formula_22 is the rate of demand. The backorder cost per cycle is:\nwhere formula_24 and formula_25 are backorder costs, formula_26, T being the cycle length and formula_27. The average annual variable cost is the sum of order costs, holding inventory costs and backorder costs:\nTo minimize formula_29 impose the partial derivatives equal to zero:\nSubstituting the second equation into the first gives the following quadratic equation:\nIf formula_33 either s=0 or formula_34 is optimal. In the first case the optimal lot is given by the classic EOQ formula, in the second case an order is never placed and minimum yearly cost is given by formula_35. If formula_36 or formula_37 formula_38 is optimal, if formula_39 then there shouldn't be any inventory system. If formula_40 solving the preceding quadratic equation yields:\nIf there are backorders the reorder point is: formula_43; with m being the largest integer formula_44 and μ the lead time demand.\nAdditionally, the economic order interval can be determined from the EOQ and the economic production quantity model (which determines the optimal production quantity) can be determined in a similar fashion.\nA version of the model, the Baumol-Tobin model, has also been used to determine the money demand function, where a person's holdings of money balances can be seen in a way parallel to a firm's holdings of inventory.\nMalakooti (2013) has introduced the multi-criteria EOQ models where the criteria could be minimizing the total cost, Order quantity (inventory), and Shortages.\nA version taking the time-value of money into account was developed by Trippi and Lewin.\nImperfect quality.\nAnother important extension of the EOQ model is to consider items with imperfect quality. Salameh and Jaber (2000) are the first to study the imperfect items in an EOQ model very thoroughly. They consider an inventory problem in which the demand is deterministic and there is a fraction of imperfect items in the lot and are screened by the buyer and sold by them at the end of the circle at discount price.", "Engineering,_Manufacturing": 0.9994581342, "qwen": "Yes"}
{"id": "44314961", "revid": "43176118", "url": "https://en.wikipedia.org/wiki?curid=44314961", "title": "EnvisionTEC", "text": "EnvisionTEC is a privately held global company that develops, manufactures and sells more than 40 configurations of desktop and production 3D printers based on seven several distinct process technologies that build objects from digital design files. Founded in 2002, the company now has a corporate headquarters for North America, located in Dearborn, Mich., and International headquarters in Gladbeck, Germany. It also has a production facility in the Greater Los Angeles area, as well as additional facilities in Montreal, for materials research, in Kiev, Ukraine, for software development, and in Woburn, Mass, for robotic 3D printing research and development. Today, the company's 3D Printers are used for mass customized production and to manufacture finished goods, investment casting patterns, tooling, prototypes and more. EnvisionTEC serves a variety of medical, professional and industrial customers. EnvisionTEC has developed large customer niches in the jewelry, dental, hearing aid, medical device, biofabrication and animation industries. EnvisionTEC is one of the few 3D printer companies globally whose products are being used for real production of final end-use parts.\nTechnology.\nSince it filed its first patent in 1999, EnvisionTEC has developed and brought to market several new additive manufacturing technologies used for 3D printing.\nThree of those technologies are based on harnessing light as a tool to cure liquid resin into a three-dimensional object based on a digital design files.\nEnvisionTEC has also been developing and expanding its process technology beyond DLP and light-based curing technologies, too.\nThe company's 3D-Bioplotter series now includes a Starter, Developer and Manufacturing model that extrude materials in three dimensions using pressure. Materials range from a viscous paste to a liquid, and are inserted using syringes moving in three dimensions. Air or mechanical pressure is applied to the syringe, which then deposits a strand of material for the length of movement and time the pressure is applied. Parallel strands are plotted in one layer. For the following layer, the direction of the strands is turned over the center of the object, creating a fine mesh with good mechanical properties and mathematically well-defined porosity. The 3D-Bioplotter is frequently used in biofabrication and is being used in a wide range of medical research. Scientists from Northwestern University, for example, have created 3D printed ovary implants using an EnvisionTEC 3D-Bioplotter that may be used one day to treat women experiencing infertility.\nProducts.\nEnvisionTEC sells more than 40 configurations of 3D Printers that sell for between $6,299 and $1 million. The company's printers are organized into several families of printers: Desktops (Aria, Micro, Vida, Aureus, etc.); Perfactory; cDLM; 3SP; 3D-Bioplotter; and the SLCOM. EnvisionTEC also markets and sells the Viridis3D RAM123 under an \"exclusive strategic partnership.\"\nIn early 2016, EnvisionTEC demonstrated a shift in its strategic direction with the launch of several new models of printers, including the 3D-Bioplotter Starter Series, the SLCOM 1 and RAM123. \"Previously known as pioneers in the 3D printing technology of digital light processing (DLP), the U.S.-German company has managed to redefine itself once again by announcing three new platforms at the event: a new bioprinter, a 3D printer for sandcasting and, perhaps its most substantial unveil, a massive industrial 3D printer dedicated to composite manufacturing,\" according to Engineering.com.\nFounder.\nEnvisionTEC was founded by Hendrik John a German inventor and later managed by John and its current owner, Al Siblani, a Lebanese immigrant who came to the United States to complete his higher education. After earning a bachelor's degree in engineering at Lawrence Technological University and a master's degree in electrical and computer engineering from Wayne State University, both located in Metro Detroit, Siblani entered a 3D printing market still in its infancy. He began working in 1993, for an early 3D printing company, Helisys, that used Laminated Object Manufacturing (LOM) technology to create prototypes for automakers and other commercial customers. Shortly thereafter, he founded Sibco Inc., which provided 3D printing services and materials. In 1996, after mastering the 3D printing technologies and materials at the time, Siblani decided to make his own 3D printing machines using a then-novel idea to cure resins into objects. His first patent submission, which laid the foundation for EnvisionTEC, was filed in 1999. In 2015, Siblani was honored as a finalist for the Ernst & Young Entrepreneur of the Year program for the Michigan and Northwest Ohio region.", "Engineering,_Manufacturing": 0.9999036789, "qwen": "Yes"}
{"id": "1672889", "revid": "42435412", "url": "https://en.wikipedia.org/wiki?curid=1672889", "title": "Solderability", "text": "The solderability of a substrate is a measure of the ease with which a soldered joint can be made to that material. Good solderability requires wetting (low contact angle) of the substrate by the solder.\nOf metals.\nSolderability varies depending on the type of solder alloy under discussion. The discussion that follows applies only to unspecified electronic solders (which may include solders that contain lead, now banned for use in nearly all electronic equipment made or sold in the EU). Solderability when using lead-free alloys can differ significantly from solderability when using lead based alloys.\nNoble metals may be easy to solder but they have brittle joints. The metals in the good category require a large amount of heat therefore oxidation is an issue. To overcome this a flux is required. For carbon steel, low alloy steel, zinc, and nickel the presence of sulfur creates a brittle joint; lower temperatures are used to minimize this problem. The oxides on the surface of aluminium cause wetting issues and special solders must be used to prevent galvanic corrosion issues. Stainless steel and high alloy steel have a low solderability because the chromium alloying element creates oxides that require aggressive fluxes. The only way that the final category of metals can be soldered is by pre-plating them in a metal that is solderable.\nTesting solderability.\nBoth quantitative and qualitative tests for solderability exist.\nThe two most common testing methods are the 'dip and look' method and wetting balance analysis. In both of these tests, the soldered pieces undergo an accelerated aging process before being tested for solderability, to take into consideration the time a component was in storage prior to mounting to final assembly. The dip and look method is a qualitative test. One form of it is specified as Mil-Std-883 Method 2003. On the other hand, the wetting balance analysis is a quantitative test that measures the wetting forces between molten solder and the test surface as a function of time.", "Engineering,_Manufacturing": 0.9997921586, "qwen": "Yes"}
{"id": "39388546", "revid": "1145874762", "url": "https://en.wikipedia.org/wiki?curid=39388546", "title": "Polygonal turning", "text": "Polygonal turning (or polygon turning) is a machining process which allows non-circular forms (polygons) to be machine turned without interrupting the rotation of the raw material. \nTechnical details.\nPolygonally turned parts may have several points, teeth, or other forms at the ends or along their circumference. The technique requires synchronisation of the movement of the polygonal turning mill and the part being machined. Polygonal turning allows rapid production and clean machining of advanced geometries. \nThe polygon turning unit has a multitude of inserts, and is synchronized so that when an insert cuts the turning bar stock, it cuts the bar at the same radial position each time the workpiece rotates. This enables geometries such as hexes, squares and flats to be machined at faster speeds than by milling.\nHistorical notes.\nThe Polygonal Turning Corporation of Marquette, Michigan manufactured shaped joinery products for domestic use during the 1890s.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "39401577", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=39401577", "title": "Spring Back Compensation", "text": "Due to the plastic-elastic characteristic of a metal, it is typical that any deformation of sheet metal at room temperature will have both elastic and plastic deformation. After the metal workpiece is removed from the tool or deformation implement, the elastic deformation will be released and only the plastic deformation will remain. When a metal forming tool is planned and designed to deform a workpiece, the shape imparted by the tool will be a combination of elastic and plastic deformation. The release of the elastic deformation is the spring back often observed at the end of a metal forming process. \nThe spring back has to be compensated to achieve an accurate result.\nUsually, that is realized by overbending the material corresponding to the magnitude of the spring back. That means for the practical side of the bending process; the bending former, enters deeper into the bending prism.\nFor other sheet metal forming operations like drawing, it entails deforming the sheet metal past the planned net shape of the part, so that when the spring back is released from the part, the plastic deformation in that part delivers the desired shape of the part. In the case of complex tools, the spring back has to be already considered in the engineering and construction phases. Therefore, complex software simulations are used. Frequently this is not enough to deliver the desired results. In such cases practical experiments are done, using the trial-and-error plus experience method to correct the tool. However, the results (work pieces) are only stable, if all influencing factors are the same.\nThis mainly includes:\nThe list of factors may be continued. Spring back assessment of final formed products is a difficult problem and is affected by the complexity of the formed shape. The NUMISHEET 93 conference benchmark problem involves the draw bending of a U-channel using three measured parameters. Parameter less approaches have been proposed for more complex geometries but need validation.\nPractical example: electronic bending tools with spring-back compensation.\nManufactures of electrical assembly's produce components that are flat, using copper and aluminum. The mechanical properties of copper and aluminum are very different and require different programmable inputs in order to achieve the same dimensional characteristics. This variation in inputs is due to spring-back compensation.\nBending technology for flat material which measures each bend angle and provides spring back compensation is required. This gives the bend angle of flat materials true accuracy. This is attained by using bending prisms with electronic angular measurement technology. While bending two flat bolds supporting the material turn around. The bolds are directly connected to the angular sensors. A computer or rather the machine control then calculates the required final stroke. The spring back of every bend is compensated regardless of material type.\nIf the measuring accuracy is 0.1º, a high angle accuracy of +/- 0.2º is achieved instantly with the first workpiece without any rework. Because no adjustments are required, material waste amounts and setup times drop considerably. Even inconsistencies within a single piece of material are automatically adjusted.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "11645297", "revid": "46270674", "url": "https://en.wikipedia.org/wiki?curid=11645297", "title": "CR-5000", "text": "CR-5000 is Zuken's EDA design suite for electronics systems and printed circuit boards aimed at the enterprise market. It was developed to tackle complex design needs that involve managing the complete development and manufacturing preparation process on an enterprise-wide scale. CR-5000 offers relevant functionality for the design of complex and high-speed boards, addressing design challenges such as signal integrity and electromagnetic compatibility.\nCR-5000 is the fourth generation successor of CREATE1000 that was originally developed for PDP-11 by Zukei-Gijutsu-Kenkyusho (Japanese for \"Graphic Technology and Research Laboratory\"). The main CR-5000 software is developed at Zuken Inc. headquarters in Yokohama, Japan. Other modules are developed in Zuken's EMC Technology Center in Paderborn, Germany which is renowned for its research in EMC and SI simulation tools, and Zuken Technology Center in Bristol, England which focuses on routing tools. The latest version as of June 2012 is CR-5000 version 14.", "Engineering,_Manufacturing": 1.0000094175, "qwen": "Yes"}
{"id": "946186", "revid": "283288", "url": "https://en.wikipedia.org/wiki?curid=946186", "title": "Menlo Logistics", "text": "Menlo Logistics was a global supply chain company operating in 20 countries on five continents. Its core business offerings included third-party logistics and supply chain management, and the company specialized in the integration of all functions across the supply chain. The company operated 210 locations worldwide and had of warehouse capacity.\nIt was a business unit of Con-way, which was acquired in 2015 by XPO Logistics. Sister companies included Con-way Freight, Con-way Truckload, and Con-way Multimodal.\nHistory.\nThe idea for Menlo Logistics was developed in the late 1980s. At that time, CF Inc.’s director of marketing, John Williford, presented the idea for the company's creation — an organization that offered warehouse, inventory, and transportation management as well as full integration of supply chain links through customized systems and software — to upper management. The initial business plan was to create, implement, and manage logistics projects for its customers.\nOn October 26, 1990, Menlo Logistics Inc. was formed. The name was a deliberate choice to prompt an association with California’s Menlo Park, which was well known as the home of venture capitalists and high-tech industries.\nMenlo Logistics established itself as a third-party logistics provider in the 1990s, and rode the popularity of the outsourcing trend by notching double-digit growth every year during that era. One of Menlo’s early success stories was its successful bid on a $100 million distribution contract with Sears. The department store wanted to close its internal distribution system, which cost Sears about twice as much as its competitors at 7 percent of its sales.\nIn December 2000, Menlo Logistics collaborated with General Motors to create Vector SCM, a new global supply chain management company serving the automotive industry.\nEffective January 1, 2002, Con-Way formed Menlo Worldwide Logistics in its current form by combining Menlo Logistics (renamed Menlo Worldwide Logistics), Vector SCM and Emery Worldwide Forwarding (later renamed Menlo Worldwide Forwarding). Menlo Worldwide Logistics absorbed the operations of Emery’s logistics unit, Emery Global Logistics (EGL). The EGL operations gave Menlo Worldwide Logistics presence in Asia and South America, and expanded its European scope. The company began leveraging these operations to pursue organic growth outside of North America and grow its European footprint.\nIn December 2004, Con-Way sold Menlo Worldwide Forwarding to United Parcel Service, and Con-Way streamlined its operating units by merging Con-Way Transportation Service’s logistics unit, Con-way Logistics, into Menlo Worldwide Logistics. This completed the rationalization of three logistics entities into a single business unit.\nIn 2006, GM exercised its right to purchase Menlo Logistics' interest in Vector SCM, and the sale was completed in December.\nIn seeking to grow its business in the Asian logistics market, Menlo purchased two Asian logistics companies, Cougar Holdings Pte, Ltd. and Chic Holdings, Ltd. in 2007. Singapore-based Cougar enlarged Menlo's operational scope in southeastern Asia, and Shanghai-based Chic significantly expanded Menlo's presence in China.\nIn October 2015 Menlo Logistics and its parent Con-Way were acquired by XPO Logistics.", "Engineering,_Manufacturing": 0.999796927, "qwen": "Yes"}
{"id": "56350120", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=56350120", "title": "Build-on-demand", "text": "Build-on-demand or manufacturing on demand (MOD) refers to a manufacturing process where goods are produced only when or as they are required. This allows scalability and adjustable assemblies depending on the current needs of the part requestor or client.\nManufacturing on demand has the potential to markedly affect the manufacturing industry by shortening lead times and reducing costs. Manufacturing previously relied on Request for quotes (RfQs) that were not digitally obtainable.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "20938512", "revid": "860622609", "url": "https://en.wikipedia.org/wiki?curid=20938512", "title": "Mass finishing", "text": "Mass finishing is a group of manufacturing processes that allow large quantities of parts to be simultaneously finished. The goal of this type of finishing is to burnish, deburr, clean, radius, de-flash, descale, remove rust, polish, brighten, surface harden, prepare parts for further finishing, or break off die cast runners. The two main types of mass finishing are tumble finishing, also known as barrel finishing, and vibratory finishing. Both involve the use of a cyclical action to create grinding contact between surfaces. Sometimes the workpieces are finished against each other; however, usually a finishing medium is used. Mass finishing can be performed dry or wet; wet processes have liquid lubricants, cleaners, or abrasives, while dry processes do not. Cycle times can be as short as 10 minutes for nonferrous workpieces or as long as 2 hours for hardened steel.\nMass finishing processes can be configured as either batch systems, in which batches of workpieces are added, run, and removed before the next batch is run, or as continuous systems, in which the workpieces enter at one end and leave at the other end in the finished state. They may also be sequenced, which involves running the workpieces through multiple different mass finishing processes; usually, the finish becomes progressively finer. Due to the random action of the processes, mass finishing is as much an art as it is a science.\nMedia.\nFunctions of Media.\nMedia are designed for four things:\nCompounds.\nCompounds are added to mass finishing processes to assist in deburring, burnishing, cutting, cleaning, descaling, and inhibiting corrosion. They may be liquids or dry powders. They are usually broken up into four types: deburring and finishing, burnishing, cleaning, and water stabilizing.\nReferences.\nNotes.\n\"Mass Finishing Handbook\" by LaRoux Gillespie, Society of Manufacturing Engineers, 2007", "Engineering,_Manufacturing": 1.0000069141, "qwen": "Yes"}
{"id": "18248544", "revid": "1168278624", "url": "https://en.wikipedia.org/wiki?curid=18248544", "title": "Lean Six Sigma", "text": "Lean Six Sigma is a process improvement approach that uses a collaborative team effort to improve performance by systematically removing operational waste and reducing process variation. It combines Lean Management and Six Sigma to increase the velocity of value creation in business processes.\nHistory.\n1980s–2000s.\nLean Six Sigma's predecessor, Six Sigma, originated from the Motorola company in the United States in 1986. Six Sigma was developed within Motorola to compete with the \"kaizen\" (or lean manufacturing) business model in Japan.\nIn the 1990s, Allied Signal hired Larry Bossidy and introduced Six Sigma in heavy manufacturing. A few years later, General Electric's Jack Welch consulted Bossidy and implemented Six Sigma at the conglomerate. \nDuring the 2000s, Lean Six Sigma forked from Six Sigma and became its own unique process. While Lean Six Sigma developed as a specific process of Six Sigma, it also incorporates ideas from lean manufacturing, which was developed as a part of the Toyota Production System in the 1950s.\n2000s–2010s.\nThe first concept of Lean Six Sigma was created in Chuck Mills, Barbara Wheat, and Mike Carnell's 2001 book, \"Leaning into Six Sigma: The Path to Integration of Lean Enterprise and Six Sigma\". It was developed as a guide for managers of manufacturing plants on how to combine lean manufacturing and Six Sigma to improve quality and cycle time in the plant.\nIn the early 2000s Six Sigma principles expanded into other sectors of the economy, such as healthcare, finance, and supply chains.\nDescription.\nLean Six Sigma is a synergized managerial concept of Lean and Six Sigma. Lean traditionally focuses on eliminating the eight kinds of waste (\"\"muda\")\", and Six Sigma focuses on improving process output quality by identifying and removing the causes of defects (errors) and minimizing variability in (manufacturing and business) processes.\nLean Six Sigma uses the \"Define, Measure, Analyze, Improve and Control (DMAIC)\" phases similar to that of Six Sigma. The five phases used in Lean Six Sigma aim to identify the root cause of inefficiencies and work with any process, product, or service that has a large amount of data or measurable characteristics available.\nThe different levels of certifications are divided into belt colors. The highest level of certification is a black belt, signifying a deep knowledge of Lean Six Sigma principles. Below the black belt are the green and yellow belts. For each of these belts, level skill sets that describe which of the overall Lean Six Sigma tools are expected to be part at a certain belt level are available. The skill sets reflect elements from Six Sigma, Lean and other process improvement methods like the theory of constraints and total productive maintenance. In order to achieve any of the certification levels, a proctored exam must be passed that asks questions about Lean Six Sigma and its applications.\nWaste.\nWaste (\"muda\") is defined by Fujio Cho as \"anything other than the minimum amount of equipment, materials, parts, space, and workers time, which are absolutely essential to add value to the product\".\nDifferent types of waste have been defined in the form of a mnemonic of \"downtime\":", "Engineering,_Manufacturing": 0.9999873638, "qwen": "Yes"}
{"id": "5850600", "revid": "294108", "url": "https://en.wikipedia.org/wiki?curid=5850600", "title": "Pneumatic valve springs", "text": "Pneumatic valve springs are metal bellows filled with compressed air used as an alternative to the metal wire springs used to close valves in high-speed internal combustion engines. This system was introduced in Formula One in 1986 with the Renault EF-Type.\nConcept.\nRacing engines often fail at high rotational speeds because mechanical springs are unable to retract the valves quickly enough to provide clearance for the piston. Renault's pneumatic valve technology replaced steel springs with light weight compressed air bellows. These could retract valves more quickly and reduce the possibility of piston-valve interference, as long as pressure could be maintained. Additionally, the amount of seat tension required to keep a coil sprung valve under control results in greater peak lift loading. This results in added stress to the entire valvetrain. Pneumatic systems, sharing a common reservoir of pressure retain a more static level of force, controlling the valve effectively, without any attendant peak lift load increase.\nThe actuation mechanism is simply a piston and cylinder, similar to a small pneumatic ram. The \"tappet bore\" where a hydraulic tappet would normally reside, becomes the cylinder, and the retainer assembly becomes the piston. Pressurized air (nitrogen) is pumped into this cylinder which then causes the piston/retainer to rise to the top of cylinder, causing the valve to form an airtight seal with the seat. The compressed gas then becomes the spring, so to speak, but does not have the same traits as springs do at elevated rpm. A small light spring is sometimes fitted between the piston and retainer so that when the system is switched off the spring forces the piston down against the bottom of the bore, thus forcing the retainer upwards. This ensures that no crown-to-valve contact occurs when shut down.\nPneumatic valve technology in racing.\nPneumatic valve springs gave Renault an advantage with its turbocharged engines, often said to be one of the most powerful. However, reliability and poor handling of their chassis kept the cars from success until 1989, when Renault provided Williams with a new V10 engine that began a winning streak. \nPneumatic valve springs are also found in several Moto GP motorcycle engines, debuting in 2002 with the Aprilia RS Cube. In 2005, Team Roberts was the first to use pneumatic valves full-time in their uncompetitive KTM powered bike. Today, almost all of the MotoGP teams use pneumatic valve technology on their bikes, including Yamaha, Suzuki and Honda. Ducati uses a desmodromic design.\nFuture valve technology.\nWhile pneumatic valve springs have become standard in Formula One engines, a number of manufacturers have been researching computer-controlled electromagnetic valve actuation (EVA) using no camshaft, to reduce moving parts while improving valve control. In particular, Renault and Freevalve (under supervision of Koenigsegg) are two companies interested in developing the technology for production road vehicles.", "Engineering,_Manufacturing": 1.0000071526, "qwen": "Yes"}
{"id": "5854674", "revid": "38627444", "url": "https://en.wikipedia.org/wiki?curid=5854674", "title": "Tool wear", "text": "In machining, tool wear is the gradual failure of cutting tools due to regular operation. Tools affected include tipped tools, tool bits, and drill bits that are used with machine tools.\nTypes of wear include:\nEffects of tool wear.\nSome general effects of tool wear include:\nReduction in tool wear can be accomplished by using lubricants and coolants while machining. These reduce friction and temperature, thus reducing the tool wear.\nA more general form of the equation is\nwhere\nTemperature considerations.\nAt high temperature zones crater wear occurs.\nThe highest temperature of the tool can exceed 700 °C and occurs at the rake face whereas the lowest temperature can be 500 °C or lower depending on the tool...\nEnergy considerations.\nEnergy comes in the form of heat from tool friction. It is a reasonable assumption that 80% of energy from cutting is carried away in the chip. If not for this the workpiece and the tool would be much hotter than what is experienced. The tool and the workpiece each carry approximately 10% of the energy. The percent of energy carried away in the chip increases as the speed of the cutting operation increases. This somewhat offsets the tool wear from increased cutting speeds. In fact, if not for the energy taken away in the chip increasing as cutting speed is increased; the tool would wear more quickly than is found.\nMulti-criteria of machining operation.\nMalakooti and Deviprasad (1989) introduced the multi-criteria metal cutting problem where the criteria could be cost per part, production time per part, and quality of surface. Also, Malakooti et al. (1990) proposed a method to rank the materials in terms of machinability. Malakooti (2013) presents a comprehensive discussion about tool life and its multi-criteria problem. As an example objectives can be minimizing of Total cost (which can be measured by the total cost of replacing all tools during a production period), maximizing of Productivity (which can be measured by the total number of parts produced per period), and maximizing of quality of cutting.", "Engineering,_Manufacturing": 0.9999289513, "qwen": "Yes"}
{"id": "22633471", "revid": "12416903", "url": "https://en.wikipedia.org/wiki?curid=22633471", "title": "Gashing", "text": "Gashing is a machining process used to rough out coarse pitched gears and sprockets. It is commonly used on worm wheels before hobbing, but also used on internal and external spur gears, bevel gears, helical gears, and gear racks. The process is performed on \"gashers\" or universal milling machines, especially in the case of worm wheels. After gashing the gear or sprocket is finished via hobbing, shaping, or shaving.\nEquipment.\n\"Gashers\" are large, heavy-duty machine tools. They have horizontal and vertical slideways, precise indexing, large diameter ballscrews, and spindle drive motors up to . They are usually controlled via computer numerical control (CNC) or a microprocessor. While they are usually used for rough cutting, they are also sometimes used for finishing. For example, gashers are used for the production of large roller-chain sprockets.\nProcess.\nGashing was first used to rough out worm wheels using a universal milling machine, but then dedicated gashers were built to rough out other types of gears. Because the processes is carried out on two different machines the process differs.\nUniversal milling machine.\nThe process uses a milling cutter with a cross-section that is slightly smaller than the final cross-section of the cut; it has the same diameter as the worm. The cutter is then angled to the \"gashing angle\". The gashing angle is calculated from the lead and pitch diameter of the worm; often tables are available with the gashing angles for common diameters and leads. The cutter is centered over the blank and then plunged into it to the proper depth. The cutter is finally withdrawn and the blank indexed to the next tooth space and cut. This is repeated until all of the tooth spaces have been cut.\nNote that a standard endmill with rounded corners can be used instead if a special milling cutter is unavailable. The endmill should be the pitch diameter.\nNote that is process cannot be used on a small worm wheel that mate with a multiple threaded worm.\nGasher.\nThe process is similar to that outlined for the universal milling machine except a gashing angle is not used. When gashing spur gears, racks, or bevel gears the cutter is plunged into the workpiece and then moved linearly in the proper direction. If a helical gear is being roughed out, then the table rotates and moves along the vertical axis to interpolate the helical path.\nThe two most common cutting tools are formed milling cutters and cutters with indexable carbide inserts. For very large gears a cutter might be replaced with two slitting cutters that cut triangular slugs from the blank.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "8017558", "revid": "42522270", "url": "https://en.wikipedia.org/wiki?curid=8017558", "title": "Continuous-flow manufacturing", "text": "Continuous-flow manufacturing, or repetitive-flow manufacturing, is an approach to discrete manufacturing that contrasts with batch production. It is associated with a just-in-time and kanban production approach, and calls for an ongoing examination and improvement efforts which ultimately requires integration of all elements of the production system. The goal is an optimally balanced production line with little waste, the lowest possible cost, on-time and defect-free production.\nThis strategy is typically applied in discrete manufacturing as an attempt to handle production volumes comprising discrete units of product in a flow which is more naturally found in process manufacturing. The basic fact is that in most cases, discrete units of a solid product cannot be handled in the same way as continuous quantities of liquid, gas or powder.\nDiscrete manufacturing is more likely to be performed in batches of product units that are routed from process to process in the factory. Each process may add value to the batch during a run-time or work-time. There is usually some time spent waiting for the process during a queue-time or wait-time. The larger the batch, the longer each unit has to wait for the rest of the batch to be completed, before it can go forward to the next process. This queue-time is waste, \"Muda\", and represents time lost that is not value-added in the eyes of the customer. This waste is one of the most important elements targeted for reduction and elimination in lean manufacturing.\nReducing the batch size in discrete manufacturing is therefore a desirable goal: it improves the speed of response to the customer, whilst improving the ratio of value-added to non value-added work. However, it should be balanced against the finite capacity of resources at the value-adding processes. Capacity is consumed by changeover whenever a process is required to perform work on a different part or product model than the preceding one. Time consumed in changeover is also considered waste, and it reduces the amount of resource capacity that is available to perform value-adding work. Reducing batch sizes can also increase handling time, risk and complexity in planning and controlling production.\nThe paradigm aim is to achieve single-piece flow where a single discrete unit of product flows from process to process. In effect, the batch quantity is one. If there is no change in part or product model, then this objective needs to be balanced against the additional handling time, and the work-centres that perform the process will typically have to be arranged in close proximity to one another in a flow-line. This is often a characteristic of Repetitive-flow manufacturing and most manual assembly work is performed this way in the modern factory.\nIf there is a change in part or product model, then the process engineer should also consider to balance the changeover time with run-time. If the changeover time is long, as it might be on a machine, batch size reduction is typically preceded with setup reduction techniques such as Single-Minute Exchange of Die.\nOne methodology for Repetitive-flow manufacturing is Demand Flow Technology which combines the principles of Repetitive-flow and demand-driven manufacturing. The production planning and control is linked to a pull signal that is triggered from a customer order or consumption of finished goods stock. A pull signal can also link a process to the down-stream, and synchronize the flow to the demand of the customer.", "Engineering,_Manufacturing": 1.0000095367, "qwen": "Yes"}
{"id": "8028803", "revid": "18872885", "url": "https://en.wikipedia.org/wiki?curid=8028803", "title": "Pattern (casting)", "text": "In casting, a pattern is a replica of the object to be cast, used to prepare the cavity into which molten material will be poured during the casting process.\nPatterns used in sand casting may be made of wood, metal, plastics or other materials. Patterns are made to exacting standards of construction, so that they can last for a reasonable length of time, according to the quality grade of the pattern being built, and so that they will repeatably provide a dimensionally acceptable casting.\nPatternmaking.\nThe making of patterns, called patternmaking (sometimes styled pattern-making or pattern making), is a skilled trade that is related to the trades of tool and die making and moldmaking, but also often incorporates elements of fine woodworking. Patternmakers (sometimes styled pattern-makers or pattern makers) learn their skills through apprenticeships and trade schools over many years of experience. Although an engineer may help to design the pattern, it is usually a patternmaker who executes the design.\nMaterials used.\nTypically, materials used for pattern making are wood, metal or plastics. Wax and Plaster of Paris are also used, but only for specialized applications. Sugar pine wood is the most commonly used material for patterns, primarily because it is soft, light, and easy to work. Honduras mahogany was used for more production parts because it is harder and would last longer than pine. Once properly cured, it is about as stable as any wood available, not subject to warping or curling. Once the pattern is built, the foundry does not want it changing shape. True Honduras mahogany is harder to find now because of the decimation of the rain forests, so now there is a variety of woods marketed as mahogany. Fiberglass and plastic patterns have gained popularity in recent years because they are water proof and very durable. Metal patterns are long lasting and do not succumb to moisture, but they are heavier, more expensive and difficult to repair once damaged.\nWax patterns are used in a casting process called investment casting. A combination of paraffin wax, bees wax and carnauba wax is used for this purpose.\nPlaster of Paris is usually used in making master dies and molds, as it gains hardness quickly, with a lot of flexibility when in the setting stage.\nDesign.\nSprues, gates, risers, cores, and chills.\nThe patternmaker or foundry engineer decides where the \"sprues\", \"gating\" systems, and \"risers\" are placed with respect to the pattern. Where a hole is desired in a casting, a \"core\" may be used which defines a volume or location in a casting where metal will not flow into. Sometimes \"chills\" may be placed on a pattern surface prior to molding, which are then formed into the sand mould. Chills are heat sinks which enable localized rapid cooling. The rapid cooling may be desired to refine the grain structure or determine the freezing sequence of the molten metal which is poured into the mould. Because they are at a much cooler temperature, and often a different metal from what is being poured, they do not attach to the casting when the casting cools. The chills can then be reclaimed and reused.\nThe design of the feeding and gating system is usually referred to as \"methoding\" or \"methods design\". It can be carried out manually, or interactively using general-purpose CAD software, or semi-automatically using special-purpose software (such as AutoCAST)\nTypes of Patterns.\nPatterns are made of wood, metal, ceramic, or hard plastics and vary in complexity.\nA single piece pattern, or loose pattern, is the simplest. It is a replica of the desired casting—usually in a slightly larger size to offset the contraction of the intended metal. Gated patterns connect a number of loose patterns together with a series of runners that will be detached after shake-out. Segmented or multi-piece patterns create a casting in several pieces to be joined in post-processing.\nMatch plate patterns are patterns with the top and bottom parts of the pattern, also known as the cope and drag portions, mounted on opposite sides of a board. This adaptation allows patterns to be quickly moulded out of the molding material. A similar technique called a cope and drag pattern is often used for large castings or large production runs: in this variation, the two sides of the pattern are mounted on separate pattern plates that can be hooked up to horizontal or vertical machines and moulded with the molding material. When the parting lines between the cope and drag are irregular, a follow board can be used to support irregularly shaped, loose patterns.\nSweep patterns are used for symmetric molds, which are contoured shapes rotated around a center axis or pole through the molding material. A sweep pattern is a form of skeleton pattern: any geometrical pattern that creates a mold by being moved through the molding material.\nSkeleton pattern comes into play when the entire setup made of wood or metal is costlier. It is made usually as a part with some gaps left unfilled and those unfilled parts are filled or covered by loam sand or clays. Strickle board or Strike-off board is used to scrape the excess clay if applied to the gaps.\nE.g. Turbine Casing, Soil and Water pipe bends, valve bodies and boxes.\nAllowances.\nTo compensate for any dimensional changes which will happen during the (solid) cooling process, allowances are usually made in the pattern.\nLiquid Shrinkage.\nAlmost all metals shrink volumetrically during solidification, this is known as liquid shrinkage.\nAnother way of saying that is almost all metals undergo a volume increase upon melting, or liquidus temperature.\nTypical \"volume shrinkage\" is in the range between 3.5% to 10.0% depending on the alloy.\nSome graphitic cast irons, when cast in heavier sections, under well controlled conditions, can exhibit a slight positive yield.\nType Metal is also known, and used, for its ability to hold a true and sharp cast, and retain correct dimensions after cooling.\nNormally when making engineering cast parts the \"method\" is designed along with the pattern - being the riser size, number of risers, and location of risers. Additionally downsprue(s), runner bar(s), and ingate(s) are also designed in \"the method\". The \"method\" thus ensures the molten metal is delivered, the mould filled correctly, and the risers filled to \"feed\" the \"shrinking volume\" of liquid to the casting during solidification. This \"method\" is done by a \"methods engineer\", who may be a patternmaker (with additional training), a founding engineer, or metallurgist who is familiar with concept of volume increase / volume loss associated with melting and casting / solidification. Example: Assume steel at 7.85 density (solid) and 6% shrinkage, or better said, a 6% volume increase when molten. A mould has been made to cast a 100 kg block, based on the solid density of steel. The liquid density of steel is only 94% that of its solid density value - about 7.38 when liquid. Thus when the 100 kg block (solid calculation) is filled with liquid it contains a mass of only 94 kg. The 6 kg, has to be supplied from a \"riser\" or \"feeder\" during solidification - thus the solid object now has a mass of 100 kg.\nThe method is a system to deal with the volume loss during solidification. This (technically) is not an allowance.\nThis extra size that is given on the pattern for metal contraction is called \"the contraction allowance\".\nThese values are typically between 0.6% and 2.5%.\nThis is accounted for using a contraction rule, which is an oversized rule. Contraction rules are generally available for the common industrially cast alloys. Alternately, the Patternmaker will simply add a nominated percentage to all dimensions.\nAn example of this allowance - if a bush were required to be 1500mm O/D, 1000mm I/D and 300mm high using a 2% contraction rule: The Patternmaker would make the pattern 1530mm O/D, (as it will contract in), 1020 I/D (as material tend to contract towards the Centre or Centre of gravity ) - important to note that allowance is added even to the inside diameter as material tend to contact towards the Centre. The core used is either made up of collapsible sand or it is given enough hollow space at the centre of the core to allow metal to expand. Finally, the height dimension would be 306mm.\nThe contraction amount can also be varied slightly by the sand system being used for the mould and any cores, for example clay-bonded sand, chemical bonded sands, or other bonding materials used within the sand. Exact values can vary between different foundries due to the sand systems being used. Each foundry, by gauging its own patterns and castings, can refine its own contraction allowances.\nShrinkage and Contraction can again be classified into \"liquid shrinkage\" and \"solid contraction\".\nLiquid shrinkage is the reduction in volume during the process of solidification (liquid to solid), the liquid shrinkage is accounted for by risers.\nSolid contraction is the reduction in dimensions during the cooling of the (solid) cast metal. Contraction allowance takes into account only the solid contraction.\nDraft allowance.\nWhen the pattern is to be removed from the sand mold, there is a possibility that any leading edges may break off, or get damaged in the process. To avoid this, a taper is provided on the pattern, so as to facilitate easy removal of the pattern from the mold, and hence reduce damage to edges. The taper angle provided is called the \"Draft angle\". The value of the draft angle depends upon the complexity of the pattern, the type of molding (hand molding or machine molding), height of the surface, etc. Draft provided on the casting is usually 1 to 3 degrees on external surfaces (5 to 8 internal surfaces).\nFinishing or Machining allowance.\nThe surface finish obtained in sand castings is generally poor (dimensionally inaccurate), and hence in many cases, the cast product is subjected to machining processes like turning or grinding in order to improve the surface finish. During machining processes, some metal is removed from the piece. To compensate for this, a machining allowance (additional material some times referred to as green) should be given in the casting. the amount of finish allowance depends on the material of the casting, size of casting, volume of production, method of molding, etc.\nShake allowance.\nUsually during removal of the pattern from the mold cavity, the pattern is rapped all around the faces, in order to facilitate easy removal. In this process, the final cavity is enlarged. To compensate for this, the pattern dimensions need to be reduced. There are no standard values for this allowance, as it is heavily dependent on the personnel. This allowance is a negative allowance, and a common way of going around this allowance is to increase the draft allowance. Shaking of the pattern causes an enlargement of the mould cavity and results in a bigger casting.\nDistortion allowance.\nDuring cooling of the mould, stresses developed in the solid metal may induce distortions in the cast. This is more evident when the mould is thinner in width as compared to its length. This can be eliminated by initially distorting the pattern in the opposite direction.\nDemand.\nPatterns continue to be needed for sand casting of metals. For the production of gray iron, ductile iron and steel castings, sand casting remains the most widely used process. For aluminum castings, sand casting represents about 12% of the total tonnage by weight (surpassed only by die casting at 57%, and semi-permanent and permanent mold at 19%; based on 2006 shipments). The exact process and pattern equipment is always determined by the order quantities and the casting design. Sand casting can produce as little as one part, or as many as a million copies.\nAlthough additive manufacturing modalities such as SLS or SLM have potential to replace casting for some production situations, casting is still far from being completely displaced. Wherever it provides suitable material properties at competitive unit cost, it will remain in demand.", "Engineering,_Manufacturing": 0.9971362948, "qwen": "Yes"}
{"id": "2618828", "revid": "1272505", "url": "https://en.wikipedia.org/wiki?curid=2618828", "title": "Rotary table", "text": "A rotary table is a precision work positioning device used in metalworking. It enables the operator to drill or cut work at exact intervals around a fixed (usually horizontal or vertical) axis. Some rotary tables allow the use of index plates for indexing operations, and some can also be fitted with dividing plates that enable regular work positioning at divisions for which indexing plates are not available. A rotary fixture used in this fashion is more appropriately called a dividing head (indexing head).\nConstruction.\nThe table shown is a manually operated type. Powered tables under the control of CNC machines are now available, and provide a fourth axis to CNC milling machines. Rotary tables are made with a solid base, which has provision for clamping onto another table or fixture. The actual table is a precision-machined disc to which the work piece is clamped (T slots are generally provided for this purpose). This disc can rotate freely, for indexing, or under the control of a worm (handwheel), with the worm wheel portion being made part of the actual table. High precision tables are driven by backlash compensating duplex worms.\nThe ratio between worm and table is generally 40:1, 72:1 or 90:1 but may be any ratio that can be easily divided exactly into 360°. This is for ease of use when indexing plates are available. A graduated dial and, often, a vernier scale enable the operator to position the table, and thus the work affixed to it with great accuracy.\nA through hole is usually machined into the table. Most commonly, this hole is machined to admit a Morse taper center or fixture.\nUse.\nRotary tables are most commonly mounted \"flat\", with the table rotating around a vertical axis, in the same plane as the cutter of a vertical milling machine. An alternate setup is to mount the rotary table on its end (or mount it \"flat\" on a 90° angle plate), so that it rotates about a horizontal axis. In this configuration a tailstock can also be used, thus holding the workpiece \"between centers.\"\nWith the table mounted on a secondary table, the workpiece is accurately centered on the rotary table's axis, which in turn is centered on the cutting tool's axis. All three axes are thus coaxial. From this point, the secondary table can be offset in either the X or Y direction to set the cutter the desired distance from the workpiece's center. This allows concentric machining operations on the workpiece. Placing the workpiece eccentrically a set distance from the center permits more complex curves to be cut. As with other setups on a vertical mill, the milling operation can be either drilling a series of concentric, and possibly equidistant holes, or face or end milling either circular or semicircular shapes and contours.\nA rotary table can be used:\nAdditionally, if converted to stepper motor operation, with a CNC milling machine and a tailstock, a rotary table allows many parts to be made on a mill that otherwise would require a lathe.\nApplications.\nRotary tables have many applications, including being used in the manufacture and inspection process of important elements in aerospace, automation and scientific industries. The use of rotary tables stretches as far as the film and animation industry, being used to obtain accuracy and precision in filming and photography. ", "Engineering,_Manufacturing": 1.0000085831, "qwen": "Yes"}
{"id": "2619011", "revid": "1161691550", "url": "https://en.wikipedia.org/wiki?curid=2619011", "title": "Coordinate-measuring machine", "text": "A coordinate measuring machine (CMM) is a device that measures the geometry of physical objects by sensing discrete points on the surface of the object with a probe. Various types of probes are used in CMMs, the most common being mechanical and laser sensors, though optical and white light sensor do exist. Depending on the machine, the probe position may be manually controlled by an operator or it may be computer controlled. CMMs typically specify a probe's position in terms of its displacement from a reference position in a three-dimensional Cartesian coordinate system (i.e., with XYZ axes). In addition to moving the probe along the X, Y, and Z axes, many machines also allow the probe angle to be controlled to allow measurement of surfaces that would otherwise be unreachable.\nDescription.\nThe typical 3D \"bridge\" CMM allows probe movement along three axes, X, Y and Z, which are orthogonal to each other in a three-dimensional Cartesian coordinate system. Each axis has a sensor that monitors the position of the probe on that axis, with typical accuracy in the order of microns. When the probe contacts (or otherwise detects) a particular location on the object, the machine samples the axis position sensors, thus measuring the location of one point on the object's surface, as well as the 3-dimensional vector of the measurement taken. This process is repeated as necessary, moving the probe each time, to produce a \"point cloud\" which describes the surface areas of interest. The points can be measured either manually by an operator or automatically via Direct Computer Control (DCC) or automatically using scripted programs; thus, an automated CMM is a specialized form of industrial robot.\nA common use of CMMs is in manufacturing and assembly processes to test a part or assembly against the design intent. The measured points can be used to verify the distance between features. They can also be used to construct geometric features such as cylinders and planes etc. for GD&T such as roundness, flatness and perpendicularity can be assessed.\nTechnical facts.\nParts.\nCoordinate-measuring machines include three main components:\nAvailability.\nThese machines are available as stationary or portable.\nAccuracy.\nThe accuracy of coordinate measurement machines are typically given as an uncertainty factor as a function over distance. For a CMM using a touch probe, this relates to the repeatability of the probe and the accuracy of the linear scales. Typical probe repeatability can result in measurements of within .001mm or .00005 inch (half a ten thousandth) over the entire measurement volume. For 3, 3+2, and 5 axis machines, probes are routinely calibrated using traceable standards and the machine movement is verified using gauges to ensure accuracy.\nSpecific parts.\nMachine body.\nThe first CMM was developed by the Ferranti Company of Scotland in the 1950s as the result of a direct need to measure precision components in their military products, although this machine only had 2 axes. The first 3-axis models began appearing in the 1960s (DEA of Italy / LK of the UK) and computer control debuted in the early 1970s but the first working CMM was developed and put on sale by Browne & Sharpe in Melbourne, England. (Leitz Germany subsequently produced a fixed machine structure with moving table.\nIn modern machines, the gantry-type superstructure has two legs and is often called a bridge. This moves freely along the granite table with one leg (often referred to as the inside leg) following a guide rail attached to one side of the granite table. The opposite leg (often outside leg) simply rests on the granite table following the vertical surface contour. Air bearings are the chosen method for ensuring friction free travel. In these, compressed air is forced through a series of very small holes in a flat bearing surface to provide a smooth but controlled air cushion on which the CMM can move in a near frictionless manner which can be compensated for through software. The movement of the bridge or gantry along the granite table forms one axis of the XY plane. The bridge of the gantry contains a carriage which traverses between the inside and outside legs and forms the other X or Y horizontal axis. The third axis of movement (Z axis) is provided by the addition of a vertical quill or spindle which moves up and down through the center of the carriage. The touch probe forms the sensing device on the end of the quill. The movement of the X, Y and Z axes fully describes the measuring envelope. Optional rotary tables can be used to enhance the approachability of the measuring probe to complicated workpieces. The rotary table as a fourth drive axis does not enhance the measuring dimensions, which remain 3D, but it does provide a degree of flexibility. Some touch probes are themselves powered rotary devices with the probe tip able to swivel vertically through more than 180 degrees and through a full 360 degree rotation.\nCMMs are now also available in a variety of other forms. These include CMM arms that use angular measurements taken at the joints of the arm to calculate the position of the stylus tip, and can be outfitted with probes for laser scanning and optical imaging. Such arm CMMs are often used where their portability is an advantage over traditional fixed bed CMMs- by storing measured locations, programming software also allows moving the measuring arm itself, and its measurement volume, around the part to be measured during a measurement routine. Because CMM arms imitate the flexibility of a human arm they are also often able to reach the insides of complex parts that could not be probed using a standard three axis machine.\nMechanical probe.\nIn the early days of coordinate measurement (CMM), mechanical probes were fitted into a special holder on the end of the quill. A very common probe was made by soldering a hard ball to the end of a shaft. This was ideal for measuring a whole range of flat face, cylindrical or spherical surfaces. Other probes were ground to specific shapes, for example a quadrant, to enable measurement of special features. These probes were physically held against the workpiece with the position in space being read from a 3-axis digital readout (DRO) or, in more advanced systems, being logged into a computer by means of a footswitch or similar device. Measurements taken by this contact method were often unreliable as machines were moved by hand and each machine operator applied different amounts of pressure on the probe or adopted differing techniques for the measurement.\nA further development was the addition of motors for driving each axis. Operators no longer had to physically touch the machine but could drive each axis using a handbox with joysticks in much the same way as with modern remote controlled cars. Measurement accuracy and precision improved dramatically with the invention of the electronic touch trigger probe. The pioneer of this new probe device was David McMurtry who subsequently formed what is now Renishaw plc. Although still a contact device, the probe had a spring-loaded steel ball (later ruby ball) stylus. As the probe touched the surface of the component the stylus deflected and simultaneously sent the X,Y,Z coordinate information to the computer. Measurement errors caused by individual operators became fewer and the stage was set for the introduction of CNC operations and the coming of age of CMMs.\nOptical probes are lens-CCD-systems, which are moved like the mechanical ones, and are aimed at the point of interest, instead of touching the material. The captured image of the surface will be enclosed in the borders of a measuring window, until the residue is adequate to contrast between black and white zones. The dividing curve can be calculated to a point, which is the wanted measuring point in space. The horizontal information on the CCD is 2D (XY) and the vertical position is the position of the complete probing system on the stand Z-drive (or other device component).\nScanning probe systems.\nThere are newer models that have probes that drag along the surface of the part taking points at specified intervals, known as scanning probes. This method of CMM inspection is often more accurate than the conventional touch-probe method and most times faster as well.\nThe next generation of scanning, known as noncontact scanning, which includes high speed laser single point triangulation, laser line scanning, and white light scanning, is advancing very quickly. This method uses either laser beams or white light that are projected against the surface of the part. Many thousands of points can then be taken and used not only to check size and position, but to create a 3D image of the part as well. This \"point-cloud data\" can then be transferred to CAD software to create a working 3D model of the part. These optical scanners are often used on soft or delicate parts or to facilitate reverse engineering.\nProbing systems for microscale metrology applications are another emerging area. There are several commercially available coordinate measuring machines (CMM) that have a microprobe integrated into the system, several specialty systems at government laboratories, and any number of university-built metrology platforms for microscale metrology. Although these machines are good and in many cases excellent metrology platforms with nanometric scales, their primary limitation is a reliable, robust, capable micro/nano probe. Challenges for microscale probing technologies include the need for a high aspect ratio probe giving the ability to access deep, narrow features with low contact forces so as to not damage the surface and high precision (nanometer level). Additionally microscale probes are susceptible to environmental conditions such as humidity and surface interactions such as stiction (caused by adhesion, meniscus, and/or Van der Waals forces among others).\nTechnologies to achieve microscale probing include scaled down version of classical CMM probes, optical probes, and a standing wave probe among others. However, current optical technologies cannot be scaled small enough to measure deep, narrow feature, and optical resolution is limited by the wavelength of light. X-ray imaging provides a picture of the feature but no traceable metrology information.\nOptical probes and/or laser probes can be used (if possible in combination), which change CMMs to measuring microscopes or multi-sensor measuring machines. Fringe projection systems, theodolite triangulation systems or laser distant and triangulation systems are not called measuring machines, but the measuring result is the same: a space point. Laser probes are used to detect the distance between the surface and the reference point on the end of the kinematic chain (i.e.: end of the Z-drive component). This can use an interferometrical function, focus variation, light deflection or a beam shadowing principle.\nPortable coordinate-measuring machines.\nWhereas traditional CMMs use a probe that moves on three Cartesian axes to measure an object's physical characteristics, portable CMMs use either articulated arms or, in the case of optical CMMs, arm-free scanning systems that use optical triangulation methods and enable total freedom of movement around the object.\nPortable CMMs with articulated arms have six or seven axes that are equipped with rotary encoders, instead of linear axes. Portable arms are lightweight (typically less than 20 pounds) and can be carried and used nearly anywhere. However, optical CMMs are increasingly being used in the industry. Designed with compact linear or matrix array cameras (like the Microsoft Kinect), optical CMMs are smaller than portable CMMs with arms, feature no wires, and enable users to easily take 3D measurements of all types of objects located almost anywhere.\nCertain nonrepetitive applications such as reverse engineering, rapid prototyping, and large-scale inspection of parts of all sizes are ideally suited for portable CMMs. The benefits of portable CMMs are multifold. Users have the flexibility in taking 3D measurements of all types of parts and in the most remote/difficult locations. They are easy to use and do not require a controlled environment to take accurate measurements. Moreover, portable CMMs tend to cost less than traditional CMMs.\nThe inherent trade-offs of portable CMMs are manual operation (they always require a human to use them). In addition, their overall accuracy can be somewhat less accurate than that of a bridge type CMM and is less suitable for some applications.\nMultisensor-measuring machines.\nTraditional CMM technology using touch probes is today often combined with other measurement technology. This includes laser, video or white light sensors to provide what is known as multisensor measurement.\nStandardization.\nTo verify the performance of a coordinate measurement machine, the ISO 10360 series is available. This series of standards define the characteristics of the probing system and the length measurement error:\nThe ISO 10360 series consists of the following parts:", "Engineering,_Manufacturing": 1.0000044107, "qwen": "Yes"}
{"id": "26861891", "revid": "27823944", "url": "https://en.wikipedia.org/wiki?curid=26861891", "title": "Reproduction auto part", "text": "A reproduction part, or repro, is a part that has been independently manufactured to meet original equipment manufacturer's (OEM) specifications by a third party manufacturer. This is usually done to meet demand for spare parts no longer produced by the manufacturer. While some reproductions may be indistinguishable from the originals, most are close imitations.", "Engineering,_Manufacturing": 0.9998682737, "qwen": "Yes"}
{"id": "26880598", "revid": "1860416", "url": "https://en.wikipedia.org/wiki?curid=26880598", "title": "ITW Mima Packaging Systems", "text": "ITW Mima Packaging Systems is the European marketing division of ITW's Specialty Systems businesses, manufacturing fully automatic stretch wrapping machines in Finland, semi-automatic and automatic machines in Bulgaria and manufacturing film in Belgium and Ireland.\nOverview.\nMima was founded in 1976 in the United States, to manufacture stretch wrapping machinery it was acquired by ITW in 1986. Alongside this, Matti Haloila started his own company in Finland and manufactured HaloilaHaloila - Etusivu semi-automatic stretch wrappers from 1976. In 1983 Haloila launched an automatic, rotating ring stretch wrapper with the brand name Octopus.\nHaloila became part of the Illinois Tool Works (ITW) in 1995, shortly after this, ITW acquired the stretch film business from Mobil and ITW Mima Packaging System was formed. ITW Mima Packaging Systems manufacture stretch films in Belgium and Ireland and stretch wrappers in Bulgaria and Finland.\nIn 2006 Mima launched the Octopus Twin a wrapping machine capable of wrapping 150 pallets per hour. ITW Mima delivered their 3000th Octopus stretch wrapper in 2008.\nThe Octopus is also currently being manufactured for the US market in Canada by ITW Muller.\nOther Haloila’s wrapping machines include the Cobra, Ecomat and Rolle.\nITW Mima Packagings Systems is a member of the Process and Packaging Machinery Association (PPMA)", "Engineering,_Manufacturing": 0.9999700785, "qwen": "Yes"}
{"id": "26883627", "revid": "6150386", "url": "https://en.wikipedia.org/wiki?curid=26883627", "title": "Via fence", "text": "A via fence, also called a picket fence, is a structure used in planar electronic circuit technologies to improve isolation between components which would otherwise be coupled by electromagnetic fields. It consists of a row of via holes which, if spaced close enough together, form a barrier to electromagnetic wave propagation of slab modes in the substrate. Additionally if radiation in the air above the board is also to be suppressed, then a strip pad with via fence allows a shielding can to be electrically attached to the top side, but electrically behave as if it continued through the PCB.\nModern electronics have components and sub-units at high densities to achieve small size. Typically, many functions are integrated on to the same board or die. If these are not properly shielded from each other, many problems can result including poor frequency response, noise performance, and distortion.\nVia fences are used to shield microstrip and stripline transmission lines, guard edges of printed circuit boards, shield functional circuit units from each other, and to form the walls of waveguides integrated into a planar format. Via fences are cheap and easy to implement, but use up board space and are not as effective as solid metal walls.\nPurpose.\nPlanar technologies are used at microwave frequencies and make use of printed circuit tracks as transmission lines. As well as interconnections, these lines can be used to form components of functional units such as filters and couplers. Planar lines readily couple to each other when in close proximity, an effect called parasitic coupling. The coupling is due to fringing fields spreading from the edges of the line and intersecting adjacent lines or components. This is a desirable feature within the unit where it is made use of as part of the design. It is not desirable, however, that the fields couple to adjacent units. Modern electronic devices are usually required to be small. That, and the drive to keep down costs, leads to a high degree of integration and circuit units in less than desirable proximity. Via fences are one method that can be used to reduce parasitic coupling between such units.\nAmongst the many problems that can be caused by parasitic coupling are reducing bandwidth, degrading passband flatness, reducing amplifier output power, increasing reflections, worsening noise figure, causing amplifier instability, and providing undesirable feedback paths.\nIn stripline, via fences running parallel to the line on either side serve to tie together the groundplanes, so preventing the propagation of parallel-plate modes. A similar arrangement is used to suppress unwanted modes in metal-backed coplanar waveguide.\nStructure.\nA via fence consists of a row of via holes, that is, holes that pass through the substrate and are metallised on the inside to connect to pads on the top and bottom of the substrate. In a stripline format both the top and bottom of the dielectric sheet are covered with a metal ground plane so any via holes are automatically grounded at both ends. In other planar formats such as microstrip there is a ground plane only at the bottom of the substrate. In these formats it is the usual practice to connect the top pads of the via fence with a metal track (see figure 2). This still does not completely fence off the field as can be done in stripline. In stripline the field can only propagate between the ground planes, but in microstrip it is able to leak over the top of the via fence. Nevertheless, connecting the top pads improves isolation by . In some technologies it is more convenient to form the fence from conducting posts rather than vias.\nIsolation can be further improved by placing a metal wall on top of the via fence. These walls commonly form part of the device enclosure. The large holes in the via fences seen in figures 1 and 5 are screw holes for clamping these walls in place. The wall casting belonging to this circuit is shown in figure 3.\nThe design of the fence needs to consider the size and spacing of the vias. Ideally, vias should act as short circuits, but they are not ideal and a via equivalent circuit can be modelled as a shunt inductance. Sometimes, a more complex model is required such as the equivalent circuit shown in figure 4. \"L\"1 is due to the inductance of the pads and \"C\" is the capacitance between them. \"R\" and \"L\"2 are, respectively, the resistance and inductance of the via hole metallisation. Resonances must be considered, in particular the parallel resonance of \"C\" and \"L\"2 will allow electromagnetic waves to pass at the resonant frequency. This resonance needs to be placed outside the operating frequencies of the equipment concerned. Spacing of the fences needs to be small in comparison to a wavelength (λ) in the substrate dielectric so as to make the fence appear solid to impinging waves. If too large, waves will be able to pass through the gaps. A common rule of thumb is to make the spacing less than λ/20 at the maximum operating frequency.\nApplications.\nVia fences are used primarily at RF and microwave frequencies wherever planar formats are being applied. They are used in printed circuit technologies such as microstrip, ceramic technologies such as low temperature co-fired ceramic, monolithic microwave integrated circuits, and system-in-a-package technology. They are especially important in isolating circuit units operating at different frequencies.\nAlso called via stitching, via fences can be used around the edge of a printed circuit board, an example can be seen in figure 5. This may be done to prevent electromagnetic interference with other equipment, or even to block radiation re-entering from elsewhere on the same circuit.\nVia fences are also used in post-wall waveguide, also known as laminated waveguide (LWG). In LWG, two parallel via fences form the sidewalls of a waveguide. Between them, and the upper and lower groundplanes of the substrate, is an electromagnetically isolated space. There is no electrical conductor within this space, but electromagnetic waves can exist within the enclosed dielectric material of the substrate and their direction of propagation is guided by the LWG. This technology is typically used at millimetre band frequencies and consequently dimensions are quite small. Furthermore, good isolation requires that the vias are closely spaced. Typically, isolation is required between guides, that is per fence. A typical W band  fence specification meeting this requirement in LWG is vias spaced between centres. This can be challenging to manufacture, and a higher density of vias is sometimes achieved by constructing the fence from two staggered rows of vias.\nAdvantages and disadvantages.\nVia fences are cheap and convenient. When used on planar formats they require no additional processes to manufacture. On a printed circuit for instance, they are made in the same process that creates the track patterns. However, via fences are not able to approach the isolation achievable with unbroken metal walls.\nVia fences use up a lot of valuable substrate real estate and so will increase the overall size of the assembly. Via fences too close to the line being guarded can degrade the isolation otherwise achievable. In stripline, a rule of thumb is to place the fences at least four times the trace to groundplane distance away from the line being guarded.", "Engineering,_Manufacturing": 0.9985589385, "qwen": "Yes"}
{"id": "26893990", "revid": "23914831", "url": "https://en.wikipedia.org/wiki?curid=26893990", "title": "Insertion mount machine", "text": "An insertion mount machine or inserter is a device used to insert the leads of electronic components through holes in printed circuit boards.\nMachine configuration.\nAn insertion mount machine often has a rotary table on a X- and Y-axis positioning system which moves the board to the necessary position for the component's insertion into the board. The machine can be configured to be standalone machine.\nAxial insertion.\nAn axial inserter takes axial leaded through-hole components from reels which are fed into dispensing heads that cut the parts onto a chain in the order of insertion; transferred from the sequence chain to the insertion chain, which brings the component underneath the insertion head which then cuts the leads of the component to the correct length for lead length and insertion span; bends the leads 90°; and inserts the component leads into the board while a clinch assembly underneath cuts and bends the leads towards each other.\nRadial insertion.\nA radial inserter takes radial leaded through-hole components from a reels which are fed into dispensing heads that cut the component from the reel and place it onto the chain in sequence of the order of insertion. The component is brought to a component transfer assembly behind the insertion head and is transferred to the insertion head, then inserted into the board while a clinch assembly underneath cuts and bends the leads opposite to each other.\nDual in-line package insertion.\nA dual in-line (DIP) inserter takes integrated circuits from tubes which are loaded into magazines. A shuttle mechanism picks the needed component needed from the magazines and drops it into a transfer assembly. The insertion head picks the component from the transfer assembly and inserts the IC into the board while a clinch assembly underneath cuts and bends the leads either inward for sockets or outward for ICs.\nDue to the transition from insertion mount technology (through-hole) to surface-mount technology of integrated circuits, these machines are no longer being newly manufactured.\nObsolete configurations.\nAxial inserters used to consist of a stand-alone sequencer machine which cut and sequenced the parts onto a reel. That reel was then transferred over to a standalone axial inserter to insert the components. This is all done on one machine today.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "22875022", "revid": "8766034", "url": "https://en.wikipedia.org/wiki?curid=22875022", "title": "Operating weight", "text": "Operating weight is a measure of the total weight of a vehicle or machine when it is in use, including all necessary components such as the driver or operator, fuel, and any additional equipment or tools required for its operation.", "Engineering,_Manufacturing": 1.0000092983, "qwen": "Yes"}
{"id": "13983624", "revid": "1151636597", "url": "https://en.wikipedia.org/wiki?curid=13983624", "title": "Master production schedule", "text": "A master production schedule (MPS) is a plan for individual commodities to be produced in each time period such as production, staffing, inventory, etc. It is usually linked to manufacturing where the plan indicates when and how much of each product will be demanded. This plan quantifies significant processes, parts, and other resources in order to optimize production, to identify bottlenecks, and to anticipate needs and completed goods. Since a MPS drives much factory activity, its accuracy and viability dramatically affect profitability. Typical MPSs are created by software with user tweaking.\nDue to software limitations, but especially the intense work required by the \"master production schedulers\", schedules do not include every aspect of production, but only key elements that have proven their control effectivity, such as forecast demand, production costs, inventory costs, lead time, working hours, capacity, inventory levels, available storage, and parts supply. The choice of what to model varies among companies and factories. The MPS is a statement of what the company expects to produce and purchase (i.e. quantity to be produced, staffing levels, dates, available to promise, projected balance).\nThe MPS translates the customer demand (sales orders, PIR’s), into a build plan using planned orders in a true component scheduling environment. Using MPS helps avoid shortages, costly expediting, last minute scheduling, and inefficient allocation of resources. Working with MPS allows businesses to consolidate planned parts, produce master schedules and forecasts for any level of the Bill of Material (BOM) for any type of part.\nHow an MPS works.\nBy using many variables as inputs the MPS will generate a set of outputs used for decision making. Inputs may include forecast demand, production costs, inventory money, customer needs, inventory progress, supply, lot size, production lead time, and capacity. Inputs may be automatically generated by an ERP system that links a sales department with a production department. For instance, when the sales department records a sale, the forecast demand may be automatically shifted to meet the new demand. Inputs may also be inputted manually from forecasts that have also been calculated manually. Outputs may include amounts to be produced, staffing levels, quantity available to promise, and projected available balance. Outputs may be used to create a Material Requirements Planning (MRP) schedule.\nA master production schedule may be necessary for organizations to synchronize their operations and become more efficient. An effective MPS ultimately will:\nMPS issues:\nProduction plan.\nAn example of a master production schedule for \"product A\".", "Engineering,_Manufacturing": 0.99995327, "qwen": "Yes"}
{"id": "32921983", "revid": "1061846325", "url": "https://en.wikipedia.org/wiki?curid=32921983", "title": "Lot number", "text": "A lot number is an identification number assigned to a particular quantity or lot of material from a single manufacturer. Lot numbers can typically be found on the outside of packaging. For cars, a lot number is combined with a serial number to form the Vehicle Identification Number.\nThe lot number enables tracing of the constituent parts or ingredients as well as labor and equipment records involved in the manufacturing of a product. This enables manufacturers and other entities to perform quality control checks, calculate expiration dates, and issue corrections or recall information to subsets of their production output. It also gives consumers an identifier that they can use in contacting the manufacturer and researching the production of goods received. For example to trace back the origin of fish or meat, in case of a public health problem.\nSome lot numbers are generated with the use of date and time stamps to help identify a specific lot.", "Engineering,_Manufacturing": 0.9998517036, "qwen": "Yes"}
{"id": "9625683", "revid": "7770027", "url": "https://en.wikipedia.org/wiki?curid=9625683", "title": "Overstock", "text": "Overstock, excessive stock, or excess inventory arise when there is more than the \"right quantity\" of goods available for sale, or when \"the the potential sales value of excess stock, less the expected storage costs, does not match the salvage value\". It arises as a result of poor management of stock demand or of material flow in process management. Excessive stock is also associated with loss of revenue owing to additional capital bound with the purchase or simply storage space taken. Excessive stock can result from over delivery from a supplier or from poor ordering and management of stock by a buyer for the stock. Excess or unnecessary inventory is listed as one of the seven wastes or \"muda\" in Taiichi Ohno's Toyota production system.\nWhen referring to overstock merchandise in the form of consumer goods in a retail operation, the term refers to goods that have never been purchased by a customer but that are considered excessive stock from shelves and/or warehouses. Excessive stock is typically discarded of in the following ways: returned to the manufacturer or original distributor; liquidated to companies that then resell it on the secondary wholesale or retail market; sold at an extreme discount to existing customers; or sold to salvage companies which then process metals and components of value.\nTechniques such as supply chain management and lean manufacturing are intended to avoid the excessive development of inventory.\nEconomic implications.\nThe initial damage caused by excessive stock is an early exhaustion of cash flow, which leads to the subsequent loss of disposable capital available for investing. If a company has too much overstock inventory on its books, it may affect sales to the point where the company has to go out of business. Although this is rare, when overstock inventory is not properly managed and becomes too large a percentage of total inventory, it can result in bankruptcy.\nWith perishable supplies, excessive stock can cause the loss of millions of currency units as the product's freshness may deteriorate to such an extent that it cannot be sold, as is the case with dairy products, fresh baked goods, flowers, produce, fish, and meat. It is also true of consumables such as oil, gasoline, paints, and medications. Time-sensitive items such as periodical literature are similarly at risk.\nSales of excess inventories.\nCrandall and Crandall reported 238,000 responses to a web search for \"excess inventories\" in 2003, with a majority of websites offering to buy or sell \"excess inventories\" in specific sales categories.", "Engineering,_Manufacturing": 0.9929094315, "qwen": "Yes"}
{"id": "47947669", "revid": "931821511", "url": "https://en.wikipedia.org/wiki?curid=47947669", "title": "Machine operator efficiency", "text": "In lean manufacturing, machine operator efficiency (MOE) is the performance of an employee who operates industrial machinery. The operator's efficiency is measured as the time spent producing product divided by the time the operator is on duty. For example: if an operator is assigned to run a CNC machine tool for seven hours, but they only have four hours' worth of continuous uninterrupted output of workpieces—their MOE rating is 57% (4 divided by 7) for this seven-hour period of time.\nThere is a similar lean manufacturing KPI called overall equipment effectiveness (OEE). The major difference between OEE and MOE is that the OEE rating is on the machine and the MOE is on the person.\nMOE is a measure of operator performance only, regardless of the type of machine or the speed of the machine they are working on. MOE only measures the operator's ability to keep the machine running continuously (load and unload parts faster that the automatic cycle time of the machine). The MOE rating of an operator will travel with them as they moves from one machine to another. This is easily accomplished because the MOE rating is a universal calculation of time and not reliant on the complex OEE calculations of loading, availability, performance, and quality.\nIndustrial dashboards can be used to display statistics for MOE ratings on each operator. To boost overall profitability for a manufacturing plant, machine operators are sometimes compensated with a salary bonus based on their MOE ratings.", "Engineering,_Manufacturing": 1.0000047684, "qwen": "Yes"}
{"id": "47959004", "revid": "7852030", "url": "https://en.wikipedia.org/wiki?curid=47959004", "title": "DFM analysis for stereolithography", "text": "In design for additive manufacturing (DFAM), there are both broad themes (which apply to many additive manufacturing processes) and optimizations specific to a particular AM process. Described here is DFM analysis for stereolithography, in which design for manufacturability (DFM) considerations are applied in designing a part (or assembly) to be manufactured by the stereolithography (SLA) process. In SLA, parts are built from a photocurable liquid resin that cures when exposed to a laser beam that scans across the surface of the resin (photopolymerization). Resins containing acrylate, epoxy, and urethane are typically used. Complex parts and assemblies can be directly made in one go, to a greater extent than in earlier forms of manufacturing such as casting, forming, metal fabrication, and machining. Realization of such a seamless process requires the designer to take in considerations of manufacturability of the part (or assembly) by the process. In any product design process, DFM considerations are important to reduce iterations, time and material wastage.\nChallenges in stereolithography.\nMaterial.\nExcessive setup specific material cost and lack of support for 3rd party resins is a major challenge with SLA process:. The choice of material (a design process) is restricted by the supported resin. Hence, the mechanical properties are also fixed. When scaling up dimensions selectively to deal with expected stresses, post curing is done by further treatment with UV light and heat. Although advantageous to mechanical properties, the additional polymerization and cross linkage can result in shrinkage, warping and residual thermal stresses. Hence, the part shall be designed in its 'green' stage i.e. pre-treatment stage.\nSetup and process.\nSLA process is an additive manufacturing process. Hence, design considerations such as orientation, process latitude, support structures etc. have to be considered.\nOrientation affects the support structures, manufacturing time, part quality and part cost. Complex structures may fail to manufacture properly due to orientation which is not feasible resulting in undesirable stresses. This is when the DFM guidelines can be applied. Design feasibility for stereolithography can be validated by analytical as well as on the basis of simulation and/or guidelines \nRule-based DFM considerations.\nRule-based considerations in DFM refer to certain criteria that the part has to meet in order to avoid failures during manufacturing. Given the layer-by-layer manufacturing technique the process follows, there isn't any constraint on the overall complexity that the part may have. But some rules have been developed through experience by the printer developer/academia which must be followed to ensure that the individual features that make up the part are within certain 'limits of feasibility'.\nPrinter constraints.\nConstraints/limitations in SLA manufacturing comes from the printer's accuracy, layer thickness, speed of curing, speed of printing etc. Various printer constraints are to be considered during design such as:\nSupport structures.\nA point needs support if:\nWhile printing, support structures act as a part of design hence, their limitations and advantages are kept in mind while designing. Major considerations include:\nPart deposition orientation.\nPart orientation is a very crucial decision in DFM analysis for SLA process. The build time, surface quality, volume/number of support structures etc. depend on this. In many cases, it is also possible to address the manufacturability issues just by reorienting the part. For example, an overhanging geometry with shallow angle may be oriented to ensure steep angles. Hence, major considerations include:\nPlan-based DFM considerations.\nPlan-based considerations in DFM refer to criteria that arise due to process plan. These are to be met in order to avoid failures during manufacturing of a part that may be satisfy the rule-based criteria but may have some manufacturing difficulties due to sequence in which features are produced.\nGeometric tailoring.\nGeometric Tailoring bridges the mismatch of material properties and process differences described above. Both functionality and manufacturability issues are addressed. Functionality issues are addressed through 'tailoring' of dimensions of the part to compensate the stress and deflection behavior anomalies. Manufacturability issues are tackled through identification of difficult to manufacture geometric attributes (an approach used in most DFM handbooks) or through simulations of manufacturing processes. For RP-produced parts (as in SLA), the problem formulations are called material-process geometric tailoring (MPGT)/RP.\nFirst, the designer specifies information such as: Parametric CAD model of the part; constraints and goals on functional, geometry, cost and time characteristics; analysis models for these constraints and goals; target values of goals; and preferences for the goals.\nDFM problem is then formulated as the designer fills in the MPGT template with this information and sends to the manufacturer, who fills in the remaining 'manufacturing relevant' information. With the completed formulation, the manufacturer is now able to solve the DFM problem, performing GT of the part design. Hence, the MPGT serves as the digital interface between the designer and the manufacturer.\nVarious Process Planning (PP) strategies have been developed for geometric tailoring in SLA process.\nDFM frameworks.\nThe constraints imposed by the manufacturing process are mapped onto the design. This helps in identification of DFM problems while exploring process plans by acting as a retrieval method. Various DFM frameworks are developed in literature. These frameworks help in various decision making steps such as:\nExternal links.\nDfm2U Live", "Engineering,_Manufacturing": 1.0000036955, "qwen": "Yes"}
{"id": "48010091", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=48010091", "title": "Virtual machining", "text": "Virtual machining is the practice of using computers to simulate and model the use of machine tools for part manufacturing. Such activity replicates the behavior and errors of a real environment in virtual reality systems. This can provide useful ways to manufacture products without physical testing on the shop floor. As a result, time and cost of part production can be decreased.\nApplications.\nVirtual machining provides various benefits:\nFuture research works.\nSome suggestions for the future studies in virtual machining systems are presented as:", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "598949", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=598949", "title": "Integrated circuit layout", "text": "In integrated circuit design, integrated circuit (IC) layout, also known IC mask layout or mask design, is the representation of an integrated circuit in terms of planar geometric shapes which correspond to the patterns of metal, oxide, or semiconductor layers that make up the components of the integrated circuit. Originally the overall process was called tapeout, as historically early ICs used graphical black crepe tape on mylar media for photo imaging (erroneously believed to reference magnetic data—the photo process greatly predated magnetic media). \nWhen using a standard process—where the interaction of the many chemical, thermal, and photographic variables is known and carefully controlled—the behaviour of the final integrated circuit depends largely on the positions and interconnections of the geometric shapes. Using a computer-aided layout tool, the layout engineer—or layout technician—places and connects all of the components that make up the chip such that they meet certain criteria—typically: performance, size, density, and manufacturability. This practice is often subdivided between two primary layout disciplines: analog and digital.\nThe generated layout must pass a series of checks in a process known as physical verification. The most common checks in this verification process are\nWhen all verification is complete, layout post processing is applied where the data is also translated into an industry-standard format, typically GDSII, and sent to a semiconductor foundry. The milestone completion of the layout process of sending this data to the foundry is now colloquially called \"tapeout\". The foundry converts the data into mask data and uses it to generate the photomasks used in a photolithographic process of semiconductor device fabrication.\nIn the earlier, simpler, days of IC design, layout was done by hand using opaque tapes and films, an evolution derived from early days of printed circuit board (PCB) design -- tape-out.\nModern IC layout is done with the aid of IC layout editor software, mostly automatically using EDA tools, including place and route tools or schematic-driven layout tools.\nTypically this involves a library of standard cells.\nThe manual operation of choosing and positioning the geometric shapes is informally known as \"polygon pushing\".", "Engineering,_Manufacturing": 0.9994644523, "qwen": "Yes"}
{"id": "25527301", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=25527301", "title": "Capacitive displacement sensor", "text": "Capacitive displacement sensors \"are non-contact devices capable of high-resolution measurement of the position and/or change of position of any conductive target\". They are also able to measure the thickness or density of non-conductive materials. Capacitive displacement sensors are used in a wide variety of applications including semiconductor processing, assembly of precision equipment such as disk drives, precision thickness measurements, machine tool metrology and assembly line testing. These types of sensors can be found in machining and manufacturing facilities around the world.\nBasic capacitive theory.\nCapacitance is an electrical property which is created by applying an electrical charge to two conductive objects with a gap between them. A simple demonstration is two parallel conductive plates of the same profile with a gap between them and a charge applied to them. In this situation, the Capacitance can be expressed by the equation:\nWhere \"C\" is the capacitance, ε0 is the permittivity of free space constant, \"K\" is the dielectric constant of the material in the gap, \"A\" is the area of the plates, and \"d\" is the distance between the plates.\nThere are two general types of capacitive displacement sensing systems. One type is used to measure thicknesses of conductive materials. The other type measures thicknesses of non conductive materials or the level of a fluid.\nA capacitive sensing system for conductive materials uses a model similar to the one described above, but in place of one of the conductive plates, is the sensor, and in place of the other, is the conductive target to be measured. Since the area of the probe and target remain constant, and the dielectric of the material in the gap (usually air) also remains constant, \"any change in capacitance is a result of a change in the distance between the probe and the target.\" Therefore, the equation above can be simplified to:\nWhere α indicates a proportional relationship.\nDue to this proportional relationship, a capacitive sensing system is able to measure changes in capacitance and translate these changes in distance measurements.\nThe operation of the sensor for measuring thickness of non-conductive materials can be thought of as two capacitors in series, with each having a different dielectric (and dielectric constant). The sum of the thicknesses of the two dielectric materials remains constant but the thickness of each can vary. The thickness of the material to be measured displaces the other dielectric. The gap is often an air gap, (dielectric constant = 1) and the material has a higher dielectric. As the material gets thicker, the capacitance increases and is sensed by the system.\nA sensor for measuring fluid levels works as two capacitors in parallel with constant total area. Again the difference in the dielectric constant of the fluid and the dielectric constant of air results in detectable changes in the capacitance between the conductive probes or plates.\nApplications.\nPrecision positioning.\nOne of the more common applications of capacitive sensors is for precision positioning. Capacitive displacement sensors can be used to measure the position of objects down to the nanometer level. This type of precise positioning is used in the semiconductor industry where silicon wafers need to be positioned for exposure. Capacitive sensors are also used to pre-focus the electron microscopes used in testing and examining the wafers.\nDisc drive industry.\nIn the disc drive industry, capacitive displacement sensors are used to measure the runout (a measure of how much the axis of rotation deviates from an ideal fixed line) of disc drive spindles. By knowing the exact runout of these spindles, disc drive manufacturers are able to determine the maximum amount of data that can be placed onto the drives. Capacitive sensors are also used to ensure that disc drive platters are orthogonal to the spindle before data is written to them.\nPrecision thickness measurements.\nCapacitive displacement sensors can be used to make very precise thickness measurements. Capacitive displacement sensors operate by measuring changes in position. If the position of a reference part of known thickness is measured, other parts can be subsequently measured and the differences in position can be used to determine the thickness of these parts. In order for this to be effective using a single probe, the parts must be completely flat and measured on a perfectly flat surface. If the part to be measured has any curvature or deformity, or simply does not rest firmly against the flat surface, the distance between the part to be measured and the surface it is placed upon will be erroneously included in the thickness measurement. This error can be eliminated by using two capacitive sensors to measure a single part. Capacitive sensors are placed on either side of the part to be measured. By measuring the parts from both sides, curvature and deformities are taken into account in the measurement and their effects are not included in the thickness readings.\nThe thickness of plastic materials can be measured with the material placed between two electrodes a set distance apart. These form a type of capacitor. The plastic when placed between the electrodes acts as a dielectric and displaces air (which has dielectric constant of 1, different from the plastic). Consequently, the capacitance between the electrodes changes. The capacitance changes can then be measured and correlated with the material's thickness.\nCapacitive sensors circuits can be constructed that are able to detect changes in capacitance on the order of a 10−5 picofarads (10 attofarads).\nNon-conductive targets.\nWhile capacitive displacement sensors are most often used to sense changes in position of conductive targets, they can also be used to sense the thickness and/or density of non-conductive targets as well. A non-conductive object placed in between the probe and conductive target will have a different dielectric constant than the air in the gap and will therefore change the Capacitance between probe and target. (See the first equation above) By analyzing this change in capacitance, the thickness and density of the non-conductor can be determined.\nMachine tool metrology.\nCapacitive displacement sensors are often used in metrology applications. In many cases, sensors are used “to measure shape errors in the part being produced. But they also can measure the errors arising in the equipment used to manufacture the part, a practice known as machine tool metrology”. In many cases, the sensors are used to analyze and optimize the rotation of spindles in various machine tools, examples include surface grinders, lathes, milling machines, and air bearing spindles. By measuring errors in the machines themselves, rather than simply measuring errors in the final products, problems can be dealt with and fixed earlier in the manufacturing process.\nAssembly line testing.\nCapacitive displacement sensors are often used in assembly line testing. Sometimes they are used to test assembled parts for uniformity, thickness or other design features. At other times, they are used to simply look for the presence or absence of a certain component, such as glue. Using capacitive sensors to test assembly line parts can help to prevent quality concerns further along in the production process.\nComparison to eddy current displacement sensors.\nCapacitive displacement sensors share many similarities to eddy current (or inductive) displacement sensors; however capacitive sensors use an electric field as opposed to the magnetic field used by eddy current sensors This leads to a variety of differences between the two sensing technologies, with the most notable differences being that capacitive sensors are generally capable of higher resolution measurements, and eddy current sensors work in dirty environments while capacitive sensors do not.", "Engineering,_Manufacturing": 0.9999986887, "qwen": "Yes"}
{"id": "4671692", "revid": "39641301", "url": "https://en.wikipedia.org/wiki?curid=4671692", "title": "Power electronic substrate", "text": "The role of the substrate in power electronics is to provide the interconnections to form an electric circuit (like a printed circuit board), and to cool the components. Compared to materials and techniques used in lower power microelectronics, these substrates must carry higher currents and provide a higher voltage isolation (up to several thousand volts). They also must operate over a wide temperature range (up to 150 or 200 °C).\nDirect Bonded Copper (DBC) substrate.\nDBC substrates are commonly used in power modules, because of their very good thermal conductivity. They are composed of a ceramic material tile with a sheet of copper bonded to one or both sides by a high-temperature oxidation process (the copper and substrate are heated to a carefully controlled temperature in an atmosphere of nitrogen containing about 30 ppm of oxygen; under these conditions, a copper-oxygen eutectic forms which bonds successfully both to copper and the oxides used as substrates). The top copper layer can be preformed prior to firing or chemically etched using printed circuit board technology to form an electrical circuit, while the bottom copper layer is usually kept plain. The substrate is attached to a heat spreader by soldering the bottom copper layer to it.\nA related technique uses a seed layer, photoimaging, and then additional copper plating to allow for fine lines (as small as 50 micrometres) and through-vias to connect front and back sides. This can be combined with polymer-based circuits to create high density substrates that eliminate the need for direct connection of power devices to heat sinks.\nOne of the main advantages of the DBC vs other power electronic substrates is their low coefficient of thermal expansion, which is close to that of silicon (compared to pure copper). This ensures good thermal cycling performances (up to 50,000 cycles). The DBC substrates also have excellent electrical insulation and good heat spreading characteristics.\nCeramic material used in DBC include:\nActive Metal Brazed (AMB) substrate.\nAMB consists of a metal foil soldered to the ceramic baseplate using solder paste and high temperature (800 °C – 1000 °C) under vacuum. Although AMB is electrically very similar to DBC, it is typically suited for small production lots due to the unique process requirements.\nInsulated Metal substrate (IMS).\nIMS consists of a metal baseplate (aluminium is commonly used because of its low cost and density) covered by a thin layer of dielectric (usually an epoxy-based layer) and a layer of copper (35 μm to more than 200 μm thick). The FR-4-based dielectric is usually thin (about 100 μm) because it has poor thermal conductivity compared to the ceramics used in DBC substrates.\nDue to its structure, the IMS is a single-sided substrate, i.e. it can only accommodate components on the copper side. In most applications, the baseplate is attached to a heatsink to provide cooling, usually using thermal grease and screws. Some IMS substrates are available with a copper baseplate for better thermal performances.\nCompared to a classical printed circuit board, the IMS provides a better heat dissipation. It is one of the simplest ways to provide efficient cooling to surface mount components.", "Engineering,_Manufacturing": 0.999989748, "qwen": "Yes"}
{"id": "44940919", "revid": "754619", "url": "https://en.wikipedia.org/wiki?curid=44940919", "title": "LSP Technologies", "text": "LSP Technologies, Inc. (also known as LSPT) located in Dublin, Ohio. The company provides laser peening surface enhancement services and equipment, and other laser technologies.\nHistory.\nThe company founder, \"Jeff Dulaney\", earned his Ph.D. in Physics at the University of Pittsburgh in 1986, then worked at Battelle Columbus Laboratory from 1987 to 1994 as a physicist in the laser department. He helped design and build the first industrial laser shock peening system for \"Wagner Laser Technologies\" in the early 1990s. Dr. Dulaney acquired Battelle’s laser shock peening patent rights and formed LSP Technologies, Inc. in February 1995. \"Dr. Allan Clauer\", an original patent holder of the laser peening process, and a Battelle inventor of the laser shock peening process, joined LSPT as Vice-President later in 1995.\nIn 1996 to 1999, LSPT assembled and delivered three high power ND: Glass laser peening systems to General Electric Aviation in Cincinnati, Ohio. LSPT also won several Small Business Innovation Research (SBIR) awards for laser peening, laser bond inspection, and laser land mine neutralization. In March 2003 LSPT began production laser peen processing on 4th stage IBR in Pratt & Whitney’s F119 engine for the F-22 Raptor. In 2009 LSPT began laser peening production services for power generation and forging industries. In 2012, LSPT delivered a laser bond inspection system to the Boeing Company in Seattle, WA.\nLSPT is an AS9100 certified company for Laser Processing Services and Equipment Design.\nInventions.\nLSPT holds over 54 patents in laser peening, and many more on laser bond inspection and laser applications.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "39508743", "revid": "1166808676", "url": "https://en.wikipedia.org/wiki?curid=39508743", "title": "Disc cutter", "text": "A disc cutter is a specialised, often hand-held, power tool used for cutting hard materials, ceramic tile, metal, concrete, and stone for example. This tool is very similar to an angle grinder, chop saw, or even a die grinder, with the main difference being the cutting disc itself (a circular diamond blade, or resin-bonded abrasive cutting wheel for a disc cutter vs. an abrasive grinding wheel for an angle grinder). This tool is highly efficient at cutting very hard materials, especially when compared to hand tools.\nDiscs.\nOften cutting discs, also known as cut-off wheels, are made from a solid abrasive disc. These discs are often used for cutting metal; they are composed of an abrasive mix of grit and adhesive that is formed into a thin, rigid disc with fiber webbing running through it for strength. Some discs used for cutting ceramic tile or stone are made from a solid disc with an edge coated with diamond grit. The most common size for these cutting wheels is inches in diameter; however they can range from 2 to 16 inches in diameter with a thickness range from .045 in. to .125 in. Type 1 discs are flat, and type 27 discs have a raised hub. These wheels are strong but are not immune to breaking. If a cutting wheel breaks while in use, fragments could injure the operator or nearby co-workers. To avoid breaking cutting discs, never exceed the maximum speed (RPM) specified on the disc, and do not overload the disc by cutting with excess force or jamming the wheel into your workpiece.\nApplications.\nMany manual cutting tasks require a hand-held grinder using a cutting wheel. Metal fabrication is one of the most common uses for cutting wheels. Cutting sheet metal, sizing metal stock for welding, cutting a weld to re-weld it, and cutting and notching steel pipe are just a few examples. Die grinders and chop saws are other common tools used with cutting discs.\nSmaller projects and smaller or more precise cuts may require a die grinder equipped with a cutting wheel. These cutting wheels or discs are extremely thin and often less than 2 inches in diameter. Because they are so thin, they are commonly made of metal and have a diamond-coated edge as the abrasive. This type of disc cutter is good for sheet metal and for lightweight or thin materials. Thicker or heavier materials will need a larger disc cutter.\nFor long straight cuts on sheet metal or for light cut-off work, a standard circular saw is used with a -inch cutting wheel. These cutting discs are made just like the smaller wheels of an angle grinder, with resin bonded abrasive material, or are of metal with a diamond-coated edge.\nA cutoff saw is used for cutting larger items, like heavy metal stock, metal studs, and for cutting large metal pipe. The cutting discs for this tool are usually 10 or 12 inches in diameter, with a composition like that of the smaller wheels mentioned above. When cutting heavy materials the cutting discs may require lubrication or coolant to prevent overheating. The cutoff saw is for making clean straight 90 degree cuts through the material.", "Engineering,_Manufacturing": 1.0000083447, "qwen": "Yes"}
{"id": "51725805", "revid": "5545776", "url": "https://en.wikipedia.org/wiki?curid=51725805", "title": "BOD bottle", "text": "BOD Bottle or an incubation bottle is a main apparatus used for the Biological Oxygen Demand (BOD) test. During the five-day BOD or BOD5 test process, the BOD bottle is used for incubating diluted samples under the 20 °C or 68 °F of temperature.\nStructure.\nThe bottle is normally designed to have a special shoulder radius to push out all air from the inside of the bottle when a sample solution is being filled. According to Method 5210 in \"Standard Methods for the Examination of Water and Wastewater\", the BOD bottle should include a ground-glass stopper and a flared mouth which form a water seal preventing the air from the outside of the bottle coming in. Method 5210 also recommends to use a paper, a foil or a plastic cup to cap over the mouth of the bottle reducing the evaporation during the incubation. Generally, the side of the BOD bottle is permanently screened with white writing area, and is printed with a specific number; both for the aid of the sample identification.\nThere are two kinds of stopper: the Glass Pennyhead and the Glass Robotic stopper.\nThere are many BOD bottle sizes. The dose of the mixture of the solution (nutrient, mineral and buffer solution) is related to the size of the bottle. For the Standard Methods 5210, the BOD bottle “having 60 mL or greater capacity (300-mL)” is mentioned as one of the apparatus for the BOD test. A 60 mL BOD bottle is available and listed as \"often convenient\" by EPA (Environmental Protection Agency) Method 405.1. However, EPA Method 405.1 was written in 1974 and is no longer an EPA-approved method per 40CFR Part 136.\nMaterials.\nGlass is a material being specified in the Standard Methods 5210 of the BOD5 test. The glass bottles are manufactured from Type 1 borosilicate glass.\nA black BOD bottle is coated with PVC plastic that blocks visible light. Black bottles are used in marine photosynthesis projects which needs to compare oxygen levels in light and dark conditions.\nIt is a carbon-coated polyethylene terephthalate (PET) bottle that is solely manufactured by Environmental Express in Charleston, SC. The bottle is lightweight, unbreakable, and recyclable. Since the bottle is designed for single-use, it eliminates any potential for cross-contamination between samples. The bottle does not require any resources nor energy for cleaning and rinsing as it is disposable. CBOD bottle is also claimed to be cheaper, and cause less contamination in the sample solution than the conventional- BOD bottle.", "Engineering,_Manufacturing": 0.9999307394, "qwen": "Yes"}
{"id": "4752523", "revid": "27015025", "url": "https://en.wikipedia.org/wiki?curid=4752523", "title": "National Production Authority", "text": "The National Production Authority (NPA) was an agency of the United States government which developed and promoted the production and supply of materials and facilities necessary for defense mobilization. It was part of the Department of Commerce.\nThe agency was created by Department Order 123, issued September 11, 1950, under authority of the Defense Production Act of 1950 and Executive Order 10161 (issued September 9, 1950). The organization's function was to ensure the needs of the civilian economy were adequately represented in defense mobilization efforts, and that small businesses were participating in defense contracts.\nIn 1951, after the escalation of the Korean War, the NPA was placed under the control of the Defense Production Administration in the Office of Defense Mobilization. \nThe NPA was abolished by Department Order 152, issued October 1, 1953. Its functions were dispersed among a number of successor agencies, including the Business and Defense Services Administration (1953–1970); the Bureau of Domestic Commerce (1970–1972); the Domestic and International Business Administration (1972–1977); the Industry and Trade Administration (1977–1980); and the International Trade Administration (1980–present).", "Engineering,_Manufacturing": 0.9989236593, "qwen": "Yes"}
{"id": "22516047", "revid": "456858", "url": "https://en.wikipedia.org/wiki?curid=22516047", "title": "Sterling Armaments Company", "text": "The Sterling Engineering Company Ltd was an arms manufacturer based in Dagenham, famous for manufacturing the Sterling submachine gun (L2A3), ArmaLite AR-18 and Sterling SAR-87 assault rifles and parts of Jaguar cars. The company went bankrupt in 1988.\nDuring World War II, engineers George Lanchester and George William Patchett oversaw the manufacture of the Lanchester submachine gun. Patchett afterwards went on to design the Patchett machine carbine which, after a competitive trial in 1947, was adopted by the British Army in 1953 as the L2A1 Sterling submachine gun, replacing the Sten gun. The weapon was later upgraded to the L2A3, the Sterling Mk IV.\nThe Sterling brand name was revived in 2016 by James Edmiston, a former director of the original company. It is however a dormant company, according to accounts filed with Companies House, with no stated plans to do any business beyond engraving services.", "Engineering,_Manufacturing": 0.9999724627, "qwen": "Yes"}
{"id": "8603403", "revid": "26021349", "url": "https://en.wikipedia.org/wiki?curid=8603403", "title": "Wright Cadet", "text": "The Wright Cadet was a low floor midibus body built on the DAF/VDL SB120 chassis by Wrightbus between 2000 and 2006. It was sold via VDL dealer Arriva Bus & Coach. Of the 681 produced, 366 were for Arriva subsidiaries including eight for its Netherlands subsidiary. Bus Éireann purchased 35.\nVolvo Merit.\nThe SB120/Cadet combination was also sold through Volvo Buses for a time following the withdrawal from sale of its own B6BLE chassis in 2002 without a direct replacement. Cadets sold through Volvo were marketed as the Volvo Merit, although they were identical to Cadets sold through Wrightbus.", "Engineering,_Manufacturing": 0.9999052286, "qwen": "Yes"}
{"id": "31594183", "revid": "17005465", "url": "https://en.wikipedia.org/wiki?curid=31594183", "title": "List of semiconductor fabrication plants", "text": "This is a list of semiconductor fabrication plants. A semiconductor fabrication plant is where integrated circuits (ICs), also known as microchips, are manufactured. They are either operated by Integrated Device Manufacturers (IDMs) who design and manufacture ICs in-house and may also manufacture designs from design-only (fabless firms), or by pure play foundries who manufacture designs from fabless companies and do not design their own ICs. Some pure play foundries like TSMC offer IC design services, and others, like Samsung, design and manufacture ICs for customers, while also designing, manufacturing and selling their own ICs.\nOpen plants.\nOperating fabs include:\nNumber of open fabs currently listed here: \nClosed plants.\nNumber of closed fabs currently listed here: \nReferences.\nSamsung capacity", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "31617271", "revid": "5984052", "url": "https://en.wikipedia.org/wiki?curid=31617271", "title": "Operational maintenance", "text": "Operational maintenance is the care and minor maintenance of equipment using procedures that do not require detailed technical knowledge of the equipment’s or system’s function and design. This category of operational maintenance normally consists of inspecting, cleaning, servicing, preserving, lubricating, and adjusting, as required. Such maintenance may also include minor parts replacement that does not require the person performing the work to have highly technical skills or to perform internal alignment.\nAs the term implies, operational maintenance, is performed by the operator of the equipment. Its purpose is threefold: (1) to make the operator aware of the state of readiness of the equipment; (2) to reduce the delays that would occur if a qualified technician had to be called every time a simple adjustment were needed; and (3) to release technicians for more complicated work\nThis form of preventative maintenance can be performed in any setting where machines, equipment, or vehicles are used. This may include manufacturing plants and factories, as well as automotive shops. In many commercial buildings, heating and cooling engineers perform operational maintenance tasks on furnaces, boilers, and air conditioners.\nSome operational maintenance responsibilities can be as simple as inspecting the machine to spot any changes or issues. This allows the operator to detect a potential danger, such as loose fasteners or debris that could contribute to an accident. Basic cleaning, including removing debris or excess grease from a machine, is also considered part of operational maintenance.\nDepending on the type of equipment in use, operators may also be responsible for replacing worn out filters or cartridges, or removing and replacing a worn belt, cutting tool, or grinding stone. Operational maintenance may entail keeping machinery well lubricated to reduce the risk of friction or failure. Many basic machine adjustments needed during the course of operation also fall within this category of preventative maintenance.", "Engineering,_Manufacturing": 0.9966187477, "qwen": "Yes"}
{"id": "1710185", "revid": "33582079", "url": "https://en.wikipedia.org/wiki?curid=1710185", "title": "Interference fit", "text": "An interference fit, also known as a pressed fit or friction fit, is a form of fastening between two tightfitting mating parts that produces a joint which is held together by friction after the parts are pushed together. \nDepending on the amount of interference, parts may be joined using a tap from a hammer or \"pressed\" together using a hydraulic ram. Critical components that must not sustain damage during joining may also be cooled significantly below room temperature to shrink one of the components before fitting. This method allows the components to be joined without force and produces a shrink fit interference when the component returns to normal temperature. Interference fits are commonly used with aircraft fasteners to improve the fatigue life of a joint.\nIntroducing interference between parts.\nThese fits, though applicable to shaft and hole assembly, are more often used for bearing-housing or bearing-shaft assembly. This is referred to as a 'press-in' mounting.\nTightness of fit.\nThe tightness of fit is controlled by amount of interference; the allowance (planned difference from nominal size). Formulas exist to compute allowance that will result in various strengths of fit such as loose fit, light interference fit, and interference fit. The value of the allowance depends on which material is being used, how big the parts are, and what degree of tightness is desired. Such values have already been worked out in the past for many standard applications, and they are available to engineers in the form of tables, obviating the need for re-derivation.\nAs an example, a shaft made of 303 stainless steel will form a tight fit with allowance of . A slip fit can be formed when the bore diameter is wider than the rod; or, if the rod is made 12–20μm under the given bore diameter. \nAn example:\nThe allowance per inch of diameter usually ranges from (0.1–0.25%), (0.15%) being a fair average. Ordinarily the allowance per inch decreases as the diameter increases; thus the total allowance for a diameter of might be , 0.2%), whereas for a diameter of the total allowance might not be over i.e., 0.11–0.12%). The parts to be assembled by forced fits are usually made cylindrical, although sometimes they are slightly tapered. Advantages of the taper form are: the possibility of abrasion of the fitted surfaces is reduced; less pressure is required in assembling; and parts are more readily separated when renewal is required. On the other hand, the taper fit is less reliable, because if it loosens, the entire fit is free with but little axial movement. Some lubricant, such as white lead and lard oil mixed to the consistency of paint, should be applied to the pin and bore before assembling, to reduce the tendency toward abrasion.\nAssembling.\nThere are two basic methods for assembling an oversize shaft into an undersized hole, sometimes used in combination: force and thermal expansion or contraction.\nForce.\nThere are at least three different terms used to describe an interference fit created via force: press fit, friction fit, and hydraulic dilation.\nPress fit is achieved with presses that can press the parts together with very large amounts of force. The presses are generally hydraulic, although small hand-operated presses (such as arbor presses) may operate by means of the mechanical advantage supplied by a jackscrew or by a gear reduction driving a rack and pinion. The amount of force applied in hydraulic presses may be anything from a few pounds for the tiniest parts to hundreds of tons for the largest parts.\nThe edges of shafts and holes are chamfered (beveled). The chamfer forms a guide for the pressing movement, helping to distribute the force evenly around the circumference of the hole, to allow the compression to occur gradually instead of all at once, thus helping the pressing operation to be smoother, to be more easily controlled, and to require less power (less force at any one instant of time), and to assist in aligning the shaft parallel with the hole it is being pressed into. In the case of train wheelsets the wheels are pressed onto the axles by force.\nThermal expansion or contraction.\nMost materials expand when heated and shrink when cooled. Enveloping parts are heated (e.g., with torches or gas ovens) and assembled into position while hot, then allowed to cool and contract back to their former size, except for the compression that results from each interfering with the other. This is also referred to as shrink-fitting. Railroad axles, wheels, and tires are typically assembled in this way. Alternatively, the enveloped part may be cooled before assembly such that it slides easily into its mating part. Upon warming, it expands and interferes. Cooling is often preferable as it is less likely than heating to change material properties, e.g., assembling a hardened gear onto a shaft, where the risk exists of heating the gear too much and drawing its temper.", "Engineering,_Manufacturing": 1.0000083447, "qwen": "Yes"}
{"id": "6311788", "revid": "1168351724", "url": "https://en.wikipedia.org/wiki?curid=6311788", "title": "Integrated Micro-Electronics, Inc.", "text": "Integrated Micro-electronics, Inc. (abbreviated as IMI, ) provides electronics manufacturing services (EMS) and power semiconductor assembly and test services (SATS) with manufacturing facilities in Asia, Europe, and North America. Its headquarters is located in Biñan, Laguna, Philippines.\nIMI serves original equipment manufacturers (OEMs) in diversified markets that include those in the automotive, industrial, medical, telecommunications infrastructure, storage device, and consumer electronics industries. Its customized solutions range from design and engineering solutions, advance manufacturing engineering capabilities, new product introduction services, manufacturing solutions, reliability tests, failure analysis, equipment calibration capabilities, test and system development, and support and fulfillment. The manufacturing portfolio of AC Industrials, a wholly owned subsidiary of Ayala Corporation, IMI is listed in the Philippine Stock Exchange.\nHistory.\nIMI started on August 8, 1980 as a joint venture between Ayala Corporation and Resins, Inc. With its headquarters in Muntinlupa, they were just a workforce of around 100 employees with total fixed assets of US$3,700,290 and it is engaged in the assembly of integrated circuits. In 1982, it took a contract manufacturing with its hard disk drive sub-assembly operations and, in 1986, it started the assembly of automotive hybrid integrated circuits.\nIn the year 1988, the company ventured into custom printed circuit board assembly and operations and in the next years, it offered standard printed circuit board assembly services with the acquisition of automated surface mounting equipment, and eventually, full product assembly and flexible printed circuit board assembly operations.\nThe company moved its manufacturing site in 1995 from Cupang, Muntinlupa to its present location at the Laguna Technopark. In 1998, IMI commenced offering hardware and software design services, that transitions the company to a total electronics manufacturing service provider. By 2001, IMI had three manufacturing sites in the Philippines.\nAs of 2023, IMI has 20 manufacturing sites of +330,072m² with more than 14,076 employees across 10 countries. From an EMS company, it expanded its scope to include EMS and Power Semiconductor Assembly and Test Services. IMI is also into prototyping, manufacturing, product test development, testing and order fulfillment.\nGlobal expansion.\nIMI has multiple manufacturing sites in Bulgaria, China, Czech Republic, United Kingdom, Germany, Mexico, and the United States providing solutions to original equipment manufacturers (OEMs) catering for both regional and international markets.\nThe company began to establish its presence outside the Philippines. In 2005, IMI acquired the EMS assets of Saturn Electronics and Engineering Inc. in the US and the Speedy-Tech Electronics Ltd of Singapore. The acquisition of Speedy-Tech eventually led to the establishment of IMI's presence in China—through three facilities, namely, two in Shenzhen and one in Jiaxing.\nBy 2006, the company became one of the top 50 EMS companies in the world.\nIMI strengthened its presence in Europe and South America in 2011 through the acquisition of EPIQ NV subsidiaries in Bulgaria, the Czech Republic, and Mexico.\nIn August 2016, IMI announced that it will acquire 76.01 percent stake in the optical bonding and display solutions provider, VIA optronics GmbH. This brings new technology to IMI for display solution in the automotive industry by providing automotive camera and display monitor solutions for advanced driver assistance systems (ADAS).\nIMI also acquired 80 percent stake of Surface Technology International (STI) Enterprise, in 2017, through the subsidiary Integrated Micro-Electronics UK Ltd. STI is an electronics design and manufacturing solutions in both printed circuit board assembly and full box-build manufacturing for high-reliability industries such as aerospace and defense markets. It has two manufacturing sites in United Kingdom, as well as in Cebu, Philippines, and a design center in London.\nDomestic expansion.\nIn 2010, IMI acquired PSi Technologies, a power semiconductor assembly and test service provider. The company bought the minority shares of PSi Technologies in 2014.\nIn January 2015, IMI acquired the remaining shares of PSi from private investment firms Narra Venture Capital II LP and Narra Associates II Limited.\nIn 2016, Ayala Corporation announced that it will consolidate its businesses in car dealership and industrial operations into a wholly owned subsidiary AC Industrials—this includes IMI. IMI has the major role of being the manufacturing arm of AC Industrials for its wide range of portfolio. The first project was the motorcycle assembly factory in partnership with KTM AG group under KTM Asia Motorcycle.\nStock exchange listing.\nOn January 21, 2010, IMI listed 1.137 billion common shares in the Philippine Stock Exchange.\nIt has completed its follow-on offering and listing of 215,000,000 common shares on December 5, 2014. IMI has 1,856,899,921 outstanding shares, as of March 31, 2015.\nCapabilities.\nIMI is an EMS player in the automotive industry. Aside from assembly services, IMI provides automotive tier 1 suppliers and original equipment manufacturer services such as design and product development and test systems development. The company manufactures safety electronics for vehicles such as automotive cameras and airbag controls.\nThe company also produces access control devices design against theft and dosimeters. It is also involved in the robotics industry. In addition to these, IMI also produces medical diagnostic devices and telecom infrastructure devices.\nIts technology groups collaborate with one another and with customers to develop platforms or baseline technologies in areas such as camera and imaging, motor drives, power modules, lighting systems, short range wireless, human-to-machine interface, sensors, and medical electronics.\nEngineering.\nDesign & Development.\nThe Design & Development (D&D) group of IMI focuses on complex automation deployments in different internal segments, business units, and external customers which includes applications in automation handling, dispensing, screwing, and customized auto feeding system for mass production. It has an extensive competencies in electronic design, mechanical design, and software development, and building platforms in the areas of automotive cameras, motor drives, and power modules. D&D provides full design services from concept to product validation. Contract design and joint development solutions of IMI is integrated in D&D, which includes power electronics, embedded systems, camera and imaging systems, motor drives, power modules, power semiconductors, LED lighting and display design, and low and high radio-frequency design.\nAdvanced Manufacturing Engineering.\nThe Advanced Manufacturing Engineering (AME) works on several industrial microelectromechanical systems-based inertial measurement unit modules, commercial laser display modules, and automotive camera modules, including the IMI minicube camera platform. AME is developing a fully automated assembly line that manufactures a complex electro-mechanical assembly for automotive safety and security electronic control at IMI Jiaxing as well as in IMI Mexico. AME is collaborating with D&D on a low cost automotive camera and power modules.\nTest & Systems Development.\nIMI's Test & Systems Development (TSD) expanded the development and application of fully automated test systems that integrate common backend process requirements—product marking, automated inspection, and unit sorting. It also developed an innovative test solutions for automotive electronics, EV vehicle boards and power electronics. It designed and implemented a new line of testers for power module devised and collaborated with a customer to build a fully automated tester for power train boards for EV.\nCamera & Vision Technology.\nThe Camera and Vision Technology (CVT) group equips IMI to be ready with autonomous driving. A spun off from the D&D in 2016, the group focuses on developing vision-based products that support the different Advanced Driver Assistance Systems (ADAS) applications. In 2017, The group synced with AME and TSD to become a one-stop shop solution for camera design, prototype development and mass production.\nManufacturing.\nManufacturing Solutions.\nAs initially an EMS company, the manufacturing arm of IMI produces products for original equipment manufacturers (OEMs). Some manufacturing solutions of IMI are automotive camera, power modules, complete box builds, sub-assembly, component assembly, precision assembly and automated through-hole assembly.\nPlastic Capability.\nIMI also manufactures plastic parts in Asia, Europe and North America that makes box-build capabilities accessible to its partners in automotive, industrial and consumer electronics industries. It integrates parts such as covers, housings and connectors in sub-assemblies, specializing in electronic box-build. Low pressure molding and thermoforming are the process capabilities of IMI.\nPrecision Machining.\nThe Precision Machining group is capable of fabricating components for various parts of any material for its customers. Some of the processes includes, material preparation in vertical and horizontal band saw, squaring on conventional machines (milling), CNC machining, finishing grinding deburring machine, coordinate measuring machine (CCM), and metal sheet works.\nMotorcycle Assembly.\nIMI produces motorcycle for the KTM AG group. A joint venture between KTM Asia Motorcycle Manufacturing (KAMMI) and Adventure Cycle Philippines of AC Industrials, IMI assembles four (4) models of the KTM motorcycles in its plant in Laguna, Philippines.\nStarting in 2024, IMI will manufacture motorcycles for Zero.\nSystem Integration.\nThe System Integration group of IMI integrates different subsystem and modules into one large system. It serves a wide variety of complex build-to-print and contract design manufacturing requirements and increases value to systems by adding new functionalities while linking all functions of different systems. IMI combines complex PCBAs, electronics and mechanical assemblies with robotics into one system.\nSubsidiaries and Affiliates.\nIMI has four wholly owned subsidiaries that carry out the business through the various operating entities globally:\nIMI Singapore.\nIMI Singapore or officially IMI International (Singapore) Pte Ltd. wholly owns Speedy-Tech Electronics Ltd. when IMI acquired it on 2005. STEL, which provides EMS and power electronics, manages the China and Singapore operations. IMI Singapore also holds Cooperatief IMI Europe U.A that manages the Europe and Mexico operations from the acquisition of EPIQ NV. IMI ROHQ is also an affiliate that serves as a supervisory, communications and coordinating center for IMI Singapore affiliates and subsidiaries. It holds the stake of IMI in VIA Optronics and IMI UK which has stake in STI Enterprises.\nIMI USA.\nIMI USA, Inc. acts as direct support to the Group's customers by providing program management, customer service, engineering development and prototype manufacturing services. It is also engaged in precision assembly of surface mount technology, chip on flex, chip on board, flip chip on flex, advanced manufacturing process development, engineering development, prototype manufacturing, and small precision assemblies.\nIMI Japan.\nIMI Japan, Inc. offers the services, such as technical, quality assurance, sales and commercial support, to answer the needs diverse range of Japanese-based OEMs. It also functions as a program management center for new business that will be endorsed to other subsidiaries. There are no manufacturing operations in IMI Japan.\nPSi Technologies.\nPSi Technologies, Inc. is a Philippine company, that provides power semiconductor assembly and test services, that IMI bought shares of 56%, and in 2012 it was fully acquired by IMI through the acquisition of the minority of the shares.\nReception.\nIMI received Circuit Assembly's 2007 Service Excellence Award for the Highest Overall Customer Ranking for medium-sized EMS company category. (Circuit Assembly is a US-based electronics industry trade publication that recognizes companies that receive the highest customer service ratings, as judged by their own customers.) The ASEAN Business Advisory Council, hailed IMI as one of the 12 most admired companies in Southeast Asia.\nIMI ranks 18th on the list of top EMS providers in the world based on 2014 EMS-related revenues as reported by Manufacturing Market Insider. It is also the 7th largest EMS player in the automotive industry as reported by New Venture Research based on 2014 EMS-related revenues.\nIMI's Analytical Testing and Calibration (ATC) laboratory was granted accreditation for ISO/IEC 17025:2005 on January 8, 2016, by the Philippine Accreditation Bureau (PAB) of the Department of Trade and Industry. The accreditation demonstrates technical competence for the scope specified by the PAB and the operation of a laboratory quality management system that meets the principles of .\nSocial involvement.\nIMI has a corporate social responsibility program. IMI began a sustainable community livelihood program through a partnership with ChildFund Foundation and Yakap sa Kaunlaran ng Bata, Inc. (YKBI). Along with this organization IMI, provided the women from the Parents Association of San Pablo and Bay, Laguna, with 10 sewing machines to encourage them toward self-reliance and supplement their entrepreneurial skills. The Parents Associations of both communities are now sewing blouses for Krizia, a garment manufacturer.", "Engineering,_Manufacturing": 0.9999790192, "qwen": "Yes"}
{"id": "6312042", "revid": "32990417", "url": "https://en.wikipedia.org/wiki?curid=6312042", "title": "Pad printing", "text": "Pad printing (also called tampography) is a printing process that can transfer a 2-D image onto a 3-D object (e.g., a ceramic pottery). This is accomplished using an indirect offset (gravure) printing process that involves an image being transferred from the cliché via a silicone pad onto a substrate. Pad printing is used for printing on otherwise difficult to print on products in many industries including medical, automotive, promotional, apparel, and electronic objects, as well as appliances, sports equipment and toys. It can also be used to deposit functional materials such as conductive inks, adhesives, dyes and lubricants. \nPhysical changes within the ink film both on the cliché and on the pad allow it to leave the etched image area in favor of adhering to the pad, and to subsequently release from the pad in favor of adhering to the substrate. \nThe unique properties of the silicone pad enable it to pick the image up from a flat plane and transfer it to a variety of surfaces, such as flat, cylindrical, spherical, compound angles, textures, concave, or convex surfaces.\nHistory.\nWhile crude forms of pad printing have existed for centuries, it was not until the twentieth century that the technology became suitable for widespread use. First gaining a foothold in the watch-making industry following World War II, developments in the late 60s and early 70s, such as silicone pads and more advanced equipment, made the printing method far more practical. The ability to print on formerly unprintable surfaces caught the imaginations of engineers and designers, and as a result pad printing exploded into the mass production marketplace.\nToday, pad printing is a well established technology covering a wide spectrum of industries and applications.\nProcess.\nPlate and ink interface technologies.\nOpen inkwell system.\nOpen ink well systems, the older method of pad printing, used an ink trough for the ink supply, which was located behind the printing plate. A flood bar pushed a pool of ink over the plate, and a doctor blade removes the ink from the plate surface, leaving ink on the etched artwork area ready for the pad to pick up.\nSealed ink cup system.\nSealed ink cup systems employ a sealed container which acts as the ink supply, flood bar and doctor blade all at the same time. A ceramic ring with a highly polished working edge provides the seal against the printing plate.\nPrinting pad.\nPads are three-dimensional objects typically molded of silicone rubber. They function as a transfer vehicle, picking up ink from the printing plate, and transferring it to the part (substrate). They vary in shape and diameter depending on the application.\nThere are two main shape groups: \"round pads\" and long narrow pads called \"bar pads\". Pads are also made in other shapes, called \"loaf pads\". Within each group there are three size categories: small, medium, and large size pads. It is also possible to engineer custom-shaped pads to meet special application requirements.\nImage plate.\nImage plates (also called clichés or print plates) are used to contain the desired artwork \"image\" etched in its surface. Their function is to hold ink in this etched cavity, allowing the pad to pick up this ink as a film in the shape of the artwork, which is then transferred to the substrate.\nThere are two main types of printing plate materials: photopolymer and steel. Photopolymer plates are the most popular, as they are easy to use. These are typically used in short to medium production runs. Steel plates come in two forms: thin steel for medium to long runs, and thick steel for very long runs. Both steel plate types are generally processed by the plate supplier as it involves the use of specialized equipment.\nMulticolor applications can be executed by the coordinated use of several clichés. One image can contain several contrast colors (monochrome) by applying different engraving depths and/or grid resolutions. \nPrinting ink.\nInk is used to mark or decorate parts. It comes in different chemical families to match the type of material to be printed (please consult the substrate compatibility chart for selection).\nPad printing inks are often \"solvent-based\" and require mixing with additives before use. They typically seem dry to the touch within seconds although complete drying (cure) might take a substantially longer period of time. There are FDA approved edible variants that have been developed for human consumption and more ecological variants to reduce the environmental impact. \nThere are many more options. Inks that cure via the use of ultraviolet light are convenient for certain applications. UV inks will not fully cure until UV light hits the ink. UV curable ink can be wiped off many substrates when mistakes are made. They can be cured with UV light in as fast as 1 second of light exposure. This depends on the ink, substrate and the light power and spectrum. UV inks can be reused as the pot life can be high as long as the ink stays clean, blocked from UV light and hasn't broken down from sitting. This same feature makes it easier to clean than some solvent and epoxy like two part component inks. Also there are heat curable inks, which work in much the same way as UV in the sense that there is a \"trigger\" that cures the ink when pulled. Two-component inks usually have a pot life of only a few hours or so. They must be disposed of when they cannot be revived (by means of retarders etc.)\nClimatic conditions will significantly affect the performance of any pad printing ink, especially the open ink well style printers. Too dry conditions can lead to faster evaporation of solvents causing the ink to thicken prematurely and too much moisture can lead to ink issues of \"clumping\" or something similar. Also the climate can affect other aspects of the printing process such as ink pick up and release from the plate to the pad to the substrate, as well as polymer plate to blade chattering or binding due to humidity.\nSubstrate.\nSubstrate is the technical term used to address any parts or materials to be printed. Fixtures vary in materials and complexity depending on the application. Substrates need to be clean and free from surface contamination to allow proper ink adhesion.\nMaking of printing plates.\nThere are two main techniques used to create a printing plate. The traditional technique requires a UV exposure unit and involves photo exposure with film positives and chemical etching. A second technique known as \"computer to plate\" requires a laser engraver and involves automated laser etching. The latter technique is more convenient for short production delays, high precision, stable quality control. \nBoth techniques can be applied on a specialized polymer or steel plate. The standard cycle life that can be expected out of a polymer plate is quite low (50,000 impressions on the high end). By comparison, a hardened steel plate can easily last for over 1 million impressions. \nPrinting application examples.\nPad printing is typically used for applications where print quality, precision or a complex shape is involved. ", "Engineering,_Manufacturing": 0.999910593, "qwen": "Yes"}
{"id": "59034214", "revid": "28481209", "url": "https://en.wikipedia.org/wiki?curid=59034214", "title": "Digital thread", "text": "Digital thread, also known as digital chain, is defined as “the use of digital tools and representations for design, evaluation, and life cycle management.”. It is a data-driven architecture that links data gathered during a Product lifecycle from all involved and distributed manufacturing systems. This data can come from any part of product's lifecycle, its transportation, or its supply chain. Digital thread \"enables the collection, transmission, and sharing of data and information between systems across the product lifecycle\" to enable real-time decision making, gather data, and iterate on the product.\nThe term 'digital thread' was first used in the Global Horizons 2013 report by the USAF Global Science and Technology Vision Task Force. Digital thread was further refined in 2018 by Singh and Willcox at MIT in their paper entitled \"Engineering with a Digital Thread\". In this academic paper the term digital thread is defined as \"a data-driven architecture that links together information generated from across the product lifecycle and is envisioned to be the primary or authoritative data and communication platform for a company’s products at any instance of time.\"\nDigital thread enables \"data to be integrated into one platform, allowing seamless use of and ease of access to all data\".\nApplications.\nDigital twin.\nIdaho National Laboratories describes Digital Twin as \"the merging of integrated and connected data, sensors and instrumentation, artificial intelligence, and online monitoring into a single cohesive unit.\"\nIt is a critical capability of model-based systems engineering (MBSE) and the foundation for a Digital twin, which is defined as \"a digital replica of a physical entity\". In fact, digital thread was first described as related to Digital twin in the Global Horizons 2013 report. Digital thread is a means to gather data for use in the development of a Digital twin; \"some argue [digital thread] is the backbone of digital twin applications\". \"digital thread platforms can capture data from different systems, standardize it, and provide a seamless link between the physical process or product and the digital twin\". The term digital thread is also used to describe the traceability of the digital twin back to the requirements, parts and control systems that make up the physical asset. \nAlthough digital thread and Digital twin are \"every so often understood to be synonymous...they are not the same as Digital Twin relies on real-time data from its physical counterpart\". \"In short, digital thread describes the process while digital twin symbolizes technology\". \"Compared to the digital twin, the digital thread can support decision-making by designing and regulating the data interaction and processing instead of high-fidelity system models\".\nA digital thread enables a Digital twin by ensuring that incoming data is made uniform and easily accessible through the three main data chains:\nEnabling a Digital twin could result in petabytes of data, and \"necessitate the use of highly sophisticated tools and software.\"\nTools.\nDeepLynx.\n\"DeepLynx is an ontological data warehouse with timeseries data support\". It was primarily authored by John Darrington and Cristopher Ritter to tackle Model-Based Systems Engineering (MBSE) tool integrations and warehousing, and has evolved to enable support for digital twin.\nInternet of things.\nA key aspect of digital thread is the Internet of things, whose \"cyber-physical systems, sensors, and so-called smart devices\" are an important source of the data required by digital thread. \"The ability to gather massive amounts of data through the aspired omnipresence of sensors furthermore fuels the emergence of other key technologies\" such as Big data analytics, Artificial intelligence, and Cloud computing. \"Thus, the data collected by using IoT technologies constitute the basis of advanced simulation models, which is in essence the livelihood of the digital twin paradigm and therefore also an integral part of the wider digital thread.\"\nSmart manufacturing.\nBig data analytics and artificial intelligence used in conjunction with Digital Thread are increasingly more required in smart manufacturing applications. Big data analytics is a \"prerequisite for managing highly variable\" data of smart manufacturing processes, gathered through digital thread. Artificial Intelligence can be trained using this data to create \"autonomously self-improving production processes [14] and to facilitate organizational decision-making\". \"the digital thread paradigm not only leads to the accumulation and processing of massive amounts of data but is also shaped by the analytical results these both technologies provide\".", "Engineering,_Manufacturing": 0.9988283515, "qwen": "Yes"}
{"id": "56949784", "revid": "31772205", "url": "https://en.wikipedia.org/wiki?curid=56949784", "title": "Ultima Mk1", "text": "The Ultima Mk1 is a mid-engined concept kit car produced by Noble Motorsport Ltd in 1983 (the company later became Ultima Sports when Ted Marlow and Richard Marlow bought the rights in 1992). The Mk1 was intended to go into production, but before any sold the Ultima Mk2 was introduced, and thus only one Mk1 was made.\nRequired donor parts.\nAs the Ultima Mk1 was a kit car, it required a variety of donor parts to complete. The Mk1 uses the 2.6L V6 and five-speed transaxle from the Renault 30 as well as that car's driveshafts, hubs, wheel bearings and gear lever. It also uses the steering components, front uprights, front hubs, front brakes and handbrake lever from the Mk3 Ford Cortina as well as the radiator from the Austin Princess and rear calipers from the Lancia Beta.\nPerformance.\nThe Mk1 features a square tube space frame chassis and gull-wing doors. Its powered by the 2.6L (2664cc) V6 PRV engine and five-speed transaxle from the Renault 30 producing 96 kW (128.7 hp, 130 PS).", "Engineering,_Manufacturing": 0.99707973, "qwen": "Yes"}
{"id": "59666607", "revid": "44584685", "url": "https://en.wikipedia.org/wiki?curid=59666607", "title": "Costume shop", "text": "A costume shop is a space where costumes for theatrical or film productions are designed, built, and stored for the company or production. Costume designers, builders, seamstresses, and stitchers work in costume shops. The shops themselves can vary in size, from one large room to a house with multiple floors. Costumes from past productions, fabric, jewelry and accessories are often stored in the shop.\nPurpose.\nA costume shop is where the costumes worn on stage for a production are built. Some costume shops have washers for cleaning costumes, fitting rooms, racks for storage or spaces for designers to conceptualize a costume. Some shops allow rentals of their costumes. However, the most common and primary purpose for a costume shop is for building and finishing pieces that go onstage.\nThere is no standard layout for costume shops, though most have stations for stitching or surging, cutting tables, fabric storage, and finishing tables. A large an expansive costume shop style helps work to enable productions to be mounted lavishly and permit study and experimentation at the same time. The process of building a costume requires many steps and stations, which the costume designer first conceptualizes. But before building can begin, the designer must choose where the costumes will come from.\nOnce the show is designed, pieces can come from a multitude of places, but there are commonly four options:\nThe costume shop will search, place orders, create, organize, and dole out the costumes for each production and each character in the manner that best fits the costume and production itself. For instance, not every shoe is cobbled in the shop, or \"in house\"; some are bought and some are borrowed.\nJobs within.\nWithin a costume shop, there are people working on different parts of the creative or accumulative process. The size of the theatre or company will determine whether each job goes to one person, if a group of individuals share more than one job, or if everyone pitches in on everything.\nCostume designer.\nThe costume designer is an integral part of the production's creative team. They work closely with the director to develop a look for the actors onstage that best serves the plot of the play and concept the director has envisioned. \"The Costume Designer seeks inspiration from many sources, including interviews with the actors who will play the characters, and extensive historical and visual research.\" Whether the costume designer is a permanent position or a by-production hire will determine whether they are considered the head of the costume department or shop\nAssistant designer.\nThe assistant designer helps the head designer with the jobs that must be completed. This includes but is not limited to research, shopping, rental acquisition and fittings for actors.\nCutter/draper.\nThe cutter/draper is responsible for making patterns, cutting, fitting and construction of costumes from specific designs or sketches supplied by the designer. \"The Cutter may assist in selecting materials and supervising the costume construction.\" In most shops there are multiple cutters and drapers to ease and spread out work load.\nCostume coordinator/supervisor/shop manager.\nA shop manager is responsible for daily goings on in the shop, much like a manager in a building or restaurant. They deal with the costume budget from the producers, manufacturing and purchasing, as well as work and costume building schedules and production crew requirements.\nStitcher (sewer, seamstress, costume builder).\nA stitcher works on the actual construction of the costumes. The stitcher will sometimes assist during fittings to help with pinning and alterations. This is the entry-level position in a costume shop and often the most common job that is open in a space. A stitcher will help pick up wherever needed, often stretching out from fittings, pinning, and alteration, to textiles, dye working and errands.", "Engineering,_Manufacturing": 0.9896005988, "qwen": "Yes"}
{"id": "29477317", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=29477317", "title": "Automatic lathe", "text": "In metalworking and woodworking, an automatic lathe is a lathe with an automatically controlled cutting process. Automatic lathes were first developed in the 1870s and were mechanically controlled. From the advent of NC and CNC in the 1950s, the term automatic lathe has generally been used for only mechanically controlled lathes, although some manufacturers (e.g., DMG Mori and Tsugami) market Swiss-type CNC lathes as 'automatic'.\nCNC has not yet entirely displaced mechanically automated lathes, as although no longer in production, many mechanically automated lathes remain in service.\nGeneral nomenclature.\nThe term \"automatic lathe\" is still often used in manufacturing in its earlier sense, referring to automated lathes of non-CNC types. The first automatic lathes were mechanically automated and controlled by cams or tracers and pantographs. Thus, before electronic automation via numerical control, the \"automatic\" in the term \"automatic machine tool\" always referred implicitly to \"mechanical\" automation.\nThe earliest mechanically automated lathes were geometric lathes, including rose engine lathes. In industrial contexts during the Machine Age, the term \"automatic lathe\" referred to mechanical screw machines and chuckers.\nSince the maturation of CNC, the implicit dichotomy of \"manual versus automatic\" still exists, but because CNC is so ubiquitous, the term \"automatic\" has lost some of its distinguishing power. All CNC machine tools are automatic, but the usage in the machining industries does not routinely call them by that term. The term \"automatic\", when it is used at all, still often refers implicitly to cam-operated machines. Thus a 2-axis CNC lathe is not referred to as an \"automatic lathe\" even if fully automated.\nSmall- to medium-sized cam-operated automatic lathes are usually called screw machines or automatic screw machines. These machines work on parts that (as a rough guide only) are up to in diameter and in length. Screw machines almost invariably do \"bar work\", meaning a length of bar stock passes through the spindle and is gripped by the chuck (usually a collet chuck). As the part is being machined, the entire length of bar stock is rotated with the spindle. When the part is done, it is 'parted' from the bar, the chuck in released, the bar fed forward, and the chuck closed again, ready for the next cycle. The bar-feeding can happen by various means, including pulling-finger tools that grab the bar and pull or roller bar feed that pushes the bar from behind.\nLarger cam-operated automatic lathes are usually called automatic chucking lathes, automatic lathes, automatic chuckers, automatics, or chuckers. The 'chucker' part of the name comes from the workpieces being discrete blanks, held in a bin called a \"magazine\", and each one takes a turn at being chucked and machined. (This is analogous to the way that each round of ammunition in the magazine of a semi-automatic pistol gets its turn at being chambered.) The blanks are either individual forgings or castings, or they are pre-sawn pieces of billet. However, some members of this family of machine tools turn bar work or work on centers (e.g., the Fay automatic lathe). Regarding bar work of large diameter (for example, or more), it is merely an academic point whether it is called \"screw machine work\" or just \"automatic work\".\nScrew machine.\nScrew machines, being the class of automatic lathes for small- to medium-sized parts, are used in the high-volume manufacture of a vast variety of turned components. During the Swiss screw machining process, the workpiece is supported with a guide bushing, near the cutting tool.\nScrew machine nomenclature.\nSpeaking with reference to the normal definition of the term \"screw machine\", all screw machines are fully automated, whether mechanically (via cams) or by CNC, which means that once they are set up and started, they continue running and producing parts with little human intervention. Mechanical automation came first, beginning in the 1870s; computerized control (via first NC and then CNC) came later, beginning in the 1950s.\nThe name \"screw machine\" is somewhat of a metonym, as screw machines can make parts other than screws or that are not threaded. However, the archetypal use for which screw machines were named was screw-making.\nThe definition of the term \"screw machine\" has changed with changing technology. Any use of the term prior to the 1840s, if it occurred, would have referred ad hoc to any machine tool used to produce screws. That is, there would have been no established differentiation from the term \"screw-cutting lathe\". When turret lathes were developed in the 1840s, the term \"screw machine\" was applied to them in overlapping usage with the term \"turret lathe\". In 1860, when some of the movements, such as turret indexing, were mechanically automated, the term \"automatic screw machine\" was applied, and the term \"hand screw machine\" or \"manual screw machine\" was retronymously applied to the earlier machines. Within 15 years, the entire part-cutting cycle had been mechanically automated, and machines of the 1860 type were retronymously called \"semi-automatic\". From that time on, machines with fully automated cycles were usually called \"automatic screw machines\", and eventually, in the usage of most people in the machining industries, the term \"screw machine\" no longer was used to refer to manual or semi-automatic turret lathes, having become reserved for one class of machine, the fully mechanically automated type. This narrow meaning of \"screw machine\" remained stable from about the 1890s until the 1950s. (Brown & Sharpe continued to call some of their hand-operated turret lathe models \"screw machines\", but most machinists reserved the term for automatics.) Within this class called \"screw machines\" there were variations, such as single-spindle versus multispindle, horizontal-turret versus vertical-turret, etc.\nWith the advent of NC, screw machines diverged into two classes, mechanical and NC. This distinction continues today with mechanical screw machines and CNC screw machines. However, in shop-floor jargon, the term \"screw machine\" by itself is still often understood in context to imply a mechanical screw machine, so the retronym \"mechanical screw machine\" is not consistently used.\nAutomatic chucker.\nAn automatic chucking machine is similar to an automatic screw machine; both use spindles in production. The use of spindles, which are able to drill, bore and cut the workpiece, allows several functions simultaneously on both machines. A key difference between the machines is that the automatic chucker handles larger work, which due to its size is more often chucking work and less often bar work. The Fay automatic lathe was a variant that specialized in turning work on centers. While a screw machine is limited to around practice, automatic chuckers are available that can handle up to chucks. The chucks are air-operated. Many of these machines are multispindle (more than one main spindle).\nWell-known brands of such machines have included National-Acme, Hardinge, New Britain, New Britain-Gridley, Acme-Gridley, Davenport, Bullard Mult-Au-Matic (a vertical multispindle variant), and Thomas Ryder and Son.\nAutomatic chuckers are a class of machine tool specialized to narrow industry niches, such as OEM part suppliers to the automotive industry. They are limited in their economic niches to high-volume production of large parts, which tends to occur only at relatively few companies (compared to smaller work that may be done by small businesses). The market for such machine tools does not generally include local job shops or tool and die shops.\nCam-operated chuckers are fading into history faster than most other non-CNC machine tool classes. This is because the few companies that have them tend to be forced to continually adapt to the latest state of the art (today all CNC) to compete and survive. Cam-op chuckers may be more likely to be scrapped than other types of non-CNC machine tools. Unlike with \"Grandpa's South Bend lathe\" or \"Dad's old Bridgeport knee mill\", virtually no one can afford to keep and use them for sentimental reasons alone. As with most nondigital commercial typesetting machinery (such as Linotype machines).\nChoice of machines and control type.\nMechanical screw machines have been replaced to some extent by CNC lathes (turning centers) and CNC screw machines. However, they are still commonly in operation, and for high-volume production of turned components it is still often true that nothing is as cost-efficient as a mechanical screw machine.\nIn the hierarchy of manufacturing machines, the screw machine sits at the top when large product volumes are needed. An engine lathe sits at the bottom, taking the least time to set up but the most skilled labor and time to actually produce a part. A turret lathe has traditionally been one step above an engine lathe, needing greater set-up time but being able to produce a higher volume of product and usually requiring a lower-skilled operator once the set-up process is complete. Screw machines may require an extensive set-up, but once they are running, a single operator can monitor the operation of several machines.\nThe advent of the CNC lathe (or more properly, CNC turning center) has blurred these distinct levels of production to some extent. The CNC turning center most appropriately fits in the mid-range of production, replacing the turret lathe. However, it is often possible to produce a single component with a CNC turning center more quickly than can be done with an engine lathe. To some extent too, the CNC turning center has stepped into the region traditionally occupied by the (mechanical) screw machine. CNC screw machines do this to an even greater degree, but they are expensive. In some cases they are vital, yet in others a mechanical machine can match or beat overall performance and profitability. It is not unusual for cam-op automatic lathes to beat CNCs on cycle time. CNC offers many benefits, not least CAD/CAM integration, but the CNC itself usually does not give any inherent speed advantage within the context of an automatic lathe cycle in terms of speeds and feeds or tool-changing speed. There are many variables involved in answering the question of which is best for a particular part at a particular company. (Overhead is part of the calculation—not least because most cam-op machines are long since paid for, whereas a late-model CNC machine has hefty monthly payments). Businesses relying on cam-op machines are still competing even in today's CNC-filled environment; they just need to be vigilant and smart about keeping it that way.\nIn the multispindle segment, some machine tool builders also build hybrid machines that are part CNC and part old-school control (some stations are CNC while others are cam-op or actuated with simple hydraulic cycles). This lets shops with certain mixes of work derive competitive advantage from the lower cost compared with all-CNC machines. The variety of machines that allow profitable production within certain niches reflects the variety of work that exists: some high-volume work remains the province of cam-op; full CNC with all the bells and whistles outcompetes on some flexible low-volume work; and hybrid machines may yield the lowest unit price on mixes in between.\nDesign.\nAn automatic lathe may have a single spindle or multiple spindles. Each spindle contains a bar or blank of material that is being machined simultaneously. A common configuration is six spindles. The cage that holds these six bars of material indexes after each machining operation is complete. The indexing is reminiscent of a Gatling gun.\nEach station may have multiple tools that cut the material in sequence. The tools are usually arranged in several axes, such as turret (rotary indexing), horizontal slide (linear indexing), and vertical slide (linear indexing). The linear groups are called \"gangs\". The operation of all these tools is similar to that on a turret lathe.\nBy way of example: a bar of material is fed forward through the spindle. The face of the bar is machined (facing operation). The outside of the bar is machined to shape (turning operation). The bar is drilled or bored, and finally, the part is cut off (parting operation).\nIn a single-spindle machine, these four operations would most likely be performed sequentially, with four cross-slides each coming into position in turn to perform their operation. In a multi-spindle machine, each station corresponds to a stage in the production sequence through which each piece is then cycled, all operations occurring simultaneously, but on different pieces of work, in the manner of an assembly line.\nOperations.\nForm tools.\nFor the machining of complex shapes, it is common to use form tools. This contrasts with the cutting that is performed on an engine lathe where the cutting tool is usually a single-point tool. A form tool has the form or contour of the final part but in reverse, so it cuts the material leaving the desired component shape. This contrasts to a single-point tool, which cuts on one point at a time and the shape of the component is dictated by the motion of the tool rather than its shape.\nThreading.\nUnlike on a lathe, single-point threading is rarely if ever performed; it is too time-consuming for the short cycle times that are typical of screw machines. A self-releasing die head can rapidly cut or roll-form threads on outside diameters. A non-releasing tap holder with a tap can quickly cut inside diameters but it requires single spindle machines to reverse into high speed in order for the tap to be removed from the work. Threading and tapping speed (low speed) is typically 1/5 the high speed.\nRotary broaching.\nRotary broaching is another common operation. The broach holder is mounted stationary while its internal live spindle and end cutting broach tool are driven by the workpiece. As the broach is fed into or around the workpiece, the broach's contact points are constantly changing, easily creating the desired form. The most common form made this way is a hexagonal socket in the end of a cap screw.\nHistory.\nThe history of automatic lathes in industrial contexts began with screw machines, and that history can only be truly understood within the context of screw making in general. Thus the discussion below begins with a simple overview of screw making in prior centuries, and how it evolved into 19th-, 20th-, and 21st-century practice.\nHumans have been making screws since ancient times. For most of those centuries, screw making generally involved custom cutting of the threads of each screw by hand (via whittling or filing). Other ancient methods involved wrapping wire around a mandrel (such as a stick or metal rod) or carving a tree branch that had been spirally wrapped by a vine.\nVarious machine elements that potentially lent themselves to screw making (such as the lathe, the leadscrew, the slide rest, gears, slide rests geared direct to spindles, and \"change gear\" gear trains) were developed over the centuries, with some of those elements being quite ancient. Various sparks of inventive power during the Middle Ages and Renaissance combined some of these elements into screw-making machines that presaged the industrial era to follow. For example, various medieval inventors whose names are lost to history clearly worked on the problem, as shown by Wolfegg Castle's \"Medieval Housebook\" (written circa 1475–1490), and Leonardo da Vinci and Jacques Besson left us with drawings of screw-cutting machines from the 1500s; not all of these designs are known to have been built, but clearly similar machines were a reality during Besson's lifetime. However, it was not until 1760–1800 that these various elements were brought together successfully to create (in contemporaneous parallel) two new types of machine tool: the screw-cutting lathe (for low-volume, toolroom-style production of \"machine\" screws, with easy selection of various pitches) and the first high-volume-production, specialized, single-purpose machine tools for the production of screws, which were created to produce \"wood\" screws [meaning screws made of metal for use in wood] at high volume and low unit price. Screw-cutting lathes fed into the just-dawning evolution of modern machine shop practice, whereas the wood-screw-making machines fed into the just-dawning evolution of the modern hardware industry, that is, the concept of one factory supplying the needs of thousands of customers, who consumed screws in growing quantities for carpentry, cabinet making, and other trades, but did not make the hardware themselves (purchasing it instead from capital-intensive specialist makers for lower unit cost than they could achieve on their own). These two classes of machine tools simultaneously took the various classes of screws and moved them, for the first time, from the category of expensive, hand-made, seldom-used objects into the category of affordable, often-interchangeable commodity. (The interchangeability developed gradually, from intra-company to inter-company to national to international).\nBetween 1800 and 1840, on the machine-screw side, it became common practice to build all of the relevant screw-cutting machine elements into engine lathes, so the term \"screw-cutting lathe\" ceased to stand in contradistinction to other metalworking lathe types as a \"special\" kind of lathe. Meanwhile, on the wood-screw side, hardware manufacturers had developed for their own in-house use the first fully automatic [mechanically automated] special-purpose machine tools for the making of screws. The 1760–1840 development arc was a tremendous technological advance, but later advancements would make screws even cheaper and more prevalent yet again. These began in the 1840s with the adaptation of the engine lathe with a turret-head toolholder to create the turret lathe. This development greatly reduced the time, effort, and skill needed from the machine operator to produce each machine screw. Single-pointing was forgone in favor of die head cutting for such medium- and high-volume repetitive production. Then, in the 1870s, the turret lathe's part-cutting cycle (sequence of movements) was automated by being put under cam control, in a way very similar to how music boxes and player pianos can play a tune automatically. According to Rolt (1965), the first person to develop such a machine was Christopher Miner Spencer, a New England inventor. may have contemporarily independently invented a machine similar to Spencer's. However, the wood-screw-making machines of the 1840s and 1850s [special-purpose factory production machine tools as opposed to small-machine-shop machine tools], such as those developed by Cullen Whipple of the New England Screw Company and Thomas J. Sloan of the American Screw Company, had anticipated the machines of Spencer and Vander Woerd in various ways, albeit approaching the problem of automated screw production from a different commercial angle. All of the above machine tools (i.e., screw-cutting lathes; suitably equipped engine lathes and bench lathes; turret lathes; turret-lathe-derived screw machines; and wood-screw-factory screw machines) were sometimes called \"screw machines\" during this era (logically enough, given that they were machines tailored to screw making). The nomenclatural evolution whereby the term \"screw machine\" is often used more narrowly than that is discussed above.\nSpencer patented his idea in 1873; but his patent failed to protect the cam drum, which Spencer called the 'brain wheel'. Therefore, many other people quickly took up the idea. Later important developers of fully automatic lathes included S. L. Worsley, who developed a single-spindle machine for Brown & Sharpe, Edwin C. Henn, Reinhold Hakewessel, and George O. Gridley, who developed multiple-spindle variants and who was involved with a succession of corporations (Acme, National, National-Acme, Windsor Machine Company, Acme-Gridley, New Britain-Gridley); Edward P. Bullard Jr, who led the development of the Bullard Mult-Au-Matic; F.C. Fay and Otto A. Schaum, who developed the Fay automatic lathe; Ralph Flanders and his brother Ernest, who further refined the Fay lathe and developed the automatic screw thread grinder. Meanwhile, engineers in Switzerland were also developing new manually and automatically controlled lathes. The technological developments in America and Switzerland flowed rapidly into other industrialized countries (via routes such as machine tool exports; trade journal articles and advertisements; trade shows, from world's fairs to regional events; and the turnover and emigration of engineers, setup hands, and operators). There, local innovators also developed further tooling for the machines and built clone machine models.\nThe development of numerical control was the next major leap in the history of automatic lathes—and it is also what changed the paradigm of what the \"manual versus automatic\" distinction meant. Beginning in the 1950s, NC lathes began to replace manual lathes and cam-op screw machines, although the displacement of the older technology by CNC has been a long, gradual arc that even today is not a total eclipse. By the 1980s, true CNC screw machines (as opposed to simpler CNC lathes), Swiss-style and non-Swiss, had begun to make serious inroads into the realm of cam-op screw machines. Similarly, CNC chuckers were developed, eventually evolving even into CNC rotary transfer machines. These machine tools are little known outside the automotive manufacturing sector.", "Engineering,_Manufacturing": 0.9999990463, "qwen": "Yes"}
{"id": "42202124", "revid": "41807748", "url": "https://en.wikipedia.org/wiki?curid=42202124", "title": "Euro container", "text": "A Euro container, also called Eurobox, Euro crate or KLT box (from , \"small load carrier\"), is an industrial stacking container conforming to the VDA 4500 standard. The standard was originally defined by the German Association of the Automotive Industry (VDA) for the automotive industry, but was subsequently adopted across many other areas of manufacturing and the shipping industry. The most common sizes (length × width) are 600 × 400 mm and 400 × 300 mm, which can be stacked together to fill a Euro-pallet measuring 1200 × 800 mm.\nDimensions.\nEurocontainers are based around two standard heights of and , including a overlap in the vertical direction—the height of the feet, or base, stacked into the lip of the box below:\nThese containers are manufactured typically in grey polypropylene or another thermoplast by injection molding.\nContainers with full floor and walls are watertight. Many designs have at least two or more often four rectangular (about 12 x 4 cm) rounded grip-holes near the middle of the lips. The design may include some small holes in the lowest parts of at least two walls to let liquid run out if stored outdoors in rain or after washing. Walls constructed as grids allow one to see from the side into the box. If the bottom is formed by a grid, too, air may flow easily through even stacked boxes to keep bakery dry or allow quick cooling.\nEuro-containers mounted on the rear rack of a bicycle or small motorcycle are widely used by newspaper-deliverers in Austrian towns. A Euro-container fits between the frame tubes in the low transportation bay of the Danish freight bike Bullitt.\nRelated standards.\nThe 400×300-millimetre sizes and stacking height were adopted in the early 1990s for inter-stacking Systainer boxes.", "Engineering,_Manufacturing": 1.000009656, "qwen": "Yes"}
{"id": "15714224", "revid": "5846", "url": "https://en.wikipedia.org/wiki?curid=15714224", "title": "Perforated metal", "text": "Perforated metal, also known as perforated sheet, perforated plate, or perforated screen, is sheet metal that has been manually or mechanically stamped or punched using CNC technology or in some cases laser cutting to create different holes sizes, shapes and patterns. Materials used to manufacture perforated metal sheets include stainless steel, cold rolled steel, galvanized steel, brass, aluminum, tinplate, copper, Monel, Inconel, titanium, plastic, and more.\nThe process of perforating metal sheets has been practiced for over 150 years. In the late 19th century, metal screens were used as an efficient means of separating coal. The first perforators were laborers who would manually punch individual holes into the metal sheet. This proved to be an inefficient and inconsistent method which led to the development of new techniques, such as perforating the metal with a series of needles arranged in a way that would create the desired hole pattern.\nModern day perforation methods involve the use of technology and machines. Common equipment used for the perforation of metal include rotary pinned perforation rollers, die and punch presses, and laser perforations.\nApplications.\nPerforated metal has been utilized across a variety of industries including, but not limited to:\nBenefits.\nThe acoustic performance of perforated metal helps people or workers to limit health effects from noise. Studies have shown that perforated metals help reduce sound levels.\nStudies have shown that having buildings use perforated metal sheets in front of their façade can bring in one study 29% energy savings (HVAC + Lighting estimated consumption in 1 year) and in the second one 45% energy savings (heating, ventilation, air conditioning). Depending on the location of the building (intensity of the external sun), solar irradiation can be decrease by 77.9%.", "Engineering,_Manufacturing": 0.9994021654, "qwen": "Yes"}
{"id": "15731156", "revid": "41167035", "url": "https://en.wikipedia.org/wiki?curid=15731156", "title": "FEM Element", "text": "FEM Element is a commercial finite element method solver for electromagnetic structures from EEsof. FEM Element can perform electromagnetic simulation of arbitrarily-shaped, passive three-dimensional structures.\nIt is aimed at providing 3D EM simulation to designers working on RF circuits, MMICs, PC boards, modules, and signal integrity applications. It provides a full 3D electromagnetic field solver, a solid modeling GUI, and fully automated meshing and convergence capabilities for modeling arbitrary 3D shapes such as connectors, machined parts, components, bond wires, antennas, and packages.\nFEM Element is available with integration into Keysight EEsof's Advanced Design System (ADS) and EMPro platforms.\nIt was originally called Electromagnetic Design System (EMDS).", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "5800369", "revid": "39517085", "url": "https://en.wikipedia.org/wiki?curid=5800369", "title": "2003 UEFA Intertoto Cup", "text": "The 2003 UEFA Intertoto Cup finals were won by Schalke 04, Villarreal, and Perugia. All three teams advanced to the UEFA Cup.\nFirst round.\nFirst leg.\n\"This game was declared void by UEFA due to fan incident at the stadium with smoke bomb thrown onto the field. The second leg game by itself determined the result of the matchup.\"\nSecond leg.\n\"2–2 on aggregate, Pasching won on away goals rule.\"\n\"Lierse won 7–1 on aggregate.\"\n\"Pobeda won 7–2 on aggregate.\"\n\"3–3 on aggregate, Partizani won on away goals rule.\"\n\"3–3 on aggregate, Brno won on away goals rule.\"\n\"Koper won 3–2 on aggregate.\"\n\"Örgryte IS won 4–1 on aggregate.\"\n\"3–3 on aggregate, Győr won on away goals rule.\"\n\"Marek Dupnitsa won 5–4 on aggregate.\"\n\"Shamrock Rovers won 3–1 on aggregate.\"\n\"2–2 on aggregate, Tampere United won on away goals rule.\"\n\"Sutjeska won 4–1 on aggregate.\"\n\"Gloria Bistrița won 6–2 on aggregate.\"\n\"OFK Beograd won 5–3 on aggregate.\"\n\"Wil won 2–1 on aggregate.\"\n\"Tobol won 5–1 on aggregate.\"\n\"ZTS Dubnica won 7–1 on aggregate.\"\n\"Dacia Chișinău won 5–1 on aggregate.\"\n\"2–2 on aggregate, Sloboda Tuzla won on penalties.\"\n\"Shakhtyor Soligorsk won 8–1 on aggregate.\"\n\"Allianssi won 2–1 on aggregate.\"\nSecond round.\nSecond leg.\n\"Allianssi won 1–0 on aggregate.\"\n\"4–4 on aggregate, Nice won on away goals rule.\"\n\"Slovácko won 4–3 on aggregate.\"\n\"2–2 on aggregate, Racing de Santander won on away goals rule.\"\n\"Slovan Liberec won 4–0 on aggregate.\"\n\"Brno won 4–3 on aggregate.\"\n\"Brescia won 3–2 on aggregate.\"\n\"Wolfsburg won 3–1 on aggregate.\"\n\"Cibalia won 5–3 on aggregate.\"\n\"Tobol won 3–0 on aggregate.\"\n\"Wil won 4–3 on aggregate.\"\n\"Pasching won 3–2 on aggregate.\"\n\"Lierse won 5–2 on aggregate.\"\n\"Tampere United won 1–0 on aggregate.\"\n\"Dacia Chișinău won 5–0 on aggregate.\"\n\"3–3 on aggregate, Koper won on away goals rule.\"\nThird round.\nSecond leg.\n\"Pasching won 4–0 on aggregate.\"\n\"Perugia won 4–0 on aggregate.\"\n\"Koper won 5–4 on aggregate.\"\n\"Nantes won 5–3 on aggregate.\"\n\"Werder Bremen won 1–0 on aggregate.\"\n\"Villarreal won 3–1 on aggregate.\"\n\"Brno won 5–4 on aggregate.\"\n\"Schalke 04 won 3–1 on aggregate.\"\n\"Slovan Liberec won 3–1 on aggregate.\"\n\"Wolfsburg won 3–0 on aggregate.\"\n\"Cibalia won 2–1 on aggregate.\"\n\"Heerenveen won 5–1 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Heerenveen won 2–1 on aggregate.\"\n\"Wolfsburg won 8–1 on aggregate.\"\n\"Schalke 04 won 2–1 on aggregate.\"\n\"Pasching won 5–1 on aggregate.\"\n\"Perugia won 1–0 on aggregate.\"\n\"Villarreal won 3–1 on aggregate.\"\nFinals.\nSecond leg.\n\"Schalke 04 won 2–0 on aggregate.\"\n\"Perugia won 3–0 on aggregate.\"\n\"Villareal won 2–1 on aggregate.\"", "Engineering,_Manufacturing": 1.0000047684, "qwen": "Yes"}
{"id": "1594030", "revid": "1139934443", "url": "https://en.wikipedia.org/wiki?curid=1594030", "title": "Moisture sensitivity level", "text": "Moisture sensitivity level (MSL) is a rating that shows a device's susceptibility to damage due to absorbed moisture when subjected to reflow soldering as defined in J-STD-020.\nIt relates to the packaging and handling precautions for some semiconductors. The MSL is an electronic standard for the time period in which a moisture sensitive device can be exposed to ambient room conditions (30 °C/85%RH at Level 1; 30 °C/60%RH at all other levels).\nIncreasingly, semiconductors have been manufactured in smaller sizes. Components such as thin fine-pitch devices and ball grid arrays could be damaged during SMT reflow when moisture trapped inside the component expands.\nThe expansion of trapped moisture can result in internal separation (delamination) of the plastic from the die or lead-frame, wire bond damage, die damage, and internal cracks. Most of this damage is not visible on the component surface. In extreme cases, cracks will extend to the component surface. In the most severe cases, the component will bulge and pop. This is known as the \"popcorn\" effect. This occurs when part temperature rises rapidly to a high maximum during the soldering (assembly) process. This does not occur when part temperature rises slowly and to a low maximum during a baking (preheating) process.\nMoisture sensitive devices are packaged in a moisture barrier antistatic bag with a desiccant and a moisture indicator card which is sealed.\nMoisture sensitivity levels are specified in technical standard IPC/JEDEC \"Moisture/reflow Sensitivity Classification for Nonhermetic Surface-Mount Devices\". The times indicate how long components can be outside of dry storage before they have to be baked to remove any absorbed moisture.\nPractical.\nMSL-specified parts must be baked before assembly if their exposure has exceeded the rating. Once assembled, moisture sensitivity is generally no longer a factor.\nExternal links.\nhttps://www.ipc.org/TOC/IPC-JEDEC-J-STD-020E.pdf\nhttps://www.bourns.com/docs/RoHS-MSL/msl_mf.pdf", "Engineering,_Manufacturing": 0.9995498657, "qwen": "Yes"}
{"id": "66038122", "revid": "43232617", "url": "https://en.wikipedia.org/wiki?curid=66038122", "title": "High performance positioning system", "text": "A high performance positioning system (HPPS) is a type of positioning system consisting of a piece of electromechanics equipment (e.g. an assembly of linear stages and rotary stages) that is capable of moving an object in a three-dimensional space within a work envelope. Positioning could be done point to point or along a desired path of motion. Position is typically defined in six degrees of freedom, including linear, in an x,y,z cartesian coordinate system, and angular orientation of yaw, pitch, roll. HPPS are used in many manufacturing processes to move an object (tool or part) smoothly and accurately in six degrees of freedom, along a desired path, at a desired orientation, with high acceleration, high deceleration, high velocity and low settling time. It is designed to quickly stop its motion and accurately place the moving object at its desired final position and orientation with minimal jittering.\nHPPS requires a structural characteristics of low moving mass and high stiffness. The resulting system characteristic is a high value for the lowest natural frequency of the system. High natural frequency allows the motion controller to drive the system at high servo bandwidth, which means that the HPPS can reject all motion disturbing frequencies, which act at a lower frequency than the bandwidth. For higher frequency disturbances such as floor vibration, acoustic noise, motor cogging, bearing jitter and cable carrier rattling, HPPS may employ structural composite materials for damping and isolation mounts for vibration attenuation. Unlike articulating robots, which have revolute joints that connect their links, HPPS links typically consists of sliding joints, which are relatively stiffer than revolute joints. That is the reason why high performance positioning systems are often referred to as cartesian robots. \nPerformance.\nHPPS, driven by linear motors, can move at a combined high velocity on order of 3-5 m/s, high accelerations of 5-7 g, at micron or sub micron positioning accuracy with settling times on order of milliseconds and servo bandwidth of 30-50 Hz. Ball screw actuators, on the other hand, have typical bandwidth of 10-20 Hz and belt driven actuators at about 5-10 Hz. The bandwidth value of HPPS is about 1/3 of the lowest natural frequency in the range of 90-150 Hz. Settling time to +/- 1% Constant Velocity, or + / - 1 um jitter, after high acceleration or high deceleration respectively, takes an estimated 3 bandwidth periods. For example, a 50 Hz servo bandwidth, having a 1 / 50 · 1000 = 20 msec period, will settle to 1 um position accuracy within an estimated 3 · 20 = 60 msec. The lowest natural frequency equals the square root of system stiffness divided by moving inertia. A typical linear recirculating bearing rail, of a high performance positioning stage, has a stiffness on order of 100-300 N/um. Such a performance is required in semiconductor process equipment, electronics assembly lines, numerically controlled machine tools, coordinate-measuring machines, 3D Printing, pick-and-place machines, drug discovery assaying and many more. At their highest performance HPPS may use granite base for thermal stability and flat surfaces, air bearings for jitter free motion, brushless linear motors for non contact, frictionless actuation, high force and low inertia, and laser interferometer for sub micron position feedback. On the other hand, a typical 6 degrees of freedom articulated robot, with 1 m' reach, has a structural stiffness on the order of 1 N/um. That is why articulated robots are best being employed as automation equipment in processes which require position repeatability on the order of 100's microns, such as robot welding, paint robots, palletizers and many more. \nHistory.\nThe original HPPS were developed at Anorad Corporation (now Rockwell Automation) in the 1980s, after the invention of brushless linear motors by Anorad's Founder and CEO, Anwar Chitayat. Initially HPPS were used for high precision manufacturing processes in semiconductor applications such as Applied Materials, PCB Inspection Orbotech and High Velocity Machine Tool Ford. In parallel linear motor technology and their integration in HPPS, was expanded around the world. As a result, in 1996 Siemens integrated its CNC with Anorad linear motors to drive a 20 m' long Maskant machine at Boeing for chemical milling of aircraft wings. In 1997 FANUC licensed Anorad's linear motor technology and integrated it as a complete solution with their CNC products line. And in 1998, Rockwell Automation acquired Anorad to compete with Siemens and Fanuc in providing a complete linear motor solutions to drive high velocity machine tools in Automotive transfer lines. Today linear motors are being used in hundreds of thousands high performance positioning systems, which drive manufacturing processes around the world. Their market is expected to grow, according to some studies, at 4.4% a year and reach $1.5B in 2025. \nSystem requirements.\nSpecifications.\nSystem specification (technical standard) is an official interface between the application requirements (problem), as described by the user (customer) and the design (solution) as optimized by the developer (supplier). \nSystem solution.\nConfiguration.\nHPPS configuration is typically optimized for maximum structural stiffness with maximum damping and minimum inertia, smallest Abbe error at the point of interest (POI), with minimum components and maximum maintainability.\nSystem analysis.\nSystem analysis is a process of understanding the relationships between design parameters, operating conditions, environmental variables and system performance based on system modeling and analysis tools\nComponent sizing.\nComponent sizing is the process of selecting standard parts from component suppliers, or designing a custom part for manufacturing \nSystem testing.\nSystem testing is an iterative process of system development, intended to validate system analysis modeling, proof of concepts, safety factor of performance specifications and acceptant testing.", "Engineering,_Manufacturing": 1.0000070333, "qwen": "Yes"}
{"id": "5165628", "revid": "42425010", "url": "https://en.wikipedia.org/wiki?curid=5165628", "title": "Production board", "text": "A traditional production board, stripboard, or production strip is a filmmaking term for a cardboard or wooden chart displaying color-coded strips of paper, each containing information about a scene in the film's shooting script. The strips can then be rearranged and laid out sequentially to represent the order one wants to film in, providing a schedule that can be used to plan the production. This is done because most films are shot \"out of sequence,\" meaning that they do not necessarily begin with the first scene and end with the last. For logistical purposes, scenes are often grouped by talent or location and are arranged to accommodate the schedules of cast and crew. A production board is not to be confused with a Stripboard used for electronics prototyping.\nA modern version of a strip board will commonly be printed using dedicated computer software, such as MovieMagic Scheduling, Celtx, or Scenechronize, or by customizing general purpose software such as OpenOffice.org Calc or Microsoft Excel.\nCommon Contents.\nInformation on the strips can include\nColor Conventions.\nProduction strip boards are often color-coded according to the following convention:\nScenechronize uses a sightly modified convention:\nFinally, MovieMagic Scheduling has its own standard:", "Engineering,_Manufacturing": 0.999794662, "qwen": "Yes"}
{"id": "5167489", "revid": "21436738", "url": "https://en.wikipedia.org/wiki?curid=5167489", "title": "Flexible manufacturing system", "text": "A flexible manufacturing system (FMS) is a manufacturing system in which there is some amount of flexibility that allows the system to react in case of changes, whether predicted or unpredicted. \nThis flexibility is generally considered to fall into two categories, which both contain numerous subcategories.\nMost flexible manufacturing systems consist of three main systems:\nThe main advantages of a flexible manufacturing system is its high flexibility in managing manufacturing resources like time and effort in order to manufacture a new product.\nThe best application of a flexible manufacturing system is found in the 'production of small sets of products like those from a mass production.\nFlexibility.\nFlexibility in manufacturing means the ability to deal with slightly or greatly mixed parts, to allow variation in parts assembly and variations in process sequence, change the production volume and change the design of certain product being manufactured.\nIndustrial FMS communication.\nAn industrial flexible manufacturing system consists of robots, computer-controlled Machines, computer numerical controlled machines (CNC), instrumentation devices, computers, sensors, and other stand alone systems such as inspection machines. The use of robots in the production segment of manufacturing industries promises a variety of benefits ranging from high utilization to high volume of productivity. Each Robotic cell or node will be located along a material handling system such as a conveyor or automatic guided vehicle. The production of each part or work-piece will require a different combination of manufacturing nodes. The movement of parts from one node to another is done through the material handling system. At the end of part processing, the finished parts will be routed to an automatic inspection node, and subsequently unloaded from the Flexible Manufacturing System.\nThe FMS data traffic consists of large files and short messages, and mostly come from nodes, devices and instruments. The message size ranges between a few bytes to several hundreds of bytes. Executive software and other data, for example, are files with a large size, while messages for machining data, instrument to instrument communications, status monitoring, and data reporting are transmitted in small size.\nThere is also some variation on response time. Large program files from a main computer usually take about 60 seconds to be down loaded into each instrument or node at the beginning of FMS operation. Messages for instrument data need to be sent in a periodic time with deterministic time delay. Other types of messages used for emergency reporting are quite short in size and must be transmitted and received with an almost instantaneous response.\nThe demands for reliable FMS protocol that support all the FMS data characteristics are now urgent. The existing IEEE standard protocols do not fully satisfy the real time communication requirements in this environment. The delay of CSMA/CD is unbounded as the number of nodes increases due to the message collisions. Token bus has a deterministic message delay, but it does not support prioritized access scheme which is needed in FMS communications. Token Ring provides prioritized access and has a low message delay, however, its data transmission is unreliable. A single node failure which may occur quite often in FMS causes transmission errors of passing message in that node. In addition, the topology of Token Ring results in high wiring installation and cost.\nA design of FMS communication that supports a real time communication with bounded message delay and reacts promptly to any emergency signal is needed. Because of machine failure and malfunction due to heat, dust, and electromagnetic interference is common, a prioritized mechanism and immediate transmission of emergency messages are needed so that a suitable recovery procedure can be applied. A modification of standard Token Bus to implement a prioritized access scheme was proposed to allow transmission of short and periodic messages with a low delay compared to the one for long messages.", "Engineering,_Manufacturing": 1.0000082254, "qwen": "Yes"}
{"id": "39973757", "revid": "868070483", "url": "https://en.wikipedia.org/wiki?curid=39973757", "title": "Soft retooling", "text": "Soft retooling is a process that changes the ablation shape during laser ablation without changing any hardware. Contrarily to conventional milling, it is possible with laser sculpting to change ablation geometry just by changing parameters of laser ablation that have the desired effects on laser ablation. Conventional milling machines contain trays on which different tool bits are stored and must consider in their machining routine tool change. This operation is not necessary when using laser sculpting. ", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "47207645", "revid": "211905", "url": "https://en.wikipedia.org/wiki?curid=47207645", "title": "Coupon (PWB)", "text": "A coupon or test coupon is a printed circuit board (PCB) used to test the quality of a printed wiring board (PWB) fabrication process. Test coupons are fabricated on the same panel as the PWBs, typically at the edges. Coupons are then inspected to ensure proper layer alignment, electrical connectivity, and cross sectioned to inspect internal structures. Coupons can be designed custom for a PWB or selected from a vendor library.\nOverview.\nA coupon is designed to include traces and vias with the same dimensions and structures as those of the main PWB. It is standard practice to locate coupons on the edges of a panel, from which multiple PWBs are fabricated, to verify the consistency of plating, etching, and lamination across the whole panel. The use of coupons for testing is a necessary step in accurately and reliably monitoring fabrication quality and consistency.", "Engineering,_Manufacturing": 1.0000097752, "qwen": "Yes"}
{"id": "47224369", "revid": "42425010", "url": "https://en.wikipedia.org/wiki?curid=47224369", "title": "Moody Fabrication & Machine, Inc.", "text": "Moody Fabrication & Machine, Inc. was a subsidiary of M. D. Moody & Sons, Inc. that manufactured parts for heavy machinery equipment as well as operated barges for the transport of marine and construction equipment. It was located at the Bellinger Shipyard on the Intracoastal Waterway between Jacksonville and Atlantic Beach. In October 2014, M. D. Moody & Sons, Inc. sold the Bellinger Shipyard to Jacksonville Intracoastal, LLC. for $9.4 million.\nOperations.\nMoody Fabrication & Machine, Inc. operated out of the headquarters of M. D. Moody & Sons, Inc. in 1994 fabricating sheet metal and manufacturing parts for heavy machinery. In February 1995 a shipyard on the Intracoastal Waterway called the Bellinger Shipyard was sold to M. D. Moody & Sons, Inc. for $1.9 million by Fruehauf Trailer Corporation. Moody Fabrication & Machine moved to the newly purchased Bellinger Shipyard where it operated for 19 years. The main operations of Moody Fabrication is its crane boom shop, fabrication shop, and its machine shop. The crane boom shop builds and repairs crane booms for various crane manufacturers. Employees of Moody Fabrication are certified welders who perform repairs, machine work, and millwright work. The Bellinger Shipyard was also shared with MOBRO Marine, Inc. Moody Fabrication & Machine utilized the Intracoastal to transport completed products such as tugboats and heavy equipment.\nDecline.\nDuring the Great Recession in March 2010 Moody Fabrication & Machine declined in business. At the same time M. D. Moody & Sons, Inc. had filed for Chapter 11 Banktruptcy putting the fate of Moody Fabrication & Machine in jeopardy. Because of a decline in business M. D. Moody decided to sell the Bellinger Shipyard and gradually cease operations of Moody Fabrication & Machine. In October 2014 M. D. Moody sold the Bellinger Shipyard to Jacksonville Intracoastal LLC. for $9.4 million.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "6033807", "revid": "35498457", "url": "https://en.wikipedia.org/wiki?curid=6033807", "title": "List of manufacturers by motor vehicle production", "text": "This is a list of manufacturers by motor vehicle production, by year, based on Organisation Internationale des Constructeurs d'Automobiles (OICA).\nFigures include passenger cars, light commercial vehicles, minibuses, trucks, buses and coaches. OICA defines these entries as follows:\nOverview.\nMotor vehicle production by manufacturer (top five groups)\nThe summary chart includes the five largest worldwide automotive manufacturing groups as of 2017 by number of vehicles produced. Those same groups have held the top 5 positions since 2007; only Hyundai / Kia had a lower rank until it took the fifth spot from DaimlerChrysler in 2006. Figures were compiled by the International Organization of Motor Vehicle Manufacturers (OICA):\n2000, \n2001, \n2002, \n2003, \n2004, \n2005, \n2006, \n2007, \n2008, \n2009, \n2010, \n2011, \n2012, \n2013, \n2014, \n2015,\n2016,\n2017.\n2017.\nThis is a list of largest manufacturers by production in 2017.\n2016.\nThis is a list of largest manufacturers by production in 2016. Some figures were amended in the 2017 report.\n2015.\nRank of manufacturers by production in 2015\n2014.\nRank of manufacturers by production in 2014\n2013.\nRank of manufacturers by production in 2013\n2012.\nRank of manufacturers by production in 2012\n2008.\nThis is a list of the 20 largest automotive manufacturers, ranked by their production volume in 2008.\n2007.\nThis is a list of the 20 largest automotive manufacturers, ranked by their production volume in 2007.\n2006.\nThis is a list of the 20 largest automotive manufacturers, ranked by their production volume in 2006.\n2005.\nThis is a list of the 20 largest automotive manufacturers, ranked by their production volume in 2005.\n2004.\nThis is a list of the 20 largest automotive manufacturers, ranked by their production volume in 2004.", "Engineering,_Manufacturing": 0.9980238676, "qwen": "Yes"}
{"id": "7327033", "revid": "1189543", "url": "https://en.wikipedia.org/wiki?curid=7327033", "title": "Charles L. Coffin", "text": "Charles L. Coffin of Detroit was awarded for an arc welding process using a metal electrode. This was the first time that metal melted from the electrode carried across the arc to deposit filler metal in the joint to make a weld. Two years earlier, Nikolay Slavyanov presented the same idea of transferring metal across an arc, but to cast metal in a mold.", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "7338721", "revid": "1086105321", "url": "https://en.wikipedia.org/wiki?curid=7338721", "title": "Thermal relief", "text": "A thermal relief pad, thermal pad or simply thermal, is a printed circuit board (PCB) pad connected to a copper pour using a \"thermal connection\". It looks like a normal pad with copper \"spokes\" connecting it to the surrounding copper.\nA typical pad on a printed circuit board is only connected to a few narrow tracks. A pad directly connected to the copper pour is difficult to solder, since the heat quickly leaks away from the pad into the copper pour due to high thermal conductivity of copper. A thermal connection restricts the heat flow, making the pad easier to solder.\nVia holes that only connect one layer to another, without having soldering wires or pins into the hole, do not normally need thermal restriction.\nWire-leaded components may require the thermal relief pattern to be customized or even omitted when carrying radio-frequency currents (where the additional inductance would be problematic), or where very high current densities are expected (where the spokes of the thermal relief may act as a fuse). In these cases the parts may require additional hand soldering during assembly. ", "Engineering,_Manufacturing": 1.0000098944, "qwen": "Yes"}
{"id": "5903973", "revid": "910180", "url": "https://en.wikipedia.org/wiki?curid=5903973", "title": "Record press", "text": "A record press is a machine for manufacturing vinyl records. It is essentially a hydraulic press fitted with thin nickel stampers which are negative impressions of a master disc. Labels and a pre-heated vinyl patty (or \"biscuit\") are placed in a heated mold cavity. Two stampers are used, one for each of side of the disc. The record press closes under a pressure of about 150 tons. The process of compression molding forces the hot vinyl to fill the grooves in the stampers, and take the form of the finished record.\nVacuum molding.\nIn the mid-1960s, Emory Cook developed a system of record forming wherein the mold pressure was replaced by a vacuum. In this technique, the mold cavity was evacuated and vinyl was introduced in micro-particle form. The particles were then flash-fused instantaneously at a high temperature forming a coherent solid. Cook called this disc manufacturing technology \"microfusion\". A small pressing plant in Hollywood also employed a similar system which they maintained fused the particles more evenly throughout the disc thickness calling their product \"polymax\". Both claimed the resultant disc grooves exhibited less surface noise and greater resistance to deformation from stylus tip inertia than convention pressure molded vinyl discs. ", "Engineering,_Manufacturing": 0.9999898672, "qwen": "Yes"}
{"id": "241688", "revid": "1150511979", "url": "https://en.wikipedia.org/wiki?curid=241688", "title": "Submerged arc welding", "text": "Submerged arc welding (SAW) is a common arc welding process. The first SAW patent was taken out in 1935. The process requires a continuously fed consumable solid or tubular (metal cored) electrode. The molten weld and the arc zone are protected from atmospheric contamination by being \"submerged\" under a blanket of granular fusible flux consisting of lime, silica, manganese oxide, calcium fluoride, and other compounds. When molten, the flux becomes conductive, and provides a current path between the electrode and the work. This thick layer of flux completely covers the molten metal thus preventing spatter and sparks as well as suppressing the intense ultraviolet radiation and fumes that are a part of the shielded metal arc welding (SMAW) process.\nSAW is normally operated in the automatic or mechanized mode, however, semi-automatic (hand-held) SAW guns with pressurized or gravity flux feed delivery are available. The process is normally limited to the flat or horizontal-fillet welding positions (although horizontal groove position welds have been done with a special arrangement to support the flux). Deposition rates approaching 45 kg/h (100 lb/h) have been reported — this compares to ~5 kg/h (10 lb/h) (max) for shielded metal arc welding. Although currents ranging from 300 to 2000 A are commonly utilized, currents of up to 5000 A have also been used (multiple arcs).\nSingle or multiple (2 to 5) electrode wire variations of the process exist. SAW strip-cladding utilizes a flat strip electrode (e.g. 60 mm wide x 0.5 mm thick). DC or AC power can be used, and combinations of DC and AC are common on multiple electrode systems. Constant voltage welding power supplies are most commonly used; however, constant current systems in combination with a voltage sensing wire-feeder are available.\nFeatures.\nWelding head.\nIt feeds flux and filler metal to the welding joint. The electrode (filler metal) gets energized here.\nFlux hopper.\nIt stores the flux and controls the rate of flux deposition on the welding joint.\nFlux.\nThe granulated flux shields and thus protects molten weld from atmospheric contamination. The flux cleans weld metal and can also modify its chemical composition. The flux is granulated to a definite size. It may be of fused, bonded or mechanically mixed type. The flux may consist of fluorides of calcium and oxides of calcium, magnesium, silicon, aluminium and manganese compounds. Alloying elements may be added as per requirements. Substances involving large amounts of gas during welding are never mixed with the flux. Flux with fine and coarse particle sizes are recommended for welding heavier and smaller thickness respectively.\nElectrode.\nSAW filler material usually is a standard wire as well as other special forms. This wire normally has a thickness of 1.6 mm to 6 mm (1/16 in. to 1/4 in.). In certain circumstances, twisted wire can be used to give the arc an oscillating movement. This helps fuse the toe of the weld to the base metal.\nThe electrode composition depends upon the material being welded. Alloying elements may be added in the electrodes. Electrodes are available to weld mild steels, high carbon steels, low and special alloy steels, stainless steel and some of the nonferrous of copper and nickel. Electrodes are generally copper coated to prevent rusting and to increase their electrical conductivity. Electrodes are available in straight lengths and coils. Their diameters may be 1.6, 2.0, 2.4, 3, 4.0, 4.8, and 6.4 mm. The approximate value of currents to weld with 1.6, 3.2 and 6.4 mm diameter electrodes are 150–350, 250–800 and 650–1350 Amps respectively.\nWelding Operation.\nThe flux starts depositing on the joint to be welded. Since the flux is not electrically conductive when cold, the arc may be struck either by touching the electrode with the work piece or by placing steel wool between electrode and job before switching on the welding current or by using a high frequency unit. In all cases the arc is struck under a cover of flux. Flux otherwise is an insulator but once it melts due to heat of the arc, it becomes highly conductive and hence the current flow is maintained between the electrode and the workpiece through the molten flux. The upper portion of the flux, in contact with atmosphere, which is visible remains granular (unchanged) and can be reused. The lower, melted flux becomes slag, which is waste material and must be removed after welding.\nThe electrode is continuously fed to the joint to be welded at a predetermined speed. In semi-automatic welding sets the welding head is moved manually along the joint. In automatic welding a separate drive moves either the welding head over the stationary job or the job moves/rotates under the stationary welding head.\nThe arc length is kept constant by using the principle of a self-adjusting arc. If the arc length decreases, arc voltage will increase, arc current and therefore burn-off rate will increase thereby causing the arc to lengthen. The reverse occurs if the arc length increases more than the normal.\nA backing plate of steel or copper may be used to control penetration and to support large amounts of molten metal associated with the process.", "Engineering,_Manufacturing": 1.000007987, "qwen": "Yes"}
{"id": "5139836", "revid": "43001816", "url": "https://en.wikipedia.org/wiki?curid=5139836", "title": "Inventory investment", "text": "Inventory investment is a component of gross domestic product (GDP). What is produced in a certain country is naturally also sold eventually, but some of the goods produced in a given year may be sold in a later year rather than in the year they were produced. Conversely, some of the goods sold in a given year might have been produced in an earlier year. The difference between goods produced (production) and goods sold (sales) in a given year is called inventory investment. The concept can be applied to the economy as a whole or to an individual firm, however this concept is generally applied in macroeconomics (economy as a whole). Unintended unsold stock of goods increases inventory investment.\nDefinition of inventory investment.\nThus, if production per unit time exceeds sales per unit time, then inventory investment per unit time is positive; as a result, at the end of that period of time the stock of inventory inventories on hand will be greater than it was at the beginning. The reverse is true if production is less than sales.\nMathematical relationship of inventory investment to inventories.\nIn discrete time, the end-of-period stock of inventories minus the beginning-of-period stock of inventories equals the flow of inventory investment per time period.\nIn continuous time, the time derivative of the stock of inventories equals the instantaneous flow of inventory investment.\nIntended and unintended inventory investment.\nA positive flow of intended inventory investment occurs when a firm expects that sales will be high enough that the current level of inventories on hand may be insufficient—perhaps because in the presence of very short-term fluctuations in the timing of customer purchases, there is a risk of temporarily being unable to supply the product when a customer demands it. To avoid that prospect, the firm deliberately builds up its inventories—that is, engages in positive intended inventory investment by deliberately producing more than it expects to sell. Economists view this positive intended inventory investment as a form of spending—in effect, the firm is buying inventories from itself.\nConversely, if a firm decides that its current level of inventories is unjustifiably high—some of the inventories are taking up costly warehouse space while exceeding what is needed to prevent stock-outs—then it will engage in a negative flow of intended inventory investment. It does this by deliberately producing less than what it expects to sell.\nPositive or negative unintended inventory investment occurs when customers buy a different amount of the firm's product than the firm expected during a particular time period. If customers buy less than expected, inventories unexpectedly build up and unintended inventory investment turns out to have been positive. If customers buy more than expected, inventories unexpectedly decline and unintended inventory investment turns out to have been negative.\nEither positive or negative intended inventory investment can coincide with either positive or negative unintended inventory investment. They are separate, unrelated events: one is based on deliberate actions to adjust the stock of inventories, while the other results from mispredictions of customer demand.\nTo help reduce costs associated with inventory management, (holding costs, shortage costs, spoilage costs, etc.) inventory management practices like vendor managed inventory have been adopted by retailers.\nRelationship to macroeconomic equilibrium.\nIn macroeconomics, equilibrium in the goods market occurs when the supply of goods (output) equals the demand for goods (the sum of various types of expenditure—consumer expenditure, government expenditure on goods, net expenditures by people outside the country on the country's exports, fixed investment expenditure on physical capital, and intended inventory investment). If these are indeed equal for a particular time period, there is no unintended inventory investment and there is goods market equilibrium. If they are not equal, there is disequilibrium in the goods market. This is reflected in the presence of positive or negative unintended inventory investment.\nInventory investment over the business cycle.\nA typical business cycle plays out in the following way. Starting from some point in the business cycle, some group (consumers, government, purchasers of exports, etc.) decides for some reason to have a sustained increase in their spending. This may come as a surprise to producers, who initially experience negative inventory investment as their sales have unexpectedly exceeded their production. Now their inventories are too low, for two reasons: (1) Inventories have accidentally gone down, and (2) the optimal level of inventories—what producers want to have on hand—has gone up because sustained customer demand has gone up and there is increased danger of temporary stock-outs. In order to build inventories up to an appropriate level, firms engage in positive intended inventory investment. This positive flow of intended inventory investment continues until the target level of inventories is reached. During this time, the economy is in a boom both due to the original sustained increase in spending and due to the positive flow of intended inventory investment.\nAt some point, there is a sustained decline in some type of spending for some reason. (One reason may simply be that, once inventories reach their desired level, there stops being positive intended inventory investment; but there may be other reasons as well.) Then there is positive unintended inventory investment as firms are caught by surprise by the external drop in demand and they fail to simultaneously lower their production. Now inventories are too high, for two reasons: (1) They have accidentally risen, and (2) the optimal level of inventories is lower now due to the new, lower level of sustained demand. So in order to lower their inventories, firms deliberately cut back their production to below the level of demand by their customers, thus causing inventories to be deliberately drawn down—that is, intended inventory investment is negative. Intended inventory investment remains negative until the target level of inventories is reached. During this time, the economy, having peaked out, is in a downturn (a recession) both due to the sustained decrease in non-inventory expenditure and due to the negative flow of intended inventory investment.\nAt some point, there is a sustained increase in some type of spending for some reason. (One reason may simply be that, once inventories sink to their desired level, there stops being negative intended inventory investment, which goes up from negative to zero; but again there may be other reasons as well.) At this point there is negative unintended inventory investment as firms are caught by surprise by the external increase in demand and they fail to simultaneously raise their production. Now inventories are too low, again for two reasons, and we are back where we started in the cycle. The recession has bottomed out, sustained spending is once again high, target inventory levels are higher than actual inventory levels, and intended inventory investment is positive.", "Engineering,_Manufacturing": 0.9992222786, "qwen": "Yes"}
{"id": "5141141", "revid": "11877048", "url": "https://en.wikipedia.org/wiki?curid=5141141", "title": "2004 UEFA Intertoto Cup", "text": "The 2004 UEFA Intertoto Cup football finals (the summer football competition for European clubs that had not qualified for one of the two major UEFA competitions) were won by Lille, Schalke 04, and Villarreal. \nAll three teams advanced to the UEFA Cup.\nFirst round.\nFirst leg.\n\"The game was awarded 3–0 to Khazar Universiteti due to Schwarz-Weiß Bregenz fielding an ineligible player.\"\nSecond leg.\n\"2–2 on aggregate, Sloboda Tuzla won on away goals rule.\"\n\"The game was awarded 3–0 to Vllaznia due to Hapoel fielding an ineligible player. Vllaznia won 4–2 on aggregate.\"\n\"Vardar won 10–2 on aggregate.\"\n\"Slaven Belupo won 4–2 on aggregate.\"\n\"Sartid won 11–0 on aggregate.\"\n\"Marek Dupnitsa won 2–0 on aggregate.\"\n\"Spartak Moscow won 2–1 on aggregate.\"\n\"Teplice won 3–2 on aggregate.\"\n\"Thun won 2–0 on aggregate.\"\n\"Tescoma Zlín won 4–3 on aggregate.\"\n\"Khazar Universiteti won 5–1 on aggregate.\"\n\"4–4 on aggregate, Spartak Trnava won on away goals rule.\"\n\"Dinamo Minsk won 2–1 on aggregate.\"\n\"ZTS Dubnica won 4–0 on aggregate.\"\n\"Gent won 3–1 on aggregate.\"\n\"Cork City won 4–1 on aggregate.\"\n\"Vėtra won 4–0 on aggregate.\"\n\"Odense won 7–0 on aggregate.\"\n\"1–1 on aggregate, Tampere United won on away goals rule.\"\n\"Dinaburg won 4–0 on aggregate.\"\n\"Esbjerg won 7–1 on aggregate.\"\nSecond round.\nSecond leg.\n\"Tescoma Zlín won 3–0 on aggregate.\"\n\"Vėtra won 2–1 on aggregate.\"\n\"The game was awarded 3–0 to Genk due to Marek Dupnitsa fielding an ineligible player. Genk won 5–1 on aggregate.\"\n\"Villarreal won 5–0 on aggregate.\"\n\"Shinnik Yaroslavl won 4–1 on aggregate.\"\n\"Slovan Liberec won 7–1 on aggregate.\"\n\"Thun won 7–3 on aggregate.\"\n\"OFK Beograd won 5–1 on aggregate.\"\n\"Cork City won 1–0 on aggregate.\"\n\"Esbjerg won 2–1 on aggregate.\"\n\"Spartak Moscow won 5–1 on aggregate.\"\n\"Tampere United won 3–1 on aggregate.\"\n\"Dinamo Minsk won 4–3 on aggregate.\"\n\"Spartak Trnava won 3–1 on aggregate.\"\n\"1–1 on aggregate. Vardar won 4–3 on penalties.\"\n\"Slaven Belupo won 2–1 on aggregate.\"\nThird round.\nSecond leg.\n\"4–4 on aggregate, Atlético Madrid won on away goals rule.\"\n\"Nantes won 4–2 on aggregate.\"\n\"2–2 on aggregate, Genk won on away goals rule.\"\n\"Hamburger SV won 5–3 on aggregate.\"\n\"União de Leiria won 6–2 on aggregate.\"\n\"Schalke 04 won 7–1 on aggregate.\"\n\"Slovan Liberec won 2–1 on aggregate.\"\n\"Lille won 4–3 on aggregate.\"\n\"2–2 on aggregate, Slaven Belupo won on away goals rule.\"\n\"OFK Beograd won 1–0 on aggregate.\"\n\"Villarreal won 3–2 on aggregate.\"\n\"Esbjerg won 5–1 on aggregate.\"\nSemi-finals.\nSecond leg.\n\"Schalke 04 won 6–1 on aggregate.\"\n\"Lille won 4–1 on aggregate.\"\n\"União de Leiria won 2–0 on aggregate.\"\n\"2–2 on aggregate, Slovan Liberec won on away goals rule.\"\n\"Villarreal won 2–0 on aggregate.\"\n\"Atlético Madrid won 5–1 on aggregate.\"\nFinals.\nSecond leg.\n\"Schalke 04 won 3–1 on aggregate.\"\n\"2–2 on aggregate. Villareal won 3–1 on penalties.\"\n\"Lille won 2–0 on aggregate.\"", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "35227726", "revid": "5183450", "url": "https://en.wikipedia.org/wiki?curid=35227726", "title": "Management accounting in supply chains", "text": "Management accounting in supply chains (or supply chain controlling, SCC) is part of the supply chain management concept. This necessitates planning, monitoring, management and information about logistics and manufacturing processes throughout the value chain. The goal of management accounting in supply chains is optimizing these processes. This strategy focuses on supporting management.\nOverview.\nAs value chains become more complex due to globalization, supply chain management (SCM) has become increasingly relevant in theory and practice. SCM encompasses extensive management-control tasks. This range of subjects is summarized by the definition of supply-chain controlling. The transfer of existing management control systems (MCM) to the SCM is insufficient because these primarily aim at internal (company) needs. Beyond past-oriented, financial figures there must also be future-oriented measurement; a number of approaches exist in the literature.\nDefinition.\nSupply-chain management (SCM) has become increasingly relevant in theory and practice in light of more-complex supply chains. The SCM performs extensive operational tasks, including supply-chain controlling. Seuring transfers the three main concepts of German supply chain-controlling literature into the specific demands of SCM:\nThe rationality-oriented approach of supply-chain controlling coordinates all participants in the supply chain to improve performance. Common management systems and instruments for performance measurement are developed, enabling guidance for individual companies and the entire supply chain. The coordination-oriented approach supports the supply-chain leadership. Organizational objectives include the selection of strategic partners, the distribution of tasks among companies, process management and ensuring the provision of information to all participants. The information-oriented supply-chain controlling concept emphasizes providing partners with relevant information for decision-making. An efficient reporting structure must be implemented, including strategic and operative organizations in the system and their technical aspects.\nRequirements.\nA requirement for the supply chain is the support of cooperating companies, ensuring future cooperation; companies must focus on common tools and targets. For this, an understanding of processes within the participating companies is indispensable. Information exchange (including sensitive data) within a supply chain is necessary to ensure its control, with coordination among in-house information systems. The requirements for management accounting in supply chains are significantly higher than the provision of key figures, but this is a fundamental task.\nTasks and functions.\nThe tasks and functions of controlling may be transferred to management accounting in supply chains, supplemented by a cross-company approach. However, the past-oriented aspects of the traditional concept are inappropriate. Due to the strategic importance of supply-chain management, forward-looking control requirements must be taken into account. Because of the complexity of a supply chain, a focus on interface management is necessary. In the literature, several tasks and functions are defined. Management accounting in supply chains has the following features:\nAims.\nBecause of different controlling directions, in management accounting of supply chains different aims are pursued and influence each other. Again, the challenge is the cross-company factor. Independent companies must agree on a common strategy for the SCM and define common aims. Two types of aims exist: direct and indirect.\nDirect.\nDirect aims relate to the support of SCM and controlling. This ensures logistical processes between parties in a supply chain or the introduction of a common performance-measurement system for verification of lead times.\nIndirect.\nCompany-wide, generalized aims may be pursued with management accounting in supply chains. Examples are competitiveness, expanding cooperation, growth, market development and greater customer orientation.\nInstruments.\nManagement accounting in supply chains draws on modified traditional instruments of managerial accounting to accomplish cross-company objectives. There are two measuring instruments: the supply-chain map and the supply-chain operations reference (SCOR).\nSupply-chain scorecard.\nThe basic model of the balanced scorecard (BSC) was introduced by Kaplan and Norton in 1992. The BSC aims to achieve a balance between non-financial and financial measures. To use the scorecard in a cross-company context, several modifications of content and structure are necessary. The BSC consists of four generic perspectives, which are geared to the individual company. According to this, a generally accepted framework does not exist. From a common strategy, the supply-chain scorecard (SCS) maps cross-company measures. Brewer and Speh note that focusing on the supply chain requires four perspectives: \nIndependent of perspective, each should include internal and cross-company measures.\nCross-company activity-based costing.\nActivity-based costing is a model to assign indirect costs into direct ones. To use this model in the context of supply chains, there must be consistent defined and delimited cost and performance data. Since many companies participate in more than one supply chain, standardization across the sector is beneficial. Compatibility of information technology is important for improved data transfer, so manual entry is limited and high availability guaranteed. Several changes result from cross-company activity-based costing:\nSupply-chain performance-measurement system.\nA primary task of management accounting in supply chains is performance measurement. The key elements of strategic goals include the measurement of resources, output and flexibility. Efficient resource management is critical to profitability; without an acceptable output, customers will turn to other supply chains. In a changing environment, supply chains must adapt.\nMeasures for resource performance include total costs, distribution costs, manufacturing costs, measures of inventory and rate of return. Examples of performance measures are numbers of items produced, time required to produce, customer satisfaction and product quality (which is difficult to express numerically). Reductions in back orders, increased customer satisfaction and the ability to accommodate demand variations are advantages associated with flexibility.", "Engineering,_Manufacturing": 0.9997358918, "qwen": "Yes"}
{"id": "28877856", "revid": "869314", "url": "https://en.wikipedia.org/wiki?curid=28877856", "title": "2006 FIFA World Cup qualification – CONCACAF second round", "text": "This page provides the summaries of the CONCACAF second round matches for the 2006 FIFA World Cup qualification. The 14 top-ranked teams from the FIFA ranking for CONCACAF in May 2007 competed, along with the 10 winning teams from the first round.\nThere were 94 goals scored in 24 matches, for an average of 3.92 goals per match.\nFormat.\nIn this round 12 of the remaining 24 teams would be eliminated. There were 12 ties and the winners advanced to the next round. All games were scheduled to be played in home and away format.\nMatches.\nUnited States won 6–2 on aggregate and advanced to the third round.\nEl Salvador won 4–3 on aggregate and advanced to the third round.\nJamaica won 4–1 on aggregate and advanced to the third round.\nPanama won 7–0 on aggregate and advanced to the third round.\nCosta Rica won on the away goals rule after drawing 3–3 on aggregate and advanced to the third round.\nGuatemala won 4–2 on aggregate and advanced to the third round.\nHonduras won 6–1 on aggregate and advanced to the third round.\nCanada won 8–0 on aggregate and advanced to the third round.\nMexico won 18–0 on aggregate and advanced to the third round.\nSaint Kitts and Nevis won 5–2 on aggregate and advanced to the third round.\nTrinidad & Tobago won 6–0 on aggregate and advanced to the third round.\nSaint Vincent and the Grenadines won 6–3 on aggregate and advanced to the third round.", "Engineering,_Manufacturing": 1.0000100136, "qwen": "Yes"}
{"id": "28882268", "revid": "7903804", "url": "https://en.wikipedia.org/wiki?curid=28882268", "title": "Phönix C.I", "text": "The Phönix C.I, given serial numbers in the Phönix 121 range, was an Austro-Hungarian First World War reconnaissance and general-purpose Biplane built by Phönix and Lloyd.\nDevelopment.\nThe Phönix C.I was the first original design developed by the Phönix Flugzeug-Werke It was based on the Hansa-Brandenburg C.II that Phönix was building under licence. A conventional biplane with a rear fuselage/tailplane similar to aircraft designed by Ernst Heinkel. The C.I had a fixed tail-skid landing gear and was powered by a Hiero 6-cylinder inline piston engine, it had two tandem open cockpits for the pilot and observer/gunner. The company built 110 C.Is and then entered service with the KuKLFT in early 1918. After the First World War 30 aircraft were built by the Swedish Army engineering department fitted with Benz Bz.IV inline engines.\nDesignations and serials.\nPhönix C.I aircraft built by Phönix were serialled from Phönix C.I 121.01 to Phönix C.I 121.160 and Phönix C.I aircraft ordered from Lloyd (\"Ungarische Lloyd Flugzeug und Motorenfabrik AG\") were allocated serials from Phönix C.I(Ll) 49.01 to Phönix C.I(Ll) 49.100. Some 80 aircraft ordered from UFAG were not assigned serial nos, probably due to production being interrupted by the Armistice and 225 more were ordered but not built.", "Engineering,_Manufacturing": 0.997449398, "qwen": "Yes"}
{"id": "7575916", "revid": "35936988", "url": "https://en.wikipedia.org/wiki?curid=7575916", "title": "Build to order", "text": "Build to Order (BTO: sometimes referred to as Make to Order or Made to Order (MTO)) is a production approach where products are not built until a confirmed order for products is received. Thus, the end consumer determines the time and number of produced products. The ordered product is customized, meeting the design requirements of an individual, organization or business. Such production orders can be generated manually, or through inventory/production management programs. BTO is the oldest style of order fulfillment and is the most appropriate approach used for \"highly customized\" or \"low volume\" products. Industries with expensive inventory use this production approach. Moreover, \"Made to order\" products are common in the food service industry, such as at restaurants.\nBTO can be considered a Just in Time (JIT) production system, as components or products are only delivered just in time when demanded, in order to reduce wasted time and increase efficiency.\nImplementation.\nThis approach is considered good for highly configured products, e.g. automobiles, bicycles, computer servers, or for products where holding inventories is very expensive, e.g. aircraft. In general, the BTO approach has become more popular in the last few years ever since high-tech companies such as Dell, BMW, Compaq and Gateway successfully implemented the system into their business operations.\nBTO in the automotive industry.\nIn an automotive context, BTO is a demand driven production approach where a product is scheduled and built in response to a confirmed order received for it from a final customer. The final customer refers to a known individual owner and excludes all orders by the original equipment manufacturer (OEM), national sales companies (NSC), dealers or point of sales, bulk orders or other intermediaries in the supply chain. BTO excludes the order amendment function, whereby forecast orders in the pipeline are amended to customer requirements, as this is seen as another level of sophistication for a build to stock (BTS) system (also known as build to forecast (BTF)).\nBTS is the dominant approach used today across many industries and refers to products that are built before a final purchaser has been identified, with production volume driven by historical demand information. This high stock level, endemic across the auto industry allows some dealers to find an exact or very close match to the customer's desired vehicle within the dealer networks and supplier parks. The vehicle can then be delivered as soon as transport can be arranged. This has been used to justify stock levels. Whilst providing a rapid response to customer demand, the approach is expensive, mainly in terms of stock, but also transportation as finished goods are rarely where they are required. Holding stock of such a high cash value as finished goods is a key driver of the current crisis in the automotive industry - a crisis that could be eased by implementation of a BTO system.\nA BTO system does not mean that all suppliers in the supplier chain should be producing only when a customer order has been confirmed. Clearly, it would not make economic sense for a manufacturer of low value high volume parts to employ BTO. It is appropriate that these should be identified and built to a supplier order, effectively BTS. Part of the challenge in a BTO supplier network is in the identification of which suppliers should be BTO and which BTS. The point in the supply chain when this change occurs is called the ‘decoupling point’. Currently, the majority of automotive supply chains lack a decoupling point and the dominant BTS approach has resulted in billions of dollars of capital being tied up in stock in the supply chain.\nSome firms build all their products to order while others practice (BTS). Given the widespread proliferation of products, there are a number of manufacturers taking a combined approach, where some items are BTS and others are BTO, which is commonly referred to as \"hybrid BTO\".\nAdvantages.\nThe main advantages of the BTO approach in environments of high product variety is the ability to supply the customer with the exact product specification required, the reduction in sales discounts and finished good inventory, as well a reduction in stock obsolescence risk. \nAdditionally, flexibility and customer lead time are improved to a match changes in consumer demand. Moreover, a business’ cash flow can be increased with BTO.\nDisadvantages.\nThe main disadvantage of BTO is manufacturers are susceptible to market demand fluctuations leading to a reduced capacity utilization in manufacturing. Hence, to ensure an effective use of production resources, a BTO approach should be coupled with proactive demand management. Finding the correct and appropriate balance of BTO and BTS to maintain stock levels appropriate to both the market requirement and operational stability is a current area of academic research. In Retail, an occurring problem may be customers choosing an alternative product that is available at that time and place, as they are not willing to wait for the BTO product to arrive.\nMoreover, compared to mass production, customization of products implies higher costs. Thus, price-conscious customers may be turned away, as they do not feel a strong need for customized products and would therefore choose a more standardized product instead.\nRelated approaches.\nRelated approaches to BTO include the following:\nEngineer to Order (ETO) approach.\nIn ETO, after an order is received, a part of or the whole design starts to be developed. Construction by general contractors and plant construction by engineering companies are categorized as ETO.\nAssemble to Order (ATO) approach.\nThis strategy requires that basic parts of the product are already manufactured, however not yet assembled. Once a customer's order has been received, the parts of the product are quickly being assembled and sent out.\nTogether with the BTS approach, these strategies form the spectrum of order fulfillment strategies a firm can adopt.", "Engineering,_Manufacturing": 0.9996564388, "qwen": "Yes"}
{"id": "7577325", "revid": "125972", "url": "https://en.wikipedia.org/wiki?curid=7577325", "title": "Order fulfillment", "text": "Order fulfillment (in British English: order fulfilment) is in the most general sense the complete process from point of sales inquiry to delivery of a product to the customer. Sometimes, it describes the more narrow act of distribution or the logistics function. In the broader sense, it refers to the way firms respond to customer orders.\nClassification.\nThe first research towards defining order fulfillment strategies was published by Hans Wortmann, and was continued by Hal Mather in his discussion of the P:D ratio, whereby P is defined as the production lead time, i.e. how long it takes to manufacture a product, and D is the demand lead time. D can be viewed as:\nBased on comparing P and D, a firm has several basic strategic order fulfillment options:\nProcesses.\nIn the broader sense, the possible processes in a logistic-production system are:\nStrategic importance.\nThe order fulfillment strategy also determines the de-coupling point in the supply chain, which describes the point in the system where the \"push\" (or forecast-driven) and \"pull\" (or demand-driven see Demand chain management) elements of the supply chain meet. The decoupling point always is an inventory buffer that is needed to cater for the discrepancy between the sales forecast and the actual demand (i.e. the forecast error). Typically, the higher the P:D ratio, the more the firm relies on forecasts and inventories. Hal Mather suggests three ways to tackle this \"planning dilemma\":\nIt has become increasingly necessary to move the de-coupling point in the supply chain to minimize the dependence on the forecast and to maximize the reactionary or demand-driven supply chain elements. This initiative in the distribution elements of the supply chain corresponds to the Just-in-time initiatives pioneered by Toyota.\nThe order fulfillment strategy has also strong implications on how firms customize their products and deal with product variety. Strategies that can be used to mitigate the impact of product variety include modularity, option bundling, late configuration, and build to order (BTO) strategies—all of which are generally referred as mass customization strategies. The decoupling point can place a much stronger emphasis on the supply chain based on the process as well as the nature of supply chain configurations.", "Engineering,_Manufacturing": 0.9991624355, "qwen": "Yes"}